Image forming apparatus with recording material loop forming and control means

An image forming apparatus comprising:

• image forming means for forming an unfixed toner image on recording material;
• fixing means having a pair of rotatable members for conveying the recording material therebetween and fixing said unfixed toner image on the recording material, a distance along a conveyance path of the recording material between a position at which the unfixed toner image is formed on the recording material by said image forming means and a nip position of said pair of rotatable members being shorter than the length of the recording material used with respect to a direction of conveyance of the recording material;
• conveying means for conveying the recording material having said unfixed toner image formed thereon to said fixing means;
• drive means for rotatably driving said pair of rotatable members selectively at a first peripheral speed lower than a speed at which said conveying means conveys the recording material and a second peripheral speed higher than the speed at which said conveying means conveys the recording material;
• and
• control means for controlling said drive means, said control means controlling said drive means so as to rotate said pair of rotatable members at said first peripheral speed to thereby convey the recording material and to form a loop of the recording material having said unfixed toner image formed thereon between the nip position of said pair of rotatable members and the position at which the unfixed toner image is formed on the recording material by said image forming means, and thereafter to change said first peripheral speed to said second peripheral speed, thereby suppressing growth of the loop of said recording material greater than a predetermined amount.