Transmission and control with centrifugal dump valve
US4082012A · kind A · utility
Assignee
Inventors
Key dates
| Filing date | Jan 17, 1977 |
| Grant date | Apr 4, 1978 |
| Priority date | — |
| Expiry date | Jan 17, 1997 |
Classification
- Technology area (CPC F)Mechanical Engineering; Lighting; Heating
- CPC primaryF16D2500/7041
- WIPO fieldMechanical elements
- WIPO sectorMechanical engineering
Abstract
A multiratio powershift transmission having fluid operated drive devices including a forward clutch with an apply chamber supplied with fluid apply pressure to engage the clutch for forward drives and exhausted to disengage the clutch for reverse drive. The apply chamber is in a housing rotating at input speed during forward and reverse drive. In forward drive, a dump valve mounted on the rotating housing is biased closed by a spring, static fluid apply pressure, and centrifugal pressure head, in the rated input speed range. At a higher speed, centrifugal force on the dump valve element opens the dump valve to exhaust the apply chamber and disengage forward drive. In reverse drive, the dump valve is biased closed only by the spring which at idle speed closes the dump valve, and at a low speed used in reverse drive, centrifugal force opens the dump valve to flush the dump valve during reverse drive.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.