Patent ID: 8483601

Claim:
A transfer fixing device that simultaneously transfers and fixes a toner image onto a surface of a recording medium traveling along a media conveyance path, the device comprising: a transfer fixing member defining a moving surface on which the toner image travels; a pressure member pressed against the transfer fixing member to define a transfer fixing nip where the toner image traveling along the moving surface meets the surface of the recording medium traveling along the media conveyance path; a primary heater located upstream of the transfer fixing nip along the media conveyance path to heat the surface of the recording medium before entering the transfer fixing nip, and a roughness meter disposed along the media conveyance path upstream of the transfer fixing nip and operatively connected with the pressure member to measure roughness of the surface of the recording medium before the recording media enters the transfer fixing nip, and to cause the pressure member to generate the electrostatic field only when the measured roughness exceeds a given upper threshold, the heated surface of the recording medium fusing toner for transfer and fixing into place at the transfer fixing nip, and the pressure member being at least partially electrically biased to generate an electrostatic field to promote transfer of toner at the transfer fixing nip.