JP2000250369A - Dustproof device - Google Patents

Abstract

PROBLEM TO BE SOLVED: To obtain a dustproof device which is capable of preventing the degradation in image quality occurring in the adhesion of microobjects, such as dust and dirt. SOLUTION: The side wall 72 of a transportation system housing section in a casing is provided with a filter 74 in correspondence to a space between an inner bottom wall and a photosensitive material 70. Further, the section facing the filter 74 via the lower side of a window 68 of the side wall 76 is provided with a fan 78. The air in the transportation system housing section is discharged outside by operating the fan 78, by which a negative pressure is generated in the transportation system housing section and outdoor air is thereby taken into the transportation system housing section 2 via the filter 74. As a result, an air current passing the lower side of the window 68 parallel to the surface of the photosensitive material 70 is generated and the dust and dirt, etc., suspending in the transportation system housing section are entrained in the air current and discharged outside without the adhesion to the surface of the photosensitive material 70 or near to the window 68.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a dustproof device applied to an image forming apparatus such as a copying machine, a facsimile, and a laser printer.

[0002]

2. Description of the Related Art In recent years, for writing an image in a digital lab system or the like for recording an image recorded on a photographic film on a photosensitive material, an image forming apparatus that scans and exposes the photosensitive material using a light source that generates a laser beam is known. Widely used.

In this type of image forming apparatus, generally, R
(Red), G (green), and B (blue) are provided.
The laser light is modulated for each of G and B colors, these laser lights are deflected in the main scanning direction by a deflector such as a polygon mirror, and the photosensitive material is conveyed in the sub-scanning direction. The fθ lens, the cylindrical lens, the plane mirror, The photosensitive material is scanned and exposed through an optical system including a folding mirror and the like, and a color image is recorded.

In this type of image forming apparatus, an optical system such as the above-mentioned polygon mirror, fθ lens, cylindrical lens, plane mirror, folding mirror, etc., and a magazine for winding the photosensitive material, a roller for transporting the photosensitive material, etc. The interior of the housing that houses the system and the like is divided into an optical system housing part that houses the above-described optical system, and a transport system housing part that houses the magazines and rollers, etc. There is also an image forming apparatus of a type in which laser light is exposed from a side of an optical system accommodating section to a photosensitive material on a side of a transport system accommodating section through a slit-shaped opening.

[0005]

In the above-described image forming apparatus, if a minute object such as dust or dust floats inside the housing, the minute object may be on the exposed surface of the photosensitive material or on the optical surface. If it adheres to the system or to the above-mentioned opening or the like, there is a problem that exposure of the laser beam onto the photosensitive material is interrupted by the minute substance, and the quality of an image formed on the photosensitive material deteriorates.

SUMMARY OF THE INVENTION An object of the present invention is to provide a dustproof device capable of preventing a decrease in image quality due to minute objects such as dust and dirt in consideration of the above fact.

[0007]

According to a first aspect of the present invention, there is provided a housing for accommodating a photosensitive material therein, wherein a light beam is formed on the surface of the photosensitive material to form an image on the surface of the photosensitive material. A dustproof device that is applied to an image forming apparatus that forms an image on the surface of the light-sensitive material, and that discharges minute substances such as dust and dust floating in the housing to the outside of the housing, wherein An intake unit provided on the housing corresponding to the incident side, and capable of inhaling air from outside to inside the housing, facing the intake unit along a direction substantially parallel to the surface of the photosensitive material. The casing is provided with a negative thickness in the casing to exhaust air in the casing to the outside, and the exhaust causes the casing to enter the casing in a direction parallel to the surface of the photosensitive material. Exhaust means for generating a flowing airflow, That.

In the dustproof device having the above-described structure, when the exhausting means operates, the exhausting means forcibly exhausts the air in the housing to the outside, so that a negative pressure is generated in the housing and the negative pressure is applied to the surface of the photosensitive material in the housing. Outside air is taken in from the intake section facing the exhaust means in a substantially parallel direction. For this reason, an airflow is generated in the housing from the intake unit to the exhaust unit in a direction parallel to the surface of the photosensitive material. For this reason, minute objects such as dust and dust floating in the housing flow in the airflow without adhering to the surface of the photosensitive material in the housing and various components of the optical system, and are exhausted by the exhaust means. It is discharged outside.

