GB695373A - Improvements in and relating to pneumatic spray devices for distributing powder - Google Patents

Abstract

695,373. Printing processes. AEROSTYLE, Ltd. Sept. 18, 1951 [June 29,1950], No. 16320/50. Class 100(ii) Set-off preventing.-A pneumatic spray device, e.g. for spraying anti set-off powder on to newly printed sheets, comprises a spray gun 6 rotatably mounted about an axis 7 intersecting the spraying direction and associated with a pneumatic motor adapted to rotate the gun about the axis 7, the arrangement being such that on the application of pressure air to the gun a rotary motion is imparted thereto in one direction. In the embodiment shown in Fig. 1 the gun 6 is rotatably mounted on the supporting axis 7 through which an air feed pipe 8 is passed. The gun 6 is provided with a spigot joumaled in a bearing 10 secured to the support 7. The pneumatic motor comprises a cylinder 11 and piston 12 provided with an extension 13 carrying a grooved roller 14. The roller 14 bears against a fixed curved track 15 having an operative surface eccentric to the rotary axis of the gun and secured to the support 7. The track is provided with stops limiting rotary movement of the gun and cylinder 11 when pressure is applied to the gun and cylinder (Fig. 2 not shown). Return movement of the gun is effected by a spring 18. In a further embodiment, Figs. 3 and 5, the cylinder 11 is mounted parallel with the support 7 the piston extension 13 being pivoted at its end to a link 24 carrying two rollers 26, one co-operating with a fixed helical track 27, and the other with a straight track 28 mounted on the gun body. Movement of the piston extension 13 thereby imparts rotary motion to the gun in one direction the return movement being effected by a torsion spring 30. If desired a single roller 16 may be mounted directly on the extension 13 so as to co-operate with the helical track 27, the straight track, second roller 26 and link 24 being omitted.