JP2001300973A - Molding method - Google Patents

Abstract

(57) [Problem] To integrally form a resin molded product and a thin functional layer made of a material having poor fluidity by using a mold. A part of a mold surface of a mold is retracted, and a molding material having poor fluidity is injected into a space formed between a predetermined surface of a resin molded article and the mold surface. Molded product 10
4 is compression molded. Since the space 12 can be formed widely, a predetermined amount can be easily injected even with a hard-to-flow molding material, and the thin functional layer is integrally formed on the surface of the resin molded article 104 by compression molding. It can be welded and joined.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a method of molding a resin molded product having a thin functional layer integrally, and more particularly, to a molding method capable of integrally welding and joining a thin functional layer that cannot be molded by injection molding to a resin molded product. About.

[0002]

2. Description of the Related Art FIG. 10 shows a mounting structure of a window glass of an automobile. The window glass 100 is adhered to a mounting portion 101 of the vehicle body via a urethane sealer 102, and a glass run 103 mounted on an edge keeps the inside of the vehicle airtight. A stopper 104 is previously adhered to a predetermined position of the window glass 100.
Are locked in the locking holes 105 of the mounting portion 101, so that the window glass 100 is temporarily fixed until the urethane sealer 102 is hardened.

The stopper 104 is attached to the window glass 1
In order to adhere to the adhesive layer, a urethane-based adhesive or a double-sided tape has been used. However, in the method using an adhesive, there is a problem that it takes a long time until the adhesive is cured and the bonding strength is developed. Disposal is also a problem.

[0004] Therefore, WO 98/15401 discloses that a stopper 104 is attached to a window glass 100 by a vibration welding method.
A method of joining the two is disclosed. By joining by the vibration welding method in this way, the time required for the joining strength to be developed is short, the joining can be fully automated, and dust on the release paper does not occur.

[0005]

SUMMARY OF THE INVENTION Window glass 10
It has been found that flexible PVC is particularly preferable as a material that can strongly join the stopper 104 and the stopper 104 and can be joined by the vibration welding method. Therefore, if an adhesive layer made of soft PVC is formed on the joining surface of the stopper, and it is placed at a predetermined position on the surface of the window glass 100 and subjected to vibration welding, the stopper 10 can be quickly and firmly joined to the window glass 100. Can be.

In order to form an adhesive layer made of soft PVC on the joining surface of the stopper, there is a method of forming an adhesive layer by attaching a tape-shaped soft PVC formed separately to the stopper 104. However, this method has a problem that the number of steps for separately manufacturing a tape-shaped soft PVC is large.

Therefore, it has been considered that the adhesive layer is formed by molding and is integrated with a predetermined surface of the stopper 104. The stopper 104 is generally manufactured by injection molding from PBT or the like. Therefore, if the adhesive layer is also formed by injection molding, the mold can be shared, and it is very convenient because it is integrally joined to the surface of the stopper 104 by welding.

[0008] The adhesive layer made of soft PVC is 0.3 to
It is necessary to be formed as thin as 0.5 mm, and if it is thicker than this, the bonding strength is reduced due to internal destruction of the adhesive layer. However, since soft PVC is hard to flow, it is difficult to use a soft PVC.
It is difficult to inject and fill in a cavity having a thickness of 3 to 0.5 mm, and problems such as poor filling cannot be avoided.

The present invention has been made in view of such circumstances, and an object of the present invention is to integrally form a resin molded product and a thin functional layer made of a material having poor fluidity by using a mold. I do.

[0010]

A feature of the molding method of the present invention that solves the above-mentioned problems is that a first step of arranging a resin molded product in a cavity of a mold and a step of retracting a part of the mold surface of the mold are performed. After injecting a hard-to-flow molding material into a space formed between the predetermined surface of the resin molded product and the mold surface, compression molding is performed between the mold surface and the predetermined surface of the resin molded product to form a resin molded product. And a second step of integrally welding and bonding a thin functional layer made of a hard-to-flow molding material to a predetermined surface.

[0011]

DESCRIPTION OF THE PREFERRED EMBODIMENTS In a first step, a resin molded product is placed in a cavity of a mold. In this step, a separately formed resin molded product may be arranged in a mold, but it is desirable to form the resin molded product in the mold. This makes the first
The step and the second step can be performed continuously, and the productivity is significantly improved. In order to form a resin molded product in a mold, injection molding, injection compression molding, or the like can be performed. Various molding materials are selected according to the purpose.
For example, when forming the above-mentioned stopper, it can be formed by injection molding or injection compression molding from a thermoplastic resin such as PBT.

