501,734. Cash registers. NATIONAL CASH REGISTER CO. J'uly 27, 1937, Nos. 20701 and 20702. Convention dates, July 27, 1936 and Nov. 25, 1936. [Class 100 (iv)] [Also in Group XIX] Printing-mechanism for a cash register or similar accounting machine includes means automatically to feed record material backwardly and forwardly at each operation, the extent of the backward and forward feeds varying in different kinds of machine operation to give the required line-spacing. The invention is described as applied to a machine of the Shipley type disclosed in Specification 8119/15, [Class 106 (i)], and many other Specifications, and in particular to a machine of this type having record-strip printing and control means forming the subject-matter of Specification 490,524. The machine is now provided with means for printing a single-item or the total of a multiple-item transaction in duplicate on an inserted slip, Fig. 37, and, in the absence of a slip, for printing and issuing a single-item stub voucher, Fig. 12, or a multiple-item stub voucher, Fig. 36. In all operations in which a voucher is printed, the voucher strip is fed backwards and forwards by feed rollers and/or an electro-roller to space the data and position the voucher for perforation and severing. Voucherissue is controlled by a manually-set lever 515, Fig. 3, having three positions : " Off," " Automatic " and " On." In the " Off " position of the lever, voucher-issuing is suppressed. In the " Automatic " position, voucher-issuing is suppressed in certain types of transaction under the control of the keys of the transaction bank. In the " On " position, a voucher is issued irrespective of the type of transaction. No voucher is issued when a total or subtotal is taken from a clerk's or transaction totalizer. In multiple-item transactions, the number of items entered is indicated by numerals on a drum 402 visible through an aperture in the keyboard. The keyboard, Fig. 3, is similar to that described in Specification 490,524 and comprises amount keys 144, clerk's keys 204 transaction keys 205 . . . 209, 215, operation control lever 123 and motor bar 68. The transaction bank includes three stay down multiple-item keys 205... 207, four singleitem keys 208, a " No Sale" key 209 and a key 215 for releasing any erroneously depressed key in the bank. In item-entering operations, machine-release is prevented until amount and clerk's keys have been depressed. In ordinary total-taking operations, this condition is removed. The machine is provided with mechanisms for printing on a record strip, an issued voucher and an inserted slip, the two latter mechanisms only being described herein. A voucher or slip are printed alternatively, in dependence upon the absence or presence of a slip, from a single set of typewheels on a shaft 198, Fig. 11, the voucher strip being impressed by an upper hammer 464 and the inserted slip by a lower hammer 874. A reversible ink ribbon carried by a removable frame 629 co-operates with both hammers. The printing-mechanism is driven by a shaft 101, Fig. 43, that makes one counterclockwise revolution in each operation, being declutched from the main drive shaft in the first cycle of total and subtotal taking operations by the means described in Specification 490,524. The drive shaft 835, Fig. 11, for the slip printer is permanently geared to the shaft 101 and likewise makes one counterclockwise revolution in each machine operation. The drive shaft 501 for the voucher printer is connected to the shaft 101 through the clutch mechanism shown in Fig. 43, and is adapted to be disconnected therefrom to disable voucher printing and issue by the clockwise movement of a pawl 758 controlled by the hand lever 515, Fig. 3, the transaction differential, the total control lever and the slip feeler, as hereinfter described. Part of the voucher printing and feed mechanism is operated by cams on a sleeve rotatahle on the shaft 501 and normally coupled thereto by the clutch mechanism, but adapted to be uncoupled and locked in multiple-item entering operations. Hammer. - impression arrangements.-The hammer 464, Figs. 11 and 14, for impressing the voucher, Figs. 12 and 36, is pivotally supported on arms 632 connected through a link 633 to a cam-follower 636, Fig. 15. In single-item and multiple-item total operations, the hammer makes two imprints, being actuated by a cam 603 fast on the sleeve of shaft 501 and provided with two lobes. In multiple-item entering operations, the hammer is actuated by a cam 679 on the shaft 5011. and makes a single imprint, Fig. 36. The date, consecutive number and machine number are not printed in multiple-item entering operations, the part of the platen 627 that overlies these type-wheels being raised relatively to the remainder of the platen. For this purpose, the adjustable part of the platen is slidable vertically in the hammer and positioned relatively thereto by a lever 669 pivoted on the hammer and