JP7586015B2 - Vacuum forming method - Google Patents

Description

This disclosure relates to a vacuum forming method.

For example, as described in Patent Document 1, a vacuum forming method is known in which a sheet-like material in a softened state is attached to a mold having a desired uneven shape by vacuum suction and formed into a desired shape. Specifically, this vacuum forming method is carried out in the following procedure. First, the outer edge of the softened material is grasped by a clamp so that the material is horizontally flattened, and while keeping the position of the clamp fixed, the mold is moved vertically to align the material with the surface of the mold (hereinafter referred to as the "molding part"), and then the material is attached to the molding part by vacuum suction. In this way, the material is molded while being stretched to fit the unevenness of the molding part.

JP 2001-301018 A

However, in the procedure for the vacuum forming method described above, the position of the clamping part is fixed, so depending on the shape of the mold, the position of the clamping part may move significantly away from the mold during or after forming. In this case, the material stretches significantly, resulting in a problem that the thickness of the molded product is smaller than expected and the strength is reduced.

The present disclosure can be realized in the following forms.
[Mode 1] A vacuum forming method for vacuum forming a sheet-like material using a forming mold, comprising: a gripping step of gripping an edge of the material with a gripping device; a moving step of moving the gripping device along a forming portion formed on a surface of the forming mold so that the material is arranged along the shape of the forming portion; and a bonding step of reducing the pressure between the forming portion and the material in a state in which the material is arranged along the shape of the forming portion by the moving step, thereby bonding the material to the forming portion. The forming portion includes a first forming portion and a second forming portion having a surface that is continuous with the first forming portion and intersects with the surface of the first forming portion, and further comprising a covering step of covering the first forming portion with the material. a moving step of moving the gripping device along the second molding portion while the first molding portion is covered with the material, and a step of adhering the material to the first molding portion and the second molding portion by reducing the pressure between the molding portion and the material while the material is arranged along the second molding portion, the second molding portion including a protruding undercut molding portion that forms an undercut, and the moving step of moving the gripping device in an intersecting direction that intersects with the surface of the first molding portion along the shape of the undercut molding portion, and the gripping device after the movement is in a position that overlaps with the undercut molding portion when viewed in the intersecting direction.

(1) According to one aspect of the present disclosure, there is provided a vacuum forming method for vacuum forming a sheet-like material using a forming mold, the vacuum forming method including a gripping step of gripping an edge of the material with a gripping device, a moving step of moving the gripping device along a forming portion formed on a surface of the forming mold so that the material is arranged along the shape of the forming portion, and a contact step of reducing pressure between the forming portion and the material to contact the material with the forming portion in a state in which the material is arranged along the shape of the forming portion by the moving step.
According to this embodiment, in the moving step, the gripping device gripping the edge of the material moves along the shape of the molding part, so that the material can be arranged roughly along the unevenness of the molding part. Then, with the material arranged along the shape of the molding part, the pressure is reduced between the molding part and the material, so that the material adheres to the molding part. In other words, since the position of the gripping device during and after molding is along the molding die, the position of the gripping device during and after molding does not move far away from the molding die, and the elongation of the material can be reduced, compared to, for example, a form in which the gripping device is fixed and the molding die is moved to make the material follow the shape of the forming surface. In other words, by suppressing the elongation rate of the material, the plate thickness of the molded product can be secured, and a decrease in strength can be suppressed.
(2) In the above embodiment, the molding portion includes a first molding portion and a second molding portion that is continuous with the first molding portion and has a surface that intersects with a surface of the first molding portion, and further includes a covering process for covering the first molding portion with the material, and in the moving process, the gripping device is moved along the second molding portion with the first molding portion covered with the material, and in the adhesion process, the pressure is reduced between the molding portion and the material with the material arranged along the second molding portion to adhere the material to the first molding portion and the second molding portion.
According to this embodiment, in the covering step, the first molded portion is covered with the material. Then, in the moving step, the gripping device is moved along the second molded portion that is continuous with the first molded portion and intersects with the first molded portion, so that the material can be aligned with the second molded portion. Therefore, in the vacuum molding method using a mold having the first molded portion and the second molded portion, the elongation rate of the material can be suppressed.
(3) In the above embodiment, the second molding portion may include a protruding undercut molding portion that forms an undercut, and the moving step may include a step of moving the gripping device in a cross direction that crosses the surface of the first molding portion along the shape of the undercut molding portion, and the gripping device after the movement may be in a position overlapping with the undercut molding portion when viewed in the cross direction. According to this embodiment, the elongation rate of the material can be suppressed even in a vacuum molding method having an undercut molding portion in which the elongation rate of the material is likely to be large.

