Ricoh Company, Ltd.

Ricoii Company, Limited

Hajime Gotoh

Takahiro Imada

Takuya Seshita

Toshihiko Shimokawa

Masaaki Yoshikawa

Hiroshi Yoshinaga

Kenji Ishii

Hiromasa Takagi

Arinobu Yoshiura

Akira Suzuki

Kensuke Yamaji

Naoki Iwaya

Shuutaroh Yuasa

Tadashi Ogawa

Teppei Kawata

Kazuya Saito

Takamasa Hase

Takeshi Uchitani

Masahiko Satoh

Yuji Arai

Yutaka Ikebuchi

Yoshiki Yamaguchi

Ippei Fujimoto

Tetsuo Tokuda

Takayuki Seki

Ryuuichi Mimbu

Takeshi Yamamoto

Shinichi Namekata

Shuntaro Tamaki

Yasunori Ishigaya

Shuntaroh Tamaki

Ryota Yamashina

Motoyoshi Yamano

Yoshio Hattori

Kohichi Utsunomiya

A fixing device includes an endless belt rotatable in a predetermined direction of rotation and a nip formation assembly disposed opposite an inner circumferential surface of the endless belt. An opposed rotary body is pressed against the nip formation assembly via the endless belt to form a fixing nip between the endless belt and the opposed rotary body through which a recording medium bearing a toner image is conveyed. A belt holder contacts and supports each lateral end of the endless belt in an axial direction thereof. The belt holder is isolated from the opposed rotary body with a first interval interposed therebetween in the axial direction of the endless belt.

Fixing device capable of enhancing durability of endless belt and image forming apparatus incorporating the same

A fixing device includes a driving unit, a pressing roller, a heater, a fixing belt, a pressing roller, a nip formation pad that presses against an inner surface of the fixing belt toward the pressing roller via the fixing belt to form a nip, a separation mechanism, a lubricant between the fixing belt and the nip formation pad, and a processor to execute a warming-up operation of the fixing device. In the warming-up operation, before the heater heats the fixing belt, the separation mechanism moves the nip formation pad in a direction of separating the nip formation pad from the pressing roller to set a nip pressure lower than an ordinary nip pressure, and the driving unit rotates the pressing roller that rotates the fixing belt. Thereafter, the heater starts heating, and the separation mechanism moves the nip formation pad to contact the fixing belt at an ordinary nip pressure.

Fixing device and image forming apparatus incorporating same

A fixing device may include an endless fixing member; a heater inside the fixing member; and a nip forming unit configured to form a nip through which a recording sheet is conveyed, the nip forming unit including a supporting member and a contact member supported by the supporting member, the supporting member including at least one contact surface and the contact member including a plurality of protrusions protruding towards the supporting member such that two or more of the plurality of protrusions are configured to contact one of the at least one contact surface of the supporting member, each of the plurality of protrusions having a height associated there with such that the height of the plurality of protrusions increases in a direction from ends of the contact member towards a center of the contact member.

Fixing device and image forming apparatus

A fixing device includes a fixing rotator unit. The fixing rotator unit includes a fixing rotator formed into a loop; a holder to hold an end in a longitudinal direction of the fixing rotator; a pressure rotator disposed opposite the fixing rotator to press against the fixing rotator; a pressure pad disposed inside the loop to receive pressure from the pressure rotator via the fixing rotator to form an area of contact between the fixing rotator and the pressure rotator; a stay to support the pressure pad against the pressure from the pressure rotator; and a positioner to secure the holder and to position the stay with one end of the stay projecting outwards from the positioner. The positioner has a limited moving distance in a thrust direction. The limited moving distance is shorter than a length of a part of the holder entering the loop.

Fixing device and image forming apparatus for preventing separation of a fixing rotator and a holder

A fixing device includes a heat source; a fixing member looped into a generally cylindrical shape to rotate in a circumferential direction thereof and partially heated by the heat source and to heat a surface of a recording medium bearing an unfixed toner image to fix the unfixed toner image thereon in a fixing process; a rotary pressing member disposed facing the fixing member to form a nip therebetween, through which the recording medium is transported in a transport direction; and a rotation driver to rotate one of the fixing member and the pressing member. In a case in which the fixing member is halted for a reason other than the fixing process while power of the fixing device is on, electric power is not supplied to the heat source and the fixing member is rotated by a predetermined amount or more after the fixing member is halted.

