JP6885208B2 - Fixing device and image forming device - Google Patents

Description

The present invention relates to a fixing device and an image forming device.

In the electrophotographic image forming apparatus, a method of heating a fixing belt with a heater is known as a fixing device for fixing unfixed toner. In the above-mentioned method, in order to efficiently irradiate the fixing belt with radiant heat from the heater, there is a technique of arranging a reflective member in the fixing belt to shorten the warm-up time and save energy.

For example, Patent Document 1 discloses a fixing device in which a space (air layer) between a reinforcing member and an anti-member functions as a heat insulating layer, and the temperature of the reflecting member is easily raised by the heat of a heater.
Further, Patent Document 2 discloses a fixing device including a guide portion that guides the inner peripheral surface of the fixing belt, and the guide portion comes into contact with the inner peripheral surface of the fixing belt to effectively utilize the heat of the reflective member. ..
Further, in the fixing device, it is known that a lubricant is used in order to reduce friction and wear in the fixing belt.

However, when the lubricant is used, the oil volatilized from the lubricant adheres to the surface of the reflective member, the surface reflectance is lowered, and the heating efficiency to the fixing belt is lowered. As a result, there is a problem that the warm-up time becomes long with time and the TEC (Typical Electricity Consumption) value deteriorates.
In particular, when a low-viscosity lubricant is used to reduce the torque of the fixing device, the low-viscosity lubricant has a problem that the amount of volatilization and evaporation is larger than that of the high-viscosity lubricant.
In addition, in the configuration in which the reflective member is arranged above the halogen heater and the reflective surface faces downward, oil that volatilizes and evaporates upward tends to adhere, and the above-mentioned problems are likely to occur.

Regarding these problems, in the fixing device of Patent Document 1, it is easy to raise the temperature of the reflective member by heating with a heater, and even if the lubricant volatilizes, the lubricant is difficult to cool and solidify, and the reflective surface of the reflective member becomes dirty. However, it is not a configuration that suppresses the adhesion of volatile components of the lubricant itself.
Further, in Patent Document 2, the guide portion is configured to prevent the lubricant applied to the fixing belt from accumulating by the opening or the slit, but the volatile component of the lubricant adheres to the reflective member. It does not suppress.

The present invention has been made in view of the above problems in the prior art, and in a fixing device in which a reflecting member for reflecting radiant heat from a heating element is arranged, reflection of the reflecting member due to a volatile component volatilized from the lubricant The purpose is to suppress the decrease in the rate.

In order to solve the above-mentioned problems, the present invention includes an endless rotating body provided so as to be rotatable, and an endless rotating body.
Inside the contact member that comes into contact with the outer peripheral surface of the rotating body, a nip forming member that is arranged inside the rotating body and that comes into contact with the contact member via the rotating body to form a nip portion, and inside the rotating body. It is a fixing device including at least one arranged heating element and a reflecting member arranged inside the rotating body and reflecting radiant heat radiated from the at least one heating element toward the nip forming member. The reflective member is provided with a notch having a notch hole formed on the reflective surface facing the at least one heating element, and the oil absorbing member is positioned vertically below the notch. Further, the back surface of the reflective member facing the reflective surface is further provided .

According to the present invention, in a fixing device in which a reflecting member that reflects radiant heat from a heating element is arranged, it is possible to suppress a decrease in the reflectance of the reflecting member due to a volatile component volatilized from the lubricant.

It is a schematic block diagram of the copying machine which is an image forming apparatus which concerns on this embodiment. It is a schematic block diagram of an example of the fixing device which concerns on this embodiment. It is a schematic block diagram of another example of the fixing device which concerns on this embodiment. It is a figure explaining the adhesion of the volatile component volatilized from a lubricant to a reflective member. It is a figure explaining the notch part of Embodiment 1. FIG. It is a figure explaining the notch part of Embodiment 2. It is a figure explaining the structural example of the heating element which concerns on this embodiment. It is a figure explaining the notch part of Embodiment 3. It is a figure explaining the notch part of Embodiment 4. It is a figure explaining the effect of the notched portion of Embodiment 4. It is a figure explaining the notch part and the 2nd reflection part of Embodiment 5. It is a figure explaining an example of the shape of the cutout part of Embodiment 5. It is a figure explaining the shape of the cutout part and the second reflection part. It is a figure explaining the notch part of Embodiment 6.

Hereinafter, embodiments will be described with reference to the drawings. For the sake of clarity, the following description and drawings have been omitted or simplified as appropriate. In each drawing, components and corresponding parts having the same configuration or function are designated by the same reference numerals, and the description thereof will be omitted.

First, an embodiment of an electrophotographic image forming apparatus including a fixing device to which one embodiment of the present invention is applied will be described.
FIG. 1 is a schematic configuration diagram of a copying machine 500, which is an example of an image forming apparatus according to the present embodiment.
The copying machine 500 includes an image forming unit 200, a paper feeding unit 400 arranged below the image forming unit 200, and a scanner unit 300 arranged above the image forming unit 200.

