GB1509827A - Manually operated spray - Google Patents

Abstract

1509827 Spray - producers PLASTIC RESEARCH PRODUCTS INC 13 July 1976 [18 July 1975 5 May 1976] 29149/76 Heading B2F [Also in Division F1] Apparatus for discharging a spray material in a compressed gas carrier comprises a cap 2, Fig. 2A, for mounting on a container for the spray material and having concentric upstanding cylindrical members 3 and 6; a nozzle housing 7 having a laterally directed spray nozzle 5 and an inwardly directed plug 26 surrounded by a depending cylindrical member 11, said nozzle housing being slidably mounted between cylindrical members 3 and 6, thereby defining an air intake chamber 18; a piston comprising a tube 14 and an annular flange 22, said piston being slidably mounted in the cylindrical member 6 such that the lower face of the flange 22 abuts against a compression spring 13 and the upper face, together with the tube 14 and the nozzle housing 7, defines an annular air chamber 19 whose volume varies with movement of the piston; and a valve for controlling the admission of spray material through a dip tube 17 into the internal bore 14b of the tube 14, said valve comprising a valve seat 8e integral with the cap 2 and a movable component comprising a head 10 and a stem 20 slidably mounted in the bore 14b. The upper end of the piston, which fits inside the cylindrical member 11 comprises two concentric annular members 25a and 25b, Fig. 6D, separated by an annular groove, thereby forming a mixing chamber 23 which communicates with the nozzle 5. When the nozzle housing and the piston are depressed, air is forced from the chamber 19 into a channel 16 in the cylindrical member 11 and the pressure of the air deflects the annular member 25a, causing air to be admitted to the mixing chamber 23 where it creates a swirling motion; at the same time the pressure of the spray material in the bore 14b causes the plug 26 to move away from the annular member 25b so that spray material is forced into the mixing chamber 23 where it is atomised by the air and the resulting mist discharged through the nozzle. The blast of compressed air also serves to clear the nozzle orifice. The plug 26 is mounted on a hemispherical diaphragm 27 which is designed to respond to a predetermined pressure of spray material and the plug has a fluted external surface to provide channels for the spray material; alternatively, the inside wall of the annular member 25b may be fluted. Air is supplied to the chamber 19 from the air intake chamber 18, Fig. 2A, through channels 6b in the outer wall of the cylindrical member 6, the chamber 19 being sealed when an inwardly directed bead 7c in the nozzle housing moves below the bottom of the channels 6b. The air intake chamber 18 communicates with the inside of the spray material container through an opening 29 controlled by a diaphragm 28 to equalise the pressures. The nozzle housing 7 has outwardly projecting lugs 7b which engage with flanges (3a), Fig. 3 (not shown) on the cylindrical member 3 for guiding and locking purposes. The valve stem 20 may be of cruciform cross - section so that spray material can flow past it, or may be of circular crosssection. Figs. 5D and 5E (not shown) with a recess (32) which cooperates with a corresponding recess (31) in the piston tube 14 to supply spray material to the bore 14b. In Fig. 9A (not shown) the valve head has a groove (50g) which allows a small proportion of the spray material to leak back into the container. Figs. 7A, 7B, 8A, 8B and 8C (not shown) depiot apparatus similar to that shown in Fig. 2A but with certain minor modifications in the upper end of the piston, the plug, the locking lugs, the valve and the diaphragm for equalising the pressure. The apparatus may be made of plastics material and may be used for spraying liquids, powders or gases.