Heating device

Abstract

To provide a heating device and the like capable of suppressing asymmetrical temperature unevenness in the axial end region of a heating roll provided with a resistance heating layer that generates heat by current conduction, as compared with the case where auxiliary heating means is not included that supplementarily heats at least the axial end region of a heat-generating region by the resistance heat generation layer of the heating roll.SOLUTION: The heating device comprises: a heating roll having a resistance heating layer that generates heat by current conduction; a support member for supporting a processing part subjected to heat treatment; a belt which is arranged around at least the heating roll and the support member and moves around; a pressure rotor that rotates pressing a sheet-like object to be heated that is subjected to heat treatment, against the processing part composed of an outer circumferential portion of the belt that is supported by the support member so as to cause the sheet-like object to be heated to pass through the processing part; and auxiliary heating means for supplementarily heating at least an axial end region of a region heated by the resistance heating layer of the heating roll.SELECTED DRAWING: Figure 4

Description

[Technical field]

[0001] This invention relates to a heating device. Place This is related to. [Background technology]

[0002] Patent Document 1 describes a fixing heat roller that includes a roller body formed in a hollow shape and a resistance heating member that generates heat when a predetermined drive signal is applied, and that heats and fixes a recording material attached to a recording medium that is conveyed in contact with the outer circumferential surface of the roller body by conducting heat generated by the resistance heating member to the outer circumferential surface of the roller body, and a fixing device in which the fixing heat roller is pressed into contact with a pressure roller. Patent Document 1 also describes that the fixing heat roller is configured with a heat generating member sheet having a resistance heating member fixed to one side of an insulating film material and a heat conductor that conducts heat generated by the resistance heating member fixed to the other side, and that the heat conductor is in contact with the inner circumferential surface of the roller body and is fixed to the inner circumferential surface of the roller body with the resistance heating member facing the center of the roller body.

[0003] Patent Document 2 describes a fixing device in which a fixing heat roller includes at least a heat generating member for generating heat by applying a voltage and passing a current therethrough, and a cylindrical roller body to which the heat generated from the heat generating member is transferred, and the fixing heat roller is pressed into contact with a pressure roller. Patent Document 2 also describes that the heat generating member is formed by adhering heating elements, which are formed in advance into an arbitrary pattern from a sheet-like resistance heating body, to one side of an insulating film material, and the other side of the insulating film material is fixedly disposed on the inner circumferential surface of the roller body. [Prior art documents] [Patent documents]

[0004] [Patent Document 1] Patent No. 3436437 (Claim 1, Figures 1-6, etc.) [Patent Document 2] JP-A-10-3226 (Claim 1, Figures 1-4, etc.) Summary of the Invention [Problem to be solved by the invention]

[0005] The present invention provides a heating device that can suppress temperature unevenness in an axial end region of a heating roll provided with a resistance heating layer that generates heat when current is applied, compared to a case in which an auxiliary heating means is not provided for auxiliary heating of at least the axial end region of the heat generation region of the resistance heating layer of the heating roll. Place It is what we provide. [Means for solving the problem]

[0006] The present invention (1) provides a heating device comprising: a heating roll having a resistance heating layer that generates heat when electricity is applied; a pressure rotating body that rotates so as to press a sheet-shaped heated object to be heat-treated against the outer circumferential surface of the heating roll and pass the object; and auxiliary heating means that auxiliary heats at least an end region in the axial direction of the heat-generating region of the resistance heating layer of the heating roll. 、 the auxiliary heating means is an auxiliary resistance heating layer that is partially provided on an inner peripheral surface of the heating roll where the resistance heating layer is not provided, The auxiliary resistive heating layer is a layer having a spiral pattern extending in the axial direction, and the width of the portions corresponding to the regions at both ends of the heat generating region is narrower than the width of the portions corresponding to the remaining regions other than the both ends of the heat generating region. It is a heating device.

[0007] This invention (2) is a heating device comprising a heating roll having a resistance heating layer that generates heat when electricity is passed through it, a support member that supports a processing section where heat treatment is performed, a belt that rotates while being at least wrapped around the heating roll and the support member, a pressure rotor that rotates to press a sheet-like heated object to be heat-treated against and pass through the processing section formed by the outer circumferential surface portion of the belt supported by the support member, and an auxiliary heating means that auxiliary heats at least the end region in the axial direction of the heat generation area generated by the resistance heating layer of the heating roll.

[0008] This invention (3) is, The heating device includes a heating roll having a resistance heating layer that generates heat when electricity is applied thereto, a pressure rotating body that rotates so as to press a sheet-shaped heated object to be heat-treated against the outer peripheral surface of the heating roll and pass the object, and an auxiliary heating means that auxiliary heats at least an end region in the axial direction of a heat generating region of the resistance heating layer of the heating roll, the auxiliary heating means is an auxiliary resistance heating layer partially provided on the outer peripheral surface of the heating roll on which the resistance heating layer is provided, The resistive heating layer and the auxiliary resistive heating layer are layers formed of a spiral pattern extending in parallel in the axial direction, and the width of a portion of the auxiliary resistive heating layer corresponding to an end region of the heat generating region is narrower than the width of the resistive heating layer. It is a heating device 。

[0009] This invention ( 4 )teeth, The heating device includes a heating roll having a resistance heating layer that generates heat when electricity is applied thereto, a pressure rotating body that rotates so as to press a sheet-shaped heated object to be heat-treated against the outer peripheral surface of the heating roll and pass the object, and an auxiliary heating means that auxiliary heats at least an end region in the axial direction of a heat generating region of the resistance heating layer of the heating roll, The resistive heating layer has a thickness in an end region of the heat generating region that is greater than a thickness in a remaining region other than the end region of the heat generating region. It is a heating device 。

