JP6074683B2 - Resin molding method - Google Patents

Description

The present invention relates to a tree butter molding how you suppress the occurrence of weld lines that occur in a portion in a mold of a resin molded the flow of the molten resin was fused joins.

  In resin molding, a weld line is generated at a location where the molten resin flows in the mold. If the meeting angle of the molten resin that joins is smaller than a certain angle, the weld line is noticeable and the appearance is poor. Further, when the weld line is generated, not only the appearance quality of the molded product is impaired, but also the strength of the molded product is lowered.

  For this reason, in Patent Document 1 and the like, a material having a different thermal conductivity is used for a specific shape portion of a molded product, and the molten resin is maintained at a high temperature so that a weld line is not generated around the specific shape portion. ing.

  FIG. 11 is a perspective view of a mold described in Patent Document 1. FIG. FIG. 12 is a top view of FIG. 11 and shows the behavior of the fluid resin. In the mold part (male) F shown in FIG. 11, a material having good thermal conductivity such as steel is used for the pin D used for forming the hole shape. It is inserted into the mold part F through the part E made of a material having poor thermal conductivity such as ceramic.

  As shown in FIG. 12, the fluid resin B around the pin D hits the pin D having good thermal conductivity, branches in two directions of the B1 direction and the B2 direction, and then merges again. When the pin D is inserted directly into the mold part F without using the part E made of a material having poor thermal conductivity, a weld line C indicated by an imaginary line is generated at the junction. Since Patent Document 1 uses a part E made of a material having poor thermal conductivity around the base end of the pin D, each of the flow resins branched in the B1 direction and the B2 direction has a lower temperature drop. Generation of the weld line C is prevented by reducing the decrease in the resin temperature by the heat-retaining action and setting the resin at the location where the resin passes through the pin D to join.

JP 2000-334743 A (FIGS. 1 and 2)

  However, since the method of Patent Document 1 can be applied only to molding of a molded product having a hole shape, the applicable range is largely limited to the shape of the molded product. In addition, the effect on the suppression of the weld line is limited.

The present invention solves the above-described conventional problems, and is not limited to the shape of a molded product, and can control the flow of resin, control the generation position of the weld line, and suppress the generation of the weld line. It aims to provide a method .

To achieve the above object, the resin molding method of the present invention, rotation of the molten resin into a cavity formed by the first mold and the second mold is injected, the molten resin was disposed on the inner surface of the cavity Rotating and compressing with a compression member, filling the cavity with the molten resin, stopping the rotation of the rotary compression member before the temperature of the molten resin drops to the glass transition point, and cooling the molten resin It is characterized by.

  According to the resin molding method and the resin molding die of the present invention, when the molten resin is injected into the cavity and filled, the flow of the molten resin is controlled by the operation of the rotary compression member, and so It is possible to control the weld line generated in step (1) and suppress the generation of the weld line without being limited by the shape of the molded product.

Sectional drawing of the molding die in Embodiment 1 of this invention Flow chart of molding method in the embodiment Plan view showing the behavior of resin in the cavity of the same embodiment Sectional drawing of the molding die in Embodiment 2 of this invention Flowchart of Example 1 in the same embodiment The top view which shows the behavior of resin in the cavity of Example 1 Flowchart of Example 2 in the same embodiment The top view which shows the behavior of resin in the cavity of Example 2 Flowchart of Example 3 in the same embodiment The top view which shows the behavior of the resin in the cavity of Example 3 The perspective view of the metal mold | die described in patent document 1 The top view of the principal part of FIG. 11 which shows the behavior of fluid resin

Hereinafter, embodiments of the present invention will be described with reference to the drawings.
(Embodiment 1)
1 to 3 show Embodiment 1 of the present invention.

FIG. 1 is a cross-sectional view of a molding die according to Embodiment 1 of the present invention.
The molding die 10 includes a first die 11 and a second die 12. The first and second molds 11 and 12 are made of steel. Reference numeral 13 denotes a cavity as a molding space formed in the molding die 10. The second mold 12 has a convex portion 12a for forming a window-shaped portion in the molded product.

  The molten resin 14 is injected into the cavity 13 via a sprue 15 formed by the first mold 11, a runner 16 formed by the second mold 12, and a gate 17 such as a side gate, for example.

