DE3806669C2 - - Google Patents

Description

State of the art

The invention relates to a fuel injection pump according to the Genus of the main claim. In such a known from DE-AS 11 56 605 The fuel injection pump is supplied with the Pump workspace over a the fuel injection quantity per Delivery stroke of the pump piston controlling variable inlet throttle, which in the Filling channel is arranged. With part load operation of the associated The internal combustion engine is thus the pump workspace at the end of the Suction strokes are not completely filled with fuel, so that Suction forces on the known fuel injection pump freely movable plug and the spool assembly act that here consists of a control sleeve that has a spring that Starting spring, which is coupled to a piston, which is the control piston forms. This leads to undesirable wear on the system of the Plug on the stop pin. With the control sleeve is starting The pressure in the control pressure chamber is limited by the start excess effective pump piston delivery stroke by advancing the opening of the Tax opening is shortened, but is in the known Fuel injection pump no possibility of alignment Delivery characteristics of the fuel injection pump to the Fuel requirement of the internal combustion engine, especially at Full load operation provided.

The object of the invention is the fuel injection pump mentioned above so that exact control of the fuel injection quantity with speed-dependent adjustment of the full-load injection quantity to the requirements of the internal combustion engine on simple and easily adjustable way is achievable and the input mentioned disadvantages can be avoided.

This object is achieved by the characterizing features of the main claim solved. This has the advantage that with the help of the ring slide, the effective delivery stroke of the pump piston on a fuel column under constant delivery pressure is geometrically adjustable and by an additional Variation of the effective pump piston stroke by changing the Start of delivery or end of delivery the full fuel injection quantity is adjusted. At the same time, according to further training Claim 3 one at the start of the internal combustion engine or with the beginning Operation of the fuel injection pump automatically working Switching off in an equally simple way using the control piston provided multiple starting injection, which is advantageous the full load injection quantity is upstream and therefore already one The start of injection is adjusted at the start. This relieves the construction of the injection start adjustment device, the can now have a smaller working stroke. Furthermore, with increasing speed one of the actual fuel injection quantity upstream adjustment injection quantity can be reduced.

By the configuration according to claim 4 in conjunction with claim 5 results advantageously in the basic structure of the fuel injection pump same structure but modified spool a negative adjustment, i.e. one with increasing speed increasing full load of fuel injection for certain needs in internal combustion engines. According to Claim 5 by changing the advance stroke in connection with the Design according to claims 2 to 3 a positive approximation the fuel injection quantity, that is, a reduction in Full load injection quantity with increasing speed can be achieved.  

Through the development according to claim 7, a constant delivery end of the high-pressure delivery of the pump piston of the fuel injection pump is achieved and thus the possibility is offered that an exact cut-off point can be maintained by the ring slide can be set at full load so that it only h for a later stroke of the pump piston delivery stroke _FE opens the longitudinal channel. According to claim 7, the end of delivery at normal full load position of the ring slide is no longer determined by the ring slide but by the connection of the outlet opening to the outflow channel. Thus, the ring slide can run through a small initial stroke when it reaches the end or cut-off speed until it opens the outlet opening of the longitudinal channel. In this way, vibrations and hysteresis influences during the control are reliably avoided, so that an exact control point is obtained. By switching off the relief of the pump workspace when the pump piston delivery stroke h _{FE is reached,} according to the development according to claim 7, a starting quantity is advantageously provided in addition to that according to claim 8, which is subordinate to the full-load injection quantity with regard to the injection process, that is to say has an effect which adjusts the start of injection. This is desirable in special applications.

With the further development of the subject of claim 2 is according to Claim 10 in the same way in the basic structure Fuel injection pump by changing the design of the easily replaceable control piston a negative adjustment of the fuel injection quantity, thus an increasing injection quantity increasing speed of the internal combustion engine achieved. Here results the position of the share of the starting quantity in the high-pressure production that it connects to the full-load fuel injection quantity without to change the start of spraying.

Advantageously, in addition with the help of a throttle Claim 12 achieved a speed-dependent, negative adjustment will.  

drawing

Five exemplary embodiments of the invention are shown in the drawing and are explained in more detail in the description below. In the drawings Fig. 1 shows a first embodiment of the invention; Fig. 2 is a control diagram for the embodiment of Fig. 1, Fig. 3 shows a variant of the exemplary embodiment of FIG. 1 with a separate Start piston for setting a start More injection amount, Fig. 4 shows a third embodiment of the Invention with negative adjustment, FIG. 5 shows a control diagram for the embodiment according to FIG. 4, FIG. 6 shows an embodiment variant of the embodiment according to FIG. 4, FIG. 7 shows a fifth embodiment of the invention with negative adjustment and FIG. 8 shows a control diagram for the fifth embodiment according to Fig. 7.

