Patent GB-536808-A (GB)
Title: Photographic apparatus for successive photographs arranged in adjacent horizontal rows on the same sensitive surface
IPC: G03B19/02
Filed: 1939-08-31
Abstract: 536,808. Step-and-repeat photographic cameras. BUESS, A., and CUENDET, M. Aug. 31, 1939, No. 25025. Convention date, Sept. 6, 1938. [Class 98 (i)] In a step-and-repeat camera for taking photographs in adjacent horizontal rows, the darkslide holder being displaceable horizontally in a vertically-movable frame, the horizontal movements are produced by the engagement of an operating device with racks on the dark-slide holder, there being one rack for each row of photographs, and the vertical movements are produced by one or more pawls on the frame which co-operate with the operating device. In the form shown, which is intended to take four rows of pictures, a plate 14 having slides (not shown) for attaching the dark-slide carries rollers 15 on which it is movable horizontally in a frame formed of horizontal angle members 8, 9 and vertical bars 10, 11. This frame is vertically-movable on rods 5, 6 which pass through bent ends of the bars 10, 11. Bars 16, 17 on the slide carrier 14 are formed with square-toothed racks 18, 19, 20, 21 on their upper and lower edges, in which engage pins 60, 61 projecting from a disc 57, Fig. 8, on the operating-shaft 50. One turn of the shaft 50 moves the rack through two teeth, corresponding to the horizontal spacing of the photographs. When the traverse from right to left is completed, a pin 28 on the plate 14 engages the tail 36 of a slotted pawl 30 pivoted on the bar 13 and tips it so that a pin 37 carried by it engages the top of a slot 40 in the bar 13. In this position, the pawl is engaged during the next revolution of the shaft 50 by pins 58, 59, so raising the frame into position for taking the first photograph of the succeeding row, in which position it is held by a pawl 44 which engages notches in the side of the bar 13. The pins 60, 61 then engage the second rack 19 and traverse it from left to right, after which a pin 29 on the plate 14 tips a second pawl 32 by which the frame is again raised. The last vertical movement of the frame is produced by a pawl 34 coupled to the pawl 30 by a link 43. The shutter, Fig. 5, comprises a pivoted blade 85 urged to closed position by a spring 88. During rotation of the shaft 50 a cam 62 carried by it operates through a linkage system 64, 66, 67, 72 to rotate a spring-blade lever 75 until an inclined end portion 78a snaps over a pin 87 on the blade 85. The lever 75 is latched in this position by a shoulder 80 on a lever 81, which engages an arm 77 on the lever, but at the end of the rotation of the shaft 50, when the cam roller slides down the flank 62b of the cam, the lever 81 is moved by the end of the link 72 to unlatching position. The lever 75 is then returned by a spring 84 and moves the shutterblade to the open position, in which it holds it until the pin 87 slides over the end of the lever, when the spring 88 closes the shutter. The camera is focused by means of a reflex finder having a pivoted mirror which is moved out of the path of the image beam, by a linkage system connected to a hinged cover, when the cover is closed over the finder.