  A rotary compression member 18 is disposed on the inner surface of the cavity 13. Specifically, on the extended line connecting the runner 16 and the gate 17 and on the rear side of the convex portion 12a when viewed from the gate 17, the second surface corresponding to the back surface on the non-visible side of the molded product formed by the cavity 13 is provided. The end face of the tip of the rotary compression member 18 is incorporated in the two molds 12 with the tip of the rotary compression member 18 exposed to the cavity 13. The end surface of the tip of the rotary compression member 18 is disposed so as to recede from the surface of the cavity 13, and a resin reservoir 18 a is formed. Further, the end surface of the tip of the rotary compression member 18 has a surface roughness that is rougher than the surface of the product part of the first and second molds 11 and 12.

  The rotary compression member 18 is made of a material such as bronze having higher thermal conductivity than the first and second molds 11 and 12. The rotational axis of the rotary compression member 18 coincides with the normal direction of the inner wall of the cavity 13.

  The outer peripheral surface of the rotary compression member 18 is supported by a cylindrical bearing hole formed in the second mold 12, and the rotary compression member 18 is driven to rotate about its own axis. Specifically, the rotary compression member 18 is rotationally driven by a motor via an axial direction conversion unit 19 that converts a rotational axis direction that is configured by a gear, and a rotation transmission unit 20 that is configured by a shaft. It is connected to the part 21. The rotary compression member 18 is configured to protrude in the direction of decreasing the volume of the cavity 13 in addition to being driven to rotate about its own axis. Specifically, the compression drive part 22 comprised with a hydraulic cylinder is connected with the rotary compression member 18 via the compression drive part 23 comprised with a joint structure. A control unit 24 controls the operation of the molding die 10.

FIG. 2 is a flowchart showing the configuration of the control unit 24. 3A to 3E show the behavior of the resin during molding.
In step S1, the first mold 11 and the second mold 12 are closed to form the cavity 13.

  In the subsequent step S2, as shown in FIG. 3A, the molten resin 14 is injected into the cavity 13 and the resin reservoir 18a via the sprue 15, the runner 16, and the gate 17. As shown in FIG. 3B, the molten resin 14 injected into the cavity 13 hits the convex portion 12a of the second mold 12 and branches in two directions, the molten resin 14a and the molten resin 14b. Then, as shown in FIG. 3C, the molten resins 14a and 14b merge as a molten resin 14c near the place where the resin reservoir 18a of the rotary compression member 18 is disposed.

  In step S3, the rotary compression member 18 is rotated in the direction D1 by the rotary drive unit 21 before the molten resin 14a and the molten resin 14b merge. Here, in the direction D1, the rotary compression member 18 is rotated clockwise around its own axis.

  In step S4, before the filling of the molten resin 14 into the cavity 13 is completed, the compression driving unit 22 projects the rotary compression member 18 in a direction to reduce the volume formed by the resin reservoir 18a and the cavity 13. Start the compression operation by starting the operation.

In step S5, the molten resin 14 is further filled into the cavity 13.
In step S6, the rotation of the rotary compression member 18 is stopped before the temperature of the molten resin 14c falls to the glass transition point.

  In step S7, the protrusion of the rotary compression member 18 that has started compression in step S4 is stopped before the temperature of the molten resin 14c drops to the glass transition point, and the compression state is maintained, and further pressurization is performed. Do not increase. The position of the end face at the front end of the rotary compression member 18 is a position that is retracted from the surface of the cavity 13 and the resin reservoir 18a remains without disappearing.

In step S8, the molding die 10 is cooled to cool the resin in the cavity 13.
In step S9, the first mold 11 and the second mold 12 are opened. In step S10, the molded product is taken out.

Note that the order of step S3 and step S4 may be reversed. The order of step S6 and step S7 may be reversed.
In this way, during the period from step S3 to step S7, the following processing is performed on the molten resin 14c injected into the cavity 13 by performing rotation and compression by the rotary compression member 18.

  Since the molten resin 14c joined to the upper portion of the rotary compression member 18 has viscosity, the rotation of the rotary compression member 18 causes the molten resin 14c to have a force in the direction D1 of the rotary compression member 18 shown in FIG. Join. Therefore, the traveling direction and traveling speed of the molten resin 14c can be changed. Further, the molten resin 14 c flows into the resin reservoir 18 a formed at the tip of the rotary compression member 18, so that the timing at which the molten resin 14 c fills the cavity 13 at the location of the rotary compression member 18 is delayed. As a result, the meeting angle of the resin in the portion of the rotary compression member 18 in FIG. 3D is reduced, and a weld line 25 is formed in the installation range of the rotary compression member 18 as shown in FIG. In step S4, the rotary compression member 18 is compressed and a compressive force is applied to the resin in the resin reservoir 18a, so that the resin around the weld line 25 is pressed against the surface of the first mold 11 serving as the appearance of the product. The occurrence of the weld line on the appearance surface of the molded product can be suppressed.