Description of the embodiments

In a housing 1 of a fuel injection pump, a pump piston 4 is arranged in a guide cylinder 2 of a cylinder liner 3 inserted into the housing, which pump piston is set into a reciprocating and at the same time rotating movement by means not shown. The pump piston is designed as a stepped piston, its larger part 6 , which is configured as a distributor, being guided in the guide cylinder 2 . The part 7 , which is smaller in diameter, emerges from the guide cylinder and projects into a cylinder 9 , which at the end connects to the cylinder liner 3 in the housing of the fuel injection pump. The cylinder 9 is sealed on the side opposite the cylinder liner 3 by a closure part 10 , which is screwed into the housing 1 lying there coaxially to the pump piston axis. Also coaxially to the pump piston axis, the closure part 10 is penetrated by a stop bolt 12 which is held in the closure part by a thread 13 , is adjustable and can be fixed from the outside by a lock nut 14 . The cylinder 9 is sealed to the outside by a sealing ring 15 on the stop pin 12 . In the cylinder 9 is a control piston 18 in the form of a sleeve 21 with a bore 22 which is tightly displaceable on the smaller diameter pump piston part 7 . On the opposite side, a plug 24 dips into the bore 22 , which is also tightly guided in the bore and encloses a pump working chamber 25 between its end face and the end face of the smaller-diameter pump piston part 7 . The stopper 24 is held in abutment on the end face of the stop pin 12 by a compression spring 27 , which acts on the control piston 18 to support a spring plate 28 connected to the stopper. The compression spring 27 serves as a starting spring.

The spring plate 28 lies against a collar 29 of the stopper 24 or is part of the same. The collar 29 is the base of a matching spring 30 , which rests on a shoulder 31 of the control piston 18 and can be designed, for example, as a plate spring. The end face 26 of the control piston on the plug side serves as a stop for the control piston on the collar 29 and thus indirectly on the stop bolt 12 , since the stopper 24 is held in contact with the latter by the compression spring 27 . At the same time, the end face 26 of the control piston 18 limits the deflection of the adjustment spring 30 . The control piston 18 divides the cylinder 9 delimited between the closure part 10 and the cylinder liner 3 into a control pressure chamber 32 , which lies between the control piston and the cylinder liner, and a relief chamber 33 , which is connected via a relief channel 34, for example, to the suction side of a fuel feed pump 36 , which consists of a Fuel reservoir 37 promotes fuel in an interior 38 of the fuel injection pump. The fuel delivery pump is driven synchronously with the drive speed of the fuel injection pump and, together with a pressure control valve 39, forms a speed-dependent pressure in the interior 38 in a known manner. This interior is in constant communication with the control pressure chamber 32 via a pressure line 40 .

From the end face of the smaller diameter pump piston part 7 , a longitudinal channel 41 leads through the pump piston and opens via a transverse bore 42 on the lateral surface of a part of the larger diameter pump piston part 6 protruding into the interior 38 on its drive side. The outlet 45 of the transverse bore, which is also the outlet of the longitudinal channel 41 , is controlled by a control edge 43 , which is arranged on an annular slide 44 which can be displaced tightly on the pump piston part 6 . The ring slide 44 represents the quantity control element of the fuel injection pump and can be adjusted by a regulator (not shown here) which is known per se via a control lever 47 . The higher the ring slide 44 is set, the longer the effective pump piston delivery stroke in the delivery end control shown here until, by opening the outlet 45 , the pump working chamber 25 is relieved to the interior 38 via the longitudinal channel 41 .

To fill the pump work space, a radial bore 48 branches from the longitudinal channel 41 in the region of the guide cylinder 2 from the longitudinal channel 41 to a filling opening 50 provided in the lateral surface of the larger diameter pump piston part 6, which opens with the rotation of the pump piston during its suction stroke with one opening into the guide cylinder Filling channel 51 overlaps. This branches off from the pressure line 40 and can be shut off by a shut-off solenoid valve 53 . The connection between the pressure line 40 and the control pressure chamber 32 takes place via a longitudinal groove 46 in the lateral surface of the cylinder liner, connecting the filling channel 51 to the control pressure chamber, and can therefore be shut off with the shut-off solenoid valve 53 . Instead of only one filling opening 50 and one filling channel opening, several of them can also be arranged distributed around the circumference of the pump piston. In any case, however, the filling opening 50 is permanently connected to an annular groove 52 serving as an outlet opening of the longitudinal channel 41 in the lateral surface of the larger-diameter part 6 of the pump piston, the annular groove 52 and thus the pump working space independent of the rotational position of the pump piston after a delivery stroke h _FE comes in contact with the filling channel 51 and thus fundamentally ends the high-pressure delivery of the pump piston.

