Abstract: An accelerated application valve having a cyclic mode of operation during one phase of which a local quick service reduction of brake pipe pressure occurs and a steady state mode of operation during which a continuous local quick service reduction of brake pipe pressure is achieved. The specific mode of operation is dictated by a control signal that varies with the degree of service brake application called for, this control signal being the "breather" pressure at the ABD/ABDW Control Valve emergency portion.

Abstract: A brake control system having a vent valve device in which a control piston is effective to unseat a normally closed vent valve to provide rapid exhaust of brake pipe pressure to either propagate an emergency brake application in response to brake pipe pressure on one side of the piston being reduced at an emergency rate or to initiate an emergency brake application when pressure on the opposite side of the piston is increased by an auxiliary pilot valve connected to a second main reservoir at a higher pressure.

Abstract: Method and apparatus for compensating for transient effects in pneumatically operated air brake system for a railway vehicle. A look up table or experimentally determined second order correction values is stored in a memory. Based on the magnitude of a previous application of the brakes, a correction value is selected from the look up table having a magnitude to compensate for transient errors in the system. The correction value is then diminished by fixed decrements at fixed intervals. Upon a subsequent application of the brakes, the diminished correction value is used to adjust the pressure communicated to braking mechanisms located on the train cars.

Abstract: A penalty brake control system for a railway locomotive in which a first pressure switch controls the venting of the control chamber of a penalty brake application valve. Reset of the penalty brake application valve, following actuation in response to an unsafe operating condition, is achieved by actuating this first pressure switch to effect closure of the control chamber vent path. A second pressure switch actuates this first pressure switch only when two pressure signals are present thereat, the first pressure signal arising when the penalty brake application value is actuated and the second pressure signal arising when the locomotive brake valve handle is moved out of release position, provided the unsafe operating condition has been corrected.

Abstract: A low brake pipe pressure detecting circuit for a railway train is provided in conjunction with a conventional vent valve device typically associated with the locomotive brake valve device to exhaust the train brake pipe pressure and thereby effect an emergency brake application. Conventional pneumatic pilot valve devices are interconnected with the vent valve device to actuate the vent valve device only for a limited duration following which the pilot valves are automatically reset to effect closure of the vent valve device preparatory to recharging brake pipe pressure to obtain a subsequent brake release.

Abstract: A vent valve device having a pair of diaphragm-type piston members forming a pilot chamber therebetween. The one piston controls a vent valve via which brake pipe pressure is vented locally, while the other piston controls a pilot valve a control venting of the pilot chamber. A breather choke between the pilot chamber on one side of the other piston and a control chamber on the opposite side establishes a predetermined pressure differential thereacross only when brake pipe pressure supplied to the pilot chamber is reduced at an emergency rate to thereby actuate the other piston to a position opening the pilot valve. In addition, this other piston operates a cut-off valve to isolate the pilot chamber from brake pipe pressure so that the pilot valve quickly exhausts pilot chamber pressure.

Abstract: A motor driven ball valve may be driven in two modes of operation; those modes are a normal or testing mode and an emergency mode. The ball valve, when in its full open position, has an air passage that allows for the rapid exhaust of air in the air pipe of the air brake system to atmosphere, thereby inducing the emergency application of the brakes. The rotating ball valve assembly is capable of infinite variation between its full closed and its full open positions. Thus, the motor drive, which is remotely controlled, can effectively modulate the reduction in air pressure in the air pipe for a variety of purposes, including normal operation of the brakes and testing the air brake system. The motor drive mechanism may be in a cam, gear, or follower configuration. When an emergency application of the brakes is required, the motor drive mechanism is disengaged to allow a spring or other torsion device to rapidly rotate the ball to full open position, while drawing minimal electrical power.

Abstract: To shift the resonant (peak) hydraulic pressure vibration frequency, caused when hydraulic pressure varies by brake unit torque fluctuations due to worn-away brake rotor for instance, away from the brake shimmy generation range (e.g. 10 to 17 Hz), an auxiliary pipe is additionally connected between a first pipe connecting the master cylinder to the right side hydraulic cylinder and a second pipe connecting the master cylinder to the left side hydraulic cylinder in the vicinity of the two hydraulic cylinders.

Abstract: A feed circuit for feeding a railway train braking system and usable in conjunction with a compressed air system or with a vacuum system, the feed circuit including an air compressor (1) and being characterized in that it further includes a static vacuum pump (14) powered by the compressed air delivered by the compressor.

Abstract: An apparatus and an associated method for charging the brake lines of a train of railway vehicles having an air-actuated braking system utilizes a flow amplifier to reduce the consumption of air during the charging operation.

