Patent GB-705491-A (GB)
Title: Calculating machine
IPC: G06F7/46
Filed: 1949-10-27
Abstract: 705,491. Digital electric calculating-apparatus. BRUNI, R. Oct. 27, 1949 [Oct, 30, 1948], No. 27611/49. Class 106 (1) In an electric calculating machine having counting wheels forming an accumulator and arranged to register a result or partial result of a calculation, and at least one control electromagnet for each counting wheel, the electromagnets permitting the wheels to remain coupled to a driving shaft during a portion of rotation corresponding to the digit to be accumulated, operator-controlled digit contacts are arranged in the electromagnet circuits with interposition of at least one commutator having a rotatable brush and a series of electric contacts, and the brush rotates when the driving shaft rotates and explores for each electromagnet the digit contacts (of which only one set, or a separate set for each counting wheel, may be provided), the circuit of at least one electromagnet being closed by the commutator when the angular position of its brush corresponds to the value of the selected digit contact associated with this electromagnet, so that each counting wheel is rotated over an angle corresponding to this value. General operation; addition and subtraction.- Fig. 1 illustrates the principle of the invention. The totalizer comprises denominations a, b ... n called "counting devices each having a numeral-indicating member 8 which is frictionally driven by a member 6, continuously rotating with a motor-driven shaft 2, unless restrained by an electromagnetically operated plunger 30. To enter a number, keys 38 are depressed to close corresponding contacts and then a key ACC. When the continuously rotating brush 20 of a commutator CH engages the "O contact, the circuits are completed to windings 26 which operate the plungers 30 to initiate rotation of all the members 8. The plungers are returned by energizing windings 34, connected to the columns of key contacts, at a differential time depending on the keys depressed, all the "1" keys being connected to the " 1 " contact of the commutator and so on. In subtraction, the shaft 2 is rotated in the reverse direction and the keys 38 representing the tens complements are depressed. In the machine shown in Figs. 2 and 3, each member 8 has ten notches 94 one of which is normally engaged by a tooth 54 on a lever 46. A frictional coil spring 10, wound around the member 6, Figs. 3 and 5, has its ends engaging recesses in the member 8. When an electromagnet 76 is energized it rocks a lever 78 so that a spring-urged lever 80 pushes a pawl 70 out of engagement with the lever 46 which is then rocked by a spring 60 to permit member 8 to rotate. A second energization of the electromagnet similarly disengages a pawl 72 from a lever 48 which is then spring-rocked so that a tooth 56 engages a notch 94 and stops the rotation. The lever 46 is returned to the position shown by a cam 86 on the member 6 engaging a nose 84 of the lever. An axle 92 is rocked, once for each cycle or rotation of shaft 2, by a pin 100, Fig. 5, engaging an arm 96, and is also shifted against a spring 114, by a cam projection 102 and a lever 106, into a left position in which it may be retained by a spring-urged pawl 118, Figs. 2 and 6, having a shoulder (not shown) engaging part of the machine frame, in which case this rocking causes arms 90 to engage pins 88, Fig. 3, and return the levers 48. If, however, the pawl is held down by a spring- urged lever 124, as shown in Fig. 6, the rocking of the axle 92 is ineffective and no further actuation of the totalizer is possible. The arm 96 rocks, through levers (not shown), a shaft 156 which then raises by an arm 150 levers 130, 132 pivoted on the lever 124 and connected by a spring 134. The lever 132 is then held by a pin 148 thus retaining lever 124 away from the pawl 118. The lever assembly is returned by an electromagnet N whose armature engages the lever 130. The commutator CH comprises a continuously rotating disc 164 carrying a brush 166 which co-operates with contacts 172. To add a number into the totalizer, the digit keys, Fig. 2. are depressed and close contacts 206, Fig. 8, in the banks Ia ... In corresponding to counting devices a ... n respectively, and additional contacts ia ... in. After key ACC is depressed a circuit is therefore completed from battery 190 through the " 0 " contact of the commutator and normally closed contacts 177, 176 and 179, 180, Fig. 3, to the electromagnets 76. The rocking of pawl 70 closes contacts 176, 178 so that the second energization of magnet 76 is through the circuits including the commutator and digit contacts and conductors 198. If any of the members 8 pass through the " 0 " position a projection 182 rocks a lever 184 which is held by a latch 186 and closes contacts 1, 3 and 4, 5 of a transfer switch ha ... hn-1, Fig. 8. Contacts 1, 3 of switches ha .. hn-1 connect the magnets 76 of the next higher counting device through