US3330265A - Fuel injection pumps for internal combustion engines - Google Patents

Description

y 1967 J. R. GIRAUDON ETAL 3,330,265

FUEL INJECTION PUMPS FOR INTERNAL COMBUSTION ENGINES- Filed NOV. 30, 1964 2 Sheets-Sheet 1 BYM n y- ATTORNEY July 11, 1967 J. R- GlRAUDON ETAL FUEL INJECTION PUMPS FOR INTERNAL COMBUSTION ENGINES Filed NOV. 30, 1964 2 Sheets-Sheet 2 V am ATTORNEY United States Patent 3,330,265 FUEL INJECTION PUMPS FOR INTERNAL COMBUSTION ENGINES Jean Ren Giraudon, Paris, and Henri Bordei-Mathiolon, Lyon, France, assignors to Societe Industrielle Generale de Mecanique Appliquee S.I.G.M.A., Paris, France Filed Nov. 30, 1964, Ser. No. 414,643 Claims priority, application France, Dec. 4, 1963, 956,059 2 Claims. (Cl. 123-140) The present invention relates to internal combustion engine fuel injection pumps which comprises, in combination, a fixed body, a rotating distributing valve driven in rotation about its axis in said fixed body by a shaft coaxal therewith, said shaft being itself driven by the internal combustion engine fed with fuel by the pump (said distributing valve being possible slidable longitudinally for regulation purposes), at least one pump piston slida'ble in a transverse cylindrical housing provided in one of the two elements consisting of the fixed body and the rotating valve, under the action of an annular cam driven in rotation by the other of said two elements, the fixed body being provided with delivery conduits Which lead to the engine feed injectors and which cooperate with distributing passages provided in the rotating valve and adapted to communicate with said transverse cylindrical housing, the whole being housed in a closed casing through which said shaft extends.

The invention is more especially concerned with the case where the transverse cylindrical housing for the piston is provided in the fixed body and the annular cam is driven in rotation together with the distributing valve.

The chief object of the present invention is to provide a pump of this kind which is better adapted to meet the requirements of practice, in particular concerning lubrication of the pump.

According to the present invention, the fuel circulation system is made separate from the remainder of the inside of the casing, preferably by disposing the portion of the distributing valve which includes the distributing passages and opposite which opens said transverse cylindrical housing in a continuous longitudinal bore provided in the above mentioned body and including two annular end grooves capable of collecting possible leaks of the fuel between the rotating distributing valve and the wall of said longitudinal bore, and means are provided for maintaining a lubricant in said remainder of the inside of the casing, for lubricating the movable parts therein, said last mentioned means advantageously comprising a lubricant circulation pump coupled with a primary fuel feed pump made fluidtight with respect to the remainder of the casing.

According to another feature of the invention the casing is provided with an orifice fitted with a removable connection serving to the inflow of fuel and said orifice is arranged in such manner that, after removal of said connection, it is possible to introduce thereinto a rod extending in a given direction so as to come into contact with the annular cam, said cam being provided with a notch adapted to accommodate said rod, whereby, after the engine shaft has been brought into a given position, it is possible to connect said shaft with the shaft of the pump with the proper angular setting.

Preferred embodiments of our invention will be hereinafter described with reference to the appended drawings, given merely by way of example, and in which:

FIG. 1 is an axial sectional view of a fuel injection pump made according to the present invention;

FIG. 2 is a cross sectional view on the line II-II of FIG. 1;

FIG. 3 is a partial axial sectional view in a different from the section plane of FIG. 1;

radial plane 3,339,265 Patented July 11, 1967 FIG. 4 is a view similar to a portion of FIG. 1 and relative to a modification;

FIG. 5 is an axial sectional view cam of FIG. 4 is controlled; and

FIG. 6 is a sectional view on the line VIVI of FIG. 5.

The fuel injection pump illustrated by the drawings comprises a fixed body 1, preferably made of two coaxial pieces 10 and 1b, and a distributing valve 2 rotating in a cylindrical bore 3 provided in body 1, said valve 2 being driven in rotation by a shaft 4 itself driven by the internal combustion engine (not shown by the drawings) fed with fuel by the pump.

