JP2001215434A - Optical scanner - Google Patents

Abstract

PROBLEM TO BE SOLVED: To obtain an optical scanner which has an angle regulating mechanism of a reflection mirror and surely suppresses the bending vibration of a reflection mirror even with the constitution corresponding to a plurality of resolution and printing speeds. SOLUTION: The optical scanner 10 turnably supports the reflection mirror 26 by a first supporting section 42, a second supporting section 44 and a projecting part 36 of a lower supporting plate 30 and energizes a mirror back 26B side by a spring 50. The angle oaf a reflection surface 26A is regulated by a regulating screw 48 of a regulating bracket. The lower supporting plate 30 for supporting a mirror base surface 26C is changed in its mounting direction by removing a screw 32, by which the position of the projecting apt 36 may be changed. As a result, the supporting point of the reflection mirror 26 is changed and the resonance frequency at which the reflection mirror 26 induces resonance with a vibration source may be changed.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an optical scanning apparatus used in an electrophotographic apparatus such as a laser printer or a digital copying machine for recording an image by scanning and exposing a light beam on a scanned object in accordance with image information. About.

[0002]

2. Description of the Related Art The configuration of a conventional optical scanning device will be described with reference to FIG.

An optical scanning device 100 includes a light source device 104 for emitting a light beam 102 containing information, and a polygon motor 1 for deflecting the emitted light beam 102 in a predetermined direction.
06, a reflecting mirror 112 for guiding the deflected light beam 102 through the imaging lens system 108 to the object to be scanned 110, and a housing 114 for accommodating and installing these components. Is fixed to the frame 118.

In general, in such an optical scanning device, it is necessary to adjust the angle of a reflection mirror for guiding a light beam to a desired position on a scanned object, and a reflection mirror support mechanism is provided for this purpose.

[0005] The reflection mirror support mechanism 12 shown in FIG.
In the example of No. 0, the reflection surface side and one side end (front side in the figure) of the reflection mirror 112 are supported by the first support body 122 and the adjustment screw 124 provided in the housing 114, and the other side end (the back side in the figure). Side) is supported by a second support member 126, and the reflection mirror 11 is pressed by pressing the back surface of the mirror with an elastic member 128.
2 is fixed at a predetermined position on the optical path.

In order to guide the light beam to a desired position on the object to be scanned, the angle of the reflecting mirror 112 is changed by moving the adjusting screw 124 forward and backward. Such a reflecting mirror support mechanism is disclosed in, for example, Japanese Utility Model Laid-Open No. 1-1821.
No. 0 publication.

[0007] The optical scanning apparatus 100 having the above-described structure is similar to the optical scanning apparatus shown in FIG.
The frame 118 of the electrophotographic apparatus 130 as shown in FIG.
As described above, the object to be scanned 1 is incorporated in the upper part and rotates.
A light beam 102 containing information is scanned (main scanning direction) on 10. The surface of the object to be scanned 110 is uniformly charged by the charging means 132, and is exposed to light by being scanned with the light beam 102 to form an electrostatic latent image.

The electrostatic latent image is converted into a toner image by the developing means 134, and synchronized with these operations, the sheet conveying means 13
6 is transferred to the recording paper 138 conveyed by the recording paper 6. After the transfer, a fixing process is performed by the fixing unit 140, and the printed recording paper 138 is carried out to a tray (not shown).

As described above, in the electrophotographic apparatus 130, a number of vibration sources such as the sheet conveying means 136, a driving motor (not shown) for driving the scanning object 110, and the polygon motor 106 are provided inside the apparatus. Exists.
For this reason, those vibrations propagate through the frame 118 and the housing 114 to cause flexural vibration (resonance) in the reflection mirror 112 (the state shown by a two-dot chain line in the figure), and the scanning target 11
The light beam 102 guided to 0 deviates from the normal optical path (the state of the scanning line deviation indicated by 102A and 102B in the figure).
There was a problem of poor image quality.

As means for solving this problem, Japanese Patent Laid-Open No.
In the example of JP-A-253274, as shown in FIG. 28, a cushioning member 14 such as rubber or foamed polyurethane is provided between the bottom surface of the reflection mirror 112 and the bottom plate of the housing 114.
A method has been proposed in which the bending mirror 2 is interposed to suppress the bending vibration of the reflection mirror 112 (hereinafter referred to as Conventional Example 1).

As another example, Japanese Patent Application Laid-Open No. Hei 9-12003
In the publication No. 9, as shown in FIG.
The resonance frequency is changed by attaching a weight 144 to the back side of the device 12. In this example, the resonance frequency is separated from the input frequency of a polygon motor or the like by 20 Hz or more to achieve high image quality (hereinafter, Conventional Example 2). ).

