JP3777073B2 - Molding method and molding apparatus for resin molded product - Google Patents

Description

[0001]
BACKGROUND OF THE INVENTION
The present invention relates to a molding method and molding apparatus for a resin molded product made of a thermoplastic resin such as polystyrene or polypropylene.
[0002]
[Prior art]
As a molding method and a molding apparatus for such a resin molded product, for example, Japanese Patent Application Laid-Open No. 9-48065 discloses a mold having a cavity (female mold) and a hot plate (male mold) facing the cavity. The resin sheet sandwiched between these molds and the hot plate is heated and softened by the hot plate, and then the inside of the cavity is vacuum-sucked from a plurality of small holes formed on the inner surface of the cavity, thereby the resin sheet and the cavity. By exhausting the air between the inner surface and blowing compressed air from the hot plate side, the resin sheet is sandwiched between the resin plates to create a pressure difference so that the hot plate side of the cavity is higher than the mold side. A sheet is described in which a sheet is brought into close contact with the inner surface of a cavity and molded into a predetermined molded product shape.
[0003]
[Problems to be solved by the invention]
By the way, when the resin molded product molded in this way is used as a container or the like, for example, in order to attach a lid to the opening, the size and shape of the opening must be accurately molded into a predetermined size and shape. Is important. Recently, in order to cover a container made of such a resin molded product, a flange portion extending to the outer peripheral side is formed at the opening edge of the container, and a film-like lid is welded to the end surface of the flange portion by ultrasonic waves. However, when attaching a lid by such a method, the inner diameter of the flange portion, that is, the inner diameter of the opening of the resin molded product or the thickness of the flange portion is used. If the error in the dimensional accuracy is large, or the flange portion is deformed such as wrinkles or distortion, the lid cannot be securely attached with an appropriate strength.
[0004]
However, in the conventional molding method and molding apparatus as described above, when compressed air is supplied from the male mold side and the resin sheet is brought into close contact with the inner surface of the cavity, the resin sheet is formed between the end surfaces of the female mold and the male mold. Since the heated and softened resin sheet is expanded and deformed by compressed air, the resin sheet portion at the periphery of the opening of the cavity, that is, the opening of the resin molded product There is a possibility that the resin of the portion that becomes the flange portion is also pulled to the bottom side of the cavity and stretched. As a result, the thickness of the opening or the flange becomes smaller than a predetermined dimension, or the thickness is deviated in this way, so that deformation easily occurs, and wrinkles or distortion occurs when cooled after molding. As a result, there is a risk of hindering the attachment of the lid.
[0005]
In such a molding apparatus, when molding a resin molded product that is not very large, it is common to form a plurality of cavities in one female mold and mold many resin molded products at once. In this case, the male mold is formed in a shallow box shape that opens to the female mold side and covers the openings of all the cavities so that compressed air is supplied to all the cavities with an equal pressure. However, in such a case, when the resin sheet sandwiched between the female mold and the male mold is brought into close contact with the inner surface of the cavity, the resin sheet is pressed against the end surface of the female mold at the peripheral edge of the cavity by compressed air. As a result, the molding accuracy of the flange part of the resin molded product is more likely to be impaired, and in the male mold formed in a box shape, compressed air must also be supplied to the part between the cavities. As a result, the supply volume increases, and it takes a long time to generate a predetermined pressure difference, resulting in a long molding cycle, and a lot of compressed air is required, thus preventing energy saving.
[0006]
The present invention has been made under such a background. In particular, the periphery of the opening of a resin molded product to be molded is accurately molded into a predetermined size and shape, and compressed air or the like for generating a pressure difference is used. An object of the present invention is to provide a molding method and molding apparatus for a resin molded product capable of reducing the supply volume.