The image forming unit 200 includes four image forming devices 1 (Y, M, C, K) corresponding to each color of yellow (Y), magenta (M), cyan (C), and black (K). Y, M, C, and K added after the numbers of each code indicate that the members are for yellow, magenta, cyan, and black (the same applies hereinafter). The four image forming devices 1 (Y, M, C, K) have almost the same configuration except that the colors of the toners they handle are different. Therefore, "Y" indicating the color of the toner to be used is described below. , "M", "C", and "K" are omitted as appropriate.

The image forming apparatus 1 includes a photoconductor 3 as an image carrier, a charging device 2 for charging the surface of the photoconductor 3, a developing device 5 as a developing means, and a cleaning device 7 for cleaning the photoconductor 3.

The image forming unit 200 includes a writing unit 100 for writing an electrostatic latent image on the photoconductor 3, an intermediate transfer belt 16 on which a toner image formed on the photoconductor 3 is transferred, and four photoconductors 3. It is provided with four primary transfer rollers 6 for primary transfer of the toner image to the intermediate transfer belt 16, respectively.
Further, a secondary transfer roller 26 is provided which forms a secondary transfer nip facing the intermediate transfer belt 16 and transfers the toner image on the intermediate transfer belt 16 to the transfer paper S as a recording material.
A resist roller pair 12 for temporarily holding the transfer paper S on standby is provided on the upstream side of the transfer paper S in the transport direction with respect to the secondary transfer nip.

The image forming unit 200 includes four toner bottles 20 (Y, M, C, K) for storing replenishment toner to be replenished in each of the developing devices 5 (Y, M, C, K) that consume toner. Further, a fixing device 9 as a fixing means is provided above the secondary transfer roller 26, and a paper ejection roller 18 is provided on the downstream side of the fixing device 9 in the transport direction of the transfer paper S.

The paper feed unit 400 has a paper feed cassette 10 and a paper feed roller 11 which are recording material storage units, and the paper feed cassette 10 loads the transfer paper S on the loading surface. The paper feed roller 11 is for separately feeding the transfer paper S loaded on the paper feed cassette 10 one by one.

The scanner unit 300 includes a contact glass 31 on which a document is placed. Further, in order to read and scan the document placed on the contact glass 31, the first traveling body 32 provided with the document illumination light source 32a and the first mirror 32b, and the second mirror 35a and the third mirror 35b are provided. The second traveling body 35 provided is provided. Further, a lens 33 and a CCD (CCD image sensor) 34 installed behind the lens 33 are provided.

Next, the operation of image formation of the copying machine 500 will be described.
When the document is placed on the contact glass 31 and the image forming operation is started, the document illumination light source 32a irradiates the light, and the reflected light reflected by the document is the first mirror 32b, the second mirror 35a, and the third mirror. It is reflected by the mirror 35b, imaged by the lens 33, and incident on the CCD 34.
The scanner unit 300 generates image information to be formed on the transfer paper S based on the light incident on the CCD 34.

In the image forming unit 200, the rotating photoconductor 3 is uniformly charged by the charging device 2, and the writing unit 100 is driven based on the above-mentioned image information.
The writing unit 100 emits irradiation light from a light source based on image information and scans the surface of the uniformly charged photoconductor 3 to form an electrostatic latent image on the photoconductor 3. The electrostatic latent image is developed by supplying a developer (toner) from the developing roller 15 of the developing apparatus 5, and becomes a toner image as a visible image.

On the other hand, while the toner image is being formed on the photoconductor 3, the transfer paper S is pulled out from the selected one of the plurality of paper cassettes 10 by the paper feed roller 11, and the tip thereof is resisted. It stands by in contact with the nip portion of the roller pair 12.
Then, the resist roller pair 12 starts rotating at the timing of superimposing the transfer paper S on the toner image on the intermediate transfer belt 16 on which the toner images of each color are superposed and transferred by the four primary transfer nips, so that the transfer is performed. Paper S is fed to the secondary transfer nip.
The transfer paper S on which the toner image is transferred by the secondary transfer nip is statically eliminated by contact with the static elimination brush, mechanically separated from the intermediate transfer belt 16, and then sent to the fixing device 9.

In the fixing device 9, the transfer paper S is heated and pressurized to fix the toner image on the transfer paper S.
The transfer paper S on which the toner image has been fixed after passing through the fixing device 9 is discharged onto the paper ejection tray 8 by the paper ejection roller 18.
The transfer residual toner remaining on the surface of the photoconductor 3 after passing through the primary transfer nip is removed from the photoconductor 3 by the cleaning device 7 and recovered. The surface of the photoconductor 3 from which the transfer residual toner has been recovered is statically eliminated by the static elimination device to prepare for the next image forming step.

In the above description, the image forming operation in which the image information of the document is read by the scanner unit 300 and the image is created based on the image information has been described.
The copying machine 500 can also create an image based on image information input from an external electronic device such as a personal computer.

