JP2001142330A - Fixing device - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a fixing device where excessive press contact to a translucent substrate utilizing a glass member or translucent resin member is prevented, damage to the translucent substrate is prevented and where occurrence of fire due to damage to a heat ray radiating means when the translucent substrate is damaged by excessive press contact is prevented. SOLUTION: In the fixing device, the heat ray radiating means generating heat ray is provided inside, a roll-shaped rotating member for fixing by heat ray is formed with a cylindrical translucent substrate with translucency for the heat ray and a heat ray absorbing layer where the heat ray is absorbed outside the translucent substrate, the translucent substrate is covered to form a conductive path and it is characteristic of the device that feeding of power to the heat ray radiating means is stopped by a non-conduction of the conductive path.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a fixing device used for an image forming apparatus such as a copying machine, a printer, a facsimile, etc., and more particularly to a fixing device capable of quick start.

[0002]

2. Description of the Related Art Conventionally, as a fixing device used in an image forming apparatus such as a copying machine, a printer, a facsimile, etc., a heat roller fixing method has been used as a fixing device having high technical perfection and stability. Machine to full-color machine,
Has been widely adopted.

However, the conventional heat roller fixing type fixing device is disadvantageous in terms of energy saving because it is necessary to heat a fixing heat roller having a large heat capacity when heating a transfer material or toner. There is a problem that it takes time to warm up the fixing device during printing, and the printing time (warming-up time) becomes longer.

In order to solve this, a film (heat fixing film) is used, the heat roller is brought to the ultimate thickness of the heat fixing film to reduce the heat capacity, and a temperature-controlled heater (ceramic heater) is directly applied to the heat fixing film. A film fixing type fixing device and an image forming device using the same have been proposed, which greatly improve the heat conduction efficiency by being brought into contact with the pressure and achieve a quick start that saves energy and requires almost no warm-up time. Have been

Further, as a modification of the heat roller, a transparent substrate is used as a heat ray fixing roller (rotating member for heat ray fixing), and the toner is heated and fixed by irradiating the toner with heat rays from a halogen lamp (heat ray irradiation means) provided inside. A fixing method which does not require a warm-up time and achieves a quick start is disclosed in JP-A-52-106741, JP-A-57-82240, JP-A-57-102736, and JP-A-57-10274.
No. 1 and the like. Further, a light absorbing layer (heat ray absorbing layer) is provided on the outer peripheral surface of the light transmitting substrate to constitute a heat ray fixing roller (rotating member for heat ray fixing), and a halogen lamp (heat ray) provided inside the cylindrical light transmitting substrate. JP-A-59-65867 discloses a fixing method in which light from the irradiating means is absorbed by a light-absorbing layer provided on the outer peripheral surface of a light-transmitting substrate, and a toner image is fixed by heat of the light-absorbing layer. ing.

[0006]

The above-mentioned JP-A-52-10
The fixing device disclosed in Japanese Patent No. 6741 or the like discloses a method of irradiating a heat ray from a halogen lamp (heat ray irradiating means) through a translucent substrate to heat and fix the toner, and a method disclosed in JP-A-59-65867. In the fixing device,
A light absorbing layer (heat ray absorbing layer) is provided on the outer peripheral surface of the light transmitting substrate to constitute a heat ray fixing roller (rotating member for heat ray fixing), and heat rays from a halogen lamp (heat ray irradiating means) are passed through the light transmitting substrate. The method of irradiating the absorbing layer and fixing the toner by the heat of the heat ray absorbing layer aims at energy saving and a quick start in which the warm-up time is shortened. Since a glass member or a translucent resin member or the like is used as the conductive base, when the pressurization is excessive during the pressurization with the pressurizing roller provided opposite to the heat ray fixing rotating member, the translucent base is Destroyed or destroyed translucent substrate destroys heat ray irradiating means using a halogen lamp or a xenon lamp provided inside the translucent substrate, causing a fire. Problem or will occur.

SUMMARY OF THE INVENTION The present invention solves the above-mentioned problems, prevents excessive pressure bonding to a light-transmitting substrate using a glass member or a light-transmitting resin member, prevents breakage of the light-transmitting substrate, and prevents excessive destruction of the light-transmitting substrate. It is an object of the present invention to provide a fixing device that prevents a fire caused by destruction of a heat ray irradiating means when a light-transmitting substrate is destroyed by pressure bonding.

[0008]

An object of the present invention is to provide a fixing device for fixing a toner image on a transfer material to the transfer material by heating and pressurizing, wherein the fixing device has a heat ray irradiating means for emitting heat rays therein. A cylindrical light-transmitting substrate having a light-transmitting property, and a heat-ray absorbing layer for absorbing the heat rays provided outside the light-transmitting substrate to form a roll-shaped rotating member for fixing a heat ray, A fixing device (1st invention), wherein a conductive path is formed by covering the translucent substrate, and power supply to the heat ray irradiating means is stopped when the conductive path is in a non-conductive state.
Achieved by

Another object of the present invention is to provide a fixing device for fixing a toner image on a transfer material to the transfer material by heating and pressurizing, wherein the fixing device has a heat ray irradiating means for emitting heat rays therein, and is transparent to the heat rays. A light-transmitting cylindrical light-transmitting substrate, and a heat-ray absorbing layer that absorbs the heat rays provided outside of the light-transmitting substrate to form a roll-shaped heat ray fixing rotating member,
A fixing device that transmits light in the axial direction of the light-transmitting substrate and stops power supply to the heat ray irradiating means due to a change in transmittance or reflectance of the transmitted light (second invention)
Achieved by

Another object of the present invention is to provide a fixing device for fixing a toner image on a transfer material to the transfer material by heating and pressurizing, wherein the fixing device has a heat ray irradiating means for emitting heat rays therein, and is transparent to the heat rays. A light-transmitting cylindrical light-transmitting substrate, and a heat-ray absorbing layer that absorbs the heat rays provided outside of the light-transmitting substrate to form a roll-shaped heat ray fixing rotating member,
A fixing device, wherein a pressure roller is provided to face the rotating member for heat ray fixing, and a proximity preventing member is provided on one of the rotating member for heat ray fixing or the pressure roller. ).

The above object is also achieved by a fixing device for fixing a toner image on a transfer material to the transfer material by heating and pressurizing, wherein the fixing device has a heat ray irradiating means for emitting heat rays therein, and is transparent to the heat rays. A light-transmitting cylindrical light-transmitting substrate, and a heat-ray absorbing layer that absorbs the heat rays provided outside of the light-transmitting substrate to form a roll-shaped heat ray fixing rotating member,
A pressing roller that forms a nip portion facing the rotating member for hot-wire fixing is provided, and one of the rotating member for hot-wire fixing or the pressing roller is provided with the rotating member for hot-wire fixing and the pressing roller. A pressure release means for performing pressure bonding and pressure release, and a switch means provided on one of the hot-wire fixing rotary member and the pressure roller, and the hot-wire fixing rotary member or the pressure roller by the pressure release means. When the movement exceeds a predetermined movement amount, the switch means is mechanically operated by the movement of the rotating member for heat ray fixing or the pressing roller, and the power supply to the heat ray irradiation means is stopped. This is achieved by a device (a fourth invention).

The above object is also achieved by a fixing device for fixing a toner image on a transfer material to the transfer material by heating and pressurizing, wherein the fixing device has a heat ray irradiating means for emitting heat rays therein, and is transparent to the heat rays. A light-transmitting cylindrical light-transmitting substrate, and a heat-ray absorbing layer that absorbs the heat rays provided outside of the light-transmitting substrate to form a roll-shaped heat ray fixing rotating member,
A pressure roller is provided so as to face the heat ray fixing rotating member. At least one of the heat ray fixing rotating member and the pressure roller is provided with a position detecting means, and the heat ray is detected by the position detecting means. The present invention is attained by a fixing device (fifth invention) characterized in that power supply to an irradiation unit is stopped or pressure contact between the heat ray fixing rotating member and the pressure roller is released.

[0013]

Embodiments of the present invention will be described below. Note that the description in this column does not limit the technical scope of the claims and the meaning of terms. Further, the following assertive description in the embodiment of the present invention indicates the best mode, and does not limit the meaning or technical scope of the terms of the present invention.

An image forming process and each mechanism of an embodiment of an image forming apparatus using a fixing device according to the present invention will be described with reference to FIGS. FIG. 1 is a cross-sectional configuration view of a color image forming apparatus showing an embodiment of an image forming apparatus using a fixing device according to the present invention, and FIG. 2 is a side cross-sectional view of the image forming body of FIG. FIG. 3 is an explanatory view showing the structure of the fixing device. FIG. 4 is an enlarged cross-sectional configuration diagram of the roll-shaped hot-wire fixing rotating member of FIG.
FIG. 6 is a diagram showing a concentration distribution of a heat ray absorbing layer of the roll-shaped heat ray fixing rotating member of FIG. 3; FIG. It is a figure which shows a thickness.

According to FIG. 1 or FIG. 2, a photosensitive drum 10, which is an image forming body, is provided on the outer periphery of a cylindrical base formed of a light-transmitting member such as glass or light-transmitting acrylic resin. It is formed by forming a photoconductive layer and a photoconductor layer of an organic photosensitive layer (OPC).

