Patent GB-190823690-A (GB)
Title: Improvements relating to Photographic Printing Apparatus.
Inventor: LAKE WILLIAM EDWARD
Filed: 1908-11-05
Granted: 1909-04-15
Abstract: 23,690. Lake, W. E., [Huebner, W. C., and Bleistein, G.]. Nov. 5. Printing.-An apparatus for producing prints on the sensitized surfaces of metallic or other plates, or on lithographic stones, in predetermined. locations, comprises a frame A, Figs. 3 and 5, holding the sensitized plate B or stone, and carrying a frame D in which are mounted a light-chamber E, and a back-support or pressure device F. The sensitized plate B, preferably of zinc or aluminium, is held by top and bottom holding-bars 23, 33, Fig. 12. The bar 25 is secured to cross-pieces 24 of the end frame 20, and the bar 33 to posts 42 bolted to the frame. The plate is clamped against the angle-iron 23 by a clamping-plate which is held by bolts 27 tightened by a wedge-plate 29. A lever 31 linked at 32 to the wedge-plate 29 operates the latter. The bottom holding-means comprises a similar bar 33, bolts 35, wedge-plate 36, and lever 38. To obliterate all bends and irregularities in its surface, the plate is stretched between the top and bottom bars 23, 33, by a lever 40 having a pin working in a slot 44 in the bar. 33 and secured to the post 42 by a bolt 41, the bar 33 being secured to the post 42 by bolts 45 working in slotted boles A lithographic stone C may be mounted in the frame A by securing yokes 152 to bottom bars 32 of the frame. The yokes carry a beam 151, which is adjustable by screws 153 and which is grooved to take a dovetailed tongue of the carriage 150. The beam also carries brackets 154 having screws 155 to clamp the stone. The top rail 21 of the frame A, Figs. 3 and 5, has tongues 54 engaging in slots in the top member of the carriage D, which has shoes 55 sliding in V-shaped grooves in the bottom rail 22 of the frame. Lugs 62, 63 engage with screws 60, 61; geared together by a shaft 64 to traverse the carriage, the position of which is indicated by adjustable and fixed pointers 69, 70 and a scale 68. Fig. 2. The side frame 50 of the carriage guides the frame 9, which is elevated by screws 84, geared together by bevel-wheels 88 keyed on the shaft 86, adjustable and fixed pointers 92, 93 and a scale 91 beiug provided to indicate the position of the frame G. The printing- plate 73 is bevelled and is secured to a frame H by bars 100, 101 secured to sleeves 103, 104. The sleeves 103 are secured on unthreaded parts and the sleeves 104 on threaded parts of shafts 102 geared together. The frame H has slots 113 and is secured to the frame G by screws in the slots, which allow a partial rotation of the plate for registering it on the face-plate of the light-chamber E, gear 114,115 being provided for this purpose. The frame G has brackets 79 carrying guides 78 for shoes attached to the light-chamber, which can be moved in by screws 82 working in the cross-piece 83. The light-cbamber has a hand-hole, closed by a cover 76, and a face-plate 72, Figs. 3 and 5, a diffusing-plate 74 being preferably provided. The upper and lower edge portions of the face-plate 72 are covered by opaque curtains 116. The side frame 51 of the carriage D guides the frame I, which is elevated by screws 124 geared together by bevel-wheels keyed on the shaft 126 preferably geared to the shaft 86 by a shaft 127 so that the light-chamber and the back support may be adjusted simultaneously. The pressure device F is supported by shoes running in guides 122 in brackets 123 attached to the frame 1, and is moved in by screws 130 working in a cross-piece 131. The main pressure-plate 35 carries a supplemental pressureplate 136, loosely attached by pins 137, so that it can be replaced by a larger or smaller one. The plate 136 has a yielding facing 133 of felt or the like. The main plate 135 is attached to the frame I by two bolts 140 fitted loosely into an upright bar 141, so that it can tilt to a certain extent. Pressure can be applied separately at different parts of the plate 135 by shafts 142 carrying handles 144 and cams or eccentrics 143 acting on bolts 146 and rubber sleeves or springs 145. The shafts 142 are removably mounted in the frame I as by being journaled in removable blocks 148. To provide several plates &c. with prints for different colours, the plates &c. are successively exposed, the correct position being readily produced by the aid of the scales and pointers.