Furthermore, a radial bore 54 branches off from the longitudinal channel 41 to a distributor opening 56 in the lateral surface of the larger diameter pump piston part 6 . This distributor opening is alternately connected with each pump piston delivery stroke to one of a plurality of pressure channels 57 distributed from the guide cylinder 2 distributed around the circumference of the pump piston, each leading to injection valves 58 on the internal combustion engine. A pressure valve of known design is used in each of the pressure channels 57 and each pressure channel 57 can alternate between the pressure valve and the junction with the guide cylinder through a relief groove 59 which is arranged in the outer surface of the pump piston and is permanently connected to the filling channel 51 the spray breaks are relieved to a constant level.

Finally, a transverse bore 61 branches off from the longitudinal channel 41 and is connected to a control opening 62 on the lateral surface of the part of the pump piston part 7 with a smaller diameter in the bore 22 . This control opening is connected to the control pressure chamber 32 when the pump piston stroke begins, as shown in FIG. 1, and is closed by the end of the control piston 18 on the pump drive side, which serves as the control edge 63, in the course of the subsequent pump piston stroke of size h _v . Only after this preliminary stroke h _v from the bottom dead center of the pump piston can the high-pressure delivery of the pump piston begin.

The fuel injection pump described above works as follows: When the pump piston 4 driven by the means (not shown) performs its suction stroke and the shut-off solenoid valve 53 has opened the filling channel 51 , the pump working space is completely filled with fuel with each suction stroke of the pump piston. The filling opening 50 is connected to the filling channel 51 . During the subsequent discharge stroke of the distributor port 56 comes into communication with one of the pressure channels 57 and connecting the fill port to the charging port is interrupted. When the ring slide 44 is in partial load, the outlet 45 is still closed and the control opening 62 is closed after a stroke h _v in the case of a control piston 18 which is in contact with the adjustment spring 30 after overcoming the start spring 27 . Thereafter, a high pressure can build up in the pump work chamber 25 , which propagates via the longitudinal channel 41 and one of the pressure channels 57 to the injection valve 58 , which opens it and triggers the fuel injection. If the internal combustion engine is in the partial load range, the outlet 45 is opened by the control edge 43 of the ring slide 44 in the course of the subsequent conveying before the annular groove 52 comes into connection with the filling channel 51 . From this point on, the remaining fuel delivered by the pump piston flows into the interior 38 . The injection has ended. However, if the internal combustion engine is in full-load operation, the annular groove 52 comes into connection with the filling channel 51 after a pump piston stroke h _FE and before opening the outlet 45 , which also relieves the pressure on the pump work chamber towards the pressure line 40 and ends the injection. This has the advantage that a constant Vollastförderende or fuel injection end is achieved, and that the annular slide can be shifted 44 more in the direction of the cylinder liner 3 as it would be necessary to adjust the full power injection quantity advantage. In Abregelfall the annular slide must then traverse a initial stroke until with the elimination of the control function of the annular groove is opened earlier 52 of the outlet 45, so that the fuel injection pump in the course of further shifting of the annular slide is regulated 44 against 0th It is advantageously avoided that a pendulum movement of the ring slide, caused by the regulating process of the controller in the regulating point, has an effect on the onset of the regulating and the full load power is fully retained up to the desired regulating point. Hysteresis influences are also switched off.

To generate a starting excess when starting the internal combustion engine the function is as follows:

Before the start, the pressure in the interior 38 is at a very low level, so that the control piston 18 is in contact with the cylinder liner 3 under the influence of the compression spring 27 , since the necessary pressure in the control pressure chamber 32 is missing. So that the control opening 62 is closed by the control piston 18 during the course of the pump piston delivery stroke and also remains closed. Accordingly, an additional starting quantity of fuel per pump piston delivery stroke that exceeds the full-load injection quantity is injected. This quantity accumulates before the full-load injection quantity, so that a quantity-related early adjustment of the start of injection takes place at the start. As the speed begins, pressure builds up in the interior 38 , which then displaces the control piston 18 against the starting spring 27 until it abuts the adjustment spring 30 and keeps the control opening 62 open in the starting position of the pump piston.

The function described above also occurs when no adjustment spring 30 is provided on the control slide 18 . In this case, the control piston runs after the pressure in the control pressure chamber 32 has built up until it contacts the collar 29 . If, however, as shown in FIG. 1, a matching spring is present, it is compressed more with increasing speed in accordance with the pressure in the control pressure chamber 32 until the end face 26 comes into contact with the collar 29 . In the course of this process, the preliminary stroke h _{v increases} so that the effective delivery stroke of the pump piston decreases at full load until the final stroke h _{FE is} reached with increasing speed.

