Ricoh Company, Ltd.

Sanyo Electric Co., Ltd.

Tomohiko Fujii

Minoru Toyoda

Yutaka Naitoh

Tomoya Adachi

Hitoshi Fujiwara

Shigeo Nanno

Yoshihiro Fukuhata

Yasuharu Kawarasaki

Yuusuke Furuichi

Masahiro Samei

Daisuke Inoue

Tamotsu Ikeda

Tetsu Morino

Naoki Nakatake

Hisashi Nakamura

Atsushi Takehara

Kohta Sakaya

Takeshi Yamashita

Masashi Yamamoto

Yasuhide Matsuno

Keiji Kunimi

Isamu Kubo

Kyoko Abe

Takahiro Sanada

Kenta Kashiwagi

Rumi Miyazaki

A fixing device includes a drive roller, a driven roller driven to rotate by the drive roller, and a braking force applicator. The driven roller presses against the drive roller to form an area of contact between the drive roller and the driven roller, through which a recording medium bearing a toner image passes. The braking force applicator applies a braking force to the driven roller to generate a shear force between the drive roller and the driven roller. The shear force acting between the drive roller and the driven roller when the drive roller and the driven roller rotate is in a range of from 15N to 25N.

Fixing device, fixing method, and image forming apparatus

A fixing device includes a fixing belt formed into a loop rotatable in a predetermined direction of rotation and a pressure roller disposed opposite the fixing belt. The pressure roller includes a shaft fixedly positioned and a deformable elastic layer. A fixing pad is disposed inside the loop formed by the fixing belt and separably pressed against the pressure roller via the fixing belt to form a fixing nip between the fixing belt and the pressure roller, through which a recording medium bearing a toner image is conveyed. A biasing member biases the fixing pad and the fixing belt against the pressure roller. A stopper restricts motion of the fixing pad biased by the biasing member. The stopper contacts the fixing pad while the recording medium bearing the toner image is conveyed through the fixing nip.

Fixing device and image forming apparatus

A separator for separating a recording medium from a fixing rotator includes a separation body including a front end and a conveyance path side face. The front end is disposed in proximity to an outer circumferential surface of the fixing rotator. The conveyance path side face faces a conveyance path where the recording medium is conveyed. At least one rotary separation aid projects beyond the conveyance path side face of the separation body toward the conveyance path. The rotary separation aid is rotated by the recording medium as the recording medium comes into contact with the rotary separation aid.

Separator, fixing device, and image forming apparatus

A belt device includes an endless belt and a rotary driver contacting an outer circumferential surface of the belt to drive and rotate the belt. An opposed belt support is disposed opposite the rotary driver and in contact with an inner circumferential surface of the belt. A rotary belt support is disposed opposite the rotary driver via the opposed belt support and in contact with the inner circumferential surface of the belt. A belt support holder holds the opposed belt support and the rotary belt support to retain a predetermined interval between the opposed belt support and the rotary belt support. A biasing assembly presses against the belt support holder to move the opposed belt support and the rotary belt support collectively with respect to the rotary driver and bias the opposed belt support against the rotary driver.

Belt device, fixing device, and image forming apparatus

A fixing device includes a first rotary body, a second rotary body to contact the first rotary body, and a plain bearing that supports the first rotary body or the second rotary body. One rotary body of the first rotary body and the second rotary body has an outer diameter increasing, while the other rotary body has an outer diameter decreasing, in a curved line from an axial center portion to axial end portions of the first rotary body and the second rotary body at least between the first rotary body and the second rotary body. A recording medium passes between the first rotary body and the second rotary body with a circumferential component of a shear force generated between the first rotary body and the second rotary body by use of the plain bearing being in a range of from 15N to 25N.

Fixing device and image forming apparatus incorporating same

A fixing device includes a heat conductor disposed opposite an inner circumferential surface of an endless belt to heat the endless belt. A nip formation pad is disposed opposite the inner circumferential surface of the endless belt and presses the endless belt against a pressing rotary body to form a fixing nip between the endless belt and the pressing rotary body through which a recording medium bearing a toner image is conveyed. A support is disposed opposite an inner circumferential surface of the heat conductor and contacts an abutment face of the nip formation pad to support the nip formation pad against pressure from the pressing rotary body. A heat insulator is interposed between the heater and the nip formation pad and the support to shield the nip formation pad and the support from the heater.

