434,436. Typewriters &c. BRITISH TABULATING MACHINE CO., Ltd., Victoria House, Vernon Place, Southampton Row, London. March 2, 1934, No. 6758. Convention date, March 3, 1933. [Class 100 (iv)] [See also Group XIX] Platen and feed-roller rotation for blanking; line-spacing mechanism paper supports.-Mechanism employed in a statistical or like machine for feeding a strip consisting of a series of sheets of equal length comprises an intermediate member for rotating the platen or feed-rollers to effect blanking, and an operating-member which has a constant stroke and is so connected to the intermediate member that the velocity ratio decreases in proportion to the number of previous line-spacing operations, the operating and intermediate members being moved with gradual acceleration and retardation to effect blanking-feed smoothly and without slip. The mechanism may be embodied in a record-card controlled machine, provision being made, as described below, for initiating blanking-feed at the end of a sheet, or after the printing of a major or minor total. Provision may also be made for preventing card-feeding during blanking-feed, and for preventing blanking-feed unless cards are in the machine. The platen or feed-roller may be mounted on a support which can be swung upwards to facilitate threading of the strip. Means comprising gears and a one-way clutch are operated, when the platen is swung, to impart to the strip a blanking- feed equal to the head-space on a sheet. The carriage 56, Fig. 4, supports a platen 51 and a strip-roll 72, the strip being led over a shelf 74 around the platen, and beneath feed-rollers 75. To facilitate threading of the strip, the platen can be swung upwards and counterclockwise, and for this purpose the platen shaft 69 is mounted in brackets 61 secured to a bar 60 trunnioned in the ends 58 of the carriage, one of the brackets being provided with a knob, and being associated with a detent for holding the platen in normal or raised position. The arc of swing of the platen extends through an angle of 220‹, mechanism, described below, for headspacing the strip being operated during the return swing. The shelf 74 is secured to plates 77 which are mounted on the platen shaft and rocking arms 79, the arrangement causing the shelf to remain tangential to the platen when the platen is swung. The feedrollers 75 are mounted on a shaft 82 which is geared to the platen shaft and is supported in yokes 84 which are fulcrumed on the bar 60 and engage bow-springs 86. The feedrollers can be released by means of a fingerpiece on a rock-shaft 92 which is mounted in a groove in the bar 60 and is formed with a flat engaging lugs 91 on the yokes 84. The carriage can be locked in different column positions by means of a manually-operated catch. Automatic blanking and line-spacing mechanisms are mounted as a unit in and on a casing 134 which is secured to the carriageend 58 and supports a platen-rotating motor CM. A pinion 107, Figs. 4 and 15, forming part of the mechanism is geared through an idler 108, mounted on one of trunnions 59 of the bar 60, to a pinion 109 formed on a clutchplate 110 co-operating with a clutch-plate 111 on the platen shaft 69. A detent 113 carried by a lever 114 co-operates with a star-wheel 112 to hold the platen in set position. The pinion 107 is secured to a shaft 176 provided with a ratchet-wheel 179 co-operating with a line-spacing pawl 177, Fig. 8, on a rocking plate 175 which is connected to a link 172 having a pin 173 in the path of a bell-crank 168 co-operating with a loose cam 154 on a shaft 151. A pawl 155 on the cam is normally held out of engagement with a continuously rotating ratchet-wheel 152 by means of a finger 160 on the armature 161 of a line-spacing magnet LSM. On energization of the magnet, the cam makes a revolution, and the ratchet-wheel 179 and pinion 107 are stepped on, the movement being transmitted by the clutch 110, 111 to the platen. To adjust for single, double, or treble line-spacing, the link 172 is adjusted to bring the pin 173 into register with a corresponding notch 171 in the bellcrank. The link is adjusted by means of a rock-arm 183 connected to a fingerpiece 180 provided with a detent 181. The line-spacing pawl is normally disengaged from the ratchet-wheel, backward movement being prevented by co-operation of a star-wheel 190 with a detent 191. The blanking mechanism comprises a rocking sector or intermediate member 220, Figs. 13 and 15, which engages a pinion 222 on the shaft 176 and is connected by a link 217 to a rocking operating-member 213 which is connected by a link 210 to a loose cam-disc 200 on a shaft 170. The sector is provided with a returning-spring 242. The pinion 222 can be disconnected, to disable the blanking- mechanism, by pulling outwards a knob 232. A pawl 198 on the cam disc is normally held out of engagement with continuously rotating ratchetwheel 197 by means of a finger 201 on the armature 