[0010] The present invention (5) is a heating device according to the above-mentioned invention (2) or (4), wherein the auxiliary heating means is an auxiliary resistance heating layer partially provided on the outer peripheral surface of the heating roll on which the resistance heating layer is provided. Invention (6) is a heating device according to invention (5) above, wherein the resistive heating layer and the auxiliary resistive heating layer are layers consisting of a spiral pattern extending in parallel in the axial direction, and the width of the portion of the auxiliary resistive heating layer corresponding to the end region of the heating region is narrower than the width of the resistive heating layer. The present invention (7) is a heating device according to the above-mentioned invention (6), wherein the width of the auxiliary resistive heating layer corresponding to the remaining area other than the end area of ​​the heat generating area is wider than the width of the corresponding part of the resistive heating layer. This invention (8) is the above invention (2) or (4) In the heating device, the auxiliary heating means is a resistance heating layer of the heating roll. The auxiliary resistance heating layer is provided partially on the inner peripheral surface where no It is a heating device. This invention (9) is the above invention (8) In the heating device, The auxiliary resistive heating layer is a layer having a spiral pattern extending in the axial direction, and the width of the portions corresponding to the regions at both ends of the heat generating region is narrower than the width of the portions corresponding to the remaining regions other than the both ends of the heat generating region. It is a heating device. This invention (10) is the above invention (2) or (4) In the heating device, The auxiliary heating means is an end heating device that heats a portion of the heating roll that corresponds to the end region of the heat generating region. It is a heating device.

[0011] this Invention (11) is In the heating device according to any one of the above inventions (1) to (3), the resistive heating layer has a thickness in the end region of the heat generating region that is thicker than the thickness in the remaining region other than the end region of the heat generating region. It is a device. This invention (12) is the above invention Heating any of (1) to (11) In the apparatus, A heating device is provided which measures the surface temperature of the end regions of the heat generating region of the heating roll and the surface temperature of the remaining region other than the end regions, and the heating state of the auxiliary heating means is adjusted based on the measurement results of the temperature measuring means. It is a device. Effect of the Invention

[0012] The above invention (1 ) As a result, temperature unevenness in the axial end regions of a heating roll having a resistance heating layer that generates heat when electricity is passed through it can be suppressed compared to a case in which an auxiliary heating means is not provided to assist in heating at least the axial end regions of the heat generation region produced by the resistance heating layer of the heating roll. Furthermore, according to the above invention (1), compared to the case where the auxiliary heating means is an auxiliary resistance heating layer that is partially provided on the outer peripheral surface on which the resistance heating layer of the heating roll is provided, it is possible to suppress temperature unevenness in the end region of the heating roll while ensuring smoothness on the outer peripheral surface of the heating roll. Furthermore, according to the above aspect (1), temperature unevenness in the end regions of the heating roll can be easily suppressed, compared to when the auxiliary resistive heating layer is not a layer consisting of a spiral pattern extending parallel to the axial direction.

[0013] The above invention ( 2 ) according to Temperature unevenness in the axial end regions of a heating roll having a resistance heating layer that generates heat when electricity is passed through it can be suppressed compared to a case in which an auxiliary heating means is not provided to assist in heating at least the axial end regions of the heat generation region generated by the resistance heating layer of the heating roll.

[0014] The above invention (3 ) according to Temperature unevenness in the axial end regions of a heating roll having a resistance heating layer that generates heat when electricity is passed through it can be suppressed compared to a case in which an auxiliary heating means is not provided to assist in heating at least the axial end regions of the heat generation region generated by the resistance heating layer of the heating roll. Also, The above invention ( 3 ) according to The manufacturing of the heating roll is easier than when the auxiliary heating means is an auxiliary resistance heating layer partially provided on the inner peripheral surface of the heating roll where no resistance heating layer is provided, The temperature unevenness in the end regions of the heating roll can be easily suppressed. Furthermore, according to the above invention (3), the manufacturing of the heating roll becomes easier than when the resistive heating layer and the auxiliary resistive heating layer are not layers consisting of a spiral pattern extending parallel to the axial direction, and temperature unevenness in the end regions of the heating roll can be easily suppressed.

[0015] The above invention ( 4 ) according to Temperature unevenness in the axial end regions of a heating roll having a resistance heating layer that generates heat when electricity is passed through it can be suppressed compared to a case in which an auxiliary heating means is not provided to assist in heating at least the axial end regions of the heat generation region generated by the resistance heating layer of the heating roll. Also, The above invention ( 4 ) according to The temperature in the end regions in the axial direction of the heat generating region of the resistance heating layer does not become higher than the temperature in the remaining regions other than the end regions, and temperature unevenness in the end regions of the heating roll is easily suppressed. .

[0016] The above invention ( 5 ) according to Compared to a case where the auxiliary heating means is an auxiliary resistance heating layer partially provided on the inner peripheral surface of the heating roll where no resistance heating layer is provided, the manufacturing of the heating roll is made easier, and temperature unevenness in the end regions of the heating roll can be easily suppressed. can. The above invention ( 6 ) according to Compared to a case where the resistive heating layer and the auxiliary resistive heating layer are not layers having a spiral pattern extending parallel to the axial direction, the heating roll is easier to manufacture, and temperature unevenness in the end regions of the heating roll can be easily suppressed. . According to the above invention (7), even if the auxiliary resistive heating layer is a layer having a spiral pattern, it is easier to manufacture the heating roll and temperature unevenness in the end regions of the heating roll can be easily suppressed, compared to a case in which the width of the portion corresponding to the remaining region other than the end region of the heating region of the auxiliary resistive heating layer is not wider than the width of the corresponding portion of the resistive heating layer. According to the above invention (8), compared to the case where the auxiliary heating means is an auxiliary resistance heating layer that is partially provided on the outer peripheral surface on which the resistance heating layer of the heating roll is provided, it is possible to suppress temperature unevenness in the end region of the heating roll while ensuring smoothness on the outer peripheral surface of the heating roll. According to the above aspect (9), the temperature unevenness in the end regions of the heating roll can be easily suppressed, compared to a case in which the auxiliary resistance heating layer is not a layer consisting of a spiral pattern extending parallel to the axial direction. According to the above invention (10), the end regions of the heat generating region can be easily assisted in heating. According to the above invention (11), the temperature in the axial end regions of the heat generating region by the resistance heating layer does not become higher than the temperature in the remaining regions other than the end regions, making it easier to suppress temperature unevenness in the end regions of the heating roll. According to the above aspect (12), the occurrence of temperature unevenness in the end region of the heating roll can be appropriately suppressed, compared to a case in which the heating state of the auxiliary heating means is not adjusted based on the measurement result of the temperature measuring means. [Brief description of the drawings]

