Shock absorbing lanyards

Abstract

A shock absorbing lanyard is a one-piece webbing. The shock absorbing lanyard has a tubular-shaped high strength outer sheath and a high elongation member inside of the outer sheath. The outer sheath and the high elongation member are secured together at spaced apart connection locations and the high elongation member is generally not secured to the outer sheath between the connection locations. Heat treatment shrinks the length of the high elongation member. The outer sheath does not substantially shrink from the heat treatment relative to the high elongation member and gathers together in an accordion-like arrangement. A tensile load applied to the lanyard stretches the high elongation member and unfolds the gathered outer sheath. The high strength outer sheath supports the tensile load when completely unfolded while the high elongation member absorbs energy as it stretches or elongates.

1 . A lanyard, comprising: 
 a load-supporting outer sheath;    a heat shrunken elongation member extending along an inside of the outer sheath; and    first and second spaced apart connection locations in which the elongation member is secured to the load-supporting outer sheath;    wherein, the elongation member has an un-stretched heat shrunken length between the first and second connection locations substantially shorter than a length of the load-supporting outer sheath between the first and second connection locations.    
   
   
       2 . The lanyard of  claim 1 , further comprising a binder yarn and wherein the elongation member is secured to the load-supporting outer sheath by the binder yarn.  
   
   
       3 . The lanyard of  claim 1 , wherein the elongation member has elongation yarns and is secured to the load-supporting outer sheath by the elongation yarns and yarns of the load-supporting outer sheath being interlaced together.  
   
   
       4 . The lanyard of  claim 3 , further comprising a binder yarn interlaced with the elongation yarns and the yarns of the load-supporting outer sheath.  
   
   
       5 . The lanyard of  claim 1 , wherein the elongation member is secured to the load-supporting outer sheath by stitching.  
   
   
       6 . The lanyard of  claim 1 , wherein at least one of the elongation member and the load-supporting outer sheath is selected from the group consisting of woven materials, braided materials, knitted materials, non-woven materials, and combinations thereof.  
   
   
       7 . The lanyard of  claim 1 , wherein a portion of the lanyard has a portion of the elongation member extending to an exterior surface of the load-supporting outer sheath.  
   
   
       8 . A lanyard, comprising: 
 a tubular-shaped webbing;    heat-shrunk elongation yarns inside of the tubular-shaped webbing;    first and second spaced apart binder portions in which the heat-shrunk elongation yarns are secured to the tubular-shaped webbing; and    an expansion portion between the first and second binder portions in which the heat shrunk elongation yarns are extensible relative to the tubular-shaped webbing and the tubular-shaped webbing is in a gathered position.    
   
   
       9 . The lanyard of  claim 8 , further comprising a binder yarn and wherein the heat-shrunk elongation yarns are secured to the tubular-shaped webbing by the binder yarn.  
   
   
       10 . The lanyard of  claim 8 , wherein the heat-shrunk elongation yarns are secured to the tubular-shaped webbing by the heat-shrunk elongation yarns and yarns of the tubular-shaped webbing being interlaced together.  
   
   
       11 . The lanyard of  claim 10 , further comprising a binder yarn interlaced with the heat-shrunk elongation yarns and the yarns of the tubular-shaped webbing.  
   
   
       12 . The lanyard of  claim 8 , wherein the heat-shrunk elongation yarns are secured to the tubular-shaped webbing by stitching.  
   
   
       13 . The lanyard of  claim 8 , wherein at least one of the heat-shrunk elongation yarns and the tubular-shaped webbing is selected from the group consisting of woven materials, braided materials, knitted materials, non-woven materials, and combinations thereof.  
   
   
       14 . The lanyard of  claim 8 , further comprising another binder portion in which the heat-shrunk elongation yarns are secured to the tubular-shaped webbing with a different structure than the first and second binder portions.  
   
   
       15 . The lanyard of  claim 8 , further comprising a hardware attachment portion having a portion of the heat-shrunk elongation yarns extending to an outside of the tubular-shaped webbing.  
   
   
       16 . A method of making a lanyard, comprising the steps of: 
 forming an outer sheath and elongation yarns within the outer sheath;    securing the elongation yarns to the outer sheath at connection locations; and    reducing a length of the elongation yarns between a pair of the connection locations.    
   
   
       17 . The method of making a lanyard of  claim 16 , wherein the reducing step further comprises heat treating at least the elongation yarns.  
   
   
       18 . The method of making a lanyard of  claim 16 , wherein the securing step further comprises interweaving a binder yarn with the elongation yarns and yarns of the outer sheath.  
   
   
       19 . The method of making a lanyard of  claim 16 , wherein the securing step further comprises interweaving the elongation yarns and yarns of the outer sheath.  
   
   
       20 . The method of making a lanyard of  claim 19 , wherein the securing step further comprises interweaving a binder yarn with the elongation yarns and the yarns of the outer sheath.  
   
   
       21 . The method of making a lanyard of  claim 16 , wherein the securing step further comprises sewing the elongation yarns and the yarns of the outer sheath together.  
   
   
       22 . The method of making a lanyard of  claim 16 , wherein the reducing step does not substantially reduce a length of the outer sheath between the pair of connection locations.