JP6214592B2 - Mold for resin molding - Google Patents

Description

  The present invention relates to a resin mold.

In a resin molded product, a weld line may occur at or near a point where the resin joins during injection molding.
In particular, in a resin molded product having a through hole, a weld line is generated in the vicinity of the through hole. Since the resin flows around the core that penetrates the cavity of the resin molding die and the resin joins on the back side of the core, a weld line is generated.
This weld line has a problem that the appearance design of the resin molded product is damaged, or the strength of the resin molded product is reduced.

Therefore, in the molding apparatus and the molding method disclosed in Patent Document 1, a runner gate (spool) is connected to a portion that becomes a through hole (discard portion), is filled with resin, and a portion that becomes a through hole after molding is cut off. I have to.
According to this molding apparatus and molding method, since there is no core that penetrates the cavity of the resin molding die, it is possible to prevent a weld line from being generated in the vicinity of the through hole.

Japanese Patent Application Laid-Open No. 2014-166689

  However, in the above-described molding apparatus and molding method, there is a problem that the shape of the resin molding die becomes complicated when there are a plurality of portions (discarding portions) that become through holes. That is, if a runner gate is connected to each portion to be a through hole, the resin molding die becomes complicated, resulting in an increase in manufacturing cost.

Further, in the above-described molding apparatus and molding method, the outer peripheral portion of the portion serving as the through hole is formed thin (thin) so that the portion serving as the through hole can be cut off.
For this reason, at the time of injection molding, there is a problem that the resin flows around the outer peripheral portion of the portion that becomes the through hole and a weld line is generated.

  An object of the present invention is to provide a mold for resin molding that can reliably prevent generation of a weld line around a through hole when molding a resin molded product having a through hole.

A first embodiment of a resin molding die according to the present invention is a resin molding die for molding a resin molded product having a through hole, and the portion that becomes the through hole is made a cavity before resin injection. A movable core that is disposed at a position and moves to a molding position that fills the cavity after resin injection , and the movable core has a projecting portion that protrudes in an annular shape at the periphery of the distal end surface. The recess excluding the portion has the same depth as the surrounding cavity forming the periphery of the through hole .

  In a second embodiment of the resin molding die according to the present invention, in the first embodiment, the molding position is such that the movable core is close to a molding surface that is flush with a molding surface that forms the periphery of the through hole. Or it is the position which contact | abuts, It is characterized by the above-mentioned.

According to a third embodiment of the resin molding die according to the present invention, in the first or second embodiment , when a plurality of the through holes are formed in the resin molded product, the distance to each of the through holes is The gate is arranged at a position where the sum is minimized.

According to a fourth embodiment of the resin mold according to the present invention, in any one of the first to third embodiments, the through hole is a fitting hole into which a decorative member molded with resin is inserted. And

In the resin molding die and the resin molding method according to the present invention, the movable core for molding the through hole is disposed at a retreat position where the portion that becomes the through hole at the time of resin injection is hollow. For this reason, resin does not flow around the movable core, and the resin does not merge on the back side of the movable core. Therefore, no weld line is generated around the through hole.
Therefore, the designability of the resin molded product can be improved.

Moreover, since the movable core moves to a molding position for filling the cavity (portion serving as the through hole) after the resin is injected, the through hole can be reliably molded.
In particular, when the movable core moves to the molding position, it approaches or abuts the molding surface that is flush with the molding surface that molds the periphery of the through hole. The resin placed in is not completely separated. For this reason, the resin disposed in the portion serving as the through hole does not remain in the resin molding die, and it is not necessary to provide a device for removing the resin or the like in the resin molding die.
On the other hand, the resin disposed in the portion serving as the through hole and the resin disposed around the through hole are connected through the thin portion. For this reason, after taking out the resin molded product from the mold for resin molding, the resin arranged in the portion serving as the through hole can be easily removed by pressing the resin disposed in the portion serving as the through hole.

