Hydraulically powered actuator for maintaining a member under preload
US4891942A · kind A · utility
Assignee
Inventor
Key dates
| Filing date | Jun 27, 1988 |
| Grant date | Jan 9, 1990 |
| Priority date | — |
| Expiry date | Jun 27, 2008 |
Classification
- Technology area (CPC F)Mechanical Engineering; Lighting; Heating
- CPC primaryF24F8/175
- WIPO fieldThermal processes and apparatus
- WIPO sectorMechanical engineering
Abstract
A hydraulically powered actuator (16) for moving a member (28 or 30) into and away from a position at which the member is under a preload is disclosed. A hydraulically powered motor (22) is utilized which is coupled to the member for moving the member to and from the position at which the member is preloaded. A source (40) of pressurized hydraulic fluid is coupled to the hydraulic motor for supplying power to the motor for moving the movable member. A brake (32) is provided which is coupled to the movable member for holding the movable member in the position at which the member is preloaded. A hydraulic fluid control is provided which is coupled to the motor, the brake and the source of pressurized fluid which activates the brake after the motor has moved the member to the position at which the member is preloaded and deactivates the motor while maintaining the member under preload. The invention eliminates the build-up of heat in hydraulic fluid consequent from the prior art method of establishing preload by applying full hydraulic power to the hydraulic motor to hold the member under preload and further is not subject to leakage which is consequent from maintaining a hydraulic mo…
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.