Image forming apparatus

Abstract

To suppress a decrease in visibility in a case where a fixing section is drawn out from an apparatus main body while maintaining cooling efficiency for the fixing section in comparison with a case where a fixing unit that is attachable to and detachable from the apparatus main body is provided with a plurality of ducts.SOLUTION: An image forming apparatus includes: an apparatus main body that has an image forming section for forming an image on a recording material; a fixing unit that has a fixing section for fixing the image formed by the image forming section onto the recording material and that is attachable to and detachable from the apparatus main body; a first duct that is attached to the fixing unit to face the fixing section and through which a gas for cooling the fixing section flows; and a second duct that is attached to the apparatus main body to be adjacent to the first duct and through which the gas for cooling the fixing section flows.SELECTED DRAWING: Figure 3

Description

Technical Field

[0001] The present invention relates to an image forming apparatus.

Background Art

[0002] Patent Document 1 discloses a technique for improving the cooling efficiency of an image forming unit by providing a ventilation duct in a space sandwiched between the image forming unit and the fixing unit, and connecting an intake duct and an exhaust duct to a side surface of the ventilation duct opposite to the paper conveyance path to increase the ventilation amount of the ventilation duct.

Prior Art Documents

Patent Documents

[0003]

Patent Document 1

Summary of the Invention

Problems to be Solved by the Invention

[0004] As a method for improving the cooling efficiency of a fixing unit provided in a fixing unit detachable from the apparatus main body, it is conceivable to provide a plurality of ducts in the fixing unit. However, when a plurality of ducts are provided in the fixing unit, for example, when a recording material is jammed in the fixing unit and the fixing unit is pulled out from the apparatus main body, the visibility of the recording material in the fixing unit is likely to decrease. An object of the present invention is to suppress a decrease in visibility when the fixing unit is pulled out from the apparatus main body while maintaining the cooling efficiency of the fixing unit as compared with the case where a plurality of ducts are provided in a fixing unit detachable from the apparatus main body.

Means for Solving the Problems

[0005] The invention of claim 1 is an image forming apparatus comprising: an apparatus body having an image forming unit for forming an image on a recording material; a fixing unit having a fixing unit for fixing the image formed by the image forming unit to the recording material, and detachably attached to the apparatus body; a first duct attached to the fixing unit so as to face the fixing unit and through which gas for cooling the fixing unit flows; and a second duct attached to the apparatus body so as to be adjacent to the first duct and through which gas for cooling the fixing unit flows, wherein the space through which gas flows in the first duct and the space through which gas flows in the second duct are formed by independent and different surfaces. The invention of claim 2 comprises an apparatus body having an image forming unit for forming an image on a recording material, a fixing unit having a fixing unit for fixing the image formed by the image forming unit to the recording material and being detachable from the apparatus body, a first duct attached to the fixing unit so as to face the fixing unit and through which gas for cooling the fixing unit flows, and a second duct attached to the apparatus body so as to be adjacent to the first duct and through which gas for cooling the fixing unit flows, the second of The duct is attached to the main body of the apparatus so as to be adjacent to the first duct on the upstream side in the transport direction of the recording material being transported to the fixing unit, and is an image forming apparatus having an air intake port that draws in air from between the fixing unit and the image forming unit. The invention of claim 3 is an image forming apparatus according to claim 3, characterized in that the second duct is provided above the fixing portion in the direction of gravity, and the intake port faces downward in the direction of gravity. The invention of claim 4 is an image forming apparatus according to claim 3 or 4, wherein the fixing unit further comprises a shielding portion that shields the space between the fixing portion and the image forming portion, and the intake port of the second duct draws in air from the image forming portion side rather than the shielding portion. The invention of claim 5 is an image forming apparatus comprising: an apparatus body having an image forming unit for forming an image on a recording material; a fixing unit having a fixing unit for fixing the image formed by the image forming unit to the recording material, and being detachable from the apparatus body; a first duct attached to the fixing unit so as to face the fixing unit and through which gas for cooling the fixing unit flows; and a second duct attached to the apparatus body so as to be adjacent to the first duct and through which gas for cooling the fixing unit flows, wherein the second duct is provided between the image forming unit and the fixing unit. The invention of claim 6 is an image forming apparatus comprising: an apparatus body having an image forming unit for forming an image on a recording material; a fixing unit having a fixing unit for fixing the image formed by the image forming unit to the recording material and a transport unit for transporting the recording material toward the fixing unit, the fixing unit being detachable from the apparatus body; a first duct attached to the fixing unit so as to face the fixing unit and through which a gas for cooling the fixing unit flows; and a second duct attached to the apparatus body adjacent to the first duct and through which a gas for cooling the fixing unit flows, wherein the second duct is attached to the apparatus body so as to face the transport unit of the fixing unit. The invention of claim 7 is an image forming apparatus comprising: an apparatus body having an image forming unit for forming an image on a recording material and a support for supporting the image forming unit; a fixing unit having a fixing unit for fixing the image formed by the image forming unit to the recording material and being detachable from the apparatus body; a first duct attached to the fixing unit so as to face the fixing unit and through which gas for cooling the fixing unit flows; and a second duct attached to the apparatus body so as to be adjacent to the first duct and through which gas for cooling the fixing unit flows, wherein the second duct is supported by the support of the apparatus body. The invention of claim 8 is an image forming apparatus comprising: an apparatus body having an image forming unit for forming an image on a recording material; a fixing unit having a fixing unit for fixing the image formed by the image forming unit to the recording material and being detachable from the apparatus body; a first duct attached to the fixing unit so as to face the fixing unit and through which gas for cooling the fixing unit flows; and a second duct attached to the apparatus body so as to be adjacent to the first duct and through which gas for cooling the fixing unit flows, wherein the first duct and the second duct merge at the apparatus body. The invention of claim 9 is an image forming apparatus according to claim 8, characterized in that the first duct and the second duct merge outside the transport area in which the recording material can be transported to the fixing section. The invention of claim 10 is an image forming apparatus according to any one of claims 1, 2, 6 to 8, characterized in that the first duct draws in air from a position closer to the outside of the apparatus body compared to the second duct. [Effects of the Invention]

