JP2010240889A - Molding method of resin container - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a technique for a molding method of a resin container such as an automotive resin fuel tank, which surely bonds an opening periphery while including a plurality of different functions without a complicated mold structure. <P>SOLUTION: The method includes: a first step of molding each laminated sheet 10, 10 by pressure bonding and laminating a three-layer film material 11 having fuel transmission preventing function and molten resin sheets 12 and 12 to be laminated on both sides of the film 11 by a pressure roll 5; a second step of disposing the laminated sheets 10 and 10 in two sets of molding dies 20 and 20 to pressure mold the laminated sheets 10 and 10 into molded products 23 and 23 having a predetermined shape; and a third step of fitting recessed molds 21 and 21 together to pressure bond and connect the molded products 23 and 23. In the second step, the melted resin sheet 12 on one surface side of the laminated sheet 10, 10 is disposed on the recessed mold 21, 21 side, and the melted resin sheet 12 on the other surface side is disposed on protruding molds 22, 22 side. <P>COPYRIGHT: (C)2011,JPO&amp;INPIT

Description

  The present invention relates to a technique regarding a method for molding a resin container. More specifically, for example, in a molding method such as a resin fuel tank for automobiles, it has a plurality of different functions, and can easily and reliably join the peripheral edge of the opening without having a complicated mold structure. The present invention relates to a technique for a method of molding a resin container.

  Conventionally, as a fuel tank for automobiles, a resin tank is known in order to reduce the weight of the vehicle body (see, for example, “Patent Document 1”). The resin fuel tank is usually formed by blow molding a resin having a laminated structure of a barrier layer, a high density polyethylene layer, and an adhesive layer. Therefore, the resin fuel tank has a gasoline vaporization and leakage prevention function (gasoline permeation prevention function) due to the characteristics of the nylon layer constituting the barrier layer, and also has sufficient strength due to the characteristics of the high-density polyethylene layer. It has a configuration that can.

  Here, the blow molding method is a method in which a tube-shaped parison (molten resin) extruded downward from an extruder is sandwiched between a pair of concave molds, and air is blown into the parison through a blow nozzle to swell. Is in close contact with the inner wall surface of the mold, and a resin container (resin fuel tank) having a predetermined shape is formed.

  However, when a large resin fuel tank is molded by the blow molding method, the molded resin fuel tank is only limited in outer shape, and the parison has fluidity, so it grows due to its own weight, and the upper part The wall thickness tends to be thinner than the lower part. For this reason, it has been difficult to make the wall thickness uniform in a large resin fuel tank by a blow molding method. Further, in the case of a resin fuel tank having a complicated shape, it is difficult to make the wall thickness uniform because the expansion rate at the time of parison expansion differs depending on the part of the product.

  In order to improve such a point, a method of molding a resin fuel tank having a hollow body structure by forming respective concave shaped bodies as divided structures in advance and joining the peripheral edges of the openings to each other. Has been proposed (see, for example, “Patent Document 2” to “Patent Document 4”).

Japanese Utility Model Publication No. 01-04220 JP 2000-318029 A Japanese Patent No. 3047595 Japanese Patent No. 3099579

According to the above-mentioned “Patent Document 2”, in a concave mold that opens upward and has a molding surface inside, a molten resin having a laminated structure is placed on the upper opening end of the concave mold to form the molding surface. The space inside the mold to be formed is sealed, and then the space inside the mold sealed by the molten resin is made negative pressure by the operation of the intake pump, thereby bringing the molten resin into close contact with the molding surface, A molding method for molding a molded body by cooling and solidifying the adhered molten resin is disclosed.
If such a molding method is used, the molten resin is placed on the upper opening end of the concave mold in a horizontal state, and the uneven thickness due to its own weight can be improved.

  However, the thickness of the molten resin is still restricted only by the negative pressure of the intake pump, and for the resin fuel tank having a complicated shape, the expansion rate of the molten resin varies depending on the product part. It was difficult to make the thickness uniform. Moreover, since the opening peripheral part of the molded body once cooled is joined, reliable welding is difficult to be performed, and questions remain about the joining strength and airtightness.

