Patent GB-179120-A (GB)
Title: Improvements relating to the carriage of a typewriting machine with visible writing
IPC: B41J19/74
Filed: 1921-01-28
Abstract: 179,120. Sßndor, F. Jan. 28, 1921. Paper-carriages; platen-shift mechanism.-Relates to visible-writing machines having the platen frame pivotally mounted on pivoted arms on the carriage, and comprises arrangements whereby, (1) the platen frame can, in any position of the carriage, be raised to an abnormal position in which the paper is accessible for making connections, and (2) the platen roller isvirtually rotated during the shift movement to bring the tangent plane at the printing line into the vertical plane and thereby prevent the type from striking capitals with weak tops. In the preferred arrangement, the side plates 14 of the platen frame are pivotally mounted in the forked ends of arms 6 which are pivoted by pins 5 to lugs 3 on the carriage 2. The shaft 11 of the platen roller 12 passes through sleeves 8, Fig. 4, formed on bushes 7 secured to the forks, the plates 14 rocking on the sleeves. The pins 5 can be retracted to permit detachment of the platen frame and arms 6 from the carriage. Bars 16, 17 connecting the plates 14 carry a roller 19 running on a rail 20 formed on a plate 21 which is movable vertically by shift mechanism. When the plate 21 is shifted, the arms 6 move upwards through the arc F, and the platen-roller is virtualy rotated clockwise through an arc G to bring the tangent plane at the printing point B<1> into the vertical plane. The arms 6 enter recesses 15 in the plates 14, the edges 22 of the recesses engaging the arms 6 to limit the relative movement of the platen frame. The platen frame can at any time be raised, by means of a finger-piece thereon, to the abnormal position shown in Fig. 8, in which position the last-printed line is above the level of the ink ribbon and is accessible for making corrections. The platen frame is automatically retained in the raised position bymeans of a pivoted plate 41 which is swung outwards by means of a spring-actuated lever 35 and engages a rod 18 on the platen frame. The plate 41 is released, to permit lowering of the platen frame, by operating push-keys 31 engaging a bail 26 which is pivoted on the rod 18 and is provided with a finger 28 engaging a projection 37 on the lever 35. Sheet feeding and guidinq arrangements; dust excluders for actions.-An apron 53, pivotally mounted on spring-actuated rocking arms on the rod 18, supports feed-rollers, and a pivoted presser-plate 44 which, when the platen frame is in the abnormal position shown in Fig. 8, is turned downwards to prevent the erasings from dropping into the action. When the push-keys 31 are operated, the plate 44 is moved into contact with the platen by means of links 45 having slots 47 engaging pins 46 on the bail 26. The apron 53 can be depressed, to release the feedrollers, by means of a thumb-lever connected by a link to a bail which engages the rocking arms that support the apron. The thumb-lever is provided with a catch. Carriage stops.-The cross-bar 17 of the platen frame supports carriage stops 25 which are accessible for adjustment when the platen frame is raised.