  As described above, by rotating the rotary compression member 18, the traveling direction and the traveling speed of the molten resin 14 c are changed, and when there is no rotary compression member 18, a weld line is considered to be formed at the point P. Generation of weld lines can be prevented.

  Further, since the molten resin 14c has viscosity, the resin compression heat is generated in the molten resin 14c by the rotation of the rotary compression member 18, and the molten resin 14c can be maintained at a high temperature. Therefore, there is an effect that the weld line is hardly formed. In addition, since the resin in the weld portion is kneaded, the strength of the weld portion can be improved.

  Further, since the rotary compression member 18 is formed of a material having higher thermal conductivity than the first and second molds 11 and 12, the resin shear heat generated in the rotary compression member 18 and the molten resin 14c is generated by the first and second molds 11 and 12. The second mold 11, 12 can be transmitted to the mold with higher efficiency. That is, it is possible to maintain the molding cycle of the molded product and cope with high-efficiency mass production molding even though the molten resin 14 becomes high temperature due to the resin shearing heat.

  Further, by making the surface roughness of the tip surface exposed to the cavity 13 of the rotary compression member 18 larger than the surface roughness of the surface of the cavity 13, the traveling direction and traveling speed of the molten resin 14c can be changed more effectively. Can do.

  Further, the rotary compression member 18 is disposed on the back side of the molded product other than the outer surface of the molded product, and the rotary compression member 18 is rotated with the axis of the rotary compression member 18 aligned with the normal direction of the molded product. By making it, it can prevent that the external appearance surface of a molded product gets a damage | wound.

  Moreover, since the part of the 2nd metal mold | die 12 which the rotation compression member 18 and the 2nd metal mold | die 12 contact is formed in the cylindrical shape, the smooth operation | movement in the rotation operation of a rotation compression member is attained. In addition, when the material of the rotary compression member 18 is a steel material, a nitriding treatment is applied to the cylindrical portion of the second mold 12 where the rotary compression member 18 and the second die 12 are in contact. In this case, the wear resistance of the rotary compression member 18 and the second mold 12 can be improved by performing a surface coating treatment such as chrome plating, Ti-N, PTFE or the like.

  In the present embodiment, bronze is used as the material of the rotary compression member 18, but instead, a high thermal conductivity component of another material, preferably aluminum alloy, brass, white bronze, or the like may be used.

  Furthermore, in the present embodiment, a motor is provided as the rotation drive unit 21, but instead, an air cylinder that can be used in a clean room, a fluid drive unit that uses the flow of cooling water in the mold, or the like is used. Also good.

In the present embodiment, a joint structure is provided as the compression transmission portion 23, but a cam structure or the like may be used instead.
Further, in the present embodiment, a hydraulic cylinder is provided as the compression drive unit 22, but instead, an air cylinder, a drive mechanism using a ball screw, a drive structure using a protruding mechanism of a molding machine, or the like is used. Also good.

  In this embodiment, a side gate is provided as a gate method, but instead, a gate of another method, a pin gate that does not require gate processing, a direct gate when used for a hot runner, or the like may be used. .

Furthermore, although one gate is provided in the present embodiment, a two-point gate or a multi-point gate may be used instead depending on the specifications of the molding die.
In this embodiment, the rotation stop timing of the rotary compression member 18 is set before the temperature of the molten resin falls to the glass transition point in order to prevent the occurrence of residual stress in the molded product. The stop timing of the compression member 18 may be set at the end of injection, the end of pressure holding, or before the completion of filling, where a stop signal can be picked up directly from the molding machine.

  In this embodiment, the compression stop timing of the rotary compression member 18 is set before the temperature of the molten resin 14 drops to the glass transition point after the rotation stop. Instead, the compression of the rotary compression member 18 is compressed. The stop timing may be set before the rotation stop, or at the end of injection, the end of holding pressure, or before completion of filling, where a stop signal can be picked up directly from the molding machine.

