Sharp Kabushiki Kaisha Corporation

Takahiko Yoshida

Hiroshi Tachiki

Toshiki Takiguchi

Masashi Hirai

Hideshi Izumi

Hiroyuki Murai

Masanori Yamada

Kuniaki Nakano

Norio Tomita

Toshio Yamanaka

Yoshikazu Harada

Yoshiteru Kikuchi

Kohichi Yamauchi

Takashi Makiura

Kenichi Isomi

Kazuaki Ishikawa

In an embodiment of the present invention, an image forming apparatus includes a transfer belt that primarily transfers a toner image formed on a photosensitive drum; a secondary transfer unit including a transfer mechanism portion that secondarily transfers the primarily transferred toner image to a paper; an optical sensor that detects a reference toner image on the transfer belt; and a shutter that protects a detection face of the optical sensor, wherein a separation/contact mechanism portion disposed so as to be brought into contact with both of the shutter and the secondary transfer unit is provided, and the separation/contact mechanism portion allows the shutter to move so as to open and allows the secondary transfer unit to move so as to separate from the transfer belt when the reference toner image is detected by the optical sensor, and allows the shutter to move so as to separate from the transfer belt when the secondary transfer unit is drawn out from an apparatus main body.

Intermediate transfer-type image forming apparatus with separation/contact mechanism

A belt carrying device includes supporting rollers, an endless belt supported by the supporting rollers, and guiding members provided on the endless belt. The endless belt is rotated by rotation of the supporting rollers. An outer peripheral surface of the endless belt is in contact with a cleaning member. The guiding members are provided on those projecting areas of the endless belt, which project in an axial direction of the supporting rollers from both end surfaces of the supporting roller. A guiding member suppresses meandering of the endless belt by coming into contact with an end surface of the supporting roller. Formed on the end, surfaces of at least one of the supporting rollers are projecting sections and groove sections, which are rotated around a rotation axis of the at least one of the supporting rollers in response to rotation of the at least one of the supporting rollers.

Belt carrying device, intermediate transfer device, and image forming apparatus

A belt transfer device according to the present invention includes an intermediate transfer belt, a transfer member, a shifter, a detector, and a controller. The transfer member primarily transfers a toner image from an image carrier to the intermediate transfer belt. The shifter reciprocates in specified opposite directions so as to shift the transfer member between a transfer position where the transfer member is in compressive contact with the inner surface of the intermediate transfer belt and a home position where the transfer member is away from the belt surface. The detector outputs a signal representing the position of the shifter. Based on the state of the signal output from the detector while the shifter is reciprocating each time in the opposite directions, the controller determines whether the tensile force of the intermediate transfer belt is proper.

Belt transfer device

A transfer device includes a transfer device controller for controlling the whole transfer device, a storage for storing various kinds of data etc. necessary for control, an intermediate transfer unit including a primary transfer power supply and its driver, a secondary transfer unit including a secondary transfer power supply and its driver, and a PTC unit. In the transfer device, a controller communicates with a main controller that controls the whole image forming apparatus, and acquires, for example, information on the total print count or the like. When PTC radiation is determined to be needed based on the above information, the controller controls to drive the PTC unit.

Transfer device and image forming apparatus using the 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

A transfer belt device includes an endless transfer belt that is tightly stretched by a plurality of rollers and forms a transport path where a recording medium or a developer image is transported facing a monochrome image bearing member and a plurality of color image bearing members arranged in parallel along a fixed direction. In the apparatus, a first transfer unit having a first linking member in which a monochrome-image transfer member is supported that transfers a developer image formed on the monochrome image bearing member onto a recording medium or an outer peripheral surface of the belt, and a second transfer unit having a second linking member in which a plurality of color-image transfer members are supported that transfer developer images formed on the respective color image bearing members onto a recording medium or an outer peripheral surface of the belt, are linked via the first and second linking members.

Growing community of inventors

Nara, Japan

Takahiko Yoshida