Die-cast components for ball-point pens - are made of metal to close tolerances, avoiding machining

摘要

A ball pen has its pointed end which houses the ball made of zinc by pressure die casting. This reduces the cost of manufacture compared with turning such parts from metal bar. On the other hand a much stronger article is produced than those made from moulded plastics material. Pressure die castings in zinc enable the screw threads (11) to be cast with sufficient accuracy to fit the body of the pen. A further improvement in the quality of the casting can be achieved by pressure die casting under vacuum, to produce a component made to close dimensional tolerances.