JP5863438B2 - Optical scanning device and image forming apparatus having the same - Google Patents

Description

  The present invention is an optical scanning device applicable to an image forming apparatus such as a digital copying machine, a laser printer, or a facsimile machine, and in particular, is arranged between a deflector that deflects and scans light from a light source onto a scanned object. The present invention relates to an optical scanning device configured to adjust a rotation angle around a height axis along a height direction orthogonal to a longitudinal direction of a long optical member provided, and an image forming apparatus including the same.

  A light source, a deflector (for example, a rotary polygon mirror) that deflects and scans light from the light source onto a scanned object, and a long optical member disposed between the deflector and the scanned object (for example, a photosensitive drum) In a conventional optical scanning device including an optical lens (for example, an optical lens), an optical device in a rotating direction in which the optical member rotates about a height axis along a height direction orthogonal to the longitudinal direction of the optical member by an adjustment mechanism. It is known to adjust the rotation angle of a member (see Patent Document 1).

JP 2010-8761 A

  However, in the conventional optical scanning device as described in Patent Document 1, the optical member is inclined around the longitudinal axis along the longitudinal direction when adjusting the rotation angle around the height axis of the optical member. In this case, inconvenience occurs due to the inclination of the optical member around the longitudinal axis. For example, an optical member (for example, an optical lens) does not theoretically have a light transmittance of 100%, and a considerable amount of reflected light is generated. Depending on the degree of inclination around the longitudinal axis of the optical member, the light from the deflector is scanned. In some cases, stray light, which is specularly reflected light from the surface, may be generated. In this case, in the image forming apparatus including the optical scanning device, an image defect is caused by stray light.

  Accordingly, the present invention provides a height along a height direction perpendicular to the longitudinal direction of a long optical member disposed between a deflector that scans and deflects light from a light source onto the scan target. An optical scanning device configured to adjust a rotation angle around a longitudinal axis, and a longitudinal axis along the longitudinal direction of the optical member when adjusting the rotation angle around the height axis of the optical member It is an object of the present invention to provide an optical scanning device capable of suppressing the rotation inclination and an image forming apparatus including the same.

In order to solve the above problems, the present invention provides a light source, a deflector that deflects and scans light from the light source onto a scanned object, and a long length disposed between the deflector and the scanned object. An optical member, and an adjustment mechanism for adjusting a rotation angle of the optical member in a rotation direction in which the optical member rotates about a height axis along a height direction orthogonal to the longitudinal direction of the optical member; The adjusting mechanism includes a restricting member that restricts an inclination of the optical member around the longitudinal axis along the longitudinal direction , and the adjusting mechanism holds the optical member. And a holder member that is rotatable about a rotation shaft along the height direction, and an end face on one side in the width direction perpendicular to both the longitudinal direction and the height direction of the holder member Against the other side of the width direction against A pressing member that rotates the holder member with the rotation shaft as the rotation fulcrum, and the restricting member protrudes on one side in the width direction of the holder member, and the longitudinal length of the optical member An optical scanning device is provided that is configured to abut against the pressing member when regulating the inclination around the direction axis . The present invention also provides an image forming apparatus comprising the optical scanning device according to the present invention.

  According to the present invention, when adjusting the rotation angle of the optical member around the height axis of the optical member by the adjusting mechanism, the inclination of the optical member around the longitudinal axis of the optical member is regulated by the regulating member. This makes it possible to suppress the inclination of the optical member around the longitudinal axis.

In addition , the restriction member protrudes from one side of the holder member in the width direction, and abuts against the pressing member when restricting the inclination of the optical member around the longitudinal axis. In addition, the inclination of the optical member around the longitudinal axis can be restricted by the restriction member.

  In the present invention, the restriction member can be exemplified as an aspect provided on one side in the height direction of the holder member with respect to the pressing member.

  In this specific matter, the tilting of the optical member toward the other side in the height direction may be regulated by the regulating member provided on the one side in the height direction of the holder member with respect to the pressing member. it can.

  In the present invention, the adjustment mechanism includes a guide member positioned on one side of the holder member in the height direction, and the restriction member is provided between the guide member and the pressing member. It can be illustrated.

  In this specific matter, the restriction member provided between the guide member and the pressing member located on one side of the holder member in the height direction causes one side of the optical member in the height direction and The inclination to the other side can be regulated.

  In the present invention, the holder member includes a holder main body that holds the optical member, and a connecting member that is connected to one end face in the width direction of the holder main body, and the adjustment mechanism is connected to the connecting member. It is set as the structure which presses the said pressing member with respect to it, The said control member can illustrate the aspect provided in the said connection member.

  In this specific matter, since the restriction member is provided on the connecting member, it is possible to reliably suppress the inclination of the optical member around the longitudinal axis.

  In the present invention, the connecting member is a long member extending in the width direction, and the adjusting mechanism is configured to push the pressing member against the end face on one side in the width direction of the connecting member. The aspect made into the structure pressed toward the other side of a direction can be illustrated.

  In this specific matter, the adjustment mechanism is configured to press the pressing member toward the other side in the width direction against the end surface on one side in the width direction in the long connecting member extending in the width direction. Thus, the pressing member can be stably pressed against the connecting member.

  In this invention, the said adjustment mechanism can illustrate the aspect by which the virtual straight line along the direction of the force which presses the said pressing member with respect to the said holder member crosses the said longitudinal direction axis line of the said optical member.

  In this specific matter, the adjustment mechanism is configured such that the imaginary straight line along the direction of the force pressing the pressing member against the holder member intersects the longitudinal axis of the optical member. It is possible to reliably suppress the inclination of the optical member around the longitudinal axis.

  In the present invention, the restriction member is provided on an end surface of the holder member on one side in the width direction, and has a concave portion extending along the width direction, and the adjustment mechanism includes the holder member. On the other hand, it is possible to exemplify a mode in which the pressing member is pressed in the concave portion.

  In this specific matter, it is possible to press the pressing member against the holder member in a state where the pressing member avoids interference with the regulating member while maintaining the strength of the regulating member.

  In the present invention, the pressing member has a shaft portion provided with a male screw portion, and the adjustment mechanism is provided with a female screw portion that is screwed to the male screw portion to support the shaft portion along the width direction. The aspect provided with the axis | shaft support part which rotates and the rotation mechanism which rotates the said axis | shaft part can be illustrated.

  In this specific matter, the shaft portion is rotated around the axis by the rotating mechanism in a state where the male screw portion in the shaft portion is screwed with the female screw portion in the shaft support portion, although the configuration is simple. It can be rotated to the other side or the other side, and can be moved to one side or the other side in the width direction. Thereby, the rotation angle of the optical member around the height axis can be adjusted according to the rotation amount of the shaft portion.

  In the present invention, the rotation mechanism includes a first gear having the shaft portion as a rotation axis, a second gear meshing with the first gear with an axis orthogonal to the rotation axis of the first gear as the rotation axis, A mode provided with the drive part which rotationally drives the 2nd gear can be illustrated.

  In this specific matter, the second gear that meshes with the first gear can be rotationally driven by the drive unit with an axis orthogonal to the rotational axis of the first gear as a rotational axis.

  In this invention, the said rotation fulcrum can illustrate the aspect provided in the one side edge part of the said longitudinal direction.

  In this specific matter, the rotation radius of the optical member around the rotation fulcrum can be increased as compared with the case where the rotation fulcrum is provided at the central portion in the longitudinal direction, and the height of the optical member is increased accordingly. It becomes possible to facilitate fine adjustment of the rotation angle around the vertical axis.

  In the present invention, the adjusting mechanism includes an urging portion configured to urge the holder member toward the pressing member in a state where the holder member is urged so as to be regulated in the height direction. it can.

  In this specific matter, the biasing portion can bias the optical member against the pressing force by the pressing member in a state of being biased so as to regulate the holder member in the height direction. As a result, even if the pressing member is displaced to one side in the width direction, the pressing member is kept in the state of the optical member with respect to the one side in the width direction while suppressing the inclination of the optical member around the longitudinal axis. The rotation angle around the height direction axis can be easily adjusted.

