Polygon nut spanner with interchangeable inserts - has hinged jaws with teeth fitting polygon inside

摘要

The spanner is in the form of a pair of pliers, with the jaws (3) having teeth on the inside. The adjacent flanks of adjacent teeth (4) enclose an angle equal to that of a regular polygon, so as positively grip the nut (6) or bolt head between them. Between each pair of tooth gaps (5) fitting over the corners of the polygon there can be a further tooth gap. The teeth can be formed on interchangeable inserts, fitting in U-shaped jaws and held in place by screws, there being pressure springs acting between jaws and inserts. The jaw handles (1) can be held apart by a further spring (2). Inserts of different sizes can be provided, to suit different nut sizes.