JPH09185984A - Heating device and image forming device - Google Patents

Abstract

PROBLEM TO BE SOLVED: To control a nip width and uniformize heating, thereby preventing the generation of a fixing defect or the like by respectively constituting as a separate body three members of a film guide member provided in the upstream and the downstream of a heating body holding member and a heating nip part. SOLUTION: A recording material P carrying an unfixed toner image is introduced between a rotary fixing film 4 and a pressing roller 5 in the state that an inductive heating plate 2A generates electromagnetic inductive heat with a magnetic field generated by an exciting coil 12 and the temperature of a fixing nip part N is adjusted for a predetermined temperature. The heating fixing of a toner image to the recording material P is performed by conveying the nip part N made to adhere closely to the film 4. At that time, rigidity is made lower than that in the case of one body with the constitution in which a heating holding member 21 and film guide members 22, 23 on the front and the rear sides are constituted as the separate members of three members. Accordingly, when a first stay member 21 is pressed by a second stay member 3, it becomes easy to learn a curved bending in the direction of its length to make it easy to control the distribution of a nip width for a predetermined one.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a heating device and an image forming apparatus.

More specifically, a film heating type heating device, that is, a fixedly held heating element, a film material that slides on the heating element, and a heating nip with the heating element sandwiching the film material. Having a pressure member that forms a portion, and is heated by the heat from the heating element through the film material by introducing the material to be heated between the film material and the pressure member in the heating nip portion and sandwiching and transporting the material. The present invention relates to a heating device that heats a material, and an image forming apparatus that includes the heating device as an image heating device.

[0003]

2. Description of the Related Art For the sake of convenience, a fixing device as an image heating device in an image forming apparatus such as an electrophotographic copying machine, a printer and a fax machine will be described as an example.

The fixing device in the image forming apparatus uses a toner (visual image) made of a heat-meltable resin or the like by an appropriate image forming process means such as electrophotography, electrostatic recording and magnetic recording in an image forming portion of the image forming apparatus. It is an apparatus for heat-treating an unfixed toner image formed on the surface of a recording material by a direct method or an indirect (transfer) method using a material as a permanently fixed image.

Conventionally, a heat roller type device has been widely used as such a fixing device. This is mainly composed of a fixing roller (heat roller) that has a heat source such as a halogen lamp built therein and is heated and adjusted to a predetermined fixing temperature, and a pressure roller and a mutual pressure contact rotary roller pair. The unfixed toner image is recorded by the heat of the fixing roller by introducing the recording material having the unfixed toner image formed thereon as a material to be heated into the nip portion (fixing nip portion, heating nip portion) and nipping and transporting it. It is heated and fixed on the surface.

However, this apparatus has the problems that the heat capacity of the fixing roller is large, the power required for heating is large, and the wait time (wait time from power-on of the apparatus to the state in which print output is possible) is long. .

In this respect, since the film heating type heating device as described above has features such as low power consumption, capable of shortening the wait time, and having a quick start property (on-demand fixing property), it has recently been used. The heating device has come into practical use as a fixing device of an image forming apparatus. What uses a ceramic heater (electric heating member) as a heating element,
Some use an electromagnetic induction heating member.

[0008] FIG. 12 is a schematic cross-sectional view showing a schematic configuration of an example of a film heating type heating device using a ceramic heater as a heating body. FIG. 13 is an enlarged cross-sectional model view of the ceramic heater.

Reference numeral 1 denotes a first stay member, which serves as both a heater holding member and a film guide member, and is a heat-resistant resin molded body having a generally U-shaped cross-section upward.

Reference numeral 2 denotes a ceramic heater as a heating body, which is fixedly held by being attached to the lower surface of the bottom plate portion 1a of the first stay member 1 with a heat resistant adhesive.

Reference numeral 3 denotes a second stay member as a pressing member arranged inside the first stay member 1, which is a metal material molded body having a substantially U-shaped downward cross section.

Reference numeral 4 denotes a cylindrical (endless in the circumferential direction) fixing film, which is loosely fitted on the outside of the first and second stay members 1 and 3.

The first stay member 1, the heater 2, the second stay member 3 and the cylindrical fixing film 4 are all laterally long members having a vertical direction in the drawing. For convenience, the assembly of the above-mentioned members 1 to 4 is referred to as a heating assembly.

Reference numeral 5 denotes a pressure roller (pressure member), which has a solid silicon rubber layer 5b formed concentrically and integrally on the outside of a cored bar 5a and a latex (release layer) coated on the outer surface 5 thereof.
c is an elastic roller.

The pressure roller 5 is arranged so that the shaft portions on both ends of the core metal 5a are rotatably supported between the side plates of an apparatus frame (not shown) through bearings. This pressure roller 5
The above heating assemblies 1 to 4 are arranged with the heater 2 side facing downward, and both end sides of the second stay member 3 are contracted between the member 3 and the stationary member 101a on the apparatus frame side. By pressing the first stay member 1 by pressing it downward with the pressing spring material 7, the lower surface of the heater 2 is pressed against the pressing roller 5 via the fixing film 4 with a predetermined pressing force to press the pressing roller 5. A pressure contact nip portion N (hereinafter referred to as a fixing nip portion) having a predetermined width is formed against the elasticity of the.

The pressure roller 5 is rotationally driven by a driving means M in a counterclockwise direction indicated by an arrow at a predetermined peripheral speed. By the rotational driving of the pressure roller 5, the rotational force acts on the fixing film 4 by the frictional force between the pressure roller 5 and the outer surface of the fixing film 4 in the fixing nip portion N, so that the fixing film 4 moves to the first position.
And, the outer surfaces of the second stay members 1 and 3 rotate in the clockwise direction shown by the arrows while the inner surface thereof slides in close contact with the lower surface of the heater 2 in the fixing nip portion N.

Side wall portions 1b and 1c on the upstream side (front side) and the downstream side (rear side) of the fixing film in the rotational direction of the fixing film, with the bottom plate portion 1a being inside, of the first stay member 1 having a substantially U-shaped cross section.
Guides the inner surface of the fixing film 4 to ensure the stability of rotation of the fixing film 4.

The ceramic heater 2 as a heating element has, for example, a length of 240 as shown in the schematic cross-sectional view of FIG.
Screen printing / firing of a current-generating heating resistance layer 2b in a line or strip along the length of the surface side (film contact sliding surface side) of a horizontally long ceramic substrate 2a such as alumina having a width of 10 mm, a width of 10 mm, and a thickness of 1 mm. And the like, and the surface side on which the energization heating resistance layer is formed is covered with a thin glass protective layer 2c,
A temperature sensor (thermistor) 2d for temperature control and a temperature fuse 8 (FIG. 12) as a safety element are provided on the back surface side of the ceramic substrate 2a, which is a member having a low heat capacity as a whole.

