Source: {"pile_set_name": "USPTO Backgrounds"}

1. Field of the Invention
This invention relates to cushioned insoles for shoes and other footwear. Such cushions are worn for orthopedic purposes or simply for comfort.
2. Prior Art
The closest prior art known to applicant is Zente U.S. Pat. No. 3,922,801 issued Dec. 2, 1975. Additional prior art is cited in the Zente Patent, namely: Pat. Nos. 532,429, 1,069,001, 1,193,608, 1,148,376, 1,517,171, 2,477,588, 2,546,296, 2,549,343, 2,641,066 and 3,724,106.
The Zente Patent shows a plurality of non-communicating compartments formed between a pair of plastic laminae, each of said compartments containing a separate liquid-filled ampule or bag. In the illustrated form of the Zente insole there are eleven compartments and eleven liquid-filled ampules confined within said compartments.
The procedure for making the Zente insole is complicated and costly and the result is less than optimum since the desired cushion effect is diminished by the presence of multiple plastic layers between the liquid and the foot.