IMAGE FORMING APPARATUS

摘要

An image forming apparatus includes a sheet conveyance passage, a photosensitive drum, a transfer unit, a fixing section, a conveyance unit, one or more detection sensors, an airflow generating section, a cooling airflow passage, and a shielding member. The conveyance unit is at an opposite side of the transfer unit from the photosensitive drum with a predetermined clearance from the transfer unit. Each detection sensor is disposed to face the transfer unit in cross section intersecting the axial direction of the photosensitive drum. The sheet detection sensor performs a predetermined detection. The airflow generating section causes a cooling airflow to flow between the transfer unit and the conveyance unit in the axial direction. The cooling airflow passage guides the cooling airflow toward each detection sensor. The shielding member blocks an airflow from a location around the transfer unit toward the cooling airflow passage in a direction intersecting the axial direction.

主权项

1. An image forming apparatus comprising:
a sheet conveyance passage through which a sheet is conveyed in a predetermined conveyance direction; a photosensitive drum having an axis and a peripheral surface and disposed to face the sheet conveyance passage, the photosensitive drum being configured to axially rotate and bear a toner image on the peripheral surface, a transfer unit including a conveyance belt disposed to face the photosensitive drum across the sheet conveyance passage and to form a nip part with the photosensitive drum, the conveyance belt being configured to circulate, the transfer unit being configured to pass the sheet through the nip part to cause the toner image to be transferred to the sheet; a fixing section disposed downstream from the nip part in the conveyance direction, the fixing section being configured to conduct a fixing process on the sheet to which the toner image has been transferred; a conveyance unit disposed at an opposite side of the transfer unit from the photosensitive drum with a predetermined clearance from the transfer unit, the conveyance unit being configured to convey the sheet having been subjected to the fixing process back into the sheet conveyance passage at a location upstream from the nip part in the conveyance direction; at least one detection sensor disposed in the conveyance unit so as to face the transfer unit in a cross section intersecting an axial direction of the photosensitive drum, the at least one detection sensor being configured to perform a predetermined detection; an airflow generating section configured to cause a cooling airflow to flow between the transfer unit and the conveyance unit in the axial direction; a cooling airflow passage disposed between the transfer unit and the conveyance unit, the cooling airflow passage being configured to guide the cooling airflow toward the at least one detection sensor; and a shielding member disposed in the clearance between the transfer unit and the conveyance unit to extend in the axial direction, the shielding member being configured to block an airflow from a location around the transfer unit toward the cooling airflow passage in a direction intersecting the axial direction.