JP2012118250A - Reflecting mirror holder, optical scanner, and image forming apparatus - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a reflecting mirror holder that holds a reflecting mirror with curves thereof flattened, an optical scanner including the reflecting mirror holder, and an image forming apparatus including the optical scanner.SOLUTION: A reflecting mirror holder is provided with a support member that supports a mirror surface side of the reflecting mirror, a pressure member that presses and supports the rear side of the mirror surface of the reflecting mirror, and a press-in member that presses in the mirror surface side or the rear side of the reflecting mirror. The support member and the pressure member are respectively provided at both ends the reflecting mirror holder, and the press-in member is provided one end of the reflecting mirror holder.

Description

  The present invention relates to a reflecting mirror holder that holds a reflecting mirror, an optical scanning device that includes the reflecting mirror holder, and an image forming apparatus that includes the optical scanning device.

  An image forming apparatus using an electrophotographic system forms a latent image on a charged photoreceptor (image carrier) by an optical scanning device that forms a laser beam corresponding to image information, and the latent image is developed. The developed image is transferred to a recording medium, and an image is formed on the recording medium.

  In recent years, full-color printing of documents has progressed, and an image forming apparatus that forms a full-color image by an electrophotographic method is used. The full-color image forming apparatus forms a developed image for each color of yellow (Y), magenta (M), cyan (C), and black (Bk), and sequentially transfers the developed image of each color to a recording medium to form a full-color image. is doing.

  The full-color image forming apparatus has a tandem method in which a developed image of each color is transferred to a recording medium by a plurality of independent photoconductors for each color, and four cycles in which the developed image of each color is sequentially transferred to a recording medium by one photoconductor. There is a method.

  In the tandem method, a developed image of each color is formed on a recording medium, and the formed developed image of each color is continuously transferred to the recording medium. In the 4-cycle method, a single color development image is transferred to a recording medium at a time. For this reason, in the tandem method, an image is formed on the recording medium about four times faster than the four-cycle method. As described above, since an image is formed on a recording medium at a high speed, a tandem method is widely used in full-color image forming apparatuses.

  The tandem full-color image forming apparatus includes a plurality of photoconductors corresponding to colors of yellow (Y), magenta (M), cyan (C), and black (Bk), and a plurality of light beams corresponding to the colors. And an optical scanning device to be formed.

  In the full-color image forming apparatus, since a latent image corresponding to each color is formed by a plurality of light beams corresponding to each color, a color shift occurs due to the shift of the light beam.

  Various full-color image forming apparatuses that correct color misregistration by correcting misalignment of light beams have been proposed (see, for example, Patent Document 1). A full-color image forming apparatus described in Patent Document 1 includes a plurality of photosensitive drums corresponding to each color of yellow (Y), magenta (M), cyan (C), and black (Bk), and the plurality of photosensitive drums. And an optical scanning device that emits a light beam corresponding to each color.

  The optical scanning device includes a laser light source such as a semiconductor laser, a polygon mirror that scans the light beam emitted from the laser light source at an equal angle, and an fθ lens that scans the light beam scanned at an equal angle by the polygon mirror at a constant velocity linearly. And a reflecting mirror that reflects the light beam that has been linearly scanned at a constant speed by the fθ lens toward the photosensitive drum.

  In the optical scanning device, as shown in FIG. 23, the reflecting mirrors 204 of the optical scanning device are supported by brackets 202 that support both ends of the reflecting mirror 204. The bracket 202 is provided with clips 207 and 208 that press both ends of the reflecting mirror 204, and a pressing member 203 that presses the center of the reflecting mirror in a direction perpendicular to the mirror surface.

  However, in the image forming apparatus described in Patent Document 1, as shown in FIG. 24, the reflecting mirror 204 is deformed into a convex shape at the center of the reflecting mirror 204, and the peripheral portion of the reflecting mirror 204 is concave. It becomes a substantially M-shape deformed to. For this reason, the scanning line of the light beam reflected by the reflecting mirror 204 is deformed, causing a color shift.

  In addition, since the reflecting mirrors 204 arranged opposite to each other face each other in the bending direction, the scanning lines of the light beams reflected by the plurality of reflecting mirrors 204 are not corrected, and the color shift is not corrected. .

  Further, when external vibration is transmitted to the reflecting mirror 204, a standing wave is formed with the clips 207, 208 and the support portion 205 as nodes, and a resonance phenomenon in which the standing waves strengthen each other occurs, and is transferred to the recording medium. A problem such as banding occurs in the recorded image.

  It is an object of the present invention to provide a reflecting mirror holder that flattenes and holds the curvature of the reflecting mirror, an optical scanning device that includes the reflecting mirror holder, and an image forming apparatus that includes the optical scanning device. .

  In order to solve the above problems and achieve the object, the invention described in claim 1 is directed to a light source that emits a light beam, a light beam emitted from the light source, deflected in the main scanning direction and in the main scanning direction. The reflecting mirror in an optical scanning device having scanning means for scanning, and a reflecting mirror that deflects the main scanning direction in the main scanning direction and reflects the light beam scanned in the main scanning direction by the scanning means is held. It is a reflector holder, and (a) the reflector holder has a support member for supporting the mirror surface side of the reflector, and a pressing member for pressing and supporting the back surface side of the mirror surface of the reflector, And (b) the support member and the pressing member are provided at both ends of the reflecting mirror holder, respectively, and (c) the pressing member that pushes the mirror surface side or the back surface side of the reflecting mirror is provided. The pushing member is It is a reflection mirror holder, characterized in that provided on one end of Ikyo holder.

  The invention described in claim 2 is characterized in that the reflecting mirror holder is provided with adjusting means for adjusting the reflection direction of the light beam by adjusting the inclination of the reflecting mirror. The reflector holder according to 1.

  The invention described in claim 3 is characterized in that the pushing member is provided closer to the center of the reflector holder than the support member. It is a holding tool.

  According to a fourth aspect of the present invention, the pressing member is provided on the center side of the reflecting mirror holder relative to the support member or on the end side of the reflecting mirror holder relative to the support member. It is a reflector holder as described in any one of Claims 1-3 characterized by the above-mentioned.

