JPH0611151Y2 - Mold for molding - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION [Industrial field of application] The present invention relates to a mold for molding resin products and the like.

[Prior Art] Conventionally, when a plurality of molded products such as resin products are simultaneously molded by a set of molding dies, the pressure applied to each molding cavity during mold clamping varies. However, there was a problem that burrs were generated on some molded products. for that reason,
Various molding dies capable of molding without burrs have been proposed.

For example, the pot type mold shown in FIGS. 3 and 4 is provided with a lower mold 21, a middle mold 22 and an upper mold 23 which are provided so as to be able to come into contact with and separate from each other, and the lower mold 21 and the middle mold 22 are provided with both 21 and 22, respectively. A plurality of holes 24 are formed therethrough. Then, a pair of lower mold core 26 and middle mold core 27 forming a cavity 25 for molding are incorporated in the plurality of holes 24, respectively. In addition, in correspondence with the upper surface of each medium-sized core 27, the medium-sized 2
A concave pot 28 into which the upper mold 23 is fitted is formed in 2. Further, the upper mold 23 is formed with an introduction path 29 for injecting a molding material.

Therefore, the molding material injected from the introduction path 29 is used as the medium mold 22.
Each of the cavities 25 is filled with the molding material by introducing the molding material into the pot 28 and compressing the molding material with the middle mold 22 by the clamping force of the upper mold 23. At this time, the pressure applied to the upper surface of each medium-sized core 27 is
The cores 26 and 27 are evenly applied to the cores 27, respectively, and the cores 26 and 27 are individually clamped with a uniform pressure to tightly seal the mold surfaces, thus preventing the occurrence of burrs.

Further, the spring type mold shown in FIGS. 5 and 6 is provided with a lower mold 31, a middle mold 32 and an upper mold 33 which are provided so as to be able to come into contact with and separate from each other, and a plurality of holes 34 penetrating the lower mold 31 and the middle mold 32. Has a pair of lower mold cores 36 that form a cavity 35 for molding.
And the medium core 37 are incorporated. Further, compression springs 38 are individually attached to the lower surface of each lower die core 36. Further, an introduction path 39 for press-fitting the molding material is formed in the upper die 33, and the upper die 33 and the middle die 3
A runner 40 for guiding the molding material press-fitted from the introduction path 39 to each cavity 35 is formed between the two.

Therefore, the molding material press-fitted from the introduction path 39 by the injection pressure is filled in each cavity 35 via the runner 40. At this time, the injection pressure of the molding material is evenly applied to each cavity 35 via the runner 40. Then, the injection pressure presses the medium core 37 against the lower core 36,
Due to the repulsive force of the spring 38, the cores 37 and 36 are individually clamped with a uniform pressure, the mold surfaces are tightly sealed, and burrs are prevented from occurring.

[Problems to be Solved by the Invention] However, in the pot-type mold, there is a problem that the ratio of the molding material remaining in the pot 28 becomes large and the yield of the molded product becomes very poor. That is, the fourth
As shown in the figure, the molding material remains on the entire portion of the circular pot 28. Therefore, in extreme cases,
In some cases, the amount of the material remaining in the pot 28 may be larger than that of the material forming the molded product.

On the other hand, in the spring-type mold, unlike the pot-type mold, there is no problem in the yield of molded products, but the lower mold 3
Not only does the thickness of No. 1 increase by the amount of assembling of the spring 38, the machining cost and weight increase, but also the assembling structure of the spring 38 becomes complicated and there is a problem in terms of maintenance.

The present invention has been made in view of the above-described circumstances, and an object thereof is to simultaneously mold a plurality of molded products with a set of molding dies, and therefore to reduce the yield of the molded products. It is an object of the present invention to provide a molding die that does not have a metal mold structure and can be simplified.

[Means for Solving the Problems] In order to achieve the above object, in the present invention, a lower mold, a middle mold that can be contacted and separated from the lower mold, an upper mold that can be contacted and separated from the middle mold, and a middle mold are provided. A plurality of assembled molding cores, a molding cavity formed between each core and the lower mold, and an end surface of each core and a facing surface of the upper mold for filling a molding material. And a runner formed between the upper mold and the middle mold for introducing the molding material into the filling recess. .

[Operation] Therefore, in a state where the lower mold, the middle mold and the upper mold are clamped together, the molding material introduced through the runner by a predetermined injection pressure is formed between the end surface of each core and the facing surface of the upper mold. The filled concave portion is filled, and further the cavity is filled. At this time, the injection pressure of the molding material is evenly applied to the end surface of each core through the molding material filled in each filling recess, and each core is pressed toward the lower mold side. Therefore, the cores forming the cavities and the lower mold are individually clamped with an equal pressure, the mold surfaces are tightly sealed, and burrs are prevented from occurring.

[Embodiment] An embodiment embodying the present invention will be described below in detail with reference to the drawings.

FIG. 1 shows a vertical cross section of a main part of a molding die for simultaneously molding a plurality of rubber products.

This molding die is a lower die 1, which is provided so as to be able to come into contact with and separate from each other,
A middle mold 2 and an upper mold 3 are provided, and the lower mold 1 and the middle mold 2 are both
A plurality of holes 4 passing through 2 are formed. Then, a pair of lower mold core 6 and middle mold core 7 forming a cavity 5 for molding are incorporated in the plurality of holes 4, respectively.

