Patent Publication Number: US-11644775-B2

Title: Heating device with heating roller having resistance heat-generating layer and heating-target using apparatus

Description:
CROSS-REFERENCE TO RELATED APPLICATIONS 
     This application is based on and claims priority under 35 USC 119 from Japanese Patent Application No. 2021-085908 filed May 21, 2021. 
     BACKGROUND 
     (i) Technical Field 
     The present disclosure relates to a heating device and a heating-target using apparatus. 
     (ii) Related Art 
     Japanese Unexamined Patent Application Publication No. 2017-10020 (claim 25, FIG. 1 to FIG. 3, and so forth) describes a fixing device that fixes an image onto a recording material. The fixing device includes a heat rotating body that has a heat generating layer and a pressing member that forms a nip part with the heat rotating body. The heat rotating body has a plurality of low-resistance layers formed on a region of the heat generating layer in which the recording material is transported, the low-resistance layers being arranged in such a manner as to be spaced apart from each other in the longitudinal direction so that they do not come into contact with each other. The plurality of low-resistance layers are each a layer that has a volume resistance value lower than that of the heat generating layer and extends in a circumferential direction of the heat generating layer. 
     Japanese Unexamined Patent Application Publication No. 2013-142834 (claim 1, FIG. 1, and so forth) describes a heat-generating fixing roller having a resistance heat-generating element that is provided on the inner peripheral surface of a cylindrical core bar with an electrical insulating layer interposed therebetween. The electrical insulating layer is made of a water-repellent resin, and the core bar, the electrical insulating layer, and the resistance heat-generating element are arranged in such a manner as to be in close contact with one another. 
     SUMMARY 
     Aspects of non-limiting embodiments of the present disclosure relate to providing a heating device and a heating-target using apparatus that are capable of suppressing asymmetric and uneven distribution of temperature in a heating roller, which has a resistance heat-generating layer, in an axial direction of the heating roller compared with the case where a power receiving component that receives a rotational power to be transmitted to the heating roller is mounted on the heating roller or the case where a complementary component that has a heat capacity approximately equal to that of the power receiving component is not mounted on the heating roller. 
     Aspects of certain non-limiting embodiments of the present disclosure address the above advantages and/or other advantages not described above. However, aspects of the non-limiting embodiments are not required to address the advantages described above, and aspects of the non-limiting embodiments of the present disclosure may not address advantages described above. 
     According to an aspect of the present disclosure, there is provided a heating device including a heating roller having a resistance heat-generating layer that generates heat by passage of a current through the resistance heat-generating layer, a support member that supports a treatment portion in which a heating treatment is performed, a belt that is stretched between at least the heating roller and the support member and that rotates, and a pressure rotating body that rotates in such a manner as to press a sheet-shaped heating target that is an object to be subjected to a heating treatment against the treatment portion including an outer peripheral surface portion of the belt that is supported by the support member and in such a manner as to cause the heating target to pass through the treatment portion, wherein the heating roller is not equipped with a power receiving component configured to receive a rotational power that is transmitted. 
    
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
       Exemplary embodiments of the present disclosure will be described in detail based on the following figures, wherein: 
         FIG.  1    is a schematic diagram of an image forming apparatus according to a first exemplary embodiment, which is an example of a heating-target using apparatus; 
         FIG.  2    is a schematic diagram of a fixing device according to the first exemplary embodiment, which is an example of a heating device; 
         FIG.  3    is a schematic diagram illustrating a portion of the fixing device illustrated in  FIG.  2   ; 
         FIG.  4 A  and  FIG.  4 B  are respectively a schematic cross-sectional view of a heating roller and a schematic cross-sectional view taken along line IVB-IVB of  FIG.  4 A ; 
         FIG.  5 A  and  FIG.  5 B  are respectively a schematic diagram illustrating a portion of the heating roller and a schematic diagram illustrating a heating roller for comparison; 
         FIG.  6    is a schematic diagram of a fixing device according to a second exemplary embodiment, which is another example of the heating device; and 
         FIG.  7    is a schematic diagram illustrating a heating device according to a third exemplary embodiment and a heating-and-drying apparatus according to the third exemplary embodiment, which is another example of a heating-target using apparatus. 
