JP2008197563A - Polygon motor, and method for manufacturing polygon motor - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a polygon motor capable of enhancing productivity while maintaining basic performance required therefor, and to provide a method for manufacturing the polygon motor. <P>SOLUTION: This method comprises: a plating process for forming a plated layer on a plurality of mirror parts of a nest; an assembling process for assembling the nest into a metallic mold; a molding process for molding a composite molding by charging resin into the mold and integrating the plated layer having the plurality of mirror faces with a resin formed body; and a take-out process for taking out the composite molding from the mold. <P>COPYRIGHT: (C)2008,JPO&INPIT

Description

  The present invention relates to a polygon mirror, and more particularly to a polygon mirror that is rotationally driven by a spindle motor.

  2. Description of the Related Art Conventionally, some image generating apparatuses such as printers, facsimiles, and copiers, for example, generate an image using a polygon mirror. That is, the laser beam emitted from a predetermined laser light source on the mirror surface of the polygon mirror is reflected on the image imaging surface, and the reflected light beam emitted on the image imaging surface is rotated by rotating the polygon mirror with a spindle motor. The beam spot is scanned.

  The polygon mirror is usually manufactured as a structure having a plurality of mirror surfaces by performing ultra-precise cutting on a metal member such as an aluminum alloy. This cutting process has a very high shape accuracy of the processed surface, but has a drawback in that it takes a long time to process because it is an individual process for each mirror surface. Low cost requirements for component parts of image generation devices are increasing especially recently, and it is necessary to deal with this problem. To improve production efficiency by connecting multiple polygon mirrors and processing them at once. I have to.

  However, since such measures for improving production efficiency also use an individual processing technique called cutting, there is a limit to shortening the processing time, and further breakthroughs are required.

  One of such breakthrough ideas is a means of using a resin molded body, but other requirements required for a polygon motor, specifically, extremely high surface accuracy (surface roughness, flatness) in the mirror part, It is not possible to cope with all of the deformation limit and thinning during high-speed rotation.

As a compromise that meets many requirements, a structure in which a synthetic resin body is fitted inside a metal ring having a plurality of mirror portions has been proposed (for example, Patent Document 1).
JP 2003-57584 A

  However, in such a structure, the metal ring forming the mirror portion is still processed by cutting, which is not a fundamental solution for improving productivity. Moreover, there is a concern about the peeling between the fitted metal ring and the synthetic resin body.

  An object of the present invention is to provide a polygon motor and a method for manufacturing the same that overcome these problems and realize productivity improvement while maintaining the basic performance required for the polygon motor.

(Claim 1)
In order to solve the above problems, a polygon mirror manufacturing method according to the present invention includes a plating step of forming a plating layer on a plurality of mirror surface portions of a nest, an assembling step of incorporating the nest into a die, and a resin as a die A molding step of integrating the plating layer having a plurality of mirror surfaces and the resin molding into a composite molding, and a step of taking out the composite molding from the mold.

  According to this manufacturing method, since the plating layer is formed on the mirror surface portion of the insert in the plating step, the surface facing the mirror surface portion of the plating layer is transferred to the mirror surface and becomes a mirror surface. In the molding process, the plating layer having this mirror surface is integrated with the resin molded body to form a composite molded body. When the mirror surface part of the nesting and the plating layer are peeled off in the extraction process, the shape of the mirror surface part of the nesting is transferred. A composite molded body having a plated layer having a plurality of mirror surfaces is obtained.

  That is, by adopting such a manufacturing method, it is possible to efficiently obtain a mirror surface having high shape accuracy without individually cutting the mirror surface of the polygon mirror. Moreover, unlike the structure in which the surface of the resin molded body is coated with a reflecting surface, the mirror surface is hardly deformed due to the resin deformation even at high speed rotation, and high shape accuracy is maintained.

Therefore, the polygon mirror manufactured by such a manufacturing method achieves both high shape accuracy and high productivity.
The mirror surface portion formed in the nesting may be a part of the surface including the mirror surface portion, for example, only the laser scanning region. Also in this case, the entire surface of the plating layer formed by transferring the surface including the mirror surface portion is referred to as a “mirror surface”.

(Claim 2)
In the manufacturing method, the plating layer may be an annular structure having an outer surface composed of a plurality of mirror surfaces.

  In such a structure, the plurality of mirror surfaces of the plating layer are integrated with adjacent mirror surfaces. For this reason, it is difficult to cause a deviation in the positional relationship between adjacent mirror surfaces, and a highly accurate polygon mirror with a small laser scanning blur width can be obtained.

(Claim 3)
In the manufacturing method according to claim 1 or 2, the mirror surface of the plating layer may have a curved surface portion.

  Since the plating layer forms an annular structure as a whole, it is possible to strictly define the positional relationship between adjacent mirror surfaces. Therefore, if a curved surface portion is provided on the mirror surface to widen the scanning width of light on a predetermined projection surface or make the scanning speed of light constant, the polygon mirror and the optical axis correcting optical element (fθ It is possible to reduce the distance between the optical element and the aspherical component of the optical axis correcting optical element.

(Claim 4)
In addition to the structure of the said Claim 1 to 3, the anchor part which improves the adhesive force with a resin molding may be formed in the plating layer.

When such a manufacturing method is employed, the plating layer is prevented from dropping from the resin molded body during the manufacturing process or during use.
In particular, when the plating layer has the configuration of claim 2, the annular plating layer suppresses dimensional shrinkage of the resin molded body accompanying the curing of the resin in the molding step. For this reason, even if slight fluctuations occur in the molding conditions (especially curing conditions) and the shrinkage force fluctuates, the fluctuations are absorbed by the rigidity of the plating layer and are not likely to appear as changes in the shape of the mirror surface of the polygon mirror. Become. Therefore, it is possible to obtain a polygon mirror with stable quality.

(Claim 5)
In addition to the structure of claim 4, the plating layer has a non-planar portion in a surface adjacent to the mirror surface (hereinafter simply referred to as “adjacent surface”) as an anchor portion, and the resin is formed in the molding step. By covering the non-planar portion, peeling between the plating layer and the resin molded body may be suppressed.

  An example of the non-planar part is a concavo-convex shape. When the resin molding shrinks in the center direction as the resin hardens in the molding process, the resin generates a force that moves the entire plating layer toward the center, and this force is applied to the back surface of the mirror surface of the plating layer. It works in the direction of reducing the adhesion between the plating layer and the resin. However, if there is a concavo-convex shape on the adjacent surface, the concavo-convex portion of the resin formed corresponding to this concavo-convex shape is engaged with the adjacent surface, and the entire plating layer is drawn toward the center. Therefore, peeling between the plating layer and the resin hardly occurs, and a highly reliable polygon mirror can be obtained.

