JPH10198200A - Heating device and image forming device - Google Patents

Abstract

PROBLEM TO BE SOLVED: To excellently circulate a lubricant, for preventing the increase of rotational torque caused by endurance and further, to prevent the occurrence of the stepping out of a driving roller and a failure in jamming, etc., even if the prolongation of the life of a device is attempted by providing a groove in a part, for forming a nip together with a pressure member, with a film. SOLUTION: The sigmoid groove 11 having a fixed width and depth is formed in the part, corresponding to a fixing nip part N of a film guide 2a. In such a case, the groove 11 is formed at an equal interval in a longitudinal direction by machining, etc., to make the total area of the groove 11 into 5-50% of the area of the surface corresponding to the fixing nip part N. This groove 11 is provided so that the lubricant interposed between the film guide 2a and the inside surface of the fixing film 1 is stably circulated and supplied enduringly, to reduce the mutual sliding frictional force between the film guide 2a and the inside surface of the fixing film 1, in the fixing nip part N. Thus, a heating device capable of increasing speed and prolonging the life can be obtained.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

TECHNICAL FIELD The present invention relates to a method for pressurizing a material to be heated.
The present invention relates to a heating apparatus for heating and an image forming apparatus such as an electrophotographic apparatus and an electrostatic recording apparatus provided as an image heating apparatus for heating and fixing an unfixed image formed and carried on a recording material.

[0002]

2. Description of the Related Art For convenience, an image heating apparatus (fixing apparatus) provided in an image forming apparatus such as a copying machine or a printer for heating and fixing a toner image on a recording material will be described as an example.

In an image forming apparatus, a recording material (transfer material sheet, electrofax sheet, electrostatic recording paper, OHT (OHP)) is used by an appropriate image forming process means such as an electrophotographic process, an electrostatic recording process, and a magnetic recording process. )
A fixing device that heats and fixes an unfixed image (toner image) of target image information formed on a sheet, printing paper, format paper, and the like by a transfer method or a direct method as a permanently fixed image on a recording material surface is used. Heat roller type devices have been widely used. Recently, a film heating type apparatus has been put into practical use. Also, an electromagnetic induction heating system has been proposed.

[0004] a) Heat roller system [0004] The heat roller system basically has a pressure roller pair of a fixing roller (heating roller) and a pressure roller, and rotates the roller pair to form a fixing nip portion which is a mutual pressure contact portion of the roller pair. The recording material on which an unfixed toner image to be image-fixed is formed and carried is introduced into the (heating nip portion), and is nipped and conveyed. The unfixed toner image is formed by the heat of the fixing roller and the pressing force of the fixing nip portion. The fixing is performed by heat and pressure on the surface of the recording material.

[0005] The fixing roller generally has a hollow metal roller made of aluminum as a base (core metal), and a halogen lamp as a heat source is inserted and disposed in the inner space thereof. The power supply to the halogen lamp is controlled to control the temperature so that the predetermined fixing temperature is maintained.

Particularly, as a fixing device of an image forming apparatus for forming a full-color image, which is required to have a capability of sufficiently heating and melting a maximum of four toner image layers to mix colors,
If not sufficiently heated to the interface between the recording material and the toner layer, a fixing failure occurs, so the core of the fixing roller has a high heat capacity, and the toner image is wrapped around the core and melted uniformly. A rubber elastic layer for
The toner image is heated via the rubber elastic layer. There is also a configuration in which a heat source is provided in the pressure roller so that the pressure roller is also heated and controlled in temperature.

B) Film heating system A fixing device of the film heating system is disclosed in, for example, JP-A-63-3
Japanese Patent Application Laid-Open No. 13182, Japanese Patent Application Laid-Open No. 2-1577878, Japanese Patent Application Laid-Open No. 4-44075, Japanese Patent Application Laid-Open No. 4-204980, and the like.

That is, a nip portion is formed by sandwiching a heat-resistant film (fixing film) between a generally ceramic heater as a heating element and a pressing roller as a pressing member. By introducing a recording material on which an unfixed toner image to be image-fixed is formed and carried between the pressure roller and holding and transporting the recording material together with the film, the heat of the ceramic heater is recorded via the film in the nip portion through the film. The unfixed toner image is heated and fixed on the surface of the recording material by applying pressure to the material and applying pressure at the nip portion.

This film heating type fixing device can be constituted as an on-demand type device using a ceramic heater and a member having a low heat capacity as a film, and a ceramic heater as a heat source only when the image forming apparatus executes image formation. To a state in which heat is generated to a predetermined fixing temperature, the waiting time from the power-on of the image forming apparatus to the image forming executable state is short (quick start property), and the power consumption during standby is greatly reduced. There are advantages such as small (power saving).

C) Electromagnetic induction heating system Japanese Patent Application Laid-Open No. Hei 7-114276 proposes a heating device that generates an eddy current in a film itself or a conductive member close to the film and generates heat by Joule heat. In this electromagnetic induction type / film heating method, the heat generation area can be made closer to the object to be heated, so that the efficiency of energy consumption can be increased.

In a film-type heating device, a cylindrical or endless belt-shaped film as a rotating body is driven by pressing a film pressed by a film guide for guiding the inner peripheral surface of the film and a pressure roller. There are a method in which the roller is driven to rotate by rotation (pressure roller driving method), and a method in which the pressure roller is driven to rotate by driving an endless belt-like film stretched by a driving roller and a tension roller.

A lubricant such as heat-resistant grease is interposed between the inner surface of the film and the film guide in order to reduce the influence of rotational torque caused by friction between the film and the film guide.

When fixing a medium such as an OHT which requires transparency, the process speed is reduced so that sufficient pressure and heating are performed in order to secure transparency.

Further, when fixing a color image or the like on thick paper or the like, in order to secure the fixing property, the process speed is reduced so that sufficient pressure and heating are performed.

[0015]

However, the above-described film heating type heating device (fixing device) has the following problems.

1) Depending on the material of the film or the film guide, the rotational torque tends to increase as the number of prints increases. That is, as the number of prints increases, the film or the film guide is gradually shaved due to sliding friction and the like, and the lubricant is deteriorated due to the shavings and the like, and circulation is deteriorated. As a result, the mutual friction force between the film and the film guide increases, and the rotational torque increases. Therefore, when the speed of the apparatus is increased or the life of the apparatus is to be extended, problems such as a failure in stepping of the drive motor and a failure in paper conveyance due to poor film follow-up due to an increase in torque (fixing jam). Occurs. In an extreme case, there was a problem that the film was damaged.

2) When the pressing force is increased in order to further improve the transparency of OHT and the fixing property of thick paper, or
When an attempt is made to increase the pressing force in order to increase the process speed of fixing HT or thick paper, problems such as a step-out of the drive motor and a fixing jam occur due to an increase in rotational torque.

Therefore, according to the present invention, in a film heating type heating device (image heating device, fixing device) using a cylindrical or endless belt-like film as a rotating body, torque increase due to durability is prevented and the drive motor is removed. It is an object of the present invention to provide an apparatus capable of increasing the speed and extending the life of the recording medium without causing any troubles such as tone, jam of a recording material, or deterioration of durability of a film.

In use as an image heating device,
It is an object of the present invention to provide an apparatus capable of realizing an improvement in fixing property and an improvement in transparency or an increase in speed even when fixing a medium requiring transparency or a high gloss medium.

