Hydraulic pressure control system for hydraulically operated vehicle transmission
US5702322A · kind A · utility
Assignee
Inventors
Key dates
| Filing date | Feb 29, 1996 |
| Grant date | Dec 30, 1997 |
| Priority date | — |
| Expiry date | Feb 29, 2016 |
Classification
- Technology area (CPC F)Mechanical Engineering; Lighting; Heating
- CPC primaryF16H59/40
- WIPO fieldMechanical elements
- WIPO sectorMechanical engineering
Abstract
A system for controlling a vehicle automatic transmission, in which a gear ratio to be shifted to is determined based on the vehicle speed and throttle opening degree and a clutch is supplied with hydraulic pressure such that the rotational speed of the transmission input shaft concurs with a desired rotational speed change rate. The system includes means for discriminating whether the engine load fluctuates and the operation is discontinued when it is discriminated that the engine load fluctuates. Specifically, even when the accelerator pedal is operated only somewhat rapidly and the engine output is able to follow the change in the degree of throttle opening, the degree of throttle opening nevertheless differs between that at the start of gearshift and that in the course of gearshift thereafter, causing unexpected gearshift shock to occur. The arrangement can solve the problem.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.