[0017] [Figure 1] FIG. 1 is a schematic diagram of an image forming apparatus using a heating device according to a first embodiment. [Diagram 2] 1 is a schematic diagram of a fixing device which is an example of a heating device according to a first embodiment. [Diagram 3] 3 is a schematic diagram of a part of the fixing device in FIG. 2. [Figure 4] FIG. 1A is a schematic cross-sectional view of a heating roll, and FIG. 1B is a schematic cross-sectional view of the heating roll of FIG. [Diagram 5] FIG. 4 is a schematic cross-sectional view of a heating roll used in a modified example of the first embodiment. [Figure 6] FIG. 6 is a schematic diagram of the heating roll of FIG. 5. [Figure 7]13 is a schematic diagram of a fixing device which is another example of a heating device according to the second embodiment. FIG. [Figure 8] 8 is a schematic diagram of a part of the fixing device in FIG. 7. [Figure 9] FIG. 13 is a schematic diagram of a heating and drying device which is another example of a heating device and an apparatus utilizing an object to be heated according to the third embodiment. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0018] Hereinafter, an embodiment of the present invention will be described with reference to the drawings.

[0019] FIG. 1 shows a first embodiment of the present invention. Heating device 5 was used 2 shows an image forming apparatus 1A, and a fixing device 5A which is an example of the heating device 5 according to the first embodiment.

[0020] The apparatus 1 for utilizing an object to be heated is an apparatus that utilizes a sheet-shaped object to be heated 9. The heating device 5 is an apparatus that at least heats the sheet-shaped object to be heated 9. In the following description, the direction indicated by the arrow X in the drawings is the width direction of the device, the direction indicated by the arrow Y is the height direction of the device, and the direction indicated by the arrow Z is the depth direction of the device perpendicular to the width and height directions. The circle at the intersection of the arrows X and Z in the drawings indicates that the arrow Z, which is the depth direction of the device, faces downward perpendicular to the drawing.

[0021] <Heated object utilization device> An image forming apparatus 1A, which is an example of an apparatus 1 utilizing an object to be heated, is an apparatus that forms an image made of a powder developer on a recording medium 9A, which is an example of a sheet-like object to be heated 9, and then heats the recording medium 9A to form an image. 1, this image forming apparatus 1A has a housing 10 having a required external shape, and is configured by arranging an image forming device 2, a medium supplying device 4, a medium conveying device 45, a fixing device 5A, etc. in the internal space of the housing 10. The dashed dotted lines in Fig. 1 indicate the main conveying path when a recording medium 9A is conveyed by the medium conveying device 45 inside the housing 10.

[0022] The image forming device 2 is a device that forms a toner image composed of toner as a developer and transfers it to a recording medium 9A. The image forming device 2 is configured as a device that employs an image forming method such as an electrophotographic method, and is configured by arranging devices such as a charging device 22, an exposure device 23, a developing device 24, a transfer device 25, and a cleaning device 26 around a photosensitive drum 21 that rotates in the direction indicated by arrow A.

[0023] Among these, the photosensitive drum 21 is an example of an image holding means, and is a photosensitive body in the form of a drum having an image forming surface and a photosensitive layer that becomes the image holding surface. The charging device 22 is a device that charges the outer peripheral surface (image forming surface) of the photosensitive drum 21 to a required surface potential. The charging device 22 is configured to include a charging member in the form of, for example, a roll that is brought into contact with the image forming surface of the outer peripheral surface of the photosensitive drum 21 and is supplied with a charging current.

[0024] The exposure device 23 is a device that exposes the charged outer peripheral surface of the photosensitive drum 21 based on image information to form an electrostatic latent image. The exposure device 23 operates by receiving an image signal generated by performing required processing on image information input from the outside by an image processing means (not shown). The image information is information related to the image to be formed, such as characters, figures, photographs, patterns, etc. The development device 24 is a device that develops the electrostatic latent image formed on the outer peripheral surface of the photosensitive drum 21 with a developer (toner) of a corresponding predetermined color (e.g., black) to visualize it as a monochromatic toner image.

[0025] Next, the transfer device 25 is a device that electrostatically transfers the toner image formed on the outer peripheral surface of the photosensitive drum 21 to the recording medium 9A. This transfer device 25 is configured to include a transfer member in the form of a roll or the like that comes into contact with the outer peripheral surface of the photosensitive drum 21 and is supplied with a transfer current. The cleaning device 26 is a device that cleans the outer peripheral surface of the photosensitive drum 21 by removing unnecessary toner, paper powder, and other unnecessary matters that adhere to the outer peripheral surface of the photosensitive drum 21. In the image forming apparatus 2, the portion where the photosensitive drum 21 and the transfer device 25 face each other is the transfer position TP where the toner image is transferred.

