JP2001324886A - Heating body, heating device, and image forming device - Google Patents

Abstract

PROBLEM TO BE SOLVED: To achieve improvement in the heat efficiency of a film heat type heating device and facilitation of management of parts. SOLUTION: A heating body 1 is fixedly supported to form a nip N together with a pressure member 6 via a slide film 4 and to heat an image on a recording material P being held and carried between the film 4 and a pressure member 6 in the nip N via the film 4. The heating body 1 has a base and a heating element which is provided on the base. The base has a projection (b) which projects toward the film sliding side in the area of the nip N and extends perpendicular to the direction in which the film is moved.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a film heating type heating device, a heating element used in the heating device, and a direct type or transfer type electrophotographic / electrostatic device equipped with the heating device as an image heating means. The present invention relates to an image forming apparatus (copying machine, printer, facsimile, etc.) of a recording system, a magnetic recording system and the like.

[0002]

2. Description of the Related Art A heating device of a film heating type is disclosed in
As described in JP-A-3-313182 and JP-A-2-157787, a nip is formed between a fixedly supported heating element, a film sliding on the heating element, and the heating element via the film. A pressure member, and a recording material (electrofax sheet, electrostatic recording sheet, transfer material sheet, printing paper, etc.) carrying an image between the nip film and the pressure member; In this configuration, an image on a recording material is heated by heat from a heating body via a film.

[0003] As the heating element, a ceramic heater or the like having a low heat capacity and a rapid temperature rise can be used, and a thin film having a small heat capacity can be used as a film. It has good quick-start properties (on-demand properties) and can realize energy-saving image heating.

This heating device can be used as a fixing device for heating and fixing an unfixed developer image (a toner image made of a heat-fusible resin or the like) to a recording material as a permanent fixed image, and a recording material carrying an image. It can also be used as an image heating device for improving the surface properties of gloss and the like by heating the same, and an image heating device for performing a temporary deposition process.

[0005]

In the above-described film-type heating apparatus, a ceramic heater as a heating element includes a ceramic substrate such as alumina as a heater base and a screen printing method or the like on the surface of the ceramic substrate. Silver-palladium (Ag
/ Pd) or the like as a basic constituent member. By reducing the thickness of the ceramic substrate as the heater base material, the heat capacity can be reduced, the startup time can be reduced, and the power consumption can be reduced.

Attempts are being made to replace the heater substrate with ceramic instead of metal. It has been attempted to reduce manufacturing costs. In the case of this metal substrate heater, the current-carrying heating element is provided on the substrate via an insulating layer by pattern formation by a screen printing method or the like.
Compared with ceramics, it is easier to handle in processing, and by reducing the thickness of the metal substrate as the heater base to a thickness equal to or less than the thickness of the conventional ceramic heater, heat capacity is reduced and startup time is reduced. This is effective in shortening the power consumption and power consumption.

However, in the case of a heater of a ceramic substrate and a heater of a metal substrate, when the thickness of the substrate is reduced to reduce the heat capacity, the strength of the substrate or the heating element alone decreases, The margin for bending / bending also decreases, and as a result, the margin for disconnection of the current-carrying heating element pattern also decreases, so that there is a problem that handling in parts management becomes difficult.

Accordingly, an object of the present invention is to provide a heating element used in a heating apparatus of a film heating system, in which the strength is not reduced even when the heat capacity is reduced by reducing the thickness of a heater substrate (heating element substrate). Strong against bending and bending
An object of the present invention is to provide a heating element which is easy to handle in distribution and parts management without causing a risk of disconnection of a current-carrying heating element pattern due to bending.

Another object of the present invention is to provide a heating device having the above-mentioned heating element, which has excellent durability and high heating efficiency (fixing efficiency).

Another object of the present invention is to provide an image forming apparatus provided with the above-mentioned heating device as an image heating means.

[0011]

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

(1) A nip is formed with a pressing member via a sliding film, which is fixed and supported, and an image of a recording material nipped and conveyed between the nip film and the pressing member is transferred through the film. A heating element for heating by heating, a base material, and a heating element provided on the base material, wherein the base material protrudes toward the film sliding surface in the nip region, and A heating element having a convex portion extending in a crossing direction.

