US3323506A

US3323506A - Fuel injection pumps having a rotating distributing valve

Info

Publication number: US3323506A
Application number: US418409A
Authority: US
Inventors: Pigeroulet Jean; Tissot Raymond
Original assignee: Sigma
Current assignee: Sigma; Industrielle Generale de Mecanique Appliquee SIGMA SA
Priority date: 1963-12-19
Filing date: 1964-12-15
Publication date: 1967-06-06
Anticipated expiration: 1984-06-06
Also published as: DE1303637C2; US3323505A; GB1080819A; CH416217A; DE1303637B; CH414261A; FR1387296A; ES307259A1; OA00876A; GB1080818A; BE656525A

Description

June 1967 J. PIGEROULET ETAL. 3,323,506

FUEL INJECTION PUMPS HAVING A ROTATING DISTRIBUTING VALVE Filed Dec. 15, 1964 2 Sheets-Sheet 1 ATTORNY; I

June 1967 J. PIGEROULET ETAL. 3,323,506 v FUEL INJECTION PUMPS HAVING A ROTATING DISTRIBUTING VALVE Filed Deb. 15, 1964 2 Sheets-Sheet a United States Patent 3,323,506 FUEL INJECTIDN PUMPS HAVING A ROTATING DISTRIBUTING VALVE Jean Pigerouiet, Villeurbanne, and Raymond Tissot, Lyon, France, assignors to Societe Industrielle Generale de Mecanique Appliquee S.I.G.M.A., Paris, France Filed Dec. 15, 1964, Ser. No. 418,409

priority, application France, Dec. 19, 1963,

957,848 2 Claims. (Cl. 123-439) The present invention relates to a fuel injection pump for a multicylinder internal combustion engine, said pump comprising a fixed body and, inside said fixed body a rotating distributing valve driven by a shaft itself driven by the engine and substantially coaxial with said distributing valve, such a pump further comprising at least a pump piston reciprocable, in a bore provided in one of the two elements constituted by the fixed body and the driving shaft, under the action of a cam carried by the other of said two elements, the fixed body being provided with distribution conduits loading to the engine injectors and cooperating with distribution passages carried by the rotating distributing valve and adapted to communicate with said bore. The invention is more especially, but not exclusively, concerned with pumps of this type wherein the distributing valve is arranged in such manner as to reduce the rate of delivery of the pump when said rotary valve is given a translatory movement and whereina centrifugal regulating device responsive to the speed of revolution of the engine is adapted to control this distributing valve, with respect to its driving shaft, first in rotaticn (variation of the advance to injection) then in translation (variation of the rate of injection) in response to variations of the speed of the internal combustion engine.

The object of the present invention is to provide a pump of this kind which is :better adapted to meet the requirements of practice than those existing at the present time, concerning the construction of the joint interposed between the internal combustion driving shaft and the distributing valve of the pump.

According to the present invention, the driving part of said joint consists of a sleeve, having some freedom in rotation about a first axis perpendicular to the axis of symmetry of said sleeve and provided, on the inside thereof, with fingers in line with a second axis parallel to the first one and, the distributing valve comprises a portion engaged with some radial play inside the above mentioned sleeve and provided with two helical grooves in which said fingers are engaged, a removable abutment eccentrically mounted with respect to the first axis being advantageously provided inside said sleeve to cooperate with the distributing valve so that the end of the advance movement of the distributing valve can be adjusted by rotation of said abutment about said last mentioned axis.

A preferred embodiment of the present 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 sectional partial view on the line 11-11 of FIG. 1;

FIG. 3 is a cross sectional view on the line III-III of FIG. 1;

FIG. 4 is a sectional view on the line IVIV of FIG. 1.

The fuel injection pu-mp illustrated by the drawings comprises a fixed body 1, preferably made of two coaxial pieces 1a 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.

