JPH07195432A - Method and mold for effecting stamping-molding integral with skin material - Google Patents

Abstract

PURPOSE:To provide a method and mold for effecting stamping-molding integral with a skin material, decreasing sink and warping through uniform molding pressure. CONSTITUTION:The mold is constituted of a first core movable mold 20 to be movable separately of a movable mold 40 and a second movable mold 30 secured to the first core movable mold 20, and the timing of injection during the period of being compressed with a stationary mold 10 through the movement of the first core movable mold 20 from the gate of the stationary mold 10 being opposite to the first core movable mold 20 is delayed further than the timing of injection during the period of being compressed with the stationary mold 10 through the movement of the second core movable mold 30 from the gate of the stationary mold 10 being opposite to the second core movable mold 30. Furthermore, the timing of injection during the period of being compressed with the stationary mold 10 through the movement of the movable mold 40 from the gate of the stationary mold 10 being opposite to the movable mold 40 is also delayed further than the timing of injection from the gate of the stationary mold being opposite to the first core movable mold 20.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a skin-integrated stamping molding die for integrally molding a skin material on the surface of a base material made of a thermoplastic resin, and a molding method.

[0002]

2. Description of the Related Art Generally, for automobile interior parts, multi-layer molded articles in which various skin materials are attached to the surface of a base material made of a thermoplastic resin are often used. This multi-layer molded product is formed by arranging a skin material between opposing molds and clamping the mold, and by injecting a molten synthetic resin between the skin material and one of the molds by compression molding or the like. There is. However, in the case of a large molded product such as a door trim, the molten resin is supplied to the cavity from a large number of gates (so-called multipoint gate system).

[0003]

When the resin is supplied from a large number of gates as described above, as shown in FIG. 5, the gate and the molten resin J injected from the gates are applied to both molds 61, 61.
62, the skin material H set in the mold moves together with the molten resin J, and wrinkles M are generated in the weld portion which is a joint portion between the molten resins. There was an inconvenience. Further, when a large amount of resin is supplied to the cavity, there is a disadvantage that the skin material near the gate is significantly deteriorated. Further, if the number of gates is increased, the structure of the die becomes complicated, and adjustment between gates becomes troublesome.

The object of the present invention is to prevent wrinkles from being generated in the welded portion, to adjust the amount of resin injected from the gate to prevent deterioration of the skin material near the gate, and to secure a long flow length of the molten resin to ensure gate flow. (EN) Provided are a skin-form stamping molding die and a molding method capable of reducing the number of molds, simplifying the structure of the mold on the gate side, reducing the adjustment between gates, and reducing sink marks and warpage due to uniform molding pressure. Especially.

[0005]

A skin-integrated stamping molding die according to claim 1 of the present invention comprises a fixed die having a plurality of gates, and a movable die arranged so as to face the fixed die. A skin formed by arranging a skin material between a fixed mold and a movable mold, injecting a resin as a base material from the fixed mold, and clamping the mold with the skin material and the base material integrally molded. In the integrated stamping molding die, the movable die has a first core movable die that is movable separately from the movable die, and a second core movable die attached to the first core movable die. When the mold is formed and the second core movable mold is moved and compressed with the fixed mold, the first core is injected from the gate of the fixed mold facing the second core movable mold. The gate of the fixed mold facing the first core movable mold when the core movable mold is moved and compressed with the fixed mold. Delaying the timing of al injected,
Furthermore, injection from the gate of the fixed mold facing the movable mold when the movable mold is moved and compressed with the fixed mold is injected from the gate of the fixed mold facing the first core movable mold. It is characterized in that it is formed later than the injection timing.

At this time, the second core movable mold is arranged in the center of the movable mold, the first core movable mold is arranged on the outer peripheral side of the second core movable mold, and the movable mold is arranged in the second middle. It is preferable that the movable die is arranged on the outer peripheral side of the movable die and the surface pressure of each movable die is gradually increased toward the outside.