(2) The heating element according to (1), wherein the convex portion is arranged outside the heating element region of the base material and on the downstream side in the recording material passing direction. Heating body.

(3) The heating element according to the above (1) or (2), wherein the material of the base is metal, and the heating element is formed on the base via an insulating layer. A heating element, characterized in that:

(4) The heating element according to any one of (1) to (3), wherein a metal plate is used as the base material, and the projections are formed by drawing or bending the metal plate. A heating element characterized by being formed.

(5) The heating element according to (1) or (2), wherein the material of the base is an insulating member, and the heating element is formed on the base. Heating body.

(6) The heating element according to any one of (1) to (5), wherein the heating element is formed by printing.

(7) A film of the nip, comprising a fixedly supported heating element, a film sliding on the heating element, and a pressure member forming a nip with the heating element via the film. And a pressurizing member, a heating device for nipping and conveying a recording material carrying an image, and heating an image on the recording material by heat from the heating body via the film, wherein the heating body has a base material And a heating element provided on the base material, wherein the base material has a protrusion protruding toward the film sliding surface in the nip region and extending in a direction intersecting with the film moving direction. A heating device.

(8) The heating device according to (7), wherein the convex portion of the heating element base material is disposed outside the heating element region of the base material and on the downstream side in the recording material passing direction. A heating device.

(9) The heating device according to the above (7) or (8), wherein the material of the heating base material is a metal,
A heating device, wherein the heating element is formed on the substrate via an insulating layer.

(10) The heating apparatus according to any one of (7) to (9), wherein a metal plate is used as the heating element base material, and the projections are formed by drawing or bending of the metal plate. A heating device characterized by being formed by:

(11) The heating device according to the above (7) or (8), wherein the material of the heating base material is an insulating member, and the heating element is formed on the base material. Characteristic heating device.

(12) The heating device according to any one of (7) to (11), wherein the heating element of the heating element is formed by printing.

(13) The heating device according to any one of (7) to (12), wherein the pressing member is a rotating body.

(14) An image forming apparatus having an image forming means for forming and carrying an image on a recording material and an image heating means for heating the recording material carrying the image, wherein the image heating means comprises (7)
An image forming apparatus, which is the heating apparatus according to any one of (1) to (13).

(Operation) The heating element has, on a part of its base material, a convex part having a ridge line extending in a direction intersecting with the film moving direction, so that the convex part acts as a reinforcing rib, and the base material for reducing heat capacity. Even if the plate thickness is reduced, the rigidity is maintained and the strength is not reduced, it is strong against bending and bending, and there is no risk of breaking the current-generating heating element pattern due to bending or bending.
It is easy to handle in logistics and parts management.

[0027] In addition, the convex portion is provided so as to protrude toward the film sliding surface side in the nip area,
An image (toner) melt-softened by heating in the nip is pressed against the recording material strongly in the above-mentioned convex portion without releasing excess heat to the back side of the heating body (the side opposite to the nip side) and in a molten state ( An instantaneous high pressure is applied to the toner melted on the recording material), so that the fixing efficiency is improved.

[0028]

DESCRIPTION OF THE PREFERRED EMBODIMENTS (First Embodiment) FIG. 1 is a schematic cross-sectional side view of a main part of a heating apparatus according to the present embodiment, FIG. FIG. 4 is a partially cutaway perspective model view of a main part of the apparatus, and FIG.

The heating device 18 of the present embodiment is disclosed in
Nos. 4075-44083 and 4-204980-2
No. 04984 discloses a tensionless type film heating type fixing device using a cylindrical film (endless film).

Reference numeral 1 denotes a slender, thin plate-like heating element (heating means) having a low heat capacity. The structure of the heating element will be described later. 2
Is a gutter-shaped film guide member formed of a heat insulating material and having a substantially semicircular cross-sectional shape. The heating element 1 is fitted and attached to a heating element accommodating recess 2a provided at a substantially central portion of the lower surface of the film guide member 2 along the longitudinal direction of the member. Reference numeral 3 denotes a U-shaped reinforcing stay having a downward cross section, which is fitted inside the film guide member 2. 4
Is a cylindrical heat-resistant film (fixing film). The inner peripheral length of the film 4 is longer than the outer peripheral length of the assembly of the heating element 1, the film guide member 2 and the reinforcing stay 3 by, for example, about 3 mm. 3 is loosely fitted to the outside.
Reference numerals 5.5 denote film end guides (flange members) mounted on both ends of the reinforcing stay 3, respectively. The above assembly 1 to 5 are referred to as a heating assembly (heating means).