     
    
    
     DETAILED DESCRIPTION 
     Exemplary embodiments of the present disclosure will be described below with reference to the drawings. 
     First Exemplary Embodiment 
       FIG.  1    illustrates an image forming apparatus  1 A according to the first exemplary embodiment, which is an example of a heating-target using apparatus  1 .  FIG.  2    illustrates a fixing device  5 A according to the first exemplary embodiment, which is an example of a heating device  5 . 
     The heating-target using apparatus  1  is an apparatus that uses a sheet-shaped object  9  that is to be heated (hereinafter referred to as “heating target  9 ”). The heating device  5  is a device that at least heats the sheet-shaped heating target  9 . 
     In the following description, the direction indicated by arrow X, the direction indicated by arrow Y, and the direction indicated by arrow Z in the drawings respectively correspond to a width direction of the apparatus, a height direction of the apparatus, and a depth direction of the apparatus that is perpendicular to both the width direction and the height direction. In the drawings, a circle mark at the intersection of arrow X and arrow Z indicates that arrow Z corresponding to the depth direction of the apparatus points in a downward direction perpendicular to the plane in each of the drawings. 
     &lt;Heating-Target Using Apparatus&gt; 
     The image forming apparatus  1 A, which is an example of the heating-target using apparatus  1 , forms an image by heating one of recording media  9 A on which an image has been formed with powder developer. Each of the recording media  9 A is an example of the sheet-shaped heating target  9 . 
     As illustrated in  FIG.  1   , the image forming apparatus  1 A includes a housing  10  having a desired external shape, and an image forming device  2 , a medium supply device  4 , a medium transport device  45 , a fixing device  5 A, and so forth are arranged in the internal space of the housing  10 . In  FIG.  1   , a transport path along which the recording media  9 A are transported by the medium transport device  45  in the housing  10  is indicated by a one-dot chain line. 
     The image forming device  2  is a device that forms a toner image by using a toner, which functions as a developer, and transfers the toner image onto one of the recording media  9 A. The image forming device  2  is configured as, for example, a device that employs an image forming system such as an electrophotographic system, and in the image forming device  2 , units such as a charging unit  22 , an exposure unit  23 , a developing unit  24 , a transfer unit  25 , and a cleaning unit  26  are arranged around a photoconductor drum  21  that rotates in the direction indicated by arrow A. 
     The photoconductor drum  21  is an example of an image holding unit and is a drum-shaped photoconductor having a photosensitive layer that serves as an image forming surface and as an image holding surface. The charging unit  22  is a unit that charges the outer peripheral surface (the image forming surface) of the photoconductor drum  21  to a required surface potential. For example, the charging unit  22  includes a charging member that has, for example, a roll-like shape, and the charging member is brought into contact with the outer peripheral surface (the image forming surface) of the photoconductor drum  21  and is supplied with a charging current. 
     The exposure unit  23  is a unit that exposes the outer peripheral surface of the photoconductor drum  21 , which has been charged, to light on the basis of image information so as to form an electrostatic latent image. The exposure unit  23  operates in response to receiving an image signal that is generated as a result of an image processing unit or the like (not illustrated) performing a required processing operation on image information input from the outside. The image information is, for example, information relating to an image to be formed such as a character, a figure, a photograph, or a pattern. The developing unit  24  is a unit that develops an electrostatic latent image formed on the outer peripheral surface of the photoconductor drum  21  into a visible monochromatic color toner image with a developer (a toner) of a corresponding predetermined color (e.g., black). 
     The transfer unit  25  is a unit that electrostatically transfers a toner image formed on the outer peripheral surface of the photoconductor drum  21  onto one of the recording media  9 A. The transfer unit  25  includes a transfer member that has, for example, a roll-like shape, and the transfer member is brought into contact with the outer peripheral surface of the photoconductor drum  21  and is supplied with a transfer current. The cleaning unit  26  is a unit that cleans the outer peripheral surface of the photoconductor drum  21  by removing unwanted substances such as undesirable toner and paper dust deposited on the outer peripheral surface of the photoconductor drum  21 . 
