JP3274942B2 - Composite molding method and injection molding machine - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a composite molding method and an injection molding machine, and more particularly to a composite molding method and an injection molding machine.
The present invention relates to a novel improvement for injecting a second material into a material to completely fill a cavity with a first material and to obtain a composite molded article having a good surface shape.

[0002]

2. Description of the Related Art Conventionally, as this type of molding method, a type of material is generally injected into a cavity to form a molded product.

[0003]

Since the conventional molding method is configured as described above, there are the following problems. In other words, in the case of a molded product having a complicated shape or a curved surface having a large area, it is difficult to obtain a molding surface according to the shape of the cavity, and a concave portion due to sink marks or wrinkles is formed on the surface. was there. In order to eliminate such recesses and wrinkles, extremely complicated injection conditions, pressure-holding conditions, and the like must be set and controlled in accordance with the cavity shape, and the yield of injection molding can be improved. It was extremely difficult.

[0004] The present invention has been made to solve the above problems, and in particular, the first material is injected into the cavity to inject the second material into the first material. An object of the present invention is to provide a composite molding method and an injection molding machine capable of completely filling a tee to obtain a composite molded product having a good surface shape.

[0005]

According to the present invention, there is provided a composite molding method comprising: a first injection cylinder connected to a first gate of a fixed die on a main bed for injecting a first material; A valve gate positioned outside one gate, a bubble gate pin provided through the manifold and the bubble gate communicating with the bubble gate and operated by a cylinder type actuator, and the first injection cylinder is orthogonal to the main bed. Using an injection molding machine comprising a second injection cylinder for injecting a second material into each of the manifolds provided, with each of the valve gates protruding into a cavity formed by a fixed mold and a movable mold. After injecting the first material into the cavity through the first gate and filling the cavity, the valve gate pins Is retracted to open the bubble gate, a second material is injected into the first material from the valve gate through the second injection cylinder, and the first material is shaped by the second material into the cavity. It is a method of filling along.

The composite molding method according to the present invention is a method in which the first material and the second material are the same.

[0007] More specifically, there is provided a method in which the first material and the second material are different materials.

More specifically, the first material and the second material use an engineering plastic, and the temperature of the second material is higher than that of the first material.

More specifically, a second axis direction of the second injection cylinder is orthogonal to a first axis direction of the first injection cylinder, and the second injection cylinder moves along the first axis direction. It is a way to make it.

In an injection molding machine according to the present invention, a first material is introduced into a cavity formed by a fixed mold and a movable mold from a first injection cylinder joined to the fixed mold via a first gate of the fixed mold. After injection, in an injection molding machine for injecting a second material into the first material through a second injection cylinder, the injection molding machine is formed in the fixed mold to guide the second material into the cavity. A plurality of manifolds each having a plurality of manifolds located outside the first gate and a plurality of valve gate pins provided on the fixed mold and provided to freely open and close to open and close a plurality of valve gates communicating with each of the manifolds and the cavity. Wherein the first gate is located at the center of the cavity, and each of the valve gates is located outside the first gate. The second injection cylinder is located on a peripheral side of the biteity, and a second axis direction of the second injection cylinder is orthogonal to a first axis direction of the first injection cylinder, and the second injection cylinder is provided with the first injection cylinder. The second cylinder is provided on the side of the main bet provided, and the second cylinder is movably provided on the side, and each of the valve gate pins passes through each of the valve gates into the cavity. The first material is injected into the cavity while being protruded.

[0011]

In the composite molding method and the injection molding machine according to the present invention, the first material is injected into the cavity formed by the fixed mold and the movable mold via the first injection cylinder, and then solidified. Before or during the simultaneous injection, the first material is pressed by the pressure of the second material by injecting a second material made of a material different from the first material, such as a resin foam, from the second injection cylinder. Unfolded,
The first material is completely filled to every corner of the cavity.
Therefore, the surface of the first material is free from depressions and wrinkles due to sinks, and a high-quality molded product can be obtained.

[0012]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS Preferred embodiments of a composite molding method and an injection molding machine according to the present invention will be described below in detail with reference to the drawings. 1 to 8 are a conceptual configuration diagram and an operation configuration diagram showing an injection molding machine to which the composite molding method according to the present invention is applied.

