Surgical cutting and fastening instrument with apparatus for determining cartridge and firing motion status

[0001] In general, the present invention relates to surgical instruments and, more particularly, to surgical cutting and fastening instruments with an electronic sensor capable of determining cartridge and firing motion status.

[0002] Surgical instruments often comprise a distal end effector that engages tissue at a surgical site to achieve a diagnostic or therapeutic effect (e.g., endocutter, grasper, cutter, staplers, clip applier, access device, drug/gene therapy delivery device, and energy device using ultrasound, RF, laser, etc.). For example, known surgical staplers include an end effector that simultaneously makes a longitudinal incision in tissue and applies lines of staples on opposing sides of the incision. Such surgical staplers often have a firing bar that translates in the end effector in response to manual or motorized drive motions. The firing bar drives a cutting element through tissue held in the end effector and drives a plurality of wedges against drivers that support the staples to effect the firing of the staples from the end effector.

[0003] Surgical instruments generally do not provide sufficient user feedback during operation. In general, for example, many robotically-controlled surgical staplers do not alert the user to the deployment forces and position of the cutting element during the cutting and stapling operations. Consequently, motor-driven endocutters where the drive motions are actuated by merely pressing a button are generally not accepted by physicians. Accordingly, there is a need in the art for surgical instruments that address some of these shortcomings.

[0004] The foregoing discussion is intended only to illustrate some of the shortcomings present in the field of the invention at the time and should not be taken as a disavowal of claim scope.

[0005] The present disclosure relates to an electronic sensor for determining the position of a firing element in the end effector and/or the status of a staple cartridge in the end effector. The electronic sensor has a resistive member supported in the end effector. A firing element configured to translate within the end effector movingly contacts the resistive member as the firing member translates. As the firing element translates, a cutting element attached thereto can sever resistors in the resistive member. The electronic sensor can communicate with a memory device, processor and indicator.

[0006] According to general aspects of various embodiments of the present invention, there is provided a surgical instrument comprising a surgical end effector comprising an elongate channel having a proximal end and a distal end; a firing element configured to selectively translate between said proximal end of said elongate channel and said distal end of said elongate channel upon application of a driving motion thereto; a resistive member supported for moving contact by said firing element as said firing element is driven from said proximal end to said distal end of said elongate channel such that said resistive member generates output signals indicative of positions of said firing element within said elongate channel; and a memory device operably communicating with said resistive member and configured to record said output signals as said firing element translates through said elongate channel.

[0007] In accordance with other general aspects of various embodiments of the present invention, there is provided a staple cartridge for use in connection with a surgical instrument, said staple cartridge comprising a cartridge body configured to be operably supported by the surgical instrument such that a firing element of the surgical instrument may longitudinally translate through said cartridge body upon application of a driving motion thereto; and a resistive member supported on said cartridge body for moving contact by the firing element as the firing element is translated therethrough, said resistive member configured to operably communicate output signals indicative of positions of the firing element within said cartridge body to a memory portion of the surgical instrument.

[0008] In accordance with still other general aspects, various embodiments of the present invention are directed to a surgical instrument, comprising a robotic system comprising a processor and a surgical end effector operably interfacing with said robotic system to receive drive motions therefrom. The surgical end effector comprises an elongate channel having a proximal end and a distal end; a firing element configured to selectively translate between said proximal end of said elongate channel and said distal end of said elongate channel upon application of a driving motion thereto from said robotic system; and a resistive member supported for moving contact by said firing element as said firing element is driven from said proximal end to said distal end of said elongate channel such that said resistive member generates output signals indicative of positions of said firing element within said elongate channel and communicates said output signals to said processor.

[0044] This detailed description discloses, among other things, electronic sensor arrangements for use in the end effector of a surgical instrument. In various embodiments, the electronic sensor determines the position of a firing element in the end effector and/or the status of a staple cartridge in the end effector. The unique and novel aspects of the present disclosure may enable a variety of different electronic sensors to be effectively employed in connection with a variety of types and forms of surgical instruments, end effectors and staple cartridges. Although the description herein refers to cutting/stapling operations and the like, it should be recognized that this is an exemplary embodiment and is not meant to be limiting. Other tissue-fastening techniques may also be used. Furthermore, in other embodiments, different types of end effectors may be used, such as end effectors for other types of surgical devices, such as graspers, cutters, staplers, clip appliers, access devices, drug/gene therapy devices, ultrasound, RF or laser devices, etc.

[0045] Applicant of the present application also owns the following patent applications, which are each herein incorporated by reference in their respective entireties:

• • [0046] U.S. patent application Ser. No. 13/118,272, now U.S. Patent Application Publication No. 2011/0290856; entitled ROBOTICALLY-CONTROLLED SURGICAL INSTRUMENT WITH FORCE-FEED CAPABILITIES;
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  • [0048] U.S. patent application Ser. No. 11/343,803, now U.S. Pat. No. 7,845,537, entitled SURGICAL INSTRUMENT HAVING RECORDING CAPABILITIES;
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  • [0050] U.S. patent application Ser. No. 11/343,573, now U.S. Pat. No. 7,416,101, entitled MOTOR-DRIVEN SURGICAL CUTTING AND FASTENING INSTRUMENT WITH LOADING FORCE FEEDBACK;
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  • [0052] U.S. patent application Ser. No. 11/343,447, now U.S. Pat. No. 7,770,775, entitled MOTOR-DRIVEN SURGICAL CUTTING AND FASTENING INSTRUMENT WITH ADAPTIVE USER FEEDBACK;
  • [0053] U.S. patent application Ser. No. 11/343,562, now U.S. Pat. No. 7,568,603, entitled MOTOR-DRIVEN SURGICAL CUTTING AND FASTENING INSTRUMENT WITH ARTICULATABLE END EFFECTOR;
  • [0054] U.S. patent application Ser. No. 11/344,024, now U.S. Pat. No. 8,186,555, entitled MOTOR-DRIVEN SURGICAL CUTTING AND FASTENING INSTRUMENT WITH MECHANICAL CLOSURE SYSTEM;
  • [0055] U.S. patent application Ser. No. 11/343,321, now U.S. Patent Publication No. 2007/0175955, entitled SURGICAL CUTTING AND FASTENING INSTRUMENT WITH CLOSURE TRIGGER LOCKING MECHANISM;
  • [0056] U.S. patent application Ser. No. 11/343,563, now U.S. Patent Publication No. 2007/0175951, entitled GEARING SELECTOR FOR A POWERED SURGICAL CUTTING AND FASTENING STAPLING INSTRUMENT;
  • [0057] U.S. patent application Ser. No. 11/344,020, now U.S. Pat. No. 7,464,846, entitled SURGICAL INSTRUMENT HAVING A REMOVABLE BATTERY;
  • [0058] U.S. patent application Ser. No. 11/343,439, now U.S. Pat. No. 7,644,848, entitled ELECTRONIC LOCKOUTS AND SURGICAL INSTRUMENT INCLUDING SAME;
  • [0059] U.S. patent application Ser. No. 11/343,547, now U.S. Pat. No. 7,753,904, entitled ENDOSCOPIC SURGICAL INSTRUMENT WITH A HANDLE THAT CAN ARTICULATE WITH RESPECT TO THE SHAFT;
  • [0060] U.S. patent application Ser. No. 11/344,021, now U.S. Pat. No. 7,464,849, entitled ELECTRO-MECHANICAL SURGICAL INSTRUMENT WITH CLOSURE SYSTEM AND ANVIL ALIGNMENT COMPONENTS;
  • [0061] U.S. patent application Ser. No. 11/343,546, now U.S. Patent Publication No. 2007/0175950, entitled DISPOSABLE STAPLE CARTRIDGE HAVING AN ANVIL WITH TISSUE LOCATOR FOR USE WITH A SURGICAL CUTTING AND FASTENING INSTRUMENT AND MODULAR END EFFECTOR SYSTEM THEREFOR;
  • [0062] U.S. patent application Ser. No. 11/343,545, now U.S. Pat. No. 8,708,213, entitled SURGICAL INSTRUMENT HAVING A FEEDBACK SYSTEM;
  • [0063] U.S. patent application Ser. No. 13/021,105, now U.S. Pat. No. 8,172,124, entitled SURGICAL INSTRUMENT HAVING RECORDING CAPABILITIES;
  • [0064] U.S. patent application Ser. No. 13/118,259, now U.S. Pat. No. 8,684,253, entitled SURGICAL INSTRUMENT WITH WIRELESS COMMUNICATION BETWEEN A CONTROL UNIT OF A ROBOTIC SYSTEM AND REMOTE SENSOR;
  • [0065] U.S. patent application Ser. No. 13/118,210, now U.S. Pat. No. 8,752,749, entitled ROBOTICALLY-CONTROLLED DISPOSABLE MOTOR DRIVEN LOADING UNIT;
  • [0066] U.S. patent application Ser. No. 13/118,194, now U.S. Pat. No. 8,992,422, entitled ROBOTICALLY-CONTROLLED ENDOSCOPIC ACCESSORY CHANNEL;
  • [0067] U.S. patent application Ser. No. 13/118,253, now U.S. Patent Publication No. 2011/0295269, entitled ROBOTICALLY-CONTROLLED MOTORIZED SURGICAL INSTRUMENT;
  • [0068] U.S. patent application Ser. No. 13/118,278, now U.S. Patent Publication No. 2011/0290851, entitled ROBOTICALLY-CONTROLLED SURGICAL STAPLING DEVICES THAT PRODUCE FORMED STAPLES HAVING DIFFERENT LENGTHS;
  • [0069] U.S. patent application Ser. No. 13/118,190, now U.S. Patent Publication No. 2011/0288573, entitled ROBOTICALLY-CONTROLLED MOTORIZED SURGICAL CUTTING AND FASTENING INSTRUMENT;
  • [0070] U.S. patent application Ser. No. 13/118,223, now U.S. Pat. No. 8,931,682, entitled ROBOTICALLY-CONTROLLED SHAFT BASED ROTARY DRIVE SYSTEMS FOR SURGICAL INSTRUMENTS;
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  • [0072] U.S. patent application Ser. No. 13/118,246, now U.S. Patent Publication No. 2011/0290853, entitled ROBOTICALLY-DRIVEN SURGICAL INSTRUMENT WITH E-BEAM DRIVER;
  • [0073] U.S. patent application Ser. No. 13/118,241, now U.S. Patent Publication No. 2012/0298719, entitled SURGICAL STAPLING INSTRUMENTS WITH ROTATABLE STAPLE DEPLOYMENT ARRANGEMENTS; and
  • [0074] U.S. patent application Ser. No. 13/372,195, now U.S. Patent Publication No. 2012/0292367 entitled ROBOTICALLY-CONTROLLED END EFFECTOR.