On the other hand, according to the above-mentioned “Patent Document 3,” a molten resin in a high temperature state is sandwiched and pressed between a concave mold and a pair of convex molds to form a concave shape that constitutes an upper part and a lower part of the fuel tank. A molding method for molding a hollow resin fuel tank by molding each molded body and joining the peripheral edge portions of the molded bodies while maintaining a constant high temperature state is disclosed.
If such a molding method is used, the molten resin is placed on the upper opening end of the concave mold in a horizontal state as in the above-mentioned “Patent Document 2”, and uneven thickness due to its own weight can be improved. . In addition, even in the case of a resin fuel tank having a complicated shape, the thickness is regulated at every part of the molten resin because it is pressure-molded in the concave and convex molds, making the thickness uniform. Can be achieved.

  However, about the joining location of the opening peripheral part of each molded object, a question still remains about joining strength and airtightness. That is, the molten resin in this molding method is molded from a single resin material, and it is necessary to maintain a high temperature state of each molded body temperature and ensure sufficient strength of the molded body itself to ensure a reliable welding state. It is difficult to satisfy both of the requirements for immediate cooling of the molded body to ensure the same.

Therefore, as a technique for satisfying both of the above-mentioned requirements, according to the “Patent Document 4”, there is a molding method comprising a heating means and a heat insulation means in a concave mold and a part of a mold that forms a pair of convex molds. It is disclosed.
If such a molding method is used, the joints at the peripheral edge of the opening of each molded body can be intensively brought into a high heat state. Therefore, even a molten resin made of a single resin material is sufficient for the molded body itself. While ensuring a sufficient strength, it is possible to ensure the welded state of the molded bodies of each other, and to ensure the bonding strength and airtightness of the joint locations.

However, by providing the heating means and the heat insulation means as separate devices, the mold structure becomes complicated and large, and the equipment cost increases.
The molding methods shown in the above-mentioned “Patent Document 3” and “Patent Document 4” target a molten resin made of a single resin material, and the function of the molded resin fuel tank is the characteristic of the resin material. Therefore, it is difficult to reliably provide a gasoline permeation preventing function in a resin fuel tank that does not include a barrier layer.

  In view of the above points, in the present invention, for example, in a molding method of a resin container such as a resin fuel tank for automobiles, a plurality of different functions such as a gasoline permeation prevention function and a resin container strength holding function are provided. It is an object of the present invention to provide a technique for a method of molding a resin container that can reliably join the peripheral edge of the opening without having a complicated mold structure.

  The problem to be solved by the present invention is as described above. Next, means for solving the problem will be described.

  That is, in claim 1, the barrier layer is formed on the front and back surfaces of a three-layer film material having a barrier layer that prevents permeation of substances stored inside the resin container and an adhesive layer that is laminated on the front and back surfaces of the barrier layer. Each of the laminated sheets is disposed between a first step of forming a laminated sheet by laminating resin sheets having characteristics different from those of the layers, and a concave mold and a convex mold that can be fitted to each other. The second step of forming the laminated sheet into a molded body having a predetermined concave shape by press-molding the laminated sheet with the convex mold and the concave mold, and the second step A second step of fitting the two concave molds that hold the molded body into a direction in which the concave shapes of the respective molded bodies face each other, and pressing and bonding the molded bodies together, In the second step, the molten resin on one side of the laminated sheet Over: it is arranged on the concave mold side, in which the other surface side molten resin sheet is disposed on the convex mold side.

  As effects of the present invention, the following effects can be obtained.

  In Claim 1, for example, it has a plurality of different functions such as a gasoline permeation preventing function and a resin container strength maintaining function, and the peripheral edge of the opening is securely joined without having a complicated mold structure. A possible resin fuel tank (resin container) can be formed.

