JP5455085B2 - Optical scanning apparatus and image forming apparatus - Google Patents

Description

  The present invention relates to an optical scanning device and an image forming apparatus.

  2. Description of the Related Art Conventionally, in an image forming apparatus such as a laser beam printer, a digital copying machine, or a laser facsimile, a latent image carrier such as a photosensitive member is optically scanned with a light beam generated on the basis of image information. What forms a latent image is known. In general, an optical scanning device in such an image forming apparatus includes a light source such as a laser diode, scanning means including a polygon mirror, an fθ lens, a reflecting mirror, and the like. Then, the light beam emitted from the light source is guided to the surface of the latent image carrier by reflection by the reflecting mirror while being scanned in the main scanning direction by the scanning unit or condensed by the fθ lens.

  In the optical scanning apparatus having such a configuration, subtle distortions due to processing errors during manufacturing are inevitably generated in the optical system components and the support constituting the optical scanning apparatus. In addition, there are not a few assembly errors in optical system parts and supports. The main scanning line on the surface of the latent image carrier may be bent or tilted due to these distortions, assembly errors, and the like. When such a curve or inclination occurs, a normal image cannot be formed.

  In view of this, the present applicant has proposed an optical scanning apparatus in Patent Document 1 provided with a curvature correction mechanism as a correction means that can correct a main scanning line that is curved in any direction. This bending correction mechanism holds the reflecting mirror in a state where it is forcedly bent in the thickness direction by the holder. Then, the reflecting mirror held in this way is pushed in by an adjusting screw as an adjusting member, thereby applying a bending force in a direction opposite to the forced bending direction by the holder to the reflecting mirror. When the reflecting mirror is slightly pushed in by this adjusting screw, the amount of bending of the reflecting mirror that is forcibly bent by the holder decreases. Further, when the reflecting mirror is further pushed in, the reflecting mirror curves in the opposite direction to the initial state. In this way, the bending of the main scanning line is corrected by canceling the bending of the main scanning line with the bending of the reflecting mirror in the reverse direction by the bending correction mechanism capable of bending the reflecting mirror in any direction. Can do.

  An optical scanning apparatus provided with an inclination correction mechanism as correction means capable of correcting the inclination of the main scanning line is also generally known. This tilt correction mechanism supports one end side of the reflecting mirror with an adjusting screw. When the adjustment screw is rotated to raise or lower the adjustment screw, the adjustment screw side end of the reflecting mirror is raised or lowered. As a result, the reflecting mirror rotates with the end on the side opposite to the end on the adjustment screw side as a fulcrum, the posture thereof changes, and the inclination of the main scanning line can be corrected.

In the optical scanning device, the bending correction and the inclination correction of the main scanning line are generally performed as follows.
The optical scanning device is mounted on the mounting table of the adjusting device that adjusts the inclination or bending of the scanning line in the same posture as when mounted on the image forming apparatus. Then, when the optical scanning device is mounted on the image forming apparatus, a photo detector such as a CCD is provided at a position corresponding to a position where the surface of the photoconductor to be irradiated with light is to be positioned with respect to the optical scanning device. Deploy. One or more light receivers are arranged at arbitrary points in the direction corresponding to the photosensitive member axial direction. Thereafter, the optical scanning device is driven, and scanning light scanned along the direction corresponding to the photosensitive member axial direction is detected by the light receiver. An operator inserts an adjustment jig for applying a rotational force to the adjustment screw such as a driver from an adjustment hole provided in the housing of the optical scanning apparatus, and causes the adjustment jig to access the adjustment screw in the housing. Then, while adjusting the adjustment jig displayed while viewing the adjustment information displayed on the display or the like based on the detection result detected by the light receiver, the bending correction and the inclination correction of the main scanning line are performed.

  However, when the adjustment jig is inserted into the adjustment hole, the adjustment hole is closed by the adjustment jig, and thus the position of the adjustment screw cannot be visually confirmed from the adjustment hole. For this reason, it becomes difficult to access the adjustment screw with the adjustment jig, and it takes time until the adjustment jig has access to the adjustment screw, resulting in problems such as poor scan line bending correction and tilt correction workability. End up.

Therefore, it is conceivable to enlarge the adjustment hole so that the position of the adjustment screw can be visually confirmed even when the adjustment jig is inserted.
However, if the head of the adjustment screw faces down due to the layout of the device, the adjustment jig is accessed from the adjustment hole provided on the lower surface of the housing, and the adjustment work is performed in such a way that the adjustment hole is looked into from below. Otherwise, the adjustment jig cannot access the adjustment screw while visually checking the position of the adjustment screw. Therefore, there is a problem that the workability of scanning line bending correction and tilt correction is poor.

  The present invention has been made in view of the above problems, and an object of the present invention is to provide an optical writing apparatus and an image forming apparatus that can easily perform an operation of correcting the inclination or bending of a scanning line.

In order to achieve the above object, the invention of claim 1 is directed to a light source, a scanning means for irradiating the light irradiation target with the light irradiated from the light source and scanning the light, and light from the light source to the light irradiation target. Optical scanning comprising: an optical element provided on a road; a correction unit that corrects an inclination or a curve of a scanning line by adjusting a posture or a shape of the optical element; and a housing that houses the optical element and the correction unit. In the apparatus, the correction means includes a contact portion that contacts the optical element, and an engagement portion that engages with an adjustment jig inserted from an adjustment hole provided in the housing, and the adjustment jig The contact position of the contact portion with the optical element is displaced by applying a force from, and includes an adjustment member that adjusts the posture or shape of the optical element, and the optical element includes a planar portion, The contact portion is With respect to the normal direction of Jo portion is configured to move in a direction inclined, provided the engagement guide for guiding the adjustment jig is inserted from the adjusting hole with the engaging portion of the adjusting member The engagement guide guides the adjustment jig in the inclined direction between the adjustment hole and the engagement portion .
According to a second aspect of the present invention, in the optical scanning device according to the first aspect, the engagement guide extends from the adjustment hole toward the adjustment member.
According to a third aspect of the present invention , in the optical scanning device according to the first or second aspect , the adjustment hole has an opening guide that guides the adjustment jig toward the adjustment hole. It is.
According to a fourth aspect of the present invention, there is provided the optical scanning device according to any one of the first to third aspects, further comprising a mortar-shaped second engagement guide provided on the adjustment member and having a diameter that decreases toward the engagement portion. it is characterized in that the.
According to a fifth aspect of the present invention, in the optical scanning device according to any one of the first to fourth aspects, the engaging portion is a hexagonal hole.
According to a sixth aspect of the present invention, in the optical scanning device according to the fifth aspect, the adjustment member has a threaded portion, and the outer diameter of the portion of the adjustment member where the hexagonal hole is formed, The outer diameter of the screw portion is larger.
The invention of claim 7, in any one of the optical scanning device 請 Motomeko 1 to 6, characterized in that said optical element is a lens or mirror.
The invention according to claim 8 is characterized in that the optical scanning device according to any one of claims 1 to 7 is mounted.

