JP2012108329A - Light source holder, laser scanning optical device, and image forming apparatus - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a light source holder, a laser scanning optical device, and an image forming apparatus that suppress displacement of an attachment bearing surface in swaging a light source to be fixed to a light source holder.SOLUTION: A light source holder 20 includes convex portions 23 to 25 arranged at positions where areas S1 to S3 each of which surrounds each of the convex portions 23 to 25 and the center C of an insertion hole 21, and areas T1 to T3 each of which surrounds each of protrusions 31 to 33 and the center C, are not overlapped.

Description

  The present invention relates to a light source holding holder, a laser scanning optical device, and an image forming apparatus.

  2. Description of the Related Art Conventionally, an image forming apparatus such as a laser printer or a copying machine is provided with a laser scanning optical device for scanning a photoconductor using a semiconductor laser emitted from a light source held by a light source holding holder. The laser scanning optical device uses a multi-beam method (when a semiconductor laser scans a photoconductor simultaneously using a plurality of light sources) in order to speed up or increase the density of image forming processing by the image forming apparatus. Methods such as increasing the number of beams or reducing the beam diameter for exposing the photosensitive member are taken.

  In performing such a method, positioning of the relative position (beam pitch) between the beams becomes important as the number of beams in the multi-beam method is increased, and the amount of change in the beam diameter is suppressed as the beam diameter is reduced. Is important. Therefore, in a laser scanning optical device, it is important how to fix a light source having a very high sensitivity to an error with respect to a relative position between beams and a beam diameter to a light source holding holder.

For example, as a method of fixing the light source, the light source is screwed to the light source holding holder in a state where the light source is inserted into the insertion hole formed in the light source holding holder, and the light source is pressed to the light source holding holder by a leaf spring. Are press-fitted into the light source holding holder, and the light source is laser welded to the light source holding holder.
However, in the screwing method, variation in tightening torque is unavoidable, and there is a possibility that the screw may be loosened due to vibration caused by an external force. Further, in the pressing method, since the spring constant of the leaf spring varies as the number of parts increases, the pressing force also varies, which may reduce the reliability. In addition, since the dimensional tolerance width of the outer peripheral portion of the light source is relatively large in the press-fitting method, it is necessary to make the reference size of the hole diameter of the insertion hole small, so that the resin material that is easily elastically deformed as the material of the light source holding holder, etc. May cause restrictions. Further, in the laser welding method, it can be expected that the light source is securely held in the light source holding holder, but there is a risk that it takes time to position the light source holding holder and the installation of welding equipment is costly.
Therefore, taking into account the above problems, a method of caulking and fixing the light source to the light source holding holder by pressing a rivet provided on the light source holding holder and plastically deforming it so as to cover the upper surface of the light source is considered. It is done.

  Therefore, for example, a polygon scanner driving device for fixing the polygon mirror to the flange member by attaching the polygon mirror to the mounting seat surface of the flange member and plastically deforming the protruding portion of the flange member by outward caulking using a caulking die Is known (see Patent Document 1). Here, the mounting seat surface of the flange member is provided at a position close to the protrusion in the vertical direction (substantially directly below the protrusion).

Japanese Patent Laid-Open No. 9-230268

  However, when the invention described in Patent Document 1 is used for the method of caulking and fixing the light source to the light source holding holder, considering that the light source that emits the semiconductor laser is a small element, the mounting seat in the position close to the protrusion The surface may be displaced due to the influence of stress generated when the projection of the light source holding holder is caulked and plastically deformed. That is, when the invention described in Patent Document 1 is used, the optical axis of the semiconductor laser emitted from the light source is deviated from an ideal position due to the displacement of the mounting seat surface. There was a problem of causing performance deterioration.

  SUMMARY OF THE INVENTION An object of the present invention is to provide a light source holding holder, a laser scanning optical device, and an image forming apparatus that suppress the displacement of the mounting seat surface when caulking and fixing the light source to the light source holding holder.

  In order to solve the above problems, the invention described in claim 1 is a light source holding holder for holding a light source, and includes a main body portion, an insertion hole for inserting the light source through the main body portion, and an upper surface. Protruding and projecting in the vicinity of the edge of the insertion hole on the upper surface of the main body portion and a seating surface portion for positioning in the optical axis direction of the light source inserted into the insertion hole. And a protrusion that is plastically deformed so as to cover the upper surface of the light source inserted into the insertion hole, and the convex portion has the convex portion and the center of the insertion hole in a top view of the main body portion. And a region surrounding the protrusion and the center of the insertion hole are arranged at positions where they do not overlap each other.

