JPH09243951A - Metal mold for production of rotary polyhedral mirror made of synthetic resin and apparatus for producing rotary polyhedral mirror made of synthetic resin as well as production of rotary polyhedral mirror made of synthetic resin - Google Patents

Abstract

PROBLEM TO BE SOLVED: To enable the uniform pressure distribution of reflection surfaces and to improve the flatness of the reflection surfaces and the flatnesses of the reflection surfaces and a mounting reference plane. SOLUTION: A compression core is divided to a mounting reference plane compression core 152 and a reflection surface compression core 153 which are respectively independently controlled. The external shape line 153' at the reflection surface compression core 153 is arranged the outer side than the virtual extension line 12' of the external shape line of the reflection surface 12 or near the outer side. A mirror finished surface liner 154 has a tapered part extending outward from the lower part of the reflection surface 12 and transmits the compressive force of the reflection surface compression core 153 to the reflection surface 12.

Description

Detailed Description of the Invention

[0001]

TECHNICAL FIELD The present invention relates to copying, faxing,
In a printer, a bar code scanner, etc., a synthetic resin rotary polygon mirror manufacturing die for manufacturing a synthetic resin rotary polygon mirror used for rotating and deflecting incident light, and a synthetic resin rotary polygon mirror manufacturing apparatus, and The present invention relates to a method for manufacturing a rotary polygon mirror made of synthetic resin.

[0002]

2. Description of the Related Art As a conventional means for manufacturing a rotary polygon mirror made of synthetic resin, injection molding or injection compression molding is generally used. In the injection compression molding method, it is preferable to directly compress the reflecting surface as the compression direction of the resin. However, the above-mentioned injection compression molding method has problems that the distance from the center line of the mounting hole to the scanner to each reflecting surface varies, the mold becomes large, and the like. Therefore, in the above injection compression molding method, the surface perpendicular to the reflection surface (reference surface side for mounting on the scanner)
It is the actual situation that is compressed.

FIG. 8 is a view for explaining the principle of the injection compression molding method in the conventional example. In FIG. 8, a synthetic resin rotary polygon mirror 81 is obtained by injecting a synthetic resin between a fixed mold 80, a movable compression core 85, and a mirror insert 86. In addition, a synthetic resin rotary polygon mirror 81
In the injection compression molding, the reflecting surface 82 transferred by the mirror surface insert 86 and the hole 84 into which the rotating shaft (not shown) is fitted are molded. The rotary polygon mirror 81 made of synthetic resin is used in the compression core 8 in the injection compression molding.
5 is compressed in the direction perpendicular to the dividing surface 87,
The mounting compression surface 83 is molded. The reflecting surface 82 of the synthetic resin rotary polygon mirror 81 is compressed by the compression force direction 88.
And a smooth surface is transferred by the mirror surface insert 86.

FIG. 9A is an external view of a conventional rotary polygon mirror made of synthetic resin, and FIG. 9B is a front view of the rotary polygon mirror made of synthetic resin. In FIG. 9, a rotary polygon mirror 8 made of synthetic resin is shown.
1 is a reflecting surface 82, a mounting compression surface 83, a mounting hole 84,
It is composed of a mounting end surface 89 ′ and a mounting reference surface 89. FIG. 10 is a view for explaining a state in which a synthetic resin rotary polygon mirror in a conventional example is attached. In FIG. 10, the rotary polygon mirror 81 made of synthetic resin is the rotor yoke 10
1 is mounted on a mirror receiving pedestal 102 that is integrally formed with the rotor 1.
3 is attached by a leaf spring 104 and a C ring 105. A rotating shaft 103 ′ formed on the lower surface of the rotor yoke 101 is rotatably fixed to a bearing 108 fixed to the housing 107 together with the printed board 106. The printed circuit board 106 has a drive coil (not shown) printed thereon, and the rotary polygon mirror 8 made of synthetic resin
1 is rotated and its rotation speed is controlled.

