JP2016071281A - Image forming apparatus - Google Patents

Abstract

PROBLEM TO BE SOLVED: To make it possible to cool a portion that is difficult to cool by taking in the air from the outside of an image forming unit.SOLUTION: An air-blowing fan 60 sucks the air around a print circuit board 50 that is an area, in an area below a CRU 20, in a low temperature atmosphere compared with the temperature of the CRU 20 in operation, and transmits the air to an air duct 30. The air duct 30 flows and blows the air blown by the air-blowing fan 60 to a portion on a side where driving motors 21 and 22 of the CRU 20. In other words, the air duct 30 flows and blows the air blown by the air-blowing fan 60 to a portion in the vicinity of a frame (metal frame) 40 of the CRU 20 for fixing the CRU 20.SELECTED DRAWING: Figure 5

Description

  The present invention relates to an image forming apparatus.

  In Patent Document 1, the laser scanner unit is cooled by passing an air flow guided from the outside of the apparatus into the apparatus by a fan through the duct, and the process cartridge is also cooled by flowing the air flow into the process cartridge. An image forming apparatus is disclosed.

  In Patent Document 2, the air sucked from the outside of the apparatus by the air intake unit is delivered to the air blowing unit through the ventilation path provided inside the skeleton, and the air duct is provided with an air intake opening facing the air blowing unit. A ventilation path image forming apparatus is disclosed in which the image carrier and the control substrate of the fixing unit are cooled via the image forming apparatus.

  In Patent Document 3, openings are provided on the front surface and the back surface of a casing surrounding an image forming area, and a flow path parallel to the axis of the developing roller is formed by an exhaust fan and an intake fan to reduce flow loss. An image forming apparatus capable of efficient cooling is disclosed.

JP 2004-037685 A Japanese Patent Application Laid-Open No. 2006-078534 JP 2009-053312 A

  In an image forming unit in which a photosensitive drum, a charging device, a developing device, a drum cleaner, and the like are integrated, an image forming process causes a temperature rise due to the influence of heat from the fixing device side or self-heating. Then, when the temperature of the image forming unit becomes too high, there is a possibility that a problem called toner blocking that the toner is fixed inside the image forming unit may occur.

  Therefore, an air intake hole is provided in the image forming apparatus, and air is taken in from the air intake hole to cool the image forming unit.

  However, in order to ventilate the air taken in from the outside of the apparatus to the part to be cooled, a ventilation path for connecting the part to be cooled and the outside of the apparatus is required. Also, due to the recent miniaturization of image forming apparatuses, it may be difficult to provide a ventilation path in the apparatus. For this reason, the image forming unit includes a portion that cannot be cooled using air taken from outside the apparatus due to the structure of the apparatus.

  In particular, on the side where the drive motor is provided in the image forming unit, the drive motor, a metal frame or the like existing between the drive motor and the image forming unit is configured to prevent heat dissipation, and externally. It is difficult to cool using the introduced air.

  An object of the present invention is to provide an image forming apparatus capable of cooling a portion that is difficult to cool by taking in air from the outside of the image forming unit.

According to a first aspect of the present invention, there is provided an image forming unit having an image holding body for holding an image formed by developing a latent image;
A blowing unit for sucking and blowing air in a region having a low temperature atmosphere compared to a temperature during operation of the image forming unit in a region below the image forming unit;
It is an image forming apparatus provided with a ventilation path for allowing the air blown by the blowing means to flow to the image forming unit.

  According to a second aspect of the present invention, in the image forming apparatus according to the first aspect, the air passage causes the air blown from the blower to pass through the portion of the image forming unit on the side where the drive motor is attached. It is.

  According to a third aspect of the present invention, there is provided the first aspect of the present invention, wherein the air passage causes the air blown from the blower to pass through a portion of the image forming unit close to a frame for fixing the image forming unit. This is an image forming apparatus.

  According to a fourth aspect of the present invention, the air blowing means sucks air around a printed wiring board on which an electronic circuit component for controlling an image forming operation is mounted and blows the air to the ventilation path. The image forming apparatus according to claim 1.

  The present invention according to claim 5 is the image forming apparatus according to any one of claims 1 to 4, wherein the blowing means is a blower fan.