FIG. 2 shows a control diagram in which a pump piston stroke is plotted over the angle of rotation α of the pump piston. The characteristic strokes are also shown. The stroke h _{FE represents} the stroke to the delivery end of the pump piston or to the opening of the pump working chamber 25 via the annular groove 52 . In addition, a stroke h _{s is} recorded which is greater than the end stroke of stroke h _FE and indicates the position of the ring slide in full load position. It can be seen from this that the opening of the outlet 45 through the ring slide is no longer tax effective. Finally, the preliminary stroke h _{v is} plotted, from which the high-pressure delivery from the pump work space begins. From the bottom dead center of the pump piston to the lifting height h _v , the additional starting quantity of the full load quantity, which is delivered between h _v and h _FE , accumulates. The stroke h _v is further increased by compression of the adjustment spring 30 in the sense of a positive adjustment, which is shown in the diagram by various small cross lines, connected with the arrow + AN in the direction of the top dead center OT. If the adjustment spring 30 is missing, this part of the illustration in FIG. 2 is omitted.

In Fig. 3 a variant of the embodiment of FIG. 1 is shown. The compression spring 27 , which is the starting spring in FIG. 1, is omitted here in the case of a fuel injection pump of the same design. A displacement of the control piston 18 with speed-dependent pressure build-up in the control pressure chamber 32 thus takes place only against the spring 30 , as a result of which the preliminary stroke h _{v is} changed. A positive adjustment of the full-load injection quantity is thus achieved, as in the exemplary embodiment according to FIG. 1. To achieve a starting additional quantity of fuel, the control of the maximum delivery stroke or the constant delivery end at stroke h _FE is designed so that the annular groove 52 is assigned a discharge line 64 coming from the guide cylinder 2 , via which the pump working space is relieved when it overlaps with the annular groove 52 can be. The relief line 64 leads into a cylinder 66 which is arranged parallel to the guide cylinder 2 in the housing 1 and opens into the interior 38 on one end face thereof. A starting piston 67 is displaceable in the cylinder 66 and can be brought into contact with a stop 68 on the inside of the pump by a spring 69 acting on its rear side and is displaced away from this stop against the spring 69 with increasing pump interior pressure. In the starting position, the opening of the relief line 64 is closed by the outer surface of the starting piston. It is opened from a certain interior pressure after displacement of the starting piston 67 through a control edge 70 provided thereon to the pump interior 38 . In this way, the control function of the annular groove 52 in connection with the relief line 64 on the guide cylinder 2 is canceled at the start, so that the pump piston conveys fuel beyond the delivery end defined by the stroke h _FE to TDC or until the annular groove 52 in connection with the filling channel 51 is coming. A prerequisite for this is that the ring slide 44 is brought in the direction of the cylinder liner 3 into a starting position in which the outlet 45 is not opened via the pump piston stroke. In this embodiment, the starting additional quantity is advantageously attached to the full-load injection quantity, so that the starting additional quantity does not influence the start of injection. The starting piston 67 and the spring 69 are designed so that they keep the relief bore 64 open during the entire normal operation. A pressure hysteresis on the starting piston can be achieved by designing the pressure level on the starting piston by remaining in the disengaged position by enlarging the area under pressure after lifting from an initial position even at lower pressure than when the pressure triggering the deflection of the starting piston is maintained.

Fig. 4 shows a variant of the embodiment of Fig. 3. In this embodiment, as in the embodiment of Fig. 1 or Fig. 3, the pump piston 4 'in the guide bore 2 of the cylinder liner 3 is displaceable and has the longitudinal channel 41 , the connection to the distribution opening 56 , also advantageously configured as a longitudinal groove, and the filling opening 50 , also designed as a longitudinal groove. On the part 6 of the pump piston which projects into the interior 38 and is larger in diameter, the ring slide 44 can in turn be moved, which controls the outlet 45 of the longitudinal channel with its control edge 43 .

The smaller in diameter part of the pump piston 7 'dips beyond the cylinder liner 3 into the bore 22 of a control piston 18 ' and, together with the plug 24 inserted into the bore 22 from the opposite side, encloses the pump working chamber 25 as in the embodiment according to FIG. 1. The plug lies over the collar 29 on the stop pin 12 and also serves as a base for a compression spring 27 ', which is no longer a starting spring here. The compression spring is supported on a shoulder 71 of the control piston 18 ', which in turn is tightly displaceable in the cylinder 9 . It includes on the side of the closure part 10 now a control pressure chamber 32 ', which is constantly connected to the pump interior 38 via a connecting line 72 analogous to the pressure line 40 according to FIG. 1. On the other side of the control piston, this includes a relief space 33 'together with the cylinder liner 3 . On this side of the control piston 18 'is located on a shoulder 73, the adjustment spring 30 ', which is now supported on the other hand on the end face 60 of the cylinder liner 3 or the cylinder 9 and against which serves as a stop of the control piston 18 'by the maximum adjustment path A. is movable. In this embodiment, the longitudinal channel 41 a transverse bore 61 ', which opens into a control opening 62 ' in the form of an annular groove. This annular groove is assigned a second annular groove 65 which is arranged in the wall of the bore 22 and on the other hand is connected via one or more channels 75 to the control pressure chamber 32 '. This connection serving the relief of the pump work space can also be made to the relief space 33 '. Also one of the annular grooves 65 or 62 'can be omitted and only the openings of the bores 75 and the transverse bore 61 ' can be made. The assignment of the second annular groove 65 to the control opening 62 'is such that in the starting position of the pump piston from bottom dead center, these are initially in register. From a preliminary stroke h _v , the control opening 62 'is then closed by the wall of the bore 22 , so that from this stroke 25 high pressure can be built up in the pump working chamber, as far as the outlet 45 is closed by the ring slide 44 .

