GB2198793A

GB2198793A - A single-cylinder plug-in fuel injection pump for internal combustion engines

Info

Publication number: GB2198793A
Application number: GB08729259A
Authority: GB
Inventors: Jean Leblanc; Bernhard Schenk
Original assignee: Robert Bosch GmbH
Current assignee: Robert Bosch GmbH
Priority date: 1986-12-22
Filing date: 1987-12-15
Publication date: 1988-06-22
Anticipated expiration: 2007-12-15
Also published as: JP2663973B2; DE3643961C2; GB8729259D0; DE3643961A1; IT1223534B; GB2198793B; IN170534B; JPS63167069A; FR2608685A1; IT8723091A0; FR2608685B1

Abstract

A single-cylinder plug-in fuel injection pump with an angularly adjustable delivery quantity adjusting member 20 has an adjusting device (34) for presetting the desired delivery quantity and fixing this adjusted position until the pump is fitted in an internal combustion engine. The adjusting device (34) includes a setting member (35) for fixing in an adjusted position on the pump housing (11), the setting member having a longitudinally extending guide (38) into which a locking pin (37) can be inserted so as to position the delivery quantify adjusting member (20). In order to set the desired delivery quantity and subsequently to fix the adjusted position, the locking pin (37) is inserted into the guide (38) and into a recess (44) provided in the delivery quantity adjusting member (20). <IMAGE>

Description

DESCRIPTION A SINGLE-CYLINDER PLUG-IN FUEL INJECTION PUMP FOR INTERNAL COMBUSTION ENGINES.

The present invention relates to a single-cylinder plug-in fuel injection pump for internal combustion engines, in particular for multi-cylinder diesel engines.

Single-cylinder plug-in fuel injection pumps, or plug-in pumps, are advantageously used in internal combustion engines, which pumps have a low cylinder output in which the expenditure for an in line or distributor-type injection pump is too large or in which shorter pressure lines are to be used, and hence improved injection conditions obtained, to mount the injection pumps as close as possible to the injectipn nozzle of the associated internal combustion engine cylinder. Plug-in pumps do not have their own drive, but are driven by a camshaft of the internal combustion engine or motor. The injection quantity is controlled by way of a control rod in the internal combustion engine which, like the delivery quantity adjusting member of the plug-in pump, is disposed beneath the associated fastening flange inside the pump spigot of the internal combustion engine.

In order to avoid the necessity for complicated individual adjustment of the plug-in pumps in multicylinder internal combusion engines fitted with such pumps, and in order to ensure that plug-in pumps can be exchanged as required without readjustment being required, it is necessary to ensure that all the plug-in pumps of an internal combustion engine, whose delivery quantity adjusting members are coupled by way of the control rod of the internal combustion engine and are actuated jointly, deliver the same quantity of fuel for injection when their delivery quantity adjusting members are in the same respective position.To ensure this each plug-in pump is adjusted in the factory, using a test bench, to a desired delivery quantity which is the same for all plug-in pumps of the same series type, and the delivery quantity adjusting member is locked in this position. When the plug-in pumps have been fitted to the internal combustion engine and the control rod has been coupled to the delivery quantity adjusting members, this locking acticn is released.

A plug-in pump is known from DE-868 994 in which an intermediate sleeve is disposed between a regulating sleeve of the delivery quantity adjusting device which causes the pump piston to turn, and t pump housing.

This intermediate sleeve fixes the re ulating sleeve, by way cf ring nuts, to the pump housing by turning said regutet ing sleeve once a part touter delivery quantity has been adjusted as required. Once the plug-in pump has been mounted and the control rod of the internal combustion engine acts upon the regulating sleeve by way of a worm wheel, the regulating sleeve and intermediate sleeve remain coupled to one another, while both are released from the pump housing.

The construction of this adjusting device, which comprises an intemediate sleeve and ring nuts, is complex and requires manipulations which take up an undesirably large amount of assembly time.

