Patent · US Expired

Hydraulic brake actuator with parking brake

US4733602A · kind A · utility

14Cited by
8References
15Claims
0Family size

Assignee

Inventors

Key dates

Filing dateMar 17, 1986
Grant dateMar 29, 1988
Priority date
Expiry dateMar 17, 2006

Classification

  • Technology area (CPC B)Performing Operations; Transporting
  • CPC primaryB61H15/00
  • WIPO fieldTransport
  • WIPO sectorMechanical engineering

Abstract

A hydraulic brake actuator including a hydraulic parking brake that can be applied by mechanically locking up either a normal service brake application or a hand pump operated brake application. The lock-up mechanism includes a friction collar that surrounds the piston push rod and a hand pump actuated locking member that surrounds the friction collar. The friction collar and locking member have complementary conical surfaces that are engageable when hydraulic hand pump pressure is applied to a piston face of the locking member to wedge the friction member into pressure engagement with the piston push rod, as a means of locking up the push rod to obtain a parking brake. The locking member also includes a plurality of spring-like fingers that project axially from the periphery of the locking member and are provided with latching tabs adapted to enter a recess in the body to prevent return-movement of the locking member when the hydraulic hand pump operation is terminated. A plug member is provided to prevent the tabs from being disengaged from the recess. This provides a means for releasing the locking mechanism by either manually or hydraulically withdrawing the plug member, thereb…

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