Heating device and image forming apparatus

Abstract

To prevent conduction failure caused by damage to a rotating resistance heating element during attachment and detachment of a connector, and prevent conduction failure when the resistance heating element is rotated.SOLUTION: A heating device has: a resistance heating element that rotates and has an electrode part receiving supply of power; a connector that is attached to the resistance heating element, has a contact terminal rotating together with the resistance heating element, and supplies power to the resistance heating element through the contact terminal; and a pressing structure that presses the contact terminal against the electrode part after the resistance heating element is attached to the connector.SELECTED DRAWING: Figure 4

Description

[Technical field]

[0001] The present invention relates to a heating device and an image forming apparatus. [Background technology]

[0002] Patent Document 1 discloses a technology in which, in a heating device, the contact terminal has a contact portion that makes contact with the heater electrode, and a hook-shaped portion provided in an area downstream of the contact portion in the heater entry direction. This prevents the contact portion of the contact terminal protruding into the connector opening from coming into contact with a member inserted into the opening and becoming worn, thereby suppressing poor conductivity. Patent document 2 discloses a technology in which, in an image forming apparatus equipped with a fixing device that uses a rotating heat fixing roller, the heat fixing roller has an electrode member that passes electricity through the resistive heating element, and this electrode member comes into contact with the resistive heating element at three or more points, thereby ensuring stable conductivity between the resistive heating element and the electrode member. [Prior art documents] [Patent documents]

[0003] [Patent Document 1] JP 2013-235223 A [Patent Document 2] JP 2001-22212 A Summary of the Invention [Problem to be solved by the invention]

[0004] For example, a heating device such as a fixing device used in an image forming apparatus may use a resistance heating element for heating. A connector for supplying power is provided in the heating device using this resistance heating element, and the resistance heating element is provided with an electrode portion that is electrically connected to the connector. The connector and the electrode portion of the resistance heating element are electrically connected by contact terminals. Here, when connecting a connector to supply power to the resistance heating element, the contact terminal may damage the resistance heating element, resulting in poor electrical continuity. In order to prevent this poor electrical continuity, the above-mentioned Patent Document 1 proposes a configuration in which, in a non-rotating resistance heating element, when connecting a connector, the contact terminal is pulled away from the resistance heating element, and after connecting the connector, the contact terminal is moved and pressed from the outside. However, in a rotating resistance heating element, when the resistance heating element and the connector shown in Patent Document 1 are rotated together, the conductor connected to the connector becomes entangled, so this configuration cannot be adopted as it is. In addition, when the configuration shown in Patent Document 1 is adopted as it is and the contact terminal is fixed in position and brought into contact with the rotating resistance heating element, the pressure of the contact terminal cannot be kept constant due to micro unevenness occurring on the surface of the resistance heating element, and poor electrical continuity may occur. An object of the present invention is to prevent poor electrical continuity in a rotating resistive heating element due to damage to the resistive heating element when a connector is attached or detached, and to suppress poor electrical continuity when the resistive heating element is rotated. [Means for solving the problem]

[0005] The invention described in claim 1 is a heating device having a rotating resistive heating element having an electrode portion which receives a supply of electric power, a connector which is attached to the resistive heating element and has a contact terminal which rotates together with the resistive heating element and supplies electric power to the resistive heating element via the contact terminal, and a pressing structure which presses the contact terminal against the electrode portion after the connector is attached to the resistive heating element. The invention described in claim 2 is the heating device described in claim 1, characterized in that the pressing structure comes into contact with the contact terminal as the pressing structure moves in one direction, and presses the contact terminal against the electrode portion. The invention described in claim 3 is the heating device described in claim 2, characterized in that a specific point of the contact terminal is provided on the path of movement of the pressing structure in one direction, and the specific point comes into contact with the pressing structure as the pressing structure moves in the one direction, becoming a point of force, and the electrode portion is pressed at the point of action of the contact terminal. The invention recited in claim 4 is the heating device recited in claim 2, characterized in that the contact terminal is not in contact with the electrode portion before coming into contact with the pressing structure. The invention described in claim 5 is the heating device described in claim 1, characterized in that the pressing structure moves the contact terminal in a direction intersecting the one direction by moving the pressing structure in the one direction, and presses the contact terminal against the electrode portion. The invention recited in claim 6 is the heating device recited in claim 5, characterized in that the one direction of the pressing structure is the same as the axial direction of the rotating resistance heating element. The invention described in claim 7 is the heating device described in claim 1, characterized in that the contact terminal is deformed when the pressing structure presses the contact terminal against the electrode portion. The invention described in claim 8 is the heating device described in claim 7, characterized in that the contact terminal deforms by a spring structure, with the upstream side in the one direction in which the pressing structure moves as a fulcrum, a specific point in contact with the pressing structure as a force point, and a point in contact with the electrode portion as a point of action. The invention described in claim 9 is the heating device described in claim 1, characterized in that the connector comprises an outer ring that rotates together with the resistance heating element, an inner ring that does not rotate together with the resistance heating element, and a power supply ring that is provided between the outer ring and the inner ring and transfers power from the inner ring to the outer ring. The invention recited in claim 10 is the heating device recited in claim 9, characterized in that the pressing structure is pressed into contact with the inner ring of the connector. An eleventh aspect of the present invention is the heating device according to the ninth aspect, characterized in that the pressing structure is pressed into contact with the outer ring of the connector and rotates in conjunction with the rotation of the outer ring. The invention described in claim 12 is a heating device described in any one of claims 9 to 11, characterized in that the inner ring has a cavity inside the inner ring for passing a heating lamp that heats the resistance heating element. The invention described in claim 13 is the heating device described in claim 1, characterized in that the pressing structure releases the pressing of the contact terminal against the electrode portion as the contact terminal moves in a direction opposite to the one direction. The invention described in claim 14 is a heating device described in claim 13, characterized in that the pressing structure releases contact with the contact terminal as the pressing structure moves in the reverse direction, and the release of contact releases the contact terminal from the electrode portion. The invention described in claim 15 is an image forming apparatus comprising: a developing unit that develops an electrostatic latent image on a photosensitive member; a transfer unit that transfers the developed image to paper; a resistive heating element that has an electrode portion that receives power and rotates; a connector that is attached to the resistive heating element and has a contact terminal that rotates together with the resistive heating element and supplies power to the resistive heating element via the contact terminal; and a pressing structure that presses the contact terminal against the electrode portion after the connector is attached to the resistive heating element, and a fixing device that fixes the paper to which the image has been transferred. Effect of the Invention

