Cam actuated anti-lock braking system modulator

摘要

An anti-lock braking system (ABS) pressure modulator is provided. The modulator includes a frame with a bore fluidly exposed to master cylinder and wheel cylinder connections and a check valve for preventing fluid communication from the master cylinder connection to the wheel cylinder connection vi the bore. A piston is slidably mounted within the bore and has a predetermined extreme position at which a stem of the piston opens the check valve. A power device is actuated by an ABS controller. A cam, moved by the power device, has a cam surface. The position of the piston is determined by the cam. A cam follower roller is connected with the piston to in contact with the cam surface. A one-way brake prevents rotation of the roller when the cam moves in one rotational direction to allow the piston to move away from the predetermined extreme position, but allowing the roller to roll over the cam surface when the cam moves in the opposite direction to move the piston toward the predetermined extreme position.