JP2011002554A - Curvature correction mechanism, optical scanner, image forming apparatus and method of manufacturing optical scanner - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a curvature correction mechanism in which the vibration of a reflecting mirror is suppressed, the bow of main scanning line is excellently corrected, the large dimensions, the reduction in margin of layout and increase in the cost of the apparatus are suppressed, and to provide an optical scanner, to provide an image forming apparatus and a method of manufacturing the optical scanner.SOLUTION: In the original state immediately after an apparatus is assembled, a predetermined gap is formed between the lower face of a reflection mirror 45Y and a double-sided tape 120Y. In this state, the bow of main scanning line on a photoreceptor is adjusted as is described in the foregoing section. After the bow of the main scanning line is adjusted, the upper face of the reflecting mirror 45Y is depressed downward by using a stick-shaped tool from a cutout part 52cY of a holder 52Y, the lower face of the reflection mirror 45Y is brought into press contact with the double-sided tape 120Y, the lower face of the reflecting mirror 45Y is fixed on the lower face of the holder 52Y with the double-sided tape 120Y.

Description

  The present invention relates to a curvature correction mechanism, an optical scanning device, an image forming apparatus, and a method for manufacturing the optical scanning device.

  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, a deflecting unit including a polygon mirror, an fθ lens, a reflecting mirror, and the like. The light beam emitted from the light source as the light beam emitting means is guided to the surface of the latent image carrier by reflection by the reflecting mirror while being deflected in the main scanning direction by the deflecting means or condensed by the fθ lens.

  In the optical writing apparatus having the above-described configuration, subtle distortions due to processing errors during manufacturing are inevitably generated in the optical system components and supports constituting the optical writing device. 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 due to these distortions, assembly errors, and the like. When such a curve occurs, a normal image cannot be formed.

  The curve of the main scanning line is a stack of intersections of various components constituting the optical scanning device, such as distortions and assembly errors, and therefore the amount of bending and the direction of bending differ from product to product. For this reason, in order to perform normal optical scanning, the main scanning line is curved on the surface of the latent image carrier in the upstream or downstream direction in the sub-scanning direction (latent image carrier surface movement direction). Even so, it is necessary to be able to correct it.

Therefore, an optical writing device provided with a bending correction mechanism that corrects the bending of the main scanning line on the photosensitive member by adjusting the amount of bending while bending the reflecting mirror of the scanning optical system is known.
FIG. 21 is an enlarged configuration diagram showing the reflecting mirror 46 and the curvature correcting mechanism. The reflecting mirror 46 is one of a plurality of reflecting mirrors that finally guides a writing light beam (not shown) to a photosensitive member (not shown) by reflecting back and forth over a plurality of times. The reflecting mirror 46 is held by a holder 52 that is a holding body disposed on the back surface (non-mirror surface) side thereof.
Support protrusions 52 a that protrude toward the reflecting mirror 46 are provided at both ends in the longitudinal direction of the holder 52, and the supporting protrusions 52 a are in contact with the back surface of the reflecting mirror 46. A leaf spring member 54 serving as a pressing member is attached to the center side in the longitudinal direction from the support protrusion 52 a at the end of the holder 52. Each leaf spring member 54 presses the reflecting mirror 46 from the mirror surface side toward the back surface side. As a result, the reflecting mirror 46 is bent and held in the holder 52 so as to bend the central portion in the longitudinal direction from the mirror surface side toward the back surface side. On the back side of the holder 52, a pushing device serving as a forcible bending means for pushing the central portion in the longitudinal direction of the reflecting mirror 46 in the direction opposite to the bending direction of the reflecting mirror 46 (in the direction of arrow B in the figure) via the holder 52. 64 is arranged.

  FIG. 22 is a schematic diagram showing an initial curved state of the reflecting mirror 46. In a state in which the unillustrated pushing device (64 in FIG. 20) does not push the reflecting mirror 46, the reflecting mirror 46 is curved from the mirror surface side toward the back surface side as indicated by an arrow R in the drawing. From this state, when the reflecting mirror 46 is slightly pushed in the direction of arrow B in the figure by the pushing device 64, the amount of bending of the reflecting mirror 46 decreases. When the reflecting mirror 46 is further pushed in by the pushing device 64, the reflecting mirror 46 is bent in the direction opposite to the initial state. In this way, by allowing the reflecting mirror 46 to bend in any direction on the back surface side and the mirror surface side, any one of the main scanning line Lb indicated by the solid line and the main scanning line Lc indicated by the one-dot chain line in FIG. The curvature can also be corrected to a reference line La indicated by a dotted line.

  The reflecting mirror 46 has low rigidity so that it can be easily bent, and is simply held by the holder 52 so that both ends thereof are sandwiched between the support protrusion 52a and the leaf spring member 54, and is fixed to a member having high rigidity. It has not been done. For this reason, when the reflecting mirror 46 vibrates due to the vibration of a vibration source such as a motor, the amplitude increases, banding or the like occurs in the formed image, and the quality deteriorates. For this reason, reducing the vibration of the reflecting mirror 46 is an extremely important issue. As a method of reducing the vibration of the reflecting mirror 46, as shown in FIGS. 24 and 25, a method is known in which a reinforcing member 70 is fixed to the reflecting mirror 46 to increase the rigidity of the reflecting mirror (for example, Patent Documents). 1). By increasing the rigidity of the reflecting mirror 46, the amplitude during vibration can be reduced.