In FIG. 1, reference numeral 1 denotes a fixed type provided on a fixed platen 32. A movable type 2 is provided on the fixed type 1 so as to be able to freely contact and separate (open and close). A cavity 3 is formed by the molds 1 and 2. The movable mold 1 is configured to be able to open and close and open and close the mold via a well-known mold clamping mechanism (not shown).

A first injection cylinder provided in a first injection unit 5c is provided at a first nozzle touch portion 4a of a first gate 4 formed in the fixed die 1 and communicated with a central portion of the cavity 3. 5 is in contact with the first nozzle 5a, and the second nozzle 7a is provided on the side 30a of the main bed 30 on which the fixed mold 1 and the first injection cylinder 5 are provided.
A sub bed 31 having a second screw 7b and a second injection cylinder 7 provided in the second injection unit 7c is provided so as to be movable in the direction of arrow A.

That is, the second axial direction B of the second injection cylinder 7 is the same as the first axial direction C of the first injection cylinder 5.
And the second injection cylinder 7
The nozzle 7a is in contact with the second nozzle touch portion 6a of the manifold 6 of the fixed die 1.

Valve gate pins 8cA of a plurality of cylinder-type actuators 8c provided in the fixed mold 1 penetrate through the manifold 6, and the manifold 6
It penetrates back and forth so as to open and close through a valve gate 8a formed between the cavity 3 and the cavity 3. On the back side of the cavity 3, an ejector 34 for taking out a molded product is provided.
3 is configured to be operated by a knock bolt 35 that can be retracted and provided. Therefore, each of the valve gates 8a and the valve gate pins 8cA are located on the outer peripheral side of the cavity 3 outside the first gate 4.

Next, a method of performing composite molding (sandwich molding) using the above-described injection molding machine 10 will be described.
First, as shown in FIG. 1, each valve gate 8a is closed by advancing each valve gate pin 8cA, and the first
When the first material 11 in the injection cylinder 5 and the second material 12 in the second injection cylinder 7 are sufficiently plasticized, the first material 11 is injected from the first injection cylinder 5 into the cavity 3. As shown by 2, the first material 11 is in a state of being substantially filled in a portion of the cavity 3 except for details.

Next, each valve gate pin 8cA is retracted by each cylinder type actuator 8c, each valve gate 8a is opened, and the second injection cylinder 7 injects the second material 12 made of resin foam. Then, this second
As shown in FIG. 4, the material 12 is injected into the first material 11 previously filled in the cavity 3, and at the same time, the second material is foamed. The material 11 is pushed, and the first material 11 is uniformly filled to every corner along the shape in the cavity 3. Then, as shown in FIG. 5, each valve gate pin 8cA is advanced slightly to close each valve gate 8a from the open state, and the movable mold 2 is pulled together with the movable platen 33 to open the mold (shown in FIG. 6).
The molded article 100 is moved by the ejector 34 to the movable mold 2.
Can be removed and removed. The next cycle can be started from the mold open state in FIG. According to the results of the above-described injection molding experiment, for example, even in the case of a large molded product such as a door mirror mounted on an automobile door, no concave portion or wrinkle due to sink is seen on the surface.
It has been confirmed that a yield of 00% can be achieved.

In the above-described embodiment, the case where a foam material is used as the second material 12 has been described. However, the same applies to the case where ordinary resin materials having different degrees of melting are used, without being limited to the foam material. It was confirmed that the effect was exhibited. The first material 11 and the second material 12 are not limited to different materials as described above, and may be the same or equivalent. The first material 11 and the second material 12 are made of engineering plastic (for example, well-known PPS, PBT, PTO, etc. are particularly effective), and the second material 12 is used at a higher temperature than the first material 11. The case is also suitable. That is, the first material 1
1 can be formed at a low temperature and the second material 12 can be formed at a high temperature, so that the fusion strength of each material can be improved. Further, in the case of resins that are difficult to fuse with each other, the second material 12 side may be heated to a high temperature to change the internal shape and not to be structurally removed. Further, the difference in shrinkage and the difference in thickness between the skin layer and the core layer caused by the time lag injection performed in the above-described manufacturing method can be improved by controlling the temperature.

[0020]

Since the present invention is configured as described above, the following effects can be obtained. That is,
Since the first material injected into the cavity is pressed from the inside by the second material injected by the second injection cylinder, the first
There is no concave portion or wrinkle due to sink marks on the surface of the material, it is possible to control molding defects due to the difference in shrinkage due to the combination of different materials and the effect of the resin temperature, and it is possible to always obtain a molded product with a 100% yield.

