Heating blanket

1. An electric heating pad, mattress or mattress overlay for warming a body of a person or a patient, the electric heating pad, mattress or mattress overlay comprising:

a flexible sheet-like heating element comprising a first side and a second side, the heating element comprising an electrical heating element;

a shell covering the heating element and comprising a first flexible sheet including a first flexible sheet first edge, a first flexible sheet second edge, a first flexible sheet third edge, and a first flexible sheet fourth edge and a second flexible sheet including a second flexible sheet first edge, a second flexible sheet second edge, a second flexible sheet third edge, and a second flexible sheet fourth edge;

one or more welds coupling the first flexible sheet to the second flexible sheet about the first flexible sheet first edge, the first flexible sheet second edge, the first flexible sheet third edge, and the first flexible sheet fourth edge of the first flexible sheet and the second flexible sheet first edge, the second flexible sheet second edge, the second flexible sheet third edge, and the second flexible sheet fourth edge of the second flexible sheet to hermetically seal the heating element therebetween 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 flexible 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 first and second flexible sheets of the shell via the one or more welds and without using connectors that pierce the first and second flexible 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 electric heating pad, mattress or mattress overlay is conformable to curves of the body of the person or the patient.

2. The electric heating pad, mattress or mattress overlay of claim 1 , wherein the flexible insulating layer comprises a foam, a non-woven fibrous material, a woven fabric, a plastic film, a non-flammable material, cotton or fiberglass.

3. The electric heating pad, mattress or mattress overlay of claim 2 , wherein the plastic film is an elastomer.

4. The electric heating pad, mattress or mattress overlay of claim 1 , wherein the flexible insulating layer is an adhesive applied over at least a portion of the first side of the heating element.

5. The electric heating pad, mattress or mattress overlay of claim 4 , wherein the adhesive is silicone.

6. The electric heating pad, mattress or mattress overlay of claim 4 , wherein the adhesive is vinyl.

7. The electric heating pad, mattress or mattress overlay of claim 4 , wherein the adhesive is an elastomer.

8. The electric heating pad, mattress or mattress overlay of claim 1 , wherein the flexible insulating layer is porous.

9. The electric heating pad, mattress or mattress overlay of claim 1 , wherein the one or more welds is a thermal bond.

10. An electric heating blanket, pad, mattress or mattress overlay for warming a body of a person or a patient, the electric heating blanket, pad, mattress or mattress overlay comprising:

a flexible sheet-like heating element comprising a first side and a second side, the heating element comprising an electrical heating element;

a shell covering the heating element and comprising a first flexible sheet including four first flexible sheet edges and a second flexible sheet including four second flexible sheet edges;

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

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

wherein the heating element is secured to the shell via the one or more welds and held in position between the first and second flexible sheets of the shell via the one or more welds and without using connectors that pierce the first and second flexible 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 electric heating blanket, pad, mattress or mattress overlay is conformable to curves of the body of the person or the patient.

11. The electric heating blanket, pad, mattress or mattress overlay of claim 10 , wherein the flexible insulating layer provides at least one of thermal insulation and electrical insulation.

12. The electric heating blanket, pad, mattress or mattress overlay of claim 10 , wherein the plastic film is an elastomer.

13. An electric heating blanket, pad, mattress or mattress overlay for warming a body of a person or a patient, the electric heating blanket, pad, mattress or mattress overlay comprising:

a flexible sheet-like heating element comprising a first side and a second side, the heating element comprising an electrical heating element;

a shell covering the heating element and comprising a first flexible sheet including a first flexible sheet first edge, a first flexible sheet second edge, a first flexible sheet third edge, and a first flexible sheet fourth edge and a second flexible sheet including a second flexible sheet first edge, a second flexible sheet second edge, a second flexible sheet third edge, and a second flexible sheet fourth edge;

one or more welds coupling the first flexible sheet to the second flexible sheet about the first flexible sheet first edge, the first flexible sheet second edge, the first flexible sheet third edge, and the first flexible sheet fourth edge of the first flexible sheet and the second flexible sheet first edge, the second flexible sheet second edge, the second flexible sheet third edge, and the second flexible sheet fourth edge of the second flexible sheet to hermetically seal the heating element therebetween and to define a pouch that encloses the heating element; and

a flexible insulating layer comprising an elastomer applied over at least a portion of the first side of the heating element and covered by the shell, wherein the heating element is secured to the shell via the one or more welds and held in position between the first and second flexible sheets of the shell via the one or more welds and without using connectors that pierce the first and second flexible 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 electric heating blanket, pad, mattress or mattress overlay is conformable to curves of the body of the person or the patient.

14. An electric heating pad, mattress or mattress overlay for warming a body of a person or a patient, the electric heating pad, mattress or mattress overlay 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, the heating element comprising an electrical heating element;

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 flexible material to the second sheet of flexible material about the upper edge, the lower edge, the first side edge, and the second side edge 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 configured to be in conductive contact with the body of the person or the patient when the electric heating pad, mattress or mattress overlay is supporting the body of the person or the patient, 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 heating element is electrically powered, and

wherein the electric heating pad, mattress or mattress overlay is conformable to curves of the body of the person or the patient.

15. The electric heating pad, mattress or mattress overlay of claim 14 , 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 temperature 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 configured to not be in conductive contact with the body of the person or the patient when the electric heating pad, mattress or mattress overlay is supporting the body of the person or the patient.

16. The electric heating pad, mattress or mattress overlay of claim 14 , wherein the flexible insulating layer comprises a foam, a non-woven fibrous material, a woven fabric, a plastic film, a non-flammable material, cotton or fiberglass.

17. The electric heating pad, mattress or mattress overlay of claim 16 , wherein the plastic film is an elastomer.

18. The electric heating pad, mattress or mattress overlay of claim 14 , wherein the flexible insulating layer is an adhesive applied over at least a portion of the heating element.

19. The electric heating pad, mattress or mattress overlay of claim 18 , wherein the adhesive is silicone or an elastomer.