Image forming apparatus and cleaning method for contact-charging member

An image forming apparatus comprising:

• a rotatable image bearing member;
• a contact-charging member which contacts a surface of said image bearing member, said contact-charging member to charge said image bearing member by applying a predetermined voltage to said contact-charging member,
• wherein a charging potential of said contact-charging member is changed to a cleaning potential for transferring a residual toner that is stuck on a surface of said contact-charging member facing said image bearing member onto said image bearing member while said image bearing member stops rotating, and wherein the cleaning potential is formed by applying an AC voltage to said contact-charging member.

An image forming apparatus having a contact-charging system in which a contact-charging member contacts a surface of a rotatable image bearing member, said image bearing member is charged with said contact-charging member to which a predetermined charging voltage is applied, and said image bearing member can rotate in a reverse direction to a rotation direction in image forming operation, wherein said image forming apparatus comprises:

• a voltage selecting device that switches a voltage applied to said contact-charging member to be different from a voltage in a time period of the image forming operation while said image bearing member is rotated in a reverse direction to the rotation direction in the image forming operation, wherein said contact-charging member is also used as a cleaning member that cleans a surface of said image bearing member.

An image forming apparatus having a contact-charging system in which a contact-charging member contacts a surface of a rotatable image bearing member, said image bearing member is charged with said contact-charging member to which a predetermined charging voltage is applied, and said image bearing member can rotate in a reverse direction to a rotation direction in image forming operation, wherein said image forming apparatus comprises:

• a voltage selecting device that switches a voltage applied to said contact-charging member to be different from a voltage in a time period of the image forming operation while said image bearing member is rotated in a reverse direction to the rotation direction in the image forming operation, wherein said contact-charging member has a configuration of a blade.

An image forming apparatus having the contact-charging system in which a contact-charging member contacts a surface of a rotatable image bearing member, said image bearing member is charged with said contact-charging member to which a predetermined charging voltage is applied, and said image bearing member can rotate in a reverse direction to a rotation direction in image forming operation, wherein said image forming apparatus comprises:

• a voltage selecting device that switches a voltage applied to said contact-charging member to be different from a voltage in a time period of the image forming operation while said image bearing member is rotated in a reverse direction to the rotation direction in the image forming operation, wherein said voltage selecting device switches the charging voltage applied to said contact-charging member to the second predetermined charging voltage different from the first predetermined charging voltage in the image forming operation by grounding said contact-charging member while said image bearing member is rotating in the reverse direction.

An image forming apparatus having the contact-charging system in which a contact-charging member contacts a surface of a rotatable image bearing member, said image bearing member is charged with said contact-charging member to which a predetermined charging voltage is applied, and said image bearing member can rotate in a reverse direction to a rotation direction in image forming operation, wherein said image forming apparatus comprises:

• a voltage selecting device that switches a voltage applied to said contact-charging member to be different from a voltage in a time period of the image forming operation while said image bearing member is rotated in a reverse direction to the rotation direction in the image forming operation, wherein said voltage selecting device switches the charging voltage applied to said contact-charging member to the second predetermined charging voltage different from the first predetermined charging voltage in the image forming operation by superimposing an AC component on a DC voltage while said image bearing member is rotating in the reverse direction.

An image forming apparatus having the contact-charging system in which a contact-charging member contacts a surface of a rotatable image bearing member, said image bearing member is charged with said contact-charging member to which a predetermined charging voltage is applied, and said image bearing member can rotate in a reverse direction to a rotation direction in image forming operation, wherein said image forming apparatus comprises:

• a voltage selecting device that switches a voltage applied to said contact-charging member to be different from a voltage in a time period of the image forming operation while said image bearing member is rotated in a reverse direction to the rotation direction in the image forming operation, wherein said voltage selecting device switches the charging voltage applied to said contact-charging member to the second predetermined charging voltage different from the first predetermined charging voltage in the image forming operation just after a stopping signal for stopping said image bearing member is transmitted.

An image forming apparatus having a contact-charging system in which a contact-charging member contacts a surface of a rotatable image bearing member, said image bearing member is charged with said contact-charging member to which a predetermined charging voltage is applied, and said image bearing member can rotate in a reverse direction to a rotation direction in image forming operation, wherein said image forming apparatus comprises:

• a voltage selecting device that switches a voltage applied to said contact-charging member to be different from a voltage in a time period of the image forming operation while said image bearing member is rotated in a reverse direction to the rotation direction in the image forming operation, wherein said image bearing member rotates in a reverse direction to a position where a part of the surface of said image bearing member in which the toner is transferred from said contact-charging member passes a cleaning member which cleans the surface of said image bearing member when said image bearing member rotates in a direction reverse to a rotation direction in the image forming operation.