Image forming apparatus having cooling efficiency switching control function

An image forming apparatus comprising:

• means for forming an image based on image data, said image forming means at least having a thermal source for substantially generating heat;
• means for forcibly releasing out of said apparatus heat which is generated by the thermal source and which accumulates as a result of said image forming means forming an image;
• means for counting a time during which said releasing means is driven after formation of an image;
• means for switching a heat releasing rate of said heat releasing means between at least two level modes, in accordance with a time counted by said time counting means;
• and
• means for driving said heat releasing means in a mode having a higher cooling efficiency than any other of said level modes, during a time counted by said counting means, and controlling the temperature within said apparatus.

An image forming apparatus comprising:

• means for forming an image based on image data, said image forming means having at least a thermal source for generating heat;
• means for forcibly expelling from said apparatus heat which is generated by the thermal source when said image forming means forms an image;
• means for detecting the temperature within said apparatus;
• means for detecting the temperature within said apparatus;
• means for switching the heat releasing rate of said heat releasing means between at least two level modes, in accordance with the temperature detected by said temperature detecting means including at times after copying operation is completed;
• and
• means for driving said heat releasing means in a mode having a higher cooling efficiency than any other of at least two level modes, to control the temperature within said apparatus when, as a result of successive image formation, the number of times image formation is performed exceeds a predetermined value.