Patent GB-1299744-A (GB)
Title: An adding, subtracting and totaling calculator
Inventor: OBA HARUTARO
IPC: G06C15/04
Filed: 1970-02-06
Abstract: 1299744 Calculating machines TOKYO ELECTRIC CO Ltd 6 Feb 1970 [6 Feb 1969 (3) 10 Feb 1969 (2) 4 Sept 1969] 5886/70 Heading G4B The invention relates to the totalizer tens transfer mechanism and to other features of a calculating machine. Setting means.-Depression of any key 19 except the "9" key, Figs. 1 and 3, acts through a stem 19α-19i to depress a corresponding pin 4 in a sliding carriage 3 and also pivots a frame 20 about rod 20a so that a stem 21 depresses the "9" pin. The "9" pins, in conjunction with a stop 12, Fig. 6, control the order-by-order escapement of the carriage. The carriage may be returned to its starting position against spring 11 either manually, through member 15, or automatically by a cam-operated lever system, Fig. 4 (not shown), acting on linkage 16, Fig. 3. The cam-operated lever system may be moved out of co-operation with linkage 16 to prevent the automatic return of the carriage and clearing of pins (by member 17, Fig. 6) so that repeated additions or subtractions may be made. Depression of a function key moves plate 23, Fig. 3, into engagement with slots 26 to render the digit keys inoperable. Differential actuators.-Each order has a rack 5a, Fig. 1, which is spring-urged to the right until stop 30a abuts a set pin 4. These racks set an indicator and printing assembly 6. A second rack 5b is connected, by pins-and-slots to each rack 5a. Due to the pin-and-slot connection and a spring 35, racks 5b do not move with racks 5a until the latter have moved through one tooth pitch. On the return stroke of the racks, either the add or subtract pinions of totalizer 7 are engaged with and rotated by racks 5b until a stop pin 44 abuts a lever 41. Tens transfer.-If a carry pawl 39a of an order of the totalizer trips a lever 40, lever 41 is pivoted clockwise by a spring 41b to present a step 41c towards the stop pin 44 fast with rack 5b of the next higher order. This allows the rack one extra tooth pitch of return movement to effect the carry. "Fugitive one".-When the highest orderpinion of the totalizer moves through zero, a lever 101, Fig. 12, similar to carry levers 40, Fig. 1, is tripped to allow the fall of lever 102 formed   with a step 102b. Lever 102 is associated with the lowest order of the totalizer and step 102b permits one extra tooth-pitch of movement to the lowest order rack 5b. The rest of the mechanism shown in Fig. 12 is concerned with the display of either a positive or negative sign, when the "fugitive one" mechanism operates, to indicate whether the subtract or add side of the totalizer holds the true total value. Totalizers.-The angular position of the totalizer sectors and their proximity to the racks are controlled by the function keys acting through linkages, Figs. 9 and 10 (not shown). Two separate totalizers may be provided, Fig. 13 (not shown), each tens transfer lever of the second totalizer being pivotally connected to the corresponding order transfer lever of the first. Non-significant zeros.-The racks 5 of orders higher than the highest order of the number set are prevented from movement by an edge 135a, Fig. 3, of a plate 135, the latter being movable with the pin carriage. With the carriage in its home position, a lug 135b of the plate rests on a fixed bar 138 to keep the plate raised in an inoperative position. Drive.-The main shaft of the machine is driven by an electric motor through a clutch, Figs. 14, 15 (not shown), which disengages automatically after one revolution.