[0075] Certain exemplary embodiments will now be described to provide an overall understanding of the principles of the structure, function, manufacture, and use of the devices and methods disclosed herein. One or more examples of these embodiments are illustrated in the accompanying drawings. Those of ordinary skill in the art will understand that the devices and methods specifically described herein and illustrated in the accompanying drawings are non-limiting exemplary embodiments and that the scope of the various embodiments of the present invention is defined solely by the claims. Reference throughout the specification to “various embodiments,” “some embodiments,” “one embodiment,” or “an embodiment”, or the like, means that a particular feature, structure, or characteristic described in connection with the embodiment is included in at least one embodiment. Thus, appearances of the phrases “in various embodiments,” “in some embodiments,” “in one embodiment”, or “in an embodiment”, or the like, in places throughout the specification does not necessarily refer to the same embodiment. Furthermore, the particular features, structures, or characteristics illustrated or described in connection with one exemplary embodiment may be combined with the features, structures, or characteristics of other exemplary embodiments in any suitable manner in one or more embodiments. Such modifications and variations are intended to be included within the scope of the present disclosure.

[0076] This Detailed Description will first describe a motor-driven, power-assist surgical cutting and fastening instrument according to some embodiments of the present disclosure. However, those of ordinary skill in the art will appreciate that a surgical instrument according to various embodiments of the present disclosure may be powered and controlled in an alternative manner, for example, by manual force and/or robotic controls. As described in greater detail below, the end effector of the motor-driven, power-assist surgical instrument could alternatively be powered and controlled by a robotic system.

[0077] FIGS. 1 and 2 depict a motor-driven, power-assist surgical cutting and fastening instrument 10 according to various embodiments of the present invention. The illustrated embodiment is an endoscopic surgical instrument 10 and in general, the embodiments of the instrument 10 described herein are endoscopic surgical cutting and fastening instruments. It should be noted, however, that according to other embodiments of the present invention, the instrument 10 may be a non-endoscopic surgical cutting instrument, such as a laproscopic instrument. Additionally, the person of ordinary skill in the art will readily appreciate that the various methods and devices disclosed herein can be used in numerous surgical procedures and applications including, for example, in connection with open surgical procedures. As the present Detailed Description proceeds, those of ordinary skill in the art will further appreciate that the various instruments disclosed herein can be inserted into a body in any way, such as through a natural orifice, through an incision or puncture hole formed in tissue, etc. The working portions or end effector portions of the instruments can be inserted directly into a patient's body or can be inserted through an access device that has a working channel through which the end effector and elongated shaft of a surgical instrument can be advanced.

[0078] The surgical instrument 10 depicted in FIGS. 1 and 2 comprises a handle 6, a shaft 8, and an articulating end effector 12 pivotally connected to the shaft 8 at an articulation pivot 14. An articulation control 16 may be provided adjacent to the handle 6 to effect rotation of the end effector 12 about the articulation pivot 14. It will be appreciated that various embodiments may include a non-pivoting end effector, and therefore may not have an articulation pivot 14 or articulation control 16.

[0079] In the illustrated embodiment, the end effector 12 is configured to act as an endocutter for clamping, severing and stapling tissue, however, in other embodiments different techniques for fastening or sealing the severed tissue may be used. For example, end effectors that use RF energy or adhesives to fasten the severed tissue may also be used. U.S. Pat. No. 5,709,680, entitled “Electrosurgical Hemostatic Device” to Yates et al., and U.S. Pat. No. 5,688,270, entitled “Electrosurgical Hemostatic Device With Recessed And/Or Offset Electrodes” to Yates et al., which are incorporated herein by reference in their respective entireties, disclose cutting instruments that use RF energy to fasten the severed tissue. U.S. patent application Ser. No. 11/267,811 now U.S. Pat. No. 7,673,783 to Morgan et al. and U.S. patent application Ser. No. 11/267,383, now U.S. Pat. No. 7,607,557 to Shelton et al., which are also incorporated herein by reference in their respective entireties, disclose cutting instruments that use adhesives to fasten the severed tissue.

[0080] The handle 6 of the instrument 10 may include a closure trigger 18 and a firing trigger 20 for actuating the end effector 12. It will be appreciated that instruments having end effectors directed to different surgical tasks may have different numbers or types of triggers or other suitable controls for operating the end effector 12. The end effector 12 is shown separated from the handle 6 by a preferably elongate shaft 8. In one embodiment, a clinician or operator of the instrument 10 may articulate the end effector 12 relative to the shaft 8 by utilizing the articulation control 16, as described in more detail in pending U.S. Pat. No. 7,670,334, issued Mar. 2, 2010, entitled “Surgical Instrument Having An Articulating End Effector,” by Geoffrey C. Hueil et al., which is incorporated herein by reference in its entirety.

[0081] In this example, the end effector 12 includes, among other things, a staple channel 22 and a pivotally translatable clamping member, such as an anvil 24, which are maintained at a spacing that assures effective stapling and severing of tissue clamped in the end effector 12. The handle 6 includes a pistol grip 26 toward which a closure trigger 18 is pivotally drawn by the clinician to cause clamping or closing of the anvil 24 towards the staple channel 22 of the end effector 12 to thereby clamp tissue positioned between the anvil 24 and channel 22. The firing trigger 20 is farther outboard of the closure trigger 18. Once the closure trigger 18 is locked in the closure position as further described below, the firing trigger 20 may rotate slightly toward the pistol grip 26 so that it can be reached by the operator using one hand. Then the operator may pivotally draw the firing trigger 20 toward the pistol grip 26 to cause the stapling and severing of clamped tissue in the end effector 12. In other embodiments, different types of clamping members besides the anvil 24 could be used, such as, for example, an opposing jaw, etc.

[0082] The terms “proximal” and “distal” are used herein with reference to a clinician manipulating the handle portion of the surgical instrument. The term “proximal” referring to the portion closest to the clinician and the term “distal” referring to the portion located away from the clinician. It will be further appreciated that, for convenience and clarity, spatial terms such as “vertical”, “horizontal”, “up”, and “down” may be used herein with respect to the drawings. However, surgical instruments are used in many orientations and positions, and these terms are not intended to be limiting and/or absolute.

[0083] In the illustrated embodiment, the closure trigger 18 may be actuated first. Once the clinician is satisfied with the positioning of the end effector 12, the clinician may draw back the closure trigger 18 to its fully closed, locked position proximate to the pistol grip 26. The firing trigger 20 may then be actuated. The firing trigger 20 returns to the open position (shown in FIGS. 1 and 2) when the clinician removes pressure, as described more fully below. A release button on the handle 6, when depressed may release the locked closure trigger 18.

[0084] FIGS. 3-6 show embodiments of a rotary-driven end effector 12 and shaft 8 according to various embodiments. FIG. 3 is an exploded view of the end effector 12 according to various embodiments. As shown in the illustrated embodiment, the end effector 12 may include, in addition to the previously-mentioned channel 22 and anvil 24, a cutting instrument 32, a sled 33, a staple cartridge 34 that is removably seated in the channel 22, and a helical screw shaft 36. The cutting instrument 32 may be, for example, a knife. The anvil 24 may be pivotably opened and closed at pivot pins 25 connected to the proximate end of the channel 22. The anvil 24 may also include a tab 27 at its proximate end that is inserted into a component of the mechanical closure system (described further below) to open and close the anvil 24. When the closure trigger 18 is actuated, that is, drawn in by a user of the instrument 10, the anvil 24 may pivot about the pivot pins 25 into the clamped or closed position. If clamping of the end effector 12 is satisfactory, the operator may actuate the firing trigger 20, which, as explained in more detail below, causes the knife 32 and sled 33 to travel longitudinally along the channel 22, thereby cutting tissue clamped within the end effector 12. The movement of the sled 33 along the channel 22 causes the staples (not shown) of the staple cartridge 34 to be driven through the severed tissue and against the closed anvil 24, which turns the staples to fasten the severed tissue. In various embodiments, the sled 33 may be an integral component of the cartridge 34. U.S. Pat. No. 6,978,921, entitled “SURGICAL STAPLING INSTRUMENT INCORPORATING AN E-BEAM FIRING MECHANISM” to Shelton, IV et al., which is incorporated herein by reference in its entirety, provides more details about such two-stroke cutting and fastening instruments. The sled 33 may be part of the cartridge 34, such that when the knife 32 retracts following the cutting operation, the sled 33 does not retract.

[0085] FIGS. 4 and 5 are exploded views and FIG. 6 is a side view of the end effector 12 and shaft 8 according to various embodiments. As shown in the illustrated embodiment, the shaft 8 may include a proximate closure tube 40 and a distal closure tube 42 pivotably linked by a pivot link 44. The distal closure tube 42 includes an opening 45 into which the tab 27 on the anvil 24 is inserted in order to open and close the anvil 24, as further described below. Disposed inside the closure tubes 40, 42 may be a proximate spine tube 46. Disposed inside the proximate spine tube 46 may be a main rotational (or proximate) drive shaft 48 that communicates with a secondary (or distal) drive shaft 50 via a bevel gear assembly 52. The secondary drive shaft 50 is connected to a drive gear 54 that engages a proximate drive gear 56 of the helical screw shaft 36. The vertical bevel gear 52b may sit and pivot in an opening 57 in the distal end of the proximate spine tube 46. A distal spine tube 58 may be used to enclose the secondary drive shaft 50 and the drive gears 54, 56. Collectively, the main drive shaft 48, the secondary drive shaft 50, and the articulation assembly (e.g., the bevel gear assembly 52a-c) are sometimes referred to herein as the “main drive shaft assembly.”

[0086] A bearing 38, positioned at a distal end of the staple channel 22, receives the helical drive screw 36, allowing the helical drive screw 36 to freely rotate with respect to the channel 22. The helical screw shaft 36 may interface with a threaded opening (not shown) of the knife 32 such that rotation of the shaft 36 causes the knife 32 to translate distally or proximately (depending on the direction of the rotation) through the staple channel 22. Accordingly, when the main drive shaft 48 is caused to rotate by actuation of the firing trigger 20 (as explained in more detail below), the bevel gear assembly 52a-c causes the secondary drive shaft 50 to rotate, which in turn, because of the engagement of the drive gears 54, 56, causes the helical screw shaft 36 to rotate, which causes the knife driving member 32 to travel longitudinally along the channel 22 to cut any tissue clamped within the end effector 12.

