Patent GB-349619-A (GB)
Title: Improvements in or relating to automatic ribbon reversing mechanism for cash registers and similar accounting machines
IPC: B41J33/00
Filed: 1930-03-01
Abstract: 349,619. Ink-ribbon mechanism. NATIONAL CASH REGISTER CO., Dayton, Ohio, U.S.A.-(Assignees of Shipley, B. M. ; 2021, Catalpa Drive, Dayton, Ohio, U.S.A.) March 1, 1930, No. 6823. Convention date, March 5, 1929. [Class 100 (iv).] Automatic reversal.-Feed-pawls for the ribbonspools are controlled by a single disc having alternate high and low parts for causing one pawl at a time to be effective. In the mechanism shown in Fig. 1, ratchet-wheels 60, 61 connected to spools 32, 31 cooperate with pawls 70, 71 on a bell crank 62 which is rocked by means of a key-coupler 82 operated by the key-levers 83. A lobed disc 77 co-operates with pins 78, 79 on the pawls and is connected to a ratchet-wheel 98 co-operating with a pawl 94 which is carried by a rocking arm 96 and is connected to an actuating spring 93. The disc co-operates also with pins 99, 110 on rocking arms 100, 111 having rollers 102 riding on the flanges 52, Fig. 2, of the spools. Each flange has, as described in Specification 231,868, [Class 100 (iv), Typewriters &c.], a recess which is normally bridged by a pivoted ring 91 having a lip resting on the core of the spool or, preferably, in a slot 89 therein. When the spool 31 is winding, the disc 77 permits the pawl 71 to engage the ratchet wheel 61, and one of the lobes 76 engages the pins 78, 99, thereby holding the pawl 70 out of engagement and preventing movement of the ratchet wheel 98. When the spool 32 is nearly empty, the ribbon 30 uncovers the lip of the associated ring 91, the arm 100 displaces the ring, the pawl 94 actuates the ratchet wheel 98, and the disc 77 co-operates with the pins 79, 78 to disengage the pawl 71 and permit engagement of the pawl 70, the feed being thereby reversed. The spool 32 operates to wind the ribbon until the spool 31 is nearly empty, whereupon the pawl 94 is permitted to reverse the feed in the abovedescribed manner. If the spring 93 fails to actuate fully the pawl 94, movement of the ratchet wheel 98 is ensured by means of a pawl 115 on the bell crank 62. A pin 104 on the bell crank 62 cooperates with the arm 96 to restore the pawl 94. The spools 31, 32 are mounted in a frame consisting of plates 33, 34, pins 35, 36 on the plate 33 entering tubes 38 on the plate 34, and the plate 33 carrying a pivoted catch 41 which engages the grooved end of a projecting rod 40. On release of the catch, the plates can be disconnected to permit of removal of the spools. The frame is, as described in Specification 349,618, provided with headed studs 42, 43 for detachable engagement with slots 44, 50 in the framework of a cash register or like machine. Spools; brakes.-Each spool consists of a tube having lugs 49, Fig. 2, for securing the flanges 52, 53. The flange 52 is supported by a trunnion 54 mounted in the plate 33 and formed with a flange 58 which is coupled to the flange 52 by a pin 59. The flange 53 is supported by a thimble 55 which is mounted on a stud 56 on the plate 34, a spring 57 in the thimble causing the flange 52 to bear on a collar 48 on the trunnion and thereby press the flange 58 into contact with the plate 33 and brake the spool. The ratchet wheels 60, 61 are secured to the trunnions.