Patent ID: 7811629
Filing Date: 2010-10-12
Classification: B05B,B05C,B05D,Y02P

Abstract:
1. A method of applying a plastic resin patch onto a screw comprising the steps of: (a) pre-determining a desired patch geometry on a screw; (b) selecting a nozzle insert dimensioned to provide the desired patch geometry, wherein the nozzle insert comprises two semi-circular pegs fitted inside a powder ejection orifice of a patch application system such that a gap exists between the two semi-circular pegs, wherein the gap narrows a vertical dimension of the powder ejection orifice; (c) adjusting a distance between the nozzle insert and the screw to create a lead-in; (d) selecting and adding an amount of a powder required to produce the desired patch geometry while minimizing waste; (e) selecting a duration of a pulse of air and an air pressure to pulse onto the powder; (f) heating the screw to a temperature sufficient to melt the powder; (g) pulsing air at the duration and the air pressure through the powder to cause the powder to eject onto the screw and melt onto the screw; (h) quenching the powder melted onto the screw to solidify the powder; (i) comparing a resulting patch geometry with the desired patch geometry; (j) adjusting at least one parameter selected from the group consisting of the nozzle insert, the distance between the nozzle insert and the screw, the amount of the powder, the duration of the pulse of air, and the air pressure; and (k) repeating steps (b) through (j) until the desired patch geometry is achieved.