Three dimensional braid

Abstract

A three dimensional braid includes a plurality of first plaits adjacent one another oriented in a first direction and a plurality of second plaits adjacent one another oriented in a transverse second direction intertwined forming a braid with each first plait intersecting each of the plurality of second plaits in succession. Each first plait includes a first group of tows and a second group of tows, each of the tows in the first group of tows corresponding to one of the tows in the second group of tows in pairs of first plait tows. Each second plait includes a plurality of tows. For each first plait, one of the first plait pairs crosses over a subset of second plait tows at each intersection of the first plait and successive second plaits forming a series of braid points along the first plait.

What is claimed is: 
     
         1 . A braided material comprising
 a plurality of first plaits adjacent one another oriented in a first direction having a positive angle e from a reference braid direction;   a plurality of second plaits adjacent one another oriented in a second direction transverse to the first direction having a negative angle β from the reference braid direction, the plurality of first plaits intertwined with the plurality of second plaits forming a braid;   each first plait comprising
 a first group of tows having X number of tows; 
 a second group of tows having X number of tows; 
 each of the tows in the first group of tows corresponding to one of the tows in the second group of tows in X number of pairs of first plait tows; 
   each second plait comprising
 a third group of tows having Y number of tows; 
 a fourth group of tows having Y number of tows; 
 each of the tows the third group of tows corresponding to one of the tows in the fourth group of tows in Y number of pairs of second plait tows; 
   each first plait intersecting each of the plurality of second plaits in succession;   for each first plait, one of the first plait pairs crossing over a subset of second plait tows at each intersection of said first plait and successive second plaits forming a series of X braid points along the first plait.   
     
     
         2 . The braided material according to  claim 1 , where
 a portion of the tows of each first plait and each second plait forms an outer subset and the remainder of the tows of the plait forms an inner subset, where   each of the pairs of first plait tows includes one tow in the inner subset and one tow in the outer subset, and where   at each of the first plait pair crossings the tow of the pair in the inner subset switching to the outer subset and the other tow of the pair switching to the inner subset.   
     
     
         3 . The braided material according to  claim 2 , each of the first plait pair crossings being over the outer subset of the second plait tows at each intersection of said first plait and the successive second plait. 
     
     
         4 . The braided material according to  claim 1 , at each intersection of each first plait with successive second plaits, the subset of second plait tows being Y number of tows selected from the third group, the fourth group, or both. 
     
     
         5 . The braided material according to  claim 1 , further comprising
 each second plait intersecting each of the plurality of first plaits in succession;   for each second plait, one of the second plait pairs crossing over a subset of first plait tows at each intersection of said first plait and the successive first plait forming a series of Y braid points along the second plait.   
     
     
         6 . The braided material according to  claim 5 , where
 a portion of the tows of each first plait and each second plait forms an outer subset and the remainder of the tows of the plait forms an inner subset, where   each of the pairs of second plait tows includes one tow in the inner subset and one tow in the outer subset, and where   at each of the second plait pair crossings the tow of the pair in the inner subset switching to the outer subset and the other tow of the pair switching to the inner subset,   
     
     
         7 . The braided material according to  claim 6 , each of the second plait pair crossings being over the inner subset of the first plait tows at each intersection of said second plait and the successive first plait. 
     
     
         8 . The braided material according to  claim 5 , at each intersection of each second plait with successive first plaits, the subset of first plait tows being X number of tows selected from the first group, the second group, or both. 
     
     
         9 . The braided material according to  claim 1 , where θ is approximately 60 degrees and β is approximately 60 degrees. 
     
     
         10 . The braided material according to  claim 1  where θ is approximately 45 degrees and β is approximately 45 degrees. 
     
     
         11 . The braided material according to  claim 1 , where θ is approximately 60 degrees and β is approximately 45 degrees. 
     
     
         12 . The braided material according to  claim 1 , where X is selected from a range from 2 to 6 and Y is selected from a range from 2 to 6. 
     
     
         13 . The braided material according to  claim 1 , where X is 3 and Y is 3. 
     
     
         14 . The braided material according to  claim 1 , where X is 4 and Y is 4. 
     
     
         15 . The braided material according to  claim 1 , where X is 3 and Y is 4. 
     
     
         16 . The braided material according to  claim 1 , where the plurality of first plaits is between 3 and 120 in number. 
     
     
         17 . The braided material according to  claim 1 , where the plurality of first plaits is 12 in number. 
     
     
         18 . The braided material according to  claim 1 , where the plurality of second plaits is between 3 and 120 in number. 
     
     
         19 . The braided material according to  claim 1 , where the,plurality of second plaits is 12 in number. 
     
     
         20 . The braided material according to  claim 1 , further comprising one or more axial tows along the reference braid direction.