Fixing device and image forming apparatus including same

An image forming apparatus includes a fixing device. The fixing device includes a rotatable endless fixing member, a nip forming member arranged inside the fixing member, a pressing member in contact with the nip forming member via the fixing member, and a heating source configured to heat the fixing member. When an abnormality occurs in at least one of the fixing device and other devices included in the image forming apparatus, a rotation of the fixing member is stopped prior to stopping a rotation driving of a discharging unit and, after stopping, the fixing member is controlled to rotate.

Image forming apparatus

A fixing device includes: a rotatable endless fixing belt; a nip forming member arranged inside the fixing belt; a facing rotating body that abuts the nip forming member via the fixing belt to form a nip portion with the fixing belt; a heat source that directly heats up the fixing belt at a portion other than the nip portion; and a supporting member that supports the nip forming member. The fixing device conveys a recording medium carrying an unfixed image to the nip portion to fix the unfixed image to the recording medium, and the supporting member includes a rising portion extending in an abutting direction of the facing rotating body against the fixing belt and having a tip close to an inner circumferential surface of the fixing belt, and is set to have a section modulus of 200 mmor higher.

A fixing device for fixing an image on a recording medium includes an endless fixing rotary member which is formed into a loop and comes into contact with the image on the recording medium, an opposed rotary member which is in contact with the fixing rotary member, a nip forming member provided inside the loop of the fixing rotary member to be in contact with the opposed rotary member via the fixing rotary member to form a nip portion to which the recording medium is fed in a feeding direction, a support member which supports the nip forming member, and a heating source which heats the fixing rotary member. The nip forming member includes a downstream portion extending downstream in the feeding direction from a center of the nip portion and an upstream portion extending upstream in the feeding direction from the center and longer than the downstream portion.

Fixing device and image forming apparatus including the fixing device

A fixing device includes a fixing rotator, a heat source, a controller, a pressure rotator, and a nip formation pad. The controller controls the heat source such that a temperature of the fixing rotator is equal to a preset fixing temperature. The nip formation pad abuts the pressure rotator via the fixing rotator and forms a nip between the fixing rotator and the pressure rotator. When a print time of a previous job is longer than a prescribed time A and a next job is started within a prescribed time B after an end of the previous job, the controller corrects the preset fixing temperature during a time from a start of the next job to an entry of a print sheet into the nip and during a time from the entry of the print sheet into the nip to a lapse of a prescribed time C after the entry.

Fixing device and image forming apparatus incorporating fixing device

Image forming apparatus including a fixing device that includes a radiant heat heating source and a fixing member that rotates before an abnormality solved

A fixing device in an image forming apparatus includes a rotatable fixing member; a plurality of heat sources to heat each area of the fixing member in a longitudinal direction thereof; a pressure member configured to contact the fixing member and forming a nip in association with the fixing member; a nip forming member disposed inside the fixing member and opposite the pressure member to form a fixing nip; a temperature controller to detect temperature at each area of the fixing member and control the temperature via lighting control performed by the heat sources; and a plurality of temperature sensors to detect temperature of the fixing member or the pressure member in each heating area heated by the plurality of heat sources. When a sheet size set by the image forming apparatus and an actually conveyed sheet size are different, operating speed of the device is adjusted.

A fixing device may include an endless fixing member; a heating unit that is provided inside an inner peripheral surface of the fixing member; and a nip forming unit that comes into press-contact with a rotationally driven pressing member with the fixing member interposed therebetween to form a nip. The nip forming unit has a shape in which a center of a contact surface protrudes toward the pressing member compared to both ends. The nip forming unit has a protruding amount at a center toward the pressing member compared to both ends of the nip forming unit in no-load state is set to be less than a bent amount of the nip forming unit when the nip forming unit comes into press-contact with the pressing member with the fixing member interposed therebetween.

A fixing device includes a fixing rotator, a first heat generator and a second heat generator that heat the fixing rotator, and a support disposed inside the fixing rotator. A reflector, interposed between the support and each of the first heat generator and the second heat generator, reflects light radiated from the first heat generator and the second heat generator toward the fixing rotator. The reflector includes a body mounted on the support and a shield portion projecting from the body toward the first heat generator and the second heat generator to shield the fixing rotator from the first heat generator and the second heat generator. An electric circuit is connected to the first heat generator and the second heat generator. A heat generation restrainer is provided in the electric circuit to restrict heat generation in the electric circuit.

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Kanagawa, Japan

Hajime Gotoh