Patent GB-917445-A (GB)
Title: Data processing and display system
IPC: G06F3/12
Filed: 1961-07-14
Abstract: 917,445. Data display systems. GENERAL PRECISION Inc. July 14, 1961 [Sept. 22, 1960], No. 25567/61. Class 40 (1). [Also in Group XVI] A data processing and display system comprises means for selecting one of a number of holder units, each of which includes a recording medium, and for recording information, for example by printing. In the embodiment described, the holders are stacked to form a bay, Fig. 1 (not shown), a bay being indicated at 212 in Fig. 5. Each holder in the bay is identified by markings, as described later, and information which is to be printed in a holder is always preceded by signals indicative of those markings. Information from computer 200 will be accompanied by such signals, the information being routed to the relevant holder and there printed. The computer output for each block of informais seven groups of signals. These pass to distributer 202 which feeds the groups to the seven registers 203-209. The first signal group identifies the holder to which the information message is directed, and is fed to a comparator 211. The second input to the comparator is derived by scanning the holder markings. The markings on each holder comprise metal strips 35, Fig. 3, which co-operate with a matrix of magnetic cores situated beneath the holders, when mounted in the bay. The section 23 of the holder can slide in portion 25 and includes an impression surface (shown in Fig. 2) on which characters are to be printed. The core matrix, Fig. 4, comprises seven cores in a row, there being one row for each holder in the bay. The physical arrangement is such that the three ends of each core lie close to the bottom of a holder and hence in close association with any metal marking strips thereon. Each core is wound so that a pulse applied to the centre winding produces no output on the winding on the outer limbs unless the magnetic circuit is unbalanced by the presence of a marking strip, as at 35. Thus, if the rows are sequentially pulsed, pulses will appear on the output terminals of the seven columns according to whether or not a marking strip is present. Referring again to Fig. 5, multivibrator 215 feeds counter 216 which indicates the count by five unit binary code on its five output leads. This output feeds a switching matrix 217 which produces sequential pulses to scan each of the holder markings in turn. Thus the second input to the comparator comprises a number of groups of signals, sequentially presented. When similarity is detected the comparator opens gate 218 which therefore passes the count indicated by counter 216. The count is processed in a selector 220 which comprises twentyfour solenoids 318, Fig. 8, one solenoid only being energized by the count signal, whereby the relevant holder is selected. When energized, the solenoid raises catch 319 which engages with the associated holder. The pulse from comparator 211 sets unit 214 which operates motor switch 221a to actuate motor 221. This causes movement one way or the other of the bank of solenoids and consequent movement of the impression surface of one holder into the printing position. The second signal group indicates in which field printing is to be effected. Each impression surface of a holder has five fields for printing, each field allowing four rows and four columns of characters to be printed. Movement of the solenoids 318, Fig. 8, by one character width causes cam 321 to revolve once and tb actuate a microswitch 322. This constitutes detector 223, Fig. 5, the pulses being counted at 222. When the field signal from register 204 and the count of the pulses from 223 agree unit 224 pulses, the impression surface then being in the correct position. This pulse sets unit 225 wbich applies brake 225a to the motor. This brake is also shown at 325, 326, 329, Fig. 8. The third signal group indicates on which of the four rows in the field printing is to be effected. Referring now to the character positioning mechanism, Fig. 12, the characters 8 are carried on an endless belt driven by motor 226. Ink ribbon 14 is driven slowly by motor 445. Each character must be capable of resting in four positions, according to the row to be printed, this being accomplished by a braking system comprising four notched discs 412-415. The notches of adjacent discs are staggered as indicated, and are engaged by bars 441 when the corresponding solenoid 433-436 is energized. In Fig. 5, the output from row register 205 feeds selector 228. This gives a signal which actuates one of the four brakes, shown in detail in Fig. 12 and at 230a in Fig. 5, when unit 230 is set. This is described below. The fourth to seventh signal groups indicate which characters are to be printed. Since the characters are moved to the impression surface it is necessary to bias the belt 7 from its zero position (which it assumes after printing each group of four characters) to position the zero position character over the impression surface. To switch 233, therefore, there is supplied the count from counter 216, indicating the selected holder. This is applied to set counter 234, and indicates the amount the belt has to be moved to bias the zero position of the belt over the correct holder. Until counter 234 has counted down to zero, unit 235 gives no output, unit 230 is reset, and brake 230a disengaged. The printing mechanism now moves the belt, and the pulses from one of the microswitches 427-430 associated with cams 420-423, Fig. 12, i.e. from detector 231, Fig. 5, are passed to counter 234. When the counter reaches zero, unit 235 pulses, unit 230 is set, and the appropriate one of the brakes 230a is applied. Unit 237b is also set and causes clutch 238 to be engaged. The belt now has its zero position, which is a blank character, biased to be over the relevant holder. Motor 239 causes printing of this blank, a cam and microswitch arrangement, i.e. detector 240, giving a pulse at each printing operation which disengages clutch 238, thereby to stop multiple printing of the same character. This pulse is also applied to step counter 222 on by one and to unit 225. This unit therefore releases brake 225a, allowing motor 221 to step the impression surface on by one character, at which position detector 224 will again pulse, set units 237a and 225, and apply brake 225a. The pulse from detector 240 also passes to switch 233 and causes the signal in register 206 to be transferred to counter 234. This signal indicates how much the belt has to be moved from its biased zero position before the first character can be printed. When the belt has been moved far enough, printing occurs, and the signal in register 207 is passed to counter 234. This latter signal indicates how much and in what direction the belt has to be moved from its previous printing position to place the correct character in the printing position, the impression surface having been stepped on by one character width meanwhile. This operation continues until all four characters have been printed, whereupon unit 244 is set. This causes motors 221, 226 to be driven to their zero positions and to reset the whole system ready for the next seven groups of signals to arrive from the computer. A circuit is described which will detect incorrect positioning or omission of a holder in a bay, Fig. 6 (not shown).