US3311101A - Excess fuel starting device for fuel injection engines - Google Patents

Description

March 28, 1967 A. E. HUSE 3,311,101

EXCESS FUEL STARTING DEVICE FOR FUEL INJECTION ENGINES Filed Nov. 10, 1964 a Sheets-Sheet 1 INVENTOR: ARTHUR E. HUSE ATTY5.

A. E. HUSE March 28, 1967 EXCESS FUEL STARTING DEVICE FOR FUEL INJECTION ENGINES 2 Sheets-Sheet 2 Filed Nov. 10, 1964 FIGZ.

United States Patent poration of New York Filed Nov. 10, 1964, Ser. No. 416,183 4 Claims. (Cl. 123-479) The present invention relates to a hydraulically actuated starting device for fuel injection engines which automatically permits an excess fuel delivery during cranking of the engine.

To facilitate the starting of a fuel injection engine, it is desirable during cranking to provide a fuel delivery in excess of the normal full load delivery. Since the fuel delivery is generally limited by a full load stop coacting with the engine throttle linkage, it is necessary, in order to permit an excess fuel injection, to provide a mechanism which changes the position of the full load stop during the engine cranking period. Although manually set mechanical tripping devices have heretofore been utilized for such purpose, the present invention provides a fully automatic excess fuel control which is hydraulically actuated by an engine-pressurized fluid such as the engine lubricating oil.

In view of the above, it is a primary object of the present invention to provide a fully automatic fuel injection engine starting device permitting fuel delivery in excess of the normal full load delivery during cranking to facilitate engine starting.

A further object of the invention is to provide a device as described which permits such an excess fuel delivery for a sufficient time during the engine starting period to assure adequate fuel delivery while the engine is cold and to prevent stalling of the engine in the event of a momentary misfire.

Another object of the invention is to provide a device as described which automatically reduces the permissible maximum fuel delivery to the normal full load fuel limit after the engine starts to prevent overfueling.

A still further object of the invention is to provide a device as described which upon engine stoppage is automatically reset to permit the desired excess fuel condition.

Additional objects and advantages of the invention will be more readily apparent from the following detailed description of an embodiment thereof when taken together with the accompanying drawings in which:

FIG. 1 is a side elevational view partly in section of a fuel injection pump assembly incorporating an excess fuel device in accordance with the present invention;

FIG. 2 is a view taken along line 22 of FIG. 1 showing the excess fuel device in an end elevational view;

FIG. 3 is a side elevational sectional view of the device taken along line 3-3 of FIG. 2, showing the device in the excess fuel starting position;

FIG. 4 is a view as in FIG. 3 showing the device shortly after starting of the engine;

FIG. 5 is a view as in FIGS. 3 and 4 showing the device in the normal full load operating position;

FIG. 6 is a sectional view taken along line 66 of FIG. 3; and

FIG. 7 is a sectional view taken along line 77 of FIG. 3.

Referring to the drawings FIG. 1 shows the present starting device as applied to a well known type of fuel injection pump and governor. The apparatus includes a fuel injection pump 10 enclosed within housing 12 and an adjoining governor 14 within housing 16. The pump 10 includes hydraulic head 18 having a central Vertical bore 20 within which pumping and distributing plunger 22 is slidably and rotatably disposed.

3,311,101 Patented Mar. 28,1967

The pump is driven from the fuel injection engine by means of the gear 23 on the cam shaft 24 which is journaled in the housing 12 by the bearings 26 and 28. The cam shaft includes cam 30 having cam lobes 32 coacting with the roller 34 of the tappet 36 to effect a reciprocating vertical stroke of the pumping and distributing plunger 22 in conjunction with the return spring 38.

A drive gear 40 mounted on the cam shaft 24 is engaged with gear 42 on the governor shaft 44 to continuously drive the governor shaft in rotation. Mounted on the governor shaft are centrifugal weights 46, the centrifugal action of which through a spring loaded linkage 47 governs the position of the fulcrum lever 48 by means of the pin and slot connection 49. Pivotally connected with the upper end of the fulcrum lever 48 is the fuel control rod 50, the movement of which controls the fuel output of the fuel injection pump as described further below. The lower end of the fulcrum lever is operatively secured by pin connection 51 to trunnion lever 52 on the operating lever shaft 53.

