发明授权
- 专利标题: Hydraulic elevator and a control method thereof
- 专利标题(中): 液压升降机及其控制方法
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申请号: US843163申请日: 1992-02-28
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公开(公告)号: US5285027A公开(公告)日: 1994-02-08
- 发明人: Ichiro Nakamura , Haruo Watanabe , Tsuyoshi Ogasawara , Katsuharu Shuto , Eiichi Sasaki
- 申请人: Ichiro Nakamura , Haruo Watanabe , Tsuyoshi Ogasawara , Katsuharu Shuto , Eiichi Sasaki
- 申请人地址: JPX Tokyo
- 专利权人: Hitachi, Ltd.
- 当前专利权人: Hitachi, Ltd.
- 当前专利权人地址: JPX Tokyo
- 优先权: JPX3-34042 19910228
- 主分类号: B66B1/00
- IPC分类号: B66B1/00 ; B66B1/04 ; B66B1/26 ; B66B9/04 ; F15B11/00
摘要:
A hydraulic elevator comprises a car, a hydraulic jack to drive the car, a hydraulic pump, and control means for controlling a flow rate of fluid flowing to or from the hydraulic jack thereby to control movement of the car. The control means comprises a main valve constructed so as to allow fluid the flow from the pump into the hydraulic jack when a pressure of the fluid is higher than a predetermined value thereby to effect upward running of the car, and to check a fluid flow from the hydraulic jack when the pressure of the fluid from the pump is less than the predetermined value, and valve control means including a plurality of pilot valves for controlling, when the pressure of the fluid from the pump is less than the value, the main valve to open and close, and wherein the valve control means controls the closing operation of the main valve along at least two different patterns.