JP2009116040A - Simultaneous transfer and fixing device, and image forming apparatus - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a simultaneous transfer and fixing device which can be reduced in size, and to provide an image forming apparatus using the same. <P>SOLUTION: An electromagnetic induction heating layer 1c of an intermediate transfer belt 1 is formed of a magnetic body, so that a magnetic field H from an exciting coil 4 can be efficiently absorbed. Therefore, a transfer and fixing roller 9 has the exciting coil disposed on the inner circumference of a core part 2 and has an elastic layer 3 which forms a nip part N on the outer circumference of the core part 2. As a result, the simultaneous transfer and fixing device is easily reduced in size, while the elastic layer 3 is disposed to appropriately form the nip part N. <P>COPYRIGHT: (C)2009,JPO&INPIT

Description

  The present invention relates to a simultaneous transfer fixing device for transferring and fixing from the outer peripheral surface of an intermediate transfer belt to the recording material surface and an image forming apparatus provided with the same.

In recent years, as an image forming apparatus represented by an electrophotographic printer, a copying machine, etc., an attempt has been made to reduce the size of the apparatus and cope with high speed by using a simultaneous transfer fixing apparatus using an electromagnetic induction heating system. Yes. For example, an intermediate transfer belt having a conductive layer made of a conductive material such as copper metal as used in Patent Document 1 is used while being supported by a secondary transfer roller so as to be able to move around. An excitation coil that generates a variable magnetic field that penetrates the layer is placed opposite to the secondary transfer roller, and an AC voltage is applied to the excitation coil, and the conductive layer portion through which the variable magnetic field generated from the excitation coil passes is electromagnetically induced by eddy current. Heat is transferred to the surface of the intermediate transfer belt, and the toner image on the intermediate transfer belt is heated and pressed by a pressure roller that is in pressure contact with the secondary transfer roller, and the toner image is transferred onto the recording material. At the same time, there has been proposed a transfer and simultaneous fixing device that fixes the toner at the same time.
JP 2000-275982 A

However, in the one described in Patent Document 1, since an intermediate transfer belt having a conductive layer made of a conductive material such as copper metal is used, the intermediate transfer belt is supported in order to effectively generate heat in the conductive layer. It is necessary to dispose an exciting coil on the secondary transfer roller, and as a result, there is a problem that it is difficult to reduce the size of the simultaneous transfer and fixing device.
SUMMARY An advantage of some aspects of the invention is that it provides a simultaneous transfer fixing device that can be adapted to miniaturization and an image forming apparatus using the same.

In order to solve the above-mentioned problems, an invention according to claim 1 is directed to an intermediate transfer belt including an endless belt having an electromagnetic induction heating layer to which a toner image is transferred to an outer peripheral surface and electromagnetically heated, and the intermediate transfer A transfer fixing roller having an excitation unit that stretches the belt and applies a magnetic field to the intermediate transfer belt, and a pressing unit that presses the transfer fixing roller through the intermediate transfer belt and the recording material, The intermediate transfer belt is heated by the electromagnetic induction heating layer of the intermediate transfer belt that generates heat by the magnetic field from the transfer fixing roller and the pressure applied by the pressurizing unit. In the transfer simultaneous fixing device for transferring and fixing from the outer peripheral surface of the recording material to the recording material surface at the same time, the electromagnetic induction heating layer of the intermediate transfer belt is made of a magnetic material, Shooting fixing roller is provided with the excitation means to the inner periphery of the rotation shaft, characterized in that an elastic layer on the outer periphery of the rotation shaft.
According to a second aspect of the present invention, there is provided the simultaneous transfer fixing device according to the first aspect, wherein the toner image is formed of magnetic toner and is heated and softened by a magnetic field from the transfer fixing roller. To do.
The invention according to claim 3 is the simultaneous transfer fixing device according to claim 1 or 2, wherein the electromagnetic oscillation heating layer of the intermediate transfer belt is made of a magnetic shunt alloy.

