DE1062063B

DE1062063B - Fuel injection pump for multi-cylinder internal combustion engines

Info

Publication number: DE1062063B
Application number: DEB48518A
Authority: DE
Inventors: Berthold Oxenfart
Original assignee: Robert Bosch GmbH
Current assignee: Robert Bosch GmbH
Priority date: 1958-04-11
Filing date: 1958-04-11
Publication date: 1959-07-23

Description

£JLk£ JLk

Die Erfindung betrifft eine Kraftstoffeinspritzpumpe mit einem einzigen Pumpenarbeitsraum sowie einem Verteiler zur Versorgung einer mehrzylindrigen Brennkraftmaschine und mit mindestens einem radial beweglichen, durch einen Radialnocken angetriebenen Pumpenkolben, dessen zugehöriger Pumpenzylinder in einem mit dem umlaufenden Verteilerglied sich drehenden Pumpenteil angeordnet ist.The invention relates to a fuel injection pump with a single pump working chamber as well a distributor for supplying a multi-cylinder internal combustion engine and with at least one radial movable pump piston driven by a radial cam, its associated pump cylinder is arranged in a rotating with the rotating distributor member pump part.

Bei bekannten Einspritzpumpen dieser Art wird zum Zweck der Verstellung des Förderbeginns der Einspritzpumpe der normalerweise feststehende Teil des Nockenantriebs um den Winkel der gewünschten Förderbeginnverstellung verdreht. Diese Art der Förderbeginnverstellung hat jedoch den Nachteil, daß das Verteilerglied die Drehbewegung des Nockenantriebteils nicht mitmacht und deshalb die Steuerkanäle des Verteilergliedes eine unzulässige Drosselung erfahren können. Dies wirkt sich insbesondere dann ungünstig aus, wenn das Verteilerglied, wie es bei dieser Pumpenbauart üblich ist, auch den Einlaßkanal zum Pumpenarbeitsraum steuert. Es ist ferner bekannt, daß Verstelleinrichtungen für den Förderbeginn, die mit der Antriebswelle der Pumpe zusammengebaut sind, diesen Nachteil vermeiden. Aufgabe der Erfindung ist es nun, die eingangs beschriebene Pumpenbauart mit einer derartigen Verstelleinrichtung so zu vereinigen, daß sich eine Pumpe mit möglichst geringen Außenabmessungen und einfachem Innenaufbau ergibt.In known injection pumps of this type, for the purpose of adjusting the start of delivery of the Injection pump the normally fixed part of the cam drive to the angle of the desired Start of delivery adjustment twisted. However, this type of delivery start adjustment has the disadvantage that the distributor member does not take part in the rotary movement of the cam drive part and therefore the control channels the distribution link can experience an impermissible throttling. This affects in particular then unfavorable when the distributor member, as is usual with this type of pump, also the inlet channel controls to the pump work area. It is also known that adjusting devices for the start of delivery, which are assembled with the drive shaft of the pump avoid this disadvantage. task of the invention is now the type of pump described at the beginning with such an adjusting device to unite in such a way that a pump with the smallest possible external dimensions and simple Internal structure results.

Diese Aufgabe wird gemäß der Erfindung im wesentlichen dadurch gelöst, daß der dem Pumpenzylinder enthaltende Pumpenteil mit einem Mitnehmer gekuppelt ist, in den ein den Mitnehmer mit der Antriebswelle kuppelndes Zwischenglied eingreift, das gleichachsig zur Antriebswelle verschiebbar ist und bei seiner Verschiebebewegung den Mitnehmer gegenüber der Antriebswelle drehverstellt.This object is achieved according to the invention essentially in that the pump cylinder containing pump part is coupled to a driver, in which a driver with the Drive shaft coupling intermediate member engages, which is coaxially displaceable to the drive shaft and during its displacement movement, the driver rotates relative to the drive shaft.

In der Zeichnung ist ein Ausführungsbeispiel des Gegenstandes der Erfindung dargestellt, und zwar zeigtIn the drawing, an embodiment of the subject matter of the invention is shown, namely shows

Fig. 1 einen Längsschnitt durch die Einspritzpumpe nach Linie I-I in Fig. 2 mit einer schematischen Darstellung der Kraftstoffzufuhranlage,1 shows a longitudinal section through the injection pump along line I-I in FIG. 2 with a schematic representation the fuel supply system,

Fig. 2 einen Schnitt nach Linie H-II in Fig. 1 und Fig. 3 einen Schnitt nach Linie III-III in Fig. 2.FIG. 2 shows a section along line H-II in FIG. 1 and FIG. 3 shows a section along line III-III in FIG. 2.