[0012]

However, when the above-mentioned prior art 1 is incorporated in the above-described reflection mirror support mechanism (see FIG. 26), the angle adjustment is made because the cushioning member is made of rubber or the like which is soft and has high deformation resistance. The followability of the reflecting mirror in (advancing and retracting of the adjusting screw 124) is deteriorated. Particularly in the case of high precision adjustment, the operation is hindered. Further, in the reflection mirror support mechanism 150 having the configuration shown in FIG. 30, the reflection mirror 112 is hooked on the buffer member 142, and
(C) First support body 122 that supports the reflection surface as shown in FIG.
A gap Y is generated between them, and the light beam cannot be guided properly. Further, since the pressing force of the cushioning member may be weakened due to deterioration due to the change with time, there is a disadvantage that the vibration suppressing effect is reduced.

In recent years, there are many forms in which a plurality of resolutions and a plurality of printing speeds are provided by one optical scanning device. In this case, a buffer member is not necessarily required for all resolutions. Therefore, in the optical scanning device having the specific resolution, it takes time to remove the buffer member, and the manufacturing cost and the parts cost are wasted. Further, in the manufacturing process, it is necessary to control the presence or absence of a buffer member, and there is a possibility that a defect such as a missing item or the like may be caused in a device having a resolution to which a buffer member should be attached, which increases the cost of manufacturing and quality control. There is.

On the other hand, in the configuration of the second conventional example, since the reflection surface is distorted by attaching a weight to the back surface of the reflection mirror, there is a problem that the reflection accuracy of the light beam is deteriorated. Also here, the cost is expected to increase due to the addition of the parts cost and the mounting work.

In consideration of the above facts, the present invention is provided with an angle adjusting mechanism for the reflecting mirror, and can reliably and inexpensively suppress the flexural vibration of the reflecting mirror even in a configuration corresponding to a plurality of resolutions and printing speeds. It is an object to provide an optical scanning device that realizes high image quality by using the optical scanning device.

[0016]

According to a first aspect of the present invention, there is provided a light source, a rotating polygon mirror, an image forming lens system, a reflecting mirror for guiding a scanning line onto an object to be scanned, and a rotatably supporting the reflecting mirror. An optical scanning device having a mirror support portion for adjusting the angle of the reflection surface of the reflection mirror, and a housing for housing the mirror support portion, wherein the mirror support portion is movable in the longitudinal direction of the reflection mirror. It is characterized by that.

According to the first aspect of the present invention, the reflecting mirror is rotatably supported by the mirror supporting portion, and the angle of the reflecting surface is adjusted by the angle adjusting means to set the scanning line at a desired position on the object to be scanned. Lead. The mirror support is movable in the longitudinal direction of the reflection mirror.

Thus, the supporting length of the reflecting mirror, that is, the supporting point can be changed, and the natural frequency of the reflecting mirror can be changed. Therefore, even if the optical scanning device is adapted to a plurality of resolutions and printing speeds, bending vibration can be avoided by changing the resonance frequency at which the reflection mirror resonates with a vibration source such as a rotary polygon mirror.

In addition, the use of the mirror supporting portion for suppressing the flexural vibration eliminates the need to separately provide a vibration suppressing member as in the related art, and has a general versatility capable of coping with a plurality of resolutions only by moving the supporting point. As a result, costs can be reduced. Further, no extra stress is applied to the reflection mirror, and there is no adverse effect such as distortion of the reflection surface.

Further, the mirror supporting portion is made of a material having high rigidity equivalent to that of the housing, for example, so that the mirror supporting portion is also resistant to aging, so that the occurrence of resonance can be reliably prevented.

The mirror support according to the first aspect of the present invention is the first support and the second support for supporting both longitudinal sides on the reflection surface side or the back side of the reflection mirror. And at least three support portions as third support portions for supporting the bottom surface of the reflection mirror, and
A supporting portion is provided by a substrate selectively fixed to a plurality of fixing portions of a housing provided along the longitudinal direction of the reflecting mirror, and a first projecting member projecting from the substrate and supporting a bottom surface of the reflecting mirror. A plurality of the first protruding members may be provided on one substrate, and each member may have a different height.

Further, according to the invention described in any one of claims 1 to 3, as in claim 4, the mirror supporting portion is
In addition to the first support portion and the second support portion, a plurality of second protrusion members projecting from the housing and supporting the bottom surface of the reflection mirror may be provided, and the second protrusion member may be cut off from the housing. As in claim 5, the second of claim 4
The protruding member may be a first screw member that is screwed to a plurality of threaded portions of the housing provided along the longitudinal direction of the reflection mirror and supports the bottom surface of the reflection mirror.

The first projecting member, the second projecting member, and the first projecting member according to any one of the second to fifth aspects of the present invention.
As for the screw member, the head contacting the bottom surface of the reflection mirror may have an R surface such as a substantially spherical shape or a substantially cylindrical shape.

Further, in the invention according to any one of the first to sixth aspects, the angle adjusting means may be movable in the longitudinal direction of the reflection mirror as in the seventh aspect.