Reference numeral 6 denotes an elastic pressure roller as a pressure rotating body. A core metal 6a and a rubber elastic layer 6b having good releasability such as silicon rubber provided concentrically and integrally with the core metal;
The two ends of a are rotatably supported between front and rear chassis side plates (not shown) of the apparatus via bearings.

On the upper side of the pressure roller 6, the above-mentioned heating assemblies 1 to 5 are arranged so that the heating body 1 side faces downward, and the outwardly projecting portions of the film end guides 5.5 on both ends are respectively located in front of the apparatus (not shown). The heating element 1 is engaged with the longitudinal guide slits of the side and rear chassis side plates and dropped between the front and rear chassis side plates. With the downward facing surfaces facing each other.

Then, each film end guide 5 at both ends is provided.
By pressing the pressure springs 8.8 between the outwardly protruding portions 5 and the immovable spring receiving portions 7.7 above, the heating element 1 sandwiches the film 4. Pressure roller 6
Against a total pressure of about 39 to 1 against the elasticity of the rubber elastic layer 6b.
It is pressed at 96 N (4 to 20 kgf). As a result, a nip (fixing nip) N having a predetermined width is formed with the film 4 interposed between the heating body 1 and the pressure roller 6. The nip N has a substantially uniform width over the entire length of the pressure roller 6 or the heating element 1 in the longitudinal direction. That is, the reinforcing stay 3 is pressed from directly above via the film end guides 5 at both ends of the reinforcing stay 3 so as to prevent bending from occurring in the entire nip. The nip line does not bend and becomes an ideal straight line N1 (FIG. 2) without bending. At this time, the nip width WN is uniform, and the toner fixability is assured uniformly in the paper width direction.

The film 4 has a total film thickness of 100 μm or less, preferably 50 μm or less and 30 μm or more, in order to reduce the heat capacity and improve the quick start property, such as heat resistance, releasability, strength and durability. PTFE,
There is a single layer film such as PFA, a composite layer film in which the surface of a film such as polyimide, polyamide imide, PEEK, PES, PPS, etc. is coated with PTFE, PFA, FEP, etc. as a release layer, or a seam using metal foil. Or a seamless metal tube.

The pressure roller 6 is driven to rotate at a predetermined peripheral speed in a counterclockwise direction indicated by an arrow in FIG. Due to the friction between the outer surface of the roller and the outer surface of the film 4 due to the rotation of the pressure roller 6 at the nip N, a rotational force acts on the cylindrical film 4 so that the inner surface of the film 4 is nipped. In N, the film guide member 2 and the reinforcing stay 3 are rotated in a clockwise direction indicated by an arrow at a peripheral speed substantially corresponding to the rotational peripheral speed of the pressure roller 6 while sliding in close contact with the downward surface of the heating element 1. (Pressure roller drive system).

The outer surface of the film guide member 2 and the film 4
The rotation of the film 4 can be made smoother by interposing a lubricating material such as grease between the film 4 and the inner surface of the film 4. Film guide member 2 accompanying rotation of film 4
Is regulated by the end of the film 4 being received by the inner surface of the guide 5.

The pressure roller 6 is driven to rotate, and the cylindrical film 4 is rotated accordingly, and the heating element 1 is energized as will be described later.
In a state where the temperature rises to a predetermined temperature and is controlled,
The recording paper P carrying the unfixed toner image T is introduced between the film 4 of the nip N and the pressure roller 6, and the toner image carrying surface side of the recording paper P is brought into close contact with the outer surface of the film 4 in the nip N, The nip N is conveyed together with the nip N4. In the nipping and conveying process, the heat of the heating element 1 is applied to the recording paper P via the film 4, and the unfixed toner image T on the recording paper is heated and fused. When the recording paper P passes through the nip N, the recording paper P is conveyed with a curvature separated from the outer surface of the rotating film 4.

