Hydraulic actuator system having non-cavitating flow equalizer
US4949540A · kind A · utility
Assignee
Inventor
Key dates
| Filing date | Nov 21, 1988 |
| Grant date | Aug 21, 1990 |
| Priority date | — |
| Expiry date | Nov 21, 2008 |
Classification
- Technology area (CPC Y)Emerging Cross-Sectional Technologies
- CPC primaryY10T137/2516
- WIPO fieldHandling
- WIPO sectorMechanical engineering
Abstract
A hydraulic system having multiple actuators is provided with positive pressure flow equalization for both advancing and retracting movements of the system by means of first and second flow divider elements for each actuator. The flow divider elements are cross-coupled between the actuators, a controllable source of pressurized fluid and a reservoir. The flow divider elements are positive-displacement gear or vane pump units that are connected by a common shaft for coordinating fluid flow to the various actuators. Two or more of the actuators can be connected for lifting a load such as an automobile, the system being provided with safety latches at each actuator, the flow dividers not only coordinating the actuator movements during normal raising and lowering operation, but also preventing loss of synchronization of the actuators in case of engagement of a subset only of the latches. Synchronism is maintained even under negative loading because positive pressure is maintained between the dividers and each of the actuators, preventing cavitation.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.