Image forming apparatus with simplex and duplex operations and cleaning mode

An image forming apparatus comprising:

• a toner image forming portion configured to form a toner image on a recording paper;
• a fixing portion including a first rotatable member and a second rotatable member to fix the toner image on the recording paper while nipping and feeding the recording paper carrying the toner image formed by said toner image forming portion;
• a feeding portion configured and positioned to reverse a facing orientation of the recording paper on which the toner image is fixed by said fixing portion and refeed the recording paper to said toner image forming portion and said fixing portion;
• a first integrating portion configured to integrate a number of the executions of the operations of a simplex mode in which the toner image is formed only on one side of the recording paper;
• an executing portion configured to execute, when the integrated value of said first integrating portion is not less than a predetermined value, an operation in a cleaning mode in which a predetermined toner image is formed and fixed on the one side of the recording paper by said toner image forming portion and said fixing portion, and thereafter, the recording paper being refed by said feeding portion to said toner image forming portion and then to said fixing portion with the reversed facing orientation, so that the second rotatable member is cleaned;
• a second integrating portion configured to integrate a number of executions of operations of a duplex mode in which toner images are formed on both sides of the recording paper;
• and
• a resetting portion configured to reset the integrated value of said first integrating portion when the integrated value of said second integrating portion reaches a predetermined value.

An image forming apparatus comprising:

• a toner image forming portion configured to form a toner image on a recording paper;
• a fixing portion including a first rotatable member and a second rotatable member to fix the toner image on the recording paper while nipping and feeding the recording paper carrying the toner image formed by the toner image forming portion;
• a feeding portion configured and positioned to reverse a facing orientation of the recording paper on which the toner image is fixed by the fixing portion and refeed the recording paper to the toner image forming portion and the fixing portion;
• an executing portion configured to execute an operation in a cleaning mode in which a predetermined toner image is formed and fixed on one side of the recording paper by the toner image forming portion and the fixing portion, and thereafter, the recording paper being refed by the feeding portion to the toner image forming portion and then to the fixing portion with the reversed facing orientation, so that the second rotatable member is cleaned;
• a counting portion configured to count a number of the executions of the operations of a simplex mode in which the toner image is formed only on the one side of the recording paper;
• a notifying portion configured to notify for promoting execution of the cleaning mode when the counted value of the counting portion is not less than a predetermined value;
• and
• a correcting portion configured to correct the counted value of the counting portion in accordance with an execution of a duplex mode in which toner images are formed on both sides of the recording paper.

An image forming apparatus comprising:

• a toner image forming portion configured to form a toner image on a recording paper;
• a fixing portion including a first rotatable member and a second rotatable member to fix the toner image on the recording paper while nipping and feeding the recording paper carrying the toner image formed by the toner image forming portion;
• a feeding portion configured and positioned to reverse a facing orientation of the recording paper on which the toner image is fixed by the fixing portion and refeed the recording paper to the toner image forming portion and the fixing portion;
• a counting portion configured to count a number of the executions of the operations of a simplex mode in which the toner image is formed only on one side of the recording paper;
• an executing portion configured to execute, when the counted value of the counting portion is not less than a predetermined value, an operation in a cleaning mode in which a predetermined toner image is formed and fixed on the one side of the recording paper by the toner image forming portion and the fixing portion, and thereafter, the recording paper being refed by the feeding portion to the toner image forming portion and then to the fixing portion with the reversed facing orientation, so that the second rotatable member is cleaned;
• and
• a resetting portion configured to reset the counted value of the counting portion in accordance with an execution of a duplex mode in which toner images are formed on both sides of the recording paper.