JP5610143B2 - Optical scanning apparatus and image forming apparatus - Google Patents

Description

  The present invention relates to an optical scanning device for performing optical writing in a printer or the like, and an image forming apparatus equipped with the optical scanning device.

Image forming apparatuses such as laser printers, laser facsimiles, and digital copying machines include an optical scanning device for writing a latent image on a photoconductor.
In recent years, there has been a demand for higher image quality in image forming apparatuses. However, in optical scanning devices, white streaks and uneven color are caused by contamination of dust, toner, or the like on the laser light emitting portion and blocking the laser light. As a result, the image quality deteriorates.

  On the other hand, with the demand for miniaturization of image forming apparatuses, the arrangement of the optical writing unit (optical scanning apparatus) in the image forming apparatus is diversified, and is arranged in the horizontal direction or below the image carrier. May be. With such a configuration, there is a problem that dirt in the image forming apparatus is likely to adhere to a transparent member such as dust-proof glass provided at the laser emission port.

  It is desirable that dirt on the dust-proof glass be cleaned promptly and automatically. For this purpose, for example, a method has been proposed in which a shutter member that shields and opens the dust-proof glass member by driving a motor is provided, and dirt is removed by using the movement of the shutter member (see, for example, Patent Documents 1 and 2).

  In Patent Document 1, a cleaning member is attached to the shutter member, and the dust adhering to the outer peripheral surface of the dust-proof glass is automatically cleaned by the cleaning member by moving the shutter member before and after the start of the image forming operation. In addition, a technique for preventing the adhesion of dust by positioning the shutter member at the covering position after the image forming operation is completed is described.

  A conventional shutter member provided in an image forming apparatus has a mechanism that operates by transmitting the power of a motor by a worm gear. Therefore, the protrusion on the gear pushes the shutter member to operate the shutter member, and the cleaning member such as a nonwoven fabric attached to the shutter member moves on the dust-proof glass, and the dust-proof glass is cleaned.

  However, the cleaning mechanism provided in the conventional image forming apparatus has a problem that the cleaning power is weak and cannot be completely removed when a large amount of toner adheres to the dust-proof glass. There is a problem that dirt outside the range of the cleaning member that moves with the opening / closing operation cannot be removed.

  Therefore, the present invention provides an optical scanning device provided with a cleaning mechanism that can be reliably wiped even when a large amount of toner or dust adheres to the dust-proof glass or is extensively contaminated, and an image provided with the optical scanning device. An object is to provide a forming apparatus.

The present invention provided to solve the above problems is as follows.
[1] In an optical scanning device that emits a light beam from a light source through an exit port provided with a dustproof member and optically scans a surface to be scanned.
A shutter member disposed so as to cover the upper surface of the dust-proof member;
The shutter member performs cleaning member at one end, Rutotomoni includes a blade member at the other end, the cleaning operation for wiping foreign matter off operation and the dustproof member upper surface for shielding and open the exit port by a driving mechanism,
During the opening and closing operation, the cleaning member wipes off foreign matter on the upper surface of the dust-proof member,
During the cleaning operation, the cleaning member and the blade member wipe away foreign matter on the upper surface of the dust-proof member,
The cleaning operation is performed by rotating the motor of the drive mechanism in a direction different from that during the opening / closing operation.
[2] The drive mechanism includes the motor, a worm gear, and a protruding member formed on the worm wheel of the worm gear,
The shutter member includes an opening / closing operation contact portion that contacts the protruding member during the opening / closing operation, and a cleaning operation contact portion that contacts the protruding member during the cleaning operation. The optical scanning device according to [1].
[3] The optical scanning device according to [2], wherein a length from a base portion of the shutter member to the cleaning operation contact portion is longer than a length from the opening / closing operation contact portion. is there.
[4] The protruding member includes a rotatable cylindrical cover, and the cylindrical cover is in contact with the opening / closing operation contact portion or the cleaning operation contact portion of the shutter member. The optical scanning device according to [2] or [3], wherein the optical scanning device rotates around a protruding member as an axis.
[5] The optical scanning device according to any one of [1] to [4], wherein the blade member is made of a highly elastic resin.
[6] The opening / closing operation contact portion and the cleaning operation contact portion of the shutter member have the same curvature as an arc when the projecting member rotates. 5]. The optical scanning device according to any one of 5).
[7] The optical scanning device according to any one of [1] to [6], further including a function of performing a cleaning operation according to an instruction from an external input.
[8] An image forming apparatus comprising the optical scanning device according to any one of [1] to [7].