Claims The opposed pump pistons 5, only one of which is illustrated by the drawings (FIG. 2 thereof), 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 through conduits 8 provided in body 1. Annular cam 7, carried by a discshaped portion 4a integral with driving shaft 4, gives pistons 5 their reciprocating radial movements in cylinders 6 through rollers 9 and push-pieces 10, against the action of return springs 11. Cam 7 is journalled, through a bearing 12, in a casing 13 through the end wall of which shaft 4 extends, with the interposition of packing means 14, said end wall carrying a thrust ball bearing 15 for shaft 4.

In order to feed fuel to cylinders 6, there is provided in casing 13 a feed pump 16 the suction of which communicates with an inlet connection 17. The delivery of this pump 16 communicates through a pipe 13 with a connection 20 adapted in a removable manner to casing 13. This connection is in permanent communication, through a conduit 21 and an annular groove 22 provided in body 1, with equidistant radial holes 23, the number of which is equal to the number of the internal combustion engine cylinders, which holes 23 open into bore 3 opposite a first longitudinal groove (not visible on the drawings) provided in distributing valve 2. This first longitudinal groove opens into a peripheral annular groove 24 provided in distri- Ibuting valve 2 and in permanent communication with pump cylinders 6.

The delivery circuit from said pump cylinders 6 comprises a second longitudinal groove 25 starting from annular groove 24 and leading to delivery passages 8.

It will be understood that fuel injection begins when a hole 23 ceases to be in communication with the second longitudinal groove 25 and that it is cut otf just when the next hole 23 is placed in communication with the first longtiudinal groove.

There is provided a regulating device capable of varying the angular and longitudinal positions of distributing valve 2 with respect to driving shaft 4.

Variation of the angular position of said 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 longitudinal grooves 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 longitudinal grooves are provided with inclined portions, such as 25a, oblique in opposed directions with respect 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 50 capable of sliding without rotating with respect to shaft 4, against the action of a spring 27, while imparting a helical movement to distributing valve 2 through means which Will be hereinafter described. This member 50 is subjected, on the one hand, to the action of said force, and on the other hand, in the opposed direction, to the action of return means adjustable through a forked lever 35.

The regulating device comprises two masses 28 pivoted about two respective axes 29 carried by a projection 4b of shaft 4, each of said masses 28 carrying an arm 30 (FIG. 4), which will be hereinafter referred to, and which serves to produce, through a spindle 51, a longitudinal 3 movement of member 50 serving to control distributing valve 2, against the action of spring 27.

With such a regulating device the angular position of distributing valve 2 with respect to shaft 4 will depend upon the force exerted by masses 23, this force depending itself upon the speed of revolution of the internal combustion engine. Furthermore, the axial position of distributing valve 2 with respect to shaft 4 will depend not only on said force, but also on the position of lever 35.

Preferably, as shown, the return means above referred to consists of a set of springs 33 the end of which opposed to that connected to distributing valve 2 bears upon a cup shaped member 34 movable in response to the movements of the throttle valve of the internal combustion engine, for instance by the provision of forked lever 45 fixed on the spindle 36 of the throttle valve. As for the other end of this set of springs 33, it acts upon distributing valve 2 through a resilient plate 37 carried by a lever 38 pivoted about an axis 39 and interposed between distributing valve 2 and the set of springs 37.

Such a pump works as follows:

When shaft 4 revolves together with cam 7, pistons are alternately pushed outwardly (suction) under the action of springs 11 and inwardly (delivery) when rollers 9 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 the longitudinal grooves of distributing valve 2 and said fuel comes to fill up the volumes resulting from the outward movements of pistons 5 in cylinders 6. During the delivery periods, fuel is delivered into annular groove 24 and the longitudinal grooves of the distributing valve. As long as one of the holes 23 is cleared by longitudinal groove 25, fuel is discharged through this hole 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 this hole by its inclined groove a, the fuel delivered by pistons 5 passes through groove 25 and through that of passages 8 which is located opposite this last mentioned groove and thus reaches the corresponding engine injector. Thus injection takes place until the other longitudinal groove of distributing valve 2, the inclined portion of which is inclined in a direction opposed to that of inclined portion 25a; clears the next hole 23. Therefore the inclined portions related to the two longitudinal grooves of the distributing valve 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 rate of injection of the pump.