conductor 202 to the commutator contact "9" so that rotation of the members 8 begins one unit earlier at the next addition. If no subsequent normal addition is effected, when key ACC is released, relays D, T are energized, the latter being slow-operating. Contacts 3, 4d byepass contacts 1, 2 acc to effect addition of transfers, the magnets 76 being energized to stop the members 8 when the brush 166 reaches " 0 " by circuits through the " 0 " digit contacts which are closed when no digit key is depressed. The contacts t of relay T close a circuit to a magnet P which rocks the latches 186, Fig. 3, to return the transfer switches to normal. Repeated operations due to prolonged depression of key ACC are normally prevented by energization of electromagnet N, Figs. 6 and 8. For subtraction, a key Z, Figs. 2 and 8, reverses the rotation of shaft 2 and makes tens-complementary connections between the commutator and digit contacts. Multiplication.-To multiply a number by a single digit, the number is set up as before ard the key in the right-hand column, Fig. 2, corresponding to the multiplier digit is depressed thereby closing contacts 220, Fig. 9, in a bank Ix and contacts ix. A key ENRx is depressed and when the commutator brush is at " 0 " a circuit is completed through a switch J to the magnet 76 to start a rotary counting switch x similar to the devices a ... n but including a rotary brush 212 and associated series of contacts. When the brush reaches the contact corresponding to the multiplier digit it is stopped by a second energization of the magnet through a circuit including conductor 222. A key ACCx is then depressed and a relay U is energized which actuates key ACC, Fig. 8, opens contacts 1, 2u to prevent energization of magnet N, and rocks pawls 70, 72 of switch x (see Fig. 3), the member 8 then being held by the lever 48 which is rocked once per cycle by the arm 90 to allow the switch to step on one unit. Repeated additions then occur until the brush 212, Fig. 9, reaches "0" when a relay Y is energized, through contacts 1, 2 enr x, and 3, 4 acc x (both closed by key ACCx), and opens contacts 1, 2y to de-energize relay U, and thereby allow magnet N to be energized to prevent further totalizer operations. In order that more complex multiplications may be effected, a carriage, Figs. 2 and 3, transversely shiftable on bars 232, carries numeral-indicating drums 236 half of which are normally geared to the totalizer members 8. A multiplication by one digit is made with the carriage in a halfstep position out of register with the totalizer, and the carriage is then shifted and the result transmitted to the drums 236 at the same time as the totalizer is zeroized. These operations are effected by depressing key ACch, Figs. 2 and 10, which completes a circuit to an electromagnet V which operates the key ACCx, Fig. 9, described above. When the brush 212 reaches "0", contacts 1, 2ex, Fig. 10, are closed and a relay K is energized and opens contacts 1, 2k in the circuit of magnet V. When transfer operations have been completed relay D, Fig. 8, is de-energized and contacts 7, 8d, Fig. 10, are closed to energize relay S through closed contacts 1, 3k. Relay S closes contacts (not shown) to shift the carriage into driving connection with the totalizer and reverse the rotation of shaft 2. Contacts 10, 11s are opened to de-energize relay K so that a circuit is completed through contacts 1, 2k and 1, 3s to magnet RZ which operates the zeroizing key RX, Figs. 2 and 3, which closes switches ia ... in, "0" contacts of la .. In and contacts 1, 2 acc through connections (not shown), and rocks arms 50 having teeth which engage indentations 66 in the members 8 when they reach zero, contacts 1, 2ea ... 1, 2en, Fig. 10, then being closed to energize a relay M. If any of the carriage drums 236 pass through zero when the amount on the totalizer is transmitted thereto, corresponding contacts hca ... hcn-1, Figs. 8 and 10, are closed and a circuit is completed through the now closed contacts 1, 3m of relay M to a magnet G which switches over contacts go ... gn, Fig. 8. The magnets 76 for the counting devices which are to receive transfers are then connected through contacts 1, 2hca ... hcn-1 which replace the switches hgh ... hn-1 to the conductor 202 After the transfers have been transmitted to the carriage, magnet P is energized and closes contacts 1, 2p, Fig 10, to energize relay R which opens contacts 1, 2r to release magnet G and relays M and S. This causes a shift of the carriage to the out-ofregister position in which contacts 1, 2ch are closed so that another circuit is completed through contacts 1, 3r to the zeroizing magnet RX. The release of key ACCch then returns the machine to normal. The carriage may be replaced by additional counting devices and switches which connect the columns of key contacts successively to a different group of counting devices. The counting devices may actuate a typing or punching device. Modifications.-Various mod