发明授权
- 专利标题: Valve apparatus and hydraulic drive system
- 专利标题(中): 阀门装置和液压驱动系统
-
申请号: US655368申请日: 1991-02-28
-
公开(公告)号: US5203678A公开(公告)日: 1993-04-20
- 发明人: Genroku Sugiyama , Toichi Hirata , Yusuke Kajita
- 申请人: Genroku Sugiyama , Toichi Hirata , Yusuke Kajita
- 申请人地址: JPX Tokyo
- 专利权人: Hitachi Construction Machinery Co., Ltd.
- 当前专利权人: Hitachi Construction Machinery Co., Ltd.
- 当前专利权人地址: JPX Tokyo
- 优先权: JPX2-2539 19900111
- 主分类号: E02F9/22
- IPC分类号: E02F9/22 ; F15B13/04
摘要:
A valve apparatus has a flow control valve having a supply passage communicating with a hydraulic fluid supply source, a load passage communicating with an actuator, and a first meter-in variable restrictor disposed between the supply passage and the load passage and opened dependent on an operation amount there; a first signal passage located downstream of the first variable restrictor and having a passage section for detecting load pressure of the actuator; a tank passage communicating with a reservoir tank; a discharge passage for communicating the first signal passage with the tank passage; and a second variable restrictor provided in the discharge passage and having its opening variable dependent on the operation amount of the flow control valve to produce in the first signal passage a control pressure different from the load pressure, the control pressure in the first signal passage being led to the hydraulic fluid supply source though a second signal passage. An auxiliary restrictor is disposed in the first signal passage to reduce the load pressure detected in the passage section of the first signal passage so that a pressure lower than the detected load pressure is produced in the first signal passage as the control pressure.
公开/授权文献
- US4079240A Asynchronous to synchronous converter 公开/授权日:1978-03-14
信息查询