Further, the angle adjusting means is disposed on the same side as the first supporting portion and the second supporting portion, and supports the reflecting surface side or the back side of the reflecting mirror. An adjusting member for rotating the reflecting mirror about a line connecting the first mirror and the second supporting portion to the rotating shaft; and an urging means for urging the reflecting mirror toward the first supporting portion, the second supporting portion, and the adjusting member. , And the adjusting member may be selectively fixed to a plurality of second fixing portions of the housing provided along the longitudinal direction of the reflection mirror so as to be movable in the reflection mirror longitudinal direction.

The adjusting member may be constituted by a plate fixed to the second fixing portion and a projecting piece projecting from the plate and pressing the reflecting mirror. According to a tenth aspect, the plate member may be rotatable around a fixing member for fixing the plate member to the second fixing portion.

Further, in the invention according to any one of the first to tenth aspects, as in the eleventh aspect, the adjusting member includes
A second screw member for pressing the reflection mirror may be provided.

[0028]

Embodiments of the present invention will be described below with reference to the drawings.

[First Embodiment] As shown in FIG. 1, an optical scanning device 10 according to a first embodiment has a
The housing 14 is mounted on a main frame 12 in the electrophotographic apparatus, and the housing 14 is fixed by screws 16. A light source device 18 is provided in the housing 14. In the light source device 18, a light beam including information generated from a semiconductor laser is collimated by a collimator lens and emitted.

The light beam emitted from the light source device 18 is
Polygon motor 20 with cylindrical calns (not shown)
And is incident on the polygon motor 20. The incident light beam is deflected and scanned by the polygon motor 20, and is condensed as a light spot on the scanned object 24 by the imaging lens system 22. Here, the light beam including the information passing through the imaging lens system 22 is reflected by the reflection mirror 26.
And passes through the transmission port 28 of the housing 14,
An electrostatic latent image is formed on the surface of the scanning target 24.

Next, the support mechanism of the reflection mirror 26 will be described in detail.

In the first embodiment shown in FIGS. 2 to 4, the bottom plate 14A of the housing 14 is
The lower support plate 30 supporting the 6C is a screw 32
It is fixed at. The length of the lower support plate 30 is about half the longitudinal dimension of the reflection mirror, and is disposed near one end of the reflection mirror 26 in a direction parallel to the mirror.

Plate body 34 of lower support plate 30
A protrusion 36 and a protrusion 38 lower than the protrusion 36 protrude from the vicinity of both ends. Here, the protrusion 36 located at the center of the reflection mirror 26 is provided with a bottom surface 26C of the reflection mirror 26. Is supported at one point while tilted.

Further, at the other end of the reflection mirror 26,
A projection 40 lower than the projection 36 is also provided from the bottom plate 14A of the housing 14. These protrusions 36, 38, 40
Has a spherical head.

From the housing 14, a first support portion 42 is protruded in the vicinity of the protrusion 38, and a second support portion 44 is protruded in the vicinity of the protrusion 40, and supports the reflection surface 26A side of the reflection mirror 26 at two points. The reflection mirror 26 is provided on the first support portion 4.
It is configured to rotate about a line connecting the second support portion 44 and the second support portion 44 as an axis.

On the other hand, an L-shaped adjustment bracket 46 is fixed to the second support portion 44 with a screw 33.
An adjusting screw 4 is provided on the upper part of the adjusting bracket 46.
8 is screwed in, and the distal end is positioned above the reflecting surface 26A of the reflecting mirror 26 at a distance H from the supporting point of the second supporting portion 44.
(See FIG. 3 (C)).

Thus, the reflecting surface 2 of the reflecting mirror 26
The 6A side is supported by three points of a first support part 42, a second support part 44, and an adjustment screw 48.
The length H of the arm that generates the moment for rotating the arm 6 is secured.

Further, a spring 50 is fixed by a screw 33 on the back surface 26 B side of the reflection mirror 26. The bent portion 50A of the spring 50 is
6 and abuts against the back surface 26B, biases the reflection mirror 26 toward the first support portion 42, the second support portion 44, and the adjusting screw 48, and pushes the reflection mirror 26 as shown in FIG.
It is held almost horizontally as shown in FIG.

In the present embodiment, the dimensions of each part are set as follows.

The reflection mirror 26 has a length of L = 250 m.
m, width: W = 16 mm, and thickness: t = 5 mm.

The supporting point (center) of each supporting portion is shown in FIG.
(A)), the support point P1 of the first support part 42 is X1 = 10 mm from one end of the reflection mirror 26, and Y1 from the upper surface.
1 = 8 mm, the support point P2 of the second support portion 44 is X2 = 10 mm from the other end of the reflection mirror 26, and X2 is
= 14 mm. Adjustment screw 48
Of the reflection mirror 26 is located at X
3 = 10 mm, Y3 = 2 mm from the top.

