Compasses for drawing circles - incorporates clamp mechanism with screw and friction surfaces

摘要

The pair of compasses comprises a head with grip and bow fitted plate jaws taking the compass legs. The leg position can be varied by a clamping screw which spreads or converges the plate jaws as required. A clamp (30,30') on each leg (20,20') should project into the area of the other leg to act as a friction element (3) composed of cooperating rubbing surfaces (31,31') and opposed clamping faces (32,32'). The clamping faces bear on the insides of the tensioning plate jaw (11) and of the clamping plate jaw of the head (1) and are pressed permanently onto these and held together at their friction surfaces by means of the clamping screw (41). USE/ADVANTAGE - Drawing offices. Compass legs can be variably set and held in this setting as long as required.