In the second step, a part of the mold surface of the mold is retracted after the first step. Then, a hard-to-flow molding material is injected into a space formed between the predetermined surface of the resin molded product and the mold surface. Since this space is not particularly limited and can have a large volume, a predetermined amount can be easily injected into the space even with a hard-to-flow molding material. Examples of this hard-to-flow molding material include the above-mentioned flexible PVC which is difficult to fill in a narrow cavity.

After a predetermined amount of the hard-flowing molding material is injected, compression molding is performed between the mold surface and the predetermined surface of the resin molded product by advancing the mold surface. Since compression molding is used, a thin functional layer can be easily molded even with a molding material having poor fluidity. And since the molding material with low fluidity is pressed against a predetermined surface of the resin molded product in a molten fluid state,
By selecting a molding material that can be welded to the resin molded product, a thin functional layer integrally welded and bonded to a predetermined surface of the resin molded product can be formed. A predetermined amount of the hard-flowing molding material may be injected, and the compression speed can be set variously. Therefore, molding using various molding materials is possible, and various functions according to the molding material can be imparted to the thin functional layer.

In the second molding step, the mold surface is driven forward, so that the injection port (gate) of the hard-to-flow molding material can be closed by the slide die driven forward. Therefore, the burrs can be cut and closed by a slide type, and automatic deburring can be performed.

Further, in the molding method of the present invention, the mold surface is moved forward.
It is configured to be able to retreat. Therefore, if the size of the thin functional layer is smaller than the size of the resin molded product, the resin molded product can be released from the mold surface by further advancing the mold surface when the mold is opened after molding. .

Although the first step and the second step may be performed by using separate molds, it is preferable that the first and second steps be performed by the same mold. In this case, the gate for forming the resin molded article and the gate for forming the thin functional layer may be shared, or separate gates may be formed and used.

The thin functional layer is not limited to the above-mentioned adhesive layer, but may be a layer having various functions. Further, it can be formed to have a thickness corresponding to various functions.

[0018]

The present invention will be described below in detail with reference to examples. In the following embodiment, the stopper described in the related art is formed together with the adhesive layer.

(Embodiment 1) As shown in FIG. 1, first, the slide die 1 is retracted to open the gate 10, and a predetermined amount of the molten PBT resin 3 is injected from the gate 10 into the cavity 11. Next, the slide mold 1 is advanced to perform compression molding, and FIG.
The stopper 104 is formed as shown in FIG.

Next, the burr 106 in the gate 10 is removed, and the slide mold 1 is retracted again, and a relatively wide cavity 12 is provided between the stopper 104 and the mold surface of the slide mold 1 as shown in FIG. To form Then, a predetermined amount of the molten resin of the soft PVC 4 is injected into the cavity 12 from the gate 10. Since the cavity 12 is relatively wide, even a hard-flowing soft PVC can be easily injected and injected.

Next, the slide mold 1 is advanced to compress and mold the soft PVC 4 in the cavity 12 and is welded to the bottom surface of the stopper 104 as shown in FIG.
m of the adhesive layer 200 is formed. And after release, burr 20
1 is cut off to obtain the stopper 104 in which the adhesive layer 200 is integrally welded and joined.

Therefore, according to the molding method of this embodiment,
Since the stopper 104 having the thin adhesive layer 200 can be formed by one mold, the number of steps can be significantly reduced as compared with the related art, and an inexpensive stopper can be obtained.

(Embodiment 2) However, in the molding method of Embodiment 1 described above, a step of cutting off the burr 201 after the molding is required, and post-processing of the burr 106 and the burr 201 is required, so that the number of steps is large. There is a problem that.

In this embodiment, two gates, one forming the stopper 104 and the other forming the adhesive layer 200, are used.
There are different types of gates.

As shown in FIG. 5, the mold used in this embodiment has a first gate 21 and a second gate 22, which can be opened and closed by a first slide mold 13 and a second slide mold 14, respectively. Has become. A heater (not shown) is arranged around the first gate 21 and the second gate 22, and the PBT resin 3 supplied into the first gate 21 and the soft PVC 4 supplied into the second gate 22 are always melted. Maintained in state. Note that FIG.
FIG. 3 shows an equivalent view of a state viewed from a lateral direction.

