An induction heat fixing device has coil portions with electric wires wound around the outer surface of a cylindrical main bobbin, grooves and flanges formed at both ends of the main bobbin. The electrode assembly is contained in a bottomed cylindrical container such that the negative electrode forms the outermost peripheral portion. A mechanism winds and unwinds the torsion spring to respectively grip or release said shank, the winding being in a rotational direction consistent with a normal operating rotational direction of said chuck such that said shank tends to further wind the torsion spring for further self-tightening in normal operation. The cache, comprising a plurality of sets, is employable to disable the replacement of at least one of the plurality of sets as a function of the tag replacement control indicia. The period of off time of the communication module in the intermittent operation mode thereof is shorter than a period of transmission time of the remote controller for transmitting a power-on signal that causes the electronic apparatus main body to shift the standby state thereof to a normal state thereof. The measured deflections are correlated to actual pressures within the chambers.