  Further, in the present embodiment, the position of the end face at the tip of the rotary compression member 18 stopped in step S7 is set back from the surface of the cavity 13, and the resin reservoir 18a remains without disappearing. However, instead, the position of the end face of the tip of the rotary compression member 18 stopped in step S7 is flush with the cavity 13, or the position of the end face of the tip of the rotary compression member 18 stopped in step S7 is the cavity 13. You may set to the state which protruded inside. The state in which the distal end of the rotary compression member 18 protrudes inside the cavity 13 is a state in which the distal end surface of the rotary compression member 18 is compressed to just before it comes into contact with the first mold 11.

  Further, in the present embodiment, the rotary compression member 18 is installed on the second mold 12 side. However, when the design surface of the external molded product is on the second mold 12 side, the external appearance required range of the molded product is within the required range. Accordingly, the rotary compression member 18 may be installed on the first mold 11 side.

(Embodiment 2)
4 to 10 show a second embodiment of the present invention.
In the case of the molding die 10 of the first embodiment, one gate 17 and one rotary compression member 18 are provided for the cavity 13, but in the molding die 10 of the second embodiment, FIG. As shown in FIG. 4, two gates 17A and 17B and two rotary compression members 18A and 18B are provided for the cavity 13. The rotary compression members 18A and 18B are arranged on the line connecting the gate 17A and the gate 17B with a space therebetween. Further, since the molded product does not have a window shape, the second mold 12 is not formed with the convex portion 12a seen in FIG.

  The molten resin 14d is injected into the cavity 13 via the sprue 15A, the runner 16A, and the gate 17A. The molten resin 14e is injected into the cavity 13 via the sprue 15B, the runner 16B, and the gate 17B.

  The end face of the tip of the rotary compression member 18A is incorporated in a state of being retracted from the surface of the cavity 13, and a concave resin reservoir 18a is formed. The rotary compression member 18 is connected to a rotation drive unit 21A configured by a motor via an axial direction conversion unit 19A that converts a rotation axis direction configured by a gear and a rotation transmission unit 20A configured by a shaft. ing. Further, the rotary compression member 18A is configured to protrude in the direction of decreasing the volume of the cavity 13 in addition to being driven to rotate about its own axis. Specifically, a compression drive unit 22A configured with a hydraulic cylinder is coupled to the rotary compression member 18A via a compression drive unit 23A configured with a joint structure.

  The end face of the tip of the rotary compression member 18B is incorporated in a state of being retracted from the surface of the cavity 13, and a concave resin reservoir 18a is formed. The rotary compression member 18B is coupled to a rotation drive unit 21B configured by a motor via an axial direction conversion unit 19B that converts a rotation axis direction configured by a gear and a rotation transmission unit 20B configured by a shaft. ing. Further, the rotary compression member 18B is configured to protrude in the direction of decreasing the volume of the cavity 13 in addition to being driven to rotate about its own axis. Specifically, the compression drive part 22B comprised with a hydraulic cylinder is connected with the rotary compression member 18B via the compression drive part 23B comprised with a joint structure.

A control unit 26 controls the operation of the molding die 10. Other configurations are the same as those of the first embodiment.
Example 1
FIG. 5 is a flowchart showing the configuration of the control unit 26.

6A to 6E show the behavior of the resin during molding. Here, a case where the rotary compression members 18A and 18B are rotated in the same direction, for example, the clockwise D1 direction is shown.
In step S1, the first mold 11 and the second mold 12 are closed.

  In subsequent steps S2 and S3, as shown in FIGS. 6A, 6B, and 6C, the molten resin 14d is injected into the cavity 13 through the sprue 15A, the runner 16A, and the gate 17A. At the same time, the molten resin 14e is injected into the cavity 13 via the sprue 15B, the runner 16B, and the gate 17B. Further, the rotary compression members 18A and 18B are rotated at the same speed in the clockwise direction D1.

  In step S4 in the state of FIG. 6E, the rotary compression members 18A and 18B are replaced by the volume of the cavity 13 by the compression drive units 22A and 22B before the cavity 13 is completely filled with the molten resins 14d and 14e. It projects in the direction of decreasing the pressure and is compressed.

In step S5, the molten resin 14d, 14e is further filled into the cavity 13.
In step S6, the rotation of the rotary compression members 18A and 18B is stopped before the temperature of the molten resins 14d and 14e drops to the glass transition point.