[0006] According to the invention recited in claim 1, in a rotating resistive heating element, poor conductivity caused by damage to the resistive heating element when a connector is attached or detached can be prevented, and poor conductivity when the resistive heating element is rotated can be suppressed. According to the invention as recited in claim 2, the contact terminal can be pressed against the electrode portion by a simple action. According to the invention as recited in claim 3, even when the contact terminal is pressed against the electrode portion by a simple action, a pressing force can be obtained. According to the invention recited in claim 4, damage to the resistance heating element when the connector is attached or detached can be prevented, compared to a case in which the contact terminal is in contact with the electrode portion before coming into contact with the pressing structure. According to the invention as recited in claim 5, the degree of freedom in designing the pressing structure is improved compared to a case in which the moving direction of the contact terminal coincides with one direction of the pressing structure. According to the invention described in claim 6, workability in installing the pressing structure on the resistance heating body is improved compared to a case in which one direction of the pressing structure is not the same as the axial direction of the rotating resistance heating body. According to the seventh aspect of the present invention, the contactability can be improved by utilizing the deformation force generated when the contact terminal is deformed. According to the eighth aspect of the invention, contactability can be improved compared to a case in which a spring structure is not utilized for deformation of the contact terminal. According to the ninth aspect of the present invention, a stable supply of power to the rotating resistance heating element can be ensured. According to the invention as set forth in claim 10, the pressing structure can be simplified. According to the invention recited in claim 11, friction between the contact terminal and the pressing structure is suppressed compared to a case in which the pressing structure does not contact the outer ring of the connector. According to the invention as recited in claim 12, the heating lamp is provided in the cavity, so that the resistance heating element can be efficiently heated. According to the invention as set forth in claim 13, the pressing force can be released when the connector is removed. According to the invention as set forth in claim 14, damage to the resistance heating element when the connector is removed can be prevented. According to the invention described in claim 15, an image forming device can be provided that prevents poor conductivity in a rotating resistive heating element due to damage to the resistive heating element when a connector is attached or detached, and suppresses poor conductivity when the resistive heating element is rotated. [Brief description of the drawings]

[0007] [Figure 1] FIG. 1 is a diagram illustrating an image forming apparatus according to an embodiment of the present invention. [Diagram 2] FIG. 2 is an enlarged view of the fixing device shown in FIG. 1, illustrating the fixing device according to the present embodiment. [Diagram 3] FIG. 2 is a perspective view illustrating a resistance heating element according to the present embodiment. [Figure 4]4 is a diagram illustrating an electrode portion of a resistive heating element and a connector in the present embodiment, and is a cross-sectional view taken along line IV-IV in FIG. [Diagram 5] 5(a) to 5(c) are diagrams for explaining contact with the contact terminals by the outer cover in this embodiment, and are diagrams showing the upper part of the resistance heating element in FIG. [Figure 6] 13(a) to 13(c) are diagrams illustrating modified examples of the connector. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0008] Hereinafter, the present embodiment will be described in detail with reference to the accompanying drawings. [Description of Image Forming Apparatus] FIG. 1 is a diagram illustrating an image forming apparatus 1 according to the present embodiment. The image forming apparatus 1 according to the present embodiment includes a paper feed unit 1A, a printing unit 1B, and a paper discharge unit 1C. The paper feed unit 1A includes a first paper storage section 11 to a fourth paper storage section 14 for storing paper P as an example of a recording medium. The paper feed unit 1A also has feed rolls 15-18 that correspond to the first paper storage section 11 to the fourth paper storage section 14, respectively, and feed the paper P stored in each paper storage section to a transport path connected to the printing unit 1B.