As an effect of the present invention, according to the first aspect of the present invention, the upper surface of the dust-proof member can be covered in an optical scanning device that emits a light beam from a light source from an emission port provided with a dust-proof member and optically scans the surface to be scanned a shutter member disposed on said shutter member, cleaning member at one end, Rutotomoni includes a blade member at the other end, the foreign matter of the dustproof member top surface and the opening and closing operation of the shield and open the exit port by a drive mechanism The cleaning member wipes off foreign matter on the upper surface of the dust-proof member during the opening and closing operation, and the cleaning member and the blade member wipe off foreign matter on the upper surface of the dust-proof member during the cleaning operation. be one, and the cleaning operation, the motor of the drive mechanism is carried out by rotating in a direction different from the time of the closing operation, when cleaning operation the blade The member can be operated with different strokes, and the cleaning member and blade member wipe the dust-proof glass, so even if a large amount of toner or dust adheres to the dust-proof glass, or even if it is extensively contaminated, it is wiped reliably be able to.
According to a second aspect of the present invention, in the optical scanning device according to the first aspect, the drive mechanism includes the motor, a worm gear, and a protruding member formed on a worm wheel of the worm gear, The shutter member includes an opening / closing operation contact portion with which the protruding member contacts during the opening / closing operation and a cleaning operation contact portion with which the protruding member contacts during the cleaning operation. By switching, the opening / closing operation and the cleaning operation can be switched.
According to a third aspect of the present invention, in the optical scanning device according to the second aspect, the length from the base portion of the shutter member to the cleaning operation contact portion is longer than the length from the opening / closing operation contact portion. Therefore, when the cleaning operation contact portion comes into contact with the protruding member, the distance to push out the shutter member becomes longer, and the range over which the dust-proof member can be wiped is widened.
According to a fourth aspect of the present invention, in the optical scanning device according to the second or third aspect, the projecting member includes a rotatable cylindrical cover, and the cylindrical cover is used for the opening / closing operation of the shutter member. When the abutting portion or the abutting portion for cleaning operation abuts, the protrusion-like member rotates around the shaft, so that the generation of friction can be reduced and the life of the apparatus can be extended.
According to a fifth aspect of the present invention, in the optical scanning device according to any one of the first to fourth aspects, since the blade member is made of a highly elastic resin, the contact with the dustproof member is good and during cleaning. The wiping ability is high, and fine toner and dust can be removed.
According to a sixth aspect of the present invention, in the optical scanning device according to any of the second to fifth aspects, the opening / closing operation contact portion and the cleaning operation contact portion of the shutter member are the protruding members. Since it has the same curvature as the circular arc when the motor rotates, the control of the movement position of the shutter member can be stabilized even when the motor control varies, and a stable opening / closing operation and cleaning operation can be performed.
According to the seventh aspect of the present invention, the optical scanning device according to any one of the first to sixth aspects has a function of performing a cleaning operation in response to an instruction from an external input. For example, when a problem occurs, the user can manually perform input at any time to execute a cleaning operation to remove dirt and restore image quality.
According to the eighth aspect of the present invention, since the image forming apparatus includes the optical scanning device according to any one of the first to seventh aspects, a large amount of toner or dust adheres to the dust-proof glass, or extensive contamination occurs. Even in such a case, it can be wiped off reliably, and high-quality image formation can be maintained.