Another such plug-in pump is known from DE-180 0919 in which the adjusting device has an eccentric which can be adjusted through a radial bore in the pump housing. The eccentric carries an eccentrically disposed adjusting stud, which engages in an axial groove in a cylinder sleeve in which the pump piston is axially displaceably guided. The cylinder sleeve is clamped in the pump housing with a pipe seal acting on the end face. When this clamping action is released, the pump housing may be turned relative to the pump piston by means of the eccentric and the delivery quantity can thus be adjusted. During adjustment, the delivery quantity adjusting device should be fixed in a predetermined position. Following adjustment, the cylinder sleeve should be fixed in the pump housing again by tightening the pipe seal.

This embodiment of an adjusting device is also of an expensive construction, because, in addition to the adjusting eccentric, the pump housing and cylinder sleeve must also be machined. Since the pipe seal also contains the pressure valve which defines the working chamber of the plug-in pump, the loosening of said seal leads to leakage which causes inaccurate setting of the delivery quantity and also prevents adjustment being carried out when the plug-in pump is being dr, çel~..

In accordance with the present invention there is provided a single-cylinder plug-in fuel injection pump for internal combustion engines, in particular for multi-cylinder diesel engines, having a pump piston, which is axially driven in a pump housing and which has an inclined control edge, whose stroke distance, with is adjusted by rotating the piston, determines the fuel delivery quantity from a control tore n the pump housing, a delivery quantity adjusting member, which acts at least indirectly on the pump piston to rotate it, and which can be connected to a control rod on the internal combustion engine side, an adjusting device, by which the delivery quantity adjusting member is set to a desired delivery quantity before the pump is fitted in the internal combustion engine, and which is then fixed on the pump housing, and is released following installation of the pump and coupling to the control rod, in which the adjusting device comprises a setting member which is held on the pump using and which has a guide running through it longitudinally, a fixing device for fixing the setting member on the pump housing in any position required, and a locking pin which can be releasably inserted through the guide and into the delivery quantity adjusting member, which pin rigidly connects the setting member to the delivery quantity adjusting device when the adjusting device is in a set or locking position.

As such the adjusting device for setting the desired delivery quantity and for ensuring that this set position is maintained by the delivery quantity adjusting device until it is fitted into an internal combustion engine has a very simple construction. The delivery quantity may be sufficiently accurately adjusted on a test bench and the adjustment may be fixed rapidly and reliably. Once it has been inserted into the pump inlet in the internal combustion engine, it can be released without the need for any tools. The manufacturing costs for the adjusting device are low, as are the necessary assembly costs, since it is easily assembled.

Furthermore, the delivery quantity may be ajdusted while the plug-in pump is operating.

The invention is described further hereinafter, by way of example only, with reference to the accompanying drawings, in which: Fig. 1 is an elevated plan view of one embodiment of a single-cylinder plug-in fuel injection pump in accordance with the present invention; Fig. 2 is a longitudinal section along the line Il-Il in Fig. 1; Fig. 3 is a schematic longitudinal section along the line III-III in Fig. 1; Fig. 4 is a side view of a locking pin of an adjusting device for the plug-in pump in Fig. 3; Fig. Is a perspective view of a setting ember for the adjusting device in Fig. 3; Figs. 6 to 8 show a longitudinal section through aternative embodiments of a setting member for the adjusting device; Fig. 9 shows the plug-in pump as in Fig. 3, with the locking pin of Fig. 4 in the locking position of the adjusting device; Fig. 10 is a plan view of the plug-in pump along the direction cf erro X in Fig. 9; Fig. 11 is a part of a view from belcw of an adjusting lever of the delivery quantity adjusting member in Fig. 9; Fig. 12 is a section through a closure for a fuel intake tube in the pump housing along the line XII-XII In Fig. 10;; Fig. 13 shows another embodiment of the plug-in pump in Fig. 3, with a locking pin which is in the locking position of the adjusting device; Fig. 14 is a schematic longitudinal section through a plug-in pump in the direction of the lines XIV-XIV in Fig. 15; Fig. 15 is a view from below of the disc-shaped adjusting member of the setting device in Fig. 14; and Fig. 16 is part of a section through a closing cap inserted into a through bore in the pump housing in Fig. 14.