According to a second aspect of the present invention, in the dustproof device according to the first aspect, an optical system housing portion for housing an optical system for forming an image of a light beam on the surface of the photosensitive material and the photosensitive material are housed. While partitioning the photosensitive material storage portion to be provided, and provided in the housing a wall portion formed with a through hole through which the light from the optical system storage portion passes to the photosensitive material storage portion side, more than the passage hole The apparatus is characterized in that the intake section and the exhaust section are provided so as to be opposed to each other via the photosensitive material storage section.

In the dustproof apparatus having the above structure, the photosensitive material is located between the wall separating the optical system housing and the photosensitive material housing, and the photosensitive material from the passage hole through which the light from the optical system housing passes. Since the intake unit and the exhaust unit are provided so as to be opposed to each other via the portion on the accommodation unit side, the airflow flowing between the intake unit and the exhaust unit flows through the passage hole side of the photosensitive material accommodation unit. For this reason, the air in the optical system housing flows into the photosensitive material housing through the passage hole, merges with the airflow, and is exhausted to the outside through the exhaust means. Therefore, no minute substance such as dust or dirt adheres to the passage hole and the vicinity thereof. In addition, when the air in the optical system housing portion flows toward the photosensitive material housing portion, minute substances such as dust and dirt floating in the optical system housing portion are guided to the photosensitive material housing portion side through the through holes, and are externally discharged from the exhaust means. Therefore, adhesion of minute substances such as dust and dirt to the optical system in the optical system housing portion is prevented.

[0011]

FIG. 2 is a schematic sectional view showing an example in which a dustproof device 73 according to an embodiment of the present invention is applied to a laser printer unit 12 of a digital laboratory system 10 as an image forming apparatus. FIG. 1 is a plan view schematically showing the laser printer unit 12.

As shown in FIG. 1, the laser printer unit 12 of the digital lab system 10 has a housing 14. As shown in FIG. 2, the housing 14 has an optical system housing portion 20 above the middle bottom wall 16 as a wall portion and a transport system housing portion 22 as a photosensitive material housing portion below. The upper part of the optical system housing 22 is closed by the cover 18. FIG. 1 shows the optical system housing section 20 above the inner bottom wall 16.

As shown in FIG. 1, a plurality of laser light sources 24, 26, and 28 are provided on the inner bottom wall 16 as light sources. The laser light source 24 is configured to include a semiconductor laser that emits a laser beam having an R wavelength (for example, 680 nm). On the other hand, the laser light source 26 reduces the semiconductor laser and the laser light emitted from this semiconductor laser by half.
And a wavelength conversion element that converts the laser light into a laser light having a wavelength of λ. The oscillation wavelength of the semiconductor laser is set such that a laser light having a wavelength of G (for example, 532 nm) is emitted from the wavelength conversion element. I have. The laser light source 28
Also includes a semiconductor laser and a wavelength conversion element for converting the laser light emitted from the semiconductor laser to a laser light having a half wavelength, and the wavelength conversion element outputs a wavelength of B (for example, 475 nm). The oscillation wavelength of the semiconductor laser is set so that the laser light is emitted. In the present embodiment, the above laser light sources 24, 26,
Although a semiconductor laser is used for 28, another laser such as a solid-state laser may be used instead of this semiconductor laser.

The image data read by the scanner unit of the digital lab system 10 (not shown) is converted into a predetermined digital signal by the image processing unit and transmitted to these laser light sources 24 to 28.
4 to 28 emit laser light corresponding to this signal at a predetermined timing.

