Abstract: A master cylinder includes a housing (24) with a bore (26) receiving a pair of pistons (42, 48). The piston (48) engages seals (62, 64 and 66) to substantially define paths to a pair of pressure chambers (50, 52).

Abstract: A dual master cylinder (10) includes a pair of pistons (62, 106) moving in a bore (14) to contract a pair of pressure chambers (64, 108). A housing 12 defines a pair of inlets (26, 28) communicating liquid from a reservoir (18) into the pair of pressure chambers (64, 108). A pair of outlets (46, 48) communicate liquid from the pair of pressure chambers (64, 108) to a pair of brake systems (50, 52). A pair of tilt valves (34, 36) control liquid communication through the inlets (26, 28). The pair of pistons (62, 106) carry a pair of valve actuators (182, 210) which open and close the pair of tilt valves (34, 36) in response to movement of the pair of pistons (62, 106) within the housing (12). The pair of actuators (182, 210) cooperate with one another to simultaneously close the pair of tilt valves (34, 36) during a brake application.