  In the invention described in claim 5, the pushing member is provided in a range of 1 / 4L <1 / 2L or 1 / 2L <3 / 4L with respect to the total length L of the reflecting mirror. The reflector holder according to any one of claims 1 to 4, wherein the reflector holder is described above.

  The invention described in claim 6 is the reflector holder according to any one of claims 1 to 5, wherein a plurality of the pushing members are provided in the reflector holder. It is.

  The invention described in claim 7 is the reflector holder according to any one of claims 1 to 6, wherein the pressing member is fixed by a fixing means.

  The invention described in claim 8 is the reflector holder according to claim 7, wherein the fixing means is a photo-curing adhesive.

  According to a ninth aspect of the present invention, there is provided a light source that emits a light beam, a scanning unit that deflects the light beam emitted from the light source in the main scanning direction and scans in the main scanning direction, and main scanning by the scanning unit. 9. An optical scanning apparatus comprising: a reflecting mirror that deflects in the main scanning direction and reflects a light beam scanned in the main scanning direction, wherein the reflecting mirror is any one of claims 1 to 8. It is held by the reflector holder described in 1. above.

  According to a tenth aspect of the present invention, there is provided an optical scanning device according to the ninth aspect, a latent image carrier on which a latent image is formed by a light beam emitted from the optical scanning device, and the latent image carrier. An image forming apparatus comprising: a developing unit that develops the formed latent image.

  According to the invention described in claim 1, the reflecting mirror holder includes a supporting member that supports the reflecting mirror at both ends of the reflecting mirror holder, and a pressing member that presses and supports the reflecting mirror, Is provided. For this reason, the reflecting mirror is supported by the support member and the pressing member and is deformed into a curved shape.

  Furthermore, the reflecting mirror holder is provided with a pushing member for pushing the reflecting mirror at one end. For this reason, a pushing member is pushed in the direction in which a reflective mirror opposes a curving direction, and the central part of a mirror surface is flattened. Therefore, the scanning line of the light beam reflected by the central part of the mirror surface is linearized.

  According to the second aspect of the invention, since the inclination of the reflecting mirror is adjusted by the adjusting means, the inclination of the scanning line of the light beam is corrected.

  According to the third aspect of the present invention, the pushing member is provided closer to the center of the reflector holder than the support member. For this reason, the space | interval of a support member and a pushing member becomes narrower than the space | interval of the support member provided in both ends, and a support member. Therefore, when vibration from the outside is transmitted to the reflecting mirror, the natural frequency having the support member and the pushing member as nodes becomes higher than the natural frequency having the support member and the support member as nodes. As a result, the deviation of the scanning line of the light beam when vibration is transmitted to the reflecting mirror is reduced.

  According to the invention described in claim 4, the pressing member is provided on the center side of the reflector holder relative to the support member, or on both ends of the reflector holder relative to the support member. For this reason, the curved shape of the reflecting mirror supported by the support member and the pressing member is deformed into a substantially U shape or deformed into a substantially inverted U shape. Therefore, by using a reflecting mirror deformed into a substantially U shape and a reflecting mirror deformed into a substantially inverted U shape as a pair, and by reflecting the scanning line of the light beam by these reflecting mirrors, Scan line deformation is suppressed.

  According to the fifth aspect of the present invention, the length from one end of the reflecting mirror to the pushing member and the length from the other end of the reflecting mirror to the pushing member are relative to the natural frequency λ of the reflecting mirror. Therefore, the length is not an integral multiple of λ / 2. For this reason, when vibration from the outside is transmitted to the reflecting mirror, vibration with one end of the reflecting mirror and the pushing member as a node, and vibration with the other end of the reflecting mirror and the pushing member as the node , Reinforce each other and prevent resonance.

  According to the invention described in claim 6, a plurality of pushing members are provided in the reflecting mirror holder. For this reason, the curved shape of the reflecting mirror is adjusted in more detail. Moreover, since a plurality of nodes are formed by the plurality of pushing members, the natural frequency of the reflecting mirror further increases.

  According to the invention described in claim 7, since the pushing member is fixed, the corrected state of the reflecting mirror is stably maintained.

  According to the eighth aspect of the present invention, after the adjustment of the pressing member, the periphery of the pressing member is irradiated with light, and the pressing member is fixed. Therefore, there is no possibility that the adjustment of the pushing member is changed in order to apply the adhesive after the pushing member is adjusted.

  According to the ninth aspect of the invention, an optical scanning device in which the scanning line of the light beam is linearized is obtained. Further, an optical scanning device having excellent vibration resistance can be obtained.

  According to the invention described in claim 10, it is possible to provide an image forming apparatus in which occurrence of defects such as color misregistration and banding is prevented.

1 is a schematic configuration diagram of an image forming apparatus according to an embodiment of the present invention. It is a block diagram of the laser scanner of the image forming apparatus shown in FIG. FIG. 3 is a plan view showing a reflecting mirror and a reflecting mirror holder of the laser scanner shown in FIG. 2. FIG. 3 is a partially enlarged perspective view of a reflecting mirror and a reflecting mirror holder shown in FIG. 2. It is a top view of the reflecting mirror holder shown in FIG. It is a perspective view of the clip of the reflector holder shown in FIG. It is a perspective view of the inclination adjustment apparatus of the reflecting mirror holder shown in FIG. FIG. 6 is a plan view showing a state where the reflecting mirror is held by the reflecting mirror holder shown in FIG. 5. It is the schematic which shows the curve deformation | transformation of the reflective mirror of an initial state. It is a figure which shows the curvature amount of the reflective mirror of an initial state. It is the schematic which shows the curve deformation | transformation of the reflecting mirror after adjustment. It is a figure which shows the curvature amount of the reflecting mirror after adjustment. It is a top view which shows the reflective mirror concerning 2nd embodiment, and a reflective mirror holder. FIG. 14 is a plan view showing a state where the reflecting mirror is held by the reflecting mirror holder shown in FIG. 13. It is the schematic which shows the curve deformation | transformation of the reflective mirror of an initial state. It is a figure which shows the curvature amount of the reflective mirror of an initial state. It is the schematic which shows the curve deformation | transformation of the reflecting mirror after adjustment. It is a figure which shows the curvature amount of the reflecting mirror after adjustment. It is a top view which shows the reflective mirror concerning 3rd embodiment, and a reflective mirror holder. It is a top view which shows the reflective mirror concerning 4th embodiment, and a reflective mirror holder. It is a top view which shows the reflective mirror concerning 5th embodiment, and a reflective mirror holder. It is the schematic which shows the curve deformation | transformation of the reflective mirror of an initial state. It is a top view which shows the conventional reflective mirror and reflective mirror holder. FIG. 24 is a schematic diagram illustrating a curved deformation of the reflecting mirror illustrated in FIG. 23.

