Creep torque and lock-up control for automatic transmission
US4735113A · kind A · utility
Assignee
Inventors
Key dates
| Filing date | Oct 23, 1986 |
| Grant date | Apr 5, 1988 |
| Priority date | — |
| Expiry date | Oct 23, 2006 |
Classification
- Technology area (CPC F)Mechanical Engineering; Lighting; Heating
- CPC primaryF16H2061/6608
- WIPO fieldMechanical elements
- WIPO sectorMechanical engineering
Abstract
A control device for an automatic transmission comprises an electromagnetic valve that is subject to pulse duty factor control and generates an adjustment pressure variable in a first pattern after a rod of a shift operation mechanism has moved into an overstroke range beyond a maximum reduction ratio position. The adjustment pressure is variable in a second pattern when the rod fails to move into the overstroke range. An adjustment pressure change-over valve is formed integral with the rod and applies the adjustment pressure to a servo actuating pressure regulator valve (i.e., a throttle valve) when the motor vehicle is at a standstill and the engine idles so as to effect a creep torque control. When the motor vehicle starts moving at a speed above a certain vehicle speed, the adjustment pressure change-over valve applies the adjustment pressure to a lock-up control valve, thereby to effect a lock-up control.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.