Cylinder Type Lock and Key

The present invention relates in general to cylindrical type locks and keys and more particular to the so called plug type cylinder lock wherein a generally round key shank is inserted into a cylindrical bore of a plurality of tumbler wheels rotatably mounted within the cylindrical lock.

Various types of cylindrical type locks have been made heretofore wherein a manually operable dial member or key is manipulated to rotate the tumbler members within the lock to align tumbler wheel gates with a fence member in order to allow opening of the lock. Most of these prior locks have been complicated to manufacture, require many separate lock parts which require intricate assembly operations and in general have not been as entirely satisfactory as I perceive a cylindrical type lock should be in order to operate effectively while being relatively simple to assemble and inexpensive to produce.

It is therefore the primary object of the present invention to disclose and provide a cylinder type lock and key wherein a plurality of tumbler wheels may be formed and assembled in a simple manner to provide an effectively operating lock which will provide the pick proof characteristics and manufacturing simplicity required to product a widely acceptable and inexpensively manufactured lock and key product. It is a further object to provide such a lock and key arrangement wherein the lock parts may be provided in subassemblies which are simply stacked together and then simply and securely fitted in operable position within the associated lock body.

Generally stated, the present invention in a cylindrical type lock having a rotatable cylinder within a lock body, the cylinder having a plurality of gated tumbler wheels rotatable therein and a fence member interpose between the cylinder and body to prevent relative rotation of the cylinder and body unless the tumbler wheels are properly aligned by an associated key to allow reception of the fence member into the tumbler wheel gates, contemplates the provision of a stacked array of a plurality of nested tumbler wheels and spacer discs in an alternating repetition of wheels and discs and specifically wherein the wheels and discs are each provided with identically configured annular projections on one side and annular recesses on an opposite side such that the projections of the wheels and discs are received in the adjacent recess of the adjacent wheel or disc so that the wheels and discs have an interfitting nested relationship.

More specifically, the present invention contemplates the provision of a stacked array of nested tumbler wheels and spacer discs as described wherein the wheels and discs may be simply stacked in alternating fashion into a stack thereof which is then slip fit into a cylinder, the spacer disc having projecting stop tabs which slip into an annular groove in the cylinder to thereby hold the spacer disc stationary while the nested tumbler wheels are free to be rotated through engagement between an inserted key and radially inwardly extending projections on the tumbler wheels. An end disc is axially movable in the cylinder and biased toward the array to maintain a nested array of tumbler wheels and spacer discs, which are otherwise loosely stacked in assembled operative relation interfitted with one another. The subassembly of tumbler wheels, spacer discs, the end biased assembly disc and cylinder are then simply assemblable as a unit into the lock body and held therein by an appropriate snap ring fitted into a snap ring receiving groove internally of the lock body.

A key member of generally cylindrical shank configuration is provided with a series of spaced alternating coded and blank webs with a top guide groove to facilitate initial alignment of the key shank within the lock body. The blank webs merely ride within fully open bores within the spacer discs while the coded webs selective abut radially inwardly extending projections provided on the tumbler wheels. The coded webs are selectively formed to cause predetermined extent of rotation for an aligned tumbler wheel when the key is rotated such that on alignment of the tumbler wheel gates to an associated fence member, the cylinder may be rotated within the lock body to open the associated bolt mechanism with which the lock may be employed. It is believed that a better understanding of the present invention, as well as an appreciation of additional objects and advantages thereof, will be afforded to those skilled in the art from a consideration of the following detailed description of a preferred exemplary embodiment thereof. Reference will be made to the appended drawings which will first be briefly described.

FIG. 1 is a perspective view of a preferred exemplary embodiment of cylindrical lock and key, in accordance with the present invention, the key shank being illustrated in blank or non-coded configuration;

FIG. 2 is a section view through the cylinder lock of FIG. 1 taken therein along the plane II--II;

FIG. 3 is a rear end view of the cylinder lock of FIG. 2 taken therein along the plane III--III;

FIG. 4 is a section view of the cylinder lock of FIG. 2 taken therein along the plane IV--IV;

FIG. 5 is a section view of the cylinder lock of FIG. 2 taken therein along the plane V--V;

FIG. 6 is a detail front view of the cylinder lock of FIG. 2 taken therein along the plane VI--VI;

FIG. 7 is a view as in FIG. 6 showing a portion of the key shank inserted therein;

FIG. 8 is a view as in FIG. 7 showing the key shank fully rotated in a clockwise direction;

FIG. 9 is an exploded perspective view of the exemplary embodiment of cylindrical type lock and key of the present invention and of FIGS. 1 through 8;

FIG. 10 is a side view of the blank key shank of FIG. 1 shown inserted into the cylindrical type lock of the present invention illustrated in dotted line;

FIG. 11 is an end view of the shank of FIG. 10 taken therein along the plane XI--XI;

FIG. 12 is a section view through the key shank of FIG. 10 taken therein along the plane XII--XII;

FIG. 13 is a section view of the key shank of FIG. 10 taken therein along the plane XIII--XIII;

FIG. 14 is a schematic representation of the coding of the key shank tumbler wheels of the shank of FIG. 10;

FIG. 15 is a detail view of the lock portions of FIG. 4 showing the fence pin in an alternate position; and

FIG. 16 is a detail view of the lock portions of FIG. 5 showing the fence pin in the alternate position.