Invention of Claim 6 is a laser scanning optical apparatus, Comprising: The light source holding holder of any one of Claims 1-5 which hold | maintains the light source which can radiate | emit a semiconductor laser beam, and radiate | emits from the said light source A first optical system that collimates the semiconductor laser light to be converted, a second optical system that converts the semiconductor laser light collimated by the first optical system into convergent light in the sub-scanning direction, and A deflector for deflecting the semiconductor laser light converted into convergent light by the second optical system; and a third optical system for condensing the semiconductor laser light deflected by the deflector onto the photosensitive member. It is characterized by that.

  According to a seventh aspect of the present invention, there is provided an image forming apparatus including the laser scanning optical apparatus according to the sixth aspect.

  Therefore, the present invention can provide a light source holding holder, a laser scanning optical device, and an image forming apparatus that suppress the displacement of the mounting seat surface when the light source is caulked and fixed to the light source holding holder.

1 is a diagram illustrating a schematic configuration of an image forming apparatus according to a first embodiment of the present invention. It is a figure which shows schematic structure of the laser scanning optical apparatus with which the image forming apparatus shown in FIG. 1 is equipped. It is the figure which represented typically the structure of the light source holding holder and light source with which the laser scanning optical apparatus of FIG. 2 was equipped, and illustrated the state before caulking and fixing a light source to a light source holding holder. FIG. 4 is a diagram illustrating a state after the light source is caulked and fixed to the light source holding holder in the light source holding holder and the light source shown in FIG. 3. It is VV sectional drawing of FIG. It is the figure which illustrated the state before mounting | wearing with the light source of the light source holding holder shown in FIG. FIG. 4 is a top view of the light source holding holder and the light source shown in FIG. 3. It is VIII-VIII sectional drawing of FIG. It is the figure which illustrated the light source holding holder which concerns on Embodiment 2 of this invention. It is the figure which illustrated the modification 1 of the light source holding holder shown in FIG. It is the figure which illustrated the modification 2 of the light source holding holder shown in FIG.

  The image forming apparatus according to the first embodiment will be described below with reference to FIGS.

  The image forming apparatus 1000 according to the present embodiment is used as, for example, a copying machine or a printer, and as shown in FIG. 1, a plurality of lasers provided for each color of cyan, magenta, yellow, and black. The scanning optical device 1 includes a photosensitive member 200 such as a photosensitive drum provided according to the laser scanning optical device 1, an intermediate transfer belt 300, a transfer roller 400, a fixing unit 500, and the like. .

  The image forming apparatus 1000 forms a toner image on the photoconductor 200 that is exposed to the laser light emitted from the laser scanning optical apparatus 1 and transfers the toner image onto the intermediate transfer belt 300. Further, the image forming apparatus 1000 presses and transfers the toner image transferred to the intermediate transfer belt 300 onto the paper P by the transfer roller 400, and heats and presses the paper P by the fixing unit 6. Fix on the paper P. Then, the image forming apparatus 1000 performs the image forming process by conveying the paper P by a paper discharge roller (not shown) and discharging it to a tray (not shown).

  Here, as shown in FIG. 2, the laser scanning optical device 1 includes an optical housing 2 for exposing the photosensitive member 200 with the laser light L emitted toward the photosensitive member 200. The laser scanning optical device 1 uses a multi-beam method in which a plurality of laser beams L are simultaneously irradiated onto the photosensitive member 200 and a plurality of scanning lines are simultaneously scanned.

  The optical housing 2 includes a light source unit 10 that emits laser light L, a first optical system 100 that collimates the laser light L emitted from the light source unit 10, and the first optical system 100. The second optical system 110 that converges only the sub-scanning direction component of the laser light L, the deflector 120 that deflects the laser light L that has passed through the second optical system 110, and the laser light deflected by the deflector 120 A third optical system 130 for condensing L, a fourth optical system 140 for condensing a part of the laser light L deflected by the deflector 120, and a laser light L transmitted through the fourth optical system 140. And a sensor 150 for inputting.

The light source unit 10 includes a plurality of light sources 11 arranged linearly and a light source holding holder 20 that holds each light source 11.
The light source 11 is a semiconductor laser that emits laser light L.
The light source holding holder 20 is a holder for holding the light source 11 and caulking and fixing the mounted light source 11.
Here, a configuration in which the light source holding holder 20 caulks and fixes the light source 11 will be described later.

The first optical system 100 includes a collimator lens and the like, and collimates the laser light emitted from the light source unit 10.
The second optical system 110 includes a slit and a cylindrical lens. The second optical system 110 limits the transmission amount of the laser light L that has been collimated by the first optical system 100 so that the beam spot is shaped on the photoconductor 200 by the slit. In addition, the second optical system 110 converges only the sub-scanning direction component of the laser light L that has been collimated by the first optical system 100 using a cylindrical lens.