The copying machine 500, which is the image forming apparatus of the embodiment, is an intermediate transfer method in which the toner image on the photoconductor 3 is transferred to the transfer paper S via the intermediate transfer belt 16 which is an intermediate transfer body.
The method of transferring the toner image to the transfer paper S is not limited to the intermediate transfer method, and may be a direct method of transferring the toner image directly from the photoconductor to the transfer paper S.

Next, a configuration example of a fixing device to which one embodiment of the present invention is applied will be described.
FIG. 2 is a schematic configuration diagram of an example of the fixing device according to the present embodiment.
The fixing device 9 is provided with a pressure roller 30 which is a contact member for rotationally driving, and a fixing belt (rotating body) 38 which is a substantially cylindrical fixing member.
Inside the cylindrical fixing belt 38, a pressure pad 60 and a stay member 61 constituting a nip forming member, and a first halogen heater 50a and a second halogen heater 50b as a plurality of heating elements are provided. There is.

As shown in FIG. 2, the first halogen heater 50a and the second halogen heater 50b are arranged on both sides in the vertical direction with the stay member 61 interposed therebetween.
Further, between the two halogen heaters 50 and the stay member 61, a reflective member 40 that reflects the radiant heat radiated from the halogen heater 50 toward the inner peripheral surface of the fixing belt 38 is arranged.

Further, at both ends of the fixing device 9 in the longitudinal direction, there are support side plates 70 that are a part of the structure of the copying machine 500 and support the constituent members of the fixing device 9 described above. Here, the longitudinal direction of the fixing device is a direction (Y direction) orthogonal to the paper surface in FIG. 2 and a direction parallel to the axis of the rotating body which is a fixing member.

The fixing belt 38 is a cylindrical heating rotating body that can be flexibly deformed, and has a cylindrical shape having an outer diameter of 30 [mm] and a thickness of 10 to 70 [μm], and a nickel (Ni) substrate. It has an elastic layer coated on the surface of the substrate.
The elastic layer is made of silicone rubber and has a thickness of 50 to 150 [μm].
A mold release layer made of a fluororesin having a thickness of 5 to 50 [μm] is formed on the outermost surface layer of the fixing belt 38 in order to enhance durability and ensure mold releasability.
Examples of the fluororesin include, but are not limited to, PFA (tetrafluoroethylene / perfluoroalkyl vinyl ether copolymer) and PTFE (polytetrafluoroethylene).
Further, the fixing belt substrate is not limited to nickel, and may be a metal substrate such as SUS (stainless steel) or a heat-resistant resin such as PI (polyimide).

The pressure roller 30 has an outer diameter of 30 [mm], and is formed of a hollow iron core metal 30a, an elastic layer 30b formed on the surface of the iron core metal 30a, and a release layer 30c.
The elastic layer 30b is made of silicone rubber and has a thickness of 5 [mm].
It is desirable to form a mold release layer 30c made of a fluororesin having a thickness of about 40 [μm] on the surface of the elastic layer 30b in order to improve the mold release property.
The pressure roller 30 is urged toward the fixing belt 38 by the urging means, and the pressure roller 30 and the fixing belt 38 are in pressure contact with each other.

The pressure pad 60 covers the resin portion 60a made of a resin material having high heat resistance such as LCP (liquid crystal polymer) and the resin portion 60a and is in sliding contact with the inner surface of the fixing belt 38, and the temperature in the longitudinal direction of the fixing belt 38. It is formed of a copper soaking portion 60b that makes the distribution uniform.
The pressure pad 60 sandwiches the fixing belt 38 and is in pressure contact with the pressure roller 30 to form a fixing nip SN.

The pressure pad 60 is supported by a stay member 61.
Both ends of the stay member 61 in the longitudinal direction are supported by the support side plates 70, and the pressing pressure of the pressurizing roller 30 against the pressurizing pad 60 is received by the stay member 61, which is a reinforcing member that reinforces the pressurizing pad 60 from the inside. It forms a fixing nip SN.

The two halogen heaters 50 are arranged on both sides in the vertical direction with the stay member 61 interposed therebetween, and both ends in the longitudinal direction are supported by heater folders located outside the support side plate in the longitudinal direction.
In the first halogen heater 50a, the first light emitting portion filament 51a is arranged in the longitudinal direction in a narrow region corresponding to the width of the small-sized transfer paper S.
In the second halogen heater 50b, the second light emitting portion filament 51b is arranged in the longitudinal direction in a region outside the width of the small size transfer paper S in the wide region corresponding to the width of the large size transfer paper S.
In the following description, when the first halogen heater 50a and the second halogen heater 50b are not particularly distinguished, they may be simply referred to as the halogen heater 50.

The reflective member 40 is arranged at a position where the halogen heater 50 and the stay member 61 face each other, and both ends in the longitudinal direction thereof are supported by support side plates.
The reflective member 40 is formed of an aluminum substrate, a silver paste applied to the surface of the substrate, and an antioxidant layer on the upper layer, and reflects the radiant heat of the halogen heater 50 toward the fixing belt 38 on the reflective surface 40F.
The reflective member 40 has a shape in which a plurality of plate-shaped members are bent and bent so as to block between the stay member 61, the pressure pad 60, and the halogen heater 50.
By forming the shape bent in this way, the reflective member 40 has a configuration (polygon) in which the angle of the surface of the reflective surface 40F at a position facing the halogen heater 50 changes. In other words, the reflection member 40 shown in FIG. 3 is composed of a plurality of reflection plane portions having different inclined reflection surfaces, and the reflection surface 40F is formed by the plurality of reflection surface portions.