[0026] The medium supplying device 4 is a device that stores and sends out the recording medium 9A to be supplied to the transfer position TP in the image forming device 2. This medium supplying device 4 is configured by arranging devices such as one or more storage bodies 41 that store the recording media 9A and one or more delivery devices 43 that send out the recording media 9A one by one. Furthermore, the recording medium 9A is not particularly limited as long as it is a sheet-like recording medium that can be transported by the medium transport device 45 inside the housing 10 and to which a toner image can be transferred and thermally fixed, and there are no particular restrictions on the material, shape, etc. In this image forming apparatus 1A, recording media such as plain paper, coated paper, film, foil, sheet-like cloth, etc. cut to a predetermined size, or a recording medium such as an envelope, etc. are used as the recording medium 9A.

[0027] The medium conveying device 45 is an example of a conveying means for conveying a heated object 9 such as a recording medium 9A, and in this image forming apparatus 1A, it is configured as a device for conveying the recording medium 9A to each required location within the housing 10. The medium conveying device 45 is disposed within the housing 10 so as to form a supply path for conveying the recording medium 9A from the medium supply device 4 to the transfer position TP in the image forming device 2, an intermediate path for conveying the recording medium 9A from the transfer position TP in the image forming device 2 to the fixing device 5A, and a discharge path for conveying the recording medium 9A from the fixing device 5A to a discharge port 12 provided on a side portion or the like of the housing 10. Specifically, the medium conveying device 45 is configured by arranging a pair of conveying rolls 46 (46a to 46d) for sandwiching and conveying the recording medium 9A, guide passage members 47 for forming a conveying space for guiding the recording medium 9A to its destination, and the like, in required positions and in required quantities.

[0028] The fixing device 5A, which is an example of the heating device 5, is a device that applies heat and pressure to fix an unfixed toner image transferred at the transfer position TP of the image forming device 2 onto the recording medium 9A. The fixing device 5A is configured by arranging devices such as a heating rotor 51 and a pressure rotor 61 in the internal space of a housing 50 in which an inlet 50a and an outlet 50b for the recording medium 9A are provided. In addition, in the fixing device 5A, as shown in Figures 1 and 2, the heating rotor 51 and the pressure rotor 61 are arranged to rotate in contact with each other, and are configured as a fixing processing unit FN that heats and pressurizes the recording medium 9A and toner image that pass through the contact area. The fixing device 5A will be described in detail later.

[0029] In the image forming apparatus 1A, an image is formed, for example, in the following manner.

[0030] That is, in the image forming apparatus 1A, when a control means (not shown) receives a command for an operation of forming an image, the image forming device 2 performs a charging operation, an exposing operation, a developing operation and a transferring operation, while the medium supply device 4 performs an operation of feeding out the required recording medium 9A and transporting it to the transfer position TP by the supply path of the medium conveying device 45. As a result, a toner image corresponding to the image information is formed on the photosensitive drum 21, while the toner image is transferred to the recording medium 9A supplied from the medium supply device 4 to the transfer position TP via the medium transport device 45. At this time, the recording medium 9A to which the toner image has been transferred is separated from the photosensitive drum 21 while being sandwiched between the rotating photosensitive drum 21 and the transfer device 25, and then is sent toward the heating device 5 via the relay path of the medium transport device 45.

[0031] 2, in the fixing device 5A of the image forming apparatus 1A, the recording medium 9A onto which the toner image 92 has been transferred is introduced into and passed through the fixing processing section FN at the contact portion between the heating rotator 51 and the pressure rotator 61. As a result, in the fixing device 5A, the unfixed toner image 92 on the recording medium 9A is heated under pressure, melted and fixed to the recording medium 9A. After fixing, the recording medium 9A is ejected from the housing 50 while sandwiched between the heating rotor 51 and the pressure rotor 61 in the fixing device 5A, then transported to the ejection outlet 12 by the ejection path of the media transport device 45, and finally sent by the transport roll 46d to an ejection storage section (not shown) provided in part of the housing 10, where it is stored.

[0032] Through the above series of operations, the basic image forming operation for forming a monochromatic image on one side of one recording medium 9A is completed.

[0033] <Heating device> Next, the fixing device 5A will be described in detail.

[0034] As shown in Figures 2, 3, etc., the fixing device 5A of the first embodiment is configured by using a heating unit 52 in a belt-nip form as the heating rotor 51, while using a pressure roll 62 in a roll form as the pressure rotor 61.

[0035] The heating unit 52 is unitized and mainly includes a heating roll 53A, a supporting member 54, a fixing belt 55, an adjustment supporting roll 56, and the like. As shown in FIG. 4, the heating roll 53A is a laminated roll body in which an electrical insulation layer 532, a first resistance heating layer 533 that generates heat when electricity is passed through it, and an outer surface layer 534 are provided in this order on the outer surface of a cylindrical roll base material 531, while an electrical insulation layer 536, an inner auxiliary resistance heating layer 71 which is an example of auxiliary heating means 7 that assists in heating end regions E1, E2 in the axial direction of the heat generation region produced by the first resistance heating layer 533, and an inner surface layer 538 are provided in this order on the inner surface of the base material 531.

[0036] The roll base material 531 is a cylinder having a thickness of about 0.2 to 1.0 mm and made of a metal material such as aluminum or iron. The electrical insulating layer 532 is an insulating film made of an insulating material such as polyimide or polyether ether ketone (PEEK).

