Regulating arrangement of a fuel-injection pump with a lever

The lever (13) cooperates on the one hand with a rotatable part (12) and, on the other, is coupled with a to-and-fro movable adjusting member (14). The lever (13) consists of a housing (15) traversed by the rotatable part (12), of a piston-like spring plate (16) and of a return spring (19) clamped-in between housing (15) and sping plate (16). Spring plate (16) and rotatable part (12) form in the mutually cooperating area a torque-limiting driving device. The hollow space (25) underneath the spring plate (16) is adapted to be acted upon with oil pressure by bores (21, 22) in the rotatable part (12) which are controllably connected to a pressure oil source (24). The oil pressure displaces the spring plate (16) so that the driving device is disengaged. The lever (13) is then displaced by the spring (27) of the to-and-fro movable part into an end position independently of the position of the rotatable part (12) which corresponds to the zero delivery of the fuel injection pump (11).

The invention relates to a regulating arrangement of a fuel-injection pump 
with a lever. The blocking of the regulating device by a jamming pump 
piston in one of the coupled fuel-injection pumps is prevented by the 
torque-limiting driving device between rotatable part and lever. The other 
fuel-injection pumps ready for operation can therefore be continued to be 
regulated so that the internal combustion engine in question remains 
limitedly operational. 
Regulating arrangements of this type are known from the DE-PS No. 564 169 
and the DE-OS No. 34 06 646. Furthermore, it is known from the DE-PS No. 
29 50 633 to move the to-and-fro movable adjusting member of a 
fuel-injection pump into an end position by an axial force independently 
of the position of the lever which end position corresponds to the zero 
delivery of the pump piston. The stopping of the to-and-fro movable 
adjusting member changes the position of the lever independently of the 
instantaneous position of the rotatable part. As a result thereof, the 
driving device is displaced from its off-position against the force of the 
return spring. The restoring moment then resulting at the lever acts by 
way of the rotatable part on the regulator of the internal combustion 
engine coupled with the regulating arrangement and reduces the operating 
capability of the regulator in an undesired manner. 
The sum of the torques which, during the stopping of adjusting members can 
act back on the regulator, must not exceed the operating capability of the 
regulator as otherwise the internal combustion engine is no longer 
operational. A maximum permissive prestress force for the return spring in 
the lever results therefrom for given conditions of a regulating 
arrangement. With known arrangements, the permissive prestress force of 
the return spring is so small that during operation of the internal 
combustion engine, it may lead to strong vibrations at the levers and in 
the entire regulating arrangement which leads to friction wear especially 
at the driving devices. 
It is the task of the invention to create a regulating arrangement, by 
means of which the to-and-fro movable adjusting member of a fuel injection 
pump can be brought remotely actuated into a zero delivery position 
without resulting in a reduction of the operating capability of the 
regulator. 
This task is solved according to the invention with the characterizing 
features of the claims. By opening the controllable valve pressure oil 
reaches by way of the bearing gap between housing and rotatable part the 
driving device side of the spring plate which is lifted thereby and 
renders the driving device inoperable. The lever is therewith freely 
pivotal within limits without load by the return spring. The to-and-fro 
movable adjusting member spring-loaded in the direction of the end 
position for zero delivery of the pump piston is therewith in the position 
to assume under entrainment of the coupled lever the zero delivery end 
position unimpaired by the position of the rotatable part. 
The advantages achieved with the invention consist in particular in that 
the arrangement can be assembled in a simple manner, in that the 
arrangement has a small space requirement, in that the decoupling between 
lever and rotatable part operates without feedback on the connected 
regulator, in that the return spring of the lever can be dimensioned 
without limitation by the regulator operating capacity and in that 
vibrations of the regulating arrangement and of the friction wear 
resulting therefrom are avoided with a greater spring prestress of the 
return spring.

A regulating arrangement for the adjustment of the feed quantity of a fuel 
injection pump 11 consists of a regulator not illustrated, of a rotatable 
part 12 connected with the regulator, of a lever 13 cooperating with the 
rotatable part 12 and of a to-and-fro movable adjusting member 14 coupled 
with the lever 13. 
The piston 17 of the fuel injection pump 11 is adjusted in a known manner 
to different feed quantities by the adjusting member 14. 
The lever 13 consists of a housing 15 which includes a slide-bearing-like 
cross bore 29 for the accommodation of the rotatable part 12, of a 
piston-like spring plate 16 which is arranged in a cylinder bore 18 of the 
housing 15 and of a return spring 19 clamped-in between housing 15 and 
spring plate 16. 
The spring plate 16 includes on the side facing the rotatable part 12 a 
prismatic extension 20 which abuts with its end face at a secant-like flat 
of the rotatable part 12 under prestress by the return spring 19. Spring 
plate 16 and rotatable part 12 form within the mutually cooperating area a 
torque-limiting driving device. 
The rotatable part 12 includes an axially parallel bore 21 which is 
connected by way of a controllable valve 23 with a pressure oil source 24, 
for example, with the lubricating oil system of an internal combustion 
engine. 
Within the area of the driving device, a bore 22 branches off radially from 
the bore 21, which terminates inside of the housing 15 in the bearing gap, 
which is illustrated enlarged in FIG. 1, between cross bore 29 and 
rotatable part 12. 
As soon as the bore 21 is acted upon with pressurized oil, the pressurized 
oil reaches by way of the bearing gap the hollow space 25 between spring 
plate 16 and rotatable part 12. Owing to the pressure building up in the 
hollow space, the spring plate 16 is lifted up to the abutment 26. The 
connection between the prismatic extension 20 of the spring plate 16 and 
of the secant-like flat of the rotatable part 12 is cancelled thereby and 
the torque transmission of the driving device is thereby interrupted. The 
spring 27 of the to-and-fro movable adjusting member 14 now presses the 
lever 13, independently of the position of the rotatable part 12, into the 
zero delivery end position indicated by 28. 
Further fuel injection pumps not illustrated here, which are regulated by 
way of the rotatable part 12 and which include a bore 22 in their lever 
13, are shiftable to zero delivery end position remotely controlled by the 
pressure oil piston actuation. The fuel supply is therewith interrupted in 
the cylinders coordinated to these fuel injection pumps of an internal 
combustion engine. 
The hydraulic disengagement of the driving device prevents the occurrence 
of a restoring moment on the rotatable part 12 so that no reduction of the 
regulator operating capability occurs as a result of disengaged fuel 
injection pumps.