JP4988543B2 - Mold and method for producing resin molded product - Google Patents

Description

  The present invention relates to a mold used for injection molding and the like, and in particular, a resin molded product in which a plurality of resin layers are integrated such as an automobile interior such as an instrument panel, a console box, and a door trim. It is suitable as a mold for molding.

Many automobile interior parts such as instrument panels have a cross-sectional structure in which a rigid base material layer and a soft skin layer are integrated. Traditionally, these automobile interior parts were made by molding the base material layer and the skin layer in separate molds and joining them in separate processes. However, for the purpose of simplifying the molding process, Measures have been proposed for forming a substrate and a skin layer in one mold.
For example, Patent Document 1 discloses a method for producing a resin molded product that uses an injection mold having two gates and a runner portion and has a foam layer on the surface of a substrate.

FIG. 9 is an explanatory view showing the behavior of a mold in the conventional method for producing a resin molded product disclosed in Patent Document 1.
In the conventional method of manufacturing a resin molded product, a molding die 100 in which a fixed side mold piece 101 and a moving side mold piece 102 are integrated as shown in FIG. 9 is used. The fixed-side mold piece 101 is a mold piece on the side where molten resin is injected from a resin nozzle (not shown), and includes two runner portions 102 and 103.
In the molding die 100, a first molding space 105 is formed inside when the fixed side mold piece 101 and the moving side mold piece 102 are clamped.
In addition, the mold 100 can move the moving mold piece 102 backward while maintaining an internal sealed state.

When manufacturing a resin molded product having a foam layer on the surface of the substrate, the mold 100 is clamped as shown in FIG. 9B, and the first runner 102 is used as the first mold as shown in FIG. 9C. A molten resin for forming a base material is injected into the molding space 105. As a result, the base material 110 is molded in the first molding space 105.
Thereafter, as in (d), the moving-side mold piece 102 is retracted, and the second molding space 111 appears on the back side of the substrate 110.
Then, as in (e), the molten resin for forming the foam layer is injected from the other runner portion 103 into the second molding space 111. As a result, the foam layer 112 is formed on the back side of the substrate 110.
JP 2002-283389 A

Since the manufacturing method of the resin molded product disclosed in Patent Document 1 can form the base material layer and the foam layer with a single mold, the manufacturing process can be greatly simplified as compared with the conventional method. .
However, according to the method for producing a resin molded product disclosed in Patent Document 1, a foam layer or a skin layer having a certain thickness is formed on the entire surface of the base material, and there is a complaint that the degree of freedom in design and function is low. is there.
That is, in the method described in Patent Document 1, the moving-side mold piece is retracted as a whole, so that a second molding space is formed in the entire area on the back side of the base material. Therefore, the foam layer and the skin layer are provided uniformly on the entire area of the back side of the base material.
However, depending on the shape of the car interior parts, it may not always be necessary to provide a foam layer or skin layer on the entire surface of the base material. The conventional manufacturing methods and molds produce car interior parts of such a design. I can't.

  Therefore, the present invention pays attention to the above-mentioned problems of the prior art, and the first resin layer and the second resin can be molded in one mold, and the second resin layer is partially formed. It is an object of the present invention to provide a molding die and a manufacturing method capable of molding a resin molded product that is missing or thinned.

A related invention for solving the above-described problem is a mold having one mold piece and the other mold piece that move relatively, and the one mold piece and the other mold piece are clamped. A first molding space is formed between the two during the state, and one mold piece is moved relative to the other mold piece to newly form a second molding space in the mold. In a possible mold, a core member capable of projecting from one mold piece toward the molding surface side of the other mold piece, and positioning means for positioning the projecting position of the core member, When the core member is moved relative to the mold piece, the core member maintains a certain relative positional relationship with respect to the other mold piece by the positioning means, and the core member is formed from one mold piece to the molding surface side of the other mold piece. It is a shaping | molding die characterized by becoming a protrusion state toward.

The molding die of this invention has positioning means for positioning the protruding position of the core member, and when the one mold piece is moved relative to the other mold piece, the core member is moved to the other by the positioning means. The relative positional relationship with the mold piece is maintained, and the core member protrudes from one mold piece toward the molding surface side of the other mold piece. Therefore, the second molding space is partially lost or narrowed by the protrusion of the core member.