The photosensitive drum 10 is rotated clockwise as indicated by an arrow in FIG. 1 with the light-transmitting conductive layer grounded by power from a drive source (not shown).

In the present invention, the exposure beam for image exposure is
The photoconductor layer of the photoconductor drum 10, which is the image forming point, only needs to have an exposure light amount of a wavelength that can provide an appropriate contrast with respect to the light attenuation characteristic (photocarrier generation) of the photoconductor layer. . Therefore, the light transmittance of the light-transmitting substrate of the photosensitive drum in the present embodiment does not need to be 100%, and may have a characteristic of absorbing a certain amount of light when transmitting the exposure beam. . The point is that any suitable contrast can be provided. As a material of the light-transmitting substrate, an acrylic resin, particularly one obtained by polymerizing a methyl methacrylate monomer, is preferably used because of its excellent light-transmitting properties, strength, accuracy, surface properties, etc. Various translucent resins such as acryl, fluorine, polyester, polycarbonate, polyethylene terephthalate and the like used for the above can be used. Further, as long as it has a light-transmitting property with respect to the exposure light, it may be colored. As the light-transmitting conductive layer, indium tin oxide (I
TO), tin oxide, lead oxide, indium oxide, copper iodide, or a metal thin film of Au, Ag, Ni, Al, or the like that maintains light transmissivity. Reactive deposition method, various sputtering methods, various CV
D method, dip coating method, spray coating method and the like can be used.
Various organic photosensitive layers (OPC) can be used as the photoconductor layer.

The organic photosensitive layer serving as a photosensitive layer of the photoconductor layer includes a charge generation layer (CGL) mainly composed of a charge generation substance (CGM) and a charge transport layer (CTM) mainly composed of a charge transport substance (CTM). And CTL). An organic photosensitive layer having a two-layer structure has high durability as an organic photosensitive layer due to its thick CTL and is suitable for the present invention.
The organic photosensitive layer may have a single layer structure containing a charge generation material (CGM) and a charge transport material (CTM) in one layer. ,
Usually, a binder resin is contained.

A scorotron charger 11 as a charging unit described below and an exposure optical system 1 as an image writing unit
2. The developing device 13 as a developing unit is prepared for an image forming process for each color of yellow (Y), magenta (M), cyan (C) and black (K), respectively. Are arranged in the order of Y, M, C, and K with respect to the rotation direction of the photosensitive drum 10 indicated by the arrow in FIG.

Scorotron charger 11 as charging means
Is mounted so as to face and be close to the photosensitive drum 10 in a direction perpendicular to the moving direction of the photosensitive drum 10 as an image forming body (the direction perpendicular to the plane of FIG. 1). A control grid (no symbol) maintained at a predetermined potential with respect to the body layer;
As a, for example, a sawtooth electrode is used, and a charging action (in this embodiment, negative charging) is performed by corona discharge having the same polarity as that of the toner, thereby giving a uniform potential to the photosensitive drum 10. As the corona discharge electrode 11a, a wire electrode or a needle electrode may be used.

The exposure optical system 12 for each color is a linear exposure element (LED) in which a plurality of LEDs (light emitting diodes) as light emitting elements of image exposure light are arranged in an array parallel to the axis of the photosensitive drum 10. (Not shown) and a selfoc lens (not shown) as an equal-magnification imaging element are configured as an exposure unit attached to a holder. Columnar holder 20
Then, an exposure optical system 12 for each color is attached and housed inside the base of the photosensitive drum 10. In addition, as the exposure element, a linear element in which a plurality of light emitting elements such as FL (phosphor emission), EL (electroluminescence), and PL (plasma discharge) are arranged in an array is used.

An exposure optical system 12 as an image writing means for each color sets an exposure position on a photosensitive drum 10 between a scorotron charger 11 and a developing unit 13 with respect to the developing unit 13. It is arranged inside the photoconductor drum 10 in a state provided on the upstream side in the rotation direction of the drum 10.

The exposure optical system 12 performs image processing based on image data of each color sent from a separate computer (not shown) and stored in a memory, and then forms an image on a uniformly charged photosensitive drum 10. Exposure is performed to form a latent image on the photosensitive drum 10. The emission wavelength of the light-emitting element used in this embodiment is usually 6 for the toners of Y, M, and C, which have high translucency.
The wavelength in the range of 80 to 900 nm is good, but the wavelength may be shorter than this, since the color toner does not have sufficient translucency since image exposure is performed from the back surface.

The developing device 13 as a developing means for each color includes
Inside yellow (Y), magenta (M), cyan (C)
Alternatively, it contains a black (K) two-component (or one-component) developer and is formed of, for example, a cylindrical non-magnetic stainless steel or aluminum material having a thickness of 0.5 to 1 mm and an outer diameter of 15 to 25 mm, respectively. And a developing sleeve 13a as a developer carrier.

In the developing area, the developing sleeve 13a is kept in non-contact with the photosensitive drum 10 by a contact roller (not shown) with a predetermined gap, for example, 100 to 1000 μm, between the developing sleeve 13a and the rotating direction of the photosensitive drum 10. At the closest position, it rotates in the forward direction, and at the time of development, an AC voltage AC is superimposed on a DC voltage of the same polarity as the toner (in the present embodiment, a negative polarity) or a DC voltage with respect to the developing sleeve 13a. By applying the developing bias voltage, non-contact reversal development is performed on the exposed portion of the photosensitive drum 10. At this time, the precision of the development interval needs to be about 20 μm or less in order to prevent image unevenness.

As described above, the developing unit 13 transfers the electrostatic latent image formed on the photosensitive drum 10 by the charging by the scorotron charger 11 and the image exposure by the exposure optical system 12 in a non-contact state. Reversal development is performed with toner having the same polarity as the charge polarity of No. 10 (in the present embodiment, the photosensitive drum is negatively charged, and the toner has a negative polarity).

As shown in FIG. 2, the photosensitive drum 10 and a holder 20 as an exposure optical system holding member rotatably support the photosensitive drum 10 at the rear and front ends of the apparatus. Drum flanges 10A and 10B serving as photosensitive drum support members and optical system flanges 120A and 120B serving as exposure optical system support members that support holder 20.
And are integrally formed via means such as press fitting or screws. The photosensitive drum 10 includes a drum flange 10A as a photosensitive drum support member and a drum flange 1.
0B is the bearing B1 and the bearing B respectively with respect to the shaft 121 and the optical system flange 120B integrated with the optical system flange 120A of the holder 20.
It is rotatably supported via 2.

The shaft 121 has a shaft portion 121A for holding the photosensitive drum 10, and a support shaft 130 as shaft holding means having an engagement hole 130A is provided on the rear device board 70. The linear bearing B4 is fitted into the engagement hole 130A, and the receiving member 130
The support shaft 130 is fixed to the device substrate 70 on the rear side by screws or the like with the a interposed therebetween. The support shaft 130 is located at the center of the gear G2 that meshes with the drive gear G1, and rotatably supports a conductive member 131 that integrates the gear G2 via a bearing B3. On the other hand, the apparatus substrate 70 on the front side of the apparatus has an opening 70A through which the photosensitive drum 10 having the exposure optical system 12 fixed to the holder 20 can be inserted and removed.

The holder 20 inserts the shaft portion 121A of the shaft 121 into the linear bearing B4 provided on the support shaft 130 with respect to the device board 70 on the back side, and the shaft portion 121A
The engaging pin 121P inserted into the
The exposure optical system 12 is attached by regulating the angular relation position of the exposure optical system 12 by engaging with a V-shaped groove formed on the front side of the exposure optical system 12. The optical system flange 120C, which is a support member, is
With the front lid 120D pressed in the axial direction.
It is mounted at a predetermined position by fixing with.

A coupling 10C attached to the side surface of a drum flange 10A which is a photosensitive drum supporting member for supporting the photosensitive drum 10, a drive pin 131A attached to a side surface of a conductive member 131 integrated with a gear G2, and a set screw 51, the drum flange 10A and the gear G2
When the photoreceptor drum 10 having the holder 20 is integrated, the drum flange 10
A coupling 10C attached to the side of A is a drive pin 1 attached to the side of a conductive member 131 having a gear G2.
31A, and after engagement, the photoconductive drum 1 having the conductive member 131 having the gear G2 and the drum flange 10A
The drive pin 131 is set from the side of the photoreceptor drum 10 by using the set screw 51 with the center and the outer peripheral surface aligned.
A and the coupling 10C are fixed, and the drum flange 1
0A and the gear G2 are connected and fixed.

When the image forming body drive motor (not shown) is started by the start of the image formation, the rotational power of the drive gear G1 is transmitted to the photosensitive drum 10 via the coupling portion by the gear G2, and the photosensitive drum 10 is moved to the position shown in FIG. , And at the same time, application of a potential to the photosensitive drum 10 is started by the charging action of the Y scorotron charger 11.
After a potential is applied to the photosensitive drum 10, exposure by the first color signal, that is, an electric signal corresponding to Y image data is started in the Y exposure optical system 12, and the surface of the photosensitive drum 10 is rotated by the rotational scanning. An electrostatic latent image corresponding to the yellow (Y) image of the original image is formed on the photosensitive layer. This latent image is reversely developed in a non-contact state by the Y developing device 13, and a yellow (Y) toner image is formed on the photosensitive drum 10.