[0037] The first resistive heating layer 533 is a layer that generates heat when electricity is applied, and is provided in a solid manner with a desired thickness on the outer peripheral surface of the heating roll 53 (roll base material 531) in order to heat the entire region of the heating roll 53 to be heated. This first resistive heating layer 533 is a layer or film made of a material such as silver palladium, gold palladium, or a carbon metal filler mixture. This first resistive heating layer 533 is formed by a mold pouring coating method, for example, from the viewpoint of achieving a uniform layer thickness, but may also be formed by a screen printing method or the like. In addition, the first resistive heating layer 533 is adapted to be energized via electrode layers 535 provided at both ends in the axial direction of the roll. The outer surface layer 534 is a layer that has good thermal conductivity and electrical insulation properties, and also has a protective function for protecting the first resistance heating layer 533. This outer surface layer 534 is preferably a layer that has a tackiness for transmitting the rotational force to the fixing belt 55 and wettability with a lubricant, which will be described later, and from this viewpoint is made of a material with low releasability (for example, polyimide, polyether ether ketone (PEEK), etc.).

[0038] The inner auxiliary resistance heating layer 71 is a layer that generates heat when current is passed through it, and is a layer that is partially provided on the inner circumferential surface of the heating roll 53A (the roll base material 531 thereof) in order to supplementarily heat from the inside the left and right end regions E1, E2 in the axial direction of the intended heating area of ​​the heating roll 53A. The inner auxiliary resistance heating layer 71 is a layer or film made of the same material as the first resistance heating layer 533.

[0039] The inner auxiliary resistance heating layer 71 is formed in a spiral pattern extending in the axial direction on the inner circumferential surface of the roll substrate 531. Furthermore, the inner auxiliary resistance heating layer 71 having this spiral pattern is formed such that the spiral pattern widths W1, W2 of the end spiral portions 71A formed in the left and right end regions E1, E2 are narrower than the spiral turn width W3 of the central spiral portion 71B formed in the central region other than the left and right end regions E1, E2. As a result, the inner auxiliary resistance heating layer 71 is configured such that the end spiral portions 71A formed in the left and right end regions E1, E2 have relatively greater resistance and can therefore generate relatively more heat than the central spiral portion 71B formed in the central region.

[0040] The inner auxiliary resistance heating layer 71 is formed by, for example, a mold pouring coating method. The inner auxiliary resistance heating layer 71 is adapted to be energized via electrode layers 539 provided at both ends in the axial direction of the roll. The inner surface layer 538 is a layer having, for example, electrical insulation properties and a protective function for protecting the inner auxiliary resistance heating layer 71 .

[0041] As shown in FIG. 3, the heating roll 53A is rotatably attached at both ends of the roll base 531 to the upper side surface of the housing 50 via bearings 65 such as bearings. The heating roll 53A has a shaft portion at both ends formed of a roll base material 531 protruding outside the bearing 65, and power supply connectors 58A, 58B, 58C, and 58D attached thereto.

[0042] The power supply connectors 58A, 58B, 58C, and 58D have a power supply ring (not shown) disposed inside a cylindrical insulating cover. Of these, the power supply connectors 58A and 58B have a power supply ring electrically connected to an electrode layer 535 for the first resistance heating layer 533 formed on the outer circumferential surface side at both ends of the heating roll 53A. The power supply connectors 58C and 58D have a power supply ring electrically connected to an electrode layer 539 for the inner auxiliary resistance heating layer 71 formed on the inner circumferential surface side at both ends of the heating roll 53A. Furthermore, the power supply connectors 58A, 58B, 58C, and 58D are connected to the power supply device 17, and when heating is required, the power supply device 17 supplies the required current, etc. for the first resistance heating layer 533 to the power supply connectors 58A and 58B, and the power supply device 17 supplies the required current, etc. for the inner auxiliary resistance heating layer 71 to the power supply connectors 58C and 58D.

[0043] The fixing belt 55 is heated by the heating roll 53A and comes into contact with the surface of the recording medium 9A onto which the toner image 92 has been transferred in the fixing processing section FN to perform heating. The fixing belt 55 is an endless heat-conducting belt having flexibility and heat resistance, and is, for example, a belt having a layered structure in which an elastic layer made of an elastic material such as 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 material made of a synthetic resin such as polyimide or polyamide. As shown in FIG. 2, the fixing belt 55 is adapted to rotate in the direction indicated by the arrow C while being wound around a support member 54 and an adjustable support roll 56.

[0044] The support member 54 is a member that is disposed in contact with the inner circumferential surface of the fixing belt 55, and supports and forms the fixing processing section FN where the heat treatment is performed. The fixing processing section FN is a processing section for heat fixing that is formed on the outer circumferential surface portion of the fixing belt 55 that is supported by the support member 54. The support member 54 is configured as a structure in which a hollow plate-shaped support body that is disposed in a state of extending parallel to the axial direction of the heating roll 53, and a pad member is attached to the surface of the support body that comes into contact with the inner circumferential surface of the heating belt 55B. In addition, the support member 54 is disposed by fixing the ends of the support main body, which protrude outward from both ends of the fixing belt 55, to the side surfaces of the housing 50 or the like.

[0045] The adjustment support roll 56 is a roll that maintains the fixing belt 55 in a desired shape while applying a required tension to the wound state of the fixing belt 55, and adjusts the state of the fixing belt 55 so as to stabilize the state of its rotation and running.

[0046] As shown in FIG. 2, the heating unit 52 is also provided with a lubricant application device 57 that applies a lubricant to the inner surface of the fixing belt 55, and a temperature sensor 59 that is an example of a temperature measurement means that measures the surface temperature of the heating roll 53A. 3, the heating unit 52 has a plurality of temperature sensors 59a-59d arranged at predetermined locations in the axial direction of the heating roll 53A (for example, end regions E1, E2 at both ends and a central region other than the end regions) to measure the surface temperatures of the plurality of regions and transmits the measurement results to the control device 15. The control device 15 also controls the operation of the power supply device 17, such as the output, to adjust the heating state.