The invention according to claim 1 is a molding die having one mold piece and the other mold piece that move relatively, and when the one mold piece and the other mold piece are clamped. A first molding space is formed between the two, a molten first resin is injected into the first molding space to form a first molded product, and one mold piece is formed with respect to the other mold piece. The second molding space is newly formed in the molding die, and the molten second resin is injected again into the second molding space, so that the second molding product is integrated with the first molding product. A core member pressed from one mold piece toward the molding surface side of the other mold piece, and a positioning means for positioning the protruding position of the core member, When the mold piece is moved relative to the other mold piece, the core member is moved to the other mold piece by the positioning means. Holding the relative positional relationship, the core member is Ri Do a protruding state towards the one mold half on the molding surface side of the other mold half, positioning means, part of the other mold half or member other than the mold And an interlocking member that interlocks with the core member, and when one mold piece is moved relative to the other mold piece, the interlocking member contacts a part of the other mold piece and the other The mold is characterized by maintaining a certain relative positional relationship with the mold piece .

  The molding die of the present invention also has positioning means for positioning the protruding position of the core member, and when the one mold piece is moved relative to the other mold piece, the core member is moved to the other by the positioning means. While maintaining a predetermined relative positional relationship with the mold piece, the core member protrudes from one mold piece toward the molding surface side of the other mold piece. That is, in the present invention, since the core member is pressed from one mold piece toward the molding surface side of the other mold piece, the core member projects smoothly, and the second molding space is partially lost by the projection of the core member. Or thickness changes. The molding die of the invention is one in which the second resin is injected into the second molding space and the second molded product is molded integrally with the first molded product. Since the resin is not filled, the second resin layer can be partially lost or a resin molded product with a thin second resin layer can be formed.

Positioning means are or recommended has a stopper provided on one mold half, the protruding length of the core member and the contact with the core member when the core member is projected a predetermined length from one mold half It is characterized by being restricted (claim 2 ).

The invention for producing a resin molded product uses the molding die according to claim 1 or 2 , and integrates the second molded product or the foamed layer on the back side of the first molded product, and further the back side of the first molded product. a method for producing a resin molded article, wherein a second molded or foamed layer to form sites that are not present in (claim 3).

  According to the mold of the present invention and the manufacturing method of the present invention, the first resin layer and the second resin layer can be molded in one mold, and the second resin layer is partially The missing resin molded product can be molded. According to the molding die of the present invention and the manufacturing method of the present invention, it is possible to deal with resin molded products of various designs.

Embodiments of the present invention will be further described below.
FIG. 1 is a cross-sectional view of a molding die according to a first embodiment of the present invention, where (a) shows a clamped state, and (b) shows a state in which a moving side mold piece is retracted.
A molding die 1 shown in FIG. 1 includes all the components of the above-described conventional molding die 100, and further includes core members 2 and 3 at two locations. The core members 2 and 3 are provided at a site where the formation of the skin layer is not desired.
The mold 1 is an injection mold in which a fixed-side mold piece 5 and a moving-side mold piece 6 are integrated. The fixed-side mold piece 5 is a mold piece on the side where molten resin is injected from a resin nozzle (not shown), and includes two runner portions 10 and 11.
In the mold 1, a first molding space 15 is formed inside when the fixed-side mold piece 5 and the movable-side mold piece 6 are clamped.
In addition, the mold 1 can move the moving-side mold piece 6 backward with the inside sealed. That is, the mold 1 is a mold having one mold piece and the other mold piece that move relatively.

As described above, the mold 1 includes the core members 2 and 3 as a unique configuration.
Each of the core members 2 and 3 has positioning means for positioning the protruding position of the core members 2 and 3, and when the moving side mold piece 6 is moved backward, the core members 2 and 3 are connected to the moving side mold piece 6. The core members 2 and 3 are in a state of projecting from the stationary mold piece 5 toward the molding surface side of the movable mold piece 6 while maintaining the relative positional relationship before and after the movable mold piece 6 is retracted.

Since the core members 2 and 3 employed in this embodiment have different structures, specific structures will be described individually.
One core member 2 has a return pin (interlocking member) 20 and performs positioning by bringing the return pin 20 into contact with the movable mold piece 6.
That is, the core member 2 is provided with a return pin 20. The return pin 20 is a pin provided in parallel to the core member 2, and is integrated with the core member 2 by the connecting portion 25.

Most of the core member 2 and the return pin 20 are in the fixed-side mold piece 5, and the core member 2 and the return pin 20 are slidable with respect to the fixed-side mold piece 5 from the surface of the fixed-side mold piece 5. It is possible to leave and exit.
That is, holes 22 and 23 are provided in parallel on the molding surface 15 and the mating surface 16 of the fixed-side mold piece 5 toward the inside of the fixed-side mold piece 5. The insides of the hole portions 22 and 23 are connected to a wide gap portion 26.