[0006] Claim 1 、2、5~8 According to this invention, compared to the case in which a fixing unit that can be attached to the main body of the device is provided with multiple ducts, it is possible to suppress the decrease in visibility when the fixing unit is pulled out from the main body of the device while maintaining the cooling efficiency of the fixing unit. Claim 3 According to this invention, compared to the case where the intake port of the second duct is not facing downward in the direction of gravity, the gas that has become hot due to the heat generated in the fixing part can more easily enter the intake port of the second duct. Claim 4 According to this invention, compared to a case without a shielding portion, it becomes easier to cool the area around the fixing portion while suppressing a decrease in the fixing temperature. Claim 9 According to this invention, compared to the case where the first duct and the second duct merge inside the conveying area, unevenness in the fixing temperature in the conveying area can be suppressed. According to the invention of claim 10, the cooling efficiency of the fixing section by the first duct is improved. [Brief explanation of the drawing]

[0007] [Figure 1] This is a schematic diagram showing an image forming apparatus to which this embodiment is applied. [Figure 2] Figure 1 is an enlarged view of section II in the image forming apparatus shown. [Figure 3] This diagram illustrates the configuration of the blower mechanism, and is an enlarged view of the area surrounding the blower mechanism in Figure 2. [Figure 4] This is a cross-sectional view taken at section IV-IV in Figure 2. [Figure 5] This is a view of the first and second ducts of the blower mechanism from the V direction in Figure 3. [Figure 6] This is a perspective view of the second duct, seen from the front in the depth direction, the downstream in the transport direction, and from above in the direction of gravity. [Figure 7] This is a view of the second duct shown in Figure 6, taken from direction VII. [Figure 8] This is a perspective view showing the state in which the detachable unit has been pulled out from the main body of the image forming apparatus to which this embodiment is applied. [Figure 9] This is a view of the device body shown in Figure 8 from below. [Modes for carrying out the invention]

[0008] Embodiments of the present invention will be described below with reference to the attached drawings. Figure 1 is a schematic diagram showing an image forming apparatus 1 to which this embodiment is applied. Figure 2 is an enlarged view of section II in the image forming apparatus 1 shown in Figure 1. The image forming apparatus 1 shown in the figure is an intermediate transfer type image forming apparatus, generally known as a tandem type. This image forming apparatus 1 is equipped with multiple image forming units 10Y, 10M, 10C, and 10K in which toner images of each color component are formed by electrophotography. The image forming units 10Y, 10M, 10C, and 10K each form images of yellow (Y), magenta (M), cyan (C), and black (K), respectively (hereinafter, these colors may be referred to as normal colors).

[0009] Further, the image forming apparatus 1 is provided with a primary transfer unit 10 that sequentially performs primary transfer of the toner images of respective color components formed by each of the image forming units 10Y, 10M, 10C, and 10K onto the intermediate transfer belt 15. Furthermore, the image forming apparatus 1 is provided with a secondary transfer unit 20 as an example of an image forming unit that collectively performs secondary transfer of the superimposed toner image transferred onto the intermediate transfer belt 15 onto a sheet P as an example of a recording material.

[0010] Each of the image forming units 10Y, 10M, 10C, and 10K is provided with the following electrophotographic devices. First, a charger 12 that charges the photosensitive drum 11 is provided around the photosensitive drum 11 that rotates in the clockwise direction in FIG. 1. Also, a laser exposure device 13 that writes an electrostatic latent image on the photosensitive drum 11 is provided. Note that the exposure beam by the laser exposure device 13 is indicated by reference numeral Bm in FIG. 1. In the following description, the photosensitive drums 11 provided in each of the image forming units 10Y, 10M, 10C, and 10K may be denoted as photosensitive drums 11Y, 11M, 11C, and 11K.

[0011] Furthermore, a developing device 14 that houses a developer containing a carrier and toner and visualizes the electrostatic latent image on the photosensitive drum 11 with the toner is provided. Also, a primary transfer roll 16 that transfers the toner images of respective colors formed on the photosensitive drum 11 to the intermediate transfer belt 15 by the primary transfer unit 10 is provided. Also, a drum cleaner 17 that removes the toner remaining on the photosensitive drum 11 is provided. The drum cleaner 17 is composed of, for example, a cleaning blade that contacts the surface of the photosensitive drum 11 and scrapes off the toner remaining on the surface of the photosensitive drum 11. In the following description, the drum cleaners 17 provided in each of the image forming units 10Y, 10M, 10C, and 10K may be denoted as drum cleaners 17Y, 17M, 17C, and 17K.

[0012] The intermediate transfer belt 15 moves in a predetermined counterclockwise direction in Figure 1 at a predetermined speed by a drive roll 34 driven by a motor (not shown). The primary transfer section 10 includes primary transfer rolls 16 that are positioned opposite each other on either side of the intermediate transfer belt 15. Then, the toner images on each photoreceptor drum 11 are sequentially attracted to the intermediate transfer belt 15 by electrostatic attraction, and a superimposed toner image is formed on the intermediate transfer belt 15.