Two opposed pump pistons 5, only one of which is visible (FIG. 3), are slidable, in respective cylinders 6 substantially perpendicular to the common axis of distributing valve 2 and shaft 4, under the action of an annular cam 7 including as many inward projections as the internal combustion engine comprises cylinders to be fed successively with fuel.

Cylinders 6 are placed in communication with the injectors of the internal combustion engine, respectively, through conduits 8 provided in fixed body 1, with the interposition of connections 9 provided with check valves 10 illustrating how the Annular cam 7, carried by a disc-shaped portion 4a integral with driving shaft 4, gives pistons 5 their reciprocating radial movements in cylinders 6 through rollers 11 and push-pieces 12 against the action of return springs 13. Cam 7 is mounted rotatable, through a bearing 14, in a casing 15 through the end of which shaft 4 extends with the interposition of packing means 16.

In order to feed fuel to cylinders 6, we provide, in casing 15, a feed pump 17 the suction of which communicates with an inlet connection 18. The delivery of this pump 17 communicates through a pipe 19 with a connection 20 opening into the inlet 21 of the fuel injec tion pump. Connection 20 is in permanent communication, through an annular groove 22 provided in body element 1b, with equidistant radial holes 23 the number of which is equal to the number of cylinders of the internal combustion engine to be fed with fuel by the pump. These radial holes open into bore 3 opposite a longitudinal groove 24 provided in rotating distributing valve 2. This longitudinal groove 24 opens into a peripheral annular groove 25 provide in distributing valve 2 and in perma net communication with pump cylinders 6.

The delivery circuit from said pump cylinders 6 comprises a second longitudinal groove 26 starting from annular groove 25 and leading to delivery passages 8.

It will be understood that fuel injection begins when a hole 23 ceases to be in communication with longitudinal groove 26 and that it is cut off just when the next hole 23 is placed in communication with longitudinal groove 24.

We provide a regulating device capable of varying the angular and longitudinal position of rotating distributing valve 2 with respect to driving shaft 4.

Variation of the angular position of said rotating distributing valve 2 with respect to shaft 4 offsets in the cycle of operation the period for which no radial hole 23 communicates with both of the two grooves 24 and 26 of distributing valve 2, that is to say varies the advance to injection, whereas variation of the longitudinal position of distributing valve 2 varies the flow rate of the pump per revolution if said grooves 24 and 26 are provided with inclined portions 24a and 26a oblique to the axis of distributing valve 2 and located opposite radial holes 23.

For this purpose, there is provided a regulating device capable of exerting an axial force variable in the same manner as the speed of rotation of shaft 4 upon a member 27 capable of sliding without rotating with respect to shaft 4, against the action of a spring 28, owing to the clined portion 24a, the next hole 23.

provision of a pin 29 rigid with member 27 and movable in a helical slot of distributing valve 2, this member being subjected, on the one hand, to the action of said force and, on the other hand, in the opposed direction, to the action of resilient return means which are determined in such manner as to yield after spring 28.

The regulatingdevice comprises two masses 3%} pivoted about two respective axes 31 journalled in a flange 32 of shaft 4, each of said masses 30 being capable of longitudinally displacing a push-piece 33 capable of exerting an axial thrust, against the action of spring 28, upon member 27, which serves to control distributing valve 2.

With such a regulating device the axial and angular positions of distributing valve 2 with respect to shaft 4 will depend upon the position of masses 30, which position itself depends upon the speed of the internal combustion engine, increase of said speed tending to reduce the flow rate of fuel.

' Preferably, as shown, the return means consists of a set of springs 24 the end of which opposed to that connected to distributing valve 2 bears upon a cup-shaped member 35 movable in response to the movements of the throttle Valve of the internal combustion engine, for instance by the provision of a forked lever 36 fixed on the spindle 37 of said throttle valve. As for the other end of this set of springs it acts upon said distributing valve 2 not directly but through a resilient plate 38 carried by a lever 39 pivoted about an axis 40 and interposed between distributing valve 2and the set of springs 34.