Next, the photoreceptor drum 10 places an M scorotron charger 11 on the yellow (Y) toner image.
A potential is applied by the charging action of the M exposure optical system 12
Exposure is performed using an electrical signal corresponding to the second color signal of m, i.e., magenta (M) image data.
Yellow (Y) by non-contact reversal development
A toner image of magenta (M) is formed on the toner image of FIG.

According to the same process, the cyan (C) toner image corresponding to the third color signal is further processed by the C scorotron charger 11, the exposure optical system 12 and the developing device 13, and the K scorotron charger 11. , Exposure optical system 1
A black (K) toner image corresponding to the fourth color signal is sequentially superimposed and formed by the second and developing units 13, and a color toner image is formed on the peripheral surface within one rotation of the photosensitive drum 10. You.

As described above, in this embodiment, Y, M,
The exposure of the organic photosensitive layer of the photoconductor drum 10 by the C and K exposure optical systems 12 is performed through a transparent substrate from the inside of the photoconductor drum 10. Therefore, the exposure of the image corresponding to the second, third, and fourth color signals can form an electrostatic latent image without being shielded by the previously formed toner image, which is preferable. Photoconductor drum 1
0 may be exposed from outside.

On the other hand, the recording paper P as a transfer material is sent out from a paper feed cassette 15 as a transfer material storage means by a feed roller (no code), fed by a feed roller (no code), and fed to a timing roller. It is conveyed to 16.

The recording paper P is synchronized with the color toner image carried on the photosensitive drum 10 by the driving of the timing roller 16, and the recording paper P is charged by the paper charger 1 as paper charging means.
Due to the electrification of 50, the toner is attracted to the conveyor belt 14a and fed to the transfer area. The recording paper P, which is closely transported by the transport belt 14a, is moved around the photosensitive drum 10 by a transfer unit 14c as a transfer unit to which a voltage having a polarity opposite to that of the toner (positive polarity in the present embodiment) is applied in a transfer area. The color toner images on the surface are collectively transferred to the recording paper P.

The recording paper P on which the color toner image has been transferred is
The paper is discharged by a paper separation AC neutralizer 14h as a transfer material separating unit, separated from the transport belt 14a, and transported to the fixing device 17.

The fixing device 17 includes a heat ray fixing roller 17a as an upper roll-shaped heat ray fixing rotating member (upper fixing member) for fixing a color toner image, and a pressure roller 47a as a lower fixing member. Inside the heat ray fixing roller 17a, a halogen lamp 171g or a xenon lamp (not shown) that emits heat rays such as infrared rays or far infrared rays including visible light depending on the light source is disposed as heat ray irradiation means.

Heat ray fixing roller 17a and pressure roller 47a
The recording paper P is sandwiched by a nip portion N formed between
By applying heat and pressure, the color toner image on the recording paper P is fixed, and the recording paper P is sent by the paper discharge roller 18 and discharged to a tray on the upper portion of the apparatus.

The toner remaining on the peripheral surface of the photosensitive drum 10 after the transfer is transferred to a cleaning blade 19 provided in a cleaning device 19 as an image forming body cleaning means.
Cleaning is performed by a. The photosensitive drum 10 from which the residual toner has been removed is uniformly charged by the scorotron charger 11, and enters the next image forming cycle.

As shown in FIG. 3, a fixing device 17 includes a heat ray fixing roller 17a as a roll-shaped heat ray fixing rotating member (upper fixing member) having an upper elasticity for fixing a toner image on a transfer material. And a pressure roller 47a as a lower fixing member also having elasticity, each formed between the heat ray fixing roller 17a having elasticity and the pressure roller 47a, and having a width of 15 mm or less, preferably 5 mm or more. At a wide nip portion N, the recording paper P that enters the nip portion N and passes through the nip portion N is nipped, and the toner image on the recording paper P is fixed by applying heat and pressure. On the heat ray fixing roller 17a serving as a roll-shaped heat ray fixing rotating member (upper fixing member) provided on the upper side, the fixing separation claw TR3, the fixing oil cleaning, and the rotating direction of the heat ray fixing roller 17a from the position of the nip portion N. A roller TR1, a heat equalizing roller TR4, and an oil application roller TR2 are provided. Oil is applied to the heat ray fixing roller 17a by an oil application roller TR2 in which a felt member impregnated with oil is wound around a cylindrical aluminum pipe or paper tube. Is done. The oil on the peripheral surface of the heat ray fixing roller 17a is cleaned by the fixing oil cleaning roller TR1. Therefore, the heat uniformizing roller TR4 and
A temperature sensor TS1, which is a temperature detecting means for measuring the temperature of the heat ray fixing roller 17a, is provided on the peripheral surface of the heat ray fixing roller 17a which has been cleaned between the fixing oil cleaning roller TR1 and the oil application roller TR2. The transfer material after fixing is separated by the fixing separation claw TR3. In addition, a metal roller member having good thermal conductivity such as an aluminum material or a stainless steel material, or a heat equalizing roller TR using a heat pipe.
4, the heat generation temperature distribution on the peripheral surface of the heat ray fixing roller 17a heated by the heat ray absorption layer 171b is made uniform. The heat uniformizing roller TR4 equalizes the temperature unevenness of the heat ray fixing roller 17a in the vertical and horizontal directions due to the passage of the transfer material.

A heat ray fixing roller 17a as a heat ray fixing rotating member (upper fixing member) for fixing a toner image on a transfer material includes a cylindrical light-transmitting substrate 171a and a light-transmitting substrate 171a. A translucent elastic layer 171 on the outside (outer peripheral surface)
d, a heat ray absorbing layer 171b and a release layer 171c are provided in that order as a soft roller. Translucent substrate 17
A halogen lamp 171g or a xenon lamp (not shown), which is a heat ray irradiating means for emitting heat rays such as infrared rays or far infrared rays including visible light depending on the light source, is disposed inside 1a. Heat ray fixing roller 1 as rotating member for heat ray fixing
7a is configured as a highly elastic soft roller as described later. Heat rays emitted from a halogen lamp 171g or a xenon lamp (not shown) are used as heat ray absorbing layers 171b.
Thus, a heat-fixing rotary member in the form of a roll that can be absorbed and rapidly heated is formed.

Further, a pressure roller 47a as a lower fixing member includes, for example, a metal core 471a made of an aluminum material, and a silicon rubber layer or a fluorine rubber layer, or a silicon rubber layer formed on the outer peripheral surface of the metal core 471a. A roller member is formed by a sponge-shaped rubber roller layer 471b made of a thick rubber layer having a thickness of 5 to 20 mm using a foam material, and has a releasability on the outer side (outer peripheral surface) of the rubber roller layer 471b of the roller member. It is configured as an elastic soft roller coated with a tube 471c of a heat-resistant fluororesin such as PFA or PTFA. Further, a heat equalizing roller T using a metal roller member having good thermal conductivity, such as an aluminum material or a stainless steel material, which rotates by being in contact with the surface of the rubber roller 471b.
R4 is provided, and the heat uniformizing roller TR4 uniformizes the heat generation temperature distribution on the peripheral surface of the pressure roller 47a. As the heat uniformizing roller TR4, it is preferable to use a heat pipe that serves both heat storage and heat radiation. A metal pipe roller such as aluminum can be used instead of the pressure roller 47a.

A flat nip N is formed between the upper soft roller and the lower soft roller, and the toner image is fixed.

TS1 is a temperature sensor which is mounted on the upper heat ray fixing roller 17a and is a temperature detecting means using, for example, a contact type thermistor for controlling the temperature. TS2 is mounted on the lower pressure roller 47a. For example, a temperature sensor using a contact-type thermistor for performing temperature control. As the temperature sensors TS1 and TS2, a non-contact type sensor can be used in addition to a contact type sensor.

The configuration of the heat ray fixing roller 17a is shown in FIG.
This is shown in the cross section of FIG. The cylindrical translucent substrate 171a has a thickness of 1 to 20 mm, preferably 2 to 5 mm,
Pyrex glass, sapphire (Al ₂ O ₃ ), ceramic material such as CaF ₂ that transmits heat rays such as infrared rays or far infrared rays from a halogen lamp 171 g or a xenon lamp (not shown) (thermal conductivity is (5 to 20) × 10 ^-3 J / cm
S · K, specific heat (0.5-2.0) × J / g · K, specific gravity 1.5-3.0) are mainly used. A translucent resin using polyimide, polyamide, or the like (having a thermal conductivity of (2 to 4) × 10 ⁻³ J / cm · s · K and a specific heat of (1 to
2) × J / g · K, specific gravity of 0.8 to 1.2) can also be used.

