Minolta Camera Kabushiki Kaisha

Yoshinobu Hara

Kazuyoshi Hara

Shizuo Yuge

Masataka Oda

An image forming apparatus wherein toner images formed on a photosensitive member are transferred to a transfer medium and overlaid thereon, and the toner images on the transfer medium are transferred onto a copy sheet. The apparatus has a charger for reducing charge on the toner images transferred to the transfer medium, and output of the charger is controlled in accordance with the number of toner images on the transfer medium. Alternatively, the image forming apparatus has a first charger for reducing charge on the toner images transferred to the transfer medium and a second charger for recharging the toner images processed by the first charger.

Image forming method and image forming apparatus, including means for

An image forming apparatus wherein a toner image formed on a photosensitive member or a toner image once transferred therefrom to a transfer belt is transferred onto a copy sheet by a transfer charger, and the output of the transfer charger is controlled so as to apply a specified amount of charge to the copy sheet for fine image transfer. Specifically, an electric current flowing in the copy sheet is estimated based on an electric current flowing in the transfer belt when no sheets are on the belt, and the output of the transfer charger or alternatively a bias voltage impressed on a roller which supports the transfer belt is controlled so as to cause a specified value of electric current to flow in the transfer belt.

Control means for a transfer charger in an image forming apparatus

A sheet guiding apparatus and an image forming apparatus incorporating same. The copy sheet being transported to the transfer station by a pair of feed rollers is guided by a pair of guide panels arranged in one direction and an opposite direction. These guide panels are located in an extension state with a substantial intervening spacing at the moment transport starts, and are located in a contracted state with a narrow intervening spacing at the completion of sheet transport so as to prevent transport error and transfer dislocation. The timing by which the guide panels change form the extension state to the contraction state changing in accordance with the copy sheet size to assure guidability regardless of the size of the copy sheet.

Sheet guiding apparatus and an image forming apparatus using same

A transfer belt for use in an electrophotographic image forming apparatus is so arranged as to pass through a gap between a photoconductor and a transfer charger provided opposite to the photoconductor, and a second transfer charger is arranged outside the transfer belt at the downstream of a first transfer charger in the transporting direction of the transfer belt. The first transfer charger transfers an image on the photoconductor onto the transfer belt or onto the surface of a transfer material being properly transported thereto, while the second transfer charger transfers a transferred image on the transfer belt onto the back of the transfer material being transported on the transfer belt thus enabling to form an image only on one side or on both sides of the transfer material.

Growing community of inventors

Shinshiro, Japan

Yoshinobu Hara