On the other hand, in each of the supporting portions disposed below the reflecting mirror 26, first, the projection 40 is set such that X4 = 10 mm from the other end of the reflecting mirror 26 (X2 of the second supporting portion 44 and X3 of the adjusting screw 48). The same) and the lower support plate 3
0 is X4 = 10 mm (same as X1 of the first support portion 42) from one side end of the reflection mirror 26, and X5 = 125mm (10mm + 115m)
m).

In this embodiment, the lower support plate 30
Are the housing 14, the first support 42 and the second support 4
Material equivalent to 4, for example, engineering plastic material with glass filler (polycarbonate)
And metal (aluminum).

Next, the operation of the present embodiment will be described.

First, when guiding the light beam to a desired position on the object to be scanned, the adjusting screw 48 is moved forward and backward as in the prior art. Then, the reflection mirror 26 urged by the spring 50 rotates about the line connecting the first support part 42 and the second support part 44 as an axis. Thereby, the inclination of the reflection surface 26A is changed, and the scanning line can be adjusted to a desired position of the scanned object.

Here, the projection 36 of the lower support plate 30 supporting the lower portion of the reflection mirror 26 has a spherical head. Thereby, the bottom surface 26C of the reflection mirror 26 is formed.
, And the reflecting mirror 26 turns following the spherical surface thereof, so that the turning operation is smooth. Further, in the contact portion, the frictional resistance against the urging force of the spring 50 is sufficiently small.
2 and the second support portion 44 do not separate.

Further, even if the attitude of the reflecting mirror 26 is slightly inclined as indicated by the g line in FIG. 4A by the angle adjustment, the reflecting mirror 26 is securely in contact with the projection 36 due to its own weight. One point support is maintained by the clearance (CL in the figure) between the portion 38 and the protrusion 40.

In this embodiment, such a support state of the reflection mirror 26 is applied to the resolution A shown in FIG.

In the B resolution, the screw 32 fixing the lower support plate 30 is removed, and as shown in FIG. 4 (B), the projections 36 and 38 are inverted and mounted so that the positions thereof are interchanged. The support state of the reflection mirror 26 is changed. Here, a clearance is formed between the projection 38 disposed at the center of the reflection mirror 26 and the bottom surface 26C, and the reflection mirror 26 is supported by the projections 36 and the projections 40 located on both sides.

Therefore, the supporting point of the reflecting mirror 26 changes from one point at the center to two points on both sides, and the reflecting mirror 2
The natural frequency of No. 6 changes. Therefore, as can be seen from FIG. 4, the resonance frequency with the vibration source is greatly changed, and the bending vibration at the B resolution can be suppressed.

As described above, the optical scanning device 10 according to the present embodiment has two resolutions A and B,
Even when the printing speed is supported, the resonance frequency of the reflection mirror 26 can be changed by moving the protrusion 36 supporting the bottom surface 26C of the reflection mirror 26 to change the supporting point. Can be avoided.

Further, the reflection mirror 26 is used to suppress bending vibration.
By using the supporting portion, there is no need to separately provide a vibration suppressing member or the like, and in addition, since there is versatility that can easily cope with a plurality of resolutions, the cost can be suppressed. Further, since no stress is applied to the reflection mirror 26, the reflection surface 26A is not distorted.

As described above, since the lower support plate 30 is made of the same material (polycarbonate containing glass fiber, etc.) as the housing 14, it is resistant to environmental influences such as temperature and humidity and changes over time. The deformation is small, and the reflection mirror 26 can be stably supported to reliably prevent the occurrence of resonance.

[Second Embodiment] Next, a second embodiment of the present invention will be described. In this second embodiment,
Since the configuration is almost the same as that described in the first embodiment, the same components are denoted by the same reference numerals and description thereof is omitted.

In the second embodiment shown in FIGS. 5 to 7, the projections 36 (first embodiment) provided on the plate body 34 of the lower support plate 30 are replaced with projections 52 as shown. Is protruding. The projection 52 is provided on the reflection mirror 2.
6 is formed in a substantially semi-cylindrical shape having an R surface at the contact portion with the bottom surface 26 </ b> C, and formed in a direction parallel to the longitudinal direction of the reflection mirror 26. Here, the length: S = 10 mm, the center of the support portion (the contact portion with the bottom surface 26C) is located at the same position as the protrusion 36 of the first embodiment, and the height is also the same.
(Δh in FIG. 6C).

On the other hand, an arm portion 54 extends from the upper portion of the spring 50 which urges the back surface 26B of the reflection mirror 26, and the R portion 54A at the tip end causes the reflection portion 26A.
Is pressed.

Thus, when assembling the reflection mirror 26 in the housing 14, the reflection mirror 26 is placed on the projection 52, so that the balance between left and right is stabilized, and workability is improved.

