Patent GB-529296-A (GB)
Title: Improvements in or relating to photographic copying apparatus
IPC: G03B27/50
Filed: 1939-06-06
Abstract: 529,296. Photographic copying apparatus. KODAK, Ltd., SMITH, K. S., and LEE, A. E. June 6, 1939, No. 16625. [Class 98 (i)] A photographic copying apparatus employing sensitive material in roll form comprises a rotating drum by which a document to be copied is passed through the field of the camera, means which is capable of being preset according to the number of copies to be produced and which is actuated step by step by the repeated passage of the document through the field of view, and means actuated by it to position guide means in a stripping position to discharge the document from the drum after the predetermined number of copies has been made. In the apparatus shown, the document is carried by a drum 1, through the field of a camera 2, the lens 37 of which is carried by vertically-telescoping tubes 38, 39 and receives the light reflected by an inclined mirror 36 from the document. The drum 1 is covered with cork and provided with perforations 4, and an internal fixed suction chamber 5 in communication with an exhaust fan extends across it at the part within the field of the camera. The document is fed between endless belts 101 and the drum, and each time it passes over the suction chamber, closing the perforations 4, the pressure in the chamber is lowered, causing a flexible diaphragm (not shown) subject to the suction to close a main switch which is in circuit with a solenoid 83, Fig. 4, a lamp 34 for illuminating the document, and a solenoid which operates a clutch (not shown) for transmitting the drive from a shaft 58 to a sprocket shaft which through a chain 62 causes the sensitive paper to be fed through the camera at the requisite speed. The solenoid 83, which is thus energized each time the document passes the suction chamber 5, operates an escapement pawl 77 which allows a ratchet wheel 75 to advance, under the action of a spring 91, one tooth at each actuation. After a predetermined number of actuations of the ratchet wheel, corresponding to its initial setting by a handle 73, a recess in a cam 76 rotating with it comes opposite a cam follower 84 on an arm 85 on a rock-shaft 86. The shaft rocks, causing fingers 92, Fig. 6, carried by it to enter peripheral grooves in the drum 1, so that on its next passage the document is stripped by them from the drum. At the same time, an arm 87 on the shaft 86 releases the arm 88 of a switch 89 in the circuit of the solenoid 83, which is thus not energized during the final passage of the document through the photographic field of the camera. The sensitive paper P passes from a supply spool 25 in a spool-box 20 over a roller 26 into the camera 2, in which it passes successively over a roller 28 through the focal plane F, between a driven feeding roller 28a and pressure roller 29, and between further pressure rollers 30, from which it passes to a take-up spool 33 in a spool-box 21. The feed-roller 28a is driven by gears from a shaft carrying a sprocket wheel over which passes the chain 62, and the take-up spool 33 is driven from the same shaft through chain and sprocket gearing and a slipping clutch. The spool-boxes 20, 21 are detachably secured to the camera 2 by studs 23 engaging in keyhole slots in the side walls of the camera, and carried by vertically movable bars 116 operated by rack and pinions. The rack-bar in the takeup spool-box 21 carries a knife 115 which, when the bar is raised to detach the box, co-operates with a fixed knife 114 to sever the paper strip and also closes the slot through which the paper enters the box. To indicate where the strip is to be cut between the individual copies, the edges are notched at these positions by a toothed cutter 107 which each time the main switch 97 is closed is rotated through one tooth by a ratchet drive operated by a solenoid 121. The camera platform 16 is carried by rollers 17 on a track 18 connected by inclined portions 119 to a lower part 120, so that the camera may be lowered to obtain copies of a smaller size, the lens tube 38 telescoping into the tube 39. At the same time, change-speed gearing operated automatically or manually by a lever 56 decreases the speed at which the sensitive paper is fed to a corresponding extent.