Patent GB-482020-A (GB)
Title: Improvements in spraying devices
IPC: B05B7/08
Filed: 1937-03-23
Abstract: 482,020. Spray-producers. JENKINS, A. F. March 23, 1937, No. 8558. [Classes 69 (iii) and 135] A spray gun of the kind in which the jet of liquid atomized by compressed air is modified in shape by means of flattening air jets, is provided with means for simultaneously regulating valves controlling the liquid supply, and air supply to the flattening jets independently of the trigger control. Fig. 1 shows an apparatus provided with a spring-pressed air valve 15 and a paint valve 24 controlled by a trigger 16. The air valve delivers air to a passage 45 leading to ports 43, 54 connected to the atomizing nozzle 23 and flattening jets 47 respectively. The passage to the flattening jets is regulated by a needle valve 58 and the travel of the liquid valve limited by a stop 75. The stop 75 is carried by a rod 77 on which is secured a sleeve 65 formed with screw threads 68 engaging a nut 81 carried by the casing. The stem of the valve 58 similarly carries a sleeve 92 threaded at 98 to engage a nut 99. The sleeves 92 and 65 are simultaneously rotated to vary the setting of the stop 75 and valve 54 by links 83, 115 carrying engaging gear wheels 84, 105. The valves may be separately set by turning by means of a key the screwed ends 78, 96 of the rods 63, 60. The gear wheels are turned by a handle 85, Figs. 2 and 3, provided with a spring-pressed pawl 124 engaging detents 123 to hold the gear at the most used positions, a stop 125 being provided at the lowermost position to prevent further' movement of the handle. A scale may be marked on the casing to indicate the amount of opening of the valves. The air supplied to the atomizing jet may be regulated simultaneously with that to the flattening jet by a ring 72, Fig. 6, on the rod 60 co-operating with a ridge 71 on the inside of the passage 48. Fig. 18 shows a modification in which the air supply is regulated by a spring-pressed ball-valve 180 and liquid by a needle valve. The valves are operated by a yoke-shaped trigger 16<1> carrying a bridgepiece 163 similar to that described in Specification 313,122, [Class 69 (iii)], for operating the paint valve and a bridge-piece 185 for operating the air valve. The travel of the liquid valve is determined .by the position of a sleeve 158 the position of which is varied by a pin 159 engaging a helical groove on the valve stem, rotation of which is effected by a gear wheel 202 or by a knurled head 172. Air to the flattening nozzles is regulated by a. sector-shaped valve pressed by a spring 195 and rotated by a rod 189. The valve settings are simultaneously regulated by gearing 202, 203, 204, the central gear 204 being turned by a lever 210, Fig. 19, which may be locked in various positions. The gear wheels may be of different sizes and may be mutilated to permit of limited regulation of one valve when the other is set. The middle gear wheel 209 may be slidably mounted on its journal and pressed in and out of engagement by either a cam 220 and spring 221 or by a lever 210, so that the valves may be independently set. Fig. 29 shows the spray head which comprises a member 226 having a central liquid orifice and main air ports 244, outside which is clamped by a screw cap 227 an outer member provided with a central air nozzle 240, a ring of subsidiary air jets 245 leading to an annulus 242, and the flattening jets 232.