The driven gear 42 on the governor shaft 44 in turn drives the face gear 54 which drives the pumping and distributing plunger 22 in rotation. The plunger 22 is thus continuously rotated at a rate corresponding with the speed of the engine.

The hydraulic head 18 includes a peripheral fuel sump 55 into which opens the fuel inlet passage 56 and inlet port 58. The inlet port 58 connects with the annular slot 60 in the bore 20, thus providing a fuel passage from the sump 55 through which fuel is delivered under pressure by a fuel supply pump (not shown) into the plunger bore. The fuel, on reaching the bore 20 is forced by the upward movement of the plunger 22 through the check valve 62 of the delivery valve assembly 64. The fuel flows through the delivery valve assembly through the passages 66 and 68 and into the annulus 70 of the plunger 22 which connects with the distributor port 72. The rotation of the plunger 22 is timed to position the distributor port 72 in alignment with an outlet passage 74 leading into an outlet 76 for delivery of fuel to a cylinder nozlzle in the proper phase relationship to the engine cyc e.

The amount of fuel delivered by the pump is controlled by the sleeve 78 which is vertically positioned along the plunger 22 within the spill sump 80 by the fuel control rod 50 (connection shown in broken lines). An axial hole 82 in the plunger extends from the upper end thereof to the transverse spill hole 84 which serves to release the fluid pressure on the check valve 62 to close the valve when the spill hole clears the upper edge of the sleeve 78. It can thus be understood that a higher sleeve position will delay the opening of the spill hole and thus by increasing the period during which the check valve is open providing an increased delivery of fuel to the cylinder. Conversely, a lowered sleeve position will result in a decreased fuel delivery.

The advancement of the engine throttle linkage, and specifically the fuel control rod 56 is limited in the direction increasing the fuel delivery (to the right in FIG. '1) by the full load stop 86 characterized by a vertical plate positioned so as to limit the movement of the upper end of the fulcrum lever 48 by contact with either the adjustable stop screw 88 or cam 90 thereof. The full load stop 86 in the usual installation would be secured to the governor housing in a fixed or manually adjustable manner. The present invention provides an arrangement whereby the full load stop is automatically repositioned to permit an excess fuel delivery during cranking of the engine.

The full load stop plate is threadedly connected to the piston rod 92 of a cylinder-piston actuator 94, mounting arms 96 of which are secured to the governor housing 16 by means of screws 98 as shown in FIG. 2. Lock nut 99 is provided on the threaded piston rod to prevent rotation of the rod. The proper alignment of the stop plate is maintained by means of a guide pin 100 parallel with the piston rod 92 which slidably coacts with a bore 101 in the actuator housing 102.

The actuator includes a hollow piston 104 slidably fitted within the cylindrical bore 106. The piston rod 92 terminates inwardly in a cylindrical piston rod head 108 the end' of which is secured to the hollow piston 104. A cylindrical compression spring 110 concentrically positioned over the piston rod by the piston rod head 108 urges the piston inwardly. The outer end of the spring is seated upon stop disc 114 which is concentrically bored to receive the piston rod. The stop disc is secured against shoulder 118' of the actuator housing by the retaining ring 120 seated within a slot in the housing.

A fluid conduit 122 which is connected with a source of engine pressurized fluid such as the engine lubricating oil or fuel supply, leads into a fluid inlet 124 in the actuator housing which opens into the inner end of the actuator bore 106. The piston 104 includes a peripheral slot 126 which, as shown in FIG. 3, permits a fluid flow from the inlet circumferentially about the end of the piston and into the concave region 128 of the housing to permit a full fluid force against the piston when the piston is in the excess fuel position.

