JPH0512016Y2 - - Google Patents

Description

[Detailed description of the invention] [Industrial application field] This invention relates to molds, and in particular improves the quality of molded products and facilitates the work of releasing the product from the mold. This relates to a mold that can be used to create a mold.

[Prior art and its problems]

Conventionally, a mold for rubber products, which is designed to produce a plurality of molded products at once, is constructed as shown in FIG.

That is, grooves 12, 12 are formed at a predetermined interval in the center of the upper surface of the main body 11 of the mold, and a plurality of grooves (three rows in the drawing) are formed at a predetermined interval between the grooves 12, 12. 21 (in 7 rows) O-ring grooves 13, 13, . ...and horizontal groove 15,1
5.... is drilled.

When molding an O-ring using the mold configured as described above, first, as shown in Fig. 7, 20 pieces of dough are placed in the center part, and then pressure is applied. When this is done, the dough spreads as shown in Figure 8. In this case, if there is not enough dough 20 or if the dough 20 is pressed when it is misaligned, the dough 20 will not cover the four corners of the mold, resulting in insufficient fill. However, when pressurizing, thinning 21 occurs as shown in FIG. 9 taken along line A-A in FIG.
There is a problem that this thin burr 21 may turn over and adhere to the product.
When a silicon material is used as the burr 0, pressure is applied to the burrs located in the grooves 12, 12, which are burr pools, as shown in FIG. 10, which is a view taken along line B-B in FIG. Since the material is not easily vulcanized, a portion of the dough 20 becomes unvulcanized, and the adhesion to the mold becomes strong, resulting in a problem in that it takes time and effort to release the product from the mold.

This invention solves the problems of the conventional methods as described above, and can prevent the formation of thin burrs during pressurization, and can sufficiently cover the four corners of the mold. It is an object of the present invention to provide a mold that can facilitate mold release work by preventing the formation of unvulcanized parts and preventing adhesion to the mold.

[Means for solving problems]

In order to achieve the above purpose, a plurality of vertical grooves and horizontal grooves are provided on the upper surface of the mold body to form a lattice pattern, and each of the central portions of the mold body surrounded by the vertical grooves and horizontal grooves is A groove for a molded product is formed, a plurality of grooves for a molded product are provided, and longitudinal grooves and horizontal grooves are further formed in the peripheral portion of the mold body so that the interval between the grooves is narrower than in the central portion of the mold body. As a result, the vertical grooves and horizontal grooves at the four corners of the upper surface of the mold body form a dense lattice structure.

[Effect]

When a molded product is obtained using a mold configured as described above, the grooves are densely provided on the periphery of the molded product, so that weak thin burrs are not formed. There is no risk of adhesion to the product, and since there is no burr accumulation, sufficient pressure can be applied during vulcanization, and furthermore, the fabric can be sufficiently spread through the vertical and horizontal grooves at the four corners.

〔Example〕

Embodiments of this invention shown in the drawings will be described below.

A mold according to this invention is shown in FIGS. 1 to 3, and a plurality of molds (in the drawing, 3 columns, 7 rows, and 21
) O-ring grooves 3, 3, ... are formed,
Vertical grooves 4, 4, and horizontal grooves 5, each having a V-shaped cross section, surround the O-ring grooves 3, 3, .
A plurality of vertical grooves 4 and horizontal grooves 5 are formed in a grid pattern at the four corners of the mold body 1 where the O-ring grooves 3, 3, . . . are formed. There is.

In addition, the vertical grooves 4, 4, ... and the horizontal grooves 5,
5, . . . are not V-shaped but may have other shapes.

The state seen along line A-A in FIG. 1 is as shown in FIG. 2, and the state seen along line A-A in FIG.
The state seen along the line is as shown in FIG. 3, that is, in FIG. 2, the vertical groove 4 and the groove 3 of the O-ring are formed in the mold body in a positional relationship that corresponds to each other. However, in FIG. 3, the lateral grooves 5 and the O-ring grooves 3, which are formed in a mutually coincident positional relationship on each mold body, are shown, respectively.

Therefore, unlike conventional molds, the four peripheral edges of the O-ring grooves 3, 3, . . . have a plurality of grooves 4, 4, . . . , 5, 5, .
... are further drilled, and they form a grid pattern at the four corners of the mold body 1, which is denser than at the center.