  According to the first aspect of the present invention, it is possible to provide an image forming apparatus capable of cooling a portion that is difficult to cool by taking in air from the outside of the image forming unit.

  According to the second aspect of the present invention, there is provided an image forming apparatus capable of cooling a portion to which a drive motor is attached, which is difficult to cool by taking in air from the outside of the image forming unit. Can do.

  According to the third aspect of the present invention, an image forming apparatus capable of cooling a portion close to a frame for fixing the image forming unit, which is difficult to cool by taking in air from the outside of the image forming unit. Can be provided.

  According to the fourth aspect of the present invention, there is provided an image forming apparatus capable of cooling a printed wiring board and cooling a portion that is difficult to cool by taking in air from the outside of the image forming unit. be able to.

  According to the fifth aspect of the present invention, it is possible to provide an image forming apparatus capable of cooling a portion that is difficult to cool by taking in air from the outside of the image forming unit.

1 is an external view of an image forming apparatus 10 according to an embodiment of the present invention as viewed from the front side (front side). 1 is a perspective view of an image forming apparatus 10 according to an embodiment of the present invention when viewed from the rear side (rear side). 1 is an external view of the inside of an image forming apparatus 10 according to an embodiment of the present invention as viewed from the rear side. It is an external view at the time of removing the printed wiring board 50 in FIG. FIG. 5 is an enlarged perspective view in which a part of the drive motors 21 and 22 and the frame 40 are removed from the periphery of the ventilation duct 30 in FIG. 4. It is an external view at the time of seeing the surroundings of the ventilation duct 30 from the rear side. It is an external view only of the ventilation duct 30 and the ventilation fan 60. FIG. FIG. 3 is a diagram showing a positional relationship between the ventilation duct 30, the printed wiring board 50, and the frame 40. It is a figure for demonstrating the other structure provided in order to cool CRU20.

  Next, embodiments of the present invention will be described in detail with reference to the drawings.

  FIG. 1 is an external view of an image forming apparatus 10 according to an embodiment of the present invention as viewed from the front side (front side).

  An image forming apparatus 10 according to an embodiment of the present invention is a so-called multifunction device having a plurality of functions such as a print function, a scan function, a copy function, and a facsimile function.

  2 is a perspective view of the image forming apparatus 10 according to the embodiment of the present invention when viewed from the rear side (rear side).

  Next, FIG. 3 shows an external view when the exterior of the image forming apparatus 10 of the present embodiment is removed and the inside of the apparatus is viewed from the rear side.

  Referring to FIG. 3, the image forming apparatus 10 includes a CRU (Consumer Replaceable Unit) 20 attached to a frame (metal frame) 40, a ventilation duct (air duct) 30, and a printed wiring board 50. Yes.

  The CRU 20 is an image forming unit in which a photosensitive drum, a charger, a developing device, a drum cleaner, and the like, which are image holding members for holding a toner image formed by developing an electrostatic latent image, are integrated. This is a so-called process cartridge unit. The CRU 20 is configured so that the user can replace the CRU 20 when the expiration date is exceeded.

  The charger is a device for charging the photosensitive drum, and the developer is a device for developing the electrostatic latent image formed on the photosensitive drum with toner.

  The CRU 20 is provided with drive motors 21 and 22 for driving a developing unit, a photosensitive drum, and the like.

  As can be seen from FIG. 3, the portion of the CRU 20 to which the drive motors 21 and 22 are attached is supported by the frame 40 on the rear side of the apparatus.

  The ventilation duct (ventilation pipe, ventilation path) 30 is provided to cool the CRU 20, but a specific structure will be described later.

  Next, FIG. 4 shows an external view when the printed wiring board 50 is removed in FIG.

  Referring to FIG. 4, it can be seen that a blower fan 60 is provided below the ventilation duct 30.

  The blower fan 60 is a blower unit that sucks and blows air in a region having a lower temperature atmosphere than the temperature during operation of the CRU 20 in the region below the CRU 20. Specifically, the blower fan 60 sucks air around the printed wiring board 50 on which electronic circuit components for controlling the image forming operation are mounted and blows the air to the ventilation duct 30.

