JP4445801B2 - Image forming apparatus - Google Patents

Description

  The present invention relates to an image forming apparatus such as a copying machine, a printer, and a facsimile. More specifically, the present invention relates to a heated fixing roller, a heat radiated from a pressure roller, and a heat transferred from the pressure roller. The present invention relates to an image forming apparatus that insulates the peripheral device from heat, eliminates the thermal effect on the peripheral device, reduces power required for heating, collects power from the discharged heat by thermoelectric conversion, and saves energy.

  2. Description of the Related Art An image forming apparatus such as a copying machine using an electrophotographic process has a device having a heat source and a device susceptible to heat mounted in the apparatus main body. As the former, for example, a fixing device that has a heat source such as a halogen lamp and fixes an unfixed image transferred to the recording paper to the recording paper by heating and pressurizing with the heat source is known, while the latter is For example, by transferring toner to a photosensitive drum as an image carrier, a developing device that visualizes an electrostatic latent image on the photosensitive drum as an image, transfer is performed, and remains on the photosensitive drum A cleaning device (developer recovery device) that collects residual toner, a substrate on which electronic components are mounted, a writing unit that writes on a photosensitive drum with a laser, and the like are known.

  In recent years, image forming apparatuses have been increased in speed, space-saving, and miniaturization, the temperature of the heat source has been increased, and the apparatus having the heat source and the apparatus that is easily affected by heat are arranged close to each other. It has come to be. For this reason, a device that is easily affected by heat is greatly affected by exhaust heat from a device having a heat source.

  For example, when a developing device, a cleaning device, or the like is close to a heat source, there is a problem that the toner of the developing device or the cleaning device is hardened. For example, when the substrate is close, the device malfunctions. When the writing units are close to each other, there is a problem in that the frame constituting the unit is distorted and good writing cannot be performed. Furthermore, there is a problem that heat discharged from these image devices becomes a heat load of the office.

  With respect to the former problem, Patent Document 1 discloses an image in which a toner image is formed on an image support by developing an electrostatic latent image formed on the image support, and the toner image is transferred and fixed on a recording medium. In the forming apparatus, the toner image formed on the image support is transferred onto the intermediate transfer member, and then the recording medium is pressed against the intermediate transfer member to heat the toner image transferred to the intermediate transfer member. The image is fixed simultaneously with the transfer, but the intermediate transfer member is cooled by a Peltier element to prevent damage to the image support due to heat.

  Further, in Patent Document 2, in the image forming apparatus, the first apparatus is configured by a heat transfer element (Peltier element) disposed between a first apparatus (cleaning apparatus) that is easily affected by heat and a heat source (fixing apparatus). While absorbing the heat of the heat, the heat absorbed is exhausted to the second device, the first device is cooled, and the second device is kept warm, while achieving energy saving of the heat source, The temperature rise of the first device is prevented.

  Further, in Patent Document 3, in a method of thermally fixing an unfixed recording sheet on which an image is formed with toner, a nip portion where a heating roller or the like comes into pressure contact with the conveyance belt, and a conveyance belt which comes into contact with the toner image surface after pressure contact are connected to a Peltier element. In this case, the toner is cooled after the toner is melted, so that fixing can be performed without causing an offset without applying release oil or the like.

  In addition to the conventional examples as described above, the following image forming apparatus is known, and this image forming apparatus has a thermoelectric conversion device adjacent to the heat generating portion of the image forming apparatus main body and the heat generating portion of the accessory device. For example, a fixing device is exemplified as the heat generating portion. Further, the heat collecting device is provided adjacent to the heat generating portion, and the thermoelectric conversion device is provided adjacent to the heat collecting device. Depending on the presence or absence of the fixing operation, the thermoelectric conversion device or the heat collecting device may or may not be adjacent. Further, the thermoelectric conversion device or the heat collecting device is provided outside the fixing device. Furthermore, a power supply device that supplies electrical energy converted from heat as drive power for the image forming apparatus and the accessory device is provided, and a device that stores the electrical energy is provided.