Also, in this case, the abutting portion with the mirror bottom surface 26C is in the form of an R surface, so that it is in line contact with the mirror mirror 26. It is.

Further, the mirror upper surface 26D is
By pressing with the zero arm portion 54, the mirror bottom surface 26C can be reliably prevented from separating from the protrusion 52 even when a strong impact or the like is received. Further, since the R portion 54A is also in line contact with the upper surface 26D of the reflecting mirror 26, the frictional resistance is small, and the turning operation of the reflecting mirror 26 during the angle adjustment is not hindered.

In this embodiment, the reflection mirror 26 is used.
Since the support state of the bottom surface 26C is different from that of the first embodiment, the resonance frequency also differs. Therefore, the present invention is applied to an optical scanning device having C and D resolutions as shown in FIG.

The length S of the projection 52 can be changed as appropriate in accordance with the size of the reflection mirror, the target resolution, and the like. Further, the arm portion 54 provided integrally with the spring 50 may be provided separately.

The reflection mirror 2 according to the present embodiment
The configuration in which the upper surface 26D of the sixth part is pressed can also be applied to the first embodiment.

[Third Embodiment] Next, a third embodiment of the present invention will be described. Since the third embodiment has almost the same configuration as that described in the first embodiment, the same components are denoted by the same reference numerals and description thereof is omitted.

In the third embodiment shown in FIGS.
The plate body 58 of the lower support plate 56 is shorter than in the first embodiment, and the projection 6 for supporting the bottom surface 26C of the reflection mirror 26 at the center of the plate body 58.
0 is protruding.

The height of the protrusion 60 is also the same as the height of the protrusion 36 in the first embodiment, and the protrusion 40 protruded from the bottom plate 14A of the housing 14 and the first support portion. The height is higher than that of the protrusion 41 disposed in the vicinity of 42.

The bottom plate 14A of the housing 14 has
A plurality of tap holes 62 for fixing the lower support plate 56 are formed along the longitudinal direction of the reflection mirror 26, and the lower support plate 56 adjusts the length of the reflection mirror 26 in accordance with the position of the tap hole 62. It can be moved stepwise in the direction. Further, here, the protrusion 60 is the first
In addition to the positions corresponding to the protruding portions 36 and 38 in the embodiment of the present invention, it is possible to arrange them almost at the middle thereof.

As a result, the number of choices of the support points for supporting the reflection mirror 26 increases, and A and B in the first embodiment are changed.
In addition to the resolution (see FIGS. 10A and 10B), FIG.
As shown in (C), it is possible to change the resonance frequency corresponding to the E resolution.

Here, by changing the size of the lower support plate 56, the number of tap holes 62, and the interval,
It is possible to adapt to four or more resolutions.

The lower support plate 5 of the present embodiment
6, when the protrusions 60 are arranged corresponding to the B resolution, as shown in FIG. 9A, a gap 61 for containing the protrusions 41 is formed.

In the modification shown in FIG. 9B, the mounting hole of the lower support plate 56 is a long hole 63, which allows fine adjustment of the resonance frequency at each resolution.

Also in this embodiment, as a countermeasure against displacement of the reflection mirror due to impact or the like, the configuration of pressing the upper surface of the reflection mirror described in the second embodiment can be applied.

[Fourth Embodiment] Next, a fourth embodiment of the present invention will be described. Since the fourth embodiment has almost the same configuration as that described in the first embodiment, the same components are denoted by the same reference numerals and description thereof is omitted.

In the fourth embodiment, as shown in FIGS. 11 and 12, three projections 6 for supporting the bottom surface 26C of the reflection mirror 26 from the bottom plate 14A of the housing 14.
4, 66 and 68 are protruded.

The relationship between the heights of the protrusions is as follows.
6 (h1) is the highest, and then the protrusion 64 (h2) arranged at a predetermined interval on the left side and the protrusion 68 (h) arranged on the right side.
The order is 3), and the heights of the lowest protrusions 40 (h2) and 41 (h5) at both ends are equal.

Further, peripheral grooves 70 are formed around the bases of the protrusions 64, 66, 68, respectively, whereby the protrusions 64, 66, 68 can be cut from near the bases. .

Therefore, as shown in FIG. 12, the positions of the protrusions 64, 66, and 68 are determined and provided so as to have a desired resonance frequency, and the protrusions corresponding to the target resolution are left when the optical scanning device 10 is manufactured. If cut off, the resonance frequency of the reflection mirror 26 can be set to an appropriate value from among a plurality of values,
Here, in addition to the above-described A, B, and E resolutions, the bending vibration at the F resolution can be avoided.

As described above, even with a simple configuration in which a plurality of protrusions are provided on the housing 14, a plurality of resonance frequencies of the reflection mirror 26 can be selected, and cost reduction can be realized.

Also in this embodiment, the structure for pressing the upper surface of the reflecting mirror described in the second embodiment can be applied.