  In particular, when the plating layer is annular as in claim 2, the biting at the adjacent surface suppresses the shrinkage of the resin, and the amount of dimensional shrinkage due to curing is much higher than that without the plating layer. Less. Since the dimensional change is suppressed in this way, the deviation between the center of gravity of the manufactured polygon motor and the designed center of gravity is reduced, and the stability during high-speed rotation is increased.

(Claim 6)
In the manufacturing method according to claims 1 to 5, the mirror surface portion on which the nested plating layer is formed may be formed of a coating layer mainly composed of stainless steel and / or chromium.

  In this manufacturing method, the plating layer formed on the surface of the nesting is separated between the nesting surface and the plating layer in the take-out step, and is used as a member constituting a mirror surface. Therefore, the surface of the insert is required to be able to form a plating layer and to be easily peeled off. A surface of a material containing chromium can be cited as a material that satisfies this requirement. As a specific example, by using stainless steel or a coating layer mainly composed of chromium by vapor deposition or chromium plating, the plating layer, particularly a nickel-based plating layer, can be separated without deteriorating the shape of the interface. Is realized. Therefore, a polygon mirror having excellent surface accuracy can be obtained by using the nesting structure.

(Claim 7)
In the manufacturing method according to claims 1 to 6, the plating layer may be made of nickel or a nickel-based alloy.

Plating made of nickel or a nickel-based alloy (hereinafter abbreviated as “nickel plating”) has a high hardness and can be easily set to a thickness of 100 μm. Therefore, by using nickel plating as a plating layer, unlike an aluminum polygon mirror or a polygon mirror in which a metal (for example, aluminum) is coated on a resin, there is no need to form an antireflection layer such as SiO ₂ , Simplification is realized. In addition, since a thick plating layer can be formed, the strength as a structure is high, and the mirror surface is hardly deformed when rotated as a polygon motor at high speed. Furthermore, when the plating layer has an annular structure as in claim 2, high rigidity can be realized as the structure, and deformation of the mirror surface is further suppressed. Further, in the case of suppressing the curing shrinkage of the resin molded body on the adjacent surface as in claim 5, the shape stability is particularly high because the rigidity of the plating layer is high, and the center of gravity of the manufactured polygon motor and the design The deviation from the center of gravity is extremely small, and the stability during high-speed rotation is particularly enhanced.

(Claim 8)
8. The manufacturing method according to claim 1, wherein the rotary shaft member or the rotary bearing member is placed in a mold in the assembling step, and the rotary shaft member or the rotary bearing member is also integrated with the resin molded body in the molding step. You may make it do.

  By employing such a manufacturing method, it is possible to manufacture a polygon motor having a mirror surface and a rotating shaft or a rotating bearing in a single resin molding step. Since it is manufactured in a single process without going through an assembly process, the positional relationship between the mirror surface, which is a component of the polygon motor, and the rotary shaft or rotary bearing can be managed with high accuracy. It is possible to obtain a polygon motor with high productivity.

  A shaft may be used as the rotating shaft member, and a cylindrical member or a cup-shaped member may be used as the rotating bearing member. A non-planar portion, for example, an uneven portion may be provided on the outer surface of the portion disposed on the resin inner surface of these members as appropriate to prevent these members from falling off the resin molded body.

(Claim 9)
In the assembling step of the manufacturing method according to claim 8, a shaft having a coating layer formed on at least the outer surface is incorporated, and the shaft is integrated with the resin molded body in the molding step, and then the shaft is pulled out to cover the coating layer. You may make it form the bearing part containing.

  When such a manufacturing method is used, the inner surface of the coating layer after drawing the shaft substantially maintains the processing accuracy of the outer surface of the shaft, so that the processing accuracy is much higher than the processing accuracy obtained by ordinary internal grinding or the like. Obtaining a rotary bearing in the radial direction is realized. Further, when a coating layer is formed also on the top of the shaft, a thrust bearing portion having a highly accurate machining surface is formed at the bottom in the opening of the coating layer after the shaft is pulled out. That is, by employing the above manufacturing method, it is possible to manufacture a polygon mirror including a rotary bearing portion having high shape accuracy.

In addition, since the thin coating layer formed on the shaft constitutes the rotary bearing portion, the polygon mirror can be reduced in weight.
(Claim 10)
In addition to the configurations of the first to ninth aspects, the plating thickness of the scanning light passage region on the mirror surface of the plating layer may be 200 μm or more.

  By adopting such a configuration, the rigidity of the mirror portion becomes sufficiently high, deformation in the molding process and the extraction process is unlikely to occur, and deformation during use is unlikely to occur. Therefore, it is possible to obtain a high-quality polygon mirror with less optical axis shake. In particular, when the plating layer is annular, the deformation of the plating layer due to the shrinkage force of the resin during the curing process in the molding process is suppressed to a minimum, and a particularly high quality polygon mirror can be obtained.

(Claim 11)
In this way, the polygon mirror manufactured by the manufacturing method according to any one of claims 1 to 10 has a mirror-plated surface formed on the mirror-finished nest, and therefore needs to perform mirror-surface cutting on each surface. There is no, and productivity is high. Further, using a resin composite molding technique, the plating layer constituting the mirror surface is further “assembled” with the rotating shaft member or the rotating bearing member on the resin structure forming the main body of the polygon mirror as necessary. For this reason, the polygon motor manufactured by the present manufacturing method achieves both extremely high productivity and high assembly accuracy.

(Claim 12)
The invention of claim 12 provided to solve the above-described problems includes an annular plating structure having an outer surface composed of a plurality of mirror surfaces, and a resin structure disposed in a hollow portion of the annular plating structure. And a rotating shaft member or a rotary bearing member fixed to the resin structure so as to have the center of gravity of the main body including the resin structure and the plating structure, and a mirror that forms the outer surface of the plating structure A non-planar portion including a concave portion and / or a convex portion is formed on a surface adjacent to the surface, and at least a part of the non-planar portion is a polygon mirror covered with a resin structure.

  According to said structure, the some mirror part of a plating structure becomes what integrated with the adjacent mirror part. For this reason, it is difficult to cause a deviation in the positional relationship between adjacent mirror surfaces, and a highly accurate polygon mirror with a small laser scanning blur width can be obtained.