Abstract: A controller for controlling the increase in fluid brake pressure as a brake is applied irrespective of how rapidly the operator applies the brakes. The controller includes a valve between inlet and outlet ports in a valve body, the valve having opposing faces subjected respectively to pressure at the outlet and pressure in a volume chamber between the valve and a spring loaded piston and connected to the outlet through a restricted orifice. The valve seeks an equilibrium position wherein the rate of rise in pressure at the outlet is controlled and the deceleration of the vehicle is controlled even when the operator applies the brakes at an excessive rate.

Abstract: A brake hose coupling having a locking mechanism and a pressure relief valve for connecting a telemetry unit to the air brake pipe line of a railway train. The locking mechanism positively latches the brake hose coupling to the "glad hand" brake pipe hose coupling and causes the venting of the entrapped pneumatic pressure by the relief valve when the locking mechanism is unlatched.

Abstract: An improved automatic train-line air brake pressure monitoring system includes circuits that emulate an automatic brake valve and cause an automatic brake manifold release whenever a four psi increase in pressure is sensed. The system includes a pressure sensor amplifier (10) which provides a signal proportional to the sensed pressure in a brake pipe. This signal is tracked by a peak hold circuit (12) that stores the peak value of the signal. The output of the sensor amplifier is subtracted from the output of the peak hold circuit in a subtractor (14) to provide a difference signal. The difference signal is tracked by a reduction hold circuit (22) which stores the minimum value of the difference output from the subtractor. An increase in measured pressure from the stored minimum value is compared in a comparator (24) with a reference value representing the four psi level, and when the increased pressure exceeds the reference value, a system reset is generated.

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.

Abstract: An equalizer discharge valve for use on a railroad air brake system includes a valve housing having an equalizer chamber formed therein above a brake pipe chamber and separated by a piston, diaphragm configuration. The diaphragm is sealed on the outer circumference by the connection to the housing and on the inner circumference by the connection to the piston. A connecting passage formed in the piston has a check valve disposed therein such that fluid pressure can only flow from the equalizer chamber to the brake pipe chamber. An exhaust valve, disposed between the brake pipe chamber and an exhaust chamber, vents the brake pipe chamber when opened as corresponds to selected venting of the equalizer chamber fluid pressure. A back pressure chamber and piston configuration is formed above the equalizer chamber such that fluid pressure from the exhaust chamber can be communicated thereto to counterbalance the force on the piston exerted from the brake pipe side during an exhaust operation.

Abstract: An emergency brake control valve and a system incorporating the same that enables the locomotive engineer to remotely initiate emergency braking at the rear or any intermediate car of the train. The system includes a master unit that is constructed so as to be mounted in the locomotive of the train and a remote control unit that is constructed so as to be mounted on one of the cars. Preferably, the remote control unit is mounted on the last car so that emergency braking may be initiated at the rear of the train. Actuation by the engineer of an emergency brake switch (20) produces an output signal that is transmitted by a radio transmitter (22) and received by a radio receiver (24) in the remote control unit. In response to the received signal, an actuator (26) is energized to operate a solenoid valve (28) from a normally closed position to an open position to connect a control port (48) of an emergency brake control valve (30) to atmosphere.

Abstract: Hydraulic vehicle brake comprising a hydraulic accumulator (1), a brake valve adjustment device (4) supplied thereby, and a brake pressure line section (7) to the brake cylinders attached to the latter via an emergency brake valve (6). In the emergency braking position of the emergency brake valve, this connection is broken, and the brake pressure line section is directly connected to the hydraulic accumulator via a nozzle (10) which is bridged by a cylinder (13) in which a piston is sealingly displaceable. A spring (17) biases the piston in the displacement direction to the accumulator side end connection (11) of the cylinder. During emergency braking, the piston (14) first forces an amount of hydraulic medium sufficient for brake application out of the brake cylinder side chamber (16) of the cylinder (13). This is followed by a damped increase in brake pressure through additional supply of hydraulic medium from the hydraulic accumulator (1) through the nozzle (10) into the brake cylinders.

Abstract: A penalty brake application nullification-prevention system for a railroad train in which a bypass circuit is arranged in one embodiment to vent control pressure from the brake pipe cut-off valve of the locomotive brake valve, in order to prevent the engineman form improperly cutting out the brake valve to nullify a penalty brake application, by operating the brake valve cut-out selector valve. In this arrangement, the bypass circuit operates in response to operation of the penalty application valve when an unsafe operating condition of the train arises. In another embodiment, the bypass circuit is arranged to vent brake pipe pressure in parallel with the brake valve, so that, in the event the brake valve cut-out selector valve is improperly operated to nullify a penalty brake application, the penalty application will be initiated by a brake pipe reduction via the bypass circuit.

