Sharp Kabushiki Kaisha Corporation

Kazuaki Ishikawa

Kuniaki Nakano

Masashi Hirai

Susumu Murakami

Toshio Yamanaka

Hiroshi Tachiki

Mikio Kakui

Tomomi Tanaka

Yoshiaki Masuda

Masanori Yamada

Takahiko Yoshida

An image forming apparatus includes a transfer belt unit which has an intermediate transfer belt for supporting toner images and primary transfer rollers for pressing the intermediate transfer belt against corresponding photoreceptor drums and moves the intermediate transfer belt along the surface of each photoreceptor drum to transfer the toner images to the intermediate transfer belt. The intermediate transfer belt is formed so as to be 30 &#x3bc;m to 50 &#x3bc;m in average thickness, each primary transfer roller is arranged at a position, along the moving direction of the intermediate transfer belt, which is deviated downstream with respect to the moving direction from the position where the intermediate transfer belt is in contact with the photoreceptor and which is projected toward the photoreceptor drum side so as to press the intermediate transfer belt against photoreceptor with a nip pressure ranging from 10 gf/cmto 40 gf/cm.

Transfer belt unit and image forming apparatus using the same

An ion generating device provided in an image forming apparatus of the present invention as a charging device for charging before a first transfer, a charging device for charging before a second transfer, or a charge device for charging an electrostatic latent image is arranged such that a discharge electrode can move with respect to a dielectric material and the relative positions of the discharge electrode and the dielectric material can be changed. This makes it possible to provide: a long-life ion generating device whose life has been extended by making effective use of a dielectric material; and an image forming apparatus including the ion generating device.

Ion generating device and image forming apparatus including same

A transfer unit includes: an intermediate transfer belt that (i) holds a toner image that has been transferred from a photoreceptor drum and (ii) moves a surface holding the toner image; and a secondary transfer belt that comes into contact with the intermediate transfer belt. The transfer unit (i) transfers the toner image from the intermediate transfer belt to a sheet conveyed to the secondary transfer part and (ii) includes a cleaning unit that removes and collects toner from the surface of the intermediate transfer belt. The transfer unit also includes a power source for sequentially applying, to the secondary transfer belt, (i) a first voltage for generating an electric field that transfers normally-charged toner from the secondary transfer belt to the intermediate transfer belt and (ii) a second voltage for generating an electric field that transfers oppositely-charged toner from the secondary transfer belt to the intermediate transfer belt.

Transfer unit, transfer method, and image forming apparatus

Growing community of inventors

Nara, Japan

Kazuaki Ishikawa