JP2537230Y2 - Clamp structure of resin mold - Google Patents

Description

[Detailed description of the invention]

[0001]

The present invention relates to a metal plate for a resin molding die in which a metal plate is used on one side of a mold, a resin plate is used on the other side, and a fluid flow path is formed between the two. The present invention relates to a clamp structure between a resin and a resin plate.

[0002]

2. Description of the Related Art For example, when manufacturing a resin molded product having an extremely thick cross-section such as a bathtub, it is usual to use upper and lower dies which are male and female fitted. This is intended to improve the shape accuracy of the product by holding and holding the resin material in the upper mold and the lower mold until the resin material is sufficiently cured.

[0003] When the conventional upper and lower molds are roughly classified, FIG.
There are a resin mold (FRP mold) 1 shown in FIG. 0, an electroforming mold 2 shown in FIG. 11, and a mold 3 shown in FIG. In addition, all the drawings partially show one of the upper and lower molds. Resin mold 1
The backing material 4 is formed of an unsaturated polyester resin reinforced with a fiber such as glass, and a surface material 5 is provided by coating the same surface with an unsaturated polyester resin of the same quality, and a mold is formed. In molding a resin product, an upper mold and a lower mold are combined, a resin raw material is poured into a molding space between the two, and this is cured to obtain a molded product. In the case of natural curing, however, it takes a considerable amount of time to cure to the extent that shape retention is not lost even when the mold is released, and there is a disadvantage that productivity is poor. Therefore, in the conventional resin mold 1, the temperature of the external atmosphere is increased, and heat is applied to the resin raw material by utilizing the heat conduction of the resin mold 1 so that the resin raw material is cured.

In the electroforming mold 2, a material obtained by mixing an epoxy resin and sand is used as a backup material 6, and a steel pipe is buried in a meandering shape when the backup material 6 is formed to provide a flow path 7 for a heat medium. Then, Cu is added to the surface side of the backup material 6.
The plating 8 and the Ni plating 9 are alternately repeated to obtain a surface material 10 having a multilayer structure, and a mold is formed. In the electroforming mold 2, it is possible to heat the resin raw material by flowing a heat medium such as hot water into the flow channel 7, and it is possible to cure the resin raw material in a shorter time than the resin mold 1 described above.

On the other hand, the mold 3 forms a backup material 11 by casting a metal material, and performs a boring process on the backup material 11 to form a heat medium passage 12.
Then, the surface material 13 is formed by applying Cr plating to the surface side of the backup material 11, and a mold is formed. In the case of the mold 3 as well, the heat medium can be circulated through the flow channel 12 to heat and cure the raw resin, so that the production efficiency is extremely excellent.

[0006]

However, in the conventional resin mold 1, as described above, the temperature of the external atmosphere is increased, and the resin material is heated and cured by utilizing the heat conduction of the resin mold 1. ing. Therefore, the heat transfer coefficient is extremely low,
It only takes about 60 minutes to apply a gel coat layer to the molding surface (surface of the surface material 5) of the resin mold 1 for producing the bathtub, and it takes about 60 minutes. It took more than two hours to cure the resin, and as a whole, as long as five hours. In addition, since the surface material 5 of the resin mold 1 is formed of a resin material such as unsaturated polyester, there is a disadvantage that the formed surface is easily damaged, which adversely affects the surface properties of the product. Furthermore, the resin mold 1 undergoes a temporal change such that its size is reduced while heating and cooling are repeated. Therefore, there is also a disadvantage that the life of the resin mold 1 is several hundred times and is extremely short.

Further, in the conventional electroforming mold 2, a steel pipe is arranged in a meandering manner in the backup material 6 so that a heat medium flow path 7 is formed.
Has to be formed, and there is a drawback that the production is troublesome. In addition, in the electroforming mold 2, since the heat medium of the flow path 7 arranged at the predetermined intervals is a heat source, the heat conduction to the molding surface becomes non-uniform having a partial strength portion, and the resin molding is performed. There are fatal drawbacks for a resin molded product such as cracks generated in the product and reduced boiling performance. In addition, this electroforming mold 2 has C
The disadvantage is that the surface material 10 must be formed by repeating the u plating 8 and the Ni plating 9, which requires much labor.
There is a disadvantage that the cost is high.

