US2432507A - Fuel injecting pump - Google Patents

Description

Dec. 16, 1947. J. A. CIVITARESE 2,432,507

FUEL INJEC'IING PUMP Filed Jan. 21, 1944 5 Sheets-Sheet 2 J. A. CIVITARESE FUEL INJECTING PUMP Filed Jan. 21, 1944 5 Sheets-Sheet 3 (am/magenta? Pal)! J G igzlgggr O C) Dec. 16, 1947. J. A. CIVITARESE 2,432,507

FUEL INJECTING PUMP Filed Jan. 21, 1944 5 Sheets-Sheet 4 A! A 37 J2; 4

Patented Dec. 16, 1947 FUEL INJECTING PUMP Joseph Anthony Civitarese, Lodi, N. J. Application January 21, 1944, Serial No. 519,173 9 Claims; (01. 103-173) The present invention relates to fuel injecting pumps, and more especially to those of the class employed for injecting fuel into the cylinders of internal combustion engines.

One of the primary objects of the invention is to provide a novel and improved liquid fuel injecting pump whereby the amount of fuel injected into the engine cylinders may be readily.

adjusted to control the power developed by the engine, and in which the fuel is distributed to the engine cylinders by a single rotating valve.

A more particular object is to provide a multiple pump for feeding liquid fuel, the pump units being simultaneously and uniformly adjustable during their operation to vary the amount of fuel supplied by each pump unit, and a single distributor valve which receives the fuel from each pump unit and distributes it to the engine cylinders.

Another object is to provide a multi-pump feed for multi-cylinder engines in which the pump units are actuated by a single cam member having cams arranged thereon to time the operations of the pump units properly in relation to the cylinders to which the fuel is being fed, the arrangement of the cam enabling a multiple number of engine cylinders to be fed from a smaller number of pump units.

A further object of the invention is to provid a combined fuel injecting'and ignition plug for the engine cylinders which not only provides a unitary structure for these functions but which introduces the fuel into the engine cylinder adjacent to the point of fuel ignition, thus rendering ignition of the rejected fuel charges more certain, effective and uniform.

In the accompanying drawings,'which disclose the preferred embodiments of the invention:

Fig. 1 is an elevation of one form of fuel injecting means, comprising the improved multipump and distributor valve, and showing the improved fuel injecting and ignition plug for one of the engine cylinders.

Fig. 2 is a top plan view of the pump and distributor. Y

Fig. 3 is a vertical section of the pump and distributor/valve, taken through two of the pump units. i

Fig. 4 is a horizontal section, taken on the line 4-4 in Fig. 3 and looking in the direction of the arrows.

Fig. 5 is a horizontal section, taken on the line 5-5 in Fig. 3 and looking in the direction of the arrows.

Fig. 6 is a horizontal section, taken on the line 66 in Fig. 3.

Fig. 7 is an enlarged detail section, taken on the line 1-4 in Fig. 2.

Fig. 8 is an enlarged detail section of the upper portion of one of the pump units and adjacent parts.

Fig. 9 is a transverse section, taken on the line 99 in Fi 8.

Fig. 10 is a detail section, taken on the line l0l0 in Fig. 3.

Fig. 11 is a detail section, taken on the line ll-Il in Fig. 3.

Fig. 12 is a perspective view of the upper end of one of the pump plungers.

Fig. 13 is an enlarged detail section taken longitudinally through one of the fuel'injecting and ignition plugs, and Figs. 13a. and 13b are detail views of the check valve.

Fig. 14 is a bottom plan of the plug shown in Fig. 13.

Fig. 15 is a diagram illustrating the number and arrangement of pump units and cams employed for feeding fuel to different numbers of engine cylinders.

Fig. 16 is a vertical section of a modified form of fuel pump and distributor according to the present invention.

Fig. 17 is a section, on an enlarged scale, taken horizontally through the pump structure shown in Fig. 16.

Fig. 18 is a vertical section of one of the pump units employed in Fig. 16.

Fig. 19 is a detail view of the cams for regulating the fuel feed from the pump units.