Referring initially to FIG. 1, a preferred exemplary embodiment of cylindrical type lock and key, in accordance with the present invention, will be now explained in detail. The exemplary key blank is indicated generally at 10 in FIG. 1 and has a shank 12 which is provided with a shank bore 12a. As seen at the right hand end of shank 12, a suitable handle or hilt 11 may be provided on the left hand end of shank 12, is seen in FIG. 1, a plurality of blank annular disc like webs, indicated generally at 14, are provided with a longitudinally extending guide slot, indicated generally at 17, extending along upper portions thereof to guide the shank entry to the lock body as will be explained more fully hereinafter.

The exemplary cylindrical type lock, in accordance with the present invention, is indicated generally at 20 in FIG. 1 and includes a body 21 of generally cylindrical configuration having external threads 22 for mounting the lock in a safe door, or the like; with the lock nose or face 23 protruding forwardly of the safe door. The lock body has a bore 24 which receives a rotatable cylinder 25, the latter being best seen in FIGS. 2 and 9. Cylinder 25 has a key shank guide post 25a. A threaded stud 26 is provided on a rear portion of cylinder 25 to cooperate with a latch actuating member associated with the safe to which the lock is assembled. As best seen in FIG. 2, a snap ring 27 is provided to fit within an interior annular snap ring receiving groove 28 provided in body 21 to hold the cylinder within the body. A drive lug 29 is formed interiorly of the cylinder to cooperate with an end driver web 15, as seen in FIGS. 10 through 12, on the key shank 12.

Rotation between cylinder 25 and lock body 21 is normally prevented by virtue of the provision of a fence member 30 which comprises a pin like configuration in the exemplary embodiment. Cylinder 25 is provided with an longitudinal slot 31, as best seen in FIGS. 2, 3 and 9, receiving fence member 30 for movement therein, member 30 being normally biased outwardly by the two fence springs 34. Channel 31 has spring slots 31a and 31b while fence member 30 has spring grooves 33a and 33b. As best seen in FIGS. 4 and 15, springs 34 cooperate with fence member 30 in biasing in outwardly of the cylinder to act in conjunction with the tumbler wheels as discussed hereinafter. Cylinder 25 further is provided with a top longitudinal slot 35, as seen in FIG. 9, for receiving portions of the specer discs on there assembly to the cylinder 25 as discussed hereinafter.

As in particularly contemplated within the present invention, a stacked array of a plurality of nested and alternating tumbler wheels and spacer discs are provided in a preassembly with the cylinder 25 which is easily assembled to the lock body 21. The spacer wheels 40 are best seen in FIGS. 2 and 9 include, in the exemplary embodiment, four separate spacer wheels or discs 40a, 40b, 40c, and 40d. Each of the spacer discs 40 include an annular body such as 41a in FIG. 4, a stop tab projecting radially outwardly of an upper portion thereof such as tab 42a in FIG. 4, a fence receiving notch such as notch 43a in FIG. 4, a front annular boss or projection such as projection 44a in FIG. 2, a rear annular recess such as recess 45a as seen in FIG. 9 and a central bore such as bore 46a in FIG. 9. Two of the spacer discs, 40a and 40d, are provided with spring receiving slots 47a and 47d, respectively as best seen in FIG. 2. When the spacer discs and tumbler wheels 50 are placed in stacked and nested relation, and assembled to cylinder 25, the spacer disc stop tabs 42a-42d slip fit into longitudinal groove 35 in order to be held stationary within cylinder 25 during operation of the lock as discussed hereinafter.

A plurality of tumbler wheels 50 are provided in the stacked array of wheels and discs as seen in FIG. 2. In the exemplary embodiment, and as seen in FIGS. 2 and 9, five tumbler wheels 50a through 50e are provided with each of the wheels 50 having an annular body such as body 51a in FIG. 5, a plurality of false gates 52a through 52k as seen in FIG. 5, a single true gate such as gate 53 in FIG. 5, a front annular boss or projection identical to the projection on the spacer dics, such as projection 54d in FIG. 2, a rear annular recess identical to the rear recess on each of the spacer discs, such as rear recess 55d as seen in FIG. 9, a central annual bore such as bore 56d in FIG. 9 and a tumbler wheel drive tab as tab 57d in FIG. 5, which cooperate with the coded webs of the key shank as discussed hereinafter. While the spacing of the false gates in the exemplary embodiment is 30.degree., such spacing could be less, such as 20.degree..

