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US4201218A Expired / Lapsed US ⏱️ 0.0 years remaining

Therapeutic heat application

Assignee: Individual
•
Filing: 1978-12-22
•
Granted: 1980-05-06
•
Expires: 1998-12-22
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Abstract

Abstract A portable heating device includes an envelope made by heat-sealing the edges of two flexible polymeric films, and a heat source within the envelope including, in one embodiment, a ribbon of conductive resistance heating element material folded into a generally sinuous, flat pattern within the envelope, and a nonconductive liquid such as silicone oil in the envelope and surrounding the heating element. In a second embodiment, the heat source is a semiconductor device. The envelope is carried by a strap or the like to hold the envelope next to a selected portion of the body for localized heating thereof. The heating element in the first embodiment is electrically connected to a power source such as batteries, and, in the second embodiment, the semiconductor device is connected to a control circuit which is connected to batteries.

Inventors

  • 👤 Henry L. Feldman
  • 👤 Philip G. Berman
  • 👤 William L. Washburn

Bibliographic Details

Application Number —
Jurisdiction US
Data Source google_patents
Last Synchronized 2026-10-24 05:58
CPC Classifications
A; A61; A61F; A61F7/00; A61F7/007; A61F2007/0001

Claims Analysis

Total Claims: 7
Claim 1
Independent Claim 138 words
A portable therapeutic heating device for localized heating of a body part comprising the combination of first and second flexible thermally conductive and electrically nonconductive sheets of substantially liquid impermeable material bonded to each other along their margins to form a sealed envelope; a thermally conductive and electrically nonconductive liquid contained in and substantially filling said envelope; an electric heat source comprising a semiconductor electron valve immersed in said liquid; bandage means attached to said envelope for holding said envelope in contiguous heat-transferring relationship with a selected portion of a body; a portable source of electrical energy; and control circuit means for interconnecting said source of energy and said valve, whereby said valve is energizied by current from said source and the heat generated thereby is transferred to said liquid and to said selected portion of the body.
Claim 2
Dependent Claim 138 words
A portable therapeutic heating device for localized heating of a body part comprising the combination of first and second flexible thermally conductive and electrically nonconductive sheets of substantially liquid impermeable material bonded to each other along their margins to form a sealed envelope; a thermally conductive and electrically nonconductive liquid contained in and substantially filling said envelope; an electric heat source comprising a semiconductor electron valve immersed in said liquid; bandage means attached to said envelope for holding said envelope in contiguous heat-transferring relationship with a selected portion of a body; a portable source of electrical energy; and control circuit means for interconnecting said source of energy and said valve, whereby said valve is energizied by current from said source and the heat generated thereby is transferred to said liquid and to said selected portion of the body.
Claim 3
Dependent Claim 12 words
A device according to claim 1 wherein said valve is a transistor.
Claim 4
Dependent Claim 59 words
A device according to claim 2 wherein said control circuit means includes an astable multivibrator connected to said transistor to repetitively and periodically render said transistor conductive; and a timing circuit including a positive temperature coefficient resistance element connected to said multivibrator to control the repetition rate thereof, said resistance element being in heat transfer relationship with said fluid.
Claim 5
Dependent Claim 12 words
A device according to claim 3 wherein said fluid is silicone oil.
Claim 6
Dependent Claim 136 words
A portable therapeutic heating device for localized heating of an article comprising the combination of first and second flexible thermally conductive and electrically nonconductive sheets of substantially liquid impermeable material bonded to each other along their margins to form a sealed envelope; a thermally conductive and electrically nonconductive liquid contained in and substantially filling said envelope; an electric heat source comprising a semiconductor electron valve immersed in said liquid; means attached to said envelope for holding said envelope in contiguous heat-transferring relationship with a selected portion of an article; a portable source of electrical energy; and control circuit means for interconnecting said source of energy and said valve, whereby said valve is energized by current from said source and the heat generated thereby is transferred to said liquid and to said selected portion of the article.
Claim 7
Dependent Claim 136 words
A portable therapeutic heating device for localized heating of an article comprising the combination of first and second flexible thermally conductive and electrically nonconductive sheets of substantially liquid impermeable material bonded to each other along their margins to form a sealed envelope; a thermally conductive and electrically nonconductive liquid contained in and substantially filling said envelope; an electric heat source comprising a semiconductor electron valve immersed in said liquid; means attached to said envelope for holding said envelope in contiguous heat-transferring relationship with a selected portion of an article; a portable source of electrical energy; and control circuit means for interconnecting said source of energy and said valve, whereby said valve is energized by current from said source and the heat generated thereby is transferred to said liquid and to said selected portion of the article.

References Cited (Backward Citations)

US2178397A Cited
US3016446A Cited
US3178559A Cited
US3195539A Cited
US3292628A Cited
US3298368A Cited
US3470350A Cited
US3465120A Cited
US3569666A Cited
US3955063A Cited

USPTO Annuity & Maintenance Windows

Annuity Stage Window Opens Payment Deadline Surcharge Period Until Estimated Fee Status
3.5 Years (Year 4) 1983-05-06 1983-11-05 1984-05-06 $2000.00 Window Closed / Lapsed
7.5 Years (Year 8) 1987-05-06 1987-11-05 1988-05-06 $3760.00 Window Closed / Lapsed
11.5 Years (Year 12) 1991-05-06 1991-11-05 1992-05-06 $7700.00 Window Closed / Lapsed

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