1A to 1C are process diagrams illustrating a vacuum forming method according to a first embodiment of the present disclosure. 1 is a perspective view showing a schematic configuration of a vacuum forming apparatus according to a first embodiment of the present disclosure. 1 is a perspective view showing a schematic configuration of a vacuum forming apparatus according to a first embodiment of the present disclosure. FIG. 2 is a cross-sectional view of the vacuum forming apparatus, showing a gripping process. FIG. 2 is a cross-sectional view of the vacuum forming apparatus, showing a moving process. FIG. 2 is a cross-sectional view of the vacuum forming apparatus, showing a moving process. FIG. 11 is a side view of a vacuum forming apparatus according to another embodiment, illustrating a moving process.

A. First embodiment:
A1. Outline of the vacuum molding method and configuration of the vacuum molding device:
A vacuum forming method according to a first embodiment of the present disclosure will be described with reference to FIGS. 1 to 6. In the vacuum forming method according to the first embodiment, a vacuum forming apparatus 100 is used to integrally form a roof panel and an upper portion of a side outer panel for an automobile using a resin sheet for vacuum forming (hereinafter, also simply referred to as "material W"). The resin sheet as the sheet-like material W is, for example, a thermoplastic resin. As the thermoplastic resin, specifically, for example, polycarbonate (PC) resin, AES resin, ABS resin, PC/PET resin, polypropylene (PP) resin, etc. can be used, but the thermoplastic resin is not limited thereto and can be appropriately selected according to the desired molded product. The thickness of the resin sheet can be, for example, about 1 MM.

Figure 1 is a process diagram showing a vacuum forming method according to a first embodiment of the present disclosure. As shown in Figure 1, the vacuum forming method according to the first embodiment includes a covering process P10, a gripping process P20, a moving process P30, and a bonding process P40, which are carried out in this order. First, the schematic configuration of a vacuum forming device 100 used to carry out each of the processes P10, P20, P30, and P40 will be described. Then, each of the processes P10, P20, P30, and P40 will be described in order.

Figures 2 and 3 are perspective views showing the schematic configuration of a vacuum forming device 100 that performs the vacuum forming method. Figure 2 shows the state before forming, before gripping the material W, so the clamping member 50 described below is not shown. Figure 2 also shows the state in which the gripping device 2 described below is in the uppermost position. Figure 3 shows the state after forming, when the gripping device 2 is in the lowermost position.

In Figures 2 and 3, the XYZ coordinate system is used for the convenience of explaining the positional relationship of the components. XYZ are mutually orthogonal. The X-axis and Y-axis are axes along a horizontal plane, i.e., the XY plane is a horizontal plane. The Z-axis is an axis along a vertical line. The +Z-axis direction is the vertical upward direction, and the -Z-axis direction is the vertical downward direction. Hereinafter, the +Z-axis direction is also referred to as "up" and the -Z-axis direction is also referred to as "down". The +X-axis direction is also referred to as "left" and the -X-axis direction is also referred to as "right". The +Y-axis direction is also referred to as "rear" and the -Y-axis direction is also referred to as "front".

As shown in Figures 2 and 3, the vacuum forming apparatus 100 comprises a forming die 1, a gripping device 2 (an outer frame member 30 and a clamp member 50 (see Figure 3)), and guide plates 11, 12, 13, and 14. In the vacuum forming apparatus 100, each component is configured approximately symmetrically with respect to a center line C that extends in the Y-axis direction throughout the entire apparatus. The forming die 1 has a convex shape that protrudes upward, with the front and rear end areas gradually lower than the area near the center. The forming die 1 is long from front to back in a plan view, and is roughly rectangular.