  In the present invention, the optical member may be a plurality of optical members disposed between the deflector and the scanned object, and the adjustment mechanism may be configured such that the plurality of optical members around the height direction axis. A plurality of adjusting mechanisms that respectively adjust rotation angles of the plurality of optical members in a rotation direction in which the members rotate; and the regulating member is configured to tilt the plurality of optical members around the longitudinal axis. The aspect made into the some control member which controls each can be illustrated.

  This specific matter can be applied to a color optical scanning device.

  As described above, according to the optical scanning device and the image forming apparatus including the same according to the present invention, it is possible to suppress the inclination of the optical member around the longitudinal axis.

1 is a schematic cross-sectional view of an entire configuration of an image forming apparatus according to an embodiment viewed from the front. 2 is a system block diagram of a control system that controls main components in the image forming apparatus according to the present embodiment. FIG. FIGS. 2A and 2B are views showing the exposure unit shown in FIG. 1 together with the positional relationship with the photosensitive drum, in which FIG. 1A is a schematic plan view of the exposure unit, and FIG. 1B is a schematic side view of the exposure unit. It is a schematic perspective view which shows the arrangement structure of the 2nd f (theta) lens in an exposure unit. It is a principal part expansion perspective view which mainly shows the adjustment unit and 2nd f (theta) lens part in the automatic adjustment mechanism of an exposure unit. It is the sectional view on the AA line shown in FIG. It is a schematic block diagram which shows typically the adjustment unit shown in FIG. It is a principal part expansion perspective view which mainly shows the adjustment unit and 2nd f (theta) lens part in the manual adjustment mechanism of an exposure unit. It is the BB sectional view taken on the line shown in FIG. It is a schematic block diagram which shows typically the adjustment unit shown in FIG.

  Embodiments according to the present invention will be described below with reference to the drawings. The following embodiment is an example embodying the present invention, and does not limit the technical scope of the present invention.

  FIG. 1 is a schematic cross-sectional view of the entire configuration of the image forming apparatus 100 according to the present embodiment as viewed from the front.

  An image forming apparatus 100 shown in FIG. 1 forms an image composed of at least one color (a plurality of colors or a single color) on a sheet such as a recording sheet (hereinafter referred to as a recording sheet) in accordance with image data for image formation. A color image forming apparatus.

  The image forming apparatus 100 forms an image on a recording sheet by an electrophotographic method, and is a multi-function machine having a copy mode, a facsimile mode, a document filing mode, a mail mode, and a network printer mode as operation modes.

  The image forming apparatus 100 includes a document reading device 108, an apparatus main body 110, and an input operation unit 400 (see FIG. 2 described later). The apparatus main body 110 is provided with an image forming unit 102 and a paper conveyance system 103. . The image forming unit 102 forms (prints) an image on a recording sheet based on image data output from the document reading device 108 or image data received from the outside.

  The image forming unit 102 includes an exposure unit 1 (an example of an optical scanning device), a plurality of developing units 2-2, a plurality of photosensitive units 4-4, an intermediate transfer belt unit 6, a pre-transfer charging unit 8, and a plurality of toner cartridges. Units 21 to 21 and a fixing unit 7 are provided. The paper transport system 103 includes a paper feed tray 81, a manual paper feed tray 82, and a paper discharge tray 91.

  An upper part of the apparatus main body 110 is provided with an original placing table 92 made of transparent glass on which a sheet of an original or the like (hereinafter referred to as an original) is placed. An optical unit that reads an image of the original is placed below the original placing base 92. 90 is provided. The optical unit 90 is a color scanner that reads an image of a document placed on the document placement table 92 or reads an image of a document conveyed by the document reading device 108. A document reading device 108 is provided above the document placing table 92. The document reading device 108 automatically conveys a document on the document placing table 92. Further, the document reading device 108 is attached to the apparatus main body 110 so as to be pivotable by opening the front side, and the document can be placed manually by opening the document placing table 92. . In the present embodiment, the front side of the apparatus main body 110 is the front side (the operation side operated by the user).

  The document reading device 108 can automatically read a document that is automatically transported onto the document placement table 92 or an image of a document placed on the document placement table 92. The entire original image read by the original reading device 108 is sent to the apparatus main body 110 as image data, and an image formed based on the image data in the apparatus main body 110 is recorded on a recording sheet.

  The image data handled in the image forming apparatus 100 corresponds to a color image using a plurality of colors (here, black (K), cyan (C), magenta (M), and yellow (Y)). Accordingly, the developing unit 2, the photosensitive unit 4, and the toner cartridge unit 21 are each provided with a plurality (four in this case) so as to form a plurality of types (four types in this case) corresponding to the respective colors. , Cyan, magenta, and yellow), and these constitute an image station for each color (here, four).

  In the photoreceptor units 4 to 4, the chargers 5 to 5 are charging means for uniformly charging the surfaces of the photoreceptor drums 3 to 3 to a predetermined potential.

  The exposure unit 1 is configured as a laser scanning unit (LSU) including a laser emitting unit and a reflection mirror, and deflects and scans the photosensitive drums 3 to 3. The exposure unit 1 will be described in detail later.

  The toner cartridge units 21 to 21 are units for storing toner, and the toner is supplied to the developing tanks of the developing units 2 and 2.

  The developing units 2 to 2 visualize the electrostatic latent images formed on the photosensitive drums 3 to 3 with toners of four colors (Y, M, C, and K). The photosensitive units 4 to 4 also have a cleaning function for removing and collecting toner remaining on the surfaces of the photosensitive drums 3 and 3 after development and image transfer.

  The intermediate transfer belt unit 6 disposed above the photosensitive drums 3 to 3 includes an intermediate transfer belt 61 that acts as an intermediate transfer member, a driving roller 62, a driven roller 63, a plurality of intermediate transfer rollers 64 to 64, and a cleaning unit. 65.

  The intermediate transfer rollers 64 to 64 are provided corresponding to each color of Y, M, C, and K. The drive roller 62 stretches and rotates the intermediate transfer belt 61 together with the driven roller 63 and the intermediate transfer roller 64, so that the intermediate transfer belt 61 rotates in the moving direction (in the direction of arrow M in FIG. 1). Accordingly, the driven roller 63 and the intermediate transfer rollers 64 to 64 are driven to rotate.

  A transfer bias for transferring the toner image formed on the photosensitive drums 3 to 3 onto the intermediate transfer belt 61 is applied to each of the intermediate transfer rollers 64 to 64.

  The intermediate transfer belt 61 is provided so as to be in contact with each of the photosensitive drums 3 to 3. The intermediate transfer belt 61 sequentially superimposes and transfers the toner images of the respective colors formed on the photosensitive drums 3 to 3 to form a color toner image (multicolor toner image) on the surface.

  Transfer of the toner image from the photosensitive drums 3 to 3 to the intermediate transfer belt 61 is performed by intermediate transfer rollers 64 to 64 that are in contact with the back side of the intermediate transfer belt 61. A high voltage transfer bias is applied to the intermediate transfer rollers 64 to 64 in order to transfer the toner image.

  The toner images visualized according to the hues on the photosensitive drums 3 to 3 are stacked on the intermediate transfer belt 61. The toner images stacked on the intermediate transfer belt 61 are recorded by the transfer roller 10 constituting the secondary transfer mechanism unit disposed at the contact position between the recording paper and the intermediate transfer belt 61 by the circumferential movement of the intermediate transfer belt 61. Transferred onto paper.

  When the toner image is transferred from the intermediate transfer belt 61 onto the recording paper by the transfer roller 10, the toner remaining on the intermediate transfer belt 61 without being transferred onto the recording paper is removed and collected by the cleaning unit 65.

  Here, the pre-transfer charging unit 8 has a pre-transfer charger (PTC), and is upstream of the transfer nip between the transfer roller 10 and the intermediate transfer belt 61 in the moving direction M of the intermediate transfer belt 61. The toner image before being transferred to the recording paper in the vicinity is uniformly charged.

