摘要 |
A proportional valve is provided comprising a valve (1) comprising a housing (2) having an inlet (3) and an outlet (4), a valve element (5) being positioned between said inlet (3) and said outlet (4), said valve element (5) being moveable in said housing (2), said valve element (5) having a pilot valve opening (7), a first pressure chamber (16), a pressure in said first pressure chamber (16) acting on said valve element (5) in a first direction, a second pressure chamber (17), a pressure in said pressure chamber (17) acting on said valve element (5) in a second direction opposite to said first direction, a pilot valve element (6) cooperating with said pilot valve opening (7) to form a pilot valve, said pilot valve element (6) being actuated by drive means (8), wherein a flow resistance between said inlet (3) and said first pressure chamber (16) is smaller than a flow resistance between said inlet (3) and said second pressure chamber (17). In such valve it is possible to reduce the electrical power needed to operate the solenoid. To this end said pilot valve opens into a third pressure chamber (19), said third pressure chamber (19) being connected to said outlet (3) via a throttled flow path (20). |