[0020]

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

(1) It has a rotating body, a pressing member for pressing the rotating body, and a supporting member for supporting the rotating body, and is covered by a contact portion formed by the contact between the rotating body and the pressing member. In a heating device that pressurizes and heats a material to be heated by sandwiching and transporting a heating material, a portion of a support member that supports a rotating body corresponds to a contact portion formed by contact between the rotating body and the pressing member. A heating device, provided with a groove.

(2) The groove according to (1), wherein the groove is formed so as to occupy 5 to 50% of an area of a contact portion formed by contact between the rotating body and the pressing member. Heating equipment.

(3) The groove has a width of 0.1 to 1.5 mm,
Characterized in that the depth is 0.1 to 0.5 mm (1)
Or the heating device according to (2).

(4) The heating device according to any one of (1) to (3), wherein the grooves are arranged obliquely to a traveling direction of the material to be heated.

(5) It has a rotating body, a pressing member for pressing the rotating body, and a supporting member for supporting the rotating body, and is covered by a contact portion formed by the contact between the rotating body and the pressing member. In a heating device that pressurizes and heats a material to be heated by sandwiching and transporting a heating material, a portion of a support member that supports a rotating body corresponds to a contact portion formed by contact between the rotating body and the pressing member. A heating device provided with at least one projection.

(6) The height of the projection from the contact surface formed by the contact between the rotating body and the pressing member is 0.1.
The heating device according to (5), wherein the width is 5 mm to 1 mm and the width is 5 to 60% of the width of the contact surface.

(7) The projection is arranged obliquely with respect to the traveling direction of the material to be heated (5) or (6).
A heating device according to claim 1.

(8) It has a rotating body, a pressing member for pressing the rotating body, and a supporting member for supporting the rotating body, and is covered by a contact portion formed by the contact between the rotating body and the pressing member. In a heating device that presses and heats a material to be heated by sandwiching and transporting a heating material, a portion of a support member that supports a rotating body corresponds to a contact portion formed by contact between the rotating body and the pressing member. A heating device characterized in that the pressure is locally increased.

(9) It has a rotating body, a pressing member for pressing the rotating body, and a supporting member for supporting the rotating body, and is covered by a contact portion formed by the contact between the rotating body and the pressing member. In a heating device that presses and heats a material to be heated by sandwiching and transporting a heating material, a portion of a support member that supports a rotating body corresponds to a contact portion formed by contact between the rotating body and the pressing member. A heating device, wherein the heating device is formed in a concave shape having a diameter smaller than the outer diameter of the pressing member.

(10) An electromagnetic induction heating member, a first member having a magnetic field generating means for generating a magnetic field by applying a magnetic field to the electromagnetic induction heating member, and mutually press-contacting the first member directly or with another member interposed therebetween. A second member forming a nip portion, and applying heat energy to the material to be heated introduced into the nip portion and nipped and conveyed by heat generated by the electromagnetic induction heating member to heat the material to be heated (1) The heating device according to any one of (1) to (9).

(11) The heat-resistant film is brought into close contact with the heating member with a pressing member and is slid and rotated, and the material to be heated is placed in a pressing nip portion formed by the heating member and the pressing member with the heat-resistant film interposed therebetween. And heat is applied to the object to be heated through the heat-resistant film to heat the material to be heated (1) to (9).
The heating device according to any one of the above.

(12) The material to be heated is a recording material on which an unfixed image is formed and carried, and the apparatus is a heat fixing device for heating and fixing the unfixed image on the recording material.
The heating device according to any one of (1) to (11).

(13) An image forming means for forming and carrying an unfixed image on the recording material, and a fixing means for fixing the unfixed image formed and carried on the recording material, wherein the fixing means (1) to ( 1
An image forming apparatus, which is the heating apparatus according to any one of 1) and 2).

(14) An image carrier as a member to be charged, charging means for charging the image carrier, exposure means for exposing the image carrier to form an electrostatic latent image, and Developing means for attaching a toner to an image to form a toner image; transfer means for transferring the toner image on the image carrier to a transfer material; and fixing means for making the toner image transferred to the transfer material a permanent fixed image An image forming apparatus comprising: the heating device according to any one of (1) to (11).

<Operation> By providing the groove on the nip surface as described above, it is possible to circulate the lubricant stably through the durability, prevent the torque from increasing due to the durability, and improve the driving motor. It is possible to increase the speed and extend the life of the apparatus without causing any trouble such as step-out or fixing jam.

Further, by employing a configuration in which a projection is provided at the nip portion, it is possible to locally increase the pressing force and to improve the fixing property and the transmittance without increasing the total pressing force. Becomes

[0037]

BEST MODE FOR CARRYING OUT THE INVENTION

<Embodiment 1> (FIGS. 1 to 9) (1) Example of Image Forming Apparatus FIG. 1 is a schematic configuration diagram of an example of an image forming apparatus. The image forming apparatus of this embodiment is a four-color image printer utilizing an electrophotographic process.

Reference numeral 101 denotes an electrophotographic photosensitive drum (image bearing member) made of an organic photosensitive member or an amorphous silicon photosensitive member, and is driven to rotate counterclockwise as indicated by an arrow at a predetermined process speed (peripheral speed).

The photosensitive drum 101 undergoes a uniform charging process of a predetermined polarity and potential by a charging device 102 such as a charging roller during its rotation.

Next, a laser beam 103 output from a laser optical box (laser scanner) 110 is provided on the charged surface.
And scanning exposure processing of the target image information. The laser optical box 110 outputs laser light 103 modulated (on / off) in response to a time-series electric digital pixel signal of target image information from an image signal generator such as an image reader (not shown), and The drum surface is subjected to scanning exposure, and the scanning exposure forms an electrostatic latent image corresponding to the target image information scanned and exposed on the rotating photosensitive drum 101 surface. 10
Reference numeral 9 denotes a mirror for deflecting the output laser light from the laser optical box 110 to the exposure position of the photosensitive drum 101.

In the case of forming a full-color image, scanning exposure and latent image formation are performed on a first color-separated component image of a target full-color image, for example, a yellow component image. Is developed as a yellow toner image by the operation of the yellow developing device 104Y. The yellow toner image is transferred onto the surface of the intermediate transfer drum 105 at a primary transfer portion T1 which is a contact portion (or a close portion) between the photosensitive drum 101 and the intermediate transfer drum 105. After the transfer of the toner image to the surface of the intermediate transfer drum 105, the surface of the rotating photosensitive drum 101 is
7 removes adhered residues such as transfer residual toner and is cleaned.

The above-described process cycle of charging, scanning exposure, development, primary transfer, and cleaning is performed by the second color separation component image (for example, magenta component image, magenta developing unit 104M operates) of the target full-color image. The color separation component images of a third color component image (for example, a cyan component image and the cyan developing device 104C are activated) and a fourth color component image (for example, a black component image and the black developing device 104BK are activated) are sequentially executed. A four-color toner image of a yellow toner image, a magenta toner image, a cyan toner image, and a black toner image is sequentially superimposed and transferred onto the surface of the intermediate transfer drum 105, and a color toner image corresponding to a target full-color image is synthesized and formed. Is done.

