US3256833A

US3256833A - Fuel injection system for internal combustion engines

Info

Publication number: US3256833A
Application number: US444715A
Authority: US
Inventors: Papst Hermann
Original assignee: Individual
Current assignee: Individual
Priority date: 1961-11-15
Filing date: 1965-04-01
Publication date: 1966-06-21
Anticipated expiration: 1983-06-21
Also published as: GB1003050A; US3186386A; DE1288848B; CH407651A; AT249448B; FR1514908A

Description

- June 21, 1966 H. PAPST 3,256,833

FUEL INJECTION SYSTEM FOR INTERNAL COMBUSTION ENGINES Filed April 1, 1965 Fig-2 F 9- 20 I 6' 1 lnventor: Hermann Papst by MMfi r attorney P 23, 12 Claims. (Cl. 103154) The present application is a continuation-in-part application of the copending application Serial No. 237,634, filed November 14, 1962, and entitled Combined Fuel Injection and Ignition System for Internal Combustion Engines, now United States Letters Patent No. 3,186,386.

The present invention relates to a pump, such as for instance a fuel pump for an internal combustion engine. More specifically, the present invention relates to an arrangement for releasably and fluid tightly connecting a capillary tube leading from the outlet passage of the pump to an injection nozzle communicating with the interior of the combustion chamber of the internal combustion engine.

The parent application of which the present application is a continuation-in-part application discloses a fuel pump and an injection and igniting system having at least one injection nozzle communicating with the outlet passage of the pump through a capillary tube.

From time to time it is necessary to remove the nozzle or nozzles from the cylinder of the internal combustion engine for cleaning the nozzle and the capillary tube or for replacing the same by a new one.

It is an object of the present invention to provide means for easily connecting and disconnecting a capillary tube to the outlet endof a fuel pump of an internal combustion engine or the like.

. It is a further object of the present invention to provide for connecting means of the type mentioned which when connected will establish a fluid tight connection between the capillary tube and the outlet passage of the pump.

. It is an additional object of the present invention to provide for connecting means for the aforementioned purpose which also facilitate when disconnected to remove various parts of the pump from the latter without' disassembling the whole pump.

Finally, it is an object of the present invention to provide for connecting means for the above-mentioned or a similar purpose which are constructed of relatively few and simple parts so that the whole arrangement can be manufactured at very reasonable cost and will stand up properly under extended use.

With these objects in view, the pump of the present invention mainly comprises pump body means, pumping means in the pump body means and having an inlet passage for feeding fluid into the pumping means and an outlet passage for discharging fluid under pressure therefrom, chamber means formed in the body means and being in part defined by a face at which the outlet passage ends, a connecting member removably located in the chamber means and abutting against the face thereof, the connecting member being formed with passage means therethrough communicating at the aforementioned face with the end of the outlet passage, releasable pressure means connected to the body means and engaging the connecting member for pressing the connecting member against said face, and a tube connected at one end thereof to the connecting member and communicating at the aforementioned end with the passage means, the other end of the tube being adapted to be connected to the fuel injection and ignition system of an internal comb-ustion engine or the like.

United States Patent Preferably, the pump body is formed with a stepped bore having an inner small diameter portion and an outer large diameter portion and a shoulder face between the aforementioned portions. The large diameter portion is preferably provided at the outer end thereof with a screw thread and the pump body is also formed with a cutout extending transverse to the axis of the aforementioned bore from the outer surface of the body into the large diameter portion of the bore. The pump means prefer ably comprise cylinder means slidably fitted in the bore portions and -having a shoulder face abutting against the shoulder face of the bore. The cylinder means has an end face in the large diameter portion of the bore and located in the region of the cutout and a coaxial outlet passage ending at the aforementioned end face. The pumping means further comprise a piston reciprocable in the cylinder means and drive means operatively connected to the piston for reciprocating the latter. An inlet passage is also provided extending through the pump body and the cylinder means to communicate with the interior of the latter. The connecting member is prefer ably'flat and has a pair of substantially parallel faces and the connecting member extends through the cutout into the large diameter portion of the bore with one of the aforementioned parallel faces thereof abutting against the end face of the cylinder means. The connecting member is formed with passage means therethrough having an open end at the aforementioned parallel face abutting against the end face of the cylinder means and the passage means are aligned with the outlet passage and communicate therewith. The releasable pressure means are preferably in the form of a pressure screw screwed into the threaded end of the bore'and engaging with one end thereof the other of the aforementioned parallel faces of the connecting member for pressing the first mentioned face thereof against the end face of the cylinder means and pressing thereby also the shoulder face of the cyl-' inder means against the shoulder face of the pump body. A tube, preferably in the form of a capillary tube, is, as mentioned before, connected at one end thereof to the connecting member communicating with the other end of the passage means therethrough, while the other end of the capillary tube is adapted to be connected to the fuel injection and ignition system.

