GB2211959A

GB2211959A - Mechanical injection pump governor

Info

Publication number: GB2211959A
Application number: GB8825220A
Authority: GB
Inventors: Wendelin Kluegl
Original assignee: Daimler Benz AG
Current assignee: Daimler Benz AG
Priority date: 1987-10-30
Filing date: 1988-10-27
Publication date: 1989-07-12
Anticipated expiration: 2008-10-27
Also published as: FR2622635B1; GB2211959B; GB8825220D0; IT8822105A0; IT1227112B; DE3736781C2; FR2622635A1; DE3736781A1

Description

1 t -11 Mechanical injection pump governor 2211959 The invention relates

to a mechanical injection pump governor in an air- compressing injection-type internal combustion engine.

German Offenlegungsschrift 35 23 095 disclosed an injection pump governor in which the centrifugal weight device acts via a sleeve on a spring capsule which triggers the positive adjustment. What the positive adjustment achieves is that the internal combustion engine on the full load curve receives largely the correct injected quantity. Before commencement of the adjustment which acts only within a certain area of the uncontrolled range, the centrifugal weights of the centrifugal weight device have overridden the idling control spring and thrust spring by way of the sleeve and a guide lever. At the same time the control rod of the injection pump is adjusted via the reversing lever and control arm.

With injection pump governors of the above type it has been found that the injected quantity on the full-load curve is still not matched to the optimum requirement of the internal combustion engine.

The present invention seeks to take measures on a mechanical injection pump governor at little additional expense, which measures make possible a full-load characteristic adapted to the characteristic of the internal combustion engine in the remaining range of the control path performance characteristics.

According to the present invention there is provided a mechanical injection pump governor in an air-compressing injection-type internal combustion engine, comprising a centrifugal weight device which, in operation generates centrifugal forces, which are transmitted through a sleeve and an intermediate lever in the form of a rocking lever on a control arm, which control arm is connected to a control rod of the injection pump, and said centrifugal forces are also transmitted to successively activated spring capsules which are adapted to provide respectively for the negative and positive adjustment of the pump, and further comprising 2 a reversing lever and also a load-dependent floating lever regidly connected to a steering arm, wherein the reversing lever is load- dependent and pivotable, the axis of rotation of the rocking lever is in the reversing lever, and the end of the rocking lever, which is remote from the spring capsule, for negative adjustment is rotatably mounted on the control arm.

The negative adjustment on the full-load curve in the lower speed range results in a desired increase in the control path characteristic which is better used to feed the internal combustion engine and with which a positive influence is exerted with regard to the reduction of the of smoke development. The special integration negative adjustment also has the advantage that the mainly conventional attachment of an atmospheric pressure-dependent full-load stop to a mechanical speed governor still has no active influence on the negative adjustment.

Preferably the spring capsule consists of an articulated head and a shaft which is guided so as to be longitudinall-y displaceable in a guide bush connected to the sleeve in opposition to a pretensioning spring.

Preferably the articulated head bearing bolt which is provided at articulated head as bearings for the reversing guide lever, which are in the form of a double Preferably the guide bush bears a cooperating part on which the sleeve is penetrated by a both ends of the lever and a lever.

fixed sleeve rotatably mounted on the guide bush is supported via a needle bearing.

Preferably the shaft of the articulated head has shaft components with different sized diameters, of which the larger shaft component is exposed and, together with the front side of the guide bush, defines the path of negative adjustment.

Preferably th.e pretensioning spring is supported at one end on the articulated head and, at the other end, on a shoulder of the guide bush.

Preferably the intermediate lever is in the form of a rocking lever having a bearing bolt which i 1 -4 s rigidl- 3 k, connected to this lever and mounted in the reversing lever.

Preferably there is arranged at the free end of the bearing bolt a play compensating spring which is attached to this bolt and supported on the reversing lever and presses the intermediate lever without pla.,y against the sleeve cooperating part.

Preferably the upper free end of the intermediate lever which is remote from the sleeve cooperating part has a bearing bolt on which the control arm is rotatably mounted.

The invention will now be described by way of example, with reference to the accompanying drawings, in which:

Fig. 1 shows a functional diagram of the mechanical injection pump governor having a negative adjustment means, Fig. 2 shows a characteristic diagram which has the control path characteristic with negative adjustment and in which the control path is indicated by RW and the speed by n, Fig. 3 shows a longitudinal section through the lower part of the injection pump governor having a centrifugal weight device and negative adjustment means, Fig. 4 shows a plan view of the negative adjustment means and the intermediate lever, Fig. 5 shows the intermediate lever which is mounted in front of the negative adjustment means and rotatably connected to the control arm, and Fig. 6 shows a front view of the negative adjustment means and the intermediate lever.

A mechanical injection pump governor 1 diagrammatically in Fig. 1, having a centrifugal weight device 2, and a spring capsule 3 for negative adjustment actively connected to this device and a second capsule 4 for positive adjustment, contains a governor body having a power unit and a controlling unit. In the case of the power unit force is transmitted, starting from the centrifugal weights 5, via a sleeve 6, the spring capsule 3 and a guide lever 7 to an idling control spring 6 and a thrust spring 9, and also via the spring capsule 4 and a tension lever 10 to a control spring 4 In contrast, the load input in the case of controlling unit is effected from the floating lever 12 a steering arm 13 and a reversing lever 14 to a control and, via a shackle 16 with a compensating spring 17, the control rod 18 of the injection pump.

the via arm to The spring capsule 3, which cooperates with the centrifugal weight device 2 in the governor body and acts as an auxiliary part of the second spring capsule 4, consists as shown in Fig. 3 - of a guide bush 19 connected to the sleeve 6, of an articulated head 20 with a shaft 21, of which the shaft component 21a designed with a smaller diameter is mounted so as to be longitudinally displaceable in the guide bush 19, whereas the shaft component 21b designed with the larger diameter lies outside the guide bush 19. A pretensioning spring 22 is supported on the articulated head 20 and on a shoulder 23 of the guide- bush 19 and creates a specific distance "a" between the shaft component 21b and the guide bush 19 when the governor is in the starting position. This distance corresponds to the distance of negative adjustment.

