Controller for infinite speed ratio transmission
US6317672A · kind A · utility
Assignee
Inventors
Key dates
| Filing date | Jul 12, 2000 |
| Grant date | Nov 13, 2001 |
| Priority date | — |
| Expiry date | Jul 12, 2020 |
Classification
- Technology area (CPC F)Mechanical Engineering; Lighting; Heating
- CPC primaryF16H2037/088
- WIPO fieldMechanical elements
- WIPO sectorMechanical engineering
Abstract
In an infinite speed ratio transmission comprising a continuously variable transmission (2), reduction gear unit (3) and planetary gear set (5), the speed ratio of the continuously variable transmission (2) is controlled by a step motor (36). A range selected by a selector lever (86) is detected by a sensor (84). When the selected range has changed from a stationary range to one of a forward motion range and a reverse motion range, a microprocessor (80) first drives the step motor (36) to a predetermined position (S48, S54). Subsequently, by driving the step motor (36) to an operating position corresponding to a geared neutral point at which the output rotation speed of the infinite speed ratio transmission is zero (S51, S52, S53, S57, S58, S59), the undesirable effects of hysteresis occurring in a relation between the operating position of the step motor (36) and the speed ratio of the continuously variable transmission (2) according to a torque shift of the continuously variable transmission (2) are avoided.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.