Hereinafter, embodiments of the present invention will be described with reference to FIGS.
An image forming apparatus 1 according to an embodiment of the present invention is a tandem full color laser printer. As shown in FIG. 1, the image forming apparatus 1 is provided with a paper feed unit 2, an image forming unit 3, a fixing unit 4, and a paper discharge unit 5 in a housing 6.

  The paper feed unit 2 includes a paper feed cassette 11 that is detachably attached to the housing 6 and mounts paper as a recording medium, and a paper feed roller that feeds the first sheet of the paper in the paper feed cassette 11. 12, and registration rollers 13 and 14 that abut the leading end of the sheet fed from the sheet feeding roller 12 to correct the inclination of the sheet.

  The image forming unit 3 includes a laser scanner 15 as an optical scanning device, and photosensitive drums 16 to 19 as latent image carriers that are scanned by laser beams 71 to 74 as light beams formed by the laser scanner 15. An intermediate transfer belt 27 for transferring the developed images formed on the photosensitive drums 16 to 19 to a sheet, and a driving roller 28 and a driven roller 30 around which the intermediate transfer belt 27 is suspended. .

  On the outer peripheral side of the photosensitive drums 16 to 19 are a charging device that charges the outer peripheral surface (scanned surface) of the photosensitive drums 16 to 19 to a negative charge, and a developing unit that develops the electrostatic latent image with toner. A developing device and a cleaning device for cleaning residual toner are provided. The photosensitive drums 16 to 19 are negatively charged on the outer peripheral surface by the charging device, and an electrostatic latent image is formed by irradiating the charged outer peripheral surfaces with laser beams 71 to 74. The formed latent image is developed with the toner of the developing device.

  The photoconductive drums 16 to 19 are made of an aluminum base tube formed in a cylindrical shape, and an organic photoconductor layer is formed on the outer peripheral surface of the aluminum base tube. The organic photoreceptor layer includes an undercoat layer coated on the outer peripheral surface of the aluminum base tube, a charge generation layer that generates positive charges and negative charges by photoelectric conversion, and positive charges generated in the charge generation layer. It has a charge transport layer that neutralizes negative charges that are transported and charged on the surface, and an overcoat layer that improves durability.

  On the photosensitive drum 16, a latent image is formed on the organic photosensitive layer by a laser beam 71 scanned in response to a yellow (Y) image forming signal, and a developed image is formed by yellow (Y) toner of the developing device. It is formed. On the photosensitive drum 17, a latent image is formed on the organic photosensitive layer by the laser beam 72 scanned in response to the image forming signal of magenta (M), and the developed image is formed by the magenta (M) toner of the developing device. It is formed. On the photosensitive drum 18, a latent image is formed on the organic photosensitive layer by a laser beam 73 scanned in accordance with a cyan (C) image forming signal, and the developed image is formed by cyan (C) toner of the developing device. It is formed. On the photosensitive drum 19, a latent image is formed on the organic photosensitive layer by the laser beam 74 scanned in response to the black (Bk) image forming signal, and the developed image is formed by the black (Bk) toner of the developing device. It is formed.

  The intermediate transfer belt 27 is an endless belt, and is suspended on a driving roller 28 driven by a motor and a driven roller 30. The intermediate transfer belt 27 is rotated in the direction indicated by the arrow A by the rotational driving force of the driving roller 28.

  The intermediate transfer belt 27 sequentially conveys paper onto the upper portions of the photosensitive drums 16 to 19 and is formed on the photosensitive drum 17 and a developed image of yellow (Y) toner formed on the photosensitive drum 16. A developed image of magenta (M) toner, a developed image of cyan (C) toner formed on the photosensitive drum 18, and a developed image of black (Bk) toner formed on the photosensitive drum 19 Are sequentially transferred onto the paper.

  The fixing unit 4 is provided with a fixing roller 31 that applies heat to the toner of each color of the paper on which the developed image is transferred, and a pressure roller 32 that applies pressure to the toner on the paper. The fixing roller 31 is made of an aluminum base tube formed in a thin cylindrical shape. In the fixing roller 31, a silicone rubber layer having a fluororesin film is formed on the outer peripheral surface of the aluminum base tube. The fixing roller 31 is provided with a halogen heater in the aluminum base tube.

  The halogen heater is provided over the entire axial length of the aluminum base tube. The outer peripheral surface of the fixing roller 31 is heated to 160 to 180 ° C. by a halogen heater. The pressure roller 32 is provided with a silicone rubber layer on the outer peripheral surface of an aluminum base tube formed in a cylindrical shape.

  The paper discharge unit 5 is provided with paper discharge rollers 33 and 34 for discharging the paper on which the development images of the respective color toners are fixed by the fixing roller 31 and the pressure roller 32, and paper discharge rollers 33 and 34. And a finisher 35 for stocking the printed paper. The paper discharge rollers 33 and 34 are provided with rubber or synthetic resin rollers on the outer periphery of a metal cylindrical shaft.