[0013] The secondary transfer unit 20 includes a secondary transfer roll 21, a belt member 22, and a support roll 23, which are positioned on the outer circumference (toner image holding surface side) of the intermediate transfer belt 15. The secondary transfer unit 20 also includes a backup roll 25, which are positioned on the inner circumference of the intermediate transfer belt 15. In the secondary transfer unit 20, the belt member 22 is wound around and supported on the outer circumference of the secondary transfer roll 21 and the support roll 23. In the secondary transfer unit 20, the outer circumference of the intermediate transfer belt 15 and the outer circumference of the belt member 22 are in contact. Furthermore, in the secondary transfer unit 20, the secondary transfer roll 21 is positioned to press against the backup roll 25, sandwiching the belt member 22 and the intermediate transfer belt 15. The secondary transfer roll 21 is then grounded, and a secondary transfer bias is formed between the secondary transfer roll 21 and the backup roll 25, and the toner image formed on the intermediate transfer belt 15 is secondary transferred onto the paper P conveyed to the secondary transfer unit 20.

[0014] Furthermore, the image forming apparatus 1 is provided with a fixing device 60, which is an example of a fixing unit for fixing the secondary transferred toner image onto the paper P. The fixing device 60 comprises a fixing belt module 61 and a pressure roll 62 that is pressed against the fixing belt module 61. In this fixing device 60, the paper P is pressurized and heated at the position where the fixing belt module 61 and the pressure roll 62 come into contact (fixing nip), thereby fixing the toner image to the paper P.

[0015] The anchoring belt module 61 comprises an endless anchoring belt 610 and support rolls 611 and 612 that are rotatably mounted and support the anchoring belt 610 from the inside. The support roll 611 receives a driving force from a drive source (not shown) and rotates clockwise in the figure. As the support roll 611 rotates, the anchoring belt 610 receives a driving force from the support roll 611 and moves in a clockwise direction in the figure. Furthermore, the fixing belt module 61 is equipped with a load-receiving member 615 that receives the load from the pressure roll 62 at a position opposite the pressure roll 62, with the fixing belt 610 in between. In the fixing device 60 of this embodiment, the paper P is sandwiched from both sides by the pressure roll 62 and the load-receiving member 615, and pressure is applied to the paper P. Furthermore, the anchoring belt module 61 is provided with heaters (not shown) inside the support rolls 611 and 612 and the load-receiving member 615 to heat them.

[0016] Furthermore, the image forming apparatus 1 is equipped with a transport unit 50 that transports the paper P, on which the toner image has been secondarily transferred in the secondary transfer unit 20, toward the fuser unit 60. The conveying unit 50 includes an endless conveying belt 51 and support rolls 52 and 53 that are rotatably mounted and support the conveying belt 51 from the inside. The support rolls 52 receive driving force from a drive source (not shown) and rotate clockwise in the figure. As the support rolls 52 rotate, the conveying belt 51 receives driving force from the support rolls 52 and moves in a clockwise direction in the figure.

[0017] Furthermore, the image forming apparatus 1 is equipped with a cleaning device 70 for cleaning the surface of the intermediate transfer belt 15. Furthermore, the image forming apparatus 1 is equipped with a recovery device (not shown) that recovers waste toner removed from the photoreceptor drum 11 by the drum cleaners 17Y, 17M, 17C, and 17K of each image forming unit 10Y, 10M, 10C, and 10K, and waste toner removed from the intermediate transfer belt 15 by the cleaning device 70.

[0018] Furthermore, the image forming apparatus 1 is provided with a blower mechanism 100 through which heat discharged from the fixing device 60 and gas for cooling the paper P heated by the fixing device 60 circulate. The blower mechanism 100 in this embodiment includes a first duct 110 and a second duct 120 adjacent to each other in the direction of transport of the paper P in the fixing device 60. The blower mechanism 100 also includes an exhaust section 130 (see Figure 4, described later) that exhausts the gas that has passed through the first duct 110 and the second duct 120 to the outside of the image forming apparatus 1, and a fan 135 (see Figure 4, described later) provided in the exhaust section 130 that generates a gas flow in the first duct 110 and the second duct 120. In addition, the blower mechanism 100 includes a shielding section 140 (see Figure 3, described later) that shields the space between the fixing device 60 and the secondary transfer section 20. The configuration of the blower mechanism 100 will be described in detail later. In the following description, the paper transport direction P in the fuser 60 may be simply referred to as the paper transport direction P or the transport direction.

[0019] Furthermore, the image forming apparatus 1 is provided with an exhaust mechanism 200 that is positioned adjacent to the fixing device 60 on the downstream side in the paper transport direction, and which draws in air from around the fixing device 60 and discharges it outside the image forming apparatus 1.

[0020] Furthermore, the image forming apparatus 1 is provided with a pair of rotatable transport rolls 42 and 43, which transport the paper P discharged from the fixing device 60 further downstream, and a guide section 40 which guides the paper P being transported by the transport roll pair 41. Furthermore, the image forming apparatus 1 is provided with a paper discharge unit 35 that discharges the paper P that has passed through the guide unit 40 to the outside of the image forming apparatus 1.

[0021] Furthermore, the image forming apparatus 1 is provided with a paper transport path R1 that transports paper from the paper storage sections 31, 32, and 33 through the secondary transfer section 20, transport section 50, fixing device 60, transport roll pair 41, and guide section 40 toward the paper discharge section 35. In addition, the image forming apparatus 1 is provided with a paper reversal path R2 that reverses the front and back sides of the paper P after the image has been formed and passed through the transport roll pair 41, and transports this paper toward the secondary transfer section 20 again.

