JPH047934Y2 - - Google Patents

Description

[Detailed Description of the Invention] (Industrial Application Field) The present invention relates to an insert molding die for integrally injection molding a synthetic resin molded part to an insert.

(Prior Art) Tube containers for storing paste-like substances such as toothpaste, mustard, wasabi, etc. are formed by integrally molding a container mouth part to one end of a tube that has been previously formed into a cylindrical shape. .

FIG. 4 is a sectional view showing an insert molding die for forming this type of tube container or the like.

Numeral 10 is a core type, and a core 14 is erected in a central recess 12 to regulate the inner shape of the tube container to be obtained.

16 is a cavity type, and the core 14 of the core type 10
A cavity portion into which the tip portion loosely fits is provided in a recessed manner, and the cavity surface of the cavity portion and the tip surface of the core define a cavity 18 for molding the container mouth portion. That is, the cavity surface forms the outer shape of the container mouth, and the core tip surface forms the inner shape of the container mouth.

The core 14 of the core mold 10 is enclosed by a side wall 20, and is configured to receive mold clamping force from the end surface of the side wall 20, that is, the parting surface with the cavity mold 16.

First, with the mold open, the mold 1
The tube 22 was inserted into the cavity 6 or the core 14 of the core mold 10, and then the mold was closed and resin was injected into the cavity 18, thereby integrally molding the container mouth at the end of the tube 22. Tube containers can be obtained.

(Problems to be solved by the invention) However, the conventional insert molding die described above has the following problems.

In other words, if the insert tube 22 is soft, such as a toothpaste tube, the edge of the tube may get caught on the rim of the cavity and become deformed, as shown in Figure 4. If the molten resin is injected into the cavity as it is, the tube end is not introduced into the cavity and a gap is created between the cavity mold 16 and the core mold 10, so the molten resin flows into the core outside the cavity 18. It may also be injected into the recess 12 of the mold 10.

However, even if the above-mentioned inconvenience occurs, conventionally it cannot be confirmed until the mold is opened after molding, and if the tube 22 is long, the core mold 10 is deep, so the injected material may not be injected into the core mold 10. There was also the problem that it was difficult to remove the ivy resin.

Therefore, the present invention was devised to solve the above-mentioned problems, and its purpose is to make it possible to easily check the deformation of inserts such as tubes from the outside, and to prevent the deformation of inserts such as tubes from occurring in the case that they occur inside the core-shaped recess. To provide an insert molding die that can be easily removed even if resin is injected.

(Means for Solving the Problems) The present invention aimed at solving the above problems consists of a cavity mold and a core mold, and the core mold stands upright in the mold opening/closing direction and inserts are fitted therein. In a molding die comprising a core member and a side wall that stands up on the side of the core member and comes into contact with the mold cavity to receive mold clamping force when the mold is closed, the side wall of the core mold is fitted with the core member. In order to observe the state of the inserted insert, it is characterized by having a transparent window that is not blocked by a shielding material such as glass.

(Embodiment) A preferred embodiment of the present invention will be described in detail below based on the accompanying drawings.

In FIGS. 1 and 2, 30 is a core type, has a rectangular planar shape, and has a recess 32 opening on the top surface. Three cores 36 are erected on the inner bottom surface of the recess 32 at regular intervals such that their tips protrude upward from the upper surface of the side wall 34 .
The core 36 defines the internal shape of the tube to be obtained.

Reference numeral 38 denotes a cavity mold, and the parting surface thereof is recessed with a cavity portion into which the tips of the cores 36 of the core mold fit loosely when the cavity mold 38 is closed with respect to the core mold 30. The cavity surface 38 of the cavity portion and the core end surface 40 define a cavity 42 for molding the container opening. That is, the cavity surface 38 forms the outer shape of the container mouth, and the core tip surface 40 forms the inner shape of the container mouth.

44 is a hot runner communicating with the cavity 42.

A feature of the present invention is that the both side walls 34 of the core mold 30 are provided with transparent parts that are not shielded by a shielding material such as glass so that the state of the tube container fitted in the core 36 can be observed. This is because a hole-shaped window portion 46 is provided.

