Method of controlling electric vehicle transmission
US9975557B2 · kind B2 · utility
Assignees
Inventors
Key dates
| Filing date | May 2, 2016 |
| Grant date | May 22, 2018 |
| Priority date | — |
| Expiry date | Jan 25, 2037 |
Classification
- Technology area (CPC F)Mechanical Engineering; Lighting; Heating
- CPC primaryF16H2306/50
- WIPO fieldMechanical elements
- WIPO sectorMechanical engineering
Abstract
A method of controlling an electric vehicle transmission includes: a torque-securing step of securing a predetermined spare torque to be generated by a motor in accordance with a current motor torque when a controller determines that there is a need for downshift from an upper gear step to a lower gear step; a slip-controlling step of generating a friction force through a servo clutch applying a friction force between an input shaft and a servo driving gear of a pair of servo gears; a shifting-to-neutral step of shifting to a neutral gear by disengaging a synchronizer for the upper gear step; a motor-synchronizing step of synchronizing a rotational speed of the motor with a desired speed of a lower gear step using the spare torque of the motor secured in the torque-securing step; a gear-engaging step of engaging a synchronizer for the lower gear step; and a clutch-disengaging step of finishing shifting by disengaging the servo clutch.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.