Further, at a position where the perpendicular line drawn from the center of the halogen heater 50 to the reflecting surface 40F of the reflecting member 40 and the reflecting surface 40F intersect, a mountain-shaped shape 43 having this position as an apex 41 is formed.
By providing such a chevron shape 43, among the radiant heat radiated from the halogen heater 50, the radiant heat incident on the reflection surface 40F along the vertical line is incident on the slope of the chevron shape 43.
At this time, since the incident direction of the radiant heat and the slope of the mountain-shaped shape 43 are not at right angles, the radiant heat is reflected in a direction different from the incident direction.
Therefore, the radiant heat incident on the reflecting surface 40F can be reflected toward the fixing belt 38 while avoiding the passage of the halogen heater 50, and the radiant heat can be prevented from heating the halogen heater 50 itself.

Next, an example of a fixing device in which the shape of the reflective member is different from that of FIG. 2 will be described. FIG. 3 is a schematic configuration diagram of another example of the fixing device according to the present embodiment.
In FIG. 3, the configurations other than the reflective member 40 are the same as those in FIG. 2, and thus the description thereof will be omitted as appropriate. Further, in FIG. 3, the support side plate 70 is omitted.
The fixing device 9 arranges the reflective members 40a and 40b so as to cover the standing portion of the stay member 61 that stands up and supports the pressure pad 60. As shown in FIG. 3, the relevant portions of the reflecting members 40a and 40b are formed by the reflection plane portion 48A and the reflection plane portion 48C, which are two parallel and staggered plane portions, and the reflection plane portion 48A and the reflection plane portion 48C. It is formed by a reflection plane portion 48B which is an inclined plane portion to be connected. Further, the reflection members 40a and 40b have a reflection plane portion 48D adjacent to the reflection plane portion 48C.

Further, the halogen heater 50 is located at a position facing the reflection plane portion 48B, and the incident angle of the radiant heat incident on the reflection plane portion 48B is not perpendicular to the slope. Therefore, in the reflection plane portion 48B, the radiant heat is reflected in a direction different from the direction in which the radiant heat is incident, and it is possible to suppress the radiant heat reflected by the reflection plane portion 48B toward the halogen heater 50.
Therefore, as shown in FIG. 3, the radiant heat from the halogen heater 50 incident on the reflection plane portion 48B does not return to the halogen heater 50 but is reflected toward the fixing belt 38 on the opposite side of the pressure pad 60. ..
Therefore, by preventing the radiant heat from heating the halogen heater 50 itself (the glass tube constituting the halogen heater 50), the fixing belt 38 can be efficiently heated.

Further, the erecting portion of the stay 61 is erected in a direction orthogonal to the paper transport direction in the fixing nip SN and away from the fixing nip SN, and the reflection plane portion 48A and the reflection plane portion 48B are in the erecting direction of the standing portion. It is desirable to be parallel to. As a result, the installation space of the stay 61 and the reflective members 40a and 40b in the fixing belt 38 can be reduced, and the fixing device 9 can be downsized.

Although the fixing device to which one embodiment of the present invention is applied has been described with reference to FIGS. 2 and 3, the fixing device is not limited to these configuration examples, and may have other configurations. For example, if the fixing device is a fixing device in which the reflective member is located above the heating element and has a reflective surface facing the heating element, the cutout portion of one embodiment can be applied, and an advantageous effect can be obtained. it can.

Here, the influence of the volatile components volatilized from the reflective member and the lubricant on the reflectance of the reflective member will be described.
Regarding the fixing configuration in which the halogen heater and the reflecting member are arranged, factors affecting the heating efficiency include the halogen heater efficiency (output), the inner surface emissivity of the fixing belt, the shape of the reflecting member, and the reflectance of the reflecting member. ..
As the reflective member, a structure in which a protective layer is provided on a mirror surface layer made of a silver layer is used as the reflective film. The reflective member has a low heat absorption rate (0.03 to 0.05%), and the oil has a high heat absorption rate of about 0.9% and easily absorbs heat. In addition, the reflectance of the reflective member is lowered by deteriorating and discoloring the attached oil.
In the case of grease, the lubricant is composed of a base oil, a thickener, and a solid lubricant. Maintaining low torque can be achieved by lowering the viscosity of the base oil, but lowering the viscosity, that is, lowering the molecular weight, increases the amount of evaporation with respect to the heating temperature. Since the heated base oil moves upward due to vaporization, it easily adheres to the members in the vicinity of the upper part.

