US2576694A

US2576694A - Fuel injection system

Info

Publication number: US2576694A
Application number: US335A
Authority: US
Inventors: Ben G Parsons
Original assignee: Individual
Current assignee: Individual
Priority date: 1948-01-02
Filing date: 1948-01-02
Publication date: 1951-11-27
Anticipated expiration: 1968-11-27

Description

Filed Jan. 2, 1948 IN VEN TOR. /T. @risa/75 Patented Nov. 27, 1951 UNIT-ED STATES `PATENT OFFICE FUEL INJECTION SYSTEM en-'Gr.iParsons, Grosse Pointe, Mich.

Application January 2, 1948, .Serial No. 335

7 Claims. 1

This invention relates to improvements in fuel injection systems and more Aparticularly to "improvements in gasoline fuel'injection systems for multi-cylinder engines.

One of the primary objects of the present invention is to provide improvements in systems of the type mentioned wherein gasoline may be distributed to a multiplicity `of cylinders in a'system employing a single pump and distributor. A further object of the invention is to provide improvementsv in systems of the type mentioned wherein the pump may be mounted in any convenient location land does not need to be mounted closely adjacent the engine cylinders and the necessity ot a transfer pump is eliminated,

A further object of the invention is to provide improvements in systems of the type mentioned wherein means is provided which is responsive to the engine manifold pressure so as to vary'the output of the aforementioned fuel pump. .A still further object of the invention isto provide improvements in systems of the type mentioned wherein there will be high delivery at low manifold pressure and low delivery at high manifold pressure.

A still further object of the invention'is to provide, in the aforementioned manifold pressure responsive means, a high engine speed adjustment, and idling speed adjustment.

Other objects of the invention will become-apparent from the following specication, the drawings relating thereto, and from the claims herelnafter set forth.

In the drawing in'whichlike numerals are used to designate like parts in the several view throughout:

Figure l is a diagrammatic view ofthe mclin- `jection system according to .the present invention and showing the pump, distributor, and pressure responsive means, and the relation of the same to each other and to the fuel tank and injector nozzles; and

Fig. 2 is a vertical cross sectional view ofthe distributor employedin Fig. 1.

Referring to the drawing, a fuel supply tank is indicated at 3 having a pump generally indicated at^5 mounted thereon. The pump is con`v` nected to a vdistributor generally indicatedA at I through a flexible conduit 9, andthe, distributor is connected to a plurality of .injector nozzles II through flexible conduits I3. Thenozzles Il may be ofthe type disclosed in the copending application of Ben G. Parsons, Serial No. 546,352,1iled July 24, 1944, now abandoned, or'may be an open end tube.

The pump 5 comprises a housing I5 formedwith a longitudinally extending inlet passageway l1. An inlet port I9'is located intermediate the ends of the housing I5 and communicates with the inlet passageway If'I and also communicates through an inlet tube 2-I with the interior-of the tank 3. The

ltube 2|, of course, extends to a position adjacent sageway I'I'and the bores 23 and 25 extend through the ends of the housing I5 within recessed portions 2'l and 29. An end plate 3l is fixed to one end Vof the housing and forms, between the 4inner face thereof and the recess y21, an inlet chamber communicating the adjacent end of the passageway Il with the adjacent ends of thebores 23 and 25. An end member 33 is removably attached to the opposite end of the housing I5 and is spaced from the recess 29 to provide an inlet chamber between the inner face thereof and recess 29 which communicates with that end of the passageway I'I and with the adjacent ends of bores r23 and 25.

A pair of intermeshing pump elements 35 and 31 are disposed within the bores 23 and 25 respectively. Each of the pump elements 35 and 3l is threaded with a lead extending from the outer ends of the elements toward the center thereof Where the threads open into reduced portions 39 and 4I. 'The outer ends of the threads ofthe pump elements communicate with the inlet chambers opposite the ends of the housing I5. The reduced portions 39 and 4I form with the adjacent peripheries of the bores 23 and 25 an outlet chamber vv-hich communicates through an outlet port43 with conduit 9 which is attached to the housing l'adjacent the outlet '43 by means of a fitting'44'.

