Image forming apparatus

Abstract

To provide an image forming apparatus that prevents an increase in the temperature of a member arranged near a fixing device.SOLUTION: An image forming apparatus 100 comprises: a fixing device 12 that has a heat source for thermally fixing toner images formed on a sheet P; a cleaning device 9 that holds toner therein and conveys the toner held therein; and a heat blocking unit 10 that blocks heat from the fixing device 12 to the cleaning device 9. The heat blocking unit 10 has an airway 94, and a duct 93 having a cavity. The heat blocking unit 10 is arranged between the fixing device 12 and the cleaning device 9 arranged opposite to each other. The cleaning device 9, airway 94, duct 93, and fixing device 12 are arranged in this order.SELECTED DRAWING: Figure 2

Description

[Technical field]

[0001] The present disclosure relates to an image forming apparatus having a heat source. [Background technology]

[0002] Image forming devices such as copiers, facsimile machines, printers, and multifunction machines form a toner image on paper using a photoconductor drum, and then fix the toner image to the paper to form an image on the paper. Specifically, the powder toner that forms the toner image is melted by heat, and the toner image is fixed to the paper by applying pressure with a pressure roller. In addition, the fixing device is equipped with a heater, which is a heat source, and is heated to a high temperature in order to melt the toner.

[0003] In addition, since toner has a property of melting when heated, it is preferable to place devices that contain toner away from the fixing device. In other words, if the toner melts, problems will occur in devices other than the fixing device. For example, a developing device that forms a toner image on the surface of a photosensitive drum, a cleaning device that collects waste toner remaining on the surface of an intermediate transfer belt, etc. are generally placed at a position sufficiently far away from the fixing device so that they are not easily heated.

[0004] However, in recent years, as image forming devices have become smaller, the degree of freedom in arranging each component has decreased. Therefore, there are cases where a cleaning device, etc. must be arranged near the fixing device. In such cases, measures are taken, such as arranging a heat shield between the fixing device and the cleaning device, so that the inside of the cleaning device does not become hot due to the heat from the fixing device. However, there is a problem that the heat shield has a small thermal capacity and does not provide a sufficient heat insulation effect.

[0005] Therefore, in order to obtain a higher heat insulation effect, for example, Patent Document 1 discloses an image forming apparatus that can block the fixing heat of the fixing unit (fixing device) from being transmitted to the outside. According to the image forming apparatus disclosed in Patent Document 1, a cooling duct is provided around the fixing unit, and an axial fan is attached to the exhaust port of the cooling duct, and the axial fan is operated to pass air through the cooling duct, and the air removes heat and cools the device. Furthermore, the axial direction of the axial fan is tilted to match the direction of the air flow passing through the exhaust port. This prevents the exhaust efficiency of the cooling duct from decreasing, and prevents the cooling efficiency from dropping. [Prior art documents] [Patent documents]

[0006] [Patent Document 1] Japanese Patent Application Publication No. 11-65404 Summary of the Invention [Problem to be solved by the invention]

[0007] As mentioned above, since sufficient insulation effect cannot be obtained by simply installing a heat shield, the image forming apparatus disclosed in the above Patent Document 1 has been proposed. However, when the image forming apparatus is in operation for a long period of time, in particular, the amount of heat generated in the fixing device is large, and even with the image forming apparatus disclosed in the above Patent Document 1, the temperature inside the duct rises, and there is a problem that the heat cannot be sufficiently blocked.

[0008] The present disclosure has been made in consideration of the above circumstances, and has an object to provide an image forming apparatus that suppresses an increase in temperature of members disposed in the vicinity of a fixing device. [Means for solving the problem]

[0009] An image forming apparatus according to one aspect of the present disclosure is an image forming apparatus that forms a toner image on a recording medium and forms an image on the recording medium by fixing the toner image formed on the recording medium, and is characterized in that it comprises a fixing device having a heat source for thermally fixing the toner image formed on the recording medium, a toner transport device that holds toner inside and transports the held toner, and a heat shielding section that insulates heat from the fixing device to the toner transport device, wherein the heat shielding section has an air passage and a duct section having a cavity, and the heat shielding section is disposed between the fixing device and the toner transport device which are arranged opposite each other, and the toner transport device, the air passage, the duct section, and the fixing device are arranged in that order.

[0010] In this way, since the image forming apparatus includes a heat shielding portion, heat generated from the fixing device having a heat source is less likely to be transmitted to the toner conveying device. This suppresses the temperature rise of the toner conveying device, and prevents the occurrence of problems such as melting of the toner in the toner conveying device. Furthermore, since the heat shielding portion includes an air passage and a duct portion having a cavity, it is possible to more reliably inhibit the transmission of heat. In addition, even though the toner conveying device is disposed near the fixing device that generates heat, the toner conveying device is less susceptible to the heat from the fixing device. This reduces design constraints such as placing the toner conveying device and the fixing device apart, which improves design freedom and makes it possible to realize a smaller image forming apparatus.

[0011] Furthermore, in the above-described image forming apparatus, the toner transport device may be detachable from the image forming apparatus main body, and may include a first duct separation portion that is a part of the duct portion and that is detached from the image forming apparatus main body as the toner transport device is attached to or detached from the image forming apparatus main body, and the image forming apparatus main body may have a second duct separation portion that is a part of the duct portion, and the duct portion including the first duct separation portion and the second duct separation portion may be formed by attaching the toner transport device to the image forming apparatus main body.

[0012] In this way, by attaching the toner conveying device to the image forming apparatus main body, a duct section including a first duct separation section and a second duct separation section is formed, thereby making it possible to prevent the temperature of the toner conveying device from rising while saving space.