The heater 2 quickly raises the temperature by energizing the energization heating resistance layer 2b. Based on the temperature information detected by the temperature sensor 2d, the temperature control circuit (not shown) controls the energization of the energization heating resistance layer 2b to control the heater temperature appropriately.

The thermal fuse 8 is interposed in series in the energizing circuit for the energizing heat generating resistance layer 2b, is adhered to the back surface of the ceramic substrate 2a with an adhesive 8a, and is also a coil spring disposed inside the first stay member 1. 9 is provided on the back surface of the ceramic substrate 2a by a pressurizing mechanism including the presser 9 and the presser 10. When the heater 2 has an abnormal temperature rise (heater runaway) for some reason, the energization heating resistance layer 2b is formed. It is provided as a safety measure to cut off the power supply to.

Since the fixing film 4 is repeatedly subjected to heat fixing of the toner image, it is excellent in heat resistance, releasability and durability, and is generally 100 μm or less, preferably 50 μm.
Use the following thin, low heat capacity products. For example, a single layer film of a heat-resistant resin such as polyimide, polyether imide, PES, PFA (tetrafluoroethylene-perfluoroalkyl vinyl ether copolymer resin) or a composite layer film, for example, a 20 μm thick film at least on the image contact surface side. 10μm of the release coating layer made by adding conductive material to fluororesin such as PTFE (tetrafluoroethylene resin) and PFA
For example, those applied to m thickness.

In this state, the fixing film 4 is rotated by the rotation of the pressure roller 5, and the heater 2 is heated by the power supply to the heater 2 so that the temperature of the fixing nip portion N rises to a predetermined temperature. The recording material P carrying the unfixed toner image t as a material to be heated is introduced between the rotary fixing film 4 and the pressure roller 5 in the fixing nip portion N, so that the recording material P becomes the fixing film. 4, the fixing nip portion N is nipped and conveyed together with the fixing film 4, and the heat of the heater 2 is received through the fixing film 4 in the course of passing through the fixing nip portion to heat and fix the toner image t. Done. The recording material P passing through the fixing nip portion N is separated from the outer surface of the fixing film 4 at the exit side of the fixing nip portion N and conveyed.

[0023] FIG. 14 is a schematic cross-sectional view showing a schematic configuration of an example of a film heating type heating device using an electromagnetic induction heating member as a heating body. The same components and parts as those of the apparatus shown in FIG. 13 described above are designated by the same reference numerals, and repeated description will be omitted.

Reference numeral 2A denotes a horizontally long induction heating plate (electromagnetic induction heating member; iron sheet metal or the like) as a heating body, which is fixedly held on the lower surface of the first stay member 1.

Reference numeral 11 denotes an exciting coil 12 and a magnetic core (exciting coil core material) 13 arranged inside the first stay member 1.
It is a magnetic field generating means including The induction heating plate 2A as a heating body generates electromagnetic induction heat by an alternating magnetic field (alternating magnetic flux) generated by supplying a high-frequency alternating current (alternating current) to the exciting coil 12 from an exciting circuit (not shown) (induction by the alternating magnetic field). Eddy current is generated in the heating plate 2A, and Joule heat is generated by the eddy current due to the specific resistance of the induction heating plate 2A). The temperature of the induction heating plate 2A is controlled to a predetermined temperature by controlling the high frequency alternating current supplied from the exciting circuit to the exciting coil 12 by a temperature adjusting system including a temperature detecting element (not shown).

Then, the fixing film 4 is rotated by the rotation of the pressure roller 5, and the induction heating plate 2A as a heating body generates heat by electromagnetic induction due to the feeding of the high-frequency alternating current to the exciting coil 12, thereby causing the fixing nip portion. In a state where the temperature of N has risen to a predetermined temperature and is controlled, a recording material P carrying an unfixed toner image t as a material to be heated is provided between the rotary fixing film 4 and the pressure roller 5 in the fixing nip portion N. Is introduced, the recording material P is brought into close contact with the outer surface of the fixing film 4 and is nipped and conveyed along with the fixing film 4 in the fixing nip portion N, and an induction heating plate as a heating body in the course of passing through the fixing nip portion. The toner image t is heated and fixed by receiving the heat of 2 A through the fixing film 4.

[0027]

In the case of a device (FIGS. 12 and 13) using the ceramic heater 2 as a heating element,
A device using the electromagnetic induction heating member 2A as a heating body (see FIG.
Also in the case of 4), it is important that the nip width along the length of the fixing nip portion N is a predetermined width and is substantially uniform in order to prevent fixing defects such as uneven fixing.

However, in the first stay member 1, the heat-resistant resin used is a generally rigid material such as phenol or PPS, and the shape thereof is a holding member for the heating element 2.2A and a film guide. Bottom plate portion 1a that doubles as a member
The first stay member 1 itself has a high rigidity because the first stay member 1 and the side wall portions 1b and 1c on the front and rear sides thereof are a series-integrated member having a substantially U-shaped cross-section upward. Therefore, both ends of the second stay member 3 are pressed by the spring members 7, the second stay member 3 is pressed against the first stay member 1, and the second stay member 1 is pressed to the second stay member 1. The stay member 3 and the pressure roller 5 of FIG. 3 are bent, but since the first stay member 1 has a high rigidity, the first stay member 1 cannot sufficiently follow the second stay member 3 and the pressure roller 5, and the fixing nip It is difficult to control the nip width along the length of the portion N, which causes problems such as improper fixing. Further, the first stay member 1 needs to have sufficient heat resistance for the bottom plate portion 1a for holding the heating bodies 2 and 2A. There is a film guide side wall part 1b.
c is not required to have the same heat resistance as the bottom plate portion 1a.

However, the first stay member 1 of the conventional device is
The bottom plate portion 1a for holding the heating element 2.2A and the film guide side wall portions 1b, 1c on the front and rear sides thereof are integrally integrated with a heat-resistant resin having a heat resistant temperature necessary for the bottom plate portion 1a for holding the heating element 2.2A. This is a member molded into the above, which is one of the causes of cost increase.

The present invention provides a film heating type heating apparatus which solves the above problems and has other effective functions and effects.

[0031]

According to the present invention, there is provided a heating apparatus and an image forming apparatus having the following constitutions.

(1) A heating body fixedly held, a film material that slides on the heating body, and a pressing member that forms a heating nip portion with the heating body with the film material sandwiched therebetween.
A film member having a pressing member for pressing a heating member holding member for fixing and holding a heating member against a pressing member, and introducing a material to be heated between the film member and the pressing member in the heating nip portion to sandwich and convey the film member. In a heating device for heating a material to be heated by the heat from the heating body via, a heating body holding member for fixing and holding the heating body, and a heating nip portion provided on the upstream side and the downstream side in the film moving direction with respect to the moving direction. A heating device, wherein the three members of the first and second film guide members are configured as separate members.