In the control diagram according to FIG. 5, a piston stroke curve is again recorded over its angle of rotation α. The stroke h _FE indicates the end of delivery from which the pump working chamber 25 is relieved via the controlled outlet 45 . In the present exemplary embodiment, this end of conveyance is variable depending on the setting of the ring slide. In addition to the full-load injection quantity, the latter also sets the additional starting quantity by being displaced in the direction of the cylinder liner 3 in a known manner. The control diagram in FIG. 5 also shows the preliminary stroke h _v from which the effective delivery stroke of the pump piston begins, so that the fuel injection quantity to be injected results from the difference between the stroke h _FE and the preliminary stroke h _v . Since the control pressure chamber 32 'is subjected to higher pressure with increasing speed, the control piston 18 ' moves accordingly in the direction of the cylinder liner 3 and thus reduces the preliminary stroke h _v . In this way, the actual fuel injection quantity is preceded by an additional adjustment quantity, which increases with increasing engine speed, which ultimately corresponds to a negative adjustment. While the adjustment quantity precedes the basic injection quantity, the start quantity is subordinate to the full-load injection quantity and thus has no influence on the start of injection at the start.

The exemplary embodiment according to FIG. 6 is an alternative embodiment of the embodiment according to FIG. 4. In modification of this, the control of the additional starting quantity is solved differently in FIG. 6. In this case, the annular groove 52 'is provided on the pump piston 4 ''in a manner similar to the exemplary embodiment according to FIG. 3 on the larger-diameter pump piston part 6 ', the annular groove 52 'being in constant communication with the filling opening 50 . About this and the longitudinal channel 41 , the annular groove 52 'is connected to the pump working space 25 . In a region between the ring groove 52 'at the bottom dead center position of the pump piston and the entry of the filling channel 51 into the guide cylinder 2 branches off from the guide cylinder 2, a relief line 76 analogous to the relief line 64 of Fig. 3, which opens into a cylinder 66 in which a starting piston 67 is displaceable. The starting piston is held by a compression spring 69 in abutment against a stop 68 as long as the pressure in the interior 38 is too low to deflect the starting piston from this position. In this position, the relief line 76 is closed and is only opened from a certain interior pressure after the starting piston 67 has been deflected. As in FIG. 3, this means that when the relief line 76 is open, the effective pump piston delivery stroke is ended constantly from a delivery end stroke h _FE even when the ring slide 44 is in the full load position or even the start position, in which positions the outlet 45 only opens after the relief line has been opened 76 is opened. This applies to normal operation. In the case of partial load operation, the pump work space is relieved sooner or later before the stroke h _{FE in} accordance with the ring slide position 44 . At the start, on the other hand, the relief line 76 is completely closed, so that an additional additional amount of fuel can be added as an additional starting amount if the ring slide 44 is in the appropriate position.

In a fifth embodiment of the invention according to FIG. 7, it is a modification of the embodiment according to FIG. 1. Notwithstanding this, the control slide 18 '' is designed, which in turn separates a control pressure chamber 32 on the cylinder liner side from a relief part 33 on the closure part side. The control piston 18 '' consists of an inner sleeve 77 and an outer sleeve 78 which are firmly connected to one another, which can be done for example by electron beam welding. The inner sleeve 77 has the bore 22 according to the embodiment of FIG. 1, in which from one side the smaller diameter part 7 of the pump piston 4 is immersed and from the other side a plug 24 ', which thus with the pump piston, the pump working space 25 in which includes bore 22 . The plug 24 'in turn has the collar 29 at the end projecting from the bore 22 and there the spring plate 28 , which serves to abut the compression spring 27 formed as a starting spring, which on the other hand is supported on a shoulder of the outer sleeve 78 . The outer sleeve 78 slides as the control piston 18 of FIG. 1 tightly in the cylinder 9 and closes together with the inner sleeve 77 and the cylinder liner 3 to the control pressure chamber 32 a, which via the longitudinal groove 46 to the filling channel 51 and the pressure line 40 and the interior 38 is connected. Due to the pressure prevailing in the control pressure chamber 32 , the control piston 18 '' is moved in the direction of the closure part 10 until this control piston comes with its end face 26 ', which is assigned to the inner sleeve 77 in the example shown, to rest on the collar 29 .

