Patent GB-190005322-A (GB)
Title: Improvements in Calculating Machines.
Inventor: MALLMANN JAMES
Filed: 1900-03-20
Granted: 1900-05-19
Abstract: 5322. Mallmann, J. March 20. Type-writers and like machines.-Relates to calculating- apparatus in which the detail numbers and their sum are printed in a column. The apparatus is " set " for each number to be added by pressing a pointed tool, pencil, or the like into the proper tooth r, Fig. 3, of a bar p and sliding it to the left until the tool is stopped by the edge of the opening b. There is a separate bar for each denomination (units, tens, &c.) and the teeth are numbered from 0 to 9. Adjustable longitudinal bars may be placed across the opening b to distinguish the millions, thousands, &c., and act, where necessary, as a decimal point or to separate cents and dollars. A slight movement is given, even in registering zeros, so that the number set up can be read off along the edge of the opening b to avoid mistakes. The teeth s, by means of ratchetwheels x, actuate the counting-wheels w, showing through the apertures c, as the bars move to the left, spring pawls 6 preventing back movement on the return stroke ; the teeth t engaging pinions 41, set the type-wheel 40 for printing the items ; the teeth u, engaged by spring pawls 44, hold the bars in position during the printing operation. To print each item, the shaft 14 is rocked by an external handle, and, through the crank 16 and link 17, swings the levers 20 carrying the cylinder 23 and feed-roll 26 so as to bring the paper strip passing between the former and the clip 24 against the type-wheels. The paper strip is drawn from a spool 73, and, in the return stroke, the cylinder 23 receives a slight rotation by means of a pawl and ratchet feed, not shown, so as to space the lines of figures printed. Spring levers 34 carry an inking-roller 35, which inks the type as they are being set up, but moves out of the way when the impression is being taken. A spring pawl 49 and auxiliary pawl 52 engaging a cross-bar 47 pivoted at 48 swing its upper end backwards during the return of the link 17, and, releasing the pawls 44 from teeth u, allow the springs 45 to draw back the bars p to normal position. The type-wheels are thus zeroized, but not, of course, the adding-wheels w. To print the total, an external finger-piece 68 is depressed, turning the bar 62 on its axis 63 and lifting all the bars p so that they cannot engage the ratchet-wheels x. The bars p can then be set according to the total shown on the wheels w, and the printing-mechanism actuated as before. In this case an additional feed of the paper is effected by hand. To use the adding-mechanism. when desired, without printing, the push 61 is pressed down ; this rocks the bell-crank lever 59, which is connected by a link 58 with the bar 47 so that the pawls 44 are disengaged from the teeth u, and the bars p can act independently. For '' carrying" between the wheels w, a series of discs y, Figs. 11 and 12, are fixed on the axis v, the flattened portions of which allow spring pawls 3 to engage one tooth of the ratchet-wheel x of the wheel of next higher denomination once every rotation. For zeroizing the counter, the shaft v is turned forward and then back, the movement being controlled by a stop mechanism under the control of a pushbutton, not shown. In the forward movement, studs 1 on the discs y pick up spring arms on the wheels and turn them to zero. To prevent overdriving, teeth may be formed on the counting- wheels w, with which flat springs engage to check the movement at the required point.