[0022] In the image forming apparatus 1 of this embodiment, the secondary transfer roll 21, belt member 22, and support roll 23 of the secondary transfer section 20, the transport section 50, the fixing device 60, and the first duct 110 and shielding section 140 of the blower mechanism 100 are integrally configured as a detachable unit 1X (see Figure 8, described later). The detachable unit 1X can be attached to and detached from the main body 1Y of the image forming apparatus 1. In addition, the detachable unit 1X is movably mounted on the main body 1Y of the image forming apparatus 1 by guide rails (not shown) or the like, and can be pulled out of the image forming apparatus 1. In this example, the detachable unit 1X is movably mounted in the depth direction of the image forming apparatus 1 and is configured to be pullable out to the front side of the image forming apparatus 1 (the front side in Figure 2).

[0023] In the image forming apparatus 1 of this embodiment, the detachable unit 1X is pulled out from the main body 1Y of the image forming apparatus 1 when a jam occurs, for example, in the transport unit 50 or the fixing unit 60, or when the image forming apparatus 1 is being maintained. In this embodiment, the detachable unit 1X is an example of a fixing unit. The process of removing the detachable unit 1X from the main body 1Y of the image forming apparatus 1 will be explained in more detail later.

[0024] Furthermore, each of the components of the image forming apparatus 1 described above is housed inside the housing 1Z of the apparatus body 1Y. In the image forming apparatus 1 of this embodiment, the image forming units 10Y, 10M, 10C, 10K, the intermediate transfer belt 15, the backup roll 25 of the secondary transfer section 20, and the second duct 120 of the blower mechanism 100 are all supported by a common support of the housing 1Z. This improves the positional accuracy of the second duct 120 relative to the intermediate transfer belt 15 and the backup roll 25 of the secondary transfer section 20.

[0025] The basic image forming process of the image forming apparatus 1 will be described below. In the image forming apparatus 1, image data is output from an image reading device (not shown). This image data is then processed by an image processing device (not shown), converted into four-color color gradation data (Y, M, C, K), and output to the laser exposure unit 13.

[0026] In the laser exposure unit 13, according to the input colorant gradation data, an exposure beam Bm emitted from, for example, a semiconductor laser is irradiated onto each of the photoreceptor drums 11 of the image forming units 10Y, 10M, 10C, and 10K. After the surface of each photoreceptor drum 11 is charged by the charger 12, the surface is scanned and exposed by the laser exposure unit 13 to form an electrostatic latent image. Then, after a toner image is formed on the photoreceptor drum 11 by the developing unit 14, this toner image is transferred onto the intermediate transfer belt 15 in the primary transfer unit 10 where each photoreceptor drum 11 and the intermediate transfer belt 15 are in contact.

[0027] After the toner image is first transferred to the surface of the intermediate transfer belt 15, the toner image is transported to the secondary transfer section 20 by the movement of the intermediate transfer belt 15. In the secondary transfer section 20, the secondary transfer roll 21 is pressed against the backup roll 25 via the belt member 22 and the intermediate transfer belt 15. At this time, the paper P transported from the paper storage sections 31, 32, and 33 by the transport roll 36, etc., is sandwiched between the intermediate transfer belt 15 and the belt member 22.

[0028] Then, the unfixed toner image held on the intermediate transfer belt 15 is electrostatically transferred in one go onto the paper P in the secondary transfer unit 20. After that, the paper P on which the toner image has been electrostatically transferred is peeled off the intermediate transfer belt 15 and transported to the transport unit 50 located downstream of the secondary transfer unit 20 in the paper transport direction. The paper P transported to the transport unit 50 is then transported to the fixing device 60 by the transport belt 51. The toner image on the paper P, which has been transported to the fuser 60, is subjected to heat and pressure by the fuser 60 and fixed onto the paper P. The paper P on which the fixed image has been formed is then transported by the transport roll pair 41, passes through the guide section 40, and is discharged from the paper discharge section 35 to the outside of the image forming apparatus 1. On the other hand, toner adhering to the photoreceptor drum 11 after primary transfer is removed by the drum cleaner 17, and toner adhering to the intermediate transfer belt 15 after secondary transfer is removed by the cleaning device 70. The toner (waste toner) removed by the drum cleaner 17 and the cleaning device 70 is collected in a recovery unit (not shown). In this way, the image forming process in the image forming apparatus 1 is repeatedly executed for the number of prints required.

[0029] Next, the blower mechanism 100 of this embodiment will be described. Figure 3 is a diagram illustrating the configuration of the blower mechanism 100, and is an enlarged view of the area around the blower mechanism 100 in Figure 2. Figure 4 is a cross-sectional view taken at section IV-IV in Figure 2. Figure 5 is a view of the first duct 110 and the second duct 120 of the blower mechanism 100 as seen from direction V in Figure 3. As described above, the blower mechanism 100 includes a first duct 110 and a second duct 120 arranged adjacent to each other in the direction of transport of the paper P, an exhaust section 130 for discharging the gas that has passed through the first duct 110 and the second duct 120, and a shielding section 140 for shielding the space between the fixing device 60 and the secondary transfer section 20.

[0030] The first duct 110 is an example of a first duct through which gas for cooling the fixing device 60 flows. As described above, the first duct 110 is attached to the detachable unit 1X of the image forming apparatus 1. In this example, the first duct 110 is provided integrally with the fixing device 60, which is also attached to the detachable unit 1X. When the detachable unit 1X is not pulled out from the main body 1Y of the image forming apparatus 1 (when the detachable unit 1X is mounted on the main body 1Y), the first duct 110 is connected to the second duct 120 and the exhaust unit 130.