Fig. 20 is a detail view, illustrating the by-pass valve for one of the pump units, and showing the controlling cam in cooperation therewith.

Figs. 21 and 22 are detail perspective views of ,the cam elements for regulating the fuel feed from the pump units.

Fig. 23 is a diagrammatic view showing the relative timing of the pump actuating and fuel regulating cams employed in the arrangement shown in Fig. 16.

Fig. 24 is a section taken vertically through the upper portion of the multiple pumpi shown in Figkl, illustrating a lubricating system therefor.

Fig. 25 is a section taken vertically through the upper portion of the multiple pump shown in Fig. 16, illustrating a lubricating system therefor.

The preferred embodiments of the invention are shown in the. drawings and are hereinafter described in detail, but it is to be understood that.

the invention is not restricted to the precise details shown, as equivalent structures are contemplated and such will be included within the scope of the claims at the end of this specification.

Referring first to he embodiment of the invention shown in Figs. 1 to 15 inclusive, the multiple pump comprises a casing I which contains the pum units and distributor valve and their actuatin and controlling means. Different num- I thereto.

bers of pump units may be employed, a group of four of such units being shown, for example, in the present instance, the fuel outputs of which are distributed to the respective engine cylinders by a single or common distributor valve. The pump units are grouped concentrically and spaced at equal angles around the center of the casing.

Each pump unit comprises a cylinder 2 fitted in a bore in the casing and secured adjustably therein by a locking screw 3, the cylinder having an enlarged head 4 which fits closely in an enlarged portion of the bore, and a plunger 5 which fits and reciprocates in the cylinder. The upper portion of the cylinder is provided with a fuel inlet port 6 and a fuel outlet port I, these ports be'ng uncovered by the plunger when it approaches the end of its downward or intake stroke, the port 6 communicating with an inlet passage 8 in the head 4 and the port 1 communicating with an outlet port 9 in said head. The upper or discharge end of the cylinder is open and communicates with a discharge port 10 controlled by a check valve II which permits discharge of fuel from the pump but prevents return flow of fuel The port in .and eontinuations of the passages 6 and I are formed in a head plate 12 which is surmounted by a cap I3, said plate and cap being firmly secured together and to the top of the casing as by cap screws l4 or other suitable means. Each valve II is urged toward its seat on the late 12 by a spring l5 which is compressed between the valve H and cap l3. The plate i2, as shown in Fig. 5, is also provided with a central port l6, and an annular series of ports I! which are concentric therewith and are of a number corresponding with the number of cylinders of the engine to which the fuel is to be fed.

The underside of the cap l3, as shown in Fig.

4, is provided with an inner annular groove l8 which communicates, by a passage [9, with a fuel supply pipe 20, and is provided with an outer annular groove 2| which communicates, by a passage 22, with a fuel outlet pipe 23 which may be connected toreturn fuel therefrom to the source of fuel supply; The underside of the cap I3 is also formed-with chambers 24 for the springs munioate'with passages 28 which lead to fittings 29 to which are attached pipes 30 for conducting the fuel to the respective cylinder .of the engine. The head plate I2 is provided in its underside with a recess in which a circular valve 3| is fitted, the top of this valve seating against the top of the recess in the plate [2 and the valve having a bevelled flange 32 which rests ona corresponding seat formed on the surrounding upper end of a cylindrical bore 33 formed centrally. within the pump casing. The top of the valve 31 is provided with a central port 34, which registers and is in constant communication with the central ports 16 and 26, and with a port 35 which,'during rotation of this valve, communicates successively with the ports I! in the head plate, the ports 34 and 35 being connected by a radial passage 36 formed within the valve 31. This valve is connected to the upper end of a shaft 31 to be rotated thereby, and is pressed against the head plate l2 to maintain a fluid tight fit therewith by a spring 38 the The plunger 5 of each pump unit is of the type having an upper cylindrical portion 5 which has a fluid-tight fit in its respective cylinder, and this portion of the plunger is formed with a tapered groove 5 the narrow end of which communicates with the top thereof, one side of this groove having a helically extending edge 5 which extends around one-half of the circumference of the plunger, said groove being adapted to communicate with the port 1 earlier or later in the upward or discharge stroke of the plunger, according to the position into which the plunger is rotated, thereby regulating or metering the amount of fuel injected at each working stroke. Each plunger is actuated on its working stroke by a tappet 4| which is mounted slidatly in a guide sleeve 42 fixed in the casing and carrying a screw 43 which is engageable with the lower end of the plunger, the tappet carrying a roller 44 rotatable on a pin 45 the ends of which project into slots 46 in the guide sleeve to prevent rotation of the tappet in its guide sleeve. The return strokes of each plunger are effected by a spring 47, which maintains the respective tappet roller in operative relation with an actuating cam 50, the latter being provided on its upper face with cam p10- jections 5| of a number and arrangement accordingto the number of cylinders of the engine supplied with fuel from the pump. The cam 53 is keyed or otherwise fixed to the lower portion of the shaft 31, which latter is driven from the engine in proper timed relation therewith, as at cam shaft speed when used with an internal combustion engine of the conventional four-cycle type. The shaft 31 is supported rotatably in the pump casing by upper and lower bearings 52 and 53, and by a bearing 54, preferably of the antifriction type, interposed between the cam and a cap 55 which is removably secured, as by the cap screws 53, to the bottom of the casing.