It is a figure which shows the mounting goods 1 for vehicles which concern on embodiment of this invention, Comprising: (a) Top view, (b) Ib-Ib sectional drawing. It is a figure which shows the colored member 10 which concerns on embodiment of this invention, Comprising: (a) Top view, (b) IIb-IIb sectional drawing. It is a figure which shows the structure of the metal mold | die 20 for resin molding which concerns on embodiment of this invention. It is a figure which shows the resin molding method which concerns on embodiment of this invention, Comprising: (a) Retraction | saving process, (b) Resin injection | pouring process, (c) Molding process is shown. It is a figure which shows the colored member 10 immediately after shaping | molding, Comprising: It is (a) top view, (b) Vb-Vb sectional drawing, (c) It is a principal part enlarged view. It is a figure which shows the process of removing the discard site | part 11, Comprising: (a) Before removal, (b) After removal is shown.

Hereinafter, a resin molding die and a resin molding method according to an embodiment of the present invention will be described with reference to the drawings.
In each drawing used for the following description, the scale of each member is appropriately changed in order to make each member a recognizable size.

<Resin molded product: colored member 10>
1A and 1B are diagrams showing a vehicle mounted product 1, which are (a) a plan view and (b) a cross-sectional view taken along Ib-Ib.
2A and 2B are diagrams showing the colored member 10 and are (a) a plan view and (b) a sectional view taken along IIb-IIb.

  The thickness direction of the colored member 10 (vehicle mounting product 1) is referred to as the front-rear direction. The dividing direction of the resin molding die 20 (the thickness direction of the colored member 10) is referred to as the vertical direction.

The vehicle mounting product 1 is a resin molded product mounted on the vehicle A and is exposed on the front surface of the vehicle A.
The vehicle mounted product 1 includes a metal glittering member 5 that exhibits metal glitter and a colored member 10 that exhibits a color such as black.

The metallic glittering member (decorative member) 5 is a band-shaped member extending along the horizontal direction. The metallic glitter member 5 represents an emblem M that is a mark of the vehicle A.
The metallic glitter member 5 is made of a synthetic resin such as ABS (acrylonitrile / butadiene / styrene copolymer synthetic resin), PC or PET (polyethylene terephthalate).
On the front surface of the metallic glitter member 5, a metal layer formed by using a metal vapor deposition process, and a base coat layer and a top coat layer (both not shown) for protecting the metal layer are disposed.
A pair of circular fitting shafts 6 are formed on the rear surface of the metallic glitter member 5 so as to protrude.

The colored member (resin molded product) 10 is provided in a region around the metallic glitter member 5 so as to surround the metallic glitter member 5. The colored member 10 is in close contact with the rear surface of the metallic glitter member 5 and holds the metallic glitter member 5.
The colored member 10 is made of synthetic resin such as ABS, AES (acrylonitrile / ethylene / styrene copolymer synthetic resin), PBT (polybutylene terephthalate), PC, PET, or a composite resin thereof.

The colored member 10 is formed into a thin plate shape that is slightly curved. The colored member 10 is formed to a thickness of about 2.0 mm to 10 mm, for example.
A pair of circular through holes 12 that penetrates in the thickness direction is formed in the central portion of the colored member 10. A pair of fitting shafts 6 of the metallic glitter member 5 are fitted into the pair of through holes (fitting holes) 12, respectively. That is, the metallic glitter member 5 is fixed to the colored member 10 by fitting the fitting shaft 6 into the through hole 12.

<Mold 20 for resin molding>
FIG. 3 is a diagram showing a configuration of the resin molding die 20 according to the embodiment of the present invention.
The resin molding die 20 is a die used in an injection molding machine (not shown) and is called a so-called three-plate die.

