Patent application number | Description | Published |
20080219721 | Fixing device, image forming apparatus including the fixing device, and fixing method - A fixing device includes a magnetic flux generator, a rotating heat generation member, a magnetic flux adjuster, and a driver. The magnetic flux generator generates a magnetic flux. The rotating heat generation member rotates and applies heat to a recording medium bearing an image, and includes a heat-generating layer to generate heat using the magnetic flux generated by the magnetic flux generator. The magnetic flux adjuster is provided outside the rotating heat generation member, and decreases the magnetic flux applied to the heat-generating layer at least in a desired area in an axial direction of the rotating heat generation member. The driver changes the desired area by driving the magnetic flux adjuster in a direction of rotation of the rotating heat generation member. | 09-11-2008 |
20080226326 | Fixing device, image forming apparatus including the fixing device, and fixing method - A fixing device includes an excitation coil, a heat-generating layer, a magnetic shunt layer, and a degaussing member. The excitation coil generates a magnetic flux. The heat-generating layer generates heat using the magnetic flux generated by the excitation coil. The magnetic shunt layer transmits heat generated by the heat-generating layer. The degaussing member sandwiches the magnetic shunt layer together with the excitation coil, and selectively performs degaussing by generating a repelling magnetic flux for canceling the magnetic flux generated by the excitation coil so as to activate a self-temperature-control function. The degaussing member selectively refrains from degaussing so as to deactivate the self-temperature-control function. | 09-18-2008 |
20090060550 | IMAGE FORMING APPARATUS, FIXING DEVICE, AND HEAT-GENERATING ROTARY MEMBER USING INDUCTION HEATING - An image forming apparatus includes a fixing device for fixing a toner image on a sheet by applying heat, and including an exciting coil and a heat-generating rotary member. The exciting coil generates a magnetic flux. The heat-generating rotary member performs self-temperature control using a repulsive magnetic flux, and includes a degaussing member, a heat-generating layer, a magnetic shunt alloy layer, and a magnetic flux adjuster. The degaussing member generates the repulsive magnetic flux using the magnetic flux generated by the exciting coil. The heat-generating layer generates heat using the magnetic flux generated by the exciting coil. The magnetic shunt alloy layer is disposed between the exciting coil and the degaussing member, and receives heat generated by the heat-generating layer. The magnetic flux adjuster adjusts an amount of the repulsive magnetic flux generated by the degaussing member. | 03-05-2009 |
20100303521 | Fixing device and image forming apparatus incorporating same - In a fixing device, a second rotary member disposed opposite a first rotary member forms a nip between the first rotary member and the second rotary member through which a recording medium bearing a toner image passes. A first separation member rotatively provided on a rotary shaft of the first rotary member separates the recording medium passing through the nip from the first rotary member. A rotation angle adjuster connected to the first separation member changes a rotation angle position of the first separation member. | 12-02-2010 |
20110091253 | Image forming apparatus and fixing device - An image forming apparatus includes an image carrier to carry a toner image and a fixing device to fix the toner image transferred from the image carrier onto a recording medium by applying at least heat to at least one of the toner image and the recording medium. Such a fixing device includes: a magnetic flux generator to generate a magnetic flux; and a heat generating member disposed at least partially in the magnetic flux. The heat generating member includes a heat generating layer to generate heat via eddy currents therein induced by the magnetic flux, magnitudes of the eddy currents varying according to positions thereof in a width direction of the heat generating layer. Included within the heat generating layer is a magnetic layer having a Curie point in a range, e.g., from about 100 degrees centigrade to about 300 degrees centigrade. | 04-21-2011 |
Patent application number | Description | Published |
20080232873 | Fixing device and image forming apparatus including same - An image forming apparatus includes a fixing device to fix a toner image on a recording medium by applying heat. Such a fixing device includes at least a magnetic flux generator, a heat generating roller, a magnetic shunt layer, and a protective layer. The magnetic flux generator is configured to generate magnetic flux. The heat generating roller including a heat generating layer is configured to generate heat by the magnetic flux. The magnetic shunt layer may be formed independently of the heat generating layer. The protective layer is provided on an inner surface of the magnetic shunt layer and configured to cover a crack formed in the magnetic shunt layer during fabrication of the magnetic shunt layer. An image is fixed onto the recording medium by the heat from the heat generating roller. Alternatively, the magnetic shunt layer may be integrally provided with the heat generating layer. | 09-25-2008 |
20090148205 | FIXING DEVICE AND IMAGE FORMING APPARATUS - A fixing device includes a heat applying system having an exciting coil that creates a magnetic flux for generating induction heat in a heat generation layer provided in a fixing roller. Plural demagnetizing coils are stacked in plural layers partially overlying the exciting coil to cancel the magnetic flux at one end of the fixing roller. The plural demagnetizing coils partially overlap each other. | 06-11-2009 |
