JP5255795B2 - Image forming apparatus - Google Patents

Description

  The present invention relates to an image forming apparatus such as a printer, a copier, a facsimile machine, or a multifunction machine having these functions.

  In recent image forming apparatuses such as printers, copiers, facsimile machines, scanners, or multifunction machines equipped with these functions, in particular, in electrophotographic image forming apparatuses, an image of a photosensitive member or the like using a laser writing device. Generally, an electrostatic latent image formed on a carrier is formed.

  At this time, the laser writing device is generally arranged in a main body of the image forming apparatus while securing a laser light path.

  In addition, the laser writing device is located in the image forming apparatus, whether it is a dedicated machine such as a printer, a copying machine, a facsimile machine, a multi-function machine, a monochrome machine or a full-color machine, etc. Although it differs depending on the layout of the image forming unit determined by the grade etc., it is often arranged at the upper part or the lower part (particularly directly above or directly below) of the image carrier (see, for example, Patent Document 1).

The laser writing device reflects a laser beam emitted from a laser light source on a polygon mirror based on image data that is a source of image formation, and irradiates and forms an image on the image carrier with the reflected light. Although an image is formed, these optical systems are arranged in a casing to be in a unit state (for example, see Patent Document 2).
Japanese Patent Application Laid-Open No. 06-043723 JP 2007-171296 A

  On the other hand, with the recent increase in the image forming processing speed, the rotation speed of the polygon mirror is also increased, and it is impossible to ignore the generation of rotating sound and the temperature rise caused by the polygon mirror.

  Therefore, in Patent Document 1 described above, the air writing path is actively formed to cool the laser writing device.

  However, such a cooling structure is complicated, and in particular, in a full-color image forming apparatus, each color (for example, yellow (Y), magenta (M), cyan (C), black ( Since the laser writing device and the image carrier corresponding to K)) are arranged, it is complicated to guide the outside air taken in by one cooling fan to each laser writing device with a duct. As a result, there is a problem that it is difficult not only to increase the size of the apparatus body but also to take in sufficient outside air.

  In the above cited reference 1, the image forming unit and the laser writing device are fixed between a pair of side plates constituting a part of the inner wall of the apparatus main body.

  At this time, since the uppermost edges of the pair of side plates are located higher than the upper surface of the laser writing device, when a wind flow is generated by a rotating fan in an attempt to cool the laser writing device that has accumulated heat by high rotation of the polygon mirror, As a result, there is a side plate at the intake / exhaust position of the rotary fan, resulting in a problem that the cooling efficiency is hindered.

  Accordingly, an object of the present invention is to provide an image forming apparatus capable of improving the cooling efficiency and soundproofing of a laser writing device while having a simple configuration in consideration of the above circumstances.

  An image forming apparatus of the present invention includes an image reading unit that generates image data, a laser light source that emits laser light based on the image data generated by the image reading unit, and laser light emitted from the laser light source. A polygon mirror that deflects in the scanning direction, an imaging lens that forms an image of the laser light deflected by the polygon mirror, an oblique mirror that reflects the laser light imaged by the imaging lens, and the oblique mirror An image carrier disposed oppositely, a mirror cover that covers the polygon mirror, a casing that covers the optical system from the laser light source to the oblique mirror in a unit state, and a base that supports the bottom surface of the casing; A peripheral wall surrounding the housing, and the peripheral wall is provided with an opening so as to be positioned between the image reading unit and the base.

  In this case, it is preferable that the image carrier is disposed below the base.

  Moreover, it is preferable that a cooling fan facing the casing is provided on the peripheral wall.

  The image forming apparatus of the present invention can improve the cooling efficiency and soundproofing of the laser writing apparatus while having a simple configuration.

  Next, an image forming apparatus according to an embodiment of the present invention will be described with reference to the drawings.

  FIG. 1 is a front view of a multifunction peripheral as an image forming apparatus according to an embodiment of the present invention, FIG. 2 is an explanatory diagram of an arrangement relationship in the image forming apparatus according to an embodiment of the present invention, and FIG. FIG. 4 is an explanatory view of the arrangement relationship of main parts in the image forming apparatus according to the embodiment, FIG. 4 is an explanatory view before duct piping of the cooling structure in the image forming apparatus according to the embodiment, and FIG. 5 is an embodiment of the invention. FIG. 6 is an exploded perspective view of a laser writing device used in the image forming apparatus according to the embodiment of the present invention, and FIG. It is a top view of the principal part of the laser writing apparatus used for the image forming apparatus which concerns on one Embodiment.

  As shown in FIG. 1, a multifunction machine 1 as an image forming apparatus according to an embodiment of the present invention is provided with sheet feeding cassettes 3, 4, 5, 6 for storing transfer sheets provided in the apparatus body 2 so as to be drawable. An automatic document feeder (ADF) 7 for placing a document when the multifunction device 1 is used as a copying machine or a scanner, an operation unit 9 for performing various operations in combination with a touch panel type liquid crystal display 8, and an image. And a paper discharge tray 10 for collecting the transfer paper after the forming process.