[0007]
[Means for Solving the Problems]
In order to solve the above-described problems and achieve such an object, the molding method of the present invention includes a resin sheet that has been heated and softened, facing a female mold in which a plurality of cavities are formed, and the cavity. The resin sheet is sandwiched between a female mold that is relatively separable from the female mold and a pressure difference is generated between the female mold side and the male mold side of the cavity with the resin sheet interposed therebetween. In a molding method of a resin molded product in which the inner surface of the female mold is molded into a molded product shape in close contact with the inner surface of the cavity, a clamp portion is aligned with an end surface facing the female mold side of the male mold according to the position of the opening of the cavity of the female mold to form a, the above-mentioned male mold, a compressed air source via a solenoid valve to form a supply path of the compressed air connected, by clamping the resin sheet by the clamp portion, each of said cavities As state tightly separate, by supplying compressed air through the supply passage, characterized by creating a pressure differential in the cavity. Further, the molding apparatus of the present invention includes a female mold in which a plurality of cavities are formed, a male mold that is opposed to the female mold and can be relatively separated from and connected to the female mold, and the female mold and the male mold. Pressure generating means for creating a pressure difference between the female mold side and the male mold side of the cavity with a resin sheet sandwiched between the female sheets, and an end face facing the female mold side of the male mold, A clamp part is formed in accordance with the position of the opening of the cavity of the mold, and a compressed air supply path connected to a compressed air source as the pressure generating means via a solenoid valve is formed on the male mold. Then, the resin sheet is clamped by the clamp portion so that each of the cavities is airtight and independent, and compressed air is supplied through the supply path .
[0008]
Therefore, according to such a molding method and molding apparatus, when the softened resin sheet is sandwiched between the male mold and the female mold, the clamp portion formed in the male mold is the opening of the female cavity. In this state, the resin sheet is brought into close contact with the cavity inner surface by clamping the portion that becomes the periphery of the opening of the resin molded product and restraining the deformation. The resin around the periphery of the part is not stretched and is formed into a predetermined size and shape. In addition, since the individual cavities are airtightly independent by being clamped by the clamp portion, compressed air more than necessary for generating a predetermined pressure difference is not supplied. Here, the clamp part is protruded from an end face facing the male female side of the male mold, and has a peripheral wall-like inner peripheral clamp part facing the opening inner peripheral face of the cavity, and a female end face of the cavity opening peripheral edge The inner surface of the opening of the resin molded product is formed with high accuracy by the inner peripheral clamping portion, and the end portion of the opening that extends to the outer periphery of the opening is formed by the end surface clamping portion. Since the thickness, that is, the thickness of the flange portion is formed with high accuracy, it is particularly suitable when a lid is attached to the flange portion by ultrasonic welding as described above.
[0009]
In the molding method and molding apparatus of the present invention, when a pressure difference is generated between the female mold side and the male mold side of the cavity with the resin sheet sandwiched between the female mold and the male mold interposed therebetween. In the same manner as described in Japanese Patent Laid-Open No. 9-48065, compressed air may be supplied to the male mold side, and air in the cavity may be exhausted by vacuum suction on the female mold side. In addition, the air in the cavity on the female mold side is pushed out by inflating the resin sheet with the compressed air supplied to the male mold side and closely contacting the inner surface of the cavity without performing vacuum suction on the female mold side. You may make it exhaust. Further, when the resin sheet is sandwiched between the female mold and the male mold, the male mold is fixed and the female mold is moved, or conversely, the female mold is fixed and the male mold is moved, or these By moving both the male mold and the female mold, the male mold can be relatively separated from the female mold so as to face the cavity.
[0010]
DETAILED DESCRIPTION OF THE INVENTION
1 and 2 show an embodiment of the molding apparatus of the present invention. FIG. 1 shows a female mold 1, FIG. 2 shows a male mold 2, and FIGS. 3 and 4 show the molding apparatus. One Embodiment of the shaping | molding method of this invention using this is demonstrated. In addition, the resin molded product A molded by this embodiment includes a disc-shaped bottom portion B and a conical surface-shaped body peripheral portion C that gradually decreases in diameter toward the bottom portion B side as shown in FIG. A cylindrical portion D is formed on the opening side of the body circumferential portion C so as to be enlarged by one step, and an opening edge of the cylindrical portion D is formed on the opening edge of the cylindrical portion D. An annular plate-like flange portion E is formed so as to spread on the outer peripheral side.
