Patent GB-1143728-A (GB)
Title: Apparatus for the incremental lengthwise feeding of a strip of record material
IPC: G06K15/16
Filed: 1967-09-12
Abstract: 1,143,728. Selective printing. NATIONAL CASH REGISTER CO. 12 Sept., 1967 [29 Sept., 1966], No. 41499/67. Heading B6F. Line-spacing.-In a multiple-strip listing machine, each strip may be fed lengthwise in increments for line spacing by a feed roller 72 driven by a motor 102 which is actuated by a pulse from printing mechanism 50, the roller 72 coacting with a shoe 70 having a smooth face over which the strip slides, the shoe being urged towards the roller 72 by a spring 96 and being liftable out of contact with the strip by a solenoid 74 acting against the spring 96, the pulse from the printing mechanism selectively de-actuating the solenoid 74. Only two strips may be advanced simultaneously. The roller 72 may be covered with a layer 100 of elastomeric material, and the smooth surface of the shoe 70 may be coated with a substance of low coefficient of friction such as polytetrafluoroethylene or chromium on nickel. The pulse from the printing mechanism operates two flip-flops (276, 314), Fig. 17 (not shown), one of which (276) energizes the motor 102. The motor 102 drives a generator 308 which stabilizes the motor, and a disc 322 which controls the stopping of the motor, as well as the rollers 72. The disc 322 is formed with transparent sectors and is located between two lamps (330, 332, Fig. 17) and corresponding photoelectric cells (326, 328). The photo-electric cells produce alternate pulses, a first pulse resetting the second flipflop (314) the output from which then cooperates with a second pulse to open an AND gate (320) and reset the first flip-flop (276), thereby stopping the motor 102. Switches (344) can be operated to effect continuous feed. Multiple web arrangements; tensioning devices.- Six strips are juxtaposed, each having a corresponding shoe 70and roller 72. The rollers 72 are fixed to a common shaft 82 driven by the motor 102. Each feed mechanism 40 may feed two superposed strips 56, 58, the strips being fed from separate receptacles 52, 54 past a tensioning device 60 and separated after the feed mechanism 40. The tensioning device 60 comprises a pivoted plate (108), Fig. 13 (not shown) urged towards the printing table (112) by a spring biased plate (114). The lower strip 58 passes between the pivoted plate (108) and the table (112), and the upper strip 56 passes between the two plates (108, 114). Adevice 80, comprising a plate (255), Fig. 7 (not shown), provided with a rubber lower edge and spring urged towards the table, prevents the strips from reverse feed due to the printing mechanism 50. The receptacles 52, 54 are mounted on a detachable unit 32 and the receiving receptacles and feed mechanism 40 on a detachable unit 42. Type carriers, hammer impression arrangements.-Impression hammers 68 are selectively operable in timed relationship with a rotating drum 62 carrying peripheral printing characters. An ink ribbon 66 effects an impression on the upper strip 56 and chemical coatings interact to effect a duplicate impression on the lower strip 58. Locking devices.-Detector switches (234, Fig. 7 and 410, Fig. 2, not shown) prevent the feed mechanism 40 from operating in the event of a broken strip or in the absence of a strip.