JPH03292115A - Film insert injection molding machine - Google Patents

Abstract

PURPOSE:To enable integral molding without causing dirt and a flaw on a design indication face by providing a gate part which injects molding material to the rear side of an insert film placed on the placing face of a cavity, a mechanism for holding a molded form to a top force at a time of mold opening and an ejector part which extrudes the molded form downward to the top force. CONSTITUTION:An insert film 8 is set in a horizontal state on the placing face 41 of a cavity face 40 in the lower part of a bottom force 1 while upward directing the rear 81 side of a design indication face 80 side and mold clamping is performed. When the molding material is injected toward the rear 81 side from the tunnel gate part 20 of a top force 2 and filled, the insert film 8 is pushed on the placing face 41 by the injection pressure, closely stuck and held. The molding material is not infiltrated into the indication face 80 side and filled into a cavity 4 and integrally molded. Then at a time of mold opening, the top force 2 is raised and moved. When the molded force is bonded and held to the cavity face 42 in the upper part by a holding mechanism 12 and reaches the setting position, holding of an ejector part 22 is released. The extruded molded form 4A is separated from a second ejector pin 225 and taken out.

Description

DETAILED DESCRIPTION OF THE INVENTION [Industrial Application Field] The present invention relates to a film insert injection molding machine.

[Prior Art] Conventionally, for example, resin films with designs such as letters, symbols, pictures, patterns, etc. printed on the back side and transparently displayed on the front side, metal films with the designs formed on the front side, etc. A thin decorative film with a thickness of about 0.3 mm or less is set as an insert film in the capitay formed on the mating surfaces of the fixed mold and the movable mold, and a resin molding material of a certain thickness is integrally placed on the back side. In the case of molded products, so-called film insert molded products, a horizontal opening injection molding machine or a vertical opening injection molding machine was used.

[Problems to be solved by the invention] However, when using a side-opening injection molding machine, the cavity surface for setting the insert film is in a vertical position, so the insert film cannot be
A means to securely hold it in place is required. As the means, for example, static electricity is applied to the insert film in advance using a static electricity generator or the like, and the insert film is adsorbed to the cavity surface using the electrostatic action, or an adhesive is applied to a part of the exposed surface of the insert film. A method is used in which the material is bonded to the cavity surface.

In the method using static electricity, vibrations caused when the movable mold moves toward the fixed mold during mold clamping, and other factors cause problems such as the insert film peeling off from the fixed position or misalignment. For this reason, the defect rate of molded products was as high as about 20%.

Further, in the case of using an adhesive, a molding material is injection molded on the back side of the insert film, and the design display surface of the molded product integrally molded with the insert film may be stained by the adhesive. Therefore, although the horizontal opening injection molding machine is used at the trial production stage, it has not been put into practical use for mass production.

Therefore, using a vertically opening type injection molding machine, the insert film is placed horizontally on the cavity surface of the lower mold, the molding material is injected onto the back side of the insert film, and the integrally molded product is placed in the lower mold. It is also possible to push it upward with an ejector part and take it out from the cavity surface of the lower mold.

However, in this case, the tip of the ejector turbine of the ejector section may come into contact with the exposed surface, which is the design surface of the insert film, damaging the exposed surface of the insert film, or the molten molding material injected from the side of the cavity. It has invaded between the exposed surface of the insert film and the cavity surface and adhered to the exposed surface, thus hindering its practical use.

An object of the present invention is to provide a film insert injection molding machine that solves the above-mentioned conventional problems.

[Means for Solving the Problems] The film insert injection molding machine of the present invention includes an upper mold forming a cavity on a mating surface in a horizontal position, and a lower mold having a mounting surface on which an insert film is placed in the cavity. The upper mold includes a gate portion for injecting the molding material toward the back side of the insert film placed on the placement surface of the cavity, and a gate portion for opening the molded product integrally molded with the insert film. The molded product is characterized by having a holding mechanism that holds the molded product on the upper mold, and an ejector portion that pushes out the molded product held on the upper mold downward to release the molded product from being held by the holding mechanism.

The upper mold and the lower mold can be relatively movable, with one of them being a fixed mold and the other being a movable mold.

The lower mold serves as a mounting surface on which the insert film of the cavity formed on the mating surface in the horizontal position is placed together with the upper mold.
For example, a flat shape can be used.