[0013] In the above-described image forming apparatus, the toner conveying device is detachable by being moved in a horizontal direction relative to the image forming apparatus main body, the first duct separation portion has a first rib arranged in a vertical direction, a second rib arranged in the vertical direction and substantially parallel to the first rib, and a bottom surface portion connecting the first rib and the second rib, the second duct separation portion has a third rib arranged in the vertical direction, a fourth rib arranged in the vertical direction and substantially parallel to the third rib, and a ceiling portion connecting the third rib and the fourth rib, and the second rib is disposed in the vertical direction relative to the first rib. The toner transport device may be disposed relative to the third rib on a side in a direction in which the toner transport device is removed from the image forming apparatus main body, and the fourth rib is disposed relative to the third rib on a side in a direction in which the toner transport device is removed from the image forming apparatus main body, the first rib and the fourth rib are disposed so as not to interfere with each other when the toner transport device is attached to the image forming apparatus main body, and when the toner transport device is attached to the image forming apparatus main body, the first rib is disposed adjacent to the third rib and the second rib is disposed adjacent to the fourth rib, thereby forming the duct portion.

[0014] This allows the toner transport device to be attached to the image forming apparatus body to form a duct section, which can be realized with a simple structure. In addition, the third and fourth ribs, which are part of the duct section, are provided on the image forming apparatus body, which improves the strength of the duct section.

[0015] In addition, in the above-mentioned image forming apparatus, the toner conveying device can be attached and detached by moving it horizontally relative to the image forming apparatus main body, the first duct separation portion has a first rib arranged in a vertical direction, a second rib arranged in a vertical direction and substantially parallel to the first rib, and a bottom surface portion connecting the first rib and the second rib, the second duct separation portion has a third rib arranged in a vertical direction and a ceiling portion extending from the third rib in a direction toward which the toner conveying device is removed from the image forming apparatus main body, the second rib is arranged on the side of the first rib in the direction toward which the toner conveying device is removed from the image forming apparatus main body, and when the toner conveying device is attached to the image forming apparatus main body, the first rib is arranged in close proximity to the third rib and the second rib is arranged in close proximity to the ceiling portion to form the duct portion.

[0016] This allows the toner transport device to be attached to the image forming apparatus body to form a duct section, which can be realized with a simple structure. In addition, the third and fourth ribs, which are part of the duct section, are provided on the image forming apparatus body, which improves the strength of the duct section.

[0017] In addition, in the above-mentioned image forming apparatus, the toner conveying device can be attached and detached by moving it horizontally relative to the image forming apparatus main body, the first duct separation portion has a first rib arranged in a vertical direction, a second rib arranged in a vertical direction and substantially parallel to the first rib, and a bottom surface portion connecting the first rib and the second rib, the second duct separation portion has a ceiling portion extending in a horizontal direction, the second rib is arranged on the side of the first rib that faces the direction in which the toner conveying device is removed from the image forming apparatus main body, and when the toner conveying device is attached to the image forming apparatus main body, each of the first rib and the second rib is arranged in close proximity to the ceiling portion to form the duct portion.

[0018] This allows the toner transport device to be attached to the image forming apparatus body to form a duct section, which can be realized with a simple structure. In addition, the third and fourth ribs, which are part of the duct section, are provided on the image forming apparatus body, which improves the strength of the duct section.

[0019] In addition, the above-mentioned image forming apparatus may be provided with an image carrier on whose surface a toner image is formed, and an endless intermediate transfer belt onto which the toner image is transferred from the image carrier to form a toner image on the recording medium, and the toner transport device may be a cleaning device for removing waste toner remaining on the intermediate transfer belt.

[0020] This prevents the waste toner in the cleaning device from melting even if the cleaning device is disposed near the fixing device. In addition, since the cleaning device can be disposed near the fixing device, the design freedom is high and the image forming device can be made smaller.

[0021] In addition, the above-mentioned image forming apparatus may include an image carrier on whose surface a toner image is formed, a developing device that supplies toner to the image carrier in order to form a toner image on the surface of the image carrier, and a developer storage device that stores a developer containing toner and supplies the developer to the developing device, and the toner transport device may be the developer storage device.

[0022] This prevents the toner contained in the developer accommodating device from melting even if the developer accommodating device is disposed near the fixing device. In addition, since the developer accommodating device can be disposed near the fixing device, the design freedom is high and the image forming device can be made smaller. Effect of the Invention

[0023] According to the present disclosure, it is possible to provide an image forming apparatus that suppresses an increase in temperature of members disposed in the vicinity of a fixing device. [Brief description of the drawings]

[0024] [Figure 1] 1 is a front view perspectively showing a schematic configuration of an image forming apparatus according to a first embodiment of the present disclosure. [Diagram 2] 1 is a front view showing a schematic configuration of a cleaning device and its periphery in an image forming apparatus according to a first embodiment of the present disclosure. [Diagram 3] FIG. 2 is a front view for explaining a method of removing a fixing device, a secondary transfer device, and an intermediate transfer belt device in the image forming apparatus according to the first embodiment of the present disclosure. [Figure 4] 1 is a front view perspectively showing a configuration around a cleaning device in an image forming apparatus according to a first embodiment of the present disclosure. [Diagram 5] 1 is a front view perspectively illustrating a configuration around a cleaning device in a state where a fixing device is removed in an image forming apparatus according to a first embodiment of the present disclosure. [Figure 6] 4 is a perspective front view showing the configuration of the periphery of the cleaning device in the image forming apparatus according to the first embodiment of the present disclosure when the intermediate transfer belt device is being removed. FIG. [Figure 7] FIG. 2 is a perspective view showing a configuration of the periphery of a cleaning device in a state where an intermediate transfer belt device is being removed in the image forming apparatus according to the first embodiment of the present disclosure. [Figure 8] 13 is a perspective front view showing a cleaning device and its surrounding configuration in an image forming apparatus according to a second embodiment of the present disclosure. FIG. [Figure 9] FIG. 11 is a perspective front view showing a cleaning device and its surrounding configuration in an image forming apparatus according to a third embodiment of the present disclosure. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0025] DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS An embodiment of the present disclosure will be described with reference to the drawings.

