| 摘要 |
972,429. Toothed gearing; fluid-pressure band brakes. W. G. STOECKICHT. Feb. 27, 1963 [March 6, 1962], No. 7921/63. Headings F2E, F2F and F2Q. A brake acting on a rotatably mounted gear train reaction element is automatically released at a predetermined torque. An input pinion 1 drives an output annulus 3 through intermediate gears 2 mounted in a carrier 6 rigid with a brake drum 7e, Fig. 1. Alternatively, the annulus may be carried by the brake drum, the intermediate gear carrier forming the output member. Brake shoes (not shown), on segmental pistons 7a guided in an annular brake cylinder 7 by radial pins 7b, are held against the brake drum 7e by fluid from a pump 22 acting in the annular space S of the brake cylinder. A sealing band 7d prevents fluid leakage from the cylinder. The brake cylinder 7 is held against rotation by springs 21 which at a predetermined torque allow sufficient movement of the cylinder 7 for an arm 18 to trip a switch 26 and move a solenoid-operated valve 25 to vent the fluid system and release the brake. The valve 25 may also be operated manually. In a modification, the springs 21 are replaced by a piston and cylinder arrangement pressurized by fluid from the pump 22. In a further modification, Fig. 5, a check valve 31 is included in the fluid line to the cylinders 27, 28 and a limit switch 32 is tripped by excess pressure in the pipe 34 connecting the cylinders. |
