Electric power steering system
US9227653B2 · kind B2 · utility
Assignee
Inventors
Key dates
| Filing date | Apr 10, 2014 |
| Grant date | Jan 5, 2016 |
| Priority date | — |
| Expiry date | Apr 10, 2034 |
Classification
- Technology area (CPC B)Performing Operations; Transporting
- CPC primaryB62D5/0466
- WIPO fieldTransport
- WIPO sectorMechanical engineering
Abstract
An EPS includes a first rack and pinion mechanism that converts rotation of a pinion shaft due to a steering operation, to reciprocating motion of a rack shaft; and a steering force assist device that applies a motor torque of a motor as an assist force by using a second rack and pinion mechanism; and an ECU that controls an operation of the steering force assist device. Rack teeth of the rack shaft constituting the first rack and pinion mechanism are formed so that a steering gear ratio is changed depending on a steering angle. The ECU computes a motor neutral point by subtracting a conversion value from a motor angle detection value. The conversion value is computed based on a steering angle detection value by referring to a conversion map that is set taking into account the steering gear ratio corresponding to the steering angle.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.