  As shown in FIG. 2, the laser scanner 15 according to the present embodiment includes a laser light source that emits laser beams 71 to 74 as light beams and a laser beam 71 to 74 emitted from the laser light source in a housing 41. Are scanned in the main scanning direction (the axial direction of the photosensitive drums 16 to 19) to scan at equal angles, and are scanned at equal angles in the main scanning direction by the polygon mirrors 52 and 53. Fθ lenses 54 to 57 for converting the laser beams 71 to 74 into constant-velocity linear scanning, and the outer peripheral surfaces of the photosensitive drums 16 to 19 with the laser beams 71 to 74 subjected to constant-velocity linear scanning by the fθ lenses 54 to 57. Reflecting mirrors 61 to 68 for reflecting toward the surface are provided.

  The housing 41 includes dustproof glasses 43 to 46 that prevent dust and the like from entering the housing 41 and transmit the laser beams 71 to 74, and a lid 42 that seals the housing 41.

  The laser light source includes a laser diode that emits a laser beam 71 corresponding to a yellow (Y) image formation signal, a laser diode that emits a laser beam 72 corresponding to a magenta (M) image formation signal, and cyan (C). And a laser diode that emits a laser beam 74 corresponding to a black (Bk) image formation signal.

  The laser light source shapes the laser diode, a collimator lens that converts the laser beams 71 to 74 emitted from the laser diode into parallel light beams, and the beam widths of the laser beams 71 to 74 converted into parallel light beams by the collimator lens. A slit and a cylindrical lens that converts the laser beams 71 to 74 whose beam widths have been shaped by the slit into light beams diverging in the main scanning direction and the sub-scanning direction (the circumferential surface direction of the photosensitive drums 16 to 19). Is provided.

  The polygon mirrors 52 and 53 are made of aluminum and formed in a hexagonal prism shape. The polygon mirrors 52 and 53 have six mirror surfaces that reflect the laser beams 71 to 74. The polygon mirrors 52 and 53 are rotated tens of thousands of revolutions per minute by a motor or the like. The polygon mirror 52 scans each of the laser beams 71 and 74 emitted from the laser light source in the main scanning direction. Each of the laser beams 72 and 73 emitted from the laser light source is scanned by the polygon mirror 53 in the main scanning direction.

  The reflecting mirrors 61 to 68 are made of aluminum having a high reflectivity and have a length of 450 millimeters, a width of 20 millimeters, and a thickness of 2 millimeters. Reflectors 61-68 have an effective range of about 300 millimeters used to reflect laser beams 71-74.

  The reflecting mirrors 61 and 62 reflect the laser beam 71 corresponding to the yellow (Y) image forming signal toward the outer peripheral surface of the photosensitive drum 16. The reflecting mirrors 63 and 64 reflect the laser beam 72 corresponding to the image forming signal of magenta (M) toward the outer peripheral surface of the photosensitive drum 17. The reflecting mirrors 65 and 66 reflect the laser beam 73 corresponding to the cyan (C) image forming signal toward the outer peripheral surface of the photosensitive drum 18. The reflecting mirrors 67 and 68 reflect the laser beam 74 corresponding to the black (Bk) image forming signal toward the outer peripheral surface of the photosensitive drum 19.

  As shown in FIG. 3, the reflecting mirror 61 includes a bracket 82 as a reflecting mirror holder for holding the reflecting mirror 61, an inclination adjusting device 83 for adjusting the inclination of the reflecting mirror 61 in the direction indicated by arrow B, and It is held in the housing 41 by a receiving portion 98 that supports the reflecting mirror 61 on the housing 41 and a leaf spring 97 that biases the reflecting mirror 61 toward the receiving portion 98. Similarly to the reflecting mirror 61, the reflecting mirrors 62 to 68 are held in the housing 41 by a bracket 82, an inclination adjusting device 83, a receiving portion 98, and a leaf spring 97.

  As shown in FIG. 3, the bracket 82 includes support claws 84 and 85 that are engaged with the mirror surface of the reflecting mirror 61, clips 95 and 96 as pressing members that press the back surface of the mirror surface of the reflecting mirror 61, A screw member 93 is provided as a pressing member for pressing the mirror surface side of the reflecting mirror 61. As shown in FIG. 4, the bracket 82 includes a main body portion 82a, an upper surface portion 82b that is bent at the upper portion of the main body portion 82a, and a lower surface portion 82c that is bent at the lower portion of the main body portion 82a. The cross section is substantially U-shaped.

  The support claws 84 and 85 are provided at both ends of the bracket 82 as shown in FIG. As shown in FIG. 4, the support claw 84 is formed of a pair of a support claw 84a formed on the upper surface portion 82b and a support claw 84b formed on the lower surface portion 82c. Similarly to the support claw 84, the support claw 85 is formed by a pair of a support claw formed on the upper surface portion 82b and a support claw formed on the lower surface portion 82c.

  As shown in FIG. 3, the clips 95 and 96 are provided at both ends of the bracket 82 and closer to the center of the bracket 82 than the support claws 84 and 85. As shown in FIG. 4, the clips 95 and 96 are sandwiched between the rear surface of the mirror surface of the reflecting mirror 61 and the main body portion 82 a of the bracket 82. The clips 95 and 96 press the back surface of the mirror surface of the reflecting mirror 61 in a direction substantially perpendicular to the mirror surface.

  As shown in FIG. 6, the clips 95 and 96 are bent by a handle portion 95 a attached to the main body portion 82 a of the bracket 82, an engagement hole 95 b that engages with an engagement protrusion provided in the main body portion 82 a, A portion 95c and a pressing portion 95d that presses the back surface of the mirror surface of the reflecting mirror 61 are formed. The clips 95 and 96 are made of a cold-rolled steel strip for springs and are formed by pressing or the like.

  As shown in FIG. 3, the screw member 93 is provided at one end of the bracket 82 and on the center side of the bracket 82 with respect to the support claw 84 and the clip 95. As shown in FIG. 4, the screw member 93 is screwed into a mounting hole 86a (shown in FIG. 5) of a mounting piece 86 extending from the upper surface portion 82b. Therefore, the curved shape of the reflecting mirror 61 of the reflecting bow 61 is adjusted according to the tightening of the screw member 93.

