| 摘要 |
1. A spool valve (18) comprising a housing (58) which has at least first and second ports (64, 66), a spool (62) which can be moved relative to the housing (58) into at least one position forming a communication or a block between the two ports (64, 66), at least one sealing element (48) which concentrically surrounds the spool (62) and an annular gap between the spool (62) and the housing (58) between the ports (64, 66), characterised in that the sealing element (48) can be moved radially from a position of opening the annular gap into a position of occupying the annular gap after the spool (62) has taken up its position of forming the block in the communication. |
