Konica Minolta, Inc.

Konica Minolta Business Technologies, Inc.

Toru Hayase

Naoki Yamamoto

Mamoru Fukaya

Noboru Yonekawa

Koji Yamamoto

Yuusuke Okuno

Hideaki Hayashi

Kentaro Katori

Kuniya Matsuura

Naoki Kataoka

Tomo Kitada

Tsuyoshi Tamaru

Masanori Murakami

Tomohiro Kato

Kanji Nakayama

Taizou Oonishi

Kazunori Nishinoue

Hideaki Ikeda

Norikazu Okabe

Masataka Yagi

Takuya Ishigai

Hiroshi Murasaki

Hiromasa Ueno

Shigeki Yamamoto

Ryuta Akiyama

A fixing device is configured to fix a toner image to a sheet by heat and includes: a heating rotator; a pressurizing roller contacting with the heating rotator; a heater configured to heat the heating rotator such that the heat is transferred to the sheet passing through a contact portion between the heating rotator and the pressurizing roller; a plurality of separation claws configured to separate the sheet from the heating rotator such that the sheet passing through the contact portion is not caught in the heating rotator, the separation claws being provided opposite to the heating rotator; and an adjustor configured to adjust positions of the separation claws relative to the heating rotator such that distances between the separation claws and the heating rotator are equal to each other.

Fixing device having sheet separation members which are displaced by different amounts according to a change in diameter of a heated rotator, and image forming apparatus

A fixing device includes: a fixing rotator; a pressure rotator configured to be pressed into contact with the fixing rotator to form a nip portion; a heating section configured to be provided over an outer circumference of the fixing rotator in a non-contact manner with the fixing rotator and heat the fixing rotator; and a power shutdown section configured to shut down power supply to the heating section when temperature becomes higher than a predetermined setting temperature, wherein the heating section includes an infrared heater and a reflection member which covers the infrared heater and whose portion facing the fixing rotator is an opening portion, a longitudinal length of the reflection member is longer than a length in an axis direction of a light emitting unit of the infrared heater, and a temperature detection unit of the power shutdown section is arranged outside the reflection member.

Fixing device

A fixing apparatus includes: an endless fixing belt; a pad member having a receiving surface and a supported surface; a pressing rotator pressing the fixing belt against the receiving surface and forming a nip portion between an outer circumferential surface of the fixing belt and the pressing rotator; a supporting member supporting the pad member; and a heating source to heat the fixing belt. The supporting member includes a base abutting on the supported surface of the pad member, and an erected wall erected from the base to partition a space inside the fixing belt into an upstream space and a downstream space. The erected wall is disposed upstream or downstream in a recording-material transport direction, from an intermediate position of the nip portion. The heating source is disposed in a larger one of the upstream space and the downstream space.

Fixing apparatus and image forming apparatus

A fixing device thermally fixing an unfixed image by pressing a recording sheet against a heating rotating body using a resistance heating element as a heat source, comprising: a temperature monitoring unit monitoring temperature in a sheet passing region and in a non-sheet passing region of the heating rotating body; a power supply unit supplying power to the resistance heating element so that the temperature in the sheet passing region is maintained at a target temperature during thermal fixing; a cooling unit cooling the non-sheet passing region; and a control unit controlling cooling so that (i) electrical resistivity of the resistance heating element is lower in a region corresponding to the non-sheet passing region than in a region corresponding to the sheet passing region and (ii) an absolute value of a temperature difference between the sheet passing region and the non-sheet passing region does not exceed an allowable temperature difference.

Image forming apparatus with cooling unit for cooling non-sheet passing region

A fixing device having: a fixing member extending in a first predetermined direction; a heating roller extending in the first predetermined direction; a fixing belt stretched between the fixing member and the heating roller and being annular when viewed in a plan view in the first predetermined direction; a heating section heating the heating roller and being provided in the heating roller; a first support section supporting the heating roller in such a manner that the heating roller is movable with respect to the fixing member along a predetermined plane perpendicular to the first predetermined direction; a pressure section exerting a force upon the heating roller in such a direction that the heating roller moves away from the fixing member; and a second support section supporting the heating section in such a manner that the heating section is movable together with the heating roller.

Fixing device having heating section support with hole for releasing heat

A belt-drive device includes a roller, a belt, and a meandering prevention member. The roller is rotatable about an axis. The belt is wound on an outer circumferential surface of the roller. The meandering prevention member is attached to an end of the roller and abuts a side of the belt in the direction of the axis. The meandering prevention member is elastically deformable and has an annular shape. The meandering prevention member has an inner circumferential surface whose diameter is less than an outer diameter of the roller before the meandering prevention member is attached to the roller.

Belt-drive device and image forming apparatus

A fixing device having: a heating unit; a first rotating member and rotating in a first rotational direction; a second rotating member contacting the first rotating member and thereby forming a nip through which a printing medium passes, wherein the second rotating member rotates in a second rotational direction opposite to the first rotational direction; a reflective member provided around the first rotating member and having a reflection surface provided so as to face the first rotating member; and an inhibitory member inhibiting air in a space between the reflective member and the first rotating member from flowing out through a first gap between a downstream end of the reflective member in the first rotational direction and a closest portion of the first rotating member to the downstream end of the reflective member, wherein the inhibitory member overlaps with a part of the first gap.

A fixing device having: a first rotating member rotating in a first rotational direction; a second rotating member contacting the first rotating member and thereby forming a nip through which a printing medium passes, wherein the second rotating member rotates in a second rotational direction opposite to the first rotational direction; a heating unit heating the first rotating member in a heating section not overlapping with the nip when viewed in a plan view in the predetermined direction; and a first reflective member facing at least a part of a portion of the first rotating member that is located on a downstream side in the first rotational direction relative to the heating section but on an upstream side in the first rotational direction relative to the nip, the first reflective member having a reflection surface on the side facing the first rotating member.