Fig. 1 shows an elevated plan view of, and Fig. 2 of a longitudianl section through, a singl-cylinder plug-in fuel injection pump, hereinafter referred to as a plug-in pump, which is inserted into a housing 10 (Fig. 2), of an internal combustion engine. The plug-in pump has a pump housing 11, in which a pump cylinder 14 is secured in a kno .,ay by means of a screw-threaded tube 13 and with the interposition of a pressure valve 12. The tube 13 has a connection fitting 15 and a connection thread 16 for screwing a presssure line leading to an injection nozzle.A pump piston 17 is axially driven and rotatably guided inside the pump cylinder 14. The outer surface of the pump piston 17 has an inclined control edge 18, which co-operates with a control bore 19 in the wall of the pump cylinder17 to determine the delivery quantity.

To change the delivery quantity, the pump piston 17 is turned by a delivery quantity adjusting member 20 so that the stroke between the control edge 18 and the control bore 19 is altered. The delivery quantity adjusting member 20 has a regulating sleeve 20 with a control arm 22 coupled thereto and a driving pin 23 which is perpendicular to the control arm 22 and parallel to the axis of the regulating sleeve. The regulating sleeve 21 is connected to the pump piston 17 so as to be nonrotatable thereto, although it allows a lifting motion thereof which is caused by a cam drive of the internal combustion engine acting by way of a spring plate 24 on the base of the pump piston 17 and a return spring 25 acting against the cam drive.The pre-stroke of the pump piston 17 can be adjusted by the choice of the thickness of a shim 26 which is inserted between the rurt houslr 11 and the csing 10 of the internal orbustion engine. The pre-stroke is that part of the pump piston stroke which is covered by the end face of the pump piston 17 on the pump working chamber side up to the point at which the control bore 19 is closed.

The driving pin 23 engages in a slot-like counter-coupling part 8 on a control rod 9 of the ir.tern--1 combustion engine and is shown in cross section. When there are several plug-in pumps at intervals in the housing 1C, the control rod 9 of the internal combustion engine acts on all the driving pins 23 of the various plug-in pumps.

The working chamber 27 of the plug-in pump, which is defined by the pump cylinder 14, the end face of the pump piston 17 and the pressure valve 12, is connected to the control bore 19 and a leakage bore 28, which also serves as an additional inlet port. The openings of the bores 19,28 being open when the pump piston 17 is located in the bottom dead centre as shown (Fig. 2) and are sealed off during pump delivery. The control bore 19 is connected by way of an annular passage 29 to a fuel intake tube 30 having a connecting opening 31, which can be connected to a fuel intake line. When installed, the plug-in pump is secured to the pump housing 10 by means of two screws 7, shown in section (Fig. 1), located through oblong holes 32 in a fastening flange 33, which is in one piece with the pump housing 11.

Prior to being fitted in the internal combustion engine, the plug-in pump is adjusted using a test bench in a factory, to obtain a predetermined desired delivery quantity. To facilitate this, the pump housing 11 contains an adjusting device 34, by means of which the delivery quantity adjusting member 20 is turned, so as to set the desired delivery quantity, and is subsequently fixed on the pump housing 11 in the required position.

Once he adjusted plug-in pump has been fitted to the internal combustion engine, this fixing is released following the engagement of the driving pin 23 with the control rod 9 of the internal combustion engine.

Figs. 3 and 9 show the adjusting device 34 in detail.

In Fig. 9, it is shown in its setting and fixing position, and in Fig. 3, it is shown in its release position. It is necessary for the adjusting device in Fig. 9 to be in the setting and locking position during adjustment of the plug-in pump on the test bench and during storage or transport until the plug-in pump is installed in the internal combustion engine. The adjusting device according to Fig. 3 is in its release position following installation of the plug-in pump in an internal combustion engine. Before it 5s remc ed the adjusting device shoul A t be put into the locking position again.

The adjusting device 34 has an adjusting or setting member 35, which is held on the pump housing 11, a fixing device 36 for fixing the setting member 35 on the purr housIng 11 in any position desired, and a locking pin 37 (Figs. 4 and 9). The setting member 35 is provided with a guide 38 wW runs through it longitudinally and through which the locking pin 37 can be inserted up to the control arm 22 of the delivery quantIty adjusting member 20. The locking pin 37 is inserted at the en face into the control arm 22 and nence the control arm 22 is rigidly connected to the settIng member 35.