(2) The heating device according to (1), wherein the heating element is a member that generates heat by electromagnetic induction by the magnetic field generated by the magnetic field generating means.

(3) The heating device according to (1), wherein the heating element is an electric heating member that generates heat when energized.

(4) The heating device according to (3), wherein the electric heating member is a ceramic heater.

(5) The heating device according to any one of (1) to (4), wherein the film material is a rotary member which is endless in the circumferential direction.

(6) The heating device according to any one of (1) to (5), wherein the first and second film guide members guide the inner surface of the moving film material.

(7) The pressing member is a rotating body, and the film material is driven to move by the rotation of the pressing member. (1) to (6) Heating device.

(8) The heat resistance of the heating member holding member for fixing and holding the heating member and the heat resistance of the first and second film guide members are
The heating device according to any one of (1) to (7), wherein: heating body holding member ≧ second film guide member ≧ first film guide member.

(9) The first and second film guide members are arranged and held by a pressing member that presses the heating member holding member against the pressing member. The heating device according to any one of claims.

(10) On the mutual contact surface between the heating body holding member and the pressing member that presses the heating body holding member against the pressing member, a plurality of protrusions having arbitrarily different heights in the longitudinal direction are provided. The heating device according to any one of (1) to (9), characterized in that

(11) The heating element is an induction heating plate that generates heat by electromagnetic induction by the magnetic field generated by the magnetic field generating means, the magnetic field generating means has an exciting coil, and windings are wound around the exciting coil core material.
The heating apparatus according to any one of (1), (5) to (10), wherein a closed magnetic circuit is formed by the excitation coil core material and the induction heating plate to heat the induction heating plate.

(12) The heating device according to (11), wherein the pressing member that presses the heating member holding member that holds the heating member against the pressing member is a non-magnetic metal.

(13) The exciting coil is characterized in that it is wound around a winding holding member provided with at least one slit having a diameter width of the winding so that the winding can be wound in a row in a row. The heating device according to (11) or (12).

(14) The heating device according to (13), wherein the exciting coil core material is divided into a plurality of pieces in the longitudinal direction, and the winding holding member holds the divided exciting coil core material. .

(15) A first biasing member is provided to press the exciting coil or winding holding member in the direction of the induction heating plate so as to prevent a gap from being formed between the surfaces contacting the excitation coil core and the induction heating plate. (11) thru | or (14) characterized by the above-mentioned, The heating device as described in any one.

(16) The heating device according to (15), wherein the first biasing member is made of a non-magnetic metal material.

(17) Any one of (11) to (16), characterized in that it has a second urging member for pressing the side surface of the exciting coil or the winding holding member in the longitudinal direction to suppress vibration. The heating device according to.

(18) The heating device according to (17), characterized in that the second biasing member is made of a non-magnetic metal material.

(19) The surface of the induction heating plate is coated with an insulating layer, and the surface of the insulating layer is provided with a temperature detecting means and an electrode conducting member to the temperature detecting means (11). ) Thru | or (18), the heating device as described in any one.

(20) The heating device according to (19), wherein the temperature detecting means is provided on the surface of the induction heating plate on the side of the heating nip portion, and an insulating layer is further provided on the surface of the temperature detecting means.

(21) A temperature fuse is provided by connecting in series to the winding of the exciting coil, and the temperature fuse is wrapped and held by a metal member attached to the winding holding member and having elasticity. (13) to (2)
The heating device according to 0).

(22) The heating according to any one of (13) to (21), characterized in that a thermal fuse is provided by being connected in series to the winding of the exciting coil, and the casing of the thermal fuse is made of a magnetic metal material. apparatus.

(23) Any one of (1) to (22), wherein the material to be heated is a recording material carrying an image.
The heating device according to any one of the above.

(24) In the image forming apparatus having the image forming means for forming an unfixed image on the recording material and the fixing means for thermally fixing the unfixed image formed on the recording material, the fixing means are (1) to (22). An image forming apparatus, comprising: the heating device according to any one of 1).

<Operation> The heating member holding member for fixing and holding the heating member and the three members of the first and second film guide members provided on the upstream side and the downstream side in the film moving direction with respect to the heating nip portion are different from each other. By being configured as a body member ,. The heating member holding member has a lower rigidity than the case where the film guide members are integrally formed. Therefore, in the state where the heating body holding member is pressed by the pressing member, the heating body holding member easily follows the deflection of the pressing member, and the working pressure distribution along the length of the heating body holding member is made uniform to make the heating nip portion It becomes easy to manage the nip width distribution along the longitudinal direction in a predetermined manner.

In this case, a plurality of protrusions having arbitrarily different heights in the longitudinal direction are provided at the mutual contact portion between the heating member holding member and the pressing member, and these protrusions are heated from the pressing member as force acting points. By applying a pressing force to the body holding member, it is possible to correct the non-uniformity of the acting force distribution along the length of the heating body holding member in accordance with the longitudinal deflection of the pressing member and the pressure deflection of the pressing member. By appropriately bending the heating member holding member in this manner, the nip width distribution along the length of the heating nip portion can be made uniform in a predetermined and more reliable manner.

[0058] It is possible to differ the heat resistance performance of the heating body holding member and the first and second film guide members,
By defining the relationship of the heating member holding member ≧ second film guide member ≧ first film guide member,
For the first and second film guide members, an inexpensive material having lower heat resistance than the heating body holding member can be used, and like the conventional heating body holding member and the film guide member, It is not necessary to match all the required heat resistance of the heating member holding member portion, and the cost can be reduced.

[0059] By mounting and arranging the first and second film guide members on the outer surfaces of the side wall portions on the upstream side and the downstream side of the pressing member of the heating member holding member in the film material moving direction, the inside of the pressing member of the heating member holding member is disposed. The space can be effectively used by expanding the space, and space saving and downsizing can be achieved.

In the case where the heating device is of a system in which an induction heating plate is used as the heating body and the induction heating plate is caused to generate heat by the magnetic field generating means, the exciting coil of the magnetic field generating means is
By winding the winding around a winding holding member having slits having the diameter width of the winding (conductor wire) so that the windings can be wound in a row, the winding is guided, and the winding is guided between the upper and lower and adjacent windings. Withstand voltage characteristics are maintained.

The core of the exciting coil is divided into a plurality of pieces in the longitudinal direction, so that even if the heating member holding member or the induction heating plate as the heating member or the pressing member is bent by the pressing force of the pressing member, The core material of the magnetic field generation means easily follows the back surface of the heating plate in the longitudinal direction of the induction heating plate, a gap is less likely to form between the core material and the induction heating plate, and the reduction in heat generation efficiency of the induction heating plate is prevented.

The temperature detecting means is provided on the sliding surface side (front surface side) of the induction heating plate as a heating body while being protected by an insulating layer so that the temperature detecting means is provided on the back surface side of the induction heating plate. The temperature condition of the heating nip portion can be more accurately performed than in the case of the above.