20090245897 | FIXER, IMAGE FORMING APPARATUS INCLUDING SAME, AND FIXING METHOD - A fixer includes a fixing member provided with a rotary heat generator, a pressure member to form a nip with the fixing member to sandwich the sheet, an excitation coil disposed facing a heat generation layer of the rotary heat generator to generate magnetic flux that inductively heats the heat generation layer, a loop-shaped demagnetization coil unit disposed facing the heat generation layer to generate magnetic flux that partly counteracts the magnetic flux generated by the excitation coil, a first magnetic core disposed in a first area that is enclosed by both the excitation coil and the demagnetization coil unit, and a second magnetic core disposed in a second area that is outside a loop of the demagnetization coil unit and enclosed by the excitation coil. The first magnetic core and the second magnetic core are magnetically continuous in a rotary axial direction of the rotary heat generator. | 10-01-2009 |
20110052277 | FIXING DEVICE AND IMAGE FORMING APPARATUS INCLUDING SAME - A fixing device for fixing an unfixed toner image on a recording medium includes a fixing member, a pressure member, a sheet guide, and a pressure adjusting mechanism. The fixing member heats the unfixed toner image on the recording medium. The pressure member is disposed opposite the fixing member and presses against the fixing member to define a fixing nip through which the recording medium bearing the unfixed toner image passes to fix the unfixed toner image onto the recording medium. The position of the fixing nip is changeable. The sheet guide disposed adjacent to the pressure member guides the recording medium to the fixing nip and moves in conjunction with movement of the pressure member. The pressure adjusting mechanism operatively connected to the pressure member adjusts an amount of engagement of the pressure member relative to the fixing member. An image forming apparatus includes the fixing device. | 03-03-2011 |
20110064450 | Fixing device and image forming apparatus using same - A fixing device includes a heating source; a heating member heated by the heating source; a pressing member contacting the heating member to form a fixing nip therebetween, at which an unfixed image of toner on a recording sheet is fixed to the recording sheet; a first charging member located at an entrance of the fixing device, from which the recording sheet bearing the unfixed toner image enters the fixing device, so as to face the unfixed toner image. The first charging member is not contacted with the heating member and pressing member, and has a charge with a polarity opposite to a polarity of a charge of the toner to collect floating particles of the toner. | 03-17-2011 |
20110064490 | Fixing device and image forming apparatus incorporating the fixing device - 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. | 03-17-2011 |
20110064502 | FIXING DEVICE AND IMAGE FORMING APPARATUS INCORPORATING THE FIXING DEVICE - 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. | 03-17-2011 |
Patent application number | Description | Published |
20110222876 | Fixing device and image forming apparatus using the same - 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. | 09-15-2011 |
20110222926 | Fixing device and image forming apparatus - 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. | 09-15-2011 |
20110229161 | THERMAL FIXING DEVICE AND IMAGE FORMING APPARATUS INCLUDING SAME - 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. | 09-22-2011 |
20110229162 | Fixing device 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. | 09-22-2011 |
20110229178 | FIXING UNIT AND IMAGE FORMING APPARATUS - 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. | 09-22-2011 |
20110229236 | FIXING DEVICE, FIXING METHOD, IMAGE FORMING APPARATUS, AND IMAGE FORMING METHOD - 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. | 09-22-2011 |
20110311284 | FIXING DEVICE, IMAGE FORMING APPARATUS INCORPORATING SAME, AND FIXING METHOD - 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. | 12-22-2011 |
20120207502 | FIXING APPARATUS AND IMAGE FORMING APPARATUS - A disclosed fixing apparatus includes a heat generating layer; an exciting coil; a magnetic shunt layer; a degaussing member; and a magnetic flux adjusting unit. A heat generating rotor is configured with at least the heat generating layer, the exciting coil is arranged outside the heat generating rotor and the degaussing member is arranged inside the heat generating rotor. The fixing apparatus is configured to control a temperature of the heat generating layer with a self temperature control function using a Curie temperature of the magnetic shunt layer which is disposed in an opposing location of the exciting coil. A magnetic path forming member which forms a magnetic path of the exciting coil is arranged on the back face side of the degaussing member that is the reverse side of the magnetic shunt layer with the degaussing member inbetween. | 08-16-2012 |
20120219312 | FIXING DEVICE AND IMAGE FORMING APPARATUS INCORPORATING SAME - 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. | 08-30-2012 |
20130209120 | IMAGE FORMING APPARATUS - Heat-equalizing rotation of a fixing member and a pressing member for equalizing the distribution of the temperature of a surface of the fixing member in a width direction is performed after a recording medium having a size less than or equal to a predetermined size in the width direction passes a nip portion and before a recording medium having a size greater than the predetermined size in the width direction passes the nip portion. Further, a termination condition of the heat-equalizing rotation is selected from among a plurality of different kinds of termination conditions, based on image formation related information related to next image formation performed after the heat-equalizing rotation. | 08-15-2013 |