[0011]
The female mold 1 is attached to a table (not shown) so as to be able to advance and retreat toward the male mold 2 side (lower side in FIG. 1). The end surface 1A of the female mold 1 facing the male mold 2 side has A cavity 3 is formed so as to be recessed from the end face 1A. The cavity 3 is formed in accordance with the outer shape of the resin molded product A. The inner surface of the cavity 3 has a circular bottom surface 3A, and the conical surface whose inner diameter gradually decreases toward the bottom surface 3A. An inner peripheral surface 3B having a cylindrical shape and a cylindrical surface 3C that is formed so as to increase in diameter by one step on the opening side of the inner peripheral surface 3B and reach the end surface 1A. In the molding apparatus of the present embodiment, a plurality of such cavities 3 are formed in one female mold 1 so as to open side by side in the end face 1A.
[0012]
Here, in the female die 1, a mounting hole 4 is formed in the bottom surface 3A of the cavity 3 so as to open in a circular shape having a slightly smaller diameter than the bottom surface 3A. 4, a disk-shaped bottom plate member 5 is loosely inserted so as to be supported by the female mold 1 by mounting bolts 6 so as to close the mounting holes 4, and the circular surface of the bottom plate member 5 is formed in the cavity 3. The bottom surface 3 </ b> A is defined by being arranged facing the surface. A hollow exhaust chamber 7 is formed in the female mold 1 on the back surface side of the bottom plate member 5 so as to extend in the diameter direction of the mounting hole 4. Has been released. Further, the outer diameter of the bottom plate member 5 is set to be slightly smaller than the inner diameter of the mounting hole 4 and is supported coaxially by the mounting hole 4. In place of the small holes, an exhaust groove 8 that circulates between the inner periphery of the mounting hole 4 and the outer periphery of the bottom plate member 5 and communicates with the exhaust chamber 7 at the outer peripheral edge of the bottom surface 3A. It is defined.
[0013]
In the present embodiment, the mounting hole 4 is formed in a multi-stage shape that extends from the opening on the cavity 3 side toward the bottom of the hole with a constant inner diameter and then expands the inner diameter by one step on the exhaust chamber 7 side. In addition, the bottom plate member 5 also has an outer diameter that extends at a constant diameter from the front surface side serving as the bottom surface 3 </ b> A of the cavity 3 toward the rear surface side, and is further increased in a portion where the inner diameter of the mounting hole 4 is increased. The exhaust groove 8 is formed in a multi-stage shape that expands in diameter, and the groove width W of the exhaust groove 8 is such that the mounting hole 4 and the bottom plate member 5 are expanded by one step from the opening on the bottom surface 3A side. The width is constant until it reaches the step. In the female mold 1, a flow path 9 through which a cooling medium for cooling the molded resin molded product A is circulated is formed so as to surround each cavity 3.
[0014]
On the other hand, the male mold 2 shown in FIG. 2 is also attached to a table (not shown) so as to be able to advance and retract toward the female mold 1 side (upper side in FIG. 2) facing the cavity 3 of the female mold 1. Here, the male mold 2 can be closely attached to a male main body 11 attached to the table via the support member 10 and an end surface 11A of the male main body 11 facing the female mold 1, and an air cylinder 12 and The clamper 14 includes a flat clamper 14 that can be projected and retracted toward the female mold 1 by a guide 13. The clamper 14 has a circular shape at a position corresponding to the opening of each cavity 3 of the female mold 1. Each of the opening holes 15 is provided therethrough, and a plug 16 protruding from the center of the opening hole 15 toward the female mold 1 is attached to the end surface 11A of the male main body 11.