The light-transmitting elastic layer 171d has a thickness of 0.5 mm.
As described above, preferably, a silicon rubber layer having a thickness of 6 mm or less is used, and is formed of a heat-transmissive silicon rubber layer or a fluoro rubber layer (base layer) that transmits heat rays (infrared rays or visible rays including visible light depending on the light source). Translucent elastic layer 17
As 1d, in order to cope with a high speed, a method of improving the thermal conductivity by blending a powder of a metal oxide such as silica, alumina or magnesium oxide as a filler into the base layer is adopted. 10) × 10 ⁻³ J / cm · s ·
K, specific heat is (1-2) × J / g · K, specific gravity is 0.9-
A 1.0 silicon rubber layer or a fluorine rubber layer is used. The silicon rubber layer and the fluorine rubber layer are made of a light-transmissive substrate using a glass member having a thermal conductivity of (5-20) × 10 ⁻³ J.
/ Cm · s · K), it acts as a layer having a certain degree of heat insulation. When the thermal conductivity is increased, the rubber hardness generally tends to increase. For example, a rubber having a normal hardness of 40 Hs tends to have a hardness close to 60 Hs (JIS, A rubber hardness). Preferred rubber hardness is 5 Hs or more and 60 Hs or less (JIS, A rubber hardness). Most of the translucent elastic layer 171d of the heat ray fixing rotating member is occupied by the base layer, and the amount of compression during pressurization is determined by the rubber hardness of the base layer. The intermediate layer of the light-transmitting elastic layer 171d is made of a 20 to 300 μm fluorine-based rubber as an oil-resistant layer to prevent oil swelling.
It is preferable to form it with a thickness of m. The wavelength of the heat ray passing through the translucent elastic layer 171d is 0.1 to 20 μm.
m, preferably 0.3 to 3 μm, the filler used as a hardness or thermal conductivity modifier described above is:
The particle size is １ ／, preferably １ ／ or less of the wavelength of the heat ray,
Titanium oxide, aluminum oxide, oxide having an average particle diameter of 1 μm or less, preferably 0.1 μm or less, including primary and secondary particles, and having a heat ray transmission property (an infrared ray or a far infrared ray including visible light depending on a light source). Fine particles of metal oxides such as zinc, silicon oxide, magnesium oxide, and calcium carbonate are dispersed in a resin binder.
d may be formed. It is preferable that the average particle diameter including the primary and secondary particles in the layer is 1 μm or less, preferably 0.1 μm or less in order to prevent light scattering and reach the heat ray absorbing layer 171b. By providing the translucent elastic layer 171d, the heat ray fixing roller 17a as a heat ray fixing rotating member is provided.
Is configured as a highly elastic soft roller.

As the heat ray absorbing layer 171b, the remaining heat rays emitted from the halogen lamp 171g or the xenon lamp (not shown) and absorbed by the light transmitting base 171a and the light transmitting elastic layer 171d are used as the heat transmitting layer 171b. A heat ray fixing rotating member capable of absorbing 90 to 100%, preferably 95 to 100% of heat rays, which is about 100% of the heat rays transmitted through the 171a and the light transmitting elastic layer 171d, by the heat ray absorbing layer 171b and capable of rapid heating. As shown in FIG.
Carbon black, graphite, iron black (Fe ₃ ) in the silicone rubber or fluoro rubber used in 1d, or in the resin binder.
A heat ray absorbing member having a thickness of 10 to 500 μm, preferably 20 to 100 μm using a heat ray absorbing member mixed with powders such as O ₄ ), various ferrites and compounds thereof, copper oxide, cobalt oxide, and red iron oxide (Fe ₂ O ₃ ). The layer 171b is formed on the outside (outer peripheral surface) of the translucent elastic layer 171d by coating or spraying. The heat conductivity of the heat ray absorbing layer 171b is the same as that of the base layer of the translucent elastic layer 171d (the heat conductivity is (1 to 10)).
× 10 ⁻³ J / cm · s · K) (3 to 10)
0) × 10 ⁻³ J / cm · s · K. The specific heat of the heat ray absorbing layer 171b is (〜2.0) × J / g.
K, specific gravity is 〜0.9. Heat ray absorbing layer 171
As b, a metal roller member such as a nickel electroformed roller may be provided with a similar thickness. At this time, it is preferable that the inside (the inner peripheral surface) is subjected to black oxidation treatment in order to absorb heat rays. If the heat ray absorption rate in the heat ray absorption layer 171b is lower than about 90%, for example, about 20 to 80%, the heat ray leaks, and the heat ray fixing roller 17a as a heat ray fixing rotating member forms a monochrome image due to the leaked heat ray. When the black toner adheres to the surface of the specific position of the heat ray fixing roller 17a due to filming or the like, heat is generated from the adhering portion due to the leaked heat rays, and heat generated by heat ray absorption is further superimposed on the portion, thereby causing heat ray absorption. The layer 171b is damaged. Further, when used for forming a color image, the absorption efficiency of the color toner is generally low, and there is a difference in the absorption efficiency between the color toners, resulting in poor fixing or uneven fixing. Accordingly, the remaining heat rays emitted from the halogen lamp 171g or the xenon lamp (not shown) and absorbed by the light-transmitting base 171a and the light-transmitting elastic layer 171d form the light-transmitting base 171a and the light-transmitting elastic layer 171d. The heat ray absorption rate of the heat ray absorption layer 171b is about 100%, which is equivalent to 90 to 90%, so that the heat ray transmitted through the heat ray absorption layer 171b is completely absorbed by the heat ray absorption layer 171b.
100%, preferably 95 to 100%. Thereby, the color toner, which is difficult to fix by heat rays due to different spectral characteristics, is favorably melted. Particularly, in the color image formation in FIG. 1, it is difficult to fix by heat rays due to different spectral characteristics. The superimposed color toner image on the transfer material having a thick toner layer is fused well.
When the thickness of the heat ray absorbing layer 171b is less than 10 μm and thin, the heating rate by the heat ray absorption in the heat ray absorbing layer 171b is high, but the heat ray absorbing layer 1
This may cause breakage or insufficient strength of the heat ray absorbing layer 17b.
If the thickness of 1b exceeds 500 μm and becomes too thick, heat conduction becomes poor or the heat capacity becomes large, so that rapid heating becomes difficult. The heat ray absorption rate of the heat ray absorption layer 171b is approximately 100%
90 to 100%, preferably 95 to 100%, or the thickness of the heat ray absorbing layer 171b is 10 to 500 μm.
m, preferably 20 to 100 μm, local heat generation in the heat ray absorbing layer 171b is prevented, and uniform heat generation is performed. The wavelength of the heat ray projected on the heat ray absorbing layer 171b is 0.1 to 20 μm, preferably 0.3 to 20 μm.
Since the particle size is 3 μm, an adjuster for hardness and thermal conductivity is added as a filler, but the average particle size including primary and secondary particles having a particle size of ２, preferably １ ／ or less, of the wavelength of the heat ray is added. Titanium oxide, aluminum oxide, zinc oxide having a diameter of 1 μm or less, preferably 0.1 μm or less, which is heat-transmissive (in some cases, transmits infrared light or far-infrared light including visible light).
The heat ray absorbing layer 171b may be formed by dispersing 5 to 50% by weight of fine particles of a metal oxide such as silicon oxide, magnesium oxide, and calcium carbonate in a resin binder.
This allows the heat rays to enter the heat ray absorbing layer 171b and prevent heat generation at the interface. In this way, the heat capacity of the heat ray absorbing layer 171b is reduced so that the temperature rises immediately. Therefore, the temperature of the heat ray fixing roller 17a as a heat ray fixing rotating member is lowered, and the fixing unevenness occurs. To prevent. As the heat ray absorbing layer 171b, carbon black, graphite, iron black (Fe ₃ O ₄ ), various ferrites and their compounds, copper oxide, cobalt oxide, red iron oxide (F)
e ₂ O ₃ ) may be used. As the heat ray absorbing layer 171b, a metal film member such as a nickel electroformed belt can be used. At this time, it is desirable that the inside (inner peripheral surface) be subjected to black oxidation treatment in order to absorb heat rays.

The PF having a thickness of 20 to 100 μm is provided on the outside (outer peripheral surface) of the heat ray absorbing layer 171 b separately from the heat ray absorbing layer 171 b in order to improve the releasability and fixing property with the toner.
A (fluororesin) tube coated, fluororesin (PFA or PTFE) paint applied to 20 to 100 μm, or silicone rubber or fluororubber molded to a layer thickness of 20 to 500 μm. (3-10
0) A release layer 171c of × 10 ⁻³ J / cm · s · K is provided (separation type).