According to a third aspect of the present invention, a method of stamping and forming a skin integrated with a fixed metal having a plurality of movable dies and a plurality of gates facing the plurality of movable dies and injecting a molten resin serving as a base material. A mold is used to dispose a skin material between a fixed mold and a movable mold, the movable mold is moved, and molten resin is injected from a gate facing the movable mold to perform pressure compression molding. In the method for integrally forming a skin, the primary compression molding is performed by moving the core movable mold in the portion of the skin material and the base material to be molded first, and injecting the molten resin from the gate facing the core movable mold. Then, the core movable mold is moved with the timing delayed from the primary compression molding, and the molten resin is injected from the gate facing the core movable mold to perform the secondary compression molding. Movable metal with delayed timing when molding Characterized by integrally formed by performing compression molding by moving the skin material and the base material on the entire surface. At this time, it is preferable that the surface pressure of each movable mold be gradually increased toward the outside.

[0008]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS An embodiment of the present invention will be described below with reference to the drawings. The members, arrangements, and the like described below do not limit the present invention and can be variously modified within the scope of the gist of the present invention.

FIGS. 1 to 4 show an embodiment of the present invention, and FIG. 1 shows a molding die and a molding process, in which a mold clamping start state by a second core movable mold is shown. FIG. 2 is a sectional view of a step showing a mold clamping state by a fixed mold and a second core movable mold, and FIG. 3 is a mold clamping state by a fixed mold and a first core movable mold. FIG. 4 is a cross-sectional view of the process, and FIG. 4 is a cross-sectional view of the process showing a clamped state of the fixed mold and the movable mold.

The molding apparatus S of the present embodiment includes a fixed mold 10, a first core movable mold 20, a second core movable mold 30, a movable mold 40, and core driving devices 51, 52. And a plurality of gates 11a as main constituent elements.

A skin material holding frame (not shown) for holding the skin material H is arranged on the outer periphery of the stationary die 10 of this example. The skin material H is held by the skin material holding frame.
An unillustrated extrusion molding machine or injection molding machine is attached to the fixed-side mold 10 of this example, and the synthetic resin J in a molten state is supplied from the extrusion-molding machine or injection molding machine to the fixed-side mold 10.
Supplied on the mold surface. The skin material H can be attached by vacuum suction or the like instead of the frame body.

The fixed mold 10 of this example has a desired mold shape, a molten resin J serving as a base material is injected onto the upper surface of the mold, and a plurality of gates 11a are opened on the upper surface of the fixed mold 10. Is formed. These gates 11a are the first
Core movable mold 20, second core movable mold 30, movable mold 4
0 is adjusted by the valve gate 11 so that the molten synthetic resin J is injected with a time difference.

A first core movable mold 20, a second core movable mold 30, and a movable mold 40 are arranged so as to face the fixed mold 10. In the movable mold 40, a first core movable mold 20 that is movable separately from the movable mold 40 and a second core movable mold 30 attached to the first core movable mold 20 are formed. Has been done. These first core movable mold 20 and second core
The core movable mold 30 is configured to be moved by the drive devices 51 and 52, and pressurize and compress the skin material H and the resin J together with the fixed mold 10.

As the driving devices 51 and 52, known devices such as hydraulic devices, pneumatic devices and spring type devices can be used. For example, when using a spring type, 20-80k
Adjust to gf / cm ² . These hydraulic devices, pneumatic devices, springs, etc. are configured so that the molding pressure can be adjusted freely.

In the present example, the second core movable mold 30 is arranged in the center of the movable mold 40, and the first core movable mold 20 is arranged on the outer peripheral side of the second core movable mold 30. , Movable mold 40
Are arranged on the outer peripheral side of the second core movable die 30. The surface pressure of each of the movable molds 20, 30, and 40 is configured to be gradually increased toward the outside.

In addition, when the second core movable mold 30 is moved and compressed together with the fixed mold 10, it is injected from the gate 11a of the fixed mold 10 facing the second core movable mold 30. From the timing, the timing of pouring from the gate 11a of the fixed mold 10 facing the first core movable mold 20 when the first core movable mold 20 is moved and compressed with the fixed mold 10. Is configured to be delayed.

Further, the movable mold 40 is moved to move the fixed mold 1
0 is injected from the gate 11a of the fixed mold 10 facing the movable mold 40 at the time of pressure compression, and is injected from the gate 11a of the fixed mold 10 facing the first core movable mold 20. It is formed later than the timing.