One of the pump elements, for example, .element 35, is driven by an electric motor 45 which is connected to the end member 33. The motor has lits drive rshaft received within a suitable bear ing mounted in the member A33 in axialalign', ment` with the element 35. The motor shaft is coupled to an inwardly projecting end 49 of the eiement35 by means of a coupling indicated at 5 I'.

A manifold. pressure responsive unit, generally indicated at 53, is provided for controlling the speed of the motory d5'. The unit 53 consists of a hollow housing '55 having an enlarged recess -5-1 formed in one end thereof. The Wall of the hous ing 55', at the. enlarged end` thereof, isiformedfw'ith an outturned annular lflange 59. An end cap `Iii is secured to the enlarged end of the housing 55 by means of a reversely bent annular flange 63, which embraces the housing flange 55T- The end cap 6I is formed with an outwardly projecting, externally threaded, hollow nipple 'S5 whichhas a central aperture G'I'in the end wall' thereof. The nipple is adapted to be threaded 'into anr opening in an engine manifold so as to connect lthe housing to the latter. A calibrated, bellows-type diaphragm 69% is disposed within thev enlarged alignment with the aperture 61 of the nipple 65.

A rheostat 10, which includes an electrically conductive metallic rod 1I is secured to the opposite end of the diaphragm 69, and is insulated therefrom by suitable insulation 13. The remote end of the shaft 1| is embraced by a winding of wire,

15 so as to form the rheostat 19, which is disposed centrally within the housing 55. Other forms of rheostats may be employed, the specific one shown being for the purpose of illustration.

An end cap 11 is threadably connected to the small end of the housing 55 and is provided with an outwardly projecting central boss 19, having an aperture 8| therethrough. A pin or stud 83 has its inner end iixedly connected to the adjacent end of the rheostat 10. Suitable insulating material 85 insulates the end of the pin 83 from the rheostat. A coil spring 81 surrounds the inner end of the pin 83 and has its inner end abutting the end of the rheostat 19, and its outer end abutting the end wall of the cap 11. The outer end of the pin 83 projects outwardly through the central aperture SI of the end cap boss 19 and is threaded at 89. A hollow, elongated, nutlike member 9| is threadably connected to the outer end of the pin 83, and the inner end of the member 9| is formed with an enlarged recess 93. The outer end of the end cap boss 19 is disposed within the recess 93 and formed with an outturned fiange 95,

which slidably engages the wall of the recess 93. Thus the member 9| can slide longitudinally with respect to the end cap 19, and can be adjusted with respect thereto by threading it inwardly or outwardly on the pin 83.

A pair of longitudinally spaced stationary contacts 99 and I9| are disposed within the housing 55 so as to engage the rheostat 19. The stationary contact 99 is connected to one terminal of the electric motor 45 Vby means of a wire |03 and battery |05. The contact |0I is connected to the opposite terminal of the motor 45 through ya wire |01. The wire |91 is provided with a switch |89 which closes only when the engine-ignition is turned on, and is open when the same is olf. A second switch III is provided in line |91 which closes when the engine is started and a predetermined engine oil pressure obtained. In this way the motor 45 will not be operated unless the ignition is on, and the engine is actually started, and oil pressure obtained.

