Method for manufacturing a heat generating apparatus

• US 6,453,648 B1
• Filed: 07/06/1999
• Issued: 09/24/2002
• Est. Priority Date: 07/06/1999
• Status: Expired due to Term

• Current Assignee: Nuvo Pharmaceuticals Inc. (Searchlight Pharma, Inc.), University of Utah Research Foundation (State of Utah)
• Original Assignee: Zars, Inc.
• Inventors: Zhang, Hao, Zhang, Jie, Rigby, Larry, Hull, Wade A.
• Primary Examiner(s): Rada, Rinaldi I.
• Assistant Examiner(s): HARMON, CHRISTOPHER R
• Application Number:
  US09/347,963
• Publication Number:
  US 20020083685A1
• Time in Patent Office: 1,176 Days
• Field of Search: 252/182.29, 252/183.12, 252/962, 607/76, 607/114, 534/69, 534/74, 534/77
• US Class Current: 53/469
• CPC Class Codes: A61F 2007/0226 adhesive, self-sticking
• CPC Class Codes: A61F 2007/0249 with a layer having low heat transfer capability
• CPC Class Codes: A61F 7/034 Flameless

Abstract

The present invention relates to a method for manufacturing a heating device which is capable of generating heat when exposed to oxygen. The heat generating element comprises activated carbon and iron is used to generate an exothermic oxidation reaction within the heating device. Introducing an oxidation inhibitor during the manufacturing process allows the manufacturing of the device to take place in ambient atmospheric conditions. The present invention also includes a loading facilitator which allows the heat generating medium to be more easily and efficiently loaded into the heat generating device. When appropriate, the oxidation inhibitor and loading facilitator can be removed.

Claims

1. A method for manufacturing a heating device capable of generating heat when exposed to oxygen, comprising the steps of:

providing a sheet of material as the bottom wall of a chamber;

providing a heat generating medium in a bag permeable to air and to an oxidation facilitating liquid, said heat generating medium being capable of generating heat when combined with the oxidation facilitating liquid comprising water and subsequently exposed to oxygen;

placing said bag of heat generating medium without an oxidation facilitating liquid onto said bottom wall;

disposing a predetermined amount of said oxidation facilitating liquid comprising water into said bag containing said heat generating medium;

placing a sheet of material on said bag containing said heat generating medium and said bottom wall to form a cover, said cover having selected air permeability; and

securing said cover onto said bottom wall to enclose said heat generating medium.

2. The method as claimed in claim 1, wherein said heat generating medium comprises iron powder, activated carbon, and a compound selected from the group of sodium chloride, potassium chloride, and magnesium chloride.

3. The method as claimed in claim 1, wherein said heat generating medium comprises wood powder.

4. The method as claimed in claim 1, wherein said bottom wall is a plastic tape.

5. The method as claimed in claim 1, wherein said securing of said cover onto said bottom wall comprises adhering said cover along an edge onto said bottom wall.

6. The method as claimed in claim 1, wherein said securing of said cover onto said bottom wall comprises heat sealing said cover along an edge onto said bottom wall.

7. The method as claimed in claim 1, wherein said cover with selected air permeability comprises a sheet of material substantially impermeable to air;

said sheet defining a selected number of holes with selected size.

8. The method as claimed in claim 7, wherein said selected number of holes are covered with a membrane with selected air permeability.

9. The method as claimed in claim 7, wherein said cover comprises a sheet of material having thermal insulation properties.

10. The method as claimed in claim 1, wherein said heating device further comprises means for affixing itself onto human skin.

11. The method as claimed in claim 10, wherein said means for affixing comprises an adhesive area on said chamber.

12. A method for manufacturing a heating device capable of generating heat when exposed to oxygen, comprising the steps of:

providing a sheet of material as the bottom wall of a chamber;

providing a heat generating medium in a bag permeable to air and to an oxidation facilitating liquid, said heat generating medium being capable of generating heat when combined with the oxidation facilitating liquid comprising water and subsequently exposed to oxygen;

placing said bag of heat generating medium without an oxidation facilitating liquid onto said bottom wall; and

disposing a predetermined amount of said oxidation facilitating liquid comprising water onto said bag containing said heat generating medium whereby said oxidation facilitating liquid is absorbed through said bag and into said heat generating medium;

placing a sheet of material on said bag containing said heat generating medium and said bottom wall to form a cover, said cover having selected air permeability; and

securing said cover onto said bottom wall to enclose said heat generating medium.

13. The method as claimed in claim 12, wherein said heat generating medium comprises iron powder, activated carbon, and a compound selected from the group of sodium chloride, potassium chloride, and magnesium chloride.

14. The method as claimed in claim 12, wherein said heat generating medium comprises wood powder.

15. The method as claimed in claim 12, wherein said cover with selected air permeability comprises a sheet of material substantially impermeable to air;

said sheet defining a selected number of holes with selected size.

16. The method as claimed in claim 15, wherein said selected number of holes are covered with a membrane with selected air permeability.

17. The method as claimed in claim 12, wherein said heating device further comprises means for affixing itself onto human skin.