Abstract:
A powder spray apparatus for coating threaded fasteners capable of operating at an optimum spray condition. Air supply and powder supply tubes communicate within an air/powder entrainment block. The jet diameter of the air supply tube is sized to provide an optimum spray condition at which a constant supply of powder is provided through a powder spray tube at an optimum powder density and velocity. These powder density and velocity conditions maximize the powder build rate on the threads of the fastener, and also increase production rates. The resulting coated fasteners exhibit a low torque scatter, and a highly uniform patch. A method for operating a powder spray apparatus at the optimum spray condition also forms part of the present invention.
Abstract:
A method and apparatus for coating a fastener, particularly a fastener with a head portion and shank portion, with a coating material is provided. The invention includes the steps of and apparatus for supporting the fasteners such that the fasteners are positioned for coating. The fasteners are conveyed such that the fasteners are moved through a plurality of operation stations and pass through 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 supporting the fasteners on their head portions with the shank portions projecting upward, conveying the fasteners with their shank portions projecting upward for processing, 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.
Abstract:
A method and apparatus for spraying powder material from a plurality of nozzles. A powder material feed control section and a manifold section provide a uniform flow rate and uniform density pattern for a powder material feed stream sprayed from a plurality of nozzles.
Abstract:
A process and apparatus for manufacturing self-locking fasteners in which a resin deposit of patch is applied to a portion of the threads. A resin stream entrained in a gaseous jet is directed through a nozzle which is an axial registration with the fastener. The nozzle has an end wall and an arcuate slot therein which directs application of the entrained resin to the threads of the fastener in a controlled manner.