Abstract: A distributor valve for a brake control system of a vehicle is provided with an access interface that includes a plurality of access ports for measuring the operational pressures of the distributor valve. The distributor valve includes a pipe bracket and a main line and main portions mounted on the pipe bracket. The pipe bracket includes a plurality of passages for communicating the main portion and the main line portion with each other and with a brake pipe, brake cylinder, and reservoir of the brake control system. The plurality of access ports of the access interface includes ports in communication with the working chamber passage, valve chamber passage, brake pipe passage, reservoir passage, and the brake cylinder passage of the pipe bracket.

Abstract: A distributor valve for a brake control system of a railway vehicle is provided with an access interface that includes a plurality of access ports for measuring the operational pressures of the distributor valve. The distributor valve includes a pipe bracket and a main line and main portions mounted on the pipe bracket. The pipe bracket includes a plurality of passages for communicating the main portion and the main line portion with each other and with a brake pipe, brake cylinder, and reservoir of the brake control system. The plurality of access ports of the access interface includes ports in communication with the working chamber passage, valve chamber passage, brake pipe passage, reservoir passage, and the brake cylinder passage of the pipe bracket.

Abstract: A service portion of a rail pneumatic brake control valve which includes a piston responsive to pressure differential between brake pipe pressure at a brake pipe port and reservoir pressure at a reservoir port and a first valve controlled by the piston to determine pressure in a brake cylinder for a service application. A stability choke and check valve are connected in series between the brake pipe port and the reservoir port. The check valve permits flow from the brake pipe port to the reservoir port and prevents flow from the reservoir port to the brake pipe port independent of the piston.

Abstract: A backup pneumatic emergency control valve for an electro-pneumatic brake system for a railroad freight car comprising an emergency portion of a standard AB type freight brake control valve device without the service portion.

Abstract: A quick service limiting valve device for a freight brake control valve employing a primary valve in a fluid flow path via which brake pipe air is connected to the brake cylinder during a secondary phase of quick service to propagate the brake pipe reduction signal until the brake cylinder pressure acting on the limiting valve control piston effects closure of the primary valve to terminate the quick service flow of brake pipe air to the brake cylinder when a predetermined brake cylinder limit pressure is realized. A secondary valve is arranged to interrupt the brake pipe to brake cylinder flow path downstream of the primary valve in the event leakage at the primary valve causes the pressure acting on the quick service limiting valve control piston to exceed the predetermined limit pressure.

Abstract: A piston valve assembly for a freight brake control valve device in which axial displacement of a piston member is provided relative to its slide valve in response to slide valve friction creating excessive resistance to movement of the piston assembly from lap to release position. This relative movement between the piston member and slide valve causes a graduating valve that is carried fast with the piston member to open a release insuring passage in the slide valve and thereby exhaust auxiliary reservoir pressure from one side of the piston member. Accordingly, a relatively high pressure differential is created across the piston member to quickly overcome the slide valve resistance and assure prompt movement of the piston valve assembly and thereby obtain brake release without delay.

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: An improved freight brake emergency valve device having improved stability against undesired emergency brake applications, without loss of emergency sensitivity. Flow regulator in the form of a valve and choke combination or a choke itself is employed between the quick action chamber and the chamber normally subject to quick action chamber pressure on the side of the emergency piston opposite brake pipe pressure. This has the effect of momentarily reducing the volume of quick action chamber pressure in order to achieve an intensified pressure reduction in response to initial deflection of the piston member sufficient to counteract a momentary, spurious brake pipe pressure fluctuation.

Abstract: A service valve piston assembly for a freight brake control valve device in which the graduating valve is configured to cooperate with the associated slide valve to close off the application port via which auxiliary reservoir pressure acting on one side of the piston assembly feeds the brake cylinder prior to opening of the stability port via which the brake pipe pressure on the opposite side of the piston assembly is communicated with auxiliary reservoir pressure on the one side of the piston, thereby preventing the piston valve assembly from finding a quasi-lap position in which the brake cylinder continues to be pressurized.

Abstract: A freight brake control valve device for a railway vehicle having a service piston slide valve arranged with a detent to latch the service piston in preliminary quick service position until such time as the application pressure differential acting on the piston exceeds a predetermined value.