The fixed mold 1 near the gate 11a
The moving speed, time, timing, etc. of the movable mold are adjusted so that the clearance between 0 and the movable molds 20, 30, 40 is sufficient during the injection of the resin J.

As the material of the skin material H used in the present invention, woven cloth, non-woven cloth, thermoplastic resin such as polyolefin, vinyl chloride and nylon, and thermoplastic elastomer such as polyolefin series, polyester series, urethane series and vinyl chloride series. Sheet, film. Further, it is possible to use one of the above materials alone or a laminate of two or more thereof.

In order to give a softer feel, a foam sheet made of polypropylene, polyethylene, urethane or the like is attached to the back surface of the skin material H to protect it from the heat of the molten resin during molding, It is also possible to use a laminate in which a cloth, a sheet, or the like is attached to the back surface for the purpose of strengthening the adhesive force of the material. When using these skin materials H, preheating may be performed prior to supply in order to adjust the tensile stress and elongation of the skin material H.

The resin J used as the base material in the present invention is
For example, polypropylene, polyethylene, polystyrene, acrylonitrile-styrene-butadiene copolymer, thermoplastic resin such as nylon, ethylene-propylene block copolymer, thermoplastic elastomer such as styrene-butadiene block copolymer, compression molding, injection Any of those commonly used for molding and extrusion can be used. Further, those containing an additive such as an inorganic filler, a filler pigment such as glass fiber, a lubricant, an antistatic agent or the like can be appropriately used.

Next, a method of integrally molding the base material and the skin material by using the molding die having the above structure will be described.
First, the skin material H is disposed between the fixed mold 10 and the movable molds 20, 30, 40. And the movable molds 20, 3
The molten resin J is injected from the gate 11a facing the movable molds 20, 30 and 40 while moving 0 and 40, and pressure compression molding (stamping molding) is performed. That is, as shown in FIG. 1, the second core movable mold 30 is moved in the skin material portion and the base material portion to be molded first, and the gate facing the second core movable mold 30 at this time. Molten resin J is injected from 11a. Then, the second movable core die is pressed and compressed to perform the primary stamping compression molding. By doing so, the resin J becomes the second core movable mold 30 and the fixed mold 1
It is molded with 0 and is pushed by the second core movable mold 30 to move outward.

The first core movable mold 20 is moved with a delay in the timing of the primary stamping compression molding. At this time, the molten resin J is injected from the gate 11a facing the first core movable die 20. And as shown in FIG.
Next stamping compression molding is performed. At this time, the resin pushed outward by the first stamping compression molding is molded together with the resin injected from the gate 11 a facing the first core movable mold 20 and becomes integral.

The movable die 40 is moved with a delay in the timing of the secondary stamping compression molding. At this time, the molten resin J is injected from the gate 11a facing the movable mold 40. Then, as shown in FIG. 4, third stamping compression molding is performed. At this time, the resin pushed outward by the secondary stamping compression molding is molded and integrated with the resin injected from the gate 11a facing the movable mold 40.

The timing of the resin J is adjusted by the gate valve 11. In this example, when molding is performed sequentially, the timing is delayed to move the movable mold to perform compression molding to form the skin material and the base material. When integrally molding the
The surface pressure of each movable mold is gradually increased toward the outside. In the above embodiment,
By adjusting the pressure of the driving devices 51 and 52, the molding pressure can be changed to mold a product suitable for various resins and skin materials.

As described above, in the present embodiment, the compression is performed sequentially from the central portion toward the outside, so that when the primary compression molded resin is secondary compressed in the central portion. It merges with the injection resin and flows outward due to compression. Finally, the entire surface is filled with the resin.

