GB765217A - Improvements in or relating to the projection of settable mixes of building materials to form a coating - Google Patents

Abstract

765,217. Cement guns. WHITLEY MORAN & CO., Ltd. Sept. 7, 1954 [Sept. 11, 1953], No. 25135/53. Class 20(2) [Also in Group XXIX] A method of projecting settable mixes of building materials on to a wall or other surface to form a coating thereon comprises conveying a dry mix to the inlet end 9 of a nozzle 3 by a moving column of air, hydrating the mix by supplying water to the mix at the nozzle and assisting or concentrating the projection of the hydrated mix of an auxiliary air supply at the periphery of the discharge end of the nozzle. The dry mix is withdrawn from a hopper 25, Fig. 3, by a stream of compressed air from a jet tube 37 disposed with its' outlet beneath the bottom opening of the hopper and is forced through a pipe 33 screwthreaded at 35 to receive a hose leading to a nozzle 3, Fig. 7. The jet tube 37 is longitudinally adjustable by means of a control lever 40 to enable the rate of supply of dry mix to be varied. The nozzle 3, which is socketed at the inlet end 9 to receive the hose carrying the dry mix is provided with a main passage 16 through which the mix is projected. Water to hydrate the mix flows from a valve 11 into an annular passage 14 and through radial apertures 15 into the passage 16. At the forward end of the nozzle 3 is provided an axially adjustable muff 17 having an annular recess 19 connected by a branch 20 with an air supply connection 12. The recess 19 is closed by a flange 21 having circumferentially spaced notches 22 serving as apertures through which air fed to the recess 19 is projected forwardly to assist or concentrate the projection of mix. A valve, Fig. 4 (not shown) is provided for supplying air to the hose when work has been finished and after the hose has been disconnected from the pipe 33.