摘要 |
A dual brake valve assembly for use in fluid pressure-operated vehicle braking systems embodying two independent braking circuits comprises a housing provided with sets of primary and secondary ports associated respectively with the two braking circuits and each consisting of a supply port for connection to a source of fluid under pressure and a delivery port for connection to a brake actuator, an exhaust, and two co-axial primary and secondary valves which are operative, when actuated, to isolate the delivery ports from the exhaust and connect them to the respective supply ports. A primary piston operates the primary valve directly and acts through the primary valve and a secondary piston to operate the secondary valve. The secondary piston is provided with passages through which the respective supply and delivery ports of each set are placed in communication when the respective primary and secondary valves are operated.
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