Patent GB-706312-A (GB)
Title: Improvements in and relating to machines for producing type faced impressions in or for printing
IPC: B41B7/04
Filed: 1949-03-12
Abstract: 706,312. Typewriters; printing surfaces. CLOWES & SONS, Ltd., W., and CROUCHER, H. G. March 13, 1950 [March 12, 1949] No. 6848/49. Classes 100 (2) and 100 (4). [Also in Group VIII] Type-case machines.-A machine for typewriting, cutting stencils, or stamping, the products of which may be finished printed sheets, or surfaces for use as printing surfaces or in preparing printing plates, comprises a casing carrying type or die members individually displaceable therein so that any one character face may be advanced beyond the remainder, means for temporarily effecting such advance of a selected member, a plane table for supporting a surface to be printed or punched, means for effecting relative movements between the table and the casing in directions (a) to cause an impression on, or punching of, the receiving surface from the advanced type or die, and (b) to determine the position of the impression on the receiving surface, and means for controlling movements (b) to form spaced lines of characters on the receiving surface. The advanced type member may be inked before, and cleaned after, each impression by rollers on a swinging arm ; or it may print through an ink (or leaf or pigment) ribbon ; for gold blocking its face end may be heated by a gas flame. To facilitate the correction of errors &c. punches (see Group VIII), incorporated in the machine may form perforations at the ends of each line printed. In making planographic printing plates the machine may print with ink on a prepared metal plate or, for offset printing, on a rubber transfer sheet ; for relief printing surfaces the machine may emboss a thin plate, may print with a marking ink on a light-sensitive sheet which is then exposed, developed and used to make a process block, or may form a stereotype mould by impressing on wet or dry flong, lead, wax, celluloid or thermoplastic resins. The machine may also be used for making metal stencils (by supporting a thin metal sheet on a resilient surface on the table), for chemical printing, or for charging paper &c. in character areas by means of electrically charged dies. As described the casting machine of a known single-type composing apparatus, pneumatically controlled by a perforated strip prepared on a keyboard mechanism, is modified by removal of its die case and matrices, centring pin, mould, molten metal supply means, and type collecting mechanism, and by addition of the parts indicated below. Types and type-selecting and projecting mechanism.-The individual types or dies may be type-faced members 8, Fig. 6, each having a reduced central shank 11 surrounded by a retraction spring 19 which bears on a washer 18 straddling two support bars 14 ; permanent- or electromagnetic means may replace the springs 19. The lower parts 10 of the members 8 may be formed as holders for conventional printers' type : they may have a spring side wall with a positioning block engaging the nick in the type side, or according to Fig. 62 may be of anglesection 485, 486 ; a spring plate 487, acting through an exchangeable packing piece 493 retained by one or more projections 488, presses the type 492 against the flange 486, and a spring rod 490 presses it against the flange 485. A die case 9, Figs. 6 and 9. containing 225 dies 8 in 15 lines, and having slots covered by external plates 16 in two of its sides to take the ends of the bars 14, a perforated cover 22 allowing passage of the projector head 21, and flanges 39 engaging a cross-slide 40, is slidable in the latter width-wise, Fig. 9, by means of its arm 23, while the slide 40 is slidable at right angles thereto on the edges of a fixed plate 30; the existing pinblock and tong mechanisms of the casting machine may be connected to the arm 23 and slide 40 for this purpose, or other mechanism such as a keyboard may be used to move the die case for type-selection. The die case 9 and slide 40 are locked by toothed plungers 54, 55 pressed onto racks 24, 56 by springs 59 as three parallel arms 45 of a cam-actuated bell-crank lever descend, the centre arm releasing the die projector 20 so that its spring 44 forces it down until adjustable nuts 52 engage a fixed stop 53 ; in a modification the stop 53 is replaced by a wedge device connected to the slide 40 so that the stop point of the projector 20, and therefore the amount that the selected die is projected, varies over the lines of dies 8. The projected die is clamped by a device 31, Figs. 9 and 11, comprising jaws 61, 62 closed, 61 directly and 6 via a push-rod 67 and lever 68, by a bell-crani lever 65 connected to a cross-bar spanning th arms 45 ; in a modification, e.g. for gold blocking" the device 31 is replaced by a fram carrying a gas ring located between two horizontal heat-resisting plates each with an aperture through which the die 8 is projectec (According to the Provisional Specification th rear ends of the members 8 have conical recesse and the end of the projector 20 is conical ; th bars 14 and springs 19 are in central slots within the members 8 ; a metal guide plate with ex changeable aperture plates replaces the devic 31 ; and for gold blocking &c. long die member 8 have cross holes just behind their faces into which a blue gas jet is directed, a stream o cooling air being applied above the heated zone; Platen table.