The temperature fuse is held by an induction heating member, or the casing of the temperature fuse is used as an induction heating member, so that when the heating body is out of control, these induction heating members also become overheated to the exciting coil. Since the energization of the thermal fuse is cut off, the disposition form and means of the thermal fuse can be simplified.

The first and second biasing members are interposed between the magnetic field generating means and the pressing member for pressing the heating body holding member to bring the magnetic field generating means into the pressed state, so that the exciting coil of the magnetic field generating means is excited. Vibration of the magnetic field generating means generated by the high-frequency alternating current flowing is suppressed, and the heat of the magnetic field generating means is radiated to the pressing member to be dissipated to prevent the exciting coil itself from generating heat and lowering the efficiency.

[0065]

BEST MODE FOR CARRYING OUT THE INVENTION

<Embodiment 1> (FIGS. 1 to 7) (1) Example of image forming apparatus FIG. 1 is a schematic view of an example of an image forming apparatus. The image forming apparatus of this embodiment is a copying machine or a printer using a transfer type electrophotographic process.

Reference numeral 51 is a rotary drum type electrophotographic photosensitive member (hereinafter referred to as photosensitive drum) as an image bearing member. It is rotationally driven at a predetermined peripheral speed (process speed) in the clockwise direction indicated by the arrow.

Numeral 52 is a charging roller as a primary charging means for uniformly charging the outer peripheral surface of the rotating photosensitive drum to a predetermined polarity and potential.

Image exposure 53 (corresponding to original image slit exposure, laser beam scanning exposure, etc.) corresponding to the desired image information is provided on the surface of the rotary photosensitive drum 51 which is subjected to the primary charging process. By being done,
An electrostatic latent image corresponding to the exposure image is formed on the rotating photosensitive drum surface.

Reference numeral 54 is a developing means. The electrostatic latent image formed on the rotating photosensitive drum surface is developed as a toner image.

Reference numeral 55 is a transfer roller. The toner image on the surface of the rotating photoconductor drum is transferred onto a transfer material P as a recording material that is fed from a paper feeding unit (not shown) at a transfer unit between the rotating photoconductor drum 51 and the transfer roller 55.

Reference numeral 56 is a cleaning means. Transfer material P
After the transfer of the toner image, the surface of the rotating photosensitive drum is cleaned.

The transfer material P that has received the toner image transfer from the surface of the rotating photosensitive drum at the transfer portion is the rotating photosensitive drum 51.
The image is separated from the surface, is conveyed through the guide member 57 and is introduced to the image heating and fixing device 58 as a heating device, undergoes heat fixing processing of the toner image, and is output as a copy or a print.

(2) Image Heat Fixing Device 58 FIG. 2 is a cross-sectional model view of the fixing device of this embodiment, FIG. 3 is a vertical cross-sectional model view, and FIG. 4 is a schematic exploded perspective view of the heating assembly.

The apparatus of this example is a film heating type apparatus using an electromagnetic induction heating member (induction heating plate) as a heating body, and the same reference numerals are used for the components and parts common to those of the apparatus shown in FIG. Will be added and the description thereof will be omitted.

A) Overall configuration of apparatus 100 is an apparatus frame having a bottom plate and left and right side plates, 10
1 is placed on the upper side of the device frame, and the device frame 10
It is a cover plate screwed to 0.

The pressure roller 5 (pressure member) is rotatably supported at its both end shaft portions 5d and 5d through bearings 5f and 5f between the left and right side plates of the apparatus frame as shown in FIG.
The pressure roller 5 includes a cored bar 5a, an elastic layer 5b on the outer side of the cored bar 5a made of silicon rubber or fluororubber, and a release layer 5 on the surface of the elastic layer.
c, a conductive rubber disk 5e or the like provided on one end surface side of the roller.

In the heating assembly, with the induction heating plate 2A as a heating member facing downward, the outward protruding portions on both ends are fitted into the vertical guide slots formed on the left and right side plates of the apparatus frame 100 from above. Are engaged with each other, dropped between the left and right side plates, and placed on the pressure roller 5. The upper side of the device frame 100 is covered with a cover plate 101 and screwed integrally to the device frame.

Overhangs 3 on both ends of the second stay member 3 in the outward overhangs on both ends of the heating assembly.
The spring receiving pieces 14 and 14 are attached to the a and 3a, and the pressing spring members 7 are provided between the spring receiving pieces 14 and 14 and the projecting portions 101a and 101a on both ends of the cover plate 101, respectively.・ 7 is reduced.

As a result, the second stay member 3 is pressed downward by the pressure spring members 7 on both ends thereof to press the first stay member 21, and the first stay member 2 is pressed.
The lower surface of the induction heating plate 2A serving as a heating body fixedly held at 1 is pressed against the pressure roller 5 through the fixing film 4 with a predetermined pressing force to fix the pressure roller 5 against the elasticity of a predetermined width. A nip portion N is formed.

The heating assembly is disposed on the first stay member 21 having a horizontally long frame shape, the induction heating plate 2A fixedly held in the frame of the first stay member 21, and the induction heating plate 2A. Excitation coil 12 and magnetic core (excitation coil core material) 13
And the like, a second stay member 3 having a substantially U-shaped cross-section downwardly facing and arranged on the first stay member 21 so as to cover the magnetic field generator 11, and the second stay member 3. First mounted on the outer surface of the front and rear side walls
And the second film guide members 22 and 23, the cylindrical fixing film 4 loosely fitted around the outer periphery of the above assembly, and the film deviation movement restricting flange members fitted to both ends of the second stay member 3. 24 ・ 24, etc.

The apparatus of this embodiment is also shown in FIGS.
2, the pressure roller 5 is rotationally driven in the counterclockwise direction indicated by the arrow in FIG. 2 at a predetermined peripheral speed by a driving unit (not shown). By the rotational drive of the pressure roller 5, the fixing film 4 slides around the outer circumferences of the first and second stay members 21 and 3, and the inner surface thereof closely contacts the lower surface of the induction heating plate 2A as a heating body in the fixing nip portion N. While moving, rotate clockwise as shown by the arrow.

The first and second film guide members 22 and 23 mounted and arranged on the outer surfaces of the side wall portions on the front and rear sides of the second stay member 3 are located on the upstream and downstream sides of the fixing nip portion N in the film rotation direction. It guides the inner surface of the fixing film 4 and serves to ensure the stability of rotation of the fixing film 4.

The flange members 24, 24 are the fixing film 4
The movement of the film 4 along the longitudinal direction of the first and second stay members 21 and 3 that occurs during the rotation process is regulated.