As is clear from FIG. 1 and FIG.
They are opened individually. Further, the inner bottom surface of each window portion 46 coincides with the inner bottom surface of the recess 32 of the core mold 30.

Next, the molding procedure will be explained.

First, when the mold is opened, the tube 4 is attached to the core 36.
8, and then close the mold. As a result, the tip of the tube protruding from the body of the core 36 enters the cavity 42 and is bent slightly inward along the cavity surface 38. By bending the tip of the tube slightly inward, the joint area between the tube 48 and the container opening increases, and the joint strength is increased.

After the mold is closed, the cavity mold 38 and the core mold 30 are subjected to a predetermined mold clamping force by a mold opening/closing device (not shown), and this mold clamping force is received by the cavity mold and the core mold side wall.

Next, molten resin is injected and filled into the cavity 42 via a hot runner 44 from an injection device (not shown).

By opening the mold and taking it out after cooling, it is possible to obtain a tube container in which the container opening is integrally formed at the end of the tube.

When closing the mold, the tube 48 is inserted as shown in Figure 4.
If deformation occurs, the condition can be easily confirmed through the window 46. Therefore, in this case, the molding process is interrupted, the mold is opened, the deformed tube is replaced, and molding is started again. Such deformation of the tube 48 is likely to occur at the beginning of molding before the molding reaches a steady state, but the condition of the tube 48 should be checked through the window 46 with particular care at this early stage of the start of molding.

Furthermore, in the unlikely event that injection is performed while the tube 48 is still deformed, the resin may leak into the recess 3 of the core mold 30.
Even if the resin adheres to the inside of the recess 32, it can be easily removed from the window 46, which is not shielded by a shielding material such as glass and is formed in line with the inner bottom surface of the recess 32. .

In the above embodiment, a three-cavity mold is shown, but it is needless to say that the mold is not limited to this. Further, the window portion may be formed into one large window, or may be opened up to the parting surface of the core mold 30 as shown in FIG. Further, the inner bottom surface of the window does not necessarily have to match the inner bottom surface of the recess of the core mold 30; it is more preferable to form it one step lower than the inner bottom surface of the recess, or it may be formed slightly higher than the inner bottom surface of the recess.

Furthermore, although the above embodiments have been described using the case of molding a tube container as an example, it goes without saying that the present invention can be broadly applied to molds for integrally molding a mouth portion, a lid, etc. to an insert.

Furthermore, although not shown, if an optical sensor or the like is provided in the window section to recognize the deformation of the insert as an image, confirmation of the quality of the insert can be easily automated.

(Effects of the invention) As described above, according to the invention, the condition of the insert during mold clamping can be checked from the outside, so any abnormality in the insert can be known before the injection process, and if any abnormality is found, the insert can be replaced. You can perform processing such as

Therefore, it is possible not only to prevent the production of defective products as much as possible, but also to prevent an accident in which resin is accidentally injected into the recess of the core mold.
Furthermore, even if resin should be injected into the core-shaped recess, the adhering resin can be taken out extremely easily from the window.

Furthermore, since the condition of each part such as the core can be seen from the outside, adjustments and corrections at the start of molding can be easily performed, and various other effects are achieved.

[Brief explanation of the drawing]

The drawings show an embodiment of the insert molding die according to the present invention, with FIG. 1 being a longitudinal sectional view thereof and FIG. 2 being a front view thereof. FIG. 3 is a front view showing another embodiment. FIG. 4 shows a longitudinal sectional view of a conventional insert molding die. 10...Core mold, 12...Central recess, 14...
Core, 16...Cavity type, 18...Cavity,
20... Side wall, 22... Tube, 30... Core mold, 32... Recess, 34... Side wall, 36... Core, 38... Cavity type, 40... Core tip surface, 4
2...Cavity, 44...Hot runner, 4
6...Madobe, 48...Tube.

Claims (1)

[Claims for Utility Model Registration] Consists of a cavity mold and a core mold. In a mold having a side wall that comes into contact with the cavity mold and receives mold clamping force when closed, a shielding material such as glass is installed on the side wall of the core mold so that the state of the insert fitted into the core member can be observed. An insert molding mold characterized by having a transparent window portion that is not blocked by a material.