US2381623A - Injector-timer for internalcombustion engines - Google Patents

Description

E. SILBER 2,381,623 INJECTOR-TIMER FOR INTERNAL-COMBUSTION ENGINES Filed July 15, 1942 s Sheets-Sheet 3 LVIIA INVENTOR. [UGE/VE 6/; 55/2.

Aug. 7, 1945.

E. SILBER 2,381,623 INJECTOR-TIMER FOR INTERNAL-COMBUSTION ENGINES Filed July 15, 1942 3 Sheets-Sheet 2 INVENTOR. [Z/GE/VE S/LBER.

I combustion engines, iuel Obviously these pumps would require different ton 1 degree o'iiinterchangeability.

that will-be obvious to those versed in this field of i Patented Aug. 7, 1945 firemen-muss son nv'raanAL- I COMBUSTION enemas Eugene Silbe'r, New Yorln'N. Y.

Application July 15, 1942, Serial No. 451,032

11 Claims.

This invention relates generally to improvements in fuel-supply controls for internal combustion engines and, in a more particular sense. is concerned with a novel injector pump suitable for use on engines of the Diesel type.

It is an object of this invention to provide such a fuel supply which will be simple in its construction and operation and rugged in all its parts, but

' which ,will feed to the engine cylinders the exact amount of fueldesired, and which may be adjusted to meet external conditions with "ease while the engine is running.

pumps of the types now most commonly in use,v

' while the engine is in operation.

It is the chief object of the present invention v,to provide a novel and useful type of injector More specifically it is an object to provide a I device of the above character having a common ,pump for all the engine cylinders but distributing the fuel to the separate cylinders in the orderoi firing by controlled distributing conduit, the

whole having the maximum of simplicity.

As is generally known.;in Diesel-type internal V oil is. forcibly injected into each of the cylinders of the engine in sequence, the order or injection being determined by the type of crank shaft used and the timing oi the successive injections, together with the quantity of fuel injected, beingcontroiled both by the speed at which the engine is operating and the effective working volume of the cylinders. Inasmuch as cylinder-volumes and timing of engines made by diderent manufacturers vary over a wide ,range, say from less than about two hundred seventy cubic inches for small engines up to more 7 than seventeen hundred cubic inches for lars r type mobile engines, it has been customary to design 8.116;,88, with each type of engine, an injector pump particularly suited to its .requirements,

engine,

pump that can be used entirely satisfactorily upon Diesel engines having widely. different requirements as regards volume of fuel injected and the timing of the injections.

Another object of the invention is to provide a pump of the type mentioned which can be easily and economically constructed without requiring use .oi. highly specialized equipment and which, because it includes but a relatively small number of moving parts, is both less subject to wear and easier to repair than certain types of injector pumps now in use.

A further object of the present invention is to provide a incl-control means for internal combustion engines which, in the event of breaking of the governor control bar, or of same bein disconnected from pump for any reason-a ty of accident that is not unco on, will serve to diminish the speed of and eventually stop the instead of increasing the fuel supply and causing the engine to speed excessively and destroy itself as occurs with types of pumps now in use.

A notable advantage oi the injector pump according to this invention over existing types of injector pumps is that the pump plunger is given positive motion by means of a cam mounted upon and operated by the fluid distributor mechanism,

It follows fromthe foregoing that each of the types of injector pumps now in use isunique in the sense that itfunctions with but one type of Diesel engine requiring a peculiar timing 0! injections and specific volume or injected tuel.

may not be used intertypes of engineswhich timing and diiierent vol- Lchangeabl'y upon other umes of injected fuel.

Existing types of injector pumps are mostly ofthecrank shait-driven pishence the latitude within which the eiiective displacement is controlled by ,thestroie oi the shaft. which precludes suillcient adjustment to permit any Also; for reasons invention. .it'is diillcult, it not as a practical matter impossible, to vary the timing of injector.

oi the-pump must be madestructed in a manner such thus permitting the entire apparatus to be conas in occupy but small space, also the same plunger is used to vary or meter the amount of iuel that may be necessary to maintain the speed of the engine and to carry proper: load.