A first molded portion 15 and a second molded portion 16 are formed on the surface of the mold 1. The first molded portion 15 is formed on the upper surface of the mold 1. The second molded portion 16 is formed on the side surface of the mold 1. The second molded portion 16 has a surface that is continuous with the first molded portion 15 and intersects with the surface of the first molded portion 15. In this embodiment, the second molded portion 16 is approximately perpendicular to the first molded portion 15. In this embodiment, "intersecting surfaces" means that the ends of the two surfaces are in contact with each other and that virtual surfaces obtained by extending each surface intersect with each other. Each molded portion 15, 16 corresponds to the shape of the molded product to be shaped, the first molded portion 15 corresponds to the shape of the roof panel, and the second molded portion 16 corresponds to the shape of the upper part of the side outer panel. The second molded portions 16 are arranged on the left and right sides of the first molded portion 15 in the X-axis direction. In Figures 2 and 3, only the second molded portion 16 on the left side is shown.

Figure 4 is a cross-sectional view of the vacuum forming device 100, and shows the gripping process P20. Figure 4 is a cross-sectional view of the device 100 in a vertical plane parallel to the XZ plane near the center in the Y-axis direction (front-back direction), and corresponds to the IV-IV arrow view shown in Figure 2. Note that the clamping member 50 and the material W are not shown in Figure 2, but the clamping member 50 and the material W are shown in Figure 4. As shown in Figure 4, the second forming section 16 has a protruding section 17 that protrudes outward and an undercut forming section 18 that is continuous with the tip of the protruding section 17 and is recessed inward. The undercut forming section is a section that forms the undercut of the product. The lower part of the undercut forming section 18 descends almost straight. Note that the forming mold 1 has a large number of suction holes (not shown) that penetrate the forming sections 15 and 16, and the air near the forming sections 15 and 16 can be sucked into the inside of the forming mold 1 through these suction holes.

Refer to Figures 2 and 3 again. The gripping device 2 is a device for gripping the outer peripheral end of the material W. The gripping device 2 is composed of an outer frame member 30 and a clamp member 50. The material W is gripped between the outer frame member 30 and the clamp member 50. The outer frame member 30 is provided so as to surround the four sides of the outer edge of the mold 1. The outer frame member 30 is composed of a front frame 31, a rear frame 32, a left frame 33, and a right frame 34 each having a substantially plate-like shape. The front frame 31 is arranged along the X-axis direction and along the front end surface of the mold 1. The rear frame 32 is arranged along the X-axis direction and along the rear end surface of the mold 1. The left frame 33 is arranged along the Y-axis direction and along the left end surface of the mold 1. The right frame 34 is arranged along the Y-axis direction and along the right end surface of the mold 1. The upper surfaces of the front frame 31 and the rear frame 32 are generally flat. The lower parts of the left frame 33 and the right frame 34 each protrude outward away from the mold 1, and as shown in FIG. 4, their vertical cross sections are L-shaped.

The upper surfaces of the left and right frames 33 and 34 have the highest Z-axis coordinate value at the center in the Y-axis direction. More specifically, the upper surfaces of the left and right frames 33 and 34 have the highest center in the front-to-rear direction, and the front and rear end portions are gradually lower than the center. Two guide rods 35, 36 are provided at the front end of the lower part of the left and right frames 33 and 34, protruding forward. Similarly, two guide rods 35, 36 are provided at the rear end of the lower part of the left and right frames 33 and 34, respectively, protruding rearward. The protruding tips of each guide rod 35, 36 engage with guide grooves 37, 38 of guide plates 11, 12, 13, and 14, which will be described later. Of the two guide rods 35, 36, the inner guide rod 35 closer to the mold 1 is provided at a higher position than the outer guide rod 36.

2 and 4, in the initial position before molding, the upper surface of the outer frame member 30 is higher than the upper surface of the mold 1. In addition, in the initial position before molding, a gap is formed between the right side surface of the left frame 33 and the left side surface of the mold 1 (second molding portion 16). Similarly, in the initial position before molding, a gap is formed between the left side surface of the right frame 34 and the right side surface of the mold 1. After molding, the right and left frames 33 and 34 move inward, and this gap disappears as shown in FIG. 6. Details will be described later in the molding method. Note that no gap is formed between the front frame 31 and the front surface of the mold 1, and between the rear frame 32 and the rear surface of the mold 1.