Further, as a conventional means for manufacturing a rotary polygon mirror made of synthetic resin, for example, "injection compression molding method and injection compression molding die" in JP-A-4-176622.
Relates to the size of the compression core, and the outline of the compression core is arranged at a position of 0.1 mm to 5 mm inside the outline of the reflection surface. In the rotary polygon mirror made of synthetic resin obtained by the above-mentioned manufacturing means, the dimension of the compression core is appropriate, so that the side surface precision of the molded product is greatly improved.

[0006]

In recent years, as the resolution of copying machines and laser beam printers has increased, synthetic resin rotary polygon mirrors are required to have higher precision. At the same time, the synthetic resin rotary polygon mirror is expected to significantly reduce the manufacturing cost as compared with the conventional metal rotary polygon mirror. The precision of this rotary polygon mirror made of synthetic resin directly affects the print image quality, and thus requires ultra-precision. In particular, it is an important issue to ensure the accuracy of the flatness of the reflecting surface of the rotary polygon mirror made of synthetic resin. Currently, the precision of the flatness of the reflecting surface required for the rotary polygonal mirror made of synthetic resin is in the range of about 0.1582 μm to 0.09 μm, which directly affects the print image quality, and therefore is very strictly required. There is.

As a method for manufacturing a rotary polygon mirror made of synthetic resin, injection molding or injection compression molding is generally used as described above. In the injection molding method, a plurality of pin gates are provided at a position close to the reflecting surface in order to avoid pressure loss due to the flow length as much as possible, but there is a problem that welds are generated by the pin gates. Next, the injection compression molding method includes a full compression mold in which a mold is closed at a high pressure after filling a resin, and a core compression mold in which a movable core is locally compressed. The injection compression molding method is suitable for those that require precision, such as a rotary polygon mirror made of synthetic resin.

When the rotary polygon mirror made of synthetic resin is manufactured by the injection compression molding method, since it is compressed from the normal mounting reference plane, as shown in FIG.
3 and become vertical. As a result, the synthetic resin rotary polygon mirror 8
Although it is somewhat different depending on the thickness of No. 1, a sufficient compression force is transmitted to the surface facing the compression core 85, whereas a sufficient compression force is not transmitted to the reflecting surface 82 that is perpendicular thereto. In this case, the accuracy of the portion where the compression force acts vertically and the portion where the compression force extends are improved. However, the reflective surface 8
2, the vertical surface with respect to the attachment reference surface 83 has a small compression effect.

When the compression pressure is increased in order to expand the range of the compression force, the resin at the compression stage becomes
Due to the progress of solidification, extra residual stress is left on the rotary polygon mirror made of synthetic resin. As a method for removing such residual stress, the method described in Japanese Patent Laid-Open No. 176622/1992 has a flatness of the reflecting surface of 0.3 μm.
However, the accuracy is not as high as desired.

Further, since the injection compression molding method compresses the mounting reference surface side, it is difficult to satisfy both the mounting reference surface and the reflecting surface at the same time, and one of them must be prioritized. have. Therefore, the accuracy of the reflective surface is usually given priority, but as a result,
Due to the above-mentioned reason, the pressure is excessively applied, which deteriorates the flatness of the mounting reference surface. As a problem that may occur when the flatness of the mounting reference surface is deteriorated, there is a problem that the tilt angle of each reflecting surface with respect to the mounting reference surface cannot be secured. Further, as a problem of the mold for manufacturing the rotary polygon mirror made of synthetic resin, the mirror surface insert which is incorporated in the mold and transfers the reflection surface has a flatness with a limit accuracy which can be currently processed. Is made. Therefore, there is a problem that the flatness of the mirror surface insert is easily deformed by a slight external force. For this reason, it is necessary to keep the pressure during compression to a minimum level.

The present invention is intended to solve the above problems, and the outline of the compression core is located outside or near the outside of the virtual extension of the outline forming the reflecting surface of the rotary polygon mirror made of synthetic resin. An object of the present invention is to provide a disposed synthetic resin rotary polygon mirror manufacturing die, a synthetic resin rotary polygon mirror manufacturing apparatus, and a synthetic resin rotary polygon mirror manufacturing method. The present invention also provides a synthetic resin rotary polygon mirror manufacturing die, a synthetic resin rotary polygon mirror manufacturing apparatus, and a synthetic resin rotary polygon mirror, in which the reflective surface compression core and the attachment reference surface compression core can be independently controlled. It is intended to provide a manufacturing method. Furthermore, the present invention is a synthetic resin rotary polygon mirror manufacturing die, and a synthetic resin rotary polygon mirror manufacturing device, in which a pressure transmitting portion is provided outside and below the reflection surface of the synthetic resin rotary polygon mirror. Another object is to provide a method for manufacturing a rotary polygon mirror made of synthetic resin.