  The paper feed tray 81 is a tray that previously stores recording paper on which an image is formed (printed), and is provided below the exposure unit 1 in the apparatus main body 110. In addition, a recording paper on which an image is formed (printed) is placed on the manual paper feed tray 82. The paper discharge tray 91 is provided above the image forming unit 102 in the apparatus main body 110 and stacks recording sheets on which image formation (printing) has been performed face-down.

  Further, the apparatus main body 110 is provided with a paper conveyance path S for sending the recording paper sent from the paper feed tray 81 and the manual paper feed tray 82 to the paper discharge tray 91 through the transfer roller 10 and the fixing unit 7. It has been. In the vicinity of the sheet conveyance path S, pickup rollers 11a and 11b, a plurality of conveyance rollers 12a to 12d, a registration roller 13, a transfer roller 10, and a heat roller 71 and a pressure roller 72 in the fixing unit 7 are arranged.

  The conveyance rollers 12 a to 12 d are small rollers for promoting and assisting the conveyance of the recording paper, and are provided along the paper conveyance path S. Further, the pickup roller 11 a picks up the recording paper one by one from the paper feed tray 81 and supplies it to the paper transport path S. Similarly, the pickup roller 11b picks up recording sheets one by one from the manual sheet feeding tray 82 and supplies the recording sheets to the sheet conveyance path S.

  The registration roller 13 temporarily holds the recording paper conveyed through the paper conveyance path S. Then, the registration roller 13 conveys the recording paper to the transfer roller 10 at a timing when the leading edge of the toner image on the photosensitive drums 3 to 3 is aligned with the leading edge of the recording paper.

  The fixing unit 7 fixes an unfixed toner image on a recording sheet, and includes a heat roller 71 and a pressure roller 72 that act as a fixing roller. The heat roller 71 is provided with a heater 71a on the inner side, and is driven to rotate so as to convey the recording paper while sandwiching the recording paper together with the pressure roller 72 that is driven to rotate. The heat roller 71 is maintained at a predetermined fixing temperature based on a signal from the temperature detector 71b. Further, the fixing unit 7 includes an external heating belt 73 that heats the heat roller 71 from the outside.

  In the image forming apparatus 100 configured as described above, when single-sided printing is requested as a recording sheet, the recording sheet supplied from the sheet feeding tray 81 or the manual sheet feeding tray 82 is provided along the sheet conveying path S. Then, the toner is conveyed to the registration roller 13 by the conveyed roller 12a and conveyed by the transfer roller 10 at a timing when the leading edge of the recording paper and the leading edge of the toner image on the intermediate transfer belt 61 are aligned, and the toner image is transferred onto the recording paper. . Thereafter, the recording sheet passes through the fixing unit 7, whereby unfixed toner on the recording sheet is melted and fixed by heat, and is discharged onto the sheet discharge tray 91 through the conveyance roller 12 b.

  When double-sided printing is requested for the recording paper, the trailing edge of the recording paper that has passed the fixing unit 7 after completion of the above-described single-sided printing is the final transport roller 12b and the branch portion Sa of the paper transport path S. The recording paper is guided to the conveyance rollers 12c and 12d by the reverse rotation of the conveyance roller 12b in the state of being positioned between the two. Then, the recording paper conveyed to the transfer nip via the registration roller 13 is printed on the back surface and then discharged to the paper discharge tray 91.

  FIG. 2 is a system block diagram of a control system that controls main components in the image forming apparatus 100 according to the present embodiment.

  The image forming apparatus 100 according to the present embodiment includes a main control unit 300 that controls the entire image forming apparatus 100, an input operation unit 400 including an input unit 301 and a display unit 302, and various types of information such as image data. A storage unit 303 that stores data, an image processing calculation unit 304 that performs calculation of image processing on image data, a network interface (I / F) 306 that is connected to the outside via the network 305, and an optical unit 90 that reads an image of a document. And an image forming unit 102 that forms an image on recording paper based on the image data, and a facsimile unit 308 that is connected to the outside via a telephone line 307, and these constituent members are connected to the image data via a bus 309. (Signal) is connected in a state where transmission / reception is possible.

  The main control unit 300 is a processing unit such as a CPU (Central Processing Unit). The seed control unit 300 is connected to the input operation unit 400, the storage unit 303, the image processing calculation unit 304, the network interface 306, the optical unit 90, the image forming unit 102, and the facsimile unit 308. For example, the main control unit 300 causes the image forming unit 102 to execute a printing process (image forming process) based on image data received through the network interface 306.

  The input unit 301 receives input data of an input operation by a user. The display unit 302 displays operation information for each operation mode as arbitrary display data including operation information. The storage unit 303 includes a ROM (Read Only Memory), a RAM (Random Access Memory), and a rewritable nonvolatile memory.

  Next, the exposure unit 1 which is an example of the optical scanning device according to the present invention will be described in detail.

[About exposure unit]
FIG. 3 is a view showing the exposure unit 1 shown in FIG. 1 together with the positional relationship with the photosensitive drums 3 to 3. FIG. 3A shows a schematic plan view of the exposure unit 1, and FIG. 3B shows a schematic side view of the exposure unit 1. In FIG. 3 and FIGS. 4 to 10 described later, members having substantially the same configuration are denoted by the same reference numerals.

  The exposure unit 1 sensitizes a laser beam from a plurality of (here, four) laser emitting units 30 to 30 (an example of a light source) corresponding to each color via an optical system including a rotating polygon mirror 35 (an example of a deflector). It is configured as a laser scanning unit (LSU) that emits to the body drums 3 to 3 (see FIG. 1).

  The exposure unit 1 exposes the charged photosensitive drums 3 to 3 according to the image data, respectively, so that an electrostatic latent image corresponding to the image data is displayed on the surface (scanning surface) of each of the photosensitive drums 3 to 3. To form.

Various optical components are provided on the optical path from the laser emitting units 30 to 30 to the photosensitive drums 3 to 3. Specifically, a plurality (four in this case) of collimating lenses 31 to 31, a plurality of (here four) first reflecting mirrors 32 to 32, a cylindrical lens 33, and a second one from the laser emitting units 30 to 30 side. The reflection mirror 34, the rotary polygon mirror 35, the first fθ lens 36, the folding mirrors 341 to 341, and a plurality (four in this case) of second fθ lenses 37 to 37 (an example of an optical member) are sequentially arranged in the housing 1a. Yes.

The laser emitting units 30 to 30 are provided at predetermined locations of the housing 1a, and serve as beam emitting means for emitting laser beams modulated corresponding to the respective colors. In FIG. 3B, the laser emitting units 30 to 30 are not shown.

  The collimating lenses 31 to 31 are provided in the housing 1a corresponding to the laser emitting units 30 to 30, respectively, and are configured to convert the laser beams emitted from the laser emitting units 30 to 30 into parallel beams.

  The first reflecting mirrors 32 to 32 are provided in the housing 1 a corresponding to the collimating lenses 31 to 31, respectively, and reflect the laser beam converted by the collimating lenses 31 to 31 so as to be incident on the cylindrical lens 33. Yes.

  The cylindrical lens 33 is configured to focus a plurality of (here, four) laser beams incident from a plurality (here, four) first reflecting mirrors 32 to 32 on the photosensitive drums 3 to 3 in the sub-scanning direction. It is said that. The cylindrical lens 33 is configured such that the incident laser beam is made into parallel light as it is in the main scanning direction and converges at the center of the reflecting surface 35a of the rotary polygon mirror 35 in the sub-scanning direction.

  The second reflecting mirror 34 is configured to reflect a plurality (four in this case) of laser beams emitted from the cylindrical lens 33 and to enter the rotary polygon mirror 35.

  The rotary polygon mirror 35 is configured to deflect and scan the laser beam reflected by the central region in the height direction of the reflection surface with respect to the photosensitive drums 3 to 3 by being driven to rotate at a constant rotation speed.