  In the first to ninth aspects of the invention, when the adjustment jig is engaged with the engagement portion of the adjustment member, the adjustment jig is guided to the engagement portion of the adjustment member by the guide. Even if it is not possible to confirm, the adjustment jig can be easily engaged with the engagement portion of the adjustment member. As a result, the optical scanning line correction operation can be easily performed.

1 is a schematic configuration diagram illustrating a printer according to an embodiment. FIG. 2 is a schematic configuration diagram illustrating an image forming station for Y in the printer. FIG. 2 is a schematic configuration diagram showing an optical writing unit in the printer together with four photosensitive members. The perspective view which shows the 2nd reflective mirror for Y of the same optical writing unit, and its surrounding structure from the mirror surface side of a 2nd reflective mirror. The block diagram which shows the longitudinal cross-section of the 2nd reflective mirror, and its surrounding structure. The block diagram which shows the upper surface of the said 2nd reflective mirror, and its surrounding structure. The block diagram which shows the cross section of the longitudinal direction center part vicinity of the said 2nd reflective mirror, and surrounding structure. The perspective view which shows the longitudinal direction center part vicinity of the 2nd reflective mirror, and its surrounding structure from the back surface side of a 2nd reflective mirror. The schematic diagram explaining the forced bending of the said 2nd reflective mirror. The perspective view which looked at the adjustment screw from the contact part side. The perspective view which looked at the adjustment screw from the engagement part side. The fragmentary sectional view of an adjustment screw. The schematic diagram which shows the 2nd reflective mirror of the state by which a forced curve is corrected by the pushing means of a curvature adjustment mechanism. FIG. 3 is an explanatory diagram showing a configuration when the same optical writing unit in a state of being held on the mounting table of the adjusting device is viewed from the photosensitive member axial direction. The perspective view which shows the example which provided the guide in the adjustment hole of the housing. The schematic sectional drawing which shows the example which provided the guide in the housing adjustment hole 49C. The schematic perspective view which shows the example which provided the guide in the polygon cover. The schematic block diagram which shows the example which provided the guide in the polygon cover. FIG. 3 is a schematic configuration diagram showing an optical writing unit including a scanning lens that condenses light in a sub-scanning direction and a scanning lens that condenses light in a main scanning line direction together with four photosensitive members. The schematic block diagram of the curvature correction | amendment mechanism which correct | amends the curvature of a scanning line with a long lens. The schematic block diagram of the inclination correction mechanism which correct | amends the inclination of a scanning line with a long lens.

Hereinafter, an embodiment in which the present invention is applied to an electrophotographic color laser printer (hereinafter simply referred to as a printer) will be described.
FIG. 1 is a schematic configuration diagram illustrating a printer according to the present embodiment. The printer includes a housing 1 and a paper feed cassette 2 that can be pulled out from the housing 1. Image forming stations 3Y, 3C, and 3C for forming toner images (visible images) of each color of yellow (Y), cyan (C), magenta (M), and black (K) are provided at the center of the housing 1. 3M, 3K. Hereinafter, the subscripts Y, C, M, and K of the respective symbols indicate members for yellow, cyan, magenta, and black, respectively.

FIG. 2 is a schematic configuration diagram showing an image forming station for yellow (Y). The other image forming stations have the same configuration.
As shown in FIGS. 1 and 2, the image forming stations 3Y, 3C, 3M, and 3K include drum-shaped photoconductors 10Y, 10C, 10M, and 10K as latent image carriers that rotate in the direction of arrow A in the drawing. ing. Each of the photoreceptors 10Y, 10C, 10M, and 10K includes an aluminum cylindrical substrate having a diameter of 40 [mm] and an OPC (organic photo semiconductor) photosensitive layer that covers the surface of the photoreceptor. Each of the image forming stations 3Y, 3C, 3M, and 3K includes charging devices 11Y, 11C, 11M, and 11K that charge the photoconductors around the photoconductors 10Y, 10C, 10M, and 10K, respectively. Further, developing devices 12Y, 12C, 12M, and 12K as developing means for developing the latent image formed on the photosensitive member, and cleaning devices 13Y, 13C, 13M, and 13K for cleaning residual toner on the photosensitive member are also provided around the photosensitive member. In preparation.

  Below each of the image forming stations 3Y, 3C, 3M, and 3K, there is provided an optical writing unit 4 as an optical scanning device that performs optical scanning with the writing light L on the photoreceptors 10Y, 10C, 10M, and 10K. Yes. Further, an intermediate transfer unit 5 including an intermediate transfer belt 20 to which toner images formed by the image forming stations 3Y, 3C, 3M, and 3K are transferred above the image forming stations 3Y, 3C, 3M, and 3K. It has. Further, a fixing unit 6 is provided for fixing the toner image transferred to the intermediate transfer belt 20 onto a recording paper P as a transfer member. In addition, toner bottles 7Y, 7C, 7M, and 7K that contain toner of each color of yellow (Y), cyan (C), magenta (M), and black (K) are loaded on the top of the casing 1. . The toner bottles 7 </ b> Y, 7 </ b> C, 7 </ b> M, and 7 </ b> K can be detached from the housing 1 by opening a paper discharge tray 8 formed on the top of the housing 1.