Connected with the inlet 124 as shown in FIG. 6 is an axial fluid slot 130 extending along the inner surface of the actuator bore 106 and extending beyond the piston when the actuator is in the excess fuel position to permit the introduction of pressurized fluid to both sides of the piston. The purpose of introducing fluid to the left side of the piston is to inhibit movement of the actuator until the engine-pressurized fluid has reached a substantial pressure. Due to the presence of the piston rod to the left of the piston, the net fluid force on the piston will urge the piston to the left, and the compression spring 110 should exert a force on the piston somewhat less than the net fluid force provided by the pressurized fluid on both sides of the piston such that the piston will move slowly to the left upon starting of the engine. When the outer end 132 of the piston reaches the outer end 134 of the slot 130, as hasoccurred in FIG. 4, the pressurized fluid is cut off from the left side of the piston and simultaneously the outer edge 1360f an axial venting slot 138 in the piston rod clears the stop disc 114 thereby venting the left side of the piston to the atmosphere and permitting the full force of the pressurized fluid to move the actuator to the left to the full load position shown in FIG. 5.

' In operation, prior to the starting of the engine, the actuator is in the excess fuel position shown in FIG. 3 by virtue of the spring force urging the piston to the right and the lack of fluid pressure in the bore 106. In addition, the manual opening of the throttle by the operator will produce a substantial force through the cam 90 against the stop plate. With the full load stop in the excess fuel position, thefuel pump should deliver at least 50% more fuel during the engine cranking period than during engine operation at full load.

As the engine starts, the operator backs off on the operating lever which removes the fulcrum arm cam 90 from the stop plate. At the same time, the pressurized fluid acting on both sides of the piston slowly moves the piston against the spring force to the left. After the piston has moved a suflicient distance to cut off the flow of pressurized fluid to the left side of the piston and opened the vent slot 138 to the atmosphere, the piston moves at a rapid rate to the normal full load position shown in FIG. 5, at which position a minimum fluid pressure is sufficient during operation of the engine to prevent movement of the full load stop to the right in spite of the forces exerted by the cam 90 and the spring 110.

The slot 130 and vent slot 138 thus provide a means for inhibiting the return of the full load stop to the full load position .until suchtime as the engine has definitely started.

This arrangement prevents the return of the stop to the full load position upon the occurrence of a false start and the need on such occurrence to wait for the fluid pressure to drop off to permit the return of the stop to the excess fuel position. Although manual means could be provided to vent the fluid system upon such occurrence, the illustrated automatically operating embodiment is obviously preferable.

Upon engine stoppage, as the fluid pressure in the actuator bore drops off, the compression spring serves to return the piston and full load stop to the excess fuel position to automatically permit an excess fuel throttle setting upon restarting of the engine.

As an example of a specific operable embodiment of the invention, the fluid conduit was connected with the pressurized lubricating oil of the injection engine. A spring exerting a force of approximately one pound in the excess fuel position was employed, and it was found that the cam bearing against the full load stop plate exerted a force of approximately three to four pounds. The piston and piston rod shaft areas were such that a lubricating oil pressure of at least 50 p.s.i. was required to overcome the combined force of the spring and the fulcrum lever cam. Upon removal of the cam force on starting of the engine and the venting of the opposing fluid, the piston moved rapidly to the normal full load position and a minimum oil pressure of 10 p.s.i. was adequate to maintain the stop plate in the full load position during all conditions of engine operation. Should a false start occur before the oil pressure had reached 50' p.s.i., the cranking could be continued with the pump still delivering excess fuel. When the engine was stopped, the oil pressure dropped below 10 p.s.i. and the spring urged the piston and stop plate back to the excess fuel position ready for a further start.

Manifestly changes in details of construction can be effected by those skilled in the art without departing from the spirit and the scope of the invention as defined in and limited solely by the appended claims.

I claim:

1. An excess fuel starting device for a fuel injection engine having a full load stop coacting with the engine throttle linkage to limit the fuel input thereto comprising, a hydraulic actuator operatively connected to the full load stop for movement thereof from a normal operating full load position to an excess fuel starting position, said actuator comprising a housing on the engine having a cylindrical bore therein, a piston slidably disposed within said bore, and a piston rod extending from said bore and operatively connected with the full load stop, a spring in said bore urging said piston and full load stop into the excess fuel position, a fluid inlet in said housing opening into said bore for introducing pressurized fluid into said bore to move said piston against the force of said spring into the normal operating full load position, a fluid conduit for connecting said fluid inlet with a fluid source pressurized by and only during operation of the engine, said spring being adapted upon engine stoppage to move said piston and full load stop to the excess fuel starting position, means permitting an initial introduction of fluid to both sides of said piston during the starting of the engine to briefly inhibit movement of said piston, and means for venting fluid from one side of said piston following starting of the engine to permit a rapid movement of the actuator into the normal operating full load position and to maintain the full load position with a minimum pressure of said fluid.