1 is a cross-sectional view illustrating an outline of an embodiment of an image forming apparatus including an example of an optical scanning device of the present invention. 1 is a schematic view centering on an optical scanning device in an image forming apparatus of the present invention. FIG. 6 is a perspective view showing the drive mechanism of the optical scanning device of the present invention, and the vicinity of the cleaning operation contact portion and the opening / closing operation contact portion of the shutter member. It is the schematic which shows the motion of the shutter member by the drive mechanism at the time of opening / closing operation | movement. It is the schematic which shows the motion of the shutter member by the drive mechanism at the time of cleaning operation. It is the schematic which shows the motion of the shutter member on a dust-proof member at the time of opening / closing operation | movement. It is the schematic which shows the motion of the shutter member on a dust-proof member at the time of cleaning operation | movement. It is an electron micrograph explaining the magnitude | size of the paper dust which is the stain | pollution | contamination adhering on a dustproof member, and a toner.

  Hereinafter, an optical scanning device and an image forming apparatus according to the present invention will be described with reference to the drawings. The present invention is not limited to the embodiments described below, and other embodiments, additions, modifications, deletions, and the like can be changed within a range that can be conceived by those skilled in the art, and any aspect is possible. As long as the functions and effects of the present invention are exhibited, the scope of the present invention is included.

  FIG. 1 is a cross-sectional configuration diagram illustrating an outline of an image forming apparatus including an example of an optical scanning device according to the present invention. The full-color printer 50 shown in this figure is a so-called quadruple tandem image forming apparatus. Four image forming units (for four colors) are arranged facing the transfer belt 51, and toner images on the respective photoreceptors 9 are arranged. Are transferred onto the transfer belt 51 and transferred onto a recording material fed from the paper supply unit 52, and a full-color image can be obtained in a short time.

  The transfer belt 51 is rotated counterclockwise in the drawing. Four image forming units (for four colors) centering on the photosensitive drum 9 are arranged in parallel below the transfer belt 51. The configuration of each color image forming unit is the same, and only the color of the toner used is different. In this example, each color image forming unit forms an image using each color toner of cyan, magenta, yellow, and black (marks indicating the colors of C, M, Y, and K are written in the photosensitive drums 9a to 9d). Is done. An optical scanning device 15 is disposed below the image forming unit. The recording material fed from the paper feeding unit 52 is sent out in timing with the toner image on the transfer belt 51 by the registration roller 53, and the toner on the transfer belt 51 is operated by the transfer roller 54 as a transfer unit. The image is transferred to the recording material. The toner image on the recording material is fixed by the fixing device 55, and the recording material is discharged to the discharge tray 57 by the discharge roller 56 and stacked.

FIG. 2 is an enlarged view showing in detail the vicinity of the optical scanning device. As shown in FIG. 2, the optical scanning device includes a two-stage polygon mirror 1 that is an optical deflector, a dustproof member (dustproof glass) 2, an fθ lens 3, a mirror group, and the like. The upper cover 11 for sealing the housing and the lid 10 for the optical deflector (polygon mirror) portion. A shutter member 14 is slidably and integrally mounted on the upper cover 11. The shutter member 14 is provided with a cleaning member 16 made of a nonwoven fabric or the like at one end and a blade member at the other end.
In FIGS. 1 and 2, the optical path to each photoconductor is denoted by reference numerals La, Lb, Lc, and Ld.

  The polygon mirror 1 has a reflection mirror on the side of a regular polygon, is rotated at a high speed by a polygon motor (not shown), and deflects and scans laser light from a light source (not shown). The fθ lens 3 is an optical element that changes the equiangular motion of the beam scanning by the polygon mirror 1 into a uniform linear motion. The mirror group is an optical element that guides the laser light to each of the photoconductors 9a to 9d disposed above the optical scanning device. The dust-proof member 2 prevents dust and the like from falling into the optical housing 13.