Means is provided for simultaneously and uniformly rotating the plungers of the pump units to regulate or meter the fuel'injected by the group of pump units, such meanscomprising a pinion mounted rotatably on the lower end of the cylinder 2 of each unit and having a sleeve 60 extending downwardly therefrom and provided with a pair of diametrically opposite slots iii in which the ends of a pin 62 extending diametrically through the respective plunger reciprocate, this pin connecting, the pinion to the respective plunger so that rotation of-the pinion causes corresponding rotation of the plunger. The pinion is held in position against a bushing 63 by the spring 41 which effects the return strokes of the plunger. "The pinions 60 of all of the pump units mesh, with a central gear 64 which is mounted loosely on the shaft 31 and may be supported by an antifriction bearing 65 interposed between this gear and the bearing 52, and the gear M has a pinion 66 fixed thereto, this pinion meshing with a reciprocatory rack 61 which is slidable in bearings 68 in opposite sides of the casing and adapted of 135 degrees, as indicated in the lower portion of Fig. 15, and such a pump may be adapted to a twelve cylinder engine by employing a cam 50 having three cam projections 5| spaced apart through equal angles of 120 degrees, as indicated at the bottom of Fig. 15. When the pump comprises two pump units in diametrically opposite relation, as indicated in the upper portion of Fig. 15, such a pump may be adapted for injecting fuel for a four-cylinder engine by employing a cam 50 having two cam projections spaced apart through an angle of 90 degrees, andmay be adapted for use with a six cylinder engine by employing a cam 5|] having three cam projections 5| spaced apart through equal angles of 120 degrees. Similarly, by employing a pump having three pump units spaced around the central actuating shaft 3'! through equal angles the plug body containing a core 1| of insulating material through which a central electrode 1| extends to a position to cooperate with one or more electrodes 12 grounded on the plug body, as usual, for igniting fuel in the engine cylinder, this electrode contacting with a lead wire |1| for supplying ignition current to the plug, the lead wire being secured in the top of the plug in any suitable may, as by an insulating sleeve I12 and retaining cap I13. The plug body is bored to provide a passage 13 which leads downwardly to a chamber 14 the lower end of which is provided with a plug 15 having an orifice 16 immediately adjacent to the plu electrodes, and through which the fuel is injected into the engine cylinder.

