US4249319A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Heat insulating insert for footwear
Assignee: Individual
•
Filing: 1980-01-18
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Granted: 1981-02-10
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Expires: 2000-01-18
Abstract
Abstract A heat insulating insert for a footwear which comprises a base sheet having a shape conforming with that of the sole of an average human foot and a toe cover at the toe portion of the base sheet for embracing the toe of the human foot. Porous bags containing exothermic agent therein are provided on the inner surface of the top of the toe cover and the toe portion of the base sheet in opposing and spaced relationship to the exothermic agent bag on the inner surface of the top of the toe cover and also in a portion of the base sheet corresponding to the plantar arch of the human foot. The exothermic agent performs exothermic reaction with the open air.
Inventors
- 👤 Yoshiyasu Yoshida
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-30 07:42
CPC Classifications
A; A61; A61F; A61F7/00; A61F7/02; A61F7/03; A43; A43B; A43B7/00; A43B7/14; A43B7/1405; A43B7/1455; A43B7/146; F; F24; F24V; F24V30/00; A61F2007/0001; A61F2007/0039; A61F2007/0046; A61F2007/0047
Claims Analysis
Total Claims: 9
Claim 1
Independent Claim
139 words
A heat insulating insert for a footwear comprising a main body which includes a base sheet having a shape substantially conforming with the shape of the sole of a human foot and a toe cover at the toe-shaped end of said base sheet corresponding to the toe of said human foot; and permeable bags positioned in said toe portion and a portion of said base sheet corresponding to the plantar arch of said human foot and on the inner surface of said toe cover and each containing exothermic agent which performs exothermic reaction with the open air upon contacting the open air, said permeable bags at said toe shaped-end of the base sheet and on the inner surface of said toe cover being in opposing and spaced relationship to each other to embrace said toe of the human foot.
Claim 2
Dependent Claim
139 words
A heat insulating insert for a footwear comprising a main body which includes a base sheet having a shape substantially conforming with the shape of the sole of a human foot and a toe cover at the toe-shaped end of said base sheet corresponding to the toe of said human foot; and permeable bags positioned in said toe portion and a portion of said base sheet corresponding to the plantar arch of said human foot and on the inner surface of said toe cover and each containing exothermic agent which performs exothermic reaction with the open air upon contacting the open air, said permeable bags at said toe shaped-end of the base sheet and on the inner surface of said toe cover being in opposing and spaced relationship to each other to embrace said toe of the human foot.
Claim 3
Dependent Claim
48 words
The heat insulating insert for a footwear as set forth in claim 1, in which said base sheet and cover sheet are each formed of a sheet of leather, felt or synthetic rubber or a laminated structure of one or more of said leather, felt and synthetic rubber.
Claim 4
Dependent Claim
24 words
The heat insulating insert for a footwear as set forth in claim 1, in which said base sheet is formed of a non-woven fabrics.
Claim 5
Dependent Claim
50 words
The heat insulating insert for a footwear as set forth in claim 1, in which when said base sheet and toe cover are each formed of leather material, said leather material is provided with a number of small holes to provide a permeability to the base sheet and toe cover.
Claim 6
Dependent Claim
42 words
The heat insulating insert for a footwear as set forth in claim 1, in which said exothermic agent comprises a mixture of powdery or particle metal powder and oxidizing catalyst and performs exothermic reaction with the open air upon contacting the air.
Claim 7
Dependent Claim
23 words
The heat insulating insert for a footwear as set forth in claim 5, in which said powdery or particle metal is iron powder.
Claim 8
Dependent Claim
59 words
The heat insulating insert for a footwear as set forth in claim 1, in which said permeable bags for exothermic agent each has a semi-circular shape and sewn to said base sheet and toe cover except for the straight edge of the bag to provide an opening through which said exothermic agent is inserted into the associated permeable bag.
Claim 9
Dependent Claim
36 words
The heat insulating insert for a footwear as set forth in claim 1, in which said permeable bags are each formed of a coarsely woven fabric or a sheet provided with a number of small holes.
References Cited (Backward Citations)
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1984-02-10 | 1984-08-11 | 1985-02-10 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1988-02-10 | 1988-08-11 | 1989-02-10 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1992-02-10 | 1992-08-11 | 1993-02-10 | $7700.00 | Window Closed / Lapsed |