Optical scanning device and image formation device

Abstract

To adjust a plurality of apertures corresponding to a plurality of multi-beam light sources with a simple mechanism.SOLUTION: An aperture unit 530 includes a plurality of apertures 53 for transmitting a plurality of sets of beam light sets B2 transmitting through a plurality of lenses 52. The optical scanner 54 reflects and scans the plurality of sets of beam light sets B2 transmitting through the plurality of apertures 53. A support mechanism 58 supports the aperture unit 530, and can change the position of the aperture unit 530 in a direction of light travel from the plurality of lenses 52 to the optical scanner 54 and the angle of the aperture unit 520 with respect to the direction of light travel.SELECTED DRAWING: Figure 6

Description

[Technical Field]

[0001] The present invention relates to an optical scanning device and an image forming apparatus that include a multi-beam light source. [Background technology]

[0002] An electrophotographic image forming apparatus includes an optical scanning device that forms an electrostatic latent image on the surface of a photosensitive member, and the optical scanning device includes an optical scanner such as a polygon mirror and other optical devices.

[0003] The optical scanning device may include a multi-beam light source that emits a beam light set consisting of a plurality of beam light beams, and an aperture that passes the beam light set, the aperture being disposed between the multi-beam light source and the optical scanner.

[0004] For example, it is known that the aperture is disposed on one substrate together with the optical scanner (see, for example, Patent Document 1). [Prior art documents] [Patent documents]

[0005] [Patent Document 1] Japanese Patent Application Laid-Open No. 2002-23093 Summary of the Invention [Problem to be solved by the invention]

[0006] In the optical scanning device, the position of the aperture needs to be adjusted. When the image forming apparatus is a tandem color image forming apparatus, the optical scanning device includes a plurality of the multi-beam light sources and a plurality of the apertures.

[0007] When the optical scanning device includes a plurality of the multi-beam light sources, it is desirable that the plurality of apertures corresponding to the plurality of the multi-beam light sources can be adjusted by a mechanism that is as simple as possible.

[0008] SUMMARY OF THE INVENTION An object of the present invention is to provide an optical scanning device and an image forming device that can adjust a plurality of apertures corresponding to a plurality of multi-beam light sources using a simple mechanism. [Means for solving the problem]

[0009] According to one aspect of the present invention, an optical scanning device includes a plurality of multi-beam light sources, a plurality of lenses, an aperture unit, an optical scanner, and a support mechanism. The plurality of multi-beam light sources each emit a plurality of light beam sets each consisting of a plurality of light beams. The plurality of lenses pass each of the plurality of light beam sets. The aperture unit has a plurality of apertures that pass each of the plurality of light beam sets that have passed through the plurality of lenses. The optical scanner scans while reflecting the plurality of light beam sets that have passed through the plurality of apertures. The support mechanism supports the aperture unit and is capable of changing the position of the aperture unit in the light traveling direction from the plurality of lenses to the optical scanner and the angle of the aperture unit with respect to the light traveling direction.

[0010] According to another aspect of the present invention, an image forming apparatus includes a plurality of photoconductors, the optical scanning device, a plurality of developing devices, and a transfer device. The optical scanning device forms electrostatic latent images on the surfaces of the plurality of photoconductors by scanning the plurality of light beam sets over the surfaces of the plurality of photoconductors. The plurality of developing devices develop the electrostatic latent images on the surfaces of the plurality of photoconductors into toner images. The transfer device transfers the toner images on the surfaces of the plurality of photoconductors to a sheet. [Effects of the Invention]

[0011] According to the present invention, it is possible to provide an optical scanning device and an image forming device that can adjust a plurality of apertures corresponding to a plurality of multi-beam light sources using a simple mechanism. [Brief explanation of the drawings]

[0012] [Figure 1] FIG. 1 is a diagram showing the configuration of an image forming apparatus including an optical scanning unit according to an embodiment. [Figure 2] FIG. 2 is a configuration diagram of the optical scanning unit according to the embodiment. [Figure 3] FIG. 3 is a perspective view of the inside of the optical scanning unit according to the embodiment. [Figure 4] FIG. 4 is a perspective view of a plurality of multi-beam light sources and a plurality of lenses in the optical scanning device according to the embodiment. [Figure 5] FIG. 5 is a front view of the aperture unit in the optical scanning device according to the embodiment. [Figure 6] FIG. 6 is a diagram showing the configuration of a plurality of devices arranged on the optical path up to the optical scanner in the optical scanning device according to the embodiment. [Figure 7] FIG. 7 is a diagram showing a first adjustment state of the support mechanism in the optical scanning device according to the embodiment. [Figure 8] FIG. 8 is a diagram showing a second adjustment state of the support mechanism in the optical scanning device according to the embodiment. DETAILED DESCRIPTION OF THE INVENTION

[0013] Hereinafter, an embodiment of the present invention will be described with reference to the drawings. Note that the following embodiment is an example of the present invention, and does not limit the technical scope of the present invention.

