JP2600426Y2 - Mold - Google Patents

Description

[Detailed description of the invention]

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to improvement of a mold.
Things .

[0002]

2. Description of the Related Art In molding a molded article shown in FIG. 5, a molding die shown in FIG. 6 is conventionally used.

[0003] moldings 5 is a plug tube gasket for sealing between the sheet cylinder head cover and the plug tube, the mounting ring portion 21, an annular lip supporting portion 2
2 and an annular lip portion 23 are integrally formed using a rubber-like elastic material as a molding material, a reinforcing ring 24 is embedded in the mounting ring portion 21, and an annular seal portion 25 is provided on the inner peripheral surface of the lip portion 23. The portion 23 has a structure in which an annular spring 26 is embedded.

The molding die shown in FIG. 6 is for compression molding the molded product shown in FIG. 5, and has a plurality of divided dies 41, 42, 43, and a cavity surrounded by these divided dies 41, 42, 43. 44. Cavity 44, mounting ring portion 21 by filling the molding material into here, the lip supporting part 22 and the lip portion 23 be one integrally molded, prior to filling the molding material into the cavity 44, the cavity 44, the reinforcing ring 24 and the spring 26 are set as insert parts. At a predetermined position of the cavity 44, a reinforcing ring setting portion 45 for setting the reinforcing ring 24 is provided.
And a spring set portion 46 for setting the spring 26. An annular wall surface rising from the outer peripheral edge of the spring set portion 46 (wall portion forming the outer peripheral surface of the lip portion 23) 4 of the inner wall of the cavity 44
7 shows that the portion (outer peripheral surface of the lip portion 23) 27 corresponding to the wall surface 47 of the molded product is straight in the axial direction because the lip support portion 22 and the lip portion 23 thermally contract after molding. , And has a tapered surface that opens outward. The figure shows this taper by θ.

[0005]

However, the prior art described above does not provide the cavity 4 in the process of molding a molded article.
When the molding material is filled in the spring set part 4,
6 is lifted from the spring set portion 46 by the flow of the molding material, and the lip portion 23 is solidified in this state. Therefore, the defective product embedded in the position where the spring 26 is deviated from the position where it should be. There is a problem that is molded.

[0006]

SUMMARY OF THE INVENTION In view of the above, the present invention has been devised in order to solve the above-mentioned problems in the prior art. So that the inner peripheral surface of the lip part
And a spring on the lip.
Molded products such as plug tube gaskets embedded with
A mold, wherein the lip is provided on an inner wall of the cavity.
A first wall forming the outer peripheral surface of the lip,
A second wall surface forming an end surface and an inner peripheral surface of the lip portion
Form the third wall surface to be formed and the inner peripheral surface of the lip support.
A fourth wall, which is formed, and the third wall and the fourth
At the boundary between the fourth wall and the flow during injection of the molding material.
The spring by the first wall and the second wall
The injection gate is opened at a position where the injection gate is pressed against the corner .

According to a second aspect of the present invention, there is provided a molding die for forming a molded product such as a plug tube gasket having a seal portion provided on an inner peripheral surface of a lip portion connected to a lip support portion and a spring embedded in the lip portion. A first wall surface forming an outer peripheral surface of the lip portion, a second wall surface forming a distal end surface of the lip portion, and a third wall forming an inner peripheral surface of the lip portion on an inner wall of the cavity. And a fourth wall forming an inner peripheral surface of the lip support portion, a spring set portion is provided at a corner between the first wall surface and the second wall surface, and the third wall surface and the third wall surface are provided. An axially straight fifth wall is provided at the boundary of the fourth wall, and an injection gate is opened on the fifth wall.

[0008]

If opening the injection gate to the position specified by [action] claim 1, it is embedded in the lip of the plug tube gasketing DOO
The springs that flow during molding material injection
Since it is pressed against the corner between the first wall surface and the second wall surface of the tee, it does not float. According to the molding die of the second aspect, the spring is pressed against the corners of the first wall surface and the second wall surface provided with the spring set portion by the flow at the time of injection of the molding material, so that the spring does not float. The fifth wall surface forms an axially straight portion at the boundary between the inner peripheral surface of the lip portion and the inner peripheral surface of the lip support portion of the molded product according to the second aspect. If burrs are formed on the product at the mark of the injection gate, the burrs are formed on the straight portion in the axial direction toward the inner circumference.

[0009]

BRIEF DESCRIPTION OF THE DRAWINGS FIG.

As shown in FIG. 1, the molding die is for injection molding or transfer molding of a plug tube gasket, and has a plurality of split dies 1, 2, 3, and 4.
It has a cavity 5 for integrally molding the mounting ring 21, the lip support 22, and the lip 23, which are surrounded by the split dies 1, 2, 3, and 4. A reinforcing ring set portion 6 for setting a reinforcing ring 24 at a predetermined position of the cavity 5, a first wall surface 8 forming an outer peripheral surface of a lip portion 23 on an inner wall of the cavity 5,
A second wall surface 9 forming the distal end surface of the lip portion 23, a third wall surface 10 forming the inner peripheral surface of the lip portion 23, and a fourth wall surface 11 forming the inner peripheral surface of the lip support portion 22; , A spring set 7 is provided at a corner between the first wall surface 8 and the second wall surface 9, and the third wall surface 10 and the fourth wall surface 1 are provided.
A fifth wall 12 which is straight in the axial direction is provided at the boundary of 1, and an injection gate 13 is opened in the fifth wall 12. The wall surfaces 8, 9, 10, 11, 12 are each annular, and the first wall surface 8 is a tapered surface that opens outward as in the prior art.