  The first fθ lens 36 converges the parallel light reflected by the rotary polygon mirror 35 in the main scanning direction so as to have a predetermined beam diameter on the surface of the photosensitive drums 3 to 3, and in the sub scanning direction, the rotary polygon mirror 35. The diffused light reflected by the light is converted into parallel light. The first fθ lens 36 moves the laser beam moving at a constant angular velocity in the main scanning direction by the constant angular velocity movement of the rotary polygon mirror 35 on the scanning lines on the photosensitive drums 3 to 3 at a constant linear velocity. It has the function to convert.

  The folding mirrors 341 to 341 are configured to guide the laser beam that has passed through the first fθ lens 36 to the second fθ lenses 37 to 37.

  The second fθ lenses 37 to 37 have a convex lens surface (not shown) protruding toward the exit surface side, and are made of, for example, polycarbonate resin. The second fθ lenses 37 to 37 are long lenses that are long in the main scanning direction. The second fθ lenses 37 to 37 converge the laser beam incident as parallel light in the sub-scanning direction so as to have a predetermined beam diameter on the photosensitive drums 3 to 3, and the first fθ lens 36 in the main scanning direction. The converged laser beam is converged on the photosensitive drums 3 to 3 as they are.

  The exposure unit 1 according to the present embodiment includes laser emitting units 30 to 30, and a rotary polygon mirror 35 that deflects and scans light from the laser emitting units 30 to 30 to the photosensitive drums 3 to 3 (an example of a scanning target). The second fθ lenses 37 to 37 disposed on the optical path between the rotary polygon mirror 35 and the photosensitive drums 3 to 3, and the irradiation of the laser beam irradiated to the photosensitive drums 3 to 3 from the second fθ lenses 37 to 37. Adjustment units 40 to 40 (see FIG. 4 described later) configured to adjust the position are provided.

  FIG. 4 is a schematic perspective view showing the arrangement configuration of the second fθ lenses 37 to 37 in the exposure unit 1.

  The adjustment units 40 to 40 are arranged around a height direction axis δ to δ along a height direction (arrow Z direction in the figure) orthogonal to the longitudinal direction (arrow X direction in the figure) of the second fθ lenses 37 to 37 ( Longitudinal axes α1 to αn along the longitudinal direction X of the second fθ lenses 37 to 37 in the rotation directions C to C in which the second fθ lenses 37 to 37 rotate (here, the protrusions 1b to 1b are the rotation axes). Here, adjustment mechanisms 50 to 50 for adjusting rotation angles φ1 to φn (n is an integer of 2 or more, here n = 4) with respect to the reference virtual straight lines γ to γ of n = 4) are provided. Here, the reference virtual straight lines γ to γ are virtual straight lines along the main scanning direction in which the laser beam is scanned by the rotary polygon mirror 35. The adjustment range of the rotation angles φ1 to φ4 of the second fθ lenses 37 to 37 by the adjustment mechanisms 50 to 50 is not limited thereto, but can be about 2 ° to 3 °.

  In addition, in FIG. 4, the member which is not demonstrated above among the members which attach | subject the code | symbol is demonstrated later.

  The exposure unit 1 according to the present embodiment includes both an automatic adjustment mechanism 10a and a manual adjustment mechanism 10b. Specifically, the exposure unit 1 includes an automatic adjustment mechanism for a part (here, two) of the second (here, two) second fθ lenses 37, 37. 10 a is provided, and a manual adjustment mechanism 10 b is provided for the remaining (here, two) second fθ lenses 37 and 37. In the present embodiment, the exposure unit 1 includes both the automatic adjustment mechanism 10a and the manual adjustment mechanism 10b, but includes only one of the automatic adjustment mechanism 10a and the manual adjustment mechanism 10b. May be.

  Hereinafter, the automatic adjustment mechanism 10a and the manual adjustment mechanism 10b will be described separately for the adjustment mechanism of the exposure unit 1.

(Automatic adjustment mechanism)
FIG. 5 is an enlarged perspective view of a main part mainly showing the adjustment units 40 to 40 and the second fθ lenses 37 to 37 in the automatic adjustment mechanism 10 a of the exposure unit 1. 6 is a cross-sectional view taken along line AA shown in FIG. FIG. 7 is a schematic configuration diagram schematically illustrating the adjustment units 40 to 40 illustrated in FIG. 6. In addition, since the structure of each adjustment unit 40-40 is substantially the same, it has shown in one figure in FIGS. 5-7. The same applies to FIGS. 8 to 10 described later.

  The adjustment mechanisms 50 to 50 include restriction members 70 to 70 that restrict the inclinations of the 2fθ lenses 37 to 37 around the longitudinal axes α1 to α4 along the longitudinal direction X.

  In the present embodiment, the adjustment mechanisms 50 to 50 include holder members 41 to 41 and pressing members 60 to 60.

  The holder members 41 to 41 hold the second fθ lenses 37 to 37, and rotate the rotating shaft (specifically, the projecting portions 1 b to 1 b) along the height direction Z (specifically, the vertical direction). A movable fulcrum (see FIG. 4) is rotatable. The pressing members 60 to 60 are in the width direction with respect to the end surfaces 41a to 41a on one side Y1 in the width direction (arrow Y direction in the drawing) orthogonal to both the longitudinal direction X and the height direction Z in the holder members 41 to 41. The holder members 41 to 41 are rotated by pressing the projections 1b to 1b toward the rotation fulcrum by pressing toward the other side Y2 of Y.

  Specifically, the regulating members 70 to 70 are provided to protrude on one side Y1 in the width direction Y of the holder members 41 to 41, and regulate the inclination of the second fθ lenses 37 to 37 around the longitudinal axes α1 to α4. Further, the pressing members 60 to 60 are in contact with each other. The restricting members 70 to 70 may be provided on the holder members 41 to 41 in contact with the pressing members 60.

  The regulating members 70 to 70 are provided on one side Z1 (here, the lower side) of the holder members 41 to 41 in the height direction Z with respect to the pressing members 60 to 60.

  In the present embodiment, the adjusting mechanisms 50 to 50 are guide members 59 to 59 located on one side Z1 (here, the lower side) in the height direction Z of the holder members 41 to 41 (here, a connecting member 412 described later). It has. Specifically, the guide members 59 to 59 have a facing surface 59a that faces at least one of the regulating members 70 to 70 and the holder members 41 to 41 (here, the holder members 41 to 41), and the facing surface 59a is regulated. The casing 1a is provided so as to face at least one of the members 70 to 70 and the holder members 41 to 41 (here, the holder members 41 to 41). Specifically, the guide members 59 to 59 are formed integrally with the bottom surface of the housing 1a.

  The regulating members 70 to 70 are provided between the guide members 59 to 59 and the pressing members 60 to 60, and regulate the inclination of the second fθ lenses 37 to 37 around the longitudinal axes α1 to α4. The guide members 59 to 59 are in contact with each other.

  Here, the regulating members 70 to 70 are in a state where the second fθ lenses 37 to 37 are not inclined around the longitudinal axis α1 to α4 (a state where the pressing members 60 to 60 are not pressed against the holder members 41 to 41). The guide members 59 to 59 are in contact with or non-contact (here, non-contact). When the regulating members 70 to 70 are not in contact with the guide members 59 to 59, the gap d1 (see FIG. 7) between the regulating members 70 to 70 and the guide member 59 can be exemplified as 0 to 0.2 mm.

  Further, the regulating members 70 to 70 are in contact with or not in contact with the pressing members 60 to 60 (in this case, non-contact) in a state where the second fθ lenses 37 to 37 are not inclined around the longitudinal axis α1 to α4. . When the regulating members 70 to 70 are not in contact with the pressing members 60 to 60, the gap d2 (see FIG. 7) between the regulating members 70 to 70 and the pressing members 60 to 60 can be exemplified by about 0.3 mm. .

