Internal heating element for pipes and tubes

• US 6,516,142 B2
• Filed: 02/12/2001
• Issued: 02/04/2003
• Est. Priority Date: 01/08/2001
• Status: Expired due to Fees

• Current Assignee: Watlow Electric Manufacturing Company
• Original Assignee: Watlow Polymer Technologies
• Inventors: Grant, Mike A., Schlesselman, John W., Tweedy, Clifford D.
• Primary Examiner(s): Walberg, Teresa
• Assistant Examiner(s): CAMPBELL, THOR S
• Application Number:
  US09/781,456
• Publication Number:
  US 20020090210A1
• Time in Patent Office: 722 Days
• Field of Search: 392/465, 392/466, 392/451, 392/459, 392/485, 392/487
• US Class Current: 392/451
• CPC Class Codes: F24H 1/102 with resistance
• CPC Class Codes: H05B 3/54 flexible

Abstract

The heater includes a resistance heating element comprising a resistance heating wire having a pair of terminal ends connected to a pair of electrical connectors and encapsulated with a thin electrically insulating polymeric layer. The resistance heating wire is capable of maintaining a fluid initially heated by a primary heat source substantially at the desired use temperature. A first connecting body is configured to couple to the section of piping containing the fluid. The connecting body includes a fluid inlet port, a fluid outlet port, a fluid passageway defined between the fluid inlet and outlet ports, and an electrical connection port. The resistance heating element is disposed at least partially within the fluid passageway and at least a first one of the terminal ends is coupled to a respective one of the pair of electrical connectors through the electrical connection port.

Claims

1. A hot beverage dispensing apparatus, comprising:

a primary fluid heat source, said primary fluid heat source configured to initially heat a fluid to at least a hot beverage temperature;

a section of piping coupled between an output of said primary fluid heat source and an output of said hot beverage dispensing apparatus;

a low wattage heater disposed in said section of piping to compensate for heat loss to said fluid, said low wattage heater including a resistance heating element including a resistance heating material encapsulated within a thin electrically insulating polymeric layer; and

temperature control means for selectively energizing said resistance heating element to maintain said fluid substantially at at least said hot beverage temperature when said fluid is resident within said section of piping.

2. The apparatus of claim 1, wherein said polymeric layer comprises polysulfone, polycarbonate, polyetherimide, polyether sulfone, polypropylene, a fluorocarbon, epoxy, silicone, phenolic, polyetheretherkeytone, polyphenylene sulfide, or a combination thereof.

3. The apparatus of claim 1, wherein said resistance heating element is spirally shaped.

4. The apparatus of claim 3, wherein said resistance heating element forms a plurality of flexible, spiral forms wound along a common axis, said heating element having a Flux or Watt Density which is lower than that for a Tubular Heating Element of substantially similar Active Element Volume (in³), said spirally shaped heating element having the same or greater overall wattage rating (total watts) than said Tubular Heating Element.

5. The apparatus of claim 4, wherein said plurality of spiral forms comprise a circular, square, oval or rectangular shape.

6. The apparatus of claim 3, wherein said resistance heating material comprises a metal ribbon or wire.

7. The apparatus of claim 1, wherein said low wattage heater includes a connecting body connected to said section of piping, said connecting body including a fluid inlet port, a fluid outlet port, an electrical connection port and a fluid passageway defined between said fluid inlet port and said fluid outlet port, said resistance heating element disposed at least partially within said fluid passageway and said section of piping.

8. The apparatus of claim 1, wherein said low wattage heater includes a first and second connecting bodies disposed at a first and second ends of said section of piping, respectively, each of said connecting bodies including a fluid inlet port, a fluid outlet port, an electrical connection port, and a fluid outlet port, at least a portion of said resistance heating element disposed axially through said section of piping.

9. The apparatus of claim 1, wherein said polymeric layer has a thickness of about 0.001-0.020 inches.

10. A hot beverage dispensing apparatus, comprising:

a primary fluid heat source, said primary fluid heat source configured to initially heat a fluid to at least a hot beverage temperature;

a section of piping coupled between an output of said primary fluid heat source and an output of said hot beverage dispensing apparatus;

a low wattage heater disposed in said section of piping to compensate for heat loss to said fluid, said low wattage heater including a flexible, spirally shaped resistance heating element including a resistance heating material encapsulated within a thin electrically insulating polymeric layer; and

temperature control means for selectively energizing said resistance heating element to maintain said fluid substantially at at least said hot beverage temperature when said fluid is resident within said section of piping.

11. The apparatus of claim 10, wherein said polymeric layer comprises polysulfone, polycarbonate, polyetherimide, polyether sulfone, polypropylene, a fluorocarbon, epoxy, silicone, phenolic, polyetheretherkeytone, polyphenylene sulfide, or a combination thereof.

12. The apparatus of claim 10, wherein said resistance heating element forms a plurality of flexible, spiral forms wound along a common axis, said heating element having a Flux or Watt Density which is lower than that for a Tubular Heating Element of substantially similar Active Element Volume (in³), said spirally shaped heating element having the same or greater overall wattage rating (total watts) than said Tubular Heating Element.

13. The apparatus of claim 12, wherein said plurality of spiral forms comprise a circular, square, oval or rectangular shape.

14. The apparatus of claim 10, wherein said resistance heating material comprises a metal ribbon or wire.

15. The apparatus of claim 10, wherein said low wattage heater includes a connecting body connected to said section of piping, said connecting body including a fluid inlet port, a fluid outlet port, an electrical connection port and a fluid passageway defined between said fluid inlet port and said fluid outlet port, said resistance heating element disposed at least partially within said fluid passageway and said section of piping.

16. The apparatus of claim 10, wherein said low wattage heater includes a first and second connecting bodies disposed at a first and second ends of said section of piping, respectively, each of said connecting bodies including a fluid inlet port, a fluid outlet port, an electrical connection port, and a fluid outlet port, at least a portion of said resistance heating element disposed axially through said section of piping.

17. The apparatus of claim 10, wherein said polymeric layer has a thickness of about 0.001-0.020 inches.