Means is preferably employed for preventing after-drip of any fuel after injection has ceased. Such means, as shown in the present instance, comprises a check valve 11 having a plurality of grooves 11 in its periphery and extending from its upper to its lower end. This valve is movable axially within the cylindrical chamber 14, and is tapered or otherwise suitably formed on its upper and lower ends to seat on either an upper valve seat 10 or a lower valve seat 15 a spring 18 being provided which surrounds a reduced portion of the valve and acts on the valve to engage it with the upper seat. The surface of the lower tapered end of the valve is provided with a suitable number of grooves 11 which extend inwardly from its periphery toward and in tangential relation to its center where these'grooves communicate with the upper end of the orifice 16 in the plug. In operation, the upper end of the valve 11 is held seated against its upper seat 10- by the spring, but as the fuel is forced downwardly in the passage 13 it forces the valve downwardly, thereby disengaging it from its upper seat and permitting the fuel to pass down through'the grooves 11 and into the portion of the chamber 14 containing the reduced portion of the valve and the surrounding spring 18. This downward movement of the valve continues until its lower end seats on the lower valve seat 15 on the upper end offthe plug 15, but the flow of the fuel continues through the tangential grooves 11 which communicate with the plug for insertion into the cylinder of the engine,

orifice 16, the consequent tangential flow of the fuel producing a turbulent motion thereof as it enters the orifice. When the pressure on the fuel in the fuel line ceases, the spring 18 returns the valve to its upper seat 10, thereby preventing any pressure due to compression or combustion in the engine cylinder from producing back pressure against the fuel in the line leading to the fuel injecting plug. The valve 11 thus acts as a pre-check valve in advance of the ball check valves 9| and 95 of the fuel injecting plug unit, to eifectively prevent backpressure on the fuel in the fuel line, the movement of the valve 11 being relatively small or minute.

A bushing 8|] is threaded or otherwise secured in the body 10 of the plug so that it seats on the! bottom of a recess therein having an annular fuel supply groove 8| which communicates with the passage 13, this bushing having a passage 82 therein which communicates with the fuel supply groove 8|. The bushing is formed with a seat 83 which is provided with an annular fuel supply groove 84, and said seat is adapted to receive a. fitting 85 which is clamped thereon as by a nut 86 threaded on the upper endof the bushing. The fitting 85 has a lateral extension 81 provided with a chamber 88 into which a plug 89 isfitted. said chamber being provided with a passage 90 which communicates with the fuel supply groove 84. The plug 89 contains a check valve 9| having a spring 92 for normally holding it on its seat to prevent return of fuel from the engine cylinder. A pipe fitting 93 is attached to the end of the extension 81, as by a nut 94 threaded thereon, and this fitting is also preferably provided with a check valve 95 and spring 96. The fitting 93 is connected to one of the pipes 30 to receive fuelfrom the pump and supply it to the respective cylinder of the engine.

The present invention also provides as a single unit a combined fuel pump and ignition timer and distributor, which enables the same shaft to be utilized for the operation of both. the fuel pump and the timer and distributor. As shown, the timer and distributor I00, which may be of usual or conventional form, is arranged at an oblique angle to the axis of the pump casing, its shaft being connected to and driven from the shaft 31 by a bevel gear ||1| thereon which meshes with a similar bevel gear I02 on the shaft of the timer and distributor.

The operation of the pump and distributor as shown in Figs. 1 to 15 inclusive is as follows: Assuming that liquid fuel is supplied to the pump through the pipe 20, and that the shaft 31 is driven from an appropriate part of the engine in proper timed relation therewith, the liquid fuel-will be fed through the passage l9 to they inner groove l8 and from this groove to the inlet passages 8 leading to the intake ports 6 of the pump units. Each time one of the cam projections 5| is brought beneath a pump unit by rotation of the cam 50, the plunger 5 of such unit will be lifted by its tappet 4|. During the initialpart of the upstroke of the plunger, the fuel in the cylinder above it will be forced upwardly, opening the valve II and entering one of the passages 25 and flowing to the central port 26. The fuel then passes to the central port 34 and through the radial passage 36 to the port 35 in the valve 3|. As the valve 3| is rotated in timed relation with the pump units throughthe shaft 31 which drives it and the cam 50, the port 35 in the valve will register with one of the dis- 7 tributor ports H from which the fuel is conducted through the port 27 and passage 28 and by the respective pipe 39 to the injector and ignition plug of the corresponding engine cylinder, the fuel unseating the check valves 95 and 9| and flowing through the passages 90 and 82 and chamber I4 and discharging into the cylinder through the orifice I5, where it is ignited by the spark passing at the appropriate time between the electrodes I I and I2.