[0026] (First embodiment) An image forming apparatus according to a first embodiment of the present disclosure will be described with reference to the drawings. Fig. 1 is a perspective front view showing a schematic configuration of the image forming apparatus according to the first embodiment of the present disclosure.

[0027] In the coordinates shown in the following figures, the X-axis direction indicates the left-right direction (horizontal direction) when the image forming apparatus 100 is viewed from the front, and the positive and negative X-axis directions indicate the left and right sides, respectively. The Y-axis direction indicates the depth direction (front-rear direction) perpendicular to the X-axis, which is the left-right direction, and the positive and negative Y-axis directions indicate the operation side (front side) and the rear side, which is the opposite side to the operation side, respectively. The Z-axis direction indicates the up-down direction, that is, the vertical direction, and the positive and negative Z-axis directions indicate the upper and lower sides, respectively. Note that when the image forming apparatus 100 is not shown and only the components of the image forming apparatus 100 are illustrated, the coordinates are shown when the components are incorporated in the image forming apparatus 100.

[0028] The image forming apparatus 100 is a multifunction machine having a copy function, a scanner function, a facsimile function, and a printer function, and forms an image of an original G read by an image reading device 102 or an image received from an external source in color or monochrome on a sheet P such as paper. The image forming apparatus 100 also transmits the image of an original G read by the image reading device 102 to the outside.

[0029] An original feeder 160 (automatic document feeder (ADF)) is provided above the image reading unit 130 and is supported so as to be openable and closable relative to the image reading unit 130, and the image reading device 102 is equipped with the original feeder 160. The original feeder 160 transports one or more originals G one by one. The image reading device 102 reads the originals G transported by the original feeder 160 one by one out of the one or more originals G.

[0030] The image reading device 102 includes a document placement table 130a and a document reading function for reading a document G placed on the document placement table 130a. When the document feeder 160 of the image forming device 100 is opened, the document placement table 130a above the image reading unit 130 is opened, and the document G can be manually placed on the document placement table 130a. The document feeder 160 also includes a document placement tray 161 on which the document G is placed, and a document discharge tray 162 on which the document G discharged to the outside is stacked.

[0031] The image reading device 102 has a transported document reading function for reading the document G transported by the document feeding device 160. The document feeding device 160 transports the document G placed on the document placement tray 161 onto the document reading section 130b in the image reading unit 130. The image reading unit 130 scans the scanning optical system 130c to read the document placed on the document placement table 130a or reads the document G transported by the document feeding device 160 to generate image data.

[0032] The image forming apparatus main body 101 includes an image transfer section 50, an optical scanning device 1, an intermediate transfer belt device 70, a secondary transfer device 11, a fixing device 12, a sheet transport path S, a paper feed cassette 18, and a sheet discharge tray 141.

[0033] The image forming apparatus 100 handles image data corresponding to a color image using the colors black (K), cyan (C), magenta (M), and yellow (Y), or a monochrome image using a single color (e.g., black).

[0034] The image transfer unit 50 of the image forming apparatus 100 has four image stations Pa, Pb, Pc, Pd corresponding to the colors black, cyan, magenta, and yellow. Each of the image stations Pa, Pb, Pc, Pd includes a developing device 2, a photoconductor drum 3, a drum cleaning device 4, and a charger 5, and four types of toner images are formed by the image stations Pa, Pb, Pc, Pd. In other words, four each of the developing devices 2, photoconductor drums 3, drum cleaning devices 4, and chargers 5 are provided, each corresponding to black, cyan, magenta, and yellow.

[0035] The image forming apparatus 100 also has toner cartridges 21 corresponding to the four image stations Pa, Pb, Pc, and Pd. The toner cartridges 21 are developer containing devices that contain developer containing toner of the corresponding color, and supply developer containing toner to the corresponding developing device 2. The toner cartridges 21 are located above the developing device 2.

[0036] The optical scanning device 1 exposes the surface of the photoreceptor drum 3 to light to form an electrostatic latent image. The developing device 2 develops the electrostatic latent image on the surface of the photoreceptor drum 3 to form a toner image on the surface of the photoreceptor drum 3. The drum cleaning device 4 removes and collects residual toner on the surface of the photoreceptor drum 3. The charger 5 uniformly charges the surface of the photoreceptor drum 3 to a predetermined potential. Through the series of operations described above, a toner image of each color is formed on the surface of each photoreceptor drum 3.

[0037] The intermediate transfer belt device 70 includes an intermediate transfer roller 6, an endless intermediate transfer belt 71, an intermediate transfer driving roller 72, an intermediate transfer driven roller 73, and a cleaning device 9. The intermediate transfer belt 71 is an endless belt that can rotate, and is wound around the intermediate transfer driving roller 72 and the intermediate transfer driven roller 73. In other words, the intermediate transfer belt 71 is stretched around the intermediate transfer driving roller 72 and the intermediate transfer driven roller 73. Four intermediate transfer rollers 6 are provided inside the intermediate transfer belt 71 so as to form four types of toner images corresponding to the respective colors. The intermediate transfer rollers 6 transfer the toner images of the respective colors formed on the surfaces of the photosensitive drums 3 to the intermediate transfer belt 71.

[0038] The image forming apparatus 100 sequentially transfers and superimposes the toner images of each color formed on the surface of each photosensitive drum 3, forming a color toner image on the surface of an intermediate transfer belt 71 that is stretched around an intermediate transfer driving roller 72 and an intermediate transfer driven roller 73. The toner images formed on the intermediate transfer belt 71 are transferred to a sheet P by a secondary transfer device 11. Here, a portion of the toner images formed on the intermediate transfer belt 71 is not transferred to the sheet P and remains on the surface of the intermediate transfer belt 71 as waste toner, and this waste toner is removed and collected by a cleaning device 9.

