Patent GB-905456-A (GB)
Title: Improvements relating to photographic type composing machines
IPC: B41B27/00
Filed: 1958-10-01
Abstract: 905,456. Photographic type - composing apparatus. MERGENTHALER LINOTYPE CO. Oct. 1, 1958 [Nov. 14, 1957], No. 31308/58. Class 98 (1). A photographic type-composing machine includes, in combination, means for feeding through the machine a coded tape provided with a succession of code signals representative of a composed line; means for decoding the tape signals as the tape is fed through the machine; a font plate presenting an array of type characters varying in set widths on a unit basis; means for photographing characters one after another for composition in a line; a light-sensitive film on which the characters are recorded; means for producing a relative movement between the light-sensitive film and the photographic means for line composition; a unit measuring device for the line composing movement; means responsive to decoded character identification signals to control the selection of the type characters to be photographed; means respon. sive to decoded character width signals as well as to the unit measuring device for varying the time of photographic action for the successive characters being composed in accordance with set unit widths of the characters; and means responsive to decoded word space signals as well as to the unit measuring device for determining the extent of the line composing movement between words in accordance with the set unit width of the spaces; the aforesaid means for varying the time of photographic action for successive characters as well as the means for determining the extent of the line composing movement for interword spaces comprising a memory storage unit wherein the width value for each selected character or word space as it is decoded is temporarily stored and then cleared prior to the entry of the next selected character or word space, a counter unit actuated by the unit measuring device for counting each unit of relative movement between the photographic position and the film as the movement is measured by the unit measuring device, and a coincidence unit connected to and actuated by the memory storage unit and the counter unit to determine when there is coincidence between the count in the counter unit and the width value stored in the memory storage unit, the coincidence unit controlling thereby the photographic and interword space action of the machine. As shown, the machine is of the kind described in Specification 801,481 but differs in the form taken by the memory storage, counter, and coincidence units and in that provision is made for quad right and centring operations. Composition is effected on a stationary film by continuous along-the-line movement of a prism carriage and a grating formed by rows of transparent marks at intervals of one space unit chosen equal to <SP>1</SP>/ 18 th of an em of the chosen point size, there being rows for each of the point sizes, 5, 5¢, 6, 7, 8, 9) is secured to the carriage to move between a lamp and photo-cell arrangement so as to provide pulses measuring the carriage travel. The counter unit (Fig. 11) consists of bi-stable electronic multivibrators (flip-flops) arranged in cascade as a five-stage binary counter, of which only the first and last stages 202, 203 are shown, and the memory storage or memory unit (Fig. 11) consists of five separate stages each formed by bi-stable electronic multivibrators of which again only the first and last stages 182, 183 are shown. Each corresponding stage of the counter and memory storage units is connected to a stage of the coincidence unit, forming together a comparator 222, each such coincidence stage as 245, 246 comprising a parallel pair of triodes. In the zero state the right-hand tube of each pair of each unit is in the conducting state. When coincidence is achieved between the states of all the stages of the counter and memory storage units, triode 223 in the coincidence detector unit 219 (Fig. 12) is cut off and so causes triode 244 to conduct, indicating coincidence. Control tape and tape decoding.-The control tape 77 (Fig. 2) has feed-holes 78 and is provided with rows of perforations indicating character, space, and end-of-line instructions. A character row 80 comprises a character identification portion 81 and a character width portion 82 while a space row 83 includes a " function" signal perforation 88. Four kinds of " end-of-line " instructions are provided, viz. (1) justification, requiring an operation row 85 including perforations 87, 88 and a justification space width answer row 86 comprising a space width quotient portion 90 and a quotient remainder portion 91; (2) quad left, requiring only an operation row including perforations 87, 88; (3) quad right, requiring an operation row 93 including perforations 87, 88 and a quad right answer row 94 comprising a quad ems-tens (tens of ems) part 95, a quad ems-units part 96 and a quad space units part 97 together with a function perforation 