  In the present embodiment, the holder members 41 to 41 include holder main bodies 411 to 411 that hold the second fθ lenses 37 to 37, and other end portions 48 to 48 in the longitudinal direction X of the holder main bodies 411 to 411 (see FIG. 4). , Connecting members 412 to 412 connected to end surfaces 41b to 41b on one side Y1 in the width direction Y are provided. The adjustment mechanisms 50 to 50 are configured to press the pressing members 60 to 60 against the connecting members 412 to 412. The regulating members 70 to 70 are provided on the connecting members 412 to 412. Here, the connecting members 412 to 412 are fixed to the holder main bodies 411 to 411 by detachable fixing members such as screws. Specifically, the holder main bodies 411 to 411 are provided with female screws 411a to 411a. The connection members 412 to 412 are provided with attachment portions 412a to 412a having through holes 412b to 412b. The connecting members 412 to 412 are fixed to the holder main bodies 411 to 411 by the male screws SC being screwed into the female screws 411 a to 411 a in the holder main bodies 411 to 411 through the through holes 412 b to 412 b of the attachment portions 412 a to 412 a. It is like that.

  Further, the regulating members 70 to 70 are formed integrally with the connecting members 412 to 412. Here, the connecting members 412 to 412 and the regulating members 70 to 70 are made of a resin material. Specifically, the connecting members 412 to 412 and the regulating members 70 to 70 are formed in an L shape when viewed from the longitudinal direction X at one end Y1 in the width direction Y. Specifically, the connecting members 412 to 412 and the regulating members 70 to 70 have protruding portions constituting the L-shaped portions as the regulating members 70 to 70. That is, the restricting members 70 to 70 protrude from the end surface 41a on the one side Y1 in the width direction Y to the one side Y1 in the width direction Y at the end on the one side Z1 in the height direction Z (here, the lower side).

  In the present embodiment, the connecting members 412 to 412 are long members extending in the width direction Y. The adjustment mechanisms 50 to 50 are configured to press the pressing members 60 to 60 toward the other side Y2 in the width direction Y against the end faces 41a to 41a on the one side Y1 in the width direction Y of the connecting members 412 to 412. .

  Specifically, the adjustment mechanisms 50 to 50 are configured to press the pressing members 60 to 60 against the holder members 41 to 41 toward the longitudinal axes α1 to α4 of the second fθ lenses 37 to 37. Specifically, an imaginary straight line (more specifically, a rotation axis of a shaft 53 described later) β (see FIG. 5) along the direction of the force pressing the holder members 41 to 41 by the pressing members 60 to 60 is the second fθ. It intersects the longitudinal axes α1 to α4 of the lenses 37 to 37.

  The regulating members 70 to 70 are provided on the end surfaces 41 a to 41 a on the one side Y1 in the width direction Y of the connecting members 412 to 412 of the holder members 41 to 41. The restricting members 70 to 70 have concave portions extending along the width direction Y (concave portions 71 to 71 along the width direction Y, here arc-shaped concave grooves having the same diameter in the width direction Y). doing.

  And the adjustment mechanisms 50-50 are set as the structure which presses the pressing members 60-60 in the state close | similar to the recessed strip parts 71-71 within the recessed strip parts 71-71 with respect to the holder members 41-41.

  The pressing member 60 includes cylindrical shaft portions 53 to 53 provided with male screw portions 53b to 53b. The adjustment mechanisms 50 to 50 are provided with female screw portions 54e to 54e that are screwed into the male screw portions 53b to 53b, and support the shaft portions 53 to 53 along the width direction Y. Rotating mechanisms 52 to 52 that rotate ˜53.

  The rotation mechanisms 52 to 52 have first gears 55 to 55 having shaft portions 53 to 53 as rotation axes, and axes 56a to 56a (see FIG. 6) orthogonal to the rotation axes of the first gears 55 to 55 as rotation axes. Second gears 56 to 56 that mesh with the first gears 55 to 55 and drive units 57 to 57 that rotationally drive the second gears 56 to 56 are provided.

  In the present embodiment, the first gears 55 to 55, the second gears 56 to 56, and the drive units 57 to 57 are used to rotate the shaft portions 53 to 53. However, the present invention is not limited to this. Any rotation mechanism can be used as long as it can convert the driving force by the driving units 57 to 57 into a rotational force.

  The protrusions 1b to 1b (see FIG. 4) that act as pivot points for the holder members 41 to 41 are one end portions (one side end portions) 43 to 43 (here, the front side) in the longitudinal direction X of the housing 1a. It is provided on the back side on the opposite side.

  The adjustment mechanisms 50 to 50 are directed toward the shaft portions 53 to 53 in a state where the holder members 41 to 41 (second fθ lenses 37 to 37 in the holder members 41 to 41) are biased so as to be regulated in the height direction Z. The urging portions 51 to 51 are configured to be urged.

  The urging portions 51 to 51 press the second fθ lenses 37 to 37 with the other end portions 48 to 48 of the holder members 41 to 41 by the pressing members 60 to 60 about the one end portions 43 to 43 of the holder members 41 to 41. Kick springs 51a to 51a for urging the second fθ lenses 37 to 37 against one side Y1 in the width direction Y against the force, and holder members 41 to 41 are holder members in the height direction Z from the housing 1a of the exposure unit 1 There are provided restricting portions 51b to 51b for restricting the lifting of 41 to 41 (the movement of the holder members 41 to 41 in the direction perpendicular to the rotation directions C to C) together with the kick springs 51a to 51a.

  Specifically, the kick springs 51a to 51a are provided in the restricting portions 51b to 51b. As for kick springs 51a-51a, the center winding part is penetrated by projection part 1c-1c. The protrusions 1c to 1c are formed on the bottom surface of the housing 1a of the exposure unit 1 and protrude through the through holes 411b to 411b provided in the holder bodies 411 to 411. The size of the through holes 411b to 411b provided in the holder main bodies 411 to 411 is larger than the width of the wound portion at the center of the kick springs 51a to 51a so that the rotation angles φ1 to φ4 of the holder members 41 to 41 can be adjusted. Is also getting bigger. The kick springs 51a to 51a have one end locked to the housing 1a of the exposure unit 1 and the other end locked to the holder main bodies 411 to 411 (here, holes 41c to 41c formed in the holder members 41 to 41). Inserted). The restricting portions 51b to 51b include flat plates 51c to 51c (here, washers) and fixing members 51d to 51d (here, screws) that compress the kick springs 51a to 51a in the height direction Z. The fixing members 51d to 51d fix the flat plates 51c to 51c on the top surfaces of the protrusions 1c to 1c.

  According to the restricting portions 51b to 51b having such a configuration, the other end portions 39 to 39 of the fθ lenses 37 to 37 are pressed against one side Y1 of the width direction Y in the rotation direction C via the kick springs 51a to 51a. be able to. Moreover, the holder members 41 to 41 can be regulated in the height direction Z by pressing the holder members 41 to 41 toward the bottom surface of the housing 1a by compression of the kick springs 51a to 51a. In the present embodiment, the other end portions 48 to 48 of the holder members 41 to 41 correspond to the other end portions 39 to 39 of the second fθ lenses 37 to 37.

  More specifically, the holder main bodies 411 to 411 are long members made of, for example, a metal material. The second fθ lenses 37 to 37 are detachably held by holder bodies 411 to 411 in the holder member 41 by leaf springs 42 to 42 (see FIG. 5).

  In addition, the axial holes 44 to 44 are formed in the end portions 43 to 43 (see FIG. 4) in the longitudinal direction X of the holder members 41 to 41 to be the attachment portions of the one end portions 38 to 38 (see FIG. 4) of the second fθ lenses 37 to 37. 44 is formed. The holder members 41 to 41 are rotatable about the projecting portions 1b to 1b as rotational axes in a state where the projecting portions 1b to 1b of the housing 1a are inserted into the shaft holes 44 to 44, respectively.

  The adjustment mechanisms 50 to 50 are the other end portions 39 of the second fθ lenses 37 to 37 with the protruding portions 1b to 1b at the one end portions 43 to 43 (see FIG. 4) in the longitudinal direction X of the holder members 41 to 41 as rotation axes. The other end portions 48 to 48 (see FIG. 4) in the longitudinal direction X of the holder members 41 to 41 to be attached portions to 39 in the rotation direction CC to the one side Y1 or the other side Y2 in the width direction Y. It is configured to reciprocate to one side (counterclockwise in the illustrated example) or the other side (clockwise in the illustrated example).