203 of a blanking-magnet EM. The member 213 is pivoted at 241 and is formed with an arcuate slot receiving a slide 215 which is pivoted to the link 217 and is formed with a tooth for engaging teeth 214 in the slot. When the magnet EM is energized, the cam-disc 200 makes a revolution, and the member 213 is moved forwards and backwards through an angle of 90‹, each movement being gradually accelerated and retarded. The forward movement causes the platen to rotate for blanking, the gradual acceleration and retardation causing the strip to be fed smoothly and without slip. Operation of the line-spacing mechanism is prevented when the sector is in forward position by means of a link 425, Fig. 8, which is displaced by the sector and obstructs the armature 160. During linespacing operations, the sector is stepped forwards by means of the pinion 222, and the link 217 draws the slide 215 down the member 213, and when the member rocks forwards, the movement imparted to the sector, and consequently the blanking-movement of the platen, are reduced in correspondence with the number of previous line-spacing operations. When the member 213 is in forward position, the slot therein is concentric with the pivot 246 of the link 217, the arrangement causing the sector 220 to move into the same ward position irrespective of the position of the block 215. During blanking-operations, the detent 113 is released by means of an arm 307, Fig. 4, connected to an arm 305, Fig. 13, arranged in the path of a boss 1304 on the link 210. When the member 213 is rocked backwards, the slide 215 is released from the teeth 214 by means of a releasing-plate 247, and is returned to initial position by means of the link 217. The releasing-plate has pin-and-slot mounting 248 on the member 213 and is formed with a slot 249 engaging the slide. During backwards rocking of the member 213, the releasing- plate is displaced by co-operation of a lug 250 with a dog 251, and the slide is released, the releasing-plate being retained by a latch 254. To determine the length of the forms, the initial position of the sector 220 is adjusted by means of a stop-lever 259, Fig. 10, which co-operates with a stop 260 on the sector and is provided with a catch 265 for engaging notches formed at linespace intervals in a segmental scale-plate 261. The above-described mechanism may be embodied in the statistical machine described in Specifications 247,200, [Class 100 (iv)], and 299,014, [Class 106 (i)], the circuits of the machine being modified to include the circuits shown in Fig. 32, and comprising magnets MA, MI, in circuit with the major and minor group-control magnets, and switches for controlling the manner of operation of the machine. During initial movement of the cam-disc 200, a lever 278 depresses a link 281, and an arm 285 connected thereto opens contacts 286. There- ' upon, a relay CMR is de-energized, contacts 362, 360 are closed and opened to cut out a resistance R for the motor CM, and the power of the motor is increased to effect blanking. Moreover, contacts 361 in circuit with the tabulating-motor relay are opened to delay tabulating-operations until blanking has been completed, and an arm 194 is rocked to release the detent 191 and thereby free the shaft 176. Towards the end of the blanking movement, a projection 290 on the cam-disc moves further the lever 278, and an arm 299 connected thereto opens contacts 292, thereby preventing blanking-feed unless record-cards are in the tabulating-machine. The arm 299 is connected by a link 296 to an arm 295 having a pin 294 in the path of the tail of the lever 278. The arm 295 is normally latched by means of the armature 304 of a magnet LCLM which is energized only when record-cards are present under the lower reading-brushes of the tabulating-machine. When the projection 290 moves the lever 278 into extreme position, contacts 291 for re-establishing the tabulating-motor circuit are closed. The circuit is normally re-established towards the end of a total printing cycle by cam-contacts. If, however, such cycle is followed by a blanking- operation initiated during the cycle, or a blanking-operation is initiated but no totals are printed, the circuit is re-established by the contacts 291. When the machine is set for listing, a switch 374 is closed to prepare a circuit for the magnet LSM, the strip being linespaced each time the magnet is energized, and the spacing being adjusted by means of the finger-piece 180. To set the machine for printing major and minor totals on the same line with double line-spacing between the lines of totals, the finger-piece 180 is set, the switch 374 is opened, and circuits under control of the magnets MA, MI, and including camcontacts P<12>, P<13> are prepared for the magnet LSM. If a minor total is printed, the circuit includes contacts 377, whilst if a major total is printed, contacts 377, 382 are open during printing of the minor total. There