  Further, the resin formed so as to cover at least a part of the non-planar portion including the concave portion and / or the convex portion on the adjacent surface of the mirror surface holds the plating structure in the non-planar portion, and the resin plating structure Suppresses peeling. In addition, when the resin structure is formed by resin molding, the resin contraction force generated during the curing process prevents the resin from contracting in the center direction, resulting in a composite molded body with less dimensional shrinkage. It is done.

  Furthermore, the rotary shaft member or the rotary bearing member can be made of a material different from the resin. For example, when a hard material such as metal is used, it is possible to obtain a rotary shaft or rotary bearing that obtains high dimensional accuracy. .

(Claim 13)
In addition to the above configuration, the main body portion may include a magnetizing member fixed to the resin structure, and a rotational motion may be performed using the magnetizing member as a rotor.

  Magnetic poles that are different in the circumferential direction on the side surface between the plating structure and the rotary shaft member or rotary bearing member of the polygon motor where the protrusion of the rotary shaft member or the opening of the rotary bearing member is provided. If the magnetizing members are fixed so as to be alternately arranged, the rotor is built into the polygon mirror. Therefore, if the rotating bearing or rotating shaft to which the stator is fixed is installed so as to face the surface on which the polygon mirror magnetizing member is disposed, the polygon motor can be rotated by controlling the current to the stator. Is done. The magnetizing member may be fixed by, for example, arranging the magnetizing member together with the plating structure and the shaft or the bearing in a mold at the time of resin molding and performing composite molding. Alternatively, the magnetizing member may be fixed to a part of the polygon motor by molding a resin containing a magnetic material in two colors.

  As described above, according to the present invention, since the plating surface formed on the mirror-finished insert is used as a mirror surface, it is not necessary to perform mirror surface cutting on each surface. For this reason, the polygon mirror according to the present invention has high productivity. In the present invention, the plating layer constituting the mirror surface is “assembled” to the resin structure constituting the main body of the polygon mirror by using a resin composite molding technique. In addition, a rotary shaft member or a rotary bearing member can be assembled as necessary. For this reason, the polygon mirror according to the present invention achieves both extremely high productivity and high assembly accuracy.

  In addition, when the plating layer has an annular structure and a shape that suppresses curing shrinkage of the resin molded body is provided on the surface adjacent to the mirror surface that forms the outer surface thereof, the resin molded body is cured. Since the dimensional change of the polygon mirror due to the shrinkage becomes extremely small, a polygon motor having high stability at the time of high-speed rotation can be obtained which almost coincides with the center of gravity of the product and the center of gravity at the design stage.

Hereinafter, embodiments of the present invention will be described with reference to the drawings. However, the present invention is not limited to the following embodiments.
[Embodiment 1]
The polygon mirror which concerns on 1st embodiment of this invention, its manufacturing method, and those modifications are demonstrated using FIGS.

(Figure 1)
FIG. 1A is a perspective view conceptually showing a polygon mirror according to a first embodiment of the present invention, and FIG. 1B is a plane perpendicular to the rotation axis of the polygon mirror, and A in FIG. It is sectional drawing in the surface containing a -A 'line, (c) is sectional drawing in the surface containing the AA' line of the rotating shaft of a polygon mirror, and (a).

<Overall structure>
The polygon mirror 0101 according to the first embodiment of the present application includes an annular plating structure 0105 having an outer surface composed of a plurality of mirror surfaces 0103 and a resin structure 0106 disposed in a hollow portion of the annular plating structure 0105. And a rotating shaft member 0104 (0107) fixed to the resin structure 0106 so that the center of gravity of the main body portion 0102 including the resin structure 0106 and the plating structure 0105 is contained.

<Plating structure>
In the present embodiment, the plating structure 0105 is formed by nickel plating. Since nickel plating has high hardness, the plating surface can be used as it is as a mirror surface. On the other hand, the aluminum metal polygon mirror and the resin polygon mirror according to the prior art need to be coated with a transparent hard material such as SiO ₂ in order to protect the mirror surface. In addition, as nickel plating, in addition to plating with pure Ni, alloy plating such as Ni—P, Ni—B, and Ni—W may be used.

  In this embodiment, the plating structure 0105 has an annular structure in which all the mirror surfaces 0103 of the polygon mirror 0101 are integrated. The annular structure has a structure divided into a plurality of parts. Also good. However, in the case of a plating structure in which adjacent mirror surfaces are different from each other, it is necessary to strictly control the positional relationship, and the load of the assembly process is often increased. Therefore, it is preferable to form an annular structure as shown in FIG.

  In addition, although six mirror surfaces 0103 are provided as an example, the number of mirror surfaces is three or more and is determined by design, and may be other than six. Further, in FIG. 1, the mirror surface 0103 is formed so as to be parallel to the axial direction of the rotating shaft member 0104. However, the mirror surface 0103 is formed to have a predetermined angle with respect to the rotating shaft member 0104 according to a design requirement. May be. In this case, the outer shape of the entire plating structure 0105 is a polygonal frustum, and it is difficult to control the tilt angle of the mirror surface except for the annular integrated structure.

<Resin molding>
In FIG. 1, the resin molded body 0106 is provided with a lightening structure as shown in FIG. When the polygon mirror according to the present embodiment is manufactured by using a manufacturing method by composite molding as described later, the shrinkage amount of the resin molded body 0106 can be reduced by providing the lightening structure. It is. For this reason, deformation of the plating structure 0105 due to resin shrinkage is suppressed to a minimum, and the surface shape of the mirror surface does not easily change even if there is a slight change in molding conditions. Therefore, it is possible to obtain a polygon mirror with stable quality.

  In addition, the provision of the thinning structure relatively reduces the moment of inertia, and the motor requires less driving force. Therefore, it is possible to reduce the size of the polygon motor.

The resin material of the resin structure 0106 used in the present embodiment may be mainly composed of a thermosetting or photocurable resin, or may be mainly composed of a thermoplastic resin.
Thermosetting resins include phenolic resin (PF), epoxy resin (EP), melamine resin (MF), urea resin (urea resin, UF), unsaturated polyester resin (UP), alkyd resin, polyurethane (PUR), An example is polyimide (PI). A curing agent such as an acid anhydride may be added to these thermosetting resins, or a resin, glass, metal, ceramics, or the like may be dispersed as a filler.

  As the thermoplastic resin, any of general-purpose plastic, engineering plastic, and super engineer plastic may be used, or composite plastic in which resin, glass, metal, ceramics, and the like are dispersed may be used.