[0012]

[Means for Solving the Problems]

(First Invention) In order to achieve the above object, a mold for manufacturing a rotary polygon mirror made of synthetic resin according to the present invention has a hole 1 for fitting a rotary shaft.
6, the plurality of reflecting surfaces 12 formed on the outer peripheral surface, and the mounting reference surface 14 are injection-compression-molded. The compression-core to be injection-compression-molded has a contour line made of synthetic resin. The polygonal mirror 11 is characterized in that it is arranged outside the virtual extension line 12 'of the outline forming the reflecting surface 12 of the polygonal mirror 11 or near the outside of the virtual extension line 12'.

(Second Invention) The compression core in the synthetic resin rotary polygon mirror manufacturing die of the present invention includes a mounting reference plane compression core 152 capable of independently compressing and controlling the mounting reference plane 14 and the reflecting surface 12. The reflective surface compression core 153 is included.

(Third Invention) The attachment reference surface compression core 152 and the reflection surface compression core 153 in the synthetic resin rotary polygon mirror manufacturing die of the present invention are arranged coaxially with the rotation axis, and at least one of them is plural. It is characterized by comprising a compressed core of.

(Fourth invention) The synthetic resin rotary polygon mirror manufacturing die according to the present invention reflects the synthetic resin rotary polygon mirror 11 by the reflecting surface compression core 153 for compressing the reflecting surface 12 and the mirror surface insert 154. The compressive pressure transmitting portion 13 that transmits the compressive force to the surface 12 is the reflecting surface 12 of the rotary polygon mirror 11 made of synthetic resin.
It is characterized in that it is provided on the lower side.

(Fifth Invention) A mirror surface insert 154 for compressing the reflecting surface 12 in the mold for manufacturing a rotary polygon mirror made of synthetic resin according to the present invention includes a transfer surface for compressing the reflecting surface 12 and the compression pressure transmitting portion 13. And a taper portion to be formed.

(Sixth Invention) A synthetic resin rotary polygon mirror manufacturing apparatus of the present invention includes a hole 16 into which a rotary shaft is fitted, a plurality of reflecting surfaces 12 formed on an outer peripheral surface, and a mounting reference surface 14. A synthetic resin rotary polygon mirror 11 made of is injection-molded, and a fixed die 151 for molding the upper surface of the synthetic resin rotary polygon mirror 11 and a mounting reference surface 14 of the synthetic resin rotary polygon mirror 11 are compressed. At the same time, the mounting reference surface compression core 152 that can be controlled independently, the reflecting surface 12 of the rotary polygonal mirror 11 made of synthetic resin, and the reflection surface compression core 153 that can be controlled independently, and the rotary polygonal mirror 11 made of synthetic resin can be controlled independently. And a mirror surface insert 154 having a compression pressure transmitting portion 13 for transmitting the compressive force to the reflecting surface 12 together with the reflecting surface compression core 153.

(Seventh Invention) In the method for manufacturing a rotary polygon mirror made of synthetic resin according to the present invention, a hole 16 into which a rotary shaft is fitted, a plurality of reflecting surfaces 12 formed on the outer peripheral surface, and a mounting reference surface 14 are provided. The injection molding is performed on the rotary polygonal mirror 11 made of a synthetic resin, and the thermoplastic synthetic resin is injected into a molding die including a fixed die 151, a mirror surface insert 154, and at least two compression cores, and then the synthetic resin is synthesized. The mounting reference surface 14 of the resin rotary polygon mirror 11 is compressed by at least one compression core, and the reflecting surface 12 of the synthetic resin rotary polygon mirror 11 is compressed.
And the compression pressure transmitting portion 13 of the mirror insert 154 outside the virtual extension line 12 'of the outline forming the reflecting surface 12 or near the outside of the virtual extension line 12', and the outline line of at least one other compression core. A method for manufacturing a rotary polygon mirror made of synthetic resin, wherein 153 'is arranged and compressed.