  In Patent Document 2, as shown in FIG. 26, the back surface 46 a of the reflecting mirror 46 is formed so that a certain gap is formed between the longitudinal center portion of the back surface 46 a of the reflecting mirror 46 and the reinforcing member 70. A method is described in which the reinforcing member 70 is fixed to both ends via an adhesive 130 to increase the rigidity of the reflecting mirror.

  However, as described in Patent Document 1, if the reinforcing member 70 is fixed to the reflecting mirror 46 for correcting the curvature of the main scanning line, the rigidity of the reflecting mirror 46 increases, and the reflecting mirror 46 becomes difficult to bend. End up. As a result, the curvature of the main scanning line cannot be corrected well. Also in Patent Document 2, since the end portion of the reflecting mirror 46 is fixed to the reinforcing member 70, the rigidity of the end portion of the reflecting mirror 46 is increased and it is difficult to bend the reflecting mirror 46. Further, since the reinforcing member 70 is provided between the holder 52 and the reflecting mirror 46, a space for providing the reinforcing member 70 is required between the holder 52 and the reflecting mirror 46, and the apparatus is increased in size and layout. The margin of will decrease. Furthermore, since the reinforcing member 70 reinforces the number of parts, the cost of the apparatus is increased. Moreover, since the central part of the reflecting mirror is not fixed, the reinforcing effect by the reinforcing member is weak, the rigidity of the reflecting mirror cannot be sufficiently increased, and the vibration suppressing effect cannot be sufficiently obtained.

  The bending correction mechanism in which the reflecting mirror is held in the holder without being bent and the reflecting mirror can be bent to either the back side or the mirror side by a pushing device as a forced bending means is the same as described above. Challenges arise.

  The present invention has been made in view of the above-mentioned problems, and the object thereof is to satisfactorily correct the main scanning line curve, and without newly providing a member for increasing the rigidity of the reflecting mirror. Another object of the present invention is to provide a bending correction mechanism, an optical scanning device, an image forming apparatus, and a method for manufacturing the optical scanning device that can suppress the vibration of the reflecting mirror.

In order to achieve the above object, the invention of claim 1 is directed to a light beam emitting means, a deflecting means for deflecting the light beam emitted from the light beam emitting means in a main scanning direction, and a reflection for reflecting the light beam. Used in an optical scanning apparatus that optically scans an object to be scanned with the light beam, and a holding body that holds the reflecting mirror so as to be bendable, and the reflecting mirror held on the holding body is orthogonal to the mirror surface. A bending correction mechanism for forcibly bending the main scanning line by correcting the bending of the main scanning line on the surface of the scanning object by adjusting a pushing amount by the forced bending means. A fixing means for fixing the reflecting mirror in a state in which the curvature of the line is corrected to the holding body having higher rigidity than the reflecting mirror is provided.
The invention according to claim 2 is the curvature correction mechanism according to claim 1, wherein the fixing means is a double-sided tape, and the reflection mirror is in a state before being fixed to the holding body by the double-sided tape. The mirror is held by the holding body so as to be movable in a direction perpendicular to a surface to which the double-sided tape of the reflecting mirror is attached.
The invention according to claim 3 is the bending correction mechanism according to claim 1, wherein the fixing means is a pressing member that presses the reflecting mirror against the holding body, and the bending correction of the main scanning line is performed by the pressing member. The reflecting mirror in a state in which the curvature of the main scanning line is corrected is fixed to the holding body by pressing the reflecting mirror in the prepared state against the holding body.
According to a fourth aspect of the present invention, in the curvature correcting mechanism according to the third aspect, an elastic sheet member is attached to a surface of the holding body against which the reflecting mirror is pressed.
The invention of claim 5 is characterized in that, in the curvature correcting mechanism of claim 1, an adhesive is used as the fixing means.
The invention of claim 6 is characterized in that, in the curvature correction mechanism of claim 5, an ultraviolet curable adhesive is used as the adhesive.
According to a seventh aspect of the present invention, in the bending correction mechanism according to the sixth aspect, the holder is provided with a transmission part through which the ultraviolet rays are transmitted.
The invention of claim 8 is characterized in that, in the curvature correcting mechanism of claim 1, a slow-acting double-sided tape is used as the fixing means.
The invention according to claim 9 is characterized in that, in the curvature correcting mechanism according to any one of claims 1 to 8, a longitudinal side surface of the reflecting mirror orthogonal to the mirror surface of the reflecting mirror is fixed to the holding body. To do.
According to a tenth aspect of the present invention, there is provided a light beam emitting means, a deflecting means for deflecting the light beam emitted from the light beam emitting means in a main scanning direction, a reflecting mirror for reflecting the light beam, and a scanning object. 10. As an optical scanning apparatus for optically scanning the object to be scanned with the light beam, the curvature correcting unit includes a curvature correcting unit that corrects the curvature of the main scanning line on the surface of the main scanning line. It is characterized by using a curvature correction mechanism.
The invention according to claim 11 is a latent image carrier for carrying a latent image, optical scanning means for forming a latent image on the surface of the latent image carrier by optical scanning, and the latent image carrier. An image forming apparatus including a developing unit that develops a latent image uses the optical scanning device according to claim 10 as the optical scanning unit.
The invention of claim 12 is a light beam emitting means, a deflecting means for deflecting the light beam emitted from the light beam emitting means in a main scanning direction, a reflecting mirror for reflecting the light beam, and the reflecting mirror. A forcible bending means for forcibly bending by pushing in a direction perpendicular to the mirror surface, and a bending correction means for correcting the curvature of the main scanning line on the surface of the scanning object by adjusting the amount of pushing by the forced bending means. In the manufacturing method of the optical scanning device that optically scans the scanning object with the light beam, after correcting the curvature of the main scanning line by the curvature correcting means, the reflecting mirror after the curvature correction of the main scanning line, It has the process of fixing to the holding body holding the said reflective mirror with a double-sided tape, It is characterized by the above-mentioned.
The invention of claim 13 is a light beam emitting means, a deflecting means for deflecting the light beam emitted from the light beam emitting means in a main scanning direction, a reflecting mirror for reflecting the light beam, and the reflecting mirror. A forcible bending means for forcibly bending by pushing in a direction perpendicular to the mirror surface, and a bending correction means for correcting the curvature of the main scanning line on the surface of the scanning object by adjusting the amount of pushing by the forced bending means. In the manufacturing method of the optical scanning device that optically scans the scanning object with the light beam, after correcting the curvature of the main scanning line by the curvature correcting means, the reflecting mirror after the curvature correction of the main scanning line, It has the process of pressing and fixing to the holding body holding the said reflecting mirror with a pressing member.
The invention according to claim 14 is a light beam emitting means, a deflecting means for deflecting the light beam emitted from the light beam emitting means in a main scanning direction, a reflecting mirror for reflecting the light beam, and the reflecting mirror. A forcible bending means for forcibly bending by pushing in a direction perpendicular to the mirror surface, and a bending correction means for correcting the curvature of the main scanning line on the surface of the scanning object by adjusting the amount of pushing by the forced bending means. In the manufacturing method of the optical scanning device that optically scans the scanning object with the light beam, after correcting the curvature of the main scanning line by the curvature correcting means, the reflecting mirror after the curvature correction of the main scanning line, It has the process of fixing to the holding body holding the said reflective mirror with an adhesive agent, It is characterized by the above-mentioned.

