Hydraulic variable-displacement axial piston pump having torque limitation
US4255092A · kind A · utility
Assignee
Inventors
Key dates
| Filing date | Oct 3, 1978 |
| Grant date | Mar 10, 1981 |
| Priority date | — |
| Expiry date | Oct 3, 1998 |
Classification
- Technology area (CPC F)Mechanical Engineering; Lighting; Heating
- CPC primaryF04B49/10
- WIPO fieldEngines, pumps, turbines
- WIPO sectorMechanical engineering
Abstract
A hydraulic variable-displacement axial piston pump comprising a swash means which tends to move to a de-swashed condition when the pump is working, and a torque limiting device, the torque limiting device comprising a piston and cylinder arrangement having a movable member which when extended acts via the swash means to increase the displacement of the pump, a spool, and a spring which has one end acting on the spool and its other end acting on the movable member thereby placing the spool under a spring load which varies with the extension of the movable member, the spool being coupled to pump delivery pressure at its end remote from the spring and the spool being arranged to control the flow of fluid to the movable member, whereby a limitation on the on-swash condition of the swash means is obtained which is inversely proportional to the pressure at which the hydraulic fluid is discharged from the pump.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.