connected, through the linkage shown, to a shaft 355, that is rocked in multiple-item entering operations. The hammer 874, Figs. 11 and 44A, for impressing the inserted slip, Fig. 37, is pivotally supported on a shaft 836 and makes two operative strokes in every machine operation in which a slip is present. For this purpose, a cam 876, on the shaft 835 that makes one revolution each machine operation, actuates a lever 879 normally connected to the hammer by an arm 881 that is pivoted to the lever and carries a stud 882 embraced by a slot in the hammer. However, in an operation in which a slip is not inserted, an arm 885 of a shaft 841 controlled by the slip feeler is rocked counterclockwise and, by means of a cam-slotted link, rocks the arm 881 counterclockwise to cripple the hammer drive. Sheet and web feeding arrangements ; line spacing mechanism.-In all single-item operations in which the voucher mechanism is enabled, a voucher similar to that shown in Fig. 12 is printed and issued. At the beginning of the operation, the leading edge of the voucher strip is in alignment with severing knives 474, 475, as shown diagrammatically in Fig. 4A. A feed roll 444, Fig. 11, now operates to feed the strip backwards 1“, whereupon the feed roll is disabled and an electroroll 446 becomes effective to feed the strip forwards 3" and, in so doing, impresses the constant matter on the body and stub and positions the strip for first print and perforation. After these operations have taken place, the electroroll is disabled and the feed roll advances the strip a further 1¢". Second print and severing now take place and the voucher is issued by a roll 478. In all multipleitem operations in which the voucher mechanism is enabled, a voucher of the type shown in Fig. 36 is printed. In multiple-item entering operations, the electroroll 446, Fig. 11, is disabled and feed effected solely by the feed roll 444. In the first item-entering operation, the strip 460, Fig. 48, is first retracted 1“" from the position shown at A to that shown at C and is thus fed forwardly 3" to the position shown at D when the item is printed. In the second and each subsequent item-entering operation, the strip is first retracted ¢" to the position shown at E and then advanced ¥" to the position shown at F to line space the items by “". In the second cycle of the ensuing multiple-item total-taking operation the strip is retracted 2¢" by the feed roll to the position shown at G, and advanced 3" in two equal stages by the electroroll to the position shown at H thereby spacing the total ¢" from the last item and impressing the constant matter on the voucher. After the first total print and perforation, the strip is fed a further 1¢" to the position shown at I where the second total print is effected and the severed voucher is then issued. The feed and electro pressurerolls 445, 447, Figs. 11 and 22, are carried by eccentrically-mounted shafts and are alternatively operable to render the feed roll or the electroroll effective to feed the voucher strip. The eccentrics are controlled by toothed arms 568, 569 loose on a shaft 570 and provided with studs 571, 572 embraced by slots in a 'plate 575. In each single-item and multipleitem total-taking operation, the cam plate receives a clockwise and counterclockwise rocking from a cam 593, Fig. 21, that makes one clockwise revolution in each machine operation, the connections including a cam follower 589, notched driving plate 582, pin 583, slotted bell-crank 581, shaft 578, Fig. 22, and toothed sectors 577, 576. The pin 583, Fig. 21 is carried by an arm pivoted on a stud 587 slidable in a slot in an arm 585 of the shaft 355, the arrangement being such that, in multiple-item entering operations, the connection between the cam 593 and the plate 575, Fig. 22, is crippled to enable the feed roll throughout the operation. The electroroll 446, Fig. 11, is driven from the sleeve of shaft 501, and is thus disabled in multiple-item entering operations. The feedroll 444, Figs. 11 and 30, for the voucher strip is driven from cams 500 on the shaft 501 that makes one clockwise revolution in each machine operation in which a voucher is to be issued. The connections include a cam follower 510, a shouldered lover 488, Figs. 30 and 31, a latch 486 pivoted to a toothed sector 484, integral gears 483, 482, wide pinion 516, gear 480 coaxial with the gears 483, 482, and gear 479. The wide pinion 516 is controlled by a cam on shaft 501 and is rocked out of mesh with the gears 480, 482 for a short period in each operation, an aligning pawl 526 being simultaneously engaged with the gear 479 to lock the feed roll. The toothed sector 484 is rocked clockwise and counterclockwise to rotate the feed roll first backwardly and then forwardly, the latch 486 being variously controlled in accordance with the type of machine operation by the engagement of its stud with a series of adjustable abutments to vary the extent of f