GB895329A - Improvements relating to vigilance control apparatus for automotive railway vehicles - Google Patents

Abstract

895,329. Fluid-pressure brakes. WESTING- HOUSE BRAKE & SIGNAL CO. Ltd. Oct. 23, 1958 [Oct. 23, 1957], No. 33087/57. Addition to 856,053. Class 103 (1). In a vigilance control apparatus for automotive rail vehicles as described in the parent Specification the pressure switches controlling the changeover from charging to discharging of the timing reservoir, the operation of the warning device, and brake application, are combined into a single switch in the present Specification. For initial charging, master switches MK are closed to energize relay 9 to close contacts 11, push-button 8 being then pressed to energize a relay 3 via contacts 11 to close contacts 12, the relay 9 being slowly released to open contacts 11 only after contacts 12 are closed. The contacts A of the combined pressure-switch 4 are closed and on closing of contacts 12 a valve 2 is energized to charge reservoir 1 from pressure-line 14. As the pressure increases in reservoir 1, contacts C are closed to energize a relay 6 to energize electro-vacuum valve 7 to evacuate the vacuum braking apparatus and train pipe 15, the contacts B and C close momentarily to operate alarm bell 13, and contacts A are then opened, causing contacts 12 to open to de-energize valve 2 to open reservoir 1 to atmosphere via choke 10. The pressure falls at a predetermined rate, causing at a certain pressure the closure of contacts B and C to operate bell 13 and if pushbutton 8 is not pressed to recharge reservoir 1 as above, the pressure continues to fall until contacts C are opened to de-energize relay 6 which in turn de-energizes valve 7 to cause automatic brake application, the opening of contacts C also stopping bell 13. The emergency valves 7 on other vehicles are operated through jumper connection 16. The brakes may be compressed air or vacuum brakes.