GB182887A - Mechanism for the photographic reproduction of type or other characters - Google Patents

Abstract

182,887. Broadbent, W. April 7, 1921. Enlarging, copying, and reducing; type composing.-In apparatus for photographically composing type comprising a number of negatives or positives bearing the characters which may be projected in any order, by means of separate optical systems on to a movable sensitive surface at a common focus, the negatives are provided with individual shutters which may be actuated manually, or pneumatically from a perforated strip. Means are also provided for spacing the letters and justifying the lines. The negatives or positives are carried in a frame 1, Fig. 1, between which and a source of light 3 are shutters 2 for each character. The images are projected by separate lenses and prisms 4, 5 to a common focus 6 on a movable sensitive band 7 mounted on reels in a compartment 8. The supporting-frames for the lenses, shutters, and negatives may be of partspherical form. The shutters may be operated from a keyboard and the band 7 moved at each operation as in a typewriter; or they may be operated pneumatically from a perforated strip 9, Fig. 3, passing over a tracker bar 10 having apertures connected with the shutters. A separate perforation is made at the end of each line to advance the sensitive band. Two apertures for each letter are provided, one to release a control 2, Fig. 2, for a selected row of shutters and the other to select the particular release 4 for the desired letter A in this row. The perforations are so spaced as to allow for the varying widths of the characters and, as an alternative, for the justification of the lines also. The justification spaces may be governed by two sets of perforations at the completion of the punching of each line, the insertion of these spaces throughout the line being governed by a common space perforation. The strip for this method may be made by a keyboard strip perforating machine such as described in Specification 17199/08, [Class 100, Printing, Letterpress &c.]. The justification perforations are two in number. One is used to move pneumatically a series of cams 11, Fig. 6, on a hollow shaft to an extreme pesition, and the other to position a stop controlling the spring return movement to bring a selected cam opposite a lever 12. This lever controls the position of the continuously rotating friction disc 13. The spacing cam is thus selected for each line and is rotated each time a space perforation on the band is presented, through the action of a clutch on the cam driving- shaft which is put into gear pneumatically. The disc 13 is thereby displaced to give the required speed for the particular spacing to the disc 14 which is coupled with the drive of the perforation strip 9, or, alternatively, with the sensitive film moving mechanism.