[0047] On the other hand, the pressure roll 62 is a roll body having a structure in which an elastic release layer 622 is provided on the outer peripheral surface of a columnar or cylindrical roll base material 621 as shown in FIG. As shown in FIG. 2, this pressure roll 62 is rotatably attached to the lower side of the housing 50 at a position facing the support member 54 via bearings 66 attached to shaft portions 623 protruding from both ends of the roll base material 621.

[0048] In addition, this pressure roll 62 is mounted so that the bearing 66 can be displaced in the direction of approaching and moving away from the support member 54, and a predetermined pressure toward the support member 54 is applied to the bearing 66 by a spring or other biasing member not shown, so that the fixing belt 55 is pressed against the support member 54 (its pad member) with a predetermined pressure and passes through it. Furthermore, this pressure roll 62 has a power receiving part 67, such as a gear, attached to one shaft portion thereof for receiving rotational power transmitted when a fixing operation or the like is performed. The power receiving part 67 is configured so that rotational power is transmitted via a final transmission gear 18 from a drive device (not shown) disposed within the housing 10 of the image forming apparatus 1A.

[0049] In the fixing device 5A, when it is time to perform the fixing operation, the first resistance heating layer 533 of the heating roll 53A in the heating unit 52 generates heat by energization and starts to heat the heating roll 53A to keep it at a required temperature. In the fixing device 5A, as illustrated in Fig. 2, the pressure roll 62 is driven to rotate in the direction indicated by the arrow B, and the rotational force of the pressure roll 62 is transmitted to the fixing belt 55 that comes into contact with the pressure roll 62 at the fixing processing part FN, so that the fixing belt 55 starts to rotate in the direction indicated by the arrow C. As a result, the fixing device 5A is ready for a fixing operation by rotating so that the fixing belt 55 passes through the fixing processing section FN while being heated to a required temperature by the heating roll 53A.

[0050] In addition, in this fixing device 5A, when the control device 15 determines based on detection information from the multiple temperature sensors 59a to 59d that the surface temperatures of the left and right end regions E1, E2 in the axial direction of the intended heating area of ​​the heating roll 53A are lower than the surface temperature of the central area other than that, electricity is passed from the power supply device 17 to the inner auxiliary resistance heating layer 71 in the heating roll 53A to generate heat. At this time, the left and right end spiral portions 71A of the inner auxiliary resistance heating layer 71 consisting of a spiral pattern generate more heat than the central spiral portion 71B, and therefore supplementarily heat the left and right end regions E1, E2 of the heating roll 53A. Note that at this time, the central spiral portion 71B of the inner auxiliary resistance heating layer 71 also generates heat to a certain extent, and therefore supplementarily heats the central region of the heating roll 53A.

[0051] Therefore, in this fixing device 5A, even if there are temperature unevenness in the axial end regions E1, E2 of the heating roll 53A provided with the first resistance heating layer 533, auxiliary heating by the inner auxiliary resistance heating layer 71 is obtained, and the temperature unevenness is suppressed compared to a case in which the heating roll 53A does not have an inner auxiliary resistance heating layer 71 that auxiliary heats at least the axial end regions E1, E2 of the heat generation area provided by the first resistance heating layer 533, so that the temperature unevenness is suppressed. Incidentally, the fixing device 5A is also configured so that the inner auxiliary resistance heating layer 71 is energized to generate heat from the very beginning, for example, when the fixing device 5A is started for the first time or when it is restarted after a long period of stoppage.

[0052] <Modification of the first embodiment> In the fixing device 5A, the heating roll 53B having the following configuration example can be used in place of the heating roll 53A. The heating roll 53B shown in Figures 5 and 6 differs from the heating roll 53A in that nothing is provided on the inner surface of the roll substrate 531, and a second resistance heating layer 533B having a spiral pattern and an outer auxiliary resistance heating layer 72 having a spiral pattern are provided on the outer surface thereof. Otherwise, the heating roll 53B has the same configuration as the heating roll 53A.

[0053] The second resistive heating layer 533B is provided as a layer consisting of a spiral pattern extending in the axial direction with the same pattern width W4. The second resistive heating layer 533B is the same as the first resistive heating layer 533 except for the provided pattern. The second resistive heating layer 533B is formed by, for example, a screen printing method.

[0054] The outer auxiliary resistance heating layer 72 is provided as a layer consisting of a spiral pattern extending in parallel to the axial direction in the gaps between the spiral patterns of the second resistance heating layer 533B. As with the inner auxiliary resistance heating layer 71, the outer auxiliary resistance heating layer 72 is formed such that the spiral pattern widths W1, W2 of the end spiral portions 72A formed in the left and right end regions E1, E2 are narrower than the spiral turn width W3 of the central spiral portion 72B formed in the central region other than the left and right end regions E1, E2. As with the second resistance heating layer 533B, the outer auxiliary resistance heating layer 72 is also formed by, for example, a screen printing method.

[0055] The second resistive heating layer 533B and the outer auxiliary resistive heating layer 72 generate heat when electricity is passed through electrodes (not shown) formed on the left and right ends of the intended heating area of ​​the heating roll 53B.

[0056] In the fixing device 5A using this heating roll 53B, when electricity is applied from the power supply device 17, the fixing device 5A is heated by the heat generated by the second resistance heating layer 533B and also by the heat generated by the outer auxiliary resistance heating layer 72. At this time, the left and right end spiral portions 72A of the outer auxiliary resistance heating layer 72 having a spiral pattern generate more heat than the central spiral portion 72B, and therefore strongly heat the left and right end regions E1, E2 of the heating roll 53B as auxiliary heating.

[0057] Therefore, even in this fixing device 5A, even if there are temperature unevenness in the axial end regions E1, E2 of the heating roll 53B provided with the second resistance heating layer 533B, auxiliary heating by the outer auxiliary resistance heating layer 72 is obtained, and the temperature unevenness is suppressed compared to a case in which the heating roll 53B does not have an outer auxiliary resistance heating layer 72 that auxiliary heats at least the axial end regions E1, E2 of the heat generation area provided by the second resistance heating layer 533B.