The fixing film 4 is rotated by rotationally driving the pressure roller 5, and induction heating as a heating body is performed by a magnetic field generated by the exciting coil 12 by feeding a high frequency alternating current from an exciting circuit (not shown) to the exciting coil 12. In the state where the plate 2A heats up by electromagnetic induction and the temperature of the fixing nip portion N rises to a predetermined temperature and is temperature-controlled, as a material to be heated between the rotary fixing film 4 and the pressure roller 5 of the fixing nip portion N, The recording material P carrying the unfixed toner image is guided and introduced by the entrance guide plate 25, so that the recording material P comes into close contact with the outer surface of the fixing film 4 and the fixing nip portion N together with the fixing film 4. The toner image is nipped and conveyed, and in the course of passing through the fixing nip portion, the heat of the induction heating plate 2A as a heating body is received via the fixing film 4 to heat and fix the toner image.
The recording material P that has passed through the fixing nip portion N is separated from the outer surface of the fixing film 4 at the outlet side of the fixing nip portion N, and is discharged and conveyed through the path of the outlet guide plate 26 and the fixing paper discharge roller pair 27.

The second stay member 3 is a molded body of a non-magnetic metal material (such as non-magnetic SUS) having no electromagnetic induction heat generation property,
While functioning as a pressing member for the first stay member 1,
It also serves to improve heat conduction in the fixing nip portion N in the longitudinal direction and reduce uneven temperature distribution in the fixing nip portion N in the longitudinal direction.

The fixing film 4 is a film having a small heat capacity and is 100 μm in order to enable quick start.
a polyimide having a heat resistance and high elasticity with a thickness of m or less,
For example, a base layer in which a high thermal conductive member such as carbon or a metal filler is mixed with polyimide amide or the like is coated with a fluororesin layer such as PFA or PTFE.

The conductive rubber disk 5e provided on one end surface side of the pressure roller 5 is in contact with the conductive layer surface exposed at the end portion of the fixing film 4 on that side, and applies a charging charge generated on the fixing film 4. The pressure roller 5 plays a role of leaking through the core metal 5a and the like.

B) Temperature control The induction heating plate 2A as a heating body has a thickness of 0.1 to 2 mm.
Made of a horizontally elongated metal plate material such as iron / ferromagnetic SUS, etc., and a low heat capacity conductive chip thermistor 28 (FIG. 2) is attached to the back side (side opposite to the film contact sliding side). In accordance with the output of the chip thermistor 28, a switching power supply (frequency variable power supply) of an exciting circuit (not shown) applies a high-frequency alternating current to the exciting coil 12 so that the exciting coil 12 generates an alternating magnetic field. At this time, the induction heating plate 2
An eddy current flows inside A so as to prevent the above-mentioned change in the generated magnetic field. This eddy current generates Joule heat according to the resistance of the induction heating plate 2A, and the induction heating plate 2A generates heat.
The temperature information of the induction heating plate 2A due to this heat generation is sent to the CPU by the chip thermistor 28, and based on this, C
The PU sets the oscillator of the AC power source to the optimum frequency and controls the exciting coil 12 to apply the AC current of the optimum frequency to control the temperature of the induction heating plate 2A to a predetermined value.

C) First stay member 21, first and second film guide members 22 and 23 First stay member 1 in the apparatus shown in FIGS. 12 and 14 described above.
Is a bottom plate portion 1a and front and rear side wall portions 1 thereof which also serve as a holding member for the heating elements 2 and 2A and a film guide member.
b. 1c is a member of a substantially U-shaped cross-sectional upward cross-section that is integrally formed. In the present invention, a heating member holding member and
The film guide members on the front and rear sides are 3 members individually.
It is set as 1.22.23.

That is, the first stay member 21 functions as a heating member holding member, and the first and second film guide members 22 and 23 are upstream and downstream of the film rotating direction.
The second stay member 3 which presses the first stay member 21 as a separate member from the first stay member 21.
It was attached to the outer surface of the front and rear side wall parts.

The first stay member 21 serving as a heating member holding member has an induction heating plate 2A serving as a heating member having both longitudinal ends thereof provided at both longitudinal ends of the stay member 21.
a. 21a (FIG. 3 and FIG. 5 (b)). The first stay member 21 is made of a heat-resistant resin having a heat-resistant temperature required as a heating body holding member. In a high-speed electrophotographic apparatus, the induction heating plate 2A as a heating element rises to about 200 to 240 ° C., so a material having high heat resistance is required. In this example, a liquid crystal polymer is used for the first stay member 21.

First and second film guide members 22.2
No. 3 is not required to have the heat resistance as high as that of the first stay member 21 as the heating body holding member, so that a material having relatively low heat resistance is sufficient. In this example, PPS is used for the first and second film guide members 22 and 23.

That is, the heat resistance of the first stay member 21, the first and second film guide members 22 and 23 are
The stay member 21 ≧ second film guide member 23 (downstream side) ≧ first film guide member 23 (upstream side) can be configured.

As described above, the heating member holding member 21 and the film guide members 22 and 23 on the front and rear sides (upstream and downstream sides) thereof.
Is made up of three individual members. The first stay member 21 as the heating body holding member,
The rigidity is reduced as compared with the case where the film guide members 22 and 23 are integrally formed.

For that purpose, both ends of the second stay member 3 are pressed by the spring members 7 and 7 to press the second stay member 3 against the first stay member 21 and press the first stay member 21. In this state, the first stay member 21 can easily follow the curved bending of the second stay member 3 which is convex upward in the longitudinal direction,
The acting pressure distribution along the length of the first stay member 21 is made uniform, and the nip width distribution along the length of the fixing nip portion N can be easily managed in a predetermined manner.

In this case, as shown in the model view of FIG. 5A and the plan view of the first stay member 21 in FIG. 5B, the first stay member 21 as a heating body holding member and its pressing member. A plurality of protrusions 21b, 21c, 21d having different heights in the longitudinal direction at the mutual contact portion with the second stay member 3.
By providing a pressing force from the second stay member 3 to the first stay member 21 by using these protrusions as force acting points, the second stay member 3 and the pressure roller 5 are pressed. In order to compensate for the deflection, the first stay member 21 is corrected so as to correct the non-uniformity of the acting pressure distribution along the length of the first stay member 21.
The stay member 21 of No. 3 is appropriately bent to fix the fixing nip portion N.
It is possible to make the nip width distribution along the longitudinal direction of the sheet uniform and more reliable.

In FIG. 5A, a first protrusion 21b having a height of 0.15 mm is provided on the side of the first stay member 21 at a substantially central portion in the longitudinal direction of the contact portion with the second stay member 3. , 2 mm with a height of 0.1 mm on each side
And the third protrusions 21c and 21d are provided, and the protrusions 21b, 21c, and 21d having different heights are used as force acting points from the second stay member 3 to the first stay member 2.
By applying a pressing force to 1, the nip width distribution along the length of the fixing nip portion N is made uniform in a predetermined and more reliable manner.

