JP2534174Y2 - Low pressure mold - Google Patents

Description

[Detailed description of the invention]

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a low-pressure mold in a resin transfer molding method.

[0002]

2. Description of the Related Art A conventional low pressure molding method will be described with reference to the drawings. FIG. 10 is a cross-sectional view showing a state in which the molded article 1 is molded between the upper mold 3 and the lower mold 4. In this case, if the molded article boss or stud bolt 2 to 1 is provided, these bosses or studs 2 moldings
If it is provided at an acute angle α with respect to the direction of the
When the molded article 1 is released from the molding die 3 after molding, the boss or the stud bolt 2 interferes with the upper molding die 2, so that the molding cannot be released.

For this reason, conventionally, as shown in FIG. 11, the boss and the stat bolt 2 formed on the molded article 1 have been formed in such a manner that the shapes of the bosses and the stud bolts 2 are parallel to each other in the releasing direction.

[0004]

As described above, in a conventional molded product having a boss or a stud bolt,
There was no freedom in the direction of the product shape or the boss, stud bolt, etc., and the product structure was controlled, so that there was a problem that a reasonable structure could not be adopted. In addition, the cost is increased due to an increase in weight and wasted use of materials. Furthermore, such a shape also causes defects such as sink marks on the product surface.

The present invention has been made in view of such a point, and has a boss portion or a stud bolt portion which can be removed even if there is some interference in the removal direction of the molded product. An object is to provide a modified mold mechanism used in the manufacture of articles.

[0006]

SUMMARY OF THE INVENTION The present invention is directed to a molding die for manufacturing a molded article having a projection such as a boss or a stud bolt . Removal direction of molded product from wall
This is a low-pressure molding die which is formed in parallel or with a draft angle, and which is formed by providing a rubber molded body between the hole and the projection.

[0007]

[Action] The inner wall surface of the hole in which the projecting part such as the boss or stud bolt of the molded product enters is parallel to the mold release direction.
It is formed with a margin as a draft or with a rubber molded body having elasticity between this hole and a projection such as a boss or a stud bolt. The cut part can be eliminated.

[0008]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS An embodiment of the present invention will be described below with reference to the drawings. FIG. 1 is a sectional view showing an upper mold and a lower mold in a low-pressure molding method. That is, the lower molding die 4 has a cavity surface 4 ′ conforming to the shape of the molded product on the upper surface similarly to the conventional molding die.
Is formed. On the other hand, the upper mold 3 to be clamped with this
a is a boss or stud bolt provided on the molded product.
The holes 5 are formed at the corresponding positions of the gate 2 . This hole 5
Shape they become smaller conical shape of the bottom, the inner wall surface formed
Be parallel to or perpendicular to the mold release direction of the molded product.
The angle of the mold side of the inner wall surface to the plane is obtuse, that is,
It is formed so as to have a draft angle. The hole 5 is formed by providing a conical rubber molded body 6. At the time of demolding after molding, the rubber molded body 6 is demolded together with the molded product, and then removed from the molded product. Then, the mold is installed and used again. The rubber molded body 6 is provided on the upper molding die 3a to be installed.
The diameter of the hole 5 is slightly larger than the shape of the hole 5 so that the resin injected by the range transfer molding method does not enter, and does not fall out of the upper molding die 3a.

Therefore, the boss shape or the
Dodge shape causes interference with mold in the direction of mold release
Even if it is in a shape, it can be released together with the rubber molded product, and a rational design of the molded product is possible. This is effective in reducing the weight of the molded product and limiting the amount of material used .

Next, a modified example will be described with reference to FIGS. When the interference angle α increases,
The shape of the rubber molding 6 is changed, and the hole 5 of the upper molding die 3a is changed.
It is possible to cope with it more easily. That is, as shown in FIG. 2, the shape of the rubber molded body 6 is formed so that the tip is at an angle β from the height a. The angle β is provided to prevent falling off and to make it easy to remove. If the height a is small in size even if it interferes, it is impossible to shrink it because it is made of rubber from the upper mold 3a. This is because it is possible to extract it.

In FIG. 3, a similar effect can be obtained by forming the rubber molded body 6b into a tapered spheroidal shape. As described above, by utilizing the elasticity of the rubber molded body, the molding die is fitted into the hole and the mold is released.

