Patent GB-905458-A (GB)
Title: A machine for producing a coded tape representative of type characters
IPC: G06F40/189
Filed: 1959-12-15
Abstract: 905,458. Strip-perforating machines; justifying type. MERGENTHALER LINOTYPE CO. Dec. 15, 1959 [Jan. 8, 1959], No. 42578/59. Drawings to Specification. Class 100 (3). A machine for producing a coded tape representative of type characters includes a keyboard, a character identification code mechanism acting in response to key actuation for producing character identification signals, an electronic line length indicator apparatus, means for setting the line length indicator apparatus to accord with a selected value of line length, and electronic means for actuating the line length indicator apparatus in response to operation of a character key adapted to subtract the set width of the character represented by the key from the preset line length and thereby indicate the line remainder. The line-length indicator comprises four cold cathode tubes each containing ten cathodes shaped in the form of the numerals 0-9, the tubes indicating tens of ems, ems, tens of units, and units, there being 18 units to an em. The line length is preset by three knobs, one of which controls both units tubes, and dials associated with the knobs also indicate the line-length through windows. The cathode tubes for tens of ems, ems, and units are controlled by magnetron beam switching tubes, while the tens of units tube, which only requires the numerals 0 and 1, is controlled by a bi-stable multivibrator. The keyboard forms part of a modified standard electric typewriter, and there are also provided two auxiliary keyboards, for function keys such as quadding, centring and justification, and for font control keys. On depression of a character key or space key, a character identification signal is passed to the perforator, and also a character width signal, as described in Specification 822,995. Furthermore, a number of pulses is fed into a counter (111) equal to the complement, with respect to the counter capacity, of the counter capacity in units; and thereafter an oscillator is actuated to generate pulses and pass them to the counter until the latter is filled, when an output pulse therefrom shuts off the oscillator, the pulses from which also pass to the magnetrons and multivibrator so as to deduct from the line length indicated the width of the character or space keyed. When the line remainder thus indicated by the tubes is reduced to 3 ems, an audio and/or visual signal is given that the line is justifiable. When the space key is depressed, a pulse is also delivered to a 5-stage binary space counter (181). On depressing the justification key, the counter 111 is shortcircuited, and pulses from the oscillator pass, until the line remainder becomes zero, to a further counter (191). When the readings of the counters 191, 181 correspond, a pulse is passed to a further counter (210), and the counter 191 is reset, so that the reading in the counter 210 at the end of the line is the justification quotient, the counter 210 being provided with an initial reading of 4 units, which is a normal space width. The reading in the counter 191 is the quotient remainder. When the remainder indicated is zero, the oscillator is shut off by an inhibitor triode. For each state which is in its counting or " 1 " state in the binary counters 210, 191, a pulse is transmitted by depression of the " end-of-line " key to a thyratron tube controlling a perforator solenoid, to record the quotient and quotient remainder on the tape. The counters 191, 210 are then re-set. The magnetrons are also reset by momentarily cutting off these voltages. For quadding right, the oscillator pulses are directed to the magnetron controlling the ems counter, for more rapid action, until the remainder is less than 2 ems, and the action then continues as for justification. For centring, each stage of the counter 191 is connected to the perforator circuit for the next lower counter stage. Specifications 754,648, 801,481 and 905,456 also are referred to.