The resin molding die 20 includes a nest 21 having a cavity C for molding the colored member 10. The insert 21 includes an upper mold 22 called a cavity and a lower mold 24 called a core, and a cavity (peripheral cavity) C filled with molten resin is formed between the upper mold 22 and the lower mold 24.
Two cavities C are formed in the resin molding die 20. That is, the two colored members 10 are molded by a single resin molding.
The cavity C is formed by the molding surface 22s of the upper mold 22 and the molding surface 24s of the lower mold 24. The molding surface 22s of the upper mold 22 is a surface that molds the front surface of the colored member 10, and is formed to be slightly concavely curved. The molding surface 24s of the lower mold 24 is a surface for molding the rear surface of the colored member 10, and is formed to be slightly convexly curved.

  The resin molding die 20 includes a fixed side mold plate 30, a runner stripper plate 31, a fixed side mounting plate 32, a spool bush 33, a runner lock pin 34, a runner 35, and the like on the fixed side that holds the upper die 22.

  The resin molding die 20 includes a movable side mold plate 36, an ejector plate upper 37, an ejector plate lower 38, a movable side mounting plate 39, a return pin 40, a return spring 41, a return on the movable side that holds the lower mold 24. A guide 42, an ejector pin 43, an ejector stopper 44, an ejector block 45, and the like are provided.

The resin molding die 20 includes a movable core 26 that molds the through hole 12 of the colored member 10. The movable core 26 is a member constituting a part of the lower mold 24 and is formed in an elongated cylindrical shape.
The movable core 26 can slide relative to the lower mold 24 to open or fill a part of the cavity C. That is, the part (cavity Ch) used as the through-hole 12 among the cavity C is vacated or filled.
The base end (lower end) of the movable core 26 is held and fixed to the upper ejector plate 37 and the lower ejector plate 38. Thereby, the movable core 26 can move in the vertical direction.

Specifically, the movable core 26 moves to a retreat position P1 in which a portion that becomes the through hole 12 is a cavity Ch and a molding position P2 in which the cavity Ch is filled.
At the retracted position P1, the distal end surface 27 of the movable core 26 is substantially flush with the molding surface 24s of the lower mold 24. On the other hand, at the molding position P2, the tip surface 27 of the movable core 26 contacts the molding surface 22s (hole molding surface 22t) of the upper mold 22.

Of the molding surface 22 s of the upper mold 22, the hole molding surface 22 t with which the distal end surface 27 of the movable core 26 abuts is formed flush with the molding surface 22 s that molds the portion around the through hole 12. That is, the hole forming surface 22t is formed integrally with the surrounding forming surface 22s without any step.
For this reason, the movable core 26 comes into contact with the hole forming surface 22t of the upper mold 22 and is flush with the forming surface 22s (disposed on the same surface) at the forming position P2.

An annular protrusion 28 whose peripheral edge protrudes upward is formed on the distal end surface 27 of the movable core 26. The protrusion 28 is formed at an acute angle by digging out all the regions except the peripheral edge. In other words, in the tip surface 27 excluding the peripheral edge (projecting portion 28), a recessed portion 29 that is recessed downward is formed. The depth (length in the vertical direction) of the recess 29 is set to be substantially the same as the thickness of the cavity C.
For this reason, when the protrusion 28 of the movable core 26 contacts the hole forming surface 22t of the upper mold 22 at the molding position P2, the recess 29 is substantially flush with the molding surface 24s of the lower mold 24. That is, the thickness of the cavity Ch in the portion that becomes the through hole 12 is substantially the same as the thickness of the cavity C.
At the retracted position P1, the protrusion 28 of the movable core 26 is substantially flush with the molding surface 24s of the lower mold 24. That is, the thickness of the cavity Ch in the portion that becomes the through hole 12 is almost twice the thickness of the cavity C.

<Resin molding method>
FIG. 4 is a diagram showing a resin molding method according to an embodiment of the present invention, and shows (a) a evacuation process, (b) a resin injection process, and (c) a molding process.
The manufacturing process for resin molding the colored member 10 includes a retreat process, a resin injection process, a molding process, and a removal process.
In the evacuation step, the movable core 26 that forms the portion that becomes the through-hole 12 is moved to make the portion that becomes the through-hole 12 a cavity Ch. In the resin injection step, resin is injected into the cavities C and Ch. In the molding process, the movable core 26 is moved to fill the cavity Ch. In the removing step, the resin disposed in the cavity Ch is removed after the resin is cured.
Hereinafter, these steps will be described in detail.