Further, as shown in the cross section in FIG.
Carbon black, graphite, iron black (Fe _ThreeO_Four) And various blowjobs
And its compounds, copper oxide, cobalt oxide, red iron oxide
(Fe_TwoO_Three) Etc.
Resin (PFA or PT)
FE) mixed with paint or silicone rubber or fluorine rubber
The heat ray absorbing layer 171 described above with reference to FIG.
b and the release layer 171c as a single unit having releasability.
The layer 171B is formed on the outer side (outer peripheral surface) of the translucent substrate 171a.
Form outside (outer peripheral surface) of the formed translucent elastic layer 171d
To form an elastic roll-shaped rotating member for fixing heat rays.
May be implemented. The thermal conductivity of the combined layer 171B is a heat ray absorbing layer.
171b is substantially the same as the thermal conductivity of (3-100) × 10
^-3J / cm · s · K. As mentioned above,
Lamp 171g or a xenon lamp (not shown)
The light-transmitting substrate 171a and the light-transmitting elastic layer 171d are
The remaining heat rays absorbed by the transparent base 171a and the transparent base 171a
Heat rays transmitted through the photoelastic layer 171d are completely absorbed.
As described above, the heat ray absorptivity of the dual-purpose layer 171B is set to approximately 100%.
90 to 100%, preferably 95 to 100%.
The heat ray absorptivity in the dual-purpose layer 171B is lower than about 90%.
If it is, for example, about 20 to 80%, heat rays leak and
Rotating member for fixing heat rays forms monochrome image due to heated heat rays
When used for heat ray fixing by filming, etc.
Leakage when black toner adheres to the surface of the transfer member at a specific position
Heat is generated from the attachment part by the heat rays, and further heat is generated in that part
Heat generation due to line absorption occurs repeatedly and damages dual-purpose layer 171B
I do. When used for color image formation,
Toner generally has low absorption efficiency and absorbs between color toners.
Poor fixing or fixing due to differences in yield efficiency
Become. Therefore, 171 g of a halogen lamp or xenon
Emitted from a lamp (not shown), the light-transmitting base 171a and
And the remaining heat rays absorbed by the translucent elastic layer 171d,
The light is transmitted through the light-transmitting substrate 171a and the light-transmitting elastic layer 171d.
Heat rays are completely absorbed in the heat ray fixing rotating member.
The heat ray absorptivity of the dual-purpose layer 171B is approximately 100%.
0-100%, preferably 95-100%. Ma
Further, local heat generation in the dual-purpose layer 171B is also prevented, and
Heat is generated. In addition, light is projected on the dual-purpose layer 171B.
The wavelength of the heat ray is 0.1-20 μm, preferably 0.3-3 μm.
μm, adjust hardness and thermal conductivity as filler
Agent is added, but the particle size is 1/2 of the wavelength of the hot wire, preferably
The average particle size including primary and secondary particles of 1/5 or less
Heat ray transmission of 1 μm or less, preferably 0.1 μm or less
(Depending on the light source, infrared or far infrared including visible light
Permeability) titanium oxide, aluminum oxide, zinc oxide,
Silicon oxide, magnesium oxide, calcium carbonate, etc.
Metal oxide fine particles dispersed in a resin binder
The dual-purpose layer 171B may be formed.

According to FIG. 5, the heat ray fixing roller 17a as a roll-shaped heat ray fixing rotating member (upper fixing member).
When the concentration distribution of the heat ray absorbing member described above is uniformly provided on the heat ray absorbing layer 171b as shown by the dotted line (a-1), the heat generation distribution of the heat ray absorbing layer 171b becomes as shown by the curve (b-1). The heat is concentrated on the heat ray absorbing layer 171b at the boundary, and the heat easily flows to the translucent elastic layer 171d side. Therefore, it is necessary to provide a concentration distribution and generate heat inside the heat ray absorbing layer 171b. Is preferred from the viewpoint of dispersing. For this reason, as shown by the dotted line (a-2) in the concentration distribution of the heat ray absorbing layer 171b, the inscribed translucent elastic layer 171 is shown.
The interface on the d side is made to have a low concentration and is gradually increased toward the outer peripheral surface side so as to be gradually higher, so that the thickness is smaller than the thickness of the heat ray absorbing layer 171b by ２〜 from the translucent elastic layer 171d side. 3
(About / 5 position) so as to obtain a concentration that absorbs 100% so as to be saturated. Thereby, the heat ray absorbing layer 17
The heat generation distribution due to the absorption of heat rays in 1b is represented by a curve (b-2).
As shown in the figure, the maximum value of the heat ray absorbing layer 171b is larger than the thickness t1 of the heat ray absorbing layer 171b from the interface.
From the 71d side, it is shifted so as to be located at about 1/3 to 2/5, and the outflow of heat is reduced.
Even when 1B is used, there is no influence even if the outer peripheral surface layer is shaved. Further, as shown by the dotted line (a-3),
It is preferable to form a saturated layer by providing an inclination, whereby the heat ray absorbing layer 171 is formed as shown by a curve (b-3).
The heat generation distribution b has a maximum value near the center of the heat ray absorbing layer 171b, and is formed in a parabolic shape having a minimum value near the interface and the outer peripheral surface of the heat ray absorbing layer 171b. Low, especially without the effect of heat outflow.
In short, if the absorption is sufficiently performed inside, the influence of the concentration on the outside disappears. There is no influence of shaving. Further, it is also possible to provide the above-mentioned inclination in the concentration distribution and adjust the heat generation distribution by changing the inclination angle.

As shown in FIG. 6, the outer diameter φ of the cylindrical light-transmitting substrate 171a of the heat-ray fixing roller 17a as a roll-shaped heat-ray fixing rotating member (upper fixing member) is 15 to 60 mm. As the thickness t, a thicker one is better in terms of strength and a thinner one is better in terms of heat capacity. However, from the relationship between strength and heat capacity, the outer diameter of the cylindrical light-transmitting base 171a is large. The relationship between φ and the thickness t is 0.025 ≦ t / φ ≦ 0.10, and preferably 0.035 ≦ t / φ ≦ 0.07. When the outer diameter φ of the translucent substrate 171a is 40 mm, the thickness t of the translucent substrate 171a is 1 mm ≦ t ≦ 4 mm, preferably 1.4 mm ≦ t ≦ 2.8 mm. When t / φ is less than 0.025 in the translucent substrate 171a, the strength becomes insufficient, and when t / φ exceeds 0.10, the heat capacity increases and the heating of the heat ray fixing roller 17a is prolonged. Further, even if it is referred to as a translucent substrate, depending on the material, 1
In some cases, about 20% of heat rays may be absorbed, and a thinner one is preferable as long as the strength can be maintained. Similarly, the translucent elastic layer 17
Even if it is 1d, depending on the material, it may absorb about 5 to 25% of the heat ray, and it is preferable that the thickness be as thin as possible in the range where the strength can be maintained.

The use of the fixing device 17 described with reference to FIG. 3 makes it possible to provide a fixing device which is resistant to deformation at the fixing portion (nip portion) and capable of quick start (rapid heating). Due to the pressure in the soft fixing portion (nip portion) due to the elasticity of the member and the heating by the heat absorbing layer of the rotating member for fixing heat rays, the color toner which is difficult to fix by the heat rays due to different spectral characteristics. The melting is performed favorably, and quick start (rapid heating) fixing of the color toner becomes possible. Also, an energy saving effect can be obtained.

In the above, the light-transmitting elastic layer 171d is not provided, but the light-transmitting base 171a and the heat ray absorbing layer 171b and the release layer 171c on the outer side (outer peripheral surface) of the light-transmitting base 171a.
Are provided in that order (or a dual-purpose layer 171B is provided on the outside (outer peripheral surface) of the light-transmitting base 171a) to form a heat ray fixing rotating member as a hard roller.
May be configured. In this case, the nip portion N formed between the pressure roller 47a and the soft roller has a structure in which the lower side is convex.

However, in the above-mentioned fixing device 17, the heat ray fixing roller 17a as a heat ray fixing rotating member is used.
Since a glass member, a translucent resin member, or the like is used as the translucent base member 171a provided on the heat-fixing roller 17a, the pressing is excessively performed during the pressing with the pressing roller 47a provided opposite to the heat ray fixing roller 17a. Then, the translucent substrate 171a is destroyed, or the broken translucent substrate 171a causes a halogen lamp 171g or a xenon lamp (not shown) as a heat ray irradiating means provided inside the translucent substrate 171a. There is a problem of being destroyed and causing a fire.

To solve these problems, first, the first
Next, a method of detecting the state of destruction of the light-transmitting substrate due to excessive pressing and prevention of fire by the heat ray irradiation means will be described with reference to FIGS. FIG. 7 is a diagram showing a first example in which conduction detection is used as a means for detecting the destruction of the light-transmitting substrate in the fixing device of FIG. 3 in a destructive state, and FIG. FIG. 9 is a diagram illustrating a second example in which conduction detection is used as destruction detection means for a transparent substrate in a destructive state, and FIG. 9 is a diagram illustrating the destruction detection means for a transparent substrate in the fixing device in FIG. First using translucency detection
FIG. 10 is a diagram showing a second example of using the translucency detection as the destruction detection means in the destruction state of the translucent substrate in the fixing device of FIG. 3, and FIG. FIG. 3 is a control block diagram of a fixing device according to the present invention.

According to FIG. 7 or FIG. 8 and FIG. 11, one end of the light-transmitting substrate 171a using a glass member or a light-transmitting resin member described above with reference to FIG. A C-shaped electrode ring DR1 is formed, and light is transmitted from both ends of the electrode ring DR1 to the surface (outer peripheral surface or inner peripheral surface) of the translucent substrate 171a along the longitudinal direction of the translucent substrate 171a. A serpentine conductive path DL1 is formed to cover the surface of the conductive base 171a. Conduction detection terminals KT1 and KT2 are provided at both ends of the electrode ring DR1, and through a switch member (not shown), both ends of a halogen lamp 171g and a xenon lamp (not shown) disposed inside the translucent base 171a. Connected to the lead wire WA from the section.

In the case of pressing with a pressure roller 47a (see FIG. 3, not shown in FIG. 7) provided opposite to the heat ray fixing roller 17a (see FIG. 3, not shown in FIG. 7), excessive pressure is applied. And the translucent substrate 171a is destroyed and cracks CK
Occurs, the snake-shaped conduction path DL1 is disconnected, the resistance value detected between the detection terminals KT1 and KT2 increases, and it is detected that the conduction path DL1 is in a non-conductive state.

When the conduction path DL1 is detected to be non-conductive by detecting conduction of the light-transmitting substrate 171a, as shown in FIG. In the state of energization, the light-transmitting substrate 17
The power supply to the halogen lamp 171g and the xenon lamp (not shown) as the heat ray irradiation means provided inside 1a is stopped.