[0009] The printing unit 1B includes an image forming section 20 that forms an image on a sheet P. The printing unit 1B also includes a control section 21 that controls each section of the image forming apparatus 1. The printing unit 1B also includes an image processing section 22. The image processing section 22 performs image processing on image data transmitted from the image reading device 4 and the personal computer (PC) 5. The printing unit 1B is also provided with a UI (User Interface) 23, which is configured with a touch panel or the like and notifies the user of information and receives information input from the user.

[0010] The image forming section 20 is provided with six image forming units 30T, 30P, 30Y, 30M, 30C, and 30K (hereinafter, sometimes simply referred to as "image forming units 30") that are arranged in parallel at regular intervals. Each image forming unit 30 includes a photosensitive drum 31 on which an electrostatic latent image is formed while rotating in the direction of arrow A, a charging roll 32 which charges the surface of the photosensitive drum 31, a developing device 33 which develops the electrostatic latent image formed on the photosensitive drum 31, and a drum cleaner 34 which removes toner and the like from the surface of the photosensitive drum 31.

[0011] The image forming section 20 is also provided with an exposure device 26 that exposes the photoconductor drum 31 of each image forming unit 30 to laser light. The exposure of the photoconductor drum 31 by the exposure device 26 is not limited to using laser light. For example, a light source such as an LED (Light Emitting Diode) may be provided for each image forming unit 30, and the photoconductor drum 31 may be exposed to light emitted from the light source.

[0012] Each image forming unit 30 is configured similarly, except for the toner contained in the developer 33. The image forming units 30Y, 30M, 30C, and 30K form toner images of yellow (Y), magenta (M), cyan (C), and black (K), respectively. Further, the image forming units 30T and 30P form toner images using toner corresponding to a corporate color, foaming toner for Braille, fluorescent color toner, toner for improving gloss, etc. In other words, the image forming units 30T and 30P form toner images using toner of a special color.

[0013] The image forming section 20 is also provided with an intermediate transfer belt 41 onto which the toner images of each color formed on the photosensitive drums 31 of the image forming units 30 are transferred. The image forming section 20 is also provided with a primary transfer roll 42 that transfers the respective color toner images of the respective image forming units 30 onto the intermediate transfer belt 41 at a primary transfer portion T1. The image forming unit 20 is also provided with a secondary transfer roll 40 that transfers the toner image transferred onto the intermediate transfer belt 41 onto the paper P at a secondary transfer portion T2. Furthermore, the image forming section 20 is provided with a belt cleaner 45 that removes toner and the like from the surface of the intermediate transfer belt 41, and a fixing device 80 that fixes the secondarily transferred image onto the paper P.

[0014] The image forming unit 20 performs an image forming operation based on a control signal from the control unit 21 . Specifically, in the image forming unit 20, first, image processing is performed on the image data input from the image reading device 4 or the PC 5 by the image processing unit 22, and the image data after image processing is supplied to the laser exposure device 26. Then, for example, in a magenta (M) image forming unit 30M, the surface of the photosensitive drum 31 is charged by the charging roll 32, and then the laser exposure device 26 irradiates the photosensitive drum 31 with laser light modulated by image data obtained from the image processing unit 22.

[0015] As a result, an electrostatic latent image is formed on the photoconductor drum 31 . The formed electrostatic latent image is developed by the developing unit 33, and a magenta toner image is formed on the photosensitive drum 31. Similarly, yellow, cyan and black toner images are formed in the image forming units 30Y, 30C and 30K, and special color toner images are formed in the image forming units 30T and 30P.

[0016] The respective color toner images formed in each image forming unit 30 are electrostatically transferred sequentially by a primary transfer roll 42 onto an intermediate transfer belt 41 rotating in the direction of arrow C in Figure 1, and superimposed toner images are formed on the intermediate transfer belt 41. The superimposed toner image formed on the intermediate transfer belt 41 is transported to a secondary transfer portion T2 constituted by a secondary transfer roll 40 and a backup roll 49 as the intermediate transfer belt 41 moves.

[0017] On the other hand, the paper P is taken out from the first paper storage unit 11 by, for example, the delivery roll 15, and then transported to the position of the registration roll 74 via the transport path. When the superimposed toner image is transported to the secondary transfer portion T2, a sheet of paper P is supplied from the registration roll 74 to the secondary transfer portion T2 in accordance with the transport timing. Then, in the secondary transfer portion T2, the superimposed toner images are electrostatically transferred onto the paper P all at once by the action of a transfer electric field formed between the secondary transfer roll 40 and the backup roll 49.

[0018] Thereafter, the paper P onto which the superimposed toner images have been electrostatically transferred is transported to a fixing device 80. In the fixing device 80, pressure and heat are applied to the sheet P on which the unfixed toner image has been formed, and a process of fixing the toner image to the sheet P is carried out. The fixing device 80 is an example of a heating device. Then, the sheet P on which the fixing process has been performed passes through a curl correction section 79 provided in the sheet discharge unit 1C, and is then conveyed to a sheet stacking section (not shown).

