Patent ID: 9213300
Filing Date: 2015-12-15
Classification: G03G

Abstract:
1. An image forming apparatus comprising: a photoreceptor drum having a protective layer formed on its surface; a charging bias supply circuit configured to generate a first charging bias voltage at the time of printing; a charging unit configured to, upon application of the first charging bias voltage, cause a proximity discharge, including a positive discharge and a negative discharge, between the surface of the photoreceptor drum and the charging unit, thereby charging the surface; a scanning optical system configured to irradiate the surface of the photoreceptor drum with an optical beam, thereby forming an electrostatic latent image, at the time of printing; a developing unit configured to develop the electrostatic latent image formed on the photoreceptor drum, at the time of printing; a control circuit configured to determine whether to execute a recovery mode based on temperature, humidity, or a combination thereof; and a cleaning unit configured to rub the surface of the photoreceptor drum charged by the charging unit, at the time of printing, wherein, the charging bias supply circuit is configured to generate a second charging bias voltage that causes no positive discharge between the charging unit and the photoreceptor drum, during the recovery mode, the charging unit is configured to charge the surface of the photoreceptor drum upon application of the second charging bias voltage during the recovery mode, and the cleaning unit is configured to rub the surface of the photoreceptor drum charged by the second charging bias voltage, during the recovery mode.