The structure of the heating element 1 will be described below. The heating element 1 in the present embodiment is of a type using a metal plate as a heating element base material. The metal material used is, for example, an iron-based metal represented by stainless steel, aluminum, a copper alloy, or the like.

FIG. 5A is a partially cutaway plan model diagram on the front side of the heating body, FIG. 5B is a plan model diagram on the back side of the heating body,
(C) is an enlarged cross-sectional model diagram along the line cc in FIG.

A is the film moving direction (recording paper passing direction)
And a metal plate base member having a longitudinal direction substantially perpendicular to. W is the width of the metal plate substrate a, and has a relationship of WN ≒ W with respect to the nip width WN. b is a bead (ball edge) formed by metal plate drawing as a convex portion provided along the length of the metal plate base material a. The bead b is provided so as to protrude on the surface side of the heating element 1, that is, on the film sliding surface side (recording paper side). The protrusion amount is, for example, 1 mm or less.

C is an insulating layer covering the surface side of the metal plate base material b, and d is a linear or narrow strip formed on the insulating layer c along the length of the base material, and is a heat generating source as a heat source. Body (resistance heating element).

Reference numeral e denotes a linear or narrow strip-shaped power supply path provided on the insulating layer c in parallel with the current-carrying heating element d along the length of the base material.

F and g are first and second power supply electrodes arranged side by side on the insulating layer c at one end of the base material in the longitudinal direction, and the first power supply electrode f is connected to one end of the current-carrying heating element d. Electrically conductive. The second power supply electrode g is electrically connected to one end of the power supply path e. The other end of the power supply heating element d and the other end of the power supply path e are electrically connected to each other.

Reference numeral h denotes an electrically insulating overcoat layer made of glass or the like as a surface protective layer covering the entire surface of the heating body except for the first and second power supply electrodes f and g.

I is a temperature detecting element such as a thermistor provided in contact with the back side (back side) of the heating element 1, and j is a temperature detecting element for safety measures (thermal element) also provided in contact with the back side of the heating element 1. Thermal fuses and thermoswitches as measures against runaway temperature rise due to failure of protectors and devices.

The electric heating element d is made of, for example, an electric resistance material paste (resistance paste) such as silver-palladium (Ag / Pd) or Ta ₂ N, for example, with a thickness of 10 μm and a width of 1-3 mm.
It is formed by applying to the narrow band-shaped pattern by screen printing or the like and firing.

The power supply path e and the first and second power supply electrodes f and g
Also, for example, it is formed by applying a silver (Ag) paste in a required pattern by screen printing or the like and firing it.

The overcoat layer h side of the heating element 1 is the surface on which the film slides. The heating element 1 has its front surface exposed to the outside, and is fitted and attached to a heating element accommodating recess 2 a provided along the longitudinal direction of the film guide member 2 at a substantially central portion of the lower surface thereof.

Reference numeral 9 denotes a power supply connector for the current-carrying heating element d of the heating element 1, which is fitted to an end of the film guide member 2 on which the heating element 1 is mounted, on the side of the heating element power supply electrode. Although the connector 9 is arranged to be inserted in parallel with the longitudinal direction of the heating element, the connector 9 may be arranged in a direction perpendicular to the longitudinal direction after the first and second power supply electrodes f and g are routed.

An AC power supply 10 (FIG. 4) between the first and second power supply electrodes f and g of the heater 1 via the power supply connector 9.
A higher voltage is applied, and the heating element 1 heats up as the energized heating element d generates heat. The temperature of the heating element 1 is detected by a temperature detecting element i on the back surface of the heating element base material a, and the detection information is fed back to the energization control circuit 11 to control the energization from the AC power supply to the energizing heating element d. The temperature is controlled so that the temperature of the heating element 1 detected by the temperature detecting element i at the time of fixing execution becomes a predetermined temperature (fixing temperature).

The temperature fuse or the thermoswitch j is inserted in series in a power supply circuit for the heating element d.
It operates when the temperature of the heating element 1 exceeds an unacceptable excessive temperature, and the power supply to the energizing heating element d is urgently cut off.