The intermediate transfer drum 105 has a medium-resistance elastic layer and a high-resistance surface layer on a metal drum, and has substantially the same peripheral speed as the photosensitive drum 101 in contact with or close to the photosensitive drum 101. Is rotated clockwise as indicated by an arrow, and a bias potential is applied to the metal drum of the intermediate transfer drum 105 so that a toner image on the photosensitive drum 101 side is applied to the surface of the intermediate transfer drum 105 by a potential difference from the photosensitive drum 101. Transfer to

The color toner image synthesized and formed on the surface of the intermediate transfer member 105 is
In the secondary transfer portion T2, which is a contact nip portion between the recording material P and the transfer roller 106, the image is transferred to the surface of the recording material P sent to the secondary transfer portion T2 from a paper supply unit (not shown) at a predetermined timing. . The transfer roller 106 supplies a charge having a polarity opposite to that of the toner from the rear surface of the recording material P, thereby sequentially transferring the combined color toner images collectively from the surface of the intermediate transfer drum 105 to the recording material P.

The recording material P that has passed through the secondary transfer portion T2 is separated from the surface of the intermediate transfer drum 105, introduced into the image heating device (fixing device) 100, and subjected to the heat fixing process of the unfixed toner image. The sheet is discharged to a discharge tray (not shown) outside the apparatus as a color image formed product. The fixing device 100 will be described in detail in the following section (2).

After the transfer of the color toner image to the recording material P, the rotating intermediate transfer drum 105 is cleaned by the cleaner 108 by removing the adhered residues such as untransferred toner and paper dust. The cleaner 108 is normally kept in a non-contact state with the intermediate transfer drum 105, and is kept in contact with the intermediate transfer drum 105 in the process of performing the secondary transfer of the color toner image from the intermediate transfer drum 105 to the recording material P. Is held.

Further, the transfer roller 106 is always kept in a non-contact state with the intermediate transfer drum 105, and during the secondary transfer of the color toner image from the intermediate transfer drum 105 to the recording material P, the intermediate transfer member Drum 10
5 is held in contact with the recording material P via the recording material P.

A print mode of a monocolor image such as a black and white image can also be executed. Also, a double-sided image print mode or a multiple image print mode can be executed.

In the case of the double-sided image print mode, the recording material P on which the first-side image has been printed out of the fixing device 100 is turned upside down via a recirculation transport mechanism (not shown), and is again sent to the secondary transfer portion T2. Then, the toner image is transferred to the two surfaces, and the toner image is again introduced into the fixing device 100 and subjected to the fixing process of the toner image to the two surfaces, whereby a double-sided image print is output.

In the case of the multiple image print mode, the recording material P on which the first image has been printed out of the fixing device 100 is not turned upside down via a recirculation transport mechanism (not shown) and is returned to the secondary transfer portion T2 again. The multi-image print is output by receiving the second transfer of the toner image on the surface on which the first image print has been performed and then re-introduced to the fixing device 100 to undergo the second toner image fixing process.

(2) Fixing Apparatus 100 A) Overall Schematic Configuration of Apparatus 100 The fixing apparatus 100 of this embodiment is an apparatus of a pressure roller driving system and an electromagnetic induction heating system using a cylindrical electromagnetic induction heating film. is there.

FIG. 2 is a front model diagram of the apparatus 100 with an intermediate portion omitted, FIG. 3 is a vertical sectional model diagram with an intermediate portion omitted, and FIG. 4 is a cross-sectional model diagram.

Reference numerals 2a and 2b denote lower and upper horizontally long film guides, each of which is a trough-shaped molding member having a substantially semicircular cross section. For example, it is a rigid molded product made of a heat-resistant resin. Lower film guide 2a with opening side facing upward
The upper film guide 2b with the opening side facing downward is overlapped with the upper film guide 2b to form a substantially cylindrical, horizontally long film guide composed of the two film guides 2a and 2b.

Reference numerals 3 and 4 denote a horizontally-long boat-shaped exciting coil and a T-shaped magnetic core (exciting iron core) as magnetic field generating means.
And is disposed and held inside the lower film guide 2a.

Reference numeral 2c denotes a horizontally long insulating intermediate plate, which is disposed so as to cover an upper opening of a lower film guide 2a in which an exciting coil 3 as a magnetic field generating means and a magnetic core 4 are disposed and supported inside. is there.

Reference numeral 6 denotes a horizontally long rigid body stay as a pressing member, which is disposed on the middle plate 2c.

Reference numeral 1 denotes a cylindrical or endless electromagnetic induction heating film. Hereinafter, it is referred to as a fixing film. The fixing film 1 has a substantially cylindrical film guide 2a.
-Loosely fitted to 2b.

7.7 are left and right annular flange members,
The lower and upper film guides 2a and 2b, which are formed into a substantially cylindrical body and are superimposed, are externally fitted to the left and right ends and fixed in position, and regulate and hold the ends of the fixing film 1. With the lower and upper film guides 2
a and 2b serve to keep the joined state by tightening.

Assembling of the lower film guide 2a, the excitation coil 3 and the magnetic core 4, the middle plate 2c, the stay 6, the upper film guide 2b, the fixing film 1, and the left and right annular flange members 7, 7 serving as magnetic field generating means. The body is the first member, which is conveniently referred to as the "heating assembly".

Reference numeral 5 denotes a pressing member as a second member. This example is an elastic pressure roller, which is composed of a core metal 5a and a heat-resistant elastic material layer 5b of silicone rubber, fluoro rubber, fluoro resin, or the like, which is formed and coated concentrically around the core in a roller shape. In the case of the apparatus of the present embodiment, the pressure roller 5 is arranged such that both ends of the metal core 5a are rotatably supported and held between the front and rear chassis side plates (not shown) of the apparatus. is there.

The heating assembly described above is disposed above the pressure roller 5 with the lower film guide 2a side facing downward, and the both ends of the stay 6 and the spring receiving members 8.8 on the device chassis side plate side are connected. The pressurizing springs 9 and 9 are contracted between them, thereby applying a pressing force to the stay 6. As a result, the magnetic core 4 and the lower film guide 2a are pressurized via the middle plate 2c, and the lower surface of the lower film guide 2a and the upper surface of the pressure roller 5 are pressed against each other with the fixing film 1 interposed therebetween so that the fixing nip portion is formed. N is formed.

The lower end surface of the magnetic core 4 is located at a position corresponding to the fixing nip N with the bottom plate of the lower film guide 2a interposed therebetween.

The pressing roller 5 is driven to rotate in the counterclockwise direction indicated by the arrow by the driving means M. A rotational force acts on the fixing film 1 by a frictional force between the pressing roller 5 and the outer surface of the fixing film 1 due to the rotational driving of the pressing roller 5, and the inner surface of the fixing film 1 moves downward at the fixing nip portion N. The lower and upper film guides, both of which form a substantially cylindrical body, with a peripheral speed substantially corresponding to the rotational peripheral speed of the pressure roller 5 in the clockwise direction shown by the arrow while sliding in close contact with the lower surface of the side film guide 2a. The outer circumference of 2a and 2b is rotated (pressure roller driving method).

In order to reduce the mutual sliding friction between the lower surface of the lower film guide 2a and the inner surface of the fixing film 1 in the fixing nip N, the lower surface of the lower film guide 2a of the fixing nip N and the fixing film 1 Lubricant such as heat-resistant grease is interposed between the inner surface.

An exciting circuit (not shown) is connected to the exciting coil 3. This excitation circuit is from 20 kHz to 500 kHz.
A high frequency of z can be generated by a switching power supply.

