Abstract: A system and method for conserving vacuum within a vehicle is described. In one example, vacuum is conserved via limiting volume expansion of a brake booster working chamber.

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: In a distributed power railroad train, an apparatus for equalizing the equalizing reservoir pressure in the remote power unit and the brake pipe pressure. With these pressures equal, the remote unit cannot charge the brake pipe while the lead unit attempts to vent the brake pipe to command a brake application at the railcars of the train.

Abstract: In a distributed power railroad train, an apparatus for equalizing the equalizing reservoir pressure in the remote power unit and the brake pipe pressure in response to airflow into the brake pipe from the remote locomotive. With these pressures equal, the remote unit cannot charge the brake pipe while the lead unit vents the brake pipe to command a brake application at the train railcars.

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: A brake assurance circuit via which a magnet valve device is deenergized to exhaust brake pipe pressure independently of the locomotive brake valve device in order to apply braking any time the proper operating status of the locomotive brake valve is changed after the locomotive is underway. A pressure switch responsive to the cut-in and cut-out setting of the manual selector valve associated with the brake valve senses the locomotive status and connects one of two possible circuits to the magnet valve device in parallel with a primary circuit having a speed responsive switch. Once locomotive movement is underway, the primary circuit drops out and the effective circuits selected by the pressure switch maintains the magnet valve energized provided the selected pressure switch setting is not changed.

Abstract: A brake pipe charging cut-off arrangement for a locomotive air brake in which a rate sensing valve responds to an emergency rate of reduction of brake pipe pressure to vent the control chamber of an actuating valve. This causes the actuating valve to be positioned to connect pressure to the brake pipe cut-off valve of the locomotive brake valve device to interrupt charging of the brake pipe. Following a predetermined time delay of such duration as to assure a complete halt of the train by the resulting emergency brake application, the rate sensing valve automatically resets to terminate venting of the actuating valve control chamber. The actuating valve is then conditioned to be reset on the lead unit by movement of the brake valve handle to emergency position. On a trail unit, a unique arrangement of double check valves sense the proper operating condition of a trail unit brake valve device to automatically reset the actuating valve.

Abstract: This invention relates to locomotive brake control apparatus operable responsively to a reduction of the pressure in a train brake pipe as a result of train separation at a location in the train remote from the locomotive to cause cut off of the locomotive power supply, cut out of dynamic brakes, sanding of the rails, and a service brake application on the entire train.