According to the present invention, the reflecting mirror in a state in which the curvature of the main scanning line is corrected is fixed to the holding body having higher rigidity than the reflecting mirror by the fixing means, so that the rigidity of the reflecting mirror can be increased by the holding body. Thereby, the amplitude when the reflecting mirror vibrates is reduced. As a result, image degradation such as banding can be suppressed. Further, at the time of curvature correction, the reflecting mirror is merely held by the holding body so as to be bent, and is not fixed to the holding body. Therefore, at the time of curvature correction, the reflecting mirror is not enhanced in rigidity, so that the reflecting mirror can be easily bent and the main scanning line can be favorably corrected.
In addition, the rigidity of the reflecting mirror is increased by fixing the reflecting mirror in a state in which the curvature of the main scanning line is corrected to the holding body, and therefore, compared to the case where a member for increasing the rigidity of the reflecting mirror is newly provided. An increase in the number of points can be suppressed, and an increase in the cost of the apparatus can be suppressed. In addition, since it is not necessary to secure a space for fixing a member for increasing the rigidity of the reflecting mirror to the reflecting mirror, it is possible to suppress an increase in the size of the apparatus and a reduction in layout margin.

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 schematic diagram explaining the forced bending of the said 2nd reflective mirror. 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. The block diagram which shows the structure which supports the back surface of a reflective mirror with a supporting member, and energizes the mirror surface of a 2nd reflective mirror toward a back surface side with a pressing member. FIG. 6 is a top view illustrating a curvature correction mechanism and a second reflecting mirror according to the first embodiment. Sectional drawing which shows the curvature correction mechanism and 2nd reflective mirror of Example 1 before main scanning line curvature correction. FIG. 3 is a perspective view of a holder in the curvature correction mechanism according to the first embodiment. Sectional drawing which shows the curvature correction mechanism and 2nd reflective mirror of Example 1 after main scanning line curvature correction | amendment. FIG. 6 is an enlarged configuration diagram in the vicinity of a central portion in a longitudinal direction of a curvature correction mechanism according to a second embodiment. Sectional drawing which shows the curvature correction mechanism and 2nd reflective mirror of Example 2 after main scanning line curvature correction | amendment. Sectional drawing which shows the modification of the curvature correction mechanism of Example 2. FIG. FIG. 9 is an enlarged configuration diagram in the vicinity of an end in a longitudinal direction of a curvature correction mechanism according to a third embodiment. FIG. 10 is a perspective view of a holder in the curvature correction mechanism of the third embodiment. FIG. 10 is a perspective view illustrating a modification of the curvature correction mechanism according to the third embodiment. The expansion block diagram which shows a reflective mirror and a curvature correction mechanism. The schematic diagram which shows the same reflective mirror in the state bent forcibly. FIG. 3 is a schematic diagram showing a corrected main scanning line on the surface of a photoreceptor. The figure which shows an example which attached the reinforcement member to the reflective mirror. The figure which shows the other example which attached the reinforcement member to the reflective mirror. The figure which shows the further another example which attached the reinforcement member to the reflective mirror.

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 to 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.
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.

