Patent GB-625417-A (GB)
Title: Improvements in or relating to electric typewriters
IPC: B41J3/44
Filed: 1946-02-20
Abstract: 625,417. Typewriters. KATZ, L., NAMENYI-. Feb. 20, 1946, No. 31267/45. [Class 100 (iv)] In an electric typewriter comprising a platen roller 10 fixed against axial movement and a movable carriage on which is mounted typebars each having a number of type faces arranged along the length thereof transversely to the roller axis, electrically energized means are provided which under the control of the keyboard impart relative movement between a selected type-bar and the platen roller in a direction transverse to the roller axis for type selection, and also apply a striking movement to the selected type-bar. As shown, type-bars 23, Fig. 3, pivoted on a common arcuate spindle 24 each carries six type 22, three lower case and three upper case. The platen is moved vertically for case shift. Depression of a type key causes movement of the type-bars, up or down if the required type is the lower or upper one respectively of the set of three and at the same time causes the bar carrying the selected type to be moved to effect an impression. The spindle 24 is mounted in a member 25 guided for limited up and down movement by rollers 26 and guides 27, the member 25 being operated by an arm 58 on a shaft 17 normally held in a central position by spring arms 75. If a key corresponding to a lower type is depressed, an electromagnet 47 is energized and causes a hooked link 50 to engage a projection 49 on a shaft 16 driven continuously from a motor 15, Fig. 2B. The link 50 is moved to the left, Fig. 3, and by links 52, 54 turns the shaft 17 to raise the member 25. At the end of its movement, the link 50 is released from the shaft 16 by a stop 66 engaging its inclined nose, but the shaft is temporarily locked in its new position by a latch 62, described below, engaging a notched disc 60 thereon. Depression of a key corresponding to a higher type causes an electromagnet 48 to be energized-so as to actuate, a similar linkage 67, 69, 73, and move the shaft 17 and therefore the member 25 in the reverse direction. Neither of the magnets 47, 48 is energized, if the selected type is the central one of either set of three. For operating a particular type lever to print, each type-lever is connected by a link 90 to a lever 88 pivoted at 89 to the frame and at 87 to a link 86 similar to the links 50, 67. Actuation of a type key energizes one of a series of electromagnets 91 so as to cause the link 86 corresponding to the type-bar carrying the required type to engage the shaft 16 and thus impart a printing movement to the typebar. As the link 86 moves to the left, the toe 95 of the lever 88 operates a lever 98 pivoted to an arm 99 on a shaft 18. As the shaft 18 turns, cams 65, 84 thereon allow the latch 62 and a second latch 82 corresponding to the lower position of the member 25 to be pulled downwardly by springs, the latch 62 engaging the disc 60 if the member 25 moves upwardly and the latch 82 engaging a similar disc 79 if the movement is reversed. Release of the link 86 by a stop 94 allows the parts to return their initial positions. Platen-shift mechanism.-The platen-shaft bearings 11 are carried by arms 12 slidable in guides 13 and having teeth engaging pinions 14 on a shaft 38. Another pinion 37 on this shaft is continuously engaged by a slidable rack 32, which can be moved against the action of a spring 36 into engagement with a continuously driven pinion 35 by means of a keyactuated electromagnet 28. A latch 29 pushes the rack 32 against the pinion 35 and engages a shoulder 46 thereon to hold the platen in its raised position until the key is released. Letter-spacing mechanism; carriage-return mechanism.-The carriage 20 on which the type-levers are mounted is carried by endless bands 101 passing over rollers 102, 103. The shaft 105 of the rollers 103 is rotated for letter spacing by a spring 106, the action of which is controlled by an escapement mechanism including a pinion 111 on the carriage engaging a rack 110 on the frame. Carriage return is effected by coupling the shaft 143 of the rollers 102 to a continuously-driven shaft 40 by a clutch 104 operated by an electromagnet 107 controlled either manually or by feelers engaging the two edges of the paper sheet. Column stops.-To the underside of the rack 10, Fig. 1, is pivoted a series of column stops 119. When it is desired to tabulate, the selected column stops 119 are moved into line with an arresting member 120 on the carriage by hammer levers 116 actuated by link mechanisms and key-controlled solenoids similar to the parts 47, 50, 52, and the rack 110, which is pivoted at 112, is moved downwardly out of engagement with the pinion 111 by a keyoperated electromagnet 118, Fig. 2A. The stops may be cleared by a swinging-bar 117 operated by a solenoid energized by depression of a tabulating clearing key. Platen rotation.-The platen can be driven from the shaft 16 in either direction for feeding the paper into position or out of the machine by gearing which includes a driving gear 132 and a gear train 128, 130, 131 carried on a pivoted member 129. According to the direction of rotation required, one or other of two solenoids 134, 135 are energized by depressing a key, thus coupling either the gear 131 or the gear 130 with the gear 132. According to the Provisional Specification the band 101 may be motor-driven both for letter-spacing and carriage return.