Patent GB-369891-A (GB)
Abstract: 369,891. Calculating-apparatus. MARCHANT CALCULATING MACHINE CO., Oakland, California, U.S.A.-(Assignees of Friden, C. M. F.; 1056, Clarendon Crescent, Oakland, California, U.S.A.) Sept. 24, 1930, No. 28592. Convention date, Sept. 25, 1929. Void [Published under Sect. 91 of the Acts]. [Class 106 (i).] Multiplying and dividing apparatus.-A machine adapted to perform problems involving a plurality of computations at one and the same time comprises two calculating mechanisms one of which is provided with control devices the effect of which can be varied to control the operation of the other mechanism. In the form shown the machine comprises two sections A, B, Fig. 1, one of which is a complete calculating machine with a keyboard and all the various automatic and manual control devices and the other is a machine with a keyboard and a reverse control lever, the totalizer carriages being connected to move in unison. With this arrangement problems of the general formula X c may be evaluated by setting the dividend a on the totalizer of section A, the divisor b on the keyboard of section A, the multiplicand c on the keyboard of section B,. and by reversing the direction of movement of the actuators of section B with respect to those of section A. The machines shown are of the reversible rotary actuator type with keyboard mechanism and control devices as described in machines of the Friden type. The machine is driven by a pair of electric motors 1 aligned on a shaft 2, Fig. 2, and connected thereto through flexible couplings 3. The shaft 2 is geared through a friction coupling 7 to a driving shaft 10 on which one member of the usual ratchet- and-pawl clutch 12 is mounted. The clutch 12 is controlled in the usual manner by a bell crank 31, Fig. 3, a pin 36 on which co-operates with a notch in a link 37 pivoted to a control plate rockable anticlockwise by depression of the usual " + " or " - " keybars 101, 108. The clutch housing has fixed thereto a sleeve 51, Fig. 9, on which is journalled a pair of pinions 52, 53 one or other of which is adapted to be engaged by a pin 54 on a shiftable shaft 55 so as to drive the totalizer actuators in one direction or the other through the gear trains' 52, 15, 16, 17 or 53, 18, 15, 16, 17. The intermediate gear 16 also meshes with a gear 19 on a shaft 21 connected by gears 22, 23 to the driving shaft 24 of the actuators of section B. The shifting of the shaft 55 to reverse the direction of the drive is effected by a resilient coupling 56, 57, 58 on the shaft and a forked' arm 59 fixed to a shaft 60 having a notch engaged by a sector cam 61 pivotally connected to a link 112, the link being operated by a bell crank 111 when the " - " bar is depressed. The shaft 55 is movable independently of the arm 59 by a bell crank 358, Fig. 9, operative during an automatic division process in a known manner. The shaft 24 of the section B terminates in a sleeve 64, Fig. 10, upon which is journalled pinions 62, 63 selectively coupled by a train of gears with the set. of actuators 65 to drive them in one or other direction. The coupling is effected by a shaft 68 and pin 67 disposed in slots in the sleeve 64 and movable to engage a notched flange on one or other of the pinions by an arm 71 fixed to a shaft 69 longitudinally displaceable by the bent end of a manipulative lever 70. The sets of differential actuators 20, 65, the keyboard and differential setting mechanism, the item indicators, the totalizing-counter mechanism, the carriage-shifting mechanism, and the revolutions or quotients-counting mechanism, are well known in the type of apparatus referred to. The clearing mechanism of the two totalizers is also of the well-known type and is controlled selectively by laterally movable finger-pieces 276, Fig. 11, secured by pin-andslot connections to the ends of the totalizer shafts 172. An automatic division operation is performed in section A in the known manner. The mechanism described differs in this respect that the division lever 326, Fig. 12, is connected to a main division slide 328 and a supplementary slide 329 by pin-and-slot connections so arranged that the movement of the lever is communicated to the supplementary slide in both directions of movement but as regards the main slide this will be pushed to the rear on the forward movement of the lever but will not be returned on the lever being restored. The main slide is latched in its rear positions by a pair of pawls 333, 334. A pin 339 at the rear of the main slide co-operates in the usual manner with the reversing link 112 and with a bar controlling the clutch plate 38 so that when the division lever is pulled