  The inclination of the main scanning line on the photosensitive member is adjusted at the time of shipment of the printer, and at the time of operation of the printer, for example, a predetermined timing such as a timing when the number of prints reaches a predetermined number or a timing when a user instruction is received. But it is done. In the tilt adjustment, first, an electrostatic latent image for detecting a predetermined misregistration is formed on the photoconductors 10Y, 10C, 10M, and 10K of the respective colors shown in FIG. 3 by the same operation as the normal image forming operation. Is done. Then, the electrostatic latent image for detecting the misregistration of each color is developed by the same operation as that in the normal image forming operation, and becomes a toner image for detecting misregistration of each color. When these toner images are primarily transferred at positions shifted from each other on the intermediate transfer belt, the toner images of the respective colors become the position shift detection pattern images arranged in a predetermined pattern. Thereafter, with the endless movement of the intermediate transfer belt, each toner image of the misregistration detection pattern image on the belt is detected by an optical sensor (not shown). A control unit (not shown) of the printer grasps the relative positional deviation of each toner image based on the detection timing of each toner image by the optical sensor. Based on the grasped result, the inclination amount of the main scanning line for other colors (Y, C, M) with respect to the main scanning line for black (K) that can minimize the amount of positional deviation of each toner image is calculated. . Next, based on the calculation result, the tilt adjustment pulse motor (for example, 56Y) is rotated forward or backward by a predetermined rotation angle. When the tilt of the reflecting mirror is changed by this, the incident position of the writing light L with respect to the mirror surface is changed, so that the tilt of the main scanning line on the photosensitive member is changed. As a result, it is possible to correct the inclination of the scanning line generated before adjustment.

  The curve adjustment of the main scanning line on the photoconductor is performed when the printer is shipped. In the initial state immediately after the assembly of the apparatus, the reflecting mirror is curved as shown by the dotted line in FIG. In such an initial state, the main scanning line also has a curved shape. From this initial state, the hexagon wrench 166, which is an adjustment jig shown in FIG. 7, is engaged with a hexagon hole 165cY (not shown) provided in the adjustment screw, and the adjustment screw 165Y is rotated by the hexagon wrench 166. The back surface of the central part in the longitudinal direction of the second reflecting mirror 45Y is pushed in. Then, as indicated by an arrow B in FIG. 9, a pushing force is applied to the central portion of the second reflecting mirror 45Y in the longitudinal direction 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.

  In the reflection optical system having such a configuration, as already described, the second scanning mirror 45Y can be curved in any direction on the back surface side and the mirror surface side, so that the main scanning line on the surface of the photoreceptor (not shown) can be obtained. Any of the curves toward the upstream side and the downstream side in the sub-scanning direction can be corrected.

  In the above description, the configuration in which the mirror surface of the reflecting mirror 45Y is supported by the support member and the back surface (non-mirror surface) of the second reflecting mirror 45Y is urged toward the mirror surface side by the pressing member has been described. As shown, the back surface of the reflecting mirror may be supported by a support member, and the mirror surface of the second reflecting mirror 45Y may be biased toward the back surface side by a pressing member.

  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. 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.

  Sudden vibrations caused by impacts such as vibrations caused by rotation of the polygon motor, gears of the driving device, and clutches during image formation propagate to the housing. The vibration propagated to these housings is generally low frequency. Such low-frequency vibration propagates to the second reflecting mirror 45Y through the housing.

  Since the end of the second reflecting mirror 45Y on the side of the tilt adjusting pulse motor 56Y is sandwiched and supported between the tilt adjusting adjuster 58Y and a relatively weak spring (not shown), the end on the side of the tilt adjusting pulse motor 56Y is supported. The second reflecting mirror 45Y is easily vibrated under the influence of the vibration propagated to the housing. The second reflecting mirror 45Y is only held by the holder 52Y as a holding body so that it can be bent, and is not fixed to a highly rigid member, and the second reflecting mirror 45Y has a longitudinal direction. The rigidity is low because it is long. For this reason, the amplitude when the second reflecting mirror 45Y vibrates is large. The second reflecting mirror is low in rigidity and long in the longitudinal direction, and thus has a low natural frequency, and therefore tends to resonate with low-frequency vibrations propagated by the housing. As a result, the second reflecting mirror vibrates greatly. The holder 52Y holds the second reflecting mirror 45Y without being fixed to the housing. For this reason, when the second reflecting mirror 45Y vibrates, the holder 52Y also vibrates due to the vibration. Then, the vibration of the holder 52Y propagates to the second reflecting mirror 45Y, and the second reflecting mirror 45Y vibrates in a complicated mode instead of the primary simple mode.

  Therefore, the thickness of the second reflecting mirror 45Y is increased or a reinforcing member is attached to the second reflecting mirror 45Y to increase the rigidity of the reflecting mirror 45Y and reduce vibration (amplitude during vibration). It is also conceivable that the natural frequency of the two reflecting mirror 45Y is increased to make it difficult to resonate with the low frequency vibration propagating to the housing. However, if the rigidity of the second reflecting mirror 45Y is increased, it becomes difficult to forcibly bend, and it is difficult to correct the curvature of the scanning line.

  Therefore, in the present embodiment, the second reflecting mirror 45Y after the curvature correction is fixed to the holder 52Y, the rigidity of the second reflecting mirror 45Y is increased by the holder 52Y, and the vibration of the second reflecting mirror is reduced. Hereinafter, a configuration for fixing the second reflecting mirror 45Y after the curvature correction, which is a characteristic point of the present embodiment, to the holder 52Y will be described in detail using an example.

FIG. 11 is a top view showing the curvature correcting mechanism and the second reflecting mirror of Example 1, and FIG. 12 is a cross-sectional view taken along the line AA of FIG. 11 before the curvature correction. FIG. 13 is a perspective view of the holder 52Y of the curvature correction mechanism according to the first embodiment.
In the first embodiment, as shown in FIGS. 12 and 13, a double-sided tape 120Y as a fixing means is attached to the lower surface of the holder 52Y in the longitudinal direction. Further, as shown in FIG. 11, a notch 52cY is formed at a predetermined distance in the longitudinal direction from the longitudinal center of the upper surface of the holder 52Y, and the upper surface of the reflecting mirror is exposed from the notch 52cY. ing.