[0015]
Even when the clamper 14 is projected to the female mold 1 side by the air cylinder 12, the end surface 14A facing the female mold 1 side is disposed at a position retracted from the tip of the plug 16. Has been made. The male main body 11 is formed with a compressed air supply passage 17 connected to a pressure generating means such as a compressed air source (not shown) via a solenoid valve. The supply passage 17 is connected to the clamper 14. Is opened in the end face 11A so as to be located inside the opening hole 15 in a state where the is attached to the male main body 11.
[0016]
A clamp portion 18 is provided at the periphery of the opening hole 15 of the clamper 14 to clamp the inner peripheral surface of the cylindrical portion C of the resin molded product A and the end surface of the flange portion E facing the male mold 2 side. ing. That is, in the present embodiment, an attachment groove 19 having an L-shaped cross section is formed in the opening on the female mold 1 side of the opening hole 15, and a clamp ring 20 is attached to the attachment groove 19. The ring 20 is formed with a cylindrical wall-shaped inner peripheral clamp portion 18A projecting toward the female mold 1 on the inner peripheral side thereof, and the end surface of the female mold 1 is formed on the outer peripheral side of the inner peripheral clamp portion 18A. An end surface clamp portion 18B having an annular plane shape facing 1A is formed, and the clamp portion 18 is defined by the inner peripheral clamp portion 18A and the end surface clamp portion 18B.
[0017]
Here, the inner diameter of the inner peripheral clamp portion 18A, that is, the inner diameter of the clamp ring 20, is made equal to the inner diameter of the portion of the opening hole 15 on the male body 11 side, and the outer diameter of the inner peripheral clamp portion 18A is The resin molded product A to be molded is made smaller than the inner diameter of the cylindrical surface 3C of the cavity 3 by the thickness on the opening side of the cylindrical portion C, and further, a cross section is provided on the outer periphery of the protruding end portion of the inner peripheral clamp portion 18A. A convex arc-shaped chamfer is made. On the other hand, the planar end surface clamp portion 18B is slightly protruded from the end surface 14A facing the female mold 1 side of the clamper 14, and further, the inner peripheral clamp portion 18A on the inner peripheral side of the end surface clamp portion 18B. The corners intersecting with the outer peripheral surface of each are formed in a concave arc shape in cross section.
[0018]
Next, an embodiment of the molding method of the present invention in the case where the resin molded product A as described above is molded by the molding apparatus of the embodiment configured as described above will be described. First, in this embodiment, the resin sheet S made of a thermoplastic resin such as polystyrene or polypropylene is softened by heating to a predetermined moldable temperature based on its material, thickness, outside air temperature, etc., and the female mold 1 and the male mold Between the two. Next, with the air cylinder 12 projecting the clamper 14 of the male mold 2 toward the female mold 1 side, the female mold 1 and the male mold 2 are advanced by the respective tables to approach each other. 3, the resin sheet S is sandwiched between the end surface 1A of the female mold 1 and the end surface 14A of the clamper 14 of the male mold 2 as shown in FIG.
[0019]
In this embodiment, a clamp portion 18 is provided at the periphery of the opening hole 15 of the clamper 14, and the clamp portion 18 is sandwiched between the female mold 1 and the male mold 2 clamper 14. 18 clamps the resin sheet S between the periphery of the opening of the cavity 3. That is, the inner peripheral clamp portion 18A of the clamp portion 18 faces the cylindrical surface 3C of the cavity 3 and clamps the portion that becomes the cylindrical portion C of the resin molded product A therebetween, and the end surface clamp portion 18B Opposite to the end face 1A of the female mold 1, the portion to be the flange E is clamped between them. At this time, the softened resin sheet S is deformed and swollen by being pushed out by the plug 16 protruding from the end face 14A of the clamper 14, and a part of the softened resin sheet S is pushed into the cavity 3 of the female mold 1. Is done.
