JPS595560Y2 - injection mold - Google Patents

Description

[Detailed explanation of the idea] This invention relates to an injection mold.

For example, a beer bottle container is usually provided with a grip part for holding the hand, and this grip part has a large roundness on the underside to make it easier to hold the container. is considered preferable.

However, the conventional injection molds used to mold the containers described above are
As shown in the figure, a cavity C is formed by closing a fixed mold 1, a male mold 2, and a split mold 3.

Furthermore, the tip of a movable member 4 provided in the split mold 3 so as to be able to advance and retreat diagonally downward in a direction away from the side wall of the male mold 2 comes into contact with the side wall of the male mold 2, and the molded product The grip portion H is rounded.

When manufacturing a beer bottle container using such an injection mold, the molded product obtained by injecting the molding material into the cavity C formed inside and solidifying it is placed in a fixed mold. This is done by separating the male mold 2 and the split mold 3 from the mold 1.

That is, the male mold 2 is moved upward and the fixed mold 1 is
At the same time, the split mold 3 is moved away from the fixed mold 1 and the male mold 2.

At this time, the movable member 4 provided on the split mold 3 retreats obliquely downward in a direction away from the side wall of the male mold 2, damaging the roundness of the lower side of the gripping portion H of the molded product. Take out the molded product so that it does not come out.

However, in the injection mold as described above, the movable member 4 for forming a roundness on the lower side of the gripping part H is configured to retreat diagonally downward. If it is desired to form a large roundness in which the tangent line is higher than the direction of advance and retreat of the movable member 4, an undercut will occur, and as a result, the movable member 4 will cause a galling phenomenon at the rounded part of the gripping portion H. If you force this to leave,
There is a drawback that the rounded portion may be damaged.

This idea was made in view of the above circumstances, and the movable member that forms the undercut part of the surface facing downward, such as the lower side of the grip of a beer bottle container, is spaced directly below the undercut part. The purpose of the present invention is to provide an injection mold that can easily form a rounded portion of a desired size in the undercut portion.

Hereinafter, one embodiment of this invention will be described in detail based on FIGS. 3 and 4.

In the figure, 10 is a fixed type, and a male type 11 is attached to this fixed type 10.
and a split mold 12 are arranged so as to open and close the mold by coming into contact with and separating them, so that the lower surface of the male mold 11 comes into contact with the upper surface of the fixed mold 10, and the lower surface and side surfaces of the split mold 12 contact the upper surface of the fixed mold 10. Cavities C1 and C2 are formed when the upper surface of the fixed mold 10 and the side surface of the male mold 11 are brought into contact.

A window insert 19 is coupled to the split mold 12, and a substantially triangular prism-shaped cavity 13 is formed from the lower part of the cavity C2 (that is, the cavity forming the gripping part H of the molded product). It is formed.

A movable member 14 for forming a rounded portion on the lower side of the grip portion H is disposed in this gap portion 13.

The movable member 14 is mounted so as to be reciprocally movable along an angular pin 15 disposed on the split mold 12 within the cavity 13 and inclined obliquely downward toward the side wall of the male mold 11. There is.

That is, the angular pin 1 is attached to the movable member 14.
5 fitting holes 16 are formed.

The window insert 19 also has a hole 19a into which the angular pin 15 is fitted, an insertion hole 19b into which a rotating body 20 (to be described later) is inserted, and a hole 19b which is provided in the insertion hole 19b and allows the rotating body 20 to rotate. A movably pivoted shaft 21 is provided.

Further, a coil spring 18 is attached to the angular pin 15 between the fitting hole 16 of the angular pin 15 and the hole 19a of the window insert 19 and concentrically with the angular pin 15. The movable member 14 is pushed diagonally downward by the coiled spring 1B.

The rotating body 20 is rotatably attached to the window insert 19 via a shaft 21.

One end of this rotating body 20 is inserted into a cavity 17 formed in the movable member 14, and is in contact with one side P of the cavity 17.