The distributor 1 comprises a housing ||3 having a central aperture II5 extending longitudinally therethrough and a distributor plate IIG connected to one end face thereof. The plate I6 Ais provided with an inlet port II1 which communicates with the housing central aperture I I5, and with the conduit 9 through a fitting |I9. A distributor element |2| is disposed within the housing aperture I I5, and rotatably supported in the housing by bearing |23 and snap ring |25. One end of the distributor element I2I is provided with a universal coupling '|29 for connection with suitable drive means, such as the engine cam shaft for properly timing the distribution oi the fuel to the cylinder. The distributor element |2| is provided at the opposite end from the coupling |29 with a central longitudinally extending recess I3I which communicates with the inlet port I |1, so as to be filled with the fuel from the pump 5. The wall of the distributor element I2| is provided with an opening |33 which communicates with the recess' 3|. A plurality of circumferentially, equally spaced passagewaysA are provided in housing I3 which communicates singly with the distributor opening |33, during rotation of the distributorA element |2I. The housing passageways |35 communicate with outlet ports |31 in the distributor plate IIB secured to the end face of the housing II3. The outlet ports |31 communicate with the conduits I3 through suitable fittings so that upon rotation of the distributor element |2| by, for example, the cam shaft of the engine, the fuel will be discharged through the outlet ports |31 to the nozzles II, in timed relation to the engine so as to properly inject the fuel into the cylinders at the proper time. A groove |40 is provided in the housing, around the aperture II5, for trapping any leakage of fuel and a conduit |4| communicates with the grove |49 and is connected to the intake air manifold. In this way this small amount of fuel is sucked into the manifold by vacuum so as to obviate fuel losses. The wall of the rotary distributor |2| is relatively thin so that it will expand under internal pressure against the wall of the bore preventing leakage. Also, the wall can contract to prevent sticking.

In operation of the system above described the distributor element I2! is driven in timed relation from the engine cam shaft, for example, and the motor 45 is operated at the proper operating speed by the unit 53. When the engine is at idling speed, the manifold pressure is at its lowest point and the manifold vacuum at its highest point so that the diaphragm bellows 69 of the unit 53 is collapsed and the rheostat 10 will move to the right, as viewed in Fig. 1, due to the spring 81. When the rheostat 10 moves to the right the winding 15 will increase the resistance between the stationary contacts 99 and I9I and cause the speed of the motor 45 to be reduced to its minimum, so that the fuel delivery from the pump 5 to the distributor 1 is at a minimum. The amount of movement to the right of the rheostat 19y can be adjustably controlled by means of the nutlike element 9|. By threading the nut element 9| inwardly or outwardly on the pin 83, the movement to the right of the rheostat 10 can be controlled. As the nutlike member 9| moves With the pin, it will abut the outer face of the end cap 11 in accordance with the its threaded position on the pin 83, so that the minimum speed of motor 45, for idling speed of the engine can be properly adjusted.

When the engine is running at wide open throttle, the manifold pressure is at a maximum and the manifold vacuum at a minimum so that the diaphragm bellows 69 is expanded its full amount, thus moving the rheostat 10 to the left as viewed in Fig. 1, 'and reducing the resistance between the stationary contacts 99 and I 9 I. This causes the motor 45 to rotate at its maximum speed so that the maximum fuel delivery from the pump 5 to the distributor 1 is obtained. The amount of movement of the rheostat 19, to the left, can be controlled by threadably adjusting the vend cap 11 on the housing 55 so as to vary the value of the spring 81. In this way the maximum speed of the motor 45, for high speeds of the engine can be adjustably controlled to insure the proper fuel delivery for wide open throttle of the engine. The bellows 69, of course, will expand or collapse in varying degrees between engine idling speed and wide open throttle, so as to automatically synchronize the speed of the motor 45 and therefore the fuel delivery from the pump to the distributor, in accordance with the` manifold pressure.

The operation of the motor 45 at the proper speed causes rotation of the intermeshing pump elements 35 and 31, and withdraws gasoline from the tank 3 through the inlet port I9 into the passageway |1. The fluid passes toward both ends of the passageway into the inlet chambers around the opposite ends of the pump elements 35 and 31. The iiuid is pumped into the outlet chamber surrounding the reduced portions 39 and 4| and out through the outlet port 43 under pressure into the distributor inlet port ||1, through the conduit 9. Since the pressure adjacent the end members 3l and 33 is under atmospheric pressure there will be no leakage of fuel through these parts. Furthermore, when the pump is not operating the fluid will merely drain back under no pressure to passageway l1 and back through the tank.

In certain instances it may be desirable to have the device sensitive to the engine speed as well as the manifold pressures. This may be accomplishd by loading the spring 81 through the action of a governor suitably connected to a speed responsive element on the engine or by raising or lowering the distributor plunger l2| through the action of the governor. In this case the opening |33 would be tapered on the longitudinal axis rather than round.

