Sheet material sticking device and sheet material sticking method

Abstract

A sheet material PT is sandwiched between an upper housing 20 and a lower housing 22A to form a chamber 17, and an abutment surface 95 of a deformation member 63 is brought into contact with the sheet material PT in the chamber 17, whereby the sheet material PT is deformed, and a protrusion V is formed. A differential pressure is generated within the chamber 17 in a state where the sheet material PT deformed by the deformation member 63 is brought close to or into contact with a curved surface Wb of a workpiece W, and the sheet material PT is stuck to the curved surface Wb by the differential pressure. The abutment surface 95 of the deformation member 63 is configured to have a curvature that is greater than the curvature of the curved surface Wb of the workpiece W.

Description

Sheet material joining device and sheet material joining method

[0001] The present invention relates to a sheet material joining device and a sheet material joining method used to join a sheet material, such as an adhesive tape or an adhesive film, to a workpiece having a curved surface.

[0002] Conventionally, flat wafers or substrates have been used as workpieces to which sheet materials for circuit protection, etc. are attached. However, in recent years, the shapes of workpieces have become more diverse, and there are cases where sheet materials are attached to curved surfaces of workpieces, such as concave surfaces.

[0003] When attaching a sheet material to a curved surface of a workpiece, the sheet material may wrinkle or air bubbles (voids) may be trapped between the workpiece and the sheet material due to the sheet material contacting the outer periphery of the curved surface first. For example, if the sheet material contacts the shallower recessed portion of the curved surface before contacting the deeper recessed portion in the center of the concave curved surface, wrinkles or air bubbles may be generated when the sheet material is attached to the entire curved surface of the workpiece. To avoid a decrease in the adhesion accuracy of the sheet material to the workpiece due to the occurrence of wrinkles or the inclusion of air bubbles, a sheet material attachment device that deforms the sheet material using a rod-shaped deformation member has been proposed (see Patent Document 1).

[0004] In such an apparatus, a rod-shaped protruding member is brought into contact with a portion of the sheet material inside a vacuum chamber, forming a protrusion that faces the curved surface of the workpiece. When the protrusion is formed, the protruding member is brought closer to the workpiece, bringing the protrusion into contact with, for example, a deep portion of the curved surface of the workpiece. A pressure difference is then created between the upper and lower spaces in the vacuum chamber separated by the sheet material, and the sheet material is attached to the curved surface of the workpiece so that it spreads outward from the portion where the protrusion contacts. In this case, the sheet material is attached first to the deep recessed portion of the workpiece, more reliably preventing the formation of wrinkles or air bubbles.

[0005] Japanese Patent Application Laid-Open No. 2020-188216

[0006] However, the above-mentioned conventional device has the following problem: when a sheet material is attached to a workpiece having a curved surface, it is difficult to make the sheet material exhibit uniform properties over the entire workpiece. In other words, it was found that the properties of the sheet material vary over the entire workpiece.

[0007] The following are possible causes of such variations in the characteristics of the sheet material. In the conventional configuration described in Patent Document 1, when a thin, rod-shaped protruding member is brought into contact with a portion of the sheet material to form protrusions, the sheet material in the portion where the protrusions are formed is stretched and thinned. In other words, the stretching rate of the sheet material significantly differs between the portion where the protrusions are formed and the portion where the protrusions are not formed. In the case of a sheet material, differences in the stretching rate can cause changes in the characteristics of the sheet material. In other words, the properties of the sheet material significantly differ between the area of ​​the workpiece to which the sheet material in the portion where the protrusions are formed and the area of ​​the workpiece to which the sheet material in the portion where the protrusions are not formed due to variations in the stretching rate. As a result, while the requirement of preventing wrinkles or bubbles can be met, it becomes difficult to meet the requirement of achieving uniform properties throughout the entire workpiece to which the sheet material is attached.

[0008] The present invention has been made in consideration of the above circumstances, and its main object is to provide a sheet material application method and sheet-like application device that can apply sheet material to a workpiece having a curved surface with high precision and reduce variation in the characteristics of the sheet material over the entire surface of the workpiece.

[0009] In order to achieve the above object, the present invention has the following configuration: A sheet material joining device for joining a sheet material to a curved surface of a workpiece, comprising: a holding table for holding the workpiece with the curved surface facing upward; an upper chamber and a lower chamber for sandwiching the sheet material, thereby dividing the sheet material into an upper space and a lower space via the sheet material, and a chamber for storing the holding table in the lower space; a supply mechanism for supplying the sheet material; a deformation member having an abutting surface and deforming the sheet material by bringing the abutting surface into contact with the sheet material; a deformation member moving mechanism for moving the deformation member close to the holding table while the deformation member is in contact with the sheet material, and bringing the sheet material deformed by the deformation member into close proximity to or abutting at least a portion of the curved surface of the workpiece; and a decompression mechanism for evacuating at least the lower space out of the upper and lower spaces. and a bonding mechanism that, while the lower space is evacuated and the sheet material is close to or abutting a portion of the curved surface of the workpiece, bonds the sheet material to the curved surface of the workpiece by the pressure difference formed between the upper space and the lower space in the chamber separated by the sheet material, wherein the curvature of the abutting surface of the deformable member is configured to be greater than the curvature of the curved surface of the workpiece.

[0010] (Operations and Effects) According to this configuration, a sheet material joining device for joining a sheet material to a curved surface of a workpiece having a curved surface includes a chamber and a deformation member. That is, the sheet material is sandwiched between the upper and lower chambers while the curved workpiece is held by the holding table, thereby dividing the interior space of the chamber into an upper space and a lower space via the sheet material. At this time, the holding table holding the workpiece is stored in the lower space of the chamber. The sheet material sandwiched between the upper and lower chambers is deformed by the contact surface of the deformation member coming into contact with the sheet material. The sheet material deformed by the deformation member approaches or abuts a portion of the curved surface of the workpiece, and is then joined to the curved surface of the workpiece by the differential pressure generated within the chamber.

[0011] In this case, the curvature of the contact surface of the deforming member is configured to be larger than the curvature of the curved surface of the workpiece. Therefore, when the sheet material deformed by the deforming member is attached to the curved surface of the workpiece, tension caused by the sheet material contacting an unexpected part, such as the edge of the workpiece, can be prevented. This tension can cause wrinkles and air bubbles to form when the sheet material is attached to the curved surface. Therefore, the formation of wrinkles and air bubbles in the sheet material attached to the curved surface of the workpiece can be prevented, allowing the sheet material to be adhered to the curved surface of the workpiece with precision.

[0012] Furthermore, by making the curvature of the contact surface of the deforming member larger than the curvature of the curved surface of the workpiece, the area of ​​the sheet material that contacts the contact surface and deforms is widened, thereby reducing the degree to which the sheet material stretches per unit area of ​​that area. As a result, the variation in the stretch rate of the sheet material is reduced throughout the entire sheet material that is attached to the curved surface of the sheet material workpiece, making it possible to achieve uniform properties throughout the entire workpiece to which the sheet material is attached.

[0013] In the above-described invention, the cross-sectional width a of the contact surface of the deformable member and the cross-sectional width b of the curved surface of the workpiece are It is preferable that the following condition is satisfied.

[0014] (Operation and Effect) According to this configuration, the cross-sectional width a of the contact surface of the deforming member and the cross-sectional width b of the curved surface of the workpiece are configured to satisfy the condition a ≥ 0.3 × b. By configuring the deforming member so that the cross-sectional width satisfies this condition, the area of ​​the sheet material that contacts the contact surface and deforms is further expanded, thereby reducing the degree of stretching of the sheet material per unit area of ​​that area. As a result, the variation in the stretch rate of the sheet material is reduced throughout the entire sheet material that is attached to the curved surface of the sheet material workpiece, making it possible to achieve uniform properties throughout the entire workpiece to which the sheet material is attached.

[0015] Furthermore, in the above-mentioned invention, it is preferable that an air pressure adjustment mechanism is provided that adjusts the air pressure in the lower space so that it is higher than the air pressure in the upper space, and when the air pressure adjustment mechanism adjusts the air pressure in the lower space so that it is higher than the air pressure in the upper space, the deformation member moving mechanism brings the sheet material deformed by the deformation member close to or into contact with at least a portion of the curved surface of the workpiece.

[0016] (Operations and Effects) With this configuration, by adjusting the air pressure in the lower space to be higher than that in the upper space, the sheet material can be more reliably separated from the workpiece. Therefore, during the process of deforming the sheet material with the deformation member and the process of bringing the deformed sheet material close to or into contact with the curved surface of the workpiece, it is possible to more reliably prevent the sheet material from unexpectedly contacting the periphery of the workpiece. This reliably prevents the occurrence of wrinkles, air bubbles, and the like that would result from unexpected contact between the sheet material and the workpiece, thereby further improving the accuracy of the sheet material's adhesion to the curved surface of the workpiece.