FIG. 4 is a diagram illustrating adhesion of volatile components volatilized from the lubricant to the reflective member.
The fixing belt 38 is frictionally slid by the pressure from the heat equalizing portion 60b and the pressure roller 30. In order to reduce this frictional force and further suppress wear due to friction, a lubricant 80, for example, a semi-solid material such as fluorine grease or silicone grease, or fluorine oil is placed on the inner surface of the fixing belt 38 or on the heat equalizing portion 60b in advance. , A liquid lubricant such as silicone oil can be used.

An increase in frictional resistance leads to an increase in the drive torque of the fixing device 9, and unless the output of the drive motor is suppressed to be equal to or lower than the output of the drive motor, the fixing device cannot be driven due to insufficient output of the drive motor, and problems such as jams occur. Although it is possible to deal with this by increasing the output of the drive motor, problems such as an increase in power consumption and an increase in cost due to an increase in the strength of the transmission drive gear to the drive motor also occur.
In order to maintain low frictional force, it is generally easy to achieve low torque by selecting a lubricant with a low oil viscosity.
Further, since the lubricant is in the vicinity of the heating element and the fixing belt 38 to be heated, a lubricant having high heat resistance is generally selected.

However, even if the above-mentioned fluorine oil and silicone oil having relatively high heat resistance are used, volatilization due to long-term heating cannot be completely suppressed in a high temperature environment by a heat source. Therefore, the volatile oil content 81 scatters upward in the vertical direction due to the radiant heat of the halogen heater 50. Since there is nothing inside the fixing belt 38 that generates an air flow in the first place, the scattered volatile oil content 81 adheres to the upper reflective member 40 as it is.
In a fixing device having a structure in which a reflective member 40 must be provided in the vicinity of a heat source, the reflectance is lowered by adhering a volatile lubricant component to the reflective surface 40F of the reflective member 40, and the warm-up time is extended over time. It ends up. For example, in the fixing device of FIG. 4, the chevron-shaped apex 41 provided on the reflective member 40 obstructs the flow of the scattered volatile oil content 81, and on the right side of the drawing from the apex 41, it loses its place and stays on the reflective surface of the reflective member. It becomes easy to adhere to 40F. The volatile oil content 81 adhering to the reflective surface 40F gradually accumulates and becomes cloudy, which may cause a problem that the reflectance of the reflective surface 40F is lowered.

The reflective member 40 is generally formed by using a mirror-like member having a high reflectance of about 90 to 97%. However, if the reflectance decreases due to a change in the refractive index due to the adhesion of the volatile oil content 81 to the surface, the amount of heat reaching the fixing belt 38 decreases and the amount of heat transferred to the stay member 61 increases.
The stay member 61 supports a pressure pad 60 that receives a load from the pressure roller 30, and the mechanical properties decrease due to the heating temperature, so that the load from the pressure roller 30 causes the stay member 61 to bend and deform with both ends as fulcrums. Will increase. As a result, the width of the nip width SN near the center in the longitudinal direction is reduced, and abnormal images such as improper fixing due to insufficient heat applied to the paper and offset, and bending of the nip surface may cause poor paper transportability.

Therefore, in the present embodiment, the volatile components adhering to the reflective surface are reduced by providing a notch portion having a notch hole formed at at least one position on the reflective surface of the reflective member. More specifically, a notch is provided on the reflective surface of the reflective member facing the heating element above, which is the direction in which the volatile component volatilized from the lubricant rises, and the volatile component is allowed to pass through the notch hole to allow the temperature. It is adhered to a reinforcing member with a low temperature (stay member 61, etc.). This makes it difficult for the lubricant vaporized upward to adhere to the reflective member, and suppresses a decrease in the reflectance of the reflective member.

Hereinafter, the details of the notch portion provided in the reflective member according to the present invention will be described. In each embodiment, the shape of the reflective member shown in FIG. 2 will be described, but the present invention may be applied to the shape of the reflective member 40b composed of the reflective plane portions 48A to 48D shown in FIG. 3 or the shape of other reflective members. It is possible. Further, even when the reflective member is composed of one plane, the notch portion of one embodiment can be applied.

Embodiment 1.
FIG. 5 is a diagram illustrating a notched portion of the first embodiment. A notch 82 is provided in a part of the reflective surface 40F of the reflective member 40. The cutout portion 82 is widely described in FIG. 5 for ease of explanation, but a slit-shaped hole having a width of 0.5 mm or less and a length of about 10 to 20 mm is arranged in the longitudinal direction. Is also good.
The notch 82 is a volatile component (volatile) volatilized from the lubricant on the reflective surface 40F of the reflective member 40, which faces the second halogen heater 50b and is located above the second halogen heater 50b. This is a portion in which a notch hole (micro hole, slit) through which the oil component 81) passes is formed.
In the figure, an example of the movement path of the volatile oil content 81 is indicated by an arrow. Of the two arrows, one represents a state in which it passes through the notch 82 and moves to a surface facing the reflecting surface of the reflecting member, and the other moves to a region outside the reflecting member 40. In the following drawings, an example of the movement of the volatile component is shown by using an arrow.

