Patent GB-654967-A (GB)
Title: Photographic apparatus for use in copying
IPC: G03B27/50
Filed: 1948-01-07
Abstract: 654,967. Photographic copying apparatus. DIEBOLD, Inc. Jan. 7, 1948, Nos. 541 and 542. Convention dates, Nov. 14, 1945, and Aug. 8, 1946. [Class 98 (i)] In copying apparatus of the kind in which the image of a stationary copy is projected by a lens on to a film moving in the focal plane of the lens, a movable light-deflecting member located in the optical axis of the lens is provided to transmit to the lens successive images of parts of the copy to form a complete image of the copy on the film, the light-deflecting member and the film being moved in timed relation. As shown in Fig. 2, the book 83 carried on a flat or curved support 82 is illuminated.by lamps 85, 86, and is scanned by a rotatable mirror (or equivalent reflector) in a cylindrical casing removably supported between the front and rear walls of the cabinet, and having an opening in the lower part thereof, of variable length, to admit light. The length of the light path is variable by means of mirrors 43, 44, 45, 46 in a telescopic housing 39, 41. The light beam is focused as a slit image, by a lens 34 with slit diaphragms 35, 36, on the surface of a photographic film movable over a drum 26. The cylindrical casing 52, Fig. 3, has a bracket supporting a synchronous electric motor 55, which drives, through a reduction gear 56, if required, the mirror support 57. A shaft 61 fast with the mirror support is journalled in a partition 60, and carries a disc 64 fixed thereto and rotatable arms 65, 66. The casing 57 is turned by hand until a catch 94 engages a notch in the disc 64, in which position the mirror scans the left-hand edge of the copy. The arm 65 is then set to the number on a scale corresponding to a number on a scale in line with the beginning of the part of the copy 83 to be photographed. Arm 66 is similarly set for the end of the part to be photographed, and the arms are clamped by a knob 67 threaded on shaft 61. In operation, a main switch is closed, supplying lamps 85, 86, a signal lamp, the motor 55, and a film-driving motor. The mirror scans the copy, throwing an image to the optical system; the slit 35, however, is closed by a magnetically-operated shutter blade. The film-driving motor drives the film through an electrically-operated clutch; which at this stage is disengaged. Operation of a push-button 90, Fig. 3, operates a relay which extinguishes the signal lamp, and makes ready a second relay circuit which is closed when the arm 65 operates a switch 70 on the housing 52. This relay engages the clutch in the film drive, opens the shutter, and lights another signal lamp. The film then moves during the scanning of the copy, the speeds of the two motors being such that the speed of the film equals the apparent speed of the image projected thereon. When the end of the part of the copy to be photographed is reached, the arm 66 opens a switch 71, interrupting both relay circuits and returning the circuits to their condition prior to depression of the pushbutton 90. The page is turned and the pushbutton 90 depressed to photograph the next page. Alternatively, a switch is operated to short-circuit the push-button 90, in which case a photograph is taken at each revolution of the mirror, the pages being turned by hand or by mechanical means in the non-photographing part of the cycle. In a modification, in which the apparatus can also be used to project an enlarged image from a film on to sensitized paper on the support 82, the film drum 26 is made transparent and contains a projection lamp. The modification also includes one of three alternative forms of scanning device, in which the mirror is driven through a clutch. (1) Where the clutch is similar to the filmdriving clutch, the driven shaft 135, Fig. 13, has a bearing 137 in the front plate and the mirror support, carrying a disc 143 with a pin 144, is loosely mounted thereon. A disc 146 rotatable on the bearing 137 carries a stop 145, against which pin 144 is urged by a spring 160. By turning a knob 151 fast with a gear-wheel 148 engaging the toothed edge of disc 146, the disc is turned until the mirror is in a position (determined by pin 144 and stop 145) to start scanning the desired portion of copy, and locked by a nut 152. On depressing the switch to start the process, the clutch is actuated and the mirror moves against the action of spring 160. Arms 153, 154 operate circuits controlling film movement &c. in a similar manner as arms 65, 66 above. When the portion of the copy has been photographed, the clutch is released and the mirror returns under action of spring 160. The switch initiating the film movement may be actuated directly by pin 144. (2) The clutch is mechanical and operated by a lever, which is moved by an adjustable starting arm to engage it, and by an adjustable stopping arm to disengage it. These arms also operate the filmdriving &c. switches. (3) The starting switch may operate, through an electromagnet, a clutch of the kind which is engaged for a single revolution only. Any of these scanning devices, but particularly the last, may have a housing with light-excluding flaps hinged at each side of the light admission aperture. They are adjustable to include any chosen part of the copy, and may be extensible so that their ends always rest on the copy. When the modified apparatus is used for projection from a moving film, the sensitized material is placed on the copy support 82. It may be stationary, in which case the operation is similar to the copying process, but the lamps 85, 86 are extinguished, and the projection lamp in drum 26 lights only when the image-bearing film is moving. When the singlerevolution clutch is used it may be operated by the operator's foot, electrically or mechanically. In an alternative mechanism for operating a magnetic clutch, the motor-driven shaft has two insulating discs adjustably clamped thereto. The discs have conducting strips extending partially along the periphery of each, which are in contact with each other. A stationary brush contacts each strip, and a clutch-actuating circuit is closed when both brushes contact a strip. The Specification as open to inspection under Sect. 91 comprises also apparatus in which the light-sensitive paper for receiving an enlarged image is not held stationary, but is moved at the same speed as the projected image. This subject-matter does not appear in the Specification as accepted.