Method and Apparatus for Economizing Fuel Consumption in Operating a Multicylinder Internal Combustion Engine

This invention relates generally to internal combustion engines, and particularly to multicylinder type internal combustion engines used in powering automobiles.

Varying power demands placed on automobile engines presents a technical dilemma. Where the engine is sufficiently powerful to handle high power demand conditions, it inherently has an excess of power availability during periods of relatively low power demand. Conversely, where the engine is constructed to meet only low power demand conditions efficiently, it fails to handle high power demands satisfactorily.

Previous attempts have been made to overcome the just described dilemma by periodically changing the number of operating cylinders as engine load conditions vary. U.S. Pat. Nos. 2,250,814, 2,394,738 and 2,652,038, for example, accomplish this by closing all valves to selected cylinders during low power demand conditions to render them temporarily inoperative. U.S. Pat. No. 2,673,617, for another example, accomplishes this through the use of multiple throttle valves. Though these approaches were feasible as modifications to automobile engines of the 1930's and 1940's, they are impractical and inefficient to incorporate into the automobile engines of today.

U.S. Pat. Nos. 2,085,818 and 2,114,655 disclose systems in which air is selectively admitted through intake manifolds to certain cylinders of an engine, so as to interrupt the draw of fuel and air from the carburator, such action being controlled by the voltage of the generator and the position of the throttle in U.S. Pat. No. 2,085,818 and by the vacuum in the manifold in U.S. Pat. No. 2,114,655. U.S. Pat. No. 1,121,114 discloses an engine in which the drive shaft to a portion of the engine is coupled and uncoupled, the intake valves of the uncoupled cylinders being opened during the period in which an uncoupled condition exists. The Applicant is also aware of the following additional U.S. Pat. Nos. 1,910,350; 3,578,116; 2,623,617 and 3,757,651.

Accordingly, it is a general object of the present invention to provide improved methods and apparatuses for economizing fuel consumption in operating internal combustion engines.

More specifically, it is an object of the present invention to provide an improved method of reducing the number of operating cylinders in a multicylinder internal combustion engine under low power demand conditions.

Another object of the invention is to provide an internal combustion engine having a plurality of combustion chambers with improved means for altering the number of combustion chambers in operation at any one time.

Another object of the invention is to provide means for converting existing internal combustion engines of automobiles to that of the type above described without need for modification of those portions of the engine housed within the engine block.

Yet another object of the invention is to provide an economical manner for altering existing multicylinder internal combustion engines to incorporate means for placing selected member combustion chambers in an inoperative condition while retaining operativeness of the unselected member combustion chambers.

In one form of the invention, a method is provided for economizing fuel consumption in operating an internal combustion engine having a group of combustion chambers of preselected number. The method comprises the steps of consecutively introducing combustible fuel for ignition into each combustion chamber of the group to provide relatively high power availability for period of relatively high power demand, and of consecutively introducing combustion chambers of the group while venting the unselected members of the group to ambient atmosphere to provide relatively low power availability for period of relatively low power demand.

In another form of the invention an internal combustion engine is provided comprising a group of combustion chambers and means for continuously venting selected member chambers of the group during periods of relatively low power demand to render them temporarily inoperative and thereby economize fuel.

In yet another form of the invention an internal combustion engine is provided comprising a plurality of cylinders, a plurality of valves operatively associated with said cylinders, means for continuously cycling each of the valves between valve opened and closed positions, and means for terminating the cycling by holding open selected valve members of the plurality of valves while the unselected valve members continue the cycle.

FIG. 1 is a transverse sectional view of an internal combustion engine embodying principles of the invention in a preferred form that is capable of practicing methods of the invention.

FIG. 2 is a plane view, partially schematic, of a portion of the internal combustion engine shown in FIG. 1.

FIG. 3 is a schematic view of a combined electrical and hydraulic control means associated with the internal combustion engine shown in FIGS. 1 and 2.