[0020]
Then, next, while the male main body 11 of the male mold 2 is moved forward by the table, the clamper 14 is moved backward with respect to the male mold main body 11 by the air cylinder 12. While maintaining the state in which the resin sheet S is sandwiched therebetween, the plug 16 is further protruded into the cavity 3 and the resin sheet S is pushed in. When the end surface 11A of the male main body 11 is brought into close contact with the clamper 14 and the plug 16 is protruded into the cavity 3, the male main body 11 is interposed between the resin sheet S swelled in the cavity 3 and the male mold 2. As shown in FIG. 4, the compressed air is supplied from the pressure generating means through the supply passage 17 so that the male mold 2 side in the cavity 3 is at a higher pressure than the female mold 1 side with the resin sheet S therebetween. The resin sheet S is brought into close contact with the bottom surface 3A and the inner peripheral surface 3B of the inner surface of the cavity 3, and is molded into the resin molded product A having the above shape.
[0021]
At this time, the air between the inner surface of the cavity 3 and the resin sheet S extends from the exhaust groove 8 formed so as to circulate around the bottom surface 3A of the cavity 3 over the entire circumference. It is exhausted and discharged through the exhaust chamber 7. Further, the resin molded product A thus molded is cooled and cured by a cooling medium that is circulated through the flow path 9 of the female mold 1, and then the tables are moved backward to retreat the female mold 1 and the male mold 1. By separating the mold 2 from each other, the mold 2 is extracted from the cavity 3 and discharged while being integrated with the resin sheet S portion left in the form of a plate, trimmed on the outer periphery of the flange E, and provided as a product.
[0022]
Thus, according to the molding apparatus having the above-described configuration and the molding method using the molding apparatus, the clamp portion 18 is provided on the clamper 14 of the male mold 2 in accordance with the position of the opening of the cavity 3 of the female mold 1. In a state where the resin sheet S that is formed and is the periphery of the opening of the resin molded product A is clamped by the clamp portion 18, compressed air is supplied and the resin sheet S is applied to the inner surface of the cavity 3 due to a pressure difference. It can be in close contact. For this reason, the periphery of the opening of the resin molded product A is not deformed even when compressed air is supplied, and the size and shape of the resin molded product A can be accurately molded into a predetermined size and shape. For example, even when the resin molded product A is used as a container and a lid is attached to the opening after molding, the lid can be securely and properly attached.
[0023]
In addition, the resin sheet S sandwiched between the female mold 1 and the male mold 2 is clamped by the clamp portion 18 so that the portion to which the compressed air is supplied is airtightly independent from each other for each cavity 3. It will be in the state. For this reason, even when a plurality of cavities 3 are formed in the female mold 1 as in this embodiment, compressed air is supplied to the male mold 2 as a whole compared to the case where the conventional male mold is formed in a box shape. The volume of the part to be reduced can be kept small, thereby shortening the molding cycle, reducing the supply amount of compressed air to promote energy saving, and reducing the driving force of the molding device Is also possible.
[0024]
Further, in the present embodiment, the clamp portion 18 includes an inner peripheral clamp portion 18A facing the cylindrical surface 3C of the opening of the cavity 3 and an end surface clamp portion facing the end surface 1A of the female die 1 at the periphery of the cylindrical surface 3C. 18B, and by clamping the resin sheet S between the inner peripheral clamp part 18A and the cylindrical surface 3C, the inner diameter of the cylindrical part C of the opening part of the resin molded product A is particularly highly accurate. In addition, the end surface clamp portion 18B clamps the resin sheet S between the end surface 1A of the female mold 1 so that the thickness of the flange portion E of the resin molded product A is formed with high accuracy. Since the end surface is also formed flat, that is, the flange portion E can be accurately formed with a predetermined size and shape. Accordingly, when the resin molded product A is used as a container as described above, even when a film-like lid is attached to the end face of the flange E by ultrasonic welding, the flange E is particularly accurately molded. Thus, it is possible to join such a lid with certainty and appropriate strength.