Formal changes may be made in the specific embodiment of the invention described without departing from the spirit and substance of the invention, the scope of which is commensurate with the appended claims.

I claim:

1. In a fuel injection system for a manifoldtype engine, an injection nozzle, a fuel distributor connected to said nozzle, a fuel pump connected to said distributor, variable speed drive means independent of the speed of the engine for driving said pump, and means responsive to manifold pressure for varying the driving speed of said drive means.

2. In a fuel injection system for a manifoldtype engine, an injection nozzle, a fuel distributor connected to said nozzle, a fuel pump connected to said distributor, variable speed drive means independent of the speed of the engine for driving said pump, and means responsive to manifold pressure for varying the driving speed of said drive so as to increase the pump output at high manifold pressure and decrease the pump output at low manifold pressure.

3. In a fuel injection system for a manifoldtype engine, a multiplicity of injection nozzles, a conduit connected to each nozzle, a fuel distributor having outlet ports communicating with the conduits, said distributor having an inlet port, means communicating said inlet port with said outlet ports in succession, a fuel pump separate from said distributor, a conduit connecting the pump outlet with said distributor outlet, an electric motor independent of the speed of said engine driving said pump, and means responsive to manifold pressures for varying the speed of said electric motor independently of engine speed whereby to increase the speed of said motor at high manifold pressures and decrease the speed of said motor at low manifold pressures.

4. In a fuel injection system for a manifoldtype engine, an injection nozzle, a fuel distributor connected to said nozzle, a fuel pump connected to said distributor, an electric motor independent of the speed of said engine driving said pump, variable impedance means for varying the speed of said electric motor, and diaphragm means operatively connected to said variable impedance means and responsive to manifold pressures for varying said impedance means and therefore the speed of said electric motor independent of the speed of said engine.

5. In a fuel injection system for a manifoldtype engine, an injection nozzle, a fuel distributor connected to said nozzle, a fuel pump connected to said distributor, an electric motor driving said fuel pump, a bellows-type diaphragm responsive to engine manifold pressures, variable impedance means operatively connected to said diaphragm, and current conducting means connecting said electric motor and said impedance means.

6. In a fuel injection system for a manifoldtype engine, a multiplicity of injection nozzles, a conduit connected to each nozzle, a fuel distributor having outlet ports communicating with the conduits, said distributor having an inlet port, means communicating said inlet port with said outlet ports in succession, a fuel pump separate from said distributor, a conduit connecting the pump outlet with a distributor inlet, an electric motor independent of the speed of said en- -gine driving said fuel pump, a housing, a bellowstype diaphragm having one end thereof connected to said housing, said housing end being connectible to said engine manifold whereby said bellows diaphragm is responsive to manifold pressures, variable resistance means operatively connected to the opposite end of said bellows so as to be movable therewith, stationary contact means engaging said variable resistance means, and current conductor means connecting said stationary contact means to said electric motor, whereby the operation of said diaphragm in response to said manifold pressures will increase the output of said fuel pump at high manifold pressures and decrease the output of said' pump at low manifold pressures.

7. In a fuel injection system for a manifoldtype engine, an injection nozzle, a fuel pump connected to said nozzle, variable speed drive means independent of the speed of said engine for drivin-g said pump, and means responsive to manifold pressure for varying the driving speed of said drive means.

BEN G. PARSONS.

REFERENCES CITED The following references are of record in the file of this patent:

UNITED STATES PATENTS Number Name Date 1,376,841 Iirrill May 3, 1921 1,597,787 Hausser et al. Aug. 31, 1926 1,745,130 Turner Jan. 28, 1930 2,126,709 Alden Aug. 16, 1938 2,236,553 Voit et al Apr. 1, 1941 2,414,617 Summers Jan. 21, 1947 2,439,498 Wallace Apr. 13, 1948 FOREIGN PATENTS Number Country Date 865,115 France Feb. 10, 1941 551,308 Great Britain Feb. 17, 1943