[0087] In various embodiments, the staple channel 22 has a proximal end 23a and a distal end 23b and the knife or cutting element 32 is configured to travel longitudinally through the channel 22 between the proximal end 23a and the distal end 23b when a driving motion is applied to the cutting element 32. In other embodiments, the staple channel 22 has an interior surface 28 and a slot 30 that extends through the interior surface 28. See FIG. 12. The knife 32 can translate along the slot 30 as it travels longitudinally through the staple channel 22. The sled 33 may be made of, for example, plastic, and may have a sloped distal surface. As the sled 33 traverses the channel 22, the sloped forward surface may push up or drive the staples in the staple cartridge through the clamped tissue and against the anvil 24. The anvil 24 turns the staples, thereby stapling the severed tissue. When the knife 32 is retracted, the knife 32 and sled 33 may become disengaged, thereby leaving the sled 33 at the distal end of the channel 22 or the sled may return with the knife.

[0088] As described above, because of the lack of user feedback for the cutting/stapling operation, there is a general lack of acceptance among physicians of motor-driven endocutters where the cutting/stapling operation is actuated by merely pressing a button. In contrast, embodiments of the present invention provide a motor-driven endocutter with user-feedback of the deployment, force and/or position of the cutting instrument 32 in end effector 12.

[0089] FIGS. 7-10 illustrate an exemplary embodiment of a motor-driven endocutter, and in particular the handle thereof, that provides user-feedback regarding the deployment and loading force of the cutting instrument 32 in the end effector 12. In addition, the embodiment may use power provided by the user in retracting the firing trigger 20 to power the device (a so-called “power assist” mode). The embodiment may be used with the rotary driven end effector 12 and shaft 8 embodiments described above.

[0090] As shown in the illustrated embodiment, the handle 6 includes exterior lower side pieces 59, 60 and exterior upper side pieces 61, 62 that fit together to form, in general, the exterior of the handle 6. A battery 64, such as a Li ion battery, may be provided in the pistol grip portion 26 of the handle 6. The battery 64 powers a motor 65 disposed in an upper portion of the pistol grip portion 26 of the handle 6. According to various embodiments, the motor 65 may be a DC brushed driving motor having a maximum rotation of, approximately, 5000 RPM. The motor 65 may drive a 90° bevel gear assembly 66 comprising a first bevel gear 68 and a second bevel gear 70. The bevel gear assembly 66 may drive a planetary gear assembly 72. The planetary gear assembly 72 may include a pinion gear 74 connected to a drive shaft 76. The pinion gear 74 may drive a mating ring gear 78 that drives a helical gear drum 80 via a drive shaft 82. A ring 84 may be threaded on the helical gear drum 80. Thus, when the motor 65 rotates, the ring 84 is caused to travel along the helical gear drum 80 by means of the interposed bevel gear assembly 66, planetary gear assembly 72 and ring gear 78.

[0091] The handle 6 may also include a run motor sensor 110 (see FIG. 10) in communication with the firing trigger 20 to detect when the firing trigger 20 has been drawn in (or “closed”) toward the pistol grip portion 26 of the handle 6 by the operator to thereby actuate the cutting/stapling operation by the end effector 12. The sensor 110 may be a proportional sensor such as, for example, a rheostat or variable resistor. When the firing trigger 20 is drawn in, the sensor 110 detects the movement, and sends an electrical signal indicative of the voltage (or power) to be supplied to the motor 65. When the sensor 110 is a variable resistor or the like, the rotation of the motor 65 may be generally proportional to the amount of movement of the firing trigger 20. That is, if the operator only draws or closes the firing trigger 20 in a short distance, the rotation of the motor 65 is relatively low. When the firing trigger 20 is fully drawn in (or in the fully closed position), the rotation of the motor 65 is at its maximum. In other words, the harder the user pulls on the firing trigger 20, the more voltage is applied to the motor 65, causing greater rates of rotation.

[0092] The handle 6 may include a middle handle piece 104 adjacent to the upper portion of the firing trigger 20. The handle 6 also may comprise a bias spring 112 connected between posts on the middle handle piece 104 and the firing trigger 20. The bias spring 112 may bias the firing trigger 20 to its fully open position. In that way, when the operator releases the firing trigger 20, the bias spring 112 will pull the firing trigger 20 to its open position, thereby removing actuation of the sensor 110, thereby stopping rotation of the motor 65. Moreover, by virtue of the bias spring 112, any time a user closes the firing trigger 20, the user will experience resistance to the closing operation, thereby providing the user with feedback as to the amount of rotation exerted by the motor 65. Further, the operator could stop retracting the firing trigger 20 to thereby remove force from the sensor 110, to thereby stop the motor 65. As such, the user may stop the deployment of the end effector 12, thereby providing a measure of control of the cutting/fastening operation to the operator.

[0093] In various embodiments, the distal end of the helical gear drum 80 includes a distal drive shaft 120 that drives a ring gear 122, which mates with a pinion gear 124. The pinion gear 124 is connected to the main drive shaft 48 of the main drive shaft assembly. In that way, rotation of the motor 65 causes the main drive shaft assembly to rotate, which causes actuation of the end effector 12, as described above.

[0094] A ring 84 threaded on or otherwise attached to the helical gear drum 80 may include a post 86 that is disposed within a slot 88 of a slotted arm 90. See FIGS. 8 and 9. The slotted arm 90 has an opening 92 in its opposite end 94 that receives a pivot pin 96 that is connected between the handle exterior side pieces 59, 60. The pivot pin 96 is also disposed through an opening 100 in the firing trigger 20 and an opening 102 in the middle handle piece 104.

[0095] In addition, the handle 6 may include a reverse motor sensor (or end-of-stroke sensor) 130 and a stop motor (or beginning-of-stroke) sensor 142. See FIG. 10. In various embodiments, the reverse motor sensor 130 may be a limit switch located at the distal end of the helical gear drum 80 such that the ring 84 threaded on the helical gear drum 80 contacts and activates the reverse motor sensor 130 when the ring 84 reaches the distal end of the helical gear drum 80. The reverse motor sensor 130, when activated, sends a signal to the motor 65 to reverse its rotation direction, thereby withdrawing the knife 32 of the end effector 12 following the cutting operation.

[0096] The stop motor sensor 142 may be, for example, a normally-closed limit switch. In various embodiments, it may be located at the proximate end of the helical gear drum 80 so that the ring 84 activates the switch 142 when the ring 84 reaches the proximate end of the helical gear drum 80.

[0097] In operation, when an operator of the instrument 10 pulls back the firing trigger 20, the sensor 110 detects the deployment of the firing trigger 20 and sends a signal to the motor 65 to cause forward rotation of the motor 65, for example, at a rate proportional to how hard the operator pulls back the firing trigger 20. The forward rotation of the motor 65 in turn causes the ring gear 78 at the distal end of the planetary gear assembly 72 to rotate, thereby causing the helical gear drum 80 to rotate, causing the ring 84 threaded on the helical gear drum 80 to travel distally along the helical gear drum 80. The rotation of the helical gear drum 80 also drives the main drive shaft assembly as described above, which in turn causes deployment of the knife 32 in the end effector 12. That is, the knife 32 and sled 33 are caused to traverse the channel 22 longitudinally, thereby cutting tissue clamped in the end effector 12. Also, the stapling operation of the end effector 12 is caused to happen in embodiments where a stapling-type end effector 12 is used.

[0098] By the time the cutting/stapling operation of the end effector 12 is complete, the ring 84 on the helical gear drum 80 will have reached the distal end of the helical gear drum 80, thereby causing the reverse motor sensor 130 to be activated, which sends a signal to the motor 65 to cause the motor 65 to reverse its rotation. This in turn causes the knife 32 to retract, and also causes the ring 84 on the helical gear drum 80 to move back to the proximate end of the helical gear drum 80.

[0099] The middle handle piece 104 (FIG. 7) includes a backside shoulder 106 that engages the slotted arm 90, as best shown in FIG. 8. The middle handle piece 104 also has a forward motion stop 107 that engages the firing trigger 20. See FIG. 10. The movement of the slotted arm 90 is controlled, as explained above, by rotation of the motor 65. When the slotted arm 90 rotates counter clockwise as the ring 84 travels from the proximate end of the helical gear drum 80 to the distal end, the middle handle piece 104 will be free to rotate counter clockwise. Thus, as the user draws in the firing trigger 20, the firing trigger 20 will engage the forward motion stop 107 of the middle handle piece 104, causing the middle handle piece 104 to rotate counter clockwise. Due to the backside shoulder 106 engaging the slotted arm 90, however, the middle handle piece 104 will only be able to rotate counter clockwise as far as the slotted arm 90 permits. In that way, if the motor 65 should stop rotating for some reason, the slotted arm 90 will stop rotating, and the user will not be able to further draw in the firing trigger 20 because the middle handle piece 104 will not be free to rotate counter clockwise due to the slotted arm 90.

[0100] FIGS. 10A and 10B illustrate two states of a variable sensor that may be used as the run motor sensor 110 according to various embodiments of the present invention. The sensor 110 may include a face portion 280, a first electrode (A) 282, a second electrode (B) 284, and a compressible dielectric material 286 between the electrodes 282, 284, such as, for example, an electroactive polymer (EAP). The sensor 110 may be positioned such that the face portion 280 contacts the firing trigger 20 when retracted. Accordingly, when the firing trigger 20 is retracted, the dielectric material 286 is compressed, as shown in FIG. 10B, such that the electrodes 282, 284 are closer together. Since the distance “b” between the electrodes 282, 284 is directly related to the impedance between the electrodes 282, 284, the greater the distance the more impedance, and the closer the distance the less impedance. In that way, the amount that the dielectric 286 is compressed due to retraction of the firing trigger 20 (denoted as force “F” in FIG. 42) is proportional to the impedance between the electrodes 282, 284, which can be used to proportionally control the motor 65.

[0101] Components of an exemplary closure system for closing (or clamping) the anvil 24 of the end effector 12 by retracting the closure trigger 18 are also shown in FIGS. 7-10. In the illustrated embodiment, the closure system includes a yoke 250 connected to the closure trigger 18 by a pivot pin 251 inserted through aligned openings in both the closure trigger 18 and the yoke 250. A pivot pin 252, about which the closure trigger 18 pivots, is inserted through another opening in the closure trigger 18 which is offset from where the pin 251 is inserted through the closure trigger 18. Thus, retraction of the closure trigger 18 causes the upper part of the closure trigger 18, to which the yoke 250 is attached via the pin 251, to rotate counterclockwise. The distal end of the yoke 250 is connected, via a pin 254, to a first closure bracket 256. The first closure bracket 256 connects to a second closure bracket 258. Collectively, the closure brackets 256, 258 define an opening in which the proximate end of the proximate closure tube 40 (see FIG. 4) is seated and held such that longitudinal movement of the closure brackets 256, 258 causes longitudinal motion by the proximate closure tube 40. The instrument 10 also includes a closure rod 260 disposed inside the proximate closure tube 40. The closure rod 260 may include a window 261 into which a post 263 on one of the handle exterior pieces, such as exterior lower side piece 59 in the illustrated embodiment, is disposed to fixedly connect the closure rod 260 to the handle 6. In that way, the proximate closure tube 40 is capable of moving longitudinally relative to the closure rod 260. The closure rod 260 may also include a distal collar 267 that fits into a cavity 269 in proximate spine tube 46 and is retained therein by a cap 271 (see FIG. 4).

