JP2002307542A - Molding apparatus - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a container molding apparatus which can improve the appearance quality of the container by preventing the formation of a mold split line in the container when the container in which a recessed part has the structure of an undercut is molded. SOLUTION: The container molding apparatus 11 has a softening means 13 and a molding means 14, which are arranged in turn in the transfer direction of a sheet member 12. The sheet member 12 is softened by the softening means 13. The sheet member 12 is guided to a molding means 14. A part 31 to be molded, while being held between a fixed mold 21 and a movable mold 22, is drawn by ejecting compressed air from the side of the fixed mold 21 to the part 31 and expanded. A molding mold 25 is pressed to the drawn part 31 to stretch the part 31. In this way, the part 31 can easily be stretched smoothly and homogeneously.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a forming device for forming a concave portion in a sheet member.

[0002]

2. Description of the Related Art As a material in which a concave portion is formed in a sheet member, for example, there is a carrier tape. Carrier tape is
It is made from strip-shaped plastic sheets. The carrier tape is provided with a plurality of recesses for accommodating small electronic components and the like at predetermined intervals.

Conventionally, a forming apparatus for forming the above-mentioned concave portion includes, for example, a softening means having upper and lower heating plates capable of coming and going to and from a sheet, and a forming device having an upper die and a lower die which can be brought to and away from a sheet. Means. Holes are formed in the lower mold and the upper mold at opposing positions. For example, a mold having a molding surface is provided in the hole of the lower mold so as to be vertically movable. Further, in the forming apparatus, the sheet is provided so as to be transferable, and each means is sequentially arranged along the sheet transfer direction.

In the molding apparatus, molding is performed through the following steps. First, the plastic sheet is heated and softened by the softening means. Next, the sheet is transferred to the forming means, and the periphery of the portion to be formed of the sheet is clamped by the upper mold and the lower mold. Subsequently, a molding die is pressed against the molded portion, whereby the molded portion is extended, and a concave portion having a predetermined shape is molded.

[0005] Such a molding apparatus is not limited to the field of carrier tape, and is generally used when molding a concave portion.

[0006]

However, the above-mentioned prior art has the following problems. That is,
In the above technique, when a mold is pressed against the sheet, the sheet is not necessarily stretched uniformly. In particular, the vicinity of the sandwiched portion (the portion corresponding to the side wall of the concave portion) is easily stretched, so that the thickness of the molded portion (concave portion) is uneven. As a result, various inconveniences may occur.

The present invention has been made in view of the above-described problems, and provides a molding apparatus capable of suppressing a problem caused by uneven thickness in forming a concave portion in a sheet member. This is one of the main purposes.

[0008]

Means for Solving the Problems and Effects There will be described below characteristic means for achieving the above object. Also,
For each means, characteristic actions and effects will be described as necessary.

Means 1. What is claimed is: 1. A forming device for forming a concave portion in a sheet member, comprising: a softening means for softening at least a portion to be formed of the sheet member; and a ring around a portion to be formed of the sheet member passing through the softening means. And forming means for applying tension to the molded part and pressing a molding die against the molded part to extend the molded part to form a concave portion. Molding equipment.

According to the first aspect, at the time of forming the concave portion in the sheet member, at least the portion to be formed of the sheet member is softened by the softening means. Next, in a state where the periphery of the molded portion is clamped by the molding means, tension is applied to the molded portion that is easily stretched by the softening. Then, when the molding die is further pressed, the molded portion is extended, and the concave portion is molded. For this reason, compared to the case where the molding die is simply pressed, the expansion by the pressing can be performed smoothly and uniformly, and the molded portion can be expanded without uneven thickness. as a result,
Problems due to uneven thickness are suppressed. The sheet member may be made of a thermoplastic resin material.

Means 2. Softening means for softening the sheet member, for the sheet member that has passed through the softening means,
A forming device for forming a concave portion, wherein the forming device includes a holding mechanism capable of holding a periphery of a portion to be formed of the sheet member in an annular shape, and the sheet member including the holding member. A tension applying mechanism for applying tension to the molded part in a state of being sandwiched, and an extension mechanism for extending the molded part by pressing a molding die against the molded part with the tension applied. A molding apparatus comprising:

According to the means 2, the sheet member is softened by the softening means, and the concave portion is formed by the forming means. Now, in the forming means, the sheet member is held by the holding mechanism,
In this state, tension is applied to the molded portion of the sheet member by the tension applying mechanism. Then, in a state where the tension is applied, a molding die is pressed against the molded portion by an extension mechanism, and the molded portion is extended. For this reason, compared to the case where the mold is simply pressed, the stretching by the pressing is more easily and uniformly performed. As a result, the thickness of the obtained recess is not so uneven, and the problem due to the uneven thickness is suppressed.