Sectional drawing which showed the structure of the lamination process part of the shaping | molding apparatus which concerns on one Example of this invention. It is the figure which showed the process of press-molding a laminated sheet to the shape of a shaping die, (a) is sectional drawing which showed the state immediately after arrange | positioning a laminated sheet between a concave mold and a convex mold, (b ) Is a cross-sectional view showing a state immediately after press-molding a laminated sheet with a concave mold and a convex mold. It is the figure which showed the process of crimping | bonding together compacts, (a) is sectional drawing which showed the state of the concave mold immediately after a convex mold detach | leaves, (b) is mold-matching concave molds Sectional drawing which showed the state immediately after having performed. Sectional drawing which showed the resin-made fuel tank shape | molded by the shaping | molding method which concerns on this invention.

  Next, embodiments of the invention will be described.

[Molding device 1]
First, the structure of the shaping | molding apparatus 1 using the molding method of the resin container in this invention is demonstrated using FIG. 1 and FIG. For convenience, the vertical direction in FIGS. 1 and 2 is defined as the vertical direction of the molding apparatus 1 and the direction of the arrow A is defined as the forward direction.

The molding apparatus 1 in the present embodiment is an apparatus for molding, for example, a resin fuel tank 50 (see FIG. 4) for an automobile in a resin container having a hollow body structure.
More specifically, the laminated sheet 10 is formed by overlapping two molten resin sheets 12 and 12 on the front and back surfaces of the film material 11 including the barrier layer 11a having a fuel (petrol) permeation preventing function in advance, The laminated sheet 10 is pressure-formed by two sets of molding dies 20 and 20 to form two sets of molded bodies 23 and 23 (see FIG. 3), and the concave molds of the molding dies 20 and 20 are formed. The resin fuel tank 50 is formed by press-bonding the molded bodies 23 and 23 together by matching the molds 21 and 21 with each other.

The molding apparatus 1 is mainly composed of a lamination process unit 2, a molding process unit 3, and the like.
First, the structure of the lamination | stacking process part 2 is demonstrated using FIG.
The laminating process unit 2 is a process unit for forming the laminated sheet 10 by superimposing the molten resin sheets 12 and 12 and the film material 11, and supplying the laminated sheet 10 to the molding dies 20 and 20. It is composed of the machines 4 and 4, the pressure roll 5, the intermediate roll 6, the bobbin 7, and the like.

  The extruders 4 and 4 are apparatuses for extruding a molten resin composed of high-density polyethylene into a sheet shape through dies 4a and 4a at the tip. Here, in the present molding apparatus 1, two extruders 4 and 4 are provided and are arranged to face each other with a predetermined dimension apart from each other in the front-rear direction. It is possible to set conditions.

A pressure roll 5 is disposed below the extruders 4.
The pressure roll 5 includes a pair of roll portions 5a and 5a, and shaft portions 5b and 5b that respectively support the roll portions 5a and 5a. The pressure rolls 5 are directed in the front-rear direction (extruders 4. (4 separation direction).

The shaft portions 5b and 5b are respectively provided with drive transmission means (not shown) composed of, for example, a drive chain, and the driving force from the drive section is applied to the shaft portions 5b and 5b via the drive transmission means. The roll portions 5a and 5a are configured to be individually driven to rotate so that the portions facing each other rotate downward.
That is, the front side (left side in FIG. 1) roll unit 5a is rotationally driven clockwise, and the rear side (right side in FIG. 1) roll unit 5a is rotationally driven counterclockwise.

Further, the shaft portions 5b and 5b of the pressure roll 5 are respectively guided in the front-rear direction by guide rails (not shown), and the positions of the both roll portions 5a and 5a are movable in directions close to and away from each other. .
That is, the gap dimension (dimension X shown in FIG. 1) between the two roll portions 5a and 5a can be easily changed. By changing the value of the dimension X, the thickness dimension of the laminated sheet 10 described later can be changed. It can be changed easily and with high accuracy.

An intermediate roll 6 is provided above the pressure roll 5.
The intermediate roll 6 includes two roll portions 6a and 6a and shaft portions 6b and 6b that respectively support the roll portions 6a and 6a via bearings (not shown). The intermediate roll 6 is between the extruders 4 and 4 and the pressure roll 5 with the axis of the roll portions 6a and 6a in the horizontal horizontal direction (horizontal direction orthogonal to the separating direction of the extruders 4 and 4). ) And facing each other in the front-rear direction (the separation direction of the extruders 4 and 4).