20130209122 | FIXING DEVICE - A fixing device includes a rotatable fuser member, a rotatable pressure member, a heater, and a controller. The rotatable fuser member is subjected to heating. The rotatable pressure member is disposed opposite the fuser member. The pressure member presses against the fuser member to form a fixing nip therebetween, through which multiple recording media, each spaced apart from each other by an interval distance in a conveyance direction, are sequentially conveyed at a conveyance speed. The heater is disposed adjacent to the fuser member to heat the fuser member. The controller is operatively connected to the heater to control power supply to the heater through a series of on-off switching control cycles, each including an on-time during which the heater power supply is on, and an off-time during which the heater power supply is off, in synchronization with conveyance of the recording medium. | 08-15-2013 |
20130209123 | FIXING DEVICE - A fixing device includes a rotatable fuser member, a rotatable pressure member, a heater, and a controller. The rotatable fuser member is subjected to heating. The rotatable pressure member is disposed opposite the fuser member. The pressure member presses against the fuser member to form a fixing nip therebetween, through which multiple recording media, each spaced apart from each other by an interval distance in a conveyance direction, are sequentially conveyed at a conveyance speed. The heater is disposed adjacent to the fuser member to heat the fuser member. The controller is operatively connected to the heater to control power supply to the heater through a series of on-off switching control cycles, each including an on-time during which the heater power supply is on, and an off-time during which the heater power supply is off, in synchronization with conveyance of the recording medium. | 08-15-2013 |
20130209124 | FIXING DEVICE AND IMAGE FORMING APPARATUS INCORPORATING SAME - A fixing device includes a heating device to heat an endless rotary body with radiant heat, a power source to supply power to the heating device, a first heat source to heat a region on the endless rotary body corresponding to a width of the small size sheet, and a second heat source to heat regions on the endless rotary body corresponding to both widthwise ends of the large size sheet outside the width of the small size sheet. The power source supplies power only to the first heat source when the small size sheet is printed and to both the first and second heat sources when the large size sheet is printed. The power source supplies more power to the first heat source when the small size sheet is printed than when the large size sheet is printed within a maximum power available to the fixing device. | 08-15-2013 |
20130209126 | FIXING DEVICE - A fixing device includes a rotatable fuser member, a rotatable pressure member, a heater, and a controller. The rotatable fuser member is subjected to heating. The rotatable pressure member is disposed opposite the fuser member. The pressure member presses against the fuser member to form a fixing nip therebetween, through which multiple recording media, each spaced apart from each other by an interval distance in a conveyance direction, are sequentially conveyed at a conveyance speed. The heater is disposed adjacent to the fuser member to heat the fuser member. The controller is operatively connected to the heater to control power supply to the heater through a series of on-off switching control cycles, each including an on-time during which the heater power supply is on, and an off-time during which the heater power supply is off, in synchronization with conveyance of the recording medium. | 08-15-2013 |
20130209127 | FIXING DEVICE AND CONTROL METHOD USED THEREIN - A fixing device includes a rotatable fuser member, a rotatable pressure member, a heater, a temperature detector, and a controller. The rotatable fuser member is subjected to heating. The rotatable pressure member is disposed opposite the fuser member. The pressure member presses against the fuser member to form a fixing nip therebetween. The heater is disposed adjacent to the fuser member to heat the fuser member. The temperature detector is directed to at least one of the fuser member, the pressure member, and the heater to detect an operational temperature of the fixing device. The controller is operatively connected to the temperature detector and the heater to control power supply to the heater according to readings of the temperature detector, so as to regulate the detected operational temperature at a setpoint temperature that is variable depending on a print page printed on the recording medium. | 08-15-2013 |
20130209128 | FIXING DEVICE AND IMAGE FORMING DEVICE - When calculating an actual turn-on duty based on a required duty according to a feedback control, the actual turn-on duty is corrected using a correction table or a correction conversion formula such that a required turn-on duty and the actual turn-on duty coincide with each other. A fixing heater is controlled according to the corrected actual turn-on duty. | 08-15-2013 |