As shown in FIG. 3, the clamp member 50 is a member provided above the outer frame member 30 when gripping the material W, and is composed of clamps 51, 52, 53, and 54 corresponding to each frame 31, 32, 33, and 34, respectively. The clamp member 50 is composed of a front clamp 51, a rear clamp 52, a left clamp 53, and a right clamp 54. The outer frame member 30 and the corresponding clamp member 50 constitute the gripping device 2. That is, the front frame 31 and the front clamp 51 constitute the front gripping section 21. The rear frame 32 and the rear clamp 52 constitute the rear gripping section 22. The left frame 33 and the left clamp 53 constitute the left gripping section 23. The right frame 34 and the right clamp 54 constitute the right gripping section 24.

Hereinafter, when there is no need to distinguish between the gripping sections 21, 22, 23, and 24, they will be collectively referred to simply as the "gripping device 2." When there is no need to distinguish between the frames 31, 32, 33, and 34, they will be collectively referred to simply as the "outer frame member 30." When there is no need to distinguish between the clamps 51, 52, 53, and 54, they will be collectively referred to simply as the "clamp member 50."

Each of the clamps 51, 52, 53, and 54 is block-shaped. The shape of the upper surface of the outer frame member 30 corresponds to the shape of the lower surface of the corresponding clamp member 50. Therefore, with the material W interposed between the upper surface of the outer frame member 30, the clamp member 50 can be placed along the upper surface of the outer frame member 30 from above the material W. When gripping the material, the material W is sandwiched between the upper surface of the outer frame member 30 and the lower surface of the clamp member 50, and the outer frame member 30 and the clamp member 50 are fixed with bolts or the like (not shown), thereby gripping the material W.

The guide plates 11, 12, 13, and 14 guide the right and left gripping parts 23 and 24 in the movement process P30 and move them along a predetermined trajectory. The guide plates 11, 12, 13, 14, and 15 are provided at the front and rear ends of the left and right frames 33 and 34. The first guide plate 11 is provided at the front end of the left frame 33. The second guide plate 12 is provided at the rear end of the left frame 33. The third guide plate 13 is provided at the front end of the right frame 34. The fourth guide plate 14 is provided at the rear end of the right frame 34.

Since each guide plate 11, 12, 13, 14 has the same configuration, the second guide plate 12 will be described as an example with reference to FIG. 4. Two guide grooves 37, 38 are formed in parallel on the second guide plate 12. The guide grooves 37, 38 are substantially J-shaped when viewed from the -Y axis direction, and after descending substantially vertically from the upper end, they bend inward toward the mold 1 and continue to extend horizontally inward. Of the two guide grooves 37, 38, the inner guide groove 37 closer to the mold 1 is positioned higher than the outer guide groove 38. The tips of the guide rods 35, 36 can engage with the guide grooves 37, 38.

The mold 1 and each guide plate 11, 12, 13, 14 are fixed in a fixed position, and the gripping parts 21, 22, 23, 24 (outer frame member 30 and clamp member 50) are capable of moving relative to the mold 1 and each guide plate 11, 12, 13, 14 while gripping the material W. The details of the operation will be described later.

The vacuum forming apparatus 100 further includes a heating device and a vacuum pump (not shown). The heating device is for softening the material W, and may be, for example, a mid-infrared heater or a far-infrared heater. Heaters for heat retention are embedded inside the mold 1 and the outer frame member 30. By operating the vacuum pump, the material W can be brought into close contact with the unevenness of the forming part through the suction holes (not shown). The vacuum forming apparatus 100 is provided with a cylinder (not shown) that guides the movement of the front gripping part 21 and the rear gripping part 22 in the Z-axis direction.

A2. Details of the vacuum forming method:
Next, a description will be given of a vacuum forming method using the above-mentioned vacuum forming apparatus 100. First, in a covering step P10 (see FIG. 1 ), a material W is placed on the forming die 1 and the outer frame member 30 from above so as to cover the entirety including the forming die 1 and the outer frame member 30.