  As described above, various conventional examples are known, but there is no one that tries to reduce the heat energy lost from the fixing device due to heat transfer or radiant heat, and the heat generated from the inside of the apparatus is reused. Currently, no technology has been developed.

  The present invention insulates the radiant heat and heat transferred from the heated fixing roller and pressure roller in the image forming apparatus to reduce the thermal influence on the peripheral device, and to save power in heating. It is a thing. Further, since a cost and a size of the apparatus are large for making a complete thermal insulation apparatus, a realistic price and size are achieved. And in this case, the point which provided the thermoelectric conversion element which is slightly transmitted outside and converts the thermal energy which leaks into electricity differs greatly.

Also, in different conventional examples, as thermoelectric conversion of exhaust heat at high temperature and low temperature, first, second, and third thermoelectric conversion devices are provided in the apparatus main body, and a heat collecting plate is provided so as to surround the fixing means. A first thermoelectric conversion device including a thermoelectric semiconductor element and a heat pipe is provided. The present invention insulates radiant heat from the heated fixing roller and pressure roller in the image forming apparatus and heat transferred to the outside through the parts constituting the fixing apparatus, and reduces the thermal influence on the peripheral device, And the point which provided the thermoelectric conversion element which aims at the power saving of a heating, and converts the low temperature thermal energy which leaks outside into electric power differs greatly.
JP-A-8-137277 JP 2000-98861 A JP 2001-42672 A

The present invention has been made in view of the actual situation of the above-described conventional example. By surrounding the fixing device having a built-in heat source with an insulating member, image forming can be performed in the fixing device of an image forming apparatus such as a copying machine, a printer, or a facsimile machine. Image that insulates the heat transferred from the fixing device installed in the device from the peripheral device affected by the heat, eliminates the thermal effect on the peripheral device, and reduces the input power to the fixing device An object is to provide a forming apparatus.
Also, to provide an image forming apparatus with high energy saving by converting heat discharged from the fixing device of the image forming apparatus into electric power using a thermoelectric conversion device and reusing it for driving other peripheral devices. Objective.

According to the first aspect of the present invention, there is provided a paper feeding / conveying means for feeding recording paper, an unfixed image forming means for forming an unfixed image on the recording paper, a fixing means for fixing the unfixed image by heat, In an image forming apparatus including a discharge conveyance unit that discharges a recording sheet on which an image is fixed by a fixing unit, the fixing unit is surrounded by a heat insulating member, and the heat insulating member is formed of a polymer material resin layer on a metal. A heat insulating body made of a pair of metal-resin layers formed with a multi-layer structure in which the resin layers are bonded to each other inside .

  According to a second aspect of the present invention, in the image forming apparatus according to the first aspect, the means having the heating element is a fixing means comprising a fixing roller and a pressure roller.

According to a third aspect of the present invention, in the image forming apparatus according to the first or second aspect , the heat insulating member has a thermoelectric conversion element on a surface thereof.

According to a fourth aspect of the present invention, in the image forming apparatus according to the third aspect , the thermoelectric conversion element has a heat sink in a heat radiating portion thereof.

According to a fifth aspect of the present invention, in the image forming apparatus according to the third or fourth aspect of the present invention, the image forming apparatus includes a power storage device that stores electric power converted thermoelectrically by the thermoelectric conversion device.

The effects of the first and second aspects of the invention are as follows: a paper feeding / conveying means for conveying the recording paper from the paper feeding unit; an unfixed image forming means for forming an unfixed image on the recording paper; An image forming apparatus including a fixing unit that performs fixing and a paper discharge conveyance unit that conveys a recording sheet on which an image has been fixed by the fixing unit. Insulate the heat discharged from the heat generating part of the roller from being transferred to the outside, reduce the thermal effect on the peripheral devices, and reduce the power required for heating the fixing roller and pressure roller Is possible. Further, as a heat insulating member, by using a laminated plate having a single layer or a multilayer structure, a heat insulating body composed of a set of metal-resin layers in which a polymer material resin layer is formed on a metal, a fixing roller of a fixing unit, It is possible to effectively reduce the heat transferred from the heat generating part of the pressure roller to the outside. As a result, the heat influence on the peripheral device is reduced, and the heating of the fixing roller and the pressure roller is reduced. Power saving is possible.