On the laser light emitting side of these laser light sources 24-28, collimator lenses 30 are arranged corresponding to the laser light sources 24-28, respectively. On the opposite side, acousto-optic conversion elements 32 are arranged, respectively, and the laser light passing through each collimator lens 30 is incident on the acousto-optic conversion element 32 corresponding to each collimator lens 30. Each of the acousto-optic conversion elements 32 is arranged so that the incident laser light passes through the acousto-optic medium, and is connected to an AOM (acousto-optic conversion element) driver (not shown). When a high-frequency signal is input from the AOM driver to each of the acousto-optic conversion elements 32, an ultrasonic wave corresponding to the high-frequency signal propagates in the acousto-optic medium, and the acousto-optic effect acts on the laser light transmitted through the acousto-optic medium. Diffraction occurs, and a laser beam having an intensity corresponding to the amplitude of the high-frequency signal is emitted from the acousto-optic conversion element 32 as diffracted light.

Through holes are formed in the side walls 34 of the laser printer section 12 which are opposed to each other on the diffracted light emission side of the acousto-optic conversion element 32, and a window glass 36 is provided in these through holes. Each diffracted light enters the inside of the section 12. On the opposite side of the acousto-optic conversion element 32 via each window glass 36 inside the laser printer unit 12, a reflecting mirror 38 is arranged corresponding to each acousto-optic conversion element 32. Is reflected in a predetermined direction.

FIG. 3 shows these reflecting mirrors 3.
8 is an enlarged perspective view of one of the reflecting mirrors 38, and FIG. 4 is a side view of the reflecting mirror 38.
As shown in FIGS. 3 and 4, the reflecting mirror 38 includes a reflecting mirror main body 40 substantially constituting a reflecting mirror and a pair of supporting legs 42 as supporting means for supporting the main body. Each support leg 42 is disposed so as to sandwich the reflecting mirror body 40 from both sides in the width direction.
Is fixed to the inner bottom wall 16 by screwing. Also,
A reflector body 4 is provided at an intermediate portion in the height direction of these support legs 42.
Shafts 44 protruding from the longitudinal center portions at both ends in the width direction of 0 are penetrated. Have been.

As described above, the reflecting mirror body 40 (reflecting mirror 38) reflects the diffracted light incident through the window glass 36, but the reflecting mirror body 40 is diffracted around the shaft 44 by the rotation position. The light reflection direction changes.

Further, the side wall 34 on the back side of the reflecting mirror body 40 is provided.
Is formed with a screw hole 46 penetrating along its thickness direction. The screw hole 46 is located further above the shaft 44 penetrating the reflector main body 40 and below the upper end of the reflector main body 40. , An adjusting screw 48 as an operation screw and a limiting screw is screwed. Adjustment screw 4
8 is a laser printer unit 12 that passes through the screw hole 46
The reflector has a sufficient length to protrude inside and outside, and a tip portion thereof is a spherical portion 50 protruding toward the back side of the reflector main body 40. On the other hand, the proximal end of the adjusting screw 48 protruding outside from the side wall 34 is, for example,
An adjusting tool (not shown) such as a hexagon wrench can be engaged. Basically, the adjusting screw 48 is rotated by rotating the adjusting tool around the adjusting screw 48 by engaging such an adjusting tool. By rotating the adjusting screw 48 about its own axis, the adjusting screw 48 can be rotated along its longitudinal direction by the pitch of the adjusting screw 48 and the screw hole 46 according to the amount of rotation. Can be displaced.

On the other hand, below the screw hole 46 of the side wall 34, a screw hole 52 penetrating the side wall 34 along the thickness direction thereof.
Are formed. The screw hole 52 is located further below the shaft 44 penetrating the reflector main body 40 and above the lower end of the reflector main body 40.
2, an operating means and a limiting means, more narrowly, an adjusting screw 54 as an operating screw and a limiting screw are screwed. The adjusting screw 54 has a length sufficient to penetrate the screw hole 52 and still protrude into and out of the laser printer unit 12, and the distal end thereof is directed toward the rear side of the reflecting mirror body 40. The overhanging spherical portion 56 is provided. On the other hand, the base end of the adjusting screw 54 projecting from the side wall 34 to the outside can be engaged with an adjusting tool (not shown) such as a hexagon wrench. By rotating the adjustment tool around its own axis by rotating the adjustment tool around the adjustment screw 54 by engaging with the, the adjustment screw 54 is rotated around its own axis, and the amount of rotation is adjusted according to the amount of rotation. Thus, the adjusting screw 54 can be displaced along the longitudinal direction by the pitch of the adjusting screw 54 and the screw hole 52.