Abstract: This invention relates to a railway braking system in which a drop in brake pipe pressure calling for brake application initiates a pilot pressure and this pilot pressure is used to operate other valves pneumatically to effect braking. In this system, during the initial part of a brake application, air flows to atmosphere through a pilot exhaust choke. To avoid problems during release of the braking, it is proposed to isolate or restrict this pilot exhaust choke during at least the initial part of the brake application stage. To achieve this, an interlock valve is introduced into a passage between a release ball valve and a pilot exhaust choke. The interlock valve is operated by a diaphragm biassed by a spring and separating two chambers. Brake pipe pressure is applied to the first chamber and auxiliary reservoir pressure to the second chamber. A very small drop in brake pipe pressure closes the valve and cuts off connection between the release ball valve and the pilot exhaust choke.

Abstract: A railroad vehicle brake system in which a four-way valve is used to control air flow in brake pipe sections and to the control valve which controls the air supplied to a brake cylinder. The four-way valve includes a housing and a rotatable operating member in the form of a truncated bolt with air channels therein which member can be rotated so as to selectively interconnect or cut-off the brake pipe sections and the control valve. The member has operating shafts integral with the bolt which extend from opposite sides of the housing. Multi-part seals are disposed in openings in the housing to which the brake pipe sections and the control valve are connected and have portions urged into contact with the bolt.

Abstract: A snow brake control system in which application of the snow brake pressure during release of a normal brake application is withheld for a duration sufficient to assure movement of the vehicle brake apparatus from a brake application position to a release position, to thereby cause automatic slack adjuster action to take place. In one embodiment, operation of a piloted pneumatic valve is delayed by restricting the exhaust of pressure from a volume reservoir via a choke to thereby momentarily withhold the connection of snow brake control pressure to one inlet of a double check valve that is subject at its opposite inlet to normal brake control pressure. The double check valve is effective to connect the predominant one of the pressures at its opposite inlets to a relay valve to produce brake pressure. In a second embodiment, the double check valve is eliminated and the pilot pneumatic valve controls the connection of either snow brake or normal brake control pressure to the relay valve.

Abstract: A safety device for automatically actuating the air brake system for an entire train of railroad cars when any one or more of the cars becomes derailed includes a derail wheel on its own axle attached to the truck frame between the wheels both on the front and rear set of wheels which are nearest to the train line and normally, such derail wheel is spaced slightly above the rail but will engage the ground in a derailment causing it to rotate. A flexible cable is secured at one end to the axle of the derail wheel so as to be windable thereon when such wheel rotates and has its other end preferably connected to the nearest air hose coupling that is attached to a like coupling on an adjacent car. The winding up of the cable on the derail wheel assembly in a derailment acts to pull the air hose coupling loose from its coupling with the air hose on an adjacent car and the resulting breaking of the train line sets the brakes for all cars in the train.

Abstract: A system for preventing damage to cargo shipped in air-ride suspension semi-trailers loaded on railroad flat cars which comprise at least part of a freight train is provided. The system comprises a coupling element connected to the air brake line of the freight train. The coupling element is connected to an air reservoir mounted on the flat car or on the semi-trailer and supplies compressed air to the reservoir from the brake line of the train. The coupling element includes a valve to prevent air from flowing from the train brake line to the air reservoir when the air pressure in the brake line drops below a predetermined safety level to prevent unwanted activation of the train's brakes. The air reservoir is connected to the air line of the semi-trailer and provides compressed air to the air bags which comprise the air suspension system of the semi-trailer.

Abstract: For use in an air brake system for a railroad car having at least three pipe sections, a valve and actuator assembly manually operable from opposite sides of the car for selectively interconnecting the pipe sections, having a valve housing with three ports leading to an interior valve chamber containing a ball element. The ports are adapted for connection to the pipe sections and the ball element is rotatable within the valve chamber about the axis of an operating stem which protrudes to the exterior of the valve housing. The ball element has communicating passages arranged to communicate with the ports in any one of four different combinations depending on the rotative displacement of the ball element. The ports not communicating with ball element passages are closed. An actuator housing is attached to the valve housing and defines an actuator chamber separate from the valve chamber.

Abstract: A rail vehicle braking apparatus which operates with brake control valves on successive vehicles of a train controlled by pressure in a brake pipe extending along the train has warning means responsive to rising brake pipe fluid flow to warn of possible non-released brakes in the train and the warning means being inhibited by a rising fluid pressure-sensing means to prevent an undesired warning due to brake pipe fluid flow during release of the brakes.

Abstract: Brake apparatus for a railway vehicle including a brake cylinder device of the type having a pair of interconnected pistons to which the vehicle brake rigging is connected, the larger piston having a pair of chambers formed on opposite sides in which air is stored, and a control valve device that is operative responsive to a reduction of brake pipe pressure to connect pressure from the one side of the larger piston to a corresponding side of the smaller piston to effect movement of these pistons to a brake application position and concurrently vents pressure in the chamber on the other side of the larger piston. A transfer valve device is provided to interrupt this exhaust of pressure from the chamber on the other side of the piston until the piston has moved to application position so that the chamber volume is minimal and thus renders a minimum amount of air exhaust sufficient to produce brake applying pressure differentials across this larger piston.

