JPH10171276A - Image heating fixing device and image forming device - Google Patents

Abstract

(57) [Problem] To provide an image heating / fixing apparatus capable of replacing only a fixing film having the shortest life in an image heating / fixing apparatus, so that other still-life parts can be used as they are. It is an object of the present invention to provide an image heating / fixing device and an image forming apparatus having the same. A pressure roller (12) pressed against a fixing film (13).
After the retraction, the fixing film 13 whose life has expired is detached from the coil unit 14 and taken out from the image heating fixing device 9. After a new fixing film 13 is fitted and inserted into the coil unit 14, the pressure roller 12 is moved to the fixing film 13.
It is characterized in that it is configured to return to a state in which it is pressed against the.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention is used in an image forming apparatus such as an electrophotographic apparatus and an electrostatic recording apparatus, and generates an eddy current using electromagnetic induction and heats the eddy current. And an image fixing device for fixing an unfixed toner image.

[0002]

2. Description of the Related Art A contact heating system such as a heat roller system or a film heating system has been widely used as an image heating and fixing apparatus. Among them, in a color image heating and fixing apparatus having a maximum of four toner layers, a halogen heater is heated to heat and fix a toner image via a core metal of a fixing roller and a rubber elastic layer.

For example, in the technique disclosed in Japanese Patent Publication No. 5-9027, an eddy current is generated in a fixing roller by magnetic flux,
It has been proposed to generate heat by Joule heat.
By utilizing the generation of the eddy current in this way, the heat generation position can be made as close to the toner as possible, and the energy consumption can be made more efficient than the heat roller using a halogen lamp.

However, in the above-described fixing method, it is necessary to heat a fixing roller having a relatively large heat capacity, so that even a relatively efficient one cannot perform a quick start. According to the technology disclosed in Japanese Patent Publication No. 5-9027, when eddy current is generated in a cylindrical body to generate Joule heat, the temperature of the exciting coil and the exciting core increases, and the amount of magnetic flux decreases. The fever was unstable. Also,
Thermal efficiency was not sufficient due to heat radiation inside the roller.

[0005] Other methods using a halogen heater include:
Since electric energy is once converted into light energy and used, there is also a problem that the energy conversion efficiency is poor.

Further, in a color image forming apparatus, up to four toner layers may be superimposed. In this case, if the interface between the recording material and the toner layer is not sufficiently heated, defective fixing may occur. is there.

For this reason, in the color roller fixing, a halogen heater is also provided on the pressure roller side.
Even so, there is a drawback that a quick start cannot be realized, and in such a configuration, there is a drawback that power consumption is increased due to a large heat capacity of the pressure roller.

An example of a conventional image heating and fixing apparatus which solves the above problem will be described with reference to FIGS. The image heating and fixing apparatus 101 shown in FIG. 12 is disposed downstream of the nip between the photosensitive drum 102 serving as an image forming unit and the transfer roller 103 as shown in FIG. And a pressure roller 105 disposed below the conveying path of the recording material P.

As shown in FIG. 13, a heating roller 104 has a rubber layer 106b on the outer surface of a cylindrical nickel electroformed film 106a.
And a fixing film 106 formed by forming a Teflon layer 106c on the outer surface of the rubber layer 106b.
The coil 108 and the core 109 supported by the
A high-frequency current flows through the core 109 to generate an alternating magnetic flux, and an eddy current is generated in the nickel electroformed film 106a to generate Joule heat.
4, unfixed toner T ₁ of the on the recording material P transported through the nip portion N between the pressure roller 105 is pressed against the heating roller 104 is heated and pressurized fixed toner T ₂ of the FIG. 13 The toner is fixed as described above and discharged outside the machine.

[0010]

However, in the above-mentioned prior art, there is a problem that the nickel electroformed film 106a has poor durability, and the fixing film 106 is broken with a maximum durability of 400,000 pages. If the fixing film 106 breaks, a service person will ask the image heating fixing device 10
1 was completely removed from the image forming apparatus main body, and was replaced with a new image heating and fixing apparatus 101.