  The optical writing unit 4 as an optical scanning device has a laser diode as a light source, and writing light L as a light beam is directed from this laser diode toward a polygon mirror having a regular polygonal column structure that is rotationally driven. Fire. The emitted writing light L is reflected while being deflected in the main scanning direction by the mirror surface of the rotating polygon mirror. Then, after being folded by a plurality of reflecting mirrors, the peripheral surfaces of the photoreceptors 10Y, 10C, 10M, and 10K that are uniformly charged by the charging devices 11Y, 11C, 11M, and 11K are scanned. Thereby, electrostatic latent images for Y, C, M, and K are formed on the peripheral surfaces of the photoreceptors 10Y, 10C, 10M, and 10K as latent image carriers. The detailed description of the optical writing unit 4 will be described later.

  The intermediate transfer belt 20 of the intermediate transfer unit 5 serving as transfer means is driven to rotate counterclockwise in the figure at a predetermined timing while being wound around a drive roller 21, a tension roller 22 and a driven roller 23. In addition, the intermediate transfer unit 5 includes primary transfer rollers 24Y, 24C, 24M, and 24K that primarily transfer the toner images formed on the photoreceptors 10Y, 10C, 10M, and 10K to the intermediate transfer belt 20. Further, a secondary transfer roller 25 that transfers the toner image primarily transferred onto the intermediate transfer belt 20 to the recording paper P, and a belt that cleans residual toner on the intermediate transfer belt 20 that has not been transferred onto the recording paper P. A cleaning device 26 is also provided.

Next, a process for obtaining a color image in this printer will be described.
First, in the image forming stations 3Y, 3C, 3M, and 3K, the photoreceptors 10Y, 10C, 10M, and 10K are uniformly charged by the charging devices 11Y, 11C, 11M, and 11K. Thereafter, scanning exposure is performed with the writing light L generated based on the image information, and electrostatic latent images are formed on the surfaces of the photoreceptors 10Y, 10C, 10M, and 10K. These electrostatic latent images are developed with toners of the respective colors carried on the developing rollers 15Y, 15C, 15M, and 15K of the developing devices 12Y, 12C, 12M, and 12K, and are converted into Y, C, M, and K toner images. Become. The Y, C, M, and K toner images on the photoreceptors 10Y, 10C, 10M, and 10K are formed on the intermediate transfer belt 20 that is rotated counterclockwise by the action of the primary transfer rollers 24Y, 24C, 24M, and 24K. The primary transfer is carried out in order. The image forming operation of each color at this time is shifted in timing from the upstream side in the moving direction of the intermediate transfer belt 20 toward the downstream side so that the toner image is transferred to the same position on the intermediate transfer belt 20. Executed.

  The surfaces of the photoconductors 10Y, 10C, 10M, and 10K after the completion of the primary transfer are cleaned by the cleaning blades 13a of the cleaning devices 13Y, 13C, 13M, and 13K to prepare for the next image formation.

  The toner filled in the toner bottles 7Y, 7C, 7M, and 7K is placed in the developing devices 12Y, 12C, 12M, and 12K of the image forming stations 3Y, 3C, 3M, and 3K by a conveyance path (not shown) as necessary. A fixed amount is supplied.

  On the other hand, the recording paper P in the paper feed cassette 2 is transported into the housing 1 by a paper feed roller 27 disposed in the vicinity of the paper feed cassette 2 and is secondary by a registration roller pair 28 at a predetermined timing. It is conveyed to the transfer unit. Then, the toner image formed on the intermediate transfer belt 20 is transferred to the recording paper P in the secondary transfer portion. The recording paper P onto which the toner image has been transferred passes through the fixing unit 6 to fix the toner image, and is then discharged to the paper discharge tray 8 by the discharge roller 29. Similar to the photoconductor 10, the transfer residual toner remaining on the intermediate transfer belt 20 is cleaned by a belt cleaning device 26 that contacts the intermediate transfer belt 20.

Next, the configuration of the optical writing unit 4 will be described.
FIG. 3 is a schematic configuration diagram showing the optical writing unit 4 in the printer according to this embodiment together with four photosensitive members. The optical writing unit 4 includes a polygon scanner (not shown) serving as a scanning unit having two polygon mirrors 41a and 41b having a regular polygonal column shape and a polygon motor (not shown) that rotates the polygon mirrors 41a and 41b. It has. These polygon mirrors 41a and 41b have reflecting mirrors on their six side surfaces, and are connected in the vertical direction so that the centers of the regular polygonal columns overlap each other. And it rotates at high speed on the same axis of rotation by a polygon motor (not shown). Thus, when the writing light (laser light) from the laser diode (light beam emitting means) is incident on the side surface, the writing light is deflected and scanned. The polygon mirror 41a deflects the C and M writing lights Lc and Lm traveling from opposite directions to the main scanning direction. The polygon mirror 41b deflects Y and K writing lights Ly and Lk traveling in opposite directions to the main scanning direction.

  In the illustrated optical writing unit 4, deflecting means for deflecting the writing light L as a light beam is configured by polygon mirrors 41 a and 41 b, a polygon motor (not shown), and the like. The optical writing unit 4 includes four deflecting optical systems, soundproof glasses 42a and 42b, scanning lenses 43a and 43b, dustproof glasses 48Y, 48C, 48M, and 48K in addition to the deflecting means.

  The polygon motor and the polygon mirrors 41a and 41b are covered with a polygon cover 46 for soundproofing. For the purpose of allowing the writing light to pass inside and outside the polygon cover 46, the polygon cover 46 is provided with soundproof glasses 42a and 42b. Writing light as a light beam can pass through the inside and outside of the polygon cover 46 by passing through the soundproof glasses 42a and 42b. The soundproof glass 42a is for transmitting the Y and C writing lights Ly and Lc. The soundproof glass 42b is for transmitting the M and K writing lights Lm and Lk.

  The Y and C writing lights Ly and Lc transmitted through the soundproof glass 42a while being deflected in the main scanning direction by the polygon mirror pass through the scanning lens 43a while being aligned in the vertical direction. The scanning lens 43a condenses the writing lights Ly and Lc in the main scanning line direction and the sub-scanning line direction, thereby changing the equiangular motion in the main scanning direction by the polygon mirror to constant velocity linear motion, and the polygon mirror It plays a role of correcting the trouble of falling. The M and K writing lights Lm and Lk that have passed through the soundproof glass 42b pass through the scanning lens 43b located on the opposite side of the scanning lens 43a through the polygon cover.