General-purpose plastics include polyethylene (PE), high density polyethylene (HDPE), medium density polyethylene (MDPE), low density polyethylene (LDPE),
Polypropylene (PP), polyvinyl chloride (PVC), polyvinylidene chloride, polystyrene (PS), polyvinyl acetate (PVAc), polytetrafluoroethylene (PTFE), ABS resin (acrylonitrile butadiene styrene resin), AS resin, acrylic resin (PMMA) is exemplified.

  Engineering plastics include polyacetal (POM), polyamide (PA), polycarbonate (PC), modified polyphenylene ether (m-PPE), polybutylene terephthalate (PPB), polyethylene terephthalate (PET), ultra high molecular weight polyethylene (UHPE), Examples include cyclic polyolefin (COP).

  Super engineering plastics include polyphenylene sulfide (PPS), polysulfone (PSF), polyethersulfone (PES), amorphous polyarylate (PAR), liquid crystal polyester (LCP), polyetheretherketone (PEEK), polyamideimide (PAI). ), Polyimide (PI), polyetherimide (PEI), fluororesin and the like.

  The polygon mirror receives heat from the motor unit, and the heat received by the polygon mirror is increasing due to the trend of speeding up and downsizing of the motor. From this viewpoint and from the viewpoint of securing rigidity during high-speed rotation, it is preferable to use super engineering plastics such as liquid crystal polyester (LCP). Further, although the polygon mirror of the present embodiment has a structure that reduces the influence of heat shrinkage of the resin, it is preferable to use a resin having a small heat shrinkage rate because the stability of the shape is increased.

<Rotating shaft>
The rotating shaft member 0104 may be made of a metal material such as stainless steel, or may be made of a ceramic material such as alumina or zirconia. Alternatively, a metal-inorganic composite material such as super steel may be used. In addition, a solid lubricant film may be formed on a portion of the rotary shaft member 0104 that faces the rotary bearing portion. Furthermore, in the case of oil lubrication, a group of fine holes that become oil pockets may be formed, and in the case of an air bearing, a groove for generating dynamic pressure may be formed.

(Figure 2)
FIG. 2 is a partially enlarged view of the upper left end region of the cross-sectional view of FIG.
As shown in FIG. 2, the plating structure 0201 has a recess 0204 in a surface (hereinafter abbreviated as “adjacent surface”) 0203 adjacent to the mirror surface 0202. On the other hand, the peripheral portion 0206 of the resin molded body 0205 is formed so as to cover the adjacent surface 0203, and the concave portion 0204 is filled with resin in the peripheral portion 0206 to form a convex portion 0207.

  In FIG. 2, only one adjacent surface 0203 is shown, but a similar concave portion is formed on the other adjacent surface opposite to this, and a resin molded body is formed so as to cover the adjacent surface. The recess is filled with resin.

  By having such a structure, the plating structure 0201 is prevented from being separated from the resin molded body 0205 during high-speed rotation. As long as the protruding portion 0207 has a protruding height of about 50 μm and a protruding width of about 50 μm, the holding function of the plated structure 0201 can be sufficiently exerted.

  Here, since the resin molded body 0205 is formed by curing a liquid or semi-solid resin as will be described later, a force to shrink the volume is often generated during the curing. This force acts to pull the plating structure 0201 to the center side of the resin molded body 0205 and to the right side in FIG. 2 by the resin convex part 0207 filled in the concave part 0204, thereby suppressing separation of the plating structure 0201. become.

  In the present embodiment, the concave portion 0204 is formed on the adjacent surface 0203, but a convex portion may be formed on the contrary, or an uneven shape may be formed. If a non-planar portion including at least one of the concave portion and the convex portion is formed, it is possible to prevent the plating structure 0201 from being separated from the resin molded body 0205.

  Further, the entire two adjacent surfaces 0203 of all the mirror surfaces 0202 may be covered with the peripheral edge 0206 of the resin molded body 0205, or some of the plurality of mirror surfaces 0202 may not be covered. . Alternatively, there may be a portion that is not covered by a part of the adjacent 0203. However, in this case, it is preferable that the contact area of the peripheral edge 0206 with the adjacent surface 0203 is not greatly different between the adjacent adjacent surfaces. This is because a strong surface tilting force may be applied to the mirror surface, and the optical axis may be shaken as a polygon motor.

(Figure 3)
FIG. 3 is a partial perspective view showing only one mirror surface and its peripheral region in a modification of the polygon mirror according to the present embodiment.

  In the polygon mirror 0301 according to this modification, the mirror surface has a mirror surface portion 0302 and a non-mirror surface portion 0303, and the mirror surface portion 0302 is formed so as to include the incident laser scanning line. In the case of such a configuration, since the mirror processing area of the mirror surface is small, the processing time can be shortened.

  Hereinafter, one of the methods for manufacturing the polygon mirror according to the present embodiment will be described with reference to FIGS. In this manufacturing method, a plating step of forming a plating layer on a plurality of mirror surface portions of the insert, an assembling step of incorporating the insert into a mold, and plating having a plurality of mirror surfaces by introducing resin into the mold A molding step in which the layer and the resin molding are integrated to form a composite molding, and a removal step of taking out the composite molding from the mold.

(Fig. 4)
FIG. 4A is a perspective view conceptually showing a nesting for manufacturing the polygon mirror according to the first embodiment of the present invention, and FIG. 4B is a central axis of the hollow portion of the nesting and FIG. It is sectional drawing in the surface containing line BB '.

<Nested structure>
As shown in FIG. 4 (a), the insert 0401 has a hollow portion 0402 having a shape corresponding to the mirror surface of the polygon mirror at the center of the substantially disc-shaped main body, and an inner surface composed of a plurality of quadrangles thereof. In 0403, the entire surface is mirror-finished for each surface.
When only a part of each surface of the inner surface 0403 is mirror-finished, a polygon mirror as shown in FIG. 3 is obtained.

(Fig. 5)
FIG. 5A is a perspective view conceptually showing a modified example of the nesting for manufacturing the polygon mirror according to the first embodiment of the present invention, and FIG. 5B shows the nesting according to the modified example. (C) is a perspective view conceptually showing a processing example of a mirror surface portion of the section.

  As shown in FIG. 5, the insert 0501 according to the present modification is not integrated, and each section 0502a, 0502b, 0502c,... May be divided so as to have one mirror surface portion 0503.

  In this case, since the mirror surface portion 0503 is processed not as an inner surface but as an outer shape, it can be processed using ultra-precise cutting based on the prior art. It is also possible to connect the mirror surface portions 0503a, 0503b, 0503c,... Of a plurality of sections 0502a, 0502b, 0502c,.