[0039] The cleaning device 9 removes waste toner remaining on the surface of the intermediate transfer belt 71, and is disposed near the fixing device 12. The cleaning device 9 includes a cleaning blade 91 that removes waste toner remaining on the surface of the intermediate transfer belt 71, and a waste toner transport screw 92 that transports the removed waste toner. The cleaning blade 91 is fixedly disposed in contact with the intermediate transfer belt 71, and scrapes off waste toner remaining on the surface of the intermediate transfer belt 71 as the intermediate transfer belt 71 drives. The waste toner scraped off from the surface of the intermediate transfer belt 71 by the cleaning blade 91 is transported by the waste toner transport screw 92 that is driven to rotate, and is sent to a waste toner storage unit (not shown).

[0040] As will be described later in detail, a heat shielding section 10 that inhibits the transfer of heat is provided adjacent to the cleaning device 9. The heat shielding section 10 includes an air passage 94 and a duct 93. Specifically, the air passage 94 is arranged so as to surround the waste toner transport screw 92 of the cleaning device 9 (see FIG. 2). The provision of the air passage 94 prevents the waste toner transport screw 92 from increasing in temperature even if heat is transferred from the outside. Furthermore, the hollow duct 93 is arranged on the fixing device 12 side with respect to the waste toner transport screw 92 of the cleaning device 9. The duct 93 has a shape that extends along the front-rear direction (Y-axis direction). This can block heat from the fixing device 12 and suppress the temperature increase of the waste toner transport screw 92 (cleaning device 9).

[0041] The secondary transfer device 11 forms a transfer nip area TN between the secondary transfer roller 11a and the intermediate transfer belt 71, and conveys a sheet P conveyed through a sheet conveying path S by pinching it in the transfer nip area TN. When the sheet P passes through the transfer nip area TN, the toner image on the surface of the intermediate transfer belt 71 is transferred to the sheet P, and the sheet P is conveyed to the fixing device 12.

[0042] The fixing device 12 includes a fixing roller 31 and a pressure roller 32 that rotate while sandwiching the sheet P. The fixing device 12 sandwiches the sheet P, on which the toner image has been transferred, between the fixing roller 31 and the pressure roller 32 and applies heat and pressure to fix the toner image to the sheet P. Although not shown, a heater serving as a heat source is disposed inside the fixing roller 31, and the surface of the fixing roller 31 that comes into contact with the sheet P on which the toner image has been transferred is heated by the heat generated by the heater.

[0043] The paper feed cassette 18 is a cassette for storing sheets P used for image formation, and is provided below the optical scanning device 1. The sheet P is pulled out from the paper feed cassette 18 by a pickup roller 16 and conveyed to a sheet conveying path S. The sheet P conveyed to the sheet conveying path S is conveyed to a discharge roller 17 via a secondary transfer device 11 and a fixing device 12, and is discharged to a sheet discharge tray 141 in a discharge section 140. A conveying roller 13, a registration roller 14, and a discharge roller 17 are arranged on the sheet conveying path S. The conveying roller 13 promotes the conveyance of the sheet P. The registration roller 14 stops the sheet P once and aligns the leading edge of the sheet P. Furthermore, the registration roller 14 conveys the stopped sheet P in accordance with the timing of the color toner image on the intermediate transfer belt 71. The color toner image on the intermediate transfer belt 71 is transferred to the sheet P in a transfer nip area TN between the intermediate transfer belt 71 and the secondary transfer roller 11a.

[0044] In FIG. 1, the number of sheet feed cassettes 18 is one, but the present invention is not limited to this. A configuration may be provided in which a plurality of sheet feed cassettes 18 are provided to stack different types of sheets P, respectively.

[0045] Furthermore, when forming an image on the back side of the sheet P in addition to the front side, the image forming apparatus 100 conveys the sheet P in the reverse direction from the discharge rollers 17 to a sheet inversion path Sr. The image forming apparatus 100 inverts the sheet P conveyed in the reverse direction and guides it again to the registration rollers 14. The image forming apparatus 100 also forms an image on the back side of the sheet P guided to the registration rollers 14 in the same manner as on the front side, and conveys the sheet P to the sheet discharge tray 141.

[0046] Next, the configuration of the cleaning device 9 and its surroundings will be described in detail with reference to the drawings. Fig. 2 is a front view showing a schematic configuration of the cleaning device and its surroundings in the image forming apparatus according to the first embodiment of the present disclosure.

[0047] As described above, the cleaning device 9 includes a cleaning blade 91 that scrapes off waste toner remaining on the surface of the intermediate transfer belt 71 as the intermediate transfer belt 71 is driven, and a waste toner transport screw 92 that transports the scraped off waste toner in a direction along the Y axis (front-rear direction). The waste toner transport screw 92 transports the waste toner, for example, to the rear side (rear side), which is the negative direction of the Y axis. An end of the waste toner transport screw 92 is connected to a waste toner storage unit (not shown), and the waste toner is stored in the storage unit.

[0048] Furthermore, as shown in Fig. 2, a heat shielding section 10 is provided adjacent to the cleaning device 9. The heat shielding section 10 includes an air passage 94 and a duct 93. Although not shown in Fig. 2, the cleaning device 9 is disposed facing the fixing device 12. Specifically, the heat shielding section 10 (air passage 94, duct 93) is disposed between the cleaning device 9 and the fixing device 12. The cleaning device 9, the air passage 94, the duct 93, and the fixing device 12 are disposed in this order (see Fig. 4).