Figs. 3,5 and 9 show a first embodiment of a possible version of the setting member 35, whereby Fig. 3 is a side view of the setting member 35, Fig. 5 is a perspective view, and Fig. 9 a longitudinal section therethrough. The setting member 34 is in the form of an adjusting cylinder 39 in which the guide 38 is disposed as an axial through bore 40 at an eccentric distance from the cylinder axis. The adjusting cylinder 39 is held in an upper bore portion 411 of a stepped bore 41 in the pump housing 11. To do this, the adjusting cylinder 39 includes an elastically deformable cylinder portion 42, which has a slightly larger diameter than the cylinder.The adjusting cylinder 39 is retained in the upper bore portion t by virtue of the resilience of the cylinder portion 42 so that, when the adjusting cylinder 39 has been rotated for the purposes of adjusting the delivery quantity, self-locH.ing is achieved.

The upper side of the adjusting cylinder 39 has a slot 48 into which a tool, for example a screwdriver, can be inserted so as to turn the cylinder 39. A pilot pin 43 projects from the lower side of the adjusting cylinder 39 facing the delivery quantity adjusting member 20, which pilot pin projects through a lower bore portion 412 of the stepped bore 41 and extends towards the control arm 22 of the delivery quantity adjusting member 20. This pilot is concentrically aligned with the guide 38, so that the axial through bore 40 also passes through the pilot pin 43. The diameter cf the axial through bore 40 is slightly larger than the locking pin 37 in Figs. 4 and 9, so that it is easily guided through the bore.To accommodate one end of the locking pin 37, the control arm 22 of the delivery quantity adjusting member 20 has a recess 44 (Figs. 9 and 11) to which the locking pin 37 engages for a direction of adjustment thereof.

In the simplest case, the fixing device 36 is used to provide lock or seal 45 (Fig. 3) which connects the adjusting cylinder 39 to the wall of the tepped bore 41 which surrounds it. To this end, a blind bore 46 is provided in the pump housing 11 which terminates at a slight distance from the wall of the upper bore portion 411 and extends substantially radially towards the stepped bore 41. In the region of this blind bore 46, the adjusting cylinder 39 has a portion of casing, which covers at least a part of the periphery, and has a straight knurl 47. By inserting a caulking tool into the blind bore 46 and caulking the base of the bore, the seal 45 can be made in the form of a bead pressing into the straight knurl 47 and being formed from the material of the bore wall.

In order to adjust the plug-in pump, it is mounted in a known way on a testing bench. The driving pin 23 's conneted te ar aojustlng rod on the test bench and the delivery quantity of the plug-in pump is measured with the test berch being driven at a fixed testing speed. The adjusting device 34 is in its adjusting position as shown in Fig. 9, that is, the rod-shaped locking pin 37 pass-es through the axial through bore 40 in the adjusting cylinder 39 and its end projects into the recess 44 of the control arm 22 of the delivery quantity adjusting member 20, so that the adjusting cylinder 39 and the control arm 22 are rigidly connected to one another.To set the desired delivery quantity, the adjusting cylinder 39 is rotated by means of a screwdriver inserted into the slot 48 in the adjusting cylinder 39. The control arm 22 is rotated in the same way by way of t th.e 1 czig plr. 37, and the pump pIston 17 is rotated by way of the regulating sleeve 21. The adjusting cylinder 39 is rotated until the desired delivery quantity is reached. Then the adjusting cylinder 39 is undetachably fixed in the pump housing 11 by means of the fixing device 36 by making the seal 45 described above. Once in this fixed adjusted position, the plug-in pump can be removed from the test bench.

When the plug-in pump is being fitted in the internal combustion engine, the control rod 9 in the internal combustion engine, which was previously locked in the testing position, is coupled to the driving pin 23 of the delivery quantity adjusting member 29 and the pump housing 11 is secured by means of the screws 7. Then the rod-shaped locking pin 27 is removed from the adjusting cylinder 39 by withdrawing it axially. The bore 41 is covered by a closure cap 49.

