Patent · US Expired

Two-stage concentric hydraulic brake booster

US4287813A · kind A · utility

7Cited by
1References
12Claims
0Family size

Assignee

Inventors

Key dates

Filing dateDec 20, 1979
Grant dateSep 8, 1981
Priority date
Expiry dateDec 20, 1999

Classification

  • Technology area (CPC Y)Emerging Cross-Sectional Technologies
  • CPC primaryY10T137/86582
  • WIPO fieldTransport
  • WIPO sectorMechanical engineering

Abstract

Booster providing both hydraulic feed-back and hydraulic feel-back in a two-stage operation in which we boost-brake a vehicle. Concentric, nesting, inner and outer control parts include, as the sliding outer part, a brake-pedal-connected input signal spool or sleeve for developing a desired signal pressure varying linearly along the length of, and therefore according to the sliding position of, the sleeve; the inner part constitutes a captive, telescoping metering spool with its ends in corresponding ends of the spool sleeve. At one end, the metering spool is given the desired signal as a first stage pressure to respond to; the spool's response constitutes the second stage, by metering an actual pressure and applying it at the other end of the spool sleeve and spool, whereby hydraulic feed-back comes on in the second stage at actual pressure to responsively control the other end of the metering spool, and whereby hydraulic feel-back in the second stage comes on at the same actual pressure to exert itself on the other end of the spool sleeve and therefore react against the brake pedal.

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