The amount of fuel injected into each cylinder by each pump unit is controlled by adjustment of the rack bar 6'! which rotates the pump plungers simultaneously to alter the relation of the helical edge of the groove 5 of each plunger to the by-pass port of the respective cylinder. When this helical edge of the groove comes into communication with the respective by-pass port I during the upward or working stroke of each plunger, the fuel in the respective cylinder flows from the upper side of the plunger through the groove 5 and discharges into the by-pass port I, thereby terminating the discharge of fuel past the check valve I I, thereby metering or regulating the amount of fuel injected into the engine cylinders by the respective pump units. When the cam projections 5| each pass from beneath each pump plunger, the latteris lowered by its spring 41, the respective check valve II then being closed, so that fuel is drawn from the inlet port I of the respective pump unit when it is uncovered by the descending plunger. As the ignition timer and distributor is driven in synchronism with the pump, the fuel charges will be ignited simultaneously with their introduction into the respective engine cylinders. Adjustment of the rack bar 6'! operates through the pinion 66 and gears 64 and 60 to rotate the pump plungers simultaneously and to equal extents to vary the relation of the helical groove 5 of each plunger to its port I, causing fuel above the plunger to by-pass into said port at an earlier or later point in its discharge stroke, thereby metering the fuel injected into the engine cylinders, according to the position of the rack bar.

In the modified form of the pump shown in Figs. 16 to 20 inclusive, the pump plungers 5 four of which are shown, are fitted to reciprocate in cylinders 2 fixed in the pump casing I, as by bushings 2 threaded into the casing and forcing the cylinders into the casing with a taper fit. The pump plungers are reciprocated by tappets II actuated by a cam 50 fixed on an extension I 59 of the shaft 31 and having cam projections 5| thereon for actuating the plungers.

The cylinder of each pump unit is open at its upper end and communicates with a port III in a plate I?- and provided with a check valve H and spring I5 in chambers 24 in a cap I3 these chambers being connected by radial, passages 25. in the cap leading to a central passage 26, the latter communicating with a central port 34 in a circular bevelled valve BI mounted rotatably between the upper end of the casing I and the plate I2? The valve 3| has a radial passage 36 leading from its central port to a port 35 which communicates successively with ports II arranged in an annular series in the head plate I2, which register with a correspondarrangement to Figs. 1 to 15 inclusive, and they function in a similar manner to distribute the liquid fuel to the different cylinders of the engine, but the means for metering or regulating the amount of fuel injected by the pumps is somewhat difierent.

As shown in Fig. 18, the cylinder of each pump unit is provided, near its upper or discharge end, with a port I which communicates, through a passage 9, and check valve III) with a central chamber III in the upper portion of the casingbelow the valve 3|, and which is connected to receive liquid fuel through a feed pipe I I2 and passage H3. The valve I I0 is pressed toward its seat by a spring I I4, and is provided with an upwardly projecting stem H5. The shaft 3! to which the valve 3|- is fixed, is mounted in bearings H6 and H7 located centrally in the casing, a suitable packing H8 being inserted in a chamber H9 surrounding the shaft and retained by a nut I20 to prevent leakage of fuel from the chamber III.

A set of tappets I20 is mounted for vertical movement on a disk I22, mounted rotatably in the upper end of the chamber H9, the tappets correspondin in number to the number of pump units, and being arranged in an annular series and guided for individual vertical movements by vertical pins I2I secured in the disk I22, one of these tappets overlying the stem H5 of each valve H0. The disk I22 is connected to a gear I23 for rotation therewith, as by a hub I24 through which pins I25 fixed to the tappets extend, an antifriction bearing I26 being preferably interposed between the gear I23 and the valve 3I against which said gear is pressed by a spring I22. The shaft 3'I carries a cam I21 which rotates therewith and is provided with a suitable number of cam projections I28 arranged to engage and depress successively the pins I25 which project inwardly from the tappets. When, as shown in the present instance, the pump comprises four pump units, and the pump actuating cam 5i] is provided with two cam projections 5| spaced apart through an angle of 135 degrees, two cam projections I 28 spaced apart through a similar angle of 135 degrees and synchronized with the cam projections 5| will be sufilcient for an eight cylinder engine, and three cam projections I28 equidistantly spaced apart through angles of degrees will be sufiicient for a twelve cylinder engine.

