Patent GB-670005-A (GB)
Title: Apparatus for photo-composing purposes
IPC: B41B15/04
Filed: 1948-12-09
Abstract: 670,005. Photographic type-composing apparatus. NAAMLOOZE VENNOOTSCHAP EX= PLOITATIE MAATSCHAPPIJ QUOD BONUM. Dec. 9, 1948 [May 13, 1948], No. 31878/48. Class 98 (i). The apparatus includes a photographic copying camera having its optical axis horizontal and means for simultaneously moving horizontally an objective carrier and an object holder relatively to a dark slide elevated such that correct focus is maintained as the magnification is changed and is characterized by means for intermittently moving the dark slide elevator vertically a distance which is proportional to the displace . ment of the objective carrier from a position in which the magnification is unity, said means comprising a detent conpled to the objective carrier and co-operating with an abutment on a rod which is axially movable and one part of which is formed as a rack, an adjustable stop on said rod co-operating with a fixed stop to control the axial movement of the rod in one direction while the detent and abutment control such movement in the opposite direction, a gear-wheel incorporating a freewheel driver mounted on a shaft at right angles to the rod and engaging said rack, a second gear. wheel on the shaft engaging a rack rigid with the dark slide elevator, and ratchet-means to prevent reverse rotation of said shaft. The apparatus shown in Fig. 3 includes a holder 3 for a line of type 1 to be copied, and an objective carrier 5 supporting a lamp 8 for illuminating the line of type 1 and connected by bellows 15 to a fixed upright 6 on which an elevator 10 carrying a dark slide 9 is guided for vertical movement. The objective carrier 5 is movable by a screwed spindle 7 on which the holder 3 is slidable and the carrier 5 and holder 3 are connected together and to the upright 6 by a; focusing mechanism, as described in Specification 24292/11. The screwed spindle 7 is geared at 18, 19, Fig. 4, to a shaft carrying an axially-adjustable detent which lies in the pathof an abutment 22 provided at one end of a sleeve threaded on to an axially movable rod 32. A rack 30 on this rod is engaged by a gear-wheel; 28 incorporating a free-wheel device 29 and mounted on a shaft 25. The latter carries another gear-wheel 26 engaged with a rack 24 on 'the dark slide elevator 10, and also a ratchet mechanism 27 for preventing reverse rotation of the shaft 25. The rod 32 has therein an adjustable stop 35 for co-operation with a fixed stop 36. For use, the objective carrier is first moved to the position in which the magnification obtained is unity and the rod 32 is thereafter moved to the left in Fig. 2 until abutment 22 engages detent 21. The stop 35 is then moved along the rod until its distance from the stop 36 is such that the allowed movement of rod 32 to the right in Fig. 4 is sufficient to move the elevator 10 through a distance equal to the height of the line of type 1 to be photographed. In order to photograph successive lines of type at the same magnification, it is thus only necessary to move rod 32 forward and backward after each exposure to effect the necessary movement of the elevator 10. When the objective carrier 5 is moved to vary the magnification, the position of the detent 21 and therefore the stroke of rod 32 are varied in proportion. If it is desired to move the elevator a distance independent of the magnification of the preceding line of type, abutment 22 is adjusted by rotating a pinion 34 meshing with a pinion 23 on the other end of the sleeve carrying the abutment. A shutter 11 for the dark slide is clipped to the upright 6 at 12 and light from the objective passes through a slit 16 in the upright. A mask 17 is provided for adjusting the width of the slit 16.