  The core member 2 and the return pin 20 are in the holes 22 and 23, respectively, and can slide in the holes 22 and 23. The connecting portion 25 is in the gap portion 26. The gap portion 26 is urged by the two coil springs 30 and 31 in a direction in which the core member 2 and the return pin 20 protrude from the fixed-side mold piece 5. That is, the core member 2 and the return pin 20 are pressed toward the moving side mold piece 6.

When the mold 1 is in the clamped state, the core member 2 is urged in the protruding direction by the coil springs 30, 31, but the tip of the return pin 20 comes into contact with the end of the moving side mold piece 6. The core member 2 interlocked with the return pin 20 is stopped at a position where the tip portion forms the same plane as the molding surface 15 of the fixed-side mold piece 5.
On the other hand, when the movable side mold piece 6 is retracted and the mold 1 is opened, the tip of the return pin 20 moves in the protruding direction following the movable side mold piece 6, and the core member 2 is also fixed to the fixed side mold piece 5. Projects from the molding surface 15. At this time, the relative positional relationship between the distal end of the core member 2 and the molding surface 7 of the movable mold piece 6 does not change before and after the movement.

  Next, another core member 3 will be described. The other core member 3 has a stopper pin (stopper) 35. When the core member 3 protrudes from the fixed-side mold piece 5 by a predetermined length, the engaging portion 36 of the stopper pin 35 comes into contact with the core member 3. The protruding length of the core member 3 is regulated.

That is, the fixed-side mold piece 5 is provided with a stopper pin 35. The stopper pin 35 is fixed integrally with the fixed-side mold piece 5 and does not allow relative movement with respect to the fixed-side mold piece 5.
Most of the core member 3 is in the fixed-side mold piece 5, and the core member 3 is slidable with respect to the fixed-side mold piece 5 and can be withdrawn from the surface of the fixed-side mold piece 5.
That is, another hole 37 is provided in the molding surface 15 of the fixed-side mold piece 5, and the core member 3 is slidably disposed. A stopper pin 35 is fixed to the inner part of the hole 37. At the tip of the stopper pin 35, there is an engaging portion 36 that is made thicker than other parts.

A hole 40 is provided in the core member 3. The hole 40 penetrates the core member 3 and is divided into a large-diameter portion 41 and a small-diameter portion 43, and there is a step portion at the boundary portion.
The stopper pin 35 is slidably inserted into the hole 40, and the engaging portion 36 is in the large diameter portion 41.

  The core member 3 is also urged by the coil spring 45 in a direction protruding from the fixed-side mold piece 5. That is, the core member 3 is pressed toward the moving mold piece 6.

When the mold 1 is in the clamped state, the core member 3 is urged in the protruding direction by the coil spring 45, but a part of the core member 3 comes into contact with a part of the moving side mold piece 6. The member 2 is stopped at a position where the tip thereof forms the same plane as the molding surface 15 of the fixed-side mold piece 5.
On the other hand, when the movable mold piece 6 is retracted and the mold 1 is opened, the core member 3 is pushed out by the pressing force of the coil spring 45. However, the protruding length of the core member 3 is regulated by the engaging portion 36 of the stopper pin 35 engaging with the stepped portion of the hole 40, and the core member 3 stops at a certain protruding amount position.
At this time, the relative positional relationship between the distal end of the core member 3 and the molding surface 7 of the movable mold piece 6 does not change before and after the movement.

Next, the operation of the molding die 1 described above will be described following the molding procedure for automobile interior parts.
FIG. 2 to FIG. 4 are explanatory views showing the behavior of the mold when the automobile interior is manufactured using the mold.
For example, when an instrument panel having a skin layer on the surface of a base material is manufactured using the mold 1, the mold 1 is clamped as shown in FIG. 2 (b), and as shown in FIG. 3 (c). The molten resin for forming the base material is injected into the first molding space 15 from one of the runner portions 10. As a result, the base material 50 is molded in the first molding space 15.
Thereafter, the movable-side mold piece 6 is moved backward as shown in FIG. At this time, the previously molded base material 50 is left on the moving-side mold piece 6 and the second molding space 51 appears on the back side of the base material 50.