On the diffracted light reflecting side of the reflecting mirror 38 having the above-described structure, a spherical lens 58 is provided corresponding to each of the reflecting mirrors 38, and on the opposite side of the corresponding reflecting mirror 38 via each of the spherical lenses 58. Is provided with a cylindrical lens 60. Further, a polygon mirror 62 as a deflecting unit is disposed on the opposite side of the corresponding spherical lens 58 via each cylindrical lens 60. Polygon mirror 62
Has a regular polygonal shape in plan view, and rotates around its center by the driving force of a driving unit (not shown). The optical axis of the above-described diffracted light from the cylindrical lens 60 is set to the radial direction of the polygon mirror 62, and the diffracted light from the cylindrical lens 60 is
2 is incident on the outer peripheral surface. The outer peripheral surface of the polygon mirror 62 is a mirror surface, and the incident diffracted light is reflected by the outer peripheral surface of the polygon mirror 62.

An fθ lens 64 as convergence means is disposed on the diffracted light reflecting side of the polygon mirror 62.
A plurality of plane mirrors 66 are disposed on the opposite side of the polygon mirror 62 via the lens 64, and the fθ lens 6
The diffracted light that has passed through 4 is directed downward in the height direction of laser printer unit 12 by reflection at plane mirror 66, and passes through window 68 as a rectangular through-hole formed in middle bottom wall 16 of housing 14. pass.

As shown in FIG. 2, a photosensitive material 70 is disposed in the transfer system housing section 22 below the middle bottom wall 16 of the housing 14. The photosensitive material 70 is arranged so that the width direction thereof is the longitudinal direction of the window 68 described above.
The diffracted light transmitted through is irradiated on the photosensitive material 70. Here, the diffracted light scans the photosensitive material 70 along the width direction by rotating the above-described cylindrical lens 60.

One end of the photosensitive material 70 in the longitudinal direction is accommodated in a magazine (not shown) in a wound state, and is conveyed along the longitudinal direction at a predetermined speed by conveying means such as conveying rollers 80.

Also, as shown in FIG.
On the side wall 72 opposite to the side wall 34 and at one end in the longitudinal direction of the photosensitive material 70, a filter 74 constituting a dustproof device 73 is provided as an intake unit. Prevents the entry of minute objects such as dust.

On the other hand, a fan 78 constituting a dustproof device 73 is provided as an exhaust means on the side wall 76 on the side downstream of the photosensitive material 70 (the other end in the longitudinal direction) and opposite to the side wall 72. The fan 78 operates and rotates, so that the inner bottom wall 16 is rotated.
The inside of the housing 14 on the lower side is exhausted to the outside of the housing 14, whereby a negative pressure is generated inside the housing 14, so that the outside air flows from the filter 74 into the housing 14. Inhaled. Accordingly, in the operating state of the fan 78, an airflow along the direction of the arrow W in FIG.

Next, the operation and effect of this embodiment will be described.

Laser light emitted from the laser light sources 24 to 28 in the laser printer unit 12 of the digital lab system 10 passes through the collimator lens 30 and enters the acousto-optic conversion element 32. Ultrasonic waves corresponding to the high-frequency signal input to the optical conversion element 32 propagate into the acousto-optic medium, and laser light transmitted through the acousto-optic medium is emitted as diffracted light corresponding to the amplitude of the high-frequency signal. The diffracted light enters the laser printer unit 12 through the window glass 36 and is reflected by the reflecting mirror body 40 of the reflecting mirror 38.

Here, the reflecting mirror body 40 is rotatable around the shaft 44, and the angle of incidence of the diffracted light on the reflecting surface of the reflecting mirror body 40 varies depending on the rotating state.
The reflection angle is also different, and as a result, it changes along the sub-scanning direction of the photosensitive material 70 (the longitudinal direction of the photosensitive material 70). However, when the spherical portions 50 and 56 of the adjusting screws 48 and 54 are in contact with the back surface of the reflector main body 40, the rotation of the reflector main body 40 around the shaft 44 is limited.
The incident angle and the reflection angle of the diffracted light do not change carelessly.