     In the image forming device  2 , a portion where the photoconductor drum  21  and the transfer unit  25  face each other corresponds to a transfer position TP at which transfer of a toner image is performed. 
     The medium supply device  4  is a device that accommodates and sends out the recording media  9 A each of which is to be supplied to the transfer position TP in the image forming device  2 . The medium supply device  4  includes units such as one or more accommodating units  41  in which the recording media  9 A are accommodated and one or more delivery units  43  that send out the recording media  9 A one by one. 
     The recording media  9 A may be sheet-shaped recording media that are capable of being transported by the medium transport device  45  in the housing  10  and onto which toner images are transferable and thermally fixable, and the material, the form, and so forth of the recording media  9 A are not particularly limited. In the image forming apparatus  1 A, a recording medium such as a normal sheet, a coated sheet, a film, a piece of foil, a piece of sheet-shaped cloth that is cut to have a predetermined size or a recording medium such as an envelope is used as each of the recording media  9 A. 
     The medium transport device  45  is a device that is an example of a transport unit configured to transport the heating target  9  such as one of the recording media  9 A, and in the image forming apparatus  1 A, the medium transport device  45  is configured as a device that transports each of the recording media  9 A to a predetermined position in the housing  10 . 
     The medium transport device  45  is disposed in the housing  10  in such a manner that a supply path along which the recording media  9 A are transported from the medium supply device  4  to the transfer position TP in the image forming device  2 , a relay path along which the recording media  9 A are transported from the transfer position TP in the image forming device  2  to the fixing device  5 A, an ejection path along which the recording media  9 A are transported from the fixing device  5 A to an ejection port  12 , which is formed in, for example, a side surface portion of the housing  10 , and so forth are formed. More specifically, the medium transport device  45  is formed by arranging a required number of pairs of transport rollers  46  ( 46   a  to  46   d ) and a required number of guide path members  47  at predetermined positions. The pairs of transport rollers  46  are each configured to transport each of the recording media  9 A by nipping the recording medium  9 A therebetween, and the guide path members  47  form a transport space or the like that guides the recording media  9 A destination. 
     The fixing device  5 A, which is an example of the heating device  5 , is a device that performs heat and pressure treatments in order to fix a toner image, which is an unfixed image that has been transferred to one of the recording media  9 A at the transfer position TP in the image forming device  2 , onto the recording medium  9 A. The fixing device  5 A is formed by arranging units such as a heat rotating body  51  and a pressure rotating body  61  in an internal space of a housing  50  that has an introduction port  50   a  and an ejection port  50   b  for the recording media  9 A. 
     In addition, in the fixing device  5 A, as illustrated in  FIG.  1    and  FIG.  2   , the heat rotating body  51  and the pressure rotating body  61  are arranged so as to rotate while being in contact with each other. The portion in which the heat rotating body  51  and the pressure rotating body  61  are in contact with each other is configured as a fixing treatment portion FN in which heat and pressure are applied to one of the recording media  9 A and a toner image that pass through the fixing treatment portion FN. 
     Details of the fixing device  5 A will be described later. 
     In the image forming apparatus  1 A, for example, image formation is performed in the following manner. 
     In the image forming apparatus  1 A, in response to a control unit (not illustrated) receiving a command for an image forming operation, in the image forming device  2 , a charging operation, an exposure operation, a developing operation, and a transfer operation are performed. Meanwhile, the medium supply device  4  sends out a desired one of the recording media  9 A, and the recording medium  9 A is transported along the supply path of the medium transport device  45  and fed to the transfer position TP. 
     As a result, a toner image is formed on the photoconductor drum  21  in accordance with image information, and the toner image is transferred onto the recording medium  9 A fed to the transfer position TP from the medium supply device  4  by the medium transport device  45 . In this case, the recording medium  9 A to which the toner image has been transferred is separated from the photoconductor drum  21 , which is rotating, while being nipped between the photoconductor drum  21  and the transfer unit  25  and then transported toward the heating device  5  along the relay path of the medium transport device  45 . 
