GB476586A - Improvements relating to fluid pressure braking apparatus for railway and like vehicles - Google Patents

Abstract

476,586. Fluid pressure brakes. SIMMONS, A. W., KERSHAW, J. W. G., and WESTINGHOUSE BRAKE & SIGNAL CO., Ltd. June 11, 1936, No. 16344. [Class 103 (i)] In fluid-pressure braking - apparatus for vehicles comprising a blow-down valve operated by a retardation controller so as to effect a reduction of the braking effort when a predetermined retardation of the vehicle is attained, a blow-down interlock circuit is provided which is maintained energized when the driver's brake valve is not in an application position, only so long as the blow-down valve is closed and when de-energized effects an indicating action to render the driver aware of the opening of the valve. In Fig. 1, the blowdown valves 1 on each vehicle of the train and which control communication of the brake cylinder pipes 9 with the atmosphere directly or through pressure retaining valves 11 are operated by solenoids 8 connected to a train-wire 5 normally energized to close the valves through a contact 7 operated by a retardation controller. An interlock train wire 4 connected at 6 to the train-wire 5 at the rear of the vehicle has contacts 3 which are closed by members 2 on the valves 1 when the valves are closed. The wire 4 is thus normally energized but is de-energized and operates an indicator 12 or effects an application of the brakes if the driver's valve is not in an application position or cuts off the power supply, if a valve 1 opens. In Fig. 2, in addition to the arrangement shown in Fig. 1, the system comprises holding valves 13 controlled by a driver's switch 19 through a train-wire 14 together with contact members 15 and contacts 16 included in an interlock train-wire 17. Other interlock contact devices 20 are included in a train-wire 21. The interlock train-wires 4, 17, 21 are all connected at 6 with the blow-down train-wire 5 and are connected respectively to indicating or control devices 12, 18, 22. The interlock contacts 3, 16, 20 may instead be included in a common train-wire. Specification 463,946 is referred to.