Means 3. The molding apparatus according to claim 1 or 2, wherein the tension is applied by generating a pressure difference between the molding die side and the opposite side with the sheet member as a boundary.

[0014] According to the means 3, a tension is applied by applying pressure to the molded part due to a difference in air pressure. Since the pressure is evenly applied, the tension is evenly applied, and the molded portion is easily stretched more uniformly. As a result, the effect of the means 1 or 2 can be obtained more reliably.

Means 4. The pressure difference is 0.01 MPa
Means 3 characterized in that it is not less than 0.03 MPa.
The molding device according to claim 1.

Here, when the difference in air pressure is less than 0.01 MPa, almost no tension is generated, and it is difficult to perform smooth and uniform expansion. Also, the pressure difference is 0.03MP
If it is larger than a, the molded portion is unlikely to have a shape conforming to the molding die during elongation, so that the molding accuracy may be deteriorated. In addition, more preferably, the difference in air pressure is 0.01 MPa or more and 0.02 MPa or less.

Means 5. Softening means for softening the sheet member, for the sheet member that has passed through the softening means,
A forming device for forming a concave portion, wherein the forming device includes a holding mechanism capable of holding a periphery of a portion to be formed of the sheet member in an annular shape, and the sheet member including the holding member. In the sandwiched state, an expansion mechanism that expands the molded part by supplying a pressurized gas, and a molding die is formed on the molded part from the side where the pressurized gas is supplied in the expanded state. A molding apparatus comprising: an extension mechanism for extending the molded portion by pressing.

According to the means 5, the sheet member is softened by the softening means, and the recess is formed by the forming means. In the forming means, the sheet member is held by the holding mechanism. In this state, pressurized gas is supplied by the expansion mechanism, and the molded portion of the sheet member is expanded. The molding die of the extension mechanism is pressed against the molded part in the expanded state from the side to which the pressurized gas is supplied, and the molded part is extended. For this reason, when the mold is pressed, the extension is easily performed smoothly and uniformly. As a result, the thickness of the obtained recess is not so uneven, and the problem due to the uneven thickness is suppressed.

Means 6 The molding apparatus according to claim 5, wherein an amount of expansion by the expansion mechanism is larger than an amount of expansion by the expansion mechanism.

According to the means (6), the molded portion is not excessively stretched at the time of expansion by the expansion mechanism, and is reliably extended by the extension mechanism, so that the molded portion is easily extended uniformly. It is stretched without uneven thickness. As a result, the operation and effect of the means 5 are reliably achieved.

Means 7. 7. The molding apparatus according to claim 5, wherein a pressure difference between the expansion and the outside air is 0.01 MPa or more and 0.03 MPa or less.

Here, when the pressure difference is less than 0.01 MPa, expansion does not easily occur, and it is difficult to perform smooth and uniform expansion. On the other hand, if the pressure difference is larger than 0.03 MPa, the molded portion is unlikely to have a shape along the molding die during elongation, so that the molding accuracy may be deteriorated. In addition, more preferably, the pressure difference is 0.01 M
It is not less than Pa and not more than 0.02 MPa.

Means 8. The molding apparatus according to any one of means 1 to 7, wherein a pressurized gas is blown from a side facing the molding die at least at one time during a period in which the molding die is pressed. .

According to the means 8, the pressurized gas is blown from the side facing the molding die while being pressed by the molding die, that is, while the portion to be molded is being moved along the molding die. Thereby, the molded part is brought into close contact with the molding die. For this reason, a to-be-formed part can be made to follow a shaping | molding die reliably. As a result, it is possible to improve the molding accuracy of the obtained concave portion.

Means 9 The molding apparatus according to claim 8, wherein the pressure difference between the pressurized gas blown from the side facing the molding die and the outside air is 0.2 MPa or more and 0.5 MPa or less.