[0017] Furthermore, in the above-described invention, it is preferable that the bonding mechanism bonds the sheet material to the curved surface of the workpiece by using a pressure difference formed between an upper space and a lower space in the chamber separated by the sheet material, with the sheet material abutting against a portion of the curved surface of the workpiece.

[0018] (Operations and Effects) With this configuration, a pressure difference is generated after the portion of the sheet material deformed by the deformation member comes into contact with the curved surface of the workpiece. In this case, the timing at which the entire sheet material in the chamber is deformed by the pressure difference occurs reliably after the sheet material deformed by the deformation member comes into contact with the curved surface of the workpiece. This more reliably prevents a situation in which the portion of the sheet material other than the deformed portion unexpectedly comes into contact with the curved surface of the workpiece before the portion of the sheet material deformed by the deformation member comes into contact with the curved surface of the workpiece. This more reliably prevents the occurrence of wrinkles, air bubbles, and the like due to unexpected contact of the sheet material.

[0019] In the above-described invention, it is preferable that the deforming member has an elastic body on the contact surface, and that the sheet material is deformed by bringing the elastic body into contact with the sheet material.

[0020] (Functions and Effects) With this configuration, when the portion of the sheet material that has been deformed by the contact surface comes into contact with the curved surface of the workpiece, the elastic body provided on the contact surface elastically deforms appropriately in accordance with the shape of the curved surface of the workpiece. This elastic deformation prevents the pressing force exerted by the deforming member on the workpiece from becoming excessive when the deforming member moves toward the holding table that holds the workpiece. This more reliably prevents the workpiece from being deformed or damaged due to excessive pressing by the deforming member on the workpiece.

[0021] Furthermore, in the above-described invention, it is preferable that the workpiece has a concave curved surface, and the deformation member moving mechanism brings the sheet material deformed by the deformation member close to or into contact with an area including the deepest part of the concave curved surface.

[0022] (Operations and Effects) With this configuration, the portion of the sheet material deformed by the deforming member is adjacent to or abuts against a region including the deepest portion of the concave curved surface of the workpiece. In conventional configurations, the deepest portion of the concave curved surface is the position where the sheet material is last to be attached, and is a portion where air bubbles are likely to occur and where it is difficult to attach the sheet material accurately. With the configuration according to the present invention, the deformed portion of the sheet material is adjacent to or abuts against the deepest portion of the concave curved surface, so that during the attachment process, the sheet material is attached to the curved surface of the workpiece so that it spreads radially from the deepest portion. This reliably prevents the occurrence of air bubbles and other defects in areas where attachment errors are likely to occur in conventional cases, allowing the sheet material to be attached to the curved surface of the workpiece with high precision.

[0023] In the above-described invention, it is preferable that the sheet material comprises a sheet piece having a predetermined shape corresponding to the shape of the workpiece and a long carrier tape for holding the sheet piece.

[0024] (Functions and Effects) According to this configuration, the sheet material includes a sheet piece having a predetermined shape corresponding to the shape of the workpiece and a long carrier tape that holds the sheet piece. In this case, a portion of the sheet piece and the carrier tape is deformed by the deformation member during the contact process, and the deformed portion of the sheet material comes into contact with the curved surface of the workpiece.

[0025] At this time, a large force acts on the sheet piece only in the portion deformed by the deformation member, preventing the sheet piece from being displaced when the sheet material is brought closer to the workpiece. Therefore, the sheet piece of the sheet material can be brought into accurate contact with the target position on the curved surface of the workpiece, further improving the accuracy of the position where the sheet piece is attached to the curved surface of the workpiece.

[0026] In order to achieve the above object, the present invention may have the following configuration. That is, the sheet material joining method includes joining a sheet material to a curved surface of a workpiece in the internal space of a chamber having an upper chamber and a lower chamber, the method comprising: a workpiece holding step of holding the workpiece on a holding table with the curved surface facing upward; an upper and lower space forming step of storing the holding table and sandwiching the sheet material between the upper chamber and the lower chamber, thereby dividing the internal space of the chamber into a lower space in which the workpiece is placed with the curved surface facing upward, and an upper space facing the lower space via the sheet material; a supply step of supplying the sheet material; a deformation step of deforming the sheet material by bringing a deforming member having an abutment surface into contact with the sheet material; a deformation member moving step of moving the deforming member close to the holding table with the deforming member in contact with the sheet material, and bringing the sheet material deformed by the deforming member into contact with or abutting at least a part of the curved surface of the workpiece; and a depressurizing step of evacuating at least the lower space out of the upper and lower spaces. a bonding process in which, with the lower space evacuated and the sheet material in close proximity to or in contact with a portion of the curved surface of the workpiece, the sheet material is bonded to the curved surface of the workpiece by the pressure difference formed between the upper space and the lower space in the chamber separated by the sheet material, wherein the curvature of the contact surface of the deformable member is configured to be greater than the curvature of the curved surface of the workpiece.

[0027] (Operation and Effect) According to this configuration, in a sheet material joining device that joins a sheet material to the curved surface of a workpiece having a curved surface, the sheet material is sandwiched between the upper chamber and the lower chamber while the curved workpiece is held by a holding table, thereby dividing the internal space of the chamber into an upper space and a lower space via the sheet material. At this time, the holding table holding the workpiece is stored in the lower space of the chamber. The sheet material sandwiched between the upper chamber and the lower chamber is deformed by the abutment surface of the deformation member abutting against it. The sheet material deformed by the deformation member approaches or abuts against a portion of the curved surface of the workpiece, and is further joined to the curved surface of the workpiece by the differential pressure generated within the chamber.

[0028] In this case, the curvature of the contact surface of the deforming member is configured to be larger than the curvature of the curved surface of the workpiece. Therefore, when the sheet material deformed by the deforming member is attached to the curved surface of the workpiece, tension caused by the sheet material contacting an unexpected part, such as the edge of the workpiece, can be prevented. This tension can cause wrinkles and air bubbles to form when the sheet material is attached to the curved surface. Therefore, the formation of wrinkles and air bubbles in the sheet material attached to the curved surface of the workpiece can be prevented, allowing the sheet material to be adhered to the curved surface of the workpiece with precision.

[0029] Furthermore, by making the curvature of the contact surface of the deforming member larger than the curvature of the curved surface of the workpiece, the area of ​​the sheet material that contacts the contact surface and deforms is widened, thereby reducing the degree to which the sheet material stretches per unit area of ​​that area. As a result, the variation in the stretch rate of the sheet material is reduced throughout the entire sheet material that is attached to the curved surface of the sheet material workpiece, making it possible to achieve uniform properties throughout the entire workpiece to which the sheet material is attached.

[0030] According to the sheet material joining device and sheet material joining method of the present invention, a sheet material joining device for joining a sheet material to a curved surface of a workpiece having a curved surface includes a chamber and a deformation member. Specifically, the sheet material is sandwiched between an upper chamber and a lower chamber while the curved workpiece is held by a holding table, thereby dividing the interior space of the chamber into an upper space and a lower space via the sheet material. At this time, the holding table holding the workpiece is housed in the lower space of the chamber. The sheet material sandwiched between the upper and lower chambers is deformed by contact with the contact surface of the deformation member. The sheet material deformed by the deformation member approaches or abuts against a portion of the curved surface of the workpiece, and is then joined to the curved surface of the workpiece by the differential pressure generated within the chamber.

[0031] In this case, the curvature of the contact surface of the deforming member is configured to be larger than the curvature of the curved surface of the workpiece. Therefore, when the sheet material deformed by the deforming member is attached to the curved surface of the workpiece, tension caused by the sheet material contacting an unexpected part, such as the edge of the workpiece, can be prevented. This tension can cause wrinkles and air bubbles to form when the sheet material is attached to the curved surface. Therefore, the formation of wrinkles and air bubbles in the sheet material attached to the curved surface of the workpiece can be prevented, allowing the sheet material to be adhered to the curved surface of the workpiece with precision.

[0032] Furthermore, by making the curvature of the contact surface of the deforming member larger than the curvature of the curved surface of the workpiece, the area of ​​the sheet material that contacts the contact surface and deforms is expanded, thereby reducing the degree of stretching of the sheet material per unit area of ​​that area. As a result, the variation in the stretch rate of the sheet material is reduced throughout the entire sheet material that is attached to the curved surface of the workpiece, making it possible to achieve uniform properties throughout the entire workpiece to which the sheet material is attached. In other words, the sheet material can be attached to a curved workpiece with high precision, and the variation in the properties of the sheet material across the entire workpiece can be reduced.