In molding, as shown in FIG. 5, first, the second slide 22 is moved to the forward position, the second gate 22 is closed, and the first slide die 13 is retracted to form the first gate 21.
open. Then, the PBT resin 3 is injected and filled into the cavity 11, and then the first slide mold 13 is advanced to perform compression molding to form the stopper 104. At this time, the first gate 21 is closed by the first slide mold 13 at the same time, so that no burr is generated on the stopper 104.

Next, as shown in FIG.
4 is retracted to open the second gate 22, and the stopper 104
A relatively wide cavity 12 is formed between the bottom surface of the second mold 14 and the mold surface of the second slide mold 14. Then, a predetermined amount of soft PVC 4 is injected and injected from the second gate 4 into the cavity 12.
Since the cavity 12 is relatively wide, the flowable soft PV
Even C4 can be easily injected and injected.

Subsequently, as shown in FIG. 8, the second slide die 14 is advanced to compress and mold the soft PVC 4 in the cavity 12 and is integrally welded and bonded to the bottom surface of the stopper 104 to have a thickness of 0.5 mm. The layer 200 is formed. At this time,
At the same time, the second gate 22 is closed by the second slide die 14, so that no burrs are formed on the adhesive layer 200.

At the time of opening the mold after the molded product is cooled and solidified,
As shown in FIG. 9, the second slide die 10 is further advanced. As a result, the stopper 104 is released from the first slide mold 13 and can be easily released.

Therefore, according to the molding method of this embodiment,
A stopper 1 having a thin adhesive layer 200 as in the first embodiment.
04 can be formed with one mold, and since no burr is generated, the number of steps can be greatly reduced.

[0031]

That is, according to the molding method of the present invention, a resin molded product having a thin functional layer integrally can be formed by one mold, so that the man-hour is reduced and the resin molded product is inexpensive. be able to.

[Brief description of the drawings]

FIG. 1 is a cross-sectional view showing the inside of a mold immediately before molding a resin molded product in one embodiment of the present invention.

FIG. 2 is a cross-sectional view showing the inside of a mold immediately after molding a resin molded product in one embodiment of the present invention.

FIG. 3 is a sectional view showing the inside of a mold immediately before forming a thin functional layer in one embodiment of the present invention.

FIG. 4 is a cross-sectional view showing the inside of a mold immediately after forming a thin functional layer in one embodiment of the present invention.

FIG. 5 is a sectional view showing the inside of a mold immediately before molding a resin molded product in a second embodiment of the present invention.

FIG. 6 is a sectional view showing the inside of a mold immediately after molding a resin molded product in a second embodiment of the present invention.

FIG. 7 is a sectional view showing the inside of a mold immediately before forming a thin functional layer in a second embodiment of the present invention.

FIG. 8 is a cross-sectional view showing the inside of a mold immediately after forming a thin functional layer in a second embodiment of the present invention.

FIG. 9 is a sectional view showing the inside of a mold when a molded product is released from a mold according to a second embodiment of the present invention.

FIG. 10 is a sectional view showing an attachment structure of an end portion of a window glass of an automobile.

[Explanation of symbols]

1: Slide type 3: PBT resin
4: Soft PVC 104: Stopper (resin molded product) 200: Adhesive layer (thin functional layer)

──────────────────────────────────────────────────続 き Continued on the front page (51) Int.Cl. ⁷ Identification symbol FI Theme coat ゛ (Reference) B29L 31:30 B60J 1/18 G

Claims (2)

[Claims] 1. A first step of disposing a resin molded product in a cavity of a mold, wherein a part of a mold surface of the mold is retracted and formed between a predetermined surface of the resin molded product and the mold surface. After injecting a molding material having poor fluidity into the space, the compression molding is performed between the mold surface and the predetermined surface of the resin molded product, and the molding material having poor fluidity is formed on the predetermined surface of the resin molded product. And a second step of integrally welding and joining the thin functional layers made of the following. 2. The resin molded product is a resin component fixed to a window glass of an automobile, and an adhesive layer made of soft PVC is integrally joined to a predetermined surface of the resin component by compression molding. The molding method according to claim 1.