[Brief description of the drawings]

FIG. 1 is a sectional view showing an injection molding machine applied to a composite molding method according to the present invention.

FIG. 2 is a sectional view showing an injection state of a first material of FIG. 1;

FIG. 3 is a sectional view showing a state where a gate valve pin is removed.

FIG. 4 is a cross-sectional view of a state where a second material is injected.

FIG. 5 is a sectional view showing a state in which a gate valve is closed.

FIG. 6 is a sectional view showing a mold opening.

FIG. 7 is a cross-sectional view of a state where a molded article has been ejected.

FIG. 8 is a sectional view showing the mold opening after the ejection.

[Explanation of symbols]

 Reference Signs List 1 fixed type 2 movable type 3 cavity 5 first injection cylinder 6 manifold 7 second injection cylinder 8c cylinder type actuator 11 first material 12 second material 30 main bed 30a side part C first axial direction B second axial direction 8cA Valve gate pin 8a Valve gate 4 First gate

Claims (6)

(57) [Claims] 1. A first fixed type (1) on a main bed (30).
A first injection cylinder (5) connected to the gate (4) and injecting the first material (11); and a valve gate (8a) provided on the fixed mold (1) and located outside the first gate (4). ), A bubble gate pin (8cA) provided through the manifold (6) communicating with each of the bubble gates (8a) and the bubble gate (8a) and operated by a cylinder type actuator (8c), and the main bed (30) using an injection molding machine comprising a second injection cylinder (7) which is provided orthogonal to the first injection cylinder (5) and injects a second material (12) into each of the manifolds (6). In a state where each of the bubble gates (8a) protrudes into a cavity (3) formed by the fixed mold (1) and the movable mold (2), the first material is passed through the first gate (4). After injecting (11) into the cavity (3) and filling the cavity (3), the valve gate pins (8cA) are retracted to remove the valve. Open the bullgate (8a) and open the second injection cylinder
A second material (12) is injected into the first material (11) from the valve gate (8a) through (7), and the first material (11) is injected into the cabinet by the second material (12). A composite molding method characterized by filling the tee along the shape of the tee (3). 2. The first material (11) and the second material (12)
The composite molding method according to claim 1, wherein the composite molding method is made of the same material. 3. The composite molding method according to claim 1, wherein the first material (11) and the second material (12) are made of different materials. 4. The first material (11) and the second material (12) use an engineering plastic, and the first material
The composite molding method according to any one of claims 1 to 3, wherein the temperature of the second material (12) is higher than (11). 5. A second axial direction of the second injection cylinder (7).
(B) is orthogonal to the first axial direction (C) of the first injection cylinder (5), and the second injection cylinder (7) is moved along the first axial direction (C). Claim 1.
5. The composite molding method according to any one of items 1 to 4. 6. A fixed injection mold (1) from a first injection cylinder (5) joined to the fixed die (1) in a cavity (3) formed by the fixed die (1) and the movable die (2). After injecting the first material (11) through the first gate (4), the second injection cylinder (7)
In the injection molding machine configured to inject the second material (12) into the first material (11) through the above, the second material (12) formed in the stationary mold (1) is filled with the cavity ( A plurality of manifolds (6) located outside the first gate (4) for guiding to (3), and each manifold (6) provided in the fixed die (1) communicates with the cavity (3). A plurality of cylinder-type actuators (8c) having valve gate pins (8cA) provided to open and close the valve gates (8a) and the manifold (6) in order to open and close the plurality of valve gates (8a). Wherein the first gate (4) is located at the center of the cavity (3), and each of the valve gates
(8a) is located outside the first gate (4) on the peripheral side of the cavity (3), and the second injection cylinder (7) is in the second axial direction (B). 1st axis direction of cylinder (5)
(C), the second injection cylinder (7) is provided on a side (30a) of a main bed (30) provided with the first injection cylinder (5), and Cylinder (7)
The valve gate pins (8cA) are movably provided on the side portions (30a), and the valve gate pins (8cA) penetrate the bubble gates (8a) and protrude into the cavities (3). When the first material (11) is in the cavity,
(3) An injection molding machine configured to be injected into the inside.