Here, the mold 1 of the present embodiment includes the core members 2 and 3 as a specific configuration, and when the moving side mold piece 6 is retracted, the core members 2 and 3 are connected to the moving side mold piece 6. Maintain relative positional relationship. Accordingly, the core members 2 and 3 are not separated from the previously formed base material 50, and a part of the second molding space 51 is crushed by the core members 2 and 3.
And the molten resin for skin layer formation is inject | poured into the 2nd shaping | molding space 51 from the other runner part 11 like FIG.4 (e). As a result, the skin layer 52 is formed on the back surface side of the base material 50. Since the core members 2 and 3 are in contact with a specific portion on the back surface side of the base material 50, the core members 2 and 3 are interposed. Resin cannot wrap around the site.
Therefore, when the mold is opened and the molded product is removed as shown in FIG. 4 (f), many skin layers are provided on the back side of the substrate 50. An instrument panel is formed.

Next, another embodiment of the present invention will be described. 5A and 5B are cross-sectional views of a mold according to the second embodiment of the present invention, in which FIG. 5A shows a clamped state, and FIG. 5B shows a state in which the moving side mold piece is retracted.
In the embodiment described above, one of the two core members 2 and 3 has a structure in which the protruding length is regulated by the stopper pin 35, but the stopper pin 35 is omitted as shown in FIG. A structure in which a part of the end face of the core member 3 is brought into direct contact with a part of the movable mold piece 6 may be adopted. That is, in the molding die 60 shown in FIG. 5, the core member 3 has a part 61 that does not constitute a molding surface in a part thereof, and the part 61 functions as an interlocking member and abuts on the moving-side mold piece 6 and the core member. Interlocks with the body part 3. When the movable mold piece 6 is retracted, the interlocking member 61 comes into contact with the movable mold piece 6 to maintain the relative positional relationship between the movable mold piece 6 and the core member 3.

  Further, in the above-described embodiment, the return pin (interlocking member) 20 and the interlocking member 61 are brought into contact with a part of the movable mold piece 6, but the interlocking member may be brought into contact with another member.

  In the above-described embodiments, the core members 2 and 3 are pressed by the springs. However, for example, the return pin (interlocking member) 20 and the interlocking member 61 are coupled to the movable mold piece 6 and pulled out to the movable mold piece 6. The spring is not always necessary if the structure is to be constructed.

  In the embodiment described above, the movable mold piece 6 is moved backward to cause the second molding space 51 to appear, and resin is separately injected into the second molding space 51, but the movable mold piece 6 is moved backward. The present invention can also be applied to applications in which a space is made to appear and the previously injected resin is foamed by forming this space.

In the above-described embodiment, a resin molded product having a part in which the second resin layer is completely missing is molded. However, a resin molded product having a structure in which the second resin layer is partially thin is molded. The present invention can also be applied to the usage.
FIGS. 6 to 9 are explanatory views showing the behavior of the molding die when manufacturing a car interior product having a structure in which the second resin layer is partially thin using the molding die.
The molding die 1 ′ shown in FIGS. 6 to 9 is different from the previous embodiment only in that the length of the stopper pin 35 is short, and the other configuration is the same as the previous embodiment.

That is, in the mold 1 ′, when the movable mold 6 is retracted and the mold 1 is opened, the core member 3 is pushed out by the pressing force of the coil spring 45, and the protruding length of the core member 3 is related to the engagement of the stopper pin 35. The joint portion 36 is regulated by engaging with the stepped portion of the hole 40, and the core member 3 stops at a position of a constant protrusion amount.
At this time, the relative distance between the tip of the core member 3 and the molding surface 7 of the moving-side mold piece 6 is slightly larger than that before the movement. Therefore, the core member 3 is slightly separated from the previously formed base material 50. That is, in the mold 1 ′, the second molding space 51 exists on the tip side of the core member 3, but the thickness thereof is thinner than other parts.

To explain sequentially, the mold 1 ′ is clamped as shown in FIG. 6 (b), and the molten resin for forming the substrate is injected into the first molding space 15 as shown in FIG. 7 (c). The base material 50 is molded in the molding space 15.
Thereafter, the movable-side mold piece 6 is moved backward as shown in FIG. At this time, the previously molded base material 50 is left on the moving-side mold piece 6 and the second molding space 51 appears on the back side of the base material 50.