[0033] 1 is a front view showing a basic configuration of a sheet material joining apparatus according to Example 1; FIG. 2 is a perspective view showing a workpiece according to Example 1; (a) is a perspective view showing the shape of a workpiece having a curved surface according to Example 1, (b) is a vertical cross-sectional view showing the shape of a workpiece having a curved surface according to Example 1, and (c) is a perspective view showing another example of a workpiece having a curved surface; FIG. 3 is a cross-sectional view showing the configuration of a sheet material according to Example 1; FIG. 4 is a side view explaining a main part of a sheet material joining apparatus according to Example 1; FIG. 5 is a plan view explaining a main part of a sheet material joining apparatus according to Example 1; FIG. 6 is a side view explaining a main part of a sheet material joining apparatus according to Example 1; FIG. 7 is a diagram explaining a configuration of a chamber according to Example 1; FIG. 8 is a vertical cross-sectional view explaining a relationship between a cross-sectional width of a contact surface of a deformable member according to Example 1 and a cross-sectional width of a curved surface of a workpiece; FIG. 9 is a vertical cross-sectional view explaining a relationship between a curvature of a contact surface of a deformable member according to Example 1 and a curvature of a curved surface of a workpiece; FIG. 10 is a flowchart showing an operation of a sheet material joining apparatus according to an example; (a) is a flowchart of an operation according to Example 1, and (b) is a flowchart of an operation according to Example 2; FIG. 11 is a diagram explaining step S1 according to Example 1; and FIG. 12 is a diagram explaining step S2 according to Example 1. 1 is a diagram for explaining step S2 according to Example 1. FIG. 2 is a diagram for explaining step S3 according to Example 1. FIG. 3 is a diagram for explaining step S4 according to Example 1. FIG. 4 is a diagram for explaining step S5 according to Example 1. FIG. 5 is a diagram for explaining step S5 according to Example 1. FIG. 6 is a diagram for explaining problems of a conventional example. (a) is a diagram for explaining the configuration of a sheet material joining device according to a general conventional example, (b) is a diagram showing a state in which a sheet material comes into contact with a workpiece and tension is generated, (c) is a diagram showing the problem of air bubbles being generated between the sheet material and the workpiece, (d) is a diagram showing a state in which the sheet material comes into contact with a portion other than the target portion, and (e) is a diagram showing the problem of wrinkles being generated in the sheet material. FIG. 7 is a diagram for explaining problems of a conventional example.1A is a diagram illustrating the configuration of a sheet material joining device according to Patent Document 1, (b) is a diagram illustrating a process of joining a sheet material using the sheet material joining device according to Patent Document 1, and (c) is a diagram illustrating the state of the sheet material joined to a workpiece using the sheet material joining device according to Patent Document 1.

[0023] FIG. 1A is a diagram illustrating the elongation rate of the sheet material in Example 1.

[0024] FIG. 1B is a diagram illustrating a first example of a method for calculating the elongation rate of the sheet material in Example 1.

[0025] FIG. 1C is a diagram illustrating the effect of the configuration in Example 1.

[0026] FIG. 1A is a diagram illustrating the configuration of a comparative example in which the shape of the contact surface of a deformable member matches the shape of the curved surface of the workpiece in the comparative example.

[0027] FIG. 1C is a diagram illustrating the position where the deformable member and the workpiece contact when a positional misalignment occurs between the deformable member and the workpiece in Example 1.

[0028] FIG. 1D is a perspective view illustrating the configuration of a sheet material according to Example 2.

[0029] FIG. 1E is a diagram illustrating step S2 according to Example 2. 10 is a diagram illustrating step S3 according to Example 2. FIG. 11 is a diagram illustrating step S3 according to Example 2. FIG. 12 is a diagram illustrating step S4 according to Example 2. FIG. 13 is a diagram illustrating step S5 according to Example 2. FIG. 14 is a diagram illustrating a configuration according to a modified example. FIG. 15 is a diagram illustrating a configuration according to a modified example. FIG. 16 is a diagram illustrating step S3 of a configuration according to a modified example. (a) is a diagram illustrating a state in which an upward differential pressure causes the sheet material to deform so as to move away from a workpiece, and (b) is a diagram illustrating a state in which a protrusion is brought into contact with a target position on the workpiece in a deformed state of the sheet material. FIG. 17 is a diagram illustrating a configuration according to a modified example. FIG. 18 is a diagram illustrating a configuration according to a modified example. FIG. 19 is a diagram illustrating a shape of a workpiece according to a modified example. (a) is a diagram illustrating an example of a configuration in which a central portion of a workpiece has a curved surface and a flat surface, (b) is a diagram illustrating an example of a configuration in which a central portion of a workpiece has a curved surface and a concave portion recessed from the curved surface, and (c) is a diagram illustrating an example of a configuration in which a central portion of a workpiece has a curved surface and a convex portion protruding from the curved surface. FIG. 19 is a diagram illustrating a shape of a workpiece according to a modified example.

[0034] A first embodiment of the present invention will be described below with reference to the drawings. Fig. 1 is a diagram showing the basic configuration of a sheet material joining apparatus 1 according to the first embodiment. Note that in each drawing showing the sheet material joining apparatus 1, illustrations of support means for supporting various components and drive means for driving various components are omitted as appropriate.

[0035] In the sheet material joining apparatus 1 according to this embodiment, a dish-shaped workpiece W, as shown in FIGS. 2( a) and 2(b), is used as the workpiece to which the sheet material PT is to be joined. The peripheral edge portion Wa of the surface W1 of the workpiece W is flat, while the central portion Cp where the circuit is formed has a concave curved surface Wb. The shape of the workpiece W having the curved surface Wb is not limited to a dish shape; other examples include a tile shape as shown in FIG. 2(c). The sheet material joining apparatus 1 aims to join the sheet material PT to at least the central portion Cp of the workpiece W. Examples of the sheet material PT include an adhesive film or an adhesive tape for protecting the circuit.

[0036] As shown in Fig. 3, the sheet material PT used in this embodiment has a long structure in which a non-adhesive substrate Ta and an adhesive material Tb having adhesiveness are laminated together. A separator S is attached to the adhesive material Tb. That is, the separator S is attached to the adhesive surface of the sheet material PT, and the adhesive surface of the sheet material PT is exposed by peeling the separator S from the sheet material PT.

[0037] Examples of materials constituting the substrate Ta include polyolefin, polyethylene, ethylene-vinyl acetate copolymer, polyester, polyimide, polyurethane, vinyl chloride, polyethylene terephthalate, polybutylene terephthalate, polyethylene terenaphthalate, polyvinylidene chloride, polyethylene methacrylic acid copolymer, polypropylene, methacrylic acid terephthalate, polyamide imide, polyurethane elastomer, etc. Note that a combination of two or more of the above-mentioned materials may also be used as the substrate Ta. Furthermore, the substrate Ta may be a single layer, or may be configured with multiple layers laminated together.

[0038] The adhesive material Tb is preferably made of a material that can protect the workpiece W and maintain the sheet material PT adhered to the workpiece W. Examples of materials that can be used to make the adhesive material Tb include acrylic ester copolymer, silicone, olefin, natural rubber, butadiene rubber, and cellulose. It is also preferable to select a material that hardens when exposed to energy rays or thermal energy as the adhesive material Tb. In this case, applying energy rays or thermal energy makes it easy to peel the sheet material PT from the workpiece W. Examples of the separator S include long pieces of paper or plastic.

[0039] <Explanation of Overall Configuration> The sheet material joining device 1 includes a sheet supply section 2, a separator recovery section 3, a sheet joining unit 4, and a sheet recovery section 5. The sheet supply section 2 includes a supply bobbin 6, a tensioning mechanism 7, and a peeling roller 8. The supply bobbin 6 is loaded with a raw roll around which the sheet material PT is wound.

[0040] The supply bobbin 6 is interlocked with an electromagnetic brake 9 to apply an appropriate amount of rotational resistance, thereby preventing excessive unwinding of the sheet material PT from the supply bobbin 6. The tensioning mechanism 7 includes a cylinder 11 that swings a swing arm 10. The swing arm 10 has an idle roller 12 journaled on a support shaft at its fixed end, and a dancer roller 13 at its free end.

[0041] Therefore, the dancer roller 13 at the free end of the swing arm 10, which swings in conjunction with the operation of the cylinder 11, descends and presses down the sheet material PT, applying tension. The sheet material PT unwound from the raw material roll 6 is given tension in the unwinding direction by the guide rollers 14 and the like, and is adjusted to prevent wrinkles from occurring.

[0042] The peeling roller 8 is configured to peel the separator S from the sheet material PT and guide it to the separator recovery unit 3. The separator recovery unit 3 is provided with a recovery bobbin 15 that winds up the separator S peeled from the sheet material PT. The recovery bobbin 15 is controlled to rotate forward and backward by a motor (not shown) or the like.

[0043] The sheet joining unit 4 includes a chamber 17, a sheet joining mechanism 18, a nip roller 19, and a sheet cutting mechanism 21. The chamber 17 is configured by a pair of upper and lower housings, namely an upper housing 20 and a lower housing 22, each having an inner diameter smaller than the width of the sheet material PT. The sheet material joining device 1 according to this embodiment includes one upper housing 20 and two lower housings 22. One of the two lower housings 22 is designated as lower housing 22A, and the other as lower housing 22B.

