DE2261988A1 - INJECTION PUMP - Google Patents

Description

Düssaidorf, December 18, 1972 PL / Yes Register: 2267/68

ROTO DIESEL, 98 Boulevard Victor-Hugo, Clichy (Hauts-de-Seine), FRANCE

Injection pump

The invention relates to an injection pump for fuel in internal combustion engines, consisting of a body in which a distributor in on to the injection pump belonging machine is rotatable in a coordinated manner, with a pair of pump pistons in a transverse direction provided in the manifold Bore is displaceable, the outer ends of which have radial slots in which a pair of shoes for rollers are movable, which shoes attack the piston during insertion and wear cam engagement elements that with Internal cams of a circular cam ring surrounding the manifold engage as the manifold rotates and push the rollers with their shoes and the pistons inwards, furthermore a fuel supply for the Delivery of the fuel taken up by the bore to several fuel outlets and a fuel inlet for The bore warend the outward piston movement exist * and wherein the distributor carries a stop bracket, the end portions of which are so in the path of movement of the shoes

309826/0376

- 2

lie that they are their outward movement and thus that of the pistons and the maximum amount of fuel that the injection pump can deliver, limit.

Injection pumps of this type are known; one of the tasks to be solved with such an injection pump is to to provide additional fuel during starting, but it is essential that under normal operating conditions no more than a predetermined maximum amount of fuel is supplied to the machine, which maximum amount is less than the one for starting the machine.

The invention is based on the object of designing such a pump in a simple and reliable manner, in which additional fuel is available to start the machine.

According to the invention, this becomes the introductory part of an injection pump described type achieved in that the contact surfaces of the shoes and the end portions of the stop bracket are designed such that a relative movement of the shoes and the end portions of the stop bracket in the axial direction the permissible outward movement of the pistons changed.

In another embodiment of the invention, the contact surfaces form of the shoes and the end sections of the stop bracket have a recess, the shoes relative to the end sections of the stop bracket are movable so that there is an additional outward movement of the shoes, in which a additional amount of fuel flows into the pump.

The invention can also be implemented in such a way that the end section of the abutment bracket B was spaced apart axially Teeth are structured, which recesses at the contact surfaces of the shoes in which the teeth correspond

309828/0376

■ 2261968

Relative movement of the shoes and the stop bracket B intervene and thereby the permissible outward movement of the shoes enlarge »-

Finally, according to the invention, the shoes can be axially displaceable relative to the distributor.

Examples of injection pumps for fuel according to the invention are carried out are described below with reference to the drawings. Show in it;

1 shows a cross-sectional representation of an exemplary embodiment, "" "■ '■ -

FIG. 2 is a cross-section along line 2-2 of FIG.

3 shows a cross section of part of the shown in FIG.

set the pump in one position, FIG. 4 shows a representation corresponding to FIG. 3 with the mentioned parts in a different position.

Fig. 5 shows a development of a cam and

Figures 6, 7, 8 and 9

optional pump designs.

In FIGS. 1 and 2 of the drawings, a body 10 can be seen in which the rotatable, cylindrical distributor is located 11 is located, which is drivable via its one end portion in a predetermined relationship to the machine, the is in communication with the pump. At the other end section of the distributor you can see the rotation section 12 of a Impeller pump with an inlet 13 connected to the fuel supply is in communication, and an outlet IM · for the pressurized fuel. The output pressure of the pump is controlled to the extent that it is dependent on the

309826/0376

Changes the speed at which the distributor is driven, which is not shown in the drawing Pressure relief valve takes place.

The distributor is with a transversely penetrating hole 15 executed, in which a pair of reciprocating pump pistons 16 is located. The pistons 16 are with their outer ends of shoes 17, which can be moved radially in radial slots of the distributor and each one role wear. The rollers cooperate with a circular cam ring 19 within the body, from the inner periphery thereof project several cams, the Komtur enlarged in Fig. 5 can be seen. The pistons 16 form together with the rollers and the cam, a high pressure injection pump; the gap between the pistons 16 stands with one extending in the longitudinal direction Channel 20 of the distributor in connection · The channel 20 is at one end with radially arranged supply lines 21 in Connection, which in turn are connected to a plurality of outlet openings 22 in said body, which in turn with the respective Injectors of the associated machine are connected. The connection of the feed channel 21 with the outlet 22 takes place during the time during which the pistons are moving inward.