According to a fourth aspect of the present invention, in the simultaneous transfer fixing device according to any one of the first to third aspects, the simultaneous transfer fixing device includes an environmental temperature detecting means for detecting an environmental temperature in the device, A control device is provided for controlling the magnetic field strength of the excitation means in the transfer fixing roller in accordance with the environmental temperature detected by the environmental temperature detection means.
According to a fifth aspect of the present invention, in the simultaneous transfer fixing device according to any one of the first to fourth aspects, the simultaneous transfer fixing device detects the temperature of the intermediate transfer belt before the toner image is transferred and fixed. An intermediate transfer belt temperature detecting means is provided, and a control device is provided for controlling the magnetic field strength of the exciting means in the transfer fixing roller in accordance with the temperature detected by the intermediate transfer belt temperature detecting means.
According to a sixth aspect of the present invention, there is provided a photosensitive member, a developing device for supplying toner to the electrostatic latent image formed on the surface of the photosensitive member to form a toner image, and an endless toner image formed on the surface of the photosensitive member. In the image forming apparatus, the image forming apparatus includes: a transfer unit configured to transfer the toner image transferred onto the outer peripheral surface of the intermediate transfer belt; and a transfer simultaneous fixing unit configured to simultaneously transfer and fix the toner image transferred onto the outer peripheral surface of the intermediate transfer belt. The fixing unit is a simultaneous transfer fixing unit according to any one of claims 1 to 5.

  According to the present invention, the electromagnetic induction heating layer of the intermediate transfer belt is made of a magnetic material, and the transfer fixing roller includes the excitation means on the inner periphery of the rotation support shaft, and elastically moves on the outer periphery of the rotation support shaft. By providing the layer, it is possible to provide a simultaneous transfer fixing device that can be adapted to miniaturization and an image forming apparatus using the same.

Hereinafter, embodiments of the present invention will be described in detail with reference to the drawings.
FIG. 1 is a diagram showing a schematic configuration of an image forming apparatus according to an embodiment of the present invention. The image forming apparatus according to the present embodiment includes an endless belt-shaped intermediate transfer belt 1 that is supported so that its peripheral surface is capable of revolving. Yellow, magenta, cyan, and black are disposed at positions facing the intermediate transfer belt 1. Image forming portions 7Y, 7M, 7C, and 7K for forming the toner images are arranged. The image forming units 7Y, 7M, 7C, and 7K are charged to uniformly charge the surfaces of the photoconductors 8Y, 8M, 8C, and 8K around the drum-shaped photoconductors 8Y, 8M, 8C, and 8K that rotate in the direction of the arrow. Device 12, developing devices 13Y, 13M, 13C, 13K, and photoreceptors 8Y, 8M, which store colored toners of yellow, magenta, cyan, and black and supply the respective colored toners to photoreceptors 8Y, 8M, 8C, and 8K Each color of yellow, magenta, cyan, and black is transferred to the surface of the primary transfer device 14 and the photoreceptors 8Y, 8M, 8C, and 8K that transfer the toner images of the respective colors formed on the 8C and 8K to the outer peripheral surface 1a of the intermediate transfer belt 1. Are provided with exposure means 15Y, 15M, 15C, and 15K that form an electrostatic latent image corresponding to each color by irradiating light corresponding to the image information.
Then, an electrostatic latent image corresponding to each color is formed on the surface of the photoconductors 8Y, 8M, 8C, and 8K uniformly charged by the charging device 12 by the exposure means 15Y, 15M, 15C, and 15K. The toner of each color is supplied from the developing devices 13Y, 13M, 13C, and 13K to the image, and the toner image of each color is formed on the photoreceptors 8Y, 8M, 8C, and 8K. The toner images on the photoreceptors 8Y, 8M, 8C, and 8K formed in this manner are transferred onto the outer peripheral surface 1a of the intermediate transfer belt 1 by applying an electric field by the primary transfer device 14. Thereafter, as will be described later, the toner image T on the outer peripheral surface 1a of the intermediate transfer belt 1 is transferred and fixed onto the recording material P such as recording paper by the simultaneous transfer fixing device 17.

