Cleaning system and image forming method

A cleaning apparatus comprising:

• a cleaning roller being either conductive or semi-conductive and in contact with an image bearing member carrying a charged toner;
• a constant current source to apply a bias voltage, having a polarity opposite to that of toner utilized for a developing operation performed on said image bearing member, onto said cleaning roller;
• a cleaning blade contacting said image bearing member and located at a downstream side of said cleaning roller in a moving direction of said image bearing member;
• and
• a control section to control said constant current source so as to increase an absolute value of a toner-collecting voltage according to an increase of an image-forming amount, and so as to apply either said toner-collecting voltage or a toner-releasing voltage onto said cleaning roller by selecting one of them in a time-sharing manner,
• wherein both said toner-collecting voltage and said toner-releasing voltage are equivalent to said bias voltage.

An image-forming apparatus, comprising:

• an image bearing member;
• a developing device;
• and
• a cleaning apparatus,
• wherein said cleaning apparatus comprises:
• a cleaning roller being either conductive or semi-conductive and in contact with said image bearing member carrying charged toner;
• a constant current source to apply a bias voltage, having a polarity opposite to that of toner utilized for a developing operation performed on said image bearing member, onto said cleaning roller;
• a cleaning blade contacting said image bearing member and located at a downstream side of said cleaning roller in a moving direction of said image bearing member;
• and
• a control section to control said constant current source so as to increase an absolute value of a toner-collecting voltage according to an increase of an image-forming amount, wherein said toner-collecting voltage is equivalent to said bias voltage.

An image forming apparatus, comprising:

• a first image bearing member;
• a plurality of developing devices arranged around a periphery of said first image bearing member;
• a second image bearing member on which a toner image formed on said first image bearing member is temporarily transferred;
• a cleaning apparatus equipped for either said first image bearing member or said second image bearing member;
• wherein said cleaning apparatus comprises:
• a cleaning roller being either conductive or semi-conductive and in contact with said first image bearing member or said second image bearing member carrying charged toner;
• a constant current source to apply a bias voltage, having a polarity opposite to that of toner utilized for a developing operation performed on said first image bearing member or said second image bearing member, onto said cleaning roller;
• a cleaning blade contacting said first image bearing member or said second image bearing member and located at a downstream side of said cleaning roller in a moving direction of said first image bearing member or said second image bearing member;
• and
• a control section to control said constant current source so as to increase an absolute value of a toner-collecting voltage according to an increase of an image-forming amount, wherein said toner-collecting voltage is equivalent to said bias voltage.