JP6476792B2 - Optical device and image forming apparatus - Google Patents

Description

  The present invention relates to an optical device provided with a light source and an optical member to which light from the light source is guided, and an image forming apparatus provided with such an optical device. In particular, the optical device has a light source attached to a wall surface of the housing, and an optical member to which light from the light source is directed is attached to a mounting portion provided inside the housing so as to intersect the wall surface. The invention is characterized in that the positional relationship between the light source and the optical member is appropriately prevented from being shifted due to temporal changes such as temperature, and the light source and the optical member are maintained in a constant state. is there.

  Conventionally, in an image forming apparatus comprising a copier, a printer, a facsimile and a composite machine of these, an optical device is mounted, and the photosensitive member is exposed to light according to image information by the optical device to electrostatically It is practiced to form a latent image.

  Then, as such an optical device, as conventionally disclosed in Patent Document 1, a light source is attached to the wall surface of the housing, and light from the light source is transmitted through an optical member such as a collie meter lens to a polygon mirror etc. It is used that is guided to a scanning optical element composed of a rotating polygon mirror, and the light from the light source is guided to the photosensitive member through this scanning optical element.

  Here, when light is emitted from the light source attached to the wall surface of the housing as described above, the light source becomes hot. Therefore, in this patent document 1, the scanning optical element and the light source formed of the rotating polygon mirror are used. It is proposed to provide a guide member between them and direct the flow of air generated by the rotation of the scanning optical element to the light source to cool the light source.

  Further, in Patent Document 2, a fitting portion for holding a light source is provided so as to protrude from a wall surface, an air path is formed in the vicinity of the fitting portion which protrudes in this manner, and the wind is guided to the air path. It has been proposed that heat is dissipated from the fitting portion holding the light source to prevent the wall surface of the housing provided with the light source from being deformed.

  However, in the case where a resin housing molded in a heated state by injection molding or the like is used as the housing, the light source may be provided inside the housing so as to intersect the wall surface of the housing to which the light source is attached. If an attachment is provided to attach an optical member to which light from the light is introduced, heat at the time of molding is not sufficiently dissipated at the intersection where the wall and the attachment intersect, and in particular, the intersection between the wall and the attachment Is located away from the end face of the wall surface, the heat during molding is less likely to be dissipated, and the housing is molded with much heat remaining at the intersection between the wall surface and the mounting portion. The internal stress remains.

  And in such a housing made of resin, when the light source is provided on the wall surface, as shown in the above-mentioned patent documents 1 and 2, the light source is cooled or the heat is dissipated from the fitting part which holds the light source. Even in the case where the light source is attached, the internal stress remaining at the intersection is released due to transportation or temperature rise in the image forming apparatus, etc., and the wall surface to which the light source is attached Of the light source and the optical member, the light from the light source can not be properly guided to the optical member, and the electrostatic latent image can not be properly formed on the photosensitive member. Problem of adversely affecting the image quality.

Japanese Patent Laid-Open No. 6-337365 Unexamined-Japanese-Patent No. 2006-308754

  The present invention is an optical system in which a light source is attached to a wall surface of a housing, and an optical member to which light from the light source is guided is attached to a mounting portion provided inside the housing so as to intersect the wall surface. In the device, the internal stress remaining at the intersection where the wall and the attachment cross each other is released due to a temperature rise or the like, so that the intersection is prevented from being deformed, and the positions of the light source and the optical member It is an object of the present invention to appropriately prevent the relationship from being shifted and to keep the light source and the optical member in a constant state.

In the optical device according to the present invention, in order to solve the above problems, the light source is attached to the wall surface of the housing, and the optical member to which the light from the light source is guided intersects the wall surface. In the optical device attached to the attaching portion provided in the inside of the housing, the housing is provided with at least two openings, and the cold air flow passage for guiding the cold air in the vicinity of the crossing portion between the wall surface and the attaching portion The mounting portion is provided at an intermediate position in the height direction of the wall surface, and the opening is formed in the portion on which the optical member is mounted and the portion on the opposite side through the mounting portion. A portion is provided, and the cold air flow path is formed inside the housing on the side opposite to the side on which the optical member is provided via the mounting portion .

  Then, in this optical device, the cold air is guided through the cold air flow path in the vicinity of the intersection between the wall surface to which the light source is attached and the attaching portion to which the optical member to which light from the light source is directed is attached. .