As shown in FIG. 8, circular electrode rings DR1 and DR2 are formed at both ends of a light-transmitting substrate 171a using a glass member or a light-transmitting resin member. From the portion to the end of the electrode ring DR2, on the surface (outer peripheral surface or inner peripheral surface) of the translucent substrate 171a, along the rotation direction of the translucent substrate 171a.
A spiral conductive path DL2 is formed to cover the surface of 1a.
Electrode rings DR1 and DR2 at both ends of translucent substrate 171a
Are provided at the ends thereof, and lead terminals from both ends of a halogen lamp 171g and a xenon lamp (not shown) are provided through a switch member (not shown) provided inside the translucent substrate 171a. Connected to line WA.

When pressing with a pressure roller 47a (see FIG. 3, not shown in FIG. 8) provided opposite to the heat ray fixing roller 17a (see FIG. 3, not shown in FIG. 8), excessive pressure is applied. And the translucent substrate 171a is destroyed and cracks CK
Occurs, the spiral conduction path DL2 is cut, and the resistance value detected between the detection terminals KT3 and KT4 increases,
It is detected that conduction path DL2 is in a non-conduction state.

When the conduction path DL2 is detected to be non-conductive by detecting conduction of the light-transmitting substrate 171a, as shown in FIG. In the state of energization, the light-transmitting substrate 17
The power supply to the halogen lamp 171g and the xenon lamp (not shown) as the heat ray irradiation means provided inside 1a is stopped.

As described above, when the light-transmitting substrate using the glass member or the light-transmitting resin member is broken, the power supply to the heat-ray irradiating means is immediately stopped by detecting conduction of the light-transmitting substrate, and The occurrence of fire due to the destruction of the building is prevented.

According to FIG. 9 or FIG. 10, and FIG. 11, one side end of the light-transmitting substrate 171a using a glass member or a light-transmitting resin member as shown in FIG. For example, a light-emitting device PD1 using a light-emitting element such as a light-emitting diode is provided, and a light-receiving device PD2 using a light-receiving element such as a silicon element or a selenium element is provided at the other end to provide a transmittance detecting means. Constitute. The detection light emitted from the light emitter PD1 is transmitted through the inside of the light-transmitting substrate 171a in the axial direction of the light-transmitting substrate 171a and received by the light-receiving device PD2, and the detection light is transmitted to the light-transmitting substrate 171a. Detect changes in transmittance (light transmission). Lead wires WA from both ends of a halogen lamp 171g and a xenon lamp (not shown) provided inside the translucent substrate 171a are connected through a switch member (not shown).

In the case of pressing with a pressure roller 47a (see FIG. 3, not shown in FIG. 9) provided opposite to the heat ray fixing roller 17a (see FIG. 3, not shown in FIG. 9), excessive pressure is applied. And the translucent substrate 171a is destroyed and cracks CK
Occurs, the transmittance of the detection light decreases, and the light transmitting substrate 17
It is detected that 1a is in the non-light-transmitting state.

As shown in FIG. 11, the light-transmitting substrate 171a
When the transmittance of the detection light passing through is less than or equal to a predetermined transmittance stored in the ROM of the storage unit, it is detected by the transmittance detection (light transmission detection) that the light-transmitting substrate 171a is in the non-light-transmitting state. In this case, a halogen lamp 171g or a xenon lamp (not shown) is de-energized by operating a switch member or the like (not shown) through a fixing control unit, and a halogen as a heat ray irradiating means provided inside the translucent substrate 171a is provided. The power supply to the lamp 171g and the xenon lamp (not shown) is stopped.

As shown in FIG. 10, a light-emitting element such as a light-emitting diode and a light-emitting element such as a silicon element or a selenium element are provided on one side end of a light-transmitting substrate 171a using a glass member or a light-transmitting resin member. A photocoupler PC1 as a reflectance detecting means, which is a light receiving element, is provided, and a reflection film RS1 is provided on the other end of the light-transmitting substrate 171a. The detection light emitted from the photocoupler PC1 is transmitted in the axial direction of the light-transmitting base 171a through the inside of the light-transmitting base 171a, and the detection light reflected by the reflection film RS1 is received again by the photocoupler PC1 and detected. Light transmitting substrate 171
The change in the reflectance (transparency) of a is detected. Translucent substrate 1
Lead wires WA from both ends of a halogen lamp 171g and a xenon lamp (not shown) provided inside 71a are connected through a switch member (not shown).

The heat ray fixing roller 17a (see FIG. 3, FIG. 10)
Is not shown in the drawing).
(See FIG. 3, not shown in FIG. 10). If the pressure is excessive and the light-transmitting substrate 171 a is broken and cracks CK occur, the reflectance of the detection light decreases, and It is detected that the light base 171a is in the non-light-transmitting state.

As shown in FIG. 11, the translucent substrate 171a
When the reflectance of the detection light transmitted through is less than or equal to a predetermined reflectance stored in the ROM of the storage unit, the reflectance detection (light transmission detection) detects that the light-transmitting base 171a is in the non-light-transmitting state. In this case, a halogen lamp 171g or a xenon lamp (not shown) is de-energized by operating a switch member or the like (not shown) through a fixing control unit, and a halogen as a heat ray irradiating means provided inside the translucent substrate 171a is provided. The power supply to the lamp 171g and the xenon lamp (not shown) is stopped.

As described above, when the light-transmitting substrate using the glass member or the light-transmitting resin member is broken, the power supply to the heat ray irradiating means is promptly stopped by detecting the light transmission of the light-transmitting substrate, and The occurrence of fire due to the destruction of the irradiation means is prevented.

Second, with respect to the prevention of excessive pressing of the rotating member for heat ray fixing or the pressure roller, FIG. 12 or FIG.
3 and FIG. 11 described above. FIG.
FIG. 13 is a view showing the arrangement of a proximity preventing member in the fixing device for preventing the destruction of the light-transmitting substrate in the fixing device of FIG. 3; FIG. 6 is a diagram showing a moving method of the camera.

According to FIG. 12 or FIG. 13, as shown in FIG. 12, a side cross section of the fixing device 17, a heat ray fixing roller 17 a, which is a heat ray fixing rotating member (upper fixing member), is made of a light transmitting base 171 a. The light-transmitting elastic layer 171d, the heat ray absorbing layer 171b, and the release layer 171c are provided on the outside (outer peripheral surface) in this order as a soft roller having high elasticity. A resin flange JF1 as a holding member for the light-transmitting substrate 171a using a resin member such as a heat-resistant polyimide resin is provided at both ends of the outer peripheral surface of the light-transmitting substrate 171a in parallel with the central axis of the light-transmitting substrate 171a. Due to the resin flange JF1 having a large coefficient of thermal expansion provided at the outer (outer peripheral surface) end of the light-transmitting substrate 171a, the light-transmitting substrate 171a mainly using a glass member is damaged by thermal expansion during heating. Is prevented. Hot-wire fixing roller bearing B5, which is a bearing member of a hot-wire fixing rotary member press-fit into bearing holder BH1
A resin flange JF1 is fitted into the
7a is held rotatably.

Further, the core metal 471a and the rubber roller layer 471
and a pressure roller 47a as a lower fixing member formed as an elastic soft roller formed by a heat-resistant fluororesin tube 471c and the like, as described later, presses and releases pressure of the pressure roller 47a. In a state in which the pressure roller 47a is pressed against the upper heat ray fixing roller 17a by the pressure releasing means, both ends of the pressure roller 47a are fitted into bearings B6 which are press-fitted into bearing holders BH2 provided on both side ends, and are rotatably held. .

A flat (see FIG. 3) nip N is formed between the upper soft roller having high elasticity and the lower soft roller, and the toner image is fixed.

The gear Ga provided on the fixing side plate SB and coupled to the fixing driving motor M1 is driven by a driving gear Gb, and is fixed to one end of the core metal 471a of the pressure roller 47a, and meshes with the driving gear Gb. It is rotated and the pressure roller 47 is rotated.
is driven to rotate, and the heat ray fixing roller 17a is driven to rotate. The drive gear Gb and the gear Ga are connected by an endless coupling belt CB. At the time of pressure bonding or pressure release to be described later, as shown in FIG. 13, the pressure roller 4 coupled to the drive gear Gb by the coupling belt CB.
The gear Ga provided at the end of 7a is rotated along the arc of the drive gear Gb (displaceable in the arc direction) around the drive gear Gb of the pressure roller 47a, and pressure bonding or pressure release is performed.

The press-release means for performing the press-press and the press-release will be described below. The eccentric cam HC rotated by the driving of the pressure driving motor M2 provided at one end of the fixing device 17
When the slider reaches the upper fulcrum, the slide lever S1 that slides on the guide surface GP2 rises, so that the slide lever S
The pressing spring S disposed between the spring receiver SPA provided at the upper end of L1 and the spring receiver SPB provided at the lower end of the bearing holder BH2 holding the pressure roller 47a.
Pa presses the bearing holder BH2 against the pulling force of the spring SP1, the bearing holder BH2 is raised, and the pressing roller 47a is pressed against the heat ray fixing roller 17a. Eccentric cam HC driven by pressure drive motor M2
Of the bearing holder BH2
Is lowered, and the pressure roller 47a is released from pressure bonding.

