Pantograph

摘要

Pantograph for drawings of buildings, earth strata, items found during excavations and the like with a fixed drawing board (1); a frame (2) which is rotatably mounted on the latter; a pulley (4) which is fixedly connected to the frame; a coil spring (10) which acts on the pulley (4); two deflection rollers (7) which are fastened to the frame (2); two strings (8) which are each wound onto the pulley (6) in the same direction, are each guided round a deflection roller (7) and converge on a moving pin (16); a carriage (13) which can travel along the mean perpendicular of the imaginary line connecting the deflection rollers (7); a drawing pencil (14) which is carried by the carriage (13) and acts on the drawing board (1); and a toothed wheel/toothed rod arrangement (5, 6) for moving the carriage on the mean perpendicular in dependence on the rotation of the pulley (4), the frame (2) being provided with at least three running rollers (3) which are supported on a circular path, the imaginary central axis of which coincides with the imaginary central axis of the pantograph.