[0102] In operation, when the yoke 250 rotates due to retraction of the closure trigger 18, the closure brackets 256, 258 cause the proximate closure tube 40 to move distally (i.e., away from the handle end of the instrument 10), which causes the distal closure tube 42 to move distally, which causes the anvil 24 to rotate about the pivot pins 25 into the clamped or closed position. When the closure trigger 18 is unlocked from the locked position, the proximate closure tube 40 is caused to slide proximately, which causes the distal closure tube 42 to slide proximately, which, by virtue of the tab 27 being inserted in the window 45 of the distal closure tube 42, causes the anvil 24 to pivot about the pivot pins 25 into the open or unclamped position. In that way, by retracting and locking the closure trigger 18, an operator may clamp tissue between the anvil 24 and channel 22, and may unclamp the tissue following the cutting/stapling operation by unlocking the closure trigger 20 from the locked position.

[0103] FIG. 11 is a schematic diagram of an electrical circuit of the instrument 10 according to various embodiments of the present invention. When an operator initially pulls in the firing trigger 20 after locking the closure trigger 18, the sensor 110 is activated, allowing current to flow therethrough. If the normally-open reverse motor sensor switch 130 is open (meaning the end of the end effector stroke has not been reached), current will flow to a single pole, double throw relay 132. Since the reverse motor sensor switch 130 is not closed, the inductor 134 of the relay 132 will not be energized, so the relay 132 will be in its non-energized state. The circuit also includes a cartridge lockout sensor 136. If the end effector 12 includes a staple cartridge 34, the sensor 136 will be in the closed state, allowing current to flow. Otherwise, if the end effector 12 does not include a staple cartridge 34, the sensor 136 will be open, thereby preventing the battery 64 from powering the motor 65.

[0104] When the staple cartridge 34 is present, the sensor 136 is closed, which energizes a single pole, single throw relay 138. When the relay 138 is energized, current flows through the relay 136, through the variable resistor sensor 110, and to the motor 65 via a double pole, double throw relay 140, thereby powering the motor 65 and allowing it to rotate in the forward direction.

[0105] When the end effector 12 reaches the end of its stroke, the reverse motor sensor 130 will be activated, thereby closing the switch 130 and energizing the relay 134. This causes the relay 134 to assume its energized state (not shown in FIG. 11), which causes current to bypass the cartridge lockout sensor 136 and variable resistor 110, and instead causes current to flow to both the normally-closed double pole, double throw relay 142 and back to the motor 65, but in a manner, via the relay 140, that causes the motor 65 to reverse its rotational direction.

[0106] Because the stop motor sensor switch 142 is normally-closed, current will flow back to the relay 134 to keep it closed until the switch 142 opens. When the knife 32 is fully retracted, the stop motor sensor switch 142 is activated, causing the switch 142 to open, thereby removing power from the motor 65.

[0107] In other embodiments, rather than a proportional-type sensor 110, an on-off type sensor could be used. In such embodiments, the rate of rotation of the motor 65 would not be proportional to the force applied by the operator. Rather, the motor 65 would generally rotate at a constant rate. But the operator would still experience force feedback because the firing trigger 20 is geared into the gear drive train.

[0108] In other embodiments, the surgical cutting and fastening instrument 10 may not comprise a run motor sensor 110, reverse motor sensor 130, and/or stop motor sensor 142, as described above. In other embodiments, for example, the surgical instrument 10 may employ an electronic sensor 150 for determining the position of a firing element in the end effector 12 and/or the status or presence of a staple cartridge 34 in the end effector 12. For the purposes of describing the illustrated embodiment, the cutting element 32, sled 33, drive bar 36 and other elements configured to translate in the end effector 12 are collectively referred to herein as firing elements. As shown in FIG. 14, in one form, the electronic sensor 150 comprises a resistive member 152 that is supported within the end effector 12 of the surgical instrument 10. The resistive member 152 can be supported by the staple channel 22, clamping member 20, staple cartridge 34 or another element in the end effector 12. As the firing element translates longitudinally through the end effector 12, the firing element may be in moving contact with the resistive member 152.

[0109] As indicated above, in various embodiments, the resistive member 152 of the electronic sensor 150 is supported by the elongate channel 22. For example, in at least one embodiment, the resistive member 152 is secured to the elongate channel 22 by adhesive. In other embodiments, the resistive member 152 may be fastened to a component in the elongate channel 22. Referring to FIG. 12, the resistive member 152 can be positioned on the interior surface 28 of the staple channel 22 such that a firing element contacts the resistive member 152 as the firing element travels longitudinally through the staple channel 22. In alternative embodiments, the resistive member 152 is supported by or otherwise attached to the staple cartridge 34. Referring to FIG. 13, the resistive member 152 can be supported by the cartridge body 35 of the staple cartridge 34. For example, the resistive member 152 may be attached to a bottom surface of the cartridge body 35 by an appropriate adhesive. In other embodiments, the resistive member 152 may be supported in a slot arrangement (not shown) formed in the bottom surface of the cartridge body 35 or otherwise be retained in position by attachment features formed therein. In the embodiment illustrated in FIG. 13, the resistive member 152 is positioned on the cartridge body 35 of the staple cartridge 34 such that a portion of the firing element contacts the resistive member 152 as the firing element travels longitudinally through the staple channel 22.

[0110] In various embodiments, the resistive member 152 of the electronic sensor 150 comprises a resistor 154 or a plurality of resistors 154. For example, the resistive member 152 can comprise a circuit with a plurality of resistors 154a, 154b, 154c, etc. and a plurality of nodes 156a, 156b, 156c, etc. Referring to FIG. 12, a node 156 can be positioned intermediate each resistor 154. For example, a first node 156a is positioned intermediate a first resistor 154a and a second resistor 154b; a second node 156b is positioned intermediate the second resistor 154b and a third resistor 154c; and a third node 156c is positioned intermediate the third resistor 154c and a fourth resistor 154d; etc. In other words, a node 156 can be positioned between each successive resistor 154 in a circuit in the resistive member 152. The voltage throughout each node 156 is uniform, or substantially uniform. While the resistors 156 are intact, the voltage at each node 156 is different than the voltage at other nodes 156. Referring to FIG. 12, the resistors 154a, 154b, 154c, . . . , 154z can be arranged in a parallel configuration such that the equivalent resistance (R_Eq) of the resistive member 152 can be computed according to:
1/R_Eq=1/R_a+1/R_b+1/R_c+ . . . +1/R_z,
where R_a is the resistance in resistor 154a, R_b is the resistance in resistor 154b, R_c is the resistance in resistor 154c, and R_z is the resistance in the most distal resistor 154z in the resistive member 152. Resistance can be measured in ohms (a). In an alternative embodiment, the resistors 154a, 154b, 154c, . . . , 154z can be arranged in a series configuration such that the equivalent resistance (R_Eq) of the resistive member 152 can be computed according to:
R_Eq=R_a+R_b+R_c+ . . . +R_z.

[0111] As described above, a firing element in end effector 12 is in moving contact with the resistive member 152 as the firing element translates between the proximal end 23a of the staple channel 22 and the distal end 23b of the staple channel 22. In one embodiment, the firing element can slide along a surface of the resistive member 152 as the sled 33 and knife 32 are driven through the elongate channel 22. In another embodiment, the firing element can contact protrusions on the resistive member 152 as the sled 33 and knife 32 are driven through the elongate channel 22. As the firing element translates through the staple channel 22 and movingly contacts the resistive member 152, the resistive member 152 generates output signals indicative of the position of the firing element within the elongate channel 22. The output signals generated by the resistive member 152 can be measurements of voltage (or power) along the resistive member 152. For example, the resistive member 152 could generate a signal indicative of voltage at each node 156 between successive resistors 154.

[0112] In various embodiments, referring to FIG. 12, the firing element can movingly contact the resistive member 152 such that the firing element severs portions of the resistive member 152. For example, the cutting element 32 can traverse through portions of the resistive member 152 as the cutting element 32 travels longitudinally through the elongate channel 22 in response to driving motions applied thereto. In at least one embodiment, for example, the resistive member 152 can be positioned on the interior surface 28 of the elongate channel 22 and oriented such that the resistive member 152 at least partially overlies the slot 30 through the interior surface 28 of the channel 22. As described above, the slot 30 can be configured to receive cutting element 32 when the firing trigger 20 is actuated causing the cutting element 32 and sled 33 to travel longitudinally along the channel 22. For example, the cutting element 32 can travel from a first position at a proximate location along slot 30 to a second position at an intermediate location along slot 30 and from the second position to a third position at a distal location along slot 30. The first position can correspond with a first node 156a, the second position can correspond with another node 156m, and the third position can correspond with another node 156z. As the cutting element 32 travels longitudinally between the nodes along the slot 30, the cutting element 32 severs the tissue clamped between the channel 22 and anvil 20. The cutting element 32 also severs portions of the resistive strip 152 that overlie the portion of slot 30 through which the cutting element 32 translates. Referring again to FIG. 12, the cutting element 32 is positioned intermediate to the proximal end 23a of the elongate channel 22 and the distal end 23b of the channel 22. As shown in that Figure, the cutting element 32 has traversed nodes 156a, 156b, and 156c. Furthermore, the cutting element 32 has severed proximal resistors 154a, 154b, and 154c; however, intermediate and distal resistors 154m, 154n, and 154z, among others, are still intact. It will be understood that, as the cutting element 32 is advanced distally through the staple channel 22 from a starting position to its ultimate ending position therein, the cutting element will have traversed each node 156 and cut each resistor 154 in the resistive member 152 during that firing stroke.

