Abstract: Passenger rail vehicle brake control valve apparatus includes, a control valve device of the type limited to direct release of the brakes, having service, emergency, and continuous quick service portions secured to a pipe bracket, and a graduated release valve portion governed jointly by brake cylinder pressure, brake cylinder exhaust passage pressure from the control valve device, and brake pipe pressure to at times modify output of the control valve device to provide for graduated control of the passenger rail vehicle brakes.

Abstract: A protection valve device for a spring parking brake control system has a pipe bracket for connection in a normally pressurized brake pipe, the pipe bracket having connected thereto a protection valve, a charging reset valve and a charging check valve. The protection valve has a chamber at one side of a piston normally pressurized by pressure at a spring parking brake cylinder port and monitors the spring parking brake cylinder pressure to vent fluid from the brake pipe to automatically cause an emergency brake application if such pressure indicates a spring parking brake is applied. The charging reset valve prevents the venting of brake pipe fluid during charging of the brake pipe and spring parking brake system.