Abstract: A valve apparatus for prevention of a shocking torque in a clutch mechanism includes a housing having a chamber, the housing including an inlet port for being connected with the master cylinder and an outlet port for being connected with the release cylinder. A valve member is slidably disposed in the chamber to partition the chamber into a first chamber and a second member. The valve member includes a restricted passage connected to the first chamber and the second chamber when the valve member is closed. A first elastic member biases the valve member toward a closed position and a second elastic member biases the valve member in the counter direction of the biassing direction of the first elastic member. A wall member is disposed between the outlet port and the valve member for directing fluid flowing from the outlet port to the valve member.

Abstract: A portless-type master cylinder for use in an automotive fluid brake system has a supporting means which resiliently supports the end of a piston adjacent to a push rod so as to preserve a predetermined gap between the end of a valve rod and a stopper member when the master cylinder is not operating. With this arrangement, the wasteful stroke is minimized and the impact at the time of start-up of the master cylinder is reduced.

Abstract: An inlet assembly for a brake master cylinder includes an inlet member made of synthetic resin installed in the cylinder body of the master cylinder which has at least two inlet portions and one outlet portion positioned between the inlet portions at the same side. The master cylinder is connected through the inlet portion to a hose communicating with a reservoir installed in a vehicle body. The inlet member includes a first member integrally formed of a first tubular portion on a cylinder body side of the inlet member which is fitted into an inlet portion of cylinder body, a second tubular portion for operative engagement with the hose, and a second member having a mounting portion for mounting on the cylinder body by apparatus for positioning the inlet member on the cylinder body and an opening portion which is fitted by a boss portion surrounding the outlet portion of cylinder body.

Abstract: A relief valve used for hydraulic devices such as the master cylinder for motor vehicles, comprising a housing for passing hydraulic fluid therethrough to adjust the hydraulic pressure, a ball valve disposed in the housing, a coil spring for pushing the ball valve in the housing and plural finger-like portions formed in the inside of the housing to resiliently nip the ball valve so as to prevent the vibration of ball valve in the direction of diameter of the housing at the time of releasing hydraulic fluid through the inside of the housing, thereby making it possible to avoid the generation of strange noise by the vibration of ball valve. It is desirable to form the surface of valve body or the valve body side surface of the finger-like portions so that it has a surface roughness within a specific range in order to make the noise prevention effect more perfect.

Abstract: A piston defines in a cylinder housing a pressure chamber connected to a brake pipe and a fluid supply chamber connected to an oil reservoir. The piston has a recess facing the pressure chamber at one end thereof. A valve member is provided in the recess for making or breaking fluid communication between the pressure chamber and the oil reservoir through the supply chamber. A compression spring is disposed in the recess for urging the valve member into its closed position. A spring retainer is fitted about the end of the piston for holding the spring in the recess. A supporting member is provided in the housing on the opposite side of the pressure chamber from the piston. The valve member is supported by a connecting rod extending axially movably through the spring retainer and the supporting member. A compression spring is connected between the spring retainer and the supporting member for urging the connecting rod in the direction which causes the valve member to open.

Abstract: A sealing member for a master cylinder including outer and inner annular lip portions formed integrally on an annular base portion and an annular rib portion having a length greater than the lip portions.

Abstract: A tandem diaphragm brake booster includes a housing, first and second diaphragms disposed in said housing, a partition wall disposed between said first and second diaphragms within said housing for defining four pressure chambers. The housing is composed of a cup-shaped shell section having a broad cylindrical outer wall and a flange shaped rear shell section. A bead of the first diaphragm is situated between the inner surface of the front sell section and a securing member of the partition wall for defining the first and second chambers. The second diaphragm has inner and outer beads and through-holes at its periphery. The inner bead is compressed between the peripheral edge of the partition wall and the inner surface of the rear shell section and the outer bead is air-tightly secured between both peripheral edges of the front shell section and rear shell section.

Abstract: A fluid pressure servomotor for automotive vehicle brakes embodying a housing provided by assembling two shells, a pressure responsive power wall in the housing, a valve mechanism associated with the power wall and being movable relative thereto to control the differential pressure across the power wall, an actuating member connecting the pedal for manually moving the valve mechanism, and an output member for connecting the power wall to a brake master piston. The shells are assembled by being locked together and can be disassembled and reassembled due to the provision of a mechanism for resiliently restoring a yieldable portion in a locking structure so that the shells are reassembled by a uniting axial movement and a subsequent rotative movement to lock the shells with each other in position against such resiliency.

Abstract: Axially extending guide arms cooperate with the interior surfaces of an annular poppet member in the control valve of a brake booster for centering a resilient poppet member face against a succession of valve seats. The guide arms can be a tube contacting the inner annular poppet surfaces and slidingly engaging the inner periphery of the annular retainer that secures the poppet member to the valve housing. The tube can also be fixed to a plate backing the sealing face. Or, the guide arm can be a tubular extension of the retainer for slidingly engaging the poppet inner annular surfaces.

Abstract: A brake booster for operation in connection with a brake pedal which includes a housing having an inner wall, a diaphragm, an outer rim portion thereof being secured to the inner wall of the housing, and power piston movably disposed in the housing and air-tightly connected to an inner end portion of the diaphragm to thereby divide an interior space of the housing into first and second compartments, the power piston including a central portion composed of resin and a metallic disc member surrounding and connected to the central portion, a control valve mechanism positioned within the power piston for generating a pressure difference between the first and second compartments in response to operation of the brake pedal, and a connecting mechanism for connecting the central portion and the metallic disc member wherein the connecting mechanism includes a flange portion formed on an outer peripheral portion of the central portion of the piston and positioned in front of a radially inner peripheral portion of the m