  The four reflecting optical systems in the optical writing unit 4 are each composed of the above-described laser diode, reflecting mirror, and the like. More specifically, of the colors Y, C, M, and K, taking a Y reflecting optical system as an example, this includes a Y laser diode (not shown), a first reflecting mirror 44Y, and a second reflecting mirror 45Y. Etc. None of these reflecting mirrors has a lens function. Similarly, the reflective optical systems for C, M, and K include a laser diode, a first reflecting mirror (44C to K), and a second reflecting mirror (45C to K).

  The Y, C, M, and K writing lights Ly, Lc, Lm, and Lk that have passed through the scanning lenses 43a and 43b travel toward the reflecting mirrors of the Y, C, M, and K reflecting optical systems. For example, the writing light Ly for Y transmitted through the scanning lens 43a is reflected twice by sequentially reflecting the mirror surfaces of the first reflecting mirror 44Y and the second reflecting mirror 45Y, whereby the Y photoconductor 10Y. Guided to the surface. Similarly, the laser beams Lc, Lm, and Lk for C, M, and K are respectively folded back by two dedicated reflecting mirrors, and are guided to the surfaces of the C, M, and K photoconductors 10C, M, and K. To go. The Y, C, M, and K writing lights Ly, Lc, Lm, and Lk reflected by the mirror surfaces of the second reflecting mirrors Y, C, M, and K were provided on the upper surface of the optical writing unit 4. After passing through the dustproof glasses 48Y, 48C, 48M, and 48K, the light reaches the surfaces of the photoconductors 10Y, 10M, 10C, and 10K.

Next, a characteristic configuration of the printer will be described.
The optical writing unit 4 of this printer corrects the bending direction and the amount of bending of the main scanning line by adjusting the bending state of any one of the reflecting mirrors in the Y, C, M, and K reflecting optical systems. A curvature correcting mechanism as correcting means for correcting the inclination of the main scanning line by adjusting the inclination of the reflecting mirror is provided. Hereinafter, the curvature correction mechanism and the tilt correction mechanism will be described by taking the Y reflection optical system as an example.

  FIG. 4 is a perspective view showing the second reflecting mirror 45Y for Y and the surrounding configuration from the mirror surface side of the second reflecting mirror 45Y. FIG. 5 is a configuration diagram showing a longitudinal section of the second reflecting mirror 45Y for Y and the surrounding configuration. FIG. 6 is a configuration diagram showing the upper surface of the second reflecting mirror 45Y for Y and the surrounding configuration. In these drawings, the second reflecting mirror 45Y is held by a holder 52Y having a U-shaped cross-sectional shape existing on the back side thereof. And the both ends of a longitudinal direction are made to protrude from the longitudinal direction both ends of the holder 52Y, respectively.

  An inclination correction mechanism is in contact with the back surface of one end in the longitudinal direction of the second reflecting mirror 45Y. As shown in FIG. 5, the tilt correction mechanism includes a tilt adjustment pulse motor 56Y, a motor holder 57Y, a tilt adjustment adjuster 58Y, and the like.

  On the other hand, the end of the second reflecting mirror 45Y opposite to the tilt adjusting pulse motor 56Y (hereinafter referred to as “fulcrum side end”) is on a support 66 formed on the housing of the printer main body (not shown). It is on. In this state, the leaf spring 69 fixed to the housing (not shown) is pressed against the back surface, so that it is sandwiched between the support portion and the leaf spring 69.

  When the tilt adjustment adjuster (58Y in FIG. 5) screwed to the rotation shaft of the tilt adjustment pulse motor 56Y moves up and down with the rotation of the rotation shaft, the pushing amount of the tilt adjustment adjuster with respect to one end of the second reflecting mirror 45Y. Changes. Thereby, the motor side end portion of the second reflecting mirror 45Y swings in the adjuster ascending / descending direction with the fulcrum side end portion sandwiched between the support portion 66 and the leaf spring 69 as a fulcrum. Then, the tilt of the second reflecting mirror 45Y changes due to this swinging. That is, the inclination of the illustrated second reflecting mirror 45Y is adjusted by adjusting the rotation amount of the inclination adjustment pulse motor 56Y.

FIG. 7 is a configuration diagram showing a cross section near the central portion in the longitudinal direction of the second reflecting mirror 45Y and the surrounding configuration. FIG. 8 is a perspective view showing the vicinity of the central portion in the longitudinal direction of the second reflecting mirror 45Y and the surrounding configuration from the back side of the second reflecting mirror 45Y.
As shown in FIG. 7, an adjustment screw mounting surface 52fY having a surface inclined with respect to the back surface of the second reflecting mirror 45Y is provided at the center in the longitudinal direction of the holder 52. The adjustment screw mounting surface 52fY is provided with a screw hole (not shown). An adjustment screw 165Y as an adjustment member is screwed into the screw hole, and the tip of the adjustment screw 165Y is in the longitudinal direction of the second reflecting mirror 45Y. It is in contact with the back of the central part.

  As shown in FIG. 4, the holder 52Y holding the second reflecting mirror 45Y while being positioned on the back side of the second reflecting mirror 45Y has two claws 52aY arranged in the width direction of the second reflecting mirror 45Y in the longitudinal direction. At both ends. These claws 52aY are integrally formed with the main body of the holder 52Y. As shown in FIG. 4, the holder 52Y supports the second reflecting mirror 45Y on the mirror surface side by hooking the respective claws 52aY onto the mirror surface of the second reflecting mirror 45Y. As shown in FIG. 5, the holder 52Y has leaf springs 52bY as pressing members at both ends in the longitudinal direction. Each of the leaf springs 52bY biases the back surface (non-mirror surface) of the second reflecting mirror 45Y toward the mirror surface side on the end side in the longitudinal direction from the claw 52aY as a support member.