[0019] [Description of Fixing Device 80] FIG. 2 is a diagram for explaining the fixing device 80 in the present embodiment, and is an enlarged view of the fixing device 80 shown in FIG. 1. As shown in FIG. 2, the fixing device 80, which is one of the heating devices, includes a cylindrical pressure roll 81 that presses the paper P, a fixing belt 82 that heats the paper P together with the pressure roll 81, a cylindrical resistance heating element 100 that heats the fixing belt 82, a fixed pad 83 that is disposed in a position facing the pressure roll 81 and presses the paper P together with the pressure roll 81, and a cylindrical steering roll 84 that is disposed between the resistance heating element 100 and the fixed pad 83 and applies tension to the fixing belt 82. The pressure roll 81 is configured to be rotated by a motor (not shown), and the fixing belt 82 rotates together with the rotation of the pressure roll 81. The fixing belt 82 is stretched around the fixed pad 83, the steering roll 84, and the resistance heating element 100 in a state of tension. Therefore, when the fixing belt 82 rotates due to the rotation of the pressure roll 81, the steering roll 84 and the resistance heating element 100 rotate around their respective rotation axes.

[0020] In this embodiment, the fixing device 80 is configured to transport the paper P in the paper transport direction by rotating both the pressure roll 81 and the fixing belt 82. While transporting the paper P, the fixing device 80 heats the paper P with the fixing belt 82 heated by the resistance heating element 100, and applies pressure to the paper P with the fixed pad 83 and the pressure roll 81, thereby performing a fixing process.

[0021] Fig. 3 is a diagram for explaining the resistance heating element 100 in this embodiment, showing a perspective view of the resistance heating element 100 shown in Fig. 2 as seen from direction III. Shown here is a connector 200 that is attached to the resistance heating element 100 and supplies power to the resistance heating element 100 via contact terminals (described later). This connector 200 is configured to heat a heat generating layer (described later) of the resistance heating element 100 by supplying power to electrode portions (described later) of the resistance heating element 100.

[0022] The resistance heating element 100 has a heating lamp 101 disposed therein for heating the resistance heating element 100, and a harness 102 for transferring power to an inner ring (described later) of a connector 200. The heating lamp 101 includes a center heating lamp (not shown) and an end heating lamp (not shown). Heating of the heat generating layer (described later) of the resistance heating element 100 and heating of the heating lamp 101 are used separately to perform a heating process according to the paper size. For example, when a small-sized paper P is heated, the heating process is performed by the center heating lamp of the heating lamp 101. Also, when a large-sized paper P is heated, the heating process is performed by heating the heat generating layer (described later) by the connector 200 and by the end heating lamp of the heating lamp 101 for heating the outside of the heat generating layer (described later).

[0023] FIG. 4 is a diagram for explaining the electrode portion 110 of the resistance heating element 100 and the connector 200 in this embodiment, and is a cross section taken along the line IV-IV in FIG. 3. FIG. 4 shows a state in which the connector 200 is installed on the resistance heating element 100. As shown in FIG. 4, the resistance heating element 100 has an electrode portion 110 that receives power from the connector 200. The electrode portion 110 is provided along the inner circumferential surface of the resistance heating element 100. When the resistance heating element 100 is made of a conductive material, such as iron or aluminum, the entire inner circumferential surface is covered with an insulator, such as polyimide, and the electrode portion 110 is provided on the inner circumferential surface of the insulator. The electrode portion 110 includes a heat generating layer 111 that generates heat by electrical resistance, and a current carrying layer 112 that is arranged on an extension of the heat generating layer 111 and transfers power from the connector 200 to the heat generating layer 111. The current-carrying layer 112 is made of a material that has low electrical resistance and easily conducts electricity, such as gold or silver, and prevents heat from being generated anywhere other than the heat-generating layer 111 .

[0024] 4, the connector 200 has a contact terminal 210 that supplies power by contacting the current-carrying layer 112 of the electrode portion 110. The contact terminal 210 is made of a plate-like member and has multiple bent portions. The connector 200 also has an outer cover 220 that presses the contact terminal 210 against the current-carrying layer 112 of the electrode portion 110 of the resistance heating element 100 after the connector 200 is attached to the resistance heating element 100. Furthermore, the connector 200 has an outer ring 230, an inner ring 240, a power supply ring 250, a ball bearing 260, and a resin member 270. The cylindrical outer ring 230 is provided inside the resistance heating element 100 and rotates together with the resistance heating element 100. The cylindrical inner ring 240 is provided inside the outer ring 230 and does not rotate together with the resistance heating element 100. The power supply ring 250 is provided between the outer ring 230 and the inner ring 240, and transfers power from the inner ring 240 to the outer ring 230. The ball bearing 260 is provided between the outer ring 230 and the inner ring 240. The resin member 270 is located on the upper part of the outer ring 230 and physically connects the connector 200 and the resistance heating element 100. In this embodiment, power is transferred in the order of harness 102, inner ring 240, power supply ring 250, outer ring 230, contact terminal 210, conductive layer 112, and heating layer 111. Note that outer cover 220 is an example of a pressing structure, in which outer cover 220 presses contact terminal 210, and contact terminal 210 contacts conductive layer 112 of electrode portion 110.

