Abstract: An electro-pneumatic brake control system for a railroad car including application and release solenoid valves having a fail-safe configuration in which full emergency brake pressure is delivered in the event of a power loss due to a train break-in-two for example. The present invention discloses a pressure limiting valve for the purpose of limiting the maximum pressure capable of being delivered in accordance with the existing car load weight sensed by an electric load sensor at the time a bower loss is experienced.

Abstract: A microprocessor based electro-pneumatic brake system for a railroad car including an emergency backup having load control apparatus under control of the microprocessor and arranged to maintain a load setting consistent with the microprocessor control in the event a power failure or malfunction renders the microprocessor inoperable.

Abstract: An electro-pneumatic brake control system for a railroad car including application and release solenoid valves having a fail-safe configuration in which full emergency brake pressure is delivered in the event of a power loss due to a train break-in-two for example. The present invention discloses a pressure limiting valve for the purpose of limiting the maximum pressure capable of being delivered in accordance with the existing car load weight sensed by an electric load sensor at the time a power loss is experienced.

Abstract: A test connector for connecting an air brake test device to access ports of an air brake control valve device where such access ports are normally closed by check valves. A plurality of actuator devices corresponding in number to the access ports are provided in the test connector to unseat the check valves and conduct test air to the test device via central passages in the actuators. The actuators are piston operated in response to a pilot pressure received from a source of compressed air remote from the connector.

Abstract: A fastener assembly for installing valve devices and the like on one side of a mounting plate by bolts where the bolt holes are without threads and the opposite side of the mounting face is inaccessible for holding a bolt head or nut from turning. The fastener assembly includes at least one fastener plate and a minimum of two threaded bolts affixed thereto, so that the threaded portion of the bolts projects through bolt holes in the mounting plate. A retaining washer is threaded onto the projecting bolt threads to retain the fastener plate in place while the valve device is being installed onto the projecting bolt threads on which lock nuts are subsequently screwed to secure the installation.

Abstract: An empty/load changeover valve device for a railway car having a proportioning valve including a valve member via which brake cylinder pressure is supplied and released and a balance piston to which the valve member is connected. The balance piston has equal opposing pressure areas both of which are subject to brake pressure in the "load" setting of the changeover valve device, one of the pressure areas being vented in the "empty" setting, thereby establishing either a non-proportioning mode of brake control or a proportioning mode of brake control. In the "empty" setting, brake supply pressure is connected to an equalizing reservoir. A regulating valve is provided to interrupt this connection until the brake supply pressure reaches a predetermined value, thereby preventing the other pressure area of the balance piston from being unloaded sufficiently to cause an inadvertent opening of the check valve member and a consequent drop in brake cylinder pressure.

Abstract: An empty/load changeover valve device for a railway car having a proportioning valve via which the car control valve supplies brake cylinder pressure. The proportioning valve comprises a balance piston having equal opposing pressure areas and a combined supply and release check valve, one pressure area of the balance piston being subject to air pressure supplied to the brake cylinder under all conditions of loading. The opposing pressure area of the balance piston is either pressurized or depressurized depending upon the car being in an "empty" or "load" condition, thereby establishing either a nonproportioning or a proportioning mode of brake control. Integrating the release check valve with the supply valve so as to have a smaller effective pressure area, the release check valve can be opened with low force to exhaust brake cylinder pressure during brake release, thereby making possible a reduced size empty/load changeover valve device.

Abstract: An empty/load changeover valve for a railway freight car having a proportioning valve via which the car control valve supplies and releases brake cylinder pressure. The proportioning valve comprises a balance piston having equal opposing pressure areas and a check valve integral therewith, one pressure area of the balance piston being subject to air supplied to the brake cylinder under all conditions of car loading. The opposing pressure area is of the balance piston either pressurized or depressurized depending upon the car load condition to accordingly establish a proportional mode of brake control only under empty conditions of vehicle loading. A release control valve is provided to assure release of the brake cylinder pressure in bypass of the proportioning valve check valve, and a lock-out feature prevents car rock and roll from affecting operation of the proportioning valve under empty conditions of car loading.