[0113] As the cutting element 32 severs portions of the resistive strip 152, the cutting element can sever resistors 154 arranged along part of a circuit in the resistive member 152. For example, referring to FIG. 12, the cutting element 32 can sever resistor 154a, then resistor 154b, followed by resistor 154c, and so on, until the firing element reaches the distal end 23b of the elongate channel 22. Resistors 154a, 154b, 154c, . . . , 154z. can be arranged in parallel, as shown in FIG. 14. In such an embodiment, the equivalent resistance of the resistor member 152 can increase as each successive resistor is severed by the cutting element 32 according to the relationship:
1/R_Eq=1/R_a+1/R_b+1/R_c+ . . . +1/R_z.
In an alternative embodiment, resistors 154a, 154b, 154c, and so on can be arranged in a series. In such an embodiment, the equivalent resistance of the resistor member 152 can decrease as each successive resistor is severed by the cutting element 32 according to the relationship:
R_Eq=R_a+R_b+R_c+ . . . +R_z.

[0114] Additionally, the voltage across the resistive member 152 can be determined by Ohm's law, which provides:
V=I×R_Eq,
where V represents voltage, I represents current, and R_Eq represents the equivalent resistance. Voltage can be measured in volts (V), current can be measured in amperes (A), and resistance can be measured in ohms (Ω). Assuming a constant current through the resistive member 152, as the equivalent resistance changes with the severance of resistors 154, the voltage in the resistive member correspondingly changes. Accordingly, the position of the cutting element 32 as it translates along the resistive member 152 can be determined from the output signals indicative of voltage generated by the resistive member 152 as the resistors 154 are cut.

[0115] In another embodiment, when the resistive member 152 is supported by the cartridge body 35 of the staple cartridge 34, the cutting element 32 can sever portions of the resistive member 152. Referring to FIG. 13, the resistive member 152 can be positioned on the cartridge body 35 of the staple cartridge 34 and oriented such that the resistive member 152 at least partially overlies a slot 37 through the cartridge body 35. Similar to the above, a slot 37 in the cartridge body 35 can be configured to receive cutting element 32 when the firing trigger 20 is actuated causing the cutting element 32 and sled 33 to travel longitudinally along the channel 22. For example, the cutting element 32 can travel from a first position at a proximate location along slot 37 to a second position at an intermediate location along slot 37 and from the second position to a third position at a distal location along slot 37. As the cutting element 32 travels longitudinally between the plurality of positions along the slot 37, the cutting element 32 severs the tissue clamped between the channel 22 and anvil 20. The cutting element 32 also severs portions of the resistive strip 152 that overlie the portion of slot 37 in the staple cartridge 34 through which the cutting element 32 translates. Similar to the above, as the cutting element cuts resistors 154 in the resistive member 152, the equivalent resistance in the resistive member 152 changes, which results in a corresponding change in voltage across the resistive member 152.

[0116] In various embodiments, referring to FIG. 3, the staple channel 22 may include a contact pad, portion, point, or surface 158. The contact pad 158 can be positioned on the interior surface 28 of the staple channel 22. In various embodiments, when the resistive member 152 is positioned on the cartridge body 35 of the staple cartridge 34 (FIG. 14), the contact pad 158 in the channel 22 can be configured to contact a portion of the resistive member 152. The contact pad 158 can contact a circuit of the resistive member 152, a wire 168 extending from the resistive member 152, or a contact pad operably engaged with the resistive member. Further, the contact pad 158 can communicate with the conductive members 170, 172 and/or the memory device 160 via a wired or wireless connection, as described in greater detail below.

[0117] The surgical instrument also comprises a memory device 160 that operably communicates with the resistive member 152 of the electronic sensor 150. See FIG. 1. Directly or indirectly, the resistive member 152 provides a signal to the memory device 160, which records the signal as described in more detail below. The memory device 160 can be integrated into the electronic sensor 150. In another embodiment, the memory device 160 can be external to the electronic sensor and can be positioned near the resistive member 152, such as in the elongate channel 22 of the end effector 12. In other embodiments, referring to FIG. 1, the memory device 160 can be positioned farther from the resistive member 152, such as in the handle 6 of the instrument 10. The memory device 160 may be any kind of device capable of storing or recording sensor signals. For example, the memory device 160 may include a microprocessor, an Electrically Erasable Programmable Read Only Memory (EEPROM), or any other suitable storage device. The memory device 160 may record the signals provided by the resistive member 152 in any suitable way. For example, in one embodiment, the memory device 160 may record the signal from the resistive member 152 when that signal changes, such as when the cutting element 32 severs a resistor 154 in the resistive member 152 resulting in a change in the equivalent resistance and a corresponding change in the voltage across the resistive member 152. In another embodiment, the memory device 160 may record the state of the resistive member 152 and signals from other sensors, such as the run motor sensor 110, reverse motor sensor 130, and/or stop motor sensor 142 in the surgical instrument 10, when the signal from any sensor changes states. This may provide a snap-shot of the state of the instrument 10. In various embodiments, the memory device 160 and/or sensor(s) may be implemented to include 1-WIRE bus products available from DALLAS SEMICONDUCTOR such as, for example, a 1-WIRE EEPROM.

[0118] In various embodiments, the memory device 160 is externally accessible, allowing an outside device, such as a computer, to access the instrument conditions recorded by the memory device 160. For example, the memory device 160 may include a data port 162. The data port 162 may provide the stored instrument conditions according to any wired or wireless communication protocol in, for example, serial or parallel format. The memory device 160 may also include a removable medium 164 in addition to or instead of the output port 162. The removable medium 164 may be any kind of suitable data storage device that can be removed from the instrument 10. For example, the removable medium 164 may include any suitable kind of flash memory, such as a Personal Computer Memory Card International Association (PCMCIA) card, a COMPACTFLASH card, a MULTIMEDIA card, a FLASHMEDIA card, etc. The removable medium 164 may also include any suitable kind of disk-based storage including, for example, a portable hard drive, a compact disk (CD), a digital video disk (DVD), etc.

[0119] The output from the resistive member 152 may be provided to the memory device 160, for example, via an analog-to-digital converter (not shown). In various embodiments, output signals from the resistive member 152 may first be transmitted to an integrated circuit (not shown) for amplification of the signal. Further, the output may be encoded and/or modulated according to a modulation scheme.

[0120] The output from the electronic sensor 150 may be provided to the memory device 160 by a wired communication. Referring to FIG. 1, insulated wires or similar conductors 168 may transmit an electrical signal indicative of the position of the firing element in the end effector 12 to the memory device 160. The wires 168 may be made of an electrically conductive polymer and/or metal (e.g. copper) and may be sufficiently flexible to pass through an articulation pivot 14 and not be damaged by articulation.

[0121] In another embodiment, the signal may be wirelessly transmitted to the memory device 160. Various wireless communication embodiments are described in U.S. patent application Ser. No. 13/118,259 to James R. Giordano et al. filed on May 27, 2011, the disclosure of which is herein incorporated by reference in its entirety. Referring to FIG. 12, to wirelessly transmit the signal, the resistive member 152 may comprise a conductive element 170 that acts as a transmitting antenna. The conductive element 170 may both transmit signals from the resistive member 152 and receive power from a power source, such as a battery, external or internal to the surgical instrument 10. The conductive element 170 of the resistive member 152 is preferably insulated from the electrically conductive outer shaft 8 of the instrument 10.

[0122] In another embodiment, the conductive element 170 may comprise components of the end effector 12 and shaft 8. In such an embodiment, the resistive member 152 is electrically connected to the shaft 8 and the memory device is insulated from the shaft. For example, the interior surface 30 of the elongate channel 22 may comprise a conductive material, which in turn may be electrically coupled to conductive elements of the shaft 8 (such as closure tubes 40, 42) by either direct or indirect electrical contact. The shaft 8 may be grounded by the exterior lower and upper side pieces 59-62, which may be made of non-electrically conductive material, such as plastic. Additional components of the end effector 12 may comprise non-conductive material and the memory device 160 is insulated from the shaft 8. The components of the end effector 12 and shaft 8 electrically connected to the conductive element 170 of the sensor 150 may serve as part of an antenna for transmitting signals indicative from the resistive member 152 to the memory device 160. Alternatively, the memory device 160 may be in electrical communication with select components of the end effector 12 and shaft 8 and the resistive member 152 may be insulated. The select components of the end effector 12 and shaft electrically connected to the memory device 160 may serve as part of an antenna for receiving signals from the sensor 150. The resistive member 152 may be insulated by positioning it on the interior surface 28 of the elongate channel 22, which is made of a non-electrically conductive material, such as plastic.

[0123] The surgical instrument 10 may comprise multiple conductive elements for transmitting signals from the resistive member 152 to the memory device 160. For example, referring again to FIG. 12, the resistive member 152 may transmit a signal to a conductive element 170. The signal may be transmitted by an insulated wire 168. Such an intermediate conductive element 170 could be located, for example, in the end effector 12, along the shaft 8, or on the handle 6 of the instrument 10. The conductive element 170 may relay the signal to a distal intermediate conductive element 172a, which may then relay the signal to a proximal intermediate conductive element 172b or to the memory device 160 (shown in diagrammatic form in FIG. 1). If more conductive couplings are in place between the resistive member 152 and the memory device 160, the distance between the conductive elements 170, 172 may be reduced and a weaker signal may be utilized to transmit the signal. Alternatively, if fewer conductive couplings are in place, a stronger signal may be required due to the greater transmission distances. Because the distances between the conductive elements 170, 172 can be fixed and known, the power levels could be optimized for low levels to thereby minimize interference with other systems in the environment of the instrument 10.

[0124] Alternatively, a combination of wired and wireless connections could be utilized to transmit signals from the resistive member 152 to the memory device 160. For example, referring to FIG. 1, the end effector 12 may include a wire 168 that connects the resistive member 152 to a distal intermediate conductive element 172a on the shaft 6 of the instrument. The signal may then be wirelessly transmitted from the distal intermediate conductive element 172a to a proximal intermediate conductive element 172b. The proximal intermediate conductive element 172b may transmit the signal to the memory device 160 via a conductive wire 168 or wirelessly.

[0125] The resistive member 152 may communicate with the memory device 160 using any suitable frequency (e.g., an ISM band). Also, the resistive member 152 may transmit signals at a different frequency range than the frequency range of the received signals from the memory device 160. Also, though only one antenna is discussed above with regard to electronic sensor 150, in other embodiments the electronic sensor 150 may comprise separate receiving and transmitting antennas.

[0126] The surgical instrument 10 can also comprise a processor 180 that operably interfaces with the memory device 160. Referring to FIG. 1, the processor 180 and memory device 160 can comprise an integral component. In another embodiment, the processor 180 and memory device 160 are discrete components of the surgical instrument. The processor 180 determines the position of the firing element in the end effector 12 from the output from the resistive member 152. In one embodiment, the processor 180 computes the position of the cutting element 32 in the end effector 12 from signals indicative of voltage from the resistive member 152. For example, if the resistors 154 of the resistive strip 152 are connected in parallel, the equivalent resistance of the resistive member 152 increases as each successive resistor 154 is cut. The corresponding changes in voltage across the resistive member 152 indicates the nodal position of the cutting element 32 along the resistive strip 152, which further corresponds to the location of the cutting element 32 in the elongate channel 22.