The upper mold has a gate part, a holding mechanism, and a part of the injector.

The gate part injects the molten molding material toward the back side of the insert film placed on the mounting surface of the cavity.For example, a cold runner one-type upper die tunnel gate or a hot runner one-type tunnel gate is used. A passage through which the molding material flows may be used, such as a gate connected to a portion of the hot runner of the upper mold.

The holding mechanism holds the molded product integrally molded with the insert film using the molding material injected into the cavity from the gate part until the upper mold and the lower mold reach a preset mold opening position when the mold is opened. , acts to hold the upper mold. This holding mechanism is, for example, formed in the upper mold and constituted by a passageway in which the tunnel gate part of the upper mold with one cold runner type is bent, or the holding mechanism is formed in the upper mold with a one-way hot runner type, and the upper mold has a bent passage. - Consisting of a structure connected to a passage, the molded product is hardened by injecting the molten molding material into the cavity, and after being injected, a part of the molding material remaining in the passage of the upper mold maintains a constant hardness. A part of the injected molding material is connected to the molded part to form a connecting part, and a Z pin whose tip part that contacts the cavity of the ejector turbine has a so-called Z-shaped gap. It is possible to use a device that fills the gap in the Z-shape integrally with the product and connects and holds the Z-bin and a part of the molded product.

The ejector part pushes out the molded product held in the upper mold by the holding mechanism downward, and forcibly releases the holding of the holding mechanism. For example, the ejector parts are each held by an upper mold and are moved up and down so that their tips come into contact with the molding material filled on the side opposite to the surface of the insert film that serves as the design display surface, that is, on the back side of the insert film. an ejector turbine held movably; an ejector plate held movably up and down on the back surface opposite to the cavity surface of the upper mold; a stopper member that limits the movable range of the ejector plate; and one end connected to the ejector plate. The ejector plate may be configured with a plurality of ejector turbines that push the product downward at the other end thereof, and a biasing member that biases the ejector plate downward when the upper mold moves upward. A plurality of eject turbines can be used. Moreover, it is preferable that at least one of the plurality of ejector turbines has a Z-shaped notch at its tip and forms a part of the above-mentioned holding mechanism. In addition, the biasing member biases the ejector plate in a direction to push out the ejector turbine until the upper mold and the lower mold are separated by a certain distance when the mold is opened, but when the movement distance exceeds the above range, the ejector plate It is possible to use a structure in which the biasing force can be released. In addition, by using the biasing member, a sufficient mold opening distance can be maintained between the upper mold and the lower mold, making it easier to set the insert film on the mounting surface, and making it easier to take out the molded product and maintain the cavity surface. This has the effect of making it easier.

[Operations and Effects] According to the film insert injection molding machine of the present invention, the upper mold forming the cavity on the mating surface in the horizontal position and the lower mold having the mounting surface on which the insert film is placed in the cavity are in an open state. , the insert film is set horizontally with the front side, which is the design display side, placed on the above-mentioned placement surface and the back side facing upward.

After the upper mold and the lower mold are closed, the molding material is injected from the gate of the upper mold toward the back side of the insert film. The insert film is pressed against the mounting surface from the back side by the pressure of the injection of the molding material, and is securely held at a predetermined set position. Therefore, the molding material is filled into the cavity space on the back side of the insert film without entering between the insert film and the mounting surface, that is, on the exposed surface of the insert film, and is integrated with the insert film without staining the design display surface. The molded article is molded. Then, when opening the mold, the transition occurs,
When the molded product reaches a preset mold opening position while being held in the upper mold by the holding mechanism, the ejector portion held in the upper mold is integrally formed on the back surface of the insert film of the molded product. The holding mechanism releases the holding mechanism by contacting the held part and pushing it downward. As a result, the insert film inserted into the lower end of the molded product is pushed out downward by the ejector from the state where it is held in the upper mold, since the exposed surface that is the design display surface is located on the opposite side from the ejector. The design display surface will not be scratched when

It is possible to eliminate the problem of setting the insert film vertically on the setting surface of the cavity, which is the case when a horizontally opening injection molding machine is used.