[0014] An image forming apparatus 10 according to the embodiment performs a print process by electrophotography. The print process is a process of forming an image on a sheet 9. The sheet 9 is an image formation medium such as paper or a sheet-like resin member.

[0015] 1 is a printer. The image forming apparatus 10 may also be a copier, a facsimile machine, a multifunction peripheral, or the like.

[0016] [Configuration of image forming apparatus 10] As shown in FIG. 1, an image forming apparatus 10 includes a main housing 1, and a sheet conveying device 3, a printing device 4, and a control device 8 housed within the main housing 1.

[0017] The sheet transport device 3 includes a sheet feeding mechanism 30 and a plurality of pairs of transport rollers 31. The sheet feeding mechanism 30 sends out the sheets 9 stored in the sheet storage unit 2 to a transport path 300. The transport path 300 is a path along which the sheets 9 are transported.

[0018] The plurality of pairs of transport rollers 31 rotate to transport the sheet 9 along the transport path 300. Furthermore, the plurality of pairs of transport rollers 31 discharge the sheet 9 on which an image has been formed in the transport path 300 onto a discharge tray 1x.

[0019] The image forming apparatus 10 includes a tandem printing device 4. The printing device 4 includes an optical scanning device 5, a plurality of image forming units 4x, a transfer device 44, and a fixing device 46. The plurality of image forming units 4x correspond to a plurality of developing colors.

[0020] Each image forming unit 4x includes a drum-shaped photoconductor 41, a charging device 42, a developing device 43, and a drum cleaning device 45. That is, the printing device 4 includes a plurality of photoconductors 41, a plurality of developing devices 43, and a plurality of drum cleaning devices 45 corresponding to a plurality of developing colors.

[0021] Each photoconductor 41 rotates, and each charging device 42 charges the surface of each photoconductor 41. The optical scanning device 5 scans multiple light beams over the charged surfaces of the multiple photoconductors 41. In this way, the optical scanning device 5 forms an electrostatic latent image on the surface of each photoconductor 41.

[0022] The developing devices 43 develop the electrostatic latent images into toner images by supplying toner to the surfaces of the photoreceptors 41. The toner is a granular developer. The photoreceptors 41 are an example of an image carrier that rotates while carrying the toner image.

[0023] In this embodiment, the printing device 4 includes four image forming units 4x corresponding to the toners of four developing colors, namely, yellow, cyan, magenta, and black, and therefore includes four photoconductors 41, four developing devices 43, and four drum cleaning devices 45.

[0024] The four toner images are formed on the surfaces of the four photoconductors 41. The transfer device 44 transfers the toner images on the surfaces of the four photoconductors 41 onto a sheet 9.

[0025] The transfer device 44 includes an intermediate transfer belt 441, four primary transfer devices 442 corresponding to the four image forming units 4x, a secondary transfer device 443, and a belt cleaning device 444.

[0026] The four primary transfer devices 442 transfer the toner images on the surfaces of the four photosensitive drums 41 onto the surface of the intermediate transfer belt 441. As a result, a color toner image, which is a composite of the toner images on the four photosensitive drums 41, is formed on the surface of the intermediate transfer belt 441.

[0027] The secondary transfer device 443 transfers the color toner image formed on the intermediate transfer belt 441 onto the sheet 9 at a transfer position on the conveyance path 300 .

[0028] The fixing device 46 applies heat and pressure to the color toner image transferred onto the sheet 9. In this way, the fixing device 46 fixes the color toner image onto the sheet 9.

[0029] Each drum cleaning device 45 removes waste toner remaining on the surface of each photoconductor 41. The belt cleaning device 444 removes the waste toner remaining on the intermediate transfer belt 441.

[0030] 2 and 3, the optical scanning device 5 includes a unit housing 50 and a plurality of optical devices housed in the unit housing 50. The unit housing 50 is a molded member made of synthetic resin.

[0031] The optical devices include a plurality of light sources 51, a plurality of first lenses 52, a plurality of apertures 53, an optical scanner 54, one or more second lenses 55, a plurality of mirrors 56, and one or more third lenses 57.

[0032] In this embodiment, the optical scanner 54 is a polygon mirror. The polygon mirror has a plurality of mirrors arranged in a regular polygonal shape in the circumferential direction. The polygon mirror is rotated by being driven by a polygon motor 541 (see FIG. 2).