[0025]
On the other hand, in the molding apparatus according to the present embodiment, the disk-shaped bottom plate member 5 is attached to the attachment hole 4 formed in the bottom surface 3A of the cavity 3 of the female die 1 so that the bottom surface 3A circulates as described above. A circumferential exhaust groove 8 is formed. When the resin sheet S is brought into close contact with the inner surface of the cavity 3 and molded into the resin molded product A, the air between the resin sheet S and the inner surface of the cavity 3 flows. The exhaust groove 8 exhausts the entire circumference. For this reason, compared with the conventional case of exhausting from a small hole formed in the bottom surface of the cavity, it is possible to ensure a large opening area to the cavity 3 without enlarging the groove width W so much. The air can be quickly discharged from the cavity 3 to the exhaust chamber 7 in order to improve the performance. Therefore, the molding speed of the resin molded product A is not limited by the exhaust speed, and the molding cycle can be further shortened to promote more efficient molding, while the resin molded product A thus molded is used. It is possible to provide a high-quality resin molded product A by preventing the trace of the exhaust groove 8 from being left behind.
[0026]
Moreover, in the present embodiment, the exhaust groove 8 is formed in the outer peripheral edge portion of the bottom surface 3A of the cavity 3, and the exhaust groove 8 is larger than the case where the same groove width W is formed on the inner peripheral side. An opening area can be ensured. Further, the outer peripheral edge portion of the bottom surface 3A of the cavity 3 is compressed air from the male mold 2 when the molded resin product A to be molded is a bottomed cylindrical cup shape as in this embodiment, for example. When the resin sheet S is supplied, the resin sheet S finally comes into close contact with the inner surface of the cavity 3. By forming the exhaust groove 8 in such a portion, air remains between the resin sheet S and the inner surface of the cavity 3. It is possible to prevent this from happening and ensure reliable exhaust, and to stabilize the shape of the resin molded product A. However, depending on the shape of the resin molded product to be molded, if the exhaust groove 8 is formed at a position corresponding to the shape of the molded product, for example, the exhaust groove 8 is formed on the inner peripheral side of the outer peripheral edge portion of the bottom surface 3A of the cavity 3. Good.
[0027]
Further, in the present embodiment, the exhaust groove 8 is formed to extend with an equal groove width W from the opening side to the cavity 3 to the groove bottom side. For example, as shown in FIG. The outer peripheral surface 5A of the bottom plate member 5 is tapered so that the diameter thereof decreases toward the back surface side of the bottom plate member 5, and the exhaust groove 8 is formed so that the groove width W gradually increases toward the groove bottom side, or FIG. As shown, an annular recess is formed on the outer peripheral surface 5A of the bottom plate member 5 so as to be recessed toward the inner periphery, so that the groove width W is larger on the groove bottom side than on the cavity 3 side opening. Then, without increasing the groove width W on the bottom surface 3A of the cavity 3, the exhaust resistance can be reduced and the air in the cavity 3 can be discharged more quickly. Moreover, even when the groove width W of the exhaust groove 8 is increased on the groove bottom side in this way, in this embodiment, the inner periphery of the mounting hole 4 formed in the female die 1 and the bottom plate member attached to the mounting hole 4 Since the exhaust groove 8 is defined by the outer periphery of 5, the outer surface 5 A of the bottom plate member 5 may be processed as described above, and the advantage that the exhaust groove 8 can be easily formed is also obtained. It is done.
[0028]
In the present embodiment, the exhaust chamber 7 is opened to the outside of the female mold 1, and the air between the resin sheet S pushed into the cavity 3 and the inner surface of the cavity 3 is compressed by the resin sheet S. When closely contacting the inner surface of the cavity 3 by air, it is exhausted from the exhaust groove 8 by being pushed out by the expanding resin sheet S, and is exhausted through the exhaust chamber 7. When the resin sheet S is brought into close contact with the inner surface of the cavity 3 by connecting the vacuum suction means as a part of the pressure generating means, a negative pressure is generated between the resin sheet S and the inner surface of the cavity 3, A larger pressure difference may be applied to the male mold 2 side of S, whereby the air can be exhausted more quickly and the molding cycle can be further shortened. 1 to 4, the female mold 1 is disposed on the upper side with the cavity 3 opened downward, and the male mold 2 is disposed on the lower side with the plug 16 projecting upward. Although they can be separated from each other, the arrangement of the female mold 1 and the male mold 2 can be appropriately set according to molding conditions and the like.