[Example 1] The film insert injection molding machine of Example 1 of the present invention is of a vertical opening type, and as shown in FIGS. 1 and 2, a lower mold 1 which is a fixed mold and a It consists of a cold runner type upper mold 2 which closes and opens the mold relative to the lower mold 1. When the lower mold 1 and the upper mold 2 are in the mold closed state, a lower cavity surface 40 and an upper cavity surface 42 provided on the horizontally positioned lower mating surface 3a and upper mating surface 3b respectively form a cavity in the shape of the product to be molded. It forms the property 4.

The lower mold 1 has a flat mounting surface 41 on which the insert film 8 is mounted on the lower cavity surface 40 . The lower die 1 also has an engaging portion 10 that engages a biasing member 227, which will be described later.
An insertion hole 10 having a diameter of 1.a, a wall surface 202a forming a horizontal passage 202 of the tunnel gate section 20, and a concave wall surface 201a forming a nozzle touch section 201 are provided. The lower end of the lower mold 1 is connected to and held by a lower mold mounting plate 11.

The upper mold 2 is of a cold runner type and has a holding mechanism 21.
, the ejector section 22 , and the upper cavity surface 42
have. Further, the upper end portion of the upper mold 2 is connected and held via a spacer member 23 to an upper mold mounting plate 24 which is mounted so as to be interlocked with a movable part of a mold clamping device of the same rank. As a result, the upper mold 2 is attached to the upper mold mounting plate 2 when the mold is closed and when the mold is opened.
4, the upper mating surface 3b can be moved in the direction of coming into contact with and separating from the lower mating surface 3a of the lower mold 1.

The tunnel gate section 20 is located on the mounting surface 4 of the cavity 4.
A passage is formed for injecting the molten molding material toward the back surface 81 side of the insert film 8 placed on the insert film 1 . This tunnel gate part 20 is a horizontal passage 20 communicating with the nozzle touch part 201 when the mold is closed (see FIG. 1).
2, an inclined passage 204 that extends obliquely upward from the horizontal passage 202 via the reservoir 203 and forms a constriction part, and a vertical passage 20 that intersects the inclined passage 204 at an acute angle and opens into the upper cavity surface 42. has been done.

The holding structure 21 is a molded product 4 formed in the cavity 4.
A is held in a bonded state to the upper cavity surface 42 of the upper mold 2 until it reaches a preset mold opening position, and is made up of a first holding part 210 and a second holding part 211. The first holding part 210 includes an inclined passage 204 and a vertical passage 20 that form the tunnel gate part 20 when the mold is closed.
When the molding material is filled into the cavity 4 and the approximately inverted V-shaped space formed by the passages 204 and 20
A rod-shaped body (consisting of a molding material>48) that exists before and after the intersection position P1 with 5, is filled in the cavity 4, and is integrated with the molded product 4A after molding. is a Z-shaped notch P2 located on the upper cavity surface 42 of the upper mold 2 when the mold is closed and connected to the cavity 4.
a second engine turbine 225 having a
The molded product 4A in the cavity 4 is filled with the molded product 4A.

The ejector part 22 is attached to the upper mold 2 by the holding mechanism 21.
The molded product 4A held by the molded product 4A is pushed downward to release the held state, and the first and second ejector plates 221. 222, a stopper member 223 that limits the movable range of the first and second ejector plates 221, 222, and the first ejector plate 22.
1, and the other end pushes out the molded product 4A downward. The upper die 2 is connected to the upper mold 2 when it moves up when the mold is opened. When the first and second positions are reached,
It consists of a biasing member 277 that biases the ejector plates 221 and 222 downward.

The stopper member 223 is of a hanging type, and one end engages with the upper mold mounting plate 24, and the other end engages with the second end when the mold is opened.
It engages with the ejector plate 222 to regulate the amount of extrusion of each ejector turbine 224, 225, 226.

The first ejector turbine 224 has one end fixed to the first ejector plate 221 and the other end fixed to the upper mold 2.
It can move in the vertical passage 205 of the tunnel gate part 20, and has a length such that it is located above the crossing position P1 when the mold is closed, and below the crossing position P1 when the ejector part 22 is activated when the mold is opened.

The second ejector turbine 225 has one end fixed to the first ejector plate 221, and the other end movable toward and away from the upper cavity surface 42 of the upper mold 2. It has a length that projects from the surface 42 toward the molded product 4A side. Further, the other end of the second extractor turbine 225 has a Z-shaped notch P2, and is located on the same surface as the upper cavity surface 42 when the mold is closed.

