pantograf

Pantograf, also spelled pantograph in English, is a term with two principal meanings. The name derives from Greek pan (all) and graphein (to write), reflecting its long association with copying and scaling drawings. In general use, pantographs are devices that reproduce movement or shape at a different scale, and they also refer to certain electrical current collectors on powered vehicles.

Mechanical pantographs are linkage-based drawing instruments. They consist of a set of rigid bars connected in a parallelogram configuration, with a tracing point at one end and a drawing point at the opposite end. As the tracing point moves over a drawing surface, the drawing point traces a copy at a fixed scale. By adjusting the link lengths or the pivot positions, users can achieve reduction or enlargement. Mechanical pantographs have been used by draftsmen, engravers, and mapmakers to reproduce complex images accurately, and they played a significant role in 18th- and 19th-century design and lithography. Today they are mainly of historical interest or used in teaching and specialized crafts.

Electrical pantographs are contact devices mounted on the roofs of electric trains, trams, and some electric buses. They consist of a hinged, spring-loaded frame with a contact strip or carbon shoe that slides along an overhead conductor (the catenary) to collect power. The design maintains consistent electrical contact while accommodating vertical motion and wind, and it has evolved into several variants optimized for speed, wear resistance, and aerodynamic efficiency. In railway engineering, pantographs are a critical component of overhead line systems.

Other uses include pantographs in manufacturing and sculpture for pattern replication and tool guiding.