     Subsequently, in the fixing device  5 A of the image forming apparatus  1 A, when one of the recording media  9 A to which toner images  92  have been transferred is introduced into the fixing treatment portion FN, in which the heat rotating body  51  and the pressure rotating body  61  are in contact with each other, so as to pass through the fixing treatment portion FN as illustrated in  FIG.  2   , a fixing operation is performed. As a result, in the fixing device  5 A, the unfixed toner images  92  on the recording medium  9 A are heated under pressure, and the toner images  92  melt and are fixed onto the recording medium  9 A. 
     The recording medium  9 A to which the toner images  92  have been fixed is ejected from the housing  50  while being nipped between the heat rotating body  51  and the pressure rotating body  61  in the fixing device  5 A and then transported along the ejection path of the medium transport device  45  to the ejection port  12 . Finally, the recording medium  9 A is sent out by the transport rollers  46   d  and accommodated in an ejected-sheet-accommodating unit (not illustrated) that is formed in a portion of the housing  10 . 
     By performing the above series of operations, a basic image forming operation for forming a monochromatic image onto a surface of one of the recording media  9 A is completed. 
     &lt;Heating Device&gt; 
     The fixing device  5 A will now be described in detail. 
     As illustrated in  FIG.  2   ,  FIG.  3   , and the like, the fixing device  5 A according to the first exemplary embodiment uses a belt-nip-type heating unit  52  as the above-mentioned heat rotating body  51  and a pressure roller  62  having a roll-like shape as the above-mentioned pressure rotating body  61 . 
     The heating unit  52  includes a heating roller  53 , a support member  54 , a fixing belt  55 , an adjustment support roller  56 , and so forth that are integrated with one another. 
     As illustrated in  FIG.  4   , the heating roller  53  is a roller body having a multilayer structure in which an electrical insulating layer  532 , a resistance heat-generating layer  533  that generates heat by passage of a current therethrough, and a surface layer  534  are provided in this order on the outer peripheral surface of a cylindrical roller base member  531 . 
     The roller base member  531  is a cylindrical body that is made of a metal material such as aluminum or iron and that has a thickness of about 0.2 to about 1.0 mm. The electrical insulating layer  532  is an insulating film made of a material such as a polyimide or polyether ether ketone (PEEK) that has an insulating property. 
     The resistance heat-generating layer  533  is a layer that generates heat by passage of a current therethrough and is a layer or a film that is made of a material such as silver palladium, gold palladium, or a mixture of carbon and a metal filler. The resistance heat-generating layer  533  is formed by, for example, a die-casting application technique from the standpoint of making the resistance heat-generating layer  533  to have a uniform layer thickness or the like. In addition, power is supplied to the resistance heat-generating layer  533  via electrode layers  535  formed at the two ends of the roller in the axial direction of the roller. 
     The surface layer  534  is a layer that has favorable thermal conductivity and that is capable of protecting the resistance heat-generating layer  533 . In addition, the surface layer  534  may be a layer having tackiness for transmitting a rotational power to the fixing belt  55  and wettability with respect to a lubricating material, which will be described later, and from this standpoint, the surface layer  534  is made of a material having low releasability (e.g., a polyimide, polyether ether ketone (PEEK), or the like). 
     As illustrated in  FIG.  3   , the two end portions of the roller base member  531  are attached to upper side surface portions of the housing  50  with bearings  65  interposed therebetween such that the heating roller  53  is rotatable. 
     In addition, in the heating roller  53 , power supply connectors  58 A and  58 B are attached to shaft portions that are formed of the two end portions of the roller base member  531  projecting toward the outside of the bearings  65 . The power supply connectors  58 A and  58 B include power supply rings (not illustrated) that are arranged inside cylindrical insulating covers, and these power supply rings are electrically connected to the electrode layers  535 , which are formed on the two end portions of the heating roller  53 . The power supply connectors  58 A and  58 B are connected to a power supply unit  17 , and when heating is required, a required current is supplied to the power supply connectors  58 A and  58 B from the power supply unit  17 . 
