Heating blanket

1. An electric blanket for warming a body of a person or a patient, the blanket comprising:

a flexible sheet-like heating element comprising a first side and a second side;

a shell covering the heating element and comprising a first flexible sheet having an edge and a second flexible sheet having an edge;

one or more welds coupling the first flexible sheet to the second flexible sheet about the edges of the sheets to hermetically seal the heating element there between and to define a pouch that encloses the heating element; and

a flexible insulating layer extending over the first side of the heating element and covered by the shell,

wherein the insulating layer provides at least one of thermal insulation and electrical insulation,

wherein the heating element is secured to the shell via the one or more welds and held in position between the two sheets of the shell via one or more welds and without using connectors that pierce the two sheets of the shell and without using an adhesive bond that adheres the first or second side of the heating element to the shell, and

wherein the blanket is conformable to curves of the body of the person or the patient.

2. The electric heating blanket of claim 1 , wherein the heating blanket is a pad.

3. The electric heating blanket of claim 2 , wherein the pad is a mattress or mattress overlay.

4. The electric heating blanket of claim 1 , wherein the insulating layer comprises one of a foam, a high loft non-woven fibrous material, a low loft non-woven fibrous material, a woven fabric, such as cotton or fiberglass, a thin plastic film, cotton, a non-flammable material, cotton and fiberglass.

5. The electric heating blanket of claim 4 , wherein the thin plastic film is an elastomer.

6. The electric heating blanket of claim 1 , wherein the insulating layer is an adhesive applied over at least a portion of the side of the heating element.

7. The electric heating blanket of claim 6 , wherein the adhesive is silicone.

8. The electric heating blanket of claim 6 , wherein the adhesive is vinyl.

9. The electric heating blanket of claim 6 , wherein the adhesive is an elastomer.

10. The electric heating blanket of claim 1 , wherein the weld is a thermal bond.

11. The electric heating blanket of claim 1 , wherein the weld is an adhesive bond.

12. An electric heating blanket for warming a body of a person or a patient, the blanket comprising:

a flexible sheet-like heating element comprising a first side, a second side, an upper edge, a lower edge, a first side edge, and a second side edge;

a shell covering the heating element, the shell comprising a first sheet of flexible material and a second sheet of flexible material;

a weld coupling the first sheet of the shell to the second sheet of the shell about the edges of the heating element to define a pouch that encloses the heating element without using an adhesive bond that adheres the first or second side of the heating element to the shell, wherein the weld is one of a RF weld, an ultrasonic weld, or a heat bond, the heating element being secured to the shell and held in position via the weld;

a flexible insulating layer extending over the first side of the heating element and covered by the shell;

a temperature sensor coupled to the heating element at a first location, wherein the heating element is in conductive contact with a body when the blanket is draped over the body, and wherein the first location defines a first temperature zone of the heating element;

wherein the heating element has a surface area of generally uniform electrical resistance per unit area such that the heating element produces a substantially uniform watt density output across the surface area when the element is electrically powered; and

wherein the blanket is conformable to curves of the body of the person or the patient.

13. The electric heating blanket of claim 12 , further comprising:

a temperature controller coupled to the temperature sensor; and

an electric power source coupled to the heating element and to the temperature controller, the power source being controlled by the controller, according to a sensed temperature of the first temperature zone, as sensed by the temperature sensor, in order to maintain a first temperature of the first temperature zone lower than a second temperature of a second temperature zone of the surface area of the heating element, the second temperature zone being defined by a second location of the heating element that is not in conductive contact with the body when the blanket is draped over the body.

14. The electric heating blanket of claim 12 , wherein the heating blanket is a pad.

15. The electric heating blanket of claim 14 , wherein the pad is a mattress or mattress overlay.

16. The electric heating blanket of claim 12 , wherein the insulating layer comprises a foam, a high loft non-woven fibrous material, a low loft non-woven fibrous material, a woven fabric, such as cotton or fiberglass, a thin plastic film, cotton, a non-flammable material, cotton or fiberglass.

17. The electric heating blanket of claim 16 , wherein the thin plastic film is an elastomer.

18. The electric heating blanket of claim 12 , wherein the insulating layer is an adhesive applied over at least a portion of the heating element.

19. The electric heating blanket of claim 18 , wherein the adhesive is silicone.

20. The electric heating blanket of claim 18 , wherein the adhesive is an elastomer.

21. The electric heating blanket of claim 1 , wherein the weld is one of a RF weld, an ultrasonic weld, or a heat bond.