Furthermore, in the conventional mold 3, since the backup material 11 is a cast product, even a type for manufacturing a bathtub becomes extremely heavy, 15 tons, and is inconvenient to handle. there were. In addition, in order to form the flow path 12 for the heat medium in the backup material 11, a boring process must be performed. Moreover, in the case of the mold 3 as well, since the flow paths 12 are arranged at predetermined intervals, as in the case of the electroforming mold 2, cracks are generated in the formed product and the boiling performance is reduced. was there.

[0009]

SUMMARY OF THE INVENTION In view of the above-mentioned problems, the present invention has been improved and eliminated. In this invention, the front side and the back side of a mold are formed of different materials, and the thermal expansion difference at the peripheral edge thereof is obtained. It is an object of the present invention to provide a resin molding die capable of making the entire inside of the die a flow path by adopting a clamp structure for absorbing heat, and capable of dramatically improving heat transfer efficiency.

Means adopted by the present invention to solve the above-mentioned problem is to provide a mold for resin molding in which a flow path of a heating medium such as hot water is provided inside the mold. While molding with a metal plate, the other side of the mold is molded with a resin plate, a mold is provided between the metal plate and the resin plate at the peripheral edge of the mold, and the metal plate and the resin plate are separated from each other. Each is individually bolted to the formwork.

[0011]

The resin molding die of the present invention is formed by molding one side of the molding die with a metal plate and the other side with a resin plate and interposing a mold frame on the peripheral edge of both plate materials. Are individually fixed to the formwork. This makes it possible to absorb the difference in thermal expansion generated between the two plate members, and it is possible to use the entire space between the two plate members as a flow path for a heat medium such as hot water. for that reason,
The heat can be uniformly and efficiently transferred to the entire surface of the molding surface, so that the curing time of the resin material can be significantly reduced and cracks can be prevented.

[0012]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS The configuration of the present invention will be described below with reference to the drawings based on an embodiment in which the present invention is applied to a mold for forming a bathtub.

FIGS. 1 to 3 show an upper mold 14 for resin molding according to an embodiment of the present invention, and FIG.
4, FIG. 2 is a vertical sectional front view of the upper mold 14, and FIG. As shown in the figure, the upper mold 14 is provided with a chamber through which warm water passes, and is divided into eight chambers A to H as a whole. And each room A
H are provided with ribs 15 having both a rectifying action and a reinforcing action. The ribs 15 form flow paths 16 in each of the chambers A to H, through which the warm water flows evenly in each of the chambers.

As shown in FIG. 4, the upper mold 14 is manufactured by integrally projecting a rib 15 on a resin plate 17 made of FRP resin material or the like, and disposing an FRP plate 18 on the rib 15. The flow path 16 is formed, and finally the FRP resin material 19 is overlaid. As another method of manufacturing the upper mold 14, as shown in FIG.
7, an aluminum frame or the like having an H-shaped cross section is placed thereon to form a rib 15, and then, as in the case shown in FIG. 4, an FRP plate 18 is arranged on the rib 15 to form a flow path 16. And finally FR
This is performed by overlaying the P resin material 19.

On the other hand, as shown in FIGS. 6 and 7, the lower mold 20 is divided into three chambers J, K, and L in the vertical direction.
In each of the divided chambers, the ribs 15 are provided as in the case of the upper mold 14 described above, and the flow path 16 is formed so that the hot water flows uniformly in each of the chambers. As shown in FIGS. 6 and 8, one side (molding side) of the lower mold 20 is formed of a metal plate 21 made of aluminum alloy or the like, and the other side is formed of a resin plate 22 made of FRP or the like. Molded with. Lower mold 20
The resin plate 17 shown in FIGS.
Instead, the procedure may be performed in the same manner. Molding surface side is metal plate 21
The reason is that the heat conduction is better than in the case of molding with a resin plate, and the curing time of the resin material for manufacturing a molded product can be shortened. In addition, since the surface is very dense and a smooth surface close to a mirror surface, the surface properties of the molded product should be improved. Furthermore, there are many advantages such as a longer life than a mold formed from a resin plate.