An important feature of this novel injectortimer pump is that adjustment oi the time interval between inlec tions as'is necessary to allow interchangeability oi the pump between different engines, but that it also permits collective advancement of the timing of the injections as the speed of the engine increases without otherwise interfering with the operation oi the p more eflicient operation by minimizing fuel waste.

Other objects, advantages, and features. of the novel injector-timer pump according to thepresent inventionwill be apparent to those versed in this field of invention during the course of thefollowing description.

Regarded in certain of its broaderiaspects; the

it permits not merely the u enginefthus making possible vention comprises a cylindrical block having a plurality of fuel distributor valves therein, successively operable by a common rotating cam element; a variable displacement plunger-type force pump also in said block, connected to a fuel supply and to said distributor valves, periodically operated by means associated with said rotating cam element; means for altering the displacement ofsaid pump; and a valve, controlling the connection of the pump to the fuel supply, for closing the connection periodically while the pump is discharging fuel through the distributor valve.

To facilitate a better understanding of the novel pump according to the present invention and of its mode of operation, a specific embodiment of the invention, illustrated in the accompanying drawings, will now be described, but it is clearly to be understood that this particular application of the principles of the invention is provided by way of illustration merely, not by way of limitation.

Referring to the drawings:

Figure 1 is essentially a side elevational view of a device embodying the principles of this invention; 1

Figure 2 is substantially a horizontal sectional view of the device shown in Figure 1, taken along the line 2-2 thereof;

Figure 3 is essentially'an enlarged side elevational view, partly in vertical sectional view, of the device illustrated in Figure 1;

Figure 4 is substantially a vertical sectional view ofthe device shown in Figure 3, taken along the line 4'4 thereof;

Figure 5 is essentially a vertical sectional view of the device sliown in Figure3, taken along the line 55 thereof;

,Figures 6 and 7 are enlarged detail views showing pump cams and valve operating hinges;

Figure 8 is substantially a vertical sectional view of the device illustrated in Figure 1, taken along the line 8-8 thereof;

Figure 9 is a detail view of a modified plunger head guide for the pump plunger forming a part of the device illustrated in Figure'3; and

Figure 10 is a modification of the discharge valve guide for the plunger pump forming part of the device also illustrated in Figure 3.

Referring now to the drawings which form a part of this specification, and particularly to Figure 1 thereof, it will be noticed that the novel injector timer' pump according to this invention comprises a base number 28 from which extend supporting standards 2| and 22 in the first of which is journalled the drive shaft 23 that operates the device, and in the second of which is mounted, preferably integrally formed therewith, a block, generally designated as 24, that encloses and contains the injector pump proper and the control valves associated therewith. Spacer bars '25, 26, and 21 fastened to the block 24 and the aligned in the desired spaced relationship. I

The block 24, which is substantially cylindrical in shape, is provided with a chamber 28 standard 2|, serve to maintain-the parts rigidly opening through one face of the block but closed at its opposite end, see Figure 3, wherein a closefitting plunger 28 is slidably mounted. It will be noted that-the block is composed of two parts, 24a and 24!), which are bolted together essentially as shown and provided with a suitable gasket to assure proper sealing. The plunger-sis normally urg'ed away from the closed end of the chamber 28 by a, spring 38 that presses against a portion of the block and a collar 3| on the plunger 28. A cap 32, seated in the block 24, engages with the collar 8| thus limiting, the motion of the plunger 28 which can be imparted by the spring 30. A passage 33, formed in the block 24, communicates with the chamber 28 and with the inlet connection of the fuel supply line 34, substantially as shown. A sliding valve 25, slidably mounted in an opening 86 formed in the block 24, is arranged to control fuel flow through the passage 33, and is normally urged into opened position by a helical spring 31 which presses against a portion of the block 24 and an annulus 38 integrally formed upon the stem of the sliding valve 35 essentially as illustrated. A cap 38, seated in the block 24, and engaging with the annulus 38, serves to limit movement of the sliding valve 35 by the spring 81. A dog 40, slidably mounted in an opening 4| formed in the spacer bar 26, abuts against a projecting end portion of the sliding valve member 35, thus permitting movement and operation of the valve by motion of the dog as will be subsequently described.

