Pantograph

Mechanical linkage used for copying drawings

A pantograph (from Greek παντ- 'all, every' and γραφ- 'to write', from its original use for copying writing) is a mechanical linkage connected in a manner based on parallelograms so that the movement of one pen, in tracing an image, produces mimic movements recorded by a second pen. If a line drawing is traced by the first point, an identical, enlarged, or miniaturized copy will be drawn by a pen or stylus fixed to the other. Using the same principle, different kinds of pantographs are used for other forms of duplication in areas such as sculpting, minting, engraving, and milling.

From Wikipedia, under CC BY-SA. More on occurri.