Patent GB-411291-A (GB)
Abstract: 411,291. Calculating- apparatus. FAIRWEATHER, W. C., 66, Chancery Lane, London.-(Underwood Elliott Fisher Co. ; 342, Madison Avenue, New York, U.S.A.) June 8, 1933, No. 16440. [Class 106 (i).] In a combined typewriting and computing machine subtraction is effected by reverse rotation of the totalizer pinions for which purpose a set of idler gears is provided, the gears being constantly in mesh with the actuating racks and the totalizer pinions being selectively movable into direct engagement with the actuating racks for addition or into engagement with the idler gears for subtraction. Means are also described for effecting transfer and preventing overthrow in the totalizer. The invention is particularly applicable to the Underwood- Hanson type of computing machine. As shown in Figs. 1, and 2 the machine is provided with two totalizers each having its own set of differential actuating bars 41 with index pins 42 settable when the typewriter carriage 34 reaches a computing zone. In this position the carriage is tabulated to the appropriate denomination and a tappet 50 depresses a corresponding push rod 52 to rock a yoked bell crank 53 and displace a member 54 pivoted thereto so as to move the bar 41, by engaging a pin 55 thereon, to position its pins 42 in alignment with the setting bars 48 that are connected by linkages 47 to shafts 46, each adapted to be rocked by a stem 45 depending from a numeral key 30 to set the corresponding pin. Normally the zero pin 40 in each bar is projected but this pin is retracted on setting another digit pin. The set pins project into the path of fingers 58 formed on levers 59 carried by a universal cross-bar 60 reciprocated by the operating mechanism to impart differential movement to the bars 41. The cross-bar 60 is connected to plates formed with racks 65 coupled at each side of the machine through an intermediate pinion 70, to a sector 69 on the operating shaft 68 which may be hand operated. For operation by power the cross-bar is connected by a link 72 to a cam shaped head 73, co-operating with a roller 71 on a disc 77 adapted to be driven by a motor 61 through a one revolution clutch 80. On the return of the cross-bar it engages a projection 297 on a link 296, Figs. 5, and 16, having a resilient spring connection with a bell crank 290 constituting a restoring bail with prongs 294 for restoring the set pins 42 and resetting the zero pins through co-operating levers 286. The bail is freed at the end of the return movement by raising the rear end of the link through a rod 305 operated by a roller 308, entering a notch in the rack 65. Adding and subtracting apparatus.-The totalizer wheels 40 carry pinions 88 and are rotatably mounted on a spindle 91 mounted in a shiftable frame 92, Figs. 2, 4, and 5. The frame is movable about trunnions 103 to engage the pinions 88 directly with racks 89 formed on the actuating bars 41 for addition and is slidable rearwardly to engage the pinions 88 with idler gears 90 constantly in mesh with the racks 89 for subtraction. The frame 92 is mounted between fixed plates 96 in which are formed slots 102 for the trunnions 103 and L-shaped slots 315 for the ends of the spindle 91. The swinging of the frame downwardly for addition is effected by slotted arms 100 on a rock shaft 99 and the rearward movement for subtraction is effected by the engagement of the trunnions with slotted arms 105 on a rock shaft 104. Movement of the shaft 99 or of the shaft 104 is effected under the control of a subtraction key 134 that is connected to a control lever 123, Figs. 21, and 23, having arms with pin and slot connections 127, 128 to a link 119 and slide 111 respectively. In the normal or adding position shown in Fig. 21 the link 119, which is connected to an arm on the rock shaft 99, has the lower end of a slot 120 therein engaging a pin 121 on an arm 109 loose on the shaft 104 so that when the arm 109 is rocked by the rotation of a cam 108 the shaft 99 is rocked. For subtraction the key 134 is pushed in and held by a latch device 151 ; this operation displaces the control lever 123 to the position shown in Fig. 23 to free the pin 121 from the lower end of the slot of the link 119 and at the same time moves the slide 111 that is mounted on the arm 109 to cause its tongue 117 to engage a notch in an arm 115 secured to the rock shaft 104 thereby rendering the shaft 104 operative to shift the totalizer pinions into engagement with the idler gears when the arm 109 is rocked. In this latter position of the control lever its pivot stud 125 is effective to lock the link 119 against movement by engaging a notch 130 therein. During the to and fro movement of the main cross-bar 60 the cam 108 is given a complete rotation through the agency of a double clutch device 155 mounted on