[Fifth Embodiment] Next, a fifth embodiment of the present invention will be described. Since the fifth embodiment also has substantially the same configuration as that described in the first embodiment, the same components are denoted by the same reference numerals and description thereof is omitted.

In the fifth embodiment, a mirror support screw for supporting the lower part of the reflection mirror is provided instead of the plurality of projections described in the fourth embodiment.

Here, as shown in FIGS. 13 and 14, a tap hole 72 is formed in the bottom plate 14A of the housing 14 at the same position as the projections 64, 66, 68 of the fourth embodiment. A mirror support screw 74 is screwed into the tapped hole 72. Then, the mirror support screw 74 is extended in accordance with each resolution, and the reflection mirror 2 is set.
The resonance frequency of the reflection mirror 26 is changed by contacting and supporting the bottom surface 26C of the reflection mirror 26.

As described above, even when the mirror support screw 74 is provided in the housing 14, the bending vibration of the reflection mirror 26 can be suppressed.

The use of such a screw member (mirror support screw 74) facilitates attachment and detachment to the housing 14, that is, the resonance frequency can be easily increased and reduced simply by changing the arrangement of the mirror support screw 74. It is possible to change the model at the time of manufacture,
It can flexibly respond to OT adjustment and the like.

Further, if the mirror support screw 74 is made of metal and a screwing agent or the like is appropriately used in combination, for example,
Problems such as aging can be reliably prevented.

Also in this embodiment, the structure for pressing the upper surface of the reflecting mirror described in the second embodiment can be applied.

[Sixth Embodiment] Next, a sixth embodiment of the present invention will be described. Since the sixth embodiment has substantially the same configuration as that described in the first embodiment, the same components are denoted by the same reference numerals and description thereof is omitted.

The feature of the present embodiment is that the support portion for supporting the reflecting mirror is not moved as in the first to fifth embodiments, but the angle adjustment portion is moved.

In the sixth embodiment shown in FIGS. 15 to 18, a projection 80 extends from the bracket body 78 of the adjustment bracket 76 so that the projection 80 supports the reflection surface 26A of the reflection mirror 26. Has become.

The bottom plate 14A of the housing 14 is provided with a concave portion 82 for positioning the adjustment bracket 76. The concave portion 82 has a tapped hole 84 for fixing the adjustment bracket 76 with the screw 33. Three are provided along the longitudinal direction of the mirror 26. As a result, the mounting position of the adjustment bracket 76 is changed, and a plurality of resonance frequencies of the reflection mirror 26 can be selected.

Further, as shown in FIG.
The abutting portion V of the concave portion 82 that determines the attitude of the mirror body is set so that the dimension K with the second support portion 44 is set with high accuracy, and the position of the reflecting mirror 26 from the end surface of the bracket body 78 (the inclination angle of the reflecting surface 26A) The distance J to the protruding piece 80 and the height I of the projection 80 are also set with high accuracy so that the scanning line leading to the object to be scanned is at an appropriate position.

In this embodiment, the reflection mirror 26 is used.
The pitch of the tapped holes 84 is set to 14 mm, and the total is set to 28 mm.
If the movable range of 6 is at this level, it is possible to sufficiently house it in the housing.

Here, from the G pattern shown in FIG. 17A to the H pattern shown in FIG.
The amount of movement from the pattern to the I pattern shown in (C) is 1
Each of the following frequencies can be shifted by 20 Hz or more. That is, it is a value sufficient to avoid the resonance described in Conventional Example 2 (Japanese Patent Application Laid-Open No. 9-120039).

Further, the adjustment bracket 76 has a left-right symmetric structure, and the distance J from the end face of the bracket body 78 to the tip of each of the projecting pieces 80 on both sides and the height I thereof are the same (FIG. 16). Therefore, as shown in FIG. 18, the bracket body 78 is turned from the direction of (A) with the tapped hole 84 and the screw 33 as the rotation center (B).
And the support point of the reflection surface 26A can be moved. Further, by combining with three mounting positions, a total of six types of support points, that is, the resonance frequency of the reflection mirror 26 can be selected.

As shown in FIG. 19, if the mounting hole of the adjustment bracket 76 can be slid as the elongated hole 86, the resonance frequency can be finely adjusted, and more detailed settings can be handled.

With these configurations, the adjusting screw can be omitted in many optical scanning devices, and the adjusting cost can be reduced. In addition, the resonance frequency of the reflection mirror can be stably changed in several steps without being affected by environmental changes or disturbances and without affecting the reflection surface.

Further, even when the precision error of each component is large and the scanning line cannot be guided to the object to be scanned within the tolerance, the tapping hole for the adjusting screw can be left as shown in FIG. The orientation of the reflecting mirror 2 is temporarily changed by 90 degrees using the adjusting screw 48.
6 can be adjusted.

In this embodiment, the effect of preventing the reflection mirror 26 from shifting due to an impact or the like can be similarly obtained by providing the pressing portion from above the mirror described in the second embodiment.