Here, when the pressure difference is less than 0.2 MPa, the force with which the molded part is pressed against the molding die may be weak, and it may be difficult for the molded part to reliably follow the molding die. On the other hand, if the pressure difference is larger than 0.5 MPa, the force with which the molded part is pressed against the mold may increase, and smooth and uniform stretching of the molded part may be hindered. More preferably, the pressure difference from the outside air is 0.2M
It is not less than Pa and not more than 0.3 MPa.

Means 10. The molding apparatus according to any one of means 1 to 9, wherein at least a temperature of the mold at the time of the pressing is set higher than a normal temperature and lower than a glass transition point of the sheet member.

According to the means 10, by setting the temperature of the molding die, it is possible to suppress the trouble caused by the transmission of heat between the molding die and the sheet member, and the sheet member is softened more than necessary. It will not be too hard or too hard. That is, when the molding die is pressed, the sheet member can reliably maintain a state where it is easily stretched. Further, since the temperature change of the mold due to heat transfer is suppressed, no problem is likely to occur even if the mold is repeatedly molded.

Means 11. The mold according to any one of claims 1 to 10, wherein the mold has a molding surface having at least a side wall surface corresponding to a side wall of the concave portion and a top surface corresponding to a bottom wall of the concave portion. The molding apparatus as described in the above.

According to the means (11), the operation and effect corresponding to the means (1) to (10) can be obtained also in the formation of the concave portion having the side wall and the bottom wall.

Means 12 The molding apparatus according to claim 11, wherein the molding surface includes an edge portion at a boundary between the side wall surface and the top surface.

According to the means 12, since the thickness of the molded portion is not so uneven, the portion corresponding to the edge portion is hardly bent or broken, and the desired edge shape can be reliably obtained. Can be

Means 13 At least a pair of molds having holes at a portion corresponding to the molded portion so that at least the molded portion is softened in the sheet member, the periphery of the molded portion can be clamped in a ring shape, A means for applying tension to the molded part by supplying a pressurized gas from one hole while being sandwiched by at least a pair of molds to expand the molded part, and the pressurized gas is supplied. Means for extending the molded part by pressing a molding die set at a temperature higher than room temperature and lower than the glass transition point of the sheet member from the side to the molded part; and Means for blowing a pressurized gas having a pressure higher than that at the time of the expansion from the side facing the molding die at least at one time during the pressing period.

According to the means 13, at least in the sheet member in which the molded portion is softened, the molded portion is sandwiched by the mold having the holes, so that the confidentiality around the molded portion is ensured. Thereby, tension can be reliably applied to the molded part, and the molded part can be reliably expanded. Further, a mold set at a temperature higher than the normal temperature and lower than the glass transition point of the sheet member is pressed against the molded portion from the side to which the pressurized gas is applied. At this time, during the contact between the molded portion and the molding die, the molded portion is not deprived or supplied with heat more than necessary. That is, when the molding die is pressed, the molded portion can reliably maintain an easily stretched state. In addition, when the pressing is performed in a state where the tension is applied, the stretch of the molded portion is performed more smoothly and uniformly, and the thickness does not become uneven. Further, since the temperature change of the mold due to heat transfer is suppressed, no problem is likely to occur even if the mold is repeatedly molded. Further, during the pressing period, a pressurized gas having a higher pressure than the expansion is blown from the side facing the molding die to the molded portion. This allows the molded part to be in close contact with the molding die, so that the molded part can be reliably aligned with the molding die. As a result, it is possible to improve the molding accuracy of the obtained concave portion.

[0035]

DESCRIPTION OF THE PREFERRED EMBODIMENTS One embodiment will be described below with reference to the drawings. First, the configuration of the carrier tape 1 as a product will be described with reference to FIG. The carrier tape 1 is made of a thermoplastic resin material such as polystyrene, and includes a base portion 2 having a flat surface and a plurality of recesses 3 recessed from the base portion 2 (in FIG. Status). The concave portion 3 has a bottom wall 32 and a side wall 33, and a boundary portion between these 32 and 33 is an edge portion. The recesses 3 are provided at predetermined intervals along the longitudinal direction of the carrier tape 1 so that small electronic components (not shown) can be accommodated therein.