  The screw member 93 is coated with an adhesive as a fixing means at a portion in contact with the reflecting mirror 61. As the adhesive, an ultraviolet curable adhesive mainly composed of an acrylic resin is used. For this reason, after the curvature of the reflecting mirror 61 is corrected by the screw member 93, the screw member 93 is irradiated with ultraviolet rays to the portion where the screw member 93 and the reflecting mirror 61 are in contact with each other. It fixes in the state contact | abutted to 61. FIG. Therefore, the reflecting mirror 61 is stably held in a shape in which the curved shape is corrected by the screw member 93.

  As shown in FIG. 5, the brackets 82 on which the reflecting mirrors 61 to 68, the clips 95 and 96, and the screw members 93 are not held are support claws 84 and 85 that support the mirror surfaces of the reflecting mirrors 61 to 68. The first mounting portions 88 and 89 and the second mounting portions 90 and 91 to which the clips 95 and 96 for supporting the back surface of the mirror surface of the reflecting mirror 61 are supported are provided at both ends.

  The first mounting portions 88 and 89 are provided closer to the center of the bracket 82 than the support claws 84 and 85. The second mounting portions 90 and 91 are provided on both end sides of the bracket 82 with respect to the support claws 84 and 85. As shown in FIG. 4, the second attachment portion 90 is provided with an engagement protrusion 90 a that engages with an engagement hole 95 b formed in the clip 95. Similar to the second mounting portion 90, the first mounting portions 88 and 89 and the second mounting portion 91 are provided with engaging protrusions.

  The bracket 82 has a first attachment piece 86 to which a screw member 93 that pushes the back surface of the reflecting mirrors 61 to 68 is attached, and a second attachment piece 87 to which a screw member 93 that pushes the back surface of the mirror surface of the reflecting mirrors 61 to 68 is attached. Are provided at one end and on the center side of the bracket 82 with respect to the support claw 84 and the first mounting portion 88. The first mounting piece 86 has a mounting hole 86a into which the screw member 93 is screwed. The second attachment piece 87 has an attachment hole 87a into which the screw member 93 is screwed.

  As shown in FIG. 7, the tilt adjusting device 83 is provided with a pulse motor 101 that adjusts the tilt of the reflecting mirrors 61 to 68, and a holder 104 that fixes the pulse motor 101 to the housing 41. The pulse motor 101 includes an adjuster 102 that expands and contracts with rotation of a rotating shaft (not shown), and a connector 103 that is supplied with electric power for driving the pulse motor 101. The adjuster 102 is connected to one end of the reflecting mirrors 61 to 68 via a connecting member 105 (shown in FIG. 3).

  As shown in FIG. 3, the receiving portion 98 has one end fixed to the housing 41 and the other end in contact with the mirror surfaces of the reflecting mirrors 61 to 68. One end of the leaf spring 97 is fixed to the housing 41, and the other end is urged against the back surface of the mirror surface of the reflecting mirrors 61-68. For this reason, the said reflecting mirrors 61-68 are set as a desired inclination by moving one end side to the arrow B direction by using the other end side supported by the said receiving part 98 and the said leaf | plate spring 97 as a fulcrum. be able to.

  In the image forming apparatus 1 configured as described above, the curvature correction of the reflecting mirrors 61 to 68 of the laser scanner 15 is performed when the image forming apparatus 1 is shipped. In the initial state immediately after the assembly of the image forming apparatus 1, as shown in FIG. 8, the reflecting mirror 61 is supported by support claws 84 and 85 of the bracket 82 and clips 95 and 96. The reflecting mirrors 62 to 68 are supported by support claws 84 and 85 and clips 95 and 96 in the same manner as the reflecting mirror 61.

  For this reason, the reflecting mirrors 61 to 68 in the initial state are curved into a substantially U shape as shown by a dotted line, as shown in FIG. The reflecting mirrors 61 to 68 in the initial state have a curvature of about 100 micrometers as shown in FIG. 10 in an effective range of about 300 millimeters for reflecting the laser beams 71 to 74.

  From this initial state, the threaded member 93 is screwed into the mounting hole 86a of the first mounting piece 86 and the mirror surface of the reflecting mirror 61 is pushed in, so that the reflecting mirror 61 is corrected as shown in FIG. Become.

  As shown in FIG. 11, the corrected reflecting mirror 61 is curved and deformed into a shape as indicated by a dotted line. As shown in FIG. 12, the corrected reflecting mirror 61 has a bending amount of about 20 micrometers in the effective range of the mirror surface of about 300 millimeters.

  The mirrors within the effective range of the reflecting mirrors 61 to 68 are adjusted by the tilt adjusting device 83 so as to be substantially parallel to the outer peripheral surfaces of the photosensitive drums 16 to 19, and the curvature correction of the reflected lights 61 to 68 is completed. .

  The bracket 82 that holds the reflecting mirrors 61 to 68 of the laser scanner 15 of the image forming apparatus 1 according to the above-described embodiment includes support claws 84 and 85 that support the mirror surfaces of the reflecting mirrors 61 to 68, and the reflected light 61. Clips 95 and 96 that press and support the rear surfaces of the mirror surfaces of ˜68, and screw members 93 that push in the mirror surfaces of the reflected lights 61 to 68 are provided. The support claws 84 and 85 and the clips 95 and 96 are provided at both ends of the bracket 82. The screw member 93 is provided at one end of the bracket 82.

  For this reason, since the reflected light 61-68 is pushed in the direction opposite to the bending direction of the reflected light 61-68 curved and deformed in a substantially U shape by the screw member 93 provided at one end, the laser beam 71 Mirrors within the effective range used to reflect ~ 74 are flattened. Therefore, the scanning lines of the laser beams 71 to 74 reflected by the reflected lights 61 to 68 are linearized.

  The scanning line of the laser beams 71 to 74 reflected by the reflecting mirrors 61 to 68 is made substantially parallel to the outer peripheral surfaces of the photosensitive drums 16 to 19 by the tilt adjusting device 83. As described above, the scanning lines of the laser beams 71 to 74 are linearized and are substantially parallel to the outer peripheral surfaces of the photosensitive drums 16 to 19, thereby preventing color misregistration in the full-color image forming apparatus.