[0033] Alternatively, a galvanometer mirror or a MEMS mirror (Micro Electro Mechanical Systems mirror) may be employed as the optical scanner 54.

[0034] The optical scanning device 5 further includes an electronic board 540 on which a circuit for driving the polygon motor 541 is mounted. That is, a circuit for driving the optical scanner 54 is implemented on the electronic board 540.

[0035] The plurality of light sources 51 each emit a plurality of light beam sets B2 each consisting of a plurality of light beams B1 (see FIGS. 2, 4, and 6). That is, the plurality of light sources 51 are a plurality of multi-beam light sources each emitting the plurality of light beam sets B2.

[0036] For example, each of the light sources 51 is a multi-beam laser diode that emits a light beam set B2 including a plurality of laser beams.

[0037] In this embodiment, the optical scanning device 5 forms the electrostatic latent images on the surfaces of the four photoconductors 41 by scanning the surfaces of the four photoconductors 41 with the four light beam sets B2.

[0038] The plurality of first lenses 52 respectively transmit the plurality of light beam sets B2. Each of the first lenses 52 is a cylindrical lens.

[0039] The plurality of apertures 53 respectively transmit the plurality of light beam sets B2 that have passed through the plurality of first lenses 52 (see FIG. 5). The optical scanner 54 reflects and scans the plurality of light beam sets B2 that have passed through the plurality of apertures 53.

[0040] One or more second lenses 55 and one or more third lenses 57 pass multiple sets of light beams B2 scanned by the optical scanner 54. The second lenses 55 and the third lenses 57 are fθ lenses. In this embodiment, the optical scanning device 5 includes two second lenses 55 and two third lenses 57, each of which passes two sets of light beams B2.

[0041] The plurality of mirrors 56 reflect the plurality of light beam sets B2 that have passed through the second lens 55 and the third lens 57 toward the surfaces of the corresponding plurality of photoconductors 41. In this way, the surfaces of the plurality of photoconductors 41 are scanned with the plurality of light beam sets B2.

[0042] In this embodiment, the optical scanning device 5 includes four light sources 51 corresponding to the four development colors. Each light source 51 emits a light beam set B2 consisting of two light beams B1. Therefore, the optical scanning device 5 scans the surfaces of the four photoconductors 41 with the four light beam sets B2, each consisting of two light beams B1.

[0043] The control device 8 controls the sheet transport device 3 and the printing device 4. For example, the control device 8 controls the formation of the electrostatic latent images on the surfaces of the photoconductors 41 by controlling the light sources 51 and the polygon motor 541 in the optical scanning device 5.

[0044] Incidentally, it is necessary to adjust the position of each of the apertures 53 in the optical scanning device 5. Since the image forming apparatus 10 is a tandem color image forming apparatus, the optical scanning device 5 includes a plurality of light sources 51 and a plurality of apertures 53, each of which emits a light beam set B2 (see FIG. 4).

[0045] In the optical scanning device 5, it is desirable to be able to adjust the plurality of apertures 53 corresponding to the plurality of light sources 51 using a mechanism that is as simple as possible.

[0046] The optical scanning device 5 includes one or more aperture units 530 and a support mechanism 58 that supports the aperture units 530 in order to adjust the positions of the plurality of apertures 53 (see FIGS. 3, 5, and 6).

[0047] 3 and 5, the optical scanning device 5 includes two aperture units 530 corresponding to the two light beam sets B2, respectively. Each aperture unit 530 has two apertures 53 (see FIG. 5). A support mechanism 58 supports each aperture unit 530.

[0048] Here, the direction from the plurality of first lenses 52 toward the optical scanner 54 is referred to as the light propagation direction D1. The four light sources 51 include two light source sets 510 (see FIG. 4). Each light source set 510 includes two light sources 51 arranged in an arrangement direction D2 that intersects with the light propagation direction D1. In this embodiment, the arrangement direction D2 is the vertical direction (see FIGS. 4 and 6).

[0049] Each aperture unit 530 includes two apertures 53 that pass two sets of light beams B2 emitted from each light source set 510 (see FIG. 5).

[0050] The support mechanism 58 is capable of changing the position of each aperture unit 530 in the light traveling direction D1 and the angle of each aperture unit 530 with respect to the light traveling direction D1.

[0051] The support mechanism 58 includes a rotation support mechanism 581 , a slide support mechanism 582 , an angle fixing mechanism 583 , and a position fixing mechanism 584 .

[0052] Rotation support mechanism 581 supports each aperture unit 530 rotatably around support shaft 581a arranged along axial direction D3 (see FIG. 6). Axial direction D3 is a direction intersecting light traveling direction D1 and arrangement direction D2.

