Hydraulic control apparatus for V-belt type continuously variable transmission
US7211013B2 · kind B2 · utility
Assignee
Inventors
Key dates
| Filing date | Sep 12, 2003 |
| Grant date | May 1, 2007 |
| Priority date | — |
| Expiry date | Feb 16, 2025 |
Classification
- Technology area (CPC F)Mechanical Engineering; Lighting; Heating
- CPC primaryF16H2059/6823
- WIPO fieldMechanical elements
- WIPO sectorMechanical engineering
Abstract
There is provided a hydraulic control apparatus for a belt CVT, which is comprised of a pulley pressure control section that controls the line pressure in accordance with the oil amount balance of an oil pump based on the engine speed and the oil temperature during a select-judgment period from the detection of a change from a driving range to a non-driving range or a change from the non-driving range to the driving range to the lapse of a predetermined period of time, or when the non-driving range is detected. This eliminates the possibility that the oil pump cannot generate a specified oil pressure due to a decrease in the engine speed. Further, the secondary pressure is multiplied by the ratio of the line pressure in accordance with the oil amount balance of the oil pump to the line pressure which has been intended to be specified, and the secondary pressure is controlled according to the calculation result. This makes it possible to maintain the pulley ratio without causing a down-shift of the belt CVT.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.