[Seventh Embodiment] Next, a seventh embodiment of the present invention will be described. The seventh embodiment is a modified example of the above-described sixth embodiment, and has substantially the same configuration. Therefore, the same components are denoted by the same reference numerals and description thereof will be omitted.

In the seventh embodiment shown in FIGS. 21 to 24, the mounting portion 90 of the adjustment bracket 88 has a disk shape. The mounting portion 90 is attached to the bottom plate 14A of the housing 14.
As shown in FIG. 23, the screw 3
3 (and the tap hole 84) can be rotated.

Therefore, the projecting piece 8 of the adjustment bracket 88
0 can be moved from the nominal position to R1 and R2, and after adjusting the angle of the reflection mirror 26, the screw 32 can be fastened and fixed at a desired position.

As a result, even if the adjusting screw is omitted, the angle of the reflecting mirror 26 can be adjusted, and the cost can be reduced while securing a wide adjusting range.

Further, the adjustment bracket 88 of the present embodiment
Are also made symmetrically as shown in FIG.
As shown in FIG. 24, the direction can be reversed from the direction of (A) as in (B), and it is possible to cope with many resonance frequency patterns as in the sixth embodiment.

In addition to the first to seventh embodiments described above, various changes can be made within the scope of the claims. For example, in order to change the resonance frequency of the reflection mirror, the projections supporting the mirror bottom surface and the angle adjustment unit supporting the reflection surface are moved, but the first support unit 42 and the second support unit 44 are moved. Or they can be combined. Further, the support point may be a rear surface or a top surface in addition to the reflection surface and the bottom surface of the reflection mirror.

[0104]

As described above, the optical scanning device of the present invention has the above-described configuration, and thus has an angle adjusting mechanism for the reflection mirror and a configuration corresponding to a plurality of resolutions and printing speeds.
Flexural vibration of the reflecting mirror can be reliably and inexpensively suppressed, and high image quality can be realized.

[Brief description of the drawings]

FIG. 1 is a schematic configuration diagram showing a state where an optical scanning device of the present invention is mounted on an electrophotographic apparatus.

FIG. 2 is a perspective view of a reflection mirror support mechanism of the optical scanning device according to the first embodiment of the present invention.

FIG. 3 shows a side sectional view of FIG.
2 is a sectional view taken along line A, FIG. 2B is a sectional view taken along line BB of FIG. 2, and FIG. 2C is a sectional view taken along line CC of FIG.

FIG. 4 is an explanatory diagram for changing the resonance frequency of the reflection mirror according to the first embodiment of the present invention.

FIG. 5 is a perspective view of a reflection mirror support mechanism of an optical scanning device according to a second embodiment of the present invention.

6A and 6B show the lower support plate of FIG. 5, wherein FIG. 6A is a plan view and FIG. 6B is a front view.

FIG. 7 is an explanatory diagram for changing a resonance frequency of a reflection mirror according to a second embodiment of the present invention.

FIG. 8 is a perspective view of a reflection mirror support mechanism of an optical scanning device according to a third embodiment of the present invention.

9A and 9B show the lower support plate of FIG. 8, wherein FIG. 9A is an enlarged perspective view and FIG. 9B is an enlarged perspective view of a modification.

FIG. 10 is an explanatory diagram for changing a resonance frequency of a reflection mirror according to a third embodiment of the present invention.

FIG. 11 is a perspective view of a reflection mirror support mechanism of an optical scanning device according to a fourth embodiment of the present invention.

FIG. 12 is an explanatory diagram for changing a resonance frequency of a reflection mirror according to a fourth embodiment of the present invention.

FIG. 13 is a perspective view of a reflection mirror support mechanism of an optical scanning device according to a fifth embodiment of the present invention.

FIG. 14 is an explanatory diagram for changing a resonance frequency of a reflection mirror according to a fifth embodiment of the present invention.

FIG. 15 is a perspective view of a reflection mirror support mechanism of an optical scanning device according to a sixth embodiment of the present invention.

16 is a detailed view of the reflection mirror adjusting mechanism of FIG.

FIG. 17 is an explanatory diagram for changing the resonance frequency of the reflection mirror according to the sixth embodiment of the present invention.

FIG. 18 is an explanatory diagram for changing a mounting direction of the adjustment bracket of FIG. 15;

FIG. 19 is an enlarged perspective view showing a modification of the adjustment bracket of FIG.

FIG. 20 is a perspective view showing another modified example of the adjustment bracket of FIG.

FIG. 21 is a perspective view of a reflection mirror support mechanism of an optical scanning device according to a seventh embodiment of the present invention.

22 (A) is a plan view, FIG. 22 (B) is a front view, and FIG. 22 (C) is a side view.

