GB674761A - Photographic contact printing apparatus - Google Patents

Abstract

674,761. Photographic contact-printingapparatus. OZALID CO., Ltd. Nov. 7, 1950 [Sept. 8, 1949], No. 23289/49. Class 98 (ii). An apparatus having a stationary bend or a rotatable cylinder, usually of glass, with an inner light source and an outer traversing means, such as endless tapes, to convey copy material for exposure, is provided with cooling means comprising a tubular duct located on the inside of the bend or cylinder and having air-intake apertures spaced apart in the length of the duct and presented towards the concave surface of the bend, a second tubular duct located on the outside of the bend and having air-intake apertures spaced apart in the length of the bend and presented towards the convex surface of the bend, and a suction device communicating with the interior of the two ducts. Both ducts may extend longitudinally parallel with the cylinder and the inner one may be of approximately D-shaped cross-section having a front wall close to and concentric with the cylinder and a rear wall constituting a reflector. As shown, glass cylinder 10 open at both ends is carried in floating suspension by idler rollers 11, 12 and endless bands 13 rotatable over rollers 14, 15, 16 and 17; copy material is introduced at 18, exposed by mercury vapour lamp 21 which is surrounded and protected by light-filter envelope 22 and which may have end supports 23 as of Specification 662,994, [Group XXXVI], and discharged at 19. Internal duct 24 has openings 34 in its front plate 26 presented to the cylinder 10 and has reflecting back-plate 27, external duct 25 below the cylinder has apertures 36; and both ducts are sealed at one end of the apparatus and connected at the other end to an exhaust fan (not shown).