Resistive heater with temperature sensing power pins

Patent metadata

Field	Value
Publication number	US-11576233-B2
Application number	US-202016923597-A
Country	US
Kind code	B2
Filing date	Jul 8, 2020
Priority date	May 29, 2015
Publication date	Feb 7, 2023
Grant date	Feb 7, 2023

Abstract

A heater includes a first power pin and a second power pin made of dissimilar materials, and a resistive heating element made of a material different from those of the first and second power pins. The resistive heating element includes a first end electrically and directly connected to the first power pin to form a first thermocouple junction and a second end and electrically and directly connected to the second power pin to form a second thermocouple junction. The first and second power pins perform a dual function of supplying power to the resistive heating element and detecting changes in voltage at the first and second thermocouple junctions without interrupting the power supplied to the resistive heating element.

First claim

What is claimed is:

1. A heater comprising:
a first power pin made of a first conductive material;
a second power pin made of a second conductive material that is dissimilar from the first conductive material of the first power pin; and
a resistive heating element having a first end and a second end and being made of a material that is different from the first and second conductive materials of the first and second power pins,
wherein the first end of the resistive heating element is electrically and directly connected to the first power pin to form a first thermocouple junction, and the second end of the resistive heating element is electrically and directly connected to the second power pin to form a second thermocouple junction, the resistive heating element having a predetermined shape with the first and second ends, and
a controller connected electrically with the first and second power pins, and configured to perform a dual function of supplying a power to the resistive heating element to generate heat and receiving signals relating to changes in voltage at the first and second thermocouple junctions to determine an average temperature of the resistive heating element.

2. The heater according to claim 1 , wherein the first power pin and the second power pin are different nickel alloys.

3. The heater according to claim 1 , wherein the resistive heating element is a nichrome alloy material.

4. The heater according to claim 1 , wherein the controller is configured to switch between a heating mode for directing the power to the resistive heating element and a measuring mode for measuring the changes in voltage at the first and second thermocouple junctions to determine the average temperature of the heater.

5. The heater according to claim 1 , wherein the controller is configured to measure the changes in voltage at the first and second thermocouple junctions and allow the power to be supplied to the resistive heating elements at different times.

6. The heater according to claim 1 , wherein the heater is a cartridge heater comprising:
a non-conductive portion defining a proximal end and a distal end, the non-conductive portion having first and second apertures extending through at least the proximal end, wherein the first and second power pins are disposed within the first and second apertures, and the resistive heating element is disposed around the non-conductive portion;
a sheath surrounding the non-conductive portion; and
a sealing member disposed at the proximal end of the non-conductive portion and extending at least partially into the sheath.

7. The heater according to claim 1 , further comprising:
insulation disposed over the resistive heating element and at least a portion of the first and second power pins; and
a protective member disposed over the insulation.

8. The heater according to claim 7 , wherein the heater is a layered heater, the insulation is a dielectric layer, and the protective member is a protective layer.

9. A heat exchanger comprising the heater according to claim 1 .

10. The heater according to claim 1 , wherein the heater is selected from the group consisting of a cartridge heater, a tubular heater, a layered heater, a polymer heater, a flexible heater, heat trace, and a ceramic heater.

11. The heater according to claim 1 , further comprising a pair of lead wires connected to the first power pin and the second power pin.

12. The heater according to claim 11 , wherein the pair of lead wires are made of a same conductive material.

13. A heater system comprising:
a heater comprising:
a first power pin made of a first conductive material;
a second power pin made of a second conductive material that is dissimilar from the first conductive material; and
a resistive heating element having a first end and a second end and being made of a material that is different from the first and second conductive material of the first and second power pins,

wherein the first end of the resistive heating element is electrically and directly connected to the first power pin to form a first thermocouple junction, and the second end of the resistive heating element is electrically and directly connected to the second power pin to form a second thermocouple junction, the resistive heating element having a predetermined shape with the first and second ends; and
a controller in electrically communication with the first and second power pins and configured to determine an average temperature of the heater based on signals relating to changes in voltage at the first and second thermocouple junctions through the first and second power pins and allow a power to be supplied to the resistive heating element through the first and second power pins to generate a heat output.

14. The heater system according to claim 13 , further comprising a switching device for switching the controller between a heating mode and a measuring mode.

15. The heater system according to claim 14 , wherein the controller receives the signals from the first and second thermocouple junctions through the first and second power pins during the measuring mode.

Assignees

• Watlow Electric Mfg

Inventors

• Reynolds Jack
• Steinhauser Louis P
• Spooler Jake
• Bohlinger William

Classifications

• H05B3/06 Primary

  Heater elements structurally combined with coupling elements or holders · CPC title

• H05B1/0261

  of food · CPC title

• H05B1/0202 Primary

  Switches · CPC title

• H05B3/18

  the conductor being embedded in an insulating material · CPC title

• H05B3/48

  heating conductor embedded in insulating material · CPC title