     The fixing belt  55  is heated by the heating roller  53 , and in the fixing treatment portion FN, the fixing belt  55  comes into contact with a surface of one of the recording media  9 A to which the toner images  92  have been transferred and heats the surface. As the fixing belt  55 , a flexible, heat-resistant endless belt for heat conduction is used, and an example of such a belt is a belt having a layered structure in which an elastic layer made of an elastic material, such as a silicone rubber, and a release layer made of a resin material, such as polytetrafluoroethylene (PTFE), are formed in this order on the outer peripheral surface of a cylindrical belt base member made of a synthetic resin, such as a polyimide or polyamide. 
     In addition, as illustrated in  FIG.  2   , the fixing belt  55  rotates in a direction indicated by arrow C while being stretched by the support member  54  and the adjustment support roller  56 . 
     The support member  54  is a member that is disposed in such a manner as to be in contact with the inner peripheral surface of the fixing belt  55  and that supports and forms the fixing treatment portion FN in which the heating treatment is performed. The fixing treatment portion FN is a treatment portion for heating and fixing that is formed at a portion of the outer peripheral surface of the fixing belt  55 , the portion being supported by the support member  54 . The support member  54  is a structure formed of a plate-shaped support that has a hollow structure and that is disposed in such a manner as to extend parallel to the axial direction of the heating roller  53  and a pad member that is attached to a surface portion of the support, the surface portion being in contact with the inner peripheral surface of the fixing belt  55 . 
     In addition, the support member  54  is positioned by fixedly attaching two end portions of the support that protrude from the two ends of the fixing belt  55  to, for example, side surface portions of the housing  50 . 
     The adjustment support roller  56  is a roller that holds the fixing belt  55 , which in the stretched state, in a desired shape by exerting a required tension on the fixing belt  55  and performs adjustment for stabilizing the rotating state of the fixing belt  55 . 
     As illustrated in  FIG.  2   , the heating unit  52  further includes a lubricating-material application unit  57  that applies the lubricating material to the inner peripheral surface of the fixing belt  55  and a temperature sensor  59  that measures the surface temperature of the heating roller  53 . 
     In addition, as illustrated in  FIG.  3   , in the heating unit  52 , a plurality of temperature sensors  59   a  to  59   d  are arranged at predetermined positions (e.g., in opposite end regions and in a central region) in the axial direction of the heating roller  53  so as to measure surface temperatures of the heating roller  53  in a plurality of regions, and the heating unit  52  transmits the measurement results to a control device  15 . The control device  15  controls the output operation or the like of the power supply device  17  so as to adjust the heating state. 
     In contrast, as illustrated in  FIG.  2   , the pressure roller  62  is a roller body having a structure in which an elastic release layer  622  is provided on the outer peripheral surface of a roller base member  621  that has a columnar shape or a cylindrical shape. 
     As illustrated in  FIG.  2   , the pressure roller  62  is attached to lower side surfaces of the housing  50  with bearings  66  interposed therebetween so as to be rotatable at a position where the pressure roller  62  faces the support member  54 , the bearings  66  being attached to shaft portions  623  that protrude from the two ends of the roller base member  621 . In addition, the bearings  66  are attached to the pressure roller  62  in such a manner as to be displaceable in directions toward and away from the support member  54 , and a predetermined pressure in a direction toward the support member  54  is applied to the bearings  66  by urging members (not illustrated) such as springs. As a result, the fixing belt  55  passes through (the pad member of) the support member  54  while being pressed against (the pad member of) the support member  54  with a predetermined pressure. 
     In the fixing device  5 A, when it is time to perform the fixing treatment or the like, the resistance heat-generating layer  533  of the heating roller  53  in the heating unit  52  generates heat by passage of a current therethrough and starts heating the heating roller  53  such that the heating roller  53  is kept at a predetermined temperature. In addition, the pressure roller  62  rotates in a direction indicated by arrow B, and the fixing belt  55  rotates in the direction indicated by arrow C. 
     As a result, the fixing belt  55  rotates in such a manner as to pass through the fixing treatment portion FN while being heated by the heating roller  53 , and the fixing device  5 A becomes capable of performing the fixing treatment. 
     In addition, as illustrated in  FIG.  3   , the fixing device  5 A employs a configuration in which a power receiving component  67  that receives a rotational power that is transmitted at the timing at which the fixing treatment or the like is performed is not mounted on the heating roller  53 . 
