Gear shift control apparatus
US5865708A · kind A · utility
Assignee
Inventors
Key dates
| Filing date | Jan 23, 1997 |
| Grant date | Feb 2, 1999 |
| Priority date | — |
| Expiry date | Jan 23, 2017 |
Classification
- Technology area (CPC F)Mechanical Engineering; Lighting; Heating
- CPC primaryF16H2061/0477
- WIPO fieldMechanical elements
- WIPO sectorMechanical engineering
Abstract
A gear shift control apparatus for use in an automatic transmission having friction elements each of which is operable on a working fluid pressure applied thereto in an engaged and released state. A change is produced from the current gear ratio to a desired gear ratio by increasing the pressure of the working fluid to a first one of the friction elements at a first rate to engage the first friction element while decreasing the pressure of the working fluid to a second one of the friction elements at a second rate to release the second friction element. A time elapsed for a torque phase in the gear ratio change is measured. The first rate is decreased when the measured torque phase time is shorter than a predetermined value. The second rate is increased when the measured torque phase time is longer than the predetermined value.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.