  The shutter member 14 reciprocates on the dust-proof member 2 by a driving mechanism, and performs an opening / closing operation for shielding and opening the emission port and a cleaning operation for wiping off foreign matter on the upper surface of the dust-proof member. The drive mechanism includes a motor (not shown), a worm 18 of a worm gear, and a protruding member 17b formed on the worm wheel 17a of the worm gear. It has been converted to moving motion. The protruding member 17b on the wheel 17a contacts the opening / closing operation contact portion 14c during the opening / closing operation of the shutter member, contacts the cleaning operation contact portion 14b during the cleaning operation, and pushes them out by rotation of the motor. As a result, the shutter member 14 operates.

FIG. 3 is a perspective view of the main part of the drive mechanism of the optical scanning device of the present invention. A cleaning operation contact portion 14b and an opening / closing operation contact portion 14c of the shutter member 14, a worm gear worm 18 and a protruding member 17b formed on the worm gear worm wheel 17a are shown.
The protruding member 17b includes a rotatable cylindrical cover, and the cylindrical cover is protruded when it contacts the opening / closing contact 14c or the cleaning contact 14b of the shutter member 14. Rotate around the axis.

4 and 5 are schematic views as seen from the upper surface of the mechanism for driving the shutter member 14. FIG. 4 shows an opening / closing operation, and FIG. 5 shows a cleaning operation.
As shown in FIG. 4, the length L3 from the base portion 14a of the shutter member to the cleaning operation contact portion 14b is longer than the length L4 to the opening / closing operation contact portion 14c.
Further, the cleaning operation contact portion 14b and the opening / closing operation contact portion 14c have the same curvature as an arc when the protruding member 17b rotates.

  As shown in FIG. 4, during the opening / closing operation, that is, during image formation, the protruding member 17b rotates counterclockwise. The projecting member 17b comes into contact with the contact portion 14c for opening / closing operation, pushes up as shown in FIGS. 4A to 4B, and stops at the highest position in the center, so that the shutter member 14 is opened. Position.

  As shown in FIG. 5, during the cleaning operation, the protruding member 17b rotates clockwise. The projecting member 17b comes into contact with the cleaning operation contact portion 14b, performs a push-up operation as shown in FIGS. 5A to 5B, and stops at the highest position in the center, whereby the shutter member 14 is opened. Position.

As shown in FIG. 5, when the motor rotates in the reverse direction to the normal opening / closing operation shown in FIG. 4, the protruding member 17b also rotates in the reverse direction, and the shutter member push-out portion that does not contact during the normal opening / closing operation. The movement which pushes out is produced. Only the cleaning member 16 made of a nonwoven fabric or the like provided at one end of the shutter member 14 is used to push out the shutter member 14 at the stroke L2 at the cleaning operation shown in FIG. 5 which is larger than the stroke L1 at the opening / closing operation shown in FIG. First, the blade member 15 provided at the other end slides while pressing on the dust-proof member 2, and the dust-proof member 2 can be wiped with the nonwoven fabric and the blade member.
In particular, the blade member 15 is preferably made of, for example, a resin having elasticity such as rubber. By wiping the dust-proof member 2 with the blade member of such a material, toner having a small particle diameter that cannot be wiped with a nonwoven fabric is also obtained. Can be cleaned.

6 and 7 are schematic views showing the movement of the shutter member 14 on the dust-proof member 2 as viewed from the side, FIG. 6 shows an opening / closing operation, and FIG. 7 shows a cleaning operation.
As shown in the upper part of FIG. 6, for example, dirt such as dust 21, paper powder 22, and toner 23 may adhere to the dust-proof member 2. During normal opening and closing operations, as shown in the lower part of FIG. 6, the cleaning member 16 provided with a nonwoven fabric or the like moves on the dust-proof member 2 and wipes it, so that large dirt such as dust 21 and paper dust 22 is removed. The However, fine dirt having a small particle diameter such as the toner 23 can be wiped off to some extent, but complete removal is difficult.
On the other hand, as shown in FIG. 7, during the cleaning operation, the blade member 15 wipes the dust-proof member 2 so that dirt such as the toner 23 that cannot be wiped by the nonwoven fabric can be removed.