In this state, for example, first, an adjusting tool (not shown) is engaged with the base end of the adjusting screw 54 to adjust the adjusting screw 5.
When the adjusting screw 54 is rotated around its own axis to move the adjusting screw 54 to the outside of the side wall 34 along its own axis, the spherical portion 56 of the adjusting screw 54 Move away from the back. Therefore, in this state, the rear surface of the reflecting mirror body 40 is
The back of the reflector body 40 is adjusted from the position where
Of the reflecting mirror body 4 until it comes into contact with the spherical portion 56 of the reflecting mirror body 4
0 is rotatable around the shaft 44.

Then, from this state, an adjusting tool (not shown) is engaged with the base end of the adjusting screw 48 to rotate around the adjusting screw 48, and the adjusting screw 48 is rotated around its own axis to adjust the adjusting screw 48. Is moved to the inside of the laser printer unit 12 along its own axis.
0 presses the back surface of the reflector main body 40 to rotate the reflector main body 40 around the shaft 44. When the adjusting tool is rotated and the rear surface of the reflecting mirror body 40 is continuously pressed by the spherical portion 50 of the adjusting screw 48, the rear surface of the reflecting mirror body 40 comes into contact with the spherical portion 56 of the adjusting screw 54, and the further reflecting mirror body The rotation of 40 is limited by spherical portion 56.

On the contrary, if the adjusting screw 48 is moved to the outside of the side wall 34 by rotating the adjusting tool and then the adjusting screw 54 is moved to the inside of the laser printer section 12 by rotating the adjusting tool, The pressing force from the spherical portion 56 of the adjusting screw 54 causes the reflecting mirror main body 40 to rotate around the shaft 44 in a direction opposite to the above-described rotation direction.

As described above, the present digital lab system 1
In the laser printer unit 12 of No. 0, the adjusting screw 4
The angle of incidence of the diffracted light on the reflecting mirror main body 40 and the angle of reflection of the diffracted light on the reflecting mirror main body 40 can be adjusted by appropriately rotating the adjusting screw 8 and the adjusting screw 54, and the imaging of the diffracted light on the photosensitive material 70 can be performed. The position can be adjusted. Moreover, the adjusting screws 48, 54
Can be rotated from the outside of the side wall 34. Therefore, even after the apparatus is assembled to some extent and a lid (not shown) is attached to the housing 14 and the inside of the housing 14 is closed, the angle of incidence of the diffracted light on the reflecting mirror body 40. In addition, since the angle of reflection of the diffracted light by the reflecting mirror body 40 can be adjusted, the adjustment work in the manufacturing process and maintenance becomes extremely easy. Further, each of the adjusting screws 48, 54 can move along its own axis by only one pitch per rotation. Therefore, extremely fine angle adjustment of the reflecting mirror main body 40 is possible, and in this sense, adjustment work in the manufacturing process and maintenance is extremely easy.

Next, the diffracted light reflected by the reflecting mirror body 40 of the reflecting mirror 38 passes through the spherical lens 58 and the cylindrical lens 60 and is incident on the side surface of the rotating fθ lens 64. The diffracted light reflected on the side surface of the fθ lens 64 passes through the fθ lens 64,
The laser beam is reflected at 6 and its optical axis is directed downward in the height direction of the laser printer unit 12. The diffracted light whose optical axis is directed downward in the height direction passes through the window 68 of the inner bottom wall 16 and passes through the inner bottom wall 16.
Is formed on the photosensitive material 70 below the photosensitive material 70, whereby a latent image is formed on the photosensitive material 70 and an image is formed on the photosensitive material 70 by developing the photosensitive material 70.

Here, at least in the operating state of the apparatus, the fan 78 is operated. When the fan 78 is operated, a negative pressure is generated in the transport system housing unit 22.
Outside air is sucked from the filter 74 and is directed from the filter 74 side to the fan 78 side under the inner bottom wall 16 (that is,
A flowing airflow (in the direction of arrow W in FIG. 4) is generated. For this reason, minute substances such as dust and dirt that cannot be captured by the filter 74 and have entered the transport system housing portion 22 of the housing 14 are exposed to the photosensitive material 70.
Fan 7 on air flow without collecting on top or near window 68
8 to the outside.

