Patent GB-632225-A (GB)
Abstract: 632,225. Calculating-apparatus. FELT & TARRANT MANUFACTURING CO. April 14, 1947, No. 9855. Convention date, Feb. 5, 1943. [Class 106 (i)] In a power-driven, normally keyresponsive calculating - machine having a number of ordinal columns of depressible digit keys, and a multi-denominational accumulator and actuator therefor, latching means is provided to hold the digit keys in partially-depressed key-set position, each latched key being reciprocable between the partiallydepressed position to a completelydepressed position to control the operation of the accumulator, and setting means is provided for selectively rendering the latching means effective or ineffective. Mechanical means for collectively shifting the setting of the partiallydepressed digit keys of the various ordinal columns to the next adjacent respective ordinal columns either to the right or left is provided. Multiplication and division is by repeated depression of the digit keys by means of a handoperated crank in known manner. The machine described is a keyresponsive, power-driven calculating machine of known type. The digital keys 24 of each column control the rotation of an accumulator actuating pinion 26. Each denominational element of the actuator is permanently aligned with one denominational order of the accumulator. When a key is fully depressed, adjacent anchorshaped locking members 90, Fig. 2, are rocked to engage apertures 85, Fig. 4, in the keys to prevent full depression of any other key in the same order. When a key 102 is depressed, the machine is keyresponsive until this key is released by depression of a control key 101, when the machine is then conditioned for key-set, crank-operated multiplication and division. The key 102 is maintained depressed by a spring-urged lock piece, pivoted on a, transverse shaft 104, Fig. 9, which enters a notch 108 in the key stem 100. An arm 109 on the lock piece has a pin 111 thereon disposed in a notch in the stem 110 of the key 101, so that when the key 101 is depressed the lock piece is rocked to release the key 102. The keys 24 can be partially depressed and retained in that condition to facilitate division and multiplication. A spring-urged longitudinal latch bar 114, Figs. 2 and 4, adjacent each row of keys 24, is mounted for pivotal movement in brackets 115, 115<SP>1</SP>, and is formed with latch arms 118 adapted to engage under projections 119 on the key stems 47, when the keys are raised, and to engage in notches 122 in the stems when the keys are depressed to hold them depressed. If, however, the key 102 is depressed, the latch bars 114 are rocked and maintained out of engagement with the key stems 47 by means of a laterally shiftable release bar 123, Fig. 9. A pin 127 on the bar 123 is engaged by a pivoted lever 128 having an extension 132 disposed in the notch 108 in the stem 100 of key 102, so that when the latter is depressed, the latch bars 114 are rocked away from key stems 47 and the machine is then key-responsive. When the key 102 is released by depressing the key 101, the digit keys 24 thereafter depressed are maintained in partially depressed position. Where a wrong key in any order has been depressed, partial depression of the correct key will cause the latch bar 114 to rock and release the first key, and the correct key will be retained depressed by the latch bar. The anchor-shaped locking-members 90 for the key stems and the apertures 85 in the latter are dimensioned to allow such partial depression of the keys. The partially-depressed keys 24 are repeatedly fully depressed by rotating a crank 133 (not shown) which drives a longitudinal shaft 134, Fig. 4, geared to transverse shafts 155, one for each transverse set of keys 24. A notched cam on the shaft 134 and a co-operating spring-urged lever enables each complete rotation of the crank to be sensed. Each shaft 155 has thereon single-toothed discs 157, one for each key stem 47 of the associated set of keys, disposed opposite slots 158, 159 in the key stems. The teeth 160 of the discs are staggered to ensure smooth operation of the machine. If a key is partially depressed, the tooth 160 will engage the bottom edge of the top slots 158 to depress completely the key and then release it. A ratchet and pawl device ensures only clockwise rotation of the crank 133, but a release means can be operated to allow counter-clockwise rotation. Means for shifting the multiplicand or divisor from one denominational place to another to vary the denominational value of the partially-depressed keys comprises a shift-key 175 (not shown) slotted to receive a pivot stud, and provided