  Here, in the above-described optical device, in order to form a cold air flow path for guiding cold air to a position close to the intersection between the wall surface provided with the light source and the mounting portion, the opening is used as a housing It is preferable to provide on the wall surface of

  Further, in this optical device, a light source is provided in the vicinity of the intersection between the wall surface to which the light source is attached and the attachment portion to which the optical member to which light from the light source is attached is attached. In addition to guiding cold air to the cold air flow path from the opening provided at a position close to the intersection of the wall surface and the mounting portion, and at a position away from the intersection of the wall surface provided with the light source and the mounting portion It is also possible to guide cold air to the cold air flow path from the provided opening. In order to suppress the rise of the temperature of the cold air before the cold air is led to the intersection through the cold air flow path, the cold air is provided from an opening provided at a position near the intersection. It is preferable to lead it to the cold air flow path.

Then, in the optical device according to the present invention , as described above, the attachment portion is provided at an intermediate position in the height direction of the wall surface, and the portion to which the optical member is attached and the opposite side through the attachment portion portion provided with the opening portion of the interior of the housing at the side opposite to the side where the optical member is provided through the mounting portion, and to form the cold air flow path. Thus, when the cold air flow path is formed inside the housing on the side opposite to the side on which the optical member is provided via the mounting portion, the cold air is directly blown to the light source and the optical member and included in the cold air. Dust and the like attached to the light source and the optical member are prevented from becoming dirty.

  Further, in this optical device, while attaching a plurality of light sources to the wall surface of the housing, attaching portions attaching the respective optical members to which the light from each light source is guided are provided to intersect the wall surface, The intersections with the mounting portions can be made different in the height direction of the wall surface. In this way, the light guided from each light source to each optical member can be appropriately guided from each optical member to each deflection member such as a reflecting mirror.

  And, when the crossing portion between the wall surface and each mounting portion is different in the height direction of the wall surface as described above, when the distance from any end face in the vertical direction of the wall surface to the crossing portion becomes long, In this case, the heat at the time of molding is not sufficiently dissipated, and the housing is molded with a large amount of heat remaining at this intersection, and a large internal stress remains at this intersection.

  For this reason, the intersection where the distance from any end face in the vertical direction of the wall is long is provided at a position close to the opening that guides the cold air to the cold air flow channel so that the temperature of the cold air guided through the cold air flow channel does not rise. Preferably, cold air is introduced to the intersection.

  Further, in order to provide the intersection portion where the distance from any end face in the vertical direction of the wall surface is long as described above to the opening portion for guiding the cold air to the cold air flow path, the wall surface to which a plurality of light sources are attached The crossing portion which is provided to be inclined with respect to the cold air flow channel for guiding the cold air can be made close to the opening for guiding the cold air flow to the cold air channel.

  Further, in the image forming apparatus according to the present invention, when the photosensitive member is exposed by the optical device according to the image information to form an electrostatic latent image on the photosensitive member, the optical device as described above is used. .

  Like the optical device in the present invention, at least two openings are provided in the housing, and a cold portion is provided in the vicinity of the intersection between the wall where the light source is attached and the attachment where the optical member to which light from the light source is directed. By forming a wind flow path and guiding a cold air through the cold air flow path, the cold air appropriately cools the intersection.

  As a result, in the optical device according to the present invention, a wall surface to which a light source is attached and an optical member to which light from the light source is guided are attached like a resin housing molded in a heated state by injection molding or the like. Even if heat remains at the intersection with the mounting portion and internal stress remains at the intersection, as described above, the cold air is guided through the cold air flow path to cool the intersection Even if the temperature etc. changes over time due to a temperature rise in the image forming apparatus, the internal stress remaining at the intersection where the wall and the attachment cross each other is released and the intersection is deformed. Thus, the positional relationship between the light source mounted on the wall surface and the optical member mounted on the mounting portion is maintained constant, and light from the light source is properly guided to the optical member.

  In an image forming apparatus using such an optical device, light from the light source is used to form an electrostatic latent image on the photosensitive member by performing exposure according to image information on the photosensitive member by the optical device. It is stably and appropriately guided to the optical member, an electrostatic latent image is properly formed on the photosensitive member, and a good image can be stably obtained.

