Patent GB-830431-A (GB)
Title: Improvements in photographic type-composing machines
Inventor: CHEETHAM CLIFFORD
IPC: B41B21/36
Filed: 1957-05-29
Abstract: 830,431. Photographic type-composing. MINISTER OF AGRICULTURE, FISHERIES & FOOD. May 29, 1957, No. 17016/57. Addition to 824,105. Class 98(1) A photographic type-composing machine of the kind described in the parent Specification comprises a first part through which the control member is arranged to move the film during its forward movement and a second part through which the control member is arranged to move the film during its return movement, each part being movable only in a given direction to cause a proportional movement of the film, each part having a contact surface inclined to the said direction, the movement of the control member being applied to the contact surface of each part at an angle to the direction of movement of the part, and means for changing separately the inclination of each part whereby the distance the film is advanced during each of the forward and return movements of the control member may be changed separately. As shown in Fig. 1, a frame 1 of light metal carries a transparent plate 2 with a fount of characters formed thereon. The top edge of the frame above each character is cut down by an amount proportional to the set width of the character concerned. The right hand end of frame 1 is supported by a boom 12 having a wheel 13 running on a bearing surface 14 at right angles to the plane of frame 1. An arm 15 pivoted at 16, 17 is pivoted to the mid-point of boom 12. A similar arrangement (not shown) supports the other end of frame 1 and is connected by a spring 18 to boom 12, so that the frame is movable in its own plane to carry the characters through a photographing station. A desired character is located exactly in the photographing position by a pin 21 entering a corresponding hole in a line of holes 20. A solenoid 30 is then momentarily energized to rock an arm 31 to release a cam 32 mounted on a shaft 11 driven through a slipping clutch 33, so that the shaft may rotate once before the cam is re-engaged to hold the shaft stationary. A control member 7, fixed to a rod 35 engaging the high point of a cam 36 at the beginning of a revolution, descends until it engages the indented edge of the frame 1. A bar 8 pivoted at 56 follows the member 7 and presses down an intermediate lever 42 carrying wheels 43, 44 which force apart parts 45, 46 mounted on arms 47, 48 connected to an electromagnetic clutch lever mountings 49, 50, which are thus moved in opposite directions round the periphery of a control disc 9. The clutch levers are actuated alternately by coils 51, 52, energized through a distributer having a semi-circular conducting surface 55 coacting with contacts 53, 54, and driven through bevel gearing by shaft 11. One clutch is engaged while the control member 7 is ascending, and the other while it is descending, so that disc 9 is turned twice by equal amounts and in the same direction, so that the film, mounted on a drum 6 on the same shaft as disc 9, moves through a distance equal to the set width of the character in two equal stages. The spacing may be varied by altering the inclination of the parts 45, 46, which, as shown in Fig. 2, are formed as levers pivoted at 60, 61 and may be rotated by telephone-type dials 62, 63. They are held in adjusted position by pawls 64, 65 which are linked by rods 66, 67 to lever 42, and are released from their corresponding ratchet teeth after exposure of the film when the lever 42 rises. The parts 45 46 then return to their initial position under action of springs on the dials. The size of the character image projected on the film by a lens 5 is varied by altering the relationship between the character carrier 2, the lens 5 and the drum 6. Movement of drum 6 causes movement of the intermediate lever 42 to alter the inter-character spacing in proportion to the change in the size of the character image. The mechanism for locating the characters is shown in Fig. 4, where bolts 71, 72 with complementary bevelled ends are mounted on plates 74, 75 pivoted near their lower edges. Plate 74 is mounted in bracket 78 which is rocked slightly against a stop 81 by a spring 80. When the plates are rocked towards each other by rotating a link 76, the bolts enter a hole 75 in frame 1 with their bevelled ends in contact. As their movement continues their combined thickness increases (bracket 78 rocking away from stop 81) until they fill the hole.