FIGS. 4 and 5 illustrate, partially in cross-section, modified portions of the internal combustion engine shown in FIG. 1 embodying principles of the invention in another form undergoing a sequence of operations.

FIG. 4a is a view similar to FIG. 4 and showing another modified form of the invention in which an electrical solenoid is used.

FIG. 6 is a plan-view, partially in schematic form, of a portion of an internal combustion engine incorporating the modification shown in FIGS. 4 and 5.

FIG. 7 is a schematic view of a combined electrical and hydraulic control means for operating the internal combustion engine components shown in FIGS. 8 and 9.

FIG. 8 is a fragmentary view of yet another modification to the internal combustion engine shown in FIG. 1.

FIG. 9 is a plan-view, partially schematic, of an internal combustion engine incorporating the control means shown in FIG. 7 and the modifications shown in FIG. 8.

FIG. 10 illustrates, partially in cross-section, another modification of the internal combustion engine shown in FIG. 1.

FIG. 11 is a schematic diagram of a fuel control system for diesel and gasoline fuel injection engines embodying the invention.

Referring now in more detail to the drawing, there is illustrated in FIG. 1 a conventional V-8 internal combustion engine for an automobile having the head thereof modified to incorporate principles of the invention. That portion of the engine illustrated here is seen to include two pistons 10 mounted for reciprocal, linear motion within cylinders 12 formed within engine block 14. A piston rod 16 extends from each piston 10 out the lower end of the cylinder to a crank 18 rigidly mounted to a crank shaft 20. The spaces within the cylinders above the pistons provide combustion chambers 22.

With reference next to both FIGS. 1 and 2 the engine is further seen to comprise a four barrel carburetor 25 mounted atop a carburetor mounting plate 26 which defines four barrels that respectively communicate with fuel intake manifolds 27, 27', 28 and 28'. Each of the four fuel intake manifolds communicates in turn with two cylinders within block 14. Momentary communication between the cylinder combustion chambers and the intake manifolds is controlled by means of fuel intake valves 30. Each fuel intake valve is continuously biased by means of a compression spring 32 into a closed position upon a conical seat 35. A conventional rocker arm 37 is provided for moving each of the fuel intake valves in conventional fashion. The rocker arms are mounted for rotation upon rocker arm shafts 38. One end of each rocker arm abuts an end of a valve stem 40 which extends from valve 30 through compression spring 32. The other end of each rocker arm is connected with a split rod type tappet or valve lifter movably housed within block 14. Each lifter comprises an upper rod 41 having its upper end pivotably secured to the rocker arm and its lower end telescopically received within the hollow upper end of a lower rod 42. A compression spring 43 is positioned about rod 41 with one end thereof in abutment with rod 43 and the other end in abutment with a stop 44 secured to rod 41. An enlarged lower end of each lifter abuts a cam 45 rigidly mounted to a rotatable cam shaft 46. With this configuration rotation of the cam shaft is seen to cause valve lifters 42 to reciprocate, causing the fuel intake valves to open and close consecutively in conventional Otto cycle fashion. Other conventional structural elements of the engine are seen to be an exhaust manifold 50, chassis motor mounts 52, head cover 54 and chassis 55.

With continued reference to FIGS. 1 and 2, means are seen to be provided for terminating the cycling of the fuel intake valves of four cylinders during period of relatively low power demand. This mechanism includes two pairs of push rods 56 that extend out the opposite ends of a pair of double acting cylinders 57. Each rod is seen to carry a conical rocker arm stop 60 which is loosely disposed about the rod between a pair of compression springs 61. The end of each compression spring distal the conical rocker arm stop is held stationary to the rod by means either of the double acting cylinders 57 themselves or a collar 63 rigidly secured to the rod. With this configuration it will be seen that actuation of the double acting cylinders serves to position the rocker arm stops 60 in abutment atop the rocker arms 37 thereby holding them in positions depressing valves 30 thereby holding them open.

