Patent GB-154603-A (GB)
Abstract: 154,603. Felt & Tarrant Manufacturing Co., (Assignees of Turck, J. A. V.). Dec. 1, 1919, [Convention date]. Adding - apparatus; clear signals; zeroizing- mechanism.-Relates particularly to key-set-andoperated machines of the comptometer class, and comprises improvements in the zeroizing-mechanism described in Specification 148,292. The intermediate gear wheels 32, 34 transmitting motion from the receiving-pinions 31 to the numeral wheels 38 are mounted in a frame pivoted about the axis 35 of the wheels 34, the frame being swung forward, upon operation of the zeroizing-handle, so as to disengage the wheels 32 from the receiving-pinions and allow the transfer springs 41, Figs. 2 and 3, to rotate the gear wheels and numeral wheels back to zero. The forward movement of the zeroizing-handle effects the release of toggle members to swing the gear frame into the disengaged position, and may be accomplished by the use of the little finger only. The return movement of the handle is effected automatically under spring action, or by hand, leaving the gear frame in the disengaged position. Afterwards, upon the depression of any key the corresponding actuating-segment engages mechanism for setting the toggles, the gear frame being then swung back to the normal engaged position. At the same time a bell is rung to announce that the machine is ready for fresh calculations. The invention is described as applied to a machine having actuating and transfer mechanisms similar to those described in Specification 13094/04. The zeroizing-handle 71, Fig. 4, is connected on one side bv a link 101 to a pivoted member 102 controlled by a spring 104, and on the other side by a link 73 to a lever 74 connected to an arm 77 pivoted on a shaft 78. This arm 77 is adapted to engage an arm 80 to rock the shaft 78 when the handle is pulled forward, but is free to return with the handle without rocking the shaft. A number of arms 81, Fig. 7, fast on the shaft 78, are connected to slotted links 82 engaging the forked ends 85 of toggle members 86 pivoted on the swinging gear frame, the other toggle members 88 being pivoted on the fixed frame. The gear frame is so mounted that it tends to move out of the engaged position under the action of gravity, thereby lightening the action of the zeroizing-handle. Stop arms 92 are moved by the toggle members 86 into the paths of zero stop pins 97 on the wheels 32. The arms 81, links 82 and toggle parts 88 are omitted in alternate denominations, the corresponding stop arms 92 being positioned by the members 86. Pins 98 on the stop arms 92 engage the usual three-armed dogs to move them away from the transfer levers which are pivoted on the fixed frame so as to free the gear frame. The mechanism for moving the gear frame back to the engaged position comprises a transverse shaft 119, Fig. 2, connected by a link 118 and a toggle system 117, 110, 109, Figs. 3 and 8, with an arm 105 fast on the rock shaft 78. The transverse shaft 119 is adapted to be moved rearwardly, upon the depression of any key, by the tail of one of a set of levers 123, Fig. 2, having cam surfaces adapted for engagement by rolls 126 on the actuating segments. This action releases the toggle system, the final movement being effected by a spring 107. The return of the link 118 under the action of this spring gives sufficient impetus to a hammer 131, Fig. 3, journaled on the shaft 119 to sound a bell 130. The effort required to depress a key to restore the gear frame after zeroizing is greater than that required for normal actuation of the machine. The swing- ing movement of the gear frame during zeroizing imparts a slight rotation to the numeral wheels, so that the characters thereon are displaced from their normal position in the reading apertures, thus giving the operator an additional indication that zeroizing has been performed. Means are provided for preventing key actuation during zeroizing. A shaft 142, Fig. 2, having rearwardly extending arms, controls pawl members engaging the ratchets of the accumulator mechanism. Upon operation of the zeroizing handle this shaft 142 is rocked by the engagement of a lug 147, Fig. 4, on the lever 74 with an arm 146 on the shaft, and moves the pawls into engagement with the ratchets to lock the receiving pinions and therefore the actuating segments and keys. On the return movement of the zeroizing handle the pawls are disengaged by the action of other pawls restored by springs to normal position.