[0058] Second embodiment. 7 and 8 show a fixing device 5B which is another example of the heating device 5 according to the second embodiment. The fixing device 5B according to the second embodiment is different from the fixing device 5A according to the first embodiment in that the heating rotator 51 is changed to a heating roll 53C in the form of a roll, but otherwise has the same configuration. Therefore, in the following explanation and drawings, the same components as those in the first embodiment are denoted by the same reference numerals, and the explanation thereof will be omitted unless necessary.

[0059] The heating roll 53C in the fixing device 5B can be the heating rolls 53A and 53B exemplified in the first embodiment. In that case, however, it is necessary to appropriately change the conditions such as the thickness of the roll base material 531. In addition, when the heating rolls 53A and 53B are applied, it is not necessary to provide an electrical insulating layer, an inner resistance heating layer, and an inner surface layer on the inner peripheral surface of the roll. Furthermore, when the heating rolls 53A and 53B are applied, the outer surface layer 534 provided on the outer peripheral surface of the roll has good thermal conductivity and electrical insulation properties, and is a layer that has a protective performance for protecting the resistance heating layer 533. Moreover, the outer surface layer 534 is a layer that is required to have good releasability, and is therefore made of a material (such as fluororesin) that has excellent releasability.

[0060] Furthermore, even in a fixing device 5B employing a heating roll 53C having this roll configuration, even if there are temperature unevenness in the axial end regions E1, E2 of the heating roll 53C (53A, 53B) provided with the first resistive heating layer 533 or the second resistive heating layer 533B, the temperature unevenness is suppressed because auxiliary heating is performed by the inner auxiliary resistive heating layer 71 or the outer auxiliary resistive heating layer 72, compared to a case in which the heating roll does not have an inner auxiliary resistive heating layer 71 or an outer auxiliary resistive heating layer 72 that assists in heating at least the axial end regions E1, E2 of the heat generation area provided by the first resistive heating layer 533 or the second resistive heating layer 533B.

[0061] Third embodiment. FIG. 9 shows a heating device 5C which is yet another example of the heating device 5 according to the third embodiment, and a heating and drying device 1B which is another example of the apparatus 1 utilizing an object to be heated that uses the heating device 5C. Heating device 5C according to the third embodiment is different from fixing device 5A according to the first embodiment in that fixing belt 55 is replaced with heating belt 55B, but otherwise has the same configuration. Therefore, in the following description and drawings, the same components as those in the first embodiment are denoted by the same reference numerals, and their description will be omitted unless necessary.

[0062] In this heating device 5C, a belt having good thermal conductivity is applied as the heating belt 55B, and for example, a belt made of a cylindrical belt base material made of a synthetic resin such as polyimide, polyamide, etc. Note that the fixing belt 55 may be used as the heating belt 55B. In the heating device 5C, a portion where the portion of the heating belt 55B supported by the supporting member 54 and the pressure roll 62 are in pressure contact with each other is configured as a drying processing portion DN where the heating and drying processing is performed.

[0063] The heating and drying apparatus 1B using this heating apparatus 5C includes a sheet conveying apparatus 45B that conveys a sheet-like object 9B that needs to be heated and dried as the object 9 to be heated and dried through a drying processing section DN of the heating apparatus 5C. The sheet conveying apparatus 45B is composed of a pair of conveying rolls 48, a guide member 49, etc. Examples of the sheet-like object 9B include the above-mentioned recording medium 9A.

[0064] Even in this heating device 5C, even if there are temperature unevenness in the axial end regions E1, E2 of the heating roll 53A provided with the first resistance heating layer 533, auxiliary heating is obtained by the inner auxiliary resistance heating layer 71, and the temperature unevenness is suppressed compared to a case in which the heating roll 53A does not have an inner auxiliary resistance heating layer 71 that assists in heating at least the axial end regions E1, E2 of the heat generation area provided by the first resistance heating layer 533, so that the temperature unevenness is suppressed. As a result, the heating and drying apparatus 1B can perform good heating and drying on the sheet-like material 9B while suppressing the occurrence of uneven heating and drying caused by the above-mentioned temperature unevenness of the heating roll 53 in the heating apparatus 5C.

[0065] Variations. The present invention is not limited to the configuration examples exemplified in the above-described embodiments, but also includes, for example, the following modified examples.

[0066] In addition to the inner auxiliary resistance heating layer 71 and the outer auxiliary resistance heating layer 72, the auxiliary heating means 7 may be an end heating device such as a halogen lamp for heating the portions corresponding to the end regions E1 and E2 of the heat generating region of the first or second resistance heating layer 533 and 533B of the heating roll 53A (53B). hand Good too.

[0067] Furthermore, for the heating rolls 53A, 53B, and 53C, the film thickness of the end regions E1 and E2 of each heat generating region of the first resistive heating layer 533 and the second resistive heating layer 533B may be set to be thicker than the film thickness of the remaining (central) region other than the end regions E1 and E2. In this case, since the film thickness is thick in the end regions E1 and E2 of the heat generating region of the heating roll 53A, etc., the amount of heat generated is reduced and a drop in temperature occurs, but the drop in temperature and the insufficient heat generation in the end regions E1 and E2 can be compensated for by auxiliary heating using the auxiliary heating means 7.

[0068] In the fixing device 5A, it is possible to omit the adjustment support roll 56 in the heating unit 52. In addition, in the fixing devices 5A and 5B and the heating device 5C, as the pressure rotating body 61 thereof, for example, a pressure rotating body in a belt-nip form may be applied instead of the pressure rolling roll 62 in a roll form.

