Electric power steering control device for automotive vehicle
US5414627A · kind A · utility
Assignees
Inventors
Key dates
| Filing date | Aug 10, 1993 |
| Grant date | May 9, 1995 |
| Priority date | — |
| Expiry date | Aug 10, 2013 |
Classification
- Technology area (CPC B)Performing Operations; Transporting
- CPC primaryB62D5/0463
- WIPO fieldTransport
- WIPO sectorMechanical engineering
Abstract
An electric power steering control device includes a motor controller for controlling an electric motor providing the assisting steering torque; and a clutch controller for controlling an electromagnetic clutch selectively connecting the assisting steering torque of the motor to the steering system. The degree of engagement (connection) of the clutch corresponds to the clutch current command level I.sub.C. When the vehicle speed is above a predetermined speed V.sub.0 (i.e., during high speed driving), the clutch current I.sub.C is set at a predetermined half current level I.sub.CR. During low vehicle speeds below V.sub.0, the clutch current I.sub.C is gradually decreased to the half current level I.sub.CR as the vehicle speed increases to V.sub.0. When the steering torque T is above a first predetermined level T1 indicative of an abnormality during high speed operation, the clutch current I.sub.C is set at a minimal level I.sub.CO. The steering torque T is returned to the half current level I.sub.CR when it is below a second predetermined level T2 smaller than the first level T1, thereby avoiding steering torque hunting.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.