  As shown in FIGS. 2 to 5, the apparatus body 2 receives image data of a document sent out by the ADF 7 or print data transmitted from a personal computer (not shown) or a telephone line (FAX). An image reading unit 11 that generates image data, a laser writing device 12 that emits laser light based on the image data, and a photosensitive member that is disposed below the laser writing device 12 and irradiated with the emitted laser light An image carrier 13 such as a drum, a pair of side plates 14 and 15 disposed so as to constitute part of an inner wall (peripheral wall) of the apparatus main body 2, and a base 16 fixed to the upper side of the side plates 14 and 15. And a support column 17 that rises from the side plates 14 and 15 or the base 16 and supports the image reading unit 11 at the upper end thereof.

  The side plates 14 and 15 are arranged before and after the apparatus main body 2, that is, at both ends of the image carrier 13 when the operation unit 9 side is the front surface. Further, the upper ends of the side plates 14 and 15 are partly lower than the upper surface of the laser writing device 12 so as to have an opening 18 between the image reading unit 11 and the base 16. . Further, a cooling fan 19 is provided on the side plate 14 so as to face each laser writing device 12. The height of the cooling fan 19 is substantially the same as the distance between the image reading unit 11 and the base 16. A duct 20 fixed to the base 16 is disposed between the back side of the cooling fan 19 and the side plate 15. A part of the laser writing device 12 is located in the middle of the duct 20.

  The support column 17 has a columnar shape or a prismatic shape, is raised from the side plates 14 and 15 near the four corners in the apparatus main body 2, or the base 16, and supports the image reading unit 11 on each upper surface. Further, the height of the support column 17 is set to a height that supports the image reading unit 11 at least flush with the upper surface of the laser writing device 12.

  In the present embodiment, a laser writing device 12 and an image carrier 13 corresponding to each color (for example, yellow, magenta, cyan, black) are disposed as the full-color multifunction peripheral 1. Further, since the function and configuration of the image reading unit 11 are known, a detailed description thereof will be omitted.

  As shown in FIGS. 6 and 7, the laser writing device 12 includes a laser light source 21 that emits laser light based on image data by a writing control circuit (not shown), and laser light emitted from the laser light source 21. The polygon mirror 22 that deflects the laser beam in the scanning direction, the imaging lenses 23 and 24 that image the laser light deflected by the polygon mirror 22, and the laser light imaged by the imaging lenses 23 and 24 on the image carrier 13 An oblique mirror 25 that reflects the light, a mirror cover 26 that covers the polygon mirror 22, and a casing 27 that covers the optical system from the laser light source 21 to the oblique mirror 25 in a unit state.

  More specifically, the laser light source 21 modulates the image data into laser light and emits it. The laser light emitted from the laser light source 21 is converted into parallel light by lenses 28 and 29 configured by, for example, a collimator lens and a prism.

  The polygon mirror 22 is formed in a regular hexagonal flat plate shape in plan view, and the laser beam transmitted through the lens 29 is coupled while rotating in a predetermined direction (counterclockwise arrow direction in FIG. 7) by a motor drive (not shown). It is configured to deflect toward the image lens 23.

  The imaging lenses (for example, fθ lenses) 23 and 24 are disposed at appropriate positions in the casing 27 so that their arch portions face each other, and the laser beam deflected by the polygon mirror 22 is applied to the image carrier 13. It has a function of scanning at a constant speed.

  The oblique mirror 25 is provided to guide the laser light from the imaging lens 24 to the image carrier 13 through the opening 27 a of the housing 27.

  The mirror cover 26 is formed with an opening 26 a so as to guide the laser light emitted from the laser light source 21 to the polygon mirror 22 and guide the laser light deflected by the polygon mirror 22 to the imaging lens 23. Yes. Further, the mirror cover 26 covers the periphery and the upper part of the polygon mirror 22 except for the opening 26 a, thereby making it difficult for the rotational sound generated due to the high-speed rotation of the polygon mirror 22 to leak into the housing 27. ing.

  The casing 27 is open at the top and is closed by a cover 30. The casing 27 has a multi-radiating fin 27b formed in the vicinity of the bottom surface where the polygon mirror 22 is disposed. The cooling fan 19 is preferably arranged at a position facing the multi-radiating heat radiation fins 27b, and the cooling fan 19 is arranged by arranging the fin arrangement direction of the multi-radiating heat radiation fins 27b along the left-right direction of the apparatus main body 2. A wide contact area with the cooling air from the can be ensured. In addition, by positioning the multi-row heat radiation fins 27b in the middle of the duct 20, a more efficient cooling structure can be obtained.

  In the laser writing device 12 having such a configuration, the laser light emitted from the laser light source 21 is guided to the polygon mirror 22 through the lenses 28 and 29. Then, the laser light incident on the rotating polygon mirror 22 is reflected and deflected by the mirror surface of the polygon mirror 22 and then reflected by the oblique mirror 25 through the imaging lenses 23 and 24, thereby causing the laser light in a predetermined scanning direction. It is guided to an exposure position on the image carrier 13 that rotates around an axis perpendicular to the scanning direction while being horizontally scanned. Since the polygon mirror 22 is configured to rotate at a constant speed, laser light that passes through the imaging lenses 23 and 24 and reaches the surface of the image carrier 13 travels on the image carrier 13 at a constant speed. To remove the charge on the image carrier 13 and form an electrostatic latent image.

