Patent GB-274694-A (GB)
Title: Improvements relating to web-feeding arrangements for typewriting machines
IPC: B41J17/00
Filed: 1926-11-16
Abstract: 274,694. Fairweather, W. C., (Underwood Typewriter Co.). Nov. 16, 1926. Web-feeding arrangements; linespacing mechanism; ink-ribbon mechanism. - Relates to web-manifolding arrangements of the kind in which carbon sheets interleaved with a multiple or fan-folded web are carried by a trolley which is transviersed with the web until a section is typed and is then retracted, and comprises trolleytraversing means actuated by the linespacing mechanism and so arranged that the platen and feed-rollers are relieved from the drag of the trolley and web, slip being thereby prevented. The apparatus shown in Figs. 1 and 4 comprises a table 39 secured to the carriage, 12 of a typewriter and provided with rails 50 supporting a. trolley 48 having blades for holding carbon sheets, the platen 23 of the typewriter being equipped with line-spacing mechanism including a lever 15 actuating a pawl-slide 18. The pawl-slide is now connected by a link 26 to a lever 31 engaging a recess 34 in a rack 58 having shouldered studs 60 which engage slots 61 in plates 64 securea to the name 39, the slots having inclined ends 62, 63. The rack co-operates with a normally disengaged pawl 75, Fig. 5, which is pivoted on a bracket 71 on the trolley and has a notch 77 engaging a stop-pin 78, a spring 80 holding the pawl in forward position. The multiple web 54, interleaved with the carbon sheets, is clamped to the trolley by means of a clamp 111, described below, which enters a grooved plate. 110. During the initial movement of the lever 15, the platen remains stationary and the rack 58 is caused by the inclines 62 to engage the pawl and impart a short traverse to tbe trolley, the web being thereby slackened slightly. On further movement of the lever 15, the studs 60 ride in the straight parts of the slots 61, the platen is rotated, and the webs receave linespacing feed, the trolley being traversed with the webs and thereby maintaining the slack therein. In the final part of the movement, of the lever 15, the studs enter the inclines 63, thereby disengaging the pawl 75, and the platen takes up the slack and completes the line-spacing feed of the web. Owing to the actuation of the trolley by the line-spacing mechanism, and also to formation. of slack on the web by the trolley, slip between the platen and web is prevented, the platen and associated feed-rollers being relieved from all drag except that required to feed a short section of the web. On release of the lever 15, the rack is returned by a spring 68 aided by the pawl-slide spring 19. During return, the rack passes idly over the pawl and the studs 60 enter the inclines 62. Web-clamping arrangements.-The clamp 111, Figs. 1 and 4, is secured to arms 94, 95 which are carried by a rock-shaft 96 on the trolley 48 and are drawn downwards by springs 92. The clamp 111 is raised to release the web by pushing rearwards a slide 105 having pin-and-slot mounting on a handle 89 secured to the trolley, the slide being connected to a leverr 101 having a roller 99 engaging a slot in the arm 95. The slide and handle have finger-pieces 109, 108. Web-guiding arrangements.-When a web consisting of separate plies is employed, only the outer ply 128, Fig. 9, is tensioned, and other plies 125 being allowed to sag, and when the carriage is out of the middle position the ply 128 is unevenly strained on operation of the line-spacing mechanism and is liable to tear at one edge. To equalize the strain on the ply 128 there is now provided a guide-bar 140 which is pivoted a,t the centre and can rock to skew the web during movement of the carriage. The guide-bar may have a central pivot entering a socket 136 on a bracket 131 detachably clamped by a screw 132 to the rear bar 41 of the table 39. The guidebar preferably consists of a sheet-metal member reinforced by a cross-bar and a cross-rod 141 mounted in ears 138. The cross-bar may carry side gauges 139.