[0019]

BEST MODE FOR CARRYING OUT THE INVENTION First, since the reflecting surface of a synthetic resin rotary polygon mirror is compressed by a compression core provided below a virtual extension of the outline of the reflecting surface, the same surface side as the mounting reference surface. Even if the compression force is from, it is possible to compress at a position closer to the reflection surface. Furthermore, the reflecting surface of the rotary polygon mirror made of synthetic resin is provided with a compression pressure transmitting portion outside below the virtual extension line of the outline of the reflecting surface, so that the pressure applied to the outside of the reflecting surface outline is transmitted to the reflecting surface. , The compression pressure is efficiently transmitted to the reflection surface. As a result, the direction of pressure is parallel to the reflection surface, which is no different from the conventional method, but the compression force of the compression core is concentrated on the reflection surface by concentrating the compression pressure on the reflection surface. To improve the flatness of the reflecting surface.

Further, the compression pressure transmitting portion in the rotary polygonal mirror made of synthetic resin allows the compression force of the compression core to be applied to the lower portion of the mirror insert. As a result, the compression pressure transmitting section prevents excessive pressure from being applied to the mirror surface insert of the mold, and prevents deformation of the flatness of the mirror surface insert. Further, the attachment reference surface compression core for ensuring the flatness of the attachment reference surface and the reflection surface compression core for ensuring the reflection surface flatness are arranged coaxially, and each is independently controlled. . As described above, the reason why these compression cores can be controlled independently of each other is that when the compression force of the compression core is transmitted to the reflection surface, it is significantly larger than the optimum compression pressure for the mounting reference surface. This is to reduce this residual stress as much as possible.

When the reflecting surface and the mounting reference surface of the synthetic resin rotary polygon mirror are compressed by one compression core as in the conventional case, the accuracy of the reflecting surface and the mounting reference surface accuracy of the synthetic resin rotary polygon mirror are Was difficult to secure at the same time. Therefore, according to the present invention, the compression core for the reflecting surface and the compression core for the mounting reference surface are divided into a plurality of parts, and an optimum compression pressure is set for each surface, whereby the reflecting surface and the mounting reference surface are set. It has become possible to obtain a rotary polygon mirror made of synthetic resin that satisfies the flatness of both surfaces.

[0022]

1 is a view for explaining the principle of the injection compression molding method according to the present invention. In FIG. 1, a synthetic resin rotary polygon mirror 11 includes a fixed mold 151 and a mirror surface insert 154 having a reflecting surface compression surface 15 composed of a tapered portion at a lower portion thereof.
It is obtained by injecting a synthetic resin between the movable reference mounting surface compression core 152 and the reflection surface compression core 153. Further, the synthetic resin rotary polygon mirror 11 is
In the injection compression molding, the reflecting surface 12 transferred by the mirror surface insert 154 and the hole 16 into which a rotation shaft (not shown) is fitted are molded. Further, in the above-mentioned synthetic resin rotary polygonal mirror 11, in the injection compression molding, the mounting reference surface compression core 152 serves as the mounting reference surface 14, and the reflecting surface compression core 153 serves as the contour line virtual extension line 12 'of the reflecting surface 12. The lower surface is compressed in the direction perpendicular to the dividing surface 28. Further, the outline 153 ′ of the reflecting surface compression core 153 is arranged outside or near the outside of the virtual extension line 12 ′ of the outline on the reflecting surface 12.