In einem Pumpengehäuse 1 ist eine Antriebswelle 2 gelagert, deren innerer Endabschnitt 3 als Zylinder für eine kolbenartige Hülse 4 ausgebildet ist. Am Boden der Hülse 4 greift einerseits das untere Ende einer Schraubendruckfeder 5 und andererseits ein im Zylinderraum 6 herrschender Flüssigkeitsdruck an. Der Raum 6 ist über eine Ouerbohrung 7 mit einer Ringnut 8 im Pumpengehäuse 1 verbunden. In die Ringnut mündet ein Einlaßkanal 9.A drive shaft 2 is mounted in a pump housing 1, the inner end section 3 of which is a cylinder is designed for a piston-like sleeve 4. On the one hand, the lower end engages at the bottom of the sleeve 4 a helical compression spring 5 and, on the other hand, a fluid pressure prevailing in the cylinder space 6. The space 6 is connected to an annular groove 8 in the pump housing 1 via an outer bore 7. In the An inlet channel 9 opens into the annular groove.

Kraftstoffeinspritzpumpe
für mehrzylindrige BrennkraftmaschinenFuel injection pump
for multi-cylinder internal combustion engines

Anmelder:Applicant:

Robert Bosch G.m.b.H.,
Stuttgart-W, Breitscheidstr. 4Robert Bosch GMBH,
Stuttgart-W, Breitscheidstr. 4th

Berthold Oxenfart, Stuttgart,
ist als Erfinder genannt wordenBerthold Oxenfart, Stuttgart,
has been named as the inventor

Eine durch die nicht dargestellte Brennkraftmaschine angetriebene Zubringerpumpe 11 saugt Kraftstoff aus einem Behälter 12 an' und fördert diesen über ein Filter 13 zum Einlaßkanal 9 sowie zu einer Einlaßöffnung 15 in einem auf das Pumpengehäuse 1 aufgesetzten Pumpenkörper 16. An das Filter 13 ist ein als Drossel wirkendes Überströmventil 17 angeschlossen, über das die durch die Pumpe 11 im Überschuß geförderte Kraftstoffmenge zum Behälter 12 abfließen kann.A feed pump 11 driven by the internal combustion engine (not shown) sucks Fuel from a container 12 to 'and conveys this through a filter 13 to the inlet channel 9 and to an inlet opening 15 in a pump body 16 placed on the pump housing 1 Filter 13 is connected to an overflow valve 17 acting as a throttle, via which the pump 11 in excess of the amount of fuel delivered to the container 12 can flow off.

Der Wellenabschnitt 3 und ie Hülse 4 haben Längsschlitze, durch die einei Führungsplatte 18 quer hindurchsticht. An dieser Platte stützt sich das obere Ende der Feder 5 ab. Die Enden der Führungsplatte selbst werden dabei gegen die Unterseite des Bodens 19 des topfartigen Endäbschnittes 20 der Antriebswelle gedrückt. In dem Abschnitt 20, dessen Wandung an zwei diametral zueinander liegenden Stellen unterbrochen ist, ist ein Mitnehmer 21 gelagert, der ein mehrgängiges Innensteilgewinde 22 hat, in welches ein entsprechendes Außengewinde 23 der Hülse 4 eingreift. The shaft section 3 and the sleeve 4 have longitudinal slots through which a guide plate 18 pierces transversely. The upper end of the spring 5 is supported on this plate. The ends of the guide plate themselves are thereby against the underside of the bottom 19 of the pot-like Endäbschnittes 20 of the drive shaft pressed. In the section 20, the wall of which is interrupted at two diametrically opposite points is, a driver 21 is mounted, which has a multiple internal partial thread 22, in which a corresponding external thread 23 of the sleeve 4 engages.

In einer Quernut des Mitnehmers 21 sind Stößel 25 geführt, deren Rollen 26 -mit einem im Gehäuse 1 fest angeordneten Innennockenring 27 zusammenarbeiten. In die Führungsnut für die Stößel 25 greifen außerdem radiale Ansätze 30 eines im Pumpenkörper 16 gelagerten Verteilergliedes 31 ein. Längs durch diese Ansätze 30 hindurch erstreckt sich eine Zylinderbohrung 32, in der zwei Pumpenkolben 33 geführt sind, die jeweils mit ihren äußeren. Enden an einem der Stößel 25 anschlagen. Zwischen den beiden Pumpenkolben 33 befindet sich ein Pumpenarbeitsraum 34, von dem ein das Verteilerstück 31 axial durchsetzender Längskanal 35 ausgeht. Dieser Kanal ist oben durch einen Stopfen 36 abgeschlossen.In a transverse groove of the driver 21, plungers 25 are guided, the rollers 26 of which are fixed with one in the housing 1 arranged inner cam ring 27 work together. In addition, engage in the guide groove for the plunger 25 radial lugs 30 of a distributor member 31 mounted in the pump body 16. Lengthways through this A cylinder bore 32 extends through lugs 30, in which two pump pistons 33 are guided are each with their outer. Hit the ends on one of the plungers 25. Between the two Pump piston 33 is a pump working chamber 34, one of which is the distributor piece 31 axially penetrating longitudinal channel 35 goes out. This channel is closed at the top by a plug 36.

