1434890 Ink ribbon mechanisms VICTOR COMPTOMETER CORP 22 May 1974 [17 Sept 1973] 22864/74 Heading B6F A printer has an ink ribbon 24 fed via guides 25 between spools 21 which are on a deck 11 pivotally supported at 13; one of the ribbon spools 21 is driven via its associated ratchet wheel 17 engaged by a pawl on oscillating arm 64 and a vibrator mechanism pivots the deck 11 from a lower inoperative position to first or second upper operative positions. Vibrator mechanism.-As shown in Fig. 4 a link 29 is pivoted at 29 to lever 33 and has its free end resting on cam 35 having two tracks of different diameter, each track having a dwell 37, 38. In the printing of a line cam 35 rotates once anti-clockwise and then reverses back to its starting point. If solenoid 47 is not energized as shown, the link 29 follows the smaller diameter track causing the link to rise as far as the phantom position. When the solenoid 47 is energized the link follows the larger diameter track by means of extension 39 and so produces a greater range of movement. The link 29 is connected to the deck 11 by stud 28. The different ranges of movement permit the use of a two colour ribbon. Ribbon feed and reversal.-During clockwise rotation of the shaft 36, cam 52 or cam 51 is also rotated, so rocking a bell-crank 54 to move a slide 59. The slide 59 in turn carries a pin 63 engaging one of the two notches 65 in pawl arm 64. Thus oscillation of the slide 59 indexes one of the wheels 17. When the supply spool is emptied, the take-up spool will no longer rotate and thus, at the next feed stroke of the arm 64, springs 66 guide the arm 64 so that the pin 63 engages the other notch 65 thereby reversing the drive to the spools..
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