Hydraulic actuator in automatic transmission
US5232418A · kind A · utility
Assignee
Inventors
Key dates
| Filing date | Dec 17, 1991 |
| Grant date | Aug 3, 1993 |
| Priority date | — |
| Expiry date | Dec 17, 2011 |
Classification
- Technology area (CPC F)Mechanical Engineering; Lighting; Heating
- CPC primaryF16H2200/2056
- WIPO fieldMechanical elements
- WIPO sectorMechanical engineering
Abstract
A double-acting hydraulic actuator structure for use in an automatic transmission has a two-layered structure which includes first and second frictional engagement element hydraulic actuators. The first hydraulic actuator includes a drum member and a first piston fitted hermetically and slidably in the drum member. The second hydraulic actuator is formed by the interior of the first piston and a second piston fitted hermetically and slidably mounted within the first piston. The first and second pistons are both urged toward their disengaged positions by the action of a common return spring. A second spring is provided for urging the second piston alone against the force of the return spring.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.