Hydraulic control apparatus for belt-drive CVT of vehicle
US7553256B2 · kind B2 · utility
Assignee
Inventors
Key dates
| Filing date | Jul 17, 2006 |
| Grant date | Jun 30, 2009 |
| Priority date | — |
| Expiry date | Sep 26, 2027 |
Classification
- Technology area (CPC F)Mechanical Engineering; Lighting; Heating
- CPC primaryF16H61/66254
- WIPO fieldMechanical elements
- WIPO sectorMechanical engineering
Abstract
A hydraulic control apparatus of a belt-drive CVT, controlling a transmission ratio by changing respective effective rotation radii of driving and driven pulleys, includes vehicle information sensors; hydraulic actuators changing the respective rotation radii; and a control unit determining each fluid pressure command value provided for the pulleys, and controlling the hydraulic actuators based on the fluid pressure command values. The control unit acquires an actual displacement amount of one of the pulleys. When changing a transmission to the highest or lowest speed transmission, the control unit sets a target displacement amount of one of the pulleys; estimates a rapidly changing amount of the working fluid pressure, occurring at close to an end of the speed change; and corrects the fluid pressure command value by the rapidly changing amount at a time when a rate of the actual displacement amount with respect to the target displacement amount has reached a predetermined rate α0.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.