(Fig. 6, 7, 8)
6A and 6B are cross-sectional views conceptually showing the manufacturing process of the polygon mirror according to the present embodiment, wherein FIG. 6A shows the nesting after mirror finishing, and FIG. 6B shows the masking member attached to the nesting. (C) shows a state in which a plating layer is formed on the mirror surface of the nesting, (d) shows a state in which the nesting in which the plating layer is formed is separated from the masking member, and (e) shows the nesting. And the state which installed the shaft in the metal mold | die is shown, (f) has shown the state with which resin was filled in the metal mold | die.

A manufacturing process of the polygon mirror will be described with reference to FIG.
<Plating process>
First, plate-like masking members 0603 having hollow portions set based on the polygon mirror shape are fixed to both end surfaces of a nest 0601 in which an inner side surface 0602 as shown in FIG. 6A is mirror-finished. (FIG. 6B). The masking member 0603 has a function of preventing the plating layer from being formed on both end faces of the insert 0601 in the next step and defining the shape of the plating layer formed on the mirror surface 0602, particularly the shape of the adjacent surface.

  The material of the insert 0601 may be metal or ceramic, but at least the inner surface 0602 is required to have conductivity. Considering the ease in the extraction process as the final process, the surface of the material containing chromium is preferable. By using a coating layer mainly composed of stainless steel or chromium, as a specific example, a coating layer formed by vapor deposition or chromium plating, the plating layer is easily peeled off while having conductivity. Therefore, it is difficult to cause scratches at the interface between the plating layer and the nesting surface or to deteriorate the surface shape of the mirror surface in an extraction step described later.

  On the other hand, the material of the masking member 0603 may be any material as long as it is a non-conductor. When a masking member is used a plurality of times, a fluorine-based material (for example, PTFE) that is difficult to adhere to plating is preferable, but if not reused, it is preferable to use a material that is injection-molded using a general-purpose resin such as PE. .

  (A) of FIG. 7 is the elements on larger scale which show the mirror surface part of the nesting shown in FIG.6 (b), and the edge part of a masking member, (b) is the mirror surface part of the nesting shown in FIG.6 (c), It is the elements on larger scale which show a plating layer and the edge part of a masking member.

  As shown in FIG. 7, the shape made by the inner surface of the masking member 0603 is slightly smaller than the shape made by the inner surface 0602 of the insert 0601. For this reason, when the masking member 0603 and the insert 0601 are fixed so that the centers of their inner side surfaces are aligned, a step is generated on both inner side surfaces. Further, a convex portion 0701 is formed at the step portion of the masking member 0603 so as to protrude toward the hollow portion side of the insert 0601. A gap 0702 is formed between the convex portion 0701 and the inner side surface 0602 of the insert 0601. ing.

  The dimensions of the convex portion 0701 and the gap 0702 are determined by the shape of the polygon motor and the like, but the protruding height and protruding width and the gap width of the protruding portion may be about 50 μm. In addition, it is preferable that conductivity is imparted to the inner peripheral side (about 50 μm in width) of the gap 0702, the convex portion 0701, and the convex portion 0701 of the masking member 0603. In the next plating step, plating also grows from above the convex portion 0701, and this concave portion is easily formed.

  Subsequently, the hollow portions of the insert 0601 and the masking member 0603 are filled with a plating solution, an anode is disposed in the hollow portion, and plating is performed using the insert 0601 as a cathode. As described above, the plating is preferably composed mainly of nickel. Alternatively, a plurality of members composed of the nest 0601 and the masking member 0603 may be stacked, the plating solution may be filled in the hollow portion formed by these stacked members, and the anode may be disposed for plating. In this case, the formation of the plating layer 0604 on the inner surface 0602 of the plurality of inserts 0601 can be realized by a single plating process.

  As a result of the plating step, a plating layer 0604 is formed on the inner side surface 0602 as shown in FIG. The plating layer 0604 is an annular plating structure, and the outer surface of the annular plating structure has a mirror surface because the shape of the inner surface 0602 of the insert 0601 is inverted and transferred. Further, a concave portion 0703 corresponding to the convex portion 0701 of the masking member 0603 is formed on the surface adjacent to the outer surface (see FIG. 7B).

Here, the thickness of the plating layer 0604 is preferably 100 μm or more. If it is less than 100 μm, the flatness of the mirror surface may deteriorate during rotation due to insufficient rigidity.
Considering the viewpoint of securing rigidity as the plating structure, it is particularly preferable that the thickness is 200 μm or more. If it has a thickness of 200 μm or more, it is avoided that the shape of the mirror surface is deformed to be uncontrollable by contraction deformation regardless of the type of resin.

  Subsequently, when the masking member 0603 is removed from the insert 0601, the insert 0601 in which the plating layer 0604 is formed on the inner surface 0602 as shown in FIG. 6D is obtained. Moreover, the plating layer 604 has an annular structure, and a concave portion 0703 is formed on the adjacent surface of the outer surface.

<Incorporation process>
Next, as shown in FIG. 6 (e), the insert 0601 is placed in a cavity of a mold composed of an upper mold 0605 and a lower mold 0606. As a result, in the cavity, the outer surface and both end surfaces of the insert 0601 are in close contact with the mold, and the upper mold and the lower mold hollow section are continuous above and below the hollow portion of the insert 0601, respectively. Thus, one hollow portion 0607 is formed.

Further, the lower mold 0606 is provided with an opening, and the shaft 0608 is disposed in the opening so that a part thereof protrudes into the hollow portion 0607.
At this time, by arranging the center of gravity of the shape formed by the hollow portion 0607 and the center of gravity of the shaft 0608 so as to coincide with each other, a polygon mirror that is less likely to be affected by shaft shake even at high speed rotation can be obtained. Specifically, the opening diameter of the opening portion of the lower mold 0606 is set to be about 50 μm larger than the outer diameter of the shaft 0608, and a plurality of micrometers are protruded in the radial direction within the opening portion. Are previously installed in the opening of the lower mold 0606. And the position of the shaft 0608 inserted in the opening is finely adjusted by changing the protruding amount of the tip of the micrometer.

<Molding process>
When the insert 0601 and the shaft 0608 are thus arranged at appropriate positions in the mold, a liquid or semi-solid resin is introduced into the hollow portion 0607, and energy for cooling or curing is supplied to change the physical state to a solid. And change.

Then, when the resin is solidified, the resin takes in the plating layer 0604 and the shaft 0608, and as shown in FIG. 6 (f), the resin molded body 0609 becomes a composite molded body with these members.
In the shaft 0608, an uneven shape may be imparted to a portion taken into the resin molded body 0609. By having such a shape, the shaft 0608 is prevented from falling off from the resin molded body 0609.