Shaft 4 is provided with a coaxial cylindrical recess 40 in which a sleeve is movably fitted through its partly spherical end portion 50a the external diameter of which is equal to the diameter of said cylindrical recess 4c. The remainder of said sleeve 40 has a diameter substantially smaller than that of said cylindrical recess 40, so that sleeve 50 is guided with respect to shaft 4 with a small rotational play about the center of its spherical portion 50a. A spindle 51 extending in a direction perpendicular to shaft 4 is journalled in the projection 4b of shaft 4.

The joint between distributing valve 2 and shaft 4 comprises sleeve 50, which carries fingers 52 (FIG. 3), parallel to spindle 51 and engaged with some radial play in two helical grooves 53 provided in the end portion 2b of distributing valve 2, which end portion 2b is of a diameter substantially smaller than the inner diameter of sleeve 50.

On the other hand, spindle 51, extending through sleeve 50, carries, coaxially mounted thereon, two rollers (FIG. 4) slidable in two slots 54 provided in the wall of shaft portion 41), said slots 54 being parallel to the axis of shaft 4. The outer ends of rollers 55 are engaged in grooves 56 provided in the above mentioned arms 30 rigid with the masses 28 of the regulating device, said grooves 56 being transverse to the direction of shaft 4.

Spring 27 is disposed between sleeve 50 and distributing valve 2, about the portion 2]) thereof.

Advantageously, as shown, the joint further comprises a piece 57 forming an abutment for distributing valve 2. This abutment piece 57, slipped on spindle 51, is disposed inside sleeve 50 coaxially therewith so as to cooperate with the free end of the portion 2b of distributing valve 2. Abutment piece 57 can be mounted on removable spindle 51 in either of two opposed positions about the axis thereof so that the active face of said abutment piece 57 is either at distance a or at distance b from the periphery of spindle 51.

The operation of such a joint is as follows:

The driving torque is transmitted from shaft 4 to distributing valve 2 through spindle 51 and fingers 52, spindle 51 further transmitting to sleeve 50 the movements of the arms 30 of the regulating device. These movements, as above explained, produce first a relative rotation of distributing valve 2, by displacement of fingers 52 in helical grooves 53 with a compression of spring 27, then a translatory displacement of distributing valve 2 by contact of abutment 57 with the end portion 2b of distributing valve 2. If shaft 4 and distributing valve 2 are not in line with each other, this causes sleeve 50 to rotate periodically about the center of its partly spherical portion 50a and fingers 52 to have radial displacements, also periodically, in helical grooves 53. In order to adjust the advance stroke, it is possible either to pivot abutment 57 through about spindle 51 or to substitute for an abutment 57 having given dimensions a and b, another abutment having different respective dimensions.

In a general manner, while the above description discloses what is deemed to be a practical and eflicient embodiment of the present invention, said invention is not limited thereto as there might be changes made in the arrangement, disposition and form of the parts without departing from the principle of the invention as comprehended within the scope of the appended claims.

What we claim is:

1. For use in connection with an internal combustion engine, a fuel injection pump for said engine which comprises, in combination,

a fixed body,

a driving shaft operative by said internal combustion engine and rotatable in said body about an axis,

one of the two above mentioned parts being provided wit-h at least one bore radial with respect to said axis,

a piston slidable in said bore,

a cam rigid with the other of said two first mentioned part operatively connected with said piston for controlling the reciprocating movement thereof in response to the rotation of said two parts with respect to each other,

a distributing valve rotatable in said body and substantially coaxial with said shaft,

said distributing valve being provided with distribution passages adapted to communicate with said bore,

said fixed body being provided with fuel distributing conduits adapted to communicate with said distribution passages,

said shaft being provided with a cylindrical recess coaxial therewith,

a driving sleeve of a diameter smaller than that of said cylindrical recess pivoted to said shaft about a transverse axis perpendicular to the axis of said shaft, said sleeve surrounding an end portion of said distributing valve with some clearance, the external wall of said sleeve comprising a spherical portion having its center at the intersection of said transverse axis and said shaft axis, said spherical portion being of a radius just equal to the diameter of said cylindrical recess, and