(Second embodiment)
Next, a second embodiment of the bracket 82 that holds the reflecting mirrors 61 to 68 of the laser scanner 15 of the image forming apparatus 1 according to the present invention will be described with reference to the drawings. In addition, the same code | symbol is attached | subjected to the part same as embodiment mentioned above, and description is abbreviate | omitted.

  As shown in FIG. 13, the reflecting mirror 61 is held by a bracket 82. The reflecting mirror 61 is provided with an inclination adjusting device 83 at one end and a receiving portion 98 and a leaf spring 97 at the other end. The reflecting mirrors 62 to 68 are held by the bracket 82 similarly to the reflecting mirror 61, and are provided with an inclination adjusting device 83, a receiving portion 98, and a leaf spring 97.

  As shown in FIG. 13, the bracket 82 presses and supports the back surface of the mirror surface of the reflecting mirror 61 on the second mounting portions 90 and 91 formed on both ends of the bracket 82 with respect to the support claws 84 and 85. Clips 95 and 96 are provided. The bracket 82 is provided with a screw member 93 that pushes the rear surface of the mirror surface of the reflecting mirror 61 into a second mounting piece 87 formed on the center side of the bracket 82 with respect to the support claw 84.

  The curvature correction of the reflecting mirrors 61 to 68 of the laser scanner 15 is performed at the time of shipment of the image forming apparatus 1. The initial state immediately after the assembly of the image forming apparatus 1 is as shown in FIG. The support claws 84 and 85 of the bracket 82 and the clips 95 and 96 provided at both ends of the bracket 82 are supported. For this reason, the reflecting mirror 61 in the initial state is curved and deformed into a substantially inverted U shape as shown by a dotted line, as shown in FIG. As shown in FIG. 16, the reflecting mirror 61 in the initial state has a bending amount of about 100 micrometers at about 300 millimeters within the effective range of the mirror surface.

  From this initial state, the screw member 93 is screwed into the mounting hole 87a of the second mounting piece 87, whereby the reflecting mirror 61 is corrected as shown in FIG. As shown in FIG. 17, the corrected reflecting mirror 61 is curved and deformed into a shape as indicated by a dotted line. As shown in FIG. 18, the corrected reflecting mirror 61 has a bending amount of about 20 micrometers at about 300 millimeters within the effective range of the mirror surface.

  The mirror surface within the effective range of the reflecting mirrors 61 to 68 is adjusted by the tilt adjusting device 83 so as to be substantially parallel to the outer peripheral surface of the photosensitive drums 16 to 19, and the curvature correction of the reflecting mirrors 61 to 68 is completed.

  The bracket 82 that holds the reflecting mirrors 61 to 68 of the laser scanner 15 of the image forming apparatus 1 according to the second embodiment described above includes support claws 84 and 85 that support the mirror surfaces of the reflecting mirrors 61 to 68, and the reflection. Clips 95 and 96 that press and support the back side of the mirror surface of the mirrors 61 to 68, and a screw member 93 that presses the back side of the mirror surface of the reflecting mirrors 61 to 68 are provided. The support claws 84 and 85 and the clips 95 and 96 are provided at both ends of the bracket 82. The screw member 93 is provided at one end of the bracket 82.

  For this reason, since the reflecting mirrors 61 to 68 are pushed in a direction opposite to the bending direction of the reflecting mirrors 61 to 68 that are curved and deformed in a substantially inverted U shape by the screw member 93 provided at one end, the laser beams 71 to 68 are pushed. The mirror surface within the effective range reflecting 74 is relatively flat. Therefore, the scanning lines of the laser beams 71 to 74 reflected by the reflecting mirrors 61 to 68 are linearized.

  Further, the tilt adjusting device 83 adjusts the mirror surfaces within the effective range of the reflecting mirrors 61 to 68 so as to be substantially parallel to the outer peripheral surfaces of the photosensitive drums 16 to 19. As described above, the scanning lines of the laser beams 71 to 74 are linearized and are substantially parallel to the outer peripheral surfaces of the photosensitive drums 16 to 19, thereby preventing color misregistration in the full-color image forming apparatus.

(Third embodiment)
Next, a third embodiment of the bracket 82 that holds the reflecting mirrors 61 to 68 of the laser scanner 15 of the image forming apparatus 1 according to the present invention will be described with reference to the drawings. In addition, the same code | symbol is attached | subjected to the part same as embodiment mentioned above, and description is abbreviate | omitted.

  The reflecting mirror 61 is held by a bracket 82A as shown in FIG. The reflecting mirror 61 is provided with an inclination adjusting device 83 at one end and a receiving portion 98 and a leaf spring 97 at the other end. Like the reflection mirror 61, the reflection mirrors 62 to 68 are held by a bracket 82A, and are provided with an inclination adjusting device 83, a receiving portion 98, and a leaf spring 97.

  The bracket 82A includes support claws 84 and 85 provided on both ends of the bracket 82A, first mounting portions 88 and 89 provided on the center side of the bracket 82A with respect to the support claws 84 and 85, and the support Second mounting portions 90 and 91 provided on both ends of the bracket 82A with respect to the claws 84 and 85, and a front mounting piece 92 and a rear mounting provided on the center side of the bracket 82A with respect to the support claws 84 and 85. Pieces 94 and 99 are provided.

  The reflecting mirror 61 is supported by support claws 84 and 85 provided on both ends of the bracket 82A, and clips 95 and 96 provided on the second mounting portions 90 and 91, respectively. The reflecting mirror 61 is pushed in a direction facing the reverse U-shaped bending direction of the reflecting mirror 61 by a screw member 93 provided on the rear mounting piece 94. When the clips 95 and 96 are provided on the first attachment portions 88 and 89, the screw member 93 is provided on the front attachment piece 92.

  The front mounting piece 92 and the rear mounting pieces 94 and 99 are, with respect to the total length L of the reflecting mirror 61, start from one end of the reflecting mirror 61, in a range of 1 / 4L <1 / 2L, and 1 / 2L < It is provided in the range of 3 / 4L.