FIG. 8 is a partially enlarged view showing the adjacent surface of the plating layer and the resin molded body in the composite molded body shown in FIG.
Since the resin molded body 0609 is formed so as to fill the hollow portion 0607, the resin molded body 0609 is also filled on the adjacent surface of the plating layer 0604 and the concave portion 0802 formed on the adjacent surface. As a result, the resin molded body 0609 is formed so as to cover the adjacent surface and so that the convex portion 0801 as the inverted shape of the concave portion 0802 is engaged with the concave portion 0802.

  As described above, since the resin may be a thermosetting or photo-curing resin or a thermoplastic resin, the resin is cured by cooling, heating, or supply of energy such as light. When cooling or heating is used as a trigger, the mold material may be made of a general metal. When energy supply such as light is used as a trigger, the entire mold is made of a light-transmitting material such as glass. Alternatively, only the supply portion may be made of a light transmissive material while being made of metal.

<Removal process>
As shown in FIG. 6 (f), when a composite molded body formed of the resin molded body 0609, the plating layer 0604, and the shaft 0608 is formed, the composite molding is performed by peeling at the interface 0803 between the nesting 0601 and the plating layer 0604. Separate body from nesting 0601.

  As shown in FIG. 8, the plating layer 0604 is in close contact with the resin at three sides other than the interface 0803 and is physically engaged with the resin molded body by the recess 0802 on the adjacent surface. For this reason, the shrinkage force generated in the resin molded body 0609 is transmitted to the plating layer 0604 by the concave portion 0802, and a force in the direction separating from the insert 0601 is applied to the plating layer 0604. Therefore, when the shaft 0608 is held and pulled out, peeling at the interface 0803 occurs preferentially, and the composite molded body is taken out as the polygon mirror 0101.

The shrinkage force generated in the resin molded body 0609 can be controlled by various methods.
First, it can be changed depending on the type of resin, and can also be changed depending on the shape of the resin molded body 0609. For example, the contraction force can be reduced by providing a lightening structure. The plating layer 0604 has a relatively low rigidity at the center of the mirror surface due to its shape, and a relatively high rigidity at the joint portion with the adjacent mirror surface, that is, at the corner. For this reason, when the resin molding 0609 has a uniform structure, the central portion having low rigidity is preferentially deformed over the corner portion, and the mirror surface tends to be a concave mirror shape. Therefore, by providing a hollow structure in the radial direction for the portion of the resin molded body 0609 that contacts the central portion of the mirror surface, the shrinkage force of the resin molded body 0609 at this portion is reduced, and the concave mirror shape is deformed. Suppression is realized. Alternatively, in consideration of the deformation of the concave mirror type, the inner side surface 0602 of the insert 0601 is processed in advance into a concave mirror type, and when the mirror surface of the plating layer that is a convex mirror type by reverse transfer is taken out, it is just flat. It may be made to become.

  In this way, it is possible to control the contraction force at the design stage, but it can also be varied depending on the molding conditions. If the resin filling amount at the time of injection is increased or injection compression molding is performed, the shrinkage force decreases. Moreover, if the cooling process is adjusted, partial contraction force fluctuations are possible. Specifically, if a portion having a slow cooling rate is provided, the shrinkage can be induced there. Therefore, by lowering the cooling rate of the upper and lower end faces of the polygon mirror 0101 to induce the shrinkage in this region. It is possible to suppress shrinkage of the resin molded body 0609 on the side facing the mirror surface.

  The specific operation of the removal step is to separate the upper mold 0605 and the lower mold 0606 to expose the composite molded body, and then to remove the composite molded body from the mold, and the procedure may be set as appropriate. For example, the upper mold 0605 or the lower mold 0606 may be moved, the insert 0601 and the composite molded body may be separated from the mold, and the insert 0601 and the composite molded body may be separated, or one mold may be moved and combined. After exposing the molded body, the composite molded body may be taken out so that the insert 0601 remains in the mold.

<Modification of mirror surface>
Here, as a modification of the polygon mirror 0101 manufactured by this manufacturing method, a case where the mirror surface 0103 has a non-planar shape will be described. The mirror surface of a general polygon mirror has a planar shape. This is because the normal manufacturing method directly cuts the mirror surface, so that the processing time becomes too long when a complicated shape processing is performed. However, if the above manufacturing method is adopted, it is possible to obtain a large number of duplicates with high accuracy by processing one master, that is, a nest. Therefore, even if it takes time to process the master, the influence on the manufacturing time per replica is small, and it is possible to manufacture a polygon mirror having a non-planar mirror surface with high productivity.

  For example, if the curved surface portion is provided on the mirror surface to increase the light scanning width on the predetermined projection surface, the interval between the polygon mirror and the optical axis correcting optical element (such as the fθ lens) can be reduced. Further, if the scanning speed of light on the projection surface is made constant, the aspherical component of the optical axis correcting optical element can be removed. Reducing the optical path length in an image generation device is an important development issue. By making the mirror surface of the polygon mirror non-planar, the optical path length can be reduced, greatly contributing to downsizing of the image generation device. To do.

[Embodiment 2]
Subsequently, a polygon mirror according to a second embodiment of the present invention will be described with reference to FIGS. However, since both the configuration and the manufacturing method are common to the first embodiment, the differences will be mainly described.

(Fig. 9)
FIG. 9A is a perspective view conceptually showing a polygon mirror according to the second embodiment of the present invention, and FIG. 9B is a plane perpendicular to the rotation axis of the polygon mirror, and is shown in FIG. It is sectional drawing in the surface containing -C 'line, (c) is sectional drawing in the surface containing the CC' line of (a) and the rotating shaft of a polygon mirror.

<Overall structure>
A polygon mirror 0901 according to the second embodiment includes an annular plating structure 0904 having an outer surface composed of a plurality of mirror surfaces 0903, and a resin structure 0905 disposed in a hollow portion of the annular plating structure 0904. And a rotary bearing member 0906 fixed to the resin structure 0905 so that the center of gravity of the main body portion 0902 including the resin structure 0905 and the plating structure 0904 is included. Accordingly, the polygon mirror 0901 according to the present embodiment includes a hollow portion 0907 into which a rotation shaft is inserted at the center, and the inner surface of the hollow portion 0907 functions as a radial bearing, and the bottom surface 0908 functions as a thrust direction bearing. .

<Manufacturing method>
The main difference between the polygon mirror according to this embodiment and the polygon mirror according to the first embodiment is whether it has a rotary bearing part or a rotary shaft part. Therefore, the manufacturing method is also mainly different in a portion where the rotary bearing portion is formed in the resin molded body.