A plurality of distributor valves 42, 43, 44, 46, 46, and 41, in this instance six in number but correspondingJto the number of cylinders in the engine with which the pump is used, are close fittingly and freely slidably mounted in openings formed in the block 24. Each of the valves differs from each of the others only in its placement in the block, and each is connected to the fuel inlet orifice of a corresponding engine cylinder through the supply lines 48. In each of the connecting supply lines a spring-urged check valve is provided to assure unidirectional fluid flow to the engine cylinders. Referring to Figure 2 of the'drawings, it will be noticed that the typical'valves 43 and 46 are provided with checkvalves 48 and 50 respectively, and that the valves, such as 43 and 46, are normally urged into closed position by springs 5| that press against parts' of the block 24 and annular projectionsupon the valve members. An annular channel 52, formed in the block 24, communicates with each of the valves 42, 43, 44, 45, 46 and 41,, and with the passage 33 communicating with the pump chamber 28, in a manner such that when the pump 28 is reciprocated, fuel from the supply line 34 is drawn into the pump chamber, then forced through the annular channel 52 into one of the engine ylinders through an open distributor valve as will hereinafter be described.

A head 55, mounted upon the shaft 23, is provided with a cam .element 56 arranged to engage with and operate the distributor valves 42,

ating position in Figures 1,2, 3, and 5, and in detail in Figures 6 and 7, are also provided upon the head 55 for operating the injector pump 28 and the sliding valve as will be subsequently described. Referring to Figures 6 and 7, it will be observed that the cam element 64 which is identical with each other cam, comprises a frame operating cam 56 is such that passage 33 into ship upon the head 55 in a circle having its centerpoint coincident with the i axis of rotation of the shaft whereby, as the head is rotated, the camssuccessively operate the pump 29 by striking the end of the pump plunger and press- 1113 the plunger, against the action of the helical spring 3|),into the chamber 28. In each in-' stance, at a small time interval before the plunger isthus moved'by the cam, a frame of the cam diametrically opposite upon the head engages with and moves the sliding dog It against the tension of spring 40a, thus moving the sliding valve 35 from its normal opened position into closed position thereby obstructing the passage 33 and preventing the fuel discharged from the pump chamber from returning to the fuel supply line 34. it of course will be understood that the relative positions of the cams, 60, GI, 82, B3,

64, and 65, together with the distributor valve as the head 55 is rotated the following operations successively occur in this sequence: the cam operating the i sliding dog it disengages from the same,-permitting the spring 31 to move the valve 85 into opened positio thecam pressing the pump plunger 29 into the chamber 28 disengages from the end of the plunger and the spring 30 then moves the plunger in an outward direction, thereby causing fuel oil to be drawn from the supply line 34 through the opened valve 35 and the pump chamber 28; the cam 58 engages with one of the distributor valves l2, 43, 44, 45, 46,.and. 41, moving same into opened position; the frame of one of the cam elements 60, 6I, 62,, 6'3. 84, and 65, engages with the sliding dog thereby moving the sliding valve 35 into closed position one of the cam elements 80, BI, 62, 62, M, and 85, engages with the projecting end portion of the pump plunger is thereby moving same into the chamber 28 and forcing the oil therein into the annular channel 52 from which it passes through the opened-distributor valve to the selected, cylinder; the cam 58 disengages from the distributor valve, permitting same to move into'closed position by action of the spring associated therewith; and the cycle of operations described begins again with'the distributor valve next insuccession.

i It will be obvious that the quantity of fuel injected into the engine cylinders can be altered by adjustment of the stroke of the pump plunger 28. In accordance with the present invention, this is achieved by means of a rotatable'circular endless-wedge cam 10, rigidly mounted upon a shaft H which is journalled in supporting standards 12 and I2 substantially as shown. 'A spring 14, connected to the shaft I l and the support- 13. tends to move the I cam whereby its thinnest portion is normally disposed withinthe peripheral channel lo of the head It for purposes hereinafter described. The cam II, as will be evident in Figures 1 and 8, engages with the projecting ears of the cams ill, il', 82, It, I, and

.65 as each is moved intoposltion to operate the and byrocklng the cams upon iniector pum theirpivotstoadesreedependent n theportion of the. cam I! engalml therewith, the a'moimt of movement of the pump plunger and hence the volume of-'fuel injected, can be accurately controlleddur'ing operation of the gine. The sprin "5 normally holds the cam ll 'in'a position such that the plunger 29 is inoperative; it is shifted from this position only-by the governor as be described. Rotation of the cam Ill is controlled through a coupling member Ii, connected to the engine governor and to an arm 16 mounted on the shaft ll essentially as shown.