87; and (4) centring, requiring an operation row 100 including perforations 87, 88 and a centring answer row 101 comprising a centring ens-tens part 102, a centring ens-units part 103 and a centring space units part 104. The space unit employed is 1/18 of an em of the chosen point size, the along-the-line movement being measured in these units. Decoding is effected in substantially the same manner as in Specification 801,481. Perforation 87 effects decoding of " end-of-line " signals at the scan head while perforation 88 effects " function " signal decoding at the read head. Tapeoperated finger levers at the scan head, one lever for each code perforation to the right in Fig. 2 of the left-hand feed-holes 78, short out the cathode resistors of triodes so that anode relays 1SD ... 13SD (Fig. 5, not shown) are energized, thereby storing " end-of-line " instructions on input circuits to triodes as 176, 177 in the space and character width memory input 171 (Figs. 9, 10) and on stepping switch JST (Fig. 6) for justification quotient and remainder, respectively, and on stepping switches QTST and QUST (Fig. 7) and input circuits to triodes as 176, 177 for quadding right or centring tens of ems or ens, units of ems or ens and space units respectively. Similar levers at the read head select the character to be recorded and set up the character widths on the memory input 171 as well as decoding spacing signals and " endof-line " signals. Initially the tape has to be disposed as described in Specification 801,481 with an " end-of-line " marking at each head after which the decoder heads ensure progression of the tape, and to ensure even for the shortest line, bridging of the decoder heads a blank length of tape sufficient for this is left between the leading end of line row and the first character row position. Before an " end-of-line " answer row can be decoded and the answer stored in the machine, a start photography button SP has to be manually operated to energize a self-holding relay controlling machine operation. Simultaneously with initiation of photographic composition of the line the scan head is actuated to bring the next " end-of-line " marking to the decoding position where it remains while the preceding line is composed, the " end-of-line " marking is decoded at the reading head and the carriage return and interline feeding of the film are effected. Thereafter with " end-of-line " markings at each head the cycle is continued. The timing of the stepping of the tape relative to prism carriage movement and photographing operations is described in Specification 801,481. Justification storage and justified line production.-With an " end-of-line " operation at the read head and contacts SP closed relay RELD is energized by a circuit through the device unit and the closed contacts in parallel with contacts ELG1, and a justification operation row 85 at the scan head causes energization of relays 3SD, 5SD, 7SD, thereby energizing justification relay JD and relay SELD. As a result of the closings of contacts SELD1 and RELD3, the driving coils of the stepping switches JST, QTST, QUST step the switches back until their brushes, such as JB1, QTB1, QUB1, are on the home contacts such as JC1-H, QTC1-H, QUC1-H. The driving coil circuits are then broken, arresting the movements of the brushes since simultaneously contacts JST1, QTST1, QUST1 close to energize relay ELG, so deenergizing relays RELD, SELD while relay JD remains energized, and contacts JST2, QTST2, QUST2 open. Thus relay JS (Fig. 8) is energized over closed contacts JD2, ELG7 and when the tape has fed forward one row to bring the answer row 86 to the scan head, the justification quotient perforations 90 energize one or more of relays 9SD ... 13SD which in turn energize the appropriate combination of binary stage relays BO ... BS (Fig. 8) so that the quotient is stored by appropriate switching of the inputs to the tubes in the memory input 171 such as tubes 174 and 176 representing one and sixteen, respectively, while the quotient remainder code 91 operating one or more relays 4SD ... 8SD allows switch driving coil JST energized via closed contacts JS3 to step the switch until the column number of the contacts on which the brushes rest is equal to the remainder in space units. A circuit is then completed via closed contacts JS2 over switch JST to short out the driving coil and energize relay JAS, so deenergizing relay ELG. If there is no quotient remainder, the switch JST steps into contact column 25 where it is arrested. Unless there is no quotient remainder, the " add one " relay AO is energized at the same time as the binary relays BO for distributing the remainder a unit at a time between the word spaces until it has been accounted for. When the tape is now stepped to bring a character row into the read head, switches operated by tape perforations in character selection code 81 of row 80 operate shutters to select the desired character on the font plate and via block 253 (Fig. 9) positively bias the chara