GB190916828A - Improvements in Air Brake Testing Apparatus. - Google Patents

Abstract

16,828. Dukesmith, F. H. July 19. Brake signals.- In a valve device operated by means of an excess pressure admitted to the train-pipe by t h e engineer for testing and indicating the condition of the train - pipe to ensure that all the angle-cocks on the train are opened, the signal is placed at the rear end of the train and means are provided for silencing the signal after it has been actuated. The device is connected by the couplings 23, 24 to the rear end of the signalpipe 31 and trainpipe 28 respectively. A diaphragm 6, subjected to train-pipe pressure on one side and on the other side to the pressure of an adjustable spring 4, carries a valve 7 closing the port connecting the chambers A, B. The chamber B is in communication with a chamber C in which is mounted a diaphragm 15 secured to a spindle 15‹. A valve 16 is loosely mounted on the upper end of the spindle 15<C> and is held on its seat by a spring 18, thereby closing the opening from the chamber C to the exhaust ports 10<A>. The lower end of the spindle carries a valve 20, which is pressed on its seat by a spring 19 and closes communication between the signal pipe connexion 23 and a whistle 14. When an excess pressure is admitted to the train-pipe by the engineer the diaphragm 6 is raised against the action of the spring 4 and opens the valve 7 admitting air from the train-pipe to the chamber C. The diaphragm 15 is then depressed and the valve 20 is opened to admit air from the signalpipe 31 to the whistle 14. The reduction of pressure in the signal-pipe causes a signal to be operated in the engineer's cab. A stop 17 fixed to the upper end of the diaphragm spindle opens the exhaust valve 16 so that the pressure in the chamber C is reduced allowing the valve 20 to close. The closing of the valve is also assisted by air from the signal-pipe passing through a groove 34 in the spindle 15<C> into the diaphragm chamber D. Leakage ports 32, 33 exhaust the chambers C, D after a test has been made. The train-pipe 28 is also provided with a three-way cock 26 which may be operated manually to sound a whistle 27, or to vent the train-pipe through the port 26B to apply the brakes.