Abstract: A continual type quick service valve adapted to be independently mounted on a railway car to provide local, supplemental venting of the car brake pipe pressure, as long as the brake pipe pressure continues to be reduced externally. This quick service venting of the brake pipe pressure is achieved utilizing a single piston actuated exhaust valve that is either cyclically-operated between open and closed states or is held open continuously depending upon the degree of brake application in effect. By selective tuning, the open duration of the exhaust valve can be made to exceed the duration the exhaust valve is closed during each cycle of operation or to remain open for the duration of the external brake pipe pressure reduction to achieve high operating efficiency.

Abstract: The acceleration apparatus for connection with a pilot operated compressed-air brake comprises a tap-off valve which vents the main air line or conduit at the beginning of the braking procedure. This tap-off valve is opened by an actuator or actuating mechanism via a disengageable intermediary member. By employing a rotationally symmetrical plunger or push rod which is pivoted into the operative position thereof by a spring and deflected by an interrupter piston, the construction of the disengageable intermediary member can be substantially simplified. The plunger or push rod possesses at the one end thereof a cam or pin and a substantially conical surface.

Abstract: An improved freight brake emergency valve providing improved stability against undesired emergency brake applications without degradation of emergency sensitiveity by increasing the "breathing" range of travel of the emergency piston to allow a momentary random brake pipe pressure fluctuation to dissipate, and by providing a volumetric chamber between the quick action chamber "breather" port connection at the slide valve/seat interface and the "breather" choke in order to obtain a momentary fast reduction of quick action chamber pressure to counteract a brake pipe pressure fluctuation during pressure equalization between the quick action chamber and the added volumetric chamber.

Abstract: A freight brake control valve device having an improved quick service function provided by suppressing premature cut off operation of the quick service limiting valve. In one embodiment of the invention, this is accomplished by connecting the quick service volume pressure to the underside of the quick service limiting valve piston during preliminary quick service to counteract the pressure pulse on the opposite side of the piston that occurs during the transition between the preliminary and secondary stages of quick service. In a second embodiment, pressure is created at the underside of the quick service limiting valve piston by dashpot action of the piston itself.

Abstract: A fluid brake control system for a railway train has control valves of the ABD type that have service valves that are modified to provide continuous quick service, thus eliminating the need for special accelerated application valves as currently used in ABDW control valves.

Abstract: A freight brake control valve device having an improved quick service function achieved by utilizing a common quick service volume during secondary quick service as well as preliminary quick service, in order to achieve an intensified secondary quick service reduction of brake pipe pressure. Further, a continuing local reduction of break pipe pressure is obtained without any time lag during transition from preliminary to secondary stage quick service. In a first embodiment of the invention, an exhaust passage separate from the brake cylinder exhaust passage is provided to assure venting of the preliminary quick service volume in the event the brake cylinder retainer valve is set up. In a second embodiment, the additional volume is vented via the brake cylinder exhaust passage.

Abstract: A railway car has a brake control equipment group on each truck for governing the brakes thereof including simplified light weight triple valve and reservoir equipment and a modulation equipment group is disposed between trucks of the car providing normal per car requirements for modulating pressure in the brake pipe that would normally be provided by a conventional ABD valve required for each truck equipment group.

Abstract: An electropneumatic brake system for a railway vehicle having an electronic control unit that outputs a friction brake demand signal according to the difference between a brake command signal and a feedback signal representative of the effective dynamic brake, whereby the total dynamic and friction brake effort corresponds to the brake command signal. The brake system also includes a pneumatic operating unit having a pair of high-capacity, electropneumatic valves operated by the friction brake demand signal to regulate the pneumatic pressure at the brake unit directly, that is, without an intermediary relay valve. Such an arrangement provides better response and more accurate pressure feedback of the friction brake level to the electronic control unit. A service rate control choke is located ahead of the electropneumatic valves, which allows these valves to perform the emergency and wheel-slip control functions without requiring independent valves for this purpose, by virtue of their high-capacity capability.

Abstract: An accelerator for control valves, particularly for triple pressure control valves (3) of pneumatic brake systems of rail vehicles, having a pick-up accelerator (30) and a transfer chamber (40) as well as a service brake accelerator (52), the service brake accelerator (52) having a reference pressure chamber (55) which is connected to the transfer chamber (40) of the pick-up accelerator, the transfer chamber having a bleeder nozzle which is not open at all times. As a result, the service brake accelerator (52) is activated only during braking operations, while the reference pressure chamber (55) is protected from filling strokes, the volumes which are in continuous connection with the air main (1) are reduced, and the air consumption is lowered, especially during brake release operations.

