Braking system in vehicle - has multi-circuit safety valve using piston with three parallel working surfaces

摘要

Multi-circuit safety valave has transfer valves for each circuit to give priority ranked and individually supplied circuits controlled by block/release valves. The control valve (13) piston (54) should have three parallel working surfaces (55, 56, 57) of which two (55, 56) are loaded by the output pressure of the two transfer valves (1, 2) allocated to the priority circuits (I, II). The third surface (57) is loaded by the input/output pressure from the valve (3 or 4) of the low priority circuit (III or IV). Pref. all surfaces are equal in area. USE/ADVANTAGE - Motor vehicles, braking systems. Valve system awards and retains circuit priorities but automatically energises low priority circuit is one priority circuit fails.