A bobbin 7 is provided above the intermediate roll 6.
The bobbin 7 is made of a cylindrical member, and a long film material 11 is wound around the outer peripheral surface thereof in advance.

Here, the film material 11 is a resin material having a function of preventing the permeation of fuel such as gasoline, for example, a barrier layer 11a made of ethylene vinyl alcohol (EVOH), polyamide, and the like, and anhydrous layers laminated on the front and back surfaces of the barrier layer 11a. It is configured as a three-layer film in which adhesive layers 11b and 11b made of a resin material such as maleic acid-modified polyethylene are laminated and adhered.
By forming a laminated sheet 10 to be described later using the film material 11 having such a configuration, the resin fuel tank 50 (see FIG. 4), which is a finished product, can easily have a function of preventing permeation of fuel such as gasoline. Can be included.

A through-hole 7a that penetrates along the axial center is provided at the center of the bobbin 7, and the bobbin 7 is freely rotatable via the support shaft 8 when the support shaft 8 penetrates into the through-hole 7a. Supported by
The support shaft 8 is provided parallel to the shaft portions 5b and 5b of the roll portions 5a and 5a of the pressure roll 5 and above the both roll portions 6a and 6a. The film material 11 to be unwound is disposed so as to be positioned between both roll portions 5a and 5a. The support shaft 8 has one end (for example, right end) fixed and held by a frame portion (not shown).

Further, the cross-sectional dimension of the through-hole 7 a of the bobbin 7 is somewhat larger than the cross-sectional dimension of the support shaft 8, and the bobbin 7 can be easily detached from the support shaft 8.
That is, even when all of the film material 11 wound around the bobbin 7 is drawn out during molding of the resin fuel tank 50 by the molding apparatus 1, the bobbin 7 that has been emptied by the operator's hand is removed from the support shaft 8. The bobbin 7 on which the film material 11 is wound again can be easily inserted into the support shaft 8 by being detached.

In this way, the laminating process unit 2 is provided with two extruders 4 and 4 facing each other in the front-rear direction, and the bobbin 7, the intermediate roll 6, and the pressure roll 5 are arranged on the lower side in that order from the top. It is configured.
Then, the two molten resin sheets 12 and 12 extruded from the dies 4a and 4a of the two extruders 4 and 4 hang down downward by their own weights, and then once obliquely downward through the intermediate roll 6. It is regulated and guided to the gap between the two roll portions 5a and 5a of the pressure roll 5. Further, the film material 11 fed out from the bobbin 7 also hangs downward due to its own weight, and is directly introduced into the gap between the two roll portions 5a and 5a of the pressure roll 5, and between the two molten resin sheets 12 and 12. It is designed to be pinched.

  That is, the film material 11 and the molten resin sheets 12 and 12 are placed on the pressure roll 5 in a state where the molten resin sheets 12 and 12 are arranged on the front surface (front surface) and the back surface (rear surface) with the film material 11 as the center. The film material 11 and the molten resin sheets 12 and 12 are laminated by passing through the gap between the roll parts 5a and 5a, and the laminated sheet is pressed while being handled by the both roll parts 5a and 5a. 10 is formed.

  And two sets of molding dies 20 and 20 which will be described later are provided below the laminating process section 2, and both the molding dies are formed while the molded laminated sheet 10 is suspended below the pressure roll 5. 20 and 20 are supplied.

Next, the structure of the shaping | molding process part 3 is demonstrated using FIG.
The molding process section 3 forms two molded bodies 23 and 23 (see FIG. 3) using the laminated sheet 10 supplied from the above-described lamination process section 2 and joins these molded bodies 23 and 23 to the final. This is a part for performing a process for molding a resin fuel tank 50 (see FIG. 4), which is a product, and is mainly constituted by two sets of molding dies 20 and 20.

  Each of the molding dies 20 includes a pair of concave molds 21 and a convex mold 22, and is formed on one side surface of the concave mold 21 and the convex mold 22. The concave portion 21a and the convex portion 22a are arranged to face each other in a state of being separated from each other by a predetermined dimension in the horizontal direction so as to be fitted to each other.