  Specifically, the rotation mechanisms 52 to 52 are provided on one side Y1 in the width direction Y of the other end portions 48 to 48 in the longitudinal direction X of the holder members 41 to 41, and the other end of the holder members 41 to 41 in the longitudinal direction X. Pressing force on the other side (clockwise in the illustrated example) of the rotation direction C to C that rotates toward the other side Y2 of the width direction Y with the protrusions 1b to 1b as the rotation axis with respect to the portions 48 to 48 It is set as the structure which gives. The urging portions 51 to 51 are provided on the other side Y2 in the width direction Y of the other end portions 48 to 48 of the holder members 41 to 41 in the longitudinal direction X, and the other ends of the holder members 41 to 41 in the longitudinal direction X. Attached to one side (counterclockwise in the illustrated example) of rotation directions C to C that rotate toward one side Y1 in the width direction Y with the protrusions 1b to 1b as the rotation axis with respect to the portions 48 to 48. It is configured to give power. Thereby, the rotation angles φ1 to φ4 in the rotation directions C to C of the second fθ lenses 37 to 37 can be adjusted, and the irradiation position of the laser beam to the photosensitive drums 3 to 3 can be automatically adjusted. it can.

  In the rotation mechanisms 52 to 52, when the drive units 57 to 57 are operated and controlled by an instruction signal from the main control unit 300, the second gears 56 to 56 are rotationally driven and the first gears 55 to 55 are driven to rotate. . As a result, by rotating the shaft portions 53 to 53 that are supported in a state of being screwed to the shaft support portions 54 to 54, the protruding portions are formed with respect to the other end portions 48 to 48 in the longitudinal direction X of the holder members 41 to 41. Automatic adjustment is realized by applying a pressing force to the other side (clockwise in the illustrated example) of the rotation directions C to C rotating about the rotation axis 1b to 1b toward the other side Y2 of the width direction Y. It becomes possible.

  When the shaft portions 53 to 53 are retracted to the one side Y1 in the width direction Y, the adjusting mechanisms 50 to 50 are pressed by the biasing portions 51 to 51 against the holder members 41 to 41 by the shaft portions 53 to 53. By applying an urging force against the above, the other end portions 48 to 48 in the longitudinal direction X of the holder members 41 to 41 are reliably secured to the shaft portions 53 to 53 retracting to the one side Y1 in the width direction Y. It is possible to follow.

  The shaft parts 53 to 53 (see FIGS. 5 to 7) in the rotation mechanisms 52 to 52 reduce the wear of at least one of the shaft parts 53 to 53 and the connecting members 412 to 412 in the holder members 41 to 41 as much as possible. Therefore, the contact portion with the connecting members 412 to 412 at the tip is formed in a spherical shape. Moreover, as for the axial parts 53-53, the external thread parts 53b-53b are formed in the front-end | tip parts 53a-53a. Moreover, the shape of the center parts 53e-53e (refer FIG. 6) of the axial parts 53-53 and the base end parts 53c-53c is formed in D shape by sectional view. The first gears 55 to 55 have through holes 55a to 55a. The through holes 55a to 55a are D-shaped holes corresponding to the D-shapes of the shaft portions 53 to 53. As described above, the first gears 55 to 55 having the D-shaped through holes 55 a to 55 a are inserted into the D-shaped central portions 53 e to 53 e of the shaft portions 53 to 53, so that the shaft portions 53 to 53 of the shaft portions 53 to 53 are inserted. Movement in the circumferential direction (relative rotation around the axis with respect to the shaft portions 53 to 53) can be easily and easily prevented.

  Here, the shaft support portions 54 to 54 include bottom surface portions 54 a to 54 a and two wall portions 54 b to 54 b and 54 c to 54 c. One of the two wall portions 54b to 54b and 54c to 54c is inserted into one of the wall portions 54b to 54b through which the shaft portions 53 to 53 are movably inserted in the width direction Y (axial direction) (FIG. 6). The other wall portions 54c to 54c are provided with female screw portions 54e to 54e (see FIGS. 6 and 7) that mesh with the male screw portions 53b to 53b of the shaft portions 53 to 53. .

  The shaft support portions 54 to 54 can move the shaft portions 53 to 53 in the width direction Y (axial direction) by engaging the male screw portions 53 b to 53 b of the shaft portions 53 to 53 with the female screw portions 54 e to 54 e. Can be held.

  Here, the first gears 55 to 55 are crown gears, and the D-shaped center portions 53e to 53e of the shaft portions 53 to 53 are inserted into the D-shaped through holes 55a to 55a in the shaft center portion. It has come to be. As a result, the shaft portions 53 to 53 can be rotated in conjunction with the rotation of the first gears 55 to 55.

  Here, the second gears 56 to 56 are spur gears connected to the shafts 56a to 56a, and the shafts 56a to 56a and the shaft portions 53 to 53 provided with the first gears 55 to 55 are orthogonal to each other. It is arranged like this. The second gears 56 to 56 mesh with the first gears 55 to 55, and the shafts 56 a to 56 a serve as the rotation shafts of the drive units 57 to 57. Thereby, the shaft parts 53 to 53 can be rotated via the shafts 56 a to 56 a, the second gears 56 to 56, and the first gears 55 to 55 by rotationally driving the drive parts 57 to 57.

  Here, the drive units 57 to 57 are drive motors, and the drive unit main body is provided outside the housing 1a with the shafts 56a to 56a connected to the second gears 56 to 56 inserted inside the housing 1a. It is done. The drive units 57 to 57 perform switching control of on / off of excitation. Therefore, the drive units 57 to 57 are not always excited, and are excited when the positions of the second fθ lenses 37 to 37 are adjusted. Specifically, the main control unit 300 excites the drive units 57 to 57 only when the positions of the second fθ lenses 37 to 37 are automatically adjusted. Thereby, it is possible to prevent the heat generation of the motor due to the excitation to the drive units 57 to 57 except when the positions of the second fθ lenses 37 to 37 are automatically adjusted.

  In the adjustment mechanisms 50 to 50 described above, the drive units 57 to 57 are rotationally driven, whereby the second gears 56 to 56 are rotationally driven. As the second gears 56 to 56 rotate, the first gears 55 to 56 are rotated. 55 rotates, and further, the shaft portions 53 to 53 rotate. At this time, since the male screw parts 53b to 53b of the shaft parts 53 to 53 and the female screw parts 54e to 54e of the shaft support parts 54 to 54 are engaged with each other, the shaft part is selected according to the rotation direction of the first gears 55 to 55. 53 to 53 are either one of the other side Y2 in the width direction Y (specifically, the holder member 41 side) and one side Y1 in the width direction Y (specifically, the side opposite to the holder member 41). Move in the direction. In this way, the other end portion 48 in the longitudinal direction X of the holder members 41 to 41 that contact the tip ends of the shaft portions 53 to 53 with the protrusions 1b to 1b in the one end portions 43 to 43 in the longitudinal direction X as rotation axes. ˜48 can swing, and the rotation angles φ1 to φ4 in the rotation directions C to C of the second fθ lenses 37 to 37 mounted on the holder members 41 to 41 can be automatically adjusted, whereby the second fθ lens 37 can be adjusted. It is possible to automatically adjust the irradiation position of the laser beam irradiated to the photosensitive drums 3 to 3 through .about.37.

(Manual adjustment mechanism)
FIG. 8 is an enlarged perspective view of a main part mainly showing the adjustment units 40 to 40 and the second fθ lenses 37 to 37 in the manual adjustment mechanism 10 b of the exposure unit 1. 9 is a cross-sectional view taken along line BB shown in FIG. FIG. 10 is a schematic configuration diagram schematically showing the adjustment units 40 to 40 shown in FIG. 9. The restricting members 70 to 70 in the manual adjustment mechanism 10b are the same as the configuration of the manual adjustment mechanism 10b, and detailed description thereof is omitted here.