When a plug tube gasket is formed by the mold having the above structure, the reinforcing ring 24 is set in the reinforcing ring set 6 and the spring 26 is set in the spring set 7 and the mold is clamped. 2, the spring 26 is pressed against the corners of the first wall surface 8 and the second wall surface 9 provided with the spring set portion 7 by the flow at the time of injection of the molding material, as shown in FIG. Become. Therefore, it is possible to prevent the spring 26 from being lifted up by being pressed by the molding material, and to form a good product in which the spring 26 is buried in a proper position.

FIG. 3 shows a cross section of the plug tube gasket formed by the above-mentioned mold. The inner peripheral surface of the lip portion 23 and the inner peripheral surface of the lip support portion 22 are different from the plug tube gasket of FIG. The fifth embodiment is different from the first embodiment in that a portion (cylindrical surface) 28 that is straight in the axial direction is formed by the fifth wall surface 12 at the boundary. The reason why the fifth straight wall surface 12 which is straight in the axial direction is provided in the mold and the straight portion 28 in the axial direction is formed in the gasket is as follows. That is, as shown in FIG.
Even if burrs 29 are formed on the gasket at the mark of the injection gate 13 (parting surface), a portion 28 which is straight in the axial direction is formed.
Is parallel to the direction in which the gasket is inserted into the plug tube 14 (indicated by an arrow), and the burrs 29 facing inward fall down to the lip 23 side, so that the burrs 29 may bite into the plug tube 14. This is because the burr 29 does not interfere.

[0013]

[0014]

[Effects of the Invention] The present invention has the following effects. Sand
First, according to the mold of the present invention having the above-described structure, the mold is embedded in the lip portion of the plug tube gasket.
The spring that is installed depends on the flow when the molding material is injected.
Press on the corner between the first and second walls of the cavity
The spring is pressed by the molding compound
Floating in the cavity can be prevented. I
As a result, the spring is precisely
Molding good plug tube gaskets buried
be able to. Also, according to the mold by 請 Motomeko 2,
In order that the spring is Ru pressed against the corner portion of the first wall surface and a second wall provided with a spring set portion by the flow during the injection of molding material, without floating up by being pushed by the molding material, the spring is originally Non-defective products buried at desired positions can be molded. Therefore since these, as configured buried position of Luz pulling put the molded article, the performance as expected in the molded article can be exhibited. Also, in addition to this, according to the mold of claim 2, in order to decide to providing a straight fifth wall in the axial direction to form a straight portion in the axial direction of the molded article, even if burrs Even if it is formed, the burr does not bite into the plug tube, and does not affect the mountability.

[Brief description of the drawings]

FIG. 1 is a sectional view of a main part of a molding die according to an embodiment of the present invention.

FIG. 2 is a partially enlarged view of FIG. 1;

FIG. 3 is a sectional view of a main part of a plug tube gasket.

FIG. 4 is an explanatory view showing a method of mounting the gasket.

FIG. 5 is a sectional view of a main part of a plug tube gasket.

FIG. 6 is a sectional view of a main part of a molding die according to a conventional example.

[Explanation of symbols]

 1, 2, 3, 4 Split type 5 Cavity 6 Reinforcement ring set part 7 Spring set part 8 First wall 9 Second wall 10 Third wall 11 Fourth wall 12 Fifth wall 13 Injection gate 14 Plug tube Reference Signs List 21 mounting ring part 22 lip support part 23 lip part 24 reinforcing ring 25 seal part 26 spring (insert part) 27 outer peripheral surface of lip part 28 axial straight part 29 burr

──────────────────────────────────────────────────続 き Continued on the front page (58) Field surveyed (Int. Cl. ⁶ , DB name) B29C 45/00-45/84 B29C 33/00-33/76

Claims (2)

(57) [Scope of request for utility model registration] (1)A lip connected to the lip support (22)
The seal portion (25) is provided on the inner peripheral surface of the portion (23).
A spring (26) is embedded in the lip (23).
For forming molded products such as plug tube gaskets
A mold, wherein the lip portion is provided on an inner wall of the cavity (5).
A first wall surface (8) forming an outer peripheral surface of (23);
Second wall surface (9) forming the tip surface of the lip (23)
And a third wall forming an inner peripheral surface of the lip portion (23)
Surface (10) and the inner peripheral surface of the lip support (22).
A fourth wall (11) to be formed, Of the third wall surface (10) and the fourth wall surface (11)
Boundary, and the flow during injection of the molding material
A ring (26) between the first wall (8) and the second wall;
The injection gate is located at the position where it is pressed against the corner with the surface (9).
(13) A mold having an opening. 2. A plug tube gasket or the like in which a seal (25) is provided on the inner peripheral surface of a lip (23) connected to the lip support (22) and a spring (26) is embedded in the lip (23). A molding die for molding a molded product, wherein a first wall surface (8) forming an outer peripheral surface of the lip portion (23) and a tip end surface of the lip portion (23) are formed on an inner wall of a cavity (5). Second wall to be formed (9)
And a third wall surface (10) forming an inner peripheral surface of the lip portion (23) and a fourth wall surface (11) forming an inner peripheral surface of the lip support portion (22). A spring set (7) is provided at a corner between the first wall surface (8) and the second wall surface (9), and an axial direction is provided at a boundary between the third wall surface (10) and the fourth wall surface (11). A mold having a straight fifth wall (12) provided thereon, and an injection gate (13) opened in said fifth wall (12).