FIG. 8 is an electron micrograph showing the size of the dirt, paper dust 22 and toner 23 schematically shown in FIGS. 6 and 7.
The paper dust is about 50 μm in size, but the toner particle size is about 6.8 μm.

  The cleaning operation may be set in advance by a control device or the like so as to be automatically performed at an arbitrary execution interval, and may be provided with a function of performing the cleaning operation by an instruction from an external input. For example, when a defect such as a white streak occurs in the image, the cleaning operation may be performed by manual input by the user at any time.

  As described above, the optical scanning device of the present invention pushes out the contact portion of the shutter member that is not originally in contact with the normal opening and closing operation of the motor of the drive mechanism during the cleaning operation, The shutter member is pushed out with a stroke larger than the opening / closing operation, and the blade member provided at the end of the shutter member not provided with the cleaning member slides while pressing on the dust-proof glass. As a result, even when a large amount of toner or dust adheres to the dust-proof glass or when it is extensively contaminated, the dirt can be reliably wiped off, and the image forming apparatus equipped with the optical scanning device can produce a high-quality image. Can be provided.

1 Optical deflector (polygon scanner)
2 Dust-proof material (dust-proof glass)
DESCRIPTION OF SYMBOLS 3 f (theta) lens 9 Photosensitive drum 10 Optical deflector cover 11 Optical housing cover 13 Optical housing 14 Shutter member 14a Shutter member base 14b Opening / closing operation contact part 14c Cleaning operation contact part 15 Blade member 16 Cleaning member 17a Warm wheel 17b Protruding member 18 Warm

JP 2005-329622 A JP 2005-215295 A

Claims (8)

In an optical scanning device that emits a light beam from a light source from an emission port provided with a dustproof member and optically scans a surface to be scanned,
A shutter member disposed so as to cover the upper surface of the dust-proof member;
The shutter member performs cleaning member at one end, Rutotomoni includes a blade member at the other end, the cleaning operation for wiping foreign matter off operation and the dustproof member upper surface for shielding and open the exit port by a driving mechanism,
During the opening and closing operation, the cleaning member wipes off foreign matter on the upper surface of the dust-proof member,
During the cleaning operation, the cleaning member and the blade member wipe away foreign matter on the upper surface of the dust-proof member,
The cleaning operation is performed by rotating a motor of the drive mechanism in a direction different from that during the opening / closing operation. The drive mechanism comprises the motor, a worm gear, and a protruding member formed on the worm wheel of the worm gear,
The shutter member includes an opening / closing operation contact portion that contacts the protruding member during the opening / closing operation, and a cleaning operation contact portion that contacts the protruding member during the cleaning operation. The optical scanning device according to claim 1.   The optical scanning device according to claim 2, wherein a length from a base portion of the shutter member to the cleaning operation contact portion is longer than a length from the opening / closing operation contact portion.   The projecting member includes a rotatable cylindrical cover, and the projecting member is in contact with the opening / closing operation contact portion or the cleaning operation contact portion of the shutter member. The optical scanning device according to claim 2, wherein the optical scanning device rotates about the axis.   The optical scanning device according to claim 1, wherein the blade member is made of a highly elastic resin.   6. The opening / closing operation contact portion and the cleaning operation contact portion of the shutter member have the same curvature as an arc when the protruding member rotates. The optical scanning device described.   The optical scanning device according to claim 1, further comprising a function of performing a cleaning operation according to an instruction from an external input. An image forming apparatus comprising the optical scanning device according to claim 1.