Abstract: A service brake accelerator having a line chamber (3) connected to the main air supply line (1) and a reference pressure chamber (6) connected to the line chamber via a nozzle (7). The line chamber is separated from the reference pressure chamber by a diaphragm piston (5) which is biased by a spring (10) against a valve seat (9) projecting into the reference pressure chamber and restricting a nozzle opening (23) to the inner chamber (24) of a second valve seat (20). A second diaphragm piston (17) is biased against this second valve seat by a spring (21). The space (16) surrounding the second valve seat can be connected, partly throttled, via a nozzle (14), to the line chamber by way of a shut-off valve (12, 13) which opens laterally of the reference pressure chamber upon overbalancing pressure upon the first diaphragm piston; this space is always open to atmosphere via a further nozzle (25). The accelerator operates cyclically and has a safe, stable neutral position between its work cycles and rest position.

Abstract: Brake apparatus for a railway vehicle including a brake cylinder device of the type having a pair of interconnected pistons of unequal size to which the vehicle brake rigging is connected. The larger power piston forms an application chamber and a release chamber on its opposite sides in which air is stored for use in controlling the vehicle brakes. The brake apparatus further includes a control valve device that is operative responsive to a reduction of brake pipe pressure to conduct flow of air from the release chamber to a positioning chamber formed on the side of the smaller positioning piston corresponding to the side of the power piston having the application chamber, to effect movement of the interconnected pistons to a brake application position.

Abstract: Brake apparatus for a railway vehicle including a brake cylinder device of the type having a pair of interconnected pistons of unequal size to which the vehicle braking rigging is connected, the larger piston having first and second chambers formed on its opposite sides in which air is stored for use in controlling the vehicle brakes, and a control valve device that is operative responsive to a reduction of brake pipe pressure to transfer air from the first chamber to a third chamber formed on the side of the smaller piston corresponding to the side of the larger piston having the second chamber, to effect movement of the interconnected pistons to a brake application position. As piston displacement occurs, pressure in the second chamber is equalized with the pressure in the third chamber so that no pressure differential is developed across the larger piston, until a predetermined pressure is established in the third chamber consistent with a desired minimum brake application force.

Abstract: A continuous quick service valve arrangement for a direct release brake control system is provided with a sensing valve responsive to reductions of brake pipe pressure in relation to a reference pressure to apply fluid under pressure via a choke to a pulsating device which operates a quick service valve to drive pulses of air out of the brake pipe for as long as the brake pipe pressure continues to reduce for a brake application, the pulsating device is operated by a biassed member which when operated by being displaced in response to attainment of a certain pressure in a volume supplied by the sensing valve presents a greater area to the volume and opens a discharge path for the volume to permit the member to repetitively operate and reset.

Abstract: This invention relates to a railway vehicle continual quick service valve device that embodies two abutments normally subject on their respective opposite sides of the pressure in a train brake pipe and in a control chamber. Upon a reduction of brake pipe pressure on one side of these abutments, one abutment operates a valve to release fluid under pressure from the brake pipe and the brake pipe side of the other abutment to atmosphere whereupon this other abutment operates a valve that releases fluid under pressure from the control chamber and the control chamber side of both abutments to atmosphere. These abutments then operate their respective valves to cut off venting of fluid under pressure from the brake pipe and the control chamber to atmosphere. If the reduction of brake pipe pressure on the one side of the one abutment continues, the abovedescribed cycle reoccurs so long as fluid under pressure is released from the brake pipe.

Abstract: A continuous quick service device is proposed for use in conjunction with a direct release brake controlling triple valve and which, while not interfering with the emergency valve operation, operates by employing quick action chamber air both as a reference against which brake pipe pressure reductions are detected and as a source of air to operate a pressure responsive device in a reciprocating manner to discharge pulses of air from a reducing brake pipe to afford quick service operation of the triple valve both for initial application from a brakes released condition and for subsequent brake pipe pressure reductions giving rise to increased brake applications.