When performing molding work using the mold configured as described above, first, the O-ring groove 3,
3. A vertical groove 4 with a V-shaped cross section surrounding...
4, . . . and horizontal grooves 5, 5, . At this time, a plurality of vertical grooves 4, 4, . . . and horizontal grooves 5, 5, . , when the dough 6 spreads, the dough flowing in the horizontal direction has horizontal grooves 5,
5. At the same time as it flows inside, this horizontal groove 5,5,
It also flows into the vertical grooves 4, 4, which intersect with...
Conversely, the fabric 6 flowing in the vertical direction has vertical grooves 4, 4,
...At the same time as it flows inside, these vertical grooves 4, 4...
The flow also flows into the horizontal grooves 5, 5, ... which intersect with the vertical grooves 4, 4, ... and the horizontal grooves 5, 5, ...
There is enough fabric 6 in the four corners where ... intersect each other
wraps around and prevents underfill defects from occurring.

Furthermore, like the conventional one, there are grooves 1 for burr accumulation on both sides of O-ring grooves 3, 3, .
2 and 12 are not provided, and instead of the vertical grooves 4,
4. Since a plurality of . . . are provided, uncured burrs of the silicon material can be prevented.

That is, the conventional burr trap grooves 12, 12 must be filled with the fabric 20 in order to be vulcanized, but the yield is still poor.
By providing a plurality of vertical grooves 4, 4, . . . as burr traps, the surface pressure increases and vulcanization occurs under pressure, thereby eliminating the generation of unvulcanized burrs.

Regarding the O-ring manufactured using the above mold, the grooves 3, 3, . . . formed in the mold in which the O-ring is to be molded are polished, and The surface of the O-ring formed by grooves 3, 3, etc. has a similarly clean finish, and the surface is coated to reduce torque during use, but the surface is clean. Therefore, even if a coating was applied, the coating would peel off quickly, making it impossible to maintain low torque during use, and therefore causing wear in a short period of time.However, the O-ring groove formed in the mold By shooting the surface of the O-ring 7 with glass beads and thereby making the surface of the product rough (uneven), the coating 8 is applied to the surface of the O-ring 7, which is the product, as shown in Fig. 4. The coating 8 bites into the recess formed on the outer circumferential surface of the O-ring 7, and the coating 8 can fully exert its effect without peeling off, and low torque can be maintained for a long time.

Then, the O-ring 7 formed as described above
When comparing the relationship between the O-ring and the O-ring coated without forming recesses on the surface in terms of the relationship between the standing time and the rotational torque, as shown in Fig. 5, there is a significant difference in the change in the rotational torque with respect to the standing time. I was able to confirm something. In this case, both are coated NBR rubber Hs70, and in FIG. 5, the O-ring with a recess formed on its surface is an O-ring without a recess.

[Effect of idea]

As mentioned above, this invention has a plurality of small grooves bored outside the groove for the molded product, which eliminates the problem of thin burrs forming and adhering to the molded product as in the conventional method. In addition, the multiple grooves drilled on the outside of the molded product grooves intersect in a grid pattern at the four corners, so the dough flows into the grooves that are perpendicular to each other, allowing the dough to wrap around the molded product at the four corners. This method has excellent effects such as improving the efficiency of molding operations since there is no risk of underfill defects and there is no need to remove thinning burrs.

[Brief explanation of drawings]

Figure 1 is a plan view showing the mold according to this invention;
Figure 2 is a view taken along line A-A in Figure 1;
The figure is a view taken along line B-B in Figure 1, Figure 4 is a cross-sectional view of a coated O-ring, and Figure 5 is a diagram showing the relationship between the standing time and rotational torque of an example of a molded product. Figure 6 is a plan view of a conventional mold,
Figure 7 is a diagram showing the state in which the fabric is positioned before being pressed;
Figure 8 is a diagram showing the state in which the fabric is positioned and pressed;
Figure 9 is a view taken along line A-A in Figure 6.
FIG. 0 is a view taken along line B--B in FIG. 6. 1, 11... Mold body, 3, 13... Groove of molded product, 4, 14... Vertical groove, 5, 15... Horizontal groove, 6,
20...Dough, 7...O-ring, 8...Coating, 12...Groove, 21...Thin.

Claims (1)

[Scope of utility model registration request] A plurality of vertical grooves 4 and horizontal grooves 5 are provided on the upper surface of the mold body 1 to form a lattice-like shape, and a groove 3 for the molded product is located in the area surrounded by the vertical grooves 4 and the horizontal grooves 5 in the center of the upper surface. A plurality of vertical grooves 4 and horizontal grooves 5 are further formed on the peripheral edge of the mold body 1, and the interval between the grooves is narrower than that in the center, so that the vertical grooves 4 and the horizontal grooves 5 at the four corners of the upper surface are closely spaced. A mold that is characterized by its grid-like shape.