When the pressure screw is tightened, the one face of the flat connecting member will be fluid tightly pressed against the end face of the cylinder means to establish thereby a fluid tight connection between the outlet passage of the cylinder means and the capillary tube. When the pressure screw is loosened, the connecting member may be withdrawn through the open end of the cutout from the pump body so as to disconnect in a very simple manner the capillary tube from the pump. The pressure screw has preferably a diameter greater than that of the cylinder means so that, when the pressure screw is completely screwed out of the threaded end of the bore in the pump body, the cylinder means, slidably fitted in the bore, may also be withdrawn therefrom after the connecting member is withdrawn from the cutout in the manner as mentioned above.

The novel features which are considered as characteristic for the invention are set forth in particular in. the appended claims. The invention itself, however, both as to its construction and its method of operation, together with additional objects and advantages thereof, will be best understood from the following description of specific embodiments when read in connection with the accompanying drawings, in which:

FIG. 1 is a sectioned side view of the pump arrangement according to the present invention;

FIG. 2 is a cross section taken along the line II-II of FIG. 1 and viewed in the direction of the arrows; and

FIG. 3 is a partial sectioned side view similar to FIG. 1 and showing a modified arrangement.

Referring now to the drawing, and more specifically toFIG. 1 of the same, it will be seen that the pump arrangement according to the present invention comprises a pump body 1 having a downwardly extending substantially cylindrical portion 2 formed with a stepped bore 3 extending coaxial with the cylindrical portion 2 through the pump body 1. The stepped bore 3 has an inner small diameter portion 3a and an outer large diameter portion 3b formed at the outer end thereof with a screw thread 30. A shoulder face 3d extending substantially normal to the axis of the bore 3 is formed between the small diameter portion 3a and the large diameter portion 312. The cylindrical portion 2 of the pump body is also formed with a cutout or chamber means 6 having an open end at the outer surface of the cylindrical portion 2 and extending substantially normal to the axis of the bore 3 into the large diameter portion 3b. The cutout 6 has substantially parallel side faces 6a, as best shown in FIG. 2, spaced from each other a distance equal to the diameter of the large diameter portion 3b of the bore so that the cutout blends into the large diameter portion as shown in FIG. 2.

Cylinder means are slidably fitted in the portions of the bore 3 and the cylinder means include a cylinder member 4 having an upper small diameter portion located in the small diameter portion 3a of the bore and a lower portion of larger diameter located in the large diameter portion 3b of the bore.

Inlet passage means 7 are formed in part through the pump body 1 and in part through the cylinder member 4 and communicate with the interior of the latter spaced from the bottom end thereof for feeding fuel from a fuel reservoir, not shown in the drawing, into the interior of the cylinder member 4. The inlet passage '7 preferably comprises a bore 7a extending inclined to the axis of the bore 3 through the pump body 1 and being closed at the upper end thereof by a screw plug or the like, whereas the lower end of the bore 7a communicates with an annular groove 7c about the small diameter portion 3a of the bore 3 and open to the inner surface of the bore. A plurality of radially extending bores 70? of a diameter slightly smaller than the width of the annular groove 70 communicate at the outer ends thereof with groove 7c and at the inner ends thereof with the interior of the cylinder member 4. A bore 7b intersecting the bore 7a is connected at its outer end thereof in a manner not shown in the drawing to the aforementioned fuel reservoir.

The cylinder member 4 is formed at the lower end thereof with an outlet passage 8 ending at the lower end of the cylinder member in a substantially frustoconical valve seat in which a correspondingly shaped valve mernher 9 is located movable between a closed position engaging the valve seat and an open position spaced therefrom. A spring plate 19 abutting with its upper surface thereof against the bottom face of the cylinder member 4 and the valve member 9 resiliently maintains the latter in the closed position thereof while permitting, when its central portion flexes in downward direction, the valve member to move to the open position. The spring plate 10 is formed with openings 10' therethrough permitting fluid to pass through the spring plate when the valve member 9 is in the open position. The spring plate 10 is held on the bottom face of the cylinder member 4, while being permitted to flex in the aforementioned manner, by a retainer and spacer member 11 which has an annular flange portion engaging an outer annular portion of the spring plate 10, and a cylindrical portion extending upwardly from the flange portion and being clamped between the outer surface of the lower portion of the cylindrical member 4 and the inner surface of the large diameter portion 3b of the stepped bore through the pump body 1. The bottom face of the spacer member 11 forms the end face of the cylinder means, and this end face is preferably located slightly below the upper face 612 of the cutout or chamber 6.

