Patent · US Expired

Variable ratio master cylinder

US3981146A · kind A · utility

1Cited by
6References
15Claims
0Family size

Assignee

Inventors

Key dates

Filing dateSep 13, 1972
Grant dateSep 21, 1976
Priority date
Expiry dateSep 13, 1992

Classification

  • Technology area (CPC B)Performing Operations; Transporting
  • CPC primaryB60T11/22
  • WIPO fieldTransport
  • WIPO sectorMechanical engineering

Abstract

A variable ratio master cylinder designed to operate, in one phase, to take up slack in a braking system by displacing a relatively large volume of fluid at a low pressure with minimum pedal travel and then gradually shift to another phase in which a smaller volume of fluid is displaced at a higher pressure with increased pedal travel to apply the brakes. The master cylinder includes a differential area metering valve which begins to open at a predetermined pressure in the pressure chamber and remains open above a predetermined second pressure and sealing means cooperative with at least one piston to seal off communication between the pressure chamber and the rear of the piston during the pressure stroke of the piston but to allow communication between said chambers on the return stroke of the piston for rapid return to the released state.

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