The effect of the invention of claim 3 is that by providing a thermoelectric conversion element on the surface of the heat insulating member, heat energy transferred and transferred to the surface of the heat insulating member is converted into thermoelectric power, and the converted electric power is transferred to the image forming apparatus. It can be used for other peripheral devices.

The effect of the invention of claim 4 is that a heat sink is provided in the heat radiating portion of the thermoelectric conversion element and one of the thermoelectric conversion devices is cooled, so that the temperature difference can be increased and the thermoelectric conversion efficiency can be improved.

According to the fifth aspect of the present invention, since the power storage device that stores the power converted by the thermoelectric conversion device is provided, it can be used as driving power for each device in the image forming apparatus. Can be supplied stably.

  The present invention relates to an image forming apparatus such as a copying machine, a printer, or a facsimile, which insulates heat discharged from a fixing unit that fixes an unfixed image on recording paper by heat from peripheral devices that are easily affected by heat, and fixing unit. The purpose is to provide a highly energy-saving image forming apparatus that recovers the heat discharged from the printer and reduces the input power to the fixing device and reuses it as electrical energy. A sheet feeding and conveying means for feeding recording paper, an unfixed image forming means for forming an unfixed image on the recording paper, a fixing means for fixing the unfixed image by heat, and an image formed by the fixing means. In the image forming apparatus provided with a paper discharge conveying means for discharging the fixed recording paper, the fixing means is surrounded by a heat insulating member.

The image forming apparatus of the present invention will be described below based on Examples 1 to 4 shown in FIGS.
FIG. 1 is a cross-sectional view schematically showing an image forming apparatus in which the present invention is implemented, and is an example in the case where the image forming apparatus is a copying machine.
The copying machine according to the first embodiment includes a copying machine body 1, a contact glass 2, an automatic document feeder 3, a halogen lamp 4, a reflecting mirror 5, a lens 6, a CCD image sensor 7, an image processing processor unit 8, a paper feed tray 10, Recording paper 11, pickup roll 12, transport roll 13, laser exposure unit (ROS unit) 14, charging device 15, photosensitive drum (electrostatic latent image carrier) 16, (full-color revolver type) developing device 17, drum cleaning device 18, a transfer belt 20, a recording paper transport device 21, a fixing device 22, a fixing housing 23, a fixing roll 24, a pressure roll 25, a paper discharge roll 26, a paper discharge tray 27, a cooling fan 28, and the like.

  As described above, the copying machine according to the first embodiment includes the copying machine main body 1 and the automatic document feeder 3 provided to cover the contact glass 2 installed on the upper surface of the copying machine main body 1 so as to be freely opened and closed. ing. The copying machine main body 1 includes an image reading unit that reads an image or a character of a fixed document placed on the contact glass 2 by the automatic document feeder 3 and converts it into an image signal. An image forming unit that forms a visible image on a recording sheet (recording material, recording sheet, transfer sheet, recording medium,...) Based on an image signal, and a sheet feeding unit that supplies the recording sheet to the image forming unit And are provided.

  The document reading unit forms an image on an image sensor 7 such as a CCD that receives reflected light of a moving or fixed document illuminated by a light source such as a halogen lamp 4 through a lens 6 and reads an optical image as an electrical signal. . The image processing unit 8 is configured to perform predetermined image processing on information obtained by the image sensor 7.

