Method and apparatus for applying a powdered resin to fasteners

Abstract

The present invention is directed to an improved method and apparatus for the application of powdered resins to threaded fasteners. In accordance with the present invention, the powdered resin handling system used to apply, collect, recycle and make-up the resin is generally enclosed; that is, with the exception of the application of the resin to the fasteners, the resin is generally maintained within conduit, housings or hoppers that are not open to the surroundings. This tends to minimize discharge of resin into the areas surrounding the fastener processing equipment and also isolates the resin from external environmental conditions that tend to degrade the resin over time. In addition, the present invention introduces fresh, new or make-up resin in a manner that assures intimate and thorough intermixing of the new and recycled resin while minimizing the cost and complexity of the equipment employed for that purpose.

1 - 5 . (canceled)  
     
     
         6 . A method for applying a powdered resin coating onto fasteners comprising: 
 generating an airborne powdered resin stream from a nozzle;    passing a plurality of fasteners through said resin stream to apply said coating;    collecting powdered resin overspray from said resin stream by means of a vacuum nozzle;    introducing new powdered resin into said vacuum nozzle thereby forming a new and recycled resin mixture; and    collecting the resin mixture and transferring the resin mixture to said nozzle.    
     
     
         7 . The powder application method of  claim 6  wherein the resin mixture formed in the vacuum nozzle is recirculated to the nozzle in a substantially enclosed powder handling system.  
     
     
         8 . The powder application method of  claim 7  wherein said powder handling system includes a bag collector and wherein a plurality of air pulses are applied to the collector to discharge the resin mixture from the collector.  
     
     
         9 . The powder transfer mechanism of  claim 8  wherein the resin mixture discharged from the collector is received by a recycled resin transfer mechanism and then transferred to the nozzle.