Method of manufacturing a plastic camshaft with a tubular metal insert

摘要

A method of manufacturing a plastic camshaft (20) having a tubular metal insert (22) using a die assembly (40) having a pair of aligned pins (50, 52). The tubular metal insert is cut to a length slightly shorter than the length of the finished camshaft and is placed on one (50) of the pins. The second pin (52) is then inserted into the opposite end of the tubular metal insert during the closing of the die assembly. The pins properly align the metal insert within the mold cavity of the die assembly during injection of a surrounding plastic material which forms the remainder of the camshaft. The pins also axially compress the tubular metal insert and have tapered shoulders (58) which bear against and slightly deform or flare the end regions of the insert. The flared ends of the tubular metal insert (22) tightly engage the pins and prevent the formation of flash within the hollow interior of the tubular metal insert.