FIG. 1 is a schematic cross-sectional view showing an example of an image forming apparatus using an optical device according to an embodiment of the present invention. In the optical device according to the embodiment of the present invention, four light sources are provided on the outer surface side of the wall surface of the corner portion in the housing, and an opening is provided on the wall surface of the corner portion and the wall surface adjacent thereto. FIG. 6 is a partial perspective view showing FIG. In the optical device according to the embodiment, a partial cross-sectional explanatory view showing a state in which four optical members are attached to the lower side of each attachment portion provided inside the housing so as to be orthogonal to the wall surface of the corner portion. is there. In the optical device according to the above-described embodiment, a partial bottom view with a part cut away showing a state in which the light from each light source provided on the outer surface side of the wall surface of the corner is guided to each optical member attached to each attachment It is. In the optical device according to the embodiment, the optical members are provided to face each light source provided on the wall surface of the corner portion, and the opening portion is provided on the wall surface of the corner portion and the wall surface adjacent thereto. It is the partial top view which notched the part which shows. In the optical device according to the above embodiment, cold air is guided to a cold air flow passage in the housing from a first opening provided in a wall surface of the corner portion, and the cold air is provided in a wall surface adjacent to the wall surface of the corner portion It is the fragmentary perspective view which showed the state made to discharge from the opening part of. In the optical device according to the embodiment, the cold air is guided to the cold air flow path in the housing from the second opening provided in the wall surface adjacent to the wall surface of the corner portion, and the cold air is provided in the wall surface of the corner portion It is the fragmentary perspective view which showed the state made to discharge from the opening part of.

  Next, an optical device according to an embodiment of the present invention and an image forming apparatus using the optical device will be specifically described based on the attached drawings. Note that the optical device and the image forming apparatus according to the present invention are not limited to those shown in the following embodiments, and can be appropriately modified and implemented within the scope of the present invention.

  First, an example of an image forming apparatus 1 using an optical device 100 according to an embodiment of the present invention will be described based on FIG.

  Here, in the image forming apparatus 1 shown in FIG. 1, a charging device 12 for charging the surface of the photosensitive member 11 and a developer are provided while providing four photosensitive members 11 inside thereof. And the toner image formed on the photosensitive member 11 is transferred onto the intermediate transfer belt 17 described later, and then the toner remaining on the surface of the photosensitive member 11 is removed. A first cleaning device 14 is provided for collecting.

  Then, in the respective developing devices 13 provided corresponding to the four photosensitive members 11, the color of the toner in the developer is made different, and the toners of black, yellow, magenta and cyan are accommodated.

  When the image forming apparatus 1 performs full-color image formation, the photosensitive members 11 are rotated to charge the surfaces of the photosensitive members 11 by the charging device 12 and thus charged. The surface of each photosensitive member 11 is exposed according to image formation information from an optical device 100 to be described later, and electrostatic latent images are formed on the surface of each photosensitive member 11.

  Then, for each photosensitive member 11 on which the electrostatic latent image is formed in this way, toner of a predetermined color is supplied from the corresponding developing device 13 to the electrostatic latent image portion of each photosensitive member 11 for development. To form a toner image of each color on the surface of each photosensitive member 11.

  As described above, the toner images of the respective colors formed on the respective photosensitive members 11 are bridged between the rotating rollers 16 provided at predetermined intervals and the endless intermediate transfer belt 17 is rotationally driven. The primary transfer roller 18 is provided on the surface to sequentially transfer primary images by the respective primary transfer rollers 18 provided opposite to the respective photosensitive members 11, and a toner image in which toner images of respective colors are combined on the surface of the intermediate transfer belt 17 is I am trying to form. Further, the toner remaining on the surface of each photosensitive member 11 without being transferred to the intermediate transfer belt 17 is provided from the surface of each photosensitive member 11 by the first cleaning device 14 provided correspondingly. I am trying to collect it.

  The toner image formed on the intermediate transfer belt 17 as described above is guided by the intermediate transfer belt 17 to a position facing the secondary transfer roller 19, and the sheet S accommodated in the lower portion of the apparatus main body 1 Are fed by the feed roller 21 and sent to the timing roller 22, and the sheet S is guided between the intermediate transfer belt 17 and the secondary transfer roller 19 at an appropriate timing by the timing roller 22. The toner image formed on the upper side is transferred onto the sheet S by the secondary transfer roller 19 described above. Further, the toner remaining on the intermediate transfer belt 17 without being transferred to the sheet S is collected from above the intermediate transfer belt 17 by the second cleaning device 20.

  Then, the sheet S on which the toner image has been transferred as described above is guided to the fixing device 23, and the toner image transferred onto the sheet S by the fixing device 23 is heat-fixed on the sheet S. The sheet S on which the image is fixed is discharged by the discharge roller 24.

  Next, an optical device 100 according to an embodiment of the present invention will be described.

  Here, in the optical device 100 according to this embodiment, as shown in FIGS. 2 to 5, four light sources 101 a to 101 d are provided on the outer surface side of the wall surface 111 a of the corner portion taken off in the wall surface 111 of the housing 110. The light source holders 102a to 102d are attached at predetermined intervals in the lateral direction and height direction of the wall surface 111a. Further, the wall surface 111a and the optical axis are held in a state where the four optical members 103a to 103d formed of a collie meter lens are held by the holder members 104a to 104d so as to face the respective light sources 101a to 101d. Are attached to the lower side of the attachment portions 105a to 105d provided inside the housing 110 so as to be orthogonal to the direction of.

