GB572073A - Improvements in typewriters and the like - Google Patents

Abstract

572,073. Typewriters &c. SCHEMBRI, C. Feb. 29, 1944, No. 3739. [Class 100 (iv)] A typewriter or like keyboard machine, e.g. type-setting machines, has means whereby a selected key can be operated in a repeat manner, e.g. for underlining or cancelling, by the movement of a member common to all the keys from which repetition operation may be required. For this purpose, a rack 1 mounted on the carriage may be raised to engage a pinion 4 forming part of gearing 7 ... 15 so as to rotate a shaft 15 carrying cams 15a, 15b, when the carriage is moved endwise. Each key-lever 16 is provided with a projection 24 which is engaged by the cams when a key is depressed so that by keeping the key depressed and sliding the carriage with the rack 1 raised, the cams cause repeated operation of the key. The rack 1 is normally held in depressed position by springs 17 attached to pins 22 on the rack which pass through cam slots 23 in a fixed plate 18. A lever 18a or sliding member mounted on the carriage adjacent to the usual roller-knob 28 is provided to raise the rack 1. The shaft 15 of the cams 15a, 15b has radial fingers riding between two spring-pressed blocks and so situated relatively to the cams, that when the shaft 15 is not being driven, they are held by the blocks with the cams in an inoperative position.