The cutout portion 82 is preferably provided at a location where the volatile component of the lubricant moves or stays, depending on the shape of the reflective member 40.
For example, the cutout portion 82 is adjacent to the reflection plane portion arranged at the uppermost position in the vertical direction and the reflection plane portion arranged at the uppermost position in the vertical direction among the plurality of reflection plane portions constituting the reflection member. It is preferable to provide it at least one of the reflection plane portions. Further, when it is provided in the reflection plane portion adjacent to the reflection plane portion arranged at the uppermost position in the vertical direction, it is preferable to provide the notch portion 82 in the upper portion of the reflection plane portion in the vertical direction. This is because the volatile components volatilized from the lubricant move upward in the vertical direction.
In the example of FIG. 5, the cutout portion 82 is preferably provided at an arbitrary position between the apex 41 and the bending point 42 of the reflective surface 40F where the volatile component tends to stay, and the cutout portion 82 is horizontal to the reflective surface 40F. It is more preferable to provide a range including the uppermost surface in the direction.

As described above, in the fixing device of the present embodiment, the reflective member is provided with a notch for passing the volatile component generated from the lubricant heated by the heating element, so that the volatile component is retained at a specific position of the reflective member. It is possible to suppress the decrease in reflectance for a long period of time without any problem. As a result, it is possible to prevent a warm-up delay and the occurrence of an abnormal image.

Embodiment 2.
FIG. 6 is a diagram illustrating a notched portion of the second embodiment.
In FIG. 6, the cutout portion 82 is provided on a line perpendicular to the upright surface 43 of the reflective member 40 and connecting the center of the second halogen heater 50b. Further, it can be said that the switching portion 82 is provided on the reflection plane portion adjacent to the reflection plane portion arranged at the uppermost position in the vertical direction.
The radiant heat radiated from the second halogen heater 50b returns to the second halogen heater 50b again due to the specular reflection of the reflecting member 40 when the center of the second halogen heater 50b is located at a position perpendicular to the reflecting member 40, and is fixed. It does not reach the belt 38. Therefore, the specular reflection position where the radiant heat is specularly reflected by the second halogen heater 50b is an inefficient location as a reflection surface.
By changing the reflection direction to an arbitrary angle like the apex 41 of the reflection member 40 described above, the direction of radiant heat reaching the fixing belt 38 can be adjusted. However, since the reflection is repeated, the reflectance is lowered.
By arranging the notch 82 through which the volatile oil component 81 passes at the specular reflection position and allowing the volatile oil component 81 to pass through the portion where the reflectance is originally low, the volatile oil component 81 is volatile without reducing the heating efficiency of the fixing device as much as possible. It is possible to reduce the problem that the component adheres to the reflective surface.

As described above, in the fixing device of the present embodiment, the notch portion provided in the reflecting member is provided on the line connecting the perpendicular line of the plane of the reflecting member and the center of the heat source. By providing the notch portion in the portion having poor reflectance in the specular reflection portion, it is possible to suppress the decrease in reflectance caused by the notch to the minimum.

Embodiment 3.
FIG. 7 is a diagram illustrating a configuration example of a heating element according to the present embodiment. FIG. 8 is a diagram illustrating a notched portion of the third embodiment.
As shown in FIG. 7, the first and second halogen heaters 50a and 50b are arranged with the stay member 61 interposed therebetween. Further, as shown in FIG. 8, the first halogen heater 50a is for heating small size paper, the central portion in the longitudinal direction of the fixing belt 38 is heated, and the second halogen heater 50b is a large size paper such as A3. It is for heating and heats the vicinity of the edge of the paper. In addition, the second halogen heater 50b is arranged on the lower side of the stay member 61 in the vertical direction.
The cutout portion 82 is provided in a non-heating portion (range S indicated by an arrow in FIG. 8) on the transport center side of the heat generating portion of the second halogen heater 50b. As a result, the reflective member 40 allows the volatile oil component 81 to pass through at a position that is not easily affected by the reflectance, and suppresses a decrease in efficiency.
In addition, this embodiment can be applied regardless of the case where the cutout portion 82 is provided at any of the positions described in each embodiment.

As described above, the fixing device of the present embodiment includes the notch portion of the reflective member in the range of the reflective surface facing the non-heat generating portion in the longitudinal direction of the heat source. As a result, the decrease in reflectance caused by providing the notch in the reflective member is suppressed, and the volatile component is notched at the place where the natural convection due to the heating temperature difference promotes the movement of the volatile component from the high temperature part to the low temperature part. It is possible to pass through the part and suppress the decrease in reflectance.