[0044] As shown in Fig. 4, the lower housings 22A and 22B are provided at both ends of a rotating arm 23. The rotating arm 23 is fixedly connected to a rotation shaft 27 of a rotary drive device 25. That is, for example, when one lower housing 22A moves to the joining area P1 to form the chamber 17 with the upper housing 20, the other lower housing 22B moves to the retreat area P2. As shown in Figs. 1 and 4, the sheet material PT is adjusted to be fed between the upper housing 20 and the lower housing 22 in the joining area P1.

[0045] Additionally, joints 29 are formed on the upper surfaces of the lower housings 22A and 22B, and joint 30 is formed on the lower surface of the upper housing 20. The upper housing 20 and the lower housing 22 are joined via joints 29 and 30 to form the chamber 17. The joining surfaces of joints 29 and 30 have been subjected to a release treatment, such as fluorine treatment.

[0046] As shown in Figures 4 to 6, a holding table 31 is housed in each of the lower housings 22A and 22B. The holding table 31 is configured to be able to rise and fall, and is provided with a workpiece holding portion 33 that holds the workpiece W. A workpiece placing surface 35 is formed in the center of the workpiece holding portion 33. The workpiece placing surface 35 has a shape that conforms to the underside of the workpiece W. In this embodiment, the workpiece placing surface 35 is circular in a plan view and has a concave shape in a cross-sectional view. By placing the workpiece W on the workpiece placing surface 35, the workpiece W can be held more stably.

[0047] It is preferable that the shape of the workpiece placing surface 35 is predetermined so that the height of the peripheral edge Wa of the workpiece W is higher than the height of the upper surface of the holding table 31 when the workpiece W is placed on the workpiece placing surface 35 (see FIG. 7). By making the height of the peripheral edge Wa of the workpiece W higher than the upper surface of the holding table 31, it becomes easier to separate the workpiece W from the holding table 31 after the sheet material PT has been attached.

[0048] The holding table 31 is connected to a rod 37 that passes through the lower housing 22. The other end of the rod 37 is drivingly connected to an actuator 39 that includes a motor or the like. Therefore, the holding table 31 can move up and down inside the lower housing 22.

[0049] The holding table 31 has a plurality of support pins 41 built in. The support pins 41 are configured to be vertically movable, and their tips can be raised higher than the holding surface of the workpiece holding portion 33. A heater 43 is also embedded in the holding table 31.

[0050] As shown in Fig. 6, the upper housing 20 is provided to a drive mechanism 44. The drive mechanism 44 includes a movable base 47 that can be raised and lowered along rails 46 that are vertically arranged on the back of a vertical wall 45, a movable frame 48 that is supported on the movable base 47 so that its height can be adjusted, and an arm 49 that extends forward from the movable frame 48. The upper housing 20 is attached to a support shaft 50 that extends downward from the tip of the arm 49.

[0051] The movable table 47 is configured to be raised and lowered by rotating the screw shaft 51 forward and reverse by a motor 52. Furthermore, the upper housing 20 is configured to be able to retreat from the joining area P1 at an appropriate timing by an operation such as the rotation of the movable table 47 or the extension and retraction of the arm 49.

[0052] 7, the upper housing 20 and the lower housing 22 are connected to a vacuum device 55 via a flow path 53. An electromagnetic valve 56 is provided in the flow path 53 on the vacuum device 55 side. The upper housing 20 and the lower housing 22 are connected to a flow path 59, respectively, which is equipped with electromagnetic valves 57 and 58 for venting to the atmosphere. The upper housing 20 is further connected to a flow path 61, which is equipped with an electromagnetic valve 60 that adjusts the internal pressure by leaking after the pressure has been reduced.

[0053] The opening and closing of the electromagnetic valves 56, 57, 58, and 60 and the operation of the vacuum device 55 are controlled by a control unit 62. The control unit 62 includes a CPU (Central Processing Unit) and is configured to be able to comprehensively control various operations of each of the components provided in the sheet material joining device 1.

[0054] As shown in FIG. 4 and other figures, the sheet joining mechanism 18 includes a deforming member 63 inside the upper housing 20. A cylinder 65 is connected to the top of the deforming member 63, and the operation of the cylinder 65 allows the deforming member 63 to move up and down inside the chamber 17. When the deforming member 63 is lowered with the sheet material PT sandwiched between the upper housing 20 and the lower housing 22, the deforming member 63 deforms the sheet material PT. Preferred examples of materials for the deforming member 63 include elastic bodies, such as rubber, urethane, and elastomers. When the deforming member 63 is an elastic body, it elastically deforms according to the shape of the curved surface Wb of the workpiece W when it contacts the workpiece W via the sheet material PT. This allows the sheet material PT to be adhered appropriately to the workpiece W while preventing damage to the sheet material PT or the workpiece W.

[0055] The nip roller 19 includes a feed roller 67 driven by a motor and a pinch roller 68 that is raised and lowered by a cylinder. The nip roller 19 is configured to be movable left and right along a guide rail 69. The guide rail 69 is mounted on a pair of support frames 71 that are erected on an apparatus base 70 with the chamber 17 sandwiched between them.

[0056] The sheet cutting mechanism 21 is disposed above the joining area P1, and as shown in Figure 1, includes a cutter unit 75 provided at the tip of a support arm 73. The support arm 73 extends radially from the lower tip of the arm, which is cantilevered from a movable base 77. The movable base 77 is configured to be able to move up and down along a frame 79.

[0057] A cutter 81 with its cutting edge facing downward is attached to the cutter unit 75 via a cutter holder. The turning radius of the cutter unit 75 is adjustable via the support arm 73. The sheet cutting mechanism 21 cuts the sheet material PT attached to the workpiece W into a piece of substantially the same shape and size as the peripheral edge Wa of the workpiece W.

[0058] 1, the sheet recovery section 5 is provided with a recovery bobbin 83 that winds up and recovers the unnecessary sheet material PT that has been peeled off after cutting. The recovery bobbin 83 is configured to be driven and rotated forward and backward by a motor (not shown).

[0059] As shown in Figures 7 and 8, the deforming member 63 has a base end 91 and a tip end 93. In Example 1, the base end 91 is a substantially cylindrical member, and the tip end 93 is a member with a spherical lower surface. In other words, the tip end 93 is a member with a shape obtained by cutting out a portion of a sphere. The tip end 93 is connected to the lower part of the base end 91, and an abutment surface 95 is formed on the lower surface of the tip end 93. The abutment surface 95 has a curved surface, and when the deforming member 63 descends, the abutment surface 95 abuts against the sheet material PT. In Example 1, the abutment surface 95 has a curved surface that forms a part of a sphere.

[0060] 8 and 9 show the relationship between the shape of the contact surface 95 of the deforming member 63 and the shape of the curved surface Wb of the workpiece W. As shown in Fig. 8, the width of the contact surface 95 in the vertical cross section is defined as the cross-sectional width a of the contact surface 95, and the width of the curved surface Wb in the vertical cross section of the workpiece W is defined as the cross-sectional width b of the curved surface Wb. That is, in this embodiment, the cross-sectional width a of the contact surface 95 corresponds to the length of the contact surface 95 in the x direction. Furthermore, the cross-sectional width b of the curved surface Wb corresponds to the length of the curved surface Wb in the x direction. In the sheet material joining device 1 according to Example 1, the cross-sectional width a of the contact surface 95 and the cross-sectional width b of the curved surface Wb are configured to satisfy the following condition (1): a ≥ 0.3 × b ... (1)

[0061] That is, the cross-sectional width a of the contact surface 95 is configured to be 0.3 times or more the width b of the curved surface Wb. By configuring the deformation member 63 so that the ratio of the cross-sectional width a to the cross-sectional width b is 0.3 or more, when the sheet material PT is deformed using the deformation member 63, as described below, the ratio of the elongation rate of the sheet material PT in the portion that is deformed by the contact surface 95 to the elongation rate of the sheet material PT in the portion that is not in contact with the contact surface 95 can be reduced. In other words, when the sheet material PT is deformed by the deformation member 63, variation in the elongation rate of the entire sheet material PT can be suppressed.

[0062] In the sheet material joining device 1 according to the first embodiment, the curvature of the contact surface 95 of the deformable member 63 is configured to be larger than the curvature of the curved surface Wb of the workpiece W. The curvatures of the contact surface 95 and the curved surface Wb will now be described with reference to Fig. 9. Fig. 9 shows a vertical cross section of the deformable member 63 and the workpiece W, similar to Fig. 8.

[0063] 9 , a predetermined point on the contact surface 95 of the deformable member 63 is indicated by the symbol NP, and the normal to the contact surface 95 at point NP is indicated by the symbol T1. Furthermore, one end of the contact surface 95 in the width direction (here, the x direction) of the deformable member 63 is indicated by the symbol NL, and the other end of the contact surface 95 is indicated by the symbol NR. The curvature of the curved contact surface 95 corresponds to the amount of change in the slope of the normal T1 while the point NP moves along the arc-shaped contact surface 95 from one end NL to the other end NR.

