JP2990749B2 - Molding method of thermoplastic resin FRP molded product - Google Patents

Description

Description: TECHNICAL FIELD The present invention relates to a method for molding a thermoplastic resin FRP molded product, and more particularly to a molding method suitable for molding a molded product requiring high dimensional accuracy. It is.

[Prior art] Since a thermoplastic resin has a property of softening when heated and hardening when cooled, when a desired molded article is molded using the thermoplastic resin, it is heated and then cooled. In the cooling step, it is necessary to cool the molded product while maintaining the dimensional accuracy and the like of the molded product.

Conventional methods for molding molded articles include hot pressing and injection molding.However, all of these methods involve placing a heated product in a cold mold, so that the molded product has a surface And it cannot be molded with high precision.

In order to solve such a problem, it is necessary to melt once in a mold before molding.

In order to obtain a high-precision molded article of thermoplastic resin FRP by melting the whole in a mold and cooling after molding, a mold with high precision and large heat capacity is prepared, and the mold is prepared. This is possible if the mold is heated or cooled.

[Problems to be Solved by the Invention] However, when a high-precision thermoplastic resin FRP molded product is molded using the high-precision mold having a large heat capacity, the mold is heated and then cooled. Since the mold must be heated and cooled, there is a problem that the molding cycle time is prolonged and the energy consumption is increased.

Therefore, the present inventors have paid attention to the fact that in the case of cooling and hardening after being melted in the mold, it is not necessary to provide precision during heating, and it is sufficient to provide precision during cooling. As a result of repeated studies on whether the mold can be changed between heating and cooling, the inventors have found that the mold can be divided into two and formed, and made the present invention.

Therefore, an object of the present invention is to reduce molding cycle time and energy consumption by using different molds for heating and cooling.

[Means for Solving the Problems] In order to solve the above-mentioned problems, the present invention provides a method in which a large mold including upper and lower mold portions for securing a large heat capacity and accuracy is provided.
A small metal mold having a small heat capacity and comprising upper and lower mold parts provided with a heating means is positioned, and the small mold is supported on a lower mold part of a large mold by an elevating device. The upper and lower mold parts of the large mold are separated from each other in the vertical direction, and the small mold is lifted by the lifting device to separate the large mold and the small mold, and then only the small mold is heated. Melting the molding material placed in the small mold,
Next, in the cooling step, the small mold is lowered by an elevating device to fit into the recess on the upper mold part upper surface of the large mold and the small mold is fitted into the concave part on the lower mold part lower surface of the large mold. The small mold is integrated with the large mold by fitting the upper mold portion of the mold, and the molded article is cooled by pressing the small mold with the large mold.

[Operation] A small mold composed of upper and lower mold parts is previously positioned between a large mold composed of upper and lower mold parts, and the small mold is moved to a lower mold part of a large mold by an elevating device. In the heating step, the upper and lower mold parts of the large mold are separated vertically, and then the small mold is lifted from the lower mold part of the large mold by the lifting device. Since only the small mold is heated after separating the small mold from the large mold,
The heating time can be shortened, and in the cooling step, a small mold is fitted to a large mold for ensuring accuracy, so that accuracy can be ensured. Large molds are kept at almost constant temperature throughout the process without heating or cooling,
In the heating step, the molding cycle time can be shortened and the energy consumption can be reduced by heating only the small mold.

Embodiments Hereinafter, embodiments of the present invention will be described with reference to the drawings.

FIG. 1 shows an apparatus for carrying out the molding method of the present invention. The apparatus has a surface corresponding to a molded product (a blade is shown in the figure) 6 to be molded, and has a heater 2 as a heating means. The upper and lower mold portions 1a and 1b having the small heat capacity, that is, the small mold 1 and the upper and lower mold portions 1a and 1b of the small mold 1 The upper and lower mold portions 3a and 3b, which have finished the concave portion 4 that can be fitted with high precision, have a large heat capacity, that is, the large mold 3 is formed separately, and the small mold 1 is heated. And the large-sized mold 3 is used as a mold for a portion for ensuring accuracy. Further, during the molding operation of the molded product, the small mold 1 is located between the large molds 3 and the lower mold portion 3b of the large mold 3 is placed at the center of the lower mold portion 3b. Actuators such as a plurality of jacks are installed in the vertical direction as lifting devices 5 for lifting and lowering the lower mold portion 1b of the small mold 1 fitted in the recess 4 of 3b and separating the lower mold portion 1b from the recess 4. The small mold 1 is supported by the device 5.

In the molding method of the present invention, as shown in FIG.
And cooling step II. In the heating step I, heating is performed from room temperature to the melting temperature of the resin. In the next cooling step II,
The molded article material heated and melted in the heating step I is pressurized, cooled and cured.

