Patent GB-191028058-A (GB)
Title: Improvements in the Reversing and Transfer Mechanism of Calculating and like Machines.
Inventor: HOWIESON JOHN THOMAS
Filed: 1909-12-29
Granted: 1911-01-30
Abstract: 28,058. Howieson, J. T. Dec. 29, 1909. Adding-apparatus. - A single-bank key-set motor - driven adding- machine, formed as a computing - attachment to a typewriter, of which the denominationselecting and columnspacing mechanisms are described in Specification 3 0 , 4 2 6 / 0 9 , the differential actuating- mechanism in Specification 28362/10, and the spring-motor driving-mechanism in Specification 28,363/10, is provided with reversing-mechanism whereby addition or subtraction may be performed at will, and with two transfer mechanisms between each pair of numeral wheels, of which one only is operative at a time according to the position of the reversing-handle. Numeral-bearing elements. - The wheels 18, Fig. 51, of the counter are journaled so as to rotate loosely upon a squared shaft 29, which is also the main actuating-shaft, and consist of a flanged part 18 bearing the numerals, a transfer-actuating gear-wheel 19, a toothedwheel 20 for engagement with locking-pawls, and an annular wheel 22, which has external teeth 23 for receiving the transfers and internal teeth 24 whereby the numeral wheel as a whole may be clutched to the actuating-shaft. The operation of clutching any numeral wheel to the shaft disengages the corresponding locking-lever. Adding and subtracting. - The actuating- shaft 29 is driven from the spring-motor and its associated differential mechanism through alternative trains of gearing controlled by the reversing-lever. At one end of the shaft is provided a sliding gear-wheel 32, Fig. 24, with pins upon its face for engagement with holes in a broad wheel 34 driven by the motor through a wheel 36. The wheel 34 also engages with a wheel 39 upon an independent shaft, and this wheel in turn meshes with a wheel 41 which is fast to a wheel 44 by means of a sleeve and rotates upon a stub-shaft. When the sliding wheel 32 is positioned by the reversing-lever to the right, it is driven directly from the wheel 34 by the engagement of the pins and holes upon the adjacent faces, and in this position the sliding wheel is opposite the space between the gear-wheels 41, 44. Upon sliding the wheel 32 to the left, the drive proceeds from the wheel 34 by the wheels 39, 41 to the wheel 44, with which the sliding wheel is in engagement; the direction of the actuating-shaft is thus reversed. The reversing-lever effects the longitudinal movement of the wheel 32 by means of the arrangement shown in Fig. 25, wherein the handle 53 causes a rocking of the lever 146 and a sliding motion of the associated bail 141 and plate 52, of which the plate is provided with a curved slot engaging a pin upon a frame 45, slidably mounted upon a stub-shaft 46 and having an arm 48 forked for engagement with a groove in the hub of the wheel 32. The machine has two totalizing-counters, and each of these has an independent set of reversing parts and handle. Transfer mechanism.-The transfer actuating- gear of the lcwer wheel drives a gear upon a sleeve 78 mounted freely upon a fixed rod 79 and carrying two oppositely-arranged snail-cams 80, 81, Figs. 42 and 49. Each cam has upon one face a tappet finger 82, to which, respectively, the ends of a spring coiled upon the sleeve between the cams are attached; upon the opposite face is a lug 85 for engagement with an arm 86 keyed to the sleeve. The lugs and sleeve-arms are so disposed that, whether the machine is adding or subtracting, the snail-cam that has to effect the transfer is yieldingly rotated through the spring by the other cam, which is positively driven. The adding-cam presses rearwards a spring-controlled lever 110, pivoted at 93, and thereby withdraws a reciprocating transfer-frame 96, which is slotted for engagement with rods 90, 91 and carries the spring-depressed transfer-pawl 102, and also a rack 106 for engagement with a pinion upon the locking-pawl disengaging-shaft 123. This shaft carries a spring - controlled tappet 130, which, when the forward movement of the transfer-frame is permitted by the radial edge of the snail-cam, is rotated clockwise from the position shown in Fig. 49, in order that it may first depress the upper extremity 132 of the addition locking-lever 133, thereby disengaging the hooked end of the lever from the locking- ring 20 of the higher numeral - wheel immediately before the transfer-pawl comes into action, and, secondly, depress the locking-lever into operative-position again, ready to arrest the numeral-wheel at the end of a single unit movement, by contact with the projection 135, Fig. 34, thereon. In rapid operation, the snailcam might move in advance of the transferframe and thereby prevent this from completing the forward movement; to check the snail-cam in such cases, the tappet 82 upon the cam is arrested at the transfer point by the end of the arm 118 of the bell-crank stopping-lever 117 so long as the transfer-frame remains in its rearward position, wherein the rear end 108 of the frame keeps the cam projection 120, on the end of the rearwardly-extending arm of the stopping-lever, in raised position. The spring driving-connexion for the snail-cam renders this possible. A second identical transfer-mechanism for subtraction is arranged beneath the wheels, and the reversing-lever is provided with means for moving forwards or rearwards the two transverse bars 141, 143, Fig. 24, of which, in adjusted position, one is to the front and the other to the rear of their respective slots. The rearward bar locks the transfer-frames against movement, and disengages the transfer-pawl, while during the movement of a bar the numeral wheels are locked against movement owing to the engagement of both transfer pawls.