Ricoh Company, Ltd.

Ricoh Corporation

Masanao Ehara

Tadashi Ogawa

Satoshi Ueno

Hiroshi Seo

Takamasa Hase

Hiroshi Yoshinaga

Shuutaroh Yuasa

Motokazu Yasui

Hideo Furukawa

Hirofumi Ogawa

Takahiro Imada

Naoki Iwaya

Yoshiki Yamaguchi

Kenji Ishii

Kazuya Saito

Kensuke Yamaji

Teppei Kawata

Hiroyuki Gotoh

Yutaka Ikebuchi

Takeshi Uchitani

Masahiko Sato

Takayuki Seki

Hiroyuki Shimada

Hiroshi Yokoyama

Shinichi Namekata

Toshiaki Higaya

Keizou Yasuda

Jyunji Nakai

Yuzou Kouno

Masaaki Yoshikawa

Ippei Fujimoto

Akira Shinshi

Yukiko Iwasaki

Shuntaroh Tamaki

Masaharu Furuya

Takayuki Yoshii

Kohji Kamiya

Ippel Fujimoto

Takuya Ejiri

Kenji Ishi

Shuutaro Yuasa

A thermal fixing device includes a fixing member, a flexible endless belt, a flexible endless belt, a rotary pressure member, a heating unit, and a rotation detector. The flexible endless belt is disposed on an outer circumferential surface of the fixing member. The rotary pressure member is disposed parallel to and pressing against the fixing member via the endless belt. The heating unit heats the endless belt. The rotation detector detects a rotation speed of the endless belt. The heating unit is powered off when the rotation speed of the endless belt detected by the rotation detector is at or below a predetermined threshold value.

Thermal fixing device and image forming apparatus including same which detects the speed of a belt on the outer surface of a fixing member

A fixing device includes an induction heater constructed of an exciting coil, a first pair of degaussing coils, and a second pair of degaussing coils. A controller turns off the exciting coil while the controller turns on one of the first pair of degaussing coils and the second pair of degaussing coils and at the same time turns off the other one of the first pair of degaussing coils and the second pair of degaussing coils, and then turns on the exciting coil for an extra time period corresponding to reserved power not supplied to the exciting coil while the exciting coil is turned off.

Fixing device, image forming apparatus incorporating same, and method for heating fixing rotary body

A fixing device includes a fixing rotation body heating and fixing an unfixed image onto a recording medium; a pressing rotation body pressing the recording medium to the fixing rotation body; a first temperature detection unit detecting a temperature of the fixing rotation body; and plural second temperature detection units detecting a temperature of the pressing rotation body. Further the fixing device selects a predetermined second temperature detection unit from the plural second temperature detection units depending on an operation mode of the fixing device, and the fixing device detects the temperature of the pressing rotation body by using the predetermined second temperature detection unit selected by the fixing device.

Fixing device and image forming apparatus

The fixing device using an electromagnetic induction heating (IH) method includes a fixing sleeve having a heating layer, a pressure roller to form a nip while contacting the fixing roller and rotate to drive the fixing sleeve, a temperature detector to detect a temperature on a circumference of the fixing sleeve, and an excitation coil provided near the fixing sleeve and configured to perform induction heating of the heating layer of the fixing sleeve based on the detection result from the temperature detector. The fixing device is configured to change a rotation speed of the fixing sleeve in a standby time during which the fixing sleeve, while rotating, is controlled to be heated so as to maintain a target temperature when a periodic temperature difference occurs on a circumference of the fixing rotary member and having a fluctuation amplitude larger than a predetermined value compared to the target temperature.

A fixing device in an image forming apparatus includes a conveyance member to convey a recording medium at a fixing nip where an image carried on the recording medium is fixed onto it; a plurality of temperature detectors to detect temperature of the conveyance member, the detectors being disposed at both end portions of the conveyance member outside an area where a maximum-sided recording medium passes through; a guide member to guide the recording medium toward the fixing nip; and a guide plate displacing unit to displace a part of the guide member in a direction orthogonal to a conveyed surface of the recording medium to be conveyed at the fixing nip, based on temperature difference detected by the plurality of temperature detectors.

Fixing device, fixing method, image forming apparatus, and image forming method

An image forming apparatus includes a transfer unit, a fuser unit, a detector, and an adjustment mechanism. The transfer unit transfers an image from an imaging surface to a recording sheet passing through a transfer nip. The fuser unit fixes the transferred image in place on the recording sheet passing through a fixing nip. The transfer nip and the fixing nip form part of a sheet feed path along which a recording sheet is fed from the fuser unit to the transfer unit. The detector is located between the transfer nip and the fuser unit, and detects an amount of sheet skew by which the fed recording sheet is deviated from a proper position in the sheet feed path. The adjustment mechanism adjusts position of either or both of the transfer unit and the fuser unit according to the detected amount of sheet skew.