A piston 5 is slidably mounted in the bore of the cylinder member 4 with the upper end of the piston projecting beyond the upper end of the cylinder member. Drive means are provided for reciprocating the piston 5 between a pressure stroke and a suction stroke. The drive means include, as schematically shown in FIG. 1, a cam 12 fixedly mounted on a cam shaft 13, which is rotated about its aXis by conventional means not shown in the drawing, and which drives the cam 12 in the direction as indicated by the arrow A. A lever 14, schematically illustrated in FIG. 1, is hingedly mounted at one of the ends thereof at 14a in the pump body 1, while the opposite end 1417 of the lever 14 is formed as a cam follower and engages the peripheral cam surface of the cam 12. A compression spring 15, housed at its upper end in a cavity 16a of a cover 16 connected in any convenient manner to the pump body 1, engages with its lower end the arm 14 between its ends so as to press the cam follower 14b of the arm against the peripheral cam surface so that during rotation of the cam 12 the arm 14 will oscillate about its pivot 14a. A compression spring 17, weaker than the spring 15, is coiled about an upper portion of the piston 5 and engages with opposite ends thereof an upwardly facing shoulder face on the cylinder member 4 and a flange portion 5a on the upper end of the piston 5 to maintain the upper end of the piston in engagement with the bottom face of the lever 14 so that during rotation of the cam 12 the piston 5 will be reciprocated in the bore of the cylinder member 4.

A substantially fiat connecting member 18 having a plane bottom face 18a and a plane top face 18b parallel to the bottom face extends, as shown in FIGS. 1 and 2,

through the cutout 6 into the large diameter portion 3b of A the bore 3 and engages with its top face 18b the bottom face of the spacer member 11. The connecting member 18 is formed with passage means therethrough having a short portion 19a axially aligned with the axis of the cylinder 4 and extending from the top fa-ce 13b of the connecting member into the latter, and a portion 19b extending transverse to the portion 19a from the latter to the outer surface of the connecting member 18. The outer portion of the passage portion 19b has preferably an enlarged diameter and one end of a capillary tube 20 extends into this enlarged diameter portion of the passage 1% and is fluid tightly fixed to the connecting member 18 in any well known manner. The other end of the capillary tube 20 is fixed to a nozzle of a fuel injection and ignition system of an internal combustion engine in a manner as shown in the aforementioned application Serial No. 237,634.

A pressure screw 21 is threadingly engaged with the internal screw thread 30 formed in the bottom end of the enlarged diameter portion 3b of the bore 3, and the screw 21 engages with its upper end the bottom face 18a of the connecting member 18 to press the top face 18b thereof tightly against the bottom face of the spacer member 11 and thereby also the shoulder face of the cylinder member 4 toward the shoulder face 3d of the bore 3. Such pressure will establish a fluid tight connection between the outlet passage 8 of the cylinder member and the passage 1%, 1915 through the connecting member 18 and the capillary tube 20 connected thereto. The screw 21 is formed at its bottom end thereof with a hexagonal recess 21a for engagement with an appropriately shaped wrench so that the screw 21 may be properly tightened and loosened when necessary. The screw 21 forms therefor releasable pressure means connected to the pump body 1 and engaging the connecting member 18 for pressing the connecting member against the end face of the cylinder means. The diameter of the pressure screw 21 and the corresponding bore portion 3c is preferably slightly greater than the outer diameter of the lower end of the cylinder 4 and preferably also slightly greater than the outer diameter of the spacer member 11.

After loosening of the pressure screw 21, the connecting member 18 may be withdrawn through the open end of the cutout 6 to the exterior of the pump body 1 so that the capillary tube 20 may be easily cleaned or be replaced when necessary. When the pressure screw 21 is completely screwed out of the body 1, the cylinder means, that is the cylinder member 4, the spring plate and the spacer member 11, together with the piston 5 and the spring 17 may also .be withdrawn from the pump body 1 without disassembling the pump.

