Method of making convoluted coated braided hose assembly

Abstract

A seamless convoluted hose assembly. The assembly includes: a tubular inner liner having an outer surface, an inner surface, and an inner liner wall therebetween which defines a passageway. The assembly further includes a helical coil or a plurality of annular loops which produce convolutions in the outer surface of the tubular liner when the tubular inner liner is forced through the helical coil or plurality of loops under heat and pressure.

The invention claimed is: 
     
         1 . A method of forming a seamless convoluted hose assembly including the steps of:
 applying radially outward pressure and heat to an inner surface of a meltable, expandable tubular inner liner; and   restricting outward expansion of a first plurality of segments of an inner liner wall of the tubular inner liner while allowing outward expansion of a second plurality of segments of the inner liner wall of the tubular inner liner, each member of the first plurality of segments being adjacent to a member of the second plurality of segments, the first plurality of segments thereby becoming the valleys of a plurality of convolutions, and the second plurality of segments becoming the peaks of the plurality of convolutions.   
     
     
         2 . A method as set forth in  claim 1  wherein said step of applying radially outward pressure and heat further comprises pressurizing the tubular inner liner with inert gas and applying heat sufficient to expand the walls of the tubular inner liner. 
     
     
         3 . A method as set forth in  claim 1  wherein said step of restricting outward expansion of a first plurality of segments of an inner liner wall of the tubular inner liner further includes the step of positioning convolution producing means about the tubular inner liner. 
     
     
         4 . A method as set forth in  claim 1  wherein positioning convolution producing means about the tubular inner liner further includes the step of positioning convolution producing means exterior to the outer surface of the tubular inner liner. 
     
     
         5 . A method as set forth in  claim 1  wherein positioning convolution producing means about the tubular inner liner further includes the step of positioning convolution producing means interior to the inner surface of the tubular inner liner. 
     
     
         6 . A method as set forth in  claim 1  wherein positioning convolution producing means about the tubular inner liner further includes positioning a helical coil about the tubular inner liner. 
     
     
         7 . A method as set forth in  claim 1  wherein positioning convolution producing means about the tubular inner liner further includes positioning a plurality of annular loops about the tubular inner liner. 
     
     
         8 . A method as set forth in  claim 3  wherein convolution producing means comprises glass fiber. 
     
     
         9 . A method as set forth in  claim 3  wherein convolution producing means comprises metallic wire. 
     
     
         10 . A method as set forth in  claim 1  further including the step of limiting the outward expansion of the plurality of convolutions. 
     
     
         11 . A method as set forth in  claim 10  wherein limiting the outward expansion of the plurality of convolutions further includes the step of positioning an outer reinforcing layer exterior to the outer surface of the tubular inner liner and to convolution producing means. 
     
     
         12 . A method as set forth in  claim 11  wherein positioning an outer reinforcing layer further comprises positioning braided glass fiber 
     
     
         13 . A method as set forth in  claim 11  wherein positioning an outer reinforcing layer further comprises positioning braided wire. 
     
     
         14 . A method as set forth in  claim 11  wherein positioning an outer reinforcing layer exterior to the outer surface of the tubular inner liner and to convolution producing means further includes bonding together the outer reinforcing layer, the outer surface of the tubular liner and convolution producing means by coating with an outer coating. 
     
     
         15 . A method as set forth in  claim 14  wherein coating with an outer coating further includes coating the outer reinforcing layer, the outer surface of the tubular liner and convolution producing means with a fluorocarbon polymer dispersion, and sintering to cure the fluorocarbon polymer dispersion into a fluorocarbon polymer coating.