Patent GB-766781-A (GB)
Title: Improvements in a tape feeding unit for a typewriter, recording or like machine
IPC: G06K13/26
Filed: 1954-06-17
Abstract: 766,781. Typewriters; winding and unwinding webs. REMINGTON RAND, Inc. June 17, 1954 [June 29, 1953], No. 17819/54. Classes 100(1) and 100(4) A tape feeding unit for a typewriter, which in addition to producing a visual record in the normal way also records coded data in a magnetic tape 429, comprises a supply spool 428 and a take-up spool 433 rotated by a capstan 426 driven by an endless belt 459 when the latter is coupled to the movement of the typewriter carriage by a clamp 461. In place of keys effecting type-levers they may effect punching of cards or sheets and the tape magnetized or punched without the use of decoding mechanism. The clamp 461 grips the inner reach 575 during typing to effect letter spacing and during a carriage-return movement to effect a feed of less than a letter-space. The spools 428 and 433 are axially mounted on a mandrel 427, and the tape 429 is guided by rollers 438 through a tension compensating device 434-436 across an erasing head 255 and the data recording head 205, over the capstan 426, and around rollers 439 to the take-up spool 433. The initial threading is effected by a "loading operation" in which a lead strip 432, Fig. 2, is attached at one end to the spool 433 and at the other by a spring clip 431, to the leading edge of the tape. During a loading operation the belt 459 is unclamped from the typewriter carriage and the capstan 426 driven by a power driven pulley 446, Figs. 1 and 4, which is mounted on a movable arm 448 so that it engages the inside of a rim 444 of the belt pulley wheel 442. The pulley 446 may be swung to engage the hub 443 of the pulley to effect a reverse drive or a "rewind" operation and into a "neutral" position when the capstan is being driven by the belt 459. There is a clock spring 591, Fig. 7, connected between the two spools so that the charging diameters of the tape is automatically compensated for and in order that the spring does not become overwound a slip clutch 584, 587, 588 is interposed between the spools. When a new reel 428 has been placed on the mandrel 427 and the lead-strip connected to the tape a handle 466 on the side of the unit is pulled-forward and a shaft 463 rotated. This moves an actuator lever 476, Fig. 14, and rotates a detent disc 472 and a control cam 497, which moves a depression portion 501 adjacent to a follower 504 allowing a yoke 506, pivoted at 507, to move and turn a sleeve 522 counterclockwise, Fig. 4, and cause an extension 505 to push a clamp bar 515, rotate a crank 578, and release the clamp 461 from the carriage driven belt 459. Also the sleeve, through a spring link 510, 526, actuates the arm 448 so that the drive roller 446 engages the rim 444 and effects a fast drive to the capstan 426: the lead strip pulls the tape up to the recording head, whereupon the fast feed stops and the tape-feed is controlled by the belt 459, now engaged by the clamp 461. This change-over of feed is effected by a projection 454, Fig. 7, attached to a nut 453 which travels on a threaded extension of the capstan 426, and after an axial travel corresponding to the length of the fast feed, operates a lever 517 to cause a loading detent 513, Fig. 14, to free a control disc 498 and bring a "neutral" position 502 of the cam 497 to the follower 504 whereupon the yoke 506 effects a disengagement of the roller 446. The tape-feed is now under the control of the carriage controlled belt 459 but when recording is completed the handle 466 is again operated to effect a "rewind" operation. The actuation of the handle operates the pawl mechanism 479, 472, Fig. 14, and a further advance of the control cam 497 is made which disconnects the clamp 461 and shifts the drive pulley 446 to engage the hub 443 of the pulley wheel 442 so that a very fast "rewind" takes places. The inner wall of the take-up roll 433 is provided with an arcuate spring strip 531, Fig. 4, which swings out when the lead is nearly unwound to operate a crank 534. This rocks a detent 509 free of the control disc 498 which turns until detent disc 472 is again arrested by a trigger 493, whereupon a "neutral" position 502 of the control cam 497 operates the yoke 506 bringing the driving pulley 446 out of engagement with the hub 443. At this time a cover latch cam 471, Fig. 14, releases a catch securing the cover. A pin 539, Figs. 4 and 7, projecting upwardly from a lever 542 is raised when the cover is removed to release a bell-crank 543 and permit pawls 547, 548 to lock the spools against rotation.