  The paper feeding unit is provided at the lower part of the copying machine main body 1, and the paper feeding tray 10 accommodates the recording paper 11 by size or by recording paper type. The recording paper 11 is fed from one of these paper feed trays 10 by a pickup roll 12 to the transport roll 13 through the paper transport path one by one. FIG. 1 shows an example of one type of paper size.

  The image forming unit is charged by a laser exposure unit (ROS unit) 14 that emits a laser beam modulated by an image signal from the image processing processor unit 8 and a charging device 15 including a corona discharge device. A photosensitive drum 16 as an electrostatic latent image carrier exposed by a laser beam from the toner and a developer such as toner (hereinafter referred to as toner) contained in the cartridge by a developing device 17 such as a full color revolver type. The electrostatic latent image formed on the photosensitive drum 16 by laser beam exposure is visualized as an image, that is, developed on the photosensitive drum 16 by being carried and transferred to the photosensitive drum 16. The transferred image is sent out from the sheet feeding unit, and the posture and the conveyance timing are matched by the conveyance roll 13 and sent to the photosensitive drum 16. A transfer device including a transfer belt 20 to be transferred to the recording paper 11, a fixing device 22 for fixing the unfixed image transferred to the recording paper 11 by the transfer device to the recording paper 11, and the photosensitive drum 16 after transfer. And a drum cleaning device 18 for collecting the toner remaining on the surface.

Since the developing device 17 stirs a certain amount of toner and carrier inside, a torque is required for stirring, and the internal temperature rises due to frictional heat. Further, the photosensitive drum 16 is charged to about 1 kV by corona discharge by the charging device 15, but the ambient temperature rises due to collision of ions generated by dielectric breakdown of air, and thus cooling is necessary. These heats are dissipated in the airflow formed by the cooling fan 28 provided in the copying machine main body 1, and the exhaust heat is collected in one place and discharged outside the copying machine main body 1.
The drum cleaning device 18 includes a brush cleaner that removes residual toner (not shown) on the photosensitive drum 16 and a recovery unit that recovers the removed residual toner.

  The fixing device 22 includes a fixing casing 23 and a pair of heating rolls arranged in the fixing casing 23. The fixing roll 24 constituting one of the rolls includes a heat source such as a halogen lamp and a temperature sensor therein. The surface of the fixing roll 24 is heated and controlled to a temperature necessary for fixing an unfixed image, for example, about 150 ° C. The pressure roll 25 constituting the other roll is composed of a heating roll having a heat source such as a halogen lamp and a temperature sensor inside, and the surface temperature of the pressure roll 25 is controlled to a temperature required for fixing. It arrange | positions so that it may press-contact with the roll 24 with a suitable pressure.

  A nip portion having a predetermined nip width is formed between the fixing roll 24 and the pressure roll 25. The recording paper 11 is heated and pressurized by passing through the nip portion, the unfixed image transferred to the recording paper is fixed, and the fixed recording paper 11 is discharged by the paper discharge roll 26. The paper is discharged to the paper tray 27. At this time, the recording paper 11 is heated by heat fixing, and peripheral devices such as the paper discharge roll 26 and the paper discharge tray 27 are also heated and stored by heat from the recording paper. In the copying machine main body 1, the fixing device 22 corresponds to a device having a heat source having a relatively high temperature.

FIG. 2 is a cross-sectional view schematically illustrating the image forming apparatus according to the first exemplary embodiment.
As in FIG. 1, a copying machine as an example of the image forming apparatus is an automatic document feeder provided so as to cover the copying machine main body 1 and the contact glass 2 installed on the upper surface of the copying machine main body 1 so as to be freely opened and closed. Device 3. In particular, in the present embodiment, the fixing casing 23 of the fixing device 22 is formed of a heat insulating member that is a single layer formed by laminating a metal plate and a resin layer made of a polymer material.

