GB1476483A - Spray gun - Google Patents

Abstract

1476483 Spray guns UPJOHN CO 5 Aug, 1974 [27 Aug 1973] 34406/74 Heading B2F A spray gun for admixing reactive liquids and discharging the mixture as a spray, comprises a body 12, Fig. 1, including two blocks 14, 16 which are secured together and abut at a plane A-A, one block carrying a handle 18, the other block carrying on the exposed forward face a discharge nozzle 26 with its axis substantially perpendicular to the plane A-A, the body 12 further comprising a mixing chamber 82, Fig. 3, communicating with the atmosphere through the nozzle 26, and ducts for separately receiving the liquids from an external source and conducting them to the mixing chamber (only one duct shown in Fig. 3, 34, 70, 76, 80), the plane A-A intersecting each liquid duct, said one block being counterbored in its abutting face coaxially with the ducts to provide flow control. Valve chambers 36 (only one shown) a control valve being disposed in each chamber and said valves being interconnected to open and close the valve chambers 36. Body blocks 14, 16 are preferably aluminium alloy castings. Each control valve comprises a ball member 40 with a bore (46), Figs. 8, 9 (not shown), extending through to form ports (48), means for rotating the ball such as a shaft 56, Fig. 1, in a socket (54), and a pair of annular seals 42. The shafts 56 may be interconnected by a yoke arm 60 forming the upper end of a trigger 24 which is biased away from handle 18 by a spring (28), Fig. 4 (not shown). Check valves (90), Fig. 7 (not shown), may be located in each duct 76, comprising a hollow sleeve member (92) sealed in duct 76 by O-rings (114, 114') and provided with ports (106, 108) adjacent ducts 70 and 80 respectively. Check balls (98, 98') within member (92) are biased apart by a spring (100), ball (98) acting as a non-return valve to liquid flowing from duct 70 into duct 80. Ball (98') acts as a non-return valve to flushing solvent entering the gun via a nipple 22 and ducting 62, 74, 86 Fig. 3. Flow of solvent is manually controlled by a needle valve 30. In another embodiment, Figs. 10-14 (not shown), the ball members (240) of the flow control valves are interconnected by pinions (253) engaged by reciprocable racks (255) driven by an air actuator (241) of the spring-return type. The solvent control valve (230) is also actuated by compressed air which acts on a piston (263) and is controlled by a thumb button (225). In another embodiment, Figs. 15-19 (not shown), the ball members (340) are interconnected by toggle links (353) and a reciprocable plunger (343) driven by a double-acting air actuator (341).