  The ventilation duct 30 functions as a ventilation path for carrying the air blown by the blower fan 60 upward in the vertical direction to ventilate the CRU 20. The ventilation duct 30 blows and blows air that has been blown from the blower fan 60 to a portion of the CRU 20 on which the drive motors 21 and 22 are attached. That is, the ventilation duct 30 blows and blows air that has been blown from the blower fan 60 to a portion of the CRU 20 that is close to the frame (metal frame) 40 for fixing the CRU 20.

  The ventilation duct 30 has a structure that extends vertically downward from the position of the CRU 20 in order to take in air for cooling the CRU 20 from below the image forming apparatus 10.

  Next, FIG. 5 shows an enlarged perspective view in which a part of the drive motors 21 and 22 and the frame 40 are removed from the periphery of the ventilation duct 30 in FIG.

  Referring to FIG. 5, the air blown from the blower fan 50 is blown through the inside of the ventilation duct 30 and is blown to a portion near the frame 40 on the side where the drive motors 21 and 22 of the CRU 20 are provided. Can see.

  Moreover, the external view at the time of seeing the surroundings of this ventilation duct 30 from the rear side is shown in FIG. Referring to FIG. 6, it can be seen that the air taken in by the blower fan 60 is conveyed upward in the vertical direction and the air flow is changed 90 degrees to the right and sent to the periphery of the drive unit of the CRU 20.

  Next, the external view of only the ventilation duct 30 and the blower fan 60 is shown in FIG.

  Referring to FIG. 7, the blower fan 60 sucks low-temperature air on the back side of the printed wiring board 50 and blows it to the ventilation duct 30, and the air that has passed through the ventilation duct 30 is blown to the CRU 20. I understand.

  FIG. 8 shows the positional relationship between the ventilation duct 30, the printed wiring board 50, and the frame 40. FIG. 8 is a view when the ventilation duct 30 is viewed from the left side of the image forming apparatus 10. Referring to FIG. 8, a part of the ventilation duct 30 constitutes a ventilation pipe together with the frame 40, and the air on the rear side from the frame 40 is ventilated to the CRU 20 located on the front side from the frame 40. I understand.

  Finally, another structure provided for cooling the CRU 20 will be described with reference to FIG.

  Referring to FIG. 9, it can be seen that the blower fan 72, the sheet cooling fans 81 and 82, and the blower fan 60 described above are provided as a configuration for cooling the CRU 20.

  The blower fan 72 is provided to cool the front side of the CRU 20, and blows air taken from an intake hole (louver) 71 provided on the front side of the image forming apparatus 10 to the front side of the CRU 20. Cooling is performed.

  In addition, the paper cooling fans 81 and 82 cool the paper and the CRU 20 by exhausting air in the vicinity of the paper on which image formation is performed in the CRU 20.

  The blower fan 60 described above is provided to cool the rear side of the CRU 20, and blows air in a low temperature atmosphere around the printed wiring board 50 around the frame 40 of the CRU 20 through the air duct 30. The CRU 20 is cooled.

  As can be seen from FIG. 9, the drive motor 21, 22 side of the CRU 20 has a structure in which heat generated by the drive motor 21, 22 and the frame 40 is difficult to escape, and the temperature is likely to be higher than other parts of the CRU 20. It has become.

  In the present embodiment, the blower fan 60 takes in air not from the area where the image forming operation is performed but from the area on the rear side of the frame 40. For this reason, it is difficult to cause a problem that toner adheres to an optical system such as an optical scanning device and a light amount is reduced due to glass contamination.

  Further, in the present embodiment, the region where the ventilation duct 30 sucks air is set below the image forming apparatus 10 by extending the ventilation duct 30 long downward in the vertical direction. Therefore, in the present embodiment, air in a low temperature atmosphere can be taken in.

  This is because the heat distribution in the image forming apparatus 10 becomes higher as it goes upward due to natural convection of heat, so that low-temperature air can be sucked by taking in air from below the apparatus as much as possible. Further, by extending the ventilation duct 30 downward in the vertical direction, the temperature of the air to be taken in is lowered so as not to suck the high-temperature atmosphere around the drive motors 21 and 22.