with a forked end to engage over a pin on a pivoted plate. This plate is rotated, on depression of the shiftkey 175, against the action of a snap spring which completes the rotation of the plate and returns the key to the raised position which is angularly disposed to the prior raised position. A sector gear 188 (not shown) rotated by the pivoted plate, moves laterally a rack-bar which, through sector gears, rocks longitudinal shafts 198, Figs. 2 and 4. A shaft 198 is provided between each two adjacent rows of keys 24. Two keys 209, 211, Fig. 9, to cause denominational shifting for multiplication and division. respectively, when depressed, have projections 213 on their stems 212, 212<SP>1</SP> adapted to rock levers 217 pivoted on the shaft 104 to cause movement of end brackets 186, 199, Fig. 2, carrying the shafts 198 so that the latter are moved rearwardly to position key-shifters 208 thereon in engagement with any keys positioned to receive them. Each key-shifter 208 is notched and normally pressed by a spring 228 into engagement with a pin on the shaft 198, and has left and right fingers 231, 231<SP>1</SP>, Fig. 4, adapted to engage shoulders 232 on opposite key stems 47. As shown in Fig. 4, the partially-depressed key allows the right end shifter 208 to enter between the two keys so that the fingers 231, 231<SP>1</SP> engage over the shoulders 232 on both key stems. Rotation of the shafts 198 by one of the keys 209, 211 in a clockwise direction will cause the end key to be partially depressed to a position where it will be retained by latch arm 118. Oppositely-disposed projections 223 on the key stems 212, 212<SP>1</SP> are adapted to engage pins 224 on the ends of a lever 225 secured to one shaft 198, Fig. 9, to rock all the shafts 198, in one direction or the other, according to which key 209, 211 is depressed, to cause the denominational shifting. Since two keys in one order cannot remain depressed, the previously depressed key is released. Where no figure of value is to be shifted into a denominational order in which a key 24 is maintained partially depressed, means is provided to remove the latch arm 118 from the partially-depressed key to allow it to rise and for removing all the latch bars 114 through the medium of the shiftable transverse release bar 123, whereby all keys not held by the shifters 208 can rise. This means comprises a pin on the bar 123 adapted to be engaged by a pawl 235, Fig. 9, pivoted on a pivoted lever 236 having projections 242, 244 engaging under shoulders 245, 243 respectively, on the keys 209, 211. The means for locking the machine in the event of a partial key stroke insufficient to cause a power action, is of known kind generally, but is modified so that, upon depression of a shift-key 209 or 211, the digit keys 24 are locked against any but limited vertical downward movement sufficient to be latched in a partially-depressed position by latch arms 118. The movable brackets 186, 199 carrying the shafts 198 are connected by a link 221 (not shown) having a leg adapted to trip a pivoted lever which rocks a notched shaft 261, Fig. 2. This shaft rocks a lever 264 to raise a lever 248 connected thereto to suitably modify the positions of a tooth 247 or teeth 260 in relation to error control dogs 246, 246<SP>1</SP>. Operation. To perform multiplication, the key 101 is depressed to render the machine keyset, keys 24 corresponding to the multiplicand are depressed and automatically retained in a partially-depressed condition, the key 175 is depressed and moved over to the right, and the crank 133 rotated a number of times corresponding to the digital value of the units order of the multiplier less one (since the multiplicand has already been entered by the manual setting of the keys 24). The key 209 is then depressed to move the value of the multiplicand to the next higher order, the crank rotated a number of times equal to the digital value of the tens order of the multiplier, and so on. For division, the key 102 is depressed, the keys 24 representing the dividend depressed to enter the dividend in the accumulator, and the key 101 is depressed to release the key 102 and condition the machine for key-set actuation. The key 175 is depressed and moved to the left, and keys 24 representing the complement of the divisor are then completely depressed and retained in partiallydepressed position. The crank 133 is then rotated until the number of rotations thereof (counting the initial manual depression of keys 24 as one rotation) coincides with the changing leftmost figure of the' value contained in the accumulator, and the operation completed in known manner.