It is desirable, when starting a Diesel-type engine or when operating the engine at low speeds minimum fuel injection) to retard the injection time. In accordance with the present invention; this is accomplished by rotating the head upon the shaft 23 which is driven from the engine crankshaft thus retarding or advancing the timing of each of the operations in the sequence above described. To achieve this, a lever arm 80 is provided upon the arm It, which moves when the pump displacement .and fuel injection are altered by rotation of the cam 10. A sliding yoke 8| having a wedge surface 82 thereon, that is, this surface is thicker at its upper right-hand side 82a (as seen in Fig. 4) than ii -its lower left-hand side 82b (as will be seen in Fig. 3). This yoke is coupled with the arm lit whereby, .as the arm moves, the

wedge surface also is shifted. A pair of wedge elements 820 and ,82d, slidably mounted in keyways in the shaft 23 and each is provided with a flange 82a to abut against the wedge surface 82 of the yoke 8| in a. manner such that upon movement of the yoke the wedge elements are shifted in position along the axis of the shaft 23. These members in turn have surfaces II and 84 inclined to the axis which engage mating inclined surfaces on the inside of the head 85 so that this shifting of the wedge elements 820 and-82d along the axis will rotate the head 55 relative to the shaft. A spring 85 presses 7 against the flange 02c and the head 55, whereby the head is maintained in position for-minimum injection timing. It is thus possible to alter the period of injection simultaneously with alteration of the volume of fuel injected, and both while the engine is in operation.

' In Figure 9 a modified form of guide for the pump plunger head is illustrated. The pump or plunger stem is slidably mounted in a block BI and is pressed outwardly by a spring "which engages with a part of the block'and with a projecting annular member." formed upon the stem. A head 94, formed'of hard, wear-resistant material, is freely slidably received in an opening formed in the guide and rests against the end of the stem substantially as shown. This construction is of advantage as the only part subjected to wear, the head 94, can be easily replaced when necessary without requiring replacement of the valve or the plunger. and also prevents distortion of plunger l'l due to striking of cam.

'A similar modification of distributor valve mechanism is illustrated in Figure 10 wherein I the stem 88 is'provided with a cap 01 formed of suitable wear-resistant material and :attached to the stem by a pin 81a. The cap also serves to engage with the spring 92 whereby the stem is urged outwardly.- Asuitable casing ll surrounds thespring thus protecting same from grit and dirt that would interfere with proper operation. and prevents distortion of the plunger head as above mentioned? a V Having thus described the present invention,

what it is desired to secure by Letters Patent is:

1. An internal combustion engine fuel distributor injection pump that comprises a block, a rotatable shaft; a plurality of fuel distributor valves therein concentric with said shaft; a head mounted on said shaft near said block; a first cam element upon said head, constructed and arranged for engaging with and operating successively each of said distributor valves upon rotation of the head; a variable displacement plunger-type injector pump also in said block eccentric to said shaft and adapted to' be connected to a fuel supply and connected to each of said distributor valves; a series of second cam elements upon said head, constructed and arranged each successively to operate the injector pump upon rotation of the head; means for modifying the action of said second cam elements to vary the displacement of the injector pump; a valve in said block for controlling connection of the pump to the fuel supply; and a third cam element upon said head for engaging with and closing said valve when the pump is discharging fuel through the distributor valves.

