Image forming apparatus capable of suppressing damage to a fixing member while maintaining productivity

An image forming apparatus comprising:

• an image forming unit for forming a toner image on a recording medium;
• a fixing device disposed on a downstream side of the image forming unit in a recording medium conveying direction, the fixing device including a fixing member constituted of a heated rotary member heated by a heating device and a pressure member contacting the heated rotary member so as to form a fixing nip, the fixing device heating and pressing the recording medium passing through the fixing nip so that the toner image is fixed to the recording medium;
• a temperature detection device for detecting surface temperature of the heated rotary member in a non-passing area the recording medium does not pass;
• a driving device for driving recording medium conveying members including the fixing member;
• a printed sheet number counting unit for accumulating and counting the number of printed sheets;
• a fixing voltage power supply for applying a voltage to the heating device;
• and
• a control unit arranged to control the driving device and the fixing voltage power supply, wherein
• the control unit is capable of performing a productivity change mode for changing productivity as the number of printed sheets per unit time, in two or more steps from a default setting, in accordance with a size of the recording medium, and
• when performing the productivity change mode, the control unit changes the productivity in two or more steps from the default setting, on the basis of the accumulated number of printed sheets from start of the productivity change mode counted by the printed sheet number counting unit, and the surface temperature of the non-passing area detected by the temperature detection device, and changes control temperature of the fixing member in accordance with the productivity.