The intermediate transfer belt 1 is stretched around a transfer fixing roller 9, a driving roller 10, and a tension roller 11, and is transferred in the arrow A direction by the rotation of the driving roller 10. The toner image T transferred onto the outer peripheral surface 1a of the intermediate transfer belt 1 is melted and softened by electromagnetic induction heating on the transfer and fixing roller 9, as will be described later. Subsequently, the toner image T melted and softened in this way, together with the recording material P guided from the entrance guide 17, is a nip portion N with the transfer fixing roller 9 pressed by the pressure roller 5 as a pressure member. The recording material P is transferred in the direction of arrow B by the outlet guide 18. In this case, since the outer peripheral surface 1a of the intermediate transfer belt 1 has releasability, the toner image T pressurized at the nip portion N is attached and transferred from the outer peripheral surface 1a of the intermediate transfer belt 1 to the surface of the recording material P. However, in order to prevent the toner image T from being smoothly transferred at the nip portion N and to prevent the recording material P from being conveyed along with the intermediate transfer belt 1, a separation claw 19 for separating the recording material P is provided. It has been. In this way, the heated and pressurized toner image T is transferred to the recording material P and is cooled by being separated from the heated intermediate transfer belt 1 and fixed and fixed on the recording material. In the above embodiment, the pressure roller is exemplified as the pressure unit that presses the transfer fixing roller 9. However, the pressure roller is not limited to the pressure roller, and may be a pressure belt using an endless belt. Reference numeral 6 denotes a heat sink means for cooling the intermediate transfer belt 1 heated by the transfer fixing roller 9. This heat sink means 6 is used for intermediate transfer when the toner images of the photoconductors 8Y, 8M, 8C, and 8K are formed on the image forming portions 7Y, 7M, 7C, and 7K, or when the toner images are transferred to the intermediate transfer belt 1. Although it is arranged to suppress the thermal influence by the belt 1, it can be omitted if the thermal influence by the intermediate transfer belt 1 is small.
Further, as shown in FIG. 2, the intermediate transfer belt 1 is formed by forming an electromagnetic induction heating layer 1c made of a magnetic material on a base material 1b made of a film having good heat resistance such as polyester, polyimide, and polyamide. Further, on the electromagnetic induction heating layer 1c, a surface layer 1d having good heat resistance and releasability such as fluororesin, silicone rubber, and fluororubber is formed. Then, the surface of the surface layer 1d becomes the outer peripheral surface 1a of the intermediate transfer belt 1, and as described above, the toner image T is transferred onto the surface layer 1d by the image forming portions 7Y, 7M, 7C, and 7K, and the nip. The toner image T is transferred onto the recording material P at the portion N.

The electromagnetic induction heating layer 1c is made of magnetic stainless steel having a relatively high magnetic permeability, iron-nickel alloy, iron-nickel-chromium alloy, iron-nickel having a required Curie temperature, for example, a Curie temperature lower than the melting temperature of the toner. A magnetic metal such as a magnetic shunt alloy such as a copper alloy or an iron-nickel-molybdenum alloy is formed into a single-layer or multi-layer thin film having a thickness of 1 to 50 μm by vapor deposition, sputtering, or the like. Therefore, the electromagnetic induction heating layer 1c has an eddy current in the electromagnetic induction heating layer 1c when an alternating magnetic field is applied from the excitation coil 4 which is an excitation means built in the transfer fixing roller 9, as will be described later. And the electromagnetic induction superheated layer 1c is heated by this eddy current. In this case, since the electromagnetic induction heating layer 1c is made of the magnetic material as described above, it efficiently absorbs the alternating magnetic field applied from the exciting coil 4. As a result, even if the excitation coil 4 and the electromagnetic induction heating layer 1c are relatively separated from each other, an eddy current can be effectively generated in the electromagnetic induction heating layer. In this case, when a magnetic shunt alloy is used as the electromagnetic induction heating layer 1c, it is preferable to select a magnetic material having a required Curie temperature, so that heating at a temperature higher than necessary is possible.
This eddy current varies depending on the strength and frequency of the alternating magnetic field applied to the electromagnetic induction heating layer 1c. As the strength of the alternating magnetic field is larger and the frequency is higher, a larger eddy current is generated, and the electromagnetic induction heating layer 1c. Can be heated to a high temperature. The strength and frequency of such an alternating magnetic field vary depending on the power and frequency supplied to the excitation coil 4 to be described later, and a larger magnetic field is generated as the power supplied to the excitation coil 4 is increased, and the higher the supply frequency is, the higher the frequency is. The magnetic field is generated. Therefore, when the temperature is high, high frequency high power may be supplied to the exciting coil. In this embodiment, the toner image T is formed by supplying power of 100 to 2000 W and power of 10 to 100 KHz. It is possible to fuse and transfer and fix simultaneously.