the end of the cam shaft 133. The device comprises discs 165, Fig. 18, keyed to the shaft and carrying oppositely disposed spring-controlled pins 164 projecting into grooves on the inner faces of gear sectors 158, 159, loose on the shaft 133, the grooves being formed with single clutch teeth 163 for engagement by the pins. In the forward movement of the cross-bar the rack 65 drives a pinion 160, Fig. 19, to rotate the sector 158 idly while another sector 156 on the shaft 68 engages the sector 159 directly to rotate the shaft 133 clockwise. On the return movement of the cross-bar the rack 65 drives the sector 58 which is then effective to continue the clockwise movement of the shaft. During the forward movement of the cross-bar the totalizer pinions are first engaged with the racks 89 or idler gears 90 and the fingers 58 on the levers 59 pick up the set index pins and thereafter the actuating bars 41 are moved until the pins contact with the stops 179 on the end of stop bars 181 thus imparting their movement to the totalizer pinions in one or other direction. The stops 179 are normally spaced from the zero index pins to allow for the displacement of the bars during a setting of the index pins. The bars 181 co-operate with a latch bar 183 and the latch bar is movable under the action of a forked lever 215 and cam 213 on the sector 156, the lever causing a shaft 212 to rock and through arms 218 and connecting links 219 attached to the latch bar effects a movement of the bars 181 rearwardly to set the stops 179 to arrest the actuating bars at the position normally occupied by the zero index pin. Transfer mechanism.-Carry-over is effected by allowing an additional step movement to the bar 41 of next higher denomination. For this purpose a tooth 200 on a totalizer wheel, at the instant of transfer, rocks a lever 201 to free a notch 184 on the stop bar 181 of next higher denomination from the latch bar 183 whereupon under spring action the stop bar moves forwardly being pivoted to a lever 185 mounted on an axis 186. This counter-clockwise movement of the lever 185 sets a pin 190 thereon into the path of movement of the projection 191 on the lever 59 and as the projection encounters the pin the lever 59 will be rocked to advance the bar 41 an additional step through its contact with the set index pin. The position of the stop bars 181 when no transfer takes place is shown in Fig. 6 whilst in Fig. 7 the parts are shown after a transfer is effected. In most cases the levers 59 will be rocked positively by the action of the cross-bar and the release of the stop bars setting the pins 190. In those instances where transfer occurs after the actuating bars 41 have reached their forward position the rocking of the levers 59 will be effected by the power afforded by the springs 182, 193. Aligning and locking mechanism.-A plate 238, Figs. 1, 5, and 6 mounted on a rocker bar 239 is formed with detent prongs 237 for aligning the totalizer pinions 88 in their disengaged position. The prongs remain stationary as the pinions are moved into engagement with the actuating racks but on the sliding movement of the totalizer frame to engage the pinions with the idler gears the plate 238 is rocked to raise the detents by means of its end projections 241 cooperating with cam surfaces 245 on the frame plates 96. Associated with each set of idler gears is a detent bar 235, Figs. 10, and 11, mounted on side arms 247 pivoted to the plates 96 and movable into and out of engagement under the control of a cam 252 on the shaft 133 and a latch 253 on an arm 262 controlled by a slotted link 264 and spring 260, the spring being attached at one end to the link and at the other end to an arm 263 on the rock shaft 212. The action of the cam is such that the detent bar 235 is withdrawn before the pinions 88, in mesh with the rack 89 or idler gears 90, begin to rotate. Rotation of the shaft then places the latch 253 under the end of the side arm 247. The release of the latches 253 at the end of the transfer interval after the cross-bar 60 has completed its forward movement is effected under the control of the clutch roller 70 which cooperates with an arm 272 operatively connected by an arm 271 and link 270, to the latch arm 262. The cam shaft 133 is aligned at each half revolution position by means of a detent arm 282 engaging a notched disc 281, Fig. 5, on the shaft. In a modified construction four registers are provided and the cross-bar racks are operated by a reciprocating member driven by a crank arm associated with a known form of clutch and motor drive. The operating mechanism is such that the last portion of the forward stroke of the driving member and the first part of the return stroke are ineffective to move the cross-bar in order to afford time for the carrying or transfer operations.