[0031] The first duct 110 is located between the intermediate transfer belt 15 and the fixing device 60. Furthermore, the first duct 110 is positioned opposite the portion of the fixing belt 610 of the fixing device 60 that is supported between the support roll 611 and the support roll 612, with a gap in between. In this embodiment, when the first duct 110 and the fixing device 60 are viewed from above, the length of the first duct 110 along the direction of transport of the paper P is longer than the fixing belt module 61 of the fixing device 60. In this embodiment, the first duct 110 also functions as a covering portion that covers the top of the fixing device 60.

[0032] Furthermore, the first duct 110 has a flattened shape that extends along the direction of transport of the paper P and the depth direction of the image forming apparatus 1. Inside the first duct 110, a space S1 through which gas flows is formed.

[0033] The first duct 110 has a first surface 110A and a second surface 110B that are opposite each other in the vertical direction across the space S1. In this example, the first surface 110A is provided along the portion of the fixing belt 610 of the fixing device 60 that is supported between the support roll 611 and the support roll 612. The second surface 110B is provided along the intermediate transfer belt 15.

[0034] Furthermore, the first duct 110 has an intake port 111 that opens toward the front of the image forming apparatus 1 and draws gas into the space S1, and an exhaust port 112 that opens toward the rear of the image forming apparatus 1 and exhausts the gas drawn in through the intake port 111 from the space S1 to the exhaust section 130.

[0035] The second duct 120 is an example of a second duct through which gas for cooling the fixing device 60 flows. As described above, the second duct 120 is attached to the main body 1Y of the image forming apparatus 1. The second duct 120 is connected to the first duct 110 when the detachable unit 1X is not pulled out from the main body 1Y of the image forming apparatus 1. In addition, when the detachable unit 1X is not pulled out from the main body 1Y of the image forming apparatus 1, the second duct 120 merges with the first duct 110 at the main body 1Y.

[0036] The second duct 120 is positioned adjacent to the first duct 110 in the direction of transport of the paper P being transported by the fixing device 60. More specifically, the second duct 120 is positioned adjacent to the first duct 110 on the upstream side in the direction of transport of the paper P. Furthermore, the second duct 120 is provided between the secondary transfer unit 20 (see Figure 2) and the fixing device 60 in the direction of transporting the paper P. Furthermore, the second duct 120 is provided along the intermediate transfer belt 15. Furthermore, the second duct 120 is located above the conveying section 50 and faces the conveying belt 51 of the conveying section 50 through a gap. Furthermore, the second duct 120 is positioned above the anchoring device 60 in the direction of gravity.

[0037] The second duct 120 has a flattened shape overall in the direction of transporting the paper P and in the depth direction of the image forming apparatus 1. A space S2 through which gas flows is formed inside the second duct 120. Figures 6 and 7 illustrate the configuration of the second duct 120. Figure 6 is a perspective view of the second duct 120 from the front in the depth direction, the downstream in the transport direction, and from above in the direction of gravity. Figure 7 is a view of the second duct 120 shown in Figure 6 from direction VII (downward in the direction of gravity).

[0038] The second duct 120 of this embodiment has a long section 120A that extends along the depth direction of the image forming apparatus 1, and an extended section 120B that extends from the far end of the long section 120A toward the downstream side in the direction of transporting the paper P. In the second duct 120 of this embodiment, the length of the elongated section 120A along the depth direction is longer than the paper transport area in the fixing device 60 where the paper P can be transported. In addition, in the second duct 120, the extended section 120B is located further back in the depth direction than the paper transport area. Note that the paper transport area is an example of a transport area in which recording material can be transported.

[0039] Furthermore, the second duct 120 has a first surface 120C and a second surface 120D that face each other vertically across the space S2. In this example, the first surface 120C faces the conveyor belt 51 of the conveying section 50 through a gap. The second surface 120D is provided along the intermediate transfer belt 15.

[0040] Furthermore, the second duct 120 is provided on the first surface 120C of the elongated section 120A and has a plurality (three in this example) intake ports 121 into which gas is drawn towards the space S2. In this example, each intake port 121 is arranged in a line with a gap between them in the depth direction at the upstream end in the transport direction of the first surface 120C. Furthermore, each of the air intake ports 121 opens downward. In other words, each of the air intake ports 121 faces downward in the direction of gravity. In this embodiment, "the air intake ports 121 face downward in the direction of gravity" means that when the second duct 120 is viewed from below in the direction of gravity, the space S2 can be seen through the air intake ports 121.

[0041] In this example, the length of the region in the elongated section 120A where the air intake 121 is not formed is longer than the length of the region in the elongated section 120A where the air intake 121 is formed, both in the depth direction. This makes it easier for the gas that enters the space S2 through the air intake 121 to flow towards the back in the depth direction.

[0042] Furthermore, the second duct 120 is provided at the rear end in the depth direction of the extension section 120B, opens toward the rear in the depth direction, and has an exhaust port 122 that exhausts the gas drawn in through the intake port 121 from the space S2 to the exhaust section 130. In this embodiment, the second duct 120 and the first duct 110 merge at an exhaust section 130 located further back in the depth direction than the paper transport area, via exhaust ports 122 or 112, respectively.