The third ejector turbine 226 has one end fixed to the first ejector plate 221, and the other end is movable in and out of the horizontal passage 202 side of the tunnel gate section 20, and forms the horizontal passage 202 when the mold is closed. It is located on the same plane as the wall surface 202b, and has a length that protrudes from the wall surface 202b when the ejector section 22 is activated when the mold is opened.

The biasing member 227 has one end connected to the first ejector plate 2.
21, and the other end passes through the upper mold 2 and extends in the direction of the lower mold 1. Further, the other end of the biasing member 227 is connected to the vertically divided groove 22
7a, a tip engaging portion 227b is formed which is elastically deformed in the radial direction and whose outer diameter can be contracted and expanded from the contracted state.

Next, a case will be described in which a molded product 4A having an insert film 8 is molded using the insert film injection molding machine of Example 1 formed as described above.

According to the film insert injection molding machine of this embodiment, when the lower mold 1 and the upper mold 2 are in the open state (see FIG. 3), the mounting surface 41 of the lower cavity surface 40 of the lower mold 1 is On the other hand, the insert film 8 is placed in a horizontal state with the exposed surface 80 side serving as the design display surface and the back surface 81 side facing upward. Then, as shown in FIG. 1, the lower mold 1 and the upper mold 2 are closed. At this time, the tip engaging portion 227b of the biasing member 227 is connected to the engaging hole 1 of the lower die 1.
It is inserted into 0. Thereafter, molding material is indexed and filled from the tunnel gate portion 20 of the upper die 2 toward the back surface 81 side of the insert film 8. At this time, the insert film 8 is pressed tightly against the mounting surface 41 from the back surface 81 side by the injection pressure of the molding material, and is securely held at a predetermined set position, and the molding material is pushed onto the exposed surface 80 side. The cavity 4 is filled without entering or going around. Then, a molded product 4A integrated with the insert film 8 is molded. Next, when the mold is opened, it moves to the upper mold 2.
moves upward and away from the lower mold 1. At this time, upper mold 2
When the molded product 4A is adhered and held on the upper cavity surface 42 by the holding mechanism 21 and reaches the preset mold opening position, the tip engaging portion 227b of the biasing member 227 of the ejector portion 22 is activated. It engages with the engagement portion 10a of the engagement hole 10 of the lower mold 1. In this state, as the upper die 2 further moves upward, the biasing member 227 biases the first ejector plate 221, which is engaged with one end thereof, downward. Then, the first and second engine turbines 224.22
5 and the third engine turbine 226 are interlocked, and the other end (tip) of the first engine turbine 224 is connected to the tunnel gate 2.
The other end (tip) of the second engine turbine 225 is moved downward from the crossing position P1 of the
The other end (tip) of the third engine turbine 226 protrudes from the upper die wall surface 202b (see FIG. 2).

As a result, the first engine turbine 224 has a rod-shaped molding material 4a in the vertical passage 205 of the tunnel gate section 20.
The second edger turbine 225 pushes out the molded product 4A by contacting the part formed integrally with the back surface 81 of the insert film 8, and the third edger turbine 226 pushes out the part formed integrally with the back surface 81 of the insert film 8 of the molded product 4A. The molding material (equivalent) in the passage 202 is pushed out and the holding mechanism 21 is forcibly moved.
Release the holding of molded product 4A by. Then, as shown in FIG. 2, the extruded molded product 4A is separated from the Z-shaped notch P2 of the second extractor turbine 255 and taken out.

Therefore, according to the injection molding machine of Example 1,
When the molded product 4A is pushed out downward by the ejector section 22 from the state held by the upper die 2, the molded product 4
The insert film 8 inserted into the lower end side of A has an exposed surface 80 serving as a design display surface facing the ejector section 2.
Since it is located on the opposite side from 2, the design display surface will not be scratched.

Furthermore, as in the case of using a conventional side-opening injection molding machine, it is possible to eliminate the problems that occur when the insert film 8 is set vertically on the set surface of the cavity, and the defective rate can be greatly reduced. .

Also, when opening the mold of the injection molding machine of this example,
The biasing member 227 has a first biasing member that engages the tip engaging portion 277b.
Since the downward movement of the ejector plate 221 is restricted by the stopper member 223, the ejector plate 221 moves upward together with the upper mold 2, and as shown in FIG.
b is the lower mold], and the upper mold 2 and the lower mold 1 can obtain a wide mold opening stroke L.