3,323,506 5 6 two radial fingers rigid With said sleeve, extending being adapted to cooperate through one or the other of rearwardly with respect the eto, parallel t id its end faces With said end of said distributing valve. transverse axis,

said distributing valve end portion being provided with References cued tWo helical grooves and said fingers slidably engag- 5 UNITED STATES PATENTS ing said helical grooves. 3,062,027 11/1962 Pigeroulet 2. A pump according to claim 1 further comprising a reversible cylindrical abutment piece fitting in said MARK NEWMAN P r 1mm) Examiner Sleeve and slipped on said transverse axis, said abutment m LAURENCE M. GOODRIDGE, Examiner.

Claims

1. FOR USE IN CONNECTION WITH AN INTERNAL COMBUSTION ENGINE, A FUEL INJECTION PUMP FOR SAID ENGINE WHICH COMPRISES, IN COMBINATION, A FIXED BODY, A DRIVING SHAFT OPERATIVE BY SAID INTERNAL COMBUSTION ENGINE AND ROTATABLE IN SAID BODY ABOUT AN AXIS, ONE OF THE TWO ABOVE MENTIONED PARTS BEING PROVIDED WITH AT LEAST ONE BORE RADIAL WITH RESPECT TO SAID AXIS, A PISTON SLIDABLE IN SAID BORE, A CAM RIGID WITH THE OTHER OF SAID TWO FIRST MENTIONED PART OPERATIVELY CONNECTED WITH SAID PISTON FOR CONTROLLING THE RECIPROCATING MOVEMENT THEREOF IN RESPONSE TO THE ROTATION OF SAID TWO PARTS WITH RESPECT TO EACH OTHER, A DISTRIBUTING VALVE ROTATABLE IN SAID BODY AND SUBSTANTIALLY COAXIAL WITH SAID SHAFT, SAID DISTRIBUTING VALVE BEING PROVIDED WITH DISTRIBUTION PASSAGES ADAPTED TO COMMUNICATE WITH SAID BORE, SAID FIXED BODY BEING PROVIDED WITH FUEL DISTRIBUTING CONDUITS ADAPTED TO COMMUNICATE WITH SAID DISTRIBUTION PASSAGES, SAID SHAFT BEING PROVIDED WITH A CYLINDRICAL RECESS COAXIAL THEREWITH, A DRIVING SLEEVE OF A DIAMETER SMALLER THAN THAT OF SAID CYLINDRICAL RECESS PIVOTED TO SAID SHAFT ABOUT A TRANSVERSE AXIS PERPENDICULAR TO THE AXIS OF SAID SHAFT, SAID SLEEVE SURROUNDING AN END PORTION OF SAID DISTRIBUTING VALVE WITH SOME CLEARANCE, THE EXTERNAL WALL OF SAID SLEEVE COMPRISING A SPHERICAL PORTION HAVING ITS CENTER AT THE INTERSECTION OF SAID TRANSVERSE AXIS AND SAID SHAFT AXIS, SAID SPHERICAL PORTION BEING OF A RADIUS JUST EQUAL TO THE DIAMETER OF SAID CYLINDRICAL RECESS, AND TWO RADIAL FINGERS RIGID WITH SAID SLEEVE, EXTENDING REARWARDLY WITH RESPECT THERETO, PARALLEL TO SAID TRANSVERSE AXIS, SAID DISTRIBUTING VALVE END PORTION BEING PROVIDED WITH TWO HELICAL GROOVES AND SAID FINGERS SLIDABLY ENGAGING SAID HELICAL GROOVES.