Patent GB-191124387-A (GB)
Title: Improvements relating to Fluid Pressure Braking Apparatus.
Inventor: CLOUD JOHN WILLS
IPC: B60T15/30
Filed: 1911-11-02
Granted: 1912-10-31
Abstract: 24,387. Cloud, J. W. Nov. 2. Fluid-pressure. - In fluid - pressure braking- apparatus of the kind provided with means for reducing the rate of flow to the brake cylinder when a certain brake-cylinder pressure is obtained, means are provided for readily and manually adjusting the apparatus so as to obtain the restriction of flow at varying brakecylinder pressures, and also to obtain varying degrees of restrictions, to suit different speeds of the train and loads. Figs. 1 and 2 show the invention applied to one form of triple valve, two different sections of the slide valve being shown in the release position. When an application is made, the train-pipe 1, Fig. 1, vents by means of a passage 11, cavity 8, and passage 12 into a chamber 17, and the auxiliary reservoir supplies the brake cylinder by way of the graduating-valve 4, passages 10, 14, 18, Fig. 2, regulating-valve 19, Fig. 1, and passage 24. The valve 19 is held open by a piston 20 pressed by a spring 21, so that when a certain brake-cylinder pressure is obtained, dependent on the adjustment of the spring 21, the piston 20 is moved downwards, and the valve 19 closes more or less so as to cut off or restrict the supply of pressure. The spring 21, and the amount by which the valve 19 is allowed to close, are adjusted by a cam-lever 23, which engages an abutment 22. In a modified form of regulating-valve, the abutment 22 is fixed as to downward movement, and the lever 23, instead of engaging the abutment, acts as a stop to limit the downward movement of the piston 20, and therefore the amount of closing of the valve 19; moreover, a restricted by-pass may be formed to allow the supply to the brake cylinder to continue when the valve is completely closed. Fig. 9 shows another form of triple valve, in which, during an application, air passes from the auxiliary reservoir and, train-pipe by ports 29, 11 respectively into the cavity 8, and thence, by a port 28, regulating- valve 19, and port 24, to the brake cylinder, until the brake-cylinder pressure is sufficient to close the valve 19 and cut off the supply. Air continues to flow to the brake cylinder, however, from the auxiliary reservoir by means of the graduating-valve 4 and ports 16, 30, the restriction of the latter port being adjustable by means of a cock 31. The spring 21 is adjusted by a nut 32. In a modification of this form, the cock 31 may be arranged to control both of the ports 24, 30. In the form shown in Figs. 14 and 15, the triple valve is provided with an auxiliary piston 34, the space 33 below which communicates with the brake cylinder 56, Fig. 15, by way of a regulating-valve 46 controlled by differential pistons 48, 49 and an adjustable spring 21. In an application of the brakes, air passes from the auxiliary reservoir to a port 43, Fig. 14, and forces down the piston 34, thereby opening a local-venting valve 35, so that air flows from the train-pipe 1 past the valve 35 and, joining with air coming from the auxiliary reservoir through a port 38 in the piston 34, passes by way of the regulating- valve and ports 47, 53, 54, Fig. 15, to the brake cylinder. The valve 46 is moved to cut off this supply when a certain pressure is obtained in the brake cylinder. Air continues. however, to flow to the brake cylinder from the auxiliary reservoir by way of ports 42, 45, Fig. 14, the latter of which may be fitted with a controlling-cock similar to the cock 31, Fig. 9. In another form of triple valve fitted with a regulating-valve similar to that shown in Fig. 15, in emergency applications only, and not in moderate applications, the train-pipe vents to the brake cylinder by way of passages in the main slide valve and the regulating- valve. The abutment 22, Fig. 15, of the spring 21 may also be constructed to act as a stop to limit the downward movement of the pistons 48, 49 and therefore the amount of closing of the valve 46, and in this case the spring 21 may be omitted. Fig. 24 shows the application of the invention to an ' ordinary ' triple valve. In an application of the brakes, air flows from the auxiliary reservoir at 2 to the brake cylinder by way of ports 10, 69, 78, regulating-valve 72, and ports 79, 80. The amount of closing of the valve 72 at a certain brake-cylinder pressure is regulated by means of an eccentricallymounted member 76; or the valve 72 is allowed to close completely, and an additional supply passage to the brake cylinder is provided and controlled by a regulating-cock. The valve 72 may also be formed with a by-pass 73.