  When both end portions of the second reflecting mirror 45Y are urged from the back side by the leaf springs (52bY), the second reflecting mirror 45Y moves in the longitudinal direction with the claw 52aY as a fulcrum as shown by a dotted line in FIG. The central portion is forcibly bent so as to bend toward the back side. That is, the holder 52Y as a holding body holds the second reflecting mirror 45Y in a state in which the second reflecting mirror 45Y is forcibly bent toward the back surface side.

FIG. 10 is a perspective view of the adjustment screw 165Y viewed from the contact portion 165aY side, and FIG. 11 is a perspective view of the adjustment screw 165Y viewed from the engagement portion 165cY side. FIG. 12 is a partial cross-sectional view of the adjustment screw 165Y.
The adjustment screw 165Y includes a contact portion 165aY that contacts the back surface of the second reflecting mirror 45Y, a screw portion 165bY that is screwed into the screw hole, an engagement portion 165cY that the adjustment jig 166 engages with, and the adjustment jig 166. The guide portion 165dY is guided.
The contact portion 165aY provided at the tip of the adjustment screw 165Y has an outer diameter smaller than that of the screw portion 165bY, and an R is provided at the tip, so that the contact portion 165aY is connected to the back surface of the second reflecting mirror 45Y. The back surface of the second reflecting mirror 45Y is not damaged even if it is in contact with the back surface of the second mirror at an angle.
The engaging portion 165cY has a hexagonal hole shape, and the guide portion 165dY has a mortar shape whose diameter decreases from the opening end toward the engaging portion 165cY. The outer diameter of the so-called screw head provided with the engaging portion 165cY and the guide portion 165dY is larger than the outer diameter of the screw portion 165bY. As a result, the strength of the head is ensured, and when performing processing for forming the hexagonal hole 165cY and the guide 165dY, even if some stress is applied to the screw, deformation or breakage does not occur. And the guide can be easily processed.

  In this state, as shown in FIG. 7 and FIG. 8, the hexagon wrench 166 as the adjustment jig is engaged with the hexagon hole 165cY as the engaging portion, and the adjustment screw 165Y is rotated with the hexagon wrench 166. Then, the rear surface of the second reflecting mirror 45Y in the longitudinal direction is pushed in. Then, as indicated by an arrow B in FIG. 13, a pushing force is applied to the longitudinal center of the second reflecting mirror 45Y so as to overcome the leaf springs 52bY on both ends and begin to bend in the opposite direction. . And as shown with a dashed-dotted line or a dotted line, the 2nd reflective mirror 45Y reduces the curvature amount to a back surface side, or curves to a reverse direction.

  Although the tilt correction mechanism and the curvature correction mechanism (holder and pushing means) in the Y reflection optical system have been described, the C, M, and K reflection optical systems have the same configuration. Moreover, although the example which provided the inclination adjustment mechanism and the curvature correction mechanism in the 2nd reflective mirror was demonstrated, you may provide in a 1st reflective mirror. In addition, the example in which the tilt correction mechanism and the curvature correction mechanism are provided in all the reflection optical systems for Y, C, M, and K has been described. However, according to the tilt or the curvature of the main scanning line in any one of the reflection optical systems. Thus, when correcting the inclination or curvature of the main scanning line in another reflection optical system, it is not necessary to provide an inclination correction mechanism or a curvature correction mechanism in the reference reflection optical system. In this case, it is only necessary to provide the inclination correction mechanism and the curvature correction mechanism by a number one less than the number of laser diodes.

Next, the scanning line correction work will be described.
FIG. 14 is an explanatory diagram showing the configuration when the optical writing unit 4 in a state of being held on the mounting table of the adjusting device (not shown) is viewed from the photosensitive member axial direction.
In the present embodiment, when the optical writing unit 4 is placed on the mounting table of the adjusting device, the posture is substantially the same as the posture when the optical writing unit 4 is mounted on the apparatus main body 1 of the printer (see FIG. 1). To be. After placing the optical writing unit 4 on the mounting table of the adjusting device in such a posture, when the optical writing unit 4 is used, that is, when the optical writing unit 4 is mounted on the apparatus main body 1 of the printer, Photodetectors 201Y, 201C, 201M, and 201K each composed of a CCD or the like are disposed at locations corresponding to positions where the photoconductors 10Y, 10C, 10M, and 10K are positioned with respect to the optical writing unit 4, respectively. The photodetectors 201Y, 201C, 201M, and 201K correspond to the central portion of the photoconductor axis direction on the photoconductor surface along the direction corresponding to the photoconductor axis direction (the normal direction of the drawing in the drawing) for each color. One is arranged at each of three locations, that is, a location corresponding to both ends in the photosensitive member axial direction. In addition, the number and arrangement | positioning location of the photodetector arrange | positioned for every color are not restricted to this.

  These photodetectors 201Y, 201C, 201M, and 201K are connected to the control unit 202 of the adjustment device, and the detection results (such as the received light amount and the spot diameter) detected by the photodetectors 201Y, 201C, 201M, and 201K. Detection signal) is sent to the control unit 202. The control unit 202 performs various arithmetic processes based on the input detection signal, and continuously performs scanning line adjustment information such as the amount of received light received by each of the photodetectors 201Y, 201C, 201M, and 201K in almost real time. Are output to the display unit 203. Thereby, the operator who performs the scanning line adjustment work can rotate the adjustment screw and perform the bending adjustment of the scanning line while viewing the scanning line adjustment information displayed on the display unit 203.

  To correct the bending of the scanning line corresponding to the Y color, a hexagon wrench 166, which is an adjustment jig, is inserted in an arrow AY direction in the drawing from an adjustment hole 49Y provided in the lower cover 47. As shown in the figure, when correcting the bending of the Y scanning line, a hexagon wrench 166 is inserted from the bottom, so the tip of the hexagon wrench 166 is adjusted while visually checking the adjustment screw 165Y. It cannot be engaged with the hexagonal hole 165cY of the screw 165Y. For this reason, the position of the tip of the hexagon wrench 166 may shift. In this case, the tip of the hexagon wrench 166 abuts against the guide portion 165dY of the adjustment screw 165Y. Since the guide portion 165dY has a mortar shape whose diameter is increased from the hexagonal hole 165cY, when the hexagon wrench 166 is further inserted from the state where the hexagon wrench 166 hits the guide portion 165dY, the hexagon wrench 166 The tip is guided to the hexagonal hole 165cY by the guide portion 165dY. Therefore, even if the position of the tip of the hexagon wrench 166 is shifted, the hexagon hole 165cY can be easily accessed.