In this case, the coil 10 which is still sufficiently usable
8, the core 109 and the pressure roller 105
Since it was exchanged as a unit, it was used inefficiently in terms of saving resources. These problems are reflected in the cost of the image heating and fixing apparatus 101, and the image heating and fixing apparatus
This was one of the reasons that the cost of 101 could not be reduced.

The present invention has been made to solve the above problems, and
The purpose is to replace only the fixing film with the shortest life in the image heating and fixing device so that other parts with a long life can be used as they are to reduce costs and save resources. And an image forming apparatus provided with the same.

[0013]

A typical configuration according to the present invention for achieving the above object is that an unfixed toner image is formed by a pressing member and a rotating body opposed to the pressing member. The recording material is nipped and conveyed, and is located on the opposite side of the unfixed toner image on the recording material with the rotating body therebetween, and
At least one excitation coil for generating an alternating magnetic field;
An image heating / fixing apparatus having a heat generating section for generating Joule heat by an eddy current generated by the exciting coil, wherein the rotating body is detachable from a main body of the image heating / fixing apparatus. It is.

Since the present invention is constructed as described above, when the rotating body (fixing film) having the shortest life in the image heating fixing device is broken, only the rotating body is detached from the image heating fixing device main body. Can be replaced, and other parts having a still life can be used as they are, so that the cost of the image heating and fixing apparatus can be greatly reduced.

[0015]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS Referring to the drawings, an embodiment in which the present invention is applied to an electrophotographic color printer as an example of an image heating / fixing apparatus according to the present invention and an image forming apparatus provided with the apparatus will be specifically described. FIG. 1 is a schematic cross-sectional explanatory view showing a configuration of a recording unit and a fixing unit of an image forming apparatus provided with an image heating and fixing apparatus according to the present invention, and FIG. 2 is a configuration of a first embodiment of an image heating and fixing apparatus according to the present invention. 3 is a side view showing the configuration of the first embodiment, FIG. 4 is a front explanatory view showing the configuration of the first embodiment, FIG. 5 is a side sectional explanatory view showing the configuration of the first embodiment, FIG. 6 is a cross-sectional view showing the configuration of the exciting coil, and FIG. 7 is a diagram showing the layer structure of the rotating body of the first embodiment.

In FIG. 1, reference numeral 1 denotes an electrophotographic photosensitive drum serving as an image forming means composed of an organic photosensitive member, an amorphous silicon photosensitive member, or the like; and 2, a photosensitive drum 1 for uniformly charging the photosensitive drum 1 Charging roller.

Reference numeral 3 denotes a laser optical box that converts a signal from an image signal generator (not shown) into laser light on / off and forms an electrostatic latent image on the surface of the photosensitive drum 1. Reference numeral 4 denotes a laser beam, and reference numeral 5 denotes a mirror for reflecting the laser beam 4 emitted from the laser optical box 3 and guiding it to the photosensitive drum 1.

The electrostatic latent image on the photosensitive drum 1 is visualized by the toner being selectively adhered by the developing unit 6.
The developing device 6 includes a yellow Y, magenta M, and cyan C color developing device and a black Bk developing device. The developing device 6 develops a latent image on the photosensitive drum 1 one by one, and transfers the toner image to the intermediate transfer drum 7. A color image is obtained by successively superimposing the color images.

The intermediate transfer drum 7 has a medium-resistance elastic layer and a high-resistance surface layer on a metal drum. A bias potential is applied to the metal drum to transfer a toner image by a potential difference from the photosensitive drum 1. Is what you do.

On the other hand, a recording material P sent out by a feed roller from a feed cassette (not shown) is transferred to a transfer roller 8 serving as a conveying means and an intermediate transfer drum so as to synchronize with the electrostatic latent image on the photosensitive drum 1. 7 is fed into the nip. Then, the transfer roller 8 transfers the toner image on the intermediate transfer drum 7 onto the recording material P by supplying a charge having a polarity opposite to that of the toner from the back surface of the recording material P.