  Further, since the blower fan 60 for sucking the ventilation duct 30 is provided in the vicinity of the back side of the printed circuit board 50, an air flow is generated around the printed circuit board 50 to cool the printed circuit board 50. Also become.

  Since the temperature around the printed wiring board 50 is lower than the temperature of the driving unit of the image forming unit 20, the air around the printed wiring board 50 is blown to the driving unit of the image forming unit 20, so The drive unit is cooled.

  For example, when the temperature of the CRU 20 is 47 ° C. and the ambient temperature of the printed wiring board 50 is 35 ° C., there is a temperature difference between the ambient temperature of the printed wiring board 50 and the CRU 20. It is possible to cool the drive unit of the CRU 20 using

  In the present embodiment, the blower fan 60 is configured to take in air from the back side of the printed wiring board 50, but depending on the position of the printed wiring board 50, the blower fan 60 may be connected to the front side of the printed wiring board 50 ( It is also possible to take in air from the component side.

  In the present embodiment, no exhaust hole is provided for exhausting air blown from the ventilation duct 30 to the CRU 20 to the outside of the apparatus. However, the air blown from the ventilation duct 30 to the CRU 20 diffuses inside the apparatus after absorbing the heat around the drive unit of the CRU 20.

  Further, when the air around the printed wiring board 50 is sucked by the blower fan 60, low temperature air flows into the periphery of the printed wiring board 50 from a gap in the apparatus. For this reason, cooling of a high temperature part such as a drive part of the CRU 20 is performed by blowing air in a low temperature atmosphere in the apparatus to the high temperature part without providing an intake hole for taking in air from the outside of the image forming apparatus 10. become.

  Furthermore, since the blower fan 60 does not communicate with the outside of the apparatus by not providing the intake holes, the sound generated by the blower fan 60 is prevented from leaking out of the apparatus and the generation of noise is also suppressed.

  By not providing the air intake holes, since the outside air is not directly blown onto the printed wiring board 50, a short circuit of the printed wiring board 50 due to intrusion of dust or the like can be prevented.

[Modification]
In the embodiment described above, the periphery of the printed circuit board 50 is described as a low temperature atmosphere region having a low temperature atmosphere compared to the temperature during operation of the CRU 20, and the case where air in this low temperature atmosphere is blown to the CRU 20 has been described. However, the present invention is not limited to this. When a region having a low temperature atmosphere is present in other regions in the image forming apparatus 10 as compared with the temperature during operation of the CRU 20, the present invention is similarly applied even when air in this low temperature atmosphere is blown to the CRU 20. It is something that can be done.

  Furthermore, although the said embodiment demonstrated using the case where the air of the low temperature atmosphere of the printed wiring board 50 periphery is ventilated to CRU20 which is cooling object, this invention is not limited to this. The present invention can be similarly applied even when a member other than the CRU 20 is cooled as an object to be cooled.

10 image forming apparatus 20 CRU (image forming unit)
21, 22 Drive motor 30 Ventilation duct 40 Frame (metal frame)
50 Printed Circuit Board 60 Blower Fan 71 Intake Hole 72 Blower Fan 81, 82 Paper Cooling Fan

Claims (5)

An image forming unit having an image carrier for holding an image formed by developing the latent image;
A blowing unit for sucking and blowing air in a region having a low temperature atmosphere compared to a temperature during operation of the image forming unit in a region below the image forming unit;
A ventilation path for ventilating the air blown by the blowing means to the image forming unit;
An image forming apparatus.   2. The image forming apparatus according to claim 1, wherein the ventilation path allows the air blown from the blowing unit to pass through a portion of the image forming unit on which the drive motor is attached.   2. The image forming apparatus according to claim 1, wherein the air passage causes the air blown from the blower to pass through a portion of the image forming unit close to a frame for fixing the image forming unit.   4. The image formation according to claim 1, wherein the blowing unit sucks air around a printed wiring board on which an electronic circuit component for controlling an image forming operation is mounted and blows the air to the ventilation path. 5. apparatus.   The image forming apparatus according to claim 1, wherein the blower unit is a blower fan.

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