While the fuel intake valves are depressed, rotation of cam 45 becomes ineffectual in imparting motion to the valve lifter upper rods 41. Instead, the lower rods merely ride up and down upon cam 45 alternately compressing and decompressing springs 43. This insures that the tappet maintains its position within block 14 continuously atop the rotating cam 45. Simultaneous with this action butterfly solenoid valves 66 are actuated as hereinafter described, venting intake manifolds 27 and 27' which communicate with the combustion chambers through opened valves 30. In this manner the combustion chambers 22 are themselves vented to ambient atmosphere which inhibits their drawing combustible fluids from carburetor 25 as pistons 10 reciprocate in cylinders 12. Thus, four of the eight cylinders cease to be operative in imparting driving force to the power train. At the same time, drag which would be created by the evacuation of the combustion chamber does not arise which leaves the inoperative cylinder free to reciprocate. It should be specifically noted that no modification has been made to the engine block or engine components housed therein. Instead, they have been simply and economically made to the head and components operating therein. If desired, vent means could be built directly into the cylinder combustion chambers independent of the valves housed within the engine head.

With reference next to FIG. 3, a control system is shown for operating double acting cylinders 57. The control system is seen to include a switch 70 having a terminal 71 connected to ground through a battery 72 and two other alternately selectable terminals 73a and 75 coupled with serially connected coils 73 and 74 to ground.

Terminal 75 leads to the normally closed series connected interlock switches 75a, 77, 79 80 and 81a. Switch 75a is connected to a thermocouple 75b which opens and closes the switch 75a. Switch 75a remains open until the engine reaches normal operating temperature and is then closed. Switch 77 is normally closed but is opened by the throttle foot pedal 76 when depressed beyond a preselected limit of the carburetor throttle valve opening where all cylinders are needed for the power required. For example, the switch 77 is connected to the linkage 76a of the carburetor bufferfly valve so as to open when the butterfly valve is opened more than 45.degree..

Switch 79 is opened when the gear lever 78 is shifted away from third or neutral gear. Switch 81a is operated by the transmission mechanism 81b and is opened when transmission is in, the intermediate gears.

When switch 70 connects terminals 71 and 73a these switches 77, 79, 80 and 81a are bypassed or shunted via wire 81c so as to energize coils 73 and 74, regardless of the positions of switches 77, 79, 80 and 81a.

When however, switch 70 is positioned to connect terminal 75 with terminal 71 and battery 72, a circuit is established energizing coils 73 and 74 only so long as the engine is within its normal operating temperatures or automobile accelerator pedal 76 is not in a position beyond about 45.degree. to open switch 77, or a low gear shift lever 78 is not positioned to actuate a switch 79, or an engine torque switch 80 is not actuated by high torque or the switch 81a is not actuated by the hydraulic transmission being in less than its normal drive.

With coils 73 and 74 energized, valve 82 serves to actuate the double acting cylinders 57 in urging the rocker arm stops into position for low power operation. This is accomplished by means of an hydraulic line 85 which communicates by means of T couplings 86 to branch lines 88 and cylinders 57. In this mode of operation should more power be demanded as by maximum depression of accelerator 76, transmission to low gear, or in high engine torquing switch 77, 79 or 80, or a combination thereof, open thereby de-energizing valves 82. This causes the double acting cylinders to disengage rocker arm stop 60. Simultaneous with the de-activation of valves 82, butterfly solenoid valves 66 are de-energized which terminates the venting of intake manifold 27 and 27' to ambient atmosphere. In urging stops 60 against the rocker arms, springs 51 cushion impact.