FIG. 3 is a cross-sectional view of the main part showing the configuration of the heat insulating member forming the fixing housing.
The heat insulating member forming the fixing housing 23 is spray coated with polyimide varnish (model number SN-20 of Shin Nippon Rika Co., Ltd.) on a rolled steel plate 31 having a thickness of 0.5 mm, and then at 200 ° C. under atmospheric pressure at 10 ° C. It consists of the laminated board which made the polyimide resin layer 32 20-micrometer-thick by heating for a minute (baking) and blowing off the solvent. The laminates were laminated with the polyimide resin surfaces facing inside to form a heat insulating member. That is, this heat insulating member has a laminated structure of rolled steel sheet / polyimide resin / polyimide resin / rolled steel sheet.

  The fixing housing 23 of the fixing device 22 is composed of upper and lower covers and front, back, left, and right side plates, and the heat insulating member having the above-described laminated structure is processed into a shape and dimensions that function as the fixing housing 23 of the fixing device 22. 2, p-type and n-type thermoelectric semiconductor elements 42, 43 made of an alloy such as Bi, Te, Sb, etc. are formed on an alumina ceramic 41 as shown in FIG. The thermoelectric conversion device 40 electrically connected in series via the electrode 44 was attached via silicone grease (not shown) having good heat conduction characteristics. An aluminum heat block 46 was connected to the heat radiation side of the thermoelectric converter 40.

FIG. 4 is a diagram illustrating a connection structure of a heat block, a heat pipe, and a heat sink.
To the heat block 46, two endothermic sides 47a of a stainless steel heat pipe 47 of SUS304, a diameter of 3.0 mmφ, and a hydraulic fluid are inserted and connected. The heat radiating side 47b of the heat pipe 47 was connected to an aluminum heat sink 48 having cooling fins 49 installed on the copying machine main body 1 side.

  In the heat insulating member used in the fixing housing 23 of the first embodiment, the thickness of the polyimide resin layer 32 is 20 μm. However, the thickness is not limited to this, and a substance having a lower thermal conductivity than metal is present. The thickness is preferably in the range of 1 μm to 1 mm, and the thickness of the polyimide resin layer 32 is more preferably 10 μm to 100 μm in consideration of the application cost of the polyimide varnish, the ease of processing of the plate after applying the polyimide varnish, and the like. .

In addition, the heat insulating member used in the fixing housing 23 of Example 1 has a structure in which two laminated plates are laminated, but may have a structure in which four sheets are laminated or a laminated structure in which four or more are laminated. Considering the manufacturing cost, 10 sheets or less are desirable. Further, even if a polyimide resin layer is formed and laminated on a film having a metal plate thickness of 0.1 mm or less, the same effect can be obtained, and the thickness of the metal plate made of the rolled steel plate 31 and the thickness of the polyimide resin layer 32 are: It is not limited to the thickness of Example 1, but is characterized in that a substance having a lower thermal conductivity than the metal plate is formed on the metal plate.

  In addition, the heat insulating member used in the fixing housing 23 of the first embodiment uses p-type and n-type thermoelectric semiconductor elements 42 and 43 made of an alloy such as Se, Te, and Sb. However, it is desirable to use a thermoelectric conversion material having the highest efficiency in the temperature range to be used. Further, the hydraulic fluid of the heat pipe 47 is not limited to water, but may be naphthalene, ethanol or the like. Moreover, the heat block 46 and the heat sink 48 may be a metal plate including a metal having good thermal conductivity, such as copper, in addition to aluminum, or iron plated with Ni, Cr or the like.

  In order to set the surface temperature of the fixing roll 24 and the pressure roll 25 of the fixing device 22 to a temperature necessary for fixing, for example, 150 ° C., the fixing roll 24 and the pressure roll 25 are heated with a halogen lamp, and each roll is heated with a thermistor. The surface temperature is detected and temperature control is performed. As described above, the heat transferred from the surface of the fixing roll 24 and the pressure roll 25 to the inner surface of the fixing housing 23 or heat is absorbed by the metal plate on the inner surface, but the thermal conductivity is small. Since there is the polyimide resin layer 32, it is possible to reduce the movement of heat to the outside. In addition, when the temperature outside the fixing housing 23 rises due to heat conduction in the laminated plate and a temperature difference occurs in the thermoelectric conversion device 40, a thermoelectromotive force is generated in the thermoelectric conversion device 40 due to this temperature difference, and the electric Energy is generated. So-called thermoelectric conversion is performed. Part of the radiant heat is reflected and confined inside the fixing housing, and the difference between the temperatures of the fixing roll 24 and the pressure roll 25 is reduced. Thereby, the amount of heat radiated from the surfaces of the fixing roll 24 and the pressure roll 25 is reduced, and the power consumption of the halogen lamp is reduced.