A fixing device includes a rotatable fixing belt and a first fixing roller contacting an inner surface of the fixing belt. A second fixing roller contacts an outer surface of the fixing belt to hold the fixing belt against the first fixing roller to define a fixing nip region. An end restriction member supports ends of the fixing belt to restrict its rotation position. A support member is disposed at a position in the end restriction member to pivotally support the first fixing roller. The position is shifted with respect to a center position of the end restriction member corresponding to a rotation center of the fixing belt. The rotation center of the fixing belt is shifted toward a recording-paper conveyance direction of the fixing nip region with respect to a straight line connecting rotation centers of the first and second fixing rollers in a direction orthogonal to their rotation axes.

Fixing device and image forming apparatus having a fixing belt whose rotation center is shifted toward a recording-paper conveyance direction

Image forming apparatus including: fixing device thermally fixing unfixed image on recording sheet by causing recording sheet to pass through nip formed by pressing member pressing against outer circumferential surface of heating rotating body having resistance heating layer; temperature measuring unit measuring temperatures of resistance heating layer in measurement regions set by sectioning outer circumferential surface of heating rotating body along rotational axis; information obtaining unit obtaining information indicating temperature changes in measurement regions in one rotational period of heating rotating body, by sampling measured temperatures; and abnormality judging unit judging whether abnormality has occurred in resistance heating layer based on result of comparison of information that is made between measurement regions in each combination, wherein one or more combinations of measurement regions have been set for each of paper-passing and non-paper-passing regions in nip by using all measurement regions in each of paper-passing and non-paper-passing regions.

Image forming apparatus for detecting abnormality of a fixing device

A fixing device for thermally fixing an unfixed image onto a recording sheet by causing the sheet to pass through a fixing nip. The fixing device includes: heat belt formed in an endless shape and provided with a resistance heat layer; first pressure member provided inside a running path of the heat belt; and second pressure member pressing the first pressure member from over the running path to form the fixing nip. At least one of the first and second pressure members is rotating body. The heat belt has a pressure-receiving area and two non-pressure areas. The pressure-receiving area receives pressures from both the first and second pressure members. The non-pressure areas have been arranged at outside of the pressure-receiving area in an axis direction of the rotating body. Two ring-like electrodes have been formed on circumferential surfaces of the non-pressure areas and are used to supply power to the resistance heat layer.

Fixing device and image forming apparatus

A fixing device for thermally fixing an unfixed image formed on a recording sheet by passing the recording sheet through a fixing nip. The fixing device has a heat-generating endless belt that includes: a resistive heat layer that generates heat upon receiving electric current; and a pair of electrode layers each disposed along a different one of widthwise edges of the heat-generating endless belt. The resistive heat layer has (i) reduced thickness portions each along a widthwise edge thereof and (ii) a middle portion between the reduced thickness portions. Each reduced thickness portion is thinner than the middle portion and connected to the middle portion with a wall surface upright in a direction perpendicular to the rotation axis of the heat-generating endless belt to define a stair shape. Each electrode layer is disposed on the resistive heat layer to be in contact with a corresponding one of the wall surfaces.

Fixing device and image forming apparatus with a mechanism to extend a life of a fixing belt

A fixing device for thermally fixing an unfixed image formed on a recording sheet by passing the recording sheet through a fixing nip. The fixing device has: a heat-generating endless belt having, on a circumferential surface thereof, a sheet passing area through which the recording sheet passes; a first pressure member disposed inside a running path of the endless belt; and a second pressure member disposed to press the endless belt against the first pressure member from outside the running path to form the fixing nip. The endless belt includes: a resistive heat layer that generates heat upon receiving electric current; and a pair of electrode layers that receive electric current. The electrode layers flank the sheet passing area. The resistive heat layer is in contact with the electrode layers at a different one of end faces opposing each other in a width direction of the resistive heat layer.

Fixing device and image forming apparatus with a mechanism to extend life of a fixing belt

Disclosed is a fixing device for thermally fixing an unfixed image onto the recording sheet, the fixing device comprising: a fixing belt; and a meander regulation member provided adjacent to an edge of the fixing belt in a width direction thereof, and operable to prevent meandering of the fixing belt, wherein the fixing belt includes: a resistive heat layer that is tubular and generates heat when an electric current is applied thereto; and first and second electrodes that are provided circumferentially on an outer circumferential surface of the resistive heat layer, and that receive and apply the electric current to the resistive heat layer, and the first electrode is provided closer to the meander regulation member than to the second electrode, and is at a distance from the edge of the fixing belt in the width direction thereof.

A fixing device includes: a heating rotary member having a heating layer generating heat upon current application; a pressurizing rotary member brought into pressure-contact with an outer circumferential surface of the heating rotary member to form fixing nip, through which a sheet on which unfixed toner image is formed passes for heat fixing; circular electrodes that are circumferentially formed at two respective positions sandwiching a sheet passing region therebetween, on the outer circumferential surface, and feed electrical power to the heating layer, the electrodes are each metallic and formed of at least two electrode layers including a first electrode layer layered directly on the heating layer and a second electrode layer as an outermost layer, linear expansion coefficient difference between the first layer and the heating layer is smaller than that between the second layer and the heating layer, and the second layer is more oxidation-resistant than the first layer.

Growing community of inventors

Toyohashi, Japan

Toru Hayase