The heat ray fixing roller 1 of the pressure roller 47a
When the heat ray fixing roller 17a and the pressure roller 4a are pressed together, the heat ray fixing roller 17a and the pressure roller 47a are excessively pressed and the light-transmitting substrate 171a is not broken.
7a, the stopper ST1 as an approach prevention member provided at a predetermined position is abutted against the raised bearing holder BH2 to stop the upward movement of the bearing holder BH2 due to the pressing of the pressing spring SPa. The amount of movement of the pressure roller 47a is restricted to an appropriate amount. Further, the spring receiver SPA to be raised is abutted by a stopper ST2 as a proximity prevention member provided at a predetermined position, and the upward movement of the bearing holder BH2 due to the pressing of the pressing spring SPa is stopped, and the moving amount of the pressure roller 47a is adjusted appropriately. The movement amount may be restricted.

In the above, the heat ray fixing roller 17a as a heat ray fixing rotating member is made movable, and the heat ray fixing roller 17a is provided with a pressure release means for performing pressure bonding and pressure release, and a proximity preventing member. May be restricted to an appropriate amount of movement.

As described above, excessive press-fitting to a light-transmitting substrate using a glass member or a light-transmitting resin member is prevented, and destruction of the light-transmitting substrate is prevented.

Third, FIGS. 14 and 15 show the prevention of destruction of the light-transmitting substrate due to excessive pressing and the prevention of fire due to the destruction of the heat ray irradiating means caused by the destruction of the light-transmitting substrate.
This will be described with reference to FIGS. 11 and 13 described above. FIG.
FIG. 15 is a view showing an arrangement of switch means for preventing the destruction of the translucent substrate and the firing of the heat ray irradiating means in the fixing device of FIG. 3, and FIG. 15 is a view showing the fixing device of FIG. FIG. 4 is a view showing the arrangement of position detecting means for preventing the destruction of the translucent substrate and the ignition of the heat ray irradiating means in FIG.

FIG. 14 or FIG. 15, and FIG.
According to FIGS. 1 and 13, as shown in FIG. 14, a side section of the fixing device 17, a heat ray fixing roller 17 a, which is a heat ray fixing rotating member (upper fixing member), is made of a glass member or a translucent resin member. A light-transmissive base 171a to be used and a light-transmissive elastic layer 171d, a heat ray absorbing layer 171b, and a release layer 171c provided in that order on the outer side (outer peripheral surface) thereof are configured as soft elastic rollers having high elasticity. Transparent Substrate 17
In parallel with the central axis of 1a, a resin flange JF1 as a holding member for the light-transmitting substrate 171a using a resin member such as a heat-resistant polyimide resin is provided at both ends of the outer peripheral surface of the light-transmitting substrate 171a. Due to the resin flange JF1 having a large coefficient of thermal expansion provided at the outer (outer peripheral surface) end of the light-transmitting substrate 171a, the light-transmitting substrate 171 mainly due to the thermal expansion of the light-transmitting substrate 171a using a glass member when heated.
a is prevented from being damaged. A resin flange JF1 is fitted into a hot-wire fixing roller bearing B5 which is a bearing member of a hot-wire fixing rotating member that is press-fitted into the bearing holder BH1, and the hot-wire fixing roller 17a is rotatably held.

The core metal 471a and the rubber roller layer 471
and a pressure roller 47a as a lower fixing member formed as an elastic soft roller formed by a heat-resistant fluororesin tube 471c and the like, as described later, presses and releases pressure of the pressure roller 47a. In a state in which the pressure roller 47a is pressed against the upper heat ray fixing roller 17a by the pressure releasing means, both ends of the pressure roller 47a are fitted into bearings B6 which are press-fitted into bearing holders BH2 provided on both side ends, and are rotatably held. . Translucent substrate 1
Lead wires WA from both ends of a halogen lamp 171g and a xenon lamp (not shown) provided inside 71a are connected to a switch SW1 as a switch means.

A flat (see FIG. 3) nip portion N is formed between the upper soft roller having high elasticity and the lower soft roller, and the toner image is fixed.

The drive gear Gb, which is provided on the fixing side plate SB and is coupled to the fixing drive motor M1, receives the drive, and is fixed to one end of the metal core 471a of the pressure roller 47a, and the gear Ga meshed with the drive gear Gb. It is rotated and the pressure roller 47 is rotated.
is driven to rotate, and the heat ray fixing roller 17a is driven to rotate. The drive gear Gb and the gear Ga are connected by an endless coupling belt CB. At the time of pressure bonding or pressure release to be described later, the gear Ga provided at the end of the pressure roller 47a coupled to the drive gear Gb by the coupling belt CB, as described above with reference to FIG. The drive gear Gb is rotated along the arc of the drive gear Gb (displaceable in the arc direction) around the drive gear Gb, and pressure bonding or pressure release is performed.

The means for releasing pressure for performing pressure bonding and pressure release will be described below. The eccentric cam HC rotated by the driving of the pressure driving motor M2 provided at one end of the fixing device 17
When the slider reaches the upper fulcrum, the slide lever S1 that slides on the guide surface GP2 rises, so that the slide lever S
The pressing spring S disposed between the spring receiver SPA provided at the upper end of L1 and the spring receiver SPB provided at the lower end of the bearing holder BH2 holding the pressure roller 47a.
Pa presses the bearing holder BH2 against the pulling force of the spring SP1, the bearing holder BH2 is raised, and the pressing roller 47a is pressed against the heat ray fixing roller 17a. Eccentric cam HC driven by pressure drive motor M2
Of the bearing holder BH2
Is lowered, and the pressure roller 47a is released from pressure bonding. 0
When the pressure roller 47a is pressed against the heat ray fixing roller 17a, the pressure between the heat ray fixing roller 17a and the pressure roller 47a becomes excessive, and the translucent substrate 171a is destroyed.
In order to prevent the halogen lamp 171g and the xenon lamp (not shown) from being destroyed by the destroyed heat ray fixing roller 17a and from causing ignition, the pressing force between the heat ray fixing roller 17a and the pressure roller 47a is adjusted appropriately. A switch SW1 is provided as a switch for detecting a predetermined amount of movement of the bearing holder BH2, and the amount of movement of the bearing holder BH2 by the above-described crimping release means for performing pressure bonding between the heat ray fixing roller 17a and the pressure bonding roller 47a and releasing pressure bonding. When the amount of movement of the pressure roller 47a exceeds a predetermined amount of movement, the switch SW1 is mechanically moved by the protrusion TS1 provided at the tip of the bearing holder BH2 in the direction of pressure movement and using an insulating member, as shown in FIG. The switch SW1 is turned off (turned off) by operating from the dotted line to the solid line.

As shown in FIG. 11, when the moving amount of the pressure roller 47a exceeds a predetermined moving amount stored in the ROM of the storage unit, the switch SW1 as a switch is mechanically operated through the fixing control unit. And halogen lamp 1
Turn off the 71g or xenon lamp (not shown),
The power supply to the halogen lamp 171g and the xenon lamp (not shown) as the heat ray irradiation means provided inside the translucent substrate 171a is stopped. Also, when an unillustrated sensor or a position detecting means described later with reference to FIG. 15 detects that the amount of movement of the pressing roller 47a is excessively larger than a predetermined moving amount stored in the ROM of the storage unit. Then, the pressure driving motor M2 provided in the pressure release unit described above is rotationally driven through the fixing control unit, and the pressure bonding between the hot-wire fixing roller 17a and the pressure roller 47a in the excessive pressure state is released.

In the above, the heat ray fixing roller 17a as a heat ray fixing rotating member is made movable, and on the side of the heat ray fixing roller 17a, a pressure releasing means for performing pressure bonding and pressure releasing and a switch means are provided. The supply of power to the halogen lamp 171g or the xenon lamp (not shown) is stopped, or the heat ray fixing roller 17a is in an excessively pressed state.
The pressing between the pressing roller 47a and the pressing roller 47a may be released.

[0086] By the above, excessive press-fitting to the light-transmitting substrate using a glass member or a light-transmitting resin member is prevented, and when the light-transmitting substrate is excessively pressed, power is supplied to the heat ray irradiating means. Is stopped immediately, and the occurrence of fire due to the destruction of the heat ray irradiation means is prevented.

Further, as shown in FIG.
A position detecting means composed of, for example, a light-emitting device PD11 using a light-emitting diode and a light-receiving device PD21 using a light-receiving element is arranged on the peripheral surface of a. Reflected light amount PD
It is detected that the heat ray fixing roller 17a and the pressure roller 47a are not at predetermined positions due to the reflected light coming off the light receiver PD21. If the reflected light of the light beam from the light emitter PD11 on the surface of the pressure roller 47a is captured by the light receiver PD21 as a predetermined light amount, the pressure roller 4
7a is detected as a crimped state.

As shown in FIG. 11, when the position detecting means detects that the moving amount of the pressure roller 47a exceeds the predetermined moving amount stored in the ROM of the storage unit and is not located at the predetermined position, it passes through the fixing control unit. By operating a switch member or the like (not shown), the halogen lamp 171g or the xenon lamp (not shown) is turned off, and the halogen lamp 171 as a heat ray irradiating means provided inside the translucent substrate 171a is provided.
The power supply to g and the xenon lamp (not shown) is stopped. When the position detecting unit detects that the moving amount of the pressure roller 47a exceeds a predetermined moving amount stored in the ROM of the storage unit and is not at the predetermined position, the fixing control unit shown in FIG.
In step 4, the pressure driving motor M2 provided in the pressure releasing means is rotated to release the pressure between the hot-wire fixing roller 17a and the pressure roller 47a in the excessive pressure state.

