Patent GB-190007172-A (GB)
Title: Improvements in Computing or Calculating and Recording Machines.
Inventor: DAY CHARLES AUBREY
Filed: 1900-04-18
Granted: 1900-08-11
Abstract: 7172. Day, C. A., [Shattuck, W. P.]. April 18. Type-writers and like machines.-Relates to keyboard apparatus for printing columns of figures, such as the values of cheques, and their total. Corresponding to each row of keys 7, Fig. 3, is a screw shaft 23 mounted in a carriage 15, which, when any number has to be registered is drawn forward to the front of the machine and pushed back again by means of the handle 19. The depressed key in each row engages the thread of the corresponding screw shaft 23, and rotates it through an angle proportionate t o the number marked nn the kev button. Normally the screw shafts are locked by a pivoted spring plate 31, which engages a pin 35 but is thrust aside by the depressed key just before the screw shaft reaches it. The keys are returned, on the back movement of the carriage, by the action of a slip pawl 14 on a bevelled lug 12, depending from a plate 6, which is raised by pins and slots 8 and forces up the projections 9 on the sides of the keys. When it is desired successively to repeat the same number, the pawl 14 is thrown out of action by depressing a key 233, and the keys then remain depressed after each actuation of the apparatus. The movements of the screw shafts 23 are communicated to ten toothed worm-wheels 45, which are connected by sleeves to separate item-printing type-wheels 47, Fig. 21. These typewheels return to zero on each backward movement of the carriage ; the type-wheels 49, however, are for printing totals and must therefore be continuously advanced. For this purpose, they are mounted loosely on the shaft 23 carried by rocking arms 61 having an extension arm 67. A pin 73 projects from this arm into one or other of the slots 71, 69 in the casing of the apparatus. During the forward movement of the carriage the pin travels in the slot 71, and the wheels 49 are held in engagement, as shown in Fig. 21, with the idle transfer wheels 75, so as to receive movement from the wheels 47. At the end of the forward movement the pin 73 is switched into the slot 69, and, in the back stroke, travels along it so that the wheels 49 are held out of gear with the wheels 75 but in gear with locking detents 50. When the actuation has been completed, the pin is switched back again into the slot 71. " Carrying," on the type-wheels 49 is effected by mounting the transfer wheels 75 in vertically-moving standards 79, normally held in their highest position by hooks 97 on levers 95 but having springs 99 which tend to depress them. Whenever in the forward movement of the carriage a wheel 49 moves from 9 to 0, a pin 103 trips the lever 95 of the wheel of the next higher denomination, the standard 79 is pulled down by its spring until it rests upon the cross-bar 89, and the wheel 75 gives a one-step movement to the next type-wheel 49. During the return movement of the carriage, when the wheels 49 are out of gear with the wheels 75, the crossbar 89 runs over the pivoted inclines 101, under which they passed in the forward movement, and the standards are raised and re-engaged by their hooks. "Zeroizing" is effected by turning the shaft 53 in the direction of the arrow. Discs 55 fast to the shaft carry spring dogs 59, which pick up pins 57 on the type-wheels 49 and turn them forward to zero position. The rotation of the shaft 53 is caused, on the backward movement of the carriage, by a toothed wheel upon it engaging a fixed rack. Normally the wheel is locked by a spring lever, and the rack, which is mounted on a rock-shaft, is out of gear; but on depressing a special key 86, Fig. 1, marked " o," the lever is thrown back and the rack turned into position to engage the wheels. The record paper strip is wound on a spool 145, Fig. 1, thence carried round a diagonal spindle 141, through a guide 149, over the feed-roller 135, and between this roller and the feed-roller 137. The feed-rollers are mounted in a frame 139 secured to the ends of the diagonal spindle 141. 169, 171 are spools for the transfer ribbon 167 which is looped over a wire so as to cover an aperture in the casing beneath which the type-wheels 47 or 49 are brought according to whether an item or a total is to be printed. The printing is effected, after bringing the type-wheels into position, by pressing down the handle 19 ; this rocks the shaft 107, depresses a rack, not shown, gearing with a pinion at the end of the shaft 141 and throws the whole frame 139 over so as to press the paper strip, where it passes over the feedroller 135, upon the transfer strip 167 and the type-wheels beneath it. The position of the carriage for printing items or totals is determined by the arrangement shown in Fig. 19 ; normally the carriage can be pulled forward its full distance, a pin 113, on the arm 109 projecting from the shaft 107, running in a groove 115. When the handle 19 is pulled down the pin 113 travels down the groove 117. To print a total, the key 125 is depressed, and turns the little turn-table 123 so that the stop 121 is brought into the path of the pin 113 ; the carriage can then be pulled forward a part only of its full stroke and on depressing the handle 19 the pin 113 runs down the groove 119, the mouth of which is now open. Cams on the shaft 141 operate a lever carrying cross-bars by which the type-wheels are brought into exact alignment. A ratchet-wheel on the spindle of the feed-roll 135, when it is thrown over to take an impression, strikes a pawl pivoted to the casing and causes the feed of the paper strip. The transfer ribbon spools 169, 171, have ratchet-wheels, with one of which engages a pawl on a slide reciprocated by the movement of the carriage ; the pawl can be engaged with either ratchet-wheel by hand so as to feed the strip in either direction. In order to prevent meaningless ciphers being printed to the left of any number, a spring slide is carried over the type-wheels when in printing position. Its movement is regulated by a rod which passes through holes in the type-wheels lying in a straight line when the wheels stand at zero. The rod is arrested, however, by the face of the first wheel that has been displaced.