  In an initial state immediately after the assembly of the apparatus, as shown in FIG. 12, a predetermined gap is formed between the lower surface of the reflecting mirror 45Y and the double-sided tape 120Y. In this state, the curvature of the main scanning line on the photosensitive member is adjusted as described above. After adjusting the curvature of the main scanning line, the upper surface of the reflecting mirror 45Y is pushed downward from the notch 52cY portion of the holder 52Y using a bar-shaped jig. The reflecting mirror 45Y is only sandwiched in the optical axis direction by the claw 52aY of the holder 52Y and the leaf spring, and the reflecting mirror 45Y is movable in the vertical direction with respect to the holder 52Y. Therefore, when the upper surface of the reflecting mirror 45Y is pushed downward from the notch 52cY portion of the holder 52Y using a bar-shaped jig, the reflecting mirror 45Y moves downward. The lower surface of the reflecting mirror 45Y is pressed against the double-sided tape 120Y, and the lower surface of the reflecting mirror 45Y is fixed to the lower surface of the holder 52Y by the double-sided tape 120Y (see FIG. 14). Thus, by fixing the second reflecting mirror 45Y to the holder 52Y, the rigidity of the second reflecting mirror 45Y can be increased, and the amplitude when the second reflecting mirror 45Y vibrates can be suppressed. Further, the natural frequency of the second reflecting mirror 45Y is increased, and the natural frequency of the second reflecting mirror 45Y can be separated from the low frequency vibration propagated to the housing. As a result, the second reflecting mirror 45Y does not resonate with the low-frequency vibration propagated to the housing, and the vibration of the second reflecting mirror 45Y can be suppressed.

  Since the second reflecting mirror 45Y is not fixed to the holder 52Y before the main scanning line curvature is corrected, the second reflecting mirror 45Y can be favorably bent at the time of correcting the main scanning line curvature. it can. Thereby, the curvature of the main scanning line can be corrected satisfactorily.

  Further, a slow-acting double-sided tape may be used as the double-sided tape 120Y. The slow-acting double-sided tape is a double-sided tape that does not have a sufficient adhesive force immediately after being applied, and increases with time. Therefore, when this slow-acting double-sided tape is used, the lower surface of the reflecting mirror 45Y is brought into close contact with the double-sided tape 120Y during assembly (before the curvature correction), and the lower surface of the reflecting mirror 45Y is adhered to the slow-acting double-sided tape. Temporarily fixed to the lower surface of the holder 52Y. Then, before the adhesive force of the slow-acting double-sided tape is increased, the curvature of the main scanning line is corrected. After the main scanning line curvature correction is performed, the adhesive force of the slow-acting double-sided tape increases with time, and the lower surface of the reflecting mirror 45Y is fixed to the lower surface of the holder 52Y by the double-sided tape 120Y. By using the slow-acting double-sided tape, there is an advantage that it is not necessary to press the lower surface of the reflecting mirror 45Y against the double-sided tape 120Y after correcting the curvature of the main scanning line.

  In the above description, the reflecting mirror 45Y is pushed with a jig and the reflecting mirror 45Y is moved with respect to the holder 52Y and fixed to the double-sided tape 120Y. However, the holder 52Y is pushed with the jig and the holder 52Y is moved to the reflecting mirror. It may be moved with respect to 45Y and fixed with double-sided tape 120Y. In the first embodiment, the double-sided tape 120Y is attached to the lower surface of the holder 52Y. However, the double-sided tape 120Y is attached to the upper surface of the holder 52Y and the reflecting mirror 45Y is pushed upward to reflect the upper surface of the holder 52Y. The upper surface of the mirror 45Y may be fixed with a double-sided tape 120Y.

FIG. 15 is an enlarged configuration diagram in the vicinity of the central portion in the longitudinal direction of the curvature correction mechanism of the second embodiment, and FIG. 16 is a cross-sectional view of the curvature correction mechanism of the second embodiment.
The curvature correcting mechanism of the second embodiment is such that the second reflecting mirror 45Y is pressed against the lower surface of the holder 52Y with a screw 121Y as a pressing member, and the reflecting mirror 45Y is sandwiched and fixed to the holder 52Y with the lower surface of the holder 52Y and the screw 121Y. is there.
As shown in FIG. 15, a screw hole having a screw groove formed on the inner peripheral surface is formed at the longitudinal center of the upper surface of the holder, and a screw 121 </ b> Y is screwed into the screw hole.

  In the initial state immediately after the assembly of the apparatus, the tip of the screw 121Y is not in contact with the upper surface of the reflecting mirror 45Y, and in this state, the curvature of the main scanning line on the photosensitive member is adjusted as described above. When the screw 121Y is tightened after adjusting the curvature of the main scanning line, the tip of the screw 121Y comes into contact with the upper surface of the reflecting mirror 45Y. As the screw 121Y is further tightened, the screw 121Y pushes the reflecting mirror 45Y downward, and the lower surface of the reflecting mirror 45Y is pressed against the lower surface of the holder 52Y as shown in FIG. Thereby, the reflecting mirror 45Y is clamped and fixed to the holder 52Y by the lower surface of the holder 52Y and the screw 121Y. Also in the second embodiment, the second reflecting mirror 45Y is fixed to the holder 52Y, whereby the rigidity of the second reflecting mirror 45Y is increased and the vibration of the second reflecting mirror 45Y can be reduced. Further, the resonance frequency (natural frequency) of the second reflecting mirror 45Y can be separated from the low-frequency vibration propagated to the housing. As a result, the second reflecting mirror 45Y does not resonate with the low-frequency vibration propagated to the housing, and the vibration of the second reflecting mirror 45Y can be suppressed. Further, since the amplitude in the center in the longitudinal direction of the second reflecting mirror 45Y is the largest, the center of the reflecting mirror in the longitudinal direction is fixed to the holder 52Y with the screw 121Y and reinforced to thereby vibrate the second reflecting mirror 45Y. It can be effectively suppressed.

