Patent · US Expired

Bootstrap power steering systems

US5682745A · kind A · utility

26Cited by
3References
6Claims
0Family size

Assignee

Inventor

Key dates

Filing dateOct 10, 1995
Grant dateNov 4, 1997
Priority date
Expiry dateOct 10, 2015

Classification

  • Technology area (CPC H)Electricity
  • CPC primaryH02K7/14
  • WIPO fieldTransport
  • WIPO sectorMechanical engineering

Abstract

Methods and devices for enabling simplified bootstrap hydraulic systems for use in bootstrap hydromechanical and electrohydraulic vehicular power steering systems are disclosed. A simplified bootstrap control valve is provided wherein the control valve's load circuit is not interdicted in any way. The simplified bootstrap control valve comprises a four-way control valve having input slots formed in an open-center manner, intermediate slots formed in an open-center manner, return slots formed in a closed-center manner, and a passage for picking off the pressure value present in the intermediate slots. The pressure value present in the intermediate slots is utilized for regulating pumping apparatus providing fluid to the simplified bootstrap control valve such that pressure value present in the intermediate slots is substantially maintained at a preselected value. A simplified servo motor-positive displacement pump assembly of integrated construction is also provided. The simplified servo motor-positive displacement pump assembly includes a common central housing and a quill drive.

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