  In addition, the thermoelectrically converted electrical energy can be used as driving power for a low-power device in an image forming apparatus such as a display device or various sensors, and when converting exhaust heat to electric power, There is no need to supply energy to the thermoelectric converter 40 from the outside, and since there is no drive part, it can be used without maintenance.

FIG. 5 is a cross-sectional view of a main part showing a configuration of a heat insulating member forming a fixing housing of the image forming apparatus according to the second embodiment.
The heat insulating member constituting the fixing housing 23 of the fixing device 22 has a thickness of 30 μm or less with a polyimide varnish (model number SN-20 of Shin Nippon Rika Co., Ltd.) on a rolled steel plate 31 having a thickness of 0.5 mm. After spraying with a foaming agent, spraying an appropriate amount of 50 μmφ alumina ceramic balls 33 onto one polyimide resin layer 32, and then laminating the polyimide resin surfaces of the heat insulating member together, As temporarily fixed. The configuration of the laminate is rolled steel plate / polyimide resin / polyimide resin / rolled steel plate. Then, it heated at 200 degreeC under atmospheric pressure for 10 minutes (baking), the solvent was skipped, and it was set as the polyimide resin layer 32 about 50 micrometers thick including an air layer. Here, the surface of the rolled steel sheet 31 that is the inner surface of the fixing housing 23 is mechanically polished so as to be a mirror surface.

The fixing housing 23 of the fixing device 22 is composed of upper and lower covers and front, rear, left and right side plates as in the fixing housing of Example 1, and the laminated plate is bent and punched into dimensions that function as the housing of the fixing device. 2, p-type and n-type thermoelectric semiconductor elements made of an alloy such as Bi, Te, Sb, etc. on alumina ceramics on the upper surface, lower left and right surfaces in FIG. The thermoelectric conversion device 40 joined in series with the resin was attached via silicone grease having good heat conduction characteristics. An aluminum heat block 46 was thermally connected to the heat radiation side of the thermoelectric converter 40.

  Furthermore, two stainless steel heat pipes 47 made of SUS304 and having a diameter of 3.0 mmφ and hydraulic fluid of water were inserted into the heat block 46 and thermally connected. The heat radiating side of the heat pipe 47 was connected to an aluminum heat sink 48 installed on the copier body side. As described above, radiation from the surface of the fixing roll 24 and the pressure roll 25 to the inner surface of the casing or heat transported by air is partially absorbed by the metal plate on the inner surface, but includes bubbles 34 having a low thermal conductivity. Since there is the polyimide resin layer 32, it is possible to reduce heat transfer to the outside and reduce the power consumption of the halogen lamp.

  In addition, the thermoelectrically converted electrical energy can be used as driving power for a low-power device in an image forming apparatus such as a display device or various sensors, and when converting exhaust heat to electric power, There is no need to supply energy to the thermoelectric converter from the outside, and since there is no drive part, it can be used without maintenance.

  In the heat insulating member used in the image forming apparatus of Example 2, the thickness of the polyimide resin layer 32 is 20 μm. However, the thickness is not limited to this, and a substance having a thermal conductivity smaller than that of a metal is interposed. The thickness is preferably in the range of 1 μm to 1 mm, and the thickness of the polyimide resin layer is more preferably 10 μm to 100 μm in consideration of the coating cost of the polyimide varnish, the processability of the plate after applying the polyimide varnish, and the like. . Moreover, although it is set as the structure which laminated | stacked two sheets of laminated boards, although it may be 3 layers or more, it may be the laminated structure more than that, but if manufacturing cost is considered, 10 layers or less are desirable.