In order to prevent the locking pin 37 falling out or being unintentionally withdrawn from the adjusting cylinder 39, the end region of the rod-shaped locking pin 37 is bent substantially at right angles (Fig. 4) and the right-angled portion projects right over the connecting opening 31 of the fuel intake tube 30. Once the adjust cylinder 39 has been sealed, a closure 50 is pressed into the connecting opening 31. The closure 50, which is shown in longitudinal section in Fig. 12, corprises a plug 51, which can be inserted or screwed into the connecting opening 31 and which has an outer thread or corrugation, and a cap 52 which is in one piece therewith and which covers te connecting opening 31.The cap 52 has a clip 53 into which the end of the bent portion of the locking pin 37 is clipped. Once the plug-in pump has been Installed in the internal combustion engine, the closure 50 must be removed in order to connect the intake line to the fuel intake tube 30, as a result of which the looking pin 37 iS is autoraLlally wIthdrawn from the closure 50. This reminds the fitter to unlock the adjusting device 34, so that this operation is not omitted bv mistake.

Fig. 13 shows a variant 37* of the locking pin 37 which ensures, in the same way, that once the plug-in pump has been fitted in the internal combustion engine, the looking pin 37* is pulled out to unlock the delivery quantity adjusting member 20. The length of the locking pin 37*, which is in the form of a plug-in rod 54, should be dimensioned so that it projects into the region of the connection fitting 15 on the pump housing 11, when the adjusting device 34 is in the locked position. The plug-in rod 54 has a grip 55 whose outer diameter is substantially larger than the diameter of the rod.The outer diameter of the grip 55 is selected such that it approaches the pressure line fitting 15 to such an extent that it is nc,t=possible to screw the pressure line leading to the injection nozzle onto the fitting. Only when the plug-in rod 54 has been removed from the adjusting cylinder 39 can the pressure line be placed onto the fitting 15 and connected thereto.

Figs. 6 to 8 show three other possible variants 35'-35"' of the embodiment of the setting member 35.

In all these cases, as in the case of the setting member 35 in Figs. 3,5 and 9, self-locking of the adjusting cylinder 39' (Fig. 6), 39" (Fig. 7) and 39"' (Fig. 8) is obtained in the upper bore portion -2'11 t or 411 " of the stepped bore 41' or 41" or in the through bore 41 ", In the embodiment of Fig. 6, this self-locking is achieved by virtue of interneshing threads or corrugations 56' or 57' on the inside wall of the upper bore portion 411' and on the outer surface of the adjusting cylinder 39'.

The adjusting member 35' or 35" can hence be manufactured in a Particularly economical manner from plastics, for example nylon.

In the embodiment of Fig. 7, self-locking of the adjusting cylinder 39" in the upper bore portion 411" of the stepped bore 41" is obtained using a locking screw 58", which can be screwed into a radial bore 59' ' having an internal thread 60", which bore is perpendicular with respect to the stepped bore 41 " . A stall plastic plate 61" is inserted between the end face of the locking screw 59' ' and the outer casing of the adjusting cylinder 39''. By prssing the small plastic plate 61'' moderately onto the adjusting cylinder 39", locking of said cylinder is achieved.By screwing the locking screw 28 " further, cylinder compression can be made so extreme that it is no longer possible for the adjustlrg cylinder 39'' to be rotated by way of the slot 38". Hence the locking screw 58" ' at the same time functions as the xing device 36" in the pump housing 11, following adjustment of the plug-in pump.

In the embodiment of the setting member 35"' in Fig. 8, self-locking and fixing of the adjusting cylinder 39''' is achieved by way of a spring, wave or crinkle washer 71, which rests firstly on a support face 72 on the lower side of the housing 11 or fastening flange facing the delivery quantity adjusting member 20 and secondly on a spring ring 73, which is held on the adjusting cylinder 39'''. The adjusting cylinder 39''' is provided with a support collar 74, by which it lies on the upper side of the housing 11 or fastening flange remote from the delivery quantity adjusting member 20. Teeth 75 on the outer surface of the support collar 74 enables the adjusting cylinder 39" ' to be rotated by means of a special key in order to set the delivery quantity.

