Patent GB-110771-A (GB)
Title: Improvements in and relating to Fluid Pressure Brake Systems.
Inventor: TURNER WALTER VICTOR
IPC: B61H11/00
Filed: 1916-08-31
Abstract: 110,771. Turner, W. V., and Cady, W. M. Aug. 31, 1916. Steps.-Fluid-pressure mechanism for actuating the doors and steps or other control means of cars, particularly cars controlled by one man, are combined with the straight and automatic brake system of the car. The door and step &c. mechanism is supplied by way of the emergency brake pipe and the driver's valve and actuation of this mechanism can be effected simultaneously with or independently of the brakes by the driver's valve or by venting the emergency brake pipe with that valve in the normal position. The brake system is of the kind comprising an emergency pipe 7 and a straight pipe 8 connected to the driver's valve 6 and to an emergency valve 1 to which also is connected the reservoir 4. For ordinary straight applications the pipes 7, 8 are connected by the driver's valve and the pressure air is then supplied to the brake cylinder 3 by way of pipe 5, passage 16 in the valve 1, the pipes 7, 8, and passages and cavity 42, 43, 37 in the valve 1. The pipe 7 can be vented to atmosphere either by the driver's valve 6, by a deadman valve 11 of the kind described in Specification 110,888, or otherwise, and the slide of the valve 1 moves to the left to uncover the brake cylinder passage 37 to the valve chamber 15 which communicates with the reservoir 4 by passage 16. Fig. 1 shows one arrangement of door and step mechanism comprising a double piston 17, 18 and rack and pinion 24, 25 maintained in the closed position shown by pressure in the chamber 22 supplied from the brake pipe 7 through the driver's valve 6 and the pipe 23. The chamber 19 is at the same time vented to atmosphere through the pipe 44 and the driver's valve. To move the doors and steps to service position the valve 6 may be operated to vent the pipe 23 and to connect the pipe 20, 44 with the pipe 7, either simultaneously or not with the application of the brakes. The pipe 20 is connected to a double-check valve 41 and when in emergency the pipe 7 is vented a passage 38 in the slide 14 of the valve 1 registers with the passage 39 permitting pressure air to flow from the reservoir 4 by way of the valve chamber 15, the check valve 41 which is moved to the left and the pipe 20 to piston chamber 19. Since moreover the pipes 7 and 23 are connected through the driver's valve, the piston chamber 22 will be exhausted. As shown in Fig. 2 a separate emergency valve 47 is provided for the door and step or other auxiliary device. In the closed position shown pressure air is supplied from reservoir 4 by pipes 7, 58 to the valve piston chamber 48, and past the groove 59 to the valve chamber 50, thence by pipe 54 to the chamber 19 of the actuating cylinder 9. The piston chamber 22 is at the same time exhausted by port 61 by way of pipe 55 and valve cavity 60. Venting of the pipe 7, by venting also the piston valve chamber 48, causes the valve to move to the left, thereby opening the chamber 19 to the exhaust port 61 and the chamber 22 to the valve chamber 50 and reservoir 57, thus moving the doors and steps to service position. The pipe 58 may also be vented to actuate the doors and steps by operation of the driver's valve. In another arrangement, Fig. 3, shown applied to a double-end equipment, a differential piston is employed for actuating the doors and steps. The small piston chamber 67 is constantly connected to the reservoir 4 by pipe 68 and the large piston chamber 64 normally charged by way of the pipe 7, driver's valve and pipe 65 can be exhausted to place the doors and steps in service position either by operation of the driver's valve or by the venting of the pipe 7. In the " handle-off " position of the valve 6 the pipes 7 and 65 are connected by a port 69 to keep the doors &c. in the out-of-service position at the non-operating end of the car except when the pipe 7 is vented. The port 69 is restricted to delay the actuation of the doors &c. until the car has stopped. Fig. 1, shows a switch 33 actuated by a piston 34 subject to the pressure in pipe 7 for cutting off the power in emergency applications of the brakes.