Patent GB-190823684-A (GB)
Title: Improvements relating to Photographic Printing Apparatus.
Inventor: LAKE WILLIAM EDWARD
Filed: 1908-11-05
Granted: 1909-04-15
Abstract: 23,684. 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 F, Figs. 3 and 4, carrying a light-chamber A, a back-support or pressure device B, a frame K for holding the negative or positive plate E, and a frame I carrying the sensitized plate or stone. The lightchamber A, having electric illuminating-devices 93 and a transparent face-plate 94, is moved to and fro in-guides 90 by a .screw 95 working in the cross-piece 27 of the side frame G. To enable this to be done from the opposite side, a band-shaft 140 is journaled in the cross-piece 32 and is arranged to drive a bevel-wheel 149 engaging a wheel 150 on the threaded sleeve 97, in which the screw 95 works in this case. The upper and lower portions of the face-plate 94 are preferably covered by opaque curtains 116. The pressure device B is mounted in guides 130 in the side frame H and is adjusted by a screw 134 working in the crosspiece 32. The main pressure-plate 155 is provided with a supplemental pressure-plate 160 having a yielding facing 161. Pressure can be applied separately at different:parts of the plate 155 by shafts 156 carrying, cams or eccentrics 157 preferably acting on springs 158 and bolts 159. The plate E, Fig. 8, has bevelled edges secured under shaped bars 100, 101 which are secured to sleeves 103, 104 carried by screws 102 on the frame K ; the sleeves 103 can be raised or lowered on unthreaded portions of the screws, while the sleeves 104 are threaded and are moved by the screws 102 which are geared together by the shaft 105. The bar 101 is -braced by an adjustable bar 117, and the plate E is held against lateral displacement by arms 120. The frame K has slots 113 and is secured to the frame G by screws 112, which allow a partial rotation of the plate E for registering it on the face-plate of the light-chamber A, gear 114, 115 being provided for this purpose. The frame I has tongues 35, Fig. 3, working in side-posts 20 of the frame F and is adjusted vertically by screws 36 journaled in the-frame F and rotated by a shaft 40. The position of the frame I is ascertained by a pointer on the frame I and a pointer adjustably secured to a scale on the frame F. For carrying a sensitized plate, the frame I has top and bottom holding- means, Figs. 5 and 6. The former comprises a bar 47 having a dovetail tongue 48 sliding in a groove in the frame 45 and held by a plate 49 ; the bar 47 has a web 50 against which the plate C is clamped, a tightening wedge-plate 52 being provided. The latter comprises a bar 66 sliding in the frame 46 and carrying, integral or attached, a web 68 to which the plate C is secured, a wedge-plate 71 being used. The wedge-plates have lugs 24 working on screws 75 to slide the carrier transversely, a pointer 86 moving over a scale on the frame F having adjustable pointers. The screws 75, Fig. 11, are geared to bevel-wheels 83 having their hubs held in bearings 79 and engaging with shafts 77 rotated by a shaft 85, Fig. 4. The wedge plates have inclined faces, Fig. 3, and are moved under or away from the nuts 54 by levers attached to the frame-bars 45, 46. The lower holding-devices may be vertically movable by levers attached to the frame 46, for stretching the plate. A lithographic stone D, Fig. 11, may be mounted by attaching a channel-bar 165 to the bar 66 ; the stone rests on a dovetail plate 167 which works on rollers 168 in the chamber-bar 165. Uprights 169 and screws 170 keep the stone in position. 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.