MULTIPLEX TYPEWRITER FOR TECHNICAL DRAWINGS

摘要

The invention provides a multiplex typewriter for lettering technical drawings in Standard Technical Style and Sizes as fixed by The National Standards for Lettering Technical Drawings using a new method whereby any "National Standard Alphabet and Numerals for Lettering Technical Drawings" may be used on typing element faces. The apparatus and method permit lettering drawings by typing, and having the following possibilities: (1) All standard sizes of technical drawings can be accommodated by the machine, (2) A single machine can use as many as nine different standard sizes of given national standard alphabet and numerals. In a particular embodiment several typing keyboards are mounted on a stationary table around a vertically movable and rotatable common platen, this platen sliding over a stationary column, being movable vertically by a group of mechanical means driven by step motor drive, and being rotatable by another group of mechanical means driven by separate step motor drive. These drives are operated by a computer activated by any one of nine program selector devices each actuating selectively a ball type lettering head (in the case of keyboards equipped with such heads), or actuating normally a set of keys (in the case of keyboards equipped with keys).