The one extending in the longitudinal direction is in another position Channel 20 with four radially extending inlet openings 23 in connection, which in turn when the manifold is rotated come into communication with an inlet port 24 in the body. The inlet port 24 is connected to the outlet 14 of the Pump in connection; An adjustable throttle 25 is used to adjust the amount of fuel that passes through the opening 24 to flow to the injection pump, while the opening 24 with an inlet port 23 is in communication.

09826/0 376

During operation, when the piston moves inwards, fuel is displaced into an injection nozzle of the associated machine, whereupon with further rotation of the distributor, the feed line 21 is moved towards the outlet 22 and a the inlet openings 23 pushes into the region of the opening 24. In the process, fuel flows into the transverse bore 25, and the pistons move outwards, so that a new fuel filling is available for the associated machine when the pistons 16 move inward next time.

Pumps of this type are known; the maximum amount of fuel set, which is fed to the machine during normal operation regardless of the setting of a throttle can be, a stop is provided which limits the maximum outward movement of the pistons 16. As can be seen from Fig. 2 can be seen, a stop bracket 26 is used, which is in its position relative to the distributor 11 with an adjusting screw 27 is held «The stop bracket is made of elastic material and has end sections 28 that are bent so that that they lie in the path of movement of the respective shoes 17. The command of the distributor is chosen so that when it is tightened of the screws 27 move the end portions outward to allow the spacing of the pistons to increase. The It can be seen from FIGS. U and 3 that the end sections 28 are cut out in such a way that several teeth are formed, with the outer surfaces of the shoes 17 are also complementary Have wise incisions. It can also be seen from Figures 3 and 4 that the shoes with respect to the stop bracket 26 in are movable in the axial direction. At Fig, H have the shoes taken the position for additional fuel so that the teeth can enter recesses in the shoes. at Fig. 3 are the shoes in the normal supply position for fuel, with the teeth not entering the recesses can. It can therefore be seen that with the position of the parts in Fig. U an additional outward movement of the shoes

309826/0376

and so the piston can be made so that £ more fuel is available · As can be seen from FIG. 5, a downward movement of the rollers corresponds to that shown in FIGS Outward movement, the N position corresponds to normal fuel supply, while the S position corresponds to additional fuel during starting is essential.

In Figures 1 and 4, the parts are shown in the position in which additional fuel is delivered} the shoes 17 Transferring them to their normal position. In order to be able to carry out such a movement, the shoes are designed with actuating elements 29. These are channel-shaped, with the Attack side walls at the ends of the rollers 18 and shoes. The bottom walls of the actuating elements are formed with elongated openings through which the Pistons extend to come into contact with the shoes. Furthermore, the actuating elements are uniform with Actuating rods 30 running, which extend continuously and are in engagement with an actuating disk 31, which is movably attached to the distributor. The operating rods are designed with grooves 32 at their other ends, which are supported on the disk 31. The disc is held at a distance from the pistons by compression springs 33 surrounding the rods; the springs lie between the disc and a stop plate 3H, which is firmly connected to the distributor in the axial direction and in the direction of rotation stands.

The disc 31 is held in the position shown by means of a pawl, with a pivotable part 35 in a Groove of the distributor is provided. The part 35 has an end portion which is designed to be connected to the end portion a sleeve can be engaged, which is part of the

Ί09826 / 0376

Forms disc and is held in the locked position shown under the action of an elastic band. In the special exemplary embodiment, a piston 26 which can be actuated by means of a fluid pressure within a cylinder provided in the distributor is used to release the locking. The cylinder is in communication with the outlet Ik of the pump; if the delivery pressure of the pump increases after the machine has been started, the piston moves towards the pawl in order to loosen the disc 31 which, under the action of the springs, simultaneously moves axially with respect to the shoes in that shown in FIG Position shifts. This shift cannot occur immediately when the pawl is released, but it takes place as soon as possible when the pump pressure no longer acts on the rollers. In order to facilitate said movement, the side surfaces of the teeth and recesses are inclined as shown in FIGS. 3 and k.

The movement of the disc into the position corresponding to the additional fuel is carried out by a movable part 37 causes, which can be seen in Fig. 1 in dashed lines. If this part is towards the Piston is moved, it touches the disc 31, which also moves axially and in this position of. the handle 3 5 is held.

