. Electric railways, theoretically and practically treated . the cylin-der. It will be noticed that the piston shown is of twoparts, a solid rod, and a hollow shaft which receives is to facilitate the application of brakes by handpower, the hand brake chain being attached to the leverconnected to the piston ; and where brakes are operated byhand, the solid piston rod slips easily from the hollow partand it is not necessary to pull out the piston head againstfriction and the retarding spring. The general arrangement of brake cylinders and leversis illustrated in the diagram of Fig. 148,
. Electric railways, theoretically and practically treated . the cylin-der. It will be noticed that the piston shown is of twoparts, a solid rod, and a hollow shaft which receives is to facilitate the application of brakes by handpower, the hand brake chain being attached to the leverconnected to the piston ; and where brakes are operated byhand, the solid piston rod slips easily from the hollow partand it is not necessary to pull out the piston head againstfriction and the retarding spring. The general arrangement of brake cylinders and leversis illustrated in the diagram of Fig. 148, together with theattachment to the hand brake staff. 244 ELECTRIC RAILWAYS. A detailed drawing of the levers shown in Fig. 148 isgiven in Fig. 149 ; this is a form of leverage extensively usedwith air brakes on electric cars. Two methods are in use for admitting air to the brakecylinder. 1st. The air from the reservoir is piped to the motor-mans valve, which is so designed that when turned to theposition for applying brakes, the air is admitted to a pipe. Fig. 149.—AIR BRAKE LEVERS. running directly to the brake cylinder. This is known asthe Straight Air system and is adapted to single carsor short trains, but not to long trains because of the timewhich would be required to supply the quantity of airnecessary to fill the brake cylinders. 2d. Air from the reservoirs is admitted to smaller(auxiliary) reservoirs which are connected to the brakecylinders through a special device known as the triplevalve. The operation of these devices is as follows:when the motorman turns his valve to the position allovy^- BRAKES AND BRAKING. 245 ing air from the main reservoir into the train pipe (whichis run continuously tlirough the train, the several cars be-ing connected by flexible hose couplings), the triple valvespermit the air to flow into the auxiliary reservoirs ; whenthe motorman moves his valves to the position for apply-ing brakes, air is permitted to escape from the train pipeand
Size: 2035px × 1228px
Photo credit: © Reading Room 2020 / Alamy / Afripics
License: Licensed
Model Released: No
Keywords: ., bookcentury1900, bookdecade1900, bookpublishernewyorkvannostrand