Abstract: An inexpensive emergency valve device embodies a cycling-type continual quick service valve operative by an abutment, subject on its respective opposite sides to the pressure in a train brake pipe and in a quick action chamber, in response to a service rate of reduction of the pressure of the fluid in a train brake pipe to repeatedly vent and supply fluid under pressure from and to a quick service volume disposed on one side of a diaphragm-type valve that is operatively responsive to the venting of fluid under pressure from this volume to effect the release of fluid under pressure from the quick action chamber to atmosphere at a rate faster than a service rate to cause joint cyclic operation of the continual quick service valve and the diaphragm valve to successively supply fluid under pressure from the brake pipe to and thereafter release fluid under pressure from the quick service volume at a certain rate and from the quick action chamber at a faster rate so long as fluid under pressure is released from the

Abstract: A continuous quick service device is proposed for use in conjunction with a direct release brake controlling triple valve and which, while not interfering with the emergency valve operation, operates by employing quick action chamber air both as a reference against which brake pipe pressure reductions are detected and as a source of air to operate a pressure responsive device in a reciprocating manner to discharge pulses of air from a reducing brake pipe to afford quick service operation of the triple valve both for initial application from a brakes released condition and for subsequent brake pipe pressure reductions giving rise to increased brake applications. A relay valve serves to operate the pressure responsive device to provide additional sensitivity.

Abstract: A two-pressure brake control valve for a single stage releasing indirectly acting airbrake particularly for railway vehicles has a service brake portion in which is a main control element to control a valve so as to subject a brake cylinder to the action of air from an auxiliary air reservoir in response to a decrease in pressure in the brake line per unit time below a predetermined value. An emergency brake portion has a main piston as a main control element and an auxiliary piston is mounted on this main piston. The main piston controls a second valve to further subject the brake cylinder to the action of air from an emergency brake reservoir in response to a decrease in pressure in the brake line per unit time exceeding the predetermined value. A service brake accelerator valve is actuated by the auxiliary piston in response to a variation of pressure in the brake line during a service braking operation when the main piston is in an inactive position.

Abstract: This invention relates to a railway vehicle continual quick service valve device that operates in reoccurring cycles so long as fluid under pressure is being released from a train brake pipe by a brake valve device on the locomotive to, upon each cycle, locally release fluid under pressure from the train brake pipe to atmosphere via this valve device on each vehicle.

Abstract: A valve arrangement is provided for giving a continuous quick service facility in a triple valve controlling rail vehicle brakes in response to brake pipe pressure reductions. The arrangement comprises a pressure responsive member which responds to more than a predetermined brake pipe pressure reduction in relation to a reference pressure to operate a pulsator which discharges repetitive pulses of air from the brake pipe for as long as the pressure reduction persists.

Abstract: A service valve portion of a railway vehicle brake control valve device embodies large capacity spool-type brake cylinder application and release piston valves and a small spool-type valve for controlling the supply and release of fluid under pressure to and from the application and release piston valves and also the reservoir charging and quick service features.

Abstract: This invention relates to a cycling-type continual quick service valve device which embodies therein a quick service valve means that comprises two valves each operatively connected to an abutment subject to fluid under pressure supplied from a train brake pipe through a first restriction to a chamber on one side thereof and subject to fluid under pressure supplied from the brake pipe to a chamber at the opposite side and to a quick service chamber via two restrictions arranged in parallel and in series with a third restriction, the sizes of these three restrictions being such that the rate of flow of fluid under pressure therethrough is less than the rate of flow through the first restriction. A check valve is arranged in series with one of the two parallel arranged restrictions so as to prevent flow therethrough in the direction from the chamber at the opposite side of the abutment to the brake pipe.

Abstract: An inexpensve emergency valve device embodies a cycling-type continual quick service valve operative by an abutment, subject on its respective opposite sides to the pressure in a train brake pipe and in a quick action chamber, in response to a service rate of reduction of the pressure of the fluid in a train brake pipe to repeatedly vent and supply fluid under pressure from and to a quick service volume disposed on one side of a diaphragm-type valve that is operatively responsive to the venting of fluid under pressure from this volume to effect the release of fluid under pressure from the quick action chamber to atmosphere at a rate faster than a service rate to cause joint cyclic operation of the continual quick service valve and the diaphragm valve to successively supply fluid under pressure from the brake pipe to and thereafter release fluid under pressure from the quick service volume at a certain rate and from the quick action chamber at a faster rate so long as fluid under pressure is released from the