Variable pitch resistance coil heater
A heater is provided that includes a resistance coil assembly defining a first end portion having a first conducting pin and a second end portion having a second conducting pin, and a resistance coil disposed between the first end portion and the second end portion, the resistance coil defining a plurality of different pitches between the first end portion and the second end portion. An insulating material surrounds the resistance coil assembly, and a sheath surrounds the insulating material. The plurality of different pitches provide a variable watt density such that a predetermined temperature profile is provided along the sheath.
1. A heater comprising:
a resistance coil assembly defining a first end portion having a first conducting pin and a second end portion having a second conducting pin, and a resistance coil disposed between the first end portion and the second end portion, the resistance coil having a continuously variable pitch along the length of the resistive coil between the first and second end portions;
an insulating material surrounding the resistance coil assembly; and
a sheath surrounding the insulating material,
wherein the continuously variable pitch provides a variable watt density such that a predetermined temperature profile is provided along the sheath.
2. The heater according to claim 1 , wherein the predetermined temperature profile is constant along the sheath.
3. The heater according to claim 1 , wherein the insulating material is a compacted Magnesium Oxide (MgO).
4. The heater according to claim 3 , wherein the insulating material further comprises Boron Nitride (BN).
5. The heater according to claim 1 , wherein the resistance coil defines a helical shape.
6. The heater according to claim 1 , wherein the resistance coil is a constant diameter.
7. The heater according to claim 1 , wherein the resistance coil defines a conical shape.
8. The heater according to claim 1 , wherein the resistance coil is a nichrome material.
9. The heater according to claim 1 , wherein the pitches of the continuously variable pitch are in the range of approximately 1.5 inches to approximately 4.5 inches.
10. An electric heat exchanger comprising:
a heater comprising:
a resistance coil assembly defining a first end portion having a first conducting pin and a second end portion having a second conducting pin, and a resistance coil disposed between the first end portion and the second end portion, the resistance coil having a continuously variable pitch along the length of the resistive coil between the first and second end portions;
an insulating material surrounding the resistance coil assembly; and
a sheath surrounding the insulating material,
wherein the continuously variable pitch provides a variable watt density such that a predetermined temperature profile is provided along the sheath.
11. The heater according to claim 10 , wherein the predetermined temperature profile is constant along the sheath.
12. A resistance element for use in a heater comprising:
a resistance body defining a coil shape having a first end portion and a second end portion, and the coil shape having a continuously variable pitch along the length of the resistive coil between the first and second end portions,
wherein the continuously variable pitch provides a variable watt density such that a predetermined temperature profile is provided to a heating target.
13. The resistance element according to claim 12 , wherein the predetermined temperature profile is constant along the heating target.