  In the above description, the screw 121Y is provided only at the center in the longitudinal direction of the upper surface of the holder, but a plurality of screws 121Y may be provided at equal intervals in the longitudinal direction of the upper surface of the holder. By fixing the second reflecting mirror 45Y to the holder 52Y with a plurality of screws, the fixing effect is enhanced and the vibration of the reflecting mirror can be further suppressed.

  Moreover, as shown in FIG. 17, you may affix the rubber sheet 122Y which is an elastic member on the lower surface of a holder. In the case of clamping and fixing with the screw 121Y, the vibration in the optical axis direction of the second reflecting mirror 45Y is suppressed by the frictional force between the lower surface of the holder 52Y and the lower surface of the reflecting mirror. By sticking the rubber sheet 122Y on the lower surface of the holder 52Y, when the second reflecting mirror 45Y is pushed downward by the screw 121Y, the lower surface of the second reflecting mirror 45Y comes into pressure contact with the rubber sheet 122Y. As a result, the frictional force can be improved and the fixing effect by the screw 121Y can be enhanced compared to when the lower surface of the large second reflecting mirror 45Y is pressed against the lower surface of the holder 52Y, and the second reflecting mirror 45Y can be further improved. Can be reduced.

FIG. 18 is an enlarged configuration diagram of a main part of the curvature correction mechanism according to the third embodiment.
The curvature correction mechanism according to the third embodiment uses an adhesive 130 to fix the second reflecting mirror 45Y to the lower surface of the holder 52Y.
As shown in FIG. 19, application holes 52dY for applying the adhesive 130 are formed at two locations on the surface of the holder 52Y facing the back surface of the second reflecting mirror 45Y. The application hole 52dY is formed between the longitudinal center and the end of the holder 52Y.

  After adjusting the curvature of the main scanning line, the adhesive 130 is applied to the gap between the lower surface of the holder and the lower surface of the second reflecting mirror 45Y from the coating hole 52dY, and the end portion and the central portion of the second reflecting mirror 45Y are applied. The gap is fixed to the holder 52Y. Also in the third embodiment, by fixing the second reflecting mirror 45Y to the holder 52Y, the rigidity of the second reflecting mirror 45Y can be increased, and the vibration of the reflecting mirror can be reduced (the amplitude during vibration can be suppressed). At the same time, the resonance frequency (natural frequency) of the second reflecting mirror 45Y can be increased. Thereby, the resonance frequency (natural frequency) of the second reflecting mirror 45Y can be separated from the low-frequency vibration propagated to the housing. As a result, the second reflecting mirror 45Y does not resonate with the low-frequency vibration propagated to the housing, and the vibration of the second reflecting mirror 45Y can be suppressed.

  Further, by applying the adhesive 130 from the application hole 52dY provided on the surface of the holder 52Y facing the back surface of the second reflecting mirror 45Y, compared to the case where the adhesive 130 is applied from the mirror surface side of the second reflecting mirror 45Y. Thus, the possibility that the mirror surface of the second reflecting mirror 45Y is soiled with the adhesive 130 can be reduced. Also, by fixing with the adhesive 130, when the second reflecting mirror 45Y is fixed to the holder 52Y as in the first and second embodiments, the second reflecting mirror 45Y is moved relative to the holder 52Y. It can be fixed without. Further, even if the flatness of the lower surface of the second reflecting mirror 45Y is somewhat poor, the second reflecting mirror 45Y can be firmly fixed to the holder 52Y.

  Further, an ultraviolet curable adhesive 130 ′ may be used as the adhesive 130. In this case, the ultraviolet curable adhesive 130 'is applied from the application hole 52dY to the gap between the lower surface of the second reflecting mirror 45Y before the curvature correction and the lower surface of the holder 52Y. Next, the curvature of the main scanning line is corrected. After executing the curve correction of the main scanning line, as shown in FIG. 20, the ultraviolet curable adhesive 130 'is irradiated with ultraviolet rays through the application hole 52dY. As a result, the ultraviolet curable adhesive 130 'is cured, and the second reflecting mirror 45Y is bonded and fixed to the holder 52Y. As shown in FIG. 20, the coating hole 52dY is enlarged so that the ultraviolet ray curable adhesive 130 'is reliably irradiated with the ultraviolet ray.

  Alternatively, a coating hole 52dY may be provided in the center of the holder, and the longitudinal center of the holder 52Y and the longitudinal center of the reflecting mirror 45Y may be fixed with an adhesive. As described above, the center of the reflecting mirror 45Y in the longitudinal direction has the largest amplitude. Therefore, by fixing the center of the reflecting mirror in the longitudinal direction to the holder 52Y with an adhesive, vibration of the second reflecting mirror 45Y can be effectively suppressed. Can be suppressed.