The exciting coil 3 generates an alternating magnetic flux by an alternating current (high-frequency current) supplied from the exciting circuit. The alternating magnetic flux is guided to the magnetic core 4 and is intensively distributed around the fixing nip N and its vicinity, and mainly generates an eddy current in the electromagnetic induction heating layer of the fixing film 1 at and around the fixing nip N. This eddy current generates Joule heat (eddy current loss) in the electromagnetic induction heating layer due to the specific resistance of the electromagnetic induction heating layer. That is, the fixing film 1 generates electromagnetic induction heat. The electromagnetic induction heat of the fixing film 1 is generated intensively in the fixing nip portion N where the alternating magnetic flux is intensively distributed and in the vicinity thereof, so that the fixing nip portion N is heated with high efficiency.

The temperature of the fixing nip N is controlled such that a predetermined temperature is maintained by controlling the current supply to the exciting coil 3 by a temperature control system including a temperature detecting means (not shown).

Thus, the pressure roller 5 is driven to rotate, and accordingly, the cylindrical fixing film 1 rotates around the lower and upper film guides 2a and 2b, and the pressure from the excitation circuit to the excitation coil 3 is increased. In the state where the fixing film 1 is electromagnetically heated by the power supply as described above and the fixing nip N rises to a predetermined temperature and the temperature is adjusted, the unfixed toner image t conveyed from the image forming unit is formed. The recording material P is introduced between the fixing film 1 in the fixing nip portion N and the pressure roller 5 with the image surface facing upward, that is, facing the fixing film surface. The fixing nip N is conveyed together with the fixing film 1 in close contact with the outer surface. In the process of nipping and transporting the recording material P along with the fixing film 1 through the fixing nip N, the unfixed toner image t on the recording material P is heated and fixed by the electromagnetic induction heating of the fixing film 1. You. When the recording material P passes through the fixing nip portion N, it is separated from the outer surface of the rotary fixing film 1 and is discharged and conveyed. After passing through the fixing nip, the heat-fixed toner image on the recording material is cooled and becomes a permanent fixed image.

B) Fixing Film 1 The cylindrical or endless fixing film 1 as a rotating body is of the type shown in FIG. 5, as shown in FIG. A heat-generating layer 1a made of a metal film or the like, an elastic layer 1b laminated on its outer surface, and a release layer 1c further laminated on its outer surface have a three-layer composite structure.

. The heat generating layer 1a is preferably made of a ferromagnetic metal such as nickel, iron, ferromagnetic SUS, nickel-cobalt alloy, and the like, and has a thickness of 1 to 100 μm in view of the electromagnetic energy absorption efficiency and the rigidity of the film. Is preferred.

[0071] The elastic layer 1b is a layer necessary for preventing unevenness in gloss of an image by fixing a heating surface (release layer 1c) to unevenness of a recording material or unevenness of a toner layer when fixing a color image or the like. Yes, a material having good heat resistance and good thermal conductivity such as silicone rubber, fluorine rubber, fluorosilicone rubber or the like is used.
° (JIS-A) or less.

[0072] The release layer 1c has a thickness of 1 to 100 μm.
Of fluororesin, silicone resin, fluorosilicone rubber, fluororubber, silicone rubber, PFA, PTFE,
A material having good releasability and heat resistance such as FEP is used.

Further, a fluorine resin is provided inside the heat generating layer 1a.
Polyimide resin, polyamide resin, PEEK resin, PE
S resin, PPS resin, PFA resin, PTFE resin, FE
A heat insulating layer 1d made of a heat-resistant resin such as a P resin may be provided to further increase the efficiency of supplying heat to the recording material P.

C) Film guide members 2a and 2b The film guides 2a and 2b are made of a phenol resin, a polyimide resin, a polyamide resin, a polyamide-imide resin, or a phenol resin for securing insulation between the exciting coil 3 and the fixing film 1.
EEK resin, PES resin, PPS resin, PFA resin, P
A material having good insulation and heat resistance, such as TFE resin and LCP resin, is used. Pressing of the press contact portion (nip portion N), support of the exciting coil 3 and magnetic core 4 as a magnetic field generating means, and fixing of the fixing film 1 are performed. It serves to support and improve the transport stability of the film 1 during rotation.

D) Excitation Coil 3 / Magnetic Core 4 The excitation coil 3 is formed by bundling a plurality of copper thin wires, each of which is individually insulated and coated, and winding the bundle a plurality of times to form a coil (wire loop). And is connected to an excitation circuit (not shown). In this example, polyimide is used as the heat-resistant insulating film and the number of turns is 12 (12 turns). The diameter of the thin wire and the cross-sectional area of the bundle are determined by the amount of current flowing through the exciting coil 3. In this example, 98 thin wires having a diameter of 0.2 mm are bundled (the cross-sectional area of the bundle is about 3.1 mm ² ). Is used.

The magnetic core 4 is a T-shaped high-permeability core having a T-shaped cross section, and is made of a material such as ferrite or permalloy used for the core of a transformer (more preferably 100%).
Ferrite with low loss even at kHz or higher is used.

The positional relationship between the excitation coil 3 and the magnetic core 4 with respect to the fixing film 1 is arranged in the film guide 2a so that the heat generation efficiency and the like are optimized. In particular, it is preferable to dispose the exciting coil 3 and the fixing film 1 as close as possible. In this example, the distance between the exciting coil 3 and the fixing film 1 is set to 0.5 mm. I have.

E) Measures for Lubricant Circulation FIG. 6A is a perspective view of one end of the film guide 2a with the lower film guide 2a facing upward, and FIG. 6B is a perspective view of a portion of the film guide 2a corresponding to the fixing nip portion N. It is an enlarged sectional model diagram. 7A is a partially enlarged plan view of a surface portion of the film guide 2a corresponding to the fixing nip portion N, and FIG. 7B is a view A of FIG.
It is sectional drawing which follows the -A 'line.

Reference numeral 10 denotes a plurality of circumferential ribs formed on the outer side surface of the film guide 2a at intervals along the length of the film guide, and is provided between the side surface of the fill guide 2a and the inner surface of the fixing film 1. It has the effect of reducing the contact sliding resistance and reducing the rotational load of the fixing film 1.

Reference numeral 11 denotes an S-shaped groove formed on the surface corresponding to the fixing nip portion N of the film guide 2a and having a width of 0.1 to 1.5 mm and a depth of 0.1 to 0.5 mm. It is formed at equal intervals along the longitudinal direction by cutting or the like so that the area is 5 to 50% of the area of the surface corresponding to the fixing nip portion N.

By providing the groove 11, an interposition is provided between the film guide 2a and the inner surface of the fixing film 1 in order to reduce the mutual sliding frictional force between the film guide 2a and the inner surface of the fixing film 1 in the fixing nip portion N. It is possible to stably circulate and supply the lubricated lubricant through durability.

That is, conventionally, the lubricant accumulates in the vicinity of the upstream side of the fixing nip between the fixing film 1 and the film guide 2a, and an appropriate amount of the lubricant circulates together with the fixing film by the rotation of the fixing film 1 and the space between the inner surface of the fixing film and the film guide 2a. , The mutual sliding frictional force at the fixing nip portion N is reduced. However, when the lubricant is deteriorated due to durability or the like, the circulation is deteriorated, and the rotational torque is increased.

