Patent ID: 7800026

Claim:
A heating body comprising: a lead rod that conducts electricity from an external power source; a supporting member connected to the lead rod, the supporting member having a predetermined supporting force; a plurality of heaters, each coiled around the supporting member, having different thermal expansion coefficients, respectively, the plurality of heaters including first and second heating members, the first heating member disposed at an outside of the second heating member, the second heating member disposed around the supporting member such that the second heating member is disposed closer to the supporting member than the first heating member, the first heating member having a relatively higher thermal expansion coefficient than the second heating member; and a tube in which the heaters are disposed, wherein at least one of the plurality of heaters supports at least one other heater, wherein the tube is formed in a hollow shape, and the heaters are spaced apart from an innermost internal side of the tube to form an empty space between an external side of the plurality of heaters and the innermost internal side of the tube.