FIG. 23 is an explanatory view showing an adjustment position of the adjustment bracket of FIG. 21;

FIG. 24 is an explanatory diagram for changing a mounting direction of the adjustment bracket of FIG. 21;

FIG. 25 is a perspective view illustrating a configuration of a conventional optical scanning device.

FIG. 26 is a side sectional view of the conventional general reflection mirror adjusting mechanism in FIG. 25;

FIG. 27 is an explanatory diagram for describing a problem of a conventional optical scanning device.

FIG. 28 is a perspective view for explaining the configuration of another conventional optical scanning device.

FIG. 29 shows still another conventional optical scanning device;
(A) is a schematic configuration diagram of an optical scanning device, and (B) is a perspective view of a reflection mirror.

FIG. 30 is a diagram illustrating a problem when the reflection mirror support mechanism of FIG. 28 is incorporated in the optical scanning device according to the present embodiment.

[Explanation of symbols]

Reference Signs List 10 optical scanning device 14 housing 18 light source device (light source) 20 polygon motor (rotating polygon mirror) 22 imaging lens system 24 scanned object 26 reflection mirror 26A reflection surface 26B back surface 26C bottom surface 30, 56 lower support plate (mirror support / Third
Supporting part) 33 Screw (fixing member) 34, 58 Plate body (substrate) 36, 38, 52, 60 Projecting part (first projecting member) 42 First supporting part (mirror supporting part) 44 Second supporting part (mirror supporting) Part) 46, 76, 88 adjustment bracket (angle adjustment means /
Adjusting member) 48 Adjusting screw (second screw member) 50 Spring (angle adjusting means / biasing means) 62 Tap hole (first fixing portion) 64, 66, 68 Projecting portion (second projecting member) 72 Tap hole (screw) Part) 74 Mirror support screw (first screw member) 78 Bracket body (plate material) 80 Protrusion piece 84 Tapped hole (second fixing part)

Claims (11)

[Claims] 1. A light source, a rotating polygon mirror, an image forming lens system, a reflecting mirror for guiding a scanning line onto an object to be scanned, a mirror supporting portion for rotatably supporting the reflecting mirror, and an angle of a reflecting surface of the reflecting mirror. An optical scanning device comprising an angle adjusting means for adjusting the angle, and a housing accommodating them, wherein the mirror support is movable in a longitudinal direction of the reflection mirror. 2. A first support portion and a second support portion for supporting at least both sides in a longitudinal direction of a reflection surface side or a back surface side of the reflection mirror, and a mirror support portion for supporting a bottom surface of the reflection mirror. And a substrate that is selectively fixed to a first fixing portion of the housing, the plurality of third supporting portions being provided along a longitudinal direction of the reflection mirror; and The optical scanning device according to claim 1, further comprising: a first protruding member that protrudes and supports a bottom surface of the reflection mirror. 3. The optical scanning device according to claim 2, wherein a plurality of the first protrusions are provided on one substrate, and the first protrusions have different heights. 4. At least the mirror support portion includes the first support portion and the second support portion, and a plurality of second protrusion members protruding from the housing and supporting a bottom surface of the reflection mirror. The optical scanning device according to any one of claims 1 to 3, wherein the second protruding member is capable of being cut from the housing. 5. The reflection device, wherein at least the mirror support portion is screwed to the first support portion, the second support portion, and a plurality of screw portions of the housing provided along a longitudinal direction of the reflection mirror. The optical scanning device according to claim 1, further comprising a first screw member that supports a bottom surface of the mirror. 6. The head of the first protruding member, the second protruding member, and the first screw member, which comes into contact with a bottom surface of the reflection mirror, has an R surface. The optical scanning device according to claim 5. 7. The optical scanning device according to claim 1, wherein said angle adjusting means is movable in a longitudinal direction of said reflection mirror. 8. The angle adjusting means is disposed on the same side as the first support and the second support to support the reflection surface side or the back side of the reflection mirror, and the first support portion and the second support portion are connected to each other. An adjusting member for rotating the reflecting mirror about a line connecting the supporting portion to the rotating shaft; and an adjusting member for connecting the reflecting mirror to the first supporting portion and the second
A biasing unit configured to bias the support member and the adjustment member, wherein the adjustment member is selected from a plurality of second fixing portions of the housing provided along the longitudinal direction of the reflection mirror. The optical scanning device according to any one of claims 1 to 7, wherein the optical scanning device is fixed in a fixed manner and is movable in a longitudinal direction of the reflection mirror. 9. The apparatus according to claim 1, wherein the adjusting member includes a plate fixed to the second fixing portion, and a projection extending from the plate and pressing the reflection mirror. An optical scanning device according to claim 8. 10. The apparatus according to claim 1, wherein the plate is rotatable around a fixing member for fixing the plate to the second fixing portion. Optical scanning device. 11. The optical scanning device according to claim 1, wherein the adjustment member is provided with a second screw member that supports the reflection mirror and adjusts an angle. apparatus.