In the embodiment according to FIG. 6, a sleeve 38 surrounds the Distributor and is axially displaceable to the normal and to be able to take the position provided for additional fuel. A stop made up of two oppositely directed movable, spring-loaded stop parts 39 is located in the distributor and engages in recesses in the sleeve 38 a. In the drawing, the parts assume a position in which the normal amount of fuel is delivered. For the movement of the parts into the position in which additional

309826/0376

Fuel is to be delivered, a part 40 is used, which engages a flange of the sleeve. A movement this part overcomes the force directed on the stop parts, so that the sleeve is in its other position can move. Furthermore, means 4l are provided to push the sleeve back to its original position when the machine is to be started. This means 41 can be a device that can be operated by centrifugal action,

. ■ ': ' ■ '■. ■■ ... ■ ι ¹ '■,

which is responsive to the speed of rotation of the machine or distributor. The facility can therefore be the usual Be the centrifugal regulator of the pump to control the setting of the throttle 2 5. In any case, these are part 40 or its controls are chosen so that additional fuel can only be delivered when the engine is at a standstill.

According to the embodiment shown in Fig. 7, the sleeve is 42 under the action of a spring 43 in a position in which additional fuel is supplied. You can put the sleeve in move their opposite position by acting on the pistons 44 in cylinders of the body. The pistons act on a pressure ring 45, which rests on the actuation ε elements η, who wear the rollers and the shoes. As can also be seen from the figure, an additional spring 46 is included a stop ring 47 is provided for contact with the sleeve. If the sleeve touches the stop ring, there is an additional load for the sleeve movement; in Connection with other attacks, which are not shown and can have a customary design, the curve of largest possible fuel delivery designed in a form, which depends on the speed of the machine.

The arrangement shown in Figs. 8 and 9 shows that the distributor 11 is designed with a helical, splined section, the helical wedges 48

309826/0376

which engage in corresponding grooves on the inner circumference of a ring 49 which surrounds the distributor. With the The end face of this ring is engaged by a pair of oppositely opposing actuating elements 50, which are made uniformly with a ring 51 which is displaceable on a flat section of the distributor. The actuating elements are provided at an angle and are complementary Grooves 52 housed in an enlarged portion of the manifold. The elements are expediently under the same angle as the helix angle of the wedges.

The actuating elements are formed with slots 53 in which the shoes are located, which in turn carry the rollers. Furthermore, the bottom walls of the slots are provided with openings in such a way that the pistons 16 can pass through in order to come into engagement with the shoes. The actuating elements are loaded in a direction in which additional fuel is to be supplied by means of a spring 5H j they are pressed in the opposite direction by the pressure of a fluid which acts on pistons as in the embodiment of FIG. As in the exemplary embodiments already described, a stop bracket 55 is designed with teeth (not shown in the drawing), the shoes also having corresponding recesses. When the actuating elements are displaced by means of the pistons, the outward movement of the rollers is limited in the manner described, however, due to the inclined grooves, the rollers move at an angle to the axis of rotation of the distributor, whereby the injection of the fuel can be adjusted.

309826/0376

Claims (1)

