Patent GB-191501497-A (GB)
Title: Improvements in or relating to Line-spacers for Typewriters.
IPC: B41J19/76
Filed: 1915-01-29
Abstract: 1497. Etheridge, H., and Bar-Lock Typewriter Co. Jan. 29. Platen-rotation for condensed-billing, blanking, &c. Relates to mechanism of the kind in which the platen is operated through movementmultiplying gearing by a hand-lever, and comprises a platen-driving member rotatable about the axis of the platen and adapted to be coupled to the platen by a two-way clutch operated by a movable controlling-device, which sets and releases the clutch in moving from and to its normal position. The controlling-device can be adjusted so that the backward feed is greater or less than, or equal to, the forward feed, or so that the feed is in one direction only. In the arrangement shown, a driving member or pinion C, loose on the platen shaft A<1> and gearing with a sector B<2> on a handlever B, is provided with a disk C' carrying pawls D, D' adapted to engage ratchet-wheels E, E<1>, which are secured to the platen shaft and are formed with oppositely-facing teeth. In the normal position, the hand-lever is disconnected from the platen by the engagement of a controlling-device or shield F<2> with the tails of the pawls, the shield being mounted on an arm F, which is loose on the platen shaft and is connected to a spring G, which holds a hook F<8> on the shield against a stop B<3> on the sector B<2>. A spring B<4> normally holds a stop on the sector against the pinion C. The shield is formed with shoulders F<4>, F<5> and a tongue F<3> and is mounted for lateral adjustment on the arm F by means of studs F<6> engaging slots F<7>. On lifting the hand-lever, the disk C<1> is rotated anti-clockwise, Fig. 3, the tails of the pawls moving from under the shield, owing to the pin B<3> compelling the shield to move at a slower rate than the pawls. When the tails of the pawls leave the shield, springs D<2>, D<3> move the pawls into engagement with the ratchet-wheels, the pawl D being operative. At this stage, a. stop G<2>, formed on a stop-member G<5> pivoted on the disk, engages a finger G<1> on the arm F and carries the shield round with the disk. In the return movement of the handlever, the pawl D<1> is operative, and towards the end of the rotation, the shield comes into position to release the pawls. The movements of the hand-lever are limited by the stop, referred to above, on the sector and bv the engagement with the platen shaft of an adjustable stop secured to an arm B<6>, which is locked by the engagement of a spring-pressed pin B' with holes in the sector. For condensed-billing, the shield is set, according as the machine is fed from the front or the rear, (1) with the tongue F<3> and the shoulder F<4>, or (2) with the tongue F<3> and the shoulder F<5> over the tails of the pawls D, D' respectively, thus causing the anti-clockwise rotation to be greater than the clockwise rotation, or vice versa. The difference between the anticlockwise and the clockwise rotations causes the sets of entries on the record-sheet to be spaced apart. For purposes, such as addressing envelopes, in which equal rotations are necessary, the shield is set with the tongue F<3> over the tails of both pawls. For rotating the platen in one direction only, the stop - member G<5> is moved by its finger-piece, to bring it finger G<3> into the range of the finger G<1>, and the shoulder F<4> or F<5> is set over the tail of the pawl which is to be operative. The parts are timed so that the shield is carried onwards by the finger G<3> before the tail of the inoperative pawl leaves the tongue F<3>.