Heat fixing device having cooling fan and pressing roller with heat conductive filler

摘要

A heat fixing device includes a rotatable member for heating, a pressing roller configured to form a fixing nip portion that nips and conveys a recording material bearing a toner image, and a cooling fan configured to cool a recording material non-passing region in the rotatable member for heating in a direction orthogonal to a recording material conveying direction, wherein the pressing roller includes a rubber layer, between a cored bar and a release layer, containing a needle-shaped heat conductive filler oriented in a roller axis direction.

主权项

1. A heat fixing device comprising:
a rotatable member; a pressing roller configured to form a fixing nip portion that nips and conveys a recording material bearing a toner image, the pressing roller including a core bar and a rubber layer outside the core bar; and a cooling fan configured to blow air to a paper non-passing region of the rotatable member, wherein the rubber layer contains a needle-shaped heat conductive filler oriented in a roller axis direction, and wherein the cooling fan blows air to the paper non-passing region of the rotatable member so that heat quantity flowing, through the rubber layer, from the paper non-passing region of the rotatable member to a paper passing region of the rotatable member is substantially equal to heat quantity removed from the paper passing region by blowing of the cooling fan.