[0043] Furthermore, the second duct 120 is provided on the second surface 120D of the elongated portion 120A and has a plurality (two in this example) mounting portions 123 for attaching the second duct 120 to the housing 1Z. In this embodiment, the second duct 120 is supported by the device body 1Y by being attached to the housing 1Z via the mounting portions 123. The second duct 120 is attached to the housing 1Z, for example, by screwing it in via the mounting portions 123.

[0044] The exhaust section 130 includes an exhaust path 131 through which the gas discharged from the first duct 110 and the second duct 120 flows. The exhaust path 131 is connected to an exhaust port 112 located at the far end of the first duct 110 and an exhaust port 122 located at the far end of the second duct 120, and extends downward in the direction of gravity. Furthermore, the exhaust section 130 is provided at the end of the exhaust path 131 and includes an exhaust port 132 that discharges the gas that has passed through the exhaust path 131 to the outside of the image forming apparatus 1. Furthermore, the exhaust section 130 is located inside the exhaust path 131 and includes a fan 135 that rotates due to a drive source (not shown) and generates a gas flow in the first duct 110 and the second duct 120.

[0045] The shielding portion 140 shields the space between the fixing device 60 and the secondary transfer portion 20. The shielding portion 140 is formed by a wall surface extending downward in the direction of weight from the upstream end in the transport direction on the first surface 110A of the first duct 110. In this embodiment, the blower mechanism 100 is equipped with a shielding section 140, which suppresses the transfer of heat generated in the fixing device 60 to the secondary transfer section 20, thereby suppressing the temperature rise of the secondary transfer section 20.

[0046] Next, the operation of the blower mechanism 100 will be explained. When the fixing device 60 and the like are cooled using the blower mechanism 100, the fan 135 of the exhaust section 130 is driven and rotated by a drive source (not shown). As a result, gas flows through the space S1 of the first duct 110 and the space S2 of the second duct 120, cooling the fixing device 60 and the area around it.

[0047] To explain in more detail, in the first duct 110, as shown in Figure 4, gas enters the main body 1Y of the image forming apparatus 1 from the outside of the apparatus body 1Y through gaps formed in the housing 1Z, and moves from bottom to top along the inner surface of the housing 1Z, and is drawn into space S1 through the intake port 111. The gas that has entered space S1 then circulates within the first duct 110 from the front to the back in the depth direction. At this time, heat generated from the fixing device 60 is transferred to the gas circulating within the first duct 110, and the fixing device 60 is cooled. The gas that has flowed through the first duct 110 then enters the exhaust path 131 of the exhaust section 130 via the exhaust port 112. After that, the gas that has entered the exhaust path 131 is discharged to the image forming apparatus 1 via the exhaust port 132.

[0048] Furthermore, in the second duct 120, as shown in Figures 3 and 5, gas is drawn into the space S2 of the long section 120A from the space located upstream of the conveying direction of the fixing device 60 through the respective intake ports 121. The gas that enters the space S2 then flows through the long section 120A of the second duct 120 from the front to the back in the depth direction. The gas that reaches the back end of the long section 120A of the second duct 120 then flows through the extension section 120B from the front to the back in the depth direction and enters the exhaust path 131 of the exhaust section 130 through the exhaust port 122. After that, the gas that enters the exhaust path 131, together with the gas that has flowed through the first duct 110, is discharged to the image forming apparatus 1 side through the exhaust port 132. In this way, the high-temperature gas present around the fixing device 60 is discharged to the outside of the image forming apparatus 1 via the second duct 120, thereby cooling the fixing device 60 and the area around it.

[0049] As described above, the blower mechanism 100 of this embodiment includes a first duct 110 and a second duct 120 through which gas for cooling the fixing device 60 flows. As a result, compared to, for example, the case in which the blower mechanism 100 is equipped with only one of the first duct 110 or the second duct 120, the amount of gas flowing to cool the fixing device 60 is increased, and the cooling efficiency of the fixing device 60 by the blower mechanism 100 is improved.

[0050] Here, the intake port 121 of the second duct 120 draws in air from between the fuser 60 and the secondary transfer section 20 (see Figure 2). By adopting this configuration, the gas that has become hot due to the heat from the fuser 60 is more easily discharged to the outside of the image forming apparatus 1 by the second duct 120, improving the cooling efficiency of the fuser 60 by the blower mechanism 100. In addition, the secondary transfer section 20 is prevented from becoming hot due to the heat from the fuser 60, and the occurrence of transfer defects and other problems caused by toner melting in the secondary transfer section 20 is suppressed.

[0051] Furthermore, the intake port 121 of the second duct 120 draws in air from the secondary transfer section 20 side rather than the shielding section 140. By adopting this configuration, for example, the decrease in the temperature of the fixing belt 610 heading toward the fixing nip section is suppressed compared to cases where the intake port 121 draws in air from the fixing device 60 side rather than the shielding section 140, or where the blower mechanism 100 does not have a shielding section 140. As a result, the fixing device 60 and the area around the fixing device 60 can be cooled while suppressing the decrease and fluctuation of the fixing temperature due to the intake air from the second duct 120.

[0052] Furthermore, the intake port 121 of the second duct 120 faces downward in the direction of gravity. By adopting this configuration, the heat from the fixing device 60 causes natural convection to flow from downward to upward in the direction of gravity around the fixing device 60, making it easier for high-temperature gas to enter the intake port 121. As a result, compared to the case where the intake port 121 does not face downward in the direction of gravity, the gas that has become hot due to the heat from the fixing device 60 is more easily discharged to the outside of the image forming apparatus 1 by the second duct 120, and the cooling efficiency of the fixing device 60 by the blower mechanism 100 is improved.