[0064] 9, a predetermined point on the curved surface Wb of the workpiece W is indicated by the symbol WP, and the normal to the curved surface Wb at point WP is indicated by the symbol T2. One end of the curved surface Wb in the width direction (here, the x-direction) of the curved surface Wb is indicated by the symbol WL, and the other end of the curved surface Wb is indicated by the symbol WR. The curvature of the curved surface Wb of the workpiece W corresponds to the amount of change in the slope of the normal T2 as the point WP moves from one end WL to the other end WR along the arc-shaped curved surface Wb.

[0065] <Outline of Operation> Here, a description will be given of the basic operation of the sheet material joining device 1 according to Example 1. Fig. 10(a) is a flowchart illustrating the process of joining a sheet material PT to a workpiece W using the sheet material joining device 1. Note that in the initial state, it is assumed that the lower housing 22A of the lower housing 22 is disposed in the retraction area P2, and the lower housing 22B is disposed together with the upper housing 20 in the joining area P1.

[0066] Step S1 (Supply of Workpiece) When a joining command is issued, a conveying device (not shown) conveys the workpiece W to the holding table 31. At this time, the workpiece W is conveyed to the holding table 31 inside the lower housing 22 (lower housing 22A in this embodiment) arranged at the retracted position P2. An example of the conveying device is a vacuum suction type robot arm.

[0067] Furthermore, heating by the heater 43 is started at an appropriate timing. By the heater 43 heating the holding table 31, the sheet material PT is heated together with the workpiece W in a subsequent process. As a result, the material constituting the sheet material PT becomes soft, making the sheet material PT more easily deformable.

[0068] When the workpiece W is transported, the holding table 31 rises appropriately, and the support pins 41 built into the holding table 31 protrude from the workpiece holding portion 33 and rise to the receiving position. Then, as shown in Figure 11, the workpiece W is delivered to the tip of the support pins 41, which have been pushed up to a position higher than the upper surface of the lower housing 22A.

[0069] When the workpiece W is transferred, the support pins 41 descend and return to their initial positions, and the workpiece W is placed on the workpiece placement surface 35 of the workpiece holding portion 33. At this time, the height of the holding table 31 is adjusted so that the height of the peripheral portion Wa of the workpiece W held on the holding table 31 via the workpiece placement surface 35 is lower than the height of the upper surface of the lower housing 22A. Note that, in order to hold the workpiece W more stably, the holding table 31 may vacuum-suck the back surface of the workpiece W via the workpiece placement surface 35 using a vacuum device (not shown). By the process of step S1, the workpiece W is held by the holding table 31 with the back surface W2 facing downward and the front surface W1 having the curved surface Wb facing upward.

[0070] At this time, the pinch roller 68 is raised to nip the sheet material PT in cooperation with the feed roller 67, and the dancer roller 13 is swung down to a predetermined height to apply a predetermined tension in the longitudinal direction of the sheet material PT.

[0071] Step S2 (Formation of Chamber) Once the workpiece W is held by the holding table 31, as shown in Fig. 12, the rotary drive device 25 is operated to rotate the swivel arm 23. The rotation of the swivel arm 23 moves the lower housing 22A from the retreat area P2 to the joining area P1. In conjunction with the movement of the lower housing 22A, the lower housing 22B moves from the joining area P1 to the retreat area P2. When the lower housing 22A has moved to the joining area P1, the workpiece W held on the holding table 31 has a predetermined clearance from the sheet material PT.

[0072] After the lower housing 22A is moved to the joining area P1, the upper housing 20 is lowered as shown in Fig. 13. As the upper housing 20 and the lower housing 22A are lowered, the chamber 17 is formed by sandwiching the sheet material PT therebetween.

[0073] The internal space of the formed chamber 17 is divided into two spaces by the sheet material PT: a lower space H1 surrounded by the sheet material PT and the lower housing 22A, and an upper space H2 surrounded by the sheet material PT and the upper housing 20. The workpiece W and the holding table 31 are disposed in the lower space H1, and the upper space H2 faces the lower space H1 with the sheet material PT interposed therebetween.

[0074] Step S3 (Deformation of Sheet Material) After the chamber 17 is formed, the leak electromagnetic valve 60 is closed, and the electromagnetic valves 56, 57, and 58 are opened to operate the vacuum device 53, thereby depressurizing the lower space H1 and the upper space H2. At this time, the openings of the electromagnetic valves 57 and 58 are adjusted so that the lower space H1 and the upper space H2 are depressurized at the same speed. When the air pressure in the lower space H1 and the upper space H2 has been reduced to a predetermined air pressure (for example, a vacuum state), the control unit 62 closes the electromagnetic valves 56-58 and stops the operation of the vacuum device 53.

[0075] After the lower space H1 and the upper space H2 are depressurized to a predetermined air pressure, the control unit 62 activates the sheet pasting mechanism 18. That is, the control unit 62 lowers the deforming member 63. As the deforming member 63 lowers, a tip end 93 of the deforming member 63 comes into contact with and presses against the sheet material PT, as shown in FIG. 14 . This pressure deforms a portion of the sheet material PT according to the shape of the abutment surface 95 provided on the tip end 93, and a protrusion V shaped toward the workpiece W is formed on the sheet material PT. In this embodiment, since the workpiece W is stored in the lower space H1, the protrusion V is shaped to point toward the lower space H1.

[0076] The control unit 62 further lowers the deformation member 63. As the deformation member 63 continues to lower, the sheet material PT is pushed down by the tip 93. As a result, as shown in FIG. 15 , the portion of the sheet material PT that has been deformed as the protrusion V comes into contact with a portion of the curved surface Wb of the workpiece W. In FIG. 15 and other figures, the area of ​​the curved surface Wb that the protrusion V contacts is shown as a contact area M1. In this embodiment, the position of the deformation member 63 is adjusted so that the contact area M1 is an area that includes the deepest part Wc of the curved surface Wb. When the deformation member 63 comes into contact with the curved surface Wb via the protrusion V, the control unit 62 stops the descent of the deformation member 63.

[0077] Step S4 (Attaching the Sheet Material) The process of attaching the sheet material to the workpiece begins after the protrusion V is brought into contact with a portion of the curved surface Wb of the workpiece W. That is, while the protrusion V is in contact with the curved surface Wb, the control unit 62 adjusts the opening of the electromagnetic valve 60 to allow leakage, while gradually increasing the air pressure in the upper space H2 to a preset target value.

[0078] By adjusting the electromagnetic valve 60, the air pressure in the upper space H2 becomes higher than the air pressure in the lower space H1, and a pressure difference F is formed between the two spaces. Then, the sheet material PT is gradually drawn into the lower housing 22A by the pressure difference F between the upper space H2 and the lower space H1.

[0079] At the time when the differential pressure F is formed, the protrusion V, which is part of the sheet material PT, is already in contact with the contact area M1 of the curved surface Wb. Therefore, as shown in FIG. 16 , the sheet material PT is attached to the curved surface Wb of the workpiece W radially from the contact area M1 toward the periphery. Then, as shown in FIG. 17 , the sheet material PT is attached to the entire surface of the curved surface Wb and adheres closely to it. That is, the sheet material PT is attached to the entire surface of the central portion Cp of the surface W1 of the workpiece W. In this embodiment, after the sheet material PT is attached to the central portion Cp, the differential pressure F is further maintained, and the sheet material PT is also attached to the peripheral portion Wa of the surface W1.

[0080] After a predetermined time has elapsed, the control unit 62 opens the electromagnetic valves 57 and 58 to adjust the air pressure in the lower space H1 to be equal to the air pressure in the upper space H2. Once the air pressures in the lower space H1 and the upper space H2 are equal, the control unit 62 adjusts the opening of the electromagnetic valve 60 to return the air pressure in the lower space H1 and the upper space H2 to atmospheric pressure. The upper housing 20 is then raised to open to the atmosphere.

[0081] It should be noted that while the sheet material PT is being attached to the workpiece W in the chamber 17, the process of step S1 can be performed in the lower housing 22B that has moved to the retreat area P2. By providing a plurality of lower housings 22 and alternately performing the process of attaching the sheet material PT to the workpiece W, the efficiency of attaching the sheet material PT to the workpiece W can be improved.

[0082] Step S5 (Cutting of Sheet Material) Once the sheet material PT has been attached to the workpiece W, the cutting process of the sheet material PT begins. That is, the upper housing 20 is retracted from the attachment area P1 to an appropriate position. At this time, the holding table 31 may be raised as appropriate. In this embodiment, the holding table 31 is raised to a height where the surface of the peripheral edge portion Wa of the workpiece W is flush with the upper surface of the lower housing 22A.

[0083] Furthermore, the cutter unit 75 of the sheet cutting mechanism 21 is lowered to a predetermined height. By the vertical movement of the holding table 31 and the sheet cutting mechanism 21, the cutter 81 pierces the sheet material PT at a portion slightly spaced outward from the peripheral edge Wa of the workpiece W, as shown in FIG.