  By using an ultraviolet curable adhesive, the second reflecting mirror 45Y can be bonded and fixed to the holder 52Y simply by irradiating ultraviolet rays after correcting the curvature of the scanning line. Therefore, if the passage of light can be secured from outside the optical scanning device, it can be bonded and fixed. Has merit.

  As described above, the curvature correction mechanism of the present embodiment includes the laser diode as the light beam emitting means and the deflecting means (polygon mirrors 41a and 41b, a polygon motor (not shown) or the like for deflecting the light beam emitted from the laser diode in the main scanning direction. And a reflecting mirror that reflects the light beam, and is used in an optical scanning device that optically scans a photosensitive member that is a scanning object by the light beam. The curvature correction mechanism includes a holder 52Y as a holding body that holds the reflecting mirror, a support protrusion of the holder 52, and a leaf spring member 54, and pushes the reflecting mirror held in the holder 52Y in a direction perpendicular to the mirror surface. And a pressing device 64 that is a forced bending means for forcibly bending, and by adjusting the pressing amount by the pressing device 64, the curvature of the main scanning line on the surface of the photosensitive member is corrected. In the curvature correction mechanism having such a configuration, a fixing means for fixing the reflecting mirror in a state where the curvature of the main scanning line is corrected to the holder 52 is provided. As described above, since the reflecting mirror in a state where the curvature of the main scanning line is corrected is fixed to the holder 52 by the fixing means, the rigidity of the reflecting mirror can be increased by the holder, and the amplitude when the reflecting mirror vibrates is reduced. Is done. As a result, image degradation such as banding can be suppressed. Further, at the time of curvature correction, the reflector is merely held by the holder so that it can be bent, and is not fixed. Therefore, the rigidity of the reflector is low. Therefore, the reflecting mirror can be curved well, and the curvature of the main scanning line can be corrected well. In addition, since the reflector with the main scan line corrected for curvature is reinforced by the holder, there is no need to provide a reinforcing member between the holder and the reflector, and the size of the device and the reduction in layout margin are suppressed. can do. Furthermore, since the rigidity of the reflecting mirror can be increased without using a reinforcing member, an increase in the number of parts can be suppressed, and an increase in the cost of the apparatus can be suppressed.

  In addition, as shown in Example 1, the double-sided tape is used as the fixing means, and the reflective mirror is attached to the double-sided tape of the reflective mirror before the reflective mirror is fixed to the holding body by the double-sided tape. The holder is held so as to be movable in a direction orthogonal to the surface to be formed. With this configuration, the reflecting mirror can be pressed against the double-sided tape by moving the reflecting mirror after curvature correction in a direction perpendicular to the surface to which the double-sided tape of the reflecting mirror is attached. The mirror can be fixed to the holder with double-sided tape.

  Further, as shown in the second embodiment, as the fixing means, the screw 121 as a pressing member that presses the reflecting mirror against the holder is used, and the reflecting mirror in a state in which the curvature of the main scanning line is corrected is pressed against the holder with the screw. The reflecting mirror in a state where the curvature of the main scanning line is corrected may be fixed to the holding body.

  Furthermore, as shown in the second embodiment, an elastic sheet member may be attached to the surface of the holder on which the reflecting mirror is pressed. Accordingly, when the reflecting mirror is pressed against the holder with a screw, the reflecting mirror is pressed and fixed to the elastic member. As a result, the frictional force between the holder and the reflecting mirror is increased, and the reflecting mirror can be more firmly fixed to the holder.

  Moreover, as shown in Example 3, an adhesive may be used as the fixing means. By using an adhesive as the fixing means, the reflecting mirror 45Y is bonded and fixed to the holder 52Y. By fixing with the adhesive 130, when the reflecting mirror is fixed to the holder as in the first and second embodiments, the reflecting mirror can be fixed without moving relative to the holder. Moreover, even if the flatness of the surface fixed to the holder of the reflecting mirror is somewhat poor, the reflecting mirror can be firmly fixed to the holder.

  Moreover, you may use an ultraviolet curable adhesive as an adhesive agent. By using an ultraviolet curable adhesive, the reflecting mirror can be bonded and fixed to the holder simply by applying ultraviolet rays. For this reason, it is possible to bond and fix from the outside of the optical scanning device as long as the passage of light can be secured.

  Further, by providing the application hole 52d, which is a transmission part that transmits ultraviolet rays, in the holder, the ultraviolet rays can be favorably applied to the ultraviolet curable adhesive. By providing a transmission part that transmits ultraviolet rays, it is possible to increase the degree of freedom in the irradiation direction of ultraviolet rays.

  Further, a slow-acting double-sided tape may be used as the fixing means. By using a slow-acting double-sided tape, it is possible to perform curvature correction while the reflector is temporarily fixed to the holder with a slow-acting double-sided tape. There is no need to perform an operation of moving in a direction perpendicular to the surface to be formed. Therefore, the number of work steps can be reduced, leading to a reduction in manufacturing cost.

  Further, the upper or lower surface of the reflecting mirror, which is the longitudinal side surface of the reflecting mirror orthogonal to the mirror surface of the reflecting mirror, is fixed to the holder. Even when the reflecting mirror is curved, the upper surface or the lower surface of the reflecting mirror is a plane. Therefore, the reflecting mirror can be stably fixed to the holder.