That is, as shown in FIG. 2 (a), each molding die 20 has a convex die 22 arranged on the front side in the horizontal front-rear direction so that the convex portion 22a protrudes rearward, and the rear side. The concave mold 21 is disposed so that the concave portion 21a is located on the front side.
The concave mold 21 and the convex mold 22 are guided by guide rails (not shown), respectively, and can move in the direction of approaching and separating from each other.

  Accordingly, the convex mold 22 is moved in the direction of the opposing concave mold 21, and the concave mold 21 is also moved in the direction of the opposing convex mold 22. The convex portion 22a and the concave portion 21a of the concave mold 21 are fitted to each other.

  In this way, two sets of molding dies 20 including a pair of concave dies 21 and convex dies 22 are provided below the laminating process unit 2, and lamination by these molding dies 20 and 20 is performed. When the press molding of the sheet 10 is completed and the two molded bodies 23 are formed, the concave mold 21 and the convex mold 22 are once moved in the front-rear direction so as to be separated from each other. .

  Thereafter, only the concave molds 21 and 21 of the molding dies 20 and 20 face each other with the concave parts 21a and 21a facing each other by, for example, a front-rear direction by a mold matching mechanism including a known moving mechanism and positioning mechanism. In this state, by moving the concave molds 21 and 21 in the front-rear direction so as to be close to each other and performing mold matching, the peripheral edge portions of the two molded bodies 23 and 23 are opened. The resin fuel tank 50, which is the final product, is joined to each other and molded.

[Molding procedure of resin fuel tank 50]
Next, the molding procedure of the resin fuel tank 50 using the molding apparatus 1 in the present embodiment will be described with reference to FIGS. For convenience, the vertical direction in FIG. 3 is defined as the vertical direction of the molding apparatus 1 and the direction of the arrow A is defined as the forward direction.

First, as shown in FIG. 1, as a first step, the molten resin sheets 12 and 12 are extruded downward in a sheet shape by the extruders 4 and 4, and the film material 11 wound around the bobbin 7 is also directed downward. It is drawn out.
Here, the molding conditions of the molten resin sheets 12 and 12 of the extruders 4 and 4 are set differently. More specifically, as will be described later, the molten resin sheet 12 extruded from the front extruder 4 is maintained at a high temperature so as to ensure the crimped state between the molded bodies 23 and 23, and the rear extruder 12 The molten resin sheet 12 extruded from 4 is set to be kept at a relatively low temperature with respect to the temperature of the molten resin sheet 12 extruded from the front extruder 4 in order to stabilize the molding shape by rapid cooling. ing.

  Then, above the pressure roll 5, the molten resin sheets 12 and 12 and the film material 11 are laminated so that the film material 11 is sandwiched between the two molten resin sheets 12 and 12. The film material 11 is pressure-bonded to the molten resin sheets 12 and 12 via the adhesive layers 11b and 11b by passing through the gaps between the two roll portions 5a and 5a of the pressure roll 5 while maintaining a simple state. Is formed.

Next, as shown in FIG. 2 (a), the laminated sheet 10 fed out from the pressure roll 5 as the second step is the convex molds 22 and 22 constituting the two sets of molding molds 20 and 20, respectively. , And the concave molds 21 and 21 are supplied in a suspended state.
At this time, first, the laminated sheet 10 is suspended between the convex mold 22 and the concave mold 21 constituting one molding mold 20, and the laminated sheet 10 is formed by the convex mold 22 and the concave mold 21. (See FIG. 2 (b)), after which the molding die 20 that has started the press molding is separated from the position immediately below the pressure roll 5 by a known moving mechanism or the like. The molding die 20 is conveyed (set) to a position directly below the pressure roll 5 in a state where the concave die 21 and the convex die 22 are separated from each other.

  Then, the laminated sheet 10 is again suspended between the concave mold 21 and the convex mold 22 (see FIG. 2A), and press molding of the molding mold 20 is started.

  Here, in the two sets of molding dies 20 and 20 when set immediately below the pressure roll 5, the convex dies 22 and 22 are positioned on the front side, and the concave dies 21 and 21 are positioned on the rear side. Thus, each is arranged.