The unfixed toner image transferred onto the recording material P in this manner is heated and pressed by the image heating / fixing device 9 to be permanently fixed on the recording material P, and then to a discharge tray (not shown). Is discharged.

The toner, paper dust and the like remaining on the photosensitive drum 1 and the intermediate transfer drum 7 are removed by cleaners 10 and 11, respectively, and the photosensitive drum 1 repeats the above-mentioned steps after charging.

Next, the structure of the image heating and fixing device 9 will be described in detail with reference to FIGS. In the figure, an image heating and fixing device 9 includes a pressing roller 12 serving as a pressing member disposed below a conveying path of the recording material P, and a conveying path of the recording material P facing the pressing roller 12. And a cylindrical fixing film 13 serving as a rotating body disposed on top of the fixing film.
Inside the cylinder 13, a cylindrical coil unit 14 is arranged.

As shown in FIGS. 5 and 7, the fixing film 13 has an elastic layer 13b provided on an outer surface of a cylindrical heat generating layer 13a, and a release layer 13c provided on an outer surface of the elastic layer 13b. Molded.

The inner diameter of the fixing film 13 is a coil unit.
The fixing film 13 is configured to be larger by a predetermined dimension than the outer diameter of the fixing unit 14, and the fixing film 13 is slidably fitted to the coil unit 14 fixed to the main body of the image heating fixing device 9. . Therefore, the fixing film 13 pressed against the rotationally driven pressure roller 12 slidably rotates with respect to the fixed coil unit 14, and
And rotate together.

Inside the coil unit 14, a holding member 14a made of a liquid crystal polymer for holding an exciting coil 15 made of a heat-resistant wire for generating an alternating magnetic field is integrally formed. A high magnetic permeability core 16 is built in the holding member 14a. The excitation coil 15 is wound around the holding member 14a in one or more rows.

The pressure roller 12 is pressed against the fixing film 13 to form a nip portion N with the fixing film 13, and at the same time,
The fixing film 13 is rotated in the direction indicated by the arrow b in FIG. 5, rotates the fixing film 13 relative to the coil unit 14 in the direction indicated by the arrow a in FIG. 5, and conveys the outer surface of the fixing film 13 in the direction indicated by the arrow a in FIG. Further, the fixing film 13 is pressed by a coil unit 14 which also serves as a guide for the fixing film 13.
The transfer stability to the nip portion N with the transfer roller 12 and the pressing of the fixing film 13 by the pressure roller 12 are achieved.

The pressure roller 12 is a metal core 12a made of iron or the like.
And an elastic member 12b provided on the outer periphery of the cored bar 12a and coated with a silicone rubber or a fluorine rubber having a thickness of 3 mm. The pressure roller 12 is driven to rotate in the direction of arrow b in FIG. 5 by a drive mechanism (not shown). 1 shown in FIG.
Reference numerals 7 and 18 denote thermistors for measuring the surface temperatures of the pressure roller 12 and the fixing film 13, respectively.

The high magnetic permeability core 16 is preferably made of a material used for a transformer core such as ferrite or permalloy. More preferably, it is preferable to use ferrite which has a small loss even at 100 kHz or more.

An excitation circuit (not shown) is connected to the excitation coil 15, and this circuit can generate a high frequency of 20 kHz to 500 kHz by a switching power supply. Performing heat fixing by passing the recording material P carrying the unfixed toner T ₁ to the nip portion N formed between the pressing roller 12 with the fixing film 13.

The principle of heating at the nip N is that the magnetic flux generated by the current applied to the exciting coil 15 by an exciting circuit (not shown) is guided to the high magnetic permeability core 16 to fix the fixing film.
An eddy current is generated in the heat generating layer 13a serving as the heat generating portion of the device 13. Joule heat is generated by the eddy current and the specific resistance of the heat generating layer 13a.

The generated Joule heat is applied to the elastic layer 13b and the release layer.
Heating the unfixed toner T ₁ of the on the recording material P and該被recording material P conveyed through the nip portion N via 13c. Nip part N
Melting the unfixed toner T ₁ is the inner, a permanent fixed image is cooled fixing toner T ₂ after passing through the nip portion N.

