Abstract: A control valve for an automatic parking brake having an inlet for coupling to a source a brake pipe pressure, an outlet for coupling to a control inlet of the automatic parking brake and a pilot for coupling to the source of brake pipe pressure. The control valve is moveable between a first position where the inlet is in communication with the outlet and a second position where the inlet and the outlet are isolated from each other in response to a predetermined amount of brake pipe pressure at the pilot. The control valve includes a spring biasing the control valve into the first position.

Abstract: In a rail vehicle hand brake having a release activated by a pneumatic cylinder, the present control system includes a manual valve having an output connected to a source of pressure at an input when manually activated. A volume is to be charged by the source of pressure. A choke connects the volume to exhaust. The volume and the choke prolong the time the source of pressure is connected to the pneumatic cylinder after the manual valve is activated.

Abstract: A brake control valve includes a housing, a quick braking chamber and a piston subject to brake pipe pressure on one side of the piston. A bore in the housing connects the quick braking chamber via a first port at a first end and the one side of the piston at a second end. The bore has a first portion of a first diameter and a second portion of a second diameter larger than the first diameter. The first bore portion connects the one side of the piston to the second bore portion. A first operator in the bore is connected to the piston. A seal on the first operator is dimensioned to form a seal with the first bore portion and not with the second bore portion. The seal is located on the operator to lie in the first bore portion for a first segment of the range of piston positions and to lie in the second bore portion for a second segment of the range of piston positions.

Abstract: A system for controlling brakes on a rail or light rail motive power unit, in which the brakes are provided with a pneumatic braking system including a pneumatic main pipe and a pneumatic brake pipe. The system includes a control unit, manually operated actuating devices, a relay valve interposed between the pneumatic main pipe and the brake pipe, an electro-pneumatic control unit operable under the control of the unit to supply a variable braking control pressure, pneumatic back-up devices operable under the control of the actuating devices to supply a pneumatic back-up pressure which can be used to control the braking, and an enabling valve which can be switched between a normal operating condition and a back-up operating condition in which it can connect a control inlet of the relay valve selectively to the outlet of the electropneumatic unit or to the back-up devices.

Abstract: A release graduating valve for freight brake control is provided for a railcar having a pneumatic control valve, emergency and auxiliary reservoirs each normally charged with pressurized fluid from a brake pipe and a fluid pressure activated brake cylinder device for applying the brakes on the railcar. A selectively operable release graduating valve can include a graduated release valve and a changeover valve which selectively interposes the graduated release valve to exhaust brake cylinder pressure in a graduated manner responsive to brake pipe pressure. Alternatively, the changeover valve can isolate the graduated release valve and direct the pneumatic control valve to exhaust brake cylinder pressure in a conventional manner. The changeover valve can be operated responsive to the pressure in an air pipe supplied with pressurized fluid from a remote source.

Abstract: A release graduating valve for freight brake control is provided for a railcar having a pneumatic control valve, emergency and auxiliary reservoirs each normally charged with pressurized fluid from a brake pipe and a fluid pressure activated brake cylinder device for applying the brakes on the railcar. A selectively operable release graduating valve can include a graduated release valve and a changeover valve which selectively interposes the graduated release valve to exhaust brake cylinder pressure in a graduated manner responsive to brake pipe pressure. Alternatively, the changeover valve can isolate the graduated release valve and direct the pneumatic control valve to exhaust brake cylinder pressure in a conventional manner. The changeover valve can be operated responsive to the pressure in an air pipe supplied with pressurized fluid from a remote source.

Abstract: An electropneumatic brake control valve unit capable of operating at the interface of the emergency brake portion or the service brake portion of a standard brake control valve as a retrofit unit or operating as a stand alone electropneumatic unit. The unit includes electric valves responsive to electrical signals and sensed brake pipe pressures to operate pneumatic valves to control the brake cylinder. The pneumatic valves are also operable independent of the electric control valves so as to allow braking with the electrical controls off or disabled. The unit can operate in combination with a complete brake control valve or with either or none of its emergency and service portions.

