Method and apparatus for maintaining filaments in position in a filament winding process

Abstract

A method for maintaining filaments in position when manufacturing composite parts through a filament winding process. In its most basic form the method includes a first step of applying resin impregnated filament ( 16 ) onto an elongate mandrel ( 12 ). A second step is involved of winding yarn ( 32 ) onto the elongate mandrel ( 12 ) overlying the resin impregnated filament ( 16 ), to maintain the resin impregnated filament ( 16 ) in position and under tension.

1 . A method for maintaining filaments in position when manufacturing composite parts through a filament winding process, comprising the steps of: 
 applying resin impregnated filament ( 16 ) onto an elongate mandrel ( 12 ); and    winding yarn ( 32 ) onto the elongate mandrel ( 12 ) overlying the resin impregnated filament ( 16 ), to maintain the resin impregnated filament ( 16 ) in position and under tension.    
   
   
       2 . The method as defined in  claim 1 , the steps being sequentially repeated by applying alternating layers of resin impregnated filament ( 16 ) followed by yarn ( 32 ) to maintain each layer of resin impregnated filament ( 16 ) in position and under tension.  
   
   
       3 . The method as defined in  claim 1 , collars ( 24 ) with projecting spikes ( 26 ) being positioned in spaced relation on the mandrel ( 12 ) to assist in maintaining filament positioning and spacing, the filaments ( 16 ) extending between the respective collars ( 24 ) with filament spacing being maintained by segregating the filaments ( 16 ) with the projecting spikes ( 26 ).  
   
   
       4 . The method as defined in  claim 1 , slotted grooves being positioned in spaced relation on the mandrel ( 12 ) to assist in maintaining filament positioning and spacing.  
   
   
       5 . The method as defined in  claim 1 , including the step of wrapping a circumferential wrap of filament ( 16 ) around the mandrel ( 12 ) at the end of each pass in order to anchor the filament ( 16 ).  
   
   
       6 . The method as defined in  claim 1 , at least one ring ( 28 ) being provided which is co-axial to and encircles the mandrel ( 12 ), the yarn ( 32 ) being positioned on a spool ( 30 ), which is mounted on the ring ( 28 ), the spool ( 30 ) orbiting the mandrel ( 12 ) to apply yarn ( 32 ) circumferentially to the mandrel ( 12 ).  
   
   
       7 . The method as defined in  claim 6 , more than one ring ( 28 ) being provided.  
   
   
       8 . The method as defined in  claim 6 , the spool ( 30 ) being fixed in position on the ring ( 28 ) and the ring ( 28 ) rotating about its axis.  
   
   
       9 . The method as defined in  claim 6 , guides ( 33 ) being provided to guide the path of the yarn ( 32 ) as it leaves the spool ( 30 ).  
   
   
       10 . The method as defined in  claim 9 , the guides ( 33 ) being supported by a support-arm.  
   
   
       11 . The method as defined in  claim 1 , the orientation of the filament being controlled by selectively rotating the mandrel ( 12 ).  
   
   
       12 . The method as defined in  claim 1 , the mandrel ( 12 ) being moved axially.  
   
   
       13 . The method as defined in  claim 6 , the at least one ring ( 28 ) being moved axially along the mandrel ( 12 ).  
   
   
       14 . The method as defined in  claim 1 , wherein at least one impregnation box ( 14 ) is provided to impregnate filament ( 16 ) with resin.  
   
   
       15 . The method as defined in  claim 1 , wherein guide rollers ( 20 ) are provided to control application of the filament ( 16 ).