     As a result, in the fixing device  5 A, asymmetric and uneven distribution of temperature in the heating roller  53  in the axial direction of the heating roller  53  is suppressed. 
     In contrast, in the case where the power receiving component  67 , a representative example of which is a metal gear  67 A, is attached to one end portion of the heating roller  53  (inn practice, the roller base member  531  or the shaft portions), heat dissipation in the one end portion of the heating roller  53  is accelerated by the influence of the heat capacity of the gear  67 A serving as the power receiving component  67 , and the surface temperature is reduced, and this may sometimes cause asymmetric and uneven distribution of temperature in the heating roller  53  in the axial direction. In other words, in this case, regarding the distribution of the surface temperature of the heating roller  53  in the axial direction when a heat-generating region is heated as a result of the resistance heat-generating layer  533  of the heating roller  53  generating heat, the surface temperature in the heat-generating region near the one end portion to which the power receiving component  67  is attached becomes relatively lower than the surface temperature in the heat-generating region near the other end portion. 
     However, in the fixing device  5 A, the heating roller  53  is not influenced by the heat capacity of the power receiving component  67 , and thus, the above-mentioned asymmetric and uneven distribution of temperature that is generated in the case where the power receiving component  67  is attached to the one end portion of the heating roller  53  is suppressed. 
     In addition, such asymmetric and uneven distribution of temperature may induce asymmetric and uneven fixing, and accordingly, such asymmetric and uneven fixing is also suppressed from being generated. 
     Since the fixing device  5 A employs the above-described configuration for the power receiving component  67 , the gear  67 A serving as the power receiving component  67  is attached to one of the shaft portions  623  of the pressure roller  62  as illustrated in  FIG.  3   . The one shaft portion  623  is located on the far side in the apparatus depth direction Z. 
     A rotational power from a driving device (not illustrated) that is disposed in the housing  10  of the image forming apparatus  1 A is transmitted to the gear  67 A serving as the power receiving component  67 , which is attached to one end portion of the pressure roller  62 , via a final transmission gear  18 . 
     Thus, in the fixing device  5 A, when it is time to perform the fixing treatment or the like, as illustrated in  FIG.  2    as an example, the pressure roller  62  is driven so as to rotate in the direction indicated by arrow B, and a rotational force of the pressure roller  62  is transmitted to the fixing belt  55 , which is in contact with the pressure roller  62  in the fixing treatment portion FN, so that the fixing belt  55  is driven so as to rotate in the direction indicated by arrow C. 
     In addition, in the fixing device  5 A, as illustrated in  FIG.  5 A , the resistance heat-generating layer  533  is provided in such a manner that, in the axial direction of the heating roller  53  (the longitudinal direction), a distance La 1  from one end  533   c  of the resistance heat-generating layer  533  to one end  531   c  of the roller base member  531  and a distance Lb 1  from the other end  533   d  of the resistance heat-generating layer  533  to the other end  531   d  of the roller base member  531  are equal to each other (La 1 =Lb 1 ). 
     As a result, in the fixing device  5 A, compared with a heating roller  530  that is illustrated in  FIG.  5 B  as an example and that has the resistance heat-generating layer  533  provided in such a manner that, in the axial direction of the heating roller  530 , a distance La 2  from the end  533   c  of the resistance heat-generating layer  533  to the end  531   c  of the roller base member  531  and a distance Lb 2  from the end  533   d  of the resistance heat-generating layer  533  to the end  531   d  of the roller base member  531  are different from each other (e.g., La 2 &gt;Lb 2 ), the heat dissipation amount at the two end portions of the roller base member  531 , on each of which the resistance heat-generating layer  533  is not provided, is approximately the same, and thus, this makes it easier to suppress the above-mentioned asymmetric and uneven distribution of temperature in the axial direction of the heating roller  53 . 
     Second Exemplary Embodiment 
       FIG.  6    illustrates a fixing device  5 B according to the second exemplary embodiment, which is another example of the heating device  5 . 