That is, the high-temperature molten resin sheet 12 extruded from the front extruder 4 is always directed to the side where the convex molds 22 and 22 are disposed, and is compared to the extrusion extruded from the rear extruder 4. The molten resin sheet 12 in the low temperature state is always directed to the side where the concave molds 21 and 21 are disposed.
In other words, the molten resin sheet 12 on the rear surface side (one surface side) of the laminated sheet 10 is disposed on the concave mold 21 side, and the molten resin sheet 12 on the front surface side (other surface side) is disposed on the convex mold 22. Will always be on the side.

Accordingly, the molded bodies 23 and 23 formed by the molding dies 20 and 20 are always formed by the molten resin sheet 12 whose opening side (inside of the resin fuel tank 50) is at a high temperature, and the protruding side (resin made). The outer side of the fuel tank 50 is formed by the molten resin sheet 12 in a relatively low temperature state.
In this case, the stacking process parts 2 and 2 may be respectively installed in the two molding dies 20 and 20, and the molded bodies 23 and 23 may be simultaneously molded by the two molding dies 20 and 20.

  Thereafter, when a predetermined set time elapses after the press molding is started, the molding dies 20 and 20 are each “opened”. That is, the concave molds 21 and 21 and the convex molds 22 and 22 constituting the molding molds 20 and 20 are moved so as to be separated from each other, and a laminated sheet as shown in FIG. It is restored to the initial state before 10 is supplied.

  Here, for example, the surfaces of the concave portions 21a and 21a of the concave molds 21 and 21 are slightly rougher than the surfaces of the convex portions 22a and 22a of the convex molds 22 and 22. When the molds 20 and 20 are “open”, the molded bodies 23 and 23 formed by press molding always remain in the recesses 21a and 21a of the concave molds 21 and 21.

  Thereafter, as a third step, as shown in FIG. 3 (a), only the concave molds 21 and 21 of both molding dies 20 and 20 face each other with the concave parts 21a and 21a facing each other by a mold matching mechanism. As shown in FIG. 3 (b), by moving the concave molds 21 and 21 in the front-rear direction so as to be close to each other, The molded bodies 23 and 23 that remain in the concave portions 21a and 21a of the concave molds 21 and 21 are pressure-bonded to each other, and the resin fuel tank 50 shown in FIG. 4 is molded.

As described above, both the molded bodies 23 and 23 have the opening sides (inside of the resin fuel tank 50) on the side of the molten resin sheet 12 in the high temperature state. If it puts together, in the opening peripheral part of both the molded objects 23 and 23, it will contact | adhere on the surface of the molten resin sheet 12 side of a high temperature state mutually.
Thereafter, the outer peripheral end members of both molded bodies 23 and 23 to be products are trimmed by a known method.

  As described above, in this embodiment, the barrier layer 11a has a function of preventing the permeation of fuel stored in the resin fuel tank 50, and the adhesive layers 11b and 11b are laminated on the front and back surfaces of the barrier layer 11a. The pressure roll 5 includes a plurality of three-layer film material 11 and molten resin sheets 12 and 12 that are extruded by two extruders 4 and 4 and are respectively disposed on the front and back surfaces of the film material 11. A laminated resin sheet 12 and 12 having characteristics different from those of the barrier layer 11 a are laminated on the front and back surfaces of the film material 11 by being pressure-bonded while passing through the gap between the roll parts 5 a and 5 a. -The first step of forming 10 and the laminated sheets 10 and 10 are respectively disposed between the concave molds 21 and 21 and the convex molds 22 and 22 that can be fitted to each other, and the convex mold Type 22 ・ 22 A second step of forming the laminated sheets 10 and 10 into shaped bodies 23 and 23 having a predetermined concave shape by press-molding the laminated sheets 10 and 10 with the concave molds 21 and 21; The two concave molds 21, 21 holding the molded bodies 23, 23 formed in two steps are matched in the direction in which the concave shapes of the respective molded bodies 23, 23 face each other, and the molded body A third step of crimping and joining 23 and 23, and in the second step, the molten resin sheet 12 on one surface side of the laminated sheets 10 and 10 is disposed on the concave mold 21 and 21 side, A resin fuel tank (resin container) 50 is formed by a forming method in which the molten resin sheet 12 on the surface side is disposed on the convex molds 22 and 22 side.

