Pressure generating device with pressure relief means

Abstract

A pressure generator having a high-pressure accumulator connected to a high-pressure pump by a high-pressure conduit via a first check valve, to store a high-pressure fluid from the high-pressure pump, a charging accumulator connected to the high-pressure pump, for storing a low-pressure fluid and supplying the high-pressure pump with the low-pressure fluid, and a charging pump for supplying the charging accumulator with the low-pressure fluid. The charging accumulator includes leak means for permitting the low-pressure fluid to leak at a low rate. The high-pressure conduit is connected to a storage chamber of the charging accumulator by a communication passage in which is disposed a second check valve for preventing a flow of the fluid from the high-pressure conduit toward the charging accumulator. A valve actuator is provided on one of a piston of the charging accumulator and a valve member of the second check valve, in order to open the second check valve after the fluid in the charging accumulator has leaked out. A valve control device may be provided as to hold the second check valve open for a suitable time immediately after the high-pressure pump is started.