  In addition to the configuration of the automatic adjustment mechanism 10a, the rotation mechanisms 52 to 52 include manual adjustment units 58 to 58 that manually adjust the irradiation positions of the laser beams on the photosensitive drums 3 to 3.

  The manual adjustment units 58 to 58 include manual shaft portions 58a to 58a that are manually rotatable, and manual gears 58b to 58b connected to the manual shaft portions 58a to 58a.

  As for the manual shaft parts 58a-58a, the base end parts 58e-58e side protrudes on the outer side of the front side of the housing 1a so that it may orthogonally cross with the rotating shaft (shaft parts 53-53) of the 1st gears 55-55. The manual shaft portions 58a to 58a are inserted into the through holes 1d to 1d formed in the housing 1a, the distal end portions 58c to 58c are located inside the housing 1a, and the base end portions 58e to 58e are the housing 1a. It arrange | positions so that it may be located outside. The manual shaft portions 58a to 58a are such that the central portions 58d to 58d (see FIGS. 9 and 10) in the longitudinal direction X (axial direction) are movable in the longitudinal direction X (axial direction) with respect to the housing 1a. It is supported so as to be rotatable around its axis.

  Further, the manual shafts 58a to 58a are provided with manual gears 58b to 58b at the tip portions 58c to 58c. Specifically, the manual gears 58b to 58b are fixed to the manual shafts 58a to 58a by two fixing members (specifically, E rings) 58f to 58f.

  Moreover, the manual adjustment parts 58-58 are further provided with the compression spring parts 58g-58g. The compression spring portions 58g to 58g are configured to apply a biasing force in a direction from the inner side (the distal end portions 58c to 58c side) to the outer side (the base end portions 58e to 58e side) with respect to the manual shaft portions 58a to 58a. Yes. Specifically, the compression spring portions 58g to 58g are inserted through center portions 58d to 58d located outside the housing 1a, and are provided between the housing 1a and the base end portions 58e to 58e.

  The manual gears 58b to 58b have a meshing position (see FIG. 10) that meshes with the first gears 55 to 55 and a non-meshing position (see FIG. 9) in which the meshing state with the first gears 55 to 55 is released. It is like that.

  In the adjustment mechanisms 50 to 50 described above, when the external force is not applied to the compression spring portions 58g to 58g, the manual gears 58b to 58b are arranged at the non-meshing position, and the first gears 55 to 55 of the manual gears 58b to 58b. The meshing state with respect to 55 is released (see FIG. 9). On the other hand, when an external force (pressing force by the user) is applied from the outside (base end portions 58e to 58e side) to the inside (tip portions 58c to 58c side) against the urging force of the compression spring portions 58g to 58g, The gears 58b to 58b are moved inward (on the front end portions 58c to 58c side), arranged at the meshing position, and meshed with the first gears 55 to 55 (see FIG. 10). Thus, the manual shafts 58a to 58a are rotated around the axis while being pressed inward (to the tip portions 58c to 58c) by the user, and the first gears 55 to 55 are driven to rotate via the manual gears 58b to 58b. Thereby, the rotation angles φ1 to φ4 in the rotation directions C to C of the second fθ lenses 37 to 37 can be adjusted, and the irradiation position of the laser beam to the photosensitive drums 3 to 3 can be manually adjusted. it can.

(About the adjustment mechanism)
In 50 to 50 having such a configuration, when the irradiation position of the laser beam to the photosensitive drums 3 to 3 is automatically adjusted, the manual gears 58b to 58b of the manual adjustment units 58 to 58 are replaced with the first gears 55 to 55. While the automatic adjustment is performed by the driving units 57 to 57 without being engaged with each other, when manually adjusting the irradiation position of the laser beam to the photosensitive drums 3 to 3, the manual gear 58 b of the manual adjustment unit 58 is adjusted by the user. Manual adjustment is performed by meshing with one gear 55.

(About this embodiment)
As described above, according to the present embodiment, when adjusting the rotation angles φ1 to φ4 in the rotation directions C to C of the second fθ lenses 37 to 37 by the adjustment mechanisms 50 to 50, the regulating members 70 to 70 are adjusted. Can regulate the inclination of the second fθ lenses 37 to 37 around the longitudinal axes α1 to α4, thereby suppressing the inclination of the second fθ lenses 37 to 37 around the longitudinal axes α1 to α4. Inconvenience associated with the inclination of the second fθ lenses 37 to 37 around the longitudinal axes α1 to α4, for example, occurrence of image defects due to stray light can be suppressed.

  In the present embodiment, the regulating members 70 to 70 are provided so as to protrude on one side Y1 in the width direction Y of the holder members 41 to 41, and the inclinations of the second fθ lenses 37 to 37 around the longitudinal axes α1 to α4. Since the abutting members 60 to 60 are in contact with each other, the inclination of the second fθ lenses 37 to 37 around the longitudinal axes α1 to α4 can be restricted by the restriction member 70 having a simple configuration.

  In the present embodiment, the second fθ lens 37 is provided by the regulating members 70 to 70 provided on one side Z1 (here, the lower side) of the holder members 41 to 41 in the height direction Z with respect to the pressing members 60 to 60. The inclination to the other side Z2 (here, the upper side) of the height direction Z of .about.37 can be regulated.

  Moreover, in this Embodiment, the restriction | limiting provided between the guide members 59-59 located in the one side Z1 (here lower side) of the height direction Z of the holder members 41-41, and the pressing members 60-60. The members 70 to 70 can regulate the inclination of the second fθ lenses 37 to 37 toward the one side Z1 (here, the lower side) and the other side Z2 (here, the upper side) in the height direction Z.

  By the way, when the pressing members 60 to 60 and the holder members 41 to 41 are provided apart from each other, the pressing members 60 to 60 may be extended to the other side Y2 in the width direction Y. Therefore, in the present embodiment, the holder members 41 to 41 include holder main bodies 411 to 411 and connecting members 412 to 412. And the adjustment mechanisms 50-50 are set as the structure which presses the pressing members 60-60 with respect to the connection members 412-412 connected with the end surfaces 41a-41a of the one side Y1 of the width direction Y in the holder main bodies 411-411. Therefore, since the second fθ lenses 37 to 37 are easily inclined around the longitudinal axis α1 to α4, the regulating members 70 to 70 are provided on the connecting members 412 to 412. Therefore, the longitudinal lengths of the second fθ lenses 37 to 37 are increased. It is possible to reliably suppress the inclination around the directional axes α1 to α4.

  Moreover, in this Embodiment, the adjustment members 50-50 are made to press the pressing members 60-60 with respect to the end surfaces 41a-41a of the one side Y1 of the width direction Y in the elongate connection members 412-412 extended in the width direction Y. Since it is set as the structure pressed toward the other side Y2 of the width direction Y, it becomes possible to press the pressing members 60-60 stably with respect to the connection members 412-412.

  In the present embodiment, the adjustment mechanisms 50 to 50 are configured to press the pressing members 60 to 60 against the holder members 41 to 41 toward the longitudinal axes α1 to α4 of the second fθ lenses 37 to 37. Therefore, it is possible to reliably suppress the inclination of the second fθ lenses 37 to 37 around the longitudinal axes α1 to α4.

  Moreover, in this Embodiment, the regulation members 70-70 press the pressing members 60-60 within the recessed strip parts 71-71 in the regulation members 70-70 with respect to the holder members 41-41 with the adjustment mechanisms 50-50. Since it is set as the structure, the pressing members 60 to 60 are pressed against the holder members 41 to 41 in a state where the pressing members 60 to 60 avoid interference with the restricting members 70 to 70 while maintaining the strength of the restricting members 70 to 70. Can be pressed.

