Bias applying method for an image forming apparatus

摘要

In an electrophotographic image forming apparatus of the type including a plurality of image carriers (40) arranged along an image transfer belt (10) and an image transferring device (62) configured to transfer toner images of different colors from the image carriers (40) to a sheet being conveyed by an image transfer belt or by way of the image transfer belt (10) by applying a bias to the belt (10), a bias applying method of the present invention can measure a current leaking between a plurality of high-tension power supply sections (300,310,320,330) or to the ends thereof as AC resistances between respective terminals and therefore to accurately measure the leak currents of DC components. Therefore, when relatively high DC components are selected, a difference in current between a plurality of power supply sections can be maintained constant.