Patent GB-190105061-A (GB)
Title: Improvements in Typewritting Machines.
Inventor: FELL JOHN CORRY
Filed: 1901-03-09
Granted: 1901-06-01
Abstract: 5061. Fell, J. C., [Smith Premier Typewriter Co.]. March 9. Type-writers.-Relates to automatically-reversing inking-ribbon mechanism in type-writers, and to means for securing the ribbon to the spools. The invention is described as applied to the Smith Premier machine. The ribbon is of considerable width, and is carried by spools 2 bearing crown ratchet-wheels 3 on their front flanges. In Fig. 3, the spool 2 is shown with the ribbon removed. The spools are slidably mounted on horizontal shafts 4, and are embraced by the arms 5 and 6 of a ribbon-carrier or frame 7, Fig. 4. The arm 5 has a rearwardly-directed extension 9, provided with a vertical slot engaged by a pin on a vibratory driving-arm 12 carried by a rock-shaft 13. The rock-shaft is reciprocated from the paper-carriage driving-mechanism, so that the ribbon moves widthwise during the carriage feed. With the ratchetwheels 3 are adapted to engage pawls 14, 15, of which one or other is always out of action. The pawls are provided with horizontal teeth 14<a>, Fig. 4, to engage the ratchets, and with upward extensions 34 for a purpose to be subsequently described. During the forward traverse of the spools on the shafts 4, that spool with which a pawl is in engagement will be rotated as it gradually pushes the pawl upwards. During the rearward movement, the pawl slips over the teeth of the ratchet, and the spool does not turn. Adjustable friction springs 35, Fig. 1, bear on the faces of the spools to prevent accidental turning. The automatic reversal consists in substituting one pawl for the other so as to set the emptied spool in rotation and release the full one. This is effected as follows :-When a spool is nearly empty, the fingers 29 of a pivoted plate 25, Figs. 3 and 4, drop into openings 32 in the core 1 of the spool, thus causing an arm 30 to swing into line with the upward extension 34 of the disengaged pawl. The arm 30 is bevelled at the end so that it moves aside to clear the pawl at the moment that the spool reaches the limit of its forward movement, but the arm, being thus engaged in the front of the upward extension 34, drags the pawl to the rear as soon as the spools commence to return. This rearward movement of the previouslydisengaged pawl is made to disengage the other by means of mechanism shown in Fig. 3. The rearwardly-moving pawl 14 acts on the arm 17 carried by a rock-shaft 18, thus causing the arm 23 carried by the same shaft to disengage and throw forward the pawl 15 by operating on its downward extension 24. A spring plate 19 carries a snapping detent 20, which engages either above or below a fixed roller 21, so that the full reversing movement of the pawls is necessarilly effected. The ribbon is attached to the spool in the following manner ;- The core 1 is slotted circumferentially at 40, Fig. 6. A plate or bail 41, Figs. 7 and 4, is curved at 38 to fit the surface of the core, and is provided with teeth 39 registering with the slot 40. The bail 41 is pivoted to the inside of the spool flanges at 42, and, the end of the ribbon having been laid on the slotted portion of the core, the plate is forced against it, so that the teeth enter the ribbon and engage in the slots. The tension in the ribbon is always such as to tend to draw the bail into closer engagement with it. The bail is shown in dotted lines in Fig. 4 withdrawn from the core for the insertion of a new ribbon. Reference is made to Specification No. 25,123, A.D. 1894.