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. 05, 1990
Filed:
Aug. 20, 1989
John M Graham, San Mateo, CA (US);
Abstract
An air brake includes a service brake chamber which actuates a push rod. A collet brake chamber is partially defined by a collet brake diaphragm. A locking collet is mounted to the collet brake diaphragm and includes a bore through which the push rod passes. A collet brake spring biases the collet into a tapered collet hole to clamp the collet onto the push rod to prevent the movement of the push rod toward the brake off position. Application of pressure to the collet brake chamber overcomes the force of the collet brake spring and moves the collet away from the tapered collet hole to allow the push rod to move freely. Excessive force on brake drums, caused by cooling and contracting brake drums while parked, can be reduced by permitting the collet and push rod therewith to deflect when such excessive force occurs.