Pre-tensioned article and method of making
A pre-tensioned article and method of making an article of footwear involving pre-tensioning a sole structure during manufacturing. In some embodiments, the sole structure may include a plurality of apertures that provide an auxetic effect. In further embodiments, the upper may also be pre-tensioned in a similar manner as the sole structure.
1. An article of footwear, comprising:
an upper;
a sole structure attached to the upper;
wherein each of the upper and the sole structure defines a plurality of apertures arranged in an auxetic configuration;
wherein, when worn by a user, the sole structure is configured to expand auxetically, and the upper is also configured to expand auxetically;
wherein the article of footwear has an unworn article state and a worn article state;
wherein the article of footwear transitions from the unworn article state to the worn article state in response to the user wearing the article of footwear;
wherein the plurality of apertures of the upper and the sole structure are closed when the article of footwear is in the unworn article state; and
wherein the plurality of apertures of the upper and the sole structure are open when the article of footwear is in the worn article state.
2. The article of footwear according to claim 1 , wherein the sole structure has a first thickness when the article of footwear is in the unworn article state, the sole structure has a second thickness when the sole structure is subjected to a lateral force, and the first thickness and the second thickness are substantially similar.
3. The article of footwear according to claim 1 , wherein, when the upper and the sole structure are subjected to a force of a same magnitude, both the upper and the sole structure are configured to expand at a substantially similar rate.
4. The article of footwear according to claim 1 , wherein when the upper and the sole structure are subjected to a force of a same magnitude, the upper expands at a greater rate than that of the sole structure.
5. The article of footwear according to claim 1 , wherein the sole structure comprises foam.
6. The article of footwear according to claim 1 , wherein the plurality of apertures of the sole structure are substantially a same size as the plurality of apertures of the upper while the article of footwear is in the unworn article state.
7. The article of footwear according to claim 1 , wherein the upper has an unworn upper state and a worn upper state, the upper transitions from the unworn upper state to the worn upper state in response to the user wearing the article of footwear, while the sole structure is is in a worn sole state, the plurality of apertures of the sole structure are larger than the plurality of apertures of the upper while the upper is in the worn upper state.
8. The article of footwear according to claim 1 , wherein the sole structure includes a forefoot region, a heel region, and a midfoot region disposed between the heel region and the forefoot region, the plurality of apertures of the sole structure in the heel region are fully closed, the plurality of apertures of the sole structure in the forefoot region are fully extended, and the plurality of apertures of the sole structure in the midfoot region are partially closed.
9. The article of footwear according to claim 1 , wherein the upper has a first thickness, the sole structure has a second thickness, and the first thickness is less than the second thickness.
10. The article of footwear according to claim 1 , wherein the plurality of apertures of the upper are larger than the plurality of apertures of the sole structure.
11. The article of footwear according to claim 1 , wherein the plurality of apertures of the upper and the sole structure expand at a substantially similar rate when subjected to a substantially similar magnitude of force.