Patent GB-491465-A (GB)
Abstract: 491,465. Calculating-machines. FAIRWEATHER, W. C. (Underwood Elliott Fisher Co.) April 27,1937, No. 11989. [Class 106 (i)] In a combined typewriting and computing machine arranged for sterling calculation and having differential-actuating rack bars provided with pins protruded by the numeral keys and later engaged by a reciprocating cross-bar to drive the rack bars, a lever is associated with the cross-bar and is rocked during the movement of the cross-bar, the lever acting through intermediate mechanism to give the pence rack bar the additional movement necessary in the pence denomination. The invention is shown applied to a machine of the kind described in Specification 411,291 in which each rack bar 31, Fig. 5, is advanced slightly in turn to bring the pins 29 beneath bars 27 lowered by the keys, this advance of the rack bars being controlled by the paper carriage. Idle pinions 36 permanently engage the rack bars, the totalizer pinions 45 being meshed with the racks for addition and with the idle pinions for subtraction. When the main shaft is operated, the cross-bar 53 moves to the left so that levers 64 pivoted at 66 to the cross-bar engage the depressed pins and differentially advance the rack bars. At the end of this movement the rack bar is stopped by the engagement of the depressed pin with an abutment 133 which at this time is moved to the right of the position shown to a point just behind the zero pin. In the present machine, the pounds and the units of shillings rack bars have each ten stops 29, Fig. 2, while the tens of shillings has two stops (zero and unity), the pence has twelve stops and the fractions of pence has four stops. The tens of shillings numeral wheel 39 has five " 1 " markings alternating with blank spaces. The pence numeral wheel 41 is double the standard width to allow " 10 " and " 11 " pence markings of the standard spacing. The pence fractions wheel has the marking 0 .. ¥ repeated three times. The totalizer pinions 46, Fig. 9, in the pence and pence fractions denominations have twelve teeth and are thus larger than the tentooth pinions 45 in the other denominations. The rack bars 30 in these two denominations accordingly have the pitch line of their teeth 32 lower than in the case of the other rack bars so that the pinions 45 and 46 may mesh simultaneously with their respective racks. The idle pinions 35 in the two said denominations are smaller than the other idle pinions 36 and the axis 83 of the smaller pinions 35 is lower than that of the larger pinions 36. The " 10 " and " 11 " pence pins are to the right of the row of all the " 9 " pins. During the idle period which occurs before the levers 64 on the cross-bar engage the " 9 " pins, the totalizers are meshed with the racks or the idle pinions. In view of the two additional pins on the pence bar, means must be arranged to provide this idle period in the pence denomination. Accordingly the pence rack bar 30, 100, Fig. 2, is not actuated directly but through an auxiliary bar 99 having a projection 98 extending beneath the pence bar into the path of any depressed pin. The auxiliary bar 99 has teeth 107, Fig. 9, engaging a sector lever 101 pivoted to the cross bar 53. During the initial movement of the cross-bar to the left, the lever 101 rocks clockwise until the part 109 engages the top of the cross-bar. The lever and the auxiliary bar are then carried along with the cross-bar, the projection 98 engaging the set pin in the pence rack bar 30. Since the normal movement of the cross-bar is sufficient to advance the rack bars through nine steps only, means are provided to give two extra steps to the pence bar. These comprise a lever 106 which engages a tail 103 of the lever 101 as the cross-bar nears the end of its leftward stroke. The lever 101 is thus rocked anticlockwise relative to the cross-bar and accordingly the auxiliary bar 99 and the pence bar are moved two steps to the left by the action of the lever on the teeth 107. When the cross-bar is returned at the end of an operation a fixed member 147 engages the lever 101 and restores it to its normal position. Transfer mechanism.-When a pounds wheel passes through zero a projection on the wheel depresses a lever 113, Fig. 5, to lift a slide 115 of next higher denomination above a bar 128, a spring 126 then moving the slide to the left to rock a lever 118 about its pivot 119. At the beginning of each operation, the bar 128 is moved to the right to rock the lever 118 clockwise away from a fixed stop 135 and to place the abutment 133 against the zero pins in the rack bars. When the slide 115 is tripped at transfer, it therefore returns to the position shown in Fig. 5 so that, as the cross-bar 53 completes its movement, the end 106 of the lever 118 is engaged by the end of the lever 64 and rocks this lever anticlockwise to give an extra or transfer step to the rack bar 31. The lever 64 is replaced in the pence denomination by the lever 101, Fig. 9. When transfer to the pence denomination occurs, the lever 106 which will in any case rock the sector to move the pence bar two extra steps is turned anticlockwise by means similar to those just described to a position in which it abuts against the lever 101 so early as to cause three extra steps to be given to the pence rack.