In order that the magnetic field generated by the excitation coil 15 and the high magnetic permeability core 16 be efficiently absorbed by the heat generating layer 13a of the fixing film 13, the excitation coil 15 and the high magnetic permeability core 16 and the heat generating layer of the fixing film 13 The separation distance from 13a should be as short as possible. That is, the high permeability core 16 and the exciting coil 15
This is because the magnetic flux absorption efficiency is higher when the distance between the heat generating layer 13a and the heat generating layer 13a is reduced as much as possible.

The holding member 14a is made of a material that can sufficiently withstand sliding friction between the fixing film 13 and the heat generating layer 13a. Further, grease for lubrication is applied to the inside of the fixing film 13, so that smooth rotation can be performed.

FIG. 6 is a sectional view of a heat-resistant electric wire constituting the exciting coil 15. This heat resistant wire is a super heat resistant wire,
A ceramic 15b is provided on the outer periphery of the nickel-plated copper conductor 15a, and a polyimide 15c is further provided on the outer periphery of the ceramic 15b.
Is provided. With this configuration, the exciting coil 15
It can withstand high temperatures up to about 65 degrees.

The conductive heat generating layer 13a of the fixing film 13 may be made of a non-magnetic metal, but more preferably a metal having good magnetic flux absorption, such as nickel, iron, magnetic stainless steel, or a cobalt-nickel alloy. It is preferable that the thickness is greater than the skin depth σ represented by the following formula and 200 μm or less.

Here, the skin depth σ [m] depends on the frequency f [Hz] of the excitation circuit, the magnetic permeability μ, and the specific resistance ρ [Ωm].
Is expressed as {σ = 503 × (ρ / fμ) ^1/2 }.

This indicates the depth of penetration of an electromagnetic wave used in electromagnetic induction. At a depth deeper than this, the intensity of the electromagnetic wave becomes less than {1 / e (e is a natural number base)} of the surface. Conversely, most energy is absorbed to this depth.

Preferably, the heat generating layer 13a of the fixing film 13
Is preferably 1 to 100 μm. If the thickness of the heat generating layer 13a is smaller than 1 μm, most of the electromagnetic energy cannot be absorbed, so that the efficiency is deteriorated. On the other hand, if the heat generating layer 13a exceeds 100 μm, the rigidity becomes too high and the flexibility deteriorates, which is not practical for use as a rotating body.

The elastic layer 13b is made of a material having good heat resistance and good thermal conductivity, such as silicone rubber, fluorine rubber, fluorosilicone rubber, or the like. The thickness of the elastic layer 13b is 10
~ 500 µm is preferred. This is the thickness required to ensure the quality of the fixed image.

When a color image is printed, a solid image is formed over a relatively large area on the recording material P, especially for a photographic image. In this case, if the release layer 13c, which is the heating surface, cannot follow the unevenness of the recording material P or the unevenness of the toner layer, uneven heating will occur, and uneven gloss will occur in the image in the portion where the amount of heat transfer is large and the portion where the amount is small. That is, a portion having a large amount of heat transfer has high gloss, and a portion having a small amount of heat transfer has low gloss.

Therefore, the thickness of the elastic layer 13b is 10
If the thickness is less than μm, the unevenness of the recording material P or the toner layer cannot be completely followed, and image gloss unevenness occurs. Also elastic layer
When the thickness of the elastic layer 13b is 1000 μm or more, the thermal resistance of the elastic layer 13b becomes large, and it is difficult to realize a quick start. Therefore, the thickness of the elastic layer 13b is more preferably 50
~ 500 µm is good.

On the other hand, if the hardness of the elastic layer 13b is too high, the unevenness of the recording material P or the toner layer cannot be completely followed, and image gloss unevenness occurs. Therefore, the hardness of the elastic layer 13b is preferably 60 ° (JIS-A) or less, more preferably 45 ° (JIS-A) or less.

