| 摘要 |
<p><P>PROBLEM TO BE SOLVED: To provide a compact and inexpensive four-way switch valve. <P>SOLUTION: A three-way switch valve having a valve element 3 for switching a port B to a port D through a port A or a sleeve 2, a three-way switch valve having a valve element 4 for switching a port C to the port A or the port D, and a piston 18 for driving these three-way valves, are coaxially mounted in a cylindrical body 1. A three-way solenoid valve 19 introduces high pressure to a pressure chamber at an upper part of the piston 18 to downwardly driving the valve elements 3, 4 held on the sleeve 2, and the valve elements 3, 4 are upwardly driven by driving force generated by making pressure receiving areas of guides 7, 8 larger than that of a guide 6. Thus, a structure is totally simplified and miniaturized, and further since a body is machined by uniaxial machining, the manufacturing cost is reduced. The valve elements 3, 4 are not simultaneously seated, and the movement in the seating direction of the valve element seated first is absorbed by springs 9, 10 to exclude sealing failure. <P>COPYRIGHT: (C)2003,JPO</p> |