20130308990 | FIXING DEVICE AND IMAGE FORMING APPARATUS INCORPORATING SAME - A fixing device includes an endless belt formed into a loop and rotatable in a given direction of rotation. An opposed rotary body contacts the endless belt to form a fixing nip therebetween through which a recording medium bearing a toner image is conveyed. A heater is disposed in proximity to an irradiation span spanning on an inner circumferential surface of the endless belt in a circumferential direction thereof to emit light that irradiates and heats the irradiation span of the endless belt. A shield is interposed between the heater and the irradiation span of the endless belt in a diametrical direction thereof to shield the irradiation span of the endless belt from heated air surrounding the heater. | 11-21-2013 |
20140219672 | FIXING DEVICE AND IMAGE FORMING APPARATUS INCLUDING SAME - A fixing device includes a fixing rotary body, an opposed member, a heater, and a heating controller. The opposed member opposes the fixing rotary body to form a nipping portion therebetween. The heater includes heat generators arranged in a width direction of a recording medium. When the recording medium fed to the nipping portion has an image area and a non-image area, the heating controller controls the outputs of the heat generators based on image information so that a first heat generator of the heat generators corresponding to the image area is higher in temperature and a second heat generator of the heat generators corresponding to the non-image area is lower in temperature. Based on information other than the image information, the heating controller temporarily shifts an area of the fixing rotary body corresponding to the non-image area to a temperature differing from a normal temperature. | 08-07-2014 |
20140219673 | FIXING DEVICE AND IMAGE FORMING APPARATUS INCLUDING SAME - A fixing device includes a rotatable, endless fixing belt; a rotatable contact member configured to contact a circumferential surface of the fixing belt to form a nip in association with the fixing belt; and a heating member disposed at an interior surface of the fixing belt, configured to heat the fixing belt. The heating member includes a multiple heat sources arranged along the width of a sheet of recording media in a direction perpendicular to a sheet conveyance direction. A controller changes an area to be heated by each heat source based on image data and corresponding to an unfixed image on the sheet. The fixing belt is heated by the heating member so that the unfixed image on the sheet that has been conveyed to the nip is fixed onto the sheet at least with heat. The heating member is disposed at a portion other than the fixing nip. | 08-07-2014 |
20140219696 | FIXING DEVICE AND IMAGE FORMING APPARATUS INCLUDING SAME - A fixing device includes a fixing rotary body, an opposed member opposing the fixing rotary body to form a nipping portion, and a heater to heat the fixing rotary body. The heater includes heat generators arranged in a width direction of a recording medium and separately supplied with power. When an unfixed image on the medium has an image area and a non-image area, power supplied to each of the heat generators is controlled so that, of the heat generators, a first heat generator corresponding to the image area becomes a higher temperature and second heat generators corresponding to the non-image area becomes a lower temperature. When the second heat generators are adjacent to each other, power supplied to one of the second heat generators closer to the image area is set to be greater than power supplied to another of the second heat generators farther from the image area. | 08-07-2014 |
20140270822 | IMAGE FORMING APPARATUS AND METHOD OF ARRANGING SHEET DETECTOR - An image forming apparatus includes an image forming device to form a toner image on a recording medium under a prescribed image forming condition, a fixing device to fix the toner image borne on the recording medium thereonto by heating the recording medium based on target fixing temperature, and a detector to detect a type of recording medium. The type is used in setting at least one of the image forming condition and the target fixing temperature. The inequality Tb>Ta is established when Ta represents a time period needed to reach a setting of fixing temperature allocated to the recording medium with its tip detected by the detector after detection of the tip and Tb represents a time period needed for the recording medium with its tip detected by the detector to reach the fixing device after detection of the tip. | 09-18-2014 |
20150071660 | IMAGE FORMING APPARATUS - An image forming apparatus for forming an image on each of recording media includes an optical sensor to irradiate each of the recording media with light to detect smoothness of each of the recording media according to a strength of specularly reflected light of the light with which each of the recording media is irradiated, and a processor to compare the smoothness of the recording media to determine whether a normal image can be formed on one of the recording media having a smoothness detected last. | 03-12-2015 |
20150071661 | IMAGE FORMING APPARATUS - An image forming apparatus includes a conveyance passage unit, a fixing device, an optical sensor, a fixing condition adjuster, and a regulator. A recording medium passes through the conveyance passage unit. The fixing device fixes a toner image onto the recording medium. The optical sensor includes a light-emitting device and a light-receiving device to detect smoothness of the recording medium according to strength of light received. The fixing condition adjuster adjusts fixing conditions according to the smoothness detected. The regulator is disposed in the conveyance passage unit to regulate conveyance of the recording medium, such that at least a part of the recording medium passes through an irradiated area including an intersection that is determined by an emission angle of a first optical axis of light emitted by the light-emitting device and a reflection angle of a second optical axis of light received by the light-receiving device. | 03-12-2015 |