An annular space 80 is formed between the inner sleeve 77 and the outer sleeve 78 and serves as a connecting channel between a first radial bore 81 and a second radial bore 82 through the wall of the inner sleeve 77 . Instead of a first or second radial bore, several of them can also be provided, which then each lie in a common radial plane with the pump piston axis. The first radial bore opens via a first opening 83 in the bore 22 and the second radial bore through a second opening 84 into the bore 22nd With the first pump piston-side opening 83 , a control opening 62 '', in the example shown designed as an annular groove in the outer surface of the pump piston, works together. The control opening 62 '' is connected via a transverse bore 61 '' to the longitudinal channel 41 and comes after a pump piston stroke h _FE determining the delivery end after the bottom dead center of the pump piston in connection with the first opening 83 . When overlapping with the first opening 83 , fuel can pass from the pump working space into the annular space 80 , from which it passes via the second radial bore 82 and the second opening 84 into an outer annular groove 85 on the stopper 24 '. The outer annular groove 85 is connected to an outflow channel, consisting of a transverse bore 86 and a further bore 87 extending therefrom in the stopper and an annular groove 88 'provided on the stopper 24 , into which the bore 87 opens and which directly adjoins the collar 29 . The fuel reaching there can then escape via throttle openings 89 between the end face 26 'of the inner sleeve 77 and the collar 29 of the plug into the relief space 33 . The throttle opening can of course also be arranged somewhere else in the outflow channel, but can be manufactured cheaply in the above arrangement. The connection between the second opening 84 and the outer annular groove 85 is only as long as the control piston 18 '' in the end position shown is in contact with the collar 29 . This can only occur if the pressure in the control pressure chamber 32 is large enough to overcome the starting spring 27 .

While the preliminary stroke was controlled by the control edge 63 in connection with the control opening 62 in the embodiment according to FIG. 1, which was also the case in the embodiment according to FIGS. 2, 4 and 6, here the control opening 62 '' controls in connection with the first Opening 83 the end of conveyance. In the above-described pump, this is set to a constant stroke h _FE after the start spring 27 has been overcome. At the start, however, and low pressure in the control pressure chamber 32 , the control piston 18 '' is displaced towards the cylinder liner 3 so that the second opening 84 is no longer in register with the outer annular groove 85 , but is closed by the plug 24 '. Now reaches the control opening 62 '', the first opening 83 , the fuel can still not escape. The high-pressure fuel delivery is therefore continued and an excessive start quantity is injected. This follows the full-load injection quantity. After the conveying end is fixed in this way, there is no need to adjust the conveying end with the aid of a conveying end groove according to the annular groove 52 in the exemplary embodiment according to FIG. 1 in connection with the filling channel 51 . Nevertheless, in the exemplary embodiment according to FIG. 7, an annular groove 90 is provided in the pump piston part 7 of the pump piston which is larger in diameter and is in constant communication with the filling opening 50 . In this case, however, the annular groove 90 is located upstream of the filling opening 50 towards the control piston side and is initially in connection with the filling channel 51 when the pump piston begins to lift. The overlap is then removed from a preliminary stroke h _v , so that from this point high-pressure delivery can take place from the pump work chamber 25 .

Based on the above-described embodiment according to FIG. 7, an adjustment can now also be provided analogously to the embodiment according to FIG. 1 by arranging an adjustment spring 30 between the collar 29 and a shoulder 31 as in FIG. 1. The shoulder 31 is the end face of the outer sleeve 78 . In such a case, a non-throttling outflow groove is provided in the end face 26 'of the control piston instead of the throttle opening 89 . The control piston 18 '' comes after overcoming the starting spring 27 in contact with the adjustment spring 30th In this position there is already a connection between the first opening 83 and the outer annular groove 85 on the plug 24 '. While in this starting position the control opening 62 'comes relatively early in connection with the first opening 83 , with increasing pressure in the control pressure chamber 32 and displacement of the control piston 18 ''against the adjustment spring 30 of the pump work chamber is relieved to an ever later pump piston stroke. This results in an increasing full-load injection quantity with increasing engine speed, which follows in the direction of top dead center TDC at the end of the main injection. This corresponds to a negative adjustment. The relationship is again shown in a control diagram shown in FIG. 8. There, a pump piston stroke is plotted over the angle of rotation α and the preliminary stroke h _v , up to which no high-pressure delivery takes place, and on which the fuel injection is then carried out up to the stroke h _FE . With the arrow -AN the adjustment displacement of the control piston 18 '' is indicated. The strokes correspond to the fuel injection quantities. The fuel injection quantity control in the partial load area is carried out with the aid of the ring slide 44 , as in the previous exemplary embodiments. The throttle opening 89 in the end face 26 'in the first-described variant of FIG. 7 replaces an adjustment by moving the control piston 18 ''against the adjustment spring 30th Since the outflow quantity via the throttle opening takes place in a shorter time with increasing speed, the discharge over the outflow quantity decreases with increasing speed, which corresponds to an increasing fuel injection quantity with increasing speed and thus also a negative adjustment. In all embodiments, the starting quantity, insofar as it is realized with the aid of the control piston 18 or 18 '', can be varied by adjusting the stop bolt 12 . All in all, with the same basic construction of the pump and variation of control openings in the pump piston or variation of the control piston, the fuel injection pump can be adapted to the various requirements of different internal combustion engines. There is the advantage that only a few parts need to be replaced here that complement the otherwise identical fuel injection pump structure in the modular system. Starting quantity deliveries can be implemented before or after the full load quantity and, if desired, an automatic advance adjustment of the fuel injection can be achieved. Both positive and negative alignments can be achieved. By assigning the control of the advance stroke to the control piston, a quantity drift can be avoided by setting the piston or by wear on the pump piston drive side or wear on the controller parts. This applies in particular to the configurations according to FIGS. 1, 3, 4 and 6. A quantity drift, in particular of the full-load injection quantity, can compensate for wear of the controller parts by specifying a constant delivery end after the stroke h _FE . In connection with the control of the advance stroke by the control piston, setting of the pump piston can also be compensated for.