[0084] When the cutter 81 pierces the sheet material PT, the support arm 73 rotates about the vertical axis P. In this embodiment, the vertical axis P is an axis that passes through the center of the holding table 31 and the center of the workpiece W. As the support arm 73 rotates, the cutter 81 rotates along the outer periphery of the peripheral edge Wa of the workpiece W, and the sheet material PT is cut into substantially the same shape and size as the peripheral edge Wa. When cutting of the sheet material PT is completed, the cutter unit 75 rises and returns to the standby position.

[0085] Furthermore, the pinch roller 68 provided on the nip roller 19 is lowered to release the nip of the sheet material PT. Then, as shown in Fig. 19, the nip roller 19 is moved along the guide rail 69 toward the tape supply unit 2, thereby separating the sheet material PTw, which is the portion of the sheet material PT that has been cut out along the outline of the peripheral edge Wa, from the sheet material PTa, which is the portion other than the sheet material PTw.

[0086] Step S6 (Recovery of Workpiece) Once cutting and separation of the sheet material PT is complete, the rotary drive device 25 is operated to rotate the swivel arm 23. The rotation of the swivel arm 23 moves the lower housing 22A from the joining area P1 to the retreat area P2. In conjunction with the movement of the lower housing 22A, the lower housing 22B moves to the joining area P1. The workpiece W with the sheet material PTw joined to its curved surface Wb is then carried out by a transport mechanism (not shown) and collected in a workpiece storage unit (not shown).

[0087] The sheet material PTa separated from the sheet material PTw is wound and collected by the collection bobbin 83 of the sheet collection section 5. As the sheet material PTa is collected, a predetermined amount of the sheet material PT is fed from the sheet supply section 2.

[0088] This completes one cycle of operations, and thereafter, the operations from step S1 to step S6 are repeated in sequence.

[0089] <Effects of the Configuration of Example 1> According to the device of Example 1, the sheet material PT can be attached with high precision to the workpiece W having the curved surface Wb. Here, the effects of the configuration of Example 1 will be described in comparison with a conventional configuration.

[0090] Conventional bonding devices such as those disclosed in Patent Document 1 and Patent Document 2 are designed for a process of bonding a sheet material PT to a flat workpiece. Therefore, it has been newly discovered that when the workpiece has a curved surface, it is difficult to bond the sheet material PT to the workpiece with high precision using conventional bonding devices.

[0091] The following are thought to be the reasons why it is difficult to attach the sheet material to a workpiece with high accuracy. That is, in a typical conventional configuration in which a differential pressure is used to attach the sheet material to a workpiece, as shown in Figure 20(a), a differential pressure F is generated inside the chamber Ty while the sheet material PT is in a flat state, and the sheet material PT is attached to the workpiece W using this differential pressure F. In such a typical conventional configuration, the entire sheet material PT inside the chamber Ty is uniformly deformed by the differential pressure F. Therefore, the portions of the workpiece W that are closer to the sheet material PT will come into contact with the sheet material PT first, compared to the portions of the workpiece W that are farther away from the sheet material PT.

[0092] 20(b), when a workpiece W having a curved surface Wb is used as the workpiece, the sheet material PT comes into contact with the flat peripheral edge Wa of the workpiece W, which is located higher in the z direction, before the concave curved surface Wb of the workpiece W, which is located lower in the z direction. When the sheet material PT comes into contact with the peripheral edge Wa in this way, tension Tx is generated in the sheet material PT.

[0093] In this case, the central portion of the sheet material PT, which is in contact with the peripheral edge Wa, further deforms to conform to the curved surface Wb. However, tension Tx is generated in the sheet material PT, and this tension Tx gradually increases as the sheet material PT deforms to conform to the curved surface Wb. Therefore, the sheet material PT cannot deform any further, and a part of the sheet material PT cannot conform to the curved surface Wb.

[0094] When this occurs, the sheet material PT cannot adhere to the curved surface Wb in the portion where it cannot deform, and as a result, air bubbles Vo are generated between the sheet material PT and the curved surface Wb of the workpiece W, as shown in Figure 20(c). In particular, the deepest portion Wc, which is the deepest part of the curved surface Wb, is the last part that the sheet material PT, which is deformed by the pressure difference, comes into contact with, and therefore air bubbles Vo are generated with high frequency. As a result, the adhesion accuracy of the sheet material PT decreases in the particularly deep portion of the curved surface Wb.

[0095] The tension Tx generated by the sheet material PT first contacting the peripheral edge Wa is thought to cause another problem. Specifically, if the sheet material PT deforms to conform to the curved surface Wb while tension Tx is being generated, the sheet material PT will deform unevenly. As a result, as shown in Figure 20(d), a portion of the sheet material PT will first adhere to an unexpected area Wbx of the curved surface Wb. When this occurs, the sheet material PT will not be able to adhere tightly to the curved surface Wb, and the portion of the sheet material PT that contacts the area Wbx will develop a wrinkle Sw, as shown in Figure 20(e).

[0096] Furthermore, even if the sheet material PT is attached to the curved surface Wb while tension Tx is being generated, a strong tensile stress is accumulated in the sheet material PT due to the tension Tx. As a result, the sheet material PT may peel off from the curved surface Wb over time due to the tensile stress, which may result in the formation of air bubbles Vo and wrinkles Sw.

[0097] In order to prevent the sheet material PT from coming into contact with the peripheral edge Wa before the curved surface Wb when the sheet material PT is attached to the curved surface Wb of the workpiece W, the configuration of Patent Document 1 has a thin rod-shaped protruding member 101 disposed inside the chamber Ty as shown in Fig. 21(a). Then, as shown in Fig. 21(b), the protruding member 101 is lowered and the central portion Q1 of the sheet material PT is pressed by a pressing member K to attach it to the workpiece W, and then a pressure difference is generated to cause the sheet material PT to be in close contact with the entire surface of the workpiece W so as to spread radially from the central portion.

[0098] However, it was found that the configuration of Patent Document 1 newly generates the following problem. As shown in FIG. 21(b), the protruding member 101 is a thin rod-shaped member, and therefore contacts and presses against a very narrow region Q1 of the sheet material PT. Therefore, a very large pressing force acts on the narrow region Q1, and the region Q1 of the sheet material PT is greatly stretched by this pressing force. In other words, the stretching rate of the sheet material PT in the region Q1 becomes very high. Furthermore, when the sheet material PT is stretched, it becomes thinner. In other words, the thickness of the region Q1 of the sheet material PT becomes thinner.

[0099] On the other hand, in the region Q2 of the sheet material PT where the protruding member 101 does not contact, the pressing force exerted by the protruding member 101 is very weak, so the stretching rate of the sheet material PT in the region Q2 is low. Also, the sheet material PT in the region Q2 is thicker than the sheet material PT in the region Q1. That is, in the configuration of Patent Document 1, the protruding member 101 causes variations in the stretching rate and thickness depending on the position of the sheet material PT.

[0100] When the sheet material PT is attached to the curved surface Wb of the workpiece W in a state where such variations in the elongation rate and thickness have occurred, the sheet material PT attached to the curved surface Wb will be in the state shown in Figure 21(c). That is, a region Q1 of the sheet material PT is attached to the center of the curved surface Wb, and a region Q2 of the sheet material PT is attached to the peripheral portion of the curved surface Wb. Therefore, the thickness of the sheet material PT attached to the center of the curved surface Wb is relatively thin, and the thickness of the sheet material PT attached to the peripheral portion of the curved surface Wb is relatively thick.

[0101] The characteristics of the sheet material PT, such as light transmittance, vary greatly depending on the thickness of the sheet material PT. As a result, the characteristics of the sheet material PT attached to the center of the curved surface Wb will be significantly different from the characteristics of the sheet material PT attached to the peripheral edge of the curved surface Wb. Therefore, it is considered difficult for the conventional sheet material attachment device disclosed in Patent Document 1 to exhibit the characteristics of the sheet material PT uniformly over the entire curved surface Wb.

[0102] On the other hand, in the sheet material joining device 1 according to Example 1, the sheet material PT is deformed using the contact surface 95 of the deformation member 63, and the deformed portion of the sheet material PT is brought into contact with the curved surface Wb of the workpiece W. Then, with the deformed portion of the sheet material PT in contact with the curved surface Wb of the workpiece W, a differential pressure F is generated to join the sheet material PT to the entire curved surface Wb. The contact surface 95 of the deformation member 63 is configured so that its curvature is greater than the curvature of the curved surface Wb of the workpiece W. The configuration of the contact surface 95 with respect to the curved surface Wb of the workpiece W is determined so that the cross-sectional width a of the contact surface 95 and the cross-sectional width b of the curved surface Wb satisfy the condition a ≥ 0.3 × b.

[0103] By configuring the cross-sectional width or curvature of the contact surface 95 of the deforming member 63 to satisfy this condition, the area of ​​the sheet material PT that the contact surface 95 contacts can be increased when the deforming member 63 is brought into contact with the sheet material PT. As a result, the pressing force acting per unit area of ​​the sheet material PT during the process in which the deforming member 63 deforms the sheet material PT can be reduced, thereby preventing an excessive increase in the elongation rate of the sheet material PT in the area where the contact surface 95 contacts. This reduces the difference in elongation rate between the area of ​​the sheet material PT where the contact surface 95 contacts and the area where the contact surface 95 does not contact, thereby reducing the variation in the elongation rate throughout the sheet material PT attached to the curved surface Wb of the workpiece W. In other words, this reduces the variation in the thickness of the sheet material PT on the curved surface Wb, allowing the sheet material to exhibit its properties more uniformly throughout the entire sheet material PT attached to the curved surface Wb.