The transfer fixing roller 9 has an elastic layer 3 made of an elastic material such as silicone rubber on the outer periphery of a core portion 2 made of a nonmagnetic material such as aluminum or plastic material that constitutes a rotation support shaft that rotates with the transfer of the intermediate transfer belt 1. Is formed. The elastic layer 3 can be deformed by pressing with the pressure roller 5 to form a nip portion N that sandwiches the intermediate transfer belt 1 and the recording material P. Further, on the inner periphery of the core portion 2, an exciting coil 4 that wraps a coil wire 4 b around the center portion of an E-shaped core 4 a made of an iron core or the like and emits a magnetic field in the H direction is attached. The exciting coil 4 is attached to be rotatable in the direction of arrow C within the inner periphery of the core portion 2. In this case, the rotation angle of the excitation coil 4, that is, the radiation direction of the magnetic field H can be set as appropriate by controlling a rotation drive means such as a motor (not shown) that rotates the excitation coil 4. Thus, by rotating the exciting coil 4, the direction of the magnetic field H applied to the electromagnetic induction heating layer 1c of the intermediate transfer belt 1 can be moved closer to or away from the nip portion N. As a result, depending on the transfer speed of the intermediate transfer belt 1, that is, when the transfer speed of the intermediate transfer belt 1 is set to a low speed, the nip portion N approaches the nip portion N. The exciting coil 4 can be rotated so as to be away from it.
Further, around the transfer and fixing roller 9, there are an ambient temperature detection unit 20 that detects the ambient temperature of the image forming apparatus and a temperature that serves as an intermediate transfer belt detection unit that detects the temperature of the intermediate transfer belt 1 before the toner image is transferred and fixed. A sensor 21 is provided. The temperatures detected by the environmental temperature detection means 20 and the temperature sensor 21 are input to the control means 22, and the control means 22 controls the power supply device 23 to control the power and frequency supplied to the excitation coil 4. It is like that. Therefore, in consideration of the temperature detected by the environmental temperature detection means 20 and the temperature sensor 21, the power supplied from the power supply device is controlled by the control means 22 to suppress the supply of useless power and the like to obtain an appropriate heating temperature. It is possible.

  In the simultaneous transfer fixing device in this embodiment, the temperature related to the simultaneous transfer fixing is mainly controlled by the Curie point of the electromagnetic induction heating layer 1 c of the intermediate transfer belt 1. On the other hand, it is useless to apply energy exceeding the Curie point. The amount of energy required for heating the intermediate transfer belt 1 depends on the heat capacity of the intermediate transfer belt 1 and the temperature before heating. Since the heat capacity of the intermediate transfer belt 1 is constant, there is no problem. However, since the temperature before the heating of the intermediate transfer belt 1 changes depending on the situation, it is necessary to grasp the situation of the simultaneous transfer fixing device. That is, it is necessary to control the temperature of heat generated by the electromagnetic induction heating layer 1 c of the intermediate transfer belt 1 according to the environmental temperature of the simultaneous transfer fixing device and the temperature of the intermediate transfer belt 1. Therefore, as described above, the ambient temperature detection means 20 and the temperature sensor 21 detect the ambient temperature outside the simultaneous transfer fixing device and the temperature of the intermediate transfer belt before the toner image is fixed, and based on these detected temperatures. The power of the power supply device 23 that operates the exciting coil 4 is controlled by the control means 22.