Further, in addition to the position detecting means on the side of the pressure roller 47a, the light emitting device PD12 as the position detecting means is further provided on the heat ray fixing roller 17a as a heat ray fixing rotating member.
And a photodetector PD22 using a light receiving element. The power supply to the halogen lamp 171g or the xenon lamp (not shown) as the heat ray irradiating means is stopped by the position detecting means of the heat ray fixing roller 17a, or the crimping state is excessive. The pressure release between the heat ray fixing roller 17a and the pressure roller 47a may be released.

In the above, the hot-wire fixing roller 17a is movable, and the hot-wire fixing roller 17a is provided with a pressure release means for performing pressure bonding and pressure release, and the hot-wire fixing roller 17a is provided with position detecting means. Further, the pressure detecting roller 47a is also provided with a position detecting means for stopping the power supply to the halogen lamp 171g and the xenon lamp (not shown) as the heat ray irradiating means, and for preventing the heat ray fixing roller 17a and the pressing roller 47a from being excessively pressed. Compression release may be performed.

As described above, excessive press-fitting to the light-transmitting substrate using a glass member or a light-transmitting resin member is prevented, and when the light-transmitting substrate is excessively pressed, power is supplied to the heat ray irradiating means. Is stopped immediately, and the occurrence of fire due to the destruction of the heat ray irradiation means is prevented.

[0094]

According to the first to third aspects, when the light-transmitting substrate using the glass member or the light-transmitting resin member is broken, the power supply to the heat ray irradiating means is stopped immediately, and the heat ray irradiating means is stopped. The occurrence of fire due to the destruction of the building is prevented.

According to the fourth or fifth aspect, excessive pressure-bonding to a light-transmitting substrate using a glass member or a light-transmitting resin member is prevented, and destruction of the light-transmitting substrate is prevented.

According to claim 6 or 7, excessive press-fitting to a light-transmitting substrate using a glass member or a light-transmitting resin member is prevented, and when the light-transmitting substrate is pressed excessively,
The power supply to the heat ray irradiating means is stopped immediately, and the occurrence of fire due to the destruction of the heat ray irradiating means is prevented.

[Brief description of the drawings]

FIG. 1 is a sectional view of a color image forming apparatus showing an embodiment of an image forming apparatus using a fixing device according to the present invention.

FIG. 2 is a side sectional view of the image forming body of FIG. 1;

FIG. 3 is an explanatory diagram illustrating a structure of a fixing device.

FIG. 4 is an enlarged cross-sectional configuration diagram of the roll-shaped rotating member for heat ray fixing in FIG. 3;

FIG. 5 is a diagram showing a concentration distribution of a heat ray absorbing layer of the roll-shaped heat ray fixing rotating member of FIG. 3;

6 is a view showing the outer diameter and thickness of a light-transmitting substrate of the roll-shaped heat ray fixing rotating member of FIG. 3;

FIG. 7 is a diagram showing a first example in which conduction detection is used as a means for detecting the destruction of a light-transmitting substrate in the fixing device of FIG. 3 in a destructive state.

FIG. 8 is a diagram showing a second example in which conduction detection is used as a means for detecting breakage of the light-transmitting substrate in the fixing device shown in FIG. 3 in a broken state.

FIG. 9 is a diagram showing a first example in which light transmission detection is used as a means for detecting breakage of a light-transmitting substrate in the fixing device of FIG. 3 in a destruction state.

FIG. 10 is a diagram illustrating a second example of using the translucency detection as the destruction detection means in the destruction state of the translucent substrate in the fixing device of FIG. 3;

FIG. 11 is a control block diagram of a fixing device according to the present invention.

FIG. 12 is a view showing the arrangement of a proximity preventing member in the fixing device for preventing the destruction of the translucent substrate in the fixing device of FIG. 3;

FIG. 13 is a diagram showing a method of moving the pressure roller of FIG. 12 during pressure bonding and pressure release.

FIG. 14 shows a switch means for preventing the destruction of the translucent substrate and the ignition of the heat ray irradiating means in the fixing device of FIG.
FIG. 3 is a diagram illustrating an arrangement in a fixing device.

FIG. 15 is a diagram showing an arrangement of a position detecting means for preventing the destruction of the translucent base and the firing of the heat ray irradiating means in the fixing device of FIG. 14;

[Explanation of symbols]

 REFERENCE SIGNS LIST 10 photoconductor drum 11 scorotron charger 12 exposure optical system 13 developing device 17 fixing device 17a heat ray fixing roller 47a pressure roller 171a light transmitting substrate 171B combined layer 171b heat ray absorbing layer 171c release layer 171d light transmitting elastic layer 171g halogen lamp DL1, DL2 Conductive path DR1, DR2, DR3 Electrode ring HC Eccentric cam KT1, KT2, KT3, KT4 Detection terminal M2 Crimping drive motor P Recording paper PC1 Photocoupler PD1, PD11 Light emitter PD2, PD21 Light receiver RS1, Reflective film SPA, SPB Spring receiver SPa Press spring ST1, ST2 Stopper SW1 Switch

 ────────────────────────────────────────────────── ─── Continued on the front page (72) Inventor Hiroshi Fuma 2970 Ishikawacho, Hachioji-shi, Tokyo Konica Corporation F-term (reference) 2H033 AA42 BA34 BA38 BB03 BB13 BB18

Claims (7)

[Claims] 1. A fixing device for fixing a toner image on a transfer material to the transfer material by heating and pressurizing, wherein the fixing device has a heat ray irradiating means for emitting heat rays therein, and has a light transmitting property with respect to the heat rays. A cylindrical light-transmitting base, and a heat-ray absorbing layer for absorbing the heat rays provided outside the light-transmitting base to form a roll-shaped heat-ray fixing rotating member, and covering the light-transmitting base. A fixing device, wherein a conduction path is formed, and power supply to the heat ray irradiation unit is stopped when the conduction path is in a non-conduction state. 2. The fixing device according to claim 1, wherein the conduction path is formed in a snake shape or a spiral shape. 3. A fixing device for fixing a toner image on a transfer material to the transfer material by heating and pressurizing, wherein the fixing device has a heat ray irradiating means for emitting heat rays therein, and has a light transmitting property to the heat rays. A cylindrical light-transmitting substrate, and a heat-ray absorbing layer that absorbs the heat rays provided outside the light-transmitting substrate to form a roll-shaped rotating member for fixing heat rays, and an axial direction of the light-transmitting substrate. A power supply to the heat ray irradiating means is stopped according to a change in transmittance or reflectance of the transmitted light. 4. A fixing device for fixing a toner image on a transfer material to the transfer material by heating and pressurizing, wherein the fixing device has a heat ray irradiating means for emitting heat rays therein, and has transparency to the heat rays. A cylindrical heat-transmissive substrate, and a heat-ray absorbing layer that absorbs the heat rays are provided outside the light-transmissive substrate to form a roll-shaped heat ray fixing rotating member, and are opposed to the heat ray fixing rotating member. A fixing device, wherein a proximity preventing member is provided on one of the heat ray fixing rotating member and the pressing roller. 5. The fixing device according to claim 4, wherein an amount of movement of the heat ray fixing rotating member or the pressure roller is restricted. 6. A fixing device for fixing a toner image on a transfer material to the transfer material by heating and pressurizing, wherein the fixing device has a heat ray irradiating means for emitting heat rays therein, and has a light transmitting property with respect to the heat rays. A cylindrical heat-transmissive substrate, and a heat-ray absorbing layer that absorbs the heat rays are provided outside the light-transmissive substrate to form a roll-shaped heat ray fixing rotating member, and are opposed to the heat ray fixing rotating member. And a pressure roller for forming a nip portion. The pressure roller performs pressure bonding and pressure release between the heat ray fixing rotating member and the pressure roller on either the heat ray fixing rotating member or the pressure roller. Release means is provided, and switch means is provided on one of the hot-wire fixing rotating member and the pressing roller, and the movement of the hot-wire fixing rotating member or the pressing roller by the pressing release means is performed. When exceeding the amount of movement, said by the movement of the rotary member for applying heat or the pressure rollers mechanically actuates the switch means, the fixing device characterized by stopping the power supply to the heat ray irradiating means. 7. A fixing device for fixing a toner image on a transfer material to the transfer material by heating and pressurizing, wherein the fixing device has a heat ray irradiating means for emitting heat rays therein and has a light transmitting property to the heat rays. A cylindrical heat-transmissive substrate, and a heat-ray absorbing layer that absorbs the heat rays are provided outside the light-transmissive substrate to form a roll-shaped heat ray fixing rotating member, and are opposed to the heat ray fixing rotating member. And a pressure detecting roller is provided. At least one of the heat ray fixing rotating member and the pressing roller is provided with a position detecting means, and the power supply to the heat ray irradiating means is stopped or the power detecting means detects the position by the position detecting means. A fixing device for performing pressure release between a hot-wire fixing rotating member and the pressure roller.