Patent GB-279423-A (GB)
Abstract: 279,423. Friden, C. M. F. Oct. 25, 1926, [Convention date. Multiplying and dividing apparatus. -In a power-driven machines for the four rules having means for setting both factors and a reversible differential actuating-means for the totalizing- counter, means, under the control of multiple keys, is provided to determine the direction and duration of movement of the actuators. The said keys may be arranged in two banks one for movement in the positive direction and the other for movement in the negative direction or a single bank of multiplier keys may be provided associated with a special key for reversing the direction of movement. The machine to which the invention is shown applied is similar to that described in Specification 229,642. The motor drive for the shaft 12, Figs. 1 and 8, the clutch 9 mounted thereon, and the reversing gear 21, 24, 25 for the rotary actuators 7 function as described in the aforementioned Specification. Keyboards.-In one form, as shown in Figs. 1, 5, and 14, the means for determining the number of operations of the actuators in a forward or reverse direction comprises two key banks 41, 42 each provided with a clearing key 43. The cam lever 28, which is adapted to shift the reversing pinion 21 by engagement with a recess in the shaft 19, is connected to a link 47 pivoted to a spring controlled rock lever 46 normally in position to effect a forward drive. On depression of a key 41 the lever 46 and cam lever 28 maintain their position but on depression of a key 42 the levers are moved to reverse the drive. Each key 42 is provided on its stem with a cam projection 52 engaging a corresponding notch in a slide-bar 54 so that on depression of any key the bar is moved forward and a pin 55 thereon rocks a lever 56 to cause a bar 58 pivoted thereto to displace the link 47 and cam 28. Each of the keys 41, 42 is provided with a projection 69 co-operating with a slide bar 71 in such a manner that when a key in either bank is depressed the bar 71 is moved rearwardly to rock a gate member 67 to which is attached a finger 66. This finger engages a pin 65 on the clutch contral bar 63 so that movement of the finger causes the bar 63 to rock the clutch lever 35 and render the clutch operative. The key stems in each bank are disposed above a pair of levers 73, 75 pivoted at their outer ends and connected together at an intermediate point 77, Fig. 9, the forward end of the lever 75 being in alignment with the rear end of the lever 73 so that one or other of the levers is engaged by the kev stems. The two levers 73 are connected at their rear ends and are slotted to receive a pin 95 extending from a lever 96 pivoted to the frame of the rotation controlling unit, Fig. 13, similar to that described in the above-mentioned Specification. The lever 96 carries a pin 98 which engages a slot in a lever 90 pivoted to a rack bar 84, the lever 96 being moved to position a pin 86 on a projection thereof opposite one of a number of steps on a plate 81 depending on the value of the key depressed. A tooth 85<a> on the clutch housing through a pinion 85 moves the rack step by step until the pin 86 engages the step presented to it whereupon on the subsequent or final movement the plate 81 is moved and a fixed projection 89 rocks a cam lever 88 pivoted on the slide 81 and through contact with a pin 91 on the clutch control bar 63 moves the bar 63 out of engagement with the clutch lever 35 to throw out the clutch. Detent bars 103, 104, Figs. 3 and 5, are provided to hold the depressed key 41 or 42 in position. The bars are connected by a screw link 105 and the bar 104 has an extension 106 co-operating with one arm of a bellcrank lever 108 connected by a link 109 to the slide 81 so that when the slide is moved as above described the lever 108 operates to release the depressed key. The " 1 " key of each bank is not adapted to coact with the detent bars but either key on depression sets the lever 90 to the " 1 " position and initiates the operation before the key returns. The final movement of the lever 90 through a lever 112, Fig. 13, engaging a pin 14 on the rack bar latch 87 frees the rack to permit its return to normal position. As in the prior invention, starting control keys 121, 122 are provided which co-operate with a rocking plate 123 connected to the clutch control bar 63 and with the rocking plate 46 connected to the link 47. Depression of the key 122 has no effect on the plate 46 but the key 121 rocks the plate to reverse the drive. The drive may be limited to one rotation or continue as long as either key is held depressed. For this purpose a key 124, Fig. 10, is provided, said key being depressed for addition and subtraction operations. The key stem has an arm 128 attached thereto which overlies the key lever 75 of the key-bank 42 so as to set the lever 75 and consequently the lever 90 to the " 1 " position. A " clear " key 127 is provided to release the key 124 and the ordinary keys 132 of the keyboard. The key latch-plates have an upturned end 134 engaging a gate member 135 and a lever 136 in contact therewith is operated on depression of the key 127 to effect the release movement of the latch-plates. When the key 124 is depressed a lever 139 is rocked and a projection 141 thereon raises the end of a lever 138 into an operative position with respect to the gate member 135 so that at each rotation of the pinion 25 the member 135 is operated to release the depressed keys. With the key 124 in its raised position the lever 133 moves idly'and the keys are not released. In a modification a single bank of multiplier keys and a single reverse key is provided, the reverse key being connected through a bell crank lever and a link with the link 47.