[0025] The contact terminal 210 has a spring structure, and the upstream side in one direction in which the external cover 220 moves is a fulcrum 211, a specific point in contact with the external cover 220 is a force point 212, and a point in contact with the current-carrying layer 112 of the electrode unit 110 is a point of application 213. Here, the one direction in which the external cover 220, which is a pressing structure, moves is a direction from the end of the resistance heating element 100 toward the center in the axial direction of the rotating resistance heating element 100. The contact terminal 210, which has a spring structure, is pressed against the external cover 220 and deformed by the movement of the external cover 220 in one direction. The contact terminal 210 is electrically connected to the connector 200 and the resistance heating element 100 by the movement of the external cover 220 in one direction bringing the point of application 213 into contact with the current-carrying layer 112 of the electrode unit 110. In the example shown in FIG. 4, the force point 212 is shown to be the apex of the bent portion of the contact terminal 210, but the force point 212 can also be any point on the slope formed from the fulcrum 211 to the apex of the bent portion.

[0026] A plurality of contact terminals 210 are provided at predetermined intervals on the outer peripheral surface of outer ring 230. Since outer ring 230 rotates together with resistance heating element 100, these plurality of contact terminals 210 also rotate together with resistance heating element 100. Note that plate-shaped contact terminal 210 may be configured to be rounded to match the diameter of outer ring 230 to increase the contact area.

[0027] The outer cover 220 has an insertion part 221 inserted between the outer ring 230 and the inner ring 240, and a pressing part 222 that contacts the force point 212 of the contact terminal 210 and presses the contact terminal 210 against the current-carrying layer 112 of the electrode part 110. A hole 223 for passing the harness 102 is bored in the portion of the outer cover 220 where the harness 102 is arranged. The insertion part 221 is configured in a circumferential shape so as to follow the outer peripheral surface of the inner ring 240, and is configured so as to leave a gap so as not to contact the outer ring 230 during insertion. The insertion part 221 is configured so that the outer cover 220 contacts the inner ring 240 when the insertion part 221 is inserted to a predetermined position. The pressing part 222 is configured to press the contact terminal 210 against the electrode part 110 of the resistance heating element 100 as the insertion part 221 is inserted into the resistance heating element 100. The pressing portion 222 is made of a material with low frictional resistance, and continues to smoothly contact with the contact terminal 210 when the contact terminal 210 rotates in conjunction with the rotation of the resistance heating element 100 .

[0028] The inner ring 240 has a cavity 241 for passing the heating lamp 101 inside the inner ring 240. This allows the resistance heating element 100 to use both the heat generated by the heating layer 111 and the heat generated by the heating lamp 101, improving the efficiency of heating the resistance heating element 100. For example, using only the heat generated by the heating layer 111 at first leads to a reduction in start-up time. The heating lamp 101 is located inside the inner ring 240 and is fixed regardless of the rotation of the resistance heating element 100.

[0029] The power supply ring 250 is a conductor and has a bearing structure. The outer ring 230 is configured to rotate with the rotation of the resistance heating element 100 due to this bearing structure and ball bearing 260. The inner ring 240 is configured not to rotate together with the resistance heating element 100 due to this bearing structure and ball bearing 260. In this way, the position of the inner ring 240 is fixed regardless of the rotation of the resistance heating element 100.

[0030] The resin member 270 has a hole 271 that is hollowed out to follow the peripheral surface of the resistance heating element 100. The connector 200 is attached to the resistance heating element 100 by moving the connector 200 in one direction and passing the surface of the resistance heating element 100 through the hole 271. On the other hand, when removing the connector 200 from the resistance heating element 100, it is sufficient to move the connector 200 in the opposite direction to the one direction.

[0031] [Pressing action due to movement of the outer cover 220 in one direction] Next, the pressing action of the contact terminals 210 caused by moving the outer cover 220 in one direction will be described with reference to FIGS. 5(a) to 5(c). 5(a) to 5(c) are diagrams for explaining contact between the contact terminals 210 and the outer cover 220 in this embodiment, and are diagrams for explaining a cut-out portion of the upper part of the resistance heating element 100 in FIG.

[0032] 5(a) shows a state before the outer cover 220 comes into contact with the contact terminal 210. In FIG. 5(a), the contact terminal 210 is not subjected to any force and is not deformed. The contact terminal 210 is not in contact with the conductive layer 112 of the electrode portion 110.

[0033] FIG. 5(b) shows a state when the pressing portion 222 of the external cover 220 contacts the contact terminal 210. In this state, the action point 213 of the contact terminal 210 is not yet in contact with the conductive layer 112 of the electrode portion 110. By inserting the insertion portion 221 of the external cover 220 between the outer ring 230 and the inner ring 240, the external cover 220 moves in one direction in FIG. 5(b) more than in FIG. 5(a). In this embodiment, the one direction in which the external cover 220 moves is a direction from the end portion of the rotating resistance heating element 100 in the axial direction toward the center. However, the one direction may be an oblique direction angled to the axial direction.

[0034] 5(b), the external cover 220 is further moved in one direction, whereby the pressing portion 222 of the external cover 220 further presses and deforms the contact terminal 210. This gradually brings the point of action 213 of the contact terminal 210 closer to the conductive layer 112 of the electrode section 110. This series of movements moves the external cover 220, which has a pressing structure, in one direction, thereby moving the point of action 213 of the contact terminal 210 in a direction intersecting this one direction, and then the contact terminal 210 is pressed against the electrode section 110.

