Image forming apparatus

摘要

An image forming apparatus includes an image bearing member; a stretched rotatable belt member; a transfer member for forming a transfer portion for permitting transfer of a toner image from the image bearing member onto a recording material carried on the belt member; a separation roller, capable of separating from the belt member the recording material carried on the belt member, for stretching the belt member; push-up device capable or locally pushing up a belt surface, with respect to a widthwise direction of the belt member, located upstream of the separation roller and downstream of the transfer portion with respect to a rotational direction of the belt member to separate from the belt member the recording material carried on the belt member; a pre-separation charging device, located downstream of the transfer portion and upstream of the push-up means with respect to the rotational direction of the belt member, for electrically charging the recording material by being supplied with a voltage of an identical polarity to a normal charge polarity of a toner; and an execution portion for executing an operation in a mode in which the recording material charged by the supply of the voltage to the pre-separation charging means is separated from the belt member by pushing up the belt member by the push-up device.

主权项

1. An image forming apparatus comprising:
an image bearing member; a stretched rotatable belt member; transfer means for forming a transfer portion for permitting transfer of a toner image from said image bearing member onto a recording material carried on said belt member; a separation roller, capable of separating from said belt member the recording material carried on said belt member, for stretching said belt member; push-up means capable of locally pushing up a belt surface, with respect to a widthwise direction of said belt member, located upstream of said separation roller and downstream of the transfer portion with respect to a rotational direction of said belt member to separate from said belt member the recording material carried on said belt member; pre-separation charging means, located downstream of the transfer portion and upstream of said push-up means with respect to the rotational direction of said belt member, for electrically charging the recording material by being supplied with a bias of an identical polarity to a normal charge polarity of a toner; and an execution portion for executing an operation in a mode in which the recording material charged by said pre-separation charging means is separated from said belt member by pushing up said belt member by said push-up means.