FIG. 6 is a principal cross-sectional view showing a configuration of a heat insulating member that forms a fixing housing of the image forming apparatus of Embodiment 3, and FIG. 7 is a cross-sectional view showing an end structure of the fixing housing.
The heat insulating member forming the fixing housing 23 of Example 3 is arranged by adhering 100 μmφ alumina balls 33 at a density of 3 to 5 pieces / 100 mm ^{2 on} the surface of a rolled steel plate 31 having a thickness of 0.5 mm, and this surface is bonded to this surface. A rolled steel plate 31 having a plate thickness of 0.5 mm was laminated. The laminate is press-bended and punched according to the drawing specifications, and then the end face is welded 36 under reduced pressure. As a result, the gap between the rolled steel plates 31 and 31 can be in a reduced pressure state close to vacuum, and a heat insulating member with low thermal conductivity can be obtained.

The fixing casing 23 was configured using the upper and lower plates and the left and right plates thus processed. Various parts are attached to the inside of the upper and lower plates of the fixing housing 23 by using screws or the like directly on the parts previously attached by spot welding. Further, the rotating parts such as the main fixing roller 24 and the pressure roller 25 attached to the left and right side plates were welded under reduced pressure on the end surfaces of the plates processed into a shape corresponding to the surface excluding the rotation transmitting portion. Similarly, various parts are attached to the inside of the left and right plates of the fixing housing 23 by directly using screws or the like to parts previously attached by spot welding.

  On the outside of the fixing housing 23, similarly to the fixing device of the first embodiment shown in FIG. 2, p-type and n-type thermoelectric semiconductor elements made of an alloy such as Bi, Te, Sb on the upper surface and the left and right surfaces in the drawing. A thermoelectric conversion device 40 in which 42 and 43 are electrically connected in series was attached via a silicone grease having good heat conduction characteristics (not shown). An aluminum heat block 46 was thermally connected to the heat radiation side of the thermoelectric converter 40. Further, two stainless steel heat pipes 47 made of SUS304, a diameter of 3.0 mmφ and a hydraulic fluid were inserted into the heat block 46 and thermally connected. The heat radiating side of the heat pipe 47 was connected to an aluminum heat sink 48 installed on the copier body side. As described above, in the laminated plate constituting the fixing housing 23, the heat radiated from the surfaces of the fixing roll 24 and the pressure roll 25 is reflected by the surface of the laminated plate, partially absorbed, heated, and the temperature rises. However, by providing the reduced pressure or vacuum layer 35 having a low thermal conductivity, heat transfer to the outside can be reduced. Even when the temperature of the laminated plate rises, a thermoelectromotive force is generated due to a temperature difference between the heat absorption side and the cooling side of the thermoelectric conversion device 40. The thermoelectromotive force is stored in the power storage device through the power lead-out line and reused as electric energy.

  Since a part of the radiant heat is reflected and confined in the fixing housing 23, the amount of heat radiated from the surfaces of the fixing roll 24 and the pressure roll 25 is reduced, and the power consumption of the halogen lamp can be reduced. In addition, the thermoelectrically converted electrical energy can be used as driving power for a low power device in an image forming apparatus such as a display device, various sensors, and the like. There is no need to supply energy to the conversion device from the outside, and since there is no drive unit, it can be used without maintenance.