Claims (13)

1.Fuel injection pump for internal combustion engines with a reciprocating and at the same time rotating drive, designed as a stepped piston and with the larger diameter, serving as distributor piston part ( 6 ) in a guide cylinder ( 2 ) guided pump piston ( 4 ), on the smaller in diameter Stepped piston part ( 7 ) at the end projecting from the guide cylinder ( 2 ) is displaceably arranged a control slide arrangement ( 18 ) which has a bore ( 22 ) into which the pump piston ( 4 ) from one side and a plug ( 24 ) from the immerse another side including a pump work chamber ( 25 ), which stopper ( 24 ) on its outside of the bore ( 22 ) is in contact with an adjustable stop pin ( 12 ) which is coaxial to the pump piston through a closure part ( 10 ) of the fuel injection pump housing ( 1 ) is adjustable ver and the control slide device ( 18 ) Ch has an adjusting piston part, which is displaceable in a one hand towards the guide cylinder ( 2 ) and on the other hand through the closure part ( 10 ) on both sides closed cylinder ( 9 ) by a stationary supporting spring ( 27 , 30 ), the displacement path of the control piston can be limited by at least one stop ( 29 ) and the spring ( 27 , 30 ) is arranged in a relief chamber ( 33 ) enclosed by the adjusting piston part in the cylinder ( 9 ), which is relieved of pressure via a relief channel ( 34 ), whereas the relief chamber ( 33 ) facing away from the control piston partly in the cylinder ( 9 ) delimits a control pressure chamber ( 32 ) which is connected via a pressure line ( 40 , 72 ) to a pressure source ( 38 ) which has a speed-dependent pressure and to one in the pump piston ( 4 ) of its outgoing longitudinal channel ( 41 ) which delimits the pump working chamber ( 25 ) and which has a control opening ( 62 ) in the jacket surface he of the pump piston ( 4 ) is connected and a connection of the control opening ( 62 ) to a space which relieves the pump work space ( 25 ) can be controlled by a control edge ( 63 , 65 , 83 ) on the control slide device ( 18 ), which longitudinal channel ( 41 ) is furthermore controllable Via at least one filling opening ( 50 ) opening in the lateral surface of the part ( 6 ) of the pump piston ( 4 ) serving as distributor in the region of the guide cylinder ( 2 ) and at least one filling channel ( 51 ) opening into the guide cylinder ( 2 ) from a fuel supply source for supply of fuel can be connected during the suction stroke of the pump piston and which has a distributor opening ( 56 ) in the jacket surface of the pump piston in the area of the guide cylinder ( 2 ) during the pressure stroke of the pump piston, each with one of several nozzles distributed around the pump piston and discharging with injection points ( 58 ) in the internal combustion engine connectable pressure channels ( 57 ) connected n, characterized in that the control slide arrangement is formed with an actuating piston part as a control piston ( 18 ), which can be pushed tightly in the cylinder ( 9 ) by the speed-dependent pressure against the spring designed as a compensating spring ( 30 ) and between which and the stopper ( 24 ) the adjustment spring ( 30 ) or an additional spring ( 27 ) is clamped in that the filling channel ( 51 ) during operation of the fuel injection pump is unthrottled during the suction stroke of the pump piston ( 4 ) with the fuel supply source, which pumps through a fuel-filled interior ( 38 ) of the fuel injection is formed, is connected that further the pump piston emerges on the drive side from the guide bore ( 2 ) into the interior ( 38 ), there on its lateral surface has a ring slide ( 44 ) adjustable from a fuel injection regulator ( 47 ), which has a control edge ( 43 ) controls an outlet ( 45 ) of the longitudinal channel ( 41 ) into the interior ( 38 ) and that the effective point of opening or closing the pump work space via the control opening ( 62 ) and the control edge ( 63 ) controlling this on the control piston ( 18 ) in the control pressure space ( 32 ) or end relief space ( 33 ) as relief spaces for additional control of the end or Beginning of the high-pressure delivery of fuel by the pump piston after starting in operation of the fuel injection pump to adjust the fuel injection quantity depending on the speed can be changed. 