[0029]
【The invention's effect】
As described above, according to the present invention, the clamp part is provided in the male mold at a position corresponding to the openings of the plurality of cavities of the female mold, and the resin sheet is sandwiched between the female mold and the male mold. When the resin sheet in the cavity opening is clamped by this clamp part, a pressure difference is generated in the cavity, so that the periphery of the opening of the molded resin molded product is molded with high precision into a predetermined size and shape. Therefore, even when a lid or the like is attached to the periphery of the opening, it can be reliably and properly attached. Further, with the state of independent individual cavities hermetically when generating the pressure difference, it is possible to reduce the supply volume of such compressed air for generating the pressure difference, thereby shortening the molding cycle Therefore, it is possible to improve the processing efficiency, promote energy saving and reduce the driving force of the molding apparatus.
[Brief description of the drawings]
FIG. 1 is a side sectional view showing a female mold 1 in an embodiment of a molding apparatus of the present invention.
FIG. 2 is a side sectional view showing a male mold 2 in an embodiment of a molding apparatus of the present invention.
3 is a view showing a state where a resin sheet S is sandwiched between a clamper 14 of a female mold 1 and a male mold 2 in an embodiment of the molding method of the present invention. FIG.
4 is a view showing a state in which a resin sheet S is in close contact with the inner surface of a cavity 3 in an embodiment of the molding method of the present invention. FIG.
5 is a cross-sectional view showing a modification of the exhaust groove 8. FIG.
6 is a cross-sectional view showing a modification of the exhaust groove 8. FIG.
[Explanation of symbols]
DESCRIPTION OF SYMBOLS 1 Female type | mold 1A End surface 2 of Female type | mold 1 Male type 3 Cavity 4 Mounting hole 5 Bottom plate member 7 Exhaust chamber 8 Exhaust groove 11 Male type | mold main body 14 Clamper 15 Opening hole 16 Plug 17 Compressed air supply path 18 Clamp part 18A Inner circumference clamp Part 18B end face clamp part A resin molded product W groove width of exhaust groove 8

Claims (3)

The heated and softened resin sheet is sandwiched between a female mold in which a plurality of cavities are formed and a male mold that is opposed to the female mold and can be relatively separated from the female mold. In the molding method of the resin molded product, a pressure difference is generated between the female mold side and the male mold side of the cavity so that the resin sheet is brought into close contact with the cavity inner surface and molded into a molded product shape. A clamp part is formed on the end face of the mold facing the female mold in accordance with the position of the opening of the cavity of the female mold , and the male mold is connected to a compressed air source via a solenoid valve. forming a supply path of the air, by clamping the resin sheet by the clamp portion, in a state where an independent individual said cavity hermetically by supplying compressed air through the supply passage Molding method of a resin molded article, characterized in that creating a pressure differential in the cavity. A female mold in which a plurality of cavities are formed, a male mold facing the cavity and relatively separable from the female mold, and a resin sheet sandwiched between the female mold and the male mold A pressure generating means for creating a pressure difference between the female mold side and the male mold side of the cavity; and an end surface facing the female mold side of the male mold is provided with an opening of the cavity of the female mold. A clamp portion is formed in accordance with the position, and the male mold is provided with a compressed air supply path connected to a compressed air source as the pressure generating means via an electromagnetic valve. said by the resin sheet is clamped, it is a state in which each of said cavities are independent airtight resin molded article of the molding apparatus according to claim Rukoto compressed air is supplied through the supply passage by.   The clamp part protrudes from an end surface facing the female side of the male mold and faces a peripheral wall-shaped inner peripheral clamp part facing the opening inner peripheral surface of the cavity, and a female end face of the cavity opening peripheral edge The apparatus for molding a resin molded product according to claim 2, further comprising an end surface clamp portion.

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