  The deflector 120 includes a polygon mirror having a polygonal column shape whose side surface is a mirror surface, and a motor that rotates the polygon mirror by applying rotational force to the polygon mirror. The deflector 120 deflects the laser light L transmitted through the second optical system 110 in a direction corresponding to the rotation. Then, the deflector 120 irradiates the peripheral surface of the photosensitive member 200 with the deflected laser light L via the third optical system 130. At this time, since the deflector 120 irradiates the laser beam L at a different position in the longitudinal direction of the photosensitive member 200 according to the rotational position, the laser beam L in the main scanning direction (longitudinal direction of the photosensitive member 200 in FIG. 2). Enables scanning.

  The third optical system 130 forms an image of the laser beam L deflected by the deflector 120 on the surface of the photoconductor 200.

The fourth optical system 140 includes a cylindrical lens. Then, the fourth optical system 140 condenses part of the laser light L deflected by the deflector 120 and causes the condensed laser light L to enter the sensor 150.
The sensor 150 is an optical sensor that detects the laser light L collected by the fourth optical system 140. Then, a control unit (not shown) of the image forming apparatus 1000 including the laser scanning optical device 1 adjusts the timing of the writing position on the photoconductor 200 based on the detection signal detected by the sensor 150.

(Configuration where the light source holder holds the light source)
Next, a configuration in which the light source holding holder 20 fixes the light source 11 will be described with reference to FIGS. In the following description, the axial direction of the light source holding holder 20 having a substantially cylindrical shape shown in FIG. Further, in the light source holding holder 20, the side on which the protrusions 31 to 33 (projections) are provided is the upper side, the direction opposite to the upper side is the lower side, the direction in which the light source holding holder 20 is expanded is the outer side, and the light source holding holder 20 is For the sake of convenience, the direction of diameter reduction is defined as the inside.

  As shown in FIGS. 3 and 4, the light source holding holder 20, with the light source 11 mounted, presses the three projecting portions 31 to 33 formed on the upper surface of the main body portion 28, and the jig presses the light source holding holder 20. The light source 11 is caulked and fixed by being caulked (plastically deformed) so as to cover the upper surface of 11.

  Here, the light source 11 includes, as shown in FIGS. 3 to 5, a main body portion 12 having a cylindrical shape, and a cylindrical flange portion 13 provided on the upper portion of the main body portion 12 and having a diameter larger than that of the main body portion 12. And a terminal 15 formed on the upper surface of the flange portion 13.

As shown in FIG. 6, the light source holding holder 20 includes a substantially cylindrical main body 28 through which an insertion hole 21 for inserting the light source 11 is inserted at the center of a column. The protrusions 31 to 33 are provided in the vicinity of the edge of the insertion hole 21 on the upper surface of the main body 28. The protrusions 31 to 33 have a cylindrical shape protruding upward. Then, as shown in FIG. 4, when the protrusions 31 to 33 are pressed downward by a caulking jig, the protrusions 31 to 33 are plastically deformed so as to contract in the vertical direction and expand in a plane direction perpendicular to the vertical direction, The light source 11 is fixed over the upper end of the flange portion 13.
Further, the insertion hole 21 is formed with an annular fitting groove 22 having a diameter slightly larger than that of the flange portion 13 and fitting the flange portion 13 therein. The lower end of the fitting groove 22 is provided with a seating surface portion 29 which is a mounting seating surface for positioning the light source 11 inserted (fitting the flange portion 13) in the Z-axis direction. The seat surface portion 29 is formed with three convex portions 23 to 25 that are convex upward. The position of the light source 11 in the Z-axis direction when attached to the light source holding holder 20 is determined.

Here, as shown in FIG. 7, in the top view of the main body portion 28, the regions surrounded by the convex portions 23 to 25 and the center C of the insertion hole 21 are inserted into S1 to S3 and the protruding portions 31 to 33. A region surrounded by the center C of the hole 21 is defined as T1 to T3. Then, as can be understood from FIG. 7, the convex portions 23 to 25 are disposed at positions where the regions S1 to S3 and the regions T1 to T3 do not overlap each other.
The convex portions 23 to 25 are arranged as described above because the convex portions 23 to 25 are not affected by the stress generated in the main body 28 when the projections 31 to 33 are pressed and plastically deformed. It is for doing so. That is, as shown in FIG. 8, when the protrusions 31 (˜33) are pressed and plastically deformed by the caulking jig, a stress P is generated inside the main body 28. At this time, since the region T1 (to T3) inside the main body 28 corresponds to a region in the vicinity of the position where the stress P is generated, when the convex portions 23 to 25 are disposed in the region T1 (to T3), The convex portions 23 to 25 are easily affected by the stress P. Therefore, by arranging the convex portions 23 to 25 in the regions S1 to S3 that are separated from the regions T1 to T3 that are easily affected by the stress P, the convex portions 23 to 25 are displaced due to the influence of the stress P. Can be prevented.