FIG. 8 is a cross-sectional view schematically illustrating the image forming apparatus according to the fourth embodiment.
The image forming apparatus of Example 4 is an example in which the generated electric power is connected to the output side of the thermoelectric conversion device 40. The storage means is a rechargeable battery (secondary battery), and the image forming apparatus Is installed in the copying machine main body 1.
Specifically, the lithium ion secondary battery 51 was connected to each output side of the thermoelectric conversion device 40 installed around the fixing device 22 via the power extraction line 50. The heat leaked from the fixing means 22 was converted into electric power in each thermoelectric conversion device 40 shown in Examples 1 to 3, and the lithium ion secondary battery 51 was charged. Using the stored electric power, the display element of the operation panel in the copying machine main body 1 can be driven.

  In addition, secondary batteries such as metallic lithium secondary batteries, alkaline storage batteries, lead acid batteries, lithium polymer batteries, and large-capacity capacitors may be used, and conversion from waste heat is possible by installing these power storage devices. The stored power can be used as drive power for display devices and electronic devices of image forming apparatuses, as drive power for other electrical devices, and for storage batteries. Various usages are possible by changing the capacity.

1 is a cross-sectional view schematically showing an image forming apparatus in which the present invention is implemented, and is an example when the image forming apparatus is a copying machine. 1 is a cross-sectional view schematically illustrating an image forming apparatus according to a first exemplary embodiment. FIG. 3 is a cross-sectional view of a main part illustrating a configuration of a heat insulating member that forms a fixing housing of the image forming apparatus according to the first exemplary embodiment. It is a figure which shows the connection structure of a heat block, a heat pipe, and a heat sink. FIG. 6 is a cross-sectional view of a main part illustrating a configuration of a heat insulating member that forms a fixing housing of an image forming apparatus according to a second exemplary embodiment. FIG. 6 is a cross-sectional view of a main part illustrating a configuration of a heat insulating member that forms a fixing housing of an image forming apparatus according to a third exemplary embodiment. 6 is a cross-sectional view illustrating an end structure in a fixing housing of an image forming apparatus according to Embodiment 3. FIG. FIG. 10 is a cross-sectional view schematically illustrating an image forming apparatus according to a fourth embodiment.

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 ... Copier main body, 2 ... Contact glass, 3 ... Automatic document feeder, 4 ... Halogen lamp, 7 ... Image sensor, 8 ... Image processing processor part, 10 ... Paper feed tray, 11 ... Recording paper, 14 ... Laser exposure 15, charging device, 16, photosensitive drum, 17, developing device, 18, drum cleaning device, 20, transfer belt, 22, fixing device, 23, fixing housing, 24, fixing roll, 25, pressure roll 27 ... discharge tray, 28 ... cooling fan, 31 ... rolled steel plate, 32 ... polyimide resin layer, 33 ... alumina ball, 34 ... bubbles, 35 ... depressurized or vacuum layer, 40 ... thermoelectric converter, 41 ... alumina ceramics, 42 ... p-type thermoelectric semiconductor element, 43 ... n-type thermoelectric semiconductor element, 44, 45 ... electrode, 46 ... heat block, 47 ... heat pipe, 48 ... heat sink, 49 ... cold Fins, 51 ... lithium ion secondary battery.

Claims (5)

An image is fixed by the sheet feeding and conveying means for feeding the recording paper, the unfixed image forming means for forming an unfixed image on the recording paper, the fixing means for fixing the unfixed image by heat, and the fixing means. In the image forming apparatus provided with the paper discharge conveying means for discharging the recording paper, the fixing means is surrounded by a heat insulating member, and the heat insulating member is a set of metals in which a polymer material resin layer is formed on the metal. An image forming apparatus characterized in that the heat insulator made of a resin layer has a multilayer structure in which the resin layers are bonded to each other .   The image forming apparatus according to claim 1, wherein the fixing unit includes a fixing roller having a heating element and a pressure roller. The image forming apparatus according to claim 1, wherein the heat insulating member has a thermoelectric conversion element on a surface thereof . The image forming apparatus according to claim 3 , wherein the thermoelectric conversion element has a heat sink in a heat radiating portion thereof. The image forming apparatus according to claim 3 or 4, characterized in that it has a power storage device storing electric power converted thermoelectric by the thermoelectric converter.