[0104] In this embodiment, the extension rate of the sheet material PT is calculated by the following method, for example. Figure 22(a) shows a first example of calculating the extension rate. The left diagram of Figure 22(a) shows the deformable member 63 and the sheet material PT in a state where the contact surface 95 of the deformable member 63 is not in contact with the sheet material PT. In this state, the length of the portion J of the sheet material PT facing the contact surface 95 is defined as F1. In the left diagram of Figure 22(a), the contact surface 95 is not in contact with the sheet material PT, so the length F1 is equal to the cross-sectional width a of the contact surface 95.

[0105] Next, the right diagram of Figure 22(a) shows the deforming member 63 and the sheet material PT in a state where the contact surface 95 of the deforming member 63 is in contact with the sheet material PT. In this state, the length of the portion of the sheet material PT facing the contact surface 95 (the portion where the contact surface 95 is in contact) is defined as F2. In the right diagram of Figure 22(a), the sheet material PT is deformed along the contact surface 95, so the length F2 is the length along the surface of the contact surface 95. In this first example, the extension rate Ex of the sheet material PT caused by the contact of the deforming member 63 is calculated by the following formula (3) using the length F1 of the sheet material PT before deformation and the length F2 of the sheet material PT after deformation: Ex = (F2 - F1) / F1 (3)

[0106] In the above-mentioned formula (3), F1 corresponds to the initial length of the facing portion J, and (F2-F1) corresponds to the length of the facing portion J stretched by the deformation member 63. Therefore, the stretch rate Ex of the sheet material PT can be calculated by formula (3).

[0107] Next, FIG. 22(b) shows a second example of calculating the extension ratio. The left diagram of FIG. 22(b) shows a plan view of the sheet material PT before the deforming member 63 is brought into contact with the sheet material PT. The right diagram of FIG. 22(b) shows a plan view of the sheet material PT after the deforming member 63 is brought into contact with the sheet material PT. That is, by bringing the contact surface 95 of the deforming member 63 into contact with the sheet material PT, the length of the sheet material PT in the x direction changes from X1 to X2, and the length of the sheet material PT in the y direction changes from Y1 to Y2. In this second example, the extension ratio Ex of the sheet material PT caused by bringing the deforming member 63 into contact with the sheet material PT can also be calculated using the lengths X1, X2, Y1, and Y2 in the following formula (4). The term (X1·Y1) corresponds to the product of the lengths X1 and Y1.

[0108] Furthermore, in the configuration according to Example 1, the curvature of the contact surface 95 of the deformation member 63 is configured to be greater than the curvature of the curved surface Wb of the workpiece W. Therefore, by bringing the sheet material PT deformed by the contact surface 95 and the deformation member 63 close to the curved surface Wb of the workpiece W, it becomes easy to first bring the sheet material PT into contact with the deepest part Wc, which is the deepest part of the curved surface Wb. Therefore, in the process of bonding the sheet material PT to the curved surface Wb by differential pressure, the sheet material PT is bonded radially outward from the deepest part Wc. This reliably prevents air bubbles from being trapped in the deepest part Wc, which was previously thought to be a part where air bubbles were particularly likely to form, thereby further improving the adhesion of the sheet material PT to the curved surface Wb.

[0109] Furthermore, it has been found that by making the curvature of the contact surface 95 larger than the curvature of the curved surface Wb of the workpiece W, a new effect can be obtained in which the sheet material PT can be attached with high precision even if a misalignment occurs between the position of the deformable member 63 and the position of the workpiece W. This effect will be explained using the diagrams in FIG.

[0110] 23A shows a configuration in which the shape of the abutment surface 95 matches the shape of the curved surface Wb of the workpiece W. In this case, the curvature and cross-sectional width of the abutment surface 95 are equal to the curvature and cross-sectional width of the curved surface Wb of the workpiece W. In such a configuration in which the shape of the abutment surface 95 matches the shape of the curved surface Wb of the workpiece W, if the positions of the deforming member 63 and the workpiece W in the x and y directions match with high precision, the sheet material PT can be attached to the entire curved surface Wb with high precision. In other words, if the center line Kn of the abutment surface 95 and the center line Kw of the curved surface Wb match with high precision, the abutment surface 95 comes into contact with the entire curved surface Wb of the workpiece W by lowering the deforming member 63, so that the sheet material PT can be attached to the entire curved surface Wb with high precision.

[0111] However, in a configuration in which the shape of the contact surface 95 matches the shape of the curved surface Wb of the workpiece W, the accuracy of attaching the sheet material PT is significantly reduced due to a slight misalignment between the center line Kn of the contact surface 95 and the center line Kw of the curved surface Wb. Figure 23(a) shows a state in which the shape of the contact surface 95 matches the shape of the curved surface Wb of the workpiece W, in which the center line Kn of the contact surface 95 and the center line Kw of the curved surface Wb are slightly misaligned in the x direction.

[0112] When the deforming member 63 is lowered in the state shown in Figure 23(a), the positional relationship between the deforming member 63 and the workpiece W becomes as shown in Figure 23(b). If the center line Kn of the contact surface 95 is misaligned with the center line Kw of the curved surface Wb, the contact surface 95 will be unable to contact the curved surface Wb, even if the distance of misalignment (amount of misalignment) is small. In other words, the contact surface 95 will come into contact with the flat peripheral edge Wa or the boundary between the peripheral edge Wa and the curved surface Wb (for example, one end WL or the other end WR) via the sheet material PT.

[0113] 23(b), the contact surface 95 does not fit into the curved surface Wb, and therefore the sheet material PT cannot be attached to the curved surface Wb with high precision even if the deformation member 63 is further lowered. Furthermore, even if a differential pressure F is generated in the state shown in FIG. 23(b), the sheet material PT is attached to the peripheral edge portion Wa of the workpiece W before being attached to the curved surface Wb, which frequently results in air bubbles Vo being trapped between the sheet material PT and the workpiece W or wrinkles Wbx being formed in the sheet material PT attached to the workpiece W (see FIGS. 20(b) to 20(d)).

[0114] Therefore, in a configuration in which the shape of the abutment surface 95 matches the shape of the curved surface Wb of the workpiece W, the position of the deformation member 63 in the horizontal direction (x direction and y direction) must be matched with the position of the workpiece W with extremely high precision, and even a slight positional misalignment will significantly reduce the accuracy of the attachment of the sheet material PT.

[0115] On the other hand, if the curvature of the contact surface 95 of the deformable member 63 is greater than the curvature of the curved surface Wb of the workpiece W, the sheet material PT can be attached with high precision even if there is a misalignment between the deformable member 63 and the workpiece W. Figure 23(c) shows a state in which the deformable member 63 is lowered and brought into contact with the workpiece W when the positions of the center line Kn of the contact surface 95 and the center line Kw of the curved surface Wb are misaligned in the x direction.

[0116] When the curvature of the contact surface 95 is greater than the curvature of the curved surface Wb, the distance between the center of the contact surface 95 and the curved surface Wb of the workpiece W is sure to be greater than the distance between the peripheral edge of the contact surface 95 and the curved surface Wb of the workpiece W. Therefore, even if the positions of the center line Kn of the contact surface 95 and the center line Kw of the curved surface Wb are misaligned in the horizontal direction, the curved portion of the contact surface 95 will surely come into contact with the curved surface Wb of the workpiece W, as shown in Figure 23(c).

[0117] Furthermore, when misalignment occurs, the position of the region M2 where the contact surface 95 and the curved surface Wb come into contact is close to the position of the contact region M1 when no misalignment occurs (for example, the position of the deepest part Wc). Therefore, when a differential pressure F is generated while the contact surface 95 is in contact with the contact region M2 on the curved surface Wb via the sheet material PT, the sheet material PT is attached to the entire curved surface Wb so as to spread radially from the contact region M2, which is close to the contact region M1 (the deepest part Wc), as a starting point.

[0118] As a result, it is possible to reliably prevent the inclusion of air bubbles Vo or the occurrence of wrinkles Wbx. That is, unlike a configuration in which the shape of the contact surface 95 matches the shape of the curved surface Wb of the workpiece W, a configuration in which the curvature of the contact surface 95 is greater than the curvature of the curved surface Wb greatly increases the tolerance for horizontal positional deviation between the deformable member 63 and the workpiece W. In other words, in a configuration in which the curvature of the contact surface 95 is greater than the curvature of the curved surface Wb, even if the positions of the center line Kn of the contact surface 95 and the center line Kw of the curved surface Wb are misaligned in the horizontal direction, the sheet material PT can be attached to the curved surface Wb of the workpiece W with high precision.