[0035] FIG. 5(c) shows a state in which the external cover 220 is further moved in one direction from the state of FIG. 5(b), thereby further moving the action point 213 of the contact terminal 210 in the intersecting direction, and as a result, the action point 213 of the contact terminal 210 comes into contact with the conductive layer 112 of the electrode section 110. In FIG. 5(c), the external cover 220 moves further in one direction than in FIG. 5(b), and the external cover 220 comes into contact with the inner ring 240. When the external cover 220 comes into contact with the inner ring 240, the movement of the external cover 220 in one direction is restricted, and the position of the external cover 220 is fixed. In this state, the pressing portion 222 of the external cover 220 comes into contact with the force point 212 of the contact terminal 210, and the contact terminal 210 is given a force in the intersecting direction by the force point 212. The point of application 213 of the contact terminal 210 is in contact with the conductive layer 112 of the electrode portion 110 while being pressed against the conductive layer 112, thereby ensuring stable electrical continuity.

[0036] 5(c), when the resistance heating element 100 rotates, the contact terminal 210 also rotates. Even when the contact terminal 210 rotates, the pressing portion 222, which is a circumferential member and has low frictional resistance, continues to smoothly contact the contact terminal 210. This ensures a stable supply of power to the rotating resistance heating element 100.

[0037] [Release of pressure by moving the outer cover 220 in the opposite direction] The above describes the pressing action caused by moving the external cover 220 in one direction. Next, the pressing release action caused by moving the external cover 220 in the opposite direction will be described with reference to Figures 5(a) to 5(c). The pressing release action will be described in the order of Figures 5(c), 5(b), and 5(a).

[0038] 5(c) shows the state before the external cover 220 is moved to release the pressure. At this time, the pressure portion 222 of the external cover 220 is in contact with the force point 212 of the contact terminal 210, and the action point 213 of the contact terminal 210 is in contact with the current-carrying layer 112 of the electrode portion 110.

[0039] 5(b), when the outer cover 220 is moved in the opposite direction, the contact between the outer cover 220 and the inner ring 240 is released, and the contact between the pressing portion 222 of the outer cover 220 and the force point 212 of the contact terminal 210 is released. Then, the contact between the action point 213 of the contact terminal 210 and the current-carrying layer 112 of the electrode portion 110 is released.

[0040] When the outer cover 220 is further moved in the opposite direction, the contact between the contact terminals 210 and the outer cover 220 is released, and the contact terminals 210 are not subjected to any force from outside and are not deformed, as shown in Fig. 5(a). From the state shown in Fig. 5(a), the connector 200 is further moved in the opposite direction to remove the connector 200 from the resistance heating element 100. This series of removal procedures prevents the contact terminals 210 from damaging the electrode parts 110.

[0041] [Modifications] 6(a) to (c) are diagrams illustrating modified examples of the connector 200. In Fig. 5(a) to (c), a case has been described in which the contact terminals 210 are pressed against the conductive layer 112 of the electrode section 110 on the inner circumferential surface of the resistance heating element 100 by moving the external cover 220 in one direction. On the other hand, in the modified example in Fig. 6(a) to (c), a case has been described in which the contact terminals 210 are pressed against the conductive layer 112 of the electrode section 110 on the outer circumferential surface of the resistance heating element 100 by moving the external cover 220 in one direction. Note that the pressing release action by moving the external cover 220 in the opposite direction is also applied to this modified example.

[0042] 6(a) to 6(c), the electrode portion 110 of the resistance heating element 100 is disposed on the outer peripheral surface of the resistance heating element 100. Also, the outer cover 220 of the connector 200 is configured to come into contact with the outer ring 230. The insertion portion 221 of the outer cover 220 is configured to fit along the inner peripheral surface of the outer ring 230, and a gap is provided so that the insertion portion 221 and the inner ring 240 do not come into contact with each other during insertion.

[0043] Next, the pressing action of the contact terminals 210 caused by moving the outer cover 220 in one direction will be described with reference to FIGS. 6(a) to 6(c).

[0044] 6(a) shows a state before the outer cover 220 comes into contact with the contact terminal 210. In FIG. 6(a), the contact terminal 210 is not subjected to any force and is not deformed. The contact terminal 210 is not in contact with the conductive layer 112 of the electrode portion 110.

[0045] FIG. 6(b) shows a state when the pressing portion 222 of the external cover 220 contacts the contact terminal 210. In this state, the action point 213 of the contact terminal 210 is not yet in contact with the conductive layer 112 of the electrode portion 110. By inserting the insertion portion 221 of the external cover 220 between the outer ring 230 and the inner ring 240, the external cover 220 moves in one direction in FIG. 6(b) more than in FIG. 6(a). In this embodiment, the one direction in which the external cover 220 moves is a direction from the end portion of the rotating resistance heating element 100 in the axial direction toward the center. However, the one direction may be an oblique direction angled to the axial direction.

[0046] 6(b), the external cover 220 is further moved in one direction, whereby the pressing portion 222 of the external cover 220 further presses and deforms the contact terminal 210. This gradually brings the point of action 213 of the contact terminal 210 closer to the conductive layer 112 of the electrode section 110. This series of movements moves the external cover 220, which has a pressing structure, in one direction, thereby moving the point of action 213 of the contact terminal 210 in a direction intersecting this one direction, and then the contact terminal 210 is pressed against the electrode section 110.