[0127] Upon determining the position of the firing element in the elongate channel 22, the position may be communicated to an indicator that indicates the position of the firing element. The indicator may be a visual indication screen 190 on the handle 6 of the instrument viewable by the user. Additionally or alternatively, the position may be communicated to the user by a haptic indication. For example, as the knife 32 reaches the end of the slot 30 in the staple channel 22, the user may be alerted by increased resistance from the firing trigger 20. In another embodiment, referring to FIG. 7, the user may be alerted by vibrations in the pistol grip 26 of the instrument 10 by a vibrating element 192 operably communicating with the processor 180.

[0128] The unique and novel aspects of the various embodiments of the present disclosure utilize an electronic sensor to determine the position of a firing element in the end effector of a surgical instrument and/or the status of a staple cartridge in the end effector. Thus, the unique arrangements and principles of various embodiments of the present disclosure may enable a variety of different forms of the electronic sensor disclosed and claimed herein to be effectively employed in connection with other types and forms of surgical instruments, end effectors and staple cartridges used in conjunction with a firing element. The foregoing discussion describes a motor-driven, power-assist surgical cutting and fastening instrument according to some embodiments of the present disclosure. However, as previously stated, those of ordinary skill in the art will appreciate that a surgical instrument according to various embodiments of the present disclosure may be powered and controlled in an alternative manner, such as by manual force or robotic controls. For example, the end effector 12 described above, may be powered and controlled by a robotic system, such as robotic system 1000 described in greater detail below.

[0129] FIG. 15 depicts one version of a master controller 1001 that may be used in connection with a robotic arm slave cart 1100 of the type depicted in FIG. 16. Master controller 1001 and robotic arm slave cart 1100, as well as their respective components and control systems are collectively referred to herein as a robotic system 1000. Examples of such systems and devices are disclosed in U.S. Pat. No. 7,524,320, issued Apr. 28, 2009, entitled “Mechanical Actuator Interface System for Robotic Surgical Tools” by Michael J. Tierney et al., which has been herein incorporated by reference. Thus, various details of such devices will not be described in detail herein beyond that which may be necessary to understand various embodiments and forms of the present invention. As is known, the master controller 1001 generally includes a control system (generally represented as 1003 in FIG. 15) which are grasped by the surgeon and manipulated in space while the surgeon views the procedure via a stereo display 1002. The master controllers 1001 generally comprise manual input devices which preferably move with multiple degrees of freedom, and which often further have an actuatable handle for actuating tools (for example, for closing grasping jaws, applying an electrical potential to an electrode, or the like). Various robotic controller arrangements and surgical tool arrangements are disclosed in U.S. patent application Ser. No. 13/118,241 entitled “Surgical Stapling Instruments with Rotatable Staple Deployment Arrangements,” the full disclosure of which is herein incorporated by reference.

[0130] As can be seen in FIG. 16, in one form, the robotic arm cart 1100 is configured to actuate a plurality of surgical tools, generally designated as 1200. Various robotic surgery systems and methods employing master controller and robotic arm cart arrangements are disclosed in U.S. Pat. No. 6,132,368, entitled “Multi-Component Telepresence System and Method”, the full disclosure of which is incorporated herein by reference. In various forms, the robotic arm cart 1100 includes a base 1102 from which, in the illustrated embodiment, three surgical tools 1200 are supported. In various forms, the surgical tools 1200 are each supported by a series of manually articulatable linkages, generally referred to as set-up joints 1104, and a robotic manipulator 1106. These structures are herein illustrated with protective covers extending over much of the robotic linkage. These protective covers may be optional, and may be limited in size or entirely eliminated in some embodiments to minimize the inertia that is encountered by the servo mechanisms used to manipulate such devices, to limit the volume of moving components so as to avoid collisions, and to limit the overall weight of the cart 1100. Cart 1100 will generally have dimensions suitable for transporting the cart 1100 between operating rooms. The cart 1100 may be configured to typically fit through standard operating room doors and onto standard hospital elevators. In various forms, the cart 1100 would preferably have a weight and include a wheel (or other transportation) system that allows the cart 1100 to be positioned adjacent an operating table by a single attendant.

[0131] Referring now to FIG. 17, in at least one form, robotic manipulators 1106 may include a linkage 1108 that constrains movement of the surgical tool 1200. In various embodiments, linkage 1108 includes rigid links coupled together by rotational joints in a parallelogram arrangement so that the surgical tool 1200 rotates around a point in space 1110, as more fully described in issued U.S. Pat. No. 5,817,084, the full disclosure of which is herein incorporated by reference. The parallelogram arrangement constrains rotation to pivoting about an axis 1112a, sometimes called the pitch axis. The links supporting the parallelogram linkage are pivotally mounted to set-up joints 1104 (FIG. 15) so that the surgical tool 1200 further rotates about an axis 1112b, sometimes called the yaw axis. The pitch and yaw axes 1112a, 1112b intersect at the remote center 1114, which is aligned along a shaft 1208 of the surgical tool 1200. The surgical tool 1200 may have further degrees of driven freedom as supported by manipulator 1106, including sliding motion of the surgical tool 1200 along the longitudinal tool axis “LT-LT”. As the surgical tool 1200 slides along the tool axis LT-LT relative to manipulator 1106 (arrow 1112c), remote center 1114 remains fixed relative to base 1116 of manipulator 1106. Hence, the entire manipulator is generally moved to re-position remote center 1114. Linkage 1108 of manipulator 1106 is driven by a series of motors 1120. These motors actively move linkage 1108 in response to commands from a processor of a control system. As will be discussed in further detail below, motors 1120 are also employed to manipulate the surgical tool 1200.

[0132] An alternative set-up joint structure is illustrated in FIG. 18. In this embodiment, a surgical tool 1200 is supported by an alternative manipulator structure 1106′ between two tissue manipulation tools. Those of ordinary skill in the art will appreciate that various embodiments of the present invention may incorporate a wide variety of alternative robotic structures, including those described in U.S. Pat. No. 5,878,193, entitled “Automated Endoscope System For Optimal Positioning”, the full disclosure of which is incorporated herein by reference. Additionally, while the data communication between a robotic component and the processor of the robotic surgical system is primarily described herein with reference to communication between the surgical tool 1200 and the master controller 1001, it should be understood that similar communication may take place between circuitry of a manipulator, a set-up joint, an endoscope or other image capture device, or the like, and the processor of the robotic surgical system for component compatibility verification, component-type identification, component calibration (such as off-set or the like) communication, confirmation of coupling of the component to the robotic surgical system, or the like.

[0133] An exemplary non-limiting surgical tool 1200 that is well-adapted for use with a robotic system 1000 that has a tool drive assembly 1010 (FIG. 20) that is operatively coupled to a master controller 1001 that is operable by inputs from an operator (i.e., a surgeon) is depicted in FIG. 19. As can be seen in that Figure, the surgical tool 1200 includes a surgical end effector 2012 that comprises an endocutter. In at least one form, the surgical tool 1200 generally includes an elongated shaft assembly 2008 that has a proximal closure tube 2040 and a distal closure tube 2042 that are coupled together by an articulation joint 2011. The surgical tool 1200 is operably coupled to the manipulator by a tool mounting portion, generally designated as 1300. The surgical tool 1200 further includes an interface 1230 which mechanically and electrically couples the tool mounting portion 1300 to the manipulator. One form of interface 1230 is illustrated in FIGS. 20-24. In various embodiments, the tool mounting portion 1300 includes a tool mounting plate 1302 that operably supports a plurality of (four are shown in FIG. 24) rotatable body portions, driven discs or elements 1304, that each include a pair of pins 1306 that extend from a surface of the driven element 1304. One pin 1306 is closer to an axis of rotation of each driven elements 1304 than the other pin 1306 on the same driven element 1304, which helps to ensure positive angular alignment of the driven element 1304. Interface 1230 includes an adaptor portion 1240 that is configured to mountingly engage the mounting plate 1302 as will be further discussed below. The adaptor portion 1240 may include an array of electrical connecting pins 1242 (FIG. 22) which may be coupled to a memory structure by a circuit board within the tool mounting portion 1300. While interface 1230 is described herein with reference to mechanical, electrical, and magnetic coupling elements, it should be understood that a wide variety of telemetry modalities might be used, including infrared, inductive coupling, or the like.

[0134] As can be seen in FIGS. 20-23, the adapter portion 1240 generally includes a tool side 1244 and a holder side 1246. In various forms, a plurality of rotatable bodies 1250 are mounted to a floating plate 1248 which has a limited range of movement relative to the surrounding adaptor structure normal to the major surfaces of the adaptor 1240. Axial movement of the floating plate 1248 helps decouple the rotatable bodies 1250 from the tool mounting portion 1300 when the levers 1303 along the sides of the tool mounting portion housing 1301 are actuated (See FIG. 19). Other mechanisms/arrangements may be employed for releasably coupling the tool mounting portion 1300 to the adaptor 1240. In at least one form, rotatable bodies 1250 are resiliently mounted to floating plate 1248 by resilient radial members which extend into a circumferential indentation about the rotatable bodies 1250. The rotatable bodies 1250 can move axially relative to plate 1248 by deflection of these resilient structures. When disposed in a first axial position (toward tool side 1244) the rotatable bodies 1250 are free to rotate without angular limitation. However, as the rotatable bodies 1250 move axially toward tool side 1244, tabs 1252 (extending radially from the rotatable bodies 1250) laterally engage detents on the floating plates so as to limit angular rotation of the rotatable bodies 1250 about their axes. This limited rotation can be used to help drivingly engage the rotatable bodies 1250 with drive pins 1272 of a corresponding tool holder portion 1270 of the robotic system 1000, as the drive pins 1272 will push the rotatable bodies 1250 into the limited rotation position until the pins 1234 are aligned with (and slide into) openings 1256′. Openings 1256 on the tool side 1244 and openings 1256′ on the holder side 1246 of rotatable bodies 1250 are configured to accurately align the driven elements 1304 (FIG. 24) of the tool mounting portion 1300 with the drive elements 1271 of the tool holder 1270. As described above regarding inner and outer pins 1306 of driven elements 1304, the openings 1256, 1256′ are at differing distances from the axis of rotation on their respective rotatable bodies 1250 so as to ensure that the alignment is not 180 degrees from its intended position. Additionally, each of the openings 1256 is slightly radially elongated so as to fittingly receive the pins 1306 in the circumferential orientation. This allows the pins 1306 to slide radially within the openings 1256, 1256′ and accommodate some axial misalignment between the tool 1200 and tool holder 1270, while minimizing any angular misalignment and backlash between the drive and driven elements. Openings 1256 on the tool side 1244 are offset by about 90 degrees from the openings 1256′ (shown in broken lines) on the holder side 1246, as can be seen most clearly in FIG. 23.