  Then, sound leakage such as a rotating sound and heat generation associated with high-speed rotation of the polygon mirror 22 when forming the electrostatic latent image are suppressed in units of the mirror cover 26 and the housing 27, and thus the image Even if the opening 18 is formed between the reading unit 11 and the base 16, sound leakage from the opening 18 is prevented.

  Accordingly, the heat generated in the multi-strip radiating fins 27 b and the other casings 27 is made between the image reading unit 11 and the base 16 by making the upper ends of the side plates 14 and 15 lower than the upper surface of the laser writing device 12. It is possible to efficiently discharge from the opening 18 formed in.

  As described above, according to the multifunction machine 1 as the image forming apparatus of the present invention, the image reading unit 11 that generates image data, and the laser light source that irradiates laser light based on the image data generated by the image reading unit 11. 21, a polygon mirror 22 that deflects laser light emitted from the laser light source 21 in the scanning direction, imaging lenses 23 and 24 that image the laser light deflected by the polygon mirror 22, and imaging lenses 23 and 24 The oblique mirror 25 that reflects the laser light imaged in FIG. 1, the image carrier 13 that is disposed opposite to the oblique mirror 25, the mirror cover 26 that covers the polygon mirror 22, and the laser light source 21 to the oblique mirror 25. A housing 27 that covers the optical system in a unit state, a base 16 that supports the bottom surface of the housing 27, and side plates 14 and 15 as peripheral walls surrounding the housing 27 are provided. At the same time, the opening 18 is formed so as to be positioned between the image reading unit 11 and the base 16, thereby improving the cooling efficiency and soundproofing of the laser writing device 12 with a simple configuration. Can do.

  In the above embodiment, the image forming apparatus of the present invention has been applied to the full-color multifunction peripheral 1. Of course, it can be applied.

1 is a front view of a multifunction peripheral as an image forming apparatus according to an embodiment of the present disclosure. FIG. 4 is an explanatory diagram of an arrangement relationship in the image forming apparatus according to an embodiment of the present invention. FIG. 3 is an explanatory diagram of an arrangement relationship of main parts in an image forming apparatus according to an embodiment of the present invention. It is explanatory drawing before duct piping of the cooling structure in the image forming apparatus which concerns on one Embodiment of this invention. It is explanatory drawing after duct piping of the cooling structure in the image forming apparatus which concerns on one Embodiment of this invention. 1 is a simplified exploded perspective view of a laser writing device used in an image forming apparatus according to an embodiment of the present invention. It is a top view of the principal part of the laser writing apparatus used for the image forming apparatus which concerns on one Embodiment of invention.

Explanation of symbols

1 ... Multifunction machine (image forming device)
DESCRIPTION OF SYMBOLS 2 ... Apparatus main body 11 ... Image reading unit 12 ... Laser writing apparatus 13 ... Image carrier 14 ... Side plate (peripheral wall)
15 ... Side flight (peripheral wall)
DESCRIPTION OF SYMBOLS 16 ... Base 17 ... Support | pillar 18 ... Opening 21 ... Laser light source 22 ... Polygon mirror 23 ... Imaging lens 24 ... Imaging lens 25 ... Oblique mirror 26 ... Mirror cover 27 ... Housing

Claims (3)

A full-color image forming apparatus,
For deflecting the image reading unit generates image data, and the respective color laser light source for irradiating a laser beam based on image data generated by the image reading unit, the laser light emitted from the respective laser light sources in the scanning direction A polygon mirror, an imaging lens that forms an image of the laser light deflected by the polygon mirror, an oblique mirror that reflects the laser light imaged by the imaging lens, and each color that is disposed opposite to the oblique mirror An image carrier, a mirror cover that covers the polygon mirror, a plurality of cases that cover the optical system from the laser light source to the oblique mirror in a unit state for each color, and a base that supports the bottom surface of the case And a peripheral wall surrounding the housing,
The peripheral wall is provided with an opening so as to face between the image reading unit and the base, and a plurality of ducts are arranged in parallel in the peripheral wall so as to correspond to the housings ,
Each cooling fan at one end of the respective duct is al provided through the one surface of the peripheral wall, each housing respectively an intermediate portion of the respective duct is interposed, the other end of the respective duct peripheral wall is open in a portion of the opening located on the opposite side of one surface of the space around the duct and the housing, the other ends of the duct respectively between and adjacent the cooling fan adjacent The image forming apparatus is opened at a portion other than a portion of the opening between the two .   The image forming apparatus according to claim 1, wherein the image carrier is disposed below the base.   The image forming apparatus according to claim 1, wherein a cooling fan facing the housing is provided on the peripheral wall.

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