[0049] The ventilation passage 94 is formed so as to surround the waste toner transport screw 92. The ventilation passage 94 has a semicircular recess, and the waste toner transport screw 92 is configured to fit into the recess. The ventilation passage 94 is a space surrounded by the upper outer wall rib 87, the third rib 83, the first rib 81, the lower outer wall rib 86, etc., and is formed to extend in the direction along the Y axis (front-rear direction). A fan (not shown) blows air into the ventilation passage 94. For example, the air flows from the front side (front side) which is the Y axis positive direction side to the back side (rear side) which is the Y axis negative direction side. In this way, the ventilation passage 94 arranged so as to surround the waste toner transport screw 92 is hollow, and air flows through it, so that heat from the fixing device 12 is blocked, and the rise in temperature around the waste toner transport screw 92 is suppressed. Moreover, ventilation passage 94 may take in air from outside image forming apparatus 100 from the upper part of the front side by the fan and let it flow to the rear side. In this way, by taking in outside air that is relatively lower in temperature than the inside of image forming apparatus body 101, the heat shielding effect of ventilation passage 94 can be improved.

[0050] Further, a duct 93 is formed on the fixing device 12 side (X-axis negative direction side) of the ventilation passage 94. The duct 93 is a space surrounded by the first rib 81, the bottom surface portion 95, the second rib 82, the fourth rib 84, the ceiling portion 96, the third rib 83, etc., and is formed to extend in the direction along the Y-axis (front-rear direction). In this way, the hollow duct 93 and the hollow ventilation passage 94 through which air flows are installed between the fixing device 12 and the waste toner transport screw 92, so that the heat from the fixing device 12 to the waste toner transport screw 92 is sufficiently blocked. In other words, the temperature rise of the waste toner transport screw 92 is sufficiently suppressed.

[0051] The above-mentioned third rib 83, fourth rib 84 and upper outer wall rib 87 are all plate-shaped and extend from the upper side to the lower side, and further extend in the front-rear direction. These are fixedly installed on the image forming apparatus main body 101. That is, the third rib 83, the fourth rib 84 and the upper outer wall rib 87 are plate-shaped and substantially parallel to the YZ plane. The third rib 83 and the fourth rib 84 are connected by a ceiling portion 96 and installed at a predetermined distance apart. The third rib 83 and the fourth rib 84 extend downward from the ceiling portion 96 in the negative direction of the Z axis. The ceiling portion 96 is also fixedly installed on the image forming apparatus main body 101.

[0052] The first rib 81 and the second rib 82 are both plate-shaped and extend from the lower side to the upper side, and further extend in the front-rear direction. That is, the first rib 81 and the second rib 82 are plate-shaped and substantially parallel to the YZ plane. The first rib 81 and the second rib 8 are connected by a bottom surface portion 95 and are installed at a predetermined distance apart. The first rib 81 and the second rib 82 are shaped to extend from the bottom surface portion 95 toward the upper side, which is the positive direction of the Z axis. The lower outer wall rib 86 is inclined with respect to the first rib 81 and the second rib 82, but is also plate-shaped and extends from the lower side to the upper side, and further extends in the front-rear direction, like the first rib 81 and the second rib 82. That is, it is a plate-shaped configuration inclined with respect to the YZ plane.

[0053] Here, the first rib 81 and the third rib 83, the second rib 82 and the fourth rib 84 are arranged close to each other at their ends to form a duct 93. It is preferable that the first rib 81 and the third rib 83, the second rib 82 and the fourth rib 84 abut each other at their ends, but as shown in FIG. 2, they may be arranged close to each other. The lower outer wall rib 86 and the upper outer wall rib 87, the first rib 81 and the third rib 83 are arranged close to each other at their ends to form a ventilation passage 94. It is preferable that the lower outer wall rib 86 and the upper outer wall rib 87, the first rib 81 and the third rib 83 abut each other at their ends, but as shown in FIG. 2, they may be arranged close to each other.

[0054] Although the details will be described later, in the image forming apparatus 100, the intermediate transfer belt device 70 can be removed from the image forming apparatus main body 101, but even in that case, the third rib 83, the fourth rib 84, the ceiling portion 96, and the upper outer wall rib 87 are fixedly installed in the image forming apparatus main body 101 and do not move. In contrast, when the intermediate transfer belt device 70 is removed from the image forming apparatus main body 101, the first rib 81, the second rib 82, and the lower outer wall rib 86 move together with the intermediate transfer belt device 70 and the cleaning blade 91 provided on the intermediate transfer belt device 70. Here, the state shown in FIG. 2 is a state in which the intermediate transfer belt device 70 is attached to the image forming apparatus main body 101, and in this case, the duct 93 and the ventilation passage 94 are formed. However, when the intermediate transfer belt device 70 is removed from the image forming apparatus main body 101, the duct 93 and the ventilation passage 94 are not separated from each other and are not formed.

[0055] Next, a procedure for removing the intermediate transfer belt device 70 from the image forming apparatus main body 101 will be described with reference to the drawings. FIG. 3 is a front view for explaining a method for removing the fixing device, the secondary transfer device, and the intermediate transfer belt device in the image forming apparatus according to the first embodiment of the present disclosure. FIG. 4 is a front view showing a perspective view of the configuration around the cleaning device in the image forming apparatus according to the first embodiment of the present disclosure. FIG. 5 is a front view showing a perspective view of the configuration around the cleaning device in a state where the fixing device is removed in the image forming apparatus according to the first embodiment of the present disclosure. FIG. 6 is a front view showing a perspective view of the configuration around the cleaning device in the middle of removing the intermediate transfer belt device in the image forming apparatus according to the first embodiment of the present disclosure. FIG. 7 is a perspective view showing a perspective view of the configuration around the cleaning device in the middle of removing the intermediate transfer belt device in the image forming apparatus according to the first embodiment of the present disclosure.

[0056] As shown in Fig. 3, an openable main body door 101a is provided on the right side surface of the image forming apparatus main body 101. As shown in Fig. 3, the main body door 101a can be opened with its lower end as a rotation axis, and by opening the main body door 101a, the inside of the image forming apparatus main body 101 is exposed, and the fixing device 12, secondary transfer device 11, and intermediate transfer belt device 70 installed in the image forming apparatus main body 101 can be removed from the image forming apparatus main body 101 by sliding them to the right (negative direction of the X-axis).