An annular spacer member 22 is preferably sandwiched between the shoulder face 3d of the bore 3 and the corresponding shoulder face of the cylinder member 4. By removing this annular spacer member 22 or by changing the same against one of different thickness, the axial position of :the cylinder member 4 relative to the end positions of the piston 5 at the pressure stroke and the suction stroke thereof, respectively, may be slightly changed to change thereby timing and amount of fuel pumped by the reciprocating piston. This is especially important if the pump is used for supplying fuel to an internal combustion engine having a plurality of cylinders and in which a plurality of pumps as described above are driven from a common shaft 13. Since the diameters of the radial bores 7d are slightly smaller than the height of the annular groove 70, the bores 7d will maintain communication with the groove 70, even if the axial position of the cylinder member 4 is slightly changed.

FIG. 3 shows a slight modification of the arrangment described above in connection with FIGS. land 2 and the only difference between the modification shown in FIG. 3 and that shown in FIG. 1 is that in the modification shown in FIG. 3 the fiat connecting member 18' is in the form of a cylindrical plug having parallel top and bottom faces and a diameter not exceeding the outer diameter of the spacer member. 11. The bottom end of the connecting member 18 shown in FIG. 3 is preferably chamfered. In this case the end face of the cylinder means, that is the bottom face of the spacer member 11, does not have to extend downwardly beyond the upper face 6b of the cutout 6', and the height of the cutout 6 does not have to be greater than the height of the connecting member 18'.

It will be understood that each of the elements described above, or two or more together, may also find a useful application in other types of releasable and fluid tight connection between a fluid pasage and atube differing from the types described above.

While the invention has been illustrated and described as embodied in a'pump with releasable and fluid tight connection of a tube to the outlet passage of the pump, it is not intended to be limited to the details shown, since various modifications and structural changes may be made Without departing in any way from the spirit of the present invention.

Without further analysis, the forgoing will so fully reveal the gist of the present invention that others can by applying current knowledge readily adapt it for various applications without omitting features that, from the standpoint of prior art, fairly constitute essential characteristics of the generic or specific aspects of this invention and, therefore, such adaptations should and are intended to be comprehended within the meaning and range of equivalence of the following claims.

What is claimed as new and desired to be secured by Letters Patent is:

1. In a pump for a fuel injection system of an internal combustion engine or the like, in combination, pump body means; pumping means in said pump body means having an inlet passage for feeding fluid into said pumping means and an outlet passage for discharing fluid under pressure therefrom; chamber means formed in said body means and being in part defined by a face at which said outlet passage ends; a connecting member removably located in said chamber means and abuttingagainst said face thereof, said connecting member being formed with passage means therethrough communicating at said face with said end of said outlet passage; releasable pressure means connected to said body means and engaging said connecting member for pressing said connecting member against said face; and a tube connected at one end thereof to said connecting member and communicating at said one end with said passage means, the other end of said tube being adapted to be connected to the fuel injection system.

2. In a pump for a fuel injection system of an internal combustion engine or the like, in combination, a pump body; cylinder means in said pump body, said cylinder means having a fluid inlet passage for feeding fluid into said cylinder means and an outlet passage for discharging fluid under pressure therefrom, said outlet passage terminating at an end face of said cylinder means; a piston reciprocable in said cylinder means; drive means operatively connected to said piston for reciprocating the same; chamber means formed in said pump body and being in part defined by said end face; a connecting member located in said chamber means and abutting against said end face, said connecting member being formed with passage means therethrough communicating at said end face with said outlet passage; releasable pressure means connected to said pump body and engaging said connecting member for pressing the latter against said end face; and a capillary tube connected at one end thereof to said connecting member and communicating at said one end with said passage means, the other end of said capillary tube being adapted to be connected to the fuel injection system.

3. In a pump for a fuel injection system of an internal combustion engine or the like, in combination, a pump body; cylinder means in said pump body, said cylinder means having a fluid inlet passage for feeding fluid into said cylinder means and an outlet passage for discharging fluid under pressure therefrom, said outlet passage being coaxial with said cylinder means and terminating at an end face of said cylinder means; a piston reciprocable in said cylinder means; drive means operatively connected to said piston for reciprocating the same; chamber means formed in said pump body and being in part defined by said end face, said chamber means extending transverse to the axis of' said cylinder means and having an open end at the outer surface of said pump body;.a substantially flat connecting member located in said chamber means and having an abutting face abutting against said end face, said connecting member being formed with passage means therethrough having one end at said abutting face and communicating at said one end thereof with said outlet passage; releasable pressure means connected to said pump body and engaging said connecting member on a face of the latter opposite said abutting face thereof for pressing the latter against said end face, said connecting member being, when said pressure means are released, withdrawable from said chamber means through said open end thereof; and a capillary tube connected at one end thereof to said connecting member and communicating at said one end with said passage means, the other end of said capillary tube being adapted to be connect-ed to the fuel injection system.