2. The excess fuel starting device as claimed in claim 1 wherein said fluid source comprises the engine lubricating oil.

3. The excess fuel starting device as claimed in claim 1 wherein said fluid source comprises the engine fuel supply.

4. An excess fuel starting device for a fuel injection engine having a full load stop coacting with the engine 1 5 throttle linkage to limit the fuel input thereto comprising, a hydraulic actuator operatively connected to the full load stop 'for movement thereof from a normal operating full load position to an excess fuel starting position, said actuator comprising a housing on the engine having a cylindrical bore therein, a piston slidably disposed within said bore, and a piston rod extending from said bore and operatively connected with the full load stop, a spring in one end of said bore urging said piston and full load stop into the excess fuel position, a fluid inlet in said housing opening into the opposed end of said bore for introducing pressurized fluid into said bore to move said piston against the force of said spring into the normal operating full load position, an axial slot in said bore connecting with said fluid inlet and permit-ting a fluid flow from said inlet against both sides of said piston when said piston is in the excess fuel starting position, an axial venting slot in said piston rod for venting one end of said bore upon displacement of said piston from the excess fuel position, and a fluid conduit for connecting said fluid inlet with a fluid source pressurized by and only during operation of the engine, said spring being adapted upon engine stoppage to move said piston and full load stop to the excess fuel starting position.

References Cited by the Examiner UNITED STATES PATENTS 2,708,921 5/1955 Links 123-140 2,784,708 3/1957 Hill et al. 123139 3,153,405 10/1964 Paterson et a1. 123-139 MARK NEWMAN, Primary Examiner.

LAWRENCE M. GOODRIDGE, Examiner.

Claims (1)

1. AN EXCESS FUEL STARTING DEVICE FOR A FUEL INJECTION ENGINE HAVING A FULL LOAD STOP COACTING WITH THE ENGINE THROTTLE LINKAGE TO LIMIT THE FUEL INPUT THERETO COMPRISING, A HYDRAULIC ACTUATOR OPERATIVELY CONNECTED TO THE FULL LOAD STOP FOR MOVEMENT THEREOF FROM A NORMAL OPERATING FULL LOAD POSITION TO AN EXCESS FUEL STARTING POSITION, SAID ACTUATOR COMPRISING A HOUSING ON THE ENGINE HAVING A CYLINDRICAL BORE THEREIN, A PISTON SLIDABLY DISPOSED WITHIN SAID BORE, AND A PISTON ROD EXTENDING FROM SAID BORE AND OPERATIVELY CONNECTED WITH THE FULL LOAD STOP, A SPRING IN SAID BORE URGING SAID PISTON AND FULL LOAD STOP INTO THE EXCESS FUEL POSITION, A FLUID INLET IN SAID HOUSING OPENING INTO SAID BORE FOR INTRODUCING PRESSURIZED FLUID INTO SAID BORE TO MOVE SAID PISTON AGAINST THE FORCE OF SAID SPRING INTO THE NORMAL OPERATING FULL LOAD POSITION, A FLUID CONDUIT FOR CONNECTING SAID FLUID INLET WITH A FLUID SOURCE PRESSURIZED BY AND ONLY DURING OPERATION OF THE ENGINE, SAID SPRING BEING ADAPTED UPON ENGINE STOPPAGE TO MOVE SAID PISTON AND FULL LOAD STOP TO THE EXCESS FUEL STARTING POSITION, MEANS PERMITTING AN INITIAL INTRODUCION OF FLUID TO BOTH SIDES OF SAID PISTON DURING THE STARTING OF THE ENGINE TO BRIEFLY INHIBIT MOVEMENT OF SAID PISTON, AND MEANS FOR VENTING FLUID FROM ONE SIDE OF SAID PISTON FOLLOWING STARTING OF THE ENGINE TO PERMIT A RAPID MOVEMENT OF THE ACTUATOR INTO THE NORMAL OPERATING FULL LOAD POSITION AND TO MAINTAIN THE FULL LOAD POSITION WITH A MINIMUM PRESSURE OF SAID FLUID.

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