[0057] In terms of the order of removal, the fixing device 12 is removed first, and then the secondary transfer device 11 and the intermediate transfer belt device 70 can be removed as a unit. Although not shown, the cleaning device 9 is included in the intermediate transfer belt device 70. However, since the third rib 83, the fourth rib 84, the ceiling portion 96, and the upper outer wall rib 87 are fixedly installed in the image forming apparatus main body 101 as described above, when removing the intermediate transfer belt device 70 including the cleaning device 9, the third rib 83, the fourth rib 84, the ceiling portion 96, and the upper outer wall rib 87 cannot be removed from the image forming apparatus main body 101. However, when removing the intermediate transfer belt device 70 including the cleaning device 9 from the image forming apparatus main body 101 or when installing it, when moving these, the first rib 81, the second rib 82, the bottom portion 95, and the lower outer wall rib 86 also move with these movements.

[0058] 4, in a normal image forming apparatus main body 101 before removing the fixing device 12, the secondary transfer device 11, and the intermediate transfer belt device 70, the secondary transfer device 11 is disposed on the right side of the intermediate transfer belt device 70 including the cleaning device 9, and the secondary transfer roller 11a is disposed near the intermediate transfer drive roller 72. In addition, the fixing device 12 including the fixing roller 31 having a heater therein as a heat source is disposed on the upper right side of the cleaning device 9, and a duct 93 and a ventilation passage 94 through which air flows are disposed between the waste toner conveying screw 92 and the fixing roller 31. As described above, since the duct 93 and the ventilation passage 94 are provided, the temperature rise of the waste toner conveying screw 92 due to the heat generated by the fixing roller 31 is suppressed.

[0059] The duct 93 is configured by forming a cavity by arranging the ends of the first rib 81 and the third rib 83 in close proximity to each other and by arranging the ends of the second rib 82 and the fourth rib 84 in close proximity to each other. The ventilation passage 94 is configured by forming a cavity by arranging the ends of the first rib 81 and the third rib 83 in close proximity to each other and by arranging the ends of the lower outer wall rib 86 and the upper outer wall rib 87 in close proximity to each other. A fan (not shown) sends air into the ventilation passage 94, and an air flow occurs within the ventilation passage 94 from the front side to the rear side.

[0060] When removing the fixing device 12, the secondary transfer device 11, and the intermediate transfer belt device 70 from the image forming apparatus main body 101, the main body door 101a installed on the right side of the image forming apparatus main body 101 in Fig. 4 is opened. Then, first, the fixing device 12 is slid to the right side to be removed from the image forming apparatus main body 101. This results in the state shown in Fig. 5.

[0061] 5 shows a state in which the main body door 101a is open and the fixing device 12 is removed. From this state, the integrated secondary transfer device 11 and intermediate transfer belt device 70 are further slid to the right to reach the state shown in FIG.

[0062] 6, when the integrated secondary transfer device 11 and intermediate transfer belt device 70 are slid to the right, the third rib 83, the fourth rib 84, the ceiling portion 96, and the upper outer wall rib 87 do not move, and the cleaning blade 91, the waste toner transport screw 92, the first rib 81, the second rib 82, the bottom portion 95, and the lower outer wall rib 86 move to the right. Note that the arrangement and vertical length of the first rib 81 and the fourth rib 84 are set so that they do not interfere with each other at this time.

[0063] 7 also shows a state in which the integrated secondary transfer device 11 and intermediate transfer belt device 70 are slid to the right. However, in FIG. 7, the secondary transfer device 11 and intermediate transfer belt device 70 are slid to the right less than in FIG. 6.

[0064] In this manner, in the image forming apparatus 100, when the intermediate transfer belt device 70 is attached to the image forming apparatus main body 101, the duct 93 and the ventilation passage 94, which are the heat shielding section 10, are formed adjacent to the cleaning device 9, but when the intermediate transfer belt device 70 is removed from the image forming apparatus main body 101, the duct 93 and the ventilation passage 94 are separated and no longer constitute these.

[0065] In order to mount the intermediate transfer belt device 70, secondary transfer device 11, and fixing device 12 removed from the image forming apparatus main body 101 back into the image forming apparatus main body 101 and return the image forming apparatus 100 to a normal state in which it can be operated, the above-mentioned steps of removing them can be carried out in reverse. That is, with the main body door 101a of the image forming apparatus main body 101 open, first, the intermediate transfer belt device 70 and secondary transfer device 11, which are integrated together, are inserted from the right side (negative direction of the X-axis) of the image forming apparatus main body 101, and then slid to the left side (positive direction of the X-axis) to move them into the image forming apparatus main body 101 (see FIGS. 6 and 7).

[0066] By mounting the intermediate transfer belt device 70 on the image forming apparatus main body 101, the first rib 81, the second rib 82 and the lower outer wall rib 86 are disposed adjacent to the third rib 83, the fourth rib 84 and the upper outer wall rib 87 fixedly disposed on the image forming apparatus main body 101, respectively, thereby forming a duct 93 and a ventilation passage 94 (see FIG. 5). As described above, from the viewpoint of the airtightness of the duct 93 and the ventilation passage 94, it is preferable that the third rib 83, the fourth rib 84 and the upper outer wall rib 87 are in contact with the first rib 81, the second rib 82 and the lower outer wall rib 86, respectively. However, when the intermediate transfer belt device 70 is attached to the image forming apparatus main body 101, it is sufficient that the duct 93 and the ventilation passage 94 are formed by arranging the third rib 83, the fourth rib 84, and the upper outer wall rib 87 in close proximity to the first rib 81, the second rib 82, and the lower outer wall rib 86, respectively.

[0067] After the intermediate transfer belt device 70 and the secondary transfer device 11 are mounted in the image forming apparatus main body 101, the fixing device 12 is inserted from the right side (negative side of the X-axis) of the image forming apparatus main body 101, and slid toward the left side (positive side of the X-axis) to move it into the image forming apparatus main body 101 and mounted therein, and the main body door 101a is closed (see FIG. 4). This completes the mounting of the intermediate transfer belt device 70, the secondary transfer device 11, and the fixing device 12.

