Patent GB-704536-A (GB)
Title: Improvements in computing machines
IPC: G06C7/08
Filed: 1950-07-26
Abstract: 704,536. Calculating-apparatus; transfer mechanism ; zeroizing mechanism. BORG CORPORATION W. N. July 26, 1950 [Aug. 18, 1949], No. 18707/50. Class 106 (1) A computing machine for adding and subtracting calculations comprising a bank of coaxially arranged totalizer wheels, a gear for each of said wheels operatively connected thereto, an actuator for each gear having opposed rack portions on opposite sides of its respective gear spaced by a distance greater than the maximum diameter of said gear, operator-controlled means for reciprocating said actuators lengthwise of said rack portions by predetermined amounts, and means for moving said actuators selectively to bring either of said rack portions of each actuator into mesh with its respective gear or both rack portions out of mesh preparatory to such lengthwise motion in one direction is characterized in that said actuator-moving means comprise a shaft operatively associated with said actuators and mounted for movement transverse to the length of the racks, an oscillatory cam carried by said shaft and positioned between fixed abutments to move said actuators into adding engagement with their respective gears upon being swung in one direction and to move them into subtracting engagement with their respective gears upon being swung in the other direction, means engageable and movable by an operator-controlled reciprocable under-carriage to swing the said cam in one direction or the other, and said cam swinging means being constructed and arranged to engage selectively members supported on opposed portions of said cam to swing the cam in one direction or the other direction as desired. Keyboard and pin carriage.-The machine comprises ten digit keys 3-12, Fig. 1, the stems 15 of which extend through the casing 1, Fig. 3, and a transverse partition 16. The stems 15 have arms 17, Figs. 19 and 20, which extend over one or other of two plates 18 hinged at 22. The extremities of the arms 17 of the keys corresponding to the digits 0-8 are aligned at 25, Fig. 20, in an opening in the plates 18, the remaining arm being stopped above the adjacent plate 18. The extremities 25 of the arms 17 lie above a selector pin carriage 40, Figs. 3 and 5, transversely movable on a rod 41. Each pin 35 in the carriage 40 is vertically movable between two positions in each of which it is yieldingly retained by a spring, Fig. 21 (not shown). Carriage driving means and escapement.-A ribbon spring 50, Figs. 5 and 23, is attached at one end to the carriage 40 and at the other end to a segment 51 carried by a shaft 52, Fig. 5, which has a pinion 53 which meshes with a rack 54 carried by a slide plate 55. A spring 56, Fig. 23, attached to the slide 55 and to one end of a transverse lever 58 the other end of which is pivoted at 59 urges the slide 55 forwardly. A roller 580 carried by the lever 58 runs along a partition 217, Fig. 23. The shaft 52 and a pin 62 secured to the lever 58 pass through parallel slots 60, 61 respectively in the slide 55. A roller 65 carried by a fixed member 66 retains the ribbon spring 50 against the segment 51. The springs 50, 56 urge the carriage to the left and their driving pulls are complementary so that the driving force on the carriage is constant. The carriage has a front flange 70, Fig. 5, having a series of notches and teeth 71, 72, Figs. 19, 20, respectively, with which a pair of hooks 78, 81 of interconnected dogs 77, 79 co-operate. When a plate 18 is depressed by depression of a key the hook 81 leaves the first notch 71 and the hook 78 comes in front of the first tooth 72. Upon return of the plate 18 a spring 85 moves the hook 81 into the second notch 71 and the hook 78 is raised. Successive depressions of any key will thus result in the carriage being moved stepwise. Accidental movement of the carriage to the right is prevented by a spring pressed dog 95, Fig. 19, which has a hook 96 which projects into one of the notches 71. The dog 95 is moved upwards by a spring when the totalizer actuating mechanism is operative. Totalizer.-The totalizer comprises a series of numeral wheels 120, Figs. 5 and 13, carrying two series of numerals from "0" to "9" visible serially through a window 125 in the casing 1, Figs. 1, 13. Each wheel 120 comprises a pair of discs 126, 127, Fig. 17, secured to the hub of a pinion 130 which is normally locked by a finger 140, Fig. 13, carried by rockable U- shaped frame 141. Each disc 127, Fig. 17, has two diametrically opposite projections 135. Differential-actuating mechanism.