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:
Sep. 29, 1987
Filed:
Mar. 13, 1986
Denis J McCann, Crickhowell, GB;
Colin F Ross, Crickhowell, GB;
Lucas Industries Public Limited Company, Birmingham, GB;
Abstract
A trailer air braking system has combined spring brake and service brake actuators, and the service brake chambers of the actuators are controlled by a combined emergency relay and modulator valve assembly of known construction. In order to ensure that the spring brake function does not become operative due to a moderate loss in the pressure of the trailer reservoir, such as would occur in the event of an anti-skid test in which the reservoir is isolated from the emergency line and the modulator valve is cycled, a spring brake one-way control valve is inserted into the spring brake circuit leading from the reservoir. The control valve acts in one condition as a one-way valve to prevent air returning from the spring brake actuator chamber to the reservoir, but on a large loss in reservoir pressure, a piston which carries the one-way valve seat and is subjected to reservoir pressure moves under spring biassing such that the one-way poppet valve member is unseated by a control pin to permit a reduction in spring brake pressure.