  Moreover, in this Embodiment, since the pressing members 60-60 have the axial parts 53-53 and the adjustment mechanisms 50-50 are provided with the axial support parts 54-54 and the rotation mechanisms 52-52, it is simple structure. However, in a state where the male screw portions 53b in the shaft portions 53 to 53 are screwed to the female screw portions 54e to 54e in the shaft support portions 54 to 54, the shaft portions 53 to 53 are rotated by the rotation mechanisms 52 to 52. It can be rotated to one side or the other side of the periphery, and can be moved to one side Y1 or the other side Y2 in the width direction Y. Accordingly, the rotation angles φ1 to φ4 in the rotation directions C to C of the second fθ lenses 37 to 37 can be adjusted according to the rotation amount of the shaft portions 53 to 53. In addition, since the shaft portions 53 to 53 do not move to the one side Y1 or the other side Y2 in the width direction Y unless the second gears 56 to 56 are rotated to one side or the other side around the axis, the shaft portion 53 is not moved. It becomes possible to easily maintain the position in the width direction Y of ˜53.

  In the present embodiment, since the rotation mechanism includes the first gears 55 to 55, the second gears 56 to 56, and the drive units 57 to 57, the rotation shaft (the shaft portion 53) of the first gears 55 to 55. The second gears 56 to 56 meshing with the first gears 55 to 55 can be rotationally driven by the drive units 57 to 57 with the shaft 56a orthogonal to the. Thereby, even if the rotational drive of the drive parts 57-57 is stopped, the 2nd gears 56-56 rotate to the one side or the other side around an axis line, and, as a result, the shaft parts 53-53 are one side of the width direction Y. It can prevent effectively moving to Y1 or the other side Y2. Thereby, it becomes possible to maintain the position of the axial direction 53-53 of the width direction Y reliably.

  Moreover, in this Embodiment, since the projection parts 1b-1b which act as a rotation fulcrum of the holder members 41-41 are provided in the one end parts 43-43 of the longitudinal direction X, the projection parts 1b-1b are made into a longitudinal direction. Compared with the case where the second fθ lenses 37 to 37 are provided at the central portion of X, the radius of rotation around the rotation fulcrum of the second fθ lenses 37 to 37 can be increased, and the rotation of the second fθ lenses 37 to 37 in the rotation directions C to C can be increased. It becomes easy to finely adjust the angles φ1 to φ4.

  In this embodiment, since adjustment mechanisms 50-50 are provided with urging parts 51-51, it is attached so that holder members 41-41 may be regulated in height direction Z by urging parts 51-51. The second fθ lenses 37 to 37 can be urged to the one side Y1 in the width direction Y in the biased state, so that even if the pressing members 60 to 60 are displaced to the one side Y1 in the width direction Y, the second fθ The rotation angle of the second fθ lenses 37 to 37 in the rotation directions C to C with respect to the one side Y1 of the width direction Y with the pressing members 60 to 60 in a state where the inclination of the lenses 37 to 37 around the longitudinal axes α1 to α4 is suppressed. Adjustment of φ1 to φ4 can be easily performed.

  Note that the image forming apparatus 100 (color image forming apparatus) to which the exposure unit 1 according to the present embodiment is applied is a multi-function machine here, but the exposure unit 1 is an image of a copying machine, a printer, a facsimile machine or the like. It can also be applied to a forming apparatus. The exposure unit 1 may be a monochrome exposure unit and may be applied to a monochrome image forming apparatus.

1 Exposure unit (an example of an optical scanning device)
1a Housing 1b Protrusion (an example of a rotation fulcrum)
3 Photosensitive drum (an example of a scanned object)
30 Laser emitting part (an example of a light source)
35 Rotating polygon mirror (example of deflector)
37 second fθ lens (an example of an optical member)
41 Holder member 41a End surface 411 Holder body 412 Connecting member 50 Adjusting mechanism 51 Energizing part 51a Kick spring 51b Restricting part 52 Rotating mechanism 53 Shaft part 53b Male thread part 54e Female thread part 54 Shaft support part 55 First gear 56 Second gear 57 Drive part 59 Guide member 59a Opposing surface 60 Pressing member 70 Restricting member 71 Convex section 100 Image forming apparatus C Rotating direction X Longitudinal direction Y Width direction Z Height direction α1 to α4 Longitudinal axis γ Reference virtual straight line δ Height direction axis φ1 ~ Φ4 rotation angle

Claims (13)

A light source, a deflector that deflects and scans light from the light source onto a scanned object, a long optical member disposed between the deflector and the scanned object, and a longitudinal direction of the optical member An optical scanning device comprising: an adjustment mechanism for adjusting a rotation angle of the optical member in a rotation direction in which the optical member rotates about a height direction axis along a perpendicular height direction;
The adjustment mechanism includes a regulating member that regulates the inclination of the optical member around the longitudinal axis along the longitudinal direction ,
The adjustment mechanism includes a holder member that holds the optical member and is rotatable about a rotation axis along the height direction, and a longitudinal direction and a height direction of the holder member. A pressing member that presses the end surface on one side in the width direction orthogonal to both sides toward the other side in the width direction and rotates the holder member about the rotation shaft as the rotation fulcrum;
The regulating member protrudes from one side of the holder member in the width direction, and is configured to abut against the pressing member when regulating the inclination of the optical member around the longitudinal axis. An optical scanning device. The optical scanning device according to claim 1 ,
The optical scanning device according to claim 1, wherein the regulating member is provided on one side of the holder member in the height direction with respect to the pressing member. The optical scanning device according to claim 1 or 2 ,
The adjustment mechanism includes a guide member located on one side in the height direction of the holder member,
The optical scanning device according to claim 1, wherein the regulating member is provided between the guide member and the pressing member. The optical scanning device according to any one of claims 1 to 3 , wherein
The holder member includes a holder main body that holds the optical member, and a connecting member that is connected to one end face in the width direction of the holder main body,
The adjustment mechanism is configured to press the pressing member against the connecting member,
The optical scanning device according to claim 1, wherein the regulating member is provided on the connecting member. The optical scanning device according to claim 4 ,
The connecting member is a long member extending in the width direction,
The optical scanning device according to claim 1, wherein the adjusting mechanism is configured to press the pressing member toward the other side in the width direction against an end face on the one side in the width direction of the connecting member. The optical scanning device according to any one of claims 1 to 5 , wherein
The optical scanning apparatus according to claim 1, wherein the adjustment mechanism is configured such that a virtual straight line along a direction of a force pressing the pressing member against the holder member intersects the longitudinal axis of the optical member. The optical scanning device according to any one of claims 1 to 5 , wherein
The restricting member is provided on an end surface on one side in the width direction of the holder member, and has a concave portion extending along the width direction,
The optical scanning device according to claim 1, wherein the adjustment mechanism is configured to press the pressing member within the concave portion against the holder member. The optical scanning device according to any one of claims 1 to 7 ,
The pressing member has a shaft portion provided with a male screw portion,
The adjustment mechanism includes a shaft support portion that is provided with a female screw portion that is screwed into the male screw portion and supports the shaft portion along the width direction, and a rotation mechanism that rotates the shaft portion. An optical scanning device. The optical scanning device according to claim 8 ,
The rotation mechanism includes a first gear having the shaft portion as a rotation axis, a second gear meshing with the first gear with an axis orthogonal to the rotation axis of the first gear as a rotation axis, and the second gear. An optical scanning device comprising: a drive unit that rotates. An optical scanning device according to any one of claims 1 to 9 , wherein
The optical scanning device, wherein the rotation fulcrum is provided at one end portion in the longitudinal direction. The optical scanning apparatus according to any one of claims 1 to 1 0,
The adjustment mechanism includes an urging unit configured to urge the holder member toward the pressing member while being urged so as to restrict the holder member in the height direction. apparatus. The optical scanning device according to any one of claims 1 to 11, wherein
The optical member is a plurality of optical members disposed between the deflector and the scanned body,
The adjustment mechanism is a plurality of adjustment mechanisms that respectively adjust rotation angles of the plurality of optical members in a rotation direction in which the plurality of optical members rotate about the height direction axis.
The optical scanning device according to claim 1, wherein the restricting members are a plurality of restricting members for restricting inclinations of the plurality of optical members around the longitudinal axis. An image forming apparatus characterized by comprising an optical scanning device according to any one of claims 1 to 1 2.

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