Hydraulic pressure control for reducing engagement shock of automatic transmission
US4953090A · kind A · utility
Assignee
Inventor
Key dates
| Filing date | Aug 27, 1987 |
| Grant date | Aug 28, 1990 |
| Priority date | — |
| Expiry date | Aug 27, 2007 |
Classification
- Technology area (CPC F)Mechanical Engineering; Lighting; Heating
- CPC primaryF16H2061/0096
- WIPO fieldMechanical elements
- WIPO sectorMechanical engineering
Abstract
A hydraulic pressure control system for reducing engagement shock of a frictional element in an automatic transmission, comprises an electromagnetically operated valve for generating a hydraulic pressure supplied to the frictional element, and a control unit for controlling the hydraulic pressure such that the level of the hydraulic pressure generated is adjusted to a target value. In the control unit, the difference in the torque applied to the transmission output shaft owing to a shifting operation is determined, the length of time from the beginning of an inertia phase to the end of the inertia phase is determined, the mean rate of change in the torque of the output shaft during the length of time is determined, and the target value is determined such that the torque on the transmission output shaft varies at the mean rate of change during the inertia phase.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.