1. An induction heat generation roller device, comprising:a roller main body adapted to be rotatably supported;
an induction heat generator provided within the roller main body and having an induction coil for heating the roller main body inductively;
a cooling mechanism configured to introduce a coolant mist at a coolant mist introduction timing into a clearance portion between the roller main body and the induction heat generator for cooling the roller main body;
an AC voltage application part configured to apply an AC voltage to the induction coil, and vaporizes the coolant mist that has condensed; and
a DC voltage application part configured to apply a DC voltage to the induction coil at a DC voltage introduction timing that is in a timed relationship with the coolant mist introduction timing.