First, in the retracting process (before resin injection), as shown in FIG. 4A, the upper mold 22 and the lower mold 24 of the resin molding die 20 are brought into close contact with each other so that the cavity C appears.
Then, the movable core 26 is moved downward to place the movable core 26 at the retracted position P1. By bringing the upper ejector plate 37 and the lower ejector plate 38 into close contact with the movable mounting plate 39, the movable core 26 can be disposed at the retracted position P1.
As described above, at the retracted position P1, the protrusion 28 of the movable core 26 is substantially flush with the molding surface 24s of the lower mold 24. For this reason, the thickness of the cavity Ch in the portion that becomes the through hole 12 is almost twice the thickness of the cavity C.

Next, in the resin injection step, as shown in FIG. 4B, the cavities C and Ch of the resin molding die 20 are filled with molten resin.
At this time, the movable core 26 is not disposed in the portion to be the through hole 12, and a cavity Ch communicating with the cavity C is formed. For this reason, the molten resin is smoothly filled in the cavities C and Ch without branching or merging. That is, there is no branching or merging of the molten resin that causes the weld line.

Subsequently, a molding step (after resin injection) is performed before the molten resin is cured. That is, in the molding step, as shown in FIG. 4C, the movable core 26 is moved upward, and the movable core 26 is disposed at the molding position P2. The movable core 26 can be disposed at the molding position P2 by moving the upper ejector plate 37 and the lower ejector plate 38 upward by the thickness of the cavity C.
As described above, the protrusion 28 of the movable core 26 contacts the hole forming surface 22t of the upper mold 22 at the forming position P2. For this reason, the thickness of the cavity Ch in the portion that becomes the through hole 12 is substantially the same as the thickness of the cavity C. That is, when the resin injection process shifts to the molding process, the volume of the cavity C is almost halved.
Therefore, about half of the molten resin filled in the cavity Ch in the resin injection process is pushed out of the cavity Ch into the cavity C.
Thereafter, the resin molding die 20 is cooled to cure the molten resin filled in the cavities C and Ch.

Next, when the resin is cured, the upper mold 22 and the lower mold 24 of the resin molding die 20 are separated, and the colored member 10 is taken out from the cavity C. Then, the resin (disposal part 11) molded in the portion that becomes the through hole 12 is removed from the colored member 10 immediately after molding. A method for removing the disposal site 11 will be described later.
The colored member 10 is manufactured through such steps.

FIGS. 5A and 5B are diagrams showing the colored member 10 immediately after molding, in which FIG. 5A is a plan view, FIG. 5B is a Vb-Vb cross-sectional view, and FIG.
FIG. 6 is a diagram showing a step (removal step) for removing the disposal site 11, and shows (a) before removal and (b) after removal.

As shown in FIG. 5, the colored member 10 immediately after molding has a disposal site 11 in a portion that becomes the through hole 12. The disposal site 11 has a disk shape smaller in diameter than the through hole 12 and is formed concentrically with the through hole 12. The thickness of the disposal part 11 is substantially the same as the thickness of the part around the through hole 12.
Further, the disposal site 11 is connected to the colored member 10 via the thin portion 13. The thin portion 13 is formed in an annular shape along the inner periphery of the through hole 12 and the outer periphery of the disposal site 11. The thin-walled portion 13 does not completely connect the colored member 10 and the disposal site 11 but may be molded in a state where a part thereof is cut (damaged).

The disposal site 11 is a material obtained by curing the molten resin remaining in the cavity Ch in the molding step described above.
The thin portion 13 is obtained by curing the molten resin remaining between the projection 28 of the movable core 26 and the hole forming surface 22t of the upper mold 22 in the molding process. Although the protrusion 28 and the hole forming surface 22t are in close contact with each other in the molding process, a slight amount of molten resin remains between the protrusion 28 and the hole forming surface 22t. For this reason, the thin part 13 is shape | molded between the site | part around the through-hole 12, and the discard site | part 11 in the colored member 10 immediately after shaping | molding.