  In this embodiment, since the engaging portion is a hexagonal hole, even if the hexagonal wrench 166 and the hexagonal hole 165cY do not match, the hexagonal wrench 166 is only rotated by 30 °, The wrench 166 can be engaged with the hexagonal hole 165cY. As in the case of a normal screw, when the engaging portion is a cross hole, it is necessary to rotate about 90 ° at the maximum in order to engage the adjustment jig with the cross hole. On the other hand, the adjustment jig can be moved to the engagement portion with the maximum rotation amount (1/3) compared to the embodiment in which the engagement portion has a hexagonal hole shape as in this embodiment, and the engagement portion has a cross hole. Can be engaged. Therefore, the workability of the curvature correction can be improved compared with the cross hole.

  When the hexagon wrench 166 is guided by the guide portion 165dY provided on the adjustment screw 165Y and engaged with the hexagon hole 165cY, the hexagon wrench 166 is rotated from the outside of the optical writing unit, and the adjustment screw 165Y is rotated. To reduce the amount of bending of the second reflecting mirror 45Y toward the back surface or bend in the opposite direction, thereby correcting the bending of the Y-color scanning line.

  Similarly, when correcting the curve of the C color scanning line, a hexagon wrench 166 is inserted in the direction of the arrow Ac from the adjustment hole 49c, and the adjustment screw 165C is accessed to correct the curve of the C color scanning line. To do. When correcting the bending of the M-color scanning line, a hexagon wrench 166 is inserted in the direction of the arrow AM from the adjustment hole 49M, and the adjustment screw 165M is accessed to correct the bending of the scanning line. When correcting the bending of the scanning line of K color, a hexagon wrench 166 is inserted in the direction of the arrow AK from the adjustment hole 49K, and the adjustment screw 165K is accessed to correct the bending of the scanning line.

  In addition, the inclination of the scanning line is adjusted by driving the inclination adjustment pulse motor 56Y based on the detection results detected by the photodetectors 201Y, 201C, 201M, and 201K. Then, the tilt adjustment adjuster screwed to the rotation shaft moves up and down with the rotation of the rotation shaft, and the pushing amount of the tilt adjustment adjuster with respect to one end of the second reflecting mirror 45Y changes. As a result, the motor-side end of the second reflecting mirror 45Y swings in the adjuster ascending / descending direction with the fulcrum-side end sandwiched between the support 66 and the leaf spring as a fulcrum. Then, the tilt (posture) of the second reflecting mirror 45Y is changed by this swing, and the scanning line is corrected.

[Modification 1]
Next, Modification 1 will be described.
In the first modification, a guide is provided in a housing that is a separate member from the adjustment screw.
In the following modification 1, the adjustment hole 49C will be described, but the adjustment hole 49C can be applied to adjustment holes 49Y, 49M, and 49K of other colors.
FIG. 15 is a perspective view showing an example in which a guide is provided in the adjustment hole 49C of the housing, and FIG. 16 is a schematic cross-sectional view showing an example in which a guide is provided in the housing adjustment hole 49C.
As shown in the drawing, the outer end portion of the C color adjustment hole 49C has an opening guide 491C for guiding the hexagon wrench 166 to the adjustment hole 49C. The opening guide 491C has a mortar shape whose diameter increases from the adjustment hole 49C toward the outside. Further, as shown in FIG. 16, a second guide 492C for guiding the tip of a hexagon wrench 166 inserted into the adjustment hole 49C to the adjustment screw 165C is provided at the inner end of the adjustment hole 49C. The second guide 492C extends from the inner end of the adjustment hole 49C toward the adjustment screw 165C.

  In the first modification, by having the opening guide 491C, when the hexagon wrench 166 is inserted into the adjustment hole 49C, the insertion position of the hexagon wrench 166 is shifted from the position of the adjustment hole 49C. The wrench 166 is guided by the opening guide 491C, and the hexagon wrench 166 is inserted into the adjustment hole 49C. Thereby, the hexagon wrench 166 can be easily inserted into the adjustment hole 49C, and the workability of the scanning line adjustment can be improved. In particular, as shown in FIG. 14, it is effective to provide the opening guide in the adjustment hole 49Y where the hexagon wrench 166 needs to be inserted from below. This is because the adjustment hole 49 is in the lower cover, and the adjustment hole cannot be visually confirmed, so the tip of the hexagon wrench often deviates from the adjustment hole. Therefore, by providing the opening guide in the adjustment hole 49Y, even if the tip of the hexagon wrench is displaced from the adjustment hole, the tip is guided by the opening guide, and the tip of the hexagon wrench can be inserted into the adjustment hole.

  Further, since the hexagon wrench 166 inserted into the adjustment hole 49C is guided to the hexagon hole of the adjustment screw by the second guide 492C, the hexagon wrench 166 can be easily engaged with the hexagon hole of the adjustment screw. Can do. Thereby, the workability of scanning line adjustment can be improved.

  Furthermore, by providing a guide also on the adjustment screw, the position of the adjustment screw fluctuates due to a mounting error of the second reflecting mirror, and the position of the hexagon wrench guided by the second guide and the hexagonal hole of the adjustment screw. Even if the position of the hexagonal wrench is shifted, the hexagonal wrench can be guided by the guide of the adjusting screw and engaged with the hexagonal hole. Therefore, the workability of scanning line adjustment can be further improved.

Further, as shown in FIGS. 17 and 18, a guide may be provided on the polygon cover 46. The polygon cover 46 is extended upward so that the upper part of the polygon cover 46 overlaps the line segment connecting the adjustment hole 49C and the hexagonal hole of the adjustment screw 165C shown in FIG. A portion where the line segment connecting the adjustment hole 49C of the polygon cover 46 and the hexagonal hole of the adjustment screw 165C collides with each other to form a guide 493C. With this configuration, the hexagon wrench inserted into the adjustment hole 46C is guided by the guide 493C, and the tip of the hexagon wrench can be guided to the hexagon hole of the adjustment screw 165C.
Similarly, the guide 493M may be formed by recessing a portion where the polygon cover 46 extends upward and a line segment connecting the adjustment hole 49M and the hexagonal hole of the adjustment screw 165M hits.