Here, in the mold 1 ′ of the present embodiment, when the moving-side mold piece 6 is retracted, only one core member 2 maintains the relative positional relationship with the moving-side mold piece 6, and the other core member 3. Is slightly retracted relative to the moving mold piece 6.
Accordingly, one core member 2 does not leave the previously molded base material 50 as in the previous embodiment, and a part of the second molding space 51 is crushed by the core member 2.
On the other hand, in the other core member 3, the engaging portion 36 of the stopper pin 35 abuts against the core member 3 and the protruding length of the core member 3 is restricted. It is a position slightly away from the base material 50 formed in the above.
That is, when the moving-side mold piece 6 is retracted, the core member 3 maintains a certain relative positional relationship with respect to the moving-side mold piece 6 by the stopper pin 35, and the core member is relative to the moving-side mold piece 6. Stop at a slightly retracted position.

And the molten resin for skin layer formation is inject | poured into the 2nd shaping | molding space 51 from the other runner part 11 like FIG.8 (e). As a result, the skin layer 52 is formed on the back side of the base material 50, but the core member 2 is in contact with a specific part on the back side of the base material 50. Can not get around the resin.
Moreover, since the distance of the core member 3 and the back surface side of the base material 50 is short as compared with other parts, the second molding space 51 is narrow in the part of the core member 3.
Therefore, when the mold is opened and the molded product is removed as shown in FIG. 8 (f), many skin layers are provided on the back side of the base material 50. In the other part, an instrument panel having a thin skin layer is formed.

It is sectional drawing of the shaping | molding die in 1st embodiment of this invention, (a) shows a clamping state, (b) shows the state which retracted the movement side mold piece. It is explanatory drawing which shows the behavior of the shaping | molding die at the time of manufacturing a motor vehicle interior goods using a shaping | molding die. It is explanatory drawing which shows the behavior of the shaping | molding die at the time of manufacturing a motor vehicle interior goods using a shaping | molding die, and shows the behavior following FIG. It is explanatory drawing which shows the behavior of the shaping | molding die at the time of manufacturing a motor vehicle interior goods using a shaping | molding die, and shows the behavior following FIG. It is sectional drawing of the shaping | molding die in 2nd embodiment of this invention, (a) shows a clamping state, (b) shows the state which retracted the movement side mold piece. It is explanatory drawing which shows the behavior of a shaping | molding die at the time of manufacturing the automotive interior goods of the structure where the 2nd resin layer is partially thin using a shaping | molding die. It is explanatory drawing which shows the behavior of the shaping | molding die at the time of manufacturing a motor vehicle interior goods using a shaping | molding die, and shows the behavior following FIG. It is explanatory drawing which shows the behavior of the shaping | molding die at the time of manufacturing a motor vehicle interior goods using a shaping | molding die, and shows the behavior following FIG. It is explanatory drawing which shows the behavior of the shaping | molding die in the manufacturing method of the prior art resin molded product disclosed by patent document 1. FIG.

DESCRIPTION OF SYMBOLS 1,1 'Mold 2,3 Core member 5 Fixed side mold piece 6 Moving side mold piece 15 First molding space 20 Return pin (interlocking member)
30, 31 Coil spring 35 Stopper pin (stopper)
45 Coil spring 50 Base material 51 Second molding space 52 Skin layer

Claims (3)

A mold having one mold piece and the other mold piece that move relative to each other when the one mold piece and the other mold piece are clamped. A space is formed, a molten first resin is injected into the first molding space to form a first molded product, and one mold piece is moved relative to the other mold piece to form a mold. A molding die in which a second molding space is newly formed and molten second resin is injected again into the second molding space to mold the second molding integrally with the first molding. The core member pressed from the one mold piece toward the molding surface side of the other mold piece, and positioning means for positioning the protruding position of the core member, and the one mold piece with respect to the other mold piece The core member maintains a relative positional relationship with respect to the other mold piece by the positioning means. , The core member is Ri Do a protruding state towards the one mold half on the molding surface side of the other mold half,
The positioning means has an interlocking member that is in contact with a part of the other mold piece or a member other than the mold and interlocks with the core member, and moves one mold piece relative to the other mold piece. forming the shape type you characterized by maintaining a constant relative positional relationship between the partial interlocking member of the other mold half and abuts the other mold half time. It positioning means has a stopper provided on one mold half, in which the core member for restricting the projecting length of the core member and the contact with the core member when projecting a predetermined length from one mold half The molding die according to claim 1 . The mold according to claim 1 or 2 , wherein the second molded product or the foamed layer is integrated on the back side of the first molded product, and the second molded product or the foamed layer is further formed on the back side of the first molded product. A method for producing a resin molded product, wherein a non-existing site is formed.

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