Patent GB-1239123-A (GB)
Inventor: HENDERSON EDDIE M
IPC: G06C11/06
Filed: 1969-01-13
Abstract: 1,239,123. Safeguard characters in accounting or book-keeping machines. BURROUGHS CORP. 13 Jan., 1969 [15 Jan., 1968], No. 1891/69. Heading G4B. An accounting or book-keeping machine (shown in Fig. 1) incorporates a safeguard character indexing mechanism (Fig. 2 &c.) for ensuring the printing of a safeguard character immediately to the left of the most significant digit of an amount being printed by the machine to prevent fraud, and comprises a plurality of type carriers 81 each carrying the type characters 83 from 0 to 9 and only the higher order carriers 81<SP>1</SP> carrying safeguard type characters 83<SP>1</SP>, type carrier positioning means responsive to keyboard indexing means and machine actuating means, and printing means including a plurality of spring-loaded hammers 85 releasable by hammer latches 111 to impact selected characters against an inked ribbon and a record medium; a solenoid 170 may be deenergized to prevent safeguard character printing. One of the type carriers 81<SP>1</SP> is depressed from a slightly raised zero position to bring its safeguard character 83<SP>1</SP> to the printing position, by engagement of the nose 187 of a slide 125 with a stud 109 on the type carrier, the assembly of slides 125 being moved (on rotation of a driveshaft 46 of the machine) towards and between the type carriers and then rotated so that the noses 187 descend to entrain the studs 109. Further studs 108 on the type carriers 81<SP>1</SP> and on the most significant carrier 81 (see Fig. 8) block the movement of the slides when the corresponding type carriers are in a zero or safeguard printing position. When any of these type carriers is raised to a non-zero printing position, the inclined carrier surface 184 cams the latch 111 about its pivot 113 to release at 117, 119 the corresponding hammer 85 and to block the movement of the slide 125 towards the type carriers 81<SP>1</SP>. Thus the most significant (e.g. sixth order) type carrier 81<SP>1</SP> carries its stud 108 upwards to allow the entrainment of the stud 109 of the next (i.e. seventh order) carrier to the left by its associated slide 125 to print a safeguard character, while higher order (eighth and ninth) carriers are not entrained since the studs 108 on said next and higher order (eighth and ninth) carriers are not moved out of their blocking position. The printing hammers 85 of type carriers 81<SP>1</SP> and 81 raised to non-zero printing positions are released from their latches 111 by the inclined surfaces 184 during such raising, and the printing hammer 85 of the type carrier 81<SP>1</SP> depressed (by its slide 125) to a safeguard printing position is released from its latch 111 by the inclined carrier surface 185 during such depression, but the hammers 85 of type carriers 81<SP>1</SP> and 81 in zero printing positions are released by the rotation of the latch 111 of the highest order hammer since all the latches 111 have leftward projections 121 to give zeros in the lower orders. The slides 125 are slidably cradled in a yoke 135 on shafts 127 and 129 and the yoke 135 is pivoted at 137 to a bracket 139. The drive-shaft 46 carries two cams 163 and 165, the initial (clockwise) rotation of the rod 46 causing cam 163 to rotate lever 163 which (via link 155) pivots a spring-loaded pivot member 145 further connected by springs 153 to the slides 125 so advancing the slides 125 towards the type carriers 81<SP>1</SP>, and the subsequent further rotation of the rod 46 causing cam 165 to engage roller 165 to rotate the slide assembly so that the slides entrain the one accessible stud 109. Keyboard indexing means.-Keys 21 (Fig. 1) are depressed, and a bail rod 43 is then moved rearwardly by rotation of a cam 45 (on the drive-shaft 46) acting on a three-armed lever 47, to permit stop slides 25 to be moved by springs 33 until limited by contact of stops 27 with depressed keystems 23. A stop sector 30 is connected at 31 to each stop slide 25 and rotates clockwise as the slide 25 moves rearwardly and a selected stop shoulder 35 on each sector 30 is thereby positioned in horizontal alignment with a lateral lug 37 carried by an actuator 59. The actuators 59 are released by movement of an actuator shaft 63 so as to be moved forwardly by the springs 57 into engagement with their respective stop shoulders 35. Each actuator 59 carries a slide 69 having teeth 65 which engage a gear train 76, 77 &c. engaging teeth 88 so that the type carriers 81, 81<SP>1</SP> are elevated to an extent determined by the movement of the keys 21. Each slide 69 is moved forward relative to its actuator 59 when the actuator abuts its stop shoulder 35, by the actuator shaft 63, and each slide 69 is locked in position by a pawl 71 thereon engaging a lockplate 73. The gear train 76, 77 shown in Fig. 1, is modified as shown in Fig. 6 to incorporate a one-way yieldable connection (allowing depression of a type carrier 81<SP>1</SP> from zero position) comprising studs 92 and 94 on gears 91 and 93 and a spring 95, and an additional shaft 105 carrying gears 101 and 103. When the lateral lug 37 of an actuator 59 within the safeguarded range of orders, is limited by the zero stop shoulder 35, the gear train is rotated to raise the type carrier 81<SP>1</SP> from its home position to its zero printing position. If subsequently the type carrier 81<SP>1</SP> is depressed from the zero position to the safeguard printing position, the studs 92 and 94 disengage against the bias of the spring 95 since the gear 91 is held stationary by the abutment of the lateral lug 37 with its stop shoulder 35. After printing of a safeguard character, the spring 95 restores the gears 91 and 93 to their home relative position.