  This range is that in the reflecting mirror 61 having the natural frequency λ, the length from one end of the reflecting mirror 61 to the rear mounting piece 94 and the length from the other end of the reflecting mirror 61 to the rear mounting piece 94 are: The length is not an integral multiple of λ / 2. For this reason, a resonance phenomenon in which the natural vibration having the node of one end of the reflecting mirror 61 and the rear mounting piece 94 and the natural vibration having the node of the other end of the reflecting mirror 61 and the rear mounting piece 94 reinforce each other. Is prevented.

  In the bracket 82A that holds the reflecting mirrors 61 to 68 of the laser scanner 15 of the image forming apparatus 1 according to the third embodiment described above, the screw member 93 with respect to the total length L of the reflecting mirrors 61 to 68 is 1 / 4L <. It is provided in the range of 1 / 2L or in the range of 1 / 2L <3 / 4L.

  For this reason, the length from one end of the reflecting mirrors 61 to 68 to the screw member 93 and the length from one end of the reflecting mirrors 61 to 68 to the screw member 93 are not integral multiples of λ / 2. Therefore, the resonance in which the natural vibration having the node of one end of the reflecting mirrors 61 to 68 and the screw member 93 and the natural vibration having the node of the screw member 93 from the other end of the reflecting mirrors 61 to 68 reinforce each other. The phenomenon is prevented.

  Therefore, the occurrence of defects such as banding caused by the resonance of the reflecting mirrors 61 to 68 is prevented. As a result, defects such as color misregistration and banding in the full-color image forming apparatus are prevented.

(Fourth embodiment)
Next, a fourth embodiment of the bracket 82 that holds the reflecting mirrors 61 to 68 of the laser scanner 15 of the image forming apparatus 1 according to the present invention will be described with reference to the drawings. In addition, the same code | symbol is attached | subjected to the part same as embodiment mentioned above, and description is abbreviate | omitted.

  As shown in FIG. 20, the reflecting mirror 61 is held by a bracket 82B. The reflecting mirror 61 is provided with an inclination adjusting device 83 at one end and a receiving portion 98 and a leaf spring 97 at the other end. Similarly to the reflecting mirror 61, the reflecting mirrors 62 to 68 are held by a bracket 82B, and are provided with an inclination adjusting device 83, a receiving portion 98, and a leaf spring 97.

  The bracket 82B includes support claws 84 and 85 provided at both ends of the bracket 82B, first mounting portions 88 and 89 provided closer to the center of the bracket 82B than the support claws 84 and 85, and the support Second mounting portions 90 and 91 provided on both ends of the bracket 82B with respect to the claws 84 and 85, and a first mounting piece 86 and a first mounting piece 86 provided on the center side of the bracket 82B with respect to the support claws 84 and 85. Two attachment pieces 87, a first vibration isolation attachment piece 111, and a second vibration isolation attachment piece 112 are provided.

  The reflecting mirror 61 is supported by support claws 84 and 85 provided at both ends of the bracket 82B and clips 95 and 96 attached to the second attachment portions 90 and 91. The reflecting mirror 61 includes a screw member 93 provided on the second attachment piece 87, a screw member 113 provided on the first vibration isolation attachment piece 111, and a screw member 114 provided on the second vibration isolation attachment piece 112. Are pushed in a direction opposite to the inverted U-shaped bending direction of the reflecting mirror.

  The bracket 82B that holds the reflecting mirrors 61 to 68 of the laser scanner 15 of the image forming apparatus 1 according to the above-described fourth embodiment has the bracket 82B more than the support claws 84 and 85 provided at both ends of the bracket 82B. A first attachment piece 86, a second attachment piece 87, a first vibration isolation attachment piece 111, and a second vibration isolation attachment piece 112 provided on the center side are provided.

  For this reason, the reflecting mirrors 61 to 68 are pushed into a plurality of places by the plurality of screw members 93. Therefore, the curved deformation of the reflecting mirrors 61 to 68 can be finely adjusted. Moreover, since the reflective mirrors 61-68 have a plurality of nodes formed by the plurality of screw members 93, the natural frequency of the reflective mirrors 61-68 further increases.

  Therefore, the occurrence of defects such as banding caused by the vibration of the reflecting mirrors 61 to 68 is prevented. As a result, color misregistration, banding and the like in the full color image forming apparatus are prevented.

(Fifth embodiment)
Next, the brackets 82 that respectively hold the first reflecting mirror 61 and the second reflecting mirror 62 of the laser scanner 15 of the image forming apparatus 1 according to the present invention will be described with reference to the drawings. In addition, the same code | symbol is attached | subjected to the part same as embodiment mentioned above, and description is abbreviate | omitted.

  As shown in FIG. 21, a first reflecting mirror 61 that reflects a laser beam 71 scanned in the main scanning direction, and the laser beam 71 reflected by the first reflecting mirror 61 is directed toward the outer peripheral surface of the photosensitive drum 16. The second reflecting mirror 62 to be reflected is held by the bracket 82.

  The first reflecting mirror 61 is provided with an inclination adjusting device 83 at one end and a receiving portion 98 and a leaf spring 97 at the other end, and is held in the housing 41. The other first reflecting mirrors 63, 65, and 67 are held by the bracket 82 </ b> B similarly to the first reflecting mirror 61, and are provided with an inclination adjusting device 83, a receiving portion 98, and a leaf spring 97, It is held in the housing 41.

  The second reflecting mirror 62 is fixed to the housing 41 of the laser scanner 15 via a support member (not shown). The other second reflecting mirrors 64, 66, 68 are fixed to the housing 41 via a support member, similarly to the second reflecting mirror 62.

  The bracket 82 includes support claws 84 and 85 provided on both ends of the bracket 82, first mounting portions 88 and 89 provided on the center side of the bracket 82 with respect to the support claws 84 and 85, and the support. Second mounting portions 90 and 91 provided on both end sides of the bracket 82 with respect to the claws 84 and 85; and a first mounting piece 86 provided on one end portion on the center side of the bracket 82 with respect to the support claws 84; A second mounting piece 87.

