GB1199832A - Rack Escapement Mechanism for Typewriters, Accounting Machines or Like Machines - Google Patents

Abstract

1,199,832. Typewriters &c. OLYMPIA WERKE A.G. 26 April, 1968 [26 May, 1967], No. 19866/68. Heading B6F. A typewriter rack escapement mechanism is provided with a half-letter-spacing mechanism for an error correction space key, the half-letterspacing mechanism including a slidably and pivotally mounted pawl 7, the tooth 6 of which is in engagement with the teeth 24 of a spring biased paper carriage rack 23 and a release lever 19 pivotally mounted in a recess 17 of a spacer 3 and articulated by a link 20 to the space bar (not shown) forming the correction key in its depression position, in which a lug 21 on the release lever 19 abuts a lug 10 on the pawl 7, whereby the distance between lugs 10 and 21, when in their inoperative position, corresponds to half a letter space. When the space bar is released the carriage is enabled to move through a further half-letter space for completion of the letter-spacing escapement movement. To effect an error correction, e.g. by typing an additional letter between two consecutive letters in a word, the space bar is depressed and held in its depressed condition, thereby the lug 21 on the release lever 19 pivots the pawl 7 out of engagement with the rack 23 and a spring 9 causes the pawl 7 to be drawn to the right and into engagement with the following rack tooth. Meanwhile an inclined surface 22 on the lug 21 slides off a complementary surface 11 on the lug 10 to dispose the lug 21 in the path of the lug 10, which is displaced towards the lug 21 by the letter-spacing movement of the paper carriage which is thus arrested in the half-letter-spacing position. On release of the space bar the release pawl 19 is restored to its original position and the carriage thereafter moves a further half a letter space until the lug 12 on the pawl 7 abuts a stop surface 13 on the spacer 3 fast with the typewriter frame. Multiple-action keys.-The space-bar (not shown) is depressed (and held down for error correction) to effect half a letter spacing and then released to complete the full letter spacing.