  FIG. 3 predicts the amount of energy required for the intermediate transfer belt based on the environmental temperature and the temperature of the intermediate transfer belt 1, and changes the inverter output in the power supply device 23 according to the environmental temperature and the temperature of the intermediate transfer belt 1. It is a table | surface which shows the relationship in the case of. In FIG. 3, when the environmental temperature is less than 17 ° C. and the temperature of the intermediate transfer belt 1 is less than 30 ° C., such as at the start of use of the simultaneous transfer fixing device, the inverter output is maximized to 1200 W. However, as the temperature of the intermediate transfer belt 1 increases with the use of the simultaneous transfer fixing device and the temperature of the intermediate transfer belt 1 becomes 30 to 50 ° C. and 50 ° C. or higher, the inverter output decreases to 1000 W and 800 W. It is clear that this can be achieved. Further, when the environmental temperature is 17 ° C. or higher, it is reduced from the initial inverter output 1200 W, and when the temperature of the intermediate transfer belt 1 is 50 ° C. or higher, it is 750 W, which is greatly reduced from the initial inverter output. It is clear that As described above, the output of the inverter input to the exciting coil 4 is changed as shown in FIG. 5, and a simultaneous transfer fixing device that does not consume more energy than necessary can be obtained.

As described above, since the electromagnetic induction heating layer 1c of the intermediate transfer belt 1 is made of a magnetic material, the magnetic field H from the exciting coil 4 can be efficiently absorbed. Therefore, it is possible to provide the transfer fixing roller 9 in which an exciting coil is provided on the inner periphery of the core portion 2 of the transfer fixing roller 9 and the elastic layer 3 forming the nip portion N is provided on the outer periphery of the core portion 2. became. As a result, it is possible not only to easily reduce the size of the simultaneous transfer and fixing device, but also to form an appropriate nip portion N by arranging the elastic layer 3.
The electromagnetic induction heating layer 1c of the intermediate transfer belt 1 is composed of a thin layer of magnetic metal, and is a magnetic body made of a coating film in which magnetic particles made of these magnetic metals are dispersed in a resin. You can also.

Next, as another embodiment according to the present invention, an example in which a toner image is formed with magnetic toner using the above-described simultaneous transfer and fixing device will be described.
The toner image T on the intermediate transfer belt 1 is softened by heating when it passes through the nip N formed by the transfer fixing roller 9 and the pressure roller 5, and is transferred and fixed by pressure and heat. At this time, the process that softens the toner takes the longest time. For this reason, when the transfer speed of the intermediate transfer belt 1 is increased, it is necessary to widen the width of the nip portion N in order to secure time for softening the toner. As a result, the apparatus becomes larger or the intermediate transfer belt 1 is increased. However, there is an adverse effect of meandering at the wide nip portion N.
In order to compensate for this defect, magnetism is imparted to the toner, and before the toner image T enters the nip portion N, energy is supplied from the exciting coil 4 to cause the toner itself to generate heat and be heated to near the softening point of the toner. As a result, the nip time at the nip portion N can be shortened, and simultaneous transfer fixing at a narrow nip portion is possible.

FIG. 4 is a diagram showing the relationship between the fixing strength of the toner image and the nip time of the nip portion N when the magnetic toner is used (curve 1) and when the non-magnetic toner is used (curve 2). From FIG. 4, it is clear that the nip time required to reach the required fixing strength X is significantly shortened when the magnetic toner is used (t1) compared to when the nonmagnetic toner is used (t2). It is.
In order to shorten the nip time using this magnetic toner, the magnetic field H of the exciting coil 4 needs to reach the toner image T on the intermediate transfer belt 1 effectively. Since the electromagnetic induction heating layer 1c to be absorbed absorbs the magnetic field H, the magnetic field H does not reach the toner image T, the electromagnetic induction heating by the magnetic toner does not occur, and the toner image T cannot be heated. Therefore, a magnetic shunt alloy is used for the electromagnetic induction heating layer 1 c of the intermediate transfer belt 1. Since the magnetic shunt alloy has a characteristic of losing magnetism when it reaches the Curie point, the intermediate transfer belt 1 is sufficiently heated, and when the Curie point is reached, the magnetic field H passes through the intermediate transfer belt 1 and is located on the outer periphery from the intermediate transfer belt 1. The toner image made of magnetic toner can be heated, and this problem can be solved.