Thus, the lower mold 20 is thus attached to the metal plate 21.
When formed of a different material of the resin and the resin plate 22, the thermal expansion coefficients of the two materials differ due to a heat medium such as hot water flowing through the flow path 16, and the lower mold 20 itself may be deformed. Therefore, in this embodiment, a clamp structure as shown in FIG. 8 is used to absorb the difference in thermal expansion between the different materials. That is, a part of the mold frame 23 that is placed on the conveyor and moves on the production line is interposed between the metal plate 21 of the lower mold 20 and the peripheral edge of the resin plate 22. And this form 23
Then, the metal plate 21 and the resin plate 22 are fixed with separate bolts 26 and 27 via seal packings 24 and 25, respectively. Thereby, even if there is a difference in thermal expansion between the metal plate 21 and the resin plate 22, since the metal plate 21 and the resin plate 22 are not directly connected and fixed, the difference in thermal expansion between the metal plate 21 and the resin The absorption is alleviated. In FIG. 8, reference numeral 28 denotes a mold frame for attaching the upper mold 14.

Next, a method of manufacturing a bathtub using the upper mold 14 and the lower mold 20 configured as described above will be described with reference to FIG. First, a release material 29 is applied to the molding surface of the lower mold 20,
The entire lower mold 20 is preheated at a temperature of 65 ° C. Subsequently, a gel coat material 30 is applied. On the other hand, lower mold 1
In No. 4, a mold release material 29 is applied to the molding surface. In this embodiment, these upper and lower dies 14 are used.
And 20 are matched and clamped as shown in FIG.
Resin concrete 3 to molding space formed between upper and lower molds
1 is injected. This injection can be performed at very low pressure. Therefore, it is possible to reduce the thickness of the upper and lower dies 14 and 20.

After the resin concrete 31 is injected, hot water (heat medium) at 85 ° C. is injected into each of the divided chambers A to H or J to L of the upper mold 14 and the lower mold 20 and circulated in each chamber. ing. The hot water of 85 ° C. injected into each of the chambers A to H or J to L is rectified so as to flow evenly in each of the chambers by the rib 15 which also has a reinforcing action. At this time, in each chamber, each chamber is divided and the flow path is formed such that the temperature difference between the inflow side and the outflow side of the hot water is within a range of ± 5 ° C. That is, care is taken so that the temperature of the hot water on the outflow side of each chamber does not fall below 80 ° C.
The hot water of 85 ° C. supplied to each chamber exchanges heat with its molding surface while rotating around each chamber by the ribs 15. In addition, since the heat exchange in this case is performed using hot water in each chamber of the upper and lower dies 14 and 20, the heat exchange is uniform over the entire surface of each chamber, that is, on the entire molding surface side of the upper and lower dies 14 and 20. Heat exchange is performed. By this heating, the resin concrete 31 injected into the molding space is heated and hardened.

The heating of the resin concrete 31 by the heat exchange with the hot water is carried out in the upper mold 14 through one extremely thin resin plate 13 shown in FIG. 4 and FIG. The conduction is performed by conduction, and in the case of the lower mold 20, the conduction is performed by heat conduction through a metal plate 21 that is a single thin plate such as an aluminum alloy. Therefore, a remarkable improvement in heat transfer efficiency is obtained as compared with the conventional type shown in FIGS. 10 to 12, and the hardening time of the resin concrete 31 can be greatly reduced.

By the way, when the resin concrete 31 starts to be hardened by the heating, the resin concrete 31 itself exhibits a heating effect. In this case, when the temperature becomes high, for example, over 100 ° C., the thermal expansion and contraction becomes large, and there is a problem in the production of cracks. However, said 85
Upper and lower dies 14 and 2 of this embodiment for heating with hot water of
On the other hand, when the temperature is 0, the resin concrete 31 has a function of cooling the resin concrete 31 when the temperature becomes too high. Therefore, in the upper and lower dies 14 and 20 of this embodiment, it is possible to prevent the resin concrete 31 from generating cracks due to its own heat generation.

After the resin concrete 31 is hardened by heat exchange with warm water, the upper and lower dies 14 and 20 are removed from the mold.
Take out the molded product. Then, a back-up material 32 such as FRP is provided on the back side by spray coating or the like. Next, this is placed in a curing furnace and heated at, for example, 40 ° C. to cure the backup material 32.