The array of tumbler wheels 50 and spacer discs 40, as seen in FIG. 9, are simply stacked one on the other in nested relation with the identical projections of each disc and wheel fitting into the mating and identically configured recesses of adjacent wheels or discs, as seen in FIG. 2, and with the assembly of springs 34 into the spacer disc slots 47a and 47d, and with the fence member 30 received in aligned tumbler wheel gates, the thus formed subassembly is merely slipped in to the cylinder 25. An assembly spacer wheel 60 is then inserted loosely within a wider internal annular notch 61 formed on an outer end of the cylinder and with bias spring 62 placed on the spacer wheel 60, the cylinder assembly in simply inserted into the lock body 21 and held therein by snapping snap ring 27 into the body groove 28. A simply assembled and effectively operating cylindrical type lock is thus provided. The spacer wheel 60 has a rounded periphery 63 to more easily slide in groove 61 under the bias of spring 62 which urges the stacked array of spacer discs and tumbler wheels into their desired nested, interfitting relationship as seen in FIG. 2. Wheel 60 has a central bore 64 to facilitate passage of the lock operating key which will now be discussed.

As is also contemplated within the present invention in cylindrical lock and key, the exemplary embodiment of key is provided with a plurality of alternating coded webs 13 and blank webs 14. As best seen in FIG. 10, the exemplary key shank is provided with five coded webs 13a through 13e. The cross section configurations available for each of the coded webs 13, in accordance with the best invention, are illustrated somewhat schematically in FIG. 14 where various selectable sizes for the solid web section for each web are illustrated by the construction lines labeled by the number of degrees from vertical that a cutting tool would cut portions of the web away from the shank. The 18 degree construction line by way of example illustrates a web which extended all the way around the shank but for a cut-out segment of 18 degrees on either side of the vertical on the top of the shank as seen in FIG. 14. Continuous overlapping radial cuts can be made to produce a cut-out of any of the number of degrees indicated on the succeeding construction lines in FIG. 14, it being contemplated in this example that the cut-outs would vary between 18 degrees and 213 degrees as shown in FIG. 14. Other angles of cut and number of degrees per increment between cuts can be selected to produce different codes. The surface of the web facing the notch made by the selected web cut engages the inward projection, as projection 57d in FIG. 5, of an aligned tumbler wheel when the key shank is fully inserted as seen in FIG. 10 and rotated to manipulate the lock tumblers.

The blank webs 14a through 14g are full angular webs but for the guide notch 17 which runs longitudinally along the upper portions of the shank through both the blank webs 14 and coded webs 13. As best seen in FIGS. 10, 11 and 12, and forward end of shank 12 is provided with a drive web 15 which is adapted to engage the key abutment 29 within cylinder 25 when the key has been rotated sufficient to cause the coded webs to move the tumbler wheels into proper alignment to place their respective gates in positions opening to and receiving the fence member 30. The extent of key rotation may be limited by a stop web 16 near the inner end of the web, web 16 may be configured to have a fairly small solid web section, as seen in the section view of FIG. 13 to limit turning movement of the key within the lock body.

When the key shank is inserted into the central bore of the lock body, the cylinder guide post 25a will be received within the shank bore 12a to guide the shank centrally of the nested array of tumbler wheels 50 and spacer wheels 40. When the key shank is fully inserted, as seen in FIG. 10, the coded webs 13 are aligned to the tumbler wheels 50. By predetermining the location of the tumbler wheel true gates 53 relative to where the wheels will be turned through abutment between the coded webs and the wheel projections 57, the lock can be coded for a particular key to align the tumbler wheel true gates when the inserted key is turned sufficiently clockwise to bring the drive web 15 into engagement with the cylinder key abutment 29 to commence rotation of the cylinder within the lock body. On such relative rotation, fence member 30 will roll up ramp 24a provided on the cylinder and move into the aligned true gates of the tumbler wheels and gate notches 43 of the spacer discs. If the tumbler wheels are not properly aligned, the fence member 30 will wedge between the cylinder and lock body at ramp 24a preventing opening of the lock. Assuming that the tumbler wheels are properly aligned by having inserted and rotated the proper key, the cylinder will continue to rotate on turning of the key until the key is fully rotated to bring the stop web 16 into abutment with the lock body abutment 23a as best seen in FIG. 8. By this time, an associated latch is rotated sufficiently to unlock the associated safe door through connection between cylinder stud 26 and such associated lock actuator.

Having thus described a preferred exemplary embodiment of a cylinder type lock and key in accordance with the present invention, it should be understood by those skilled in the art that various additional advantages and objects of the present invention have been attained, that various modifications, adaptations and alternative embodiments may be made thereon, the present invention being defined by the following claims.