In order to set the delivery quantity and to lock the adjusted plug-in pump, the locking pin 37"' is once again inserted through the through bore 40''' in the adjusting cylinder 39"' and, as before, its end engages in the recess 44 in the control arm 22 of the delivery quantity adjusting member 20. The end portion of the locking pin 27"' projecting out of the support collar 74 is bent, and its bent portion 77 projects over a fastening stud 76 which is shown in cross section in Fig. 8, and which is seated on the connecting opening 31 and projects away therefrom substantially at right angles thereto.In order to slide a connecting tube on to the fitting 76, the locking pin 37''' must be removed therefrom and also withdrawn from the adjusting cylinder 39"', and this reliably ensures that the locking pin 37"' is not left in by mistake following fitting of the plug-in pump on the internal combustion engine, which would result in the control rod being locked. The connecting opening 31 can form both the inlet to, and return from, the suction chamber.

Figs. 14 to 16 show a variant 134 of the abovedescribed adjusting device 34. Where the components are the same, the same reference numerals have been used, prefixed by a 1.

In this adjusting device 134, the setting member 135 is in the form of a setting disc 162, which is disposed on the underside of the pump housing or the fastening flange 133, which is integral with the pump housing 11, which represents the support side of the pump housing 11 on the housing 10 of the internal combustion engine. The thickness of the setting disc 162 can be altered in order to adjust the pre-stroke.

On the underside of the setting disc 162, which faces towards the delivery quantity adjusting member 20, is disposed a perpendicularly projecting pilot pin 163, in which a guide 138 is located in the form of semi-closed axial groove 164. Again, the locking pin 37 can be Inserted through this axial groove 164, at least in the direction of adjustment of the control arm 22 of the delivery quantity adjusting member 20 without any prny therebe'weer.. h through bore ss ÓD, which is flush with the guide 138, is provided in the pump housing 11 and its diameter is larger than the diameter of the guide 138. With the through bore 165 in this form, the locking pin 137, which passes through it, is able to follow a swivelling motion of the setting disc 162 relative to the pump housing 11.

In this embodiment of the adjusting device 134, the fixing device 136 for the setting member 135 comprises two diametricâlly opposed internally threaded bores 166 in the setting disc 162, corresponding oblong holes 167 in the fastening flanges 33, and two fixing screws 168 which pass through the oblong holes 167 and can be screwed into the internally threaded bores 166. Due to the nature of the longitudinal section in Fig. 14, made along the line XV-XV in Fig. 15, only the lefthand oblong hole 167, fixing screw 168 and internal thread bore 166 can be seen in Fig. 14. The setting disc 162 may be in the form of a simple blank, out of which the pilot 163 can be bent and formed.

In order to set the desired delivery quantity, with the plug-in pump clamped on the test bench, and the fixing screws 168 partially loosened, the pump housing 11 is rotated about the pump housing axis and relative to the setting disc 162, which disc is fixed on the test bench so as to be non-rotatable. Since the control arm 22 of the delivery quantity adjusting member 20 is rigidly connected to the locking pin 137, which pin 137 passes through the guide 138 and is inserted in the recess 144 in the control arm 22, to the setting disc 162, the pump cylinder 14, which is secured in the pump housing 11, is rotated relative to the pump piston 17, and hence the control bore 19 provided in the pump cylinder is rotated relative to the control edge 18 of the pump piston 17.As soon as the desired delivery quantity has been reached, the pump housing 11 is no longer rotated and the setting disc 162 is firmly connected to the pump housing 11 by tightening the fixing screws 168. The adjusting device 134 is now in its locked position, in which the plug-in pump can be removed from the test bench, stored, transported and installed in an internal combustion engine. Once the plug-in pump has been fitted, and secured to the internal combustion engine housing, and once the internal combustion engine control rod has been coupled to the driving pin 23, the locking pin 137 is pulled out of the setting disc 162 in the same way, so that the rigid connection between the setting disc 162, which is fixed on the purp housing 11, and the delivery quantity adjusting member 20, is released.The upper opening of the through bore 165 is then closed by inserting a closure cap 169 (Fig. 16). In order te fix the setting disc 162 onto the test bench, it has two diametrically opposed fixing grooves 170 to prevent overloading of the control arm 22.