4: Optical writing units 10Y, 10C, 10M, 10K: Photoconductor 44: First reflecting mirror 45: Second reflecting mirror 52: Holder 52a: Claw (supporting protrusion)
52b: leaf spring 52c: notch 52d: application hole 52f: adjustment screw mounting surface 64: pushing device 120: double-sided tape 121: screw 122: rubber sheet 130: adhesive

JP-A-10-282399 JP 2006-259368 A

Claims (14)

A light beam emitting means; a deflecting means for deflecting the light beam emitted from the light beam emitting means in a main scanning direction; and a reflecting mirror for reflecting the light beam. Used for scanning optical scanning device,
A holding body that holds the reflecting mirror so that it can be bent;
Forcibly bending means for forcibly bending the reflecting mirror held by the holding body by pushing it in a direction perpendicular to the mirror surface;
In a curvature correction mechanism that corrects the curvature of the main scanning line on the surface of the scanning object by adjusting the pushing amount by the forced bending means,
A bending correction mechanism comprising: a fixing means for fixing the reflecting mirror in a state in which the bending of the main scanning line is corrected to the holding body having higher rigidity than the reflecting mirror. In the curvature correction mechanism of claim 1,
The fixing means is a double-sided tape,
In a state before the reflecting mirror is fixed to the holding body by the double-sided tape, the reflecting mirror is movable to the holding body so as to be movable in a direction perpendicular to the surface to which the double-sided tape of the reflecting mirror is attached. A curvature correction mechanism that is held. In the curvature correction mechanism of claim 1,
The fixing means is a pressing member that presses the reflecting mirror against the holding body,
By pressing the reflecting mirror in a state where the curvature of the main scanning line is corrected by the pressing member against the holding body, the reflecting mirror in the state where the curvature of the main scanning line is corrected is fixed to the holding body. A characteristic curvature correction mechanism. In the curvature correction mechanism of claim 3,
A curvature correcting mechanism, wherein an elastic sheet member is attached to a surface of the holding body against which the reflecting mirror is pressed. In the curvature correction mechanism of claim 1,
A curvature correcting mechanism using an adhesive as the fixing means. In the curvature correction mechanism according to claim 5,
A curvature correcting mechanism using an ultraviolet curable adhesive as the adhesive. The curvature correction mechanism according to claim 6,
A curvature correcting mechanism, wherein the holder is provided with a transmission part through which the ultraviolet rays are transmitted. In the curvature correction mechanism of claim 1,
A curvature correction mechanism using a slow-acting double-sided tape as the fixing means. The curvature correction mechanism according to any one of claims 1 to 8,
A curvature correcting mechanism, wherein a longitudinal side surface of the reflecting mirror perpendicular to the mirror surface of the reflecting mirror is fixed to the holding body. A light beam emitting means; a deflecting means for deflecting the light beam emitted from the light beam emitting means in a main scanning direction; a reflecting mirror for reflecting the light beam; and a curve of the main scanning line on the surface of the scanning object. And an optical scanning device that optically scans the scanning object with the light beam.
An optical scanning apparatus using the curvature correction mechanism according to claim 1 as the curvature correction means. A latent image carrier that carries a latent image, an optical scanning unit that forms a latent image on the surface of the latent image carrier by optical scanning, and a developing unit that develops the latent image carried on the latent image carrier. In the image forming apparatus provided,
An image forming apparatus using the optical scanning device according to claim 10 as the optical scanning unit. Light beam launching means;
Deflecting means for deflecting the light beam emitted from the light beam emitting means in the main scanning direction;
A reflecting mirror for reflecting the light beam;
Bending correction that includes a forcibly bending means for forcibly bending the reflecting mirror by pushing it in a direction perpendicular to the mirror surface, and correcting the bending of the main scanning line on the surface of the scanning object by adjusting the amount of pushing by the forcibly bending means. And a method of manufacturing an optical scanning device that optically scans the scanning object with the light beam,
After correcting the curvature of the main scanning line by the curvature correcting means, there is a step of fixing the reflecting mirror after correcting the curvature of the main scanning line to a holding body that holds the reflecting mirror with a double-sided tape. Manufacturing method of optical scanning device. Light beam launching means;
Deflecting means for deflecting the light beam emitted from the light beam emitting means in the main scanning direction;
A reflecting mirror for reflecting the light beam;
Bending correction that includes a forcibly bending means for forcibly bending the reflecting mirror by pushing it in a direction perpendicular to the mirror surface, and correcting the bending of the main scanning line on the surface of the scanning object by adjusting the amount of pushing by the forcibly bending means. And a method of manufacturing an optical scanning device that optically scans the scanning object with the light beam,
After correcting the curvature of the main scanning line by the curvature correcting means, the process includes a step of pressing and fixing the reflecting mirror after correcting the curvature of the main scanning line to a holding body holding the reflecting mirror by a pressing member. A method for manufacturing an optical scanning device. Light beam launching means;
Deflecting means for deflecting the light beam emitted from the light beam emitting means in the main scanning direction;
A reflecting mirror for reflecting the light beam;
Bending correction that includes a forcibly bending means for forcibly bending the reflecting mirror by pushing it in a direction perpendicular to the mirror surface, and correcting the bending of the main scanning line on the surface of the scanning object by adjusting the amount of pushing by the forcibly bending means. And a method of manufacturing an optical scanning device that optically scans the scanning object with the light beam,
After correcting the curvature of the main scanning line by the curvature correcting means, there is a step of fixing the reflecting mirror after correcting the curvature of the main scanning line to a holding body that holds the reflecting mirror with an adhesive. Manufacturing method of optical scanning device.

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