In this embodiment, the lubricant does not accumulate in the vicinity of the fixing nip due to the rotation of the fixing film 1, but always remains in the groove 1.
1, the proper amount is provided between the inner surface of the fixing film and the film guide 2 a from the fixing nip portion and the groove 11, so that even when the lubricant is deteriorated due to durability or the like, the lubricant is stably provided on the inner surface of the film. And the film guide 2a. Therefore, torque increase due to durability can be prevented, and the drive roller (drive motor) loses synchronism,
It is possible to extend the life of the apparatus without causing trouble such as fixing jam.

The shape of the groove 11, the ratio of the total area of the groove 11 to the fixing nip N, and the like are appropriately determined by the pressing force, the materials of the fixing film and the film guide 2a, and the like.

Reference numeral 12 denotes a projection provided at the center in the width direction of the surface of the film guide 2a corresponding to the fixing nip portion N. The protrusion 12 is a rod-shaped protrusion having a semi-elliptical cross-sectional shape for local pressurization configured to be substantially parallel to the core of the pressure roller over the lengthwise direction on the pressure roller side. The protrusion 12 is formed by grinding the guide 2a or the like.
Has a height H1 of 0.1 to 1 mm and a width of 5 times the fixing nip width.
６０60%.

FIG. 8 shows that the fixing device of this embodiment has a total pressure of 2
FIG. 9 is a diagram illustrating a distribution of a pressing force at a fixing nip portion N when the pressure springs 9 adjusted to be 0 kgf are used. As a comparative example, a pressure distribution in a film guide 2a having no projection 12 at a portion corresponding to the fixing nip N is also shown.

As can be seen from FIG. 8, the protrusion 1 is smaller than the case where the protrusion 12 is not provided in the fixing nip N (Comparative Example).
2, the pressing force applied to the fixing nip N increases at the position of the protrusion 12, and the pressing force of the fixing nip other than the protrusion 12 decreases accordingly. Is almost the same as the case where no is provided.

Therefore, the projection 12 is provided at the portion corresponding to the fixing nip portion N of the film guide 2a.
A portion having a high pressing force can be locally formed without increasing the total pressing force of the entire fixing nip portion. In other words, since it is possible to prevent the increase of the rotational torque and sufficiently provide the pressing force necessary for ensuring the transparency and the fixing property, the fixing property can be improved, and even when the fixing process speed is increased, A good fixed image can be obtained.

The height H1 of the projection 12 is set to 0.1 m
When the height is less than m, the effect of increasing the local pressing force is reduced, and desired effects such as improvement in permeability cannot be obtained. On the other hand, when the height is more than 1 mm, fixing nip portion formation and local pressing are not performed. The increase in pressure cannot be achieved.

Further, when the width of the projection 12 is smaller than 5% of the width of the fixing nip, the effect of increasing the pressing force is reduced, and the desired effects such as improvement of the transmittance cannot be obtained. If the width of the roller 12 is larger than 60% of the width of the fixing nip, it is impossible to form the fixing nip and increase the local pressing force.

FIG. 9 shows, as a confirmation of the effect of the present embodiment, the rotation time (converted to the number of A4 paper sheets) when the fixing device 100 of the present embodiment is continuously rotated at a pressure of 20 kgf by an idle rotating machine. FIG. 7) is a diagram showing rotation torque.

As a comparative example, a case where a film guide 2a in which the projection 12 and the groove 11 are not provided on the surface portion corresponding to the fixing nip portion N is also shown.

As can be seen from the figure, in the comparative example, the initial torque was 4 kg · cm, but the torque was 750 hours (20 hours).
The torque suddenly increases around the time after rotation, and after 800 hours, the torque becomes 7.5 kg · cm or more, and the drive roller loses synchronism. In this case, the rotation torque hardly changes even after 1000 hours of rotation.

Further, when the fixing device 100 of the present embodiment is actually used in an image forming apparatus to fix an OHT image, the transparency is improved, and the process speed at the time of fixing the OHT is increased. However, sufficient transparency could be secured. Furthermore, even when a color image was fixed on thick paper or the like, the fixing property was improved, and sufficient fixing property could be secured even at high speed.

In this embodiment, the ribs 10, the grooves 11, and the projections 12 are formed by cutting or the like after forming the film guide 2a.
The same effect was obtained when a member formed integrally with a mold or the like at the time of molding a or a member attached later by bonding or the like was used.

<Embodiment 2> (FIG. 10) In this embodiment, as shown in FIG. 10 (a), a V-shaped projection 13 is formed on the surface of the film guide 2a corresponding to the fixing nip N in the paper advancing direction. It is provided.

FIG. 10A is a partially enlarged plan view of the surface of the film guide 2a corresponding to the fixing nip portion N, and FIG. 10B is a cross-sectional view taken along the line BB 'in FIG.

The V-shaped protrusion 13 restricts the deviation of the fixing film 1 due to the rotation, thereby stabilizing the paper conveyance.

Further, since the projection 13 is provided so as to be oblique with respect to the paper conveyance direction, the sudden pressure change over the entire length in the paper conveyance direction is relieved, and the torque change in the paper conveyance direction is reduced. It can be made smaller and the paper transport is stabilized.

Similarly, in this embodiment, since a portion having a high pressing force can be locally formed without increasing the total pressing force of the entire fixing nip portion, it is possible to prevent the rotation torque from increasing and to improve the transmission and the transmission. It is possible to provide the pressing force necessary for securing the fixing property, and it is possible to obtain a good fixed image even when the fixing process speed is increased. Further, the provision of the groove 11 allows the lubricant to be circulated satisfactorily throughout the durability, thereby preventing an increase in torque and extending the life.

<Embodiment 3> (FIGS. 11 and 12) FIG. 11A shows a fixing device 100 according to the present embodiment.
Fig. 12 (a) shows a film guide 2a.
A partially enlarged plan view of a surface portion corresponding to the fixing nip portion N of FIG.
(B) is a sectional view taken along the line AA 'of (a), and (c) is a sectional view taken along the line BB' of (a).

This embodiment is different from the first embodiment in that, instead of the coil 3 and the core 4 as the magnetic field generating means, the cross-sectional shape is E
The C-shaped coil / core unit 14 is used as a magnetic field generating means, and two protrusions 15.
15 is provided.

The E-shaped coil / core unit 14 of this example
Has two heat generation peaks within the width of the fixing nip N as shown in FIG. 11B, and the protrusions 15 are provided at the positions of the heat generation peaks. The height H2 of the projections 15, 15 is 0.4 to 1 mm, and the width is half of the width of the projection 12 in the first embodiment.
It is configured to be 60%.

With this configuration, it is possible to locally form a portion having a high pressing force without increasing the total pressing force of the entire fixing nip portion. The pressure required for ensuring the fixing property and the fixing property can be provided, and a good fixed image can be obtained even when the fixing process speed is increased.

Further, since the two projections 15 are provided in accordance with the two heat generation peaks, efficient heating and pressurization can be performed, and a portion to which the pressure is locally increased can be applied. The opportunity of contact with the recording material increases, and more reliable pressurization and heating can be performed.