The protrusions 21b, 21c, and 21d may be provided on the second stay member 3 side, or may be provided on both the first and second stay members 21.3.

[0099] First stay member 21, first and second
The heat resistance performance of the film guide members 22 and 23 of the first stay member 21 ≧ second film guide member 23 ≧ first
The first and second film guide members 22 and 23 are defined by the related configuration of the film guide member 23 of FIG.
For the above, a heat resistant material which is lower in heat resistance than the first stay member 21 can be used, and a heating body holding member portion is required like a member that doubles as a conventional heating body holding member and a film guide member. It is not necessary to match everything with heat resistance, and cost can be reduced.

[0100] First and second film guide member 2
By mounting 2 and 23 on the outer surfaces of the side wall portions of the second stay member 3 on the upstream side and the downstream side in the film rotation direction, the space inside the second stay member 3 can be widened and used effectively. It is possible to save space and reduce the size.

D) Magnetic field generating means 11 FIG. 6 is an exploded perspective view of the winding holder 12a (winding holding member) and the magnetic core 13 of the magnetic field generating means 11.

The winding holder 12a includes vertically-extending laterally long magnetic core sandwiching plate portions 12b and 12c, a connecting portion 12d on one longitudinal end side of both sandwiching plate portions, and an opening opening 12e on the other end side. The heat-resistant resin molded body has a plurality of parallel fins 12f provided along the length on the outer surfaces of the upper and lower sandwich plate portions 12b and 12c. The interval (slit) between the parallel fins 12f corresponds to the diameter width of the conductive wire of the exciting coil 12, and the conductive wire of the exciting coil 12 can be wound in a vertical line.

The magnetic core 13 as the exciting coil core is made of a ferromagnetic material such as ferrite. In this example, a closed magnetic path is formed by the magnetic core 13 and the induction heating plate 2A as the heating body as shown in FIG. In order to heat the induction heating plate by a U-shaped member having a downward cross-section, a plurality of required lengths, in this example, four short magnetic cores 13 (a) -1.
3 (d) is put together and configured.

The four short magnetic cores 13 (a) to 13
The flat plate portion of (d) is sequentially inserted from the opening 12e of the winding holder 12a into the gap 12g between the upper and lower sandwiching plate portions 12b and 12c, and the four short magnetic cores 13 are provided for convenience.
(A) to 13 (d) are assembled and held in the winding holder 12a as shown by the chain double-dashed line in FIG. Next, the exciting coil 12 is formed by winding the conductor wires in a vertical line between the fins of the plurality of parallel fins 12f outside the winding holder 12a. The parallel fins 12f of the winding holder 12a guide the conductive wires of the exciting coil 12 and maintain the withstand voltage characteristics between the upper and lower adjacent conductive wires.

The magnetic field generating means 11 is the winding holder 12
The upper surface side of a is constantly pressed and urged downward by the pressure springs 30 and 30 (FIG. 2 and FIG. 3, first urging member) of the non-magnetic metal material provided on the inner upper surface of the second stay member 3. The magnetic core 13 is pressed against the back surface of the induction heating plate 2A as a heating body. The pressing springs 30 and 30 are made of a non-magnetic SUS material or the like so that induction heating does not occur even when a high frequency alternating current flows through the exciting coil 12.

In this example, since the magnetic core 13 is divided into four in the longitudinal direction as described above, the first stay member 21 as a heating member holding member, the induction heating plate 2A as a heating member, the pressure roller. Even if 5 is deflected by the pressing force of the second stay member 3, the magnetic cores 13 (a) to 13 (d) of the magnetic field generating means 11 follow the back surface of the induction heating plate 2A in the longitudinal direction of the induction heating plate 2A. Easy, induction heating plate 2A
A gap is unlikely to be formed between the induction heating plate 2A and the induction heating plate 2A, and the reduction in heat generation efficiency of the induction heating plate 2A is prevented.

In FIGS. 2 and 3, 8 is an exciting coil 12
It is a thermal fuse connected by intervening in series with the winding conducting wire of. This thermal fuse 8 is attached to the winding holder 12a in contact with the thermal fuse sheet metal 29. The thermal fuse sheet metal 29 is made of an electromagnetic induction heat-generating member, and is configured to be wound in a cylindrical shape so as to have a spring property, so that the thermal fuse 8 is held and brought into close contact. The induction heating plate 2A as a heating body is induction-heated by the magnetic field generated by applying the high-frequency alternating current to the excitation coil 12, and the temperature fuse sheet metal 29 is also electromagnetically induction-heated to raise the temperature.
The temperature control cannot be controlled for some reason and the temperature fuse sheet metal 29
When the temperature rises above a predetermined temperature, the temperature fuse 8 in contact therewith is actuated to interrupt the energization of the winding wire of the exciting coil 12 and stop the current flow.

<Embodiment 2> (FIGS. 8 and 9) In Embodiment 2, the induction heating plate 2A as a heating element is devised in the apparatus of Embodiment 1 described above. The rest of the device configuration is the same as that of the device of the first embodiment, and therefore the repetitive description will be omitted.

That is, the induction heating plate 2A of this example is made of iron / iron, as shown in the layer structure model diagram of FIG. 8 and the partially cutaway perspective view of FIG.
A first heat-resistant insulating layer 2 ₂ is formed on the surface side of an electromagnetic induction heat-generating metal substrate 2 ₁ such as a ferromagnetic SUS, and a chip as a temperature detecting means is formed on the first heat-resistant insulating layer 2 _2. A thermistor 28 is provided. A circuit conducting portion (electrode conducting member) 2 ₃ to the chip thermistor 28 is formed and provided on the first heat resistant insulating layer 2 ₂ by a printing method or the like. The surface of the first heat resistant insulating layer 2 ₂ including the chip thermistor 28 and the circuit conducting portion 2 ₃ is connected to the end electrode portion 2 ₄ of the circuit conducting portion 2 _3.
Is exposed and covered with the second heat resistant insulating layer ₂₅ , and the induction heating plate 2A itself is a metal substrate.

This induction heating plate 2A is a chip thermistor 2
The surface provided with 8 is used as the film contact sliding surface side. Since the chip thermistor 28 is present on the film contact sliding surface side, the chip thermistor 28 is moved to the induction heating plate 2A.
The temperature condition of the fixing nip portion N can be made more accurate than in the case where it is provided on the back surface side. Induction heating plate 2
Together with the second heat-resistant insulating layer 2 ₅ which is the surface layer of A to protect the chip thermistor 28 and the circuit conducting portion 2 _3, and functions as a sliding sliding surfaces of the film 4, it serves to suppress the wear of the film Is playing.

<Embodiment 3> (FIG. 10) In Embodiment 3, the temperature fuse 8 of the apparatus of Embodiment 1 is modified. The rest of the device configuration is the same as that of the device of the first embodiment, and therefore the repetitive description will be omitted.