[0053] Furthermore, in the blower mechanism 100 of this embodiment, the first duct 110 draws in gas that has entered the device body 1Y from the outside of the device body 1Y through gaps formed in the housing 1Z, etc., from the intake port 111 formed at the front end of the first duct 110. In addition, the first duct 110 draws in air from a position closer to the outside of the device body 1Y compared to the second duct 120. By adopting this configuration, the first duct 110 can more easily take in low-temperature gas present outside the device body 1Y into the space S1. As described above, the first duct 110 is provided opposite the fixing device 60, which tends to become hot. In this embodiment, the fixing device 60 can be cooled more effectively by making it easier to draw in the space S1 of the first duct 110 from the cooler gas present outside the main body 1Y.

[0054] Furthermore, in the blower mechanism 100 of this embodiment, the first duct 110 and the second duct 120 merge at an exhaust section 130 provided in the main body 1Y of the device. In addition, in the blower mechanism 100, a common fan 135 rotates to circulate gas through the first duct 110 and the second duct 120. Furthermore, in the blower mechanism 100, the gas that has circulated through the first duct 110 and the gas that has circulated through the second duct 120 are discharged to the outside of the image forming apparatus 1 via a common exhaust path 131 and exhaust port 132. By adopting such a configuration, the structure of the blower mechanism 100 can be simplified compared to, for example, a case where fans for circulating gas and exhaust paths and exhaust ports for discharging gas are individually provided in the first duct 110 and the second duct 120.

[0055] Furthermore, in the blower mechanism 100 of this embodiment, the first duct 110 and the second duct 120 merge behind the paper transport area of ​​the fuser device 60, in other words, outside the paper transport area. By adopting this configuration, for example, compared to the case where the first duct 110 and the second duct 120 merge inside the paper transport area, fluctuations in the flow rate and temperature of the gas flowing through the first duct 110 and the second duct 120 inside the paper transport area are suppressed. As a result, temperature unevenness in the fuser device 60 is less likely to occur in the paper transport area, and fixing failures by the fuser device 60 are suppressed.

[0056] Next, we will describe how the detachable unit 1X is pulled out from the main body 1Y of the image forming apparatus 1. Figure 8 is a perspective view showing the state in which the detachable unit 1X has been pulled out from the main body 1Y of the image forming apparatus 1 to which this embodiment is applied. Figure 9 is a view of the main body 1Y of the apparatus shown in Figure 8 from below. In the image forming apparatus 1 of this embodiment, the detachable unit 1X is pulled out from the main body 1Y of the image forming apparatus 1 towards the front when a jam occurs, for example, when paper P gets stuck in the transport unit 50 or the fixing device 60, or when the image forming apparatus 1 is being maintained. When the detachable unit 1X is pulled out from the main body 1Y, each component attached to the detachable unit 1X is pulled out to the outside of the image forming apparatus 1.

[0057] Now, consider the case where, in the image forming apparatus 1, a first duct 110 and a second duct 120 are provided to improve the cooling efficiency of the fixing device 60, etc., and both the first duct 110 and the second duct 120 are attached to the detachable unit 1X. In this case, when the detachable unit 1X is pulled out from the main body 1Y of the apparatus, it may be difficult for the user to see the transport unit 50 and the fixing device 60 provided on the detachable unit 1X because they are covered by the first duct 110 and the second duct 120. In this case, for example, if a jam occurs in the transport unit 50 or the fixing device 60, etc., the paper P may get stuck, or the user's workability during maintenance of the image forming apparatus 1 may be reduced.

[0058] In contrast, in this embodiment, the blower mechanism 100 has the first duct 110 attached to the detachable unit 1X, while the second duct 120 is attached to the main body 1Y of the device. Then, when the detachable unit 1X is pulled out from the main body 1Y toward the front, the first duct 110 is pulled out from the main body 1Y toward the outside of the image forming apparatus 1 along with the detachable unit 1X. On the other hand, the second duct 120 is not pulled out toward the outside of the image forming apparatus 1, but remains inside the main body 1Y.

[0059] As a result, compared to the case where the second duct 120 is attached to the detachable unit 1X, for example, when the detachable unit 1X is pulled out, the transport section 50 and fixing device 60 provided on the detachable unit 1X are more easily exposed to the outside. In this case, for example, if a jam occurs in the transport section 50 or fixing device 60, etc., or when performing maintenance on the image forming apparatus 1, the workability for the user is improved.

[0060] In particular, in this embodiment, when the detachable unit 1X is not pulled out from the main body 1Y, the second duct 120 is attached to the main body 1Y so as to face the transport section 50. By adopting this configuration, when the detachable unit 1X is pulled out, the second duct 120 remains inside the main body 1Y without being pulled out, making it easier to expose the transport section 50 to the outside. This improves the visibility of the transport section 50 to the user, making it easier to resolve jams, for example, if a paper jam occurs in the transport section 50.

[0061] Incidentally, if the blower mechanism 100 includes a first duct 110 and a second duct 120, from the viewpoint of suppressing the decrease in visibility of the transport section 50 and the fixing device 60 when the detachable unit 1X is pulled out from the device body 1Y, it is conceivable to attach both the first duct 110 and the second duct 120 to the device body 1Y. However, if such a configuration is adopted, when the detachable unit 1X is pulled out from the device body 1Y, the high-temperature fixing device 60 is more likely to be exposed to the outside, and there is a risk that the user may directly touch the high-temperature fixing device 60.