  In the above description, the tilt adjustment is adjusted using a pulse motor provided inside the apparatus. However, as in the case of bending adjustment, the adjustment screw is inserted and an adjustment jig is inserted from the outside of the apparatus. The inclination may be corrected. Even in this case, by providing a guide on the adjustment screw or the housing, the adjustment jig for adjusting the inclination is guided by the guide, and the adjustment jig and the adjustment screw can be easily engaged. Thereby, the inclination adjustment work can be easily performed.

In the above description, the writing unit that focuses light in the sub-scanning line direction and the main scanning line direction with one scanning lens has been described. However, as shown in FIG. 19, scanning that condenses light in the sub-scanning direction. The present invention can also be applied to an optical writing unit including a lens (long lens) and a scanning lens (fθ lens) that focuses light in the main scanning line direction.
Further, in the optical writing unit including the scanning lens (long lens) for condensing in the sub-scanning direction and the scanning lens (fθ lens) for condensing in the main scanning line direction shown in FIG. Instead, the inclination or bending of the scanning line may be corrected by changing or bending the posture of the scanning lens (long lens) that collects light in the sub-scanning direction.

FIG. 20 is a schematic configuration diagram of a curvature correction mechanism that corrects the bending of a scanning line by using a long lens.
As shown in FIG. 20, the bending correction mechanism includes a bracket, a bending adjustment spring, a fixing spring, an adjustment screw, and the like.
Both ends of the long lens in the longitudinal direction are fixed to the bracket 352 by fixing plate springs 354 and 355. An adjustment screw is screwed to the longitudinal center of the bracket.
When the adjustment screw 365 is not tightened, the central portion in the longitudinal direction of the long lens 351 is urged toward the top surface of the bracket 352 by the bending adjustment plate spring 353. In this state, when the adjustment jig is engaged with the adjustment screw 365 and the adjustment screw 365 is tightened by the adjustment jig, the contact portion that is the top of the adjustment screw 365 is located at the center in the longitudinal direction of the long lens 351. Abutting, and the space between this portion and the top surface of the bracket 352 increases. Both ends of the long lens 51 in the longitudinal direction are fixed to the bracket 352 by fixing plate springs 354 and 355, and the rigidity of the long lens 351 is lower than that of the bracket 352. Therefore, by tightening the adjustment screw 365, the long lens 351 is bent in the longitudinal direction as shown in FIG. When the long lens 351 is bent in this manner, the degree of bending of the scanning line by the laser light passing through the long lens 351 changes according to the amount of bending. Therefore, the bending of the scanning line can be corrected by adjusting the tightening amount of the bending adjustment screw 365.

In the configuration in which the bending of the scanning line is corrected by the long lens, as shown in FIG. 19, the adjustment jig is engaged with the adjustment screw of the bending correction mechanism provided in the long lens unit 50a or 50d. In this case, it is necessary to insert the adjustment jig from the lower surface of the housing.
Therefore, even in such a configuration, the bending adjustment work can be easily performed by providing the guide of the present invention on the adjustment screw, the housing, or the like.

FIG. 21 is a schematic configuration diagram of an inclination correction mechanism that corrects an inclination of a scanning line using a long lens.
The central portion in the longitudinal direction of the bottom surface of the long lens fixed to the bracket (the surface located on the side opposite to the top surface of the bracket 352) is supported by a kamaboko-shaped support base 366 fixed to the housing. Further, the abutting portion that is the top of the inclination adjusting screw is brought into contact with the end portion of the bracket.

  Further, unit support leaf springs 361 and 362 fixed to the housing are in contact with both longitudinal ends of the top surface of the bracket 352. Due to the urging force of the unit supporting leaf springs 361 and 362, both longitudinal ends of the top surface of the bracket 352 receive a force that is pushed down toward the bottom surface side. Accordingly, the long lens unit 50 includes a tilt adjusting screw 363, a unit support leaf spring 361, a support base 366, in a direction (vertical direction) orthogonal to both the longitudinal direction of the long lens 351 and the direction of the optical path L. It is supported by a unit support leaf spring 362.

  When the adjustment jig is inserted into the apparatus, the adjustment jig is engaged with the adjustment screw 363, and the adjustment screw 363 is rotated to raise the adjustment screw 363, the end of the long lens unit 50 on the adjustment screw side is The unit supporting plate spring 361 rises against the biasing force. Thus, the long lens unit 50 rotates clockwise in FIG. 21 with the support base 366 as a fulcrum, and changes its posture. On the other hand, when the adjustment screw is lowered, the adjustment screw side end portion of the long lens unit 50 is lowered by the urging force of the unit supporting plate spring 361. Accordingly, the long lens unit 50 rotates counterclockwise in FIG. 21 with the support base 366 as a fulcrum, and changes its posture.

  When the posture of the long lens unit 50 changes in this way, the position where the laser light L enters the incident surface of the long lens 351 changes. When the incident position of the laser beam L with respect to the incident surface of the long lens 351 changes in a direction (vertical direction) perpendicular to the longitudinal direction of the long lens 351 and the direction of the optical path, the long lens 351 changes the length of the long lens 351. It has the characteristic that the angle (emitting angle) with respect to the vertical direction of the laser beam emitted from the emitting surface changes. Due to this characteristic, when the posture of the long lens unit 50 is changed by the elevating screw, the emission angle of the laser beam emitted from the emission surface of the long lens 351 is changed accordingly. As a result, the photosensitive member by this laser beam is changed. The slope of the upper scan line changes.

  Even in the tilt correction mechanism that corrects the scan line tilt by changing the posture of the long lens, the tilt adjustment jig can be easily adjusted for tilt adjustment by providing the guide of the present invention on the adjustment screw, housing, etc. It can be engaged with the screw, and the scan line tilt correction operation can be easily performed.