Such a pump works as follows:

When shaft 4 revolves together with its cam 7, pistons are alternately pushed outwardly (suction) under the action of springs 13 and inwardly (delivery) when'the rollers associated with said pistons run along the bosses of cam 7. During the suction periods, the fuel under pressure in annular groove 22 passes through holes 23, located opposite grooves 24 and 26, and comes to fill up the volumes resulting from the outward movements of pistons 5 in cylinder 6. During the delivery periods, fuel is delivered into annular groove 25 and longitudinal grooves 24 and 25. As long as one of the holes 23 is cleared by groove 26, fuel is discharged through said hole 23 into annular groove 22 and there is no injection. As soon as distributing valve 2, which rotates at the same speed as cam 7, has covered said hole 23 by its inclined groove 26a, the fuel delivered by pistons 5 passes through groove 26 and through that of passages 8 which is located opposite this lastrmentioned groove and thus reaches the corresponding engine injector through check valve and connection 9 leading therefrom. Thus injection takes place until longitudinal groove 24 clears, through its in- Therefore inclined portions 26a and 24a determine the beginning and the end of injection, respectively, the regulating device determining the beginning of injection in every cycle of the pump and the flow rate of the pump.

Up to the present time, lubrication of the pump was ensured by the fuel itself, which generally filled casing 15. This prevented the utilization of light fuels, which have no lubrifying properties (forinstance gasoline).

One of the objects of the invention is to permit of using such pump with any liquid fuel whatever.

For this purpose, according to one of the features of the invention, the fuel circuit is separated from the remainder of the inside of casing and means are provided for maintaining a lubricant in said remainder of the inside of casing 15. 7

As shown by the drawings, considering the portion of distributing valve 2 which comprises angular groove and longitudinal grooves 24 and 25 and opposite which cylinders 6, passages 8 and holes 23 open, the bore 3 in which said distributing valve portion is disposed is arranged in such manner as to be continuous inside the pump body (that is to say without direct communication with casing 15) and to comprise two annular end grooves 4 V 41 adapted to collect any possible leaks of fuel at high pressure between distributing valve 2 and the wall of said bore 3. Grooves 41 may be connected through passages 42 with holes 23 and/or with annular groove 22. a As for the means for keeping a lubricant in the portron of the inside of casing 15 which is out of communication with the fuel circuit, said means may include a pump 43 intended to circulate lubricating oil and coupled with primary pump 17. This pump 43 may be of the same type as said primary pump'17 and anyway it is separated therefrom by packing joints 44. The suction of pump 43 is connected to an oil inlet connection 45 in communication with a tank (not shown) and said pump 43 delivers oil into casing 15 through aport 46. A discharge valve 47 maintains a given oil pressure inside the casing, the excess of oil allowed to pass out by this valve returning to said tank. a 7

Due to the fact that, contrary to what occurs in known pumps, the excess of fuel delivered by primary pump 17' cannot be collected in casing 15, we provide a discharge valve 49 (FIG. 2) communicating preferably with groove 22 and capable of returning the excess of fuel to a suitable tank or to connection 18.

It will be understood that the following elements are immersed in the oil permanently maintained in casing 15: centrifugal governor including masses 30, connecting means, such as 27, 29 and 33 between this regulating device and distributing valve 2, springs 34 and connecting means between said springs and distributing valve 2, lever 30 and the like. It is therefore possible to use the pump with non-lubricating fuels.

According to another feature of our invention, orifice 21 is located in such manner that, after removal of connection 20, it is possible to insert a rod 50 (FIG. 5) so that it comes into contact with cam 7, said cam being prgvided with a notch 51 adapted to accommodate said ro When the fuel circuit and the lubricant circuit are separate from each other as above described, orifice 21 advantageously opens opposite a conduit 52 provided in the external portion 112 of body 1 and communicating with groove 22. It then suffices to provide, opposite orifice-21 on the outside of conduit 52, a passage 53 extending through the portion 117 of body 1, this passage 53 having a diameter equal to that of rod 50 and being capable of giving the latter-the above mentioned direction. In normal and 6) first into passage 53, then into notch 51 after ro-.

tation of shaft 4 and cam 7 through an angle determined by hit and miss. After the shaft of the engine has been brought into a reference position the shaft of the engine can then be connected to the shaft of the pump with the proper mutual angular setting. The length of rod 50 is sufficiently great to prevent the fixation of connection 20 by mistake when' this rod is still engaged in orifice 21.