Further, since the internal space of the optical system housing section 20 closed by the cover 18 communicates with the transport system housing section 22 through the window 68, the above-described airflow is generated, or When a negative pressure is generated in the transport system housing unit 22, the air inside the optical system housing unit 20 is guided to the transport system housing unit 22 side and joins the airflow on the transport system housing unit 22 side. For this reason, minute substances such as dust and dirt floating in the housing 14 on the optical system housing 20 side are guided to the transport system housing 22 through the window 68, and are also taken from the fan 78 by airflow. It is discharged outside. For this reason, each member constituting the optical system (that is, the collimator lens 30)
And the reflection mirror 38, the polygon mirror 62, etc.) can be prevented from adhering fine particles such as dust and dirt, and the image quality of the photosensitive material 70 due to the adherence of these fine particles to members constituting the optical system can be reduced. Drop can be prevented.

[0037]

As described above, according to the first aspect of the present invention, it is possible to prevent the adhesion of minute substances such as dust and dust floating in the housing to the surface of the photosensitive material and various components of the optical system. The quality of the image formed on the photosensitive material can be ensured.

Further, according to the present invention, minute substances such as dust and dust floating in the photosensitive material accommodating portion of the housing can be discharged to the outside, so that the floating matter adheres to the photosensitive material and adheres to the wall. Adhesion of floating substances such as dust and dirt near the passage hole formed in the wall to allow light to pass through, and floating substances such as dust and dirt floating in the optical system storage section through the photosensitive material storage section Can be discharged outside. Therefore, the quality of the image formed on the photosensitive material can be ensured.

[Brief description of the drawings]

FIG. 1 is a schematic plan view of a laser printer unit of a digital laboratory system to which a scanning optical system according to an embodiment of the present invention has been applied.

FIG. 2 is a schematic cross-sectional view of a laser printer unit of a digital laboratory system to which the scanning optical system according to one embodiment of the present invention is applied.

FIG. 3 is an exploded perspective view showing a configuration of a reflecting mirror.

FIG. 4 is a side view showing a configuration of a reflecting mirror.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 10 Digital laboratory system (image forming apparatus) 14 Housing 16 Middle wall part (wall part) 20 Optical system accommodation part 22 Transport system accommodation part (photosensitive material accommodation part) 73 Dustproof device 74 Filter (intake part) 78 Fan (exhaust means) )

Continuation of the front page F term (reference) 2C061 AP03 AP04 AQ06 AR01 BB08 BB35 2H027 JA03 ZA07 2H071 EA04 5C051 AA02 CA07 DB02 DB22 DB24 DB30 DB31 DC07 9A001 KK42 LL00

Claims (2)

[Claims] 1. A housing for housing a photosensitive material therein,
The present invention is applied to an image forming apparatus that forms an image on the surface of the photosensitive material by forming a light beam on the surface of the photosensitive material, and removes small particles such as dust and dust floating inside the housing outside the housing. A dust-proof device that is provided in the housing in correspondence with the light-incident side of the surface of the photosensitive material relative to a surface of the photosensitive material, and that is capable of sucking air from outside to inside of the housing, The housing is provided in the housing in a direction substantially parallel to the surface of the housing so as to face the air intake portion, and generates a negative thickness in the housing to exhaust air in the housing to the outside, Exhaust means for generating an airflow flowing in a direction parallel to the surface of the photosensitive material in the housing. 2. An optical system accommodating section for accommodating an optical system for imaging a light beam on a surface of the photosensitive material, and a photosensitive material accommodating section for accommodating the photosensitive material. A wall having a passage hole through which the light beam passes to the photosensitive material storage section side is provided in the housing, and the suction section and the suction section are opposed to each other via the photosensitive material storage section side of the passage hole. The dustproof device according to claim 1, further comprising an exhaust means.