Abstract: A empty/load changeover valve for a railway freight car having a proportioning valve via which the car control valve supplies and releases brake cylinder pressure. The proportioning valve comprises a balance piston having equal opposing pressure areas and a check valve integral therewith, one pressure area of the balance piston being subject to air supplied to the brake cylinder under all conditions of car loading. The opposing pressure area of the balance piston is either pressurized or depressurized depending upon the car being in a "load" condition or an "empty" condition of loading. This provides for a proportional mode of brake control during "empty" braking in which the brake pressure varies with the actual vehicle load. The arrangement prevents car rock and roll from influencing the proportioned brake pressure and makes provision for assuring release of the brakes in bypass of the proportioning valve.

Abstract: A spring-applied, hydraulic pressure released brake actuator having a modular slack adjuster assembly in which a friction ring is arranged to limit axial movement of a nut member to which a brake shoe is connected, thereby establishing a predetermined brake shoe clearance with a vehicle wheel or brake disc. A spindle that is threadedly engaged with the nut member is connected to the actuator piston by means of a cone clutch that is disengaged during a brake release in the event the return stroke of the piston exceeds the predetermined brake shoe clearance due to brake shoe wear during the preceding brake application. This disengagement of the clutch causes the spindle to be rotated relative to the nut member under the influence of a slack adjuster spring in order to compensate the piston overtravel.

Abstract: A brake actuator having a service brake coupled to an emergency/parking brake through a lost-motion connection that allows the service brake to be applied independently of the emergency/parking brake includes a slack adjuster, the pawl of which is withheld from engagement with the teeth of the slack adjuster ratchet wheel by an interrupter vane whenever the emergency/parking brake is actuated, to thereby disable the slack adjuster.

Abstract: A dual capacity empty/load changeover valve for a railway freight car in which a piston-operated check valve controls the supply of compressed air delivered from the auxilary reservoir to the brake cylinder via the car control valve. The check valve is connected to a balance piston having equal opposing pressure areas, one of which is subject to the air supplied to the brake cylinder under all conditions of car loading. The opposing pressure area of the balance piston is pressurized in a load condition and depressurized in an empty condition, thereby establishing a proportional mode of brake control during empty car braking. A proportioning spring acts on the balance piston to establish the brake cylinder pressure at which the check valve becomes operative to proportion the air supplied to the brake cylinder.

Abstract: A manually-operable pressure-regulating valve device, including a special handle mechanism and a self-lapping valve assembly having a feedback piston on which delivery pressure acts to urge the valve assembly actuating stem in a direction opposite handle pressure, thereby transmitting to the operator a "feel" of the effective delivery pressure. The handle mechanism includes an elongated lever for operating the self-lapping unit with mechanical advantage to reduce operator fatigue. The elongated lever is made flexible, so that movement of the self-lapping valve assembly toward lap position, following actuation thereof, is absorbed by flexure of the elongated lever in order to, in effect, isolate the handle from the self-lapping unit in terms of movement without losing handle "feel" of the delivery pressure acting on the self-lapping valve assembly.

Abstract: An automatic reset arrangement for a manual release mechanism in a spring-applied, air-released brake comprising a sleeve member having axially projecting fingers that slide axially within the bore of the spring piston push rod. The ends of the projecting fingers are formed with outturned lugs having a conically-shaped surface adapted to engage a correspondingly-shaped shoulder in the bore of the piston push rod to provide a drive connection through which the spring brake force is transmitted to the sleeve member. A cylindrical plug member is normally arranged within the sleeve member at the flange end thereof to prevent inward deflection of the fingers and to thus maintain the integrity of the drive connection. A spring-returned, manually operable release lever is arranged to withdraw the plug member when it is desired to release the spring brake in the absence of air.