Patent GB-763463-A (GB)
Title: Improvements in or relating to apparatus for producing justified copy
Inventor: BLODGETT EDWIN ORSON
IPC: B41J19/64
Filed: 1953-12-16
Abstract: 763,463. Typewriters &c. COMMERCIAL CONTROLS CORPORATION. Dec. 16, 1953, No. 35028/53. Classes 100(3) and 100(4) A machine for producing justified copy comprises two, typewriters basically similar to that described in Specification 750,454 one of which (A) types a trial line, controls a tape punch 15, Fig. 1b, to simultaneously perforate a code in a record tape, and operate a justification computing means which controls the punch to perforate a justification code in the trailing end of a line of characters codes, and the other, (B), has a double tape reader 16 arranged so that the justification code is read by one reader JCR before the character codes reach the other reader PCR so enabling word spaces to be controlled to produce a justified line. An interlock between the readers is effective to render inoperative the justification reader JCR while a character code is being sensed in the character code reader PCR. The justification code comprises the holes 7 and 6, Fig. 73, together with various combinations of the 1-5 holes. This code, through the operation of various combinations of relays, automatically operates the variable escapement mechanism. Normally, word-spacing consists of two units of space, but upon justification word-spacing may consist of one to five units of space. The units of space necessary to effect correct expansion or contraction of a line are spread over the first eight word spaces in equal amounts provided no fractional units are involved but generally the space is spread over the first eight word spaces in two stages, firstly a word space of 2-5 units which is followed by a reduced word space of 1-4 units respectively as shown in the chart, Fig. 50. All word spaces after the eighth are 2 units. To effect justification and to ensure that there is sufficient distance in the tape between the first character code of a line and the justification code to enable the latter to be sensed before the former, a letter-space counter is provided which prevents justification in lines comprising less than thirty characters. Towards the end of a trial line a signal light above the keyboard comes on to indicate a letter-space zone in which the trial line may be ended so that the justifying typewriter is able to justify that line. The justification computing mechanism which determines the code to be punched in the tape at the perforator 15 comprises a code bar 693, Figs. 42, 43, attached to the carriage frame 692 of the trial line typewriter. The code bar 693 comprises five notched sections S1-S5 each having nine vertically spaced fields at levels corresponding to zero and eight stepped positions corresponding to word spaces. The frame 692 also carries a notched cam 690 controlling a seeker 688, Fig. 43, which closes a contact for the keyboard-light. When the trial line is completed, five seekers 638, Fig. 43, which have been stepped vertically at each word space by a justifying stepping magnet JSM, are permitted to engage the notched sections S1-S5 by the pull of springs 701 since a retaining bail 641 is operated in response to a carriage return actuation. According to whether the five seekers find a recess or a raised portion of a section S1-S5 so contacts JC1-JC5 are closed controlling the justification code punched in the tape. The punching is effected automatically in response to a carriage-return action, which in addition, punches a No. 7, interlock code between the two tape readers, and the carriage return code itself. If an error has been made in typing a line, delete key is depressed whereupon electromagnets in the translating mechanism, described in above-mentioned Specification, are made inoperative until a succeeding line of character codes is presented to the tape reader. Fixed word spaces of one and three units which have their own code may be reproduced unaltered in the justified copy by the provision of special keys in the trial line typewriter, and, if required, a non-justify key on the second typewriter cuts out the justifying mechanism so the trial copy is reproduced unjustified.