[0068] According to the image forming apparatus 100 of the first embodiment, as described above, the duct 93 and the ventilation passage 94 are provided, so that even if the cleaning device 9 is disposed near the fixing device 12 having a heat source, the cleaning device 9 is unlikely to be affected by heat from the fixing device 12. Therefore, the cleaning device 9 can prevent a problem that the waste toner removed from the intermediate transfer belt 71 melts in the cleaning device 9 due to heat.

[0069] Furthermore, since the cleaning device 9 is not easily affected by heat from the fixing device 12 even if it is disposed near the fixing device 12, there is no need to install the cleaning device 9 at a position distant from the fixing device 12, improving design freedom and thereby realizing space saving for the image forming apparatus 100. Furthermore, the duct 93 and the ventilation passage 94 are composed of a plurality of members, and the duct 93 and the ventilation passage 94 are formed by mounting the intermediate transfer belt device 70 to the image forming apparatus main body 101, further improving design freedom.

[0070] Furthermore, since duct 93 is provided, a sufficient heat insulating effect can be obtained even if the amount of air sent into ventilation passage 94 is reduced. Therefore, the operation of the fan that sends air into ventilation passage 94 can be suppressed.

[0071] In addition, since the third rib 83 and the fourth rib 84 fixedly installed on the image forming apparatus body 101 are part of the components of the duct 93 and the ventilation passage 94, there is also an effect that the strength of the duct 93 and the ventilation passage 94 is high. Second embodiment In the image forming apparatus according to the second embodiment of the present disclosure, the members constituting the duct 93 and the ventilation passage 94 are different from those of the image forming apparatus 100 according to the first embodiment, but the other configurations are similar to those of the image forming apparatus 100 according to the first embodiment. Therefore, the points that are different from the first embodiment will be described. Also, the same reference numerals are used to denote the same members as those of the first embodiment, and the description thereof will be omitted.

[0072] An image forming apparatus according to a second embodiment of the present disclosure will be described with reference to the drawings. Fig. 8 is a perspective front view showing a cleaning device and its surrounding configuration in the image forming apparatus according to the second embodiment of the present disclosure.

[0073] 8, in the second embodiment, the fourth rib 84 that was provided in the first embodiment is not provided. In addition, the second rib 82a connected to the first rib 81 by the bottom surface portion 95 extends toward the upper side and is disposed adjacent to the right end portion of the ceiling portion 96. With this configuration, the duct 93 is configured to include the first rib 81, the bottom surface portion 95, the second rib 82a, the ceiling portion 96, and the third rib 83. Third embodiment The image forming apparatus according to the third embodiment of the present disclosure differs from the image forming apparatus 100 according to the first embodiment in the components constituting the duct 93 and the ventilation passage 94, but the other components are similar to those of the image forming apparatus 100 according to the first embodiment. Therefore, the differences from the first embodiment will be described. Also, the same reference numerals will be used to denote the same components as those in the first embodiment, and description thereof will be omitted.

[0074] An image forming apparatus according to a third embodiment of the present disclosure will be described with reference to the drawings. Fig. 9 is a perspective front view showing a cleaning device and its surrounding configuration in the image forming apparatus according to the third embodiment of the present disclosure.

[0075] 9, in the third embodiment, the third rib 83 and the fourth rib 84 that are provided in the first embodiment are not provided. In addition, the first rib 81a and the second rib 82a, which are connected by the bottom surface portion 95 and extend upward, both extend upward and are disposed adjacent to the lower surface portion and the right end portion of the ceiling portion 96. Due to this configuration, the duct 93 is configured to include the first rib 81a, the bottom surface portion 95, the second rib 82a, and the ceiling portion 96.

[0076] As described above, according to the image forming apparatus 100 of the first to third embodiments, the duct 93 and the ventilation passage 94, which are the heat shielding portion 10, are provided, so that even if the cleaning device 9 is disposed near the fixing device 12 having a heat source, the cleaning device 9 is not easily affected by the heat from the fixing device 12. Therefore, the cleaning device 9 can prevent the waste toner removed from the intermediate transfer belt 71 from melting due to heat in the cleaning device 9. Therefore, the cleaning device 9 does not need to be installed at a position away from the fixing device 12, and the degree of freedom in design is improved, so that the space saving of the image forming apparatus 100 can be realized. In addition, the duct 93 and the ventilation passage 94 are composed of a plurality of members, and the duct 93 and the ventilation passage 94 are formed by mounting the intermediate transfer belt device 70 to the image forming apparatus main body 101, so that the degree of freedom in design is further improved.

[0077] In addition, according to the image forming apparatus 100 of the first to third embodiments, the duct 93 and the ventilation passage 94, which are the heat shielding portion 10, are provided between the cleaning device 9 and the fixing device 12. However, if the fixing device 12 is arranged near a device that holds and conveys toner inside other than the cleaning device 9, the duct 93 and the ventilation passage 94 may be provided between them. For example, in the image forming apparatus 100, when the cleaning device 9 is located near the intermediate transfer driven roller 73 instead of the configuration shown in FIG. 1, the toner cartridge 21 may be extended toward the fixing device 12 and disposed near the fixing device 12 for the purpose of increasing the capacity of the toner cartridge 21, and in such a case, the duct 93 and the ventilation passage 94 may be provided between the fixing device 12 and the toner cartridge 21.