(Caulking fixed operation)
Next, the operation when caulking and fixing the light source 11 to the light source holding holder 20 will be described.
First, the light source 11 is inserted into the insertion hole 21 of the light source holding holder 20 shown in FIG. At this time, the light source 11 is mounted on the light source holding holder 20 in a state of being positioned in the Z-axis direction as shown in FIG.
Next, when the protrusions 31 to 33 are pressed by a caulking jig lowered from above the light source holding holder 20, the protrusions 31 to 33 are plastically deformed so as to cover the upper surface of the light source 11 as shown in FIG. Caulking and fixing. At this time, since the convex portions 23 to 25 are disposed in the regions S1 to S3 that are regions separated from the regions T1 to T3 illustrated in FIG. 7, the main body 28 when the projections 31 to 33 are pressed. Little effect of internal stress.

As described above, according to the light source holding holder 20 of the laser scanning optical device 1 provided in the image forming apparatus 1000 according to the present embodiment, the convex portions 23 to 25 provided in the seating surface portion 29 that is the mounting seating surface are the regions S1 to S3. The regions T1 to T3 are disposed at positions that do not overlap each other. That is, the convex portions 23 to 25 are disposed in the regions S1 to S3 that are regions that are separated from the regions T1 to T3 that are easily affected by the stress generated when the protrusions 31 to 33 are pressed and plastically deformed. The positional deviation is preferably suppressed.
Therefore, the light source holding holder 20, the laser scanning optical device 1, and the image forming apparatus 1000 according to the first embodiment have a light source holding holder that suppresses the displacement of the mounting seat surface when the light source is caulked and fixed to the light source holding holder. It can be said that it is a laser scanning optical apparatus and an image forming apparatus.

“Embodiment 2”
Next, the light source holding holder 20a according to the second embodiment will be described. In addition, about the following light source holding holder 20a, about the same structure as the light source holding holder 20 which concerns on Embodiment 1, the same code | symbol is attached | subjected and description is abbreviate | omitted and only a different point is demonstrated.

  As shown in FIG. 9, the light source holding holder 20 a includes three escape grooves 41 a to 43 a connected to the fitting groove 22 around the convex portions 23 to 25. The relief grooves 41a to 43a connect the positions where the convex portions 23 to 25 are disposed and the outer peripheral end of the main body portion 28 (half connecting the center C of the insertion hole 21 and the convex portions 23 to 25). Formed on a straight line). And the relief grooves 41a-43a isolate | separate the main-body part 28 below the projection parts 31-33 into three of the separation parts 44a-46a.

  When the projections 31 to 33 are pressed and plastically deformed by a caulking jig with respect to the light source holding holder 20a having such a configuration, stress is not generated in the light source holding holder 20a as shown in FIG. P is generated. However, since the said stress P generate | occur | produces inside the isolation | separation part 44a-46a, the convex-shaped parts 23-25 formed on the same straight line as the relief grooves 41a-43a should avoid the influence of the said stress P suitably. Can do. That is, it can be said that the relief grooves 41a to 43a are grooves for reducing the influence of stress on the convex portions 23 to 25 caused by pressing by the caulking jig.

  As described above, according to the light source holding holder 20a according to the second embodiment, the same effect as that of the light source holding holder 20 can be obtained, and of course, the relief grooves 41a to 43a can project the convex portions 23 to 25 more than the light source holding holder 20. The influence of stress can be reduced more suitably. That is, the convex portions 23 to 25 are more reliably prevented from being displaced due to the influence of stress.

"Modification 1"
Next, Modification 1 of the light source holding holder 20a according to the second embodiment will be described.
In the light source holding holder 20a, the escape grooves 41a to 43a are provided on the half line connecting the center C of the insertion hole 21 and the convex portions 23 to 25. However, as shown in the light source holding holder 20b in FIG. 28, relief grooves 41b to 43b may be provided so as to surround the peripheral surfaces of the protrusions 31 to 33 in the upper portion.
When the projections 31 to 33 are pressed and plastically deformed by the caulking jig with such a configuration, the stress P is directly below the projections 31 to 33 surrounded by the relief grooves 41b to 43b in the main body 28. appear. That is, the convex portions 23 to 25 provided at positions separated from the protrusions 31 to 33 can suitably avoid the influence of the stress P.

