Patent ID: 6952539

Claim:
An image forming apparatus having: image forming means for forming an image on an image bearing member; transferring means for electrostatically transferring the image on said image bearing member to a transferring medium; said transferring means being provided with a transferring member capable of contacting with said image bearing member, and voltage applying means for applying a voltage to said transferring member; electric current detecting means for detecting an electric current flowing from said voltage applying means to said transferring member; and control means for performing an electric current detecting operation of detecting the electric current flowing when said voltage applying means applies a predetermined voltage before an image transferring operation of said transferring means by said electric current detecting means, and determining a transfer voltage applied to said transferring member during the image transferring operation, on the basis of a result of the detection by said electric current detecting operation; wherein said electric current detecting operation is performed a plurality of times, and a time required for an electric current detecting operation performed before a certain electric current detecting operation performed at and after the second time is shorter than a time required for said certain electric current detecting operation.