144,365. Haddan, A. J. H., (National Cash Repister Co.). March 6, 1919. Ticket-apparatus for checking, recording, and registering; printing-arrangements; registering and recording number and value. - Relates to ticket-printing apparatus of the kind described in Specification 143,821 wherein detachable destination-printing devices or matrices are inserted to print the destination and a serial number on the ticket issued and to control differential mechanism for actuating totalizing means and positioning type-carriers adapted to print on a detail strip the value of the tickets issued. The invention consists in the provision of interlocking means whereby the amount differential mechanism is locked against operation when a destination device is not inserted and a total or sub-total is not being printed, and a total or sub-total is prevented from being taken when a destination device is in the machine. Operation of the machine is also prevented when it is set for the issue of one kind of ticket, such as a single ticket, and a destination device for another kind, such as a return ticket, is inserted. The external handles operated to position the destination device and to set the machine for the kind of ticket to be issued are locked during an operation of the machine and conversely. The differential means comprise parts which are provided with feeling devices, cooperating with differential holes in the destination devices, as described in the above-mentioned Specification, and with similar parts without feeling devices which are only employed during totaling operations. Two locking devices for the differential means are provided, one locking means being disabled by an inserted destination device and both during a totalising operation. Operating. The clutch mechanism described in Specification 17534/08, [Class 106 (i), Calculating &c.], is employed and operated by the depression of a clutch key 116, Fig. 1, carried by a spring-retracted slide 113 moving on a shaft 103 and a cross rod 115. Inward movement of the slide removes a lug 110 from below a pin 108 on a crank 109 on the shaft 103 and releases the machine for operation. A second immediate operation of the machine, by the retention of the key in the depressed condition, is prevented by a second slide 130 connected to the slide 113 by a pin-and-slot connexion 118, 133 and by a spring 134. When the pin 108 is released by the lug 110 it passes between the lug and the end 135 of the slide 130 to hold it in the forward position, the pin moving in the slot and tensioning the spring 134. On the completion of the first movement of the machine the pin 108 rises above the fork end 135 and this under the influence of its spring 134 passes under the pin 108 and thus prevents a second movement of the shaft 103 until the key is returned to its original position. The destination devices, of the kind described in the above-mentioned Specification having serial-number and destination printing devices and differential value holes, are inserted at a shoot 165, Fig. 2, and supported in a pivoted frame 170, Fig. 4, by a rod 184 which is rocked to release the previously inserted destination device by a spring-retracted handle 190 through a sliding bar 197. During the operation of the machine, the handle 190 is locked against movement by a stop 226, Fig. 4, which is carried bv a pivoted arm 225 and is moved under a shoulder 227 on the bar 197, when the clutchoperating shaft 103 is rocked, through a crank 229 thereon and a link 228. Means are provided whereby the retention of the handle 190 in the lowered position, if moved after the motor key 116 is depressed, by friction between the parts is prevented, such means serving to prevent both the lever 190 and the key 116 being held in the operated condition. During operation of the machine, the frame 170 is rocked from its normal position to one in which the destination type is in the printing position and in which the value holes are so situated as to control the differential mechanism. Selecting kind of ticket issued. The issue of a return ticket, as opposed to a single ticket, is effected on rocking a handle 326, Fig. 4, fast on a shaft 327 thus adjusting a date printing and feeding roller 413 and causing it and the destination-printing platen to print twice upon a return ticket. Locking of the handle 326 during an operation of the machine -is effected by a roller 347 which engages one of two notches 346 formed in an extension of the handle, the roller being carried by a slide 348 rocked by a crank 355 on the clutch controlling shaft 103. Conversely movement of the handle prevents operation of the machine except when in the extreme positions. Preventing printing of ticket from wrong kind of destination device. Release of the machine when the lever 326 is in position for printing a " single " ticket and a " return " destination device is in the machine and vice versa is prevented by means of differently-positioned