Shoe with an improved midsole
US5343639A · kind A · utility
Assignee
Inventors
Key dates
| Filing date | Oct 18, 1993 |
| Grant date | Sep 6, 1994 |
| Priority date | — |
| Expiry date | Oct 18, 2013 |
Classification
- Technology area (CPC A)Human Necessities
- CPC primaryA43B13/20
- WIPO fieldOther consumer goods
- WIPO sectorOther fields
Abstract
The invention is directed to a midsole for a shoe including one or more foam columns disposed between an upper and a lower plate. One or more elastomeric foam elements are disposed between the upper and lower plates. The foam elements are made of a material such as microcellular polyurethane-elastomer based on a polyester-alcohol and naphthalene-disocyanate (NDI). In one embodiment, the foam elements have the shape of hollow cylindrical columns, and may include grooves formed on the exterior surface. One or more elastic rings are disposed about the columns and are removably disposable in the grooves, allowing the stiffness of the columns to be adjusted. In a further embodiment, inflatable gas bladders are disposed in the hollow regions. The heights of the gas bladders may be less than the heights of the columns such that when the midsole is compressed, the wearer experiences a first stiffness corresponding to compression of the columns alone, and a second stiffness corresponding to compression of both the columns and the bladders. Alternatively, the bladders may be inflated so as to cause the columns to be stretched, even when no load is applied. Since the level of inflation of the…
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.