-The totalizer is actuated by a hand bar 150, Figs. 1, 3 and 13, carried by a pair of arms 105 which extend through slots 155 in the casing, are fulcrummed on a transverse bar 156 and are interconnected by a bail 157. The lower end of each arm is connected to a link 159, Fig. 3, to which is attached one end of a rod 160 which slidably extends through the flanges 161, 162 of a U- shaped member 163. A spring 164 coiled round the rod 160 is connected to the flange 161 and a flange 165 of the link 159. Each member 163 is connected by a pin and slot connection to an arm 170 pivoted on a trunnion 171 and connected to a link 173 pivoted at 174 to an adjacent slide member 175 of an under-carriage. The slide members 175, Fig. 27, are interconnected by a plate 178 which has a forward central extension 179 having a rack 180 which meshes with a pinion 181, Fig. 23, integral with a serrated wheel 183 with which a pair of pins 184 on an oscillator bar co-operates to limit the speed of rotation of the wheel 183 and also the speed of the moving parts. A bar 201 is mounted in slots 200, Fig. 27, in the slide members 175 and supports a series of longitudinal bars 201, Fig. 13, having slots 203, 204, 210, Fig. 27, for receiving the bar 201, a transverse rod 176, Fig. 13, and the bar 156 respectively. Each bar 202 is connected to the bar 201 by springs 206. Upon rocking movement of the bar 150 the under-carriage 175, 178, Fig. 27, is given a rearward movement through the above linkages and the bars 202 are urged rearwards by their springs. The bars 202 in decimal orders in which no selector pin is depressed are, however, each locked by a hook 220, Fig. 13, which is brought into engagement with a shoulder 226 on the bar. A flange 224 on the carriage blocks the other hooks 220 and each associated bar 202 moves rearwardly until a shoulder 227 thereon abuts the depressed selector pin. A flange 230 of the pin carriage acts as the stop for the " 9 " digit key. Adjacent each bar 202 and connected thereto by a spring 296 is an actuator 250 longitudinally slidable on guide rods 221, 253, Figs. 5, 13, and having upper and lower racks 255, 256. The guide rod 253 is vertically movable in slots 2531 in walls 216, 217, Fig. 5. Each end of the guide rod 253 is carried by a cam 260, Figs. 3, 7 and 10, supported between two pins 261, 262 on the adjacent wall 216 or 217 and having opposed high, low and intermediate portions 265, 266, 267 respectively. A member 270 positioned adjacent the wall 217 is pivoted on a pin 271 and has a slot 273 through which projects a pin 274 on an L-shaped member 275 fulcrummed on the pin 271. A spring 277 urges the member 275 counter-clockwise against a lug 279 of a lever 280 which is pivoted on the pin 271, projects through the casing and has an actuating knob 290. With the knob 290 in its intermediate "add" position the member 275 positions the member 270 so that a slot 312 therein engages a pin 314 on the cam 260. At the end of the above rearward movement of the undercarriage the cross bar 176 is moved rearwardly and a plate member 301 carried thereby moves, through a pin 310, Fig. 3, the member 270. The cams 260 are thereby rocked counter-clockwise and raised so that the bar 253 is lifted and the lower racks 256 of the actuators 250 mesh with the pinions 130. At the same time the member 301 rocks the frame 145, Fig. 13, so that the fingers 140 are removed from the pinions 130. As the hand bar 150 is released to return to its starting position the links 159, Figs. 3 and 5, are pulled forwardly and a pair of springs 325 pull the under-carriage 175, 179, Fig. 27, forwardly whereupon the bar 201 returns the bars 202 each of which through the spring 296, Fig. 13, returns the corresponding actuator 250 which enter the set number into the totalizer. At the end of the return motion the shaft 176 moves the member 301, Figs. 7 and 10, to return the member 270 which restores the cams 260, the bar 253 and the locking fingers 140 to their initial positions. This process is repeated for the number of additions required. For subtraction the minuend is first entered into the totalizer in the manner described, above The knob 290 is moved to its rear position, Fig. 1, in which the pin 313, Fig. 7, of the associated cam 260 engages the slot 311 of the member 270. and the subtrahend is entered into the pin carriage. The hand bar 150 is depressed and the under-carriage 175, 178, Fig. 3, moves rearwardly as described above. The member 270 rocks the cam 260 clockwise to lower the bar 253, Fig. 13, and the racks 255 of the actuators 250 are brought into engagement with the pinions 130 so that upon return of the bar 150 the number in the pin carriage is subtracted from the number in the totalizer. This process is repeated for the number of cycles required. Transfer mechanism.-When a numeral wheel 120 is moving from "9" to " 0 " an ear 135, Fig. 13, thereon rocks an arm 331 to free a hook 335 from a lug 337 projecting from the next higher actuator 250 which is moved by its spring 296 until a pin 295 thereon meets a shoulder 2990 of its associated bar 202. The arm 331 is maintained in either of its two positions by a leaf spring cam 341 which engages a pin 340 on the arm. When the bar 202 again moves rearwardly a lug 243 thereon returns the arm 331 and therefore the hook 335 to their initial positions. Modified transfer mechanism.-In a modified transfer mechani