The mounting reference surface 14 of the synthetic resin rotary polygon mirror 11 is compressed by the reference surface compression core 152,
The mounting reference surface 14 is transferred by the force in the direction of the arrow 17. Further, the reflecting surface 12 of the synthetic resin rotary polygon mirror 11 is caused by the compressive force in the direction perpendicular to the dividing surface 28 of the reflecting surface compressing core 153, and the reflecting surface compressing surface 1 of the mirror insert 154 is
5, the compressive force is applied to the reflecting surface 12 by the force in the direction of the arrow 18. As a result, the rotary polygon mirror 11 made of synthetic resin has the compression pressure transmitting portion 13 extending outward from the lower portion of the reflecting surface 12, and the mirror surface of the mirror insert 154 is the reflecting surface 12.
Is transferred to

FIG. 2 is a view for explaining a specific manufacturing method for injection compression molding the rotary polygon mirror made of synthetic resin according to the present invention. In FIG. 2, the synthetic resin is sprue 26.
Through the mold, and is injected into the mold constituted by the fixed mold 151, the mirror surface insert 154, the attachment reference surface compression core 152, and the reflection surface compression core 153. After a predetermined amount of synthetic resin is injected into the mold, the gate cutting device 27 moves up to stop the introduction of the synthetic resin, and a hole for inserting a rotary shaft (not shown) of the synthetic resin rotary polygon mirror 11 into the hole. 16 is molded. After that, the attachment reference surface compression core 152 and the reflection surface compression core 153 compress the attachment reference surface 14 and the reflection surface 12 of the rotary polygonal mirror 11 made of synthetic resin at predetermined independent pressures.

The rotary polygon mirror 11 made of synthetic resin is obtained by disassembling the fixed mold 151 and the movable mold 25 with the dividing surface 28 as a boundary after the synthetic resin is solidified. FIG.
(A) is an external view of the synthetic resin rotary polygon mirror in the present embodiment, and (B) is a front view of the synthetic resin rotary polygon mirror.
In FIG. 3, a synthetic resin rotary polygonal mirror 11 includes, for example, a synthetic resin main body having an integrally formed hexagonal outer shape, and a mounting hole 16 for inserting a shaft having a circular cross section into the central portion of the main body. A plurality of reflecting surfaces 12 adjacent to each other at each ridge angle on the side surface of the body, a mounting reference surface 14 similar to the body, and a mounting reference end surface 14 '.
And a compression pressure transmitting portion 13 composed of a taper portion extending outward from immediately below the reflecting surface 12.

The compression pressure transmitting portion 13 is the reflection surface compression core 1
As a result of 53 moving forward in a plane perpendicular to the outline of the reflecting surface 12,
It has a role of preventing interference with the mirror insert 154. In addition, the compression pressure transmitting portion 13 has a mirror surface insert 15
By releasing the pressure transmitted to the lower part of 4 in the direction of the reflecting surface 12, effective pressure is transmitted to the reflecting surface 12, and at the same time, releasing this pressure from the lower part of the mirror insert 154, the deformation of the mirror insert 154 by the compression pressure. Is being prevented. Further, the compression pressure transmitting portion 13 is transferred by the tapered surface 13 ′ formed on the mirror surface insert 154. The rotary polygon mirror 11 made of synthetic resin as described above is shown in FIG.
Similarly, is mounted on a mirror receiving pedestal formed on the rotor yoke by a leaf spring or the like.

FIG. 4 is a diagram for explaining the relationship between the rotary polygon mirror made of synthetic resin and the compression core according to an embodiment of the present invention. In FIG. 4, for example, a hexagonal rotary polygon mirror 11 made of synthetic resin has a similar compression pressure transmission portion 13 extending outward from immediately below the reflecting surface 12. Also, the dotted line 41
Is an outline 153 ′ of the reflecting surface compression core 153, which has a similar shape to the outline of the reflecting surface 12 and is arranged outside the virtual extension line 12 ′ of the outline. The dotted line 42
Attachment reference surface Attachment reference surface or attachment reference end surface 1 surrounded by a circular dotted line on the outline 152 ′ of the compression core 152
4 (14 ') can be compressed.

FIG. 5 is a view for explaining the relationship between the synthetic resin rotary polygon mirror and the compression core in another embodiment of the present invention. 5 is different from FIG. 4 in that the contour line 42 of the mounting reference surface compression core 152 is circular and the mounting reference surface or the mounting reference end surface 14 (14 ′) is substantially the same. FIG. 6 is a diagram for explaining the relationship between the synthetic resin rotary polygon mirror and the compression core according to another embodiment of the present invention. 6 is different from FIG. 5 in that the outline 41 of the reflecting surface compression core 153 is circular and is arranged outside the virtual extension line 12 ′ of the outline of the reflecting surface 12.

