Ricoh Company, Ltd.

Yasuharu Kawarasaki

Tomoya Adachi

Hitoshi Fujiwara

Yutaka Naitoh

Tomohiko Fujii

Minoru Toyoda

Masahiro Samei

Shigeo Nanno

Daisuke Inoue

Tetsu Morino

Kenta Kashiwagi

Yutaka Ikebuchi

Takuya Seshita

Naoki Nakatake

Atsushi Takehara

Kohichi Utsunomiya

Kohta Sakaya

Takeshi Yamashita

Seiji Saitoh

Yasuhide Matsuno

Keiji Kunimi

Isamu Kubo

Kyoko Abe

Takahiro Sanada

Rumi Miyazaki

A fixing device includes a rotator, an endless belt, and a nip formation pad. The endless belt contacts the rotator and rotates in a direction of rotation. The nip formation pad contacts an inner circumferential surface of the endless belt to form a fixing nip between the endless belt and the rotator that presses the endless belt against the nip formation pad. The nip formation pad includes a slide layer, a base layer, and a lubricant holding layer. The slide layer contacts the endless belt. The base layer is disposed away from the endless belt. The lubricant holding layer is interposed between the slide layer and the base layer to hold a lubricant inside the lubricant holding layer and supply the lubricant to the slide layer. The slide layer has a porous structure including a plurality of through holes in a thickness direction of the slide layer.

Fixing device including a nip formation pad with a porous structure, and image forming apparatus incorporating same

A fixing device is provided that includes a fixing belt rotatable in a predetermined direction, a heater to heat the fixing belt, a pressure rotator in contact with an outer circumferential surface of the fixing belt, a nip formation pad disposed inside a loop formed by the fixing belt and pressed against the pressure rotator via the fixing belt to form a fixing nip, and a pair of guides in contact with an inner circumferential surface of the fixing belt at both ends of the fixing belt in a width direction thereof, to maintain a substantially cylindrical posture of the fixing belt. Each of the guides includes a guide portion in contact with the inner circumferential surface of the fixing belt and a lubricant holder holding a lubricant that is disposed adjacent to the guide portion and not in contact with the inner circumferential surface of the fixing belt.

Fixing device including a lubricant holder 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

An image forming apparatus includes a controller including a primary heating control portion that determines a first amount of power supplied to a heater based on a temperature of a fixing rotator detected by a temperature detector and controls the heater to perform a primary heating to heat the fixing rotator with the first amount of power, a secondary heating control portion that controls the heater to perform a secondary heating to heat the fixing rotator with a preset second amount of power, and a switch portion that controls the heater to switch between the primary heating and the secondary heating during an identical print job without changing a target temperature of the fixing rotator.

Image forming apparatus and image forming method for controlling a primary heating and a secondary heating of a fixing device

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

An image forming apparatus includes a controller including a primary heating control portion to control a heater to perform a primary heating to heat a fixing rotator with a first amount of power determined based on a temperature of the fixing rotator, a secondary heating control portion to control the heater to perform a secondary heating to heat the fixing rotator with a preset second amount of power, and a switch portion to control the heater to switch between the primary heating and the secondary heating during an identical print job and to perform at least one of a primary switching from the primary heating to the secondary heating and a secondary switching from the secondary heating to the primary heating at a time different from a preset control cycle that defines a power supply time in the primary heating and the secondary heating.

Image forming apparatus with a heater controller and image forming method to control heating

A fixing device includes an endless belt rotatable in a given direction of rotation and a thermal conductor to conduct heat from a heater to the endless belt. A pressure rotator is pressed against the endless belt to form a fixing nip therebetween. An abutment contacts the endless belt to restrict a trajectory of the endless belt to bring the endless belt into contact with the thermal conductor in a particular circumferential span spanning from a particular position upstream from the fixing nip to the fixing nip in the direction of rotation of the endless belt and to separate the endless belt from the thermal conductor in at least a part of an outboard circumferential span outboard from the particular circumferential span in the direction of rotation of the endless belt.

Fixing device and image forming apparatus

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.

Fixing device including a friction reducer and an image forming apparatus including the fixing device

A fixing device includes a fixing rotary body and a pressing rotary body disposed opposite the fixing rotary body. A pivotable pressurization member contacts and presses the pressing rotary body against the fixing rotary body. A pressurization pivot is provided on the pressurization member. A depressurization member, pivotable about the pressurization pivot, causes the pressurization member to isolate the pressing rotary body from the fixing rotary body. A depressurization pivot is provided on the depressurization member. A lock is pivotable about the depressurization pivot and engageable with the pressurization pivot. A biasing member, anchored to the lock, exerts a resilient bias that allows the lock to cause the pressurization member to press the pressing rotary body against the fixing rotary body. A detent is situated in a pivotal trajectory of the lock to restrict pivot of the lock by contacting the lock.

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Osaka, Japan

Yasuharu Kawarasaki