grooves 776, Fig. 6, formed in the destination devices which are adapted to be engaged by fingers 775 carried by two arms 750. One of the two arms 750 is fast on a sleeve 753 and the other on a shaft 743 to which are also secured respectively two arms 754 forked over pins 755 on levers 756, Fig. 1, retained in the normal position shown by springs 757. Pivoted on the cross bar 115 is a bell-crank lever 760 the lower end of which is slotted to engage a pin 768 on an arm 769 carried bv the shaft 327 of the lever 326. Pivoted to the other end of the lever 760 at 763 is an arm 764 bearing a pin 765 which engages a slot 766 in a lever 758 pivoted at 759 to the slide 130. The pin 765 is placed in front of the end of one or other of the levers 756, in the upper position for " return " and in the lower for " single " tickets. Movement to one of the set positions of the lever 326 rocks the shaft 327 and when the motor key is depressed the lever 758 moves forward, being prevented from being rocked clockwise by the spring 757 by a stronger spring 778, and the pin 765, through the lever 756 &c., rocks the corresponding arm 750 into its groove 776 in the destination device. If a wrong destination device be present the lever 756 cannot be moved and therefore the lever 758 is rocked by the pin 765 to bring an arm 777 thereof in front of a projection 1778 on the slide 130 which, being in contact with the pin 108, locks the motor key. Differential mechanism. The movements of totalizer pinions 502, Fig. 2, and type-carriers, secured to nested sleeves 514, for printing on a detail strip are controlled by the differential holes in the destination devices into which feeling devices 550, Figs. 2 and 12, carried by plates 530 are adapted to enter. The plates 530 are connected, together with rack-bearing members 517, by latch devices to plates 526 which are given an invariable movement from a cam shaft 77 through links 544, 540 and slotted levers 539. Pins 525, Fig. 12, on the bars 526 are engaged by notches 524 in spring-controlled latches 523 pivoted at 520 to the racks 517. When the feeler-bearing plates 530 are arrested by the ends of the differential holes in the destination devices, the latches 523 are rocked away from the pins 525, to break connexion with the plates 526, by relative movement between the parts 530, 527 allowed by pin-and-slot connexions 535, 536. On the return movement, the pins 525 engage noses 560 on the latches 523 thereby lifting them and the racks 517 relatively to the bars 530 during which movement the springs 522 rock the latches to normal position. The racks 517 are held in the lowered position by the wedge action of spring-pressed rollers 566 which act as a lock between fixed bridge pieces 574 and the inclined faces 369 of the racks. Locking higher differential elements during ncrmal operation. Four differential members 530 only are provided with feelers 550, the other members of this kind which control the higher order totalizing elements being similar in construction but unprovided with feeling-devices. To prevent movement of the higher bars 530 during operations in which destination devices are employed, a cross bar 580, Figs. 1, 2 and 14, of a pivoted yoke 583 is normally situated under the lower edges 585 of projections 532 on the bars 530, thus arresting these bars on the first movement of the driving-bars 526 and causing their disconnexion and that of the racks .517 therefrom. When a total or sub-total is being taken, the yoke 583 is rocked to remove the bar 580 from the locking position. Control, by a destination device, of lock for lower differential elements. No means are provided for preventing an attempted operation when a destination device is absent and a total or sub-total is not being taken but movement of the differential members controlled by the destination devices during such an attempted operation is prevented by the bar 589, Fig. 14, of a yohe 587 mounted co-axially with the yoke 583 on the shaft 327. The yoke is normally held by a spring 588 in position to strike the shoulders 585 of the parts 530 and release these and the racks 517 from the driving-members 526 at the commencement of the movement. The presence of a destination device rocks the yoke to an inoperative position by the engagement, with a destination device, of a finger 593, Figs. 2 and 14, of an arm 590 pivoted to the yoke 587. Movement of the yoke 587 does not affect the frame 583, a pin-and-slot connexion 736, 737 being provided for this purpose. Operation of yokes 583, 587 during total printing. During a total or sub-total printing operation the shaft 508 of a total control lever, moved from the normal to one of two positions, rocks, through an arm 735 thereon and intermediate connexions, a link 730, Figs. 1 and 14, connected to the yoke 583 thus moving it and the yoke 587, through the pin-and-slot connexion 736, 737, to an inoperative position. Preventing totalizing in p