(Fig. 10)
FIG. 10 is a cross-sectional view conceptually showing the manufacturing process of the polygon mirror according to the second embodiment, wherein (a) shows a state in which the insert in which the plating layer is formed is separated from the masking member, (B) shows the state in which the shaft on which the insert and the coating layer are formed is installed in the mold, (c) shows the state in which the resin is filled in the mold, and (d) is taken out from the mold. A state of the composite molded body before the shaft is pulled out is shown.

Hereinafter, the manufacturing process will be described with reference to FIG.
First, as shown in FIG. 10A, a plating layer 1002 is formed on the inner side surface that forms the mirror surface of the insert 1001. At that time, using the masking member, a recess is formed on the surface adjacent to the outer surface of the plating structure made of the plating layer 1002 as in the manufacturing method according to the first embodiment.

  Next, the insert 1001 in which the plating layer 1002 is formed is placed in the cavity of the mold. Since this installation method is also the same as that of the first embodiment, description thereof is omitted. At this time, as shown in FIG. 10B, the shaft 1004 is inserted into the opening of the mold, and a coating layer 1005 by plating is formed on the protrusion into the mold cavity. .

When resin molding is performed in this state, as shown in FIG. 10C, the resin molded body 1006 is integrated with the plating layer 1002 and the coating layer 1005 to form a composite molded body.
When the composite molded body is taken out of the mold together with the shaft 1004, a polygon mirror with the shaft 1004 as shown in FIG. 10D is obtained, so the shaft 1004 is pulled out to expose the interface with the coating layer 1005. Thus, the polygon mirror 0901 having the rotary bearing member 0906 is obtained.

  By adopting such a manufacturing method, it is possible to easily obtain the metallic rotating bearing member 0906 having processing accuracy substantially equal to the processing accuracy of the shaft 1004. Comparing the outer diameter processing of the shaft and the inner surface processing of the hole, in general, higher processing accuracy can be easily obtained by the outer diameter processing. A coating layer 1005 is formed on the shaft 1004 subjected to such high-precision processing on the outer diameter to form a coating layer 1005. After the coating layer 1005 is combined with the resin molded body 1006, the shaft 1004 is pulled out. Thus, a composite molded body having a metallic opening with extremely high processing accuracy on the inner surface is obtained.

  In order to obtain the same processing accuracy by other methods, it is necessary to prepare a cup-shaped member having a thickness of mm made of metal, and to polish the inner surface by taking a considerable number of man-hours. In this way, it is extremely difficult to obtain a degree of cylindricity that can achieve high-speed stable rotation, and the cup-shaped member is much heavier than the coating layer 1005 formed by plating. Nevertheless, it may increase the moment of inertia or cause a runout.

  In the above manufacturing method, the material of the coating layer 1005 by plating is preferably a material mainly made of nickel like the plating layer 1002, and the thickness thereof is 50 μm or more, preferably 100 μm or more, particularly preferably. Is 150 μm or more. When the thickness is 500 μm or more, it is difficult to control the stress of the coating layer, and there is a risk of peeling during resin molding. Moreover, since the time required for plating becomes long, it is disadvantageous from the viewpoint of productivity.

  The material of the shaft 1004 is the same as the material of the insert 1001, and preferably has a surface made of a material containing chromium so that plating can be easily peeled off. Specific examples include stainless steel and chromium-deposited or plated surfaces.

[Embodiment 3]
Subsequently, a polygon mirror according to a third embodiment of the present invention is shown in FIG.
Will be described. However, since both the configuration and the manufacturing method are common to the first embodiment, the differences will be mainly described. FIG. 11 is a sectional view conceptually showing the main part of a polygon motor provided with a polygon mirror according to the third embodiment of the present invention.

  As in the first embodiment, the polygon motor 1101 shown in FIG. 11 includes a polygon mirror 1102 in which a plating structure having a mirror surface and a rotating shaft member 1103 are fixed by a resin structure. However, in the present embodiment, a ring-shaped permanent magnet 1104 is fixed as a magnetizing member on the end surface of the polygon mirror 1102 on the side from which the rotating shaft member 1103 protrudes, and the N and S poles are alternately arranged on the permanent magnet 1104. Instead, a plurality of poles (for example, 12 poles) are magnetized.

  The protruding portion of the rotating shaft member 1103 in the polygon mirror 1102 is inserted into the hollow portion of the rotating bearing member 1105 to form a radial bearing. Further, the tip of the projecting portion of the rotating shaft member 1103 is in contact with the sliding member 1106 fixed in the hollow portion of the rotating bearing member 1105 to form a thrust bearing.

  In this state, a stator coil 1107 is fixed to the outer portion of the rotary bearing member 1105 so as to face the permanent magnet 1104 fixed to the polygon mirror 1102. By controlling the current flowing through the stator coil 1107, a force in the circumferential direction of the rotating shaft is generated in the permanent magnet 1104 fixed to the polygon mirror 1102, and the polygon motor 1101 can be rotated.

  By incorporating the rotor in the polygon mirror 1102 in this way, it is possible to reduce the thickness of the entire polygon motor and contribute to the miniaturization of the entire optical unit.

  In this embodiment, the permanent magnet 1104 has a ring shape and the end face is exposed. However, the permanent magnet 1104 may have any form as long as the polygon mirror 1102 fixes the rotor of a normal polygon motor in the resin structure. Therefore, instead of the ring-shaped magnet, a plurality of piece-like magnets corresponding to the magnetic poles may be fixed, or the magnets may be embedded without being exposed. Alternatively, a magnetizable metal piece as well as a magnet may be fixed.

  As a method for fixing the magnetized member to the resin structure, it is preferable because the resin structure is manufactured by a resin molding technique and fixed by simultaneously molding a magnet or a metal piece at the time of resin molding because it is simple and highly accurate. . Alternatively, if it is manufactured by two-color molding of a resin containing a magnetic material and a resin constituting the resin structure, it is possible to fix the magnetized member very easily and with its mass balance being precisely controlled. Therefore, it is particularly preferable.

  In this embodiment, the polygon mirror 1102 has the rotation shaft portion 1103. However, a polygon mirror having a rotation bearing portion may be used, and the stator 1107 may be attached to the corresponding rotation shaft.

  As described above, according to the present invention, since individual cutting is not required for each mirror surface of the polygon mirror, the productivity of the polygon mirror is high. In addition, since the plating layer constituting the mirror surface, the rotary shaft member or the rotary bearing member, and the rotor are “assembled” to the resin structure forming the main body of the polygon mirror using the resin composite molding technology, Such a polygon mirror achieves both extremely high productivity and high assembly accuracy.