     The fixing device  5 B according to the second exemplary embodiment is different from the fixing device  5 A according to the first exemplary embodiment in that the power receiving component  67  is attached to one end portion of the heating roller  53  and in that a complementary component  70  that has a heat capacity approximately equal to that of the power receiving component  67  is attached to the other end portion of the heating roller  53 . The configuration of the fixing device  5 B excluding the above, is the same as that of the fixing device  5 A. Accordingly, in the following description and the drawings, components that are common to the first exemplary embodiment are denoted by the same reference signs used in the first exemplary embodiment, and descriptions of the components will be omitted unless necessary. 
     As illustrated in  FIG.  6   , in the fixing device  5 B, a gear  67 B that serves as the power receiving component  67  is attached to one end portion of the roller base member  531  that corresponds to one end portion of the heating roller  53  and that is located on the far side. More specifically, the gear  67 B is attached to the far-side end portion of the roller base member  531  in such a manner as to be positioned between one of the bearing  65  and the power supply connector  58 A. 
     A rotational power from a driving device (not illustrated) that is disposed in the housing  10  of the image forming apparatus  1 A is transmitted to the gear  67 B serving as the power receiving component  67 , which is attached to one end of the heating roller  53 , via the final transmission gear  18 . 
     In addition, in the fixing device  5 B, as illustrated in  FIG.  6   , the complementary component  70  having a heat capacity approximately equal to the heat capacity of the gear  67 B is attached to the other end portion of the roller base member  531  that corresponds to the other end portion of the heating roller  53  and that is located on the near side. As the complementary component  70 , a member that is made of the same material and that has the same shape as the power receiving component  67 , such as the gear  67 B, may be used. In addition, similar to the gear  67 B, the complementary component  70  is attached to the near-side end portion of the roller base member  531  in such a manner as to be positioned between one of the bearing  65  and the power supply connector  58 B. 
     In the fixing device  5 B, when it is time to perform the fixing treatment or the like, the resistance heat-generating layer  533  of the heating roller  53  in the heating unit  52  generates heat by passage of a current therethrough and starts heating the heating roller  53  such that the heating roller  53  is kept at a predetermined temperature, and in addition, the heating roller  53  starts rotating in the direction indicated by arrow C, so that the fixing belt  55  also rotates in the direction indicated by arrow C. Then, a rotational force of the fixing belt  55  is transmitted to the pressure roller  62  in the fixing treatment portion FN, and the pressure roller  62  is driven so as to start rotating in the direction indicated by arrow B. 
     As a result, the fixing belt  55  rotates in such a manner as to pass through the fixing treatment portion FN while receiving a rotational driving force from the heating roller  53 A and also being heated by the heating roller  53 A, and the fixing device  5 B becomes capable of performing the fixing treatment. 
     In addition, in the fixing device  5 B, although heat dissipation in the one end portion of the roller base member  531  of the heating roller  53 , to which the gear  67 B serving as the power receiving component  67  is attached, is accelerated by the influence of the heat capacity of the gear  67 B, and the surface temperature is reduced, the complementary component  70  is attached to the other end portion of the roller base member  531 , which corresponds to the other end portion of the heating roller  53 , and thus, heat dissipation in the other end portion is accelerated by the influence of the heat capacity of the complementary component  70 , and the surface temperature is reduced. As a result, uneven distribution of temperature in the axial direction of the heating roller  53  becomes approximately uniform. 
     In addition, as in the fixing device  5 A according to the first exemplary embodiment, in the fixing device  5 B, the resistance heat-generating layer  533  is provided in such a manner that, in the axial direction of the heating roller  53 , the distance La 1  from the end  533   c  of the resistance heat-generating layer  533  to the end  531   c  of the roller base member  531  and the distance Lb 1  from the end  533   d  of the resistance heat-generating layer  533  to the end  531   d  of the roller base member  531  are equal to each other (see  FIG.  5 A ). This makes it easier to suppress the above-mentioned asymmetric and uneven distribution of temperature in the axial direction of the heating roller  53  in the fixing device  5 B for the same reason as in the case of the fixing device  5 A according to the first exemplary embodiment. 
