Shock absorbing fabric structures
Fabric structures having elongation yarns and ground yarns that form a sheath are provided, with the structure having two connection segments and at least one expansion segment in between the connection segments. Heat treatment of the one or more expansion segments shrinks the length of the elongation yarns during manufacture. A tensile load applied to the fabric structure stretches the elongation yarns and unfolds the gathered sheath. The elongation yarns absorb energy as the fabric structure elongates. In some embodiments, the fabric structure has more than one expansion segment so that the deployment force of the structure is not constant. In some embodiments, the fabric structure includes a band in some portions.
1. A fabric structure comprising:
a plurality of ground yarns that form a sheath;
a plurality of elongation yarns, wherein the plurality of elongation yarns comprise partially oriented yarns; and
a band capable of elongation,
wherein the ground yarns, the elongation yarns, and the band extend in a substantially warp direction in the fabric structure and wherein the band is woven so that it is loose inside a portion of the fabric structure,
wherein the sheath surrounds the plurality of elongation yarns, and
wherein the sheath surrounds the band in at least a portion of the fabric structure, and wherein the band is outside the fabric structure in at least another portion of the fabric structure.
2. The fabric structure of claim 1 , wherein the band includes elastic.
3. The fabric structure of claim 1 , wherein the band has a breaking strength that is less than a breaking strength of the sheath.
4. The fabric structure of claim 1 , wherein the band prevents the fabric structure from extending when subjected to a relatively small force.
5. A fabric structure comprising:
a plurality of ground yarns that form a sheath;
a plurality of elongation yarns, wherein the plurality of elongation yarns comprise partially oriented yarns; and
a band,
wherein the ground yarns, the elongation yarns, and the band extend in a substantially warp direction in the fabric structure and wherein the band is woven loosely inside the fabric structure,
wherein the sheath surrounds the plurality of elongation yarns,
wherein the sheath surrounds the band in at least a portion of the fabric structure, and wherein the band is outside the fabric structure in at least another portion of the fabric structure, and
wherein the band causes the fabric structure to constrict so that a length of the fabric structure is less than it would be if the band were not present.
6. The fabric structure of claim 5 , wherein the band comprises elastic.