Next, in the gripping process P20, the outer peripheral edge of the material W placed on the outer frame member 30 is clamped between the upper surface of the outer frame member 30 and the lower surface of the clamp member 50, and the material W is fixed by tightening with a fixing member such as a bolt (not shown). At this time, as shown in FIG. 4, the gripping parts 21, 22, 23, 24 are at the upper end position, and the material W is fixed to the gripping parts 21, 22, 23, 24. In addition, the guide rods 35, 36 are located at the upper ends of the guide grooves 37, 38 with which they engage.

Next, in the movement process P30, the gripping device 2 is moved along the shape of the second molding portion 16 so that the material W is arranged along the shape of the second molding portion 16. Note that the term "arranged along" the shape of the second molding portion 16 does not necessarily mean that the material W is arranged along the shape of the second molding portion 16 at a constant distance, but has a broader meaning including a configuration in which the material W is arranged so that the outer shape of the material W is roughly similar or similar to the outer shape of the second molding portion 16, even though the distance between the second molding portion 16 and the material W is not constant.

During the moving process P30, a movable heating device (not shown) is operated to heat and soften the material W. Once the material W has softened, the heating device is turned off. The heating device may continue to operate during the moving process P30. Figures 5 and 6 are cross-sectional views of the vacuum forming device 100 and show the moving process P30. Figure 5 shows a state midway through the movement, and Figure 6 shows a state after further movement from the state shown in Figure 5, with the gripping device 2 at the lower end. Figure 6 corresponds to the view seen from the arrows VI-VI shown in Figure 3.

In this embodiment, the four gripping parts 21, 22, 23, and 24 are lowered simultaneously by, for example, multiple workers manually. At this time, assuming that the upper end position is the initial position, the left gripping part 23 gradually moves in the -X-axis direction while moving in the -Z-axis direction from the initial position shown in FIG. 4 as the guide rods 35 and 36 move down along the guide grooves 37 and 38 as shown in FIG. 5 and FIG. 6. The right gripping part 24, which operates symmetrically to the left gripping part 23, similarly moves in the -Z-axis direction while gradually moving in the +X-axis direction as the guide rods 35 and 36 move down along the guide grooves 37 and 38. At this time, the front and rear gripping parts 21 and 22 are lowered at the same speed as the left and right gripping parts 23 and 24 are lowered at the same speed as the left and right gripping parts 23 and 24. The front and rear gripping parts 21 and 22 are guided to move straight down in the -Z-axis direction along a cylinder not shown.

That is, the left and right gripping parts 23, 24 move gradually inwardly toward the mold 1 as they descend. At this time, the left and right gripping parts 23, 24 are guided by the guide grooves 37, 38, so their trajectories match the shape of the guide grooves. The operator only has to operate the guide rods 35, 36 to lower them, and the left and right gripping parts 23, 24 are automatically moved in the X-axis direction as well. In this way, the left and right gripping parts 23, 24 move two-dimensionally in the XZ plane along the shape of the second molding part 16 of the mold 1. Two-dimensional movement means that in the XZ plane as viewed from the Y-axis direction, they do not only descend in a straight line in the Z-axis direction, but also follow a trajectory that changes their position in the X-axis direction.

The provision of two guide rods 35, 36 allows the gripping device 2 to be kept horizontal when the guide rods 35, 36 move within the guide grooves 37, 38. The front and rear gripping parts 21, 22 move one-dimensionally in the -Z axis direction.

As shown in FIG. 6, when the left and right gripping parts 23, 24 reach the lowering end position, that is, after the moving process P30, the gap between the left and right gripping parts 23, 24 and the second molding part 16 is almost eliminated. The positions of the gripping parts 23, 24 after the moving process P30 are overlapped with the overhanging part 17 and the undercut molding part 18 when viewed in the Z-axis direction. That is, the moving process P30 includes a process of moving the gripping device 2 in a cross direction that crosses the surface of the first molding part 15 along the shape of the undercut molding part 18, and the gripping device 2 after the movement is overlapped with the undercut molding part 18 when viewed in the cross direction. The "cross direction" coincides with the Z-axis direction in this embodiment. In other words, the positions of the gripping parts 23, 24 after the moving process P30 are closer to the mold 1 than the protruding tip, which is the boundary between the overhanging part 17 and the undercut molding part 18.

In addition, a sealing member (not shown) is provided on the second molding portion 16 of the mold 1 facing the outer frame member 30, so that no gap is formed between the mold 1 and the outer frame member 30 after it has been moved.