[0027]

As described above, according to the outer skin-integrated stamping molding die and molding method of the present invention, the first core movable die movable independently of the movable die, and the first core movable die. A second core movable mold attached to the mold is formed, and the fixed mold is opposed to the second core movable mold when the second core movable mold is moved and compressed with the fixed mold. From the timing of injecting from the gate of the above, the timing of injecting from the gate of the fixed mold facing the first movable core mold when the first movable core mold is moved and compressed with the fixed mold Delay,
Furthermore, injection from the gate of the fixed mold facing the movable mold when the movable mold is moved and compressed with the fixed mold is injected from the gate of the fixed mold facing the first core movable mold. Since the resin is formed later than the injection timing, the resin sequentially moves to the outer side, whereby wrinkles at the weld can be prevented. Also, since the resin flow length can be kept long, the amount of resin injected from the gate can be adjusted to prevent deterioration of the skin material near the gate, and the flow length of the molten resin can be secured long to reduce the number of gates. The structure of the mold can be simplified, the adjustment between the gates can be reduced, and sink and warp can be reduced by making the molding pressure uniform.

[Brief description of drawings]

FIG. 1 is a cross-sectional view showing a molding die and a molding process of an embodiment according to the present invention, showing a state where a second core movable mold is used for clamping.

FIG. 2 is a sectional view of a step showing a mold clamping state by a fixed mold and a second core movable mold.

FIG. 3 is a sectional view of a step showing a mold clamping state by a fixed mold and a first core movable mold.

FIG. 4 is a sectional view of a step showing a mold clamping state between a fixed mold and a movable mold.

FIG. 5 is a cross-sectional explanatory view of a main part for explaining a conventional example.

[Explanation of symbols]

 10 Fixed Mold 11 Gate Valve 11a Gate 20 Movable Mold (First Core Movable Mold) 30 Movable Mold (Second Core Movable Mold) 40 Movable Mold 51,52 Drive Device H Skin Material J Synthetic Resin

─────────────────────────────────────────────────── ───

[Procedure amendment]

[Submission date] April 26, 1994

[Procedure Amendment 1]

[Document name to be corrected] Drawing

[Correction target item name] All drawings

[Correction method] Change

[Correction content]

[Figure 1]

[Fig. 2]

[Figure 3]

[Figure 4]

[Figure 5]

─────────────────────────────────────────────────── ─── Continuation of the front page (51) Int.Cl. ⁶ Identification code Internal reference number FI technical display location B29L 9:00

Claims (4)

[Claims] 1. A fixed mold provided with a plurality of gates, a movable mold arranged to face the fixed mold, and a skin material disposed between the fixed mold and the movable mold to fix the fixed mold. A skin-integrated stamping molding die obtained by injecting a resin serving as a base material from a die and clamping the die by integrally molding a skin material and a base material, wherein the movable die includes the movable die and Separately movable first core movable mold and second core movable mold attached to the first core movable mold are formed, and the second core movable mold is moved to a fixed mold. From the timing of injecting from the gate of the fixed mold facing the second movable core mold at the time of pressurizing and compressing The timing of injection from the gate of the fixed mold facing the first core movable mold is delayed, and the movable mold is moved to form the fixed mold. The injection from the gate of the fixed mold facing the movable mold at the time of compression under pressure is delayed from the timing of injection from the gate of the fixed mold facing the first core movable mold. A die for stamping molding with integral skin. 2. A movable mold, wherein the second core movable mold is arranged in the center of the movable mold, and the first core movable mold is arranged on the outer peripheral side of the second core movable mold. 2. The skin-integrated stamping molding according to claim 1, wherein the second core movable die is arranged on the outer peripheral side, and the surface pressure of each of the movable dies gradually increases toward the outside. Mold. 3. A movable mold and a movable mold using a plurality of movable molds and a fixed mold having a plurality of gates facing the plurality of movable molds and for injecting a molten resin serving as a base material. First, in a skin-integrated molding method, in which a skin material is disposed between the mold and a movable mold, and a molten resin is injected from a gate facing the movable mold to perform pressure compression molding. The primary compression molding is performed by moving the movable core die in the skin material and the base material and injecting the molten resin from the gate facing the movable core die to perform the primary compression molding. And moving the core movable mold while injecting the molten resin from the gate facing the core movable mold.
When sequentially forming the next compression molding, the timing is delayed and the movable mold is moved to perform compression molding to integrally mold the skin material and the base material on the entire surface, and the stamping molding is integrated with the skin. Method. 4. The skin-integrated stamping molding method according to claim 3, wherein the surface pressure of each of the movable molds is gradually increased toward the outside.