Patent GB-768981-A (GB)
Title: Photographic type-composing
IPC: B41B17/06
Filed: 1955-05-05
Abstract: 768,981. Photographic type-composing. KWEI, C. S. May 5. 1955 [Nov. 23, 1954]. No, 13044/55. Class 98(1) In photographic type-composing apparatus comprising a drum bearing on one part of its surface a negative with arcuate rows of characters to be photographed, and on another part of its surface a table of characters corresponding to the first characters arranged in similar rows. the drum being rotatable and movable axially, a light source is disposed one side of the drum surface to project an image of a negative carrier on to an exposure station, and a stationery index member is so arranged that it indicates on the table of characters the character corresponding to the negative carrier in position for exposure. As shown in Figs. 1 and 5, the drum 16 consists of a curved transparent surface 16a supported by a central ring 29 with spokes 30 connecting it to a central hub 31, and rings 27, 28 at the end of the cylinder. The lower part of the drum surface is ruled into squares 34 in which rows of characters are arranged. Similar characters, in transparent negative form, are carried on the upper part of the drum surface. The hub 31 is fixed to a sleeve 32 slidable on a column 25 uprightly mounted on the base 15 of the apparatus. Member 25 also carries an arm 24 supporting a housing 22 for a lamp 23, which is thus supported inside the drum opposite a camera 18. Preferably, the characters on the lower part of the drum are displaced through 90 degrees with respect to the axis of the drum as compared with the negative carriers on the other part of the drum. An index consisting of a square 48 is marked on an arcuate transparent strip 46 carried by upright supports close to the surface of the drum. When a character appears in the square 48, which may be viewed with the aid of a lens 48a, the corresponding character in the negative part of the drum is in position for exposure. Exposure may be effected by a pneumatic bulb 21 connected to the camera. As shown in Fig. 7, the weight of the drum is supported by a counterweight 40. A bracket 38, supported by uprights 37, carries pulleys 39. Counterweight 40 is connected to the outer race of a ball race 42, in turn connected to the sleeve 32. by a cable 41 passing over the pulleys 39. An upright strip 44, extending to just below the index 48, is formed with holes 44a spaced apart at the distance between the rows of characters. The bottom ring 27 of the drum has holes 27a spaced at the spacing between adjacent characters in a row. When a character is correctly positioned for projection, a pin 45 (see Fig. 10) is inserted through one of the holes 44a and also through one of the holes 27a. A wire hook 49 is shaped to embrace both the ring 27 and the upright 44 and is fitted with rollers 50 whereby it moves easily on the ring and the upright. This wire indicates the hole 44a just above it as being that in which the pin 45 is to be inserted. As shown in Fig. 12, the insertion of the pin may, if desired, operate a safety device which ensures that the character cannot be exposed unless it is properly positioned. An upright 52 carries insulated contacts 53 connected by wires 55 in the circuit of a motor 59. A spring blade 56 is mounted in front of the upright 52, and carries a bracket 56a on which an insulated strip 57 is mounted. When the pin 45 is inserted through the holes, it presses back the spring strip 56 so that contacts 53 are bridged by the strip 57. This completes the circuit to the motor 59, which operates a compressor which in turn operates the camera 18' pneumatically. Operation may be effected by means of a switch 61 in the circuit on motor 59. which is not effective unless the contacts 53 have been bridged. On retraction of pin 45, the blade 56 moves back, its movement being limited by a hook 52a mounted on the upright 62.