Patent ID: 7234486

Claim:
Pressure limiting valve for fuel injection devices, particularly for fuel injection devices of internal-combustion engines constructed as common-rail systems, comprising a housing with an inlet-side high-pressure connection, a return flow connection and a throttling flow connection situated between them, which has a valve seat on the inlet side and in which, in a spring-loaded manner in the direction of the closing position and displaceably as a function of the pressure in the opening direction, a valve body interacting with the valve seat as well as a piston arranged behind the valve seat in the direction of the return flow bound a pressure space, the piston, while sealingly moving in a sliding guide being arranged in a stable manner with respect to the coaxial valve body, and, relative to the piston and the valve body as a unit, when the pressure space is opened with respect to the high-pressure connection, the effective surfaces of the unit pressurized against the spring force being larger than when the pressure space is blocked off with respect to the high-pressure connection, wherein the sliding guide has a connection cross-section which is overlapped by the piston; wherein the piston, in a closing position of the valve body, covers the connection cross-section in the closing direction in an overlapping manner; wherein a damping space connected with the pressure space is assigned on the spring side to the unit of the valve body and the piston; and wherein a compensating pin, which penetrates the damping space and influences the difference between the pressurized effective surfaces, is assigned on the spring side to the unit of the valve body and the piston, and wherein the compensating pin opposite the piston is slidingly in a sealing manner guided in a guide bore which receives the spring.