  By using such a molding method, the molding apparatus 1 has a plurality of different functions such as a permeation prevention function of gasoline or the like and a strength maintenance function of a resin fuel tank (resin container) 50, for example. Without having a complicated mold structure, it is possible to mold a resin fuel tank (resin container) 50 capable of reliably joining the peripheral edge of the opening.

That is, in the first step, by incorporating the film material 11 including the barrier layer 11a into the laminated sheet 10, in addition to the unique characteristics of the molten resin sheets 12 and 12, the characteristics of the molten resin sheets 12 and 12 are different. The characteristics of the film material 11 can also be added to the laminated sheet 10, and the resin fuel tank 50, which is a finished product, can be easily provided with a function of preventing the permeation of fuel such as gasoline.
The laminated sheet 10 can also have an oxygen permeation prevention function, a moisture permeation prevention function, and the like according to the type of the film material 11 to be incorporated.

  Moreover, when shape | molding the lamination sheet 10 at a 1st process, the temperature of the molten resin sheet 12 arrange | positioned at the one surface side of the film material 11 is set rather than the temperature of the molten resin sheet 12 arrange | positioned at the other surface side. When the laminated sheet 10 is supplied to the molding dies 20 and 20 in the second step while being held at a high temperature, the side of the molten resin sheet 12 held at a high temperature faces away from the concave dies 21 and 21. The molten resin sheet 12 held at a low temperature is supplied so that the side thereof faces the concave molds 21 and 21.

  Therefore, in the third step, by aligning the concave molds 21, 21 with each other, the opening peripheral portions of the molded bodies 23, 23 whose one side (the opposite side to the concave molds 21, 21) is in a high temperature state. They can be in close contact with each other.

As a result, there is no complicated mold structure such as separately providing heating means or heat insulation means, and the peripheral edges of the openings of both molded bodies 23 and 23 can be joined while being kept at a high temperature, and completed. It is possible to ensure the joining strength and airtightness at the joining portion of the resin fuel tank (resin container) 50 which is a product.
Further, the molten resin sheet 12 that forms the outside (the concave molds 21 and 21 side) of the resin fuel tank (resin container) 50 is formed by the molten resin sheet 12 that is always kept at a low temperature. In addition, a strength holding function is also provided.

Further, in the molding method according to the present invention, not only the thickness of the molded body 23 is regulated by the pair of concave molds 21 and the convex molds 22 that can be fitted to each other, but both the roll portions 5a of the pressure roll 5 are also controlled. -The thickness of the laminated sheet 10 itself can be regulated by changing the value of the gap dimension X of 5a.
Accordingly, the thickness of the finished resin fuel tank 50 can be made uniform with higher accuracy.

DESCRIPTION OF SYMBOLS 4 Extruder 5 Pressure roll 5a Roll part 10 Laminated sheet 11 Film material 11a Barrier layer 11b Adhesive layer 12 Molten resin sheet 20 Molding die 21 Concave die 22 Convex die 23 Molded body 50 Resin fuel tank

Claims (1)

The front and back surfaces of the three-layer film material having a barrier layer for preventing permeation of substances stored inside the resin container and an adhesive layer laminated on the front and back surfaces of the barrier layer had characteristics different from those of the barrier layer. A first step of laminating resin sheets and forming a laminated sheet;
By disposing the laminated sheet between a concave mold and a convex mold that can be fitted to each other, and press-molding the laminated sheet with the convex mold and the concave mold, A second step of forming the laminated sheet into a molded body having a predetermined concave shape;
A third part in which the two molded dies holding the molded body molded in the second step are matched in a direction in which the concave shapes of the molded bodies face each other, and the molded bodies are pressure-bonded to each other. Process,
With
In the second step, the molten resin sheet on one side of the laminated sheet is arranged on the concave mold side, and the molten resin sheet on the other side is arranged on the convex mold side.
A method for molding a resin container.

Images