  As described above, of the molding surface 22 s of the upper mold 22, the hole molding surface 22 t with which the tip surface 27 of the movable core 26 abuts is formed flush with the molding surface 22 s that molds a portion around the through hole 12. The For this reason, since the site | part around the thin part 13 and the through-hole 12 does not have a level | step difference, it shape | molds integrally, without dividing. That is, the thin portion 13 and the portion around the through hole 12 are formed in a connected state.

Since the thin-walled portion 13 is molded with a small amount of resin, it is easily damaged. Immediately after the molding, the portion around the thin portion 13 and the through hole 12 may not be completely connected and may be molded in a partially damaged state. That is, the thin portion 13 is formed so as to be easily cut by applying a slight force.
For this reason, as shown in FIG. 6, the thin portion 13 is broken only by lightly pressing the discard site 11 with a finger or the like, and the discard site 11 is separated and removed from the colored member 10.
Thus, the through hole 12 is formed (appears) in the colored member 10.

Further, as shown in FIG. 5, the colored member 10 has a gate 15 at substantially the center of the colored member 10 immediately after molding.
The gate 15 is an inflow passage through which molten resin injected from a nozzle of an injection molding machine (not shown) flows into the cavity C to be the colored member 10 in the resin molding die 20 for molding the colored member 10.

The gate 15 is disposed substantially at the center of the colored member 10. More precisely, the gate 15 is disposed at an intermediate position between the pair of through holes 12. The gate 15 is disposed at a position where the sum of the distances from the respective through holes 12 is minimized. That is, the gate 15 is disposed at the center of gravity of the plurality of through holes 12.
For this reason, when molten resin is injected into the cavity C of the resin molding die 20 (resin injection step), the molten resin is filled into the cavity Ch of the portion to be the through hole 12 in the shortest time. In the colored member 10, the two cavities Ch are filled with molten resin almost simultaneously. Therefore, the plurality of movable cores 26 can be simultaneously moved to the molding position P2 without providing a time difference. That is, the resin molding die 20 and the molding process are not complicated, and the manufacturing cost and the efficiency of the manufacturing process can be improved.
The gate 15 is covered with the metal glitter member 5. For this reason, when the vehicle mounting product 1 (colored member 10) is viewed from the front, the design of the emblem M is not impaired.

As described above, the resin molding die 20 according to this embodiment includes the movable core 26. The movable core 26 is disposed at a retreat position P1 where the portion to be the through hole 12 is made a cavity Ch before pouring the molten resin, and moves to a molding position P2 where the cavity Ch is filled after the molten resin is injected.
For this reason, at the time of resin injection, the movable core 26 is not disposed in the portion that becomes the through hole 12, and a cavity Ch that communicates with the cavity C is formed. Therefore, the whole of the cavities C and Ch is smoothly filled without the flow of the molten resin branching or joining.
Therefore, it is possible to prevent a weld line from being generated around the through hole 12 of the colored member 10.

Further, the molding position P2 is a position where the movable core 26 comes close to or abuts the hole molding surface 22t that is flush with the molding surface 22s that molds the periphery of the through hole 12. For this reason, the molten resin remaining between the protrusion 28 of the movable core 26 and the hole forming surface 22t of the upper mold 22 is cured, and the thin portion 13 is formed. That is, the thin portion 13 and the portion around the through hole 12 are formed in a connected state.
Therefore, the resin filled in the cavity Ch of the portion that becomes the through hole 12 can be taken out from the resin molding die 20 integrally with the colored member 10 without remaining in the resin molding die 20. it can.
Therefore, it is not necessary to provide a device for removing excess resin (discarded portion 11) in the resin molding die 20, and the resin molding die 20 can be prevented from being complicated and reduced in cost.

