摘要:
The disclosure relates to a fluidically controlled pressure switching valve for a vehicle brake system including a valve chamber, which is arranged in a valve interior and into which an inlet opening and an outlet opening open, and a valve closing body, which is movable in the valve interior and which comprises a piston, defining a first piston surface and a second piston surface, and including a closing element. The valve closing body is movable in accordance with a pressure difference between a pressure acting on the first piston surface and a pressure acting on the second piston surface, against the force of a setting spring arranged in the valve interior, between a closed position, in which a fluid connection between the inlet opening and the outlet opening is interrupted, and an open position, in which the fluid connection between the inlet opening and the outlet opening is open.
摘要:
A pneumatic pressure control valve for a brake control system of a rail vehicle having at least three pressure chambers supplied with compressed air and are disposed in a housing of the pressure control valve, a first pressure chamber sealed by a piston and by a valve seat arranged on a tappet, subjected to a braking pressure and fluidically connected to a second pressure chamber via a conduit in the tappet to relieve pressure, a further third pressure chamber supplied with a supply pressure, arranged between the two pressure chambers and the sealing between the third pressure chamber and the second pressure chamber is achieved by a flat membrane arranged in the third pressure chamber and which enables the tappet to be axially displaced, the flat membrane has a circular opening arranged substantially centrally to provide a check function and through which the tappet extends in the axial direction.
摘要:
A combined spring brake modulating relay valve integrates the functions of a relay valve and a modulating valve. The housing includes a valve assembly movable in response to air pressure provided to selected ports in the housing. A relay piston selectively communicates with a control port and a primary brake circuit port. A modulating piston includes surfaces selectively pressurized by the primary brake circuit port and a secondary brake circuit port. This modulates the pressure from the delivery port to thereby selectively apply the associated spring brakes if a failure is detected at the primary brake circuit port. The exhaust member selectively controls communication between the supply and delivery ports as necessary.
摘要:
A combined spring brake modulating relay valve integrates the functions of a relay valve and a modulating valve. The housing includes a valve assembly movable in response to air pressure provided to selected ports in the housing. A relay piston selectively communicates with a control port and a primary brake circuit port. A modulating piston includes surfaces selectively pressurized by the primary brake circuit port and a secondary brake circuit port. This modulates the pressure from the delivery port to thereby selectively apply the associated spring brakes if a failure is detected at the primary brake circuit port. The exhaust member selectively controls communication between the supply and delivery ports as necessary.
摘要:
A combined spring brake modulating relay valve integrates the functions of a relay valve and a modulating valve. The housing includes a valve assembly movable in response to air pressure provided to selected ports in the housing. A relay piston selectively communicates with a control port and a primary brake circuit port. A modulating piston includes surfaces selectively pressurized by the primary brake circuit port and a secondary brake circuit port. This modulates the pressure from the delivery port to thereby selectively apply the associated spring brakes if a failure is detected at the primary brake circuit port. The exhaust member selectively controls communication between the supply and delivery ports as necessary.
摘要:
A braking system is able to meet emergency stopping distance requirements associated with a failed rear axle service control line by modifying the service relay valve. The service relay valve incorporates a biased double check valve so that an additional or secondary control line from the foot control valve communicates with the service port of the relay valve. If the primary circuit is operational, a biasing force imposed on the double check valve permits normal operation via the primary service line. On the other hand, if the primary service line is lost, the biasing force is overcome and communication between the secondary service line and the service port of the relay valve is established.
摘要:
A railway locomotive brake control system that substitutes a part of a standard freight car brake control valve and interconnected pilot valves and other readily available components to provide the operating functions of the usual specially designed freight locomotive brake valve at a reduced cost. Systems without and with types I or II dynamic brake interlocks are illustrated.
摘要:
A brake control apparatus for railway cars having sprung and unsprung portions is interposed between a brake pressure supply line and a brake cylinder line. A first chamber is connected to the brake pressure supply line and a second chamber is connected to the brake cylinder line. The chambers are abutted by surfaces having different cross-sectional areas of a diaphragm which is biased. A first valve responsive to positioning of the diaphragm, and a second valve responsive to positioning of a strut in a strut cylinder, effect first and second predetermined relationships between pressure drop in the brake pressure supply line and pressure drop in the brake cylinder line. The strut cylinder, mounted between the sprung and unsprung portions of the railway car, may be adapted to sense partially loaded as well as fully loaded or unloaded conditions.