Patent GB-832908-A (GB)
Title: Improvements in or relating to means for converting from one information code to another
IPC: H03M5/00
Filed: 1956-06-26
Abstract: 832,908. Code telegraphy. COMMERCIAL CONTROLS CORPORATION. June 26, 1956 [Nov. 15, 1955], No. 19780/56. Class 40 (3). In an arrangement for converting from one code form to another, in which the information recorded on a medium in which one form is read and translated into the second form and recorded, and in which the two code forms have portions which are common and portions which: are different and distinctive of the two code forms, code conversion means is arranged to be responsive to the occurrence of the distinctve code form portion of the first code form to effect the recording thereof in the second medium in the form of its distinctive code-form portion. In the embodiment described for the conversion from a six-unit code to a five-unit code, five units occur identically in the two codes and the nature of the sixth unit which is indicative of the case of the 5-unit character causes the insertion of the appropriate 5-unit code for letter shift or figure shift respectively in the converted 5-unit code. Similarly, in converting a 5-unit code to a 6-unit code, the occurrence of the letter shift or figure shift signal controls the nature of the sixth element added to the original five unit signals, until the occurrence of the other shift signal. As described, signals recorded in a perforated tape are read and applied to a circuit which controls the punching magnetsfive or six-to perforate a tape according to the converted code. Driving arrangements, Figs. 5, 6.-The shaft 88 or 223 of the punching or reading unit respectively is connected by a flexible coupling 38 to a shaft 33 driven through a clutch and start-stop mechanism from a pulley 32 coupled by a belt to the driving motor. A cam 42 connected by a collar 80 to the shaft 33 carries one or more keys 84 engaging in circumferential slots of a clutch housing 77 connected by a spring 79 to an extension 81 of the collar 80. For the punching unit, the shaft is held in normal position by a projection 76 engaged, when a magnet 40 is de-energized, by the end of an arm 74, secured by a block 75 to the armature 70, when the latter is in its released position. The energization of the magnet 40 withdraws the stop arm 74, and when the projection on the collar is re-engaged by the release armature 70 to arrest the shaft 33, the force of the impact is taken up by compression of the spring 79 permitted by the movement of the key in the circumferential slot, and the shaft 33 is finally held in its rest position by a spring biased keeper latch 48 engaging a projection 47 on the collar adjustably secured to the shaft 33. The armature 70 is positively restored to its normal position by an arm 44 of a lever rocked by the engagement of a roller 43 with a cam 42 secured to the sleeve extension of the collar 80. For the reading unit, which can be arrested after half a revolution, the sleeve is provided with two diametrically opposed projections 76, and the collar 47 has two projections operating in conjunction with the latching member 48. Punching and perforating arrangement, Figs. 10, 11, 12.-The punch pins CP1 ... CP6, and CP for perforating the feed holes, are operated by levers 75 pivoted on a rod 96 carried by frame 97 comprising side members 98 pivoted on a shaft 100 and provided with rollers 110, 111 engaging cams 108, 109 in the shaft 88 coupled at 38 to a shaft 33 which rotates through one revolution for each punching operation. The rear ends of the levers 95 cooperate with latch members 114 controlled by the armatures 122 of the magnets 90 selectively energized according to the code combination to be punched. The upper portions of the latches 114 normally engage notches in the armatures 122 and the energization of a magnet 90 releases the latch to move forward to retain the rear end of the associated lever 95 against the shaft 100 so that the upward movement of the frame and the shaft 96 positively move the punch pin CP through the tape. If the rear end of a lever 95 is not latched, the upward movement of the frame 97 by the cams 108 raises the rear end of the lever from the shaft 100. The cams 109 engaging the rollers 111 positively move the frame downwards to withdraw the punch pins. A lever 126 rocked by a cam 125 rocks a lever 126 carrying a locking bail 131 which engages above or below the pointed ends 132 of the arms 133 of the latches 114 which are locked in their selectively set positions. A bail 150 carried by a lever 151 rocked by a roller 152 on a cam 134 engages the arms 133 to move the latches 114 anticlockwise so that they are latched in their normal positions by the armatures 122 restored to their normal positions by a restoring bail 156 carried by a lever 154 having a bar 153 engaged by the movement to the left of any of the latches 114 by the restoring bail 150 if they have not been restored by their springs 123. The sprocketwheel effecting the feed of