     Thus, in the fixing device  5 B, the above-mentioned asymmetric and uneven distribution of temperature in the axial direction of the heating roller  53  is suppressed, whereas in the case where the complementary component  70  having a heat capacity approximately equal to that of the power receiving component  67  is not attached to the heating roller  53 , the above-mentioned asymmetric and uneven distribution of temperature in the axial direction of the heating roller  53  is not suppressed. 
     In addition, in the fixing device  5 B, although in the case where there is asymmetric and uneven distribution of temperature in the heating roller  53 , the asymmetric and uneven distribution of temperature may induce asymmetric and uneven fixing, such asymmetric and uneven fixing is also suppressed from being generated. 
     Third Exemplary Embodiment 
       FIG.  7    illustrates a heating device  5 C according to the third exemplary embodiment that is another example of the heating device  5  and a heating-and-drying apparatus  1 B according to the third exemplary embodiment that uses the heating device  5 C and that is another example of the heating-target using apparatus  1 . 
     The heating device  5 C according to the third exemplary embodiment is different from the fixing device  5 A according to the first exemplary embodiment and the fixing device  5 B according to the second exemplary embodiment in that the fixing belt  55  is changed to a heating belt  55 B. The configuration of the heating device  5 C excluding the above, is the same as the configuration of the heating device  5 A and the configuration of the fixing device  5 B. Accordingly, in the following description and the drawings, components that are common to these devices are denoted by the same reference signs used in the first exemplary embodiment, and descriptions of the components will be omitted unless necessary. 
     In the heating device  5 C, a belt having favorable thermal conductivity is used as the heating belt  55 B, and for example, a belt that is formed of a cylindrical belt base member made of a synthetic resin such as a polyimide or polyamide is used. Note that, the above-mentioned fixing belt  55  may be used as the heating belt  55 B. 
     In addition, in the heating device  5 C, a portion in which a portion of the heating belt  55 B that is supported by the support member  54  and the pressure roller  62  are pressed into contact with each other is configured as a drying treatment portion DN in which heating and drying treatments are performed. 
     The heating-and-drying apparatus  1 B using the heating device  5 C includes a sheet transport device  45 B that transports a sheet-shaped object  9 B that requires heating and drying as the heating target  9  in such a manner that the sheet-shaped object  9 B is introduced into and passes through the drying treatment portion DN of the heating device  5 C. The sheet transport device  45 B includes pairs of transport rollers  48 , guide members  49 , and so forth. Examples of the sheet-shaped object  9 B include the above-mentioned recording media  9 A. 
     Also in the heating device  5 C, asymmetric and uneven distribution of temperature in the heating roller  53  in the axial direction is suppressed from being generated. Consequently, heating and drying are suppressed from becoming asymmetric and uneven due to such asymmetric and uneven distribution of temperature. 
     Modifications 
     The present disclosure is not limited to the configuration examples that have been described as examples in the above exemplary embodiments, and for example, the present disclosure also includes modifications such as those described below. 
     In the above-described fixing devices  5 A,  5 B, and  5 C, the adjustment support roller  56  of the heating unit  52  does not need to be provided. In addition, for example, a belt-nip-type pressure rotating body may be used as the pressure rotating body  61  instead of the pressure roller  62  having a roll-like shape. Furthermore, the power receiving component  67  may be, for example, a pulley that receives a timing belt for drive transmission. 
     In the first exemplary embodiment and the like, although a configuration example in which the image forming apparatus  1 A forms a monochromatic image has been described, the image forming apparatus  1 A may be an apparatus that forms a polychromatic image by combining toners of a plurality of colors, and the format and so forth are not particularly limited. 
     The foregoing description of the exemplary embodiments of the present disclosure has been provided for the purposes of illustration and description. It is not intended to be exhaustive or to limit the disclosure to the precise forms disclosed. Obviously, many modifications and variations will be apparent to practitioners skilled in the art. The embodiments were chosen and described in order to best explain the principles of the disclosure and its practical applications, thereby enabling others skilled in the art to understand the disclosure for various embodiments and with the various modifications as are suited to the particular use contemplated. It is intended that the scope of the disclosure be defined by the following claims and their equivalents.