The tappets I20 are normally held in raised position by the springs H4 of the respective valves III] the upwardly projecting stems II5 of which engage the undersides of the respective tappets, but as the cam I21 is rotated by the shaft 37, it successively engages the pins "I25 on the tappets and lowers the latter, thereby pushing open the respective valves H0, thus permitting liquid fuel to be by-passed or returned from the respective pump units to the supply chamber II I. The cam I2'I is so timed on the shaft 31 in relation to the cam 50 that its projection I28 will depress each valve I I0 durin the fuel discharge stroke of the plunger of the respective pump unit, thereby permitting fuel to be by-passed from the upper side of each pump plunger through the respective port 1*, passage 9 and valve H0 into the chamber III.

In order to enable the amount of fuel by passed from each pump unit during the working strokes of its plunger, and to thereby meter or regulate the amount of fuel injected during the working strokes of the pump plungers, the gear I23 is the passage 9 and port 1*.

rotatable into different positions by means lo cated exteriorly of the pump casing, it being preferable to employ a bevel pinion I30 which meshes with the gear I23, this pinion being formed on the inner end of a stem I3I which is preferably of tapered form and fitted rotatably in a bushing I32 threaded in the pump casing, the stem being shown provided with circumferential grooves I33 to provide circular air pockets which serve as seals to prevent leakage of liquid fuel from the chamber III. The outer end of the stem I3I is provided with means for rotating it, as for example, a pinion I34 which is fixed thereon and meshes with a gear segment I35 which is pivoted on a screw I36 secured in the pump casing and adapted to be connected to a suitable throttle control member. A spring I34 is preferably interposed between the pinion I34 and the bushing I32 to maintain a fluid-tight fit between the tapered stem I3I and its correspondingly tapered bushing I32, and a spring I31 may be interposed between the segment I35 and the pump casing, this spring serving to return the cam I21 to its normal closed throttle position.

As previously stated, the number of cam projections I28 provided on the cam I21 may be varied according to the number of pump units employed and the number of engine cylinders to be supplied thereby with fuel. For example, in the present instance, in which the pump embodies four pump units spaced apart through angles of 90 degrees around the central shaft 31, two cam projections I28 spaced apart through an angle of 135 degrees will be employed for an eight cylinder engine, such cam projections being timed to correspond with the timing of the cam projections 5| which actuate the pump plungers, as indicated in Fig. 23, but by employing two diametrically opposite pump units and two cam projections I28 and two cam projections 5I each spaced apart through an angle of 90 degrees, the fuel can be injected at proper intervals to a four cylinder engine, and by employing a. cam 50 provided with three cam projections 5| spaced apart through angles of 120 degrees, and a cam I21 having three cam projections I 28 spaced apart through angles of 120 degrees, a pump having two diametrically opposite pump units will be suificient for a six cylinder engine, and a pump having four pump units spaced apart through angles of 90 degrees around the central shaft, will be sufficient for a twelve cylinder engine.

