Patent GB-973313-A (GB)
Title: Improved method and apparatus for error correction of information recorded in a combined printing and recording machine
Inventor: ASHBY CHARLES GEORGE
IPC: B41J3/50
Filed: 1961-12-07
Abstract: 973,313. Typewriters. IMPERIAL TOBACCO CO. (OF GREAT BRITAIN & IRELAND) Ltd. Dec. 6, 1962 [Dec. 7, 1961], No. 43817/61. Heading B6F. An apparatus for the correction of an error made in a line of printed characters on a sheet of paper selected characters of which are simultaneously perforated or magnetically recorded on a tape, comprises means for setting tabs in correspondence with the selected characters, power-operated means for returning the sheet and tape to a correction position for correction of an error, power operated means for cancelling of the printed and perforated characters extending from the correction position to the end of said line, means operable consequent on correction of the error for re-recording the cancelled characters and means for resetting the tabs. Type-lever actions; printing and perforating machines; keys actions.-In a typewriter 1, (Fig. 4, not shown) associated electrically with a punch 3, having six punches for code perforations, an order sheet 5 is fed into the carriage 6 and the sheet is divided into a printing zone comprising a column 7 (Fig. 1, not shown) and a punching zone comprising columns G8 ... G8-4, P8 . . . P8-4 and 8 ... 8-4, whereby whilst the carriage is in the position of column 7 the type keys operate to type only, whereas when the carriage enters the punching zone, selected type keys for use in this zone operate to type on the sheet 5 and perforate a tape 51 (Fig. 3, not shown). The commencement of the punch zone on the sheet 5 is indicated by a colon on depression of a key marked B/E referred to as " block end " the depression resulting in simultaneous perforation of the tape in an appropriate code for recognition in a computer. The beginning of subsequent columns is indicated on the sheet and tape by an oblique stroke and coded perforation on depression of a key marked N/E (number end). When a complete line has been typed and recorded on the code perforated tape a carriage return key 24 is depressed, which resets a switch 100, Fig. 12, breaking the supply to the selected keys operable in the punch zone and also energizes a solenoid 31, Fig. 6, to reset tabs 14 by a bar 32 rubbing against the lower ends of the tabs to raise them to their rest position 13. A back spacing key 12, Fig. 12, is depressed on error detection which electrically spaces the carriage back step by step until a first unset tab 13 is reached. If the error has not then been reached the back spacing key is depressed again until the error is reached. The error and the remainder of the line is deleted on the sheet and overperforated on the tape by a deletion key 107, whose type face carries a symbol " W." Keys construction; electromagnetic operation.- As each key is depressed it rocks its lever 72, Fig. 5, which through a drag link 74 pivots a push link 75, said link rocks a bell crank 77, which in turn through a rod 79 raises the type lever 80. Sixteen of the selected keys (in Fig. 2, not shown) for operating in the punching zone are provided with switches 9, which close the circuits to the corresponding encoding matrix 101, Fig. 12, in the punch so that the correct code for each key is perforated. Three of the sixteen keys may be operated automatically i.e. the B/E, N/E and deletion (W) keys, by external energization of solenoids 82, with which the keys are provided. The automatic initiation of the punch zone is effected by a tooth 49, Fig. 11, secured at the rear of tab bar 11, so that as it moves with the carriage it closes a micro-switch 50, which energizes the solenoid 82 of the B/E key. The beginning of each column is also preferably initiated automatically and the N/E key is operated by teeth 45 on a bar 44 attached to the rear of the tab bar 11, the spacing of the teeth corresponding to the spacing of the columns, the teeth 45 closing a micro-switch 46, which energizes the solenoid 82. Tabulation mechanism.-Depression of one of the sixteen selected keys in the punch zone closes the switch 9, Fig. 2, which through the encoding matrix 101, operates a solenoid 26 so that in addition to typing and perforating it set also a tab from its unset position 13, Fig. 6, to a set position 14. The solenoid via an associated linkage pulls on a rod 20 attached to an arm 18 pivotally attached at 19, which imparts downward movement to a strip 15, whose hooked end 16 sets the tabs. The tabs are reset by a solenoid 31, actuated by the carriage return key 24, and which raises a bar 32 chamfered at 33, the chamfer causing the set tabs back to their rest position on carriage return. Back-spacing mechanism; error detection and correction.-If an error has been detected it is necessary to back-space both the type sheet and perforated tape to where the error occurred which is effected by depression of the backspacing key 12, Fig. 12, which sets a switch 103 to permit electric pulses emanating from a carriage back-space solenoid 104 through delay D1, switches 38 and 88 to back-space the carriage step by step until the first set tab 14, Fig. 11, is reached whereupon a light beam from a source 35, which is no longer obturated by the unset tabs 13, shines on the window 37 of a photo-electric cell 34 setting the switches 38 and 88. The pulses emanating from the backspacing solenoid 104 pass also to the punch back-space solenoid 52 to back-space the perforated tape 51, by rocking an arm 54, Fig. 8, provided with a rocker 58 having a tooth 59, whereby an end 202 on the arm 54 strikes the upper end of the tape forward feed pawl 62 to pivot it clear of the teeth of ratchet wheel 65 while further movement of the arm 54 brings the tooth 59 into engagement with a tooth of star wheel 71 to turn the wheel in the reverse direction one tooth space the non-return lever 67 which was forced out of engagement snapping into the next tooth to prevent overdrive of the axle 66 on which the tape is mounted. On return motion of the arm 54 the rocker 58 pivots against its spring 61 to clear the teeth of the star wheel and the lower end 202 releases the pawl 62. The back-spacing movement of the carriage and punched tape continues until a further unset tab 13 is reached whereupon the obturated light beam resets the switch 38 again and a pulse passing through contacts 41 and 99 resets switches 88 and 103 through a delay D2. The back-spacing key 12 is depressed again if the error has not yet been reached. On reaching the error the deletion key 107 is depressed operates to cancel the error and the remainder of the line by setting a switch 1104, which through a line K closes the circuit to the solenoid 82 operating the deletion key so that " W " symbols are printed on the sheet and all six punches of punch solenoids 1102 operate to cancel the code on the tape. Also the first movement of the carriage will make the light beam shine on the window 37, as the tabs are in a set condition, so that the switch 38-1 moves into its set condition to a switch 106 through a line M, contacts 40-1 and 95. On reaching the end of the line the light will once more be obturated by a beam of light and the switch 38-1 reset and the reset pulse along the line L, will pass along lines M, P and switch 106 to set a switch 86 which acts to cut off pulses to the deletion key and initiates pulses to the carriage back space solenoid 104, through contact 97, so that the carriage is spaced back to the point of beginning of cancellation. The switch 86 set also a switch 87, which via contact 98 sets a switch 105, so that when the carriage is spaced back to the beginning the unset tab thereat resets the switch 38-1, whereby a final pulse will pass through contact 41-1, lines P, U and switch 105 to reset switches 1104, 105, 86, 106 and 87 to stop the carriage. The error may now be corrected by retyping the line on the sheet above the cancelled line and reperforating the tape, the corrected code perforations following immediately the overperforated codes (Fig. 3, not shown).