The carrier tape 1 is formed by a forming device 11 shown in FIG. In the forming apparatus 11, a belt-shaped sheet member 12 is provided so as to be intermittently transported from right to left in the drawing. The sheet member 12 is a raw material of the carrier tape 1. The molding device 11 includes a softening unit 13 and a molding unit 14.
These means 13 and 14 are arranged in order along the transport direction of the sheet member 12. The softening means 13 includes, for example, an upper heater 15, an upper heating plate 16 heated by the upper heater 15, a lower heater 17, and the lower heater 17.
And a lower heating plate 18 that is heated by the heating device. Each of the heating plates 16 and 18 has heating projections 19 and 20 that are brought into contact with the sheet member 12, and has a temperature equal to or higher than the glass transition point and equal to or lower than the melting point of the sheet member 12 (for example, 150 ° C. in the present embodiment).
° C). The heating plates 16 and 18 can move together with the corresponding heaters 15 and 17 in a direction approaching and away from the sheet member 12, that is, in a vertical direction. The two heating plates 16 and 18 move in the approaching direction and are brought into contact with the sheet member 12 so that the sheet member 12 is heated and softened.

The forming means 14 includes a fixed mold 21 and a movable mold 22 provided at a position facing the fixed mold 21 with the sheet member 12 interposed therebetween. The fixed mold 21 has a hole 23 that opens to the sheet member 12 side. On the other hand, the movable mold 22 has holes 24 corresponding to the holes 23 of the fixed mold 21.
It has. Further, the movable mold 22 is relatively movable in the direction of contact and separation with the fixed mold 21, and the movable mold 22 is moved in the approaching direction, whereby the sheet member 12 is held. I have.

A molding die 25 is provided inside the hole 23 of the fixed die 21.
Are provided so as to be movable in the vertical direction in the figure. A medium (for example, water) at a predetermined temperature is circulated inside the molding die 25. Thereby, the mold 25 is maintained at a temperature not lower than the normal temperature and not higher than the glass transition point (for example, 45 ° C. in the present embodiment). A molding surface 26 for molding the recess 3 is formed on the upper part of the molding die 25.
(For example, in this embodiment, a front trapezoidal shape) is formed.

Each of the fixed mold 21 and the movable mold 22 is provided with a blow mechanism (not shown).
From the blow mechanism on the fixed mold 21 side, air as pressurized gas is supplied to the holes 23 of the fixed mold 21 and, consequently, the sheet member 12.
It is sprayed from the lower side of the figure, whereby a slight pressure TP is applied (see FIG. 3). On the other hand, the movable mold 2
Air as a pressurized gas is blown from the blow mechanism on the second side to the hole 24 of the movable mold 22 and, consequently, the sheet member 12 from above in the figure, whereby a predetermined pressure BP is applied (see FIG. 5). .

Next, a procedure for molding the carrier tape 1 as a product by using the molding apparatus 11 configured as described above, and the operation and effect at that time will be described.

First, the sheet member 12 is transferred to the softening means 13. In the softening means 13, the heaters 15, 17
The heating plates 16 and 18 heated by the
Is moved in a direction approaching. Then, the heating projection 19,
20 and the sheet member 12 come into contact with each other, and the molded portion 31 of the sheet member 12 is heated and softened. Subsequently, the heating plates 16 and 18 are moved in a direction away from the sheet member 12, and the sheet member 12 having the softened molded portion 31 is guided to the molding unit 14.

In the forming means 14, the sheet member 12
The movable mold 22 is moved in a direction approaching the fixed mold 21 with the. As a result, the molded part 31 is
The sheet member 12 is sandwiched between the fixed mold 21 and the movable mold 22 in a state where the sheet member 12 is aligned with the positions of the holes 23 and 24 of the mold 22. The molded part 31 has holes 23 and 24.
Is fixed between the fixed mold 21 and the movable mold 22 having
The confidentiality around the molded part 31 is improved.

Next, as shown in FIG. 3, in a state where the sheet member 12 is sandwiched, pressurized air is blown from a blow mechanism on the fixed die 21 side, and a slight pressure TP is applied to the molded portion 31. . In the present embodiment, the differential pressure between the minute pressure TP and the outside air is set to, for example, 0.01 MPa. Thereby, tension is applied to the molded part 31 and the molded part 31 is expanded.

Further, as shown in FIG.
The mold 25 is moved in the upward direction in the drawing while being tensioned, and is pressed against the molded part 31. Then
The molded part 31 is further extended from the expanded state. At this time, the expansion by pressing is performed smoothly and uniformly. In addition, the amount expanded by the pressing is larger than the amount expanded.