"Modification 2"
Next, a second modification of the light source holding holder 20a according to the second embodiment will be described.
In the light source holding holder 20a, the relief grooves 41a to 43a are connected to the fitting groove 22. However, as shown in the light source holding holder 20c in FIG. 11, the relief grooves 41c to 43c are formed in a part of the protrusions 31 to 33. It may be provided.
The relief grooves 41c to 43c are formed by cutting out a part of the lower end of each of the protrusions 31 to 33 (near the edge of the upper end of the fitting groove 22). When the protrusions 31 to 33 are pressed and plastically deformed by a caulking jig, the stress P is generated from the protrusions 31 to 33 excluding the portions cut out by the escape grooves 41c to 43c in the main body 28. Occurs in connected parts. That is, since the relief grooves 41c to 43c are formed, the stress P is generated at least at a position outside the escape grooves 41c to 43c inside the main body portion 28. Therefore, the position where the stress P is generated and the convex portions 23 to 23 are generated. It is sufficiently separated from the position of 25. As a result, the convex portions 23 to 25 can suitably avoid the influence of the stress P.

The description in the above embodiment is an example of a suitable light source holding holder, a laser scanning optical apparatus, and an image forming apparatus according to the present invention, and the present invention is not limited to this.
Further, the detailed configuration and detailed operation of each part of the light source holding holder, the laser scanning optical device, and the image forming apparatus in the above embodiments can be appropriately changed without departing from the spirit of the present invention.

  Specifically, for example, in the first modification, the escape grooves 41a to 43a are formed so as to connect the positions where the convex portions 23 to 25 are disposed and the outer peripheral end of the main body portion 28. As long as it is provided around 23 to 25, an appropriate change can be made. For example, the escape grooves 41a to 43a may be formed into grooves that surround the peripheral surfaces of the convex portions 23 to 25, such as escape grooves 41b to 43b that surround the peripheral surfaces of the protrusions 31 to 33 shown in FIG. .

1000 Image forming apparatus 1 Laser scanning optical apparatus 2 Optical housing 10 Light source part 11 Light source 12 Main body part 13 Flange part 14 Bottom face 15 Terminal 20 Light source holding holder 21 Insertion hole 22 Fitting groove 29 Seat surface parts 23-25 Convex parts 31-33 Projection (projection)
DESCRIPTION OF SYMBOLS 100 1st optical system 110 2nd optical system 120 Deflector 130 3rd optical system 140 4th optical system 150 Sensor 200 Photosensitive body 20a Light source holding holder 41a-43a Escape groove (groove)
20b Light source holding holder 41b-43b Escape groove (groove)
20c Light source holding holders 41c to 43c Escape groove (groove)

Claims (7)

A light source holding holder for holding a light source,
The main body,
An insertion hole for inserting the light source through the main body,
A convex surface on the upper surface, and a seating surface portion for positioning in the optical axis direction of the light source inserted in the insertion hole,
A protrusion protruding near the edge of the insertion hole on the upper surface of the main body, and plastically deforming so as to cover the upper surface of the light source inserted into the insertion hole by pressing;
With
The convex portion is a position where a region surrounding the convex portion and the center of the insertion hole does not overlap with a region surrounding the projection and the center of the insertion hole in a top view of the main body portion. A light source holding holder which is disposed in The light source holding holder according to claim 1,
A light source holding holder comprising a groove for reducing an influence of stress on the convex portion caused by pressing by the jig. The light source holding holder according to claim 2,
The light source holding holder, wherein the groove is formed around the convex portion in the seat surface portion. The light source holding holder according to claim 2,
The light source holding holder, wherein the groove is formed so as to surround a peripheral surface of the protrusion. The light source holding holder according to claim 2,
The light source holding holder, wherein the groove is formed in a part of the protrusion. A light source holding holder according to any one of claims 1 to 5, which holds a light source capable of emitting semiconductor laser light;
A first optical system for collimating semiconductor laser light emitted from the light source;
A second optical system for converting the semiconductor laser light collimated by the first optical system into convergent light in the sub-scanning direction;
A deflector for deflecting the semiconductor laser light converted into convergent light by the second optical system;
A third optical system for condensing the semiconductor laser light deflected by the deflector onto the photoreceptor;
A laser scanning optical device comprising:   An image forming apparatus comprising the laser scanning optical apparatus according to claim 6.

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