Further, the other end of the rotating body 20 is in contact with one end of the actuating member 22 .

This actuating member 22 is connected to a circular hole 2 formed in the split mold 12.
3 and is configured to reciprocate along this circular hole 23, and the other end is in contact with the male die 11.

The rotating body 20, the shaft 21. The operating member 22 and the circular hole 23 constitute a return device.

Note that reference number 24 is a stopper member for stopping the movement of the movable member 14.

Next, the operation of the mold configured as described above will be explained.

First, as shown in FIG. 3, a cavity C1 is formed by closing the fixed mold 10, the male mold 11, and the split mold 12.
, C2 and solidify the molding material.

At this time, the movable member 14 forms a downward undercut portion of the grip portion H while being sandwiched between the fixed positions of the male mold 11 and the split mold 12.

Thereafter, when the molded product is taken out from the cavities C1 and C2, the male mold 11 is first moved upward and separated from the fixed mold 10 by a drive device (not shown).

As a result, the male die 11 is also separated from the upper end of the actuating member 22.

Thereafter, the male mold 11 is further moved upward, and the split mold 12 is moved to the upper right in the figure in a direction away from the side wall of the male mold 11 by a predetermined link device or drive device (not shown). Then, the movable member 14 is moved obliquely downward along the angular pin 15 by the coil spring 1B.

That is, the movable member 14 does not move in the moving direction of the split mold 12, but shifts downward while its left side is pressed against the male mold 11.

In other words, it moves directly below the gripping portion H of the molded product.

At this time, the rotating body 20 is pressed by one side P of the cavity 17 of the movable member 14 and is rotated counterclockwise in FIG.
This pushes the actuating member 22 upward.

Then, the movement of the movable member 14 is stopped by a stopper member 24.

After this, as shown in FIG. 4, when the male mold 11 and the split mold 12 are further moved, the movable member 14 moves together with the split mold 12 to the upper right in the figure. , and are separated without damaging the molded product, so that the molded product can be removed.

In addition, when closing the male mold 11 and the split mold 12 to the fixed mold 10, the operation opposite to the above may be performed.

In this case, the male die 11 hits the upper end of the actuating member 22 and pushes it downward, and the rotating body 20 rotates clockwise in the figure, tilting the movable member 14 to the right along the angular pin 15 and returning it upward. .

Therefore, by closing the male mold 11 and the split mold 12, the return device returns the movable member 14 to its original state as shown in FIG.

As explained above, according to the injection mold according to the invention, the movable member that forms the undercut part of the downward facing surface, such as the lower side of the grip of a beer bottle container, is Since it is configured to be spaced directly below the undercut portion, a rounded portion of a desired size can be easily formed in the undercut portion.

[Brief explanation of the drawing]

Fig. 1 is a sectional view of the main part of a conventional injection mold, Fig. 2 is a sectional view showing the mold in an open state, and Fig. 3 is a sectional view of the main part showing an embodiment of the invention. FIG. 4 is a sectional view showing a state in which the mold of this embodiment is opened. 10...Fixed type, 11...Male type, 12
...Split mold, 14...Movable member, 15.
...Angular pin (guide member), 20...
...Rotating body, 22...Operating member.

Claims (1)

[Scope of utility model registration request] Between a fixed mold, a male mold that is located above the fixed mold and opens the mold upward, and a split mold that is located above the fixed mold and tilts away from the male mold and opens the mold upward. , a downwardly directed undercut portion of the molded article by means of a movable member that forms a cavity into which the molding material is injected and that is provided on the male mold and the mold half to be sandwiched between fixed positions in each of the mold parts; In an injection mold for molding, a movable member is provided at a fixed position of the split mold so as to be movable downward from the fixed position toward the male mold; The movable member is provided with a spring that biases the movable member diagonally downward so that the movable member is tilted and moved downward while being pressed toward the male mold side when opening. An injection molding die comprising a return device that returns the movable member diagonally upward so as to return the movable member between the fixed positions at the time of the injection molding.