Patent ID: 6089529
Filing Date: 2000-07-18
Classification: F02M

Abstract:
A valve for controlling liquids, comprising a valve member (22) which is actuatable via a hydraulic step-up means (25) and which is urged in a closing direction onto a valve seat (20) by a compression spring (23), the hydraulic step-up means (25) has a pressure chamber (26) that is defined on one side by a piston (28) of a piezoelectric actuator (24), by whose motion a change in pressure in the pressure chamber (26) occurs, which on an other side acts on a piston (29) of the valve member (22), said pistons (28 and 29) also defines the pressure chamber (26) by which the valve member (22) is adjustable in an opening direction counter to a force of the compression spring (23), said pistons (28,29) being guided in respective guide bores, a control chamber (32 or 33) is formed on a back side of at least one of said pistons said control chamber being tightly closed off by a diaphragm (34 or 35) at a remote side of said back side of said piston and being connected with said pressure chamber (26) by a leakage path between said piston and the guide bore of said piston and with, a low-pressure source (40) via a throttle bore (36 or 37).