As described above, by using the upper and lower dies 14 and 20 and heating the resin material, which is the main part of the resin molded product, with the hot water flowing in the mold, conventionally, it takes 5 hours to form one bathtub. However, in this embodiment, the bathtub 33 can be formed in 1 hour and 30 minutes.

Incidentally, the present invention is not limited to the above-described embodiment, but can be appropriately changed. For example, the formation of the backup material 32 such as an FRP
Although the case where lay-up is performed by spray coating or the like on the rear surface side of the molded body removed from the molds 4 and 20 and taken out has been described, the molded body may be formed in the upper mold 14 in advance. On the other hand, in the lower mold 20, a glass mat may be provided on the gel coat material 30 to form a transparent FRP layer between the gel coat material 30 and the resin concrete 31. is there. Further, the present invention can be applied to other resin molded products such as a wash counter and a kitchen counter other than the bathtub. In such a case, in each mold, the number of chambers, the number of installed ribs, the installation pattern, the flow path pattern, and the like may be set according to the shape and type of the product, the properties of the resin, and the like. 4 and 5
The lower surface side (molding surface side) of the upper die 14 shown in FIG. 1 can be formed of a metal plate such as an aluminum material.

[0024]

[Effect of the Invention] As described above, in the present invention,
One side of the mold for resin molding is molded with a metal plate, the other side is molded with a resin plate, and a mold is interposed between the two plates at the peripheral edge so that both plates are individually attached to the mold. Accordingly, the difference in thermal expansion between different materials due to a heat medium such as hot water formed between the two plate members can be absorbed by the mold. Therefore, a mold can be formed using a thin metal plate, and a resin mold excellent in heat conduction can be provided. As a result, the time required for thermosetting the resin material can be significantly reduced, and excellent production efficiency can be obtained. Also, during the curing process of the resin material, it generates heat by itself and may cause cracks, but in the resin molding die of the present invention, warm water flowing in the mold also has an effect of cooling the resin material. , Cracks can be prevented.

[Brief description of the drawings]

FIG. 1 is a cross-sectional plan view of an upper die according to the present invention.

FIG. 2 is a vertical sectional front view of the upper die according to the present invention.

FIG. 3 is a vertical sectional right side view of the upper die according to the present invention.

FIG. 4 is a vertical sectional view showing a molding procedure of the upper die according to the present invention.

FIG. 5 is a longitudinal sectional view for explaining another molding procedure of the upper die according to the present invention.

FIG. 6 is a longitudinal sectional view of the lower mold according to the present invention.

FIG. 7 is a plan view of the lower die according to the present invention.

FIG. 8 is a partially enlarged longitudinal sectional view showing the lower clamp structure according to the present invention.

FIG. 9 is a view showing a manufacturing process of the bathtub according to the present invention.

FIG. 10 is a partial longitudinal sectional view showing a conventional resin mold.

FIG. 11 is a partial longitudinal sectional view showing a conventional electroforming mold.

FIG. 12 is a partial longitudinal sectional view showing a conventional mold.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 14 ... Upper mold 15 ... Rib 16 ... Resin plate 20 ... Lower mold 21 ... Metal plate 22 ... Resin plate 30 ... Gel coat 31 ... Resin concrete 32 ... Backup material 33 ... Bathtub

 ──────────────────────────────────────────────────続 き Continuation of the front page (56) References JP-A-63-252708 (JP, A) JP-A-2-8028 (JP, A) JP-A-57-103810 (JP, A) 70912 (JP, U) Japanese Utility Model 5-24320 (JP, U) Japanese Utility Model 56-173421 (JP, U) Japanese Utility Model 56-102021 (JP, U) Japanese Utility Model 56-62525 (JP, U) Jiko 32-10871 (JP, Y1)

Claims (1)

(57) [Scope of request for utility model registration] 1. A mold for resin molding in which a flow path of a heat medium such as hot water is provided inside a mold. One side of the mold is molded with a metal plate, and the other side of the mold is molded with a resin plate. A mold is disposed between the metal plate and the resin plate at the periphery of the mold, and the metal plate and the resin plate are individually attached to the mold by bolts. Clamp structure for resin mold.