2. An injector pump for internal combustion engines as described in claim 1 wherein the means for altering the displacement of the pump comprises a circular member having a helical cam surface pivoted to said block, said second cam elements being rotatable in the direction of movement of said shaft and being constructed 2,sa1,eas

fuel from fuel supply and deliver to the cylinders of a Diesel engine, said pump comprising a cylindex and piston eccentric to an axis, a plurality of distributing valves concentrically arranged around about said axis for controlling the delivery of fuel from said pump to the cylinders of the engine in predetermined sequence, a member rotatable about said axis constructed and I arranged to be driven in timed relation-with the crankshaft of the engine, carrying a plurality of concentrically arranged cams positioned to operate said piston once for each cylinder, said rotatable member carrying also a single cam, in position to operate said distributing valves in se-' quence and adjustable means mounted in registry with said piston .for varying the displacement of said piston. u

6. A device in accordance with claim 5, having each of the pump operating cams pivoted to said rotary member and provided with an arm and a stationary but adjustable cam for engaging said arm to vary the displacement of said pump.

7. A device in accordance with claim 5, having each of the pump operating cams pivoted to said rotary member and provided with an arm and a stationary but adjustable cam for engaging said .arm to vary the throw of said pump saidcam and said arm being so constructed and arranged that the adjustment of said cam will vary the displacement of said pump without \making any corresponding variation in the time and arranged to engage said helical cam surface and said pump whereby the displacement of said pump is altered by the adjustment of said circular member about its pivot.

3. A pump for feeding fuel to a Diesel engine adapted to be connected to receive oil from a fuel supply and deliver it to the cylinders of said enginesaid pump comprising a cylinder and piston, a plurality of slide valves concentric about an axis and each slidable parallel to the said axis and each adapted to control the flow of fuel from said pump cylinder to one, of said engine cylinders, a rotary member carrying a plurality of-cams for operating said pump piston and a cam for operating said slide valves, and stationary means for regulating the total movement of said pump piston to vary the feed of fuel.

4. An internal combustion engine fuel distributor-injector pump that comprises a rotatable shaft, a block, a plurality of fuel distributor valves therein, concentric about said shaft, a head mounted on said shaft near said block, a first cam element upon said head, constructed and arranged for engaging with and operating successively each of said distributor valves upon rotation of the head, a variable displacement plunger-type injector pump also in said block eccentric to said shaft, adapted to be connected to a fuel supply and connected to each of said distributor valves, a series of second cam elementof said pump and being constructed and arranged simultaneously to engage said regulating member and said pump, whereby the displacement of said pump is altered by the adjustment of said regulating member, a valve in said block for controlling the connection of the pump to'the fuel supply.

5. A pump adapted to be connected to receive of discharge of said pump. 8. A pump for feeding fuel to a Diesel engine adapted to be connected to receive oil from a 'fuel supply and deliver it to the cylinders of said engine, said pump comprising a cylinder and piston, a plurality of slide valves concentric about an axis and each slidable parallel to the said axis and each adapted to control the flow of fuel from said pump cylinder to the point where it is to be admitted to one of said engine cylinders, a rotary member carrying a plurality of cams for operating said pump piston and a cam for operating said slide valves, each of said plurality of cams including a member movable in the direction of movement of said pump piston and stationary but adjustable means for engaging said movable member to vary the extent to which said movable member moves said piston during the rotation of said movable member and said movable member having a trailin edge constructed and arranged to maintain the exact timing of the close of the piston movement regardless of the adjustment of the piston displacement.

9. A pump for feeding fuel to an internal combustion engine, a block having a piston pump therein, a member rotatably mounted adjacent to said block, having an operating element thereon provided with a pump engaging surface, a cam adjustably fixed on said block for engaging said operating element as the latter engages the piston of said pump to adjust the displacement of said piston, said surface of said operatin element being so constructed and arranged with regard to its pivot that the timing of the moving of the piston is not altered by changing the movement of the operating element to alter the displacement of the piston.

10. A device of the character described comprising a block having a piston pump and a piston valve disposed therein about parallel axes, a member mounted for rotation relative to. said block about an axis eccentric to both the said axes, acam upon said member for operating said block about an axis eccentric to both the said axes, a cam upon said member for operating said valve, and an element movably mounted on said member to engage said pump as said member rotates and a circular cam element mounted on said block in position to be engaged by said movable element simultaneously with said pump, and constructed and arranged to vary the movement of said piston without varying the time thereof. EUGENE SILBER.

Images