Abstract: An ectropneumatic brake control valve unit capable of operating at the interface of the emergency brake portion or the service brake portion of a standard brake control valve as a retrofit unit or operating as a stand alone electropneumatic unit. The unit includes electric valves responsive to electrical signals and sensed brake pipe pressures to operate pneumatic valves to control the brake cylinder. The pneumatic valves are also operable independent of the electric control valves so as to allow braking with the electrical controls off or disabled. The unit can operate in combination with a complete brake control valve or with either or none of its emergency and service portions.

Abstract: A vent valve made from a standard emergency brake valve portion. It includes an emergency portion body with an interface to be mated with the emergency portion interface of the pipe bracket. The body includes a casting with at least one cover and the casting including all the cast cavities and passages for an emergency portion. A vent valve selectively connects a first brake pipe port to a vent port on the body, A vent piston controls the vent valve and a discharge valve pneumatically controls the vent piston. An emergency piston is responsive to brake pipe pressure for controlling the discharge valve. The body does not include at least one of an in shot valve and an accelerated application valve.

Abstract: An electropneumatic brake control valve unit capable of operating at the interface of the emergency brake portion or the service brake portion of a standard brake control valve as a retrofit unit or operating as a stand alone electropneumatic unit. The unit includes electric valves responsive to electrical signals and sensed brake pipe pressures to operate pneumatic valves to control the brake cylinder. The pneumatic valves are also operable independent of the electric control valves so as to allow braking with the electrical controls off or disabled. The unit can operate in combination with a complete brake control valve or with either or none of its emergency and service portions.

Abstract: An electropneumatic brake control valve unit capable of operating at the interface of the emergency brake portion or the service brake portion of a standard brake control valve as a retrofit unit or operating as a stand alone electropneumatic unit. The unit includes electric valves responsive to electrical signals and sensed brake pipe pressures to operate pneumatic valves to control the brake cylinder. The pneumatic valves are also operable independent of the electric control valves so as to allow braking with the electrical controls off or disabled. The unit can operate in combination with a complete brake control valve or with either or none of its emergency and service portions.

Abstract: An adaptor or retrofit unit which is placeable between a pipe bracket and the service portion of a brake control valve which includes brake pipe passage, brake cylinder passage, auxiliary reservoir passage, emergency reservoir passage and an exhaust retainer passage which interconnects the corresponding ports of the pipe bracket and the service brake portion and electrically controlled valves. A first electrically controlled valve selectively controls the connection of the brake pipe passage to a venting port for applying the brakes. A second electrically controlled valve interconnects the brake pipe passage and the emergency reservoir passage for release of the brakes. A third electrically controlled valve selectively connects the auxiliary reservoir to a vent port for releasing a stuck brake. A fourth electrically controlled valve selectively controls the exhaust passage connected to the retainer for gradually releasing the brake.

Abstract: A pilot mechanism for improving operation of various functions of the pneumatic brake of a train. The mechanism includes solenoid valves, controllable by either a radio/battery mode of operation or a train wire system mode of operation. The solenoid valves can be interposed in various passages in fluid communication with passages of a conventional ABD control valve, as modified to enable operation of the invention, to permit substantially immediate venting of air in those passages to atmosphere.

Abstract: A single sided control valve wherein the service portion is mounted to the front face of a pipe bracket adjacent to the right face and the emergency portion is mounted to the front face adjacent to the left face. The brake pipe, brake cylinder and at least one reservoir port are on the back face and the brake pipe port is adjacent to the left face behind the emergency portion. Mounting brackets each include a horizontal flange with apertures to receive the fasteners which mount the mounting brackets to the vehicle and the horizontal flange which extends from the pipe bracket substantially past the front face and the center of gravity of the control valve. A combined dirt collector and cut-off cock is connected to the brake pipe port adjacent to the left face of the pipe bracket and includes a handle to the left of the left face.

Abstract: A control valve is mounted to a pipe bracket which also includes a manual release valve and an emergency vent valve. The control valve operates with a single reservoir to perform service and emergency brake applications. A pair of interrelated pistons responsive to brake cylinder pressure, brake pipe pressure and control volume pressure operate a supply valve, a quick service valve end exhaust valve to maintain a fixed ratio of brake cylinder pressure to brake pipe pressure reduction. Quick service volume is continuously vented and appropriate valving is provided to allow plural sequential quick service operations. Structures provided to operate the piston stack so as to initially allow graduated brake release and subsequent direct brake release over the brake releasing range. An accelerated emergency release mechanism is also provided. The supply reservoir is only charged during the direct release mode.