In the heating element 1 of this embodiment, metal is used as the heating element base material a, and the thickness of the part is reduced, and a bead b is formed as a convex part. As a result, the warpage strength of the current-carrying heating element d in a single product state is assured, fixing of the current-carrying heating element d is prevented from being broken or bent over the entire length, while improving fixing efficiency and reducing power consumption. That is, even if a metal is used as the heating element base material a and the heat capacity is reduced by reducing its thickness, the strength is not reduced by the reinforcement by the bead b, and it is strong against bending and bending, There is no danger of breaking the current-carrying heating element pattern due to bending or bending, and it is easy to handle in terms of component management.

The heating element base material a has a bead b as a convex portion extending in a direction intersecting the recording paper passing direction within the nip width WN on the downstream side of the heating element d in the recording paper passing direction. And slides without hitting the edge with the film 4,
The melted toner is pressed against the recording paper via the film 4. That is, the recording material P that has passed through the position of the current-carrying heating element d in the nip N is loaded with the molten toner, and the nip N
Reaches the bead b inside, and is momentarily strongly pressed against the recording paper, thereby improving the fixing efficiency. At this time, the inner peripheral surface of the film 4 and the bead b are provided with a curved surface portion at the tip of the bead so as not to hit the edge, and the inner peripheral surface of the film is damaged by applying a lubricant to the inner peripheral surface of the film. Can rub each other without suffering.

As shown in the example of FIG. 6, the overcoat layer h of the heating element 1 may be provided so as to cover only the surface portions of the electric heating element d and the power supply path e, and the same effect can be obtained.

A bead b serving as a protrusion provided on a metal substrate a as a heating base material can easily process a plurality of base materials at the same time in one press working step in mass production of a component. Can be pressed against the recording paper, and the edge contact with the film can be avoided.

(Second Embodiment) FIG. 7 is an enlarged schematic cross-sectional view of the heating element 1 of this embodiment. In the heating element 1 of this embodiment, a convex portion b provided on a metal plate base material a is formed by hemming (bending a metal plate). The other configuration of the heating element is the same as that of the above-described heating element in the first embodiment, and thus the description thereof will not be repeated.

Also in the case of this example, the heating element base material a is a metal plate, and is thinned and reinforced by hemming.
In a single product state, the current-carrying heating element d hardly breaks due to bending or bending, and is easy to handle.

The recording material P, which has passed the position of the current-carrying heating element d in the nip N, places the melted toner thereon, reaches a bead b as a convex portion in the nip N, is momentarily strongly pressed against the recording paper, and is fixed. Efficiency is improved. At this time, film 4
The inner peripheral surface and the hemming bent portion b do not hit the edge by filling the minute step portion α with the glass coat layer as the overcoat layer h. Also, by using a lubricant, the inner peripheral surfaces of the films can be rubbed without being damaged.

The overcoat layer h of the heating element 1 may be provided so as to cover only the surface portions of the electric heating element d and the power supply path e as in the example of FIG. 8, and the same effect is obtained.

(Third Embodiment) FIG. 9 is an enlarged schematic cross-sectional view of the heating element 1 of the present embodiment. The heating element 1 of this embodiment uses a heat insulating material such as a ceramic as a heating element base material a, and a nip N
In order to instantly and strongly press the toner, which has been melted in the inside, against the recording paper, a projection b is provided over the entire region in the longitudinal direction of the base material a. The ridgeline of the convex portion protrudes into the nip N. The insulating layer c is unnecessary. The other configuration of the heating element is the same as that of the above-described heating element in the first embodiment, and thus the description thereof will not be repeated.

Also in the case of this example, the thinning and the reinforcement by the convex portion b are made, and the electric heating element d is hard to be broken due to bending or bending in a single product, and is easy to handle.

The recording material P, which has passed the position of the current-carrying heating element d in the nip N, carries the melted toner, reaches the convex portion b in the nip N, is instantly and strongly pressed against the recording paper, and improves the fixing efficiency. I do. At this time, the inner peripheral surface of the film 4 and the protruding portion b do not have an edge portion, and can be rubbed without damage to the inner peripheral surface of the film by using a lubricant.