With reference next to FIGS. 4, 4a, 5 and 6, means for maintaining valves 30 in a valve open position are shown in alternative forms. Here, rocker arms 37 may be held depressed by cams or levers 90 pivotally mounted to rods 91. These cams or levers 90 have a limited degree of rotary movement relative the rods 91 under the bias provided by springs 92. Relative movement by the cams 90 with respect to the rods against a spring 92 provides shock absorbing means as the cams engage the rocker arms 37. Rods 91 themselves are rotated by means of a crank arm 95a mounted to a fixed collar 96a. Upon actuation of a hydraulic cylinder 96, cams 90 engage and hold the rocker arms 37 in the position shown in FIG. 5, thereby holding valve stems 40 depressed against the action of springs 32 to hold the fuel intake valves open. Deactivation of cylinders 96 returns the cams 90 to the position shown in FIG. 4, thereby releasing the rocker arms 37, enabling them to assume their normal Otto cycling motion. Cylinders 96 are actuated in a similar manner to that previously described in FIG. 3 in conjunction with double acting cylinders 57. It will be understood, of course, that solenoids, such as solenoid 196, seen in FIG. 4a, can be substituted for the cylinder 96, if desired, without departing from the scope of this invention. Solenoid 196 is disposed in place of all the hydraulic systems including solenoids 73 and 74. The energizing of solenoid 196 will extend rod 195. Rod 195 acts in the identical manner as rod 95 in rotating cam 90 to hold open the intake valve, once the rocker arm 37 has opened the valve. The retracting of rod 195 when solenoid 196 is de-energized causes release of rocker arm 37.

Referring next to FIGS. 7, 8 and 9, yet another embodiment is illustrated similar to that shown in FIGS. 1 and 2. Here, however, pairs of rocker arm stops 60 are mounted to single, unitary rods 99 and 99' rather than to pairs of individual rods. In this manner actuation of each pair occurs by movement of one rod in one direction. Specifically, the rods are driven by rigid coupling members 100 mounted to the rods with one end passing through a flexible gasket 101 covering an aperture in head cover 54 to a piston rod 102. The piston rods are in turn mounted to pistons housed within cylinders 104 to which pairs of hydraulic lines 105 communicate. Lines 105 are connected through a shuttle valve 106, actuatable by means of a solenoid 108.

As shown previously in FIG. 4A, cylinder 104 of FIG. 8 can be replaced by an electrically operated solenoid 106 replacing all the hydraulic circuit.

If desired, means may be provided for actually terminating the flow of fuel to the carburetor in communication with inoperative combustion chambers. Such a modification is shown in FIG. 10 wherein two, two-barrel carburetors 25' are shown independently mounted atop an adapter 87 which itself is mounted atop the carburetor mounting place. A solenoid actuatable valve 89 is mounted in the fuel line that communicates with that carburetor operatively associated with the cylinders adapted to be temporarily rendered inoperative. The solenoid is preferably connected in parallel circuit with butterfly solenoid valves 66 for simultaneous operation therewith. Where fuel injectors are used in lieu of carburetors, such as with diesel and gasoline injected internal combustion engines, shut off valves may also be used. FIG. 11 exemplifies one such arrangement for a V-8 engine 120 having eight intake fuel lines 124 leading to eight fuel injectors 122. Four solenoid actuated valves 126 are incorporated into the lines 124 leading to the injectors 122. When valves 126 are actuated they interrupt the flow of fuel to their respective injectors 122 and directs all such fuel, via lines 125, back to the fuel tank.

While I have illustrated, in the present invention, employing cams 60 and 90 to hold open the intake valves 40, a similar result could be obtained by using eccentric bushings on the rocker arms to lift the rocker arms to hold the valves closed rather than opened; however, the engine in such a situation runs in a rough manner and, therefore, such a procedure is not recommended.

The fuel economy, using my invention is quite noticeable. For example, in an automobile which normally travelled about 91/2 miles per gallon, my invention increased this about 121/2 miles per gallon.

It should be understood that the just described embodiments merely illustrate principles of the invention in selected, preferred forms. Many modifications, additions and deletions may, of course, be made thereto without departing from the spirit and scope of the invention as set forth in the following claims.