Abstract: A hydraulic control housing of modular construction consists of a first block, in which a compression chamber is formed, and a second block, which has a port to a reservoir. The compression chamber is connected to the reservoir via a duct extending through the control housing. A check valve is arranged in that duct section of the duct which extends through the first block.

Abstract: A pilot-controlled valve arrangement having at least one valve mechanism mounted in a valve housing for multi-stage switching of a compressed air flow between a feed pressure connection and a working line connection wherein a throttled compressed air flow can be switched in at least one switching stage by a throttle, wherein the pneumatic pilot control has a first control piston mounted in a first control chamber implemented in the valve housing and having a coaxial recess for forming a second control chamber in which a second control piston is mounted, so that an additive control pressure application to the control chambers generates a telescope-like deployment of a ram extending from the second control piston for generating a multi-stage switching stroke for the valve mechanism, in order to implement the throttled compressed air flow in at least one switching stage of the valve mechanism present between the closed and the open valve setting.

Abstract: A brake system is provided for minimizing brake pulsation feedback caused by surface variations of a brake system corner component. The brake system includes at least one sensing device configured to measure a pressure pulse caused by the surface variation of a brake system corner component. A controller module is in communication with the at least one sensing device and a hydraulic brake circuit. The controller module is configured to receive an output from the at least one sensing device and to adjust line pressure in the hydraulic brake circuit to substantially minimize brake pulsation feedback.

Abstract: In a transportation system comprising a fluid carrying brake pipe (14) connecting controlling member of the system and a controlled member (e.g., 12) a method of adaptively disabling an ability of the controlled member to respond to an unexpected brake pipe flow condition includes determining a braking state of the transportation system. The method also includes determining a degree of change in a brake pipe pressure during the braking state. The method further includes disabling an ability of the controlled member to respond to an unexpected brake pipe flow condition for a time period responsive to the braking state and the degree of change in the brake pipe pressure so that an undesired operation of the controlled member is limited.

Abstract: A pneumatically-operated braking system for a tractor-trailer combination incorporates a trailer control valve (4) for providing braking pressure for the trailer. The control valve (4) is adapted to be actuated by a pressure differential acting across it to limit the flow of air in the supply line (2) when a leak is present in the trailer control line (12), and the pressure differential is generated between the pressure in the supply line (2) and pressure supply from another independent source (1).

Abstract: Apparatus for indicating the condition of hand brakes on railway cars and for applying and releasing railway car parking or hand brakes automatically in response to predetermined conditions including movement of a train, wayside conditioning apparatus, wayside operating mechanism, a signal controlled by an operator and performance of predetermined railway operating procedures, such as completion of an air brake test procedure. The apparatus may respond to mechanical, electrical and electronic signals and may operate on pneumatic or electric power provided from the service air brake system of a train or from a source of power outside of such air brake system.

Abstract: An operators's brake valve device for a railway locomotive that is adapted to provide brake pipe recharging in a holding position of the brake valve handle in which the release of brake cylinder pressure is cut off by a release magnet valve device that, in conjunction with an appliction magnet valve device, provides electro-pneumatic control of the train brakes. These magnet valves are controlled electrically via pneumatically piloted electrical switches that receive discrete pressure signals according to the different positions of the brake valve handle.

Abstract: The release device for multiple release compressed air brakes of railborne vehicles comprises a pressure reduction valve (12) which responds in the case of rapid brake applications and optionally of full brake applications, which in order to facilitate the brake release procedure and to accelerate the pressurization of the brake cylinder (13) feeds compressed air from the reference pressure chamber of the triple pressure control valve (2) into the brake cylinder (13). In addition, a sensor valve (25) is provided which, being monitored by an overflow valve (23) which only responds after at least full brake applications having been applied, is adapted to feed brake pressure from the brake cylinder (13) into the main air pipe (1).

Abstract: A vehicle air brake system includes spring set air released parking brakes to which air is supplied through a pressure holding valve which maintains the air chambers of the parking brakes at a predetermined pressure even though the air brake system may be at operating pressures substantially lower than the predetermined pressure. When the air pressure in the air brake system falls below operational levels, the pressure holding valve responds to release the air from the parking brake chambers.

Abstract: A pneumatic vehicle spring parking brake pressure holding valve abruptly seals an atmospheric outlet and enables the valving of brake release air pressure to the spring parking brakes when the vehicle reservoir attains a first pressure. Parking brake release is thus enabled. In the case of loss of air pressure from the system, the pressure holding valve retains the brakes fully released until the vehicle reservoir air pressure drops to a second pressure which is lower than the first. The pressure holding valve thereupon abruptly opens its atmospheric outlet thereby rapidly exhausting the air pressure in the spring parking brakes and setting them.

Abstract: A vehicle fluid pressure braking system is disclosed which includes brake-applying devices having separate service and parking actuators. Separate service and parking actuation circuits are provided to control actuation of the service and parking actuators, respectively. An interlocking valve is provided which prevents release of the parking actuator until a predetermined fluid pressure level is communicated to the service actuator. This interlocking valve prevents inadvertent release of the parking actuators, and also prevents release of the parking actuators in a situation in which a malfunction of the service braking circuit would render operation of the vehicle dangerous.