Further, as shown in FIG.
When 1 is pushed out, the blowing of the pressurized gas from the blow mechanism on the fixed mold 21 side is stopped. Concurrently, pressurized air is blown from the blow mechanism on the movable mold 22 side to the molded portion 31, whereby a predetermined pressure BP (for example, 0.2 MPa) is applied to the molded portion 31. Therefore, the molded portion 31 is securely brought into close contact with the molding surface 26, and the molded portion 31 can be reliably formed along the molding surface 26. Further, since the predetermined pressure BP is applied, the air between the molding die 25 and the molded portion 31 flows out smoothly, so that there is no need to provide an air vent hole in the molding die 25. Therefore, no trace of the hole is left in the concave portion 3 to be molded. As a result, the accuracy of molding is further improved, and the appearance quality of the concave portion 3 (the finally obtained carrier tape 1) is improved. be able to.

Thereafter, the blowing of the pressurized air from the blow mechanism on the movable mold 22 side is stopped, the mold 25 is moved downward, and the movable mold 22 is moved away from the fixed mold 21, whereby The above-described carrier tape 1 is obtained.

As described in detail above, according to the present embodiment, tension is applied to the molded part 31. For this reason, when pressed by the molding die 25, the molded portion 31 is smoothly and uniformly stretched as compared with a case where the molding die 25 is simply pressed. Therefore, the molded portion 31 is stretched without uneven thickness, and as a result, a problem due to uneven thickness can be suppressed.

Further, as in this embodiment, the molding surface 26
Is a front trapezoidal shape, the concave portion 3 having the bottom wall 32 and the side wall 33 can be reliably obtained. In particular, when the molded part 31 is stretched, a predetermined pressure BP is applied to the molded part 31, so that the edge part 34 at the boundary between the bottom wall 32 and the side wall 33 of the concave part 3 also bends. It is hard to be broken and a desired edge shape can be obtained.

Further, by setting the temperature of the molding die 25, the trouble caused by the transmission of heat between the molding die 25 and the molded part 31 is suppressed, and the state where the molded part 31 is easily stretched is reduced. It is surely kept. In addition, since a change in temperature of the mold 25 due to heat transfer is suppressed, a problem hardly occurs even when molding is repeated.

It should be noted that the present invention is not limited to the contents described in the above embodiment, and may be implemented as follows, for example.

(A) The material of the sheet member 12 is not limited to the polystyrene of the present embodiment, but may be a thermoplastic resin such as polyester, polypropylene, polyethylene, or polyamide.

(B) In the above embodiment, the carrier tape 1 has been described as a product, but the present invention is also applicable to, for example, molding a container for food or medicine.

(C) The shape of the recess 3 is not particularly limited. Therefore, it may have a curved surface. However,
This is particularly effective when forming the concave portion 3 having the edge portion as in the present embodiment.

(D) In the above embodiment, the softening means 13 is configured to directly contact the heating concave portions 19, 20 with the sheet member 12, but may be configured to heat and soften in a non-contact state.

(E) A plurality of heating projections 19 and 20, a plurality of holes 23 of the fixed mold 21, a plurality of holes 24 of the movable mold 22, and a plurality of molding dies 25 may be provided. Thus, a plurality of recesses 3 can be obtained at one time.

(F) In the above embodiment, the movable mold 22 is moved in the direction of approaching and separating from the fixed mold 21. However, both the upper and lower molds may be movable.

(G) In the above embodiment, the molded part 31
Although a blow mechanism is provided on the fixed mold 21 side to apply tension to the movable mold 22, the blow mechanism on the fixed mold 21 side is omitted, and an intake mechanism is provided on the movable mold 22 side to generate a negative pressure. A tension may be applied to the molding unit 31.

(H) If the required molding accuracy is obtained, the predetermined pressure BP applied to the molded part 31 when the molded part 31 is stretched may be omitted. In this case, the blow mechanism on the movable mold 22 side for applying the predetermined pressure BP may be omitted.

[Brief description of the drawings]

FIG. 1 is a cross-sectional view schematically illustrating a configuration of a molding apparatus according to an embodiment.

FIG. 2 is a partial perspective view of a carrier tape as a product.

FIG. 3 is a schematic cross-sectional view illustrating a forming process of a sheet member.

FIG. 4 is a schematic cross-sectional view illustrating a forming process of a sheet member.

FIG. 5 is a schematic cross-sectional view illustrating a forming process of a sheet member.