The movable core 26 has a protrusion 28 that protrudes in an annular shape on the periphery of the tip surface 27. For this reason, the thin part 13 can be reliably shape | molded between the part (discarding part 11) used as the through-hole 12, and the through-hole 12. FIG.
Further, in the tip surface 27, the recess 29 excluding the protrusion 28 has the same depth as the cavity C that forms the periphery of the through hole 12. For this reason, the cooling rates of the molten resin filled in the cavity C and the cavity Ch are substantially the same. Therefore, the disposal site 11 and the colored member 10 are molded almost simultaneously, and the production efficiency is improved.

Further, when a plurality of through holes 12 are formed in the colored member 10, the gate 15 is disposed at a position where the sum of the distances to the through holes 12 is minimized.
For this reason, when the molten resin is injected into the cavity C of the resin molding die 20, the molten resin is filled in the cavity Ch of the portion to be the through hole 12 in the shortest time. Therefore, the plurality of movable cores 26 can be simultaneously moved to the molding position P2 without providing a time difference.
Therefore, the resin molding die 20 and the molding process are not complicated, and the manufacturing cost and the efficiency of the manufacturing process can be improved.

  The fitting shaft 6 of the metallic glitter member 5 is fitted in the through hole 12 of the colored member 10. Thereby, the metallic luster member 5 can be reliably fixed to the colored member 10. Since there is no weld line around the through hole 12, the design of the emblem M made of the metallic glitter member 5 is not impaired.

In addition, the resin molding method according to the present embodiment includes a retreat process, a resin injection process, a molding process, and a removal process.
In the evacuation step, the movable core 26 for forming the portion that becomes the through-hole 12 (discarding portion 11) is moved to make the portion that becomes the through-hole 12 a cavity Ch. In the resin injection step, resin is injected into the cavities C and Ch. In the molding process, the movable core 26 is moved to fill the cavity Ch. In the removing step, the resin (discarded portion 11) disposed in the cavity Ch after the resin is cured is removed.
For this reason, in the resin injecting step, the movable core 26 is not disposed in the portion that becomes the through hole 12, and a cavity Ch that communicates with the cavity C is formed. Therefore, the whole of the cavities C and Ch is smoothly filled without the flow of the molten resin branching or joining.
Therefore, it is possible to prevent a weld line from being generated around the through hole 12 of the colored member 10.

Further, since the movable core 26 is brought close to or in contact with the hole forming surface 22t that is flush with the forming surface 22s that forms the periphery of the through hole 12, the disposal region 11 and the region around the through hole 12 (the colored member 10) A thin portion 13 is formed therebetween. Therefore, the resin filled in the cavity Ch of the portion that becomes the through hole 12 can be taken out from the resin molding die 20 integrally with the colored member 10 without remaining in the resin molding die 20. it can.
Therefore, complication of the resin molding method can be prevented.

  Further, in the removing step, after the colored member 10 is taken out from the resin molding die 20, the resin (discarded portion 11) disposed in the portion (hollow Ch) that becomes the through hole 12 is pressed and removed. Therefore, the through hole 12 can be easily and reliably formed.

Thus, in the resin molding die 20 and the resin molding method according to the present invention, the molten resin does not flow around the movable core 26 and the resin does not merge on the back side of the movable core 26. Therefore, no weld line is generated around the through hole 12.
Therefore, the designability of the resin molded product can be improved.

Moreover, since the movable core 26 moves to the molding position P2 that fills the cavity Ch after the resin injection, the through-hole 12 can be reliably molded.
In particular, when the movable core 26 moves to the molding position P2, the movable core 26 is close to or in contact with the molding surface 22t that is the same as the molding surface 22s that molds the periphery of the through-hole 12, so that the movable core 26 is disposed in the portion that becomes the through-hole 12. The resin and the resin disposed around the through hole 12 are not completely separated. For this reason, the resin arranged in the portion that becomes the through hole 12 does not remain inside the resin molding die 20, and it is not necessary to provide an apparatus or the like for removing the resin in the resin molding die.
On the other hand, the resin disposed in the portion that becomes the through hole 12 and the resin disposed around the through hole 12 are connected via the thin portion 13. For this reason, after taking out the colored member 10 from the resin molding die 20, the resin disposed in the portion that becomes the through hole 12 is easily removed by pressing the resin disposed in the portion that becomes the through hole 12. it can.