4. In a pump for a fuel injection system of an internal combustion engine or the like, in combination, a pump .body; cylinder means in said pump body, said cylinder -means having a fluid inlet passage for feeding fluid into said cylinder means and an outlet passage for discharging fluid under pressure therefrom, said outlet passage being coaxial with said cylinder means and terminating at an end face of said cylinder means; a piston reciprocable in said cylinder means; drive means operatively connected to said piston for reciprocating the same; chamber means formed in said pump body and being in part defined by said end face, said chamber means extending transverse to the axis of said cylinder means and having an open end at the outer surface of said pump body; a substantially fiat connecting member located in said chamber means and having a pair of substantially parallel faces, one of said parallel faces abutting against said end face, said connecting means being formed with passage means therethrough having an open end at said one face thereof and communicating at said one open end with said outlet passage; releasable pressure means connected to said pump body and engaging said connecting member on the other one of said parallel faces for pressing said one of said parallel faces against said end face, said connecting member being, when said pressure means are released, withdrawable from said chamber means through said open end thereof; and a capillary tube connected at one end thereof to said connecting member and communicating at said one end with said passage means,-the outer end of said capillary tube being adapted to be connected to the fuel injection system.

5. In a pump for a fuel injection system of an internal combustion engine or the like, in combination, a pump body; cylinder means in said pump body, said cylinder means having a fluid inlet passage for feeding fluid into said cylinder means and an outlet passage for discharging fluid under pressure therefrom, said outlet passage being coaxial with said cylinder means and terminating at an end face of said cylinder means; a piston reciprocable in said cylinder means; drive means operatively connected to said piston for reciprocating the same; chamber means formed in said pump body and being in part defined by said end face, said chamber means extending transverse to theaxis of said cylinder means and having an open end at the outer surface of said pump body; a substantially flat connecting member located in said chamber means and having a pair of substantially parallel faces, one of said parallel faces abutting against said end face, said connecting means being formed wit-h passage means therethrough having an open end at said one face thereof and communicating at said one open end with said outlet passage, said pump body being formed with a threaded bore extending aligned with the axis of said cylinder means from a face of said chamber means opposite said end face to the outer surface of said body; apressure screw threaded in said threaded bore and engaging with one end thereof the other one of said parallel faces of said connecting member for pressing said one face there of against said end face of said'cylinder means; and a capillary tube connected at one end thereof to said con necting member and communicating at said one end with said passage means, the other end of said capillary tube being adapted to be connected to the fuel injection system.

6. In a pump as defined in claim 5, wherein the diameter of said threaded bore is greater than the maximum diameter of said cylinder means and wherein said cylinder means is mounted in said pump body in such a manner that after unscrewing said pressure screw from said threaded bore and removal of said connecting member from said chamber means, said cylinder means may be withdrawn through said threaded bore from said pump body.

7. In a pump for a fuel injection system of an internal combustion engine or the like, in combination, a pump body formed with a stepped bore having an inner small diameter portion and an outer large diameter portion and a shoulder face between said portions, said large diameter portion being provided at the outer end thereof with a screw thread, said body being also formed with a cutout extending transverse to the axis of said bore from the outer surface of said body into said large diameter portion of said bore; cylinder means slidably fitted in said portions of said bore and having a shoulder face abutting against said shoulder face of said bore, said cylinder means having an end face in said large diameter portion of said bore and located in the region of said cutout, and a coaxial outlet pas sage ending at said end face;

an inlet passage extending through said pump body and said cylinder means and communicating With the interior of the latter; a piston reciprocable in said cylinder means; drive means operatively connected to said piston for reciprocating the latter; a flat connecting member having substantially parallel faces and extending through said cutout into said large diameter portion of said bore with one of said parallel faces thereof abutting against said end face of said cylinder means, said connecting member being formed with passage means therethrough having an open end at said one of said parallel faces aligned with said outlet passage and communicating therewith; a pressure screw screwed into said threaded end of said bore and engaging with one end thereof the other of said parallel faces of said connecting member for pressing said one face thereof against said end face of said cylinder means and said shoulder face of said cylinder means against said shoulder face of said pump body; and a capillary tube connected at one end thereof to said connecting member communicating with the other end of the passage means therethrough, the other end of said capillary tube being adapted to be connected to the fuel injection system.

