Electrical resistance heater assembly and method of use
An electrical resistance heating assembly comprises a heater ribbon woven through a first mica board. The heater ribbon extends upwardly from a top surface of the first mica board to provide heat to a fluid passing over the upwardly extending heater ribbon. The heat ribbon on an underside of the first mica board is electrically isolated by a second mica board positioned adjacent the first mica board. The first and second mica boards are held together with by a clamp-containing metal place positioned adjacent the second mica board with the clamps bent over the first mica board to keep the mica boards together.
1. An electric resistance heater assembly comprising:
a) a first insulator having a plurality of spaced apart openings therein and having an annular shape;
b) at least one heater element woven through the plurality of openings so that first portions of the heater element extends upwardly from a top surface of the first insulator and second portions of the heater element run along a bottom surface of the first insulator;
c) a second insulator being generally annular in shape, a top surface thereof positioned adjacent to the bottom surface of the first insulator to electrically isolate the second portions of the heater element;
d) a plate positioned adjacent a bottom surface of the second insulator, the plate having an annular shape with inner and outer peripheral edges, the plate further including a plurality of tabs, each of the tabs located on either an inner or an outer peripheral edge of the plate and extending therefrom, the tabs sized to be bent over the first and second insulators to clamp the first and second insulators together to form an annular electric resistance heater assembly comprising the first and second insulators and the plate; and
e) means for mounting the annular electrical resistance heater assembly to a structure to support the heater assembly in place.
2. The heater assembly of claim 1 , wherein each of the first and second insulators are mica boards.
3. The heater assembly of claim 1 , wherein each of the first and second insulators have notches in an outer and inner edge thereof, each notch aligned with each tab of the plate.
4. The heater assembly of claim 1 , wherein the means for mounting the plate further comprises a plurality of members, each member extending upwardly from the outer peripheral edge of the plate.
5. The heater assembly of claim 4 , wherein each of the first and second insulators have a notch to receive each member.
6. The heater assembly of claim 1 , wherein a second heater element is annularly arranged adjacent to said one heater element.
7. The heater assembly of claim 1 , wherein the plurality of tabs are arranged in pairs that oppose each other from the inner and outer peripheral edges of the plate.
8. The heater assembly of claim 1 , wherein the first and second insulators are made in segments, the segments of each of the first and second insulators forming joints with at least some of the tabs of the plurality of tabs positioned at the joints.
9. The heater assembly of claim 8 , wherein the joints of each of the segments of the first and second insulators are 90 degrees apart.
10. The heater assembly of claim 1 , wherein the plate includes a terminal support structure extending from an edge thereof.
11. The heater assembly of claim 1 , wherein said at least one heater element is a heater ribbon.
12. The heater assembly of claim 4 wherein said each member extends upwardly in the direction of said first and second insulators.