In this embodiment, an iron-nickel alloy is used as such a magnetic shunt alloy. The Curie point of the magnetic shunt alloy made of an iron-nickel alloy varies depending on the nickel content ratio, and as shown in FIG. 4, the Curie point tends to increase simply when the nickel content is about 20 to 60%. . Therefore, the extent to which the nickel content is made greatly affects the temperature at the nip portion N. In the case of performing high-speed simultaneous transfer and fixing, the temperature of the nip portion N is set high in order to supply the necessary heat amount in a short transfer and fixing time. For this reason, it is preferable to use an iron-nickel magnetic shunt alloy having a relatively high content even when the nickel content is 50% or less. In this case, when the intermediate transfer belt 1 is a multilayer, the content ratio is determined in consideration of the heat resistance temperature of the layers other than the electromagnetic induction heating layer 1c and the heat resistance temperature of the adhesive used for bonding the magnetic shunt alloy to the other layers. It is necessary to adjust, and considering these points, a nickel content of 40 to 50% is preferable so that a Curie point of 300 to 500 ° C. is obtained.
When such an iron-nickel magnetic shunt alloy having a nickel content of 40 to 50% is used as the electromagnetic induction heating layer 1c, when the electromagnetic induction heating layer 1c generates heat at 300 to 500 ° C., the electromagnetic induction heating layer 1c loses magnetism. The magnetic field H radiated from the exciting coil 4 passes through the intermediate transfer belt 1, and electromagnetically heats the magnetic toner image formed on the outer peripheral surface 1a of the intermediate transfer belt 1. As a result, the magnetic toner image itself generates heat, and the toner image can be melted and softened in a short time by the heat generated by the magnetic toner image itself in addition to the heating by the heated intermediate transfer belt 1. In addition, as the magnetic shunt alloy used in the present invention, in addition to the iron-nickel alloy, iron-nickel-chromium, iron-nickel-copper, iron-nickel-molybdenum and the like can obtain the same characteristics, so that the mechanical strength It can be appropriately selected in consideration of the above.
As described above, as the magnetic toner that generates heat by the magnetic field H radiated from the exciting coil 4, a toner obtained by kneading about 1 to 100 μm of magnetic powder can be used. As the magnetic powder, it is possible to use a magnetic iron oxide such as magnetite, hematite or ferrite, or a magnetic metal such as cobalt or nickel.

As described above, in the present embodiment, since the toner image is formed by the magnetic toner, the toner image itself can be heated by the exciting coil 4, so that the nip for obtaining a predetermined fixing strength is obtained. Time can be shortened.
Further, by using a magnetic shunt alloy as the electromagnetic induction heating layer 1c of the intermediate transfer belt 1, it is possible to sufficiently apply the magnetic field H from the exciting coil 4 to the magnetic toner, and obtain stable heat generation of the toner image. It becomes possible.
Further, by using a magnetic shunt alloy as the electromagnetic induction heating layer 1c of the intermediate transfer belt 1, the heating time of the toner image can be shortened by using both the heat generation of the electromagnetic induction heating layer 1c and the heat generation by the magnetic toner. Accordingly, it is possible to reduce the size of the transfer and fixing roller 9 while suppressing the increase in size of the transfer and fixing roller 9.