The operation, in the embodiment of the invention disclosed in Figs 16 to 23 inclusive, is as follows: Assuming that liquid fuel is supplied to the chamber I II from a tank or other suitable source through pipe H2 and passage H3 and that the shaft 31 is driven from the engine in appropriately timed relation therewith, liquid fuel will be drawn into the upper end of each pump cylinder, during the down-stroke of its respective plunger 5*, through the respective valve M by the unseating of this valve, and through As a cam projection i on the cam 50* lifts the tappet M of each pump plunger, the latter is forced upwardly on its working stroke, and simultaneously therewith, the tapept I20 above the valve I I0 for such plunger will be depressed by a cam projection I28 on the cam I21 acting on the pin I25 of the tappet, thereby opening the valve H0 and permitting fuel drawn into the respective pump unit to flow back into the supply chamber III and thus bypassed. The amount of fuel thus by-passed de- 'pends upon the adjustment of the disk I22 by the gear I 23 and its controlling means. As soon as the cam projection I28 passes off the pin I25, the tappet is free to rise under the action of the spring N4 of the valve IIO, thereby permitting closing of this valve. By-passing of the fuel from the pump unit is then terminated, and the remaining upward or working stroke of the pump plunger is effective to eject a metered amount of fuel into the engine cylinder. The fuel from the pump units is distributed to the appropriate cylinders by the rotating valve 3|, the fuel from the diiferent pump units being conducted by the radial passages 25 to the central passage 25 whence it flows through central passages 24* and 34 and radial passage 36 to a port 35 in the valve 3|, the rotation of this valve bringing this port into communication successively with the ports 28 which communicate with the pipes 30 which are connected to the fuel injectors in the respective engine cylinders.

The pump shown in Figs. 16 to 23 inclusive may be utilized to drive the conventional form of ignition timer and distributor I00 for the engine, the shaft 31 having a bevel gear I0 I fixed thereon and meshing with a, similar bevel gear I02 fixed on the shaft of the distributor, as in the embodiment shown in Fig. 1.

The present invention provides means for efiectively lubricating the pump plungers, especially when a fuel lighter than the heavier grades of fuel oil is used. Fig. 24 shows a lubricating system for a pump constructed as shown in Figs. 1 to 14 inclusive, the cap I3 having a passage I40 therein connected to receive a suitable grade of lubricating oil from a suitable reservoir, pump and filters through a pipe I M. The oil intro duced into the passage I40 is conducted to a circular groove I42 formed in the under-side of tlte cap I3, and the oil flows from this groove into passages I43 which lead to the respective pump units, the oil filling chambers I44 surrounding each pump cylinder 2. From each chamber, passages I45 lead to the respective plunger 5 and through which the oil flows to the plungers and fills the circumferential grooves 5, thus forming seals between the plunger and its cylinder and also lubricating the plunger and cylinders. The surplus lubricating oil introduced into the distributing groove I4I and which is under pressure, is returned to the reservoir or source of supply through an outlet passage I46 which leads from said groove to an oil return pipe I41. A similar lubricating system for the pump shown in Figs. 16 to 23 inclusive is shown in Fig. 25, with the exception that the lubricating oil entering through the pipe I4I groove I42 and passage I43 enters the passages I45 in the pump cylinders directly,

the surplus oil being returned to the oil reservoir as in Fig. 24.

The present invention provides a multiple unit fuel injecting pump in combination with a distributing valve which enables fuel to be injected into engine cylinders which are of a greater number than the pump units used, thereby sim lifying and reducing the cost of manufacture of the pump, and providing a compact unitary structure which may be accommodated in relatively small space, which is a desideratum particularly in engines for aircraft.

By grouping the pump units in circumferentially spaced relation around a central actuating shaft, the fuel distributing valve and pump actuating cam may be conveniently operated from such shaft, and these parts will be maintained in proper timed relation. Thi concentric relationship of the pump units, distributor valve and actuating cam also enables the pump to be built of a standardized general structure, and to be adapted for the injection of fuel for engines having different numbers of cylindersby equipping the pump with a cap having an appropriate number of fuel distributing ports and passages, and cams having appropriate number and arrangement of cam projections thereon.

I claim as my invention:

1. A fuel injecting pump comprising a group of pump units, a cam mounted concentrically of said units and having portions thereon spaced angularly to actuate the units successively, and a fuel distributing valve mounted coaxially with the cam and connected to receive fuel from the pump units and having outlets of a number which is a multiple of the number of pump units.