In the case of a heating device having a plurality of heat generation peaks in the fixing nip, a similar effect can be obtained by providing a plurality of protrusions in accordance with the heat generation peak. In this example, the groove 11 and the protrusions 15.
5 is provided, especially when the torque increase due to durability is small, a configuration may be adopted in which only the protrusions 15 are provided and the groove 11 is omitted. For example, when only the groove 11 is provided, only the groove 11 may be provided, and the protrusions 15 may be omitted. Both the groove 11 and the protrusions 15 may not be provided at the same time.

Embodiment 4 (FIGS. 13 to 17) This embodiment is an example of a film heating type fixing device using a ceramic heater as a heating element.

FIG. 13 is a front view of the apparatus 100 with the middle part omitted, FIG. 14 is a longitudinal sectional view with the middle part omitted, and FIG.
5 is a cross-sectional model diagram.

Reference numeral 18 denotes a heat-resistant and heat-insulating film guide having a substantially semi-circular cross section in a cross section, and reference numeral 17 denotes a ceramic heater as a heating element, which is formed substantially in the center of the lower surface of the film guide 18 along the guide length. It is fitted and fixedly supported in the groove provided.

Reference numeral 16 denotes a cylindrical or endless heat-resistant fixing film. The fixing film 16 is loosely fitted on a film guide 18.

Reference numeral 25 denotes an annular flange member which is fitted to one end of the film guide 18 and serves as a film shift control means.

Reference numeral 20 denotes a rigid stay for pressure inserted inside the film guide 18.

The above film guide 18, ceramic heater 17, fixing film 16, annular flange member 25,
The assembly of the pressurizing rigid stay 20 is a first member, which is referred to as a “heating assembly” for convenience.

Reference numeral 19 denotes a pressing member as a second member.
This example is an elastic pressure roller, in which the hardness is reduced by providing an elastic layer 19b of silicone rubber or the like on a core metal 19a. Both ends of the core metal 19a are connected to chassis (not shown) of the front and rear chassis (not shown) of the apparatus. The bearings are rotatably held between the side plates. To further improve the surface properties, PTF
A fluororesin layer such as E, PFA, or FEP may be provided.

On the upper side of the pressure roller 19, the above-mentioned heating assembly is disposed with the lower surface of the film guide 18 facing downward, and the both ends of the stay 20 and the spring receiving members 21 on the apparatus chassis side plate side are connected. Pressure spring 2 between each
The stays 20 are pressed down by the contraction of the pins 2 and 22. As a result, the film guide 18 is pressed and the lower surface of the ceramic heater 17 disposed on the lower surface of the film guide 18 and the pressing roller 19 are fixed to the fixing film 16.
The fixing nip portion N is formed by pressing the fixing nip therebetween.

The pressing roller 19 is driven by the driving means M to rotate in the counterclockwise direction shown by the arrow. The rotational force acts on the fixing film 16 by the frictional force between the pressing roller 19 and the outer surface of the fixing film 16 due to the rotational drive of the pressing roller 19,
The fixing film 16 slides in the fixing nip portion N in close contact with the lower surface of the ceramic heater 17 in a clockwise direction indicated by an arrow at a peripheral speed substantially corresponding to the rotational peripheral speed of the pressure roller 19. Is turned around (the pressure roller driving method).

In order to reduce the mutual sliding friction force between the lower surface of the ceramic heater 17 and the inner surface of the fixing film 16 in the fixing nip N, the lower surface of the ceramic heater 17 in the fixing nip N and the inner surface of the fixing film 16 are reduced. A lubricant such as heat-resistant grease is interposed in the oil.

The rotation of the pressure roller 19 is started based on the print start signal, and the heating of the ceramic heater 17 is started. When the rotation peripheral speed of the fixing film 16 due to the rotation of the pressure roller 19 is stabilized and the temperature of the ceramic heater 17 rises to a predetermined value, the fixing film 16 in the fixing nip N and the pressure roller 1
9, a recording material P carrying a toner image t as a material to be heated is introduced with the toner image carrying surface side toward the fixing film 16 so that the recording material P is fixed at the fixing nip N
In the ceramic heater 1 via the fixing film 16
7, the fixing nip N is fixed to the lower surface of the fixing film 16.
And move along with it. In the moving passage process, the heat of the ceramic heater 17 is applied to the recording material P via the fixing film 16 and the toner image t is heated and fixed on the surface of the recording material P. Recording material P that has passed through fixing nip portion N
Is transported separately from the surface of the fixing film 16.

The fixing film 16 has a film thickness of 100 μm or less, preferably 50 μm or less and preferably 20 μm or more and has a single layer of heat-resistant PTFE, PFA, FEP, or polyimide, in order to reduce the heat capacity and improve the quick start property. Polyimide amide, PEEK, PES, P
A composite layer film in which the outer peripheral surface of PS or the like is coated with PTFE, PFA, FEP, or the like can be used. In this example, a polyimide film having a diameter of 20 mm with the outer peripheral surface coated with PTFE was used.

A ceramic heater 17 as a heating element is
This is a low-heat-capacity horizontally long linear heating element whose longitudinal direction is the direction perpendicular to the moving direction of the fixing film 16 and the recording material P. FIG. 16 is a schematic cross-sectional view of the ceramic heater 17.
A heater substrate 17a made of alumina or the like, and a heating layer 17 provided on the surface of the heater substrate 17a along its length.
b, a heating layer 17b formed by applying an electric resistance material such as Ag / Pd (silver / palladium) to a thickness of about 10 μm and a width of 1 to 5 mm by screen printing or the like, and a glass or fluororesin further provided thereon And the like, as a basic configuration.

When electricity is supplied between both ends of the heat generating layer 17b of the ceramic heater 17, the heat generating layer 17b generates heat and the temperature of the heater 17 rises rapidly. The heater temperature is detected by a temperature sensor (not shown), and the power supply to the heat generating layer 17b is controlled by a control circuit (not shown) so that the heater temperature is maintained at a predetermined temperature, and the temperature of the heater 17 is controlled.

The ceramic heater 17 is fixedly supported by being fitted into a groove formed substantially at the center of the lower surface of the film guide 18 along the length of the guide with the protective layer 17c side exposed downward. Therefore, in the fixing nip portion N, the surface of the protective layer 17c of the ceramic heater 17 and the inner surface of the fixing film 1 slide in contact with each other.

FIG. 17A is a partially enlarged plan view of the ceramic heater 17 on the protective layer 17c side, FIG. 17B is a cross-sectional view taken along the line AA ′ of FIG. 17A, and FIG. It is sectional drawing in alignment with the BB 'line of FIG.

The protective layer 17c of the ceramic heater 17 is
In addition to the protection of the heat generating layer 17b, the fixing nip forming portion with the pressure roller 19 serves as a film guide, and the surface of the protective layer 17c is provided with a lubricant so as to be oblique to the rotation direction of the fixing film 16. Groove for circulation 23
, A projection 24 for local pressurization is formed.

In this example, the groove 23 has a width of 0.5 mm and a depth of 0.2 mm at intervals of 2 mm, and the protrusion 24 has a height H.
3 is 0.8 mm and width is 0.5 mm (fixing nip width 5 m
(10% of m).

With such a configuration, the provision of the groove 23 for circulating the lubricant enables the lubricant to be circulated and supplied stably through the durability, so that the torque increase due to the durability can be prevented, and the drive roller It is possible to extend the life of the apparatus without occurrence of a step-out or a trouble such as fixing jam. Further, the provision of the projections 24 makes it possible to locally form a portion having a high pressing force without increasing the total pressing force of the entire fixing nip portion. It can provide the necessary pressure for securing. Therefore, even when the fixing process speed is increased, a good fixed image can be obtained.