The thermal conductivity λ of the elastic layer 13b is 6 × 10 ^-4 to
2 × 10 ⁻³ [cal / cm · sec · deg] is good. When the thermal conductivity λ is smaller than 6 × 10 ⁻⁴ [cal / cm · sec · deg], the thermal resistance is large, and the temperature rise in the surface layer of the fixing film 13 is slow. Also, the thermal conductivity λ is 2 × 10
If it is larger than ^-3 [cal / cm.sec.deg], the hardness becomes too high or the compression set becomes worse. More preferably, the thermal conductivity λ is 8 × 10 ^{−4 to} 1.5 × 10
^-3 [cal / cm-sec-deg] is good.

The release layer 13c is made of fluororesin, silicone resin, fluororesin silicone rubber, fluororubber, silicone rubber, PFA (tetrafluoroethylene / perfluoroalkyl ether copolymer / 4-tetrafluoroethylene / perfluoroalkylvinyl ether copolymer). Polymerized resin), PTF
Good releasability and heat resistance such as E (polytetrafluoroethylene / 4-fluoroethylene resin), FEP (tetrafluoroethylene / hexafluoropropylene copolymer / tetrafluoroethylene / hexafluoropropylene copolymer resin) Select a material.

The thickness of the release layer 13c is preferably 1 to 100 μm. If the thickness of the release layer 13c is less than 1 μm, problems such as formation of a portion having poor release properties due to coating unevenness of the coating and insufficient durability occur. On the other hand, if the release layer 13c exceeds 100 μm, there is a problem that heat conduction is deteriorated. In particular, in the case of a resin-based release layer, the hardness becomes too high, and the effect of the elastic layer 13b is lost.

In this embodiment, the fixing film 13 pressed against the pressure roller 12 is pressed in the direction of the arrow a in FIG. 5 by the pressure roller 12 which is rotated in the direction of the arrow b in FIG. Although it is configured to rotate,
As another configuration, tension may be applied to the fixing film 13 by a tension roller, and the fixing film 13 may be rotationally driven by a driving roller (not shown).

Next, the manner in which the fixing film 13, which is a rotating body, which is a feature of the present invention, is configured to be detachable from the main body of the image heating and fixing device 9 will be described in detail with reference to FIGS. . In the figure, reference numeral 19 denotes a frame of the main body of the image heating / fixing apparatus 9, and reference numeral 13d denotes a crack formed on the fixing film 13 due to durability. When the crack 13d grows, the fixing becomes defective and affects the image. Finally, the fixing film
13 will break itself.

Therefore, the serviceman or the user replaces the fixing film 13 at regular intervals based on the number of recording materials P used before the crack 13d occurs on the fixing film 13. First, press the screw shown in FIGS.
20 is released to release the pressure plate 21 upward, and the pressure spring 22 is removed.

The depressurized coil unit 14 is a support
2, the coil unit 14 and the fixing film 13 can be rotated in the directions indicated by the arrows d in FIG. I have. Then, the fixing film 13 is moved by an arrow e in FIG.
After pulling it out in the direction
Is fitted into the coil unit 14 and inserted in the direction of arrow f in FIG.
Is turned in the direction of arrow c in FIG. 2 to set the coil unit 14 at a position corresponding to the fixing member 24. Then, the pressing screw 20 is tightened to press the pressing plate 21 downward, and the pressing spring 22
The coil unit 14 is lowered by the urging force of
And is stored in the image heating and fixing device 9.

As described above, instead of replacing the fixing film 13 integrally with the coil unit 14, the fixing film 13
With the configuration in which only 13 can be replaced, the exciting coil 15 and the high-permeability core 16 and the like whose life has not been reached can be used as they are, and as a result, the cost of the image heating and fixing device 9 can be suppressed.

In this embodiment, since the toner containing a low softening substance is used, the image heating and fixing device 9 is not provided with an oil application mechanism for preventing offset. In the case where a toner not used is used, an oil application mechanism may be provided. Further, a cooling section may be provided after the fixing nip to perform cooling separation. Also, when a toner containing a low softening substance is used, oil application or cooling separation may be performed.