  Here, a portion where each attachment portion 105a to 105d intersects with the wall surface 111a is referred to as an intersection portion, but "crossing" means that each attachment portion 105a to 105d is on one surface side of the wall surface 111a as shown in FIGS. It does not necessarily show that each attachment part 105a-105d protrudes to the back side of the wall surface 111a including the shape which protrudes only.

  Then, in the optical device 100 of this embodiment, light is emitted from the light sources 101a to 101d toward the corresponding optical members 103a to 103d, and light from the light sources 101a to 101d is emitted from the optical members 103a. Through 103 d, and the thus treated light is deflected by a deflecting member (not shown) such as a reflecting mirror and guided to a scanning optical element (not shown) such as a polygon mirror, and from this scanning optical element Each photosensitive member 11 provided in the image forming apparatus 1 is exposed according to the image information.

  Here, in the optical device 100 of this embodiment, the distance ha to h in the height direction from the upper surface 112 of the wall surface 111a of the housing 110 to each intersection portion where the attachment portions 105a to 105d are provided is And a fourth optical member 103d attached to the fourth light source 101d in order from the first attachment portion 105a attached to the first optical member 103a facing the first light source 101a. It becomes short as it goes to attaching part 105d.

  Then, in such an optical device 100, when the resin made of a resin molded in a heated state by injection molding or the like is used as the housing 110, the wall surface 111a of the corner portion and the mounting portion 105a At the intersection with -105 d, the heat at the time of molding is not sufficiently dissipated, and the internal stress remains at this intersection. In particular, as the distance between the upper surface 112 of the wall surface 111a of the corner portion and the intersection with the mounting portions 105a to 105d increases, the influence of the release of the internal stress increases and the distance from the upper surface 112 of the wall surface 111a increases. At the intersection with the mounting portion 105a in the second position, the influence of the internal stress at the release is the largest.

  Then, in such an optical device 100, when the temperature at the intersection of the wall surface 111a and the mounting portions 105a to 105d changes due to a temperature rise in the image forming apparatus 1 or the like, it remains at the intersection. The internal stress is released, the intersection is deformed, and the positional relationship between the light sources 101a to 101d and the optical members 103a to 103d shifts, and the light from the light sources 101a to 101d is properly applied to the optical members 103a to 103d. I will not be guided.

  Therefore, in the optical device 100 according to this embodiment, the corner portion on the opposite side to the surface on which the optical members 103a to 103d are attached in the attachment portions 105a to 105d, that is, the corner portion above the attachment portions 105a to 105d. The first opening 113a is provided on the upper surface side of the wall surface 111a, and the second wall 111b adjacent to the wall surface 111a of the corner portion is provided on the side where the mounting portion 105a having the large distance ha is provided. An opening 113b is provided away from the first opening 113a, and a first opening is formed inside the housing 110 on the opposite side to the optical members 103a to 103d through the mounting portions 105a to 105d. A cold air flow passage L is provided which guides cold air through the portion 113a and the second opening 113b.

  Here, when the cold air flow path L is thus provided inside the housing 110 on the opposite side to the optical members 103a to 103d through the attachment portions 105a to 105d, the cold air is directly applied to the optical members 103a to 103d. Even if the cold air contains dust and the like without being led to the light sources 101a to 101d, dust and the like adhere to the optical members 103a to 103d and the light sources 101a to 101d, and the optical members 103a to 103d and the light sources There is no possibility of the soiling of 101a to 101d.

  And, in the optical device 100 of this embodiment, for example, as shown in FIG. 6, cold air is passed through the first opening 113a provided on the wall surface 111a of the corner where the light sources 101a to 101d are attached. The cool air flow path L in the housing 110 is introduced, and the cool air is cooled after the intersections between the wall surface 111a and the mounting portions 105a to 105d provided with the optical members 103a to 103d are cooled. The cold air flow path L is discharged from the second opening 113 b.

  In this way, even when the temperature in the image forming apparatus 1 rises, the cold air introduced from the first opening 113a to the cold air flow path L in the housing 110 is promptly transmitted to the wall surface 111a. Optical members 103a to 103d are guided to the intersections with the mounting portions 105a to 105d, so that the intersections are properly cooled and deformation of the intersections is appropriately prevented. And the positional relationship between the light sources 101a to 101d and the optical members 103a to 103d is kept constant, and the light from the light sources 101a to 101d is appropriately guided to the optical members 103a to 103d, Good image formation can be stably performed.