Next, in the adhesion process P40, with the material W positioned along the second molding section 16, a vacuum pump (not shown) is operated to suction (vacuum drawing) through a suction hole (not shown) to reduce the pressure in the space between the molding sections 15, 16 and the material W. As a result, the material W is attracted to the first molding section 15 and the second molding section 16 and is drawn into the undercut molding section 18 while adhering thereto, and is shaped into the specified product shape.

According to the vacuum forming method of the first embodiment, in the moving step P30, the gripping device 2 (gripping parts 21, 22, 23, 24) gripping the outer peripheral edge of the material W moves, so that the material W can roughly conform to the uneven shape of the second molding part 16. Then, in the adhesion step P40, the material W is vacuumed while being arranged along the shape of the second molding part 16. In other words, since the position of the gripping device 2 during and after molding conforms to the second molding part 16, the difference between the length of the original material W and the length of the material W after molding can be reduced compared to, for example, a form in which the gripping device 2 remains fixed and the mold 1 moves to make the material W conform to the surface shape of the second molding part 16. In other words, by suppressing the elongation rate of the material W, the plate thickness as a molded product can be secured and strength reduction can be suppressed.

In addition, if the plate thickness becomes small, the required performance of the product may not be met, or the paint applied to the material W in advance may crack, making it difficult to ensure the quality of the product, which may result in a decrease in yield. In this regard, in the first embodiment, the elongation rate is suppressed, making the plate thickness uniform, thereby improving quality and increasing yield.

B. Other embodiments:
(B1) In the above first embodiment, the left and right gripping parts 23, 24 are moved in the moving step P30 so that the material W is aligned with the second molding portion 16 of the molding die 1, but this operation can be modified in various ways. For example, if the left and right gripping parts 23, 24 can be moved so as to be aligned with the second molding portion 16, the guide rods 35, 36 and the guide grooves 37, 38 may not be necessary.

(B2) Alternatively, a guide member and a guide wire may be used as another configuration. FIG. 7 is a side view of a vacuum forming apparatus 101 in another embodiment, and shows the moving process P30. Note that FIG. 7 is a schematic diagram for explaining a configuration for guiding the trajectories of the left and right gripping parts 23, 24, and the mold 1 is omitted. For example, as shown in FIG. 7, instead of providing guide plates 11, 12, 13, 14, a plate-shaped guide member 61 may be provided in front of and behind the mold 1, and the guide member 61 and the gripping parts 23 may be connected by a guide wire 62. The side surface 63 of the guide member 61 roughly corresponds to the shape of the molding part.

In the movement process P30, the guide wire 62 is tensioned and the gripping portion 23 is lowered in a trajectory as shown by the arrow A1, so that the guide wire 62 follows the side surface 63 of the guide member 61 and the gripping portion 23 is lowered along the shape of the guide member 61. As in this embodiment, the guide wire 62 may restrict the gripping portion 23 from moving in the +X-axis direction in which the material W stretches.

(B3) The mechanism for moving the gripping device 2 may be not only a mechanical and manual mechanism as described above, but may also employ a method in which the trajectories of the gripping parts 21, 22, 23, and 24 are automatically controlled by a computer using a motor or the like.

(B4) Also, in movement step P30, the mold 1 may be moved in the Z-axis direction and the gripping device 2 may be moved in the X-axis direction so that the material W is positioned along the mold 1. In other words, the movement of the mold 1 in the Z-axis direction and the movement of the gripping device 2 in the X-axis direction may be combined, resulting in the left and right gripping parts 23, 24 moving two-dimensionally along the shape of the second molding part 16 of the mold 1 in the XZ plane.

(B5) The trajectory of the left and right gripping parts 23, 24 in the moving process P30 can also be changed in various ways. For example, the left gripping part 23 can be lowered once and then raised again along a separately provided auxiliary die, or moved in the -X axis direction and then moved again in the +X axis direction to form the desired product shape. If there is a seal structure that seals between the outer frame member 30 and the molding die 1 after the moving process P30 is completed, the subsequent adhesion process P40 can be performed in the same manner as in the first embodiment described above.

