Patent GB-563331-A (GB)
Title: Improvements in or relating to photo-mechanical typographical composing machines
IPC: B41B17/06
Filed: 1943-04-16
Abstract: 563,331. Photographic type-composing machines. ELLIOTT, R. C., DEWHURST, M. R., BOOTH J. B. S., and MONOTYPE CORPORATION, Ltd. April 16, 1943, No. 6123. [Class 98 (i)] In a type-composing machine of the kind wherein single characters or symbols are selectively and successively projected through a lens on to a light-sensitive surface to form on it composed and justified lines, the photographed impression being subsequently transferred by known means to the plate or cylinder of a lithographic or other press, the lens and the support for the sensitive material are both fixed and a reflector in the optical path between the lens and the sensitive surface is given successive linear movements which determine the positions of the sucessive images in a line. In the machine shown, the movements of which are pneumatically governed under the control of a perforated record strip, a master plate C carrying translucent characters is movable to bring any selected character into the field of an objective mounted in a tube B which projects an image on to sensitive sheet material D. A reflector A, comprising two reflecting surfaces A<1>, A<2> perpendicular to one another and at 45 degrees to the focal plane causes two right-angle diversions in the optical path x, y, z between the lens and the sheet D, and is carried by a frame A<3> slidable in a guiding frame A<4> in a direction parallel to the sheet D, so that movement of the reflector traverses the image across the sheet D without altering the length of the optical path. After each exposure, the reflector is moved to the right by an oscillatable gripper E which engages a draw-bar A<5> attached to the frame A<4>, the extent of the movement being determined by the setting of wedge members in an adjustable stop F, which are positioned, under the control of signals derived from the record strip, in accordance with the width of the character or inter-word or other space recorded. On completion of a line, signals from the record cause the operation of means which return the reflector to its starting position, feed the sheet D for the reception of the next line, and set two of the wedges of the stop F for justification of this next line. The record-strip is delivered to the machine in the reverse direction from that in which it was made, so that the justification perforations, which are made in it at the end of a line, precede this line in the composing machine, and the line is composed backwards. The cycle of movements involved in recording a character or space is derived from linkage systems operated by levers actuated by pairs of cams on two cam-shafts Y, Z, one revolution of which corresponds to one cycle. The operations above referred to occurring on the completion of a line occupy five blank cycles, and are effected from a shaft E36 which makes one revolution in this period. The master plate C, carrying translucent characters on an opaque background and opaque sections corresponding to fixed-length spaces is carried by a frame C<1> mounted in slides so that it may be moved horizontally in mutually-perpendicular directions. The desired character is selected by determining the extent of these two movements by the raising of one gauge pin in each of two sets C<3>, C<4>, under the control of perforations in the record. Jaws C<5>, C<6> are then moved up to the raised pin C<3> by levers C<7>, C<8>, abutments on the jaws engaging a head on a draw-rod C<21> connected to the frame C<1> by way of a cross-head, thereby moving the rod and frame to a position determined by the raised pin C<3>. A similar mechanism operates in conjunction with the pins C<4> to position the master plate in the perpendicular direction. The plate is locked in the adjusted position by crossed locking bars C<44>, C<45> which are raised to cause tapered ribs on them to engage between pairs of teeth C<49> formed on the underside of the frame C<1>. A vertically-movable upper part B<1> of the lens tube, previously held in a lowered position, is then pressed up by a spring to engage the master plate and surround the selected character. At the same time a lever B<11> is rocked and operates the shutter trigger B<8> to make the exposure. In order to vary the size of the characters, the lens tube B is vertically adjustable by a rack and pinion and is provided with a bellows extension B<16>, and the reflector A is also adjustable vertically by a rack and pinion operated wedge member A<6>. After the exposure the re-setting of the plate C for the next character is initiated and the reflector A is advanced by the gripper E mounted on a rock-shaft E<2> and having a head E<4> containing a sliding wedge which locks it to, and releases it from, the draw-bar A<5> during the operative and return strokes