Patent GB-209070-A (GB)
Title: Photomechanical apparatus for transferring designs from flat to cylindrical surfaces
IPC: G03F7/24
Filed: 1923-12-21
Abstract: 209,070. Lithoprintex Corporation, (Assignees of Jones, H. C., and Darby, J.). Dec. 23, 1922, [Convention date]. Enlarging, copying, and reducing.-For the production of printing rollers, the design or transparency is directly copied by projection on to a sensitized roller the support of which is rotated in unison and in proportion to the linear movement of the design carrier, which is actuated through two co-operating members, such as a slide and slide block, one of said members being moved linearly in unison with the rotation of the roller support, and the other being connected to the design carrier to move said carrier. The apparatus described enables the ratio of enlargement to be adjusted so that during a complete traverse of the original the roller just completes one revolution. In a modification, the apparatus may be adapted for automatic focussing. In one form, the sensitized roller 6, Fig. 4, is adjustably mounted between lock nuts 19 on a spindle 18 mounted on pillow-blocks 14, 15 on the main frame 4 and rotated, through a worm 21, Fig. 1, and gear wheel 16, from a shaft 7 driven by a pulley 22. The blocks 14, 15 and the shaft 7 are adjustable horizontally to and fro so as to bring different sized rollers tangential to the focal plane of the lens 13. Stop apparatus is provided to allow the roller to make one complete revolution only at, a time, and consists of a wheel 8, having a pin 9 held and released by a control lever 10, and geared to a worm 35, on the power shaft 7 so that it moves at half the speed of the roller 6. When the wheel 8 has made half a revolution it is stopped by the pin 9 engaging an adjustable bracket 11 and stops the roller 6. Movement of the carrier 1 of the original in its vertical supporting guides 3 is simultaneously effected from the shaft 1 through worm 35, gear wheel 8, and shaft 8<1> provided with spur gear engaging racks 45, 45<1> on rods 43, 43<1> to move the rods to and fro. Differential apparatus for transforming the horizontal motion of the rods into vertical motion of the carrier 1 is connected to each rod and consists of a bar 50 slidably mounted on a guide 53 attached to the main frame, and secured to the end of the rod 43 by lock nuts 49 so that it can be adjusted with respect to the vertical guides 3 of the carrier 1. An inclined guide bar 55 is pivoted at one end 56 to the bar 50 and has its upper end adjustably locked in a curved slot 59 in an upright extension 60 of the bar 50 by a nut 62 having a handle 63. The slide guide attachment between the carrier 1 and the inclined bar 55 consists of a triangular plate 65 having rollers 66, 66<1>, 60<11> which engage the opposite sides of the bar 55. The plate 65 is pivoted to a slide 69, Fig. 5. locked to the carrier 1 during motion thereof. Movement of the rod 43 causes the plate 65 to move down along the inclined bar 55 causing the carrier 1 to descend. The vertical movement of the carrier, which is balanced in its guides 3 by counterweights 70, is varied by varying the inclination of the bar 55 which can be effected by locking the carrier 1 in position and moving the guide 69 vertically on the carrier 1 by means of a shaft 74 mounted thereon and rotated by a handle 73, gear wheels 75, 76, and a vertical screw 77 having thrust collars 78 on each side of its bearing on the carrier and engaging a threaded boss 79 on the slide 69. Adjustment of the design to its zero position is effected by locking the guides 69 in position by means of the nuts 62 and moving the design carrier with respect to the guides 69 by rotating the screw 77 by turning the handle 73. Adjustment scales 81, 82 are provided on the carrier 1 and slide 69. A variable light slot 80 in front of the carrier 1 is formed by two horizontal plates movable to and from each other by gearing operated by a handle 91. A similar light slot is formed at the focal plane of the lens 13, tangential to the roller 6, between two horizontal plates 92, 92<1>, Fig. 1, adjustable on vertical brackets 93, 93<1>. Means 31, 31<1>, Fig. 4, for trueing the roller 6 with respect to the focal plane of the lens are slidably mounted on a horizontal bar 95 which can be temporarily secured to the uprights 93, 93<1>. A small focussing ground glass may be slidably fitted to the bar 95 to examine the design image before the roller is adjusted in position. A bellows or light shields may be provided along the optical axis. In a modification, the plate 65 may be connected to the rod 43, and the inclined bar 55 connected to the slide 69 on the carrier 1. In a further modification, the support for the sensitized roller 6, the lens 13, and the frame for the carriage 1 are each mounted on supports slidable in guides longitudinally of the main frame so as to adapt the apparatus for automatic focussing, or for use with various lenses with manual focussing. Specification 12438/12 is referred to.