Therefore, it is easy to set the insert film 8 on the mounting surface 41 of the lower cavity surface 42 of the lower mold 1, and when taking out the molded product 4A to the outside, the insert film 8 can be easily set on the lower cavity surface 40 and the upper Workability such as cleaning the cavity surface 42 is improved.

(Example 2) A film insert injection molding machine of Example 2 will be explained using FIG. 5.

The film insert injection molding machine of Example 2 uses a hot runner one-type upper mold 2A, and instead of using the approximately inverted ■-shaped tunnel gate part 20 of Example 1, a hot runner having a nozzle touch part 200 is used. A runner nozzle 20a and a hot runner part 2 having a generally inverted shape that communicates the hot runner nozzle 20a and the cavity 4.
0b and a gate portion 20C, and the hot runner portion 20b and gate portion 20G form a first holding portion 210a.
is configured. This first holding part 210a is the first holding part 210a according to the first embodiment.
This corresponds to the first holding part 210 of the holding mechanism 21 of FIG. Furthermore, instead of the stopper member 223 of the first embodiment that restricts the movement of the first and second ejector plates 221 and 222 due to the urging action of the urging member 227, an ejector spring 223a is used between the first ejector plate 221 and the upper mold 2. It is placed between. First engine turbine 22
4a has a length that allows the other end to move in and out of the upper cavity surface 42 of the upper mold 2A, and protrudes from the cavity surface 42 toward the molded product 4A when the ejector portion 22a is activated when the mold is opened. In addition, the third engine turbine 226
The length a is movable toward and away from the upper mating surface 3b of the upper mold 2A, and has a length that projects from the upper mating surface 3b toward the molded product 4A when the ejector portion 22a is activated when the mold is opened.

The configuration other than the above is the same as that of the first embodiment.

According to the film insert injection molding machine of Example 2, when the lower mold 1 and the upper mold 2A are closed, the molten molding material is injected into the cavity 4 from the hot runner nozzle 20a, the hot runner part 20b, and the gate part 20G, Filled. When the mold is opened after molding the molded product 4A, the first ejector turbine 224a of the ejector portion 22a
The other end (tip) contacts and pushes out the molding material (circuit) integrally formed on the back surface 81 of the insert film 8 of the molded product 4A, and the gate portion 20C1 of the first holding mechanism 210a
'Separate from the hardened molding material (circle).Other operations are the same as in Example 2.

In the case of the second embodiment, the tip end engaging portion 227b of the biasing member 227 is closer to the engaging portion 10a of the engaging hole 10 of the lower mold 1.
When released, the first and second ejector plates 221.2 are moved by the elastic return force of the ejector spring 223a.
22, first, second, and third engine turbines 224a, 2
25.226a, the biasing member 227 can be returned to its old position.

Further, the embodiments of the present invention are not limited to the above embodiments 1 and 2, and for example, a hot runner may be used in the film insert injection molding machine system shown in FIG. can.

[Brief explanation of the drawing]

Figures 1 to 3 relate to the film insert injection molding machine in Example 1, with Figure 1 being a sectional view showing the mold in a closed state, Figure 2 being a sectional view showing the mold in the middle of opening, and Figure 3 being a sectional view showing the mold in the middle of opening. FIG. 3 is a cross-sectional view showing the state after the mold is opened. FIG. 4 is a partially enlarged cross-sectional view of FIG. 1. FIG. 5 is a sectional view showing a mold closed state of the film insert injection molding machine in Example 2. 1... Lower die 2... Upper die 3a... Lower mating surface 3b... Upper mating surface 4... Cavity
20... Tunnel gate part 21... Holding mechanism
22... Ejector part 40... Lower cavity surface

Claims (1)

[Claims] (1) It consists of an upper mold that forms a cavity on a mating surface in a horizontal position, and a lower mold that has a mounting surface on which the insert film is placed in the cavity, and the upper mold is placed on the mounting surface of the cavity. a gate portion for injecting a molding material toward the back side of the placed insert film; a holding mechanism for holding a molded product integrally molded with the insert film on the upper mold when the mold is opened; 1. A film insert injection molding machine comprising: an ejector section that pushes out the molded product downward to release the holding mechanism.