Abstract: The electropneumatic control system for the pressure in the main air pipe (37) of compressed air brakes of rail cars is provided with one inlet and one outlet solenoid valve (3 and 4) to control the pressure in a control chamber (26) of a relay valve (19). The inlet solenoid valve (3) and the relay valve (19) are supplied with compressed air from a main reservoir pipe (34). The relay valve controlled by the pressure in the control chamber (26) against the pressure in the main air pipe (37) controls the compressed air lead-in and lead-out for the main air pipe (37). To avoid the undesired response of the relay valve (19) to pressure changes elsewhere in the main air pipe (37), the two sides of the piston (20) of the relay valve (19) are closed without any throttling by way of the secondary valve parts (13 or 14) of the two solenoid valves (3 and 4) in the unactuated state of the control system (2).

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 pressure control valve having a pressure fluid inlet chamber connected to a pressure fluid source via a brake valve. A pressure fluid outlet chamber of the pressure control valve communicates with a brake cylinder. The pressure fluid inlet chamber and the pressure fluid outlet chamber can be connected to a control chamber via an inlet valve. The pressure fluid outlet chamber can be connected to the atmosphere via a controllable outlet valve. From the pressure fluid outlet chamber, a first connecting conduit leads to the control chamber of the inlet valve. The first connecting conduit can be monitored by a control valve embodied as a 2/2-way valve. A second connecting conduit, which is always open, is also provided between the control chamber of the inlet valve and the pressure fluid inlet chamber. This conduit exerts a delaying action upon pressure fluid flowing at high speed through it.

Abstract: A graduated release device which includes a valve, for example a check valve, connecting a control valve port and a brake cylinder port which prevents flow from the brake cylinder port to the control valve port. A graduating section controls the valve to produce graduated release of the brake cylinder in response to pressure on the brake cylinder port, brake pipe port and graduating volume port. An automatic mode section controls the valve to produce direct release of the brake cylinder in response to less than a predetermined value of pressure on the supply line port. If it is a two pipe system which includes graduated release, an appropriate pressure will appear on the supply line port and therefore allow the valve to be controlled by the graduating section.

Abstract: A variable load brake control equipment for a road/rail type vehicle comprising variable load brake apparatus located between the auxiliary reservoir and a supplemental volume reservoir in the supply line upstream of the vehicle control valve device. During braking, the auxiliary reservoir pressure and the supplemental volume reservoir pressure combine to provide an unmodulated buildup of brake pressure until the brake pressure reaches a value that varies as a function of the vehicle load. At this point, the variable load valve device operates to isolate the auxiliary reservoir, so that a continued buildup of brake pressure is modulated by reason of the fact that the supplemental volume reservoir alone supplies braking pressure.

Abstract: In a self-lapping type control valve device, a check valve is provided by means of a seal at the interface of the control piston diaphragm and a recess in which the diaphragm is connected to the valve body, the seal being effective to isolate a control chamber on one side of the control piston from a constant pressure chamber on the opposite side when the control piston is actuated in response to a reduction in the control chamber fluid pressure to initiate a brake application. This seal is displaced from a ridge at the opening of the recess with which the diaphragm is also engageable when actuation of the control piston occurs in response to a relatively large reduction of the control chamber pressure.

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: 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: The present invention discloses a maximum pressure control device for the brake cylinder pressure that is to be supplied to a brake cylinder and this device can consist of two separate pressure control devices or be constructed as a unified, reversible pressure control device. The selection of one of the active pressure control devices or changeover of the switchable maximum pressure control device results from a main brake line pressure acting against a spring loaded control piston which, depending on the main brake line pressure, can switch off the pressure control function of the maximum pressure control device for the low (service) or high (emergency) brake cylinder pressure. The control piston when functioning as an actuated cut off device can be mechanically coupled with a pressure control device by means of a stop coupling or pneumatic coupling. As a result, the control piston is not able to exert any negative effect on the control precision of the maximum pressure control device.