As shown in the example of FIG. 10, the overcoat layer h of the heating element 1 may be provided so as to cover only the surface portions of the electric heating element d and the power supply path e, and the same effect is obtained.

(Fourth Embodiment) 1) With respect to the heaters of the first and second embodiments, as shown in FIGS. 11A and 11B, the metal plate of the heater 1 A structure (back surface heating type) having a heating element d, a power supply path e, and power supply electrodes f and g on the back side of the base material a with an insulating layer c interposed therebetween may be used.

2) As for the heating element of the third embodiment, as shown in FIG. 11C, as the heating element substrate a, a high heat source such as aluminum nitride (AlN) / silicon carbide (SiC) is used. It is also possible to use a conductive ceramic and have a structure in which an electric heating element d, a power supply path e, and power supply electrodes f and g are provided on the back side.

3) Electric heating element d, power supply path e, power supply electrode f
The pattern configuration such as g and the configuration of the heating device are not limited to those of the embodiment.

4) Needless to say, the arrangement positions of the temperature detecting element i for temperature control and the temperature detecting element j for safety measures are not limited to those of the embodiment. For example, the temperature detection element i for temperature control may be arranged outside the film passing area and near the sheet passing heat generating element and immediately outside the film. If the film is a metal cylinder, it may be disposed on the inner peripheral surface after performing necessary insulation.

(Fifth Embodiment) FIG. 12 is a schematic structural view of an example of an image forming apparatus provided with, for example, a heating device (fixing device) 18 of the first embodiment. The image forming apparatus of the present embodiment is a laser beam printer using a transfer type electrophotographic process.

A process cartridge 11 is detachable from the printer main body, and includes a photosensitive drum 12, a charger, a developing device, and a cleaning device (not shown).
The photosensitive drum 1 is driven to rotate at a predetermined peripheral speed in the clockwise direction of the arrow, and a toner image corresponding to target image information is formed on the peripheral surface thereof by a known electrophotographic process. 13
A laser transmitting device (scanner) as an image exposing device for the photosensitive drum 12 is a laser beam intensity-modulated according to a time-series electric digital pixel signal of image information input and transmitted from a personal computer (PC) or the like. Is output to scan and expose the charged surface of the photosensitive drum 12 to form an electrostatic latent image of image information.

On the other hand, the recording paper (transfer material) P loaded and stored in the paper feed cassette 14 is fed one by one by the operation of the paper feed roller 15, conveyed by the conveyance roller 16, and transferred to the photosensitive drum 12. The toner image on the photosensitive drum 12 side is sequentially transferred to the transfer portion, which is a pressure contact nip portion of the roller 17, at a predetermined control timing.

The recording paper P that has passed through the transfer unit is
Will be introduced. The fixing device 18 is, for example, a film heating type heating device of the first embodiment, and heats and fixes the toner image as described above.

The recording paper P exiting from the fixing device 18 is discharged face-down to a discharge tray 21 through a fixing discharge roller 19 and a sheet path 17. Alternatively, the fixing discharge roller 1
9. The sheet is discharged face-up to the rear of the printer through the sheet path 22.

The sheet jam in the sheet paths 20 and 21 is processed by opening the rear unit 23 of the printer as shown by a two-dot chain line and opening the rear portion of the printer. 24
Is a main motor of the printer.

[0074]

As described above, according to the present invention, the strength of the heating element used in the film-type heating apparatus can be reduced even when the heat capacity is reduced by reducing the thickness of the substrate of the heating element. Without breaking and bending
It is possible to provide a heating element which is easy to handle in terms of component management without causing a risk of disconnection of the energization heating element pattern due to bending.

Further, by providing the above-mentioned heating element, it is possible to provide a heating device having excellent durability and high heating efficiency (fixing efficiency).

Further, it is possible to provide an image forming apparatus of an electrophotographic system, an electrostatic recording system or the like, which is provided with the above-mentioned heating device as an image heating means.

[Brief description of the drawings]

FIG. 1 is a schematic cross-sectional side view of a main part of a heating device (fixing device) according to a first embodiment.

FIG. 2 is a longitudinal sectional front view of a main part of the apparatus.

FIG. 3 is a partially cutaway perspective view of a main part of the apparatus.

