GB108450A - - Google Patents

Abstract

108,450. Dalton, W. July 18, 1916, [Convention date]. Rotary batch-mixers.-Relates to the manufacture of compounds consisting of a number of powdered ingredients, more particularlv powder used in explosive projectiles. The properly-proportioned powdered ingredients are sifted upon a moving supporting-surface so as to deposit the particles thereon in thin and intimately-mixed layers, the layered deposit being afterwards broken up and the resulting mixture repeatedly relayered. When blending highly-sensitive explosive compounds, the ingredients are sprayed with a liquid such as water or alcohol to thoroughly saturate them and form a non-explosive plastic mixture which can be safely moulded into any desired form. The ingredients are charged in proper proportions into cylindrical receptacles 11 carried by the stationary cover 5 of a rotating hopper 4 having a conical bottom 4<a> which carries a flanged track 3 resting upon conical supporting-rollers 2 on the frame 1. A depending flange 5<a> on the cover 5 dips into an annular water.seal 4<b> on the periphery of the hopper, and flanges 5<b>, 5<f> prevent the escape of dust. The central discharge outlet 4d at the lower end of the hopper is controlled by a valve 6 actuated by a lever 6<a> and rod 6b, and a flange 4d dips into a mercury trough 16 supported by a ring 17 carried by braces 17<a>. The powder receptacles 11 are supported by U-bolts 12 secured to the cover 5, and the sieves 11<a> at the bottoms of the receptacles are agitated by vibrators 13. Cloth shields 11<s> connect the lower ends of the receptacles to the cover 5. The scraper 22 is hinged to a lever 23 pivoted to the flange 5b and is raised or lowered by means of a notched segmental handle 23b. The cleaning-opening 9 in the cover is provided with a removable lid 9<c> having an opening which is connected by a conduit 10<a> to a fan and a dust-separator. The powder is emptied into the receptacle 11 from a can 24 to which an air-operated vibrator 25 is clamped by a ring 26 having a flange to embrace the top of the receptacle 11. A cloth bag 18 or other suitable means attached to the trough 16 leads the mixture to a supplementary blending-apparatus 19, beneath which is a powder can 20, preferably supported on a weighing-scale 20<a>. When the receptacles 11 are emptied, the vibrators 13 are stopped and the vibrator 19a of the blender 19 started. Before raising the valve 6, the powder in the hopper 4 is thoroughly mixed by lowering the scraper 22 and continuing the rotation of the hopper 4. With highly-sensitive powders, liquid is sprayed into the hopper by nozzles connected to a supply pipe 31<a>, and the blender 19 is dispensed with.