[Explanation of symbols]

DESCRIPTION OF SYMBOLS 1 ... Carrier tape, 3 ... recessed part, 11 ... Molding apparatus, 12
... sheet member, 13 ... softening means, 14 ... molding means, 16
... upper heating plate, 18 ... lower heating plate, 21 ... fixed type, 22
... movable mold, 25 ... molding mold.

 ──────────────────────────────────────────────────続 き Continuing on the front page (72) Inventor Sakai Ippiko 2-250 Otonoki, Komaki-shi, Aichi Prefecture Inside C-Caddy Co., Ltd. (72) Inventor Junji Masuda 250-250 Otonoki, Komaki-shi, Aichi C-Caddy Corporation F term (reference) 4F202 AG01 AG05 AM32 AR02 AR04 AR06 CA17 CB02 CK11 CK90 4F208 AC01 AG01 AG05 AM32 AR02 AR04 AR06 MA05 MB02 MB29 MC02 MH06 MK04 MK15

Claims (13)

[Claims] 1. A forming apparatus for forming a concave portion in a sheet member, comprising: a softening means for softening at least a portion to be formed of the sheet member; and a softening means for forming a portion of the sheet member through the softening means. In a state where the periphery is held in a ring shape, tension is applied to the molded part,
The molding apparatus further comprises molding means for pressing the molding die against the molded part to extend the molded part and form the concave part. 2. A forming apparatus comprising: softening means for softening a sheet member; and forming means for forming a recess in the sheet member having passed through the softening means, wherein the forming means comprises: A clamping mechanism capable of annularly clamping the periphery of the molded portion of the sheet member, a tension applying mechanism for imparting tension to the molded portion in a state where the sheet member is clamped by the clamping mechanism, and applying the tension. A molding device, comprising: a stretching mechanism that stretches the molded portion by pressing a molding die against the molded portion in a state where the molding is performed. 3. The molding apparatus according to claim 1, wherein the tension is applied by generating a pressure difference between the molding die side and the opposite side with the sheet member as a boundary. . 4. The molding apparatus according to claim 3, wherein the difference between the atmospheric pressures is 0.01 MPa or more and 0.03 MPa or less. 5. A forming apparatus comprising: softening means for softening a sheet member; and forming means for forming a recess in the sheet member having passed through the softening means, wherein the forming means comprises: A holding mechanism capable of holding the periphery of the formed portion of the sheet member in a ring shape, and an expansion mechanism for expanding the formed portion by supplying a pressurized gas while the sheet member is held by the holding mechanism. And an extension mechanism for extending the molded part by pressing a molding die against the molded part from the side to which the pressurized gas is supplied in the expanded state. Molding equipment. 6. The amount extended by the extension mechanism is:
The molding apparatus according to claim 5, wherein the amount is larger than an amount that can be expanded by the expansion mechanism. 7. The pressure difference from outside air at the time of the expansion is:
The molding apparatus according to claim 5, wherein the pressure is 0.01 MPa or more and 0.03 MPa or less. 8. The apparatus according to claim 1, wherein a pressurized gas is blown from a side facing the molding die at least at one time during a period in which the molding die is pressed. A molding device according to any one of the above. 9. The pressure difference between the pressurized gas blown from the side facing the molding die and the outside air is 0.2 MPa or more and 0.1 MPa or more.
The molding apparatus according to claim 8, wherein the pressure is 5 MPa or less. 10. The method according to claim 1, wherein a temperature of the mold at least at the time of the pressing is set higher than a normal temperature and lower than a glass transition point of the sheet member. The molding device according to claim 1. 11. The mold according to claim 1, wherein the mold has a molding surface having at least a side wall surface corresponding to a side wall of the concave portion and a top surface corresponding to a bottom wall of the concave portion. 11. The molding apparatus according to any one of claims 10 to 10. 12. The molding apparatus according to claim 11, wherein the molding surface has an edge portion at a boundary between the side wall surface and the top surface. 13. At least one pair of a sheet member having at least a molded portion softened, having a hole in a portion corresponding to the molded portion so as to be able to sandwich the periphery of the molded portion in a ring shape. Means for applying tension to the molded part by supplying pressurized gas from one hole while being sandwiched by the at least one pair of molds, thereby expanding the molded part; and From the side where gas is supplied, to the molded part,
Means for extending the molded part by pressing a mold set higher than normal temperature and lower than the glass transition point of the sheet member; and at least one time during a period in which the mold is pressed. , A means for blowing a pressurized gas having a higher pressure than that at the time of the expansion from a side facing the molding die.