[0078] The present disclosure is not limited to the above-described embodiments, and can be implemented in various other forms. Therefore, the embodiments are merely illustrative in all respects and should not be interpreted as being limited. The scope of the present disclosure is indicated by the claims, and is not limited in any way by the text of the specification. Furthermore, all modifications and changes within the scope of the claims are within the scope of the present disclosure. [Explanation of symbols]

[0079] 1 Optical scanning device 2. Developing device 3. Photoconductor drum (image carrier) 4 Drum cleaning device 5. Charger 6 Intermediate transfer roller 9 Cleaning device (toner transport device) 10 Heat shield 11 Secondary transfer device 11a Secondary transfer roller 12 Fixing device 13 Conveyor roller 14 Registration roller 16 Pickup roller 17 Discharge roller 18 Paper feed cassette 21 Toner cartridge (developer storage device, toner transport device) 31 Fuser roller 32 Pressure roller 70 Intermediate transfer belt device 71 Intermediate transfer belt 72 Intermediate transfer drive roller 73 Intermediate transfer driven roller 81, 81a First rib (first duct separation part) 82, 82a Second rib (first duct separation part) 83 3rd rib (2nd duct separation part) 84 4th rib (2nd duct separation part) 86 Lower exterior wall rib 87 Upper exterior wall rib 91 Cleaning blade 92 Waste toner transport screw 93 Duct (Duct section) 94 Ventilation duct 95 Bottom section (first duct separation section) 96 Ceiling section (second duct separation section) 101a Main unit door 100 Image forming device 101 Image forming apparatus main body 102 Image reading device 130 Reading unit 130a Document stand 130b Document reading section 131 Scanning Optical System 140 Discharge section 141 Sheet output tray 160 Document feeder 161 Document tray 162 Document output tray G Manuscript P sheet (recording medium) Pa, Pb, Pc, Pd Imaging Station S Sheet transport path Sr sheet inversion pathway TN Transfer nip area

Claims

1. An image forming apparatus for forming a toner image on a recording medium and fixing the toner image formed on the recording medium, the image forming apparatus comprising: a fixing device having a heat source for thermally fixing the toner image formed on the recording medium; a toner conveying device that holds the toner therein and conveys the held toner; a heat insulating section that insulates the toner conveying device from heat from the fixing device, The heat shielding portion has a ventilation passage and a duct portion having a cavity, the heat shield is disposed between the fixing device and the toner transport device which are disposed opposite to each other, an image forming apparatus, characterized in that the toner transport device, the ventilation passage, the duct portion, and the fixing device are arranged in this order.

2. 2. The image forming apparatus according to claim 1, the toner transport device is detachable from the main body of the image forming apparatus; a first duct separation portion that is a part of the duct portion and that is detached from the image forming apparatus main body when the toner conveying device is attached to or detached from the image forming apparatus main body; the image forming apparatus main body has a second duct separation portion which is a part of the duct portion, an image forming apparatus, wherein the duct portion including the first duct separation portion and the second duct separation portion is configured by mounting the toner transport device to the image forming apparatus main body;

3. 3. The image forming apparatus according to claim 2, the toner transport device is detachable by being moved horizontally relative to the image forming apparatus body, the first duct separation portion has a first rib arranged in a vertical direction, a second rib arranged in the vertical direction and substantially parallel to the first rib, and a bottom surface portion connecting the first rib and the second rib, the second duct separation portion includes a third rib arranged in a vertical direction, a fourth rib arranged in a vertical direction and substantially parallel to the third rib, and a ceiling portion connecting the third rib and the fourth rib, the second rib is disposed on a side of the first rib in a direction in which the toner transport device is removed from the image forming apparatus main body, the fourth rib is disposed on a side of the third rib in a direction in which the toner transport device is removed from the image forming apparatus main body, the first rib and the fourth rib are disposed so as not to interfere with each other when the toner transport device is attached to the image forming apparatus main body, an image forming apparatus characterized in that, when the toner conveying device is attached to the image forming apparatus main body, the first rib is positioned adjacent to the third rib and the second rib is positioned adjacent to the fourth rib, thereby forming the duct portion.

4. 3. The image forming apparatus according to claim 2, the toner transport device is detachable by being moved horizontally relative to the image forming apparatus body, the first duct separation portion has a first rib arranged in a vertical direction, a second rib arranged in the vertical direction and substantially parallel to the first rib, and a bottom surface portion connecting the first rib and the second rib, the second duct separation portion has a third rib disposed in a vertical direction, and a ceiling portion extending from the third rib in a direction toward which the toner conveying device is removed from the image forming apparatus main body, the second rib is disposed on a side of the first rib in a direction in which the toner transport device is removed from the image forming apparatus main body, an image forming apparatus characterized in that, when the toner conveying device is attached to the image forming apparatus main body, the first rib is positioned adjacent to the third rib, and the second rib is positioned adjacent to the ceiling portion, thereby forming the duct portion.

5. 3. The image forming apparatus according to claim 2, the toner transport device is detachable by being moved horizontally relative to the image forming apparatus body, the first duct separation portion has a first rib arranged in a vertical direction, a second rib arranged in the vertical direction and substantially parallel to the first rib, and a bottom surface portion connecting the first rib and the second rib, The second duct separation portion has a ceiling portion extending in a horizontal direction, the second rib is disposed on a side of the first rib in a direction in which the toner transport device is removed from the image forming apparatus main body, An image forming apparatus characterized in that, when the toner conveying device is attached to the image forming apparatus main body, the first rib and the second rib are each positioned adjacent to the ceiling portion to form the duct portion.

6. 6. The image forming apparatus according to claim 1, an image carrier on whose surface a toner image is formed; an endless intermediate transfer belt onto which a toner image is transferred from the image carrier and which forms a toner image on the recording medium; 2. The image forming apparatus according to claim 1, wherein the toner transport device is a cleaning device for removing waste toner remaining on the intermediate transfer belt.

7. 6. The image forming apparatus according to claim 1, an image carrier on whose surface a toner image is formed; a developing device that supplies toner to the image carrier to form a toner image on the surface of the image carrier; a developer storage device that stores a developer including a toner and supplies the developer to the developing device; The toner transport device is the developer storage device.

Images