The sleeve 6 is rotatably mounted on the guide bush 19 and supported via a needle bearing 24 on a sleeve cooperating part 25 which is arranged rigidly on the guide bush 19.

The sleeve-shaped articulated head 20, which lies at right angles to the shaft 21 according to Fig. 4, is penetrated by a bearing bolt 26 which bears on both sides of the articulated head 20 double levers, the outer one of which forms the reversing lever 14 and the inner one of which forms the guide lever 7. A sheet metal part 27 for securing the bearing bolt is situated at the free end of the bearing bolt 26.

Arranged next to the spring capsule 3 according to Figs. 4 and 6 is an intermediate lever 28 which is in the form of a rocking lever and of which the bearing bolt 29, connected rigidly to this lever extending via the spring capsule 3, is mounted in the reversing lever (Figs. 1,6). The S-shaped intermediate lever 28 (Fig. 4) is applied without play at 1 1 e its lower free end by the spring force of a play compensating spring 30 which is supported as a coil spring at one end on the bearing bolt 29 and at the other end on the reversing lever 14, whereas the upper free end of the intermediate lever 28 has a short bearing bolt 31 on which the control arm 15 is rotatably mounted.

The design and. arrangement of the spring capsule 3 results in the advantage that the spring forces are transmitted centrally through the centre of the sleeve 6 whereby hysteresis can be minimized.

The operating point, the operating end and the increase in negative adjustment "nA" (Fig. 2) can be set precisely by inserting , discs between the pretensioning spring and the articulated head 20.

Function of the negative adjustment means:

The centrifugal weights 5 firstly override the idling control and thrust springs 8,9 via the sleeve 6 and guide lever 7, then they counteract the pretensioning spring 22 of the spring capsule 3 upon further increase in speed. The pretensioning spring 22 is overridden. This operation results in a negative adjustment "nA" on the full load curve "VL". The positive adjustment "pA" takes place only after a stop "x" following the end of the negative adjustment operation (see Fig. 2). Positive and negative adjustments operate independently of one another.

6

Claims

CLAIMS:

centrifugal 1. Mechanical injection pump governor in an air-compressing injection- type internal combustion engine, comprising a weight device which, in operation generates centrifugal forces, which are transmitted through a sleeve and an intermediate lever in the form of a rocking lever on a control arm, which control arm is connected to a control rod of the injection pump, and said centrifugal forces are also transmitted to successively activated spring capsules which are adapted to provide respectivel"v for the negative and positive adjustment of the pump, and further comprising a reversing lever and also a load-dependent floating le.\.-er regidly connected to a steering arm, wherein the reversing lever is load-dependent and pivotable, the axis of rotation of the rocking lever is in the reversing lever, and the end of the rocking lever, which is remote from the spring capsule, for negative adjustment is rotatably mounted on the control arm.

2. Injection pump governor the spring capsule consists of Ll,uided according to claim 1, wherein an articulated head and a shaft which is so as to be longitudinally displaceable in a guide bush connected to the sleeve in opposition to a pretensioning spring.

3. Injection pump governor according to claims 1 and 2, wherein the articulated head is penetrated by a bearing bolt which is provided at both ends of the articulated head as bearings for the reversing lever and guide lever which are in the form of a double lever.

4. Injection pump governor according to any one of the preceding claims, wherein the guide bush bears a fixed sleeve cooperating part on which the sleeve rotatably mounted on the guide bush is supported via a needle bearing.

7 1 5. Injection pump governor according to any one of the preceding claims, wherein the shaft of the articulated head has shaft components with different sized diameters, of which the larger shaft component is exposed and, together with the front side of the guide bush, defines the path of negative adjustment 6. Injection pump governor according to any preceding claims, wherein the pretensioning supported at one end on the articulated head other end, on a shoulder of the guide bush.

one of the spring is and, at the 1 1. Injection pump governor according to any one of the preceding claims, wherein the intermediate lever is in the form of a rocking lever having a bearing bolt which is rigidly connected to this lever and mounted in the reversing lever.

8. Injection pump governor according to any one of the preceding claims, wherein there is arranged at the free end of the bearing bolt a play compensating spring which is attached to this bolt and supported on the reversing lever and presses the intermediate lever without play against the sleeve cooperating part.

9. Injection pump governor according to claim 1, szlierein the upper free end of the intermediate lever which is remote from the sleeve cooperating part has a bearing bolt on which the control arm is rotatably mounted.

10. Injection pump governor substantially as hereinbefore described with reference to and as illustrated in the accompanying drawings.

Published 1989 at The Patent Office, State House, 6671 High holloorn. London WCIR 4TP. Further copies mkybe obtaaned from The Patent Office. Sales Branch, St Mary Cray, Orpington, Kent BR.5 3RD. Printed by Multiplex techniques ltd, St Mary Cray, Kent, Con. 1/87