FIG. 4 is an exploded perspective view of the model.

5 (a) is a partially cutaway plan view of the front side of the heating element, FIG. 5 (b) is a plan view of the rear side of the heating element, and FIG. 5 (c) is taken along line cc in FIG. Enlarged cross-sectional model diagram along

FIG. 6 is an enlarged cross-sectional model diagram of another configuration example of the heating element.

FIG. 7 is an enlarged cross-sectional model diagram of a heating element according to a second embodiment.

FIG. 8 is an enlarged cross-sectional model diagram of another configuration example of the heating element.

FIG. 9 is an enlarged cross-sectional model view of a heating element according to a third embodiment.

FIG. 10 is an enlarged cross-sectional model diagram of another configuration example of the heating element.

FIGS. 11 (a), (b) and (c) are enlarged cross-sectional model views of the heating element of the fourth embodiment, respectively.

FIG. 12 is a schematic diagram illustrating a configuration of an image forming apparatus according to a third embodiment.

[Explanation of symbols]

1. Heating body 2. Film guide member 3. Reinforcement stay 4. Cylindrical film (fixing film) 5.
・ Film end guide, 6 ・ ・ Pressure roller, N ・ ・ Nip, P ・ ・ Recording material, a ・ ・ Heating material base material, b ・ ・ Protrusion, c
..Insulating layers, d, e.
..First power supply electrode, g.second power supply electrode

 ──────────────────────────────────────────────────続 き Continued on the front page F term (reference) 2H033 BA11 BA27 BE03 3K058 AA02 BA18 CE13 CE19 DA04 GA06 3K092 PP18 QA05 QB02 QB12 QB30 QB76 RF03 RF09 RF17 RF22 VV16 VV40

Claims (14)

[Claims] An image of a recording material which is fixedly supported and forms a nip with a pressing member via a sliding film, and an image of a recording material nipped and conveyed between the film of the nip and the pressing member via the film. A heating element for heating, comprising a base material and a heating element provided on the base material, wherein the base material protrudes toward the film sliding surface in the nip region and intersects with the film moving direction. A heating element having a convex portion extending in a direction in which the heating element extends. 2. The heating element according to claim 1, wherein the convex portion is arranged outside a heating element region of the base material and on a downstream side in a recording material passing direction. body. 3. The heating element according to claim 1, wherein a material of the base is metal, and the heating element is formed on the base via an insulating layer. Heating body. 4. The heating element according to claim 1, wherein a metal plate is used as the base material, and the convex portion is formed by drawing or bending the metal plate. A heating element characterized in that: 5. The heating element according to claim 1, wherein said base material is an insulating member, and said heating element is formed on said base material. 6. The heating element according to claim 1, wherein the heating element is formed by printing. 7. A fixedly supported heating element, a film that slides on the heating element, and a pressing member that forms a nip with the heating element via the film. In a heating device that sandwiches and conveys a recording material carrying an image between a pressing member and heats an image on the recording material by heat from the heating body through the film, the heating body includes a base material Having a heating element provided on the base material, the base material protruding toward the film sliding surface in the nip region, and having a convex portion extending in a direction intersecting with the film moving direction. Characteristic heating device. 8. The heating device according to claim 7, wherein the convex portion of the heating base material is disposed outside the heating element region of the base material and on the downstream side in the recording material passing direction. A heating device. 9. The heating device according to claim 7, wherein a material of the heating element base is metal, and the heating element is formed on the base via an insulating layer. Characteristic heating device. 10. The heating device according to claim 7, wherein a metal plate is used as the heating base material,
The said convex part is formed by the drawing process or bending process of this metal plate, The heating apparatus characterized by the above-mentioned. 11. The heating device according to claim 7, wherein a material of the heating body base is an insulating member, and the heating element is formed on the base. apparatus. 12. The heating device according to claim 7, wherein the heating element of the heating element is formed by printing. 13. The heating device according to claim 7, wherein the pressing member is a rotating body. 14. An image forming apparatus comprising: an image forming means for forming and carrying an image on a recording material; and an image heating means for heating the recording material carrying the image, wherein said image heating means is one of claims 7 to 13. An image forming apparatus, which is the heating apparatus according to any one of the above items.