  Various shapes, combinations, and the like of the constituent members shown in the above-described embodiments are merely examples, and various modifications can be made based on design requirements and the like without departing from the gist of the present invention.

The number of through holes 12 is not limited to two, but may be one or three or more.
The through-hole 12 is not limited to a circle but may be a rectangle or the like. It may be a case where a plurality of through holes having different shapes are provided.
The through hole 12 is not limited to a fitting hole into which a decorative member such as the metallic glittering member 5 is inserted, and may be a vent hole or a through hole.

  The resin molded product is not limited to the colored member 10 such as black, but may be a transparent member, for example. Further, the resin molded product may be two-color molded or insert molded.

  The molding position P <b> 2 is not limited to the case where the protruding portion 28 of the movable core 26 contacts the hole molding surface 22 t of the upper mold 22. The forming position P2 may be a case where the protrusion 28 is close to the hole forming surface 22t and a slight gap is formed. Even in this case, the thin part 13 thinner than these can be formed between the colored member 10 and the disposal part 11.

The protrusion 28 is not limited to the ring shape along the periphery of the tip surface 27. That is, it is not limited to a complete ring shape, and may be, for example, a broken ring shape. In this case, the thin portion 13 has a formed shape in which thick portions and thin portions are alternately arranged.
When the disposal part 11 has a large volume, when the colored member 10 is taken out from the resin molding die 20, the thin portion 13 may be broken and the disposal part 11 may be left behind inside the resin molding die 20. There is.
Therefore, as described above, by forming a thick portion at a plurality of locations of the thin portion 13, the thin portion 13 is prevented from being damaged, and the disposal portion 11 is left inside the resin molding die 20. Can be avoided.

The movable core 26 is not limited to the case where the movable core 26 slides on the lower mold 24 and contacts the upper mold 22. The movable core 26 may be slid with respect to the upper mold 22 and abut against the lower mold 24.
Further, the movable core 26 may move in a direction intersecting the upper mold 22 and the lower mold 24. The movable core 26 may move in a direction substantially orthogonal to the upper mold 22 and the lower mold 24 like a so-called slide.

DESCRIPTION OF SYMBOLS 1 Vehicle installation goods 5 Metal luster member (decoration member) 10 Colored member (resin molding product) 11 Waste part 12 Through-hole (fitting hole) 13 Thin part 15 Gate 20 Mold for resin molding 22s Molding surface 22t Hole molding surface 26 Movable Core 27 Tip Surface 28 Projection 29 Depression C Cavity (Ambient Cavity) Ch Cavity P1 Retraction Position P2 Molding Position

Claims (4)

A resin molding die for molding a resin molded product having a through hole,
It is disposed at a retreat position where the portion that becomes the through hole is hollow before resin injection , and includes a movable core that moves to a molding position that fills the cavity after resin injection ,
The movable core has a projecting portion projecting annularly at the periphery of the tip surface,
Of the tip surface, the recess except for the protrusion has the same depth as the peripheral cavity for molding the periphery of the through hole .   2. The resin molding die according to claim 1, wherein the molding position is a position where the movable core approaches or abuts a hole molding surface that is flush with a molding surface that molds the periphery of the through hole. . 3. The gate according to claim 1, wherein when a plurality of the through holes are formed in the resin molded product, a gate is disposed at a position where a total sum of the distances to the through holes is minimized. Mold for resin molding. The through hole is a resin mold according to any one of the preceding claims, characterized in that the decorative member which is a resin molding is fitting hole for fitting 3.

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