-As shown in Figs. 15, 16 and 43 the paper or other impression material 370 i held down on a plate 369 by spring strip clamp 371 hinged at one end 372 and secured by thumb screws 373 at the other; the plate 369, exchange able for another of different width to suit the paper width, rests in recesses in the tops of bar 358 having studs 368 at their ends adjustable in slots 367 in runners 366 fixed to a plate 365 supported on a box casting 110 which, for the positioning movements (b) above, is slidable along glide bars 77 secured to tie bars 78 slidable in horizontal slots in a rectangular frame 79 ; for the impression movement (a) above, the latter is vertically slidable in the main frame 25. That part of the plate 369 beneath the die projector 20 is supported by an anvil 375 fixed to two rails 359 secured to blocks 354 on the frame 79. In a modification all the parts above the plate 365 are replaced by an inverted box-shaped structure containing a steam, gas or electric heater, e.g. controlled by a thermostat. The table may be resiliently supported to allow for die depth variations. The impression movement (a) is imparted to the frame 79 by mechanisms at both sides, each comprising a cam F (Fig. 14), follower lever 86, lever 88 coupled thereto by a retractable tapered bolt 89, link 90, spring-loaded bell-crank lever 91, adjustable link 92, and a cam bar 82 slidable between rollers 81 on the frame 79 and adjustable rollers 83 on the main frame 25. Both bolts 89 may be withdrawn (i) by pulling a handle on the end of a rod 96 carrying forks 95, and (ii) by movement of the existing trip rod of the casting machine to " half " or " full " position (see Justifying-mechanism and Carriage-returning mechanism below), which moves forks 309 to cause arms 312 carrying the bolts to slide along the shaft 87. (According to the Provisional Specification rollers beneath the frame 79 rest on antifriction rollers or blocks resting in turn on cams on a rotatable shaft ; the intermediate rollers may be laterally displaced to interrupt the impression movements). The positioning movement (b) along the lines of print are powered by two single-acting oppositely arranged cylinders 112, 113 (Fig. 15), one supplied with compressed air, and the other connected to atmosphere, through a cam-controlled valve which momentarily reverses the connecttions for table-return at line ends ; beyond the cam-controlled valve a 3-position manuallycontrolled valve also reverses the connections in its two end positions to provide for use of the machine in offset and direct printing, and in its mid position connects both cylinders to atmosphere so that the table may be moved by hand. The positioning movements (b) in line depth are caused by weights 80 (Fig. 14) connected by cables to the tie bars 78, matter being reproduced from bottom to top of the page ; the table is manually returned to the bottom of a new page. Both the above movements (b) are controlled by escapement mechanisms comprising camactuated wedge clamps, see (1) below, by which the box casting 110, or the tie bars 78, are clamped to stationary parts (the glide bars 77 or the frame 79) and to longitudinally sliding bars 107, or 174, Figs. 15 and 16 ; the clamps are released alternately, and during their release from the stationary parts the sliding movement of the bars 107, see (2) below, or 174, see (3) below, is limited to correspond to the required letter or line spacing. (According to the Provisional Specification the table positioning movements (b) are powered by pneumatically- or camactuated racks which engage pawls to unlock the wedge clamps ; a further rack-and-pawl arrangement re-locks the wedge clamps). (1) For letter spacing the low parts of cams A, B (Fig. 15) alternately release levers 142, 143 each connected by a collapsible link 145, 146 to a spring-loaded lever 144 ; the high part of the cam A or B forces its lever 144, through a rod 147 and spring 148, to actuate a lever 149 engaging one or two fork members 150 on crossbars fixed to longitudinally slidable bars 151 whose cam-slots 152 are engaged by rollers 153 on vertically movable bars 154 engaging the ends of plates 156 having longitudinal slots engaged by rollers 135a each on a wedge 135 (Fig. 22) which forces apart two lateral wedges 136 arranged between blocks 137 (on the casting 110) and the glide bars 77 or the longitudinally sliding spacing bars 107 ; on retraction of the wedge 135, bell-crank levers 138 free the wedges 136. Another pair of cams, one of which is shown at D (Fig. 14), operate the wedge clamps for line spacing. The lever 143 (Fig. 15) lie