  In the above description, the scanning line inclination correction / bending correction is performed by being placed on the adjustment device for adjusting the inclination or bending of the scanning line. However, the optical scanning device is placed on the image forming apparatus. Bend correction and inclination correction can be performed. In this case, first, a pattern image for examining the curve or inclination of the scanning line is formed on the intermediate transfer belt or the like, and the pattern image is detected by an optical sensor. Based on the detection result, the bending amount and the inclination amount of the scanning line are calculated and displayed on the display of the image forming apparatus. The operator performs tilt adjustment and bend adjustment based on the display.

In the optical writing unit that is the optical scanning device of the present embodiment, a laser diode that is a light source, a polygon scanner that is a scanning unit that irradiates a photoconductor that is a light irradiation target and scans the photosensitive member, and And an optical element such as a reflection mirror or a long lens provided on an optical path from the laser diode to the photosensitive member. In addition, a bending correction mechanism is provided as correction means for correcting the bending of the scanning line by bending the reflecting mirror and the long lens. The bending correction mechanism has an abutting portion that abuts on the reflection mirror (long lens) and an engaging portion that engages with an adjusting jig inserted from the outside of the apparatus, and can be applied with force from the adjusting jig. The position of contact with the reflecting mirror (long lens) is displaced, and an adjusting screw is provided as an adjusting member for adjusting the curvature of the reflecting mirror (long lens). A guide is provided for guiding the adjustment jig inserted from the outside of the mounted optical writing unit to the engagement portion of the adjustment screw.
Thus, when the adjustment jig is engaged with the engagement portion of the adjustment member, the adjustment jig is guided to the engagement portion of the adjustment member by the guide, so even if the position of the adjustment member cannot be confirmed visually, The adjustment jig can be easily engaged with the adjustment screw. As a result, the scanning line correction operation can be easily performed.

  Further, by providing the guide on the adjustment screw, the adjustment jig inserted into the housing can be guided to the engaging portion of the adjustment screw.

  In addition, because the guide has a mortar shape with a smaller diameter toward the engaging portion, the adjustment screw can be smoothly engaged when the adjustment jig is inserted after the tip of the adjustment jig hits the guide. Can be guided to the department.

  Further, by making the shape of the engaging portion a hexagonal hole, the maximum rotation amount for engaging the adjusting jig with the engaging portion is (1 / 3), and the adjustment jig can be easily engaged with the engagement portion of the adjustment screw, compared to the case where the engagement portion is a cross hole.

  Further, by making the outer diameter of the portion where the hexagonal hole of the adjustment screw is formed larger than the outer diameter of the screw portion, the strength of the adjustment screw when forming the hexagonal hole can be increased. Deformation of the adjustment screw that occurs when forming a square hole can be suppressed, and the occurrence of defective products of the adjustment screw can be suppressed.

  The adjustment jig can be guided to the adjustment screw by providing a guide on a member other than the adjustment screw.

  By providing the guide in the housing, the adjustment jig can be guided to the adjustment screw.

  In addition, the scan line inclination correction and the curve correction can be corrected by changing the posture and shape of the long lens or the reflecting mirror that collects light in the sub-scan line direction.

4: Optical writing unit (optical scanning device)
5: Intermediate transfer unit (transfer means)
10Y, C, M, K: photoconductor (scanning object, latent image carrier)
12Y, C, M, K: Developing device (developing means)
41a, b: Polygon mirror (part of deflection means)
44Y, C, M, K: First reflecting mirror 45Y, C, M, K: Second reflecting mirror 52Y: Holder (holding body, part of curvature correction mechanism)
52aY: Claw (supporting member)
52bY: leaf spring (pressing member)
56Y: Tilt adjustment pulse motor (part of tilt correction mechanism)
57Y: Motor holder (part of tilt correction mechanism)
58Y: Tilt adjustment adjuster (part of tilt correction mechanism)
65Y: Bending adjustment pulse motor (part of pressing means, part of curvature correction mechanism)
67Y: Motor holder (part of pressing means, part of curvature correction mechanism)
68Y: Bend adjustment adjuster (part of pressing means, part of curvature correction mechanism)

JP 2006-17881 A

Claims (8)

A light source;
A scanning means for irradiating the light irradiation target with the light irradiated from the light source and scanning the same; an optical element provided on an optical path from the light source to the light irradiation target;
In an optical scanning apparatus comprising a correction unit that corrects an inclination or a curve of a scanning line by adjusting a posture or a shape of the optical element, and a housing that houses the optical element and the correction unit.
The correction means includes a contact portion that contacts the optical element, and an engagement portion that engages with an adjustment jig inserted from an adjustment hole provided in the housing. An adjustment member that adjusts a posture or a shape of the optical element by adding a displacement position of the contact portion of the contact portion with the optical element by being added;
The optical element comprises a planar portion;
The contact portion is configured to move in an inclined direction with respect to a normal direction of the planar portion ,
An engagement guide for guiding the adjustment jig inserted from the adjustment hole to the engagement portion of the adjustment member is provided, and the engagement guide is provided between the adjustment hole and the engagement portion. An optical scanning device characterized in that the adjusting jig is guided in an inclined direction .   The optical scanning device according to claim 1.
The optical scanning device, wherein the engagement guide extends from the adjustment hole toward the adjustment member. The optical scanning device according to claim 1 or 2 ,
The optical scanning device according to claim 1, wherein the adjustment hole has an opening guide that guides the adjustment jig toward the adjustment hole. The optical scanning device according to any one of claims 1 to 3 ,
An optical scanning device comprising a mortar-shaped second engagement guide provided on the adjustment member and having a diameter that decreases toward the engagement portion. In the optical scanning device in any one of Claims 1 thru | or 4,
An optical scanning device characterized in that the engaging portion is a hexagonal hole. The optical scanning device according to claim 5.
The adjustment member has a screw portion,
An optical scanning device characterized in that an outer diameter of a portion of the adjustment member where the hexagonal hole is formed is larger than an outer diameter of the screw portion . In one of the optical scanning device 請 Motomeko 1 to 6,
The optical scanning device, wherein the optical element is a lens or a mirror. Image forming apparatus characterized by mounting one of the optical scanning apparatus according to claim 1 to 7.

Images