The use of the adjusting devices 3k, 134 described above is not limited to plug-in pumps having a control arm 22 on the delivery quantity adjusting member 20.

x~ c adjusting devices 34, 134 can also be used in plug-in pumps whose delivery quantity adjusting members 20 have a small control rod in the pump, which, like the control arm 22, are connected by means of driving pins 23 to the counter-coupling parts 8 of the internal combustion engine control rod 9. The control rods in the pump each have recesses corresponding to the recesses 44 and 144 respectively for accommodating the locking pin 37,37"' or 137, or the plug-in rod 54.

Claims

CLAIIdS

1. A single-cylinder plug-in fuel injection pump for internal combustion engines, in particular for multi-cylinder diesel engines, having a pump piston, which is axially driven in a pump housing and which has an inclined control edge, whose stroke distance, which is adjusted by rotating the piston, determines the fuel delivery quantity from a control bore in the pump housing, a delivery quantity adjusting member, which acts at least indirectly on the pump piston to rotate it, and which can be connected to a control rod on the internal combustion engine side, an adjusting device, by which the delivery quantity adjusting member is set to a desired delivery quantity before the pump is fitted in the internal combustion engine, and which is then fixed on the pump housing, and is released following installation of the pump and coupling to the control rod, in which the adjusting device comprises a setting member whIch is held on the pump housing and which has a guide running through it longitudinally, a fixing device for fixing the setting member on the pump housing in any position required, and 2 locking pin which can be releasably inserted through the guide and into the delivery quantity adjusting member, which pin rigidly connects the setting member to the delivery quantity adjusting device when the adjusting device is in a set or locking position.

2. A pump as claimed in claim 1, wherein the delivery quantity adjusting device has a recess into which the end of the locking pin can positively engage, at least in the direction of adjustment of the delivery quantity adjusting device.

3. A pump as claimed in claim 1 or 2, wherein the setting member comprises an adjusting cylinder which can be rotated about its axis, in the pump housing, and in which the guide comprises an axial through bore, disposed at some distance from the cylinder axis.

h. A pump as claimed in claim 3, wherein the end face of the adjusting cylinder remote from the delivery quantity adjusting device is freely accessible and has a recess in which an adjusting tool can be inserted.

5. A pump as claimed in claim 4, wherein the recess comprises a transverse slot.

6. A pump as claimed in claim 3,4 or 5, wherein the adjusting cylinder is disposed in an upper portion of a stepped bore of the pump housing and has a pilot pin which is concentric with respect to the through bore and projects away from the lower end face, and which passes through the lower bore portion of the stepped bore.

7. A pump as claimed in claim 6, wherein the adjusting cylinder has an elastically deformable cylinder portion whose diameter is slightly larger than the diameter of the cylinder.

8. A pump as claimed in claim 6, wherein the inside wall of the upper bore portion of the stepped bore and the outer surface of the adjusting cylinder, which is preferably made of a plastics material such as nylon, are provided with intermeshing corrugations or a screw-in thread.

9. A pump as claimed in claim 8, wherein said plastics material comprises nylon.

10. A pump as claimed in any of claims 5 to 9, wherein the setting member fixing device is in the form of a seal, connectIng the bore wall cf the stepped bore to the adJusting cylinder.

11. A pump as claimed in claim 10, wherein the seal is in the form of a material bead pressed out of the wall of the stepped bore and into the adjusting cylinder.

12. A pump as claimed in claim 11, wherein a blind bore is provided in the pump housing, the end of ic is at a slight distance from the w-1 rf the upper bore portion of the stepped bore, is radial with respect to the stepped bore, and has a diameter which permits the insertion of a caulking tool.