FIG. 7 is a view for explaining another embodiment of the present invention in which a plurality of mounting reference surfaces and a plurality of reflecting surface compression cores are provided. In FIG. 7, the compression core for manufacturing the synthetic resin rotary polygon mirror 11 includes two mounting reference plane compression cores 152 that are coaxial with the mounting hole 16.
162, and two reflecting surface compression cores 15 that are also coaxial
3, 163. Although not shown, each of these compression cores is configured so that the pressing force is independently controlled. Rotating polygon mirror 11 made of synthetic resin
Mounting reference surface 14 or mounting reference end surface 1
4'can be turned upside down as shown in FIG. It is preferable to decide which side should be used as the reference surface in consideration of the rotational balance of the rotary polygon mirror 11 made of synthetic resin.

Further, the reflecting surface compression core 153 has an inner periphery in a position in contact with the mounting reference surface compression core 152, and an outer periphery outside by about 3 mm from a virtual extension line 12 'of the outline of the reflecting surface 12, 12 and the similar shape are good. The reflecting surface compression core 153 in the large-sized synthetic resin rotary polygon mirror 11 does not need to be in contact with the outer periphery of the attachment reference surface compression core 152. The drive source of the attachment reference surface compression core 152 and the reflection surface compression core 153 may be on the mold side, but it is preferably on the injection compression molding machine side in order to avoid an increase in the size of the mold. The mounting reference plane compression core 15 is used when the reference plane accuracy in the injection compression molding machine is loose or when the synthetic resin rotary polygon mirror 11 has a small diameter.
Although the two and the reflective surface compression cores 153 are divided into two in FIG. 7, they may be increased to three, four, ...

[0031]

According to the present invention, by arranging the contour line of the compression core outside the virtual extension line of the contour line on the reflecting surface, a uniform pressure distribution on the reflecting surface becomes possible, and the flatness of the reflecting surface becomes flat. It has become possible to obtain a rotary polygon mirror made of good synthetic resin. According to the present invention, the compression core is provided with the reflection surface compression core and the attachment reference surface compression core, and these are independently controlled to thereby improve the flatness of the reflection surface and the attachment reference surface. It became possible to obtain a rotary polygon mirror. According to the present invention, the taper portion extending outward from directly below the reflecting surface of the synthetic resin rotary polygon mirror is used as the compression pressure transmitting portion, thereby releasing the pressure transmitted to the lower portion of the mirror surface nest in the direction of the reflecting surface, At the same time as transmitting an effective pressure to the reflecting surface, this pressure is released from the lower part of the mirror insert, preventing deformation of the mirror insert due to compressive pressure.

[Brief description of drawings]

FIG. 1 is a diagram for explaining the principle of an injection compression molding method according to the present invention.

FIG. 2 is a diagram for explaining a specific manufacturing method when injection-compressing the synthetic resin rotary polygon mirror in the present invention.

3A is an external view of a synthetic resin rotary polygon mirror in this embodiment, and FIG. 3B is a front view of the synthetic resin rotary polygon mirror.

FIG. 4 is a diagram for explaining the relationship between a synthetic resin rotary polygon mirror and a compression core in one embodiment of the present invention.

FIG. 5 is a view for explaining the relationship between a synthetic resin rotary polygon mirror and a compression core in another embodiment of the present invention.

FIG. 6 is a view for explaining the relationship between a synthetic resin rotary polygon mirror and a compression core in another embodiment of the present invention.

FIG. 7 is a view for explaining an example in which a plurality of mounting reference surfaces and a plurality of reflecting surface compression cores are provided in yet another embodiment of the present invention.

FIG. 8 is a diagram for explaining the principle of an injection compression molding method in a conventional example.

9 (a) is an external view of a conventional synthetic resin rotary polygon mirror, and FIG. 9 (b) is a front view of the synthetic resin rotary polygon mirror.

