Control circuit for a double-acting hydraulic jack and slide distributor for such a circuit
US5214997A · kind A · utility
Assignee
Inventor
Key dates
| Filing date | Apr 2, 1991 |
| Grant date | Jun 1, 1993 |
| Priority date | — |
| Expiry date | Apr 2, 2011 |
Classification
- Technology area (CPC F)Mechanical Engineering; Lighting; Heating
- CPC primaryF15B13/01
- WIPO fieldMechanical elements
- WIPO sectorMechanical engineering
Abstract
The control circuit of a double-acting hydraulic jack (10), consisting of a piston (12) connected to an output rod (18) and separating a cylinder into two chambers (14, 16), comprises a source of fluid under pressure (20, 26), a distribution system (28, 28', 52, 52') alternately putting one of the chambers, or control chamber, in communication with the source of fluid under pressure (20, 26) and the other chamber, or controlled chamber, in communication with a reservoir of fluid under low pressure (25), in order to control the movement of the piston (12) of the jack (10). The jack comprises an auxiliary circuit (50, 120, 122) for preventing communication between the controlled chamber and the reservoir (25), interrupting communication between the control chamber and the source of fluid under pressure (20, 26) and allowing communication between the controlled and control chambers when the pressure of the fluid in the controlled chamber exceeds a predetermined value.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.