Abstract: A pressure control valve for the compressed air brakes of a railway vehicle includes a triple pressure control valve with a constant pressure chamber, a selector valve and a selector reservoir. Upon the occurrence of pressure reductions in the main brake line for service braking, the selector valve selector remains at rest. When stronger pressure reductions in the main brake line occur, the selector valve evacuates the selector reservoir which lags in relation to the main brake line pressure as result of the force exerted by a pre-stressed spring until a specific minimum pressure is attained by a retention valve. In a subsequent brake release, the selector valve will produce a pressure balance between the constant pressure chamber and the selector reservoir to facilitate the brake release process and a balancing or proportioning of the pressure control valve at an optionally reduced normal pressure head in the main brake line.

Abstract: In a brake control valve device for railway vehicles in which a bias spring acts on the piston stack assembly of the valve device, an additional air reservoir and a differential check valve are arranged to assure proper full service brake pressure, when the control valve device is operated in a direct release mode, thereby overcoming the effect of the bias spring in producing a force balance to cause the piston stack assembly to assume a lap condition before full service brake pressure is achieved. The arrangement has no adverse effect when the control valve device is operated in a graduated release mode.

Abstract: A fluid pressure brake control system of the direct release type for a freight locomotive comprises a first pipe bracket having a manually controllable automatic brake valve device connected thereto on one side for governing fluid brake control pressure in a train pipe, and a manually controllable independent brake valve device is connected on another side of the bracket for governing brakes of the locomotive independent of brakes of freight cars in a train. There is a locomotive brake control valve device comprising a second pipe bracket having a service valve portion secured to one side thereof corresponding to a service valve portion such as is conventionally used on freight car control valve devices. A quick release and emergency valve portion is secured to another side of the second pipe bracket for governing emergency brake pressure and for governing independent direct release of brakes of a locomotive in response to actuation of the manually controllable independent brake valve device.

Abstract: This invention relates to a valve assembly for a railway braking system, including a brake cylinder pressure-maintaining valve which, during brake application, takes air from the brake pipe and feeds it into the brake cylinder until it reaches minimum brake pressure. To avoid the need for an extra valve, the brake cylinder pressure-maintaining valve is used as a quick service bulb exhaust valve during brake release and member are provided to ensure that the brake cylinder pressure maintaining valve opens immediately on brake release. Once the brakes have been applied, pressure in the brake cylinder is maintained from the quick service bulb 59. Brake cylinder exhaust pressure taken from a point 124 after the brake cylinder exhaust valve 50, but before the brake cylinder exhaust choke 70, is directed to chamber G above the inshot and brake cylinder-maintaining valve diaphragm 131. Since the pressure in port 124 upstream of the brake cylinder exhaust choke 70 attains a pressure well within 10 p.s.i.

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: An inshot valve device for use with railway brake apparatus of the type employing a brake cylinder in which the chambers formed on opposite sides of the brake cylinder piston serve as storage reservoirs. Braking force is obtained by the venting of air from the storage reservoir chamber on one side of the brake cylinder piston following movement of the piston to brake application position, so that the storage reservoir chamber from which air is vented is reduced to a minimum to conserve air. During an emergency brake application, the air from this storage reservoir chamber is vented via the inshot valve device, which controls the emergency buildup of brake forces in accordance with a predetermined brake force profile. The inshot valve device controls the emergency brake force buildup to follow this predetermined profile irrespective of different brake pipe charges or different service brake applications that may exist at the time of the emergency.

Abstract: A railway vehicle braking system is provided with snow-brake control means operable in freezing temperatures for overriding the normal full brake release condition in a vehicle coasting or traction situation to apply a small brake force for prolonged periods to engage blocks or shoes on the vehicle wheels to reduce icing. The snow brake control means itself includes an override arrangement for, from time-to-time, effecting complete but temporary release of such a snow brake application so as to enable whatever slack adjustment is necessary to thereby insure continued validity of the brakes for a service application despite brake wear resulting from prolonged snow brake application.

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: A quick service valve is proposed for providing continuous quick service in connection with the operation of a direct release triple valve preferably also provided with an emergency portion having a sensitivity valve for providing a bleed of fluid pressure from a quick action chamber to follow the pressure reductions in a brake pipe, the apparatus having a reference pressure input path connected to the quick service chamber, a brake pipe pressure signal input path, a pressure responsive member responsive to a predetermined difference between the brake pipe pressure and the reference pressure to operate a valve to initiate a restricted discharge from the brake pipe to cause a reduction of the reference pressure and consequent reclosure of the valve. The operation is repetitive during continuing reduction of brake pipe pressure at sufficient rate.

