Transfer device and image forming apparatus

A transfer device comprising:

• a transfer unit including:
• a transfer belt for conveying a recording material onto which a toner image is transferred from an image bearing member,
• a transfer roller formed from a resistive material and disposed opposed to the image bearing member across the transfer belt, the transfer roller being in a grounded state in order to cause an electric current to flow from the transfer belt into the transfer roller, and
• a tension roller over which the transfer belt is passed in a tensioned condition, the tension roller being in an electrically floated state;
• a guide member installed in the vicinity of the tension roller for restricting a conveying direction of the recording material conveyed by the transfer belt;
• a first switch for causing the state of the guide member to switch between a grounded state and an electrically floated state;
• a second switch for causing an electric current being made to flow from a power supply section to the transfer roller to switch between a first electric current and a second electric current of which absolute value is smaller than that of the first electric current;
• and
• a control section for controlling the first switch and the second switch depending on a transfer process in which a toner image is transferred from the image bearing member onto the recording material or a cleaning process in which residual toner that is sticking to the transfer belt is caused to adhere onto the image bearing member for its removal, wherein
• the control section, in the transfer process, controls the first switch so that the guide member is in the grounded state while controlling the second switch so that an electric current being caused to flow to the transfer roller becomes the first electric current;
• and, in the cleaning process, controls the first switch so that the guide member is in the electrically floated state while controlling the second switch so that an electric current being caused to flow to the transfer roller becomes the second electric current.