Patent · US Expired

Pneumatic brake booster piston with sleeve defining quick-fill input chamber

US4942738A · kind A · utility

3Cited by
9References
14Claims
0Family size

Assignee

Inventor

Key dates

Filing dateJul 30, 1987
Grant dateJul 24, 1990
Priority date
Expiry dateJul 30, 2007

Classification

  • Technology area (CPC B)Performing Operations; Transporting
  • CPC primaryB60T13/565
  • WIPO fieldTransport
  • WIPO sectorMechanical engineering

Abstract

In a booster casing (12) a movable wall (14) separates two compartments (16,18) from each other. In inoperative position, a control valve (20) connects the two compartments (16,18) with each other, and separates them when in an operative position, connecting one (16) of them to a source of pressure which differs from the pressure in the other compartment (18). A cylinder casing (52) is attached to the booster casing (12), projects into the same, and contains at least one pressure piston (54) which defines a pressure chamber (56) for pressurizing a brake circuit. An input piston (40) having a greater effective surface than the pressure piston (54) and defining an input chamber (42) is movable together with the movable wall (14). The input chamber (42) is adapted to be relieved of pressure by a relief valve (80) if the booster (10) fails. The input piston (40) and chamber (42) are arranged inside the booster casing (12), and the input piston (40) forms part of the movable wall (14). This permits a simple design of the assembly which is particularly space-saving, with a given specification of its performance.

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