Image forming apparatus having a transfer unit for transferring an image to a recording sheet

A fixing device includes a fixing rotation body heating and fixing an unfixed image onto a recording medium; a pressing rotation body pressing the recording medium to the fixing rotation body; and a temperature detection unit detecting a temperature of the pressing rotation body. Further, when a predetermined time period elapses since a warm-up operation has started before a temperature detected by the temperature detection unit is equal to or greater than a predetermined temperature or when the temperature detected by the temperature detection unit is equal to or greater than the predetermined temperature before the predetermined time period elapses since a warm-up operation has started, the fixing device determines that the warm-up operation is finished.

A fixing device includes a fixing rotary body rotatable in a predetermined direction of rotation to radiate infrared rays; a pressing rotary body, rotatable in a direction counter to the direction of rotation of the fixing rotary body, pressed against the fixing rotary body to form a fixing nip therebetween through which a recording medium bearing a toner image is conveyed; a heater disposed opposite the fixing rotary body to heat the fixing rotary body; a temperature detector spaced apart from the fixing rotary body to detect a temperature of the fixing rotary body based on the infrared rays from the fixing rotary body and disposed below the fixing nip in a vertical direction; and a tube disposed between the fixing rotary body and the temperature detector, the tube through which the infrared rays from the fixing rotary body enter the temperature detector.

Fixing device and image forming apparatus incorporating same having a tube which penetrates through a heater and passes infrared rays to a temperature detector

An elastic layer is provided on a surface of one of a metal core and a substrate. A fixing member and a pressure member press into each other and collectively create a nip therebetween. A toner image is conveyed and fixed when passing through the nip. A thickness of the elastic layer is different in at least two widthwise regions by the same amount from the other region. A pair of edges of a prescribed size of the transfer sheet pass through these two widthwise regions, respectively.

Fixing device and image forming apparatus incorporating the fixing device

A fixing unit includes a fixing member to fuse a toner image on a recording medium on the recording medium; a pressure member to press against the fixing member to define a first nip between the fixing member and the pressure member through which the recording medium is transported; a shifting unit to move the pressure member relative to the fixing member to increase or decrease a pressure of the first nip; a curling correction unit disposed downstream from the first nip in a transport direction of the recording medium that imparts a second curling direction to the recording medium; and a variable setting unit operatively connected to the curling correction unit to variably set an amount of the second curling direction to the recording medium by the curling correction unit depending on the first nip pressure increased or decreased by the shifting unit.

Fixing unit and image forming apparatus

A fixing device includes a fixing member, an induction heating unit, a pressing member, and a damage detection unit. The fixing member heats a toner image on a recording medium to fix the toner image onto the recording medium. The induction heating unit heats the fixing member by electromagnetic induction. The pressing member presses the fixing member to form a fixing nip portion. The fixing member includes a heat insulating elastic layer and a sleeve layer. The sleeve layer is located outside the heat insulating elastic layer and is provided with an outer conductive layer that generates heat from a magnetic flux generated by the induction heating unit. The damage detection unit is connected to the outer, conductive layer.

A fixing device includes a fixing rotary body to rotate in a predetermined direction of rotation and a pressing rotary body pressed against the fixing rotary body to rotate in a direction counter to the direction of rotation of the fixing rotary body and form a nip therebetween through which a recording medium bearing a toner image passes. A heat generator is disposed opposite the fixing rotary body at a section other than the nip to heat the fixing rotary body. A moving assembly is disposed opposite the heat generator to generate a magnetic force to move the heat generator with respect to the fixing rotary body so as to change one of a pressure and a distance between the heat generator and the fixing rotary body.

Fixing device, image forming apparatus incorporating same, and fixing method

A fixing system includes a fixing device that fixes a non-fixed image with heat onto a recording medium. The fixing device includes a fixing roller that generates heat and a pressing roller that presses against the fixing roller. A curl correction device is provided to correct curling of the recording medium passing through the fixing device. The curl correction device includes a heating roller unit that generates heat and an elastic roller that presses against the heating roller unit. A magnetic flux generating device is arranged in the vicinity of the fixing device and the curl correction device and generates magnetic flux.

A fixing device includes a fixing member, a pressure member, and a damage detecting unit. The fixing member includes a heat-insulating elastic layer, to which a conductive thin-film layer is provided. The pressure member presses against the fixing member to form a fixing nip. The damage detecting unit detects the electric resistance of the thin-film layer. The damage detecting unit detects a change in the electric resistance of the thin-film layer, thereby detecting damage to the fixing member. Depending on the extent of the damage, the condition of conveyance of a recording medium to the fixing nip is changed.

Fixing device and image forming apparatus using the same

A fixing device includes an image surface side separating member that separates a recording medium from a fixing member; an image surface side conveyance guiding member arranged downstream of the image surface side separating member; a non-image surface side separating member that separates the recording medium from a pressing member; and a non-image surface side conveyance guiding member arranged downstream of the non-image surface side separating member. When the image surface side conveyance guiding member is rotated about its rotation axis so as to be opened or closed, the image surface side separating member is also rotated or slid so as to be opened or closed simultaneously. When the non-image surface side conveyance guiding member is rotated about its rotation axis so as to be opened or closed, the non-image surface side separating member is also rotated or slid so as to be opened or closed simultaneously.

Growing community of inventors

Kanagawa, Japan

Masanao Ehara