Further, by disposing the projections 24 at an angle to the paper transporting direction, a force acts on the fixing film 16 so as to move in one longitudinal direction by rotation, so that
The moving direction of the fixing film 16 along the length of the film guide 18 can be specified in one direction, and therefore, the specified moving direction a of the fixing film 16 (FIG. 1)
By providing the annular flange member 25 as the film shift movement restricting means only on the end side of the film guide 4), it is possible to easily control the shift movement of the fixing film at low cost.

Similarly, by arranging the groove 23 obliquely to the paper transport direction, the fixing film 16 can be moved in one direction in the longitudinal direction of the film guide 18 by the rotation of the fixing film 16. Since a force acts, an annular flange member 25 is provided on the end side of the film guide in the specified direction of movement of the fixing film to restrict the movement of the fixing film at a low cost. It becomes possible to control.

<Embodiment 5> (FIGS. 18 to 21) FIG. 18 is a schematic cross-sectional view of a main part of a film heating type fixing device according to the present embodiment. The fixing device of this example is
As in the case of the first embodiment, the apparatus is of a pressure roller driving type / electromagnetic induction heating type using a cylindrical electromagnetic induction heating film 1. Constituent members and portions common to the device of the first embodiment are denoted by common reference numerals, and description thereof will not be repeated.

FIG. 19 is a perspective model diagram in which the lower surface of the lower film guide 2a faces upward. 10 is the first embodiment.
Of the film guide 2a,
A plurality of circumferential ribs formed on the outer side surface at intervals along the length of the film guide to reduce the contact sliding resistance between the side surface of the film guide 2a and the inner surface of the fixing film 1. It acts to reduce the rotational load of the fixing film 1.

The surface of the lower surface of the film guide 2a corresponding to the fixing nip portion N has a concave shape N 'in which the shape of the long nip surface is smaller than the outer diameter of the pressure roller.
, The pressing force is locally increased at both ends in the width direction of the fixing nip portion N.

FIG. 21 is a cross-sectional view in the width direction of the fixing nip portion N. The height H4 of the fixing nip N at both ends in the width direction from the parallel surface is formed to be 0.1 to 1 mm by adjusting the width of the fixing nip N and the concave shape N ′.

Reference numeral 28 denotes a part provided on the lower surface N 'of the film guide 2a from the upstream side in the fixing film rotation direction of the fixing nip N to the center of the fixing nip N, the width being 0.5 mm. , A groove having a depth of 0.2 mm, which is arranged at intervals of 2 mm in the longitudinal direction of the concave portion N '. FIG. 20 is an enlarged perspective model view of a portion where the groove 28 is formed.

By adopting such a structure, it is possible to locally form a portion having a high pressing force without increasing the total pressing force of the entire fixing nip portion. It is possible to provide the pressing force necessary for securing the fixing property, and it is possible to obtain a good fixed image even when the fixing process speed is increased.

Further, it is possible to prevent an increase in torque due to durability, and it is possible to prolong the life of the apparatus without occurrence of problems such as step-out of the driving roller and fixing jam.

That is, by using the concave fixing nip surface having a diameter smaller than the outer diameter of the pressure roller, the pressing force is increased at both ends of the fixing nip portion N in the rotation direction of the fixing film, and the fixing film of the fixing nip portion N is increased. Since the pressing force at the central portion in the rotation direction is small, it is possible to prevent the total pressing force from increasing, and to locally increase the pressing force. Further, the pressing force at the central portion in the width direction of the fixing nip portion is small, and the groove 28 provided up to the central portion in the width direction of the fixing nip portion.
Thereby, the lubricant easily accumulates in the central portion in the width direction of the fixing nip portion, and by rotation of the fixing film, an appropriate amount is supplied from the upstream portion, the central portion, and the groove 28 of the fixing nip portion. The lubricant can be supplied stably.

<Embodiment 6> (FIG. 22) This embodiment is another example of the configuration of a film heating type heating device.

In the apparatus shown in FIG. 22A, the fixing film 1 of electromagnetic induction heat is driven by being stretched and supported between a driving roller 31, a tension roller 32, and a film guide 2. The device is configured to be driven to rotate by the rotation of the roller 31.

The device (b) employs a pressure roller drive system. The fixing film uses a heat-resistant film 16 having no electromagnetic induction heat generation, and an electromagnetic induction heat generation member 1A such as an iron plate is provided on the lower surface of a film guide 18. The magnetic field generating means including the exciting coil 3 and the core 4 is disposed inside the film guide 18, and the fixed electromagnetic induction heating member 1A is caused to generate heat by the magnetic field generating means. The apparatus has a configuration in which heat is applied to the recording material P introduced into the fixing nip N via the heat-resistant film 16.

The present invention is also effective when applied to such a belt heating type heating device.

<Other Embodiments> 1) In the above embodiment, the pressing roller 5 as the second member is used.
Alternatively, 19 is fixedly disposed, and a heating assembly as a first member is provided with a pressure spring 9 as an urging member.
9 or 22 ・ 22 and the stay 6 or 20 as a pressing force holding member are pressed to form a nip portion N between them. On the contrary, the position of the stay 6 or 20 is fixed and pressure is applied to the heating assembly side. The roller 5 or 19 may be pressed by an urging member to form the nip portion N, or both the heating assembly side and the pressing roller side may be mutually pressed by the urging member to form the nip portion N. Is also good.

2) The image forming apparatus of the embodiment is a four-color image forming apparatus, but may be a monochrome or one-pulse multi-color image forming apparatus. 1 may be a form in which the elastic layer 1b is omitted. The heat generating layer 1a may be formed by mixing a metal filler into a resin.

Further, the fixing film 1 having an electromagnetic induction heating property is
An arbitrary layer configuration such as a two-layer configuration of the heat generation layer 1a and the release layer 1c, a three-layer configuration of the heat insulation layer 1d, the heat generation layer 1a, and the release layer 1c, and a single layer of the heat generation layer 1a can be used.

3) The image forming principle and system of the image forming apparatus is not limited to the electrophotographic process, but may be any other system such as a transfer system or a direct system electrostatic recording process and a magnetic recording process.

4) The pressing member 5 or 19 is not limited to the roller body, but may be another type of member such as a rotating belt type.

In order to supply thermal energy to the recording material also from the pressing member 5 or 19 side, a heating means such as an electromagnetic induction heating or a halogen heater is provided on the pressing member side to heat the recording material to a predetermined temperature. An apparatus configuration for controlling the temperature can also be used.

5) The heating device of the present invention is not limited to the image heating and fixing device of the embodiment, but may be an image heating device for heating a recording material carrying an image to improve the surface properties such as gloss. Image heating equipment, other heating and drying equipment for heated materials,
It can be widely used as a means / apparatus for heat-treating a material to be heated, such as a heating lamination apparatus.

[0148]

As described above, according to the present invention,
By providing a groove in the part where the nip is formed with the pressing member through the film, it is possible to circulate the lubricant well and prevent the rotation torque from increasing due to durability, and to extend the life of the device. In addition, it is possible to provide an apparatus that does not cause a problem such as step-out of the drive roller or fixing jam.