  In the optical device 100 according to this embodiment, as shown in FIG. 7, the wall surface 111b adjacent to the wall surface 111a of the corner portion is provided at a position away from the first opening 113a. The cold air is guided to the cold air flow path L in the housing 110 through the opening 113b of 2, and the intersection between the wall surface 111a and the mounting portions 105a to 105d provided with the optical members 103a to 103d by the cold air. It is possible to discharge the cold air from the first opening 113a after cooling the air etc.

  In this case, the distance between the intersection of the wall surface 111a of the corner and each of the mounting portions 105a to 105d provided with the optical members 103a to 103d and the second opening 113b is the wall surface 111a. In order from the intersection where the mounting portion 105a having a large distance ha from the upper surface 112 of the second embodiment is provided, the distance is closer in order. That is, since the mounting portions 105a, 105b, 105c, and 105d are sequentially located from the upstream side along the cold air flow path L, the cold air guided to the cold air flow path L in the housing 110 from the second opening 113b is a distance Guided in order from the intersection where the mounting portion 105a having a large ha is provided, the internal stress remaining in the intersection is properly cooled in order from the intersection having the large internal stress. Therefore, deformation of these intersections is appropriately prevented, and the positional relationship between each of the light sources 101a to 101d and each of the optical members 103a to 103d is maintained constant, and from each of the light sources 101a to 101d. The light is appropriately guided to each of the optical members 103a to 103d so that good image formation can be stably performed.

  In the optical device 100 according to the embodiment, the first opening 113a and the second opening 113b are provided in the wall surface 111a of the corner portion and the wall surface 111b adjacent thereto. Alternatively, at least one of the opening 113 a and the second opening 113 b may be provided on the top surface 112 of the housing 110.

1: Image Forming Device 11: Photosensitive Member 12: Charging Device 13: Developing Device 14: First Cleaning Device 16: Rotating Roller 17: Intermediate Transfer Belt 18: Primary Transfer Roller 19: Secondary Transfer Roller 20: Second Cleaning Device 21 A sheet feeding roller 22: a timing roller 23: a fixing device 24: a sheet discharging roller 100: an optical device 101a to 101d: a light source 102a to 102d: a light source holder 103a to 103d: an optical member 104a to 104d: a holder member 105a to 105d: a mounting portion 110: Housing 111: Wall surface 111a: Wall surface 111b of corner portion: Wall surface 112 adjacent to corner portion: Top surface 113a: First opening portion 113b: Second opening portion L: Cold air flow path S: Paper ha to hd: Corner Height from the top of the wall of the section to the intersection Distance of

Claims (8)

The optical device has a light source attached to a wall surface of the housing, and an optical member to which light from the light source is directed is attached to a mounting portion provided inside the housing so as to cross the wall surface. of at least two openings provided in the housing, around to form a cool air passage for guiding the cool air in the vicinity of the intersection between the wall and the mounting portion within the housing, the high the mounting portion of the wall The opening is provided at an intermediate position in the longitudinal direction, and the opening is provided in the part to which the optical member is attached and the part on the opposite side via the attachment, and the optical member is provided through the attachment. It was in the housing on the opposite side to the side, the optical device comprising the this formed with the cold air flow path.   The optical device according to claim 1, wherein the opening is provided on a wall surface of the housing.   The optical device according to claim 1 or 2, wherein cold air is guided to the cold air flow path through an opening at a position close to the intersection of the wall surface provided with the light source and the attachment portion. apparatus.   The optical device according to claim 1 or 2, wherein cold air is guided to the cold air flow path through an opening at a position separated from the intersection of the wall surface provided with the light source and the attachment portion. Optical device. The optical device according to any one of claims 1 to 4 , wherein a plurality of light sources are attached to a wall surface of the housing, and each attachment portion to which each optical member to which light from each light source is guided is attached is the wall surface An optical device characterized in that the intersection between the wall surface and each mounting portion is different in the height direction of the wall surface. The optical device according to claim 5, characterized in that the intersecting portion where the distance from any end face in the vertical direction of the wall surface is long is provided at a position near the opening for guiding the cold air to the cold air flow passage. Optical device to be. The optical device according to claim 6 , wherein the wall surface to which a plurality of light sources are attached is provided to be inclined with respect to a cold air flow channel for guiding cold air. An image forming apparatus for forming an electrostatic latent image on a photosensitive member by performing exposure according to image information on a photosensitive member by an optical device, the optical device according to any one of claims 1 to 7 being used. An image forming apparatus characterized by

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