FIG. 10 is a diagram for explaining a state in which a synthetic resin rotary polygon mirror in a conventional example is attached.

[Explanation of symbols]

11 Synthetic resin rotating polygon mirror, 12 Reflective surface, 1
2'A virtual extension of the outline of the reflecting surface, 13 compression pressure transmitting portion, 13 'tapered surface, 14, 14'
Mounting reference surface (reference end surface), 15 reflective surface compression surface,
16 holes, 25 movable types, 151 fixed types, 1
52,162 Mounting reference plane compression core, 153,163
Reflective surface compression core, 153 'Reflective surface compression core outline, 154 Mirror surface nesting.

Claims (7)

[Claims] 1. A mold for manufacturing a rotary polygon mirror made of synthetic resin, wherein a hole for fitting a rotary shaft, a plurality of reflecting surfaces formed on an outer peripheral surface, and a mounting reference surface are injection-compressed and molded. The compression core to be compression-molded is arranged such that the outline of the compression core is outside the virtual extension line of the outline forming the reflecting surface of the synthetic resin rotary polygon mirror, or near the outside of the virtual extension line. A mold for manufacturing rotating polygon mirrors made of synthetic resin. 2. The synthetic resin according to claim 1, wherein the compression core comprises an attachment reference surface compression core and a reflection surface compression core capable of independently controlling compression of the attachment reference surface and the reflection surface. Mold for manufacturing rotary polygon mirrors. 3. The synthetic resin according to claim 2, wherein the attachment reference surface compression core and the reflection surface compression core are arranged coaxially with a rotation axis, and at least one of them is composed of a plurality of compression cores. Mold for manufacturing rotating polygon mirrors. 4. A reflection surface compression core for compressing the reflection surface and a compression pressure transmission portion for transmitting a compressive force to the reflection surface of the synthetic resin rotary polygon mirror by means of a mirror surface nest, the reflection surface of the synthetic resin rotary polygon mirror. The mold for manufacturing a rotary polygon mirror made of synthetic resin according to claim 1, wherein the mold is provided on a lower side portion. 5. The combination according to claim 4, wherein the mirror surface insert for compressing the reflection surface is composed of a transfer surface for compressing the reflection surface and a taper portion for forming the compression pressure transmitting portion. Mold for resin-made rotating polygon mirror. 6. A synthetic resin rotary polygonal mirror for injection compression molding a synthetic resin rotary polygonal mirror comprising a hole for fitting a rotary shaft, a plurality of reflecting surfaces formed on an outer peripheral surface, and a mounting reference surface. In the manufacturing equipment, a fixed die that molds the upper surface of the synthetic resin rotary polygon mirror, a mounting reference surface compression core that compresses the mounting reference surface of the synthetic resin rotary polygon mirror, and that can be controlled independently, and a synthetic resin rotation The reflecting surface of the polygon mirror is compressed, and the reflecting surface compression core that can be controlled independently and the reflecting surface of the rotary polygon mirror made of synthetic resin are transferred, and the compressing force is transmitted to the reflecting surface together with the reflecting surface compression core. A synthetic resin rotary polygon mirror manufacturing apparatus comprising: a mirror surface insert having a compression pressure transmitting portion for: 7. A synthetic resin rotary polygonal mirror for injection compression molding a synthetic resin rotary polygonal mirror comprising a hole for fitting a rotary shaft, a plurality of reflecting surfaces formed on an outer peripheral surface, and a mounting reference surface. In the manufacturing method, after injecting the thermoplastic synthetic resin into the molding die consisting of the fixed mold, the mirror surface insert, and at least two compression cores, the mounting reference surface of the synthetic resin rotary polygon mirror is formed by at least one compression core. At the same time as compressing, the reflecting surface of the synthetic resin rotary polygon mirror and the pressure transmitting portion of the mirror nest are placed outside the virtual extension line of the outline forming the reflecting surface or near the outside of the virtual extension line, and at least one other A method for manufacturing a rotary polygon mirror made of synthetic resin, characterized in that the outline of a compression core is arranged and compressed.