13. A pump as claimed in claims 6 or 7 and 11 or 12, wherein the adjusting cylinder has a casing, which extends at least over a part of the periphery thereof, with a straight knurl, which when the cylinder is disposed in the stepped bore, is in the region of the material bead.

14. A pump as claimed in claim 6, wherein a radial bore is provided in the pump housing, which opens in the upper bore portion of the stepped bore and in which a fixing screw can be screwed, which can be pressed onto the casing of the adjusting cylinder.

15. A pump as claimed in claim 1 or 2, having at least one fastening flange, which is preferably integral with the pump housing, which, once the pump has been installed, rests on a flange support on the internal combustion engine, wherein the setting member is in the form of a setting disc, disposed on the support side of the fastening flange, and a through bore is provided in the pump housing or in the fastening flange on the side of the setting disc re.mote from the delivery quantity adjusting device and in alignment with the guide, which bore has a diameter which is larger than the diameter of the guide.

16. A pump as claimed in claim 15, wherein the setting disc has a pilot pin, which is provided with the guide and which projects substantially at right angles from the disc face facing the delivery quantity adjusting device, and the guide is in the form of a semi-closed axial groove in the pilot pin of the setting disc.

17. A pump as claimed in claim 15 or 16, further comprising a closure cap which can be placed on the opening of the through bore remote form the setting disc following removal of the locking pin.

18. A pump as claimed in any of claims 15 to 17, wherein the setting member fixing device has at least one internally threaded bore disposed in the setting disc, at least one corresponding oblong hole in the pump housing or in its fastening flange, and at least one fixing screw, the shaft of which passes through the oblong hole and is screwed into the internally threaded bore.

19. A pun as clalmed in any of claims 15 to 18, wherein the setting disc has two fixing grooves for fixing to, and adjustment on, a test bench.

20. A pump as claimed in any of claims 15 to 19, wherein in order to set the pump piston pre-stroke, the setting disc can have various axial thicknesses.

21. A pump as claimed in any of claims 15 to 20, wherein the setting disc Is In the for of a blank part.

22. A pump as claimed in any of claims 1 to 21, wherein the locking pin is in the form of a plug-in rod, which can be plugged into and pulled out of the guide, and whose diameter corresponds to the diameter of the guide.

23. A pump as claimed in claim 22, wherein the end region of the locking pin which projects out of the pump housing is bent, and this bent end is connected to a closure which can be placed on a fuel intake tube of the pump housing.

24. A pump as claimed in claim 23, wherein the closure has a plug which can be inserted into the tube opening, and a cap, which is integral therewith and covers the end face of the fuel intake tube, which cap has a clip in which the bent end of the locking pin can be clipped.

25. A pump as claimed in claim 22, wherein the locking pin which is in the form of a plug-in rod, is formed in such a way that, when the adjusting device is in the locking position, it projects out of the pump housing into the region of a fitting for an injection pressure line, and carries a grip at the end, which grip projects beyond the rod diameter, and towards the fitting, such that it is not possible to screw the injection pressure line onto the fitting.

26. A pump as claimed in any of claims 1 to 3, wherein the adjusting cylinder is disposed in a through bore in the pump housing and has a support collar on the side of the pump housing remote from the delivery quantity adjusting device which projects above the through bore, and the setting member fixing device has a spring or crinkle washer, which is fastened to the adjusting cylinder and is also supported on the pump housing on the side facing the delivery quantity adjusting device.

27. A pump as claimed in claim 26, wherein the spring or crinkle washer is held by means of a spring ring on the adjusting cylinder.

28. A pump as claimed in claim 26 or 27, wherein the support collar is provided with a locking part for the insertion therein of an adjusting tool.

29. A pump as claimed in claim 28, wherein the locking part is in the form of a plurality of teeth, which extend about the periphery of the support collar and into which a special key is inserted.

30. A pump as claimed in any of clei 26 to 29, whereIn the end portion of the locking pin projecting out of the support collar is bent at right angles, and when the adjusting device is in the locking position, it partially covers a fitting for a fuel intake or fuel Injeotion line.

31. A single-cylinder plug-in fuel injection pump for internal combustion engines substantially 2S hereinbefore described with reference to and as illustrated in the accompanying drawings.