  In addition, when the plating layer has an annular structure and a shape that suppresses curing shrinkage of the resin molded body is provided on the surface adjacent to the mirror surface that forms the outer surface thereof, the resin molded body is cured. Since the dimensional change of the polygon mirror due to the shrinkage becomes extremely small, a polygon motor having high stability at the time of high-speed rotation can be obtained which almost coincides with the center of gravity of the product and the center of gravity at the design stage.

  That is, according to the present invention, it is provided that a polygon motor that is excellent in stability at high-speed rotation and that can downsize not only the main body but also the optical unit can be manufactured with high productivity.

(A) is the perspective view which showed notionally the polygon mirror which concerns on 1st embodiment of this invention, (b) is a surface perpendicular | vertical to the rotating shaft of a polygon mirror, and is AA of (a). It is sectional drawing in the surface containing a 'line, (c) is sectional drawing in the surface containing the rotating shaft of a polygon mirror and the AA' line of (a). It is the elements on larger scale of the upper left area of sectional drawing of FIG.1 (c). It is the fragmentary perspective view which displayed only one mirror surface and its peripheral area | region about the modification of the polygon mirror which concerns on 1st embodiment.

(A) is the perspective view which showed conceptually the nesting for manufacturing the polygon mirror which concerns on 1st embodiment of this invention, (b) is the center axis | shaft of the hollow part of nesting, and B of (a) It is sectional drawing in the surface containing -B 'line. (A) is the perspective view which showed notionally the modification of the nesting for manufacturing the polygon mirror which concerns on 1st embodiment of this invention, (b) is the section of the section which comprises the nesting concerning a modification It is one perspective view, (c) is a perspective view which shows notionally the example of a process of the mirror surface part of the section. It is sectional drawing which showed notionally the manufacturing process of the polygon mirror which concerns on 1st embodiment of this invention, Comprising: (a) shows the nesting after completion | finish of mirror surface processing, (b) attaches a masking member to a nesting (C) shows a state in which a plating layer is formed on the mirror surface portion of the insert, (d) shows a state in which the insert in which the plating layer is formed is separated from the masking member, and (e) A state in which the insert and the shaft are installed in the mold is shown, and (f) shows a state in which the resin is filled in the mold.

(A) is the elements on larger scale which show the mirror surface part of the nesting shown by FIG.6 (b), and the edge part of a masking member, (b) is the mirror surface part of the nesting shown by FIG.6 (c), a plating layer, It is the elements on larger scale which show the edge part of a masking member. It is the elements on larger scale which show the adjacent surface of the plating layer and resin molding in the composite molded object shown by FIG.6 (f). (A) is the perspective view which showed notionally the polygon mirror which concerns on 2nd embodiment of this invention, (b) is a surface perpendicular | vertical to the rotating shaft of a polygon mirror, and is CC of (a). It is sectional drawing in the surface containing a 'line, (c) is sectional drawing in the surface containing the rotating shaft of a polygon mirror, and CC' line of (a).

It is sectional drawing which showed notionally the manufacturing process of the polygon mirror which concerns on 2nd embodiment of this invention, Comprising: (a) shows the state which isolate | separated the nesting in which the plating layer was formed from the masking member, ( b) shows a state in which the shaft on which the insert and the coating layer are formed is installed in the mold, (c) shows a state in which the resin is filled in the mold, and (d) shows a composite taken out from the mold A state of the molded body before the shaft is pulled out is shown. It is sectional drawing which showed notionally the principal part of the polygon motor provided with the polygon mirror which concerns on 3rd embodiment of this invention.

Explanation of symbols

0101 Polygon mirror 0102 Resin molded body 0103 Mirror surface 0104 Rotating shaft 0105 Plating structure 0401 Nesting

Claims (13)

A plating step of forming a plating layer on a plurality of mirror surface portions of the nesting,
An assembly process for incorporating the insert into the mold;
A molding step of introducing a resin into the mold and integrating the plating layer having a plurality of mirror surfaces and the resin molded body to form a composite molded body;
A method for producing a polygon mirror, comprising: taking out the composite molded body from the mold. The method of manufacturing a polygon mirror according to claim 1, wherein the plating layer is an annular structure having an outer surface composed of a plurality of mirror surfaces.   The method of manufacturing a polygon mirror according to claim 2, wherein the mirror surface of the plating layer has a curved surface portion.   The manufacturing method of the polygon mirror in any one of Claim 1 to 3 in which the anchor part which improves the adhesive force with the said resin molding is formed in the said plating layer. The plating layer has a non-planar portion in a plane adjacent to the mirror surface as the anchor portion, and the resin covers the non-planar portion in the molding step so that the plating layer and the resin molded body are in close contact with each other. 5. The method for manufacturing a polygon mirror according to claim 4, wherein the force is improved.   The method for manufacturing a polygon mirror according to any one of claims 1 to 5, wherein a portion where the plating layer is formed in the nest includes a coating layer mainly composed of stainless steel and / or chromium.   The method for manufacturing a polygon mirror according to claim 1, wherein the plating layer is made of nickel or a nickel-based alloy. In the assembling step, the rotary shaft member or the rotary bearing member is placed in the mold,
The method for manufacturing a polygon mirror according to claim 1, wherein the rotary shaft member or the rotary bearing member is also integrated with the resin molded body in the molding step. In the assembling step, a shaft having a coating layer formed on at least the outer surface is incorporated,
9. The method of manufacturing a polygon mirror according to claim 8, wherein after the shaft is integrated with the resin molded body in the molding step, the shaft is pulled out to form a bearing portion including the coating layer.   The method for manufacturing a polygon mirror according to claim 1, wherein the plating thickness of the scanning light passage region on the mirror surface of the plating layer is 200 μm or more.   A polygon mirror manufactured by the manufacturing method according to claim 1. An annular plating structure having an outer surface comprising a plurality of mirror surfaces;
A resin structure disposed in a hollow portion of the annular plating structure;
A rotary shaft member or a rotary bearing member fixed to the resin structure so as to have a center of gravity of a main body including the resin structure and the plating structure;
A surface adjacent to the mirror surface that forms the outer surface of the plating structure is formed with a non-planar portion including a concave portion and / or a convex portion, and at least a part of the non-planar portion is covered with the resin structure. Polygon mirror characterized by The main body includes a magnetized member fixed to the resin structure,
The polygon mirror according to claim 12, wherein rotational movement is performed using the magnetized member as a rotor.

Images