An image forming apparatus includes an image forming device to form a cleaning toner image in a cleaning region on a cleaning sheet and a check toner image in a check region on the cleaning sheet. The image forming apparatus further includes a fixing device including a first rotator and a heater to heat the first rotator to a cleaning temperature that is lower than a fixing temperature to which the first rotator is heated in a print job and higher than a cold offset temperature at which toner adheres to the first rotator by cold offset. Each of the cleaning region and the check region has a length greater than a circumferential length of the first rotator. The cleaning region and the check region are disposed at a leading section and a trailing section of the cleaning sheet in a cleaning sheet conveyance direction, respectively.

Image forming apparatus and image forming method including forming a cleaning toner image

A fixing unit includes an endless belt accommodating a heat source inside a loop formed by the endless belt, a rotary pressing member rotating in contact with the endless belt in a pressure contact section, and a heat transfer member secured to a side plate within the loop of the endless belt to support and heat the endless belt with heat conducted from the heat source. The heat transfer member has an opening opposite the rotary pressing member. A securing member is disposed in the opening of the heat transfer member in pressure contact with the rotary pressing member via the endless belt. The heat transfer member and the securing member collectively include a pair of latching parts to firmly connect the heat transfer member and the securing member with each other when one of the latching parts is fitted to the other one of the latching parts.

Fixing device and image forming apparatus and method of assembling the fixing device

A fixing device fixes a toner image on a recording medium transported to a fixing nip by applying pressure and heat to the recording medium. The fixing device includes an endless belt formed into a loop with both ends bonded together, the belt accommodating a heat source inside thereof, a pressing roller rotating in contact with the endless belt forming the fixing nip between the endless belt and the pressing roller, and a fixed member provided inside a loop of the endless belt to press the endless belt against a pressing roller. A reinforcing member is bonded to the fixed member inside the loop of the endless belt to reinforce the fixed member. A reflector is provided to reflect light emitted from the heat source toward the inner circumferential surface of the endless belt. The reflector is held on the reinforcing member by either plastically or elastically deforming by itself.

Fixing device, image forming apparatus with same, and method of assembling fixing device

A fixing device includes a nip formation pad disposed opposite an inner circumferential surface of an endless belt and a pressing rotary body pressed against the nip formation pad via the endless belt to form a fixing nip between the endless belt and the pressing rotary body, through which a recording medium is conveyed. The pressing rotary body has a diameter increasing from a center to each lateral end in an axial direction thereof. The nip formation pad includes a projection disposed downstream from a rotation axis of the pressing rotary body in a recording medium conveyance direction. The projection projects toward the pressing rotary body in an amount increasing from each lateral end to a center in a longitudinal direction of the nip formation pad parallel to the axial direction of the pressing rotary body.

A fixing unit includes an endless belt unit accommodating a heat source, a pressure roller to rotate in contact with the fixing belt unit forming a pressure border therebetween, and a heat transfer member heated by the heat source to heat the fixing belt unit. The heat transfer member is secured inside an inner circumferential surface of the fixing belt unit and supports the fixing belt unit. A fixed member is secured inside the inner circumferential surface of the fixing belt unit and is pressed against the pressure roller via the fixing belt unit. The heat transfer member has at least one convex portion partially formed in an outer circumferential surface of the heat transfer member in a rotational direction of the fixing belt unit and a longitudinal direction of the heat transfer member to narrow a gap formed between the heat transfer member and the fixing belt unit.

Fixing unit, image forming apparatus incorporating the fixing unit, and image forming method

A fixing device includes a nip formation pad disposed opposite an inner circumferential surface of an endless belt and pressing the endless belt against a pressing rotary body to form a fixing nip between the endless belt and the pressing rotary body. A recording medium is conveyed through the fixing nip. The endless belt slides over a friction reducer sandwiched between the endless belt and the nip formation pad. The friction reducer includes a body and at least one tab projecting from the body in a direction opposite a recording medium conveyance direction. A friction reducer fastener is attached to the tab of the friction reducer and placed inside the nip formation pad to mount the friction reducer on the nip formation pad.

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Hyogo, Japan

Tomohiko Fujii