Next, a second embodiment will be described with reference to FIG. In this example, an insert is fixed to a rubber molded body provided in the hole 5 of the upper molding die 3a by using a projection such as a stud or a boss. That is, the hole 7 corresponding to the shape of the stat bolt or the boss is formed in the center of the bottom surface of the rubber molded body 6c. The hole 7 is used to hold a stat bolt or boss 2 inserted into a molded product to perform molding.

FIG. 5 shows a modification of FIG. 4, in which a projection 9 is formed at the center of the bottom surface of the rubber molded body 6d. The protrusion 9 is inserted into a hole of an insert 8 to be inserted into a molded product, and is held.

Next, based on FIG . 6 , FIG. 7 and FIG.
An embodiment will be described. FIG. 6 shows the upper mold 3b and the lower mold 4
3 shows a state in which the molded article 10 is molded. Removing the inner wall surface of the hole 5a formed in the upper mold 3b from the mold
To the plane parallel to the direction or perpendicular to the direction in which the molded product is released.
The inner wall surface is formed so that the angle on the mold side constituting the inner wall surface is obtuse, that is, a draft angle . 7 and 8 are enlarged views of a portion A in FIG.
And the arrow P indicates the direction in which the molded article is released from the mold. As shown in FIGS. 7 and 8, a rubber molded body 6e conforming to the shape is put into the widened gap between the boss 10a of the molded product 10 and the hole 5a of the upper molding die 3b. The rubber molded body 6e is provided with a protrusion 11 so that the rubber molded body 6e can be inserted into a hole of the upper molding die 3b and fixed.

Therefore, the rubber material forming member 6e makes it easy to remove the mold. In the case of FIG. 7, the rubber material forming member 6e remains in the upper molding die 3b, and in the case of FIG. The material forming body 6 e is extracted together with the molded article 10.

In the case shown in FIG. 8, the rubber molding 6e is fixed to the upper molding die 3b by the protrusion 1 of the rubber molding 6e.
It can be easily performed by utilizing the elasticity of 1.
Demolding is easy. When this fixing is performed with an inelastic body, it is necessary to add a troublesome structure such as screwing,
Since the protrusion 11 is integrally formed with the rubber molded body 6e, attachment and detachment becomes easy.

As a modified example, the rubber molded body 6f is shown in FIG.
As shown in (1), the molded product 10 can be molded so as to cover the entire boss 10a, and the fixing to the upper molding die 3b can be facilitated.

[0018]

As described above, according to the low-pressure forming mold structure of the present invention, the removal of the mold is extremely facilitated by providing the rubber-like molded body of rubber or the like at the undercut portion of the mold. In addition, the fabrication of the mold is facilitated, and a rational design is possible. In addition, excellent effects are achieved, such as reduction in the weight of the product and reduction in the amount of material used.

[Brief description of the drawings]

FIG. 1 is a cross-sectional view of a low-pressure mold showing an embodiment of the present invention.

FIG. 2 is a cross-sectional view of a modified low-pressure mold.

FIG. 3 is a sectional view of a low-pressure molding die according to another modification.

FIG. 4 is a sectional view of a low-pressure molding die according to a second embodiment.

FIG. 5 is a sectional view of a low-pressure molding die according to a modification of the second embodiment.

FIG. 6 is a cross-sectional view illustrating a low-pressure molding die according to a third embodiment.

FIG. 7 is a cross-sectional view illustrating a low-pressure molding die according to a third embodiment.

FIG. 8 is a cross-sectional view showing a low-pressure molding die according to a modification of the third embodiment.

FIG. 9 is a cross-sectional view showing a low-pressure molding die according to another modification of the third embodiment.

FIG. 10 is a cross-sectional view for explaining a conventional low-pressure molding die.

FIG. 11 is a cross-sectional view showing a conventional low-pressure molding die.

[Explanation of symbols]

DESCRIPTION OF SYMBOLS 1 Molded product 2 Boss or stud bolt 3, 3a, 3b Upper mold 4 Lower mold 5 Hole 6, 6a, 6b, 6c, 6d, 6e, 6f Rubber molding

Claims (1)

(57) [Scope of request for utility model registration] 1. A molding die for manufacturing a molded product having a projection such as a boss or a stud bolt, wherein an inner wall surface of a hole in which the projection of the molding such as a boss or a stud bolt is inserted is removed from a molding die. A low-pressure molding die formed by forming a rubber-like molded body between the hole and the projecting portion .