2. A fuel injecting pump comprising a group o Dump units, a shaft mounted concentrically of said units, a cam fixed to said shaft for rotation therewith and having projections thereon spaced angularly to cooperate in succession with said units for actuating them at successive intervals, and a valve fixed to said shaft for rotation therewith and embodying means for receiving fuel from the pump units and for distributing it successively to a plurality of outlets 3. A fuel pump comprising a casing, a group of pump units embodying reciprocatory plungers mounted in the casing, a shaft mounted in the casing parallel to the plungers, a cam fixed on the shaft to rotate therewith and having projections thereon spaced angularly to cooperate in succession with the plungers to actuate them successively, and a distributor valve fixed on the shaft to rotate therewith and connected to receive fuel from the pump units and having discharge ports of a number which is a multiple of the num ber of pump units and a distributing port cooperative with said discharge ports in synchronism with the actuations of the plungers by the cam projections for discharging the fuel successively to a plurality of outlets.

4. A fuel injecting pump for internal combustion engines, comprising a casing, a group of pump units in the casing, a shaft mounted in the casing centrally of the group of pump units, a cam on said shaft having a plurality of projections thereon spaced angularly to cooperate in succession with the pump units for actuating them at successive intervals, a distributing valve on said shaft having a distributing part connected to the pump units to receive fuel therefrom, and means fixed on the casing and having discharge ports which register with said distributing port synchronously with the actuations of the pump units by the cam projections, and having passages lead ing from said discharge ports for distributing fuel to the respective cylinders of the engine.

5. A fuel injecting pump for internal combustion engines, comprising a casing, a group of pump units in the casing, a shaft mounted in the casing, a cam on said shaft having a plurality of portions spaced angularly thereon to cooperate in successsion with the pump units for actuating them, means providing a common outlet from the pump units, a distributing valve rotatable by said shaft and having a port arranged to receive fuel from said common outlet and having a fuel distributing port, and means on the casing having a series of discharge ports of a number which is a multiple 12 of the number of pump units and with which the distributing port in the distributing valve communicates synchronously with the actuations of the pump units, and having passages leading from said series of ports for distributing fuel to the respective cylinders of theengine.

6.-A fuel injecting pump for internal combustion engines, comprising a casing, a group of pump units in the casing having reciprocatory plungers, tappets for actuating the plungers, a shaft mounted in the casing, a cam on said shaft having a plurality of actuating portions spaced angularly to cooperate in succession with the tappets for operating said plungers, a distributing valve rotatable by said shaft and having fuel receiving and distributing ports, and means on the casing having a series of ports to receive fuel from the distributing port of said valve synchronously with the actuations of said plungers and having passages leading from said series of ports for distributing fuel to the respective cylinders of the engine.

7. A fuel injecting pump for internal combustion engines, comprising a casing, a group of pump units mounted in the casing, a shaft mounted rotatably in the casing, a cam fixed to said shaft and having a plurality of cam projections thereon spaced angularly to cooperate in succession with the pump units for actuating them at successive intervals, a distributing valve rotatable by said shaft, means on the casing for conducting fuel from the pump units to said valve, means for regulating simultaneously the amount of fuel delivered by the pump units to the distributing valve, and means on the casing for receiving fuel from the distributing valve synchronously with the actuations of the pump units and directing it to the respective cylinders of the engine.

8. A fuel injecting pump for internal combustion engines, comprising a group of pump units, a single distributing valve connected to receive fuel from said units and operative to distribute the fuel to the cylinders of the engine, and a cam having actuating projections thereon for said units, the number of said projections being coordinated with the number of pump units and the number of engine cylinders to which the fuel is distributed by said valve.

9. A fuel injecting pump according to claim 8, wherein said cam projections are of a number and arrangement to produce a number of operations of the pump units which is a multiple of the number of said units.

JOSEPH ANTHONY CIVITARESE.

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

UNITED STATES PATENTS Number Name Date 1,631,185 Anibal June 7, 1927 1,807,650 Chryst et al June 2, 1931 2,050,392 Starr Aug. 11, 1936 2142.086 Alden Jan. 3,1939 2,280,875 Wahlmark Apr. 28, 1942 1,966,911 Stephan July 17, 1934 2,243,995 Alden June 3, 1941 2,255,203 Wiegand Sept. 9, 1941 1603.228 Woerner Oct. 12, 1926 1,971,601 Dilg Aug. 28, 1934 2,060,076 High Nov. 10, 1936 2,160,735 Hoffer May 30, 1939

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