[0135] Various embodiments may further include an array of electrical connector pins 1242 located on holder side 1246 of adaptor 1240, and the tool side 1244 of the adaptor 1240 may include slots 1258 (FIG. 23) for receiving a pin array (not shown) from the tool mounting portion 1300. In addition to transmitting electrical signals between the surgical tool 1200 and the tool holder 1270, at least some of these electrical connections may be coupled to an adaptor memory device 1260 (FIG. 22) by a circuit board of the adaptor 1240.

[0136] A detachable latch arrangement 1239 may be employed to releasably affix the adaptor 1240 to the tool holder 1270. As used herein, the term “tool drive assembly” when used in the context of the robotic system 1000, at least encompasses various embodiments of the adapter 1240 and tool holder 1270 and which has been generally designated as 1010 in FIG. 20. For example, as can be seen in FIG. 20, the tool holder 1270 may include a first latch pin arrangement 1274 that is sized to be received in corresponding clevis slots 1241 provided in the adaptor 1240. In addition, the tool holder 1270 may further have second latch pins 1276 that are sized to be retained in corresponding latch clevises 1243 in the adaptor 1240. In at least one form, a latch assembly 1245 is movably supported on the adapter 1240 and is biasable between a first latched position wherein the latch pins 1276 are retained within their respective latch clevis 1243 and an unlatched position wherein the second latch pins 1276 may be into or removed from the latch clevises 1243. A spring or springs (not shown) are employed to bias the latch assembly into the latched position. A lip on the tool side 1244 of adaptor 1240 may slidably receive laterally extending tabs of tool mounting housing 1301.

[0137] Turning next to FIGS. 24-31, in at least one embodiment, the surgical tool 1200 includes a surgical end effector 2012 that comprises in this example, among other things, at least one component 2024 that is selectively movable between first and second positions relative to at least one other component 2022 in response to various control motions applied thereto as will be discussed in further detail below. In various embodiments, component 2022 comprises an elongated channel 2022 configured to operably support a surgical staple cartridge 2034 therein and component 2024 comprises a pivotally translatable clamping member, such as an anvil 2024. Various embodiments of the surgical end effector 2012 are configured to maintain the anvil 2024 and elongated channel 2022 at a spacing that assures effective stapling and severing of tissue clamped in the surgical end effector 2012. As can be seen in FIG. 30, the surgical end effector 2012 further includes a cutting instrument 2032 and a sled 2033. The cutting instrument 2032 may be, for example, a knife. The surgical staple cartridge 2034 operably houses a plurality of surgical staples (not show) therein that are supported on movable staple drivers (not shown). As the cutting instrument 2032 is driven distally through a centrally-disposed slot (not shown) in the surgical staple cartridge 2034, it forces the sled 2033 distally as well. As the sled 2033 is driven distally, its “wedge-shaped” configuration contacts the movable staple drivers and drives them vertically toward the closed anvil 2024. The surgical staples are formed as they are driven into the forming surface located on the underside of the anvil 2024. The sled 2033 may be part of the surgical staple cartridge 2034, such that when the cutting instrument 2032 is retracted following the cutting operation, the sled 2033 does not retract. The anvil 2024 may be pivotably opened and closed at a pivot point 2025 located at the proximal end of the elongated channel 2022. The anvil 2024 may also include a tab 2027 at its proximal end that interacts with a component of the mechanical closure system (described further below) to facilitate the opening of the anvil 2024. The elongated channel 2022 and the anvil 2024 may be made of an electrically conductive material (such as metal) so that they may serve as part of an antenna that communicates with sensor(s) in the end effector, as described above. The surgical staple cartridge 2034 could be made of a nonconductive material (such as plastic) and the sensor(s) may be connected to or disposed in the surgical staple cartridge 2034, as was also described above.

[0138] As can be seen in FIGS. 24-31, the surgical end effector 2012 is attached to the tool mounting portion 1300 by an elongated shaft assembly 2008 according to various embodiments. As shown in the illustrated embodiment, the shaft assembly 2008 includes an articulation joint generally indicated as 2011 that enables the surgical end effector 2012 to be selectively articulated about an articulation axis AA-AA that is substantially transverse to a longitudinal tool axis LT-LT. See FIG. 25. In other embodiments, the articulation joint is omitted. In various embodiments, the shaft assembly 2008 may include a closure tube assembly 2009 that comprises a proximal closure tube 2040 and a distal closure tube 2042 that are pivotably linked by a pivot links 2044 and operably supported on a spine assembly generally depicted as 2049. In the illustrated embodiment, the spine assembly 2049 comprises a distal spine portion 2050 that is attached to the elongated channel 2022 and is pivotally coupled to the proximal spine portion 2052. The closure tube assembly 2009 is configured to axially slide on the spine assembly 2049 in response to actuation motions applied thereto. The distal closure tube 2042 includes an opening 2045 into which the tab 2027 on the anvil 2024 is inserted in order to facilitate opening of the anvil 2024 as the distal closure tube 2042 is moved axially in the proximal direction “PD”. The closure tubes 2040, 2042 may be made of electrically conductive material (such as metal) so that they may serve as part of the antenna, as described above. Components of the main drive shaft assembly (e.g., the drive shafts 2048, 2050) may be made of a nonconductive material (such as plastic).

[0139] In use, it may be desirable to rotate the surgical end effector 2012 about the longitudinal tool axis LT-LT. In at least one embodiment, the tool mounting portion 1300 includes a rotational transmission assembly 2069 that is configured to receive a corresponding rotary output motion from the tool drive assembly 1010 of the robotic system 1000 and convert that rotary output motion to a rotary control motion for rotating the elongated shaft assembly 2008 (and surgical end effector 2012) about the longitudinal tool axis LT-LT. In various embodiments, for example, the proximal end 2060 of the proximal closure tube 2040 is rotatably supported on the tool mounting plate 1302 of the tool mounting portion 1300 by a forward support cradle 1309 and a closure sled 2100 that is also movably supported on the tool mounting plate 1302. In at least one form, the rotational transmission assembly 2069 includes a tube gear segment 2062 that is formed on (or attached to) the proximal end 2060 of the proximal closure tube 2040 for operable engagement by a rotational gear assembly 2070 that is operably supported on the tool mounting plate 1302. As can be seen in FIG. 27, the rotational gear assembly 2070, in at least one embodiment, comprises a rotation drive gear 2072 that is coupled to a corresponding first one of the driven discs or elements 1304 on the adapter side 1307 of the tool mounting plate 1302 when the tool mounting portion 1300 is coupled to the tool drive assembly 1010. See FIG. 24. The rotational gear assembly 2070 further comprises a rotary driven gear 2074 that is rotatably supported on the tool mounting plate 1302 in meshing engagement with the tube gear segment 2062 and the rotation drive gear 2072. Application of a first rotary output motion from the tool drive assembly 1010 of the robotic system 1000 to the corresponding driven element 1304 will thereby cause rotation of the rotation drive gear 2072. Rotation of the rotation drive gear 2072 ultimately results in the rotation of the elongated shaft assembly 2008 (and the surgical end effector 2012) about the longitudinal tool axis LT-LT (represented by arrow “R” in FIG. 27). It will be appreciated that the application of a rotary output motion from the tool drive assembly 1010 in one direction will result in the rotation of the elongated shaft assembly 2008 and surgical end effector 2012 about the longitudinal tool axis LT-LT in a first direction and an application of the rotary output motion in an opposite direction will result in the rotation of the elongated shaft assembly 2008 and surgical end effector 2012 in a second direction that is opposite to the first direction.

[0140] In at least one embodiment, the closure of the anvil 2024 relative to the staple cartridge 2034 is accomplished by axially moving the closure tube assembly 2009 in the distal direction “DD” on the spine assembly 2049. As indicated above, in various embodiments, the proximal end 2060 of the proximal closure tube 2040 is supported by the closure sled 2100 which comprises a portion of a closure transmission, generally depicted as 2099. In at least one form, the closure sled 2100 is configured to support the closure tube 2009 on the tool mounting plate 1320 such that the proximal closure tube 2040 can rotate relative to the closure sled 2100, yet travel axially with the closure sled 2100. In particular, as can be seen in FIG. 32, the closure sled 2100 has an upstanding tab 2101 that extends into a radial groove 2063 in the proximal end portion of the proximal closure tube 2040. In addition, as can be seen in FIGS. 29 and 32, the closure sled 2100 has a tab portion 2102 that extends through a slot 1305 in the tool mounting plate 1302. The tab portion 2102 is configured to retain the closure sled 2100 in sliding engagement with the tool mounting plate 1302. In various embodiments, the closure sled 2100 has an upstanding portion 2104 that has a closure rack gear 2106 formed thereon. The closure rack gear 2106 is configured for driving engagement with a closure gear assembly 2110. See FIG. 29.

[0141] In various forms, the closure gear assembly 2110 includes a closure spur gear 2112 that is coupled to a corresponding second one of the driven discs or elements 1304 on the adapter side 1307 of the tool mounting plate 1302. See FIG. 24. Thus, application of a second rotary output motion from the tool drive assembly 1010 of the robotic system 1000 to the corresponding second driven element 1304 will cause rotation of the closure spur gear 2112 when the tool mounting portion 1300 is coupled to the tool drive assembly 1010. The closure gear assembly 2110 further includes a closure reduction gear set 2114 that is supported in meshing engagement with the closure spur gear 2112. As can be seen in FIGS. 28 and 29, the closure reduction gear set 2114 includes a driven gear 2116 that is rotatably supported in meshing engagement with the closure spur gear 2112. The closure reduction gear set 2114 further includes a first closure drive gear 2118 that is in meshing engagement with a second closure drive gear 2120 that is rotatably supported on the tool mounting plate 1302 in meshing engagement with the closure rack gear 2106. Thus, application of a second rotary output motion from the tool drive assembly 1010 of the robotic system 1000 to the corresponding second driven element 1304 will cause rotation of the closure spur gear 2112 and the closure transmission 2110 and ultimately drive the closure sled 2100 and closure tube assembly 2009 axially. The axial direction in which the closure tube assembly 2009 moves ultimately depends upon the direction in which the second driven element 1304 is rotated. For example, in response to one rotary output motion received from the tool drive assembly 1010 of the robotic system 1000, the closure sled 2100 will be driven in the distal direction “DD” and ultimately drive the closure tube assembly 1009 in the distal direction. As the distal closure tube 2042 is driven distally, the end of the closure tube segment 2042 will engage a portion of the anvil 2024 and cause the anvil 2024 to pivot to a closed position. Upon application of an “opening” out put motion from the tool drive assembly 1010 of the robotic system 1000, the closure sled 2100 and shaft assembly 2008 will be driven in the proximal direction “PD”. As the distal closure tube 2042 is driven in the proximal direction, the opening 2045 therein interacts with the tab 2027 on the anvil 2024 to facilitate the opening thereof. In various embodiments, a spring (not shown) may be employed to bias the anvil to the open position when the distal closure tube 2042 has been moved to its starting position. In various embodiments, the various gears of the closure gear assembly 2110 are sized to generate the necessary closure forces needed to satisfactorily close the anvil 2024 onto the tissue to be cut and stapled by the surgical end effector 2012. For example, the gears of the closure transmission 2110 may be sized to generate approximately 70-120 pounds.

