Method and apparatus for coating fasteners

摘要

A method and apparatus for coating a fastener with head and shank portions is disclosed. The invention includes the steps of and apparatus for transferring the fasteners from a feed mechanism such that the fasteners are positioned for coating. The fasteners are then conveyed through a plurality of operating stations, beginning with a heating station where the shank portions of the fasteners are heated. Subsequently, at a material applying station, a coating material is applied to the heated shank portions. A preferred embodiment of the method and apparatus of the present invention includes using a magnetic holder to carry the fasteners horizontally by their head portions, where fasteners are centered by a rotating wheel, heating the shank portion to a temperature above the melting point of the applied material and applying the material to the heated shank portion to form a coating thereon. The magnetic holders are part of an endless traveling belt that rotates continually. The fastener carriers have teeth that engage a rack to rotate the fasteners. A conveyor provides added air cooling for the coated fasteners, which can continue to be rotated. Also disclosed is a transfer wheel with two sets of notches that is synchronously coupled to the traveling belt for placing and aligning fasteners on the belt for coating. Uncoated areas on the fasteners may be detected via sensors present beyond the powder spray station which may include a plurality of spray nozzles.