Jet apparatus having an ink jet head and temperature controller for that head

An ink jet apparatus, comprising:

• an ink jet head having a heat generating resistance element, said ink jet head discharging ink droplets by causing a change in a state of an ink by utilizing heat generated by said heat generating resistance element;
• conveying means for conveying a recording medium to be recorded upon in a conveyance direction, so that a predetermined recording image is formed on said recording medium by ink droplets discharged by said ink jet head;
• heat exchanging means for exchanging heat with said head, said heat exchanging means being attached to a side surface of said head where said element is provided;
• heating means for heating said exchanging means, said heating means being a part of said heat exchanging means;
• cooling means for cooling said heat exchanging means;
• temperature detecting means for detecting a temperature of said heat exchanging means;
• and
• control means for controlling driving of said heating means and said cooling means based on the temperature detected by said temperature detecting means;
• wherein said head to which said heat exchanging means is attached is joined to said apparatus so that said heat exchanging means is positioned at a downstream side in said conveyance direction of said recording medium.