In step S7, before the temperature of the molten resin 14c falls to the glass transition point, the extrusion of the rotary compression members 18A and 18B is stopped, and the compression operation at that time is held.
In step S8, the molding die 10 is cooled to cool the resin in the cavity 13.
In step S9, the first mold 11 and the second mold 12 are opened. In step S10, the molded product is taken out.

Note that the order of step S3 and step S4 may be reversed. The order of step S6 and step S7 may be reversed.
Since the molten resin 14d and the molten resin 14e have viscosity, as shown in FIGS. 6B and 6C, the rotation of the rotary compression members 18A and 18B causes each of the molten resins 14c and 14d to move in the rotation direction D1. Power is added. Therefore, the traveling direction and the traveling speed of the molten resins 14d and 14e can be changed. Further, the molten resins 14d and 14e flow into the resin reservoirs 18a and 18a formed at the tips of the rotary compression members 18A and 18B, so that the molten resins 14d and 14e enter the cavity 13 at the locations of the rotary compression members 18A and 18B. The filling timing is delayed.

  Thereby, the association angle of the resin in the portions of the rotary compression members 18A and 18B in FIG. 6D is increased, and as shown in FIG. 6E, weld lines 25a, 25a, 25b, and 25b are formed. Since the weld lines 25a and 25a are both formed in the installation range of the rotary compression members 18A and 18B, the rotary compression members 18A and 18B are compressed to apply a compression force to the resin in the respective resin reservoirs 18a and 18a. As a result, the resin around the weld lines 25a, 25a is pressed against the surface of the first mold 11 which is the appearance surface of the molded product, and the occurrence of a weld line at the center that is conspicuous as the appearance surface of the molded product is suppressed.

  As described above, by rotating the rotary compression members 18A and 18B in the same direction, the traveling direction and the traveling speed of the molten resin 14d and the molten resin 14e can be changed, and when there is no rotary compression member 18, a weld line is formed. It is possible to prevent the occurrence of a weld line at the point P that is considered to be generated.

  In addition, by moving the generation location to the weld lines 25a and 25a, the compression operation of the rotary compression member 18 can suppress the generation of a weld line at the center that is conspicuous as the appearance surface of the molded product.

  Although the rotation operation and the compression operation of the rotary compression members 18A and 18B are performed at the same time, the rotary compression members 18A and 18B may be set to rotate and compress at different timings.

  Further, although the compression amount of the rotary compression members 18A and 18B and the volume of the resin reservoir 18a of the rotary compression member 18A are the same as the volume of the resin reservoir 18a of the rotary compression member 18B, the compression amount of the rotary compression member 18A When the compression amount of the rotary compression member 18B is different, the volume of the resin reservoir 18a of the rotary compression member 18A and the volume of the resin reservoir 18a of the rotary compression member 18B may be set to be different. Thereby, the generation | occurrence | production position of the weld lines 25a and 25a can be finely adjusted.

Example 2
In step S3 shown in FIG. 5, the rotary compression members 18A and 18B are rotated in the same direction, but the behavior of the resin during molding when the rotary compression members 18A and 18B are rotated in the opposite directions is shown in FIG. Different from (a) to (e). Others are the same as in the embodiment of FIG.

FIG. 7 is a flowchart showing the configuration of the control unit 26 when the rotary compression members 18A and 18B are rotated in opposite directions. The behavior of the resin during molding in this case is shown in FIG.
8A to 8E, the rotary compression member 18A is rotated in the clockwise D1 direction, and the rotary compression member 18B is rotated in the counterclockwise D2 direction. The rotational speeds of the rotary compression members 18A and 18B are the same.

  Specifically, after the first mold 11 and the second mold 12 are closed, in step S2, as shown in FIG. 8A, molten resins 14d and 14e are injected into the cavity 13, and step S3. When the rotary compression members 18A and 18B are rotated in the opposite direction, the molten resins 14d and 14e have viscosity. Therefore, as shown in FIG. 8B, the rotation of the rotary compression members 18A and 18B causes the molten resin 14d to rotate. The force in the direction D1 of the rotary compression member 18A is applied. A force in the direction D2 of the rotary compression member 18B is applied to the molten resin 14e. Therefore, the advancing direction and advancing speed of the molten resins 14d and 14e are changed, and the molten resins 14d and 14e merge between the rotary compression members 18A and 18B as shown in FIG. Resin joins at the place P shown in 8 (d). Then, weld lines 25a, 25a, and 25b are formed at the locations shown in FIG. The weld lines 25a and 25a are formed in the installation range of the rotary compression member 18A and the rotary compression member 18B. In step S4, the rotary compression members 18A and 18B are compressed and a compressive force is applied to the resin in the resin reservoirs 18a and 18a, whereby the resin around the weld lines 25a and 25a becomes the first appearance surface of the molded product. Generation of a weld line in the central portion that is pressed against the surface of the mold 11 and is conspicuous as an appearance surface of the molded product can be suppressed.