respectively. The amount of the advance is determined in accordance with the width of the character by the setting, as described below, of the stop F, which is engaged by a nose E<53> on the head E<4>. A clamp E<21> is operated to lock the draw-bar after each advance. On the completion of a.line of composition, the reflector A is returned to its initial position. For this purpose a sleeve E<35> carrying cams E<34>, E<38> is clutched for a single revolution to the shaft E<36> by the withdrawal, under the control of a perforation in the record, of a latch E<44> which normally retains a pawl E<45> from engaging a ratchet E<46>. The cam E<34> rocks a bell-crank lever E<32> which returns the draw-rod A<5>. During this movement the clamp E<21> and the wedge in the gripper head E<4> are rendered inoperative by a lever E<39> rocked by the cam E<38>, which operates a stopblock E<28> preventing movement of the clamp and rocks through a link E<41> a lever E<29> to lock a lever E<11> which operates the wedge. During the return movement of the reflector the film is fed to receive the next line of matter by means operated by a sprocket-chain drive D<35> from the rotating sleeve E<35>. The stop F which determines the movements of the reflector A in accordance with the widths of the characters and the interword spaces comprises a main wedge F<1> which is engaged by the nose E<53> on the head E<4>, and the setting of which alone determines the character spacing, two justification wedges F<2>, F<3> which are used together with the wedge F<1> to determine the widths of the interword spaces, and two transfer wedges F<4>, F<5> which come into operation respectively when characters or interword spaces are being recorded. The three wedges F<1>, F<2>, F<3> are set by means of jaws F<6>, F' which move up to positions determined by the raising of one of a set of gauge pins F<9>, which they engage, the jaws also engaging raised projections F<10>, F<27>, F<29> on bars F<11>, F<26>, F<28> extending from the wedges, which are thereby adjusted according to the position of the raised gauge pin. Owing to the record strip being reversed, the justification perforations in it are operative at the beginning of each line, and result in the setting of the wedge F<2> in the first cycle and the wedge F<3> in the second. At these times the bars F<26>, F<28>, which are hinged to the wedges F<2>, F<3> are raised by bell-crank levers F<34> so that the projections F<27>, F<29> on them are engaged by the jaws F<6>, F'. The bars F<26>, F<28> are then lowered, so that during the recording of the characters of a line only the wedge F<1> is adjusted. During character recording, the transfer wedge F<4> is reciprocated at each cycle of the machine and comes into operative position each time the main wedge F<1> is positioned, in which position it extends between a stationary abutment F<60> and the wedge F<1>, so that the setting of the wedge F<1> alone determines the movement of the reflector. When an interword space is recorded, the wedge F<4> is retained in inoperative position, and the wedge F<5> moves to operative position, in which it extends between the wedge F<2> and the wedge F<1>. The interword spaces are therefore expanded by an amount determined by the, setting of the justification wedges F<2>, F<3>. The wedges F<1>, F<2>, F3 are held by pins, one of which, F<35>, is shown in Fig. 1, which engage racks on them and are raised during the adjustment periods. The film-holder is shown in Figs. 6 and 7. The film passes from a delivery spool D<2>, between a presser bar D' and roller D<30>, beneath a stationary bar D <5>, between a presser roller D<6> and arcuate plate D', and to the takeup spool D<3>. The film is fed by rotation of the spool D<3>, the end of which carries a pin which engages a radial slot D<48> in the face of a ratchet wheel D<12> driven by a pawl D<14> mounted on a toothed quadrant D<15> which engages a rack on a plunger D". This plunger is moved against a spring D<18> by a lever D<20> connected to it by a lost-motion link D<21> and rocked by a cam D<19>, and returns under the action of the spring, during which return movement the pawl D<14> drives the ratchet wheel D<12> to feed the film. During the first movement the pivoted arcuate plate D' is rocked by the film passing over it until an arm D<25> extending from it engages a cam stop D<26>, so preventing further movement of the film. The amount of the feed may be adjusted to vary the line spacing by rotating the cam. The presser bar D4 and roller D<6> are carried by arms mounted on rock-shafts, the former being raised during feeding of the film and the latter subsequently to allow the quadrant D' to return under gravity to its initial position. The machine may be adapted for use with a film mounted on a plate, driven by a rack and pinion for line spacing, or with strip film on which the lines are composed end to end.