Jig for holding long workpieces, esp. bars during anodising - where bars are supported by metal frame conducting electricity, and one or more perforated polymer plates

摘要

The jig consists of two frames (a,b). One frame (a) is made of an electrically-conducting material so it can supply electricity to the workpieces, whereas frame (b) is made of a non-conducting material, pref. a polymer plate made esp. of polypropylene. More than one frame (b) may be used, e.g. when treating very long bars. Frame (a) has spacer rails used to support the workpieces, which enter holes in the polymer plate (b). For long bars with a round cross-section, the holes in plate (b) are pref. polygonal, but are round when the bars have a polygonal cross-section, i.e. the min. contact surface is achieved in both cases. The polymer plate (b) is not affected by the electrolyte; and the workpieces do not need to be clamped to the jig so time is saved.