the tape is stepped by a ratchet-wheel 143 on the shaft 144 and engaged by a spring-biased pawl 138 on a lever 135 carrying a roller 136 engaged by a cam 134 on the shaft 88. The positive feed rotation of the ratchet 143 is limited by a plate 138a engaging the pawl 138, and a detent roller 148 on a spring-biased lever 146 prevents reverse movement of the ratchet 143. The punching arrangement is disabled when the tape breaks, is exhausted, or is subjected to excessive tension, and additionally when a curved guide member normally holding the tape against the feed sprocket is rocked to a position to allow fresh tape to be inserted. These arrangements, which are described in connection with Fig. 8 (not shown), comprise a pivoted lever carrying the tape guide member connected by a lost motion linkage to a further pivoted lever carrying a bar engaging the upper surface of the tape after it has been perforated, and linked to a lever which opens control contacts if the tape supply is exhausted or broken. A further pivoted lever carrying a roller is rocked if the tape tension becomes excessive and through a bail extension rocks the lever to open the contacts in the circuit controlling the operation of the punching mechanism. Tape-sensing and signal transmitting arrangements, Figs. 14, 16, 17. Levers 205 controlled by pins 227 arranged to be operated in accordance with the perforations in a tape fed by a pin wheel 234 each control two contact assemblies 200 in which the central springs 204 are held in the positions shown, but which are biased to move inwards when the associated lever member 205 is liberated by the detection of a hole in the tape by its corresponding sensing pin 227. The sensing pins 227 are carried by interposer arms 225 biased upwardly by light springs 230 and carrying shoulders 226 arranged opposite the upper ends 207 of the levers 205. A bail member 219 overlies the arms 225 and is raised during the reading cycle by an arm 220 carrying a roller 221 engaged by a cam 222. The upper ends 207 of the levers 205 are normally held away from the shoulders 226 by bail members 211 carried by levers 213 having at their upper ends two pairs of rollers 214- normally held apart by studs 215 carried on frame members 216 carrying the member 219. For the sensing operation the bails 211, 219 move respectively inwardly and upwardly, and those pins which encounter perforations and move upwardly remove the shoulders from their blocking position relative to the associated upper ends 207 of the levers 205 which move inwardly under the action of the central springs 204 to close the opposite contacts of the contact pairs 200. The downward movement of the bail frame 216 causes the bail member 219 to restore the pins 227 which found perforations and also to reinsert the studs 215 between the rollers 214 to open the arms 213 and move the bails 211 outwardly to return the levers 207 to their normal position. The pin wheel 234 for feeding the perforated tape is stepped by a ratchet 236 engaged by a spring-biased pawl 237 carried on a lever 239 secured to a yoke 243 rocked by a cam 242 on the shaft 223, the ratchet being retained by a jockey roller 250. The tape is held against the sprocket 234 by a guide member 252 carried on a pivoted lever 251 having a cam extension 256 engaging a pin 257 on a lever 258 to open contacts RTC when the guide member 252 is rocked away from the sprocket 234 to insert fresh tape. The absence of tape is detected by a spring-biased pivoted arm 260 having a lateral extension 265 normally located beneath the tape and a downwardly extending arm 263 provided with a stud 264 engaged by the lever 251 so that the movement of the guide 252 away from the tape rocks the lever 260 downwardly. If the tape supply fails the arm 260 rotates in a clockwise direction and the arm 263 engages the stud 257 on the arm 258 to open the contacts RTC. Excessive tension in the tape is effective through a tape guide member to rock a lever 268 clockwise so that an extension 270 opens a normally closed switch 271 to arrest the action of the tape reader. The movement of the lever 268 is limited by the engagement of a slotted arm 274 with the upper part of a fixed bracket 272. Circuit arrangement for conversion from a 6- unit to a 5-unit code, Figs. 20, 21.-The sensed perforations of the 6-unit tape control reading contacts RC1 ... RC6 and the punching of a tape according to the 5-unit code is effected by magnets PM1 ... PM5 as described in connection with Figs. 10, 11, 12, under control of a punch clutch magnet PCM. Power is supplied to the apparatus by operating switches S1, S1<1> and D.C. operating potential is derived from a rectifier R and is applied over conductors 300, 303 to conductors 304, 308 completing the circuit of the reader clutch magnet RCM when the read switch S2 is moved to the " on " position and the tape controlled contacts PTC of the punching apparatus, Fig. 21, and RTC, RTTC of the reading unit, Fig. 20, are in their unoperated positions. The shaft of the reader unit is rot