[0047] FIG. 6(c) shows a state in which the external cover 220 is further moved in one direction from the state of FIG. 6(b) to further move the action point 213 of the contact terminal 210 in the intersecting direction, resulting in the action point 213 of the contact terminal 210 coming into contact with the conductive layer 112 of the electrode section 110. In FIG. 6(c), the external cover 220 moves further in one direction than in FIG. 6(b), and the external cover 220 comes into contact with the outer ring 230. When the external cover 220 comes into contact with the outer ring 230, the movement of the external cover 220 in one direction is restricted, and the position of the external cover 220 is fixed. In this state, the pressing portion 222 of the external cover 220 comes into contact with the force point 212 of the contact terminal 210, and the contact terminal 210 is given a force in the intersecting direction by the force point 212. The point of application 213 of the contact terminal 210 is in contact with the conductive layer 112 of the electrode portion 110 while being pressed against the conductive layer 112, thereby ensuring stable electrical continuity.

[0048] 6(c), when the resistance heating element 100 rotates, the contact terminals 210 and the outer cover 220 also rotate together. This ensures a stable supply of power to the rotating resistance heating element 100.

[0049] Although the present embodiment has been described above, the present invention is not limited to these embodiments. For example, the external cover 220 may be moved in the vertical direction to come into contact with the contact terminal 210. Also, the external cover 220 may press the contact terminal 210 from a state in which the contact terminal 210 and the electrode unit 110 are in contact. Furthermore, the contact terminal 210 may be in contact with the electrode unit 110 even after the contact between the external cover 220 and the contact terminal 210 is released.

[0050] <Additional Notes> (((1))) a rotating resistance heating element having an electrode portion that receives power; a connector that is attached to the resistance heating element, has a contact terminal that rotates together with the resistance heating element, and supplies power to the resistance heating element via the contact terminal; and a pressing structure for pressing the contact terminal against the electrode portion after the connector is attached to the resistance heating element. (((2))) The heating device according to ((1))), wherein the pressing structure comes into contact with the contact terminal as the pressing structure moves in one direction, and presses the contact terminal against the electrode portion. (((3))) The heating device described in ((1))) or (((2))) is characterized in that a specific point of the contact terminal is provided on a path of movement of the pressing structure in one direction, and the specific point comes into contact with the pressing structure as the pressing structure moves in the one direction, becoming a point of force, and pressing the electrode portion at the point of action of the contact terminal. (((4))) The heating device according to any one of claims ((1)) to ((3)), wherein the contact terminal is not in contact with the electrode portion before coming into contact with the pressing structure. (((5))) The heating device according to any one of claims ((1)) to ((4)) above, wherein the pressing structure moves the contact terminal in a direction intersecting the one direction by moving the pressing structure in the one direction, thereby pressing the contact terminal against the electrode portion. (((6))) The heating device according to any one of ((1)) to (((5))), wherein the one direction of the pressing structure is the same as the axial direction of the rotating resistive heating element. (((7))) The heating device according to ((1))), wherein the contact terminal is deformed when the pressing structure presses the contact terminal against the electrode portion. (((8))) The heating device described in (((7))) is characterized in that the contact terminal is deformed by a spring structure, with the upstream side of the one direction in which the pressing structure moves as a fulcrum, a specific point in contact with the pressing structure as a force point, and a point in contact with the electrode portion as a point of action. (((9))) The connector includes an outer ring that rotates with the resistance heating element; an inner ring that does not rotate together with the resistance heating element; a power supply ring provided between the outer ring and the inner ring for transferring power from the inner ring to the outer ring; The heating device according to (((1))) is characterized by comprising: (((10))) The heating device according to ((9))), wherein the pressing structure is pressed into contact with the inner ring of the connector. (((11))) The heating device according to ((9))) or ((10))), wherein the pressing structure is pressed into contact with the outer ring of the connector and rotates in conjunction with the rotation of the outer ring. (((12))) The heating device according to any one of items ((1))) through (((9))), (((11)) and (((1))), is characterized in that the inner ring has a cavity therein for passing a heating lamp that heats the resistance heating element. (((13))) The heating device according to ((1))), wherein the pressing structure releases the pressing of the contact terminal against the electrode portion as the contact terminal moves in a direction opposite to the one direction. (((14))) The heating device described in (((13))) is characterized in that the pressing structure releases contact with the contact terminal as the pressing structure moves in the reverse direction, and the release of contact releases the contact terminal from the electrode portion. (((15))) a developer for developing the electrostatic latent image on the photoconductor; a transfer section for transferring the developed image onto a sheet of paper; a rotating resistance heating element having an electrode portion that receives power; a connector that is attached to the resistance heating element, has a contact terminal that rotates together with the resistance heating element, and supplies power to the resistance heating element via the contact terminal; a fixing device having a pressing structure for pressing the contact terminals against the electrode portions after the connector is attached to the resistance heating element, and fixing the paper on which the developed image has been transferred; An image forming apparatus comprising:

[0051] According to the heating device of (((1))), in a rotating resistive heating element, poor conductivity caused by damage to the resistive heating element when a connector is attached or detached can be prevented, and poor conductivity when the resistive heating element is rotated can be suppressed. According to the heating device of (((2))), the contact terminal can be pressed against the electrode portion by a simple action. According to the heating device of (((3))), even when the contact terminal is pressed against the electrode portion by a simple action, a pressing force can be obtained. According to the heating device of (((4))), damage to the resistance heating element when attaching or detaching the connector can be prevented compared to a case in which the contact terminal is in contact with the electrode portion before coming into contact with the pressing structure. According to the heating device of (((5))), the degree of freedom in designing the pressing structure is improved compared to a case in which the moving direction of the contact terminal coincides with one direction of the pressing structure. According to the heating device of (((6))), the workability in installing the pressing structure on the resistance heating body is improved compared to a case where one direction of the pressing structure is not the same as the axial direction of the rotating resistance heating body. According to the heating device of (((7))), the contact property can be improved by utilizing the deformation force generated when the contact terminal is deformed. According to the heating device of (((8))), contactability can be improved compared to a case in which a spring structure is not used for deforming the contact terminal. According to the heating device of (((9))), a stable supply of power to the rotating resistive heating element can be ensured. According to the heating device of (((10))), the pressing structure can be simplified. According to the heating device of (((11))), friction between the contact terminal and the pressing structure is suppressed compared to a case in which the pressing structure does not contact the outer ring of the connector. According to the heating device of (((12))), the resistance heating element can be efficiently heated by providing the heating lamp in the cavity. According to the heating device of (((13))), the pressure can be released when the connector is removed. The heating device according to (((14))) can prevent damage to the resistance heating element when the connector is removed. According to the image forming apparatus of (((15))), it is possible to provide an image forming apparatus which prevents poor electrical continuity in a rotating resistance heating element due to damage to the resistance heating element when a connector is attached or detached, and which suppresses poor electrical continuity when the resistance heating element is rotated. [Explanation of symbols]

[0052] 80: fixing device, 100: resistance heating element, 110: electrode portion, 200: connector, 210: contact terminal, 220: outer cover

Claims

1. a rotating resistance heating element having an electrode portion that receives power; a connector that is attached to the resistance heating element, has a contact terminal that rotates together with the resistance heating element, and supplies power to the resistance heating element via the contact terminal; and a pressing structure for pressing the contact terminal against the electrode portion after the connector is attached to the resistance heating element.

2. 2. The heating device according to claim 1, wherein the pressing structure comes into contact with the contact terminal as the pressing structure moves in one direction, and presses the contact terminal against the electrode portion.

3. The heating device according to claim 2, characterized in that a specific point of the contact terminal is provided on a path of movement of the pressing structure in one direction, the specific point coming into contact with the pressing structure as the pressing structure moves in the one direction, becoming a point of force, and pressing the electrode portion at the point of action of the contact terminal.

4. 3. The heating device according to claim 2, wherein the contact terminal is not in contact with the electrode portion before contacting the pressing structure.

5. 2. The heating device according to claim 1, wherein the pressing structure is configured to move the contact terminal in a direction intersecting the one direction by moving the pressing structure in the one direction, thereby pressing the contact terminal against the electrode portion.

6. 6. The heating device according to claim 5, wherein the one direction of the pressing structure is the same as the axial direction of the rotating resistance heating element.

7. 2. The heating device according to claim 1, wherein the contact terminal is deformed when the pressing structure presses the contact terminal against the electrode portion.

8. The heating device according to claim 7, characterized in that the contact terminal is deformed by a spring structure, with the upstream side of the one direction in which the pressing structure moves as a fulcrum, a specific point in contact with the pressing structure as a force point, and a point in contact with the electrode portion as a point of action.

9. The connector includes an outer ring that rotates with the resistance heating element; an inner ring that does not rotate together with the resistance heating element; a power supply ring provided between the outer ring and the inner ring for transferring power from the inner ring to the outer ring; The heating device according to claim 1, further comprising:

10. The heating device according to claim 9 , wherein the pressing structure is pressed into contact with the inner ring of the connector.

11. 10. The heating device according to claim 9, wherein the pressing structure is pressed into contact with the outer ring of the connector and rotates with the rotation of the outer ring.

12. 12. The heating device according to claim 9, wherein the inner ring has a cavity therein for passing a heating lamp for heating the resistance heating element.

13. 2. The heating device according to claim 1, wherein the pressing structure releases the pressing of the contact terminal against the electrode portion as the contact terminal moves in the direction opposite to the one direction.

14. The heating device according to claim 13 , wherein the pressing structure releases contact with the contact terminal as the pressing structure moves in the reverse direction, and the release of contact releases the contact terminal from the electrode portion.

15. a developer for developing the electrostatic latent image on the photoconductor; a transfer section for transferring the developed image onto a sheet of paper; a rotating resistance heating element having an electrode portion that receives power; a connector that is attached to the resistance heating element, has a contact terminal that rotates together with the resistance heating element, and supplies power to the resistance heating element via the contact terminal; a fixing device having a pressing structure for pressing the contact terminals against the electrode portions after the connector is attached to the resistance heating element, and fixing the paper on which the developed image has been transferred; An image forming apparatus comprising:

Images