Resilient bladder for use in footwear, footwear and method of making the bladder

摘要

The present invention includes a method for forming a resilient bladder structure for use in the sole of footwear. The method comprises the steps of forming a shell from a flexible material (28) to have a floor and a perimeter sidewall extending from the floor; placing a core (24), having spaced apart outer surfaces connected together by a plurality of connecting members, into the shell within the area bounded by the sidewalls; enclosing the shell and core with a covering sheet (26); bonding the floor of the shell to one outer surface of the core and the covering sheet to the other outer surface of the core by applying pressure and heat to the shell-core-covering sheet assembly to compress the core during the bonding step; preventing bonding of the sidewall to the covering sheet during the compression of the core; and bonding the covering sheet to an outer edge of the perimeter sidewall of the shell to form a sealed bladder structure; and placing fluid into the interior of the bladder so that the plurality of connecting members are placed under tension. The present invention is also directed to a bladder for use as a cushioning element and footwear incorporating the bladder. The enclosed core is formed of spaced apart first and second fabric layers (34, 36) connected together by a plurality of connecting yarns (38). The shell is formed of see-through plastic material whereby the connecting yarns are visible through the sidewall (32). The plurality of connecting yams preferably are arranged in bands (44) with gaps (46) devoid of connecting yarns between adjacent bands, and the ends of the bands and the gaps are visible through the sidewall.