Sheet winding detecting device and image forming apparatus

An image forming apparatus that forms an image on a recording sheet, comprising:

• conveying means for conveying the recording sheet while rotating, said conveying means having a sheet passing area;
• voltage applying means for applying voltage to said conveying means;
• a conductive member disposed in the sheet passing area of said conveying means;
• voltage detecting means for detecting voltage related to said conveying means via said conductive member;
• holding means for holding said conductive member in contact or non-contact with the sheet passing area of said conveying means;
• recording sheet winding detecting means for detecting whether the recording sheet is wound around said conveying means according to the voltage applied by said voltage applying means and the voltage detected by said voltage detecting means when said conductive member is held in contact with the sheet passing area of said conveying means;
• and
• function status detecting means for detecting whether said recording sheet winding detecting means is malfunctioning.

An image forming apparatus that forms an image on a recording sheet, comprising:

• fixing means for fixing a toner image formed on the recording sheet bearing the toner image while conveying the recording sheet, said fixing means having a rotatable member having a sheet passing area and disposed in contact with a reverse side of the recording sheet bearing the toner image;
• voltage applying means for applying voltage reverse in polarity to toner to the rotatable member;
• voltage detecting means for detecting voltage related to the rotatable member in the sheet passing area of the rotatable member;
• and
• recording sheet winding detecting means for detecting whether the recording sheet is wound around the rotatable member according to the voltage detected by said voltage detecting means.