Further, grease for lubrication is applied on the inner side of the fixing film 13 so that smooth rotation can be performed, but grease remaining on the holding member 14a due to paper passing is reduced. There are cases. In this case, grease may be applied to the inner surface of a new fixing film 13 to be replaced.

Next, a second embodiment of the image heating and fixing apparatus according to the present invention will be described with reference to FIG. FIG. 8 shows the second
FIG. 3 is a diagram illustrating a layer structure of a rotating body of the embodiment. The same components as those in the first embodiment are denoted by the same reference numerals, and description thereof is omitted.

In this embodiment, as shown in FIG. 8, the layer structure of the fixing film 13 is such that an insulating and heat-insulating layer 13 e is provided inside the heat generating layer 13 a to reinforce the fixing film 13.
Examples of the material of the insulating heat insulating layer 13e include a fluororesin, a polyimide resin, a polyamide resin, a polyamideimide resin,
PEEK resin (polyetheretherketone), PES
Resin (polyether sulfone), PPS resin (polyphenylene sulfide), PFA resin (tetrafluoroethylene / perfluoroalkyl vinyl ether copolymer), PTFE resin (polytetrafluoroethylene),
A heat-resistant resin such as an FEP resin (tetrafluoroethylene / hexafluoropropylene copolymer) is preferable.

The thickness of the insulating heat insulating layer 13e is 1
0 to 1000 μm is preferred. If the thickness of the insulating heat insulating layer 13e is smaller than 10 μm, the heat insulating effect cannot be obtained and the durability is insufficient. On the other hand, if it exceeds 1000 μm, the separation distance from the high magnetic permeability core 16 to the heat generation layer 13a increases, and the magnetic flux cannot be sufficiently absorbed by the heat generation layer 13a.

When the insulating heat insulating layer 13e is provided, the heat generating layer 13a
Can be insulated so that the generated Joule heat does not go to the inside of the fixing film 13, so that the efficiency of heat supply to the recording material P is improved as compared with the case where the insulating heat insulating layer 13e is not provided. As a result, power consumption can be reduced.

Next, a third embodiment of the image heating and fixing apparatus according to the present invention will be described with reference to FIG. FIG. 9 shows the third
FIG. 3 is a diagram illustrating a layer structure of a rotating body of the embodiment. The same components as those in the first embodiment are denoted by the same reference numerals, and description thereof is omitted.

In the above embodiments, a four-color image forming apparatus has been described. In the present embodiment, a case where the present invention is applied to a monochrome or one-pass multi-color image forming apparatus will be described.

In this case, as shown in FIG. 9, in the fixing film 13 of the first embodiment, the elastic layer 13b may be omitted and only the heat generating layer 13a and the release layer 13c may be used. With this configuration, the cost of the fixing film 13 is reduced to about half or less. However, since the durability of the fixing film 13 is reduced as compared with the case where the insulating and heat insulating layer 13e and the elastic layer 13b are provided, the frequency of replacing the fixing film 13 is increased. The effect of having the fixing film 13 detachable from the fixing device 9 becomes more remarkable.

Next, a fourth embodiment of the image heat fixing apparatus according to the present invention will be described with reference to FIG. Figure 10 shows the fourth
It is a schematic sectional view showing the structure of an embodiment. In addition, the first
Components configured in the same manner as in the embodiment are given the same reference numerals and description thereof is omitted.

In the present embodiment, an opening for exchanging the fixing film 13 is provided at the upper part of the main body frame 19, and the coil unit 14 is rotated about the rotating shaft 30 through the opening as shown in FIG. After the pressure screw 20 is loosened to remove the pressure plate 21 and the pressure spring 22 in substantially the same manner as in the first embodiment, the rotation shaft 30 And rotated in the direction of arrow g in FIG.
13 is pulled out in the direction of arrow i in FIG. 10 and removed, and a new fixing film 13 is fitted into the coil unit 14 to
Then, the coil unit 14 and the fixing film 13 are rotated in the direction of arrow h in FIG. 10 to set the coil unit 14 at a position corresponding to the fixing member 24. Then, the pressure screw 20 is tightened to press the pressure plate 21 downward, and the coil unit 14 is lowered by the urging force of the pressure spring 22 and is fixed by the fixing member 24 so as to be fixed. 9 is stored.