[0069] In addition, in the first embodiment, etc., a configuration example of image forming apparatus 1A that forms a monochrome image has been shown, but it may also be an apparatus that forms a multi-color image by combining toner of multiple colors, and there are no particular limitations on the type, etc. [Explanation of symbols]

[0070] 1A …Image forming equipment (an example of a device that utilizes a heated object) 1B...Heat drying device (an example of a device that uses heated objects) 5,5C…Heating device 5A, 5B... Fixing device (an example of a heating device) 7...Auxiliary heating means 9 …Sheet-shaped heated object 9A…Recording medium (an example of a sheet-shaped object to be heated) 9B...Sheet-like object (an example of a sheet-like object to be heated) 53A, 53B, 53C...Heating roll 54...Support member 55...Fuser belt (an example of a belt) 55B…Heating belt (an example of a belt) 59...Temperature sensor (an example of a temperature measuring means) 61...Pressurizing rotor 62...Pressure roll (an example of a pressure rotating body) 71...Inner auxiliary resistance heating layer (an example of an auxiliary heating means) 72...Outer auxiliary resistance heating layer (an example of an auxiliary heating means) 533...First resistive heating layer (an example of a resistive heating layer) 533B…Second resistive heating layer (an example of a resistive heating layer) FN: Fixing processing section (an example of a processing section) DN: Drying processing section (an example of a processing section)

Claims

1. A heating roll having a resistance heating layer that generates heat when electricity is applied; A pressurizing rotor that rotates to press a sheet-shaped object to be heated against an outer peripheral surface of the heating roll and pass the sheet-shaped object to be heated; an auxiliary heating means for auxiliary heating at least an end region in an axial direction of a heat generating region of the resistance heating layer of the heating roll; Equipped with the auxiliary heating means is an auxiliary resistance heating layer that is partially provided on an inner peripheral surface of the heating roll where the resistance heating layer is not provided, A heating device in which the auxiliary resistive heating layer is a layer consisting of a spiral pattern extending in the axial direction, and the width of the portions corresponding to the regions at both ends of the heat generating region is narrower than the width of the portions corresponding to the remaining regions other than the ends of the heat generating region.

2. A heating roll having a resistance heating layer that generates heat when electricity is applied; A support member for supporting a processing section where a heat treatment is performed; a belt that is rotated at least around the heating roll and the support member; A pressurizing rotor that rotates to press a sheet-shaped object to be heated to pass through a processing section formed of an outer peripheral surface section of the belt supported by the support member; an auxiliary heating means for auxiliary heating at least an end region in an axial direction of a heat generating region of the resistance heating layer of the heating roll; A heating device comprising:

3. A heating roll having a resistive heating layer that generates heat when electricity is passed through it; A pressurizing rotor that rotates to press a sheet-shaped object to be heated against an outer peripheral surface of the heating roll and pass the sheet-shaped object to be heated; an auxiliary heating means for auxiliary heating at least an end region in an axial direction of a heat generating region of the resistance heating layer of the heating roll; Equipped with the auxiliary heating means is an auxiliary resistance heating layer partially provided on the outer peripheral surface of the heating roll on which the resistance heating layer is provided, A heating device in which the resistive heating layer and the auxiliary resistive heating layer are layers consisting of a spiral pattern extending in parallel in the axial direction, and the width of the portion of the auxiliary resistive heating layer corresponding to the end region of the heat generating region is narrower than the width of the resistive heating layer.

4. A heating roll having a resistive heating layer that generates heat when electricity is passed through it; A pressurizing rotor that rotates to press a sheet-shaped object to be heated against an outer peripheral surface of the heating roll and pass the sheet-shaped object to be heated; an auxiliary heating means for auxiliary heating at least an end region in an axial direction of a heat generating region of the resistance heating layer of the heating roll; Equipped with A heating device, wherein the resistive heating layer has a thickness greater in an end region of the heat generating region than in a remaining region other than the end region of the heat generating region.

5. A heating device as described in claim 2 or 4, wherein the auxiliary heating means is an auxiliary resistive heating layer partially provided on the outer peripheral surface of the heating roll on which the resistive heating layer is provided.

6. A heating device as described in Claim 5, wherein the resistive heating layer and the auxiliary resistive heating layer are layers consisting of a spiral pattern extending parallel to the axial direction, and the width of the portion of the auxiliary resistive heating layer corresponding to the end region of the heating region is narrower than the width of the resistive heating layer.

7. A heating device as described in Claim 6, wherein the width of the auxiliary resistive heating layer corresponding to the remaining area other than the end area of ​​the heating area is wider than the width of the corresponding portion of the resistive heating layer.

8. A heating device as described in claim 2 or 4, wherein the auxiliary heating means is an auxiliary resistive heating layer partially provided on the inner surface of the heating roll where the resistive heating layer is not provided.

9. A heating device as described in Claim 8, wherein the auxiliary resistive heating layer is a layer consisting of a spiral pattern extending in the axial direction, and the width of the portions corresponding to the regions at both ends of the heating region is narrower than the width of the portions corresponding to the remaining regions other than the two ends of the heating region.

10. A heating device as described in claim 2 or 4, wherein the auxiliary heating means is an end heating device that heats a portion corresponding to the end region of the heat generating area of ​​the heating roll.

11. A heating device as described in any one of claims 1 to 3, wherein the resistive heating layer has a thickness in the end regions of the heating region that is thicker than the thickness of the remaining regions other than the end regions of the heating region.

12. A temperature measuring means is provided for measuring the surface temperature of the end region of the heat generating region of the heating roll and the surface temperature of the remaining region other than the end region, The heating device according to claim 1 , wherein the heating state of the auxiliary heating means is adjusted based on the measurement result of the temperature measuring means.

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