Further, between the upper end surface of each middle mold core 7 and the facing surface of the upper mold 3, a filling recess 8 for filling rubber as a molding material is formed in communication with the cavity 5. That is, in this embodiment, the upper end surface of the medium core 7 is set so as to slightly sink into the hole 4, whereby the filling concave portion 8 is formed.
Are formed.

Further, in order to introduce the molding material into the filling recess 8,
A runner 9 is formed between the upper mold 3 and the middle mold 2,
Introducing passage 1 for press-fitting the molding material into filling recess 8
0 is formed. As shown in FIG. 2, the runner 9 is set so that the distances to the respective holes 4 are uniform with the introduction path 10 of the molding material as a base point. As a result, the injection pressure of the molding material applied to the introduction passage 10 is evenly applied to the lower mold core 6 and the middle mold core 7 corresponding to the holes 4.

Therefore, as shown in FIG. 1, the lower mold 1, the middle mold 2, and the upper mold 3 are
When the molding material is injected from the introduction passage 10 with a predetermined injection pressure in a state where the molding material is clamped to each other, the molding material is introduced into each hole 4 through the runner 9.

Then, the molding material introduced into each hole 4 is filled into the filling concave portion 8 between the upper end surface of the middle die core 7 and the facing surface of the upper die 3, and further into the cavity 5. At this time, the injection pressure of the molding material is evenly applied to the upper end surface of each middle-sized core via the molding material filled in each filling recess 8, and each middle-sized core 7 is pressed toward each lower-molded core 6. It by this,
The middle mold core 7 and the lower mold core 6 forming the cavity 5 are individually clamped with an equal pressure to firmly seal the mold surfaces, and the molding material is prevented from leaking from the cavity 5. As a result, it is possible to prevent burrs from occurring in each of the plurality of molded products.

As described above, in this embodiment, when a plurality of rubber products are molded at the same time by a set of molding dies, the middle mold core 7 and the lower mold core 6 forming the cavities 5 are always molded with a uniform pressure. It can be tightened, and it is possible to prevent burrs from occurring in all the molded products.

Moreover, in the molding die of this embodiment, as a molding material other than a molding product, as shown in FIG.
Most of the molding material remains in the filling recess 8 and the runner 9 corresponding to the above, and unlike the case where the proportion of the molding material remaining on the entire surface of the pot 28 in the conventional pot-type mold is large. The yield of molded products can be improved.

Further, in the molding die of this embodiment, no special processing is required other than setting the wall thickness of the middle-sized core 7 to be slightly small. Unlike the case of increasing the size or assembling the compression spring 38, the structure can be simplified and the maintenance can be simplified.

The invention is not limited to the above embodiment,
A part of the configuration may be appropriately modified and implemented as follows without departing from the spirit of the invention.

(1) In the above-mentioned embodiment, the lower mold 1, the middle mold 2, and the upper mold 3 are arranged so as to open the mold clamping mold in the vertical direction.
You may arrange | position them so that a mold closing mold may be opened laterally.

(2) In the above embodiment, the cavity 5 is formed between the middle mold core 7 and the lower mold core 6, but the lower mold core 6 is omitted and the cavity is formed between the lower mold 1 and the middle mold core 7. May be.

(3) In the above-mentioned embodiment, the filling recess 8 is formed in each hole 4, but the filling recess 8 may be formed on the upper mold 3 side facing each hole 4.

(4) In the above-described embodiment, the molding die for a rubber product is embodied, but it may be embodied as a molding die for a resin product other than that.

[Effect of the Invention] As described in detail above, according to the present invention, since a plurality of molded products are simultaneously molded by a set of molding dies, the yield of the molded products can be improved, and moreover, This has an excellent effect that the mold structure can be simplified and the maintenance can be simplified.

[Brief description of drawings]

FIG. 1 is a vertical cross-sectional view of a main part of a molding die showing an embodiment embodying the present invention, and FIG. 2 is a plan view of a middle die thereof. FIG. 3 to FIG. 6 are drawings showing a conventional example.
FIG. 4 is a vertical sectional view showing the pot type mold, FIG. 4 is a plan view of the middle type mold, FIG. 5 is a vertical sectional view showing the spring type mold, and FIG. 6 is a plan view of the medium size mold. 1 ... lower mold, 2 ... medium mold, 3 ... upper mold, 5 ... cavity, 7 ... medium core, 8 ... filling recess, 9 ... runner.

Claims (1)

[Scope of utility model registration request] 1. A lower mold (1), a middle mold (2) that can be contacted and separated from the lower mold (1), an upper mold (3) that can be contacted and separated from the middle mold (2), and the middle mold (2). ), A plurality of molding cores (7), molding cavities (5) formed between the cores (7) and the lower mold (1), and a molding material. A filling recess (8) formed between the end surface of each core (7) and the facing surface of the upper mold (3) for filling, and formed in communication with each cavity (5); A molding die, comprising: a runner (9) formed between the upper mold (3) and the middle mold (2) for introducing a molding material into the filling recess (8). Type.