[0142] In various embodiments, the cutting instrument 2032 is driven through the surgical end effector 2012 by a knife bar 2200. See FIGS. 30 and 32. In at least one form, the knife bar 2200 may be fabricated from, for example, stainless steel or other similar material and has a substantially rectangular cross-sectional shape. Such knife bar configuration is sufficiently rigid to push the cutting instrument 2032 through tissue clamped in the surgical end effector 2012, while still being flexible enough to enable the surgical end effector 2012 to articulate relative to the proximal closure tube 2040 and the proximal spine portion 2052 about the articulation axis AA-AA as will be discussed in further detail below. As can be seen in FIGS. 33 and 34, the proximal spine portion 2052 has a rectangular-shaped passage 2054 extending therethrough to provide support to the knife bar 2200 as it is axially pushed therethrough. The proximal spine portion 2052 has a proximal end 2056 that is rotatably mounted to a spine mounting bracket 2057 attached to the tool mounting plate 1032. See FIG. 32. Such arrangement permits the proximal spine portion 2052 to rotate, but not move axially, within the proximal closure tube 2040.

[0143] As shown in FIG. 30, the distal end 2202 of the knife bar 2200 is attached to the cutting instrument 2032. The proximal end 2204 of the knife bar 2200 is rotatably affixed to a knife rack gear 2206 such that the knife bar 2200 is free to rotate relative to the knife rack gear 2206. See FIG. 32. As can be seen in FIGS. 26-31, the knife rack gear 2206 is slidably supported within a rack housing 2210 that is attached to the tool mounting plate 1302 such that the knife rack gear 2206 is retained in meshing engagement with a knife gear assembly 2220. More specifically and with reference to FIG. 29, in at least one embodiment, the knife gear assembly 2220 includes a knife spur gear 2222 that is coupled to a corresponding third one of the driven discs or elements 1304 on the adapter side 1307 of the tool mounting plate 1302. See FIG. 24. Thus, application of another rotary output motion from the robotic system 1000 through the tool drive assembly 1010 to the corresponding third driven element 1304 will cause rotation of the knife spur gear 2222. The knife gear assembly 2220 further includes a knife gear reduction set 2224 that includes a first knife driven gear 2226 and a second knife drive gear 2228. The knife gear reduction set 2224 is rotatably mounted to the tool mounting plate 1302 such that the first knife driven gear 2226 is in meshing engagement with the knife spur gear 2222. Likewise, the second knife drive gear 2228 is in meshing engagement with a third knife drive gear 2230 that is rotatably supported on the tool mounting plate 1302 in meshing engagement with the knife rack gear 2206. In various embodiments, the gears of the knife gear assembly 2220 are sized to generate the forces needed to drive the cutting element 2032 through the tissue clamped in the surgical end effector 2012 and actuate the staples therein. For example, the gears of the knife drive assembly 2230 may be sized to generate approximately 40 to 100 pounds. It will be appreciated that the application of a rotary output motion from the tool drive assembly 1010 in one direction will result in the axial movement of the cutting instrument 2032 in a distal direction and application of the rotary output motion in an opposite direction will result in the axial travel of the cutting instrument 2032 in a proximal direction.

[0144] FIG. 35 illustrates another end effector 2012 that includes an electronic sensor 2150. The electronic sensor 2150, similar to sensor 150 described in above, determines the position of a firing element in the end effector 2012 and/or the status or presence of a staple cartridge 2034 in the end effector 2012. The cutting element 2032, sled 2033, knife bar 2200 and other elements configured to translate in the end effector 2012 are collectively referred to herein as firing elements. In at least one form, the electronic sensor 2150 comprises a resistive member 2152 that is supported within the end effector 2012 of the surgical tool 1200. The resistive member 2152 can be supported by the staple channel 2022, clamping member 2024, staple cartridge 2034 or another element in the end effector 2012. As a firing element translates longitudinally through the end effector 2012, the firing element may be in moving contact with the resistive member 2152.

[0145] In various embodiments, the resistive member 2152 of the electronic sensor 2150 is supported by the elongate channel 2022. For example, in at least one form, the resistive member 2152 is secured to the resistive member 2152 in the elongate channel 2022 by adhesive. In other embodiments, the resistive member 2152 may be fastened to a component in the elongate channel 2022. Referring one embodiment shown in FIG. 35, the resistive member 2152 is positioned on the interior surface 2028 of the staple channel 2022 such that a firing element contacts the resistive member 2152 as the firing element travels longitudinally through the staple channel 2022. In alternative embodiments, the resistive member 2152 is supported by the staple cartridge 2034. Referring to FIG. 36, the resistive member 2152 can be supported by the cartridge body 2035 of the staple cartridge 2034. Similar to the above, the resistive member 2152 can be positioned on the cartridge body 2035 of the staple cartridge 2034 such that at least a portion of the firing element contacts the resistive member 2152 as the firing element travels longitudinally through the staple channel 2022.

[0146] As described above with respect to resistive member 152, resistive member 2152 of the electronic sensor 2150 can comprise a plurality of resistors 2154 and a plurality of nodes 2156. The resistors 2154 can be arranged in a parallel configuration or may be arranged in a series. Referring to FIG. 35, a firing element in the end effector 2012 is in moving contact with the resistive member 2152 as the firing element translates between the proximal end 2023a of the staple channel 2022 and the distal end 2023b of the staple channel 2022. As the firing element translates through the staple channel 2022 and movingly contacts the resistive member 2152, the resistive member 2152 generates output signals indicative of the position of the firing element within the elongate channel 22. The output signals generated by the resistive member 2152 can be measurements of voltage (or power) along the resistive member 2152.

[0147] In various embodiments, referring to FIG. 35, the firing element can movingly contact the resistive member 2152 such that the firing element severs portions of the resistive member 2152, as described in greater detail above with regards to resistive member 152. Accordingly, the position of the cutting element 32 as it translates along the resistive member 2152 can be determined from the output signals indicative of voltage generated by the resistive member 2152 as the resistors 2154 are cut.

[0148] The robotics system 1000 can also comprise a processor 2180 that operably interfaces with the master controller 1001. In various embodiments, the processor 2180 can be integrated into the master controller 1001. As described in greater detail above with respect to processor 180, processor 2180 can determine the position of the firing element in the end effector 12 from the output signals from the sensor 2150. Directly or indirectly, the sensor 2150 can provide a signal to the processor 2180, as described in greater detail above. In various embodiments, the processor 2180 may comprise a memory device 2160. As described in greater detail above with regards to memory device 160, memory device 2160 may be any kind of device capable of storing or recording sensor signals and may communicate with the resistive member 2152 of the sensor 2150 by a wired or wireless communication or a combination thereof via wires 168, conductive elements 170, and contact pads 158 (FIG. 3). In other embodiments, the memory device 2160 may not be integrated into the processor 2180; the memory device may be a discrete component of the robotics system 1000 that operably communicates with the resistive member 2152 of the sensor 2150 and then relays output signals from sensor 2150 to the processor 2180.

[0149] If the processor 2180 is not integrated into the master controller 1001, the processor 2180 may communicate the position of the firing element to the master controller 1001. Upon determining the position of the firing element in the elongate channel 2022, the position may be communicated to an indicator 2190 that indicates the position of the firing element. The indicator may be a visual indication screen, such as feedback meter 1005, or a haptic indication.

[0150] The devices disclosed herein can be designed to be disposed of after a single use, or they can be designed to be used multiple times. In either case, however, the device can be reconditioned for reuse after at least one use. Reconditioning can include any combination of the steps of disassembly of the device, followed by cleaning or replacement of particular pieces, and subsequent reassembly. In particular, the device can be disassembled, and any number of the particular pieces or parts of the device can be selectively replaced or removed in any combination. Upon cleaning and/or replacement of particular parts, the device can be reassembled for subsequent use either at a reconditioning facility, or by a surgical team immediately prior to a surgical procedure. Those skilled in the art will appreciate that reconditioning of a device can utilize a variety of techniques for disassembly, cleaning/replacement, and reassembly. Use of such techniques, and the resulting reconditioned device, are all within the scope of the present application.

[0151] As previously stated, the unique and novel aspects of the various embodiments of the present disclosure utilize an electronic sensor to determine the position of a firing element in the end effector of a surgical instrument and/or the status or presence of a staple cartridge in the end effector. Thus, the unique arrangements and principles of various embodiments of the present disclosure may enable a variety of different forms of the electronic sensor disclosed and claimed herein to be effectively employed in connection with other types and forms of surgical instruments, end effectors and staple cartridges used in conjunction with a firing element. The foregoing discussion describes a robotic system with a surgical cutting and fastening instrument according to some embodiments of the present disclosure. However, as previously stated, those of ordinary skill in the art will appreciate that a surgical instrument according to various embodiments of the present disclosure may be powered and controlled in an alternative manner.

[0152] The foregoing description and following claims are intended to cover all modification and variations that are within the scope of the present disclosure. Although dimensions are illustrated in some of the figures, those dimensions are meant as example embodiments and are not to be construed as limiting. Where materials are disclosed for certain components, other materials may be used.

[0153] Any patent, publication, or other disclosure material, in whole or in part, that is said to be incorporated by reference herein is incorporated herein only to the extent that the incorporated materials does not conflict with existing definitions, statements, or other disclosure material set forth in this disclosure. As such, and to the extent necessary, the disclosure as explicitly set forth herein supersedes any conflicting material incorporated herein by reference. Any material, or portion thereof, that is said to be incorporated by reference herein, but which conflicts with existing definitions, statements, or other disclosure material set forth herein will only be incorporated to the extent that no conflict arises between that incorporated material and the existing disclosure material.