Patent GB-466436-A (GB)
Title: Improvements in or relating to hydraulic brakes, more particularly for rail and road vehicles
IPC: F16D57/04
Filed: 1936-02-07
Abstract: 466,436. Hydraulic brakes. VOITH, W., VOITH, H., and VOITH, H., (trading as VOITH, J. M., [Firm of]). Feb. 7, 1936, No. 3817. Convention date, Feb. 7, 1935. [Class 103 (i)] A hydraulic brake particularly for vehicles, comprises two coaxial blade wheels co-operating with liquid and driven in opposite directions by the device to be braked. The braking action may be regulated by varying the degree of filling of the brake, and it may be combined with a fluid-pressure operated or other friction brake which may be brought into action at low speeds automatically or otherwise. In Fig. 6, one blade wheel 2 is keyed to a vehicle axle 1, the co-operating blade wheel 3 being reversely driven through gearing 9, 10 and a tubular shaft 11<a>. Both wheels may be driven through gearing from the axle or from a driving shaft of the axle. In addition to the rotating blades there may be co-operating stationary blades and as the braking action of such an arrangement is substantially less in one direction of,rotation, two such brakes may be coaxially arranged as mirror images of each other to obtain equal braking action in both directions. The braking action may be regulated by varying the degree of filling of the brake and this may be effected by admitting compressed air to the reservoir 45 of the brake. The manner in which the degree of filling may be rendered dependent upon the speed or the braking torque is indicated in Fig. 6, in which a piston 44 controls a valve by which compressed air is supplied from a pipe 46 to the reservoir 45. The piston 44 may be acted upon by a speed governor 53, by the liquid pressure in the brake through a piston 50 or by the braking torque through a casing 41 in which the gearing 9, 10 is mounted and which is rockable about the axle 1 against the action of a spring 12 and moving the piston 44 by arm 12<a> and lever 58. The pressure in the reservoir 45 may also be controlled manually by a lever 57. Fig. 7 indicates means by which the hydraulic brake may be supplemented by a fluid-pressure operated friction brake comprising a brake block 80 and operating cylinder 77. The blade wheel 2 is keyed to the shaft 18 driven from the axle 1 and the blade wheel 3 is reversely driven through gearing 21, 22. The degree of filling of the hydraulic brake and the pressure applied to the friction brake is controlled by compressed air supplied to the reservoir 72 and cylinder 77 from pipe 75 and a valve 73. The valve may be operated by pedal 82 or a speed governor 53 through a piston 69 and rod 84 so that when the speed is above a certain value only the hydraulic brake is effective, the friction brake being supplied when the speed has fallen below this value. Control by the speed may alternatively be effected by a pressure-producing wheel 67 driven by the shaft 18. Control may also be effected by the pressure prevailing in the hydraulic brake by a scoop tube disposed in the brake and transmitting the pressure to the piston 69 or by the torque of the hydraulic brake transmitted from the pivot member 24 of the gears 22 through levers 12a. The brake 2, 3 may be cooled by circulating liquid from a jacket 60 surrounding the brake through a cooler 63 by a pump 62. The friction brake may be cooled by the operating liquid of the hydraulic brake.