[0062] In contrast, in this embodiment, the first duct 110 is attached to the detachable unit 1X so as to face the top of the fixing device 60. When the detachable unit 1X is pulled out, the first duct 110 is pulled out to the outside of the device body 1Y together with the fixing device 60. By adopting this configuration, when the detachable unit 1X is pulled out, the top of the high-temperature fixing device 60 is prevented from being exposed to the outside, and the user is prevented from directly touching the high-temperature fixing device 60.

[0063] In this embodiment, the first duct 110 attached to the detachable unit 1X and the second duct 120 attached to the main body 1Y of the device are arranged adjacent to each other in the direction of transport of the paper P, but the embodiment is not limited to this configuration. The first duct 110 and the second duct 120 may be arranged adjacent to each other in the depth direction of the image forming apparatus 1. For example, the first duct 110 attached to the detachable unit 1X may be positioned in front of the second duct 120 attached to the main body 1Y of the device in the depth direction.

[0064] While embodiments of the present invention have been described above, the configurations described above are not limited to the embodiments and their modifications, and can be modified without departing from the spirit of the invention. In other words, it is understood that a variety of changes in form and details are possible without departing from the spirit and scope of the claims. For example, some of the components described above may be omitted, or other functions may be added to each component described above. [Explanation of symbols]

[0065] 1…Image forming apparatus, 1X…Detachable unit, 1Y…Apparatus body, 50…Conveyor unit, 51…Conveyor belt, 60…Fixing device, 61…Fixing belt module, 62…Pressure roll, 100…Blowering mechanism, 110…First duct, 111…Intake port, 112…Exhaust port, 120…Second duct, 121…Intake port, 122…Exhaust port, 130…Exhaust unit, 131…Exhaust path, 132…Exhaust port, 135…Fan

Claims

1. A device body having an image forming unit that forms an image on a recording material, A fixing unit having a fixing unit for fixing the image formed by the image forming unit onto a recording material, and which is detachable from the main body of the device, A first duct is attached to the fixing unit so as to face the fixing portion, and through which gas for cooling the fixing portion flows, A second duct is attached to the main body of the apparatus adjacent to the first duct, and through which gas for cooling the fixing part flows. Equipped with, An image forming apparatus in which the space through which gas flows in the first duct and the space through which gas flows in the second duct are formed by independent and distinct surfaces.

2. A device body having an image forming unit that forms an image on a recording material, A fixing unit having a fixing unit for fixing the image formed by the image forming unit onto a recording material, and which is detachable from the main body of the device, A first duct is attached to the fixing unit so as to face the fixing portion, and through which gas for cooling the fixing portion flows, A second duct is attached to the main body of the apparatus adjacent to the first duct, and through which gas for cooling the fixing part flows. Equipped with, The second duct is attached to the main body of the apparatus so as to be adjacent to the first duct on the upstream side in the transport direction of the recording material being transported to the fixing unit, and the image forming apparatus has an air intake port for drawing in air from between the fixing unit and the image forming unit.

3. The image forming apparatus according to claim 2, characterized in that the second duct is provided above the fixing portion in the direction of gravity, and the air intake port faces downward in the direction of gravity.

4. The fixing unit further includes a shielding portion that shields the space between the fixing portion and the image forming portion. The image forming apparatus according to claim 2 or 3, characterized in that the intake port of the second duct draws in air from the image forming section side rather than the shielding section.

5. A device body having an image forming unit that forms an image on a recording material, A fixing unit having a fixing unit for fixing the image formed by the image forming unit onto a recording material, and which is detachable from the main body of the device, A first duct is attached to the fixing unit so as to face the fixing portion, and through which gas for cooling the fixing portion flows, A second duct is attached to the main body of the apparatus adjacent to the first duct, and through which gas for cooling the fixing part flows. Equipped with, The second duct is an image forming apparatus provided between the image forming unit and the fixing unit.

6. A device body having an image forming unit that forms an image on a recording material, A fixing unit having a fixing unit for fixing the image formed by the image forming unit onto a recording material, and a transport unit for transporting the recording material toward the fixing unit, and which is detachable from the main body of the apparatus, A first duct is attached to the fixing unit so as to face the fixing portion, and through which gas for cooling the fixing portion flows, A second duct is attached to the main body of the apparatus adjacent to the first duct, and through which gas for cooling the fixing part flows. Equipped with, The second duct is attached to the main body of the image forming apparatus so as to face the transport section of the fixing unit.

7. The apparatus body includes an image forming unit that forms an image on a recording material and a support that supports the image forming unit, A fixing unit having a fixing unit for fixing the image formed by the image forming unit onto a recording material, and which is detachable from the main body of the device, A first duct is attached to the fixing unit so as to face the fixing portion, and through which gas for cooling the fixing portion flows, A second duct is attached to the main body of the apparatus adjacent to the first duct, and through which gas for cooling the fixing part flows. Equipped with, The second duct is an image forming apparatus supported by the support of the main body of the apparatus.

8. A device body having an image forming unit that forms an image on a recording material, A fixing unit having a fixing unit for fixing the image formed by the image forming unit onto a recording material, and which is detachable from the main body of the device, A first duct is attached to the fixing unit so as to face the fixing portion, and through which gas for cooling the fixing portion flows, A second duct is attached to the main body of the apparatus adjacent to the first duct, and through which gas for cooling the fixing part flows. Equipped with, The first duct and the second duct are joined at the main body of the image forming apparatus.

9. The image forming apparatus according to claim 8, characterized in that the first duct and the second duct merge outside the transport area in which the recording material can be transported to the fixing section.

10. The image forming apparatus according to any one of claims 1, 2, 6 to 8, characterized in that the first duct draws in air from a position closer to the outside of the apparatus body compared to the second duct.

Images