Embodiment 4.
FIG. 9 is a diagram illustrating a notched portion of the fourth embodiment. FIG. 10 is a diagram illustrating the effect of the notched portion of the fourth embodiment.
In this embodiment, as shown in FIG. 9, an embodiment in which the oil absorbing member 44 is provided in the fixing device will be described. First, with reference to FIG. 10, the occurrence of a defect due to the volatile oil content 81 will be described.
As shown in FIG. 10, after passing through the notch 82, the volatile oil content 81 is transmitted vertically downward on the back surface 43 of the upright surface 43 of the reflective member 40 (the surface of the reflective member 40 facing the reflective surface) and is reflected. It is deposited as a grease pool 45 on the lower end surface of the member 40. When the accumulated grease pool 45 travels along the surface of the reflective member 40 and wraps around the second halogen heater 50b on the opposite side, it covers the reflective surface and causes a decrease in reflectance.
As shown in FIG. 9, by arranging the oil absorbing member 44 on the back surface of the upright surface 43 of the reflecting member 40, the volatile oil content 81 is absorbed and recovered, thereby suppressing the decrease in reflectance.
As shown in the first embodiment, the oil absorbing member 44 of the present embodiment can be applied even when the position where the notch is provided is different, and the volatile component passing through the notch is reflected. It functions effectively when grease pools accumulate along the back surface of the member.

As described above, the fixing device of the present embodiment includes the oil adsorbent below the notch portion of the reflective member in the vertical direction. As a result, it is possible to suppress the possibility that the volatile component of the lubricant that has passed through the notch is transmitted to the back surface of the reflective member, the lubricant is accumulated on the vertical lower end surface, and adheres to the reflective surface side due to surface tension to reduce the reflectance.

Embodiment 5.
FIG. 11 is a diagram illustrating a notched portion of the fifth embodiment. FIG. 12 is a diagram illustrating an example of the shape of the notch portion.
As described above, the specular reflection position has poor heating efficiency of the fixing belt 38, and the efficiency is likely to be further reduced by cutting out the reflective member. In the configuration example of the third embodiment, the reduction in heating efficiency is suppressed by arranging the cutout portion 82 in the non-heating portion of the second halogen heater 50b. However, in a configuration in which the volatile oil content 81 adheres to the reflective member 40 over a wide range, it is preferable to provide the cutout portion 82 also in the heat generation width range (heat generation region) of the second halogen heater 50b.

Therefore, in the present embodiment, the second reflecting portion 46 is provided on the back surface side of the reflecting member 40 of the notch portion 82. The second reflecting portion 46 is preferably arranged on a line connecting the notch portion 82 and the second halogen heater 50b in order to supplement the reflecting surface due to the formation of the notch hole. By providing the second reflecting portion 46, the volatile oil component 81 is allowed to pass through while suppressing the decrease in reflectance.
The second reflecting portion 46 may be newly provided with another member as shown as an example in FIG. 11, or the reflecting member 40 may be deformed by drawing as shown in FIG. 12 to obtain the same effect. You can do it.

FIG. 13 is a diagram illustrating the shapes of the notch portion and the second reflecting portion.
FIG. 13A shows a shape in which the reflective member 40 is deformed by drawing processing, similarly to the cutout portion 82 of FIG. A slit hole is formed in the notch portion 82 as the notch hole, and the volatile component is moved from the slit hole to the back surface of the reflective member 40. Further, the inclined surface 40G formed by drawing the reflecting member 40 functions as a reflecting surface that reflects radiant heat from the second halogen heater 50b. For example, when the portion of the reflecting surface 40F provided with the cutout portion 82 is a specular reflecting surface, the inclined surface 40G functions as a non-specular reflecting surface, so that a decrease in reflectance can be suppressed.

FIG. 13B is a diagram showing a state in which the volatile component moves when another member is provided as the second reflecting portion 46. Volatile components move from the space (slit, opening) between the reflective member 40 and the second reflective portion 46 to the back surface of the reflective member 40.
FIG. 13C shows an example in which the back surface of the reflective member 40 has an opening smaller than the reflective surface 40F side and an inclined surface is formed around the notch hole with respect to the size of the notch hole. Since the inclined surface 40G reflects the radiant heat from the second halogen heater 50b, it is possible to compensate for the decrease in the reflecting surface 40F. Further, as in FIG. 13A, when the portion of the reflection surface 40F provided with the notch 82 is a specular reflection surface, the inclined surface 40G functions as a non-specular reflection surface and the reflectance is lowered. Can be suppressed.

The notch portions shown in FIGS. 13 (a) and 13 (c) are recesses protruding from the reflective surface 40F toward the back surface of the reflective member 40, and it can be said that a notch hole is formed in the portion protruding from the back surface. .. The notch hole is a slit-shaped hole in FIG. 13 (a), and corresponds to an opening in which the tip of the recess is notched in FIG. 13 (c).
Further, although not shown in the figure, it is also possible to add the second reflecting portion 46 shown in FIG. 13 (b) to the configuration example of FIG. 13 (c).

As described above, the fixing device of the present embodiment further includes a notch portion of the reflecting member and a reflecting surface facing the heating element on an extension line of the center of the heating element. As a result, even when discoloration of the reflective member occurs in the heat generating portion of the halogen heater, it is possible to secure a flow path of the volatile component from the notch portion without reducing the reflectance.