forward the process of division is initiated. When an overdraft registration occurs the known form of overdraft control mechanism, Fig. 13, functions depressing a link 357 to operate the bell crank 358, Fig. 9, and carry the pin 54 into engagement with the additive gear 52. Disengagement of the main clutch at the end of the additive operation is effected under the control of a lever 363 pivoted at 364 for movement in two directions. When the main slide 328 is displaced a sliding link 366 is moved to cause an arm 367 thereon to rotate the lever 363 and its pivot 364 into operative relation with respect to a cam on the actuator shaft. When this cam meets the lever 363 the lever is rocked on its pivot to lift the end of a lever 374, Fig. 9, of a double lever system the other end 376 of which is thereby raised to free the clutch control lever 31. At the end of the additive movement the known form of shift clutch 210, Fig. 11, is operated through the usual slide 381, Fig. 12, to effect the movement of the carriage after which the main clutch is operated to start the machine by means of a cam 216 rocking a shaft 393 having an arm 394, Fig. 3, co-operating with a pin 35 on the control lever 31. A known form of mechanism comprising a lever 398, link 397, and lever 395, Fig. 11, is provided to arrest the machine when the carriage reaches its home position ; the nose of the lever 398 enters an aperture in the base of the carriage track and frees the latches 333, 334. Manually controlled means are also provided for terminating a calculation prior to its completion. For this purpose the division lever 326 is returned to inoperative position and a cam face 404 on the supplementary slide 329 frees the latch 333. The second latch 334 is tripped at the end of the particular series of operations by the control link 37 rocking a lever 406, Fig. 19, overlying the latch. A special key 407, Fig. 27, may be operated in conjunction with the division lever to stop the operation at the end of any cycle, a pin 411 on a bar 410 operated on depression of the key being utilized to rock a bell crank 412, Fig. 12, co-operating with the latch 334. Means is described for controlling the circuit of the driving motor when one of the several machine controls is functioning. This mechanism includes normally open switches 476 operated by a rock shaft 482, Fig. 3, controlled by the main clutch centralizing lever 31a, Fig. 5. In division operations the contacts are held closed by the rocking of a shaft 491, Fig. 28, operating a lever 485. This shaft is rocked independently by other arms associated with the clutch members through pin- andslot connections so as to maintain the circuit. The arm 490 rocked by the shaft co-operates with an arm 497 on the end of the shaft 482 to block movement of the shaft when the arm is depressed thereby providing an interlock between the main actuator clutch and the clear and shift clutches. A " clear " key 526 is provided for clearing the keyboard of each section the depression of which rocks a bell crank 529, Fig. 22, and through a link 530 and universal bail 527 displaces the key latch slides 133. In adding operations the bail 527 is operated automatically at the end of each operation by means under control of the " add key 531, Fig. 23. This key when depressed rocks a lever 534 the rear end of which raises a pitman 532 into operative relation with the bail 527, the pitman being reciprocated by the main actuator shaft. Upon engagement of the main clutch in multiplying and division operations the depressed keys and the actuators are locked. The control plate 38 carries a link 540 co-operating with an arm 543 on a shaft 544 on the other end of which is an arm supporting a link engaging the locking arms that coact with the notched sectors on the actuators. The control plate 38 also carries a spring link 550 the forward end of which engages a pin on a lock bar 553 movable into position to engage depending lugs on the latch slides 133 to prevent release of the keys. These locks are disabled during adding operations by operation of the " add " key. A pin 560 lowers the forward end of the link 550 to free it from the lock bar and raises the rear end of the lever 534 clear of its connection 542 on the arm 543. In an example of use of the apparatus two successive multiplications may be performed concurrently provided one factor is of character readily reducible to its reciprocal. Multiplication involving a multidigit multiplier may be performed by setting the multiplier in the totalizer of section A and the multiplicand on the keyboard of section B and performing a division operation on the multiplier using " one " as the divisor.