1 is a cross-sectional view illustrating a schematic configuration of an image forming apparatus according to an embodiment of the present invention. 1 is a cross-sectional view illustrating a schematic configuration of an intermediate transfer belt used in an image forming apparatus according to an embodiment of the present invention. FIG. 6 is a diagram illustrating a relationship between an inverter output controlled in accordance with an environmental temperature used in an image forming apparatus according to an embodiment of the present invention and a temperature of an intermediate transfer belt. FIG. 6 is a diagram showing a relationship between fixing strength and nip time when magnetic toner and non-magnetic toner used in an image forming apparatus according to another embodiment of the present invention are used. It is a figure which shows the relationship between the Curie point of the iron-nickel magnetic shunt alloy used by the electromagnetic induction heating layer of the intermediate transfer belt used with the image forming apparatus of other embodiment by this invention, and nickel content rate.

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 Intermediate transfer belt, 1a outer peripheral surface, 1b base material, 1c electromagnetic induction heating layer, 1d surface layer, 2 core part, 3 elastic layer, 4 excitation coil, 4a core, 4b coil electric wire, 5 pressure roller, 7Y, 7M 7C, 7K Image forming unit, 8Y, 8M, 8C, 8K photoconductor, 9 transfer fixing roller, 10 driving roller, 11 tension roller, 12 charging device, 13Y, 13M, 13C, 13K developing device, 14 primary transfer device, 15Y, 15M, 15C, 15K Exposure means, 20 Environmental temperature detection means, 21 Temperature sensor, 22 Control means, 23 Power supply

Claims (6)

An intermediate transfer belt composed of an endless belt having an electromagnetic induction heating layer to which a toner image is transferred and heated by electromagnetic induction, and an excitation unit that stretches the intermediate transfer belt and applies a magnetic field to the intermediate transfer belt A transfer fixing roller, and a pressure unit that presses the transfer fixing roller through the intermediate transfer belt and the recording material, and transfers the toner image transferred to the outer peripheral surface of the intermediate transfer belt to the transfer surface. Simultaneous transfer fixing in which fixing is performed simultaneously with transfer from the outer peripheral surface of the intermediate transfer belt to the recording material surface by heating of the electromagnetic induction heating layer of the intermediate transfer belt that generates heat by a magnetic field from a fixing roller and pressurization by the pressing means. In the device
The electromagnetic induction heating layer of the intermediate transfer belt is made of a magnetic material, and the transfer fixing roller includes the excitation unit on the inner periphery of the rotation support shaft and the elastic layer on the outer periphery of the rotation support shaft. A transfer and simultaneous fixing device. In the transfer simultaneous fixing device according to claim 1,
The simultaneous transfer fixing device, wherein the toner image is formed of magnetic toner, and is softened by heat generation by a magnetic field from the transfer fixing roller. In the transfer simultaneous fixing device according to claim 1 or 2,
The simultaneous transfer fixing device, wherein the electromagnetic induction heating layer of the intermediate transfer belt is made of a magnetic shunt alloy. The transfer simultaneous fixing device according to any one of claims 1 to 3,
The simultaneous transfer fixing device includes an environmental temperature detection unit that detects an environmental temperature in the simultaneous transfer fixing device, and a magnetic field of an excitation unit in the transfer fixing roller according to the environmental temperature detected by the environmental temperature detection unit. A simultaneous transfer fixing device comprising a control device for controlling strength. The transfer simultaneous fixing device according to any one of claims 1 to 4,
The simultaneous transfer fixing device includes an intermediate transfer belt temperature detecting unit that detects a temperature of the intermediate transfer belt before the toner image is transferred and fixed, and the transfer fixing is performed according to the temperature detected by the intermediate transfer belt temperature detecting unit. A simultaneous transfer fixing device comprising a control device for controlling the magnetic field strength of the excitation means in the roller. A photoconductor, a developing device that supplies toner to the electrostatic latent image formed on the surface of the photoconductor to form a toner image, and a transfer that transfers the toner image formed on the surface of the photoconductor to an endless intermediate transfer belt And an image forming apparatus including a transfer simultaneous fixing unit that simultaneously transfers and fixes the toner image transferred onto the outer peripheral surface of the intermediate transfer belt to a recording material.
The image forming apparatus according to claim 1, wherein the simultaneous transfer fixing unit is the simultaneous transfer fixing unit according to claim 1.

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