FIG. 10 is a partially cutaway front view of the thermal fuse 8. In this example, the casing 8a of the thermal fuse 8 is shown.
Is made of ferromagnetic SUS or the like, and the induction heating plate 2A as a heating body is induction-heated by a magnetic field generated by applying a high-frequency alternating current to the exciting coil 12, and the casing 8a of the thermal fuse 8 itself. Is also heated by induction heat generation. If the temperature control cannot be performed for some reason and the casing 8a of the temperature fuse 8 is abnormally heated to a predetermined temperature or higher, the temperature fuse 8 is actuated to interrupt the energization of the winding wire of the exciting coil 12 and prevent current from flowing. It has become.

In the case of this example, the thermal fuse sheet metal 29 for holding the thermal fuse 8 may be made of a non-magnetic metal material.

<Fourth Embodiment> (FIG. 11) In the fourth embodiment, the magnetic field generating means 11 in the heating assembly is constantly pressed in the lateral direction (sheet passing direction, horizontal direction) in the apparatus of the first embodiment. It is provided with a biasing member (second biasing member) for biasing. The rest of the device configuration is the same as that of the device of the first embodiment, and therefore the repetitive description will be omitted.

That is, in the present example, as shown in FIG. 11, the magnetic core 12 of the magnetic field generating means 11 and the winding holder 12a are connected to the right side surface in the drawing and the inner surface of the side wall portion of the second stay member 3 on that side. A biasing member (spring plate member) 31 is contracted between the
The magnetic field generating means 11 is constantly pressed and biased to the left so that the left side surface of the magnetic core 12 of the magnetic field generating means 11 is moved to the first stay member 2.
The inner side surface of the frame piece on that side of 1 is received and held in a pressed state.

The biasing member 31 is made of a non-magnetic SUS material so that induction heat is not generated even when a high frequency alternating current flows through the exciting coil 12. The biasing member 31 is a first biasing member for pressing the vibration of the magnetic field generating means 11 generated by the high-frequency alternating current flowing through the exciting coil 12 against the induction heating plate 2A by pressing the magnetic field generating means from above. Thirty
In addition to suppressing the heat, the heat of the magnetic field generating means 11 is released to the second stay member 3 made of metal to radiate the heat, thereby preventing the exciting coil 12 itself from generating heat and lowering the efficiency.

Contrary to the above, the biasing member 3 is provided between the magnetic core 12 of the magnetic field generating means 11 and the winding holder 12a on the left side in the drawing and the inner surface of the side wall portion of the second stay member 3 on that side.
1 is contracted and the magnetic field generating means 11 is always pressed and urged rightward so that the right side surface of the magnetic core 12 of the magnetic field generating means 11 is set to the first side.
It is also possible to have a structure in which the stay member 21 is received by the inner surface of the frame piece on the side of the stay member 21 and is brought into a holding state.

<Others> a) Although the apparatus of the embodiment is an electromagnetic induction heating type apparatus, the present invention can also be applied to an apparatus using a ceramic heater as a heating body.

B) Like the image heating and fixing devices of Embodiments 1 to 4, the pressure roller 5 having the fixing nip portion N formed by loosely fitting the cylindrical fixing film 4 on the film guide member is used. The device configuration in which the fixing film 4 is rotated by rotationally driving (pressure roller driving system) is such that no tension is applied to the film portion other than the fixing nip portion and the vicinity thereof during the rotation of the fixing film (tensionless). Sometimes, the displacement force of the film along the length of the film guide member is small. Therefore, there is an advantage that the means for restricting the deviation of the film may be a simple means structure such as simple flange members 24, 24 for receiving the end portions of the film.

C) The fixing film 4 may have a device structure in which an endless belt-shaped member is stretched between two or more members and is rotationally driven by a pressure roller or a driving means other than the pressure roller. The device configuration may be such that an endless long fixing film wound with rollers is moved.

D) The heating device of the present invention is not limited to the image heating and fixing device of the embodiment, but the image recording such as gloss is modified by heating the recording material carrying the image to modify the surface property such as gloss, and image heating such as hypothetical wearing. It can be widely used as a device and other means for heating and heating a material to be heated such as a heating and drying apparatus for a material to be heated and a heating laminating apparatus.

E) In comparison with a device using a ceramic heater as a heating element and an electromagnetic induction heating type device using an electromagnetic induction heating member as a heating element, the electromagnetic induction heating type device has the following advantages. There is.

That is, in the case of an apparatus using a ceramic heater as the heating element, the thickness of the glass protective layer 2c in the ceramic heater 2 (FIG. 13) as the heating element improves the heat transfer to the fixing nip portion N, It is preferable that the heater is thin in order to shorten the wait time, but the ceramic heater 2 to which AC power is applied
Between the fixing film 4 and the fixing film 4, it is necessary to satisfy sufficient withstand voltage characteristics, and it is difficult to make the film extremely thin. Therefore, it becomes difficult to raise the temperature of the sheet material of the unfixed toner image to a predetermined temperature before it reaches the fixing device, and it is difficult to cope with a high-speed electrophotographic device.

When fixing a small size recording material, in the non-sheet passing area in the fixing nip portion N, the temperature of the heater rises because heat is not transferred to the recording material, and in the worst case, the ceramic heater 2 or The stay member 1 and the like may be thermally damaged.

Heat generating resistance layer portion 2 of ceramic heater 2
b is accommodated in the fixing nip portion N. This is because if there is a protruding portion outside the nip portion N,
The heat radiated from the portion protruding outside the nip portion N to the pressure roller 5 and the like is smaller than the heat radiation in the portion accommodated in the nip portion, and is abnormally heated. In the worst case, the ceramic heater 2 Leading to breakage. Since a high-speed machine generally requires a large amount of heat for fixing, the width of the heating resistance layer portion inevitably becomes wide, and in order to avoid the breakage of the ceramic heater 2, the pressure roller 5 is used. It is also necessary to make the nip width of the wide. However, widening the nip width of the pressure roller 5 leads to an increase in driving torque.
This will cause an increase in the cost of the motor, etc.

The temperature sensor 2c in the ceramic heater 2 is provided on the surface opposite to the heating resistance layer 2b. Also,
As described above, it is difficult to make the thickness of the glass protective layer 2c extremely thin, and a certain thickness is required. Therefore, the temperature detected by the temperature sensor 2c cannot be accurately grasped as the actual temperature of the nip portion,
The temperature of the nip portion is lower than the detected temperature, which causes problems such as improper fixing.

In the conventional example, the thermal fuse 8 (FIG. 12)
Is applied to the ceramic heater 2 serving as a heating body and is adhered with a conductive adhesive, the temperature fuse pressing member 9
・ The number of parts such as 10 was large, and it took a lot of assembly man-hours, which was a factor of cost increase.