Further, by providing a projection at the portion where the nip is formed with the pressing member via the film, it is possible to locally form a portion having a high pressing force without increasing the total pressing force at the nip portion. Even when fixing a medium that requires transparency or fixing a high-gloss medium, it is possible to improve the fixing property and increase the speed of the apparatus while maintaining good fixing property. It becomes possible.

[Brief description of the drawings]

FIG. 1 is a schematic configuration diagram of an example of an image forming apparatus according to a first embodiment.

FIG. 2 is a schematic front view of the fixing device with an intermediate portion omitted.

FIG. 3 is a longitudinal cross-sectional model view of the same device with an intermediate portion omitted.

FIG. 4 is a schematic cross-sectional view of the apparatus.

FIG. 5 is a schematic diagram of a layer structure of a fixing film having electromagnetic induction heat generation.

FIG. 6A is a perspective model view of one end portion with a lower film guide facing upward, and FIG. 6B is an enlarged cross-sectional model view of a portion corresponding to a fixing nip portion of the film guide.

7A is a partially enlarged plan view of a portion corresponding to a fixing nip portion of a film guide, and FIG. 7B is a cross-sectional view taken along line AA ′ of FIG.

FIG. 8 is a distribution diagram of a pressing force at a fixing nip portion.

FIG. 9 is a diagram showing a change in torque due to rotation of a fixing film.

FIG. 10A is a partially enlarged plan view of a surface portion corresponding to a fixing nip portion of a film guide according to a second embodiment;
(B) is a sectional view taken along line BB 'of (a).

11A is a schematic cross-sectional view of the apparatus according to the third embodiment, and FIG. 11B is a calorific value distribution diagram in a fixing nip portion width direction.

12A is a partially enlarged plan view of a surface corresponding to a fixing nip portion of a film guide in the same apparatus, FIG. 12B is a cross-sectional view taken along line AA ′ of FIG. 12A, and FIG. a) B
Sectional view along -B 'line

FIG. 13 is a front model diagram of the device of Embodiment 4 with the intermediate part omitted.

FIG. 14 is a vertical cross-sectional model view of the same device with an intermediate portion omitted.

FIG. 15 is a schematic cross-sectional view of the same device.

FIG. 16 is a schematic cross-sectional view of a ceramic heater as a heating element.

17A is a partially enlarged plan view of the ceramic heater on the protective layer side, FIG. 17B is a cross-sectional view taken along line AA ′ of FIG. 17A, and FIG. Sectional view along line B '

FIG. 18 is a schematic cross-sectional view of a main part of the device according to the fifth embodiment.

FIG. 19 is a perspective model view in which the lower surface side of a lower film guide in the apparatus is directed upward.

FIG. 20 is an enlarged perspective model view of a groove forming portion of a lower film guide.

FIG. 21 is a cross-sectional view in the width direction of a fixing nip portion.

FIGS. 22A and 22B are schematic diagrams each showing another example of a configuration of a heating device of a film heating system.

[Explanation of symbols]

 1.16 Fixing Film 2a, 2b, 2 Film Guide 3 Excitation Coil 4 Magnetic Core 5.19 Pressure Roller 6.20 Pressing Stay 7.25 Fixing Film Deviation Movement Limiting Member N Fixing Nip 11 Grooves 12.15 Projection

Claims (14)

[Claims] A rotating member, a pressing member for pressing the rotating member,
And a supporting member that supports the rotating body, and a heating device that presses and heats the heated material by nipping and conveying the heated material at a contact portion formed by abutting the rotating body and the pressing member. A heating device, characterized in that a groove is provided in a portion of a support member that supports the rotating body, the portion corresponding to a contact portion formed by the contact between the rotating body and the pressing member. 2. The heating device according to claim 1, wherein the groove is formed so as to occupy 5 to 50% of an area of a contact portion formed by contact between the rotating body and the pressing member. apparatus. 3. The heating device according to claim 1, wherein the groove has a width of 0.1 to 1.5 mm and a depth of 0.1 to 0.5 mm. 4. The heating device according to claim 1, wherein the grooves are arranged obliquely with respect to a traveling direction of a material to be heated. 5. A rotating body, a pressing member for pressing the rotating body,
And a supporting member that supports the rotating body, and a heating device that pressurizes and heats the heated material by nipping and transporting the heated material at a contact portion formed by contact between the rotating body and the pressing member. A heating device, wherein at least one or more projections are provided on a portion of a support member that supports the rotating body, which corresponds to a contact portion formed by abutment between the rotating body and the pressing member. 6. A height of the projection from a contact surface formed by contact between the rotating body and the pressing member is 0.1 mm.
The heating device according to claim 5, wherein the width is 5 to 60% of the width of the contact surface. 7. The heating device according to claim 5, wherein the protrusions are arranged obliquely with respect to a traveling direction of the material to be heated. 8. A rotating body, a pressing member for pressing the rotating body,
And a supporting member that supports the rotating body, and a heating device that pressurizes and heats the heated material by nipping and transporting the heated material at a contact portion formed by contact between the rotating body and the pressing member. The shape of a portion corresponding to a contact portion formed by the contact between the rotating member and the pressing member of the supporting member for supporting the rotating member,
A heating device characterized in that the pressure is locally increased. 9. A rotating body, a pressing member for pressing the rotating body,
And a supporting member that supports the rotating body, and a heating device that pressurizes and heats the heated material by nipping and transporting the heated material at a contact portion formed by contact between the rotating body and the pressing member. The shape of a portion corresponding to a contact portion formed by the contact between the rotating member and the pressing member of the supporting member for supporting the rotating member,
A heating device formed so as to have a concave shape having a diameter smaller than the outer diameter of the pressing member. 10. An electromagnetic induction heating member, a first member having a magnetic field generating means for generating a magnetic field by applying a magnetic field to the electromagnetic induction heating member, and mutually press-contacting the first member directly or with another member interposed therebetween. A second member that forms a nip portion by heating, and applies heat energy to the heated material introduced into the nip portion and nipped and conveyed by heat generated by the electromagnetic induction heating member to heat the heated material. 10. The heating device according to any one of 9 above. 11. A heat-resistant film is brought into close contact with a heating member with a pressing member and slid and rotated, and a material to be heated is placed in a press-contact nip portion formed by the heating member and the pressing member with the heat-resistant film interposed therebetween. The heating device according to any one of claims 1 to 9, wherein the heating member is introduced, and heat of the heating member is applied to the member to be heated via the heat-resistant film to heat the material to be heated. 12. The apparatus according to claim 1, wherein the material to be heated is a recording material on which an unfixed image is formed and carried, and the apparatus is a heat fixing device for heating and fixing the unfixed image on the recording material. 12. The heating device according to any one of 11 above. 13. An image forming means for forming and carrying an unfixed image on a recording material, and a fixing means for fixing the unfixed image formed and carried on the recording material, wherein the fixing means is provided. An image forming apparatus, which is the heating apparatus according to any one of the above. 14. An image carrier as a member to be charged, charging means for charging said image carrier, exposure means for exposing said image carrier to form an electrostatic latent image, and said electrostatic latent image Developing means for forming a toner image by adhering toner to the toner, transferring means for transferring the toner image on the image carrier to a transfer material, and fixing means for making the toner image transferred to the transfer material a permanent fixed image. An image forming apparatus comprising: the heating device according to claim 1.