2. Fuel injection pump according to claim 1, characterized in that the control pressure chamber ( 32 ) on the guide cylinder side of the cylinder ( 9 ) and the adjusting spring ( 30 ) between the control piston ( 18 ) and the stopper serving as a stop for the control piston ( 24 ) supports ( Fig. 1, 3, 7). 3. Fuel injection pump according to claim 2, characterized in that a starting spring ( 27 ) between the control piston ( 18 ) and plug ( 24 ) is arranged as an additional spring ( Fig. 1 and 7). 4. Fuel injection pump according to claim 1, characterized in that the relief chamber ( 33 ) on the guide cylinder side of the control piston ( 18 ') and the control pressure chamber ( 32 ') is on the closure part side of the control piston and has the additional spring ( 27 '), which is clamped between the control piston ( 18 ') and plug ( 24 ), the end face ( 60 ) of the cylinder ( 9 ) on the guide cylinder side serving as a stop for the control piston ( 18 ') ( Fig. 4). 5. Fuel injection pump according to one of the preceding claims 2 to 4, characterized in that the control opening ( 62 , 62 ') on contact of the control piston ( 18 , 18 ') on the not yet compressed adjusting spring ( 30 , 30 ') through the control edge ( 63 , 65 ) on the control piston ( 18 , 18 ') is open and is closed after a preliminary stroke (h _v ) of the pump piston, the preliminary stroke (h _v ) depending on the speed-dependent pressure in the control pressure chamber ( 32 , 32 ') by compression of the Adjustment spring ( 30 , 30 ') is changed ( Fig. 1, 3 and 4). 6. Fuel injection pump according to claim 5, characterized in that the control edge ( 65 ) on the control piston ( 18 ') is formed by the boundary edge of the opening of a through the wall of the control piston channel ( 75 ) ( Fig. 4). 7. Fuel injection pump according to one of the preceding claims, characterized in that with the longitudinal channel ( 41 ) an outlet opening ( 52 , 52 ') is connected to the outer surface of the pump piston, which from a pump piston stroke (h _FE ) to limit the delivery stroke of the pump piston effective in conveying is connected to a relief line ( 40 , 64 , 76 ) leading from the guide cylinder ( 2 ) to a relief space ( FIGS. 1, 3 and 6). 8. Fuel injection pump according to claim 7, characterized in that the outlet opening is an annular groove ( 52 , 52 ') in the outer surface of the pump piston. 9. Fuel injection pump according to one of claims 7 or 8, characterized in that the relief line ( 64 , 76 ) is opened by a piston ( 67 ) which can be actuated as a function of a speed-controlled pressure in the fuel-filled space ( 38 ) after the start of the internal combustion engine ( Fig . 3 and 6). 10. Fuel injection pump according to claim 2, characterized in that a starting spring ( 27 ) is clamped between the control piston ( 18 '') and stopper ( 24 ') as an additional spring for the adjustment spring ( 30 ) and the control piston ( 18 '') as a limiting edge has first opening ( 83 ) in the lateral surface of the bore ( 22 ) and the first opening ( 83 ) is connected via a connecting channel ( 80 ) running in the control piston to a second opening ( 84 ) in the lateral surface of the bore ( 22 ), which after Overcoming the starting spring ( 27 ) can be connected to an outflow channel ( 85, 86, 87, 88 ) leading from the lateral surface of the stopper ( 24 ') to a relief chamber ( 33 ), the opening point of the control opening ( 62 '') through the first opening ( 83 ) after a pump piston stroke (h _FE ) determines the delivery end of the pump piston and the deflection of the adjustment spring ( 30 ) after overcoming the start spring ( 27 ) determines the delivery Rende is shifted in particular in the direction of an enlarged pump piston stroke (h _FE ) effective for conveying ( Fig. 7). 11. Fuel injection pump according to claim 10, characterized in that the matching spring ( 30 ) and the starting spring ( 27 ) are supported on a collar ( 29 ) or spring plate ( 28 ) of the stopper ( 24 ') ( Fig. 7). 12. Fuel injection pump according to one of claims 10 and 11, characterized in that a throttle ( 89 ) is provided in the course of the outflow channel ( 85 , 86 , 87 , 88 ) ( Fig. 7). 13. Fuel injection pump according to one of claims 10 to 12, characterized in that the connecting channel ( 80 ) is designed as an annular space between an outer sleeve ( 78 ) and an inner sleeve ( 77 ) which are joined together and the control piston ( 18 '' ) is included ( Fig. 7).