Automatic transmission control for an automotive vehicle driveline having fail-safe logic
US4494423A · kind A · utility
31Cited by
12References
8Claims
0Family size
Assignee
Inventors
Key dates
| Filing date | Aug 4, 1982 |
| Grant date | Jan 22, 1985 |
| Priority date | — |
| Expiry date | Aug 4, 2002 |
Classification
- Technology area (CPC F)Mechanical Engineering; Lighting; Heating
- CPC primaryF16H2061/1268
- WIPO fieldMechanical elements
- WIPO sectorMechanical engineering
Abstract
A control system for operating the clutch and brake elements of a multiple speed ratio transmission includes a manual valve that opens line pressure to a transfer valve, which in its first state pressurizes a feed line through which any of the clutches and servos may be selectively pressurized. In its second state, the transfer valve pressurizes the clutches whose engagement that produces a predetermined speed ratio. The detector valve moves the transfer valve to the second state if the combination of pressurized clutches and servos is other than the combination that produces a drive ratio in normal operation.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.