Abstract: A brake control valve device, for railway vehicles, embodies an adjustable service brake cylinder limiting valve that may provide any chosen brake cylinder pressure and also an adjustable emergency brake cylinder limiting valve that may provide any selected higher brake cylinder pressure when the control valve device is conditioned for effecting either a direct release of the brakes or a graduated release of the brakes accordingly as a removable selector valve cover member is secured to a ported face formed on the exterior surface of the control valve device in either a direct release or a graduated release position with respect to this ported face.

Abstract: An accelerated release valve is proposed for brake control valves, especially direct release triple valves, the accelerated release being triggered by rapid collapse or discharge of quick service volume pressure at commencement of a brake releasing mode.

Abstract: A two-pressure brake control valve has a service brake portion which is connected to a brake line, an auxiliary reservoir,an emergency reservoir and a brake cylinder. A main piston in the service brake portion is subjected to brake line pressure on one side and on its other side is subjected to pressure in the auxiliary reservoir. An auxiliary piston which has a greater sensitivity of response than the main piston is displaceable on the main piston and has one side subjected to the brake line pressure and its other side subjected to auxiliary reservoir pressure. A release acceleration valve is connected to the brake line and has an actuator in the displacement path of the auxiliary piston so as to be actuated to an open position upon movement of the auxiliary piston in the initial phase of a brake release operation. There is also a filling valve which is actuated in response to movement of the auxiliary piston to connect the emergency reservoir to the auxiliary reservoir during the release operation.

Abstract: A fluid pressure brake system includes electrically actuated application and release valves. Upon brake application, brake control pipe pressure is vented electrically to accelerate application. Upon brake release, supply reservoir pressure is admitted electrically to the brake control pipe to accelerate release. In emergency situations, auxiliary equipment may be operated from the main reservoir pipe, the supply reservoir or the brake pipe, as desired. A novel solenoid-actuated valve is disclosed, which cooperates with unique indicator circuitry to provide a positive, continuous indication of a preceding electrically assisted application or release.

Abstract: A fluid operable brake control valve apparatus is provided which includes a brake cylinder valve for controlling the supply of fluid pressure into and out of a brake cylinder. The valve is operable by a main pressure responsive member moveable in response to changes in pressure when applied to a brake pipe. A quick service valve is operable in response to such a change tending to cause a brake application for connecting a quick service volume to the brake pipe to enhance the change at commencement of an application. An accelerated release valve device is operable in response to release of fluid pressure from the quick service volume to connect a charged accelerated release reservoir to the brake pipe to assist a change of pressure in the brake pipe causing such a release.

Abstract: A brake control valve device, for railway vehicles, embodies means to enable this control valve device to be selectively conditioned for effecting either a direct release of the brakes or a graduated release of the brakes accordingly as a removable selector valve cover member having a ported face is secured to a ported face formed on the exterior surface of the control valve device in either a first or a second position with respect to this ported face on the control valve device.

Abstract: A brake control valve device operated by a reduction in brake pipe pressure on one side of a movable abutment relative to control reservoir pressure on the opposite side embodies in the abutment a control reservoir charging valve mechanism, a filter and a choke arranged in series. The valve mechanism comprises a spring-biased valve slidably mounted in a ported bushing carried by the abutment. Two spaced-apart stops carried on the abutment enable relative movement between the abutment and the valve whereby, in one position of the valve, fluid under pressure may flow from the brake pipe to the control reservoir to effect charging thereof via the ported bushing, a passageway in the valve and the choke, and, in a second position of this valve, this charging communication is closed.

Abstract: A single sided valve wherein the service portion is mounted to the front face of a pipe bracket adjacent to the right face and the emergency portion is mounted to the front face adjacent to the left face. The brake pipe, brake cylinder and at least one reservoir port are on the back face and the brake pipe port is adjacent to the left face behind the emergency portion. Mounting brackets each include a horizontal flange with apertures to receive the fasteners which mount the mounting brackets to the vehicle and the horizontal flange which extends from the pipe bracket substantially past the front face and the center of gravity of the control valve. A combined dirt collector and cut-off cock is connected to the brake pipe port adjacent to the left face of the pipe bracket and includes a handle to the left of the left face.