Patent · US Expired

Motor-driven power steering system

US4580648A · kind A · utility

13Cited by
2References
4Claims
0Family size

Assignee

Inventors

Key dates

Filing dateJan 16, 1984
Grant dateApr 8, 1986
Priority date
Expiry dateJan 16, 2004

Classification

  • Technology area (CPC B)Performing Operations; Transporting
  • CPC primaryB62D6/008
  • WIPO fieldTransport
  • WIPO sectorMechanical engineering

Abstract

A power steering system makes use of an electric motor to produce an auxiliary torque added to the torque which is applied to the steering wheel of a vehicle by the driver. The system includes a motor driver for driving the motor and a motor braking circuit for braking the motor. When the torque manually applied to the steering shaft of the vehicle is greater than a predetermined reference torque, an electronic control apparatus causes the motor driver to energize the motor according to the difference between these two torques. When the former torque is less than the reference torque, the control apparatus causes the motor braking circuit to brake the motor. In this way, the torque that the driver of the vehicle must apply to steer the vehicle is maintained equal to the reference torque, irrespective of the vehicle velocity. The reference torque is set by means of a variable-resistor.

Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.