Abstract: Brake system for a railroad vehicle in which the angle cocks and cut-off valve are eliminated and supplanted by a single valve assembly in a valve housing positioned at the junction of the brake pipe and branch pipe; the valve element is in the form of a selectively positionable seal support member carried on a shaft which may be operated from a safe position at either side of the vehicle; a positive lock holds the position of the valve element and is designed to discourage vandalism.

Abstract: An automatic brake release valve in the form of a normally open pressure relief venting structure for air operated vehicular brakes and the like, wherein atmospheric air is vented into the closed brake system intermediate the air brake actuating valves and the brake chambers actuated thereby. This venting valve structure relieves any pressure build-up which occurs as a result of brake valve leakage, since any increase in pressure in this part of the system closes the exhaust valves and actuates the brakes. So that normal brake function is maintained, the venting valve structure closes on a predetermined pressure rise. Thus, when the brakes of the vehicle are applied, a limited amount of air will escape from the system, until the predetermined valve closing pressure is reached, and during this air escape period, water condensate is exhausted from the system automatically, while providing maximum brake efficiency.

Abstract: An uncoupling valve for use in rail car brake systems having a pressurized supervisory pipe includes opposed piston motors which hold the valve open long enough to depressurize the supervisory pipe and cause an emergency brake application, when two cars are uncoupled accidentally. On the other hand, the valve includes a controlled source of pressure for overpressurizing one of the piston motors to hold the valve closed to prevent depressurization of the supervisory pipe, when two cars uncoupled intentionally.

Abstract: A control circuit for reducing the output cycle of a compressed air system of a rapid transit car during "lay-over" periods, when only a minimum of compressed air for a parking brake, for example, is needed by the car, by activating a secondary governor set for a low pressure operating range and connected in series with a primary governor, one or the other of the governors being activated by the control circuit responsively to control signals denoting the state of compressed air requirement of the car.

Abstract: A railway air brake pipe pressure gradient reduction arrangement, wherein pressure gradients along the pipe indicative of a brake pipe pressure fall activate a valve arrangement to temporarily vent the pipe and so speed the brake applying pressure reduction. A further valve arrangement is included for inhibiting venting when a pressure gradient is present due to a pressure rise.

Abstract: Apparatus on each vehicle in a train, for effecting a release of an emergency brake application upon a complete stop of the train, comprises a fluid pressure operated brake pipe vent valve device that is supplied with fluid under pressure from a quick action chamber when the emergency brake application is effected, a release valve device operable upon the release of fluid under pressure therefrom to vent fluid under pressure from the brake pipe vent valve device to atmosphere to cause closing of the brake pipe vent valve thereby enabling recharging of the brake pipe to effect a release of the prior emergency brake application, and a speed responsive device for supplying fluid to the release valve device at a pressure proportional to the speed of the train.

Abstract: A train braking system is provided which operates conventionally to effect braking by a reduction of pressure in a brake pipe and which includes on a car of the train a fluid flow sensor operating in response to a pressure gradient due to flow over a length of the brake pipe in the car or over an interposed restriction in the brake pipe, the fluid flow sensor being sensitive to such flow to operate a valve via which fluid is permitted to be applied to or removed from the brake pipe ahead of the restriction or brake pipe section having regard to the direction of propagation to tend to enhance a pressure change being caused by the flow.

Abstract: The pressure in an air line in an air braking system for a railway vehicle is controlled by an operator's brake valve which is also constructed to maintain the pressure therein. A pressure monitor is responsive to the pressure drop across a restrictor in the air line or in a supply line leading from a source of compressed air. A control line is connected to an energy source through a shut-off device operable by the pressure monitor and through a two-position switch to be connected to a monitor device for brake release operation or to a second monitor device for the flow of air in the air line caused by defects or application of the emergency brake. The shut-off switch will move to the energy passing position only when a certain pressure difference in the restrictor is excceded. The two-position switch is actuated by the operator's brake valve and connects the brake release monitor device to the control line only when the operator's brake valve is in its brake release position.

Abstract: An air brake system for a railway vehicle has a brake control valve connected to a main air line which is maintained at a certain pressure when the brakes are released. Connected to the brake control valve is an air reservoir and a brake cylinder which is connected through suitable linkage to operate a friction brake. A valve device is provided which is actuated in response to the operating state of the friction brake and pressure in the main air line and includes a venting valve connected to the main air line so that the venting valve is opened during a simultaneous occurrence of the brake being in the braking state and the regular pressure level is maintained in the air line. Under other conditions the venting valve is closed.