Das Verteilerglied 31 ist im Pumpenkörper 16 gelagert. Die Lagerbohrung für das Verteilerglied istThe distributor member 31 is mounted in the pump body 16. The bearing hole for the distributor link is

909 578/120909 578/120

Claims

closed by a plug 39 which presses against the plug 36 from above via a spring 40 and a ball 41, so that the distributor member 31 is supported with its pin-shaped lower end 43 on the guide plate 18. The tappets 25 are guided in the direction of the pump axis on the one hand by the driver 21 and on the other hand by a ring 45 embedded in the pot-like section 20. An inlet bore 46 extends from the inlet opening 15 of the pump body 16 and contains an adjustable throttle member 47 and opens into the bearing bore for the distributor member 31. Four inlet channels 48 in the distributor member 31, one of which is indicated by dash-dotted lines in FIG. An outlet channel 49 in the distributor member 31 cooperates with four outlet channels 50, only one of which is also shown. Each of the outlet channels 50 opens into an outlet opening 51. Lines (not shown) lead to the cylinders of the internal combustion engine at the outlet openings. The mode of operation of the pump is as follows: When the drive shaft 2 rotates, the sleeve 4 is rotated along with the guide plate 18. The sleeve transmits its rotational movement via the coarse thread connection 22, 23 to the driver 21, which takes the plunger 25 and the distributor member 31 with it. The rollers 26 and their plungers 25 follow the cam track of the cam ring 27. The inward movement of the plunger and thus also the pump piston 33 is inevitably carried out by the cam track, while the outward movement of the piston and plunger is positively caused by the fuel that the feed pump 11 in the pump working space 34 presses. The fuel flows from the inlet opening 15 through the inlet bore 46, one of the inlet channels 48 and the longitudinal channel 35 into the pump working chamber 34. During the pressure stroke of the pump piston 33, the fuel is released from the pump working chamber 34 through the channel 35, the outlet channel 49 and one of the channels 50 conveyed to the outlet opening 51. The pressure of the feed pump 11, which changes as a function of the speed under the action of the throttle valve 17, is also effective in the cylinder space 6 contained in the drive shaft. If the speed of the internal combustion engine and thus the speed of the feed pump 11 increases, the pressure in the space 6 also increases. As a result, the sleeve 4 is displaced against the force of the spring 5. The high-helix thread connection 22, 23 causes a rotation of the driver 21 and the distributor member 31 with respect to the drive shaft 2. This rotation causes an earlier start of delivery of the injection pump with respect to the drive shaft 2. When the engine speed drops, the pressure in chamber 6 falls, and the Sleeve 4 is moved by spring 5. The start of delivery of the injection pump is shifted back. The distributor member and the driver can also form one piece. P A T ENTA X bl'liCCHE:

1. Fuel injection pump with a single pump working space and a distributor for Supply of a multi-cylinder internal combustion engine and at least one radially movable, pump piston driven by a radial cam, its associated pump cylinder is arranged in a pump part rotating with the rotating distributor member, characterized in that that the pump part containing the pump cylinder is coupled to a driver in which the driver with the drive shaft engaging coupling intermediate member which is coaxially displaceable to the drive shaft and during its displacement movement, the driver is rotatably adjusted with respect to the drive shaft.

2. Fuel injection pump according to claim 1, characterized in that the intermediate member on the one hand under the force of a spring and on the other hand under a speed-dependent function changing fluid pressure.

3. Fuel injection pump according to claim 2, characterized in that the intermediate member is coupled to the driver via a coarse thread and the intermediate member designed as a piston guided in the drive shaft serving as a cylinder and with this through an intermediate member and the shaft is coupled transversely penetrating guide plate on which the on the intermediate member supports the spring acting.

4. Fuel injection pump according to one of the preceding claims, characterized in that that the driver for guiding a radially movable drive plunger for the pump piston serves.

5. Fuel injection pump according to one of claims 1 to 4, characterized in that the driver and the distributor member form one piece.

Considered publications:
U.S. Patents Nos. 2,372,180, 2,372,559,
446 497.

Legacy Patents Considered:
German Patent No. 1 035 970.

1 sheet of drawings