Patent GB-906113-A (GB)
Title: Type setting system and apparatus
IPC: B41B21/36
Filed: 1958-09-12
Abstract: 906,113. Photographic type-composing apparatus. AMERICAN TYPE FOUNDERS CO. Inc. Sept. 12, 1958, No. 8007/58. Class 98(1). Photographic type-composing apparatus comprises in combination a supporting frame; a rotatable character disc upon which is carried at least one set of master characters arranged arcuately on said disc and concentrically thereof from which selections are made for effecting composition; means for reproducing successive individual characters from said disc at a given point in the apparatus; and means for presenting selected characters on said disc at said point, the last-mentioned means comprising driving means for continually urging the disc to rotate about its axis in one direction only, means acting on said disc to arrest it at the next ensuing positioning of a given character at said point of reproduction, said means comprising at least one stop abutment on the disc displaced radially from its axis and one of a plurality of stop elements selectively inserted into the path of said abutment; and a carriage for intermittent movement of a sensitized sheet past the point of reproduction to space the recorded characters. The Specification defines photography as meaning any process in which an electromagnetic wave produces in a suitably prepared medium a visible image or a latent image which may be made manifest by suitably treating the medium, while the term sensitized sheet is stated to mean any sheet or tape as of film or paper adapted to receive such an image and record it. The invention is applied to a photographic type-setter unit B which is a modification for photographic recording of the proportional spacing automatic typewriter justified copy reproducer of Specification 763,463, wherein a punched tape prepared in an electric typewriter which also produces a trial copy is used to operate the reproducer by automatic operation of the keyboard mechanism, the tape bearing justification information as well as character and interword identifications. Essentially the modification consists in replacing the paper support roller on the reproducer by a photographic film carriage F and replacing the type basket and bars and ribbon by a rotatable master character disc D arrested with the required character in position at a fixed location relative to the keyboard 10B for optical projection on to the film under control of the appropriate keyboard lever mechanism and providing a lamp and a shutter S to effect a controlled exposure once a circuit is completed through the disc and the arresting mechanism, whereafter the reproducer typewriter carriage escapement is operated under the control of magnets such as LE1 (Fig. 4) to effect along-the-line spacing, cams I, II, III on the shutter shaft being provided to time correctly the cycle of exposure and escapement operation. As described in Specification 763,463, but not shown in the present Specification, the justifying interword spaces are introduced when the space bar is operated, closing a contact WSC and setting the appropriate escapement magnets by circuits through relays JR1 to JR5 which store the justification information for the line. The punched tape is fed into a print reader 16 comprising a justification reader portion 16J and a print reader portion 16P arranged so that the justification instructions for the line are read and stored in the relays JR1 to JR5 before the character and width information is read to operate a code selector 13 for printing. Preferably, the trial copy recorder includes both a tape punching and a tape reading head, which latter effects keyboard operation and simultaneously punching of a second tape whereby a corrected tape may be produced from an original tape by stopping this tape when an error is reached, manually keyboarding the correct matter, and advancing the original tape by hand until the erroneous matter has been passed and then recommencing automatic tape operation. Matter may be produced in different point sizes by the use of alphabets in different sizes on the same or different master character discs or by variable optical magnification by adjustment of the projection lens 220, the appropriate character spacing being derived by exchangeable gearing between the escapement driven typewriter stub carriage 425 and the film carriage F. Alternatively, the appropriate film feed for different point sizes may be obtained by arranging that during the character code print reading cycle the escapement mechanism is actuated more than once. In this way the film carriage could be arranged to have a 4-point unit movement and 8-, 12-, or 16-point movements could be provided by double, triple or quadruple escapement operation. Style as well as case changes may be obtained without change of character disc by including a secondary font on the disc, images of which are projected on to the film when a font or " mixer " shift code punched on the tape in