GB535005A - Improvements in or relating to apparatus for feeding material - Google Patents

Abstract

535,005. Step-by-step conveyers. STEVENS, A. H. (Morse Chain Co.) Feb. 1, 1940, No. 2015. [Class 78 (i)] In a conveyer suitable for feeding solid fuel to a heating stove A, Fig. 1, a conveying screw 13 advances with a non-rotating movement and rotates with an unthreading movement on the return stroke. The screw is actuated by pressure fluid acting alternately on opposite sides of a piston 17 and a pressurerelief valve 90 allows continued operation of the screw in the presence of an obstruction. The screw co-operates with a shearing lip 98 in the feed hopper D exerting against an obstruction a shearing action tending to sever the obstruction and a lateral thrust tending to move the obstruction gradually aside. As shown, the pressure fluid is supplied by a rotary pump 43, Fig. 2, on a shaft 49 driven through belt gearing 60, 61 from a motor 59. The pump draws oil from a sump 69 through a pipe 70 and expels it through a rotary valve 41 and passages 37, 40 alternatively to opposite sides of the piston 17. The valve 41 is rotated intermittently from the shaft 49 through worm gearing 52, 53, Fig. 3, and Geneva mechanism 56, 57. The rod 14 of the piston 17 is squared at 15 to engage a socket 16 on the screw 13 and is provided with a threaded portion 20 engaged by a collar 21. The latter rotates freely on the forward movement of the rod 14 and on the return movement is locked by clutch teeth 29, 30 to a fixed plate 31, causing a rotary unthreading movement of the screw through the fuel. The valve 90 for relieving pressure in the event of obstruction is provided on the duct 62 between the pump 43 and the valve 41, and may serve as a warning signal. The return movement of the piston 17 is terminated by the escape of fluid through a piston-controlled slot 75 in the cylinder 18, and the forward movement by the opening of ports 76 by an extension 80 of the piston rod. The ports 76 are formed in a sleeve 79 secured to an adjustment member 83 screwed on an extension 85 of the cylinder head and graduated to read against a fixed pointer 89. The shearing lip 98 in the hopper is formed on a separate section of tough material, such as a steel forging, detachable for grinding or replacement.