Patent GB-305540-A (GB)
Abstract: 305,540. Friden, C. M. F. Feb. 6, 1928, [Convention date]. Multiplying and dividing apparatus.-In a powerdriven machine with a reversible rotary actuator for performing calculations according to the four rules, such as described in Specification 229,642 means are provided for automatically controlling the operation of the machine in performing division. The means operates on the occasion of an overdraft registration in the numeral wheels to correct the over. draft by giving the actuator a turn in the additive direction, stop the actuator and shift the totalizer carriage to the next denorninational position, start the actuator again in the subtractive direction until an overdraft occurs, and repeat the process until the carriage reaches its limit position. Several parts of the mechanism described are similar to those described in Specification 283,137, thus, for example the operation keys 51, 61, Figs. 1,2, and 8, co-operate with the clutch lever 18 through a notched control bar 71 to permit engagement of the usual clutch members, the direction of rotation of the actuator is controlled by reversing gears 24, 25, Fig. 10, which can be coupled to the clutch by means of a slidable pin 27 adapted to engage one or other of the interrupted flanges on the gears, the manual shifting of the pin 27 is effected through the usual shifting rod 43 by means of a notch engaging a sector-shaped cam 57, operatively connected by a link 55 with the bell crank 52 co-operating with the negative operation key 51, and the revolutions or quotients counter 75 is actuated by a single toothed member 78 splined to a shaft 79 and movable under the control of the totalizer carriage. In the machine shown the pin 27 is secured to a rod 28 having a collar 38 enclosed in a housing 39 with a spring 41 and so arranged that movement of the housing produces a movement of the rod while permitting a movement of the rod without affecting the housing. The transfer mechanism for the counter 75 comprises the usual drum 81 and staggered pins 82, 83 and the direction of rotation of the drum may be reversed with respect to that of the actuator by a reversing gear similar to that mentioned above comprising pinions 85, 86 and a transversely movable pin 87 secured to a rod 88 within the hollow drum shaft 84. A pinion 91 on the shaft through gearing 92, 93 drives the shaft of the actuating member 78 in the same direction as that of the drum shaft. The machine is adjusted for performing division by movement of a setting lever 96, Fig. 3, to its forward position whereupon a bar 98 pivoted thereto, through a pin working in a slot 102, rocks a lever 99, Fig. 6, having sector-cam portions 105, 106 serving to control the longitudinal position of the rod 88 and that of the bar 123 associated with the reversing and stopping means. At the same time a stud 108 on the bar 98 operates the link 55 to set the shifting rod 43 to cause reverse rotation of the actuator. The bar 123 has a downturned end engaging a slot in a shiftable arm 119 mounted on a lever 116, Figs. 14 and 16, pivoted on a stud 115 and held in contact with the rear face of the transfer lever 6 by means of a spring 118. In division when the numeral wheel of the next tc the highest order shows " 9 " the transfer lever is rocked and the arm 119, which has been set by the bar 123 to overlie the foot 138 of a lever 137 pivoted to a lever 125, rocks the lever 137 so as to project a spring-controlled pin 134 mounted on the lever 125 into the path of a cam 135 secured to the actuator shaft. The lever 125 has pivoted thereto a: link 126 the lower end of which bears upon the arm 127 of a bell crank lever so that when the cam meets the projected pin just before the actuator reaches full cycle position the link 126 depresses the arm 127 and causes the other arm 129 of the bell crank to shift the rod 28 through engagement with a collar 131 thereon to reverse the direction of rotation. To disengage the clutch and stop the actuator at the end of the additive rotation the arm 127 in its downward movement rocks a lever 142 pivoted on a shaft 141 and through its engagement with a pair of interconnected levers 145, 147, raises the clutch control bar 71 to free the clutch lever 18. The connection between the lever 147 and bar 71 is effected by means of a tongue 148 on the lever 147 disposed in an aperture 149 in the bar. The negative operation key 51 is held in depressed position during the division operation by means of a spring-controlled latch 232. Fig. 2, engaging a notch in the key stem and the posi. tive operation key 61 is maintained in its raised position by the engagement of the bell crank 52, Fig. 8. with a lever 152 co-operating with the roller 66 on the key frame 67. The totalizer carriage is slidable transversely by means of shifting mechanism similar to that described in Specification 212,207 comprising a slide with operating pawls and a stud 195, Fig. 11, engaging a slotted arm 193 secured to a shaft 192 extending to the front of the machine. The arm 193 also carries a stud 196 engaging a notch in a reciprocable link 197 co-operating with a cam disc 199 secured to a clutch housing 201 loose on a shaft 202. The shaft 202 is geared to the main shaft 9 and has a ratchet wheel 212, Fig. 7, forming with a pawl 213 on the housing 201 the clutch members. At the end of the additive rotation, i.e. a counter clockwise movement of the drum 81, a pin 221, Fig. 3, thereon engages a spring-controlled slide 223 and forces the lower end of the slide against a pin 222 on an arm 217 rocking a shaft 216 so as to cause a movement of the control lever 214 to effect engagement of the clutch. This automatic carriageshifting mechanism is rendered inoperative during addition, subtraction, and multiplication operations by means of a projection 229, Fig. 3, on the link 98 attached to the setting lever 96 engaging a saddle plate 235 supporting a pin 284 on the slide 223 to move the slide so that the pin 222 on the arm 217 lies outside its path of movement. After the carriage has been shifted, the main clutch is re-engaged by means of a cam 241 on the clutch shaft 202 rocking a lever 242, Fig. 6, secured to a shaft 244 whereby a finger 245, Fig. 2, thereon engages beneath a pin 246 on the control lever 18 to establish the driving connection. The operation of the machine is terminated when the carriage reaches its limit position by means which is effective to release the negative operation key 51 and to displace the slide 223 to inactive position. For this purpose the carriage trackway 179, Fig. 12, has an aperture 248 normally covered by the carriage and into which projects a spring-controlled trigger 249 normally held by a latch 252 co-operating with a bracket 253. The latch has a pin 255 overlying the clutch tripping lever 147 so that when the lever is operated the latch is released and re-engaged unless the aperture is uncovered whereupon the trigger is rocked and a pin 265 thereon rocks an arm 258 and through a parallel arm 259 and connecting link 262 causes the link to disengage the operation key latch 232 by engaging its finger 268 and to raise the saddle plate attached to the link thereby swinging the slida 223 to inoperative position. Operating by motor. - The control switch in the motor circuit is normally open and is closed by the depression of any of the operating keys. In division operations the switch is closed by the key 51 and remains closed until the key is released. The control switch is associated with the clutch control lever 18 and comprises contacts 284, 285 on metallic elements 278, 279, Figs. 2 and 18, spaced apart by a block of suitable insulating material 281 mounted on a shaft 283 to which is secured an arm 287. Movement of the control lever 18 to free the housing 13 rocks an arm 290 engaging a lateral projection 289a on an arm 289 and through a shouldered link 288 engaging the arm 287 rocks the shaft 283 to close the switch contacts by flexure of the members 278, 279. The switch is maintained closed during the time the actuator is out of full cycle position by means of the centralizing lever 292, Fig. 5, being moved into contact with the projection 289<a> of the arm 289. In division operations during the time the carriage is being shifted and the main driving clutch is disengaged the control switch is held closed by means of a cam 307 on the shaft 202 engaging a shoe 306 on an arm 305 of a rock shaft 304 another arm 303 of which bears on a foot 302 of a lever 299 having an eyelet 301 engaging a projecting pin 297 on the shaft 283. Specification 212,206 also is referred to.