[0053] The slide support mechanism 582 supports the rotation support mechanism 581 so that the rotation support mechanism 581 is movable along the light traveling direction D1.

[0054] Angle fixing mechanism 583 fixes each aperture unit 530 at any angle within the range of rotational movement. Position fixing mechanism 584 fixes rotation support mechanism 581 at any position within the range of movement in light traveling direction D1.

[0055] 6 shows a reference state of support mechanism 58. The reference state is a state in which one of aperture units 530 is fixed at a reference angle, and rotation support mechanism 581 is fixed at a reference position in light traveling direction D1.

[0056] 7 shows a first adjustment state of support mechanism 58. The first adjustment state is a state in which one of aperture units 530 is fixed at an angle different from the reference angle, and rotation support mechanism 581 is fixed at the reference position.

[0057] 8 shows a second adjustment state of support mechanism 58. The second adjustment state is a state in which one of aperture units 530 is fixed at an angle different from the reference angle, and rotation support mechanism 581 is fixed at a position different from the reference position.

[0058] In the optical scanning device 5, a plurality of light beam sets B2 can be adjusted by adjusting one aperture unit 530. In this embodiment, two light beam sets B2 can be adjusted by adjusting one aperture unit 530.

[0059] By employing the optical scanning device 5, it is possible to adjust the plurality of apertures 53 corresponding to the plurality of light sources 51 using a simple mechanism.

[0060] Each of the light sources 51 may be a multi-beam light source that emits a light beam set B2 including three or more light beams B1.

[0061] [Notes on the Invention] The following is a summary of the invention extracted from the above-described embodiment. Note that the configurations and processing functions described in the following supplementary notes can be selected and combined as desired.

[0062] <Appendix 1> a plurality of multi-beam light sources each emitting a plurality of light beam sets each including a plurality of light beams; a plurality of lenses through which the plurality of light beam sets pass, respectively; an aperture unit having a plurality of apertures that respectively transmit the plurality of light beam sets that have passed through the plurality of lenses; an optical scanner that reflects and scans the plurality of light beam sets that have passed through the plurality of apertures; an optical scanning device comprising: a support mechanism that supports the aperture unit and is capable of changing the position of the aperture unit in the direction of light travel from the plurality of lenses to the optical scanner and the angle of the aperture unit with respect to the direction of light travel.

[0063] <Appendix 2> A plurality of photoreceptors; an optical scanning device according to claim 1, which scans a plurality of light beam sets, each consisting of a plurality of light beams, on the surfaces of the plurality of photosensitive members to form electrostatic latent images on the surfaces of the plurality of photosensitive members; a plurality of developing devices for developing the electrostatic latent images on the surfaces of the plurality of photoreceptors into toner images; a transfer device that transfers the toner images on the surfaces of the plurality of photosensitive members onto a sheet. [Explanation of symbols]

[0064] 4: Printing device 4x: Image forming section 5: Optical scanning device 10: Image forming device 30: Sheet feeding mechanism 41: Photoreceptor 42: Charging device 43: Developing device 44: Transcription device 45: Drum cleaning device 46: Fixing device 50: Unit housing 51 :Light source 52: First lens 53: Aperture 54: Optical scanner 55: Second lens 56: Mirror 57: Third lens 58:Support mechanism 300: Transport path 441: Intermediate transfer belt 442: Primary transfer device 443: Secondary transfer device 444: Belt cleaning device 510: Light source set 530: Aperture unit B1: Beam light B2: Beam light set

Claims

1. a plurality of multi-beam light sources each emitting a plurality of light beam sets each including a plurality of light beams; a plurality of lenses through which the plurality of light beam sets pass, respectively; an aperture unit having a plurality of apertures that respectively transmit the plurality of light beam sets that have passed through the plurality of lenses; an optical scanner that reflects and scans the plurality of light beam sets that have passed through the plurality of apertures; an optical scanning device comprising: a support mechanism that supports the aperture unit and is capable of changing the position of the aperture unit in the direction of light travel from the plurality of lenses to the optical scanner and the angle of the aperture unit with respect to the direction of light travel.

2. A plurality of photoreceptors; an optical scanning device according to claim 1, wherein a plurality of light beam sets each consisting of a plurality of light beams are scanned on the surfaces of the plurality of photosensitive members to form electrostatic latent images on the surfaces of the plurality of photosensitive members; a plurality of developing devices for developing the electrostatic latent images on the surfaces of the plurality of photoreceptors into toner images; a transfer device that transfers the toner images on the surfaces of the plurality of photosensitive members onto a sheet.

Images