Now, in the heating step I, as shown in FIG. 1, the upper and lower mold parts 3a and 3b of the large mold 3 are separated from each other in the vertical direction, and the elevating and lowering device 5 is extended to remove the small mold 1. By lifting the large mold 3 above the lower mold part 3b,
The large mold 3 and the small mold 1 are kept separated. Next, in this state, after the molding material 6 made of the thermoplastic resin FRP is put in the small mold 1 composed of the upper and lower mold parts 1a and 1b, the small mold 1 is heated by the heater 2 as a heating means. Only the material is heated to melt the molded article material 6 in the small mold 1. In this heating step I, since only the small mold 1 is heated, the heating time can be shortened.

Next, in the cooling step II, precision is required because the molded product material 6 melted in the small mold 1 is cooled and hardened into a molded product 7. Therefore, in this step II, in order to ensure accuracy, the upper mold part 1a of the small mold 1 is fitted into the concave part 4 of the upper mold part 3a of the large mold 3, and the small mold The lower mold portion 1b of the large mold 3 is fitted into the concave portion 4 of the lower mold portion 3b of the large mold 3, and the small mold 1 is integrated with the large mold 3 as shown in FIG. To When the small mold 1 is fitted to the large mold 3 in this manner, a pressing force is applied to the large mold 3 in this state, and the small mold 1 is securely clamped, and the small mold 1 is clamped. Type 1
Is molded while being cooled to cure the molded article 7. In this case, the mold 3 having a large heat capacity and ensuring accuracy is maintained at a substantially constant temperature throughout the entire process, and the mold 3 is heated and heated.
The cycle time can be greatly reduced as compared with the case of cooling.

When the molded article 7 is hardened in the cooling step II, the large mold 3 is released from the mold, and the elevating device 5 is extended to operate the small mold from the lower mold portion 3b of the large mold 3. 1
Then, the lower mold part 1b is separated, and thereafter, the molded product 7 is taken out from the small mold 1.

[Effects of the Invention] As described above, according to the molding method of the molded article of the present invention, the heat capacity is small and the heating means is provided between the large dies having the large heat capacity and the upper and lower mold parts for securing accuracy. The small mold consisting of the upper and lower mold parts provided is positioned, and the small mold is supported on the lower mold part of the large mold by an elevating device. The small mold is heated by heating only the small mold after separating the large mold and the small mold by lifting the small mold by the lifting device and separating the mold part in the vertical direction. In the cooling step, the small mold is lowered by an elevating device so as to be fitted into a recess on the upper surface of a lower mold portion of the large mold, and the large mold is then cooled in a cooling step. Insert the upper mold part of the small mold into the concave part on the lower surface of the upper mold part to convert the small mold to the large mold In order to form a molded product with high-precision thermoplastic resin FRP by pressing the small mold with a large mold and cooling the molded product, a large heat capacity mold The molding cycle time can be reduced as compared with the case where a molded article is molded by heating and cooling, and the energy consumption associated therewith can be reduced. As soon as only the small mold located between the small molds is heated to melt the molding material between the small molds, the small mold is immediately fitted into the recesses of the upper and lower mold portions of the large mold. It is not necessary to carry a small mold and fit it into a large mold, and it is possible to achieve shorter cycle time and energy saving. Excellent curing can be achieved.

[Brief description of the drawings]

FIG. 1 is a sectional view showing an embodiment of an apparatus for carrying out the molding method of the present invention, FIG. 2 is a block diagram showing the molding steps of the molding method of the present invention, and FIG. It is sectional drawing which shows the state at the time of cooling in a cooling process. 1 small mold, 1a upper mold part, 1b lower mold part
2 ... heater (heating means), 3 ... large mold, 3a ...
Upper mold part, 3b Lower mold part, 4 recess, 5 lifting device, 6 molding material, 7 molded product.

Continuation of the front page (58) Field surveyed (Int.Cl. ⁶ , DB name) B29C 43/32-43/42 B29C 43/52-43/58 B29C 33/00-33/08 B29C 51/30-51 / 42

Claims (1)

(57) [Claims] 1. A small mold having a small heat capacity and comprising upper and lower mold parts provided with a heating means is positioned between a large mold composed of upper and lower mold parts for securing accuracy having a large heat capacity.
The above small mold is supported on the lower mold part of the large mold by an elevating device, and the upper and lower mold parts of the large mold are separated vertically in the heating step, and the small mold is moved by the elevating device. Is lifted to separate the large mold and the small mold, then only the small mold is heated to melt the molded material placed in the small mold, and then, in a cooling step, The small mold is lowered by an elevating device to fit into the concave part on the upper mold part of the large mold and the upper mold of the small mold in the concave part on the lower mold part of the large mold. A thermoplastic resin FRP molded article characterized in that a small mold is integrated with a large mold by fitting the part, and the small mold is pressed by a large mold to cool the molded article. Molding method.