PATENT CLAIMS: The invention relates to an injection pump for fuel in internal combustion engines consisting of a body in which a distributor can be rotated in a manner adapted to the machine belonging to the injection pump, a pair of pump pistons being displaceable in a transverse bore provided in the distributor have outer ends radial slots in which a pair of shoes for rollers are movable, which shoes engage the piston when pushed in and cam engagement selemente carry which come into engagement with inner cams of a circular cam ring surrounding the distributor when the distributor rotates and the rollers with push their shoes and the piston inward, furthermore there is a fuel supply for the delivery of the fuel taken up by the bore to a plurality of fuel outlets and a fuel inlet to the bore during the outwardly directed piston movement, and wherein the distributor has a stop b bears, whose end sections lie in the path of movement of the shoes in such a way that they limit their outward movement and thus that of the pistons and the maximum amount of fuel that the injection pump can deliver » daduroh marked _Λ that the contact surfaces of the shoes (17) and the end sections (28) of the stop bracket (26) are designed such that a relative movement of the shoes (17) and the end sections (28) of the stop bracket (26) in the axial direction changes the permissible outward movement of the pistons (16). Injection pump according to the preamble of claim 1, characterized in that the contact surfaces of the shoes (17) and the end sections (28) of the stop bracket (26) form a recess, and that the shoes (17) relative to 309826/0376 the end sections (28) of the stop bracket (16) so movable are that there is an additional outward movement the shoes (17) results in which an additional amount of fuel the pump flows. . , Which recesses correspond to 3. An injection pump according to the preamble of claim 1, since by in _t that the end portions (28) of the stop bracket is divided into a plurality of axially spaced teeth (26) at the contact surfaces of the shoes (17), in which the teeth in Engage relative movement of the shoes (17) and the stop bracket (26) and thereby increase the permissible outward movement of the shoes (17), k. Injection pump according to claim 3, characterized dadureh _t that the shoes (17) axially movable relative to the distributor (11), 5. An injection pump according to claim H, wherein _t that actuating elements with the corresponding shoes (17) are in engagement, which in turn are connected to a part which is axially displaceable on the distributor and rotating therewith, 6. An injection pump according to claim 5, characterized in _a that the actuating part is designed channel-shaped, wherein the end walls of the channel engage in corresponding · ends of the respective shoe, is executed while the bottom wall of the channel with an opening through which protrude the respective piston, 7. An injection pump according to claim 6, characterized in that ₃ stop elements (39) are provided, which keep the actuating elements in the relevant for additional fuel position, and that the actuating elements 309826/0376 12th springs to the amount corresponding to the normal amount of fuel Position are pressed when the Anechlagelemente are released. 8. Injection pump according to claim 7, characterized in that the stops consist of a pivotable part, one end of which is designed for engagement with the part with which the actuating elements are connected, and that furthermore the pivotable element is held elastically in this position , and that parts which can be actuated by means of pressure are provided which release the pivotable part from engagement with the part and thus enable the actuating elements to move the shoes into the normal position corresponding to the highest possible fuel supply, 9. Injection pump according to claim 8, characterized in that means are provided for moving the actuating elements into the position which correspond to an increased fuel delivery. 10. Injection pump according to claim 9, characterized in that the springs pressing on the actuating parts each surround rods which connect the actuating parts to the aforementioned parts, i. 11. Injection pump according to claim 10, characterized in that the teeth and recesses have inclined walls such that the axial displacement of these parts is facilitated, 12. Injection pump according to claim 7, characterized in that the stops consist of a pair of outwardly spring-loaded stop parts which are located in a bore of the distributor and in a corresponding pair of recesses 309826/0376 13th "2261908 engage in a sleeve which forms the part to which the actuating elements are connected. 13. Injection pump according to claim 12, characterized in that a further pair of depressions is provided, by means of which the actuating parts are held in the position for the normal, highest possible amount of fuel. I ¹ U injection pump according to claim 13, characterized in _Λ that means are provided for the movement of the operating parts in the position for additional fuel supply, and in that further means are operable / transfer to the operating members in the corresponding normal maximum fuel amount position. to 15. Injection pump according to claim m » characterized in that a device which can be actuated by centrifugal action and which is responsive to the speed of the associated machine is provided as further means. 16. Injection pump according to claim 15, characterized in that the means which can be actuated by centrifugal action form part of the controller of the pump, 17. An injection pump according to claim 15, characterized in _t that the teeth and recesses have inclined side walls, to facilitate an axial displacement " 18. An injection pump according to claim 6, characterized in _Λ that the actuating means of the additional fuel quantity corresponding position are elastically pressed in the direction of the. 309828/0376 2261388 19. Injection pump according to claim 18, characterized in that actuatable by the pressure of a fluid means are provided for the movement of the actuating parts in the direction of the position corresponding to the normal maximum possible fuel amount. 20. Injection pump according to claim 10, characterized in that the elastic means consist of a helical compression spring which press on the part to be connected to the actuating parts, 21. Injection pump according to claim 20, characterized in that a further helical compression spring is provided which acts on the part after a predetermined movement of the same has taken place against the action of the helical compression spring, the pump having additional stop parts for the shoes, and wherein the pressure of the fluid for actuating the associated means is derived from a point, the output pressure of which is variable in accordance with the drive speed of the machine. 22. Injection pump according to claim 21, characterized in that »said point is provided with a feed pump which supplies fuel to the injection pump and is provided with a pressure control valve. 23. Injection pump according to claim 22, characterized in that the means which can be actuated by the pressure of a fluid have a plurality of pistons. 21. Injection pump according to claim 6, characterized in that the actuating parts run obliquely in complementary slots of the distributor in such a way that when the actuating parts move axially, the rollers experience a rotary movement about the axis of rotation of the distributor. 309826/0376 25. An injection pump according to claim 2H, characterized in _Λ that the actuating members against the action of elastic
Means are movable by a piston that can be acted upon by a fluid * _Λ that a ring between the operating members and the piston 26 is provided "injection pump according to claim 25, characterized in that 27, injection pump according to claim 26, characterized in _Λ that the ring is supported on the helical splines of the distributor ' 3 0 9826/0376 Less than 6th