Embodiment 6.
FIG. 14 is a diagram illustrating a notched portion of the sixth embodiment.
In the fixing device of FIG. 14, both the first and second halogen heaters 50a and 50b are arranged below the stay member 61 and the reflecting member 40 so as to face the reflecting surface.
The cutouts 82 are provided at two positions of the reflection plane portion adjacent to the uppermost reflection plane portion among the reflection plane portions facing the first and second halogen heaters 50a and 50b above, and further, the cutout portions 82 are provided. One portion is provided on the reflection plane portion adjacent to the reflection plane portion on which the portion 82 is provided. As shown in FIG. 14, it is preferable to provide a plurality of notched portions 40 at locations where volatile components are likely to accumulate, depending on the shape of the reflective member 40.
Even in a configuration in which the heating element is arranged as shown in FIG. 14, the same effect as in each of the above embodiments can be produced.

As described above, according to each of the above embodiments, the volatile component generated from the lubricant does not easily adhere to the surface of the reflective member, and the fixing belt can be used without lowering the reflectance even after long-term use. It is possible to exert an advantageous effect of maintaining the action of efficiently heating. Therefore, with respect to the fixing device having a reflecting member in the vicinity of the halogen heater, the warm-up time delay and the TEC value are deteriorated without deteriorating the reflectance, especially even if the reflecting member faces downward on the reflecting surface. It is possible to use a lubricant that can achieve low torque without causing it.

The present invention has been described above based on the embodiments. The present invention is not limited to the embodiments, and can be appropriately modified within the scope of the present invention. Further, the image forming apparatus provided with the fixing apparatus of the present invention is not limited to a copying machine or a printer, but may be a facsimile or a multifunction device having a plurality of functions. In addition, various changes can be made without departing from the gist of the present invention.

9 Fixing device 30 Pressurizing roller 38 Fixing belt 40, 40a, 40b Reflecting member 40F Reflecting surface 40G Inclined surface 44 Oil absorbing member 45 Grease pool 46 Second reflecting part 48A to 48D Reflecting flat part 50a First halogen heater 50b Second Halogen heater 81 Volatile oil content 82 Notch

Japanese Patent No. 5549160 Japanese Unexamined Patent Publication No. 2016-161679

Claims (8)

An endless rotating body provided so that it can rotate,
A contact member that comes into contact with the outer peripheral surface of the rotating body,
A nip forming member arranged inside the rotating body and abutting with the contact member via the rotating body to form a nip portion.
With at least one heating element arranged inside the rotating body,
A fixing device including a reflecting member arranged inside the rotating body and reflecting radiant heat radiated from the at least one heating element toward the nip forming member.
The reflective member is provided with a notch portion having a notch hole formed in a reflective surface facing the at least one heating element above .
A fixing device characterized in that an oil absorbing member is further provided on the back surface of the reflecting member at a position vertically below the notch and facing the reflecting surface. An endless rotating body provided so that it can rotate,
A contact member that comes into contact with the outer peripheral surface of the rotating body,
A nip forming member arranged inside the rotating body and abutting with the contact member via the rotating body to form a nip portion.
With at least one heating element arranged inside the rotating body,
A fixing device including a reflecting member arranged inside the rotating body and reflecting radiant heat radiated from the at least one heating element toward the nip forming member.
The reflective member is provided with a notch portion having a notch hole formed in a reflective surface facing the at least one heating element above .
The notch portion is a recess protruding from the reflective surface toward the back surface of the reflective member facing the reflective surface, and is characterized in that a notch hole is formed in the portion protruding from the back surface. Fixing device. An endless rotating body provided so that it can rotate,
A contact member that comes into contact with the outer peripheral surface of the rotating body,
A nip forming member arranged inside the rotating body and abutting with the contact member via the rotating body to form a nip portion.
With at least one heating element arranged inside the rotating body,
A fixing device including a reflecting member arranged inside the rotating body and reflecting radiant heat radiated from the at least one heating element toward the nip forming member.
The reflective member is provided with a notch portion having a notch hole formed in a reflective surface facing the at least one heating element above .
The notch is formed so that the opening on the back surface of the reflective member whose notch hole faces the reflection surface is smaller than that on the reflection surface side, and the inclined surface between the reflection surface and the back surface is formed. A fixing device characterized by functioning to reflect the radiant heat. The reflection member is composed of a plurality of reflection plane portions having different inclinations.
The cutout portion includes a reflection plane portion arranged at the uppermost position in the vertical direction and a reflection plane portion adjacent to the uppermost reflection plane portion in the vertical direction among the plurality of reflection plane portions. The fixing device according to any one of claims 1 to 3, wherein the fixing device is provided in at least one of the above. The fixing device according to claim 4 , wherein the cutout portion is provided on a line connecting the vertical line of the reflecting surface and the center of at least one heating element. The at least one heating element includes a heating element having a heat generating portion and a non-heating portion in the longitudinal direction parallel to the axis of the rotating body.
The fixing device according to any one of claims 1 to 5 , wherein the cutout portion is provided in a range of the reflective surface facing the non-heating portion. Claims 1, 4 to the present invention are characterized in that a second reflecting portion for reflecting the radiant heat is formed on a line connecting the notch portion and the center of the at least one heating element. The fixing device according to any one of 6. An image forming apparatus including the fixing apparatus according to any one of claims 1 to 7.

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