Example 3
FIG. 9 is a flowchart showing the configuration of the control unit 26 when the rotary compression members 18A and 18B are rotated in opposite directions and the rotational speeds of the two are different. The behavior of the resin during molding in this case is shown in FIG. Others are the same as in the embodiment of FIG.

  10A to 10E, in step S3, the rotary compression member 18A is rotated in the clockwise direction D1, the rotary compression member 18B is rotated in the counterclockwise direction D2, and the rotary compression member 18A is rotated. The behavior of the resin during molding when the rotational speed of the rotary compression member 18B is fast is shown.

  Since the molten resin 14d and the molten resin 14e have viscosity, as shown in FIG. 10B, the rotation of the rotary compression member 18A and the rotary compression member 18B causes the molten resin 14d to move in the direction D1 of the rotary compression member 18A. The force of rotation is added. A rotational force in the direction D2 of the rotary compression member 18B is applied to the molten resin 14e. Further, since the rotational speed of the rotary compression member 18B is faster than that of the rotary compression member 18A, the traveling direction and traveling speed of the molten resin 14e are greatly changed from those of the molten resin 14d, and the state shown in FIG. The molten resin 14d, 14e finally joins the place shown in FIG.

  After completing the filling of the resin into the cavity 13, weld lines 25a, 25a, and 25b are formed at the locations shown in FIG. Since the weld lines 25a and 25a are formed in the installation range of the rotary compression members 18A and 18B, in step S4, the rotary compression members 18A and 18B are compressed to apply a compression force to the resin in the resin reservoirs 18a and 18a. In addition, the resin around the weld lines 25a, 25a is pressed against the surface of the first mold 11 which is the appearance surface of the molded product, and the occurrence of a weld line at the center that is conspicuous as the appearance surface of the molded product can be suppressed. Further, the generation position of the weld line 25b can be arbitrarily controlled by controlling the rotation speed of the rotary compression members 18A and 18B.

  The present invention can be applied to the molding of resin molded products of casings of various apparatuses such as a casing of a mobile phone device or a casing of a notebook computer.

DESCRIPTION OF SYMBOLS 10 Molding die 11 1st metal mold | die 12 2nd metal mold | die 12a Protrusion part 13 Cavity 14 Molten resin 15 Sprue 16 Runner 17 Gate 18, 18A, 18B Rotary compression member 18a Resin reservoir part 19 Axial direction conversion part 20 Rotation transmission part 21 Rotation drive unit 22 Compression drive unit 23 Compression drive unit 24, 26 Control unit 25a, 25b Weld line D1 Rotation direction of rotation compression member (clockwise direction)
D2 Rotation direction of the rotary compression member (counterclockwise direction)

Claims (8)

Injecting molten resin into the cavity formed by the first mold and the second mold,
The molten resin is rotated and compressed by a rotary compression member disposed on the inner surface of the cavity,
Filling the cavity with the molten resin;
It said rotation of said rotary compression element, the stop before the temperature of the molten resin drops glass transition temperature, cooling the molten resin,
Resin molding method. The rotary compression member is
Disposing at least first and second rotary compression members on the inner surface of the cavity, and rotating both the first and second rotary compression members in the same direction;
The resin molding method according to claim 1 . The rotary compression member is
Disposing at least first and second rotary compression members on the inner surface of the cavity and rotating the first and second rotary compression members in opposite directions;
The resin molding method according to claim 1 . The rotational speeds of the first and second rotary compression members are different from each other;
The resin molding method according to claim 2 or 3 . The compression amounts of the first and second rotary compression members are different from each other;
The resin molding method according to claim 2 . The rotary compression member is stopped before the temperature of the molten resin falls to the glass transition point,
The resin molding method according to claim 1 . Rotating and compressing the rotary compression member on the non-visible side of the appearance molded article,
The resin molding method according to claim 1 . The rotary compression member is rotated with the normal line of the surface of the molded product corresponding to the position where the rotary compression member is disposed as a rotation axis.
The resin molding method according to claim 1 .

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