the trial copy recorder on operation of the ribbon or " colour " shift key is read, the selection of the font as well as selection of upper or lower case characters on the disc being effected by adjustable prisms housed at E in the light path. Provision is made for lighting a signal lamp 770 when the secondary font is in use. If the secondary font is of a point size which is a multiple or submultiple of that of the primary font, the required escapement movement may be provided by multiple escapement operation brought into operation by the mixer shift code. If the character disc bears fonts with point sizes in non-integral multiple relation, e.g. 8- and 12- point, multiple escapement operation may be used for both fonts with an escapement unit which is the H.C.F. of the sizes, e.g. by using a 4-point escapement unit with double and triple escapement respectively. Master character disc.-Each disc D comprises a transparent plastic plate covering with an opaque masking material to provide transparent characters on a dark ground arranged in three identical sectors each bearing the same four alphabets disposed in concentric arcs which consist of radial rows of upper and lower case symbols operated by the same key arranged in a primary font, e.g. Roman, and also in a secondary font, e.g. of a different style such as bold type. More than two fonts of symbols may be provided if appropriate shift codes and mechanisms are provided. Each disc is centrally apertured so as to be exchangeably mounted on a hub 140 on a hollow driven shaft 128 between the hub and a clamping member 145 engaged by the key end 150 of a rod 130 within the shaft and urged inwardly by a spring 137 engaging a collar 132 slidable on the shaft and pinned to the rod 130, the pin 131 being located in a key-way 133 in the shaft. Driving buttons 115 on the disc are thus urged by the clamping member 145 into driven engagement with a peripheral depression 142 on the hub, thus continually urging the disc to rotate clockwise, the member 145 acting as a slipping friction clutch plate. A conducting ring 320 on the disc engaged by a brush 330 is extended at 321 to carry pins 325 which engage the disc arresting means-the key-operated H -shaped blades 390- to complete a circuit controlling the exposure movement of the shutter S. Optical system.-Light from a universallymounted lamp 225 (Fig. 21) passing through a condenser 230 adjustable to form an image of the lamp filament on the projection lens 220 illuminates that portion of the disc D lying in the projection gate formed by the vertical slot in the mask M and the character images projected via prisms 270, 271 in the housing E by the lens 220 are masked by the exposure gate 212 so that only one character is formed on the film in the magazine extending across the exposure gate from supply cassette 516 to takeup cassette 525. Character selection.-Instead of type bars being connected to the keyboard mechanism, each link 34 is connected by a rod 35a to a T- shaped lever 350 pivoted on a bowed wire 352 secured in the body frame 50a and slidable in a slot 376 in the upper part of a comb-like member 372. For each T-lever there is a corresponding H-shaped blade 390 located in a slot 382 in an inverted comb-like plate 370, a curved strip 380 fastened over the tips of the comb retaining the H-blades against the action of compression springs 400. As a key lever is depressed the corresponding T-lever is pivoted anticlockwise about the wire 352 and raises the H-blade so that the nose 397 slides past the catch ledge 417 on the resiliently mounted latch plate 415 and engages the inclined surface 418 of the plate which is thereby displaced rearwardly sufficiently for the ledge 417 to be withdrawn from a blade previously in the latched position so that this falls to the position shown, and as the T-lever arm 355 falls back the nose 397 slides down the surface 418 and latches on the ledge 417. In this position an extension 393 on the front limb of the H-blade is positioned in the path of a pin 325 on the master character disc to arrest this, as it rotates clockwise, with thee appropriate radial character row in the projection gate defined by the vertical slot 240 in the mask M. The chosen face of the character row is projected on to the film through the exposure gate 212 of a height of one line only by the positioning of the two right-angled prisms 270, 271 rotatable about axes parallel to their vertices by levers 282, 305 having limbs movable between stops and controlled by rotary solenoids 290, 308 energized by change font or " mixer " shift and case shift tape signals respectively, the prism system performing the functions provided in a typewriter by raising the type basket. Film magazine and film feeding.-The supply cassette 516 comprises end caps screwed on to the threaded ends of a rod 540 on which the film is wound and making light-tight joints with the ends of the cylindrical cover of the cassette formed with velvet-lined lips from which the film pa