The patent badge is an abbreviated version of the USPTO patent document. The patent badge does contain a link to the full patent document.
The patent badge is an abbreviated version of the USPTO patent document. The patent badge covers the following: Patent number, Date patent was issued, Date patent was filed, Title of the patent, Applicant, Inventor, Assignee, Attorney firm, Primary examiner, Assistant examiner, CPCs, and Abstract. The patent badge does contain a link to the full patent document (in Adobe Acrobat format, aka pdf). To download or print any patent click here.
Patent No.:
Date of Patent:
Mar. 28, 1995
Filed:
Dec. 13, 1993
Donald D Johannesen, South Bend, IN (US);
AlliedSignal Inc., Morristown, NJ (US);
Abstract
The drum brake wheel cylinder (20) comprises a longitudinal through bore (16) having therein a pair of opposed pistons (22, 24) with each piston (22, 24) engaging a respective web (12, 14) of an adjacent drum brake shoe. A first piston (22) includes a longitudinal opening (32) receiving therein one end (62) of a friction rod (60), and the second piston (24) includes a recess opening (27) receiving therein the second end (64) of the friction rod. A friction latch adjusting lever (50) has a central opening (52) receiving therethrough the friction rod (60) and is located diagonally relative to a longitudinal axis of the friction rod (60). A spring (70) is located about the friction rod (60) with one end biasing the friction latch adjuster lever (50) against a wall (34) of the first piston (22) and the other end of the spring engaging an abutment (27B) in the recess opening (27 ). The first piston (22) includes a through opening (36) receiving slidably therein an adjuster release pin (40) which extends into a slot opening (56) of the friction latch adjusting lever (50). A running clearance (X) is defined between a head (66) at the second end (64) of the friction rod (60) and the abutment (27B) at the opening recess (27). Hydraulic pressure which displaces the pistons (22, 24) a distance greater than the running clearance (X) causes the friction rod (60) to be displaced relative to the friction latch adjusting lever (50) which effects an adjusted at-rest position of the pistons (22, 24) in accordance with drum brake shoe lining wear.