Patent · US Expired

Vehicular power steering system

US4956590A · kind A · utility

57Cited by
12References
1Claims
0Family size

Assignee

Inventor

Key dates

Filing dateOct 6, 1988
Grant dateSep 11, 1990
Priority date
Expiry dateOct 6, 2008

Classification

  • Technology area (CPC B)Performing Operations; Transporting
  • CPC primaryB62D5/0484
  • WIPO fieldTransport
  • WIPO sectorMechanical engineering

Abstract

A steering assembly for multiplying steering torque and motion applied from a steering wheel of a vehicle by fixed and selectively varying ratios, respectively. The applied steering torque and motion are coupled via an input shaft to a sun gear of a planetary gear set. Supplementary torque and steering motion are generated by a servo motor which is coupled to a ring gear of the planetary gear set via an irreversible differential planetary gear set. Rotational motion of the input shaft is determined and rotational motion of the servo motor is controlled as a selected function of the rotational motion of the input shaft. Actual rotational motion of the servo motor is measured and additional rotational motion of the servo motor is terminated if the actual rotational motion of the servo motor does not substantially match the selected rotational motion. A set of planetary gears mounted in a planetary carrier receives combined output torque and rotational motion from both the sun and ring gears. The planetary carrier is coupled to an output shaft which delivers the output torque and rotational position to a steering gear.

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