In the above configuration, since the rotation direction (direction of the arrow h in FIG. 10) when the fixing film 13 is mounted and the pressing direction of the coil unit 14 are performed on the same plane, high mechanical accuracy is ensured. Therefore, there is an advantage that a problem such as axis deviation does not occur.

[0064]

Since the present invention has the above-described configuration and operation, only the rotating body (fixing film) having the shortest service life in the image heating and fixing apparatus can be replaced, so that another apparatus can be provided. Parts that still have a long life can be used as they are, which can greatly reduce the cost of the image heating and fixing device, and also make it possible to use it in a highly efficient manner in terms of saving resources. Was.

[Brief description of the drawings]

FIG. 1 is a schematic cross-sectional explanatory view showing a configuration of a recording unit and a fixing unit of an image forming apparatus provided with an image heat fixing device according to the present invention.

FIG. 2 is a perspective view illustrating a configuration of a first exemplary embodiment of an image heat fixing device according to the present invention.

FIG. 3 is a side view showing the configuration of the first embodiment.

FIG. 4 is an explanatory front view showing the configuration of the first embodiment.

FIG. 5 is an explanatory side sectional view showing the configuration of the first embodiment.

FIG. 6 is a sectional view showing a configuration of an exciting coil.

FIG. 7 is a diagram illustrating a layer structure of a rotating body according to the first embodiment.

FIG. 8 is a diagram illustrating a layer structure of a rotating body according to a second embodiment.

FIG. 9 is a diagram illustrating a layer structure of a rotating body according to a third embodiment.

FIG. 10 is a schematic sectional view illustrating a structure of a fourth embodiment.

FIG. 11 is a diagram illustrating a conventional example.

FIG. 12 is a diagram illustrating a conventional example.

FIG. 13 is a diagram illustrating a conventional example.

[Explanation of symbols]

DESCRIPTION OF SYMBOLS 1 ... Photoreceptor drum, 2 ... Charging roller, 3 ... Laser optical box, 4 ... Laser light, 5 ... Mirror, 6 ... Developing unit, 7 ... Intermediate transfer drum, 8 ... Transfer roller, 9 ... Image heat fixing device, 10, 11 ... cleaner, 12 ... pressure roller, 12a ... core metal,
12b: elastic member, 13: fixing film, 13a: heat generating layer, 13
b: elastic layer, 13c: release layer, 13d: crack, 13e: insulating and heat-insulating layer, 14: coil unit, 14a: holding member, 15: excitation coil, 15a: nickel-plated copper conductor, 15b: ceramic, 15c: polyimide , 16 ... High permeability core, 17, 18 ... Thermistor, 19 ... Frame, 20 ... Pressing screw, 21 ... Pressing plate,
22 ... Pressing spring, 23 ... Post, 24 ... Fixing member, 30 ... Rotating shaft,
N ... nip, P ... recording material, T _1, T ₂ ... toner

Continued on the front page (72) Inventor Hideo Nanataki 3-30-2 Shimomaruko, Ota-ku, Tokyo Inside Canon Inc.

Claims (3)

[Claims] 1. A recording material on which an unfixed toner image is formed is conveyed by a pressing member and a rotating body opposed to the pressing member, and the recording material on the recording material is undetermined across the rotating body. An image heating and fixing apparatus which is located on the opposite side of the toner image and has at least one exciting coil for generating an alternating magnetic field, and a heating section for generating Joule heat by eddy current generated by the exciting coil, An image heating and fixing device, wherein a rotating body is detachable from an image heating and fixing device main body. 2. An image heating and fixing apparatus according to claim 1, wherein said heat generating portion forms a heat generating layer in said rotating body. 3. A conveying unit for conveying a recording material, an image forming unit for forming a toner image on the recording material conveyed by the conveying unit in accordance with image information, and a recording unit formed by the image forming unit. An image forming apparatus, comprising: the image heating and fixing device according to claim 1, wherein the toner image is fixed.