  The first reflecting mirror 61 is supported by support claws 84 and 85 of the bracket 82 and clips 95 and 96 attached to the first attachment portions 88 and 89. The first reflecting mirror 61 is pushed by a screw member 93 provided on the first mounting piece 86 in a direction opposite to the bending direction curved in a substantially U shape.

  The second reflecting mirror 62 is supported by support claws 84 and 85 of the bracket 82 and clips 95 and 96 attached to the second attachment portions 90 and 91. The second reflecting mirror 62 is pushed by a screw member 93 provided on the second mounting piece 87 in a direction opposite to the bending direction curved in a substantially U shape.

  In the image forming apparatus 1 configured as described above, the curvature correction of the reflecting mirrors 61 to 68 of the laser scanner 15 is performed when the image forming apparatus 1 is shipped. As shown in FIG. 22, the first reflecting mirror 61 and the second reflecting mirror 62 in the initial state immediately after the assembly of the image forming apparatus 1 are curved into a substantially U shape as shown by a dotted line.

  From this initial state, the screw member 93 is screwed onto the first mounting piece 86 of the bracket 82 that holds the first reflecting mirror 61, and the screw member 93 is locked to the second mounting piece 87 of the bracket 82 that holds the second reflecting mirror 62. As shown in FIG. 21, the first reflecting mirror 61 and the second reflecting mirror 62 are corrected.

  The first reflecting mirror 61 and the second reflecting mirror 62 in the corrected state are curved and deformed into a shape as indicated by a dotted line as shown in FIG.

  The tilt adjusting device 83 adjusts the mirror surface within the effective range of the first reflecting mirror 61 so as to be substantially parallel to the photosensitive drum 16 or the second reflecting mirror 62, so that the first reflected light 61 and the second reflecting mirror are adjusted. The curvature correction with 62 is completed.

  The bracket 82 that holds the first reflecting mirrors 61, 63, 65, 67 and the second reflecting mirrors 62, 64, 66, 68 of the laser scanner 15 of the image forming apparatus 1 according to the fifth embodiment described above is reflective. Support claws 84 and 85 for supporting the mirror surfaces of the mirrors 61 to 68, clips 95 and 96 for supporting the back surfaces of the mirrors 61 to 68 by pressing, and mirror surfaces of the reflectors 61 to 68 or And a screw member 93 for pushing the back side. The support claws 84 and 85 and the clips 95 and 96 are provided at both ends of the bracket 82. The screw member 93 is provided at one end of the bracket 82.

  Therefore, the bending direction of the initial state of the first reflecting mirror 61 and the bending direction of the initial state of the second reflecting mirror 62 are the same as shown in FIG.

  Therefore, the scanning lines of the laser beams 71 to 74 are matched between the first reflecting mirror 61 and the second reflecting mirror 62, and deformation of the scanning lines is prevented. As a result, color misregistration, banding and the like in the full color image forming apparatus are prevented.

  In addition, embodiment mentioned above only showed the typical form of this invention, and this invention is not limited to embodiment. That is, various modifications can be made without departing from the scope of the present invention.

1 Image forming device 52, 53 Polygon mirror 61, 63, 65, 67 First reflecting mirror 62, 64, 66, 68 Second reflecting mirror 71, 72, 73, 74 Laser beam 82 Bracket 83 Tilt adjusting device 84, 85 Claw 86 First mounting piece 87 Second mounting piece 88, 89 First mounting portion 90, 91 Second mounting portion 93 Screw member 95, 96 Clip

JP 2009-145495 A

Claims (10)

A light source that emits a light beam, a scanning unit that deflects the light beam emitted from the light source in the main scanning direction and that scans in the main scanning direction, and is deflected in the main scanning direction in the main scanning direction by the scanning unit. A reflector for reflecting the light beam scanned in the main scanning direction, and a reflector holder for holding the reflector in the optical scanning device,
(A) The reflecting mirror holder includes a supporting member for supporting the mirror surface side of the reflecting mirror, a pressing member for pressing and supporting the back surface side of the mirror surface of the reflecting mirror, and the mirror surface side or the back surface of the reflecting mirror. A pushing member for pushing the side, and
(B) the support member and the pressing member are respectively provided at both ends of the reflector holder; and
(C) The pushing member is provided at one end of the reflecting mirror holder. A reflecting mirror holder.   The reflecting mirror holder according to claim 1, wherein the reflecting mirror holder is provided with adjusting means for adjusting a reflection direction of the light beam by adjusting an inclination of the reflecting mirror.   The reflector holder according to claim 1 or 2, wherein the pushing member is provided closer to the center of the reflector holder than the support member.   The said pressing member is provided in the center side of the said reflector holding tool rather than the said supporting member, or the edge part side of the said reflecting mirror holder rather than the said supporting member, The Claims 1-3 characterized by the above-mentioned. The reflecting mirror holder according to any one of the above.   The said pushing member is provided in the range of 1 / 4L <1 / 2L with respect to the full length L of the said reflective mirror, or 1 / 2L <3 / 4L. Item 5. The reflector holder according to any one of items 4 to 5.   The said pushing member is provided with two or more in the said reflecting mirror holder, The reflecting mirror holder as described in any one of Claims 1-5 characterized by the above-mentioned.   The said pressing member is being fixed by the fixing means, The reflecting mirror holder as described in any one of Claims 1-6 characterized by the above-mentioned.   8. The reflector holder according to claim 7, wherein the fixing means is a photo-curing adhesive. A light source that emits a light beam, a scanning unit that deflects the light beam emitted from the light source in the main scanning direction and that scans in the main scanning direction, and is deflected in the main scanning direction in the main scanning direction by the scanning unit. A reflecting mirror that reflects a light beam scanned in the main scanning direction;
An optical scanning device, wherein the reflecting mirror is held by the reflecting mirror holder according to any one of claims 1 to 8.   10. The optical scanning device according to claim 9, a latent image carrier on which a latent image is formed by a light beam emitted from the optical scanning device, and developing means for developing the latent image formed on the latent image carrier. And an image forming apparatus.

Images