Line-of-sight coating fixture and apparatus

Abstract

An embodiment of a line-of-sight coating fixture includes a support structure, a spindle, and a shadow structure. The support structure includes a plurality of compartments disposed below a platter, each compartment having an opening on a periphery of the support structure. Each compartment is adapted to receive and secure a base of a workpiece such that a body of each workpiece to be coated is disposed about a periphery of the support structure and extends above the platter. The spindle is disposed through a center of the platter or support structure for rotating the workpieces thereabout. The shadow structure is disposed about the spindle, inside of the periphery, the shadow structure sized and adapted to shield a portion of each workpiece from line-of-sight coating material.

1 . A line-of-sight coating fixture comprising:
 a support structure including a plurality of compartments disposed below a platter, each compartment having an opening on a periphery of the support structure, and each compartment adapted to receive and secure a base of a workpiece such that a body of each workpiece to be coated is disposed about a periphery of the support structure and extends above the platter;   a spindle disposed through a center of the platter or support structure for rotating the workpieces thereabout; and   a shadow structure disposed about the spindle, inside of the periphery, the shadow structure sized and adapted to shield a portion of each workpiece from line-of-sight coating material.   
     
     
         2 . The fixture of  claim 1  wherein the compartment is defined by an enclosure including at least one hinged door. 
     
     
         3 . The fixture of  claim 1 , wherein the plurality of workpieces include a plurality of rotor blades. 
     
     
         4 . The fixture of  claim 3 , wherein each compartment is adapted to receive and secure a root of a workpiece such that an airfoil portion of each workpiece to be coated is disposed about a periphery of the support structure and extends above the platter. 
     
     
         5 . The fixture of  claim 4 , wherein the platter is shaped to conform to a platform of each of the plurality of rotor blades, such that an upper surface of the platform is exposed and a lower surface of the platform is shielded. 
     
     
         6 . The fixture of  claim 3 , further comprising at least one removable insert adapted to conform to the root of each workpiece. 
     
     
         7 . The fixture of  claim 6 , wherein the at least one removable insert includes a first insert and a second insert adapted to conform to first and second sides of a dovetail root. 
     
     
         8 . The fixture of  claim 3 , wherein a span of the plurality of airfoils are aligned with a rotational axis of the fixture/spindle. 
     
     
         9 . The fixture of  claim 3 , wherein the shadow structure includes a plurality of shadow bars including a plurality of shadow walls defining a recess for separately covering each trailing edge of the plurality of airfoils. 
     
     
         10 . The fixture of  claim 9 , wherein the recesses defined by the plurality of shadow bars also cover a window or outlet portion of the pressure surface adjacent to the trailing edge. 
     
     
         11 . A line-of-sight coating apparatus comprising:
 a coating chamber defined by at least one wall;   a line-of-sight coating source disposed along the at least one wall and directed toward a plurality of fixtures according to  claim 1 .   
     
     
         12 . The apparatus of  claim 11 , wherein plurality of fixtures are arranged linearly or longitudinally opposed to the coating source. 
     
     
         13 . The apparatus of  claim 11 , wherein the compartments are operative to shield at least the base of each workpiece from the line-of-sight coating material. 
     
     
         14 . The apparatus of  claim 11 , wherein the coating source includes an EB-PVD coating source. 
     
     
         15 . The apparatus of  claim 11 , wherein the plurality of workpieces include a plurality of rotor blades, and wherein the plurality of compartments each include at least one removable insert adapted to receive and secure a root portion of a rotor blade such that a platform portion and an airfoil portion extend above the platform in a first orientation. 
     
     
         16 . The apparatus of  claim 15 , wherein the platter is shaped to conform to a platform contour of each of the plurality of rotor blades, such that an upper surface of the platform is exposed to the line-of-sight coating source and a lower surface of the platform is shielded from the line-of-sight coating source. 
     
     
         17 . The apparatus of  claim 15 , wherein the shadow structure includes a plurality of shadow bars including at least one wall defining a recess for separately covering each trailing edge and a window or outlet portion of the pressure surface adjacent to the trailing edge of the plurality of airfoils. 
     
     
         18 . A method of line-of-sight coating comprising:
 securing a base of a workpiece to a support structure including a plurality of compartments disposed below a platter, each compartment having an opening on a periphery of the support structure for receiving each workpiece base, such that a body of each workpiece to be coated is disposed about a periphery of the support structure and extends above the platter;   rotating the workpieces about a spindle disposed through a center of the platter or support structure; and   shielding a portion of each workpiece from a stream of line-of-sight coating material via a shadow structure disposed about the spindle, inside of the periphery.   
     
     
         19 . The method of  claim 18 , wherein the plurality of workpieces include a plurality of rotor blades; and wherein each compartment is adapted to receive and secure a root of each rotor blade workpiece such that an airfoil portion of each rotor blade workpiece to be coated is disposed about a periphery of the support structure and extends above the platter. 
     
     
         20 . The method of  claim 18 , wherein the platter is shaped to conform to a platform of each of the plurality of rotor blades, such that an upper surface of the platform is exposed and a lower surface of the platform is shielded.