8. In a pump as set forth in claim 7, said passage means in said connecting member comprising a first portion extending axially aligned with said outlet passage from said one face of said connecting member into the latter, and a second portion extending substantially normal to said first portion from the latter to the outer surface of said connecting member, said capillary tube being connected to'an outer end of said second portion.

9. In a pump as set forth in claim 7 and including a valve member in said outlet passage movable between a closed and an open position, and said cylinder means including a spring plate engaging said valve member and biased so as to tend to maintain the latter in said closed position, said spring plate being formed with openings therethrough permitting passage of fluid through said openings when said valve member is in said open position, and an annular spacer member sandwiched between said spring plate and said one face of said connecting member and permitting flexing of said spring plate.

It). In a pump as set forth in claim 7, and including an annular spacer member sandwiched between said shoulder face of said bore and said shoulder face of said cylinder means for'adjusting the axial position of said cylinder means in said bore.

11. In an arrangement of the character described, in combination, body means formed with a cutout having an open end at the outer surface of said body means, said cutout extending from the outer surface of said body means into the latter and being in part defined by a face, said body means being also formed with a fluid passage having an open end at said face and with a threaded bore extending from a face of said cutout opposite said one face to the outer surface of said body means; a connecting member located in said cutout and dimensioned so as to be withdrawable through said open end thereof, said connecting member having an abutting face abutting against said one face of said body means and being formed with passage means therethrough having an open end in said abutting face of said connecting member and communicating with said fluid passage; a pressure screw threaded into said threaded bore of said body means and engaging with one end thereof a portion of said connecting member opposite said abutting face for pressing the latter against said one face of said body means; and a tube connected at one end thereof to said connecting member and communicating at said one end thereof with the other end of said passage means therethrough. I

12. In an arrangement of the character described, in combination, body means formed with a cutout having an open end at the outer surface of said body means, said cutout extending from the outer surface of said body means into the latter and being in part defined by a face,

having an open end at said face and with a threaded bore coaxial with said fluid passage and extending from a face of said cutout opposite said one face to the outer surface of said body means; a substantially flat connecting member located in said cutout and dimensioned so as to be withdrawable through said open end thereof, said connecting member having a pair of substantially parallel faces one of which abuts against said one face of said body means and being formed with passage means therethrough having an open end in said abutting face of said connecting member and communicating with said fluid passage; a pressure screw threaded into said threaded of the other of said parallel faces for pressing said one of said parallel faces of said connecting member against said one face of said body means; and a tube connected at one end'thereof to said connecting member and communicating at said one end thereof with the other end of said passage means therethrough.

References Cited by the Examiner UNITED STATES PATENTS 3,051,087 8/1962 Scholin 103154X MARK NEWMAN, Primary Examiner.

DONLEY J. STOCKING, Examiner.

bore of said body means and engaging with one end there- 15 W. E. COLEMAN, Assistant Examiner.

Claims

1. IN A PUMP FOR A FUEL INJECTION SYSTEM OF AN INTERNAL COMBUSTION ENGINE OR THE LIKE, IN COMBINATION, PUMP BODY MEANS; PUMPING MEANS IN SAID PUMP BODY MEANS HAVING AN INLET PASSAGE FOR FEEDING FLUID INTO SAID PUMPING MEANS AND AN OUTLET PASSAGE FOR DISCHARGING FLUID UNDER PRESSURE THEREFROM; CHAMBER MEANS FORMED IN SAID BODY MEANS AND BEING IN PART DEFINED BY A FACE AT WHICH SAID OUTLET PASSAGE ENDS; A CONNECTING MEMBER REMOVABLY LOCATED IN SAID CHAMBER MEANS AND ABUTTING AGAINST SAID FACE THEREOF, SAID CONNECTING MEMBER BEING FORMED WITH PASSAGE MEANS THERETHROUGH COMMUNICATING AT SAID FACE WITH SAID END OF SAID OUTLET PASSAGE; RELEASABLE PRESSURE MEANS CONNECTED TO SAID BODY MEANS AND ENGAGING SAID CONNECTING MEMBER FOR PRESSING SAID CONNECTING MEMBER AGAIST SAID FACE; AND A TUBE CONNECTED AT ONE END THEREOF TO SAID CONNECTING MEMBER AND COMMUNICATING AT SAID ONE END WITH SAID PASSAGE MEANS, THE OTHER END OF SAID TUBE BEING ADAPTED TO BE CONNECTED TO THE FUEL INJECTION SYSTEM.