In a general manner, while the above description discloses what are deemed to be practical and efficient embodirnents of the present invention, said invention is not limited thereto as there might be changes made in the arrangement, disposition and form of the part without depart ng from the principle of the present invention as comprehended within the scope of the appended claims,

What we claim is: a

1. A fuel injection system which comprises, in com-. bination, a

a closed casing including two portions, a first one and a second one, a fixed body in the first portion of said casing,

a driving shaft journalled in said body about an axis with at least one cylindrical housing transverse to said axis,

a piston slidable in said housing so as to form therewith a pumping chamber,

a cam carried by the other of said two parts, said cam being operatively connected with said piston for imparting a reciprocating movement thereto in said cylindrical housing in response to rotation of said shaft in said casing so as to produce a given number of pumping reciprocations of said piston during every revolution of said shaft,

said body being provided with a cylindrical bore coaxial with said shaft,

a rotating distributing valve fitting slidably in said bore, said distributing valve being operatively connected with said shaft so as to be driven by it,

a fuel feed conduit,

a plurality of fuel injection connections, the number of said connections being equal to said given number, said body being provided on the one hand with intake conduits each opening at one end into said bore and communicating at the other end with said fuel feed conduit and on the other hand with delivery conduits each opening at one end into said bore and communicating at the other end with one of said fuel injection connections, respectively,

said distributing valve being provided with fuel distributing passage means for placing, during every revolution of said shaft, said pumping chamber in communication with said delivery conduits, successively and cyclically, for respective time intervals and for placing said pumping chamber in communication with said intake conduits during time intervals occurring between said first mentioned time intervals,

said body being provided with a orifice for the inflow of fuel thereinto and with a passage extending from said orifice to a point located opposite said cam, and

a removable connection adapted to be secured to said body for the inflow of fuel thereinto,

said cab being provided with a notch located opposite said passage,

whereby, after removal of said connection, a rod can be introduced through said passage and inserted in said notch for positioning said driving shaft with respect to said rotating distributing valve.

2. A system according to claim 1 wherein said passage is cylindrical and parallel to said bore, further comprising a plug for Stopping said last mentioned passage.

References Cited UNITED STATES PATENTS 2,053,027 9/1936 Franks 123139 2,410,947 11/1946 Johnson 123139 X 2,518,473 8/1950 Hogeman et a1 1032.1 2,779,289 1/1957 Hogeman 103169 2,794,397 6/1957 Burman 123-140 X 2,968,298 1/1961 Meurer 123139 3,091,231 5/1963 Giraudon 123-140 MARK NEWMAN, Primary Examiner. LAURENCE M. GOODRIDGE, Examiner.

Claims (1)

1. A FUEL INJECTION SYSTEM WHICH COMPRISES, IN COMBINATION, A CLOSED CASING INCLUDING TWO PORTIONS, A FIRST ONE AND A SECOND ONE, A FIXED BODY IN THE FIRST PORTION OF SAID CASING, A DRIVING SHAFT JOURNALLED IN SAID BODY ABOUT AN AXIS FIXED WITH RESPECT THERETO, ONE OF THE TWO LAST MENTIONED PARTS BEING PROVIDED WITH AT LEAST ONE CYLINDRICAL HOUSING TRANSVERSE TO SAID AXIS, A PISTON SLIDABLE IN SAID HOUSING SO AS TO FORM THEREWITH A PUMPING CHAMBER, A CAM CARRIED BY THE OTHER OF SAID TWO PARTS, SAID CAM BEING OPERATIVELY CONNECTED WITH SAID PISTON FOR INPARTING A RECIPROCATING MOVEMENT THERETO IN SAID CYLINDRICAL HOUSING IN RESPONSE TO ROTATION OF SAID SHAFT IN SAID CASING SO AS TO PRODUCE A GIVEN NUMBER OF PUMPING RECIPROCATIONS OF SAID PISTON DURING EVERY REVOLUTION OF SAID SHAFT, SAID BODY BEING PROVIDED WITH A CYLINDRICAL BORE COAXIAL WITH SAID SHAFT, A ROTATING DISTRIBUTING VALVE FITTING SLIDABLY IN SAID BORE, SAID DISTRIBUTING VALVE BEING OPERATIVELY CONNECTED WITH SAID SHAFT SO AS TO BE DRIVEN BY IT, A FUEL FEED CONDUIT, A PLURALITY OF FUEL INJECTION CONNECTIONS, THE NUMBER OF SAID CONNECTIONS BEING EQUAL TO SAID GIVEN NUMBER,

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