Patent GB-1065670-A (GB)
Title: Automatic photographic copying machine
IPC: G03B27/12
Filed: 1964-06-03
Abstract: 1,065,670. Contact printing apparatus. ADDRESSOGRAPH-MULTIGRAPH CORPORATION, CHARLES BRUNNING DIVISION. June 3, 1964 [June 28, 1963 (2)], No. 22978/64. Heading G2A. An original sheet and a copy sheet are conveyed in contact between an endless belt 160 and a transparent drum 48 having an internal light source 50. Means responsive to the presence of the original on the cylinder or drum control the automatic feeding of copy sheets to the apparatus. The original is fed from an upper assembly 54, and the copy sheets form a lower assembly 52. The two come together in a guiding channel 142, and are carried round the drum where the exposure is made, after which they are separated. The copy sheet moves upward, held against the belt 160 by vacuum means, past a roller 182 into a developing section 58. The belt 160 actually consists of a number of separate belts closely spaced together, and a partial vacuum is created in a chamber 174 behind them, so that the exposed copy sheet is held against and carried by the belts. A rake assembly comprises a series of wire loops 242 secured at one end to a shaft 244. The shaft can be turned so that the other ends of the loops can be protruded between the belts, or retracted therefrom Fig. 12 (not shown). When so protruding, the passageway up to the developing section 58 is shut off, as for instance when only a single copy is required. In this case, a resilient deflector blade 218 is lowered until it bears against the drum, so that the original and copy sheet are deflected to pass up through a passageway 234, between rollers 236, 238, and are discharged from the apparatus on to a receiving tray 70. The exposed copy sheet is then fed manually into the developer section 58. When more than one copy of the original is required, blade 218 is retracted out of contact with the drum, and the wire loops 242 retracted behind the belts; this is the position shown in Fig. 6. The original is retained on the drum while successive copies are made, these being carried one after the other by belts 160 up into the developing section, whence they are eventually discharged on to an external tray. The original sheet is supported on a carrier Fig. 2 (not shown) which has strips of magnetic material along each side edge and a further strip along the leading edge, so that it can be maintained in contact with drum 48 by magnetic means inside the drum. These comprise two sets of two permanent magnets 186 each. Each pair of magnets is disposed between two polepieces 188, and the two pairs are placed one at each end of the drum axis, so that they co-operate with the magnetic strips along the side edges of the original carrier. Thus the original is kept permanently in contact with the drum as it rotates, until such time as it is picked off by lowering the deflector blade 218 into contact with the drum. By mounting the magnets on a threaded screw rod which can be turned by a handle from outside the machine Fig. 15 (not shown), they can be moved axially closer together or farther apart, to suit original sheets of different widths. When the machine is initially switched on, feed wheels 82, engaging frictionally against the top copy sheet 28, carry it forward until its leading edge, guided upwards by a plate 112, trips the arm 114 of a switch 116. This stops wheels 82, so that sheet 28 is fed no further, and remains in this position until the original is fed in from table 144. This is advanced until its leading edge trips the arm of a switch 152, which causes a roller 122 to move against a continuously rotating roller 118. Since the leading edge of copy sheet 28 was lying between these two rollers, this is now gripped between them and its feed movement resumed. When the original trips switch 152, it has just passed between rollers 154, 128, the latter being continuously driven. Thus it is carried forward through a guide path to meet the copy sheet coming up through a second guide path, the two paths coming together at 142, where original and copy sheet are brought into superimposition before being carried on to the drum 48. When repeat copies are to be made from the same original, as the original is carried round again on the drum after the copy sheet has been detached and conveyed up towards the developer section, it passes under a roller 200 normally bearing against the drum. This actuates a switch assembly 196 which sets in operation the mechanism for advancing a further copy sheet. Fig. 17 (not shown) is a diagram of an electrical circuit for controlling the various operations. By means of a control panel on the front of the apparatus Fig. 1 (not shown) it may be set for single copies, or for a sequence of a predetermined number of copies. If the supply of copy paper becomes depleted, the feed mechanism is automatically interrupted, and an indicator lamp lights up.