In the case of an electromagnetic induction heating type device using an electromagnetic induction heating member as a heating body, the above problems can be avoided.

[0129]

As described above, according to the present invention, in a film heating type heating device using a ceramic heater (electric heating member) or an induction heating plate as a heating body, the nip width along the length of the heating nip portion is desired. Further, it is easy to control and manage, and the heating of the material to be heated can be made uniform, so that it is possible to prevent the occurrence of fixing defects such as uneven fixing in the image heating and fixing device. In addition, effective functions and effects can be provided as described above.

[Brief description of the drawings]

FIG. 1 is a schematic view of an example of an image forming apparatus.

FIG. 2 is a schematic cross-sectional view of the fixing device.

FIG. 3 is a schematic vertical sectional view of the fixing device.

FIG. 4 is a schematic exploded perspective view of a heating assembly.

5A is a vertical cross-sectional schematic view of a fixing device showing a part different from FIG. 3, and FIG. 5B is a plan view of a first stay.

FIG. 6 is an exploded perspective view of a winding holder and a magnetic core.

FIG. 7 is a schematic cross-sectional view of the magnetic field generating means.

FIG. 8 is a layer configuration model diagram of an induction heating plate according to the second embodiment.

FIG. 9 is a partially cutaway perspective view of an induction heating plate.

FIG. 10 is a partially cutaway front view of a thermal fuse according to a third embodiment.

FIG. 11 is a schematic cross-sectional view of the heating assembly according to the fourth embodiment.

FIG. 12 is a schematic cross-sectional view showing a schematic configuration of an example of a film heating type heating device (fixing device) using a ceramic heater as a heating body.

FIG. 13 is an enlarged cross-sectional model view of a ceramic heater.

FIG. 14 is a schematic cross-sectional view showing a schematic configuration of an example of a film heating type heating device (fixing device) using an electromagnetic induction heating member as a heating body.

[Explanation of symbols]

 21 1st stay member (heating body holding member) 22 and 23 1st and 2nd film guide member 11 Magnetic field generation means 12 Excitation coil 13 Magnetic core 3 2nd stay member (pressing member) 4 Fixing film 5 Pressurization Roller N Fixing nip (heating nip) P Recording material (heated material) 29 Thermal fuse

Claims (24)

[Claims] 1. A heating body fixedly held, a film material slidingly moving on the heating body, a pressure member forming a heating nip portion with the heating body with the film material sandwiched therebetween, and a heating body. A heating member holding member for fixing and holding the heating member holding member to a pressing member, and a heating target material is introduced between the film material and the pressing member in the heating nip portion to be sandwiched and conveyed to interpose the film material. In the heating device for heating the material to be heated by the heat from the heating body, a heating body holding member for fixing and holding the heating body, and a first provided on the upstream side and the downstream side in the film moving direction with respect to the heating nip portion. A heating device, wherein the three members of the second film guide member are configured as separate members from each other. 2. The heating element is a member that generates heat by electromagnetic induction by the magnetic field generated by the magnetic field generating means.
A heating device according to claim 1. 3. The heating device according to claim 1, wherein the heating element is an electric heating member that generates heat when energized. 4. The heating device according to claim 3, wherein the electric heating member is a ceramic heater. 5. The film member is a rotating member which is endless in the circumferential direction, and the film member is a rotating member.
The heating device according to any one of the above. 6. The heating device according to claim 1, wherein the first and second film guide members guide the inner surface of the moving film material. 7. The heating device according to claim 1, wherein the pressing member is a rotating body, and the film member is driven to move by rotation of the pressing member. 8. A heating body holding member for fixing and holding a heating body, and heat resistance performances of the first and second film guide members are as follows: heating body holding member ≧ second film guide member ≧ first film guide member, The heating device according to any one of claims 1 to 7, wherein: 9. The first and second film guide members are arranged and held by a pressing member that presses the heating member holding member against the pressing member.
The heating device according to any one of the above. 10. A plurality of protrusions having arbitrarily different heights in the longitudinal direction are provided on the mutual contact surfaces of the heating body holding member and the pressing member that presses the heating body holding member against the pressing member. The heating device according to any one of claims 1 to 9, characterized in that. 11. The heating body is an induction heating plate that generates heat by electromagnetic induction by a magnetic field generated by the magnetic field generating means, the magnetic field generating means has an exciting coil, and a winding is wound around the exciting coil core material, and the exciting coil core material is provided. 11. The heating device according to claim 1, wherein a closed magnetic path is formed by the induction heating plate to heat the induction heating plate. 12. The heating device according to claim 11, wherein the pressing member that presses the heating member holding member that holds the heating member against the pressing member is a non-magnetic metal. 13. The exciting coil has at least one slit having a diameter width of the winding so that the winding can be wound in a vertical row.
The heating device according to claim 11 or 12, wherein the heating device is wound around an individual winding holding member. 14. The heating device according to claim 13, wherein the exciting coil core material is divided into a plurality of pieces in the longitudinal direction, and the winding holding member holds the divided exciting coil core material. 15. A first urging member for pressing the exciting coil or the winding holding member in the direction of the induction heating plate so as to prevent a gap from being generated between the surfaces contacting the excitation coil core and the induction heating plate. The heating device according to any one of claims 11 to 14, characterized in that. 16. The heating device according to claim 15, wherein the first biasing member is made of a non-magnetic metal material. 17. The second urging member for pressing the side surface of the exciting coil or the winding holding member in the longitudinal direction to suppress the vibration, as set forth in any one of claims 11 to 16. Heating device. 18. The heating device according to claim 17, wherein the second biasing member is made of a non-magnetic metal material. 19. The method according to claim 11, wherein the surface of the induction heating plate is coated with an insulating layer, and the surface of the insulating layer is provided with a temperature detecting means and an electrode conducting member to the temperature detecting means. 19. The heating device according to any one of 18 to 18. 20. The heating device according to claim 19, wherein the temperature detecting means is provided on the surface of the induction heating plate on the heating nip side, and an insulating layer is provided on the surface of the temperature detecting means. 21. A temperature fuse is provided by being connected in series to a winding of an exciting coil, and the temperature fuse is wrapped and held by a metal member attached to the winding holding member and having elasticity. The heating device according to claim 13, wherein the heating device is a heating device. 22. The heating device according to claim 13, wherein a thermal fuse is provided by being connected in series to the winding of the exciting coil, and the casing of the thermal fuse is made of a magnetic metal material. 23. The heating device according to claim 1, wherein the material to be heated is a recording material carrying an image. 24. An image forming apparatus having an image forming means for forming an unfixed image on a recording material and a fixing means for thermally fixing the unfixed image formed on the recording material, wherein the fixing means is any one of claims 1 to 22. An image forming apparatus, wherein the image forming apparatus is the heating apparatus according to any one of the above.