(B6) The shapes of the outer frame member 30 and the clamp member 50 in the first embodiment are just examples, and various shapes are possible as long as they can grip the vicinity of the edge of the material W. Therefore, the shapes of the left frame 33 and the right frame 34 in the first embodiment may be a simple rectangular parallelepiped shape or may be flat plate-like members.

(B7) In the first embodiment, the left and right gripping parts 23, 24 are moved, but depending on the shape of the product to be formed, only one of the right or left gripping parts may be moved.

(B8) In addition, the undercut molding portion 18 is formed in the second molding portion 16 of the molding die 1, but depending on the product shape to be formed, the undercut molding portion 18 may not be formed.

(B9) In the first embodiment, the outer frame member 30 is fixed to the mold 1, but the outer frame member 30 may be separate from the mold 1 without being fixed to the mold 1. In this case, for example, the outer frame member 30 and the clamp member 50, which are separate from the mold 1, may grip the material W and then be positioned to cover the first molding portion 15. Then, in the moving step P30, the gripping device 2 may be moved so as to follow the second molding portion 16. In other words, the order of the covering step P10 and the gripping step P20 can be appropriately changed depending on the configuration of the molding device 100 corresponding to the product.

(B10) In the first embodiment, the molding section is composed of a first molding section 15 and a second molding section 16. That is, although the molding sections are formed on multiple intersecting surfaces, depending on the product shape to be formed, the molding sections may be formed on only one surface. In such a configuration, the covering process P10 may be omitted. That is, one end and the other end of the material W may be clamped by a pair of gripping sections at a position off the relevant surface, and then one gripping section may be moved along the relevant surface while the other gripping section is fixed at a position off the relevant surface, and then a vacuum may be drawn between the material W and the relevant surface. In this configuration, the covering process P10 is omitted before the gripping process P20.

The present disclosure is not limited to the above-described embodiments, and can be realized in various configurations without departing from the spirit of the disclosure. For example, the technical features in each embodiment corresponding to the technical features in each form described in the Summary of the Invention column can be replaced or combined as appropriate to solve some or all of the above-described problems or to achieve some or all of the above-described effects. Furthermore, if a technical feature is not described as essential in this specification, it can be deleted as appropriate.

1...Mold, 2...Gripping device, 11...First guide plate, 12...Second guide plate, 13...Third guide plate, 14...Fourth guide plate, 15...First molding section, 16...Second molding section, 18...Undercut molding section, 21...Front gripping section, 22...Rear gripping section, 23...Left gripping section, 24...Right gripping section, 30...Outer frame member, 31...Front frame, 32...Rear frame, 33...Left frame, 34...Right frame, 35...Guide guide rod, 36...guide rod, 37...guide groove, 38...guide groove, 50...clamp member, 51...front clamp, 52...rear clamp, 53...left clamp, 54...right clamp, 61...guide member, 62...guide wire, 63...side, 100...vacuum forming device, 101...vacuum forming device, C...center line, P10...covering process, P20...holding process, P30...moving process, P40...adhesion process, W...material

Claims (1)

A vacuum forming method for vacuum forming a sheet-shaped material using a forming mold, comprising the steps of:
a gripping step of gripping an edge of the material with a gripping device;
a moving step of moving the gripping device along a molding portion formed on a surface of the mold so that the material is arranged along the shape of the molding portion;
a contact process in which the material is placed along the shape of the molding portion by the moving process, and the material is brought into contact with the molding portion by reducing pressure between the molding portion and the material;
Equipped with
The molding portion includes a first molding portion and a second molding portion having a surface that is continuous with the first molding portion and intersects with a surface of the first molding portion,
The method further includes a covering step of covering the first molding portion with the material.
In the moving step, the gripping device is moved along the second molding portion while the first molding portion is covered with the material,
In the adhesion step, a pressure is reduced between the molding part and the material in a state in which the material is arranged along the second molding part, so that the material is adhered to the first molding part and the second molding part,
The second molding portion includes a protruding undercut molding portion that forms an undercut,
A vacuum molding method, wherein the moving step includes a step of moving the gripping device in a cross direction intersecting the surface of the first molding portion along the shape of the undercut molding portion, and after the movement, the gripping device is in a position overlapping with the undercut molding portion when viewed in the cross direction .

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