[0119] Next, a second embodiment of the present invention will be described. In the first embodiment, a configuration in which a long sheet material PT is attached to a workpiece W having a curved surface Wb is described as an example. In the second embodiment, a configuration in which a piece of sheet material PT having a predetermined shape corresponding to the shape of the workpiece W is attached to a predetermined area including the curved surface Wb is described as an example. That is, in the second embodiment, a configuration in which pre-cut adhesive tape is attached to a workpiece is described as an example. Note that the same components as those in the sheet material attaching device 1 according to the first embodiment are designated by the same reference numerals, and different components will be described in detail.

[0120] As shown in Figure 24, the sheet material PT according to Example 2 is pre-cut into a predetermined shape, and each sheet material PT is held by a long carrier tape CT. That is, in the sheet material joining device 1A according to Example 2, pieces of the sheet material PT having a predetermined shape are arranged at predetermined distances on the carrier tape CT, and the carrier tape CT is fed and supplied from the sheet supply unit 2 together with the sheet material PT. The sheet joining unit 4 joins the pieces of the sheet material PT to the circuit formation surface of the workpiece W having a curved surface Wb. The sheet recovery unit 5 winds up and recovers the carrier tape CT peeled from the sheet material PT.

[0121] In this embodiment, the shape of the sheet material PT is assumed to be circular. In addition, since the sheet material PT is already shaped to match the outer shape of the workpiece W, the sheet cutting mechanism 21 can be omitted from the sheet material joining device 1A.

[0122] The operation of the sheet material joining apparatus 1A according to the second embodiment will be described while illustrating the differences from the first embodiment. The flowchart of the operation of the sheet material joining apparatus 1A is as shown in Fig. 10(b). The outline of the sheet material joining process according to the second embodiment is the same as the process according to the first embodiment, and therefore the detailed description will be omitted as appropriate.

[0123] Step S1 (Supply of Workpiece) In step S1, the workpiece W having the curved surface Wb is transported to the lower housing 22A arranged in the retreat area P2. The workpiece W is then placed on the holding table 31 housed in the lower housing 22A, and the workpiece W is held via the workpiece placing surface 35 of the holding table 31. The workpiece W is held with the surface W1 having the curved surface Wb facing upward.

[0124] Step S2 (Formation of Chamber) Next, in step S2, the lower housing 22A is moved to the joining area P1. At this time, the position of the sheet material PT being fed out is adjusted in advance so that it is above the curved surface Wb of the workpiece W. After the lower housing 22A has been moved, the upper housing 20 is lowered. As shown in Figure 25, the upper housing 20 and the lower housing 22A are joined together with the carrier tape CT sandwiched therebetween to form the chamber 17.

[0125] The formed internal space of the chamber 17 is divided into two spaces by the carrier tape CT: a lower space H1 surrounded by the carrier tape CT and the lower housing 22A, and an upper space H2 surrounded by the carrier tape CT and the upper housing 20.

[0126] Step S3 (Deformation of Sheet Material) After the chamber 17 is formed, the vacuum device 53 is operated to depressurize the lower space H1 and the upper space H2 at the same speed. When the air pressure in the lower space H1 and the upper space H2 is reduced to a predetermined pressure, the sheet attachment mechanism 18 is started to operate and the deforming member 63 is lowered. By lowering the deforming member 63, as shown in FIG. 26 , the contact surface 95 provided on the tip 93 of the deforming member 63 comes into contact with the sheet material PT via the carrier tape CT and presses the sheet material PT. This pressure deforms a portion of the sheet material PT according to the shape of the contact surface 95, forming a protrusion V.

[0127] After the sheet material PT has been deformed by the contact surface 95, the control unit 62 further lowers the deformation member 63. As the deformation member 63 continues to lower, the protrusion V comes into contact with a portion of the curved surface Wb of the workpiece W, as shown in FIG. 27. As in Example 1, it is preferable to adjust the position of the deformation member 63 so that the contact area M1 of the curved surface Wb with which the protrusion V comes into contact is an area that includes the deepest part Wc of the curved surface Wb. When the deformation member 63 comes into contact with the curved surface Wb via the protrusion V, the control unit 62 stops the lowering of the deformation member 63.

[0128] Step S4 (Attaching the Sheet Material) After the protrusion V is brought into contact with a portion of the curved surface Wb of the workpiece W, a pressure difference is created between the upper space H2 and the lower space H1 while the protrusion V is in contact with the curved surface Wb. The pressure difference between the upper space H2 and the lower space H1 gradually draws the sheet material PT into the lower housing 22A. The sheet material PT is then attached to the curved surface Wb of the workpiece W, spreading radially from the contact area M1 toward the periphery. As a result, the sheet material PT is attached to the entire surface of the curved surface Wb, as shown in FIG. 28 .

[0129] After a predetermined time has elapsed, the control unit 62 raises the deformable member 63 to return it to its initial position, and adjusts the air pressure in the lower space H1 to be equal to the air pressure in the upper space H2. Thereafter, the air pressure in the lower space H1 and the upper space H2 is returned to atmospheric pressure, and the upper housing 20 is raised to be open to the atmosphere.

[0130] Step S5 (Peeling of Carrier Tape) Since the sheet material PT in Example 2 is already in pieces shaped according to the outer shape of the workpiece W, the step of cutting the sheet material PT can be omitted. Therefore, in Example 2, after the sheet material PT is attached to the workpiece W, a step of peeling the carrier tape CT from the sheet material PT is performed. That is, the upper housing 20 is retracted from the attachment area P1 to an appropriate position. At this time in Example 2, the holding table 31 is raised as in Example 1.

[0131] Next, the pinch roller 68 provided on the nip roller 19 is lowered to release the nip of the sheet material PT. Then, as shown in Figure 29, the nip roller 19 is moved along the guide rail 69 toward the tape supply unit 2, whereby the carrier tape CT is wound up and peeled off from the sheet material PT attached to the workpiece W.

[0132] Step S6 (Recovery of Workpiece) After the carrier tape CT has been peeled off, the pivot arm 23 is pivoted to move the lower housing 22A from the joining area P1 to the retreat area P2. The workpiece W with the sheet material PT joined to the curved surface Wb is then carried out by a transport mechanism (not shown) and collected in a workpiece storage unit (not shown). The carrier tape CT separated from the sheet material PT is wound and collected by the collection bobbin 83 of the sheet collection unit 5.

[0133] This completes one cycle of operations, and thereafter, the operations from step S1 to step S6 are repeated in sequence.

[0134] <Effects of the Configuration of Example 2> According to the device of Example 2, when a precut adhesive tape-like sheet material PT is attached to a workpiece W having a curved surface Wb, the sheet material PT can be attached to the curved surface Wb with high precision. That is, as in Example 1, a portion of the sheet material PT is deformed to form a protrusion V, and the protrusion V is first brought into contact with a portion of the curved surface Wb. After the protrusion V has contacted the curved surface Wb, the sheet material PT is attached to the entire curved surface Wb by the pressure difference between the lower space H1 and the upper space H2 inside the chamber 17.

[0135] Therefore, even in the configuration of Example 2, it is possible to avoid the occurrence of tension Tx caused by the sheet material PT first contacting the peripheral edge Wa. Therefore, even when attaching the sheet material PT to a workpiece W having a curved surface Wb, it is possible to avoid situations such as wrinkles occurring in the sheet material PT or air bubbles occurring between the sheet material PT and the curved surface Wb. Therefore, it is possible to attach the sheet material PT with high precision so that it is in close contact with the entire surface of the curved surface Wb.

[0136] In the second embodiment, similarly to the first embodiment, the contact surface 95 of the deformable member 63 is configured so that its curvature is greater than the curvature of the curved surface Wb of the workpiece W. The configuration of the contact surface 95 with respect to the curved surface Wb of the workpiece W is determined so that the cross-sectional width a of the contact surface 95 and the cross-sectional width b of the curved surface Wb satisfy the condition a ≥ 0.3 × b.

[0137] By configuring the cross-sectional width and curvature of the contact surface 95 of the deforming member 63 to satisfy these conditions, the area of ​​the sheet material PT that the contact surface 95 contacts can be increased when the deforming member 63 is brought into contact with the sheet material PT. As a result, the pressing force acting per unit area of ​​the sheet material PT during the process in which the deforming member 63 deforms the sheet material PT can be reduced, thereby preventing an excessive increase in the elongation rate of the sheet material PT in the area where the contact surface 95 contacts. This reduces the difference in elongation rate between the area of ​​the sheet material PT where the contact surface 95 contacts and the area where the contact surface 95 does not contact, thereby reducing the variation in the elongation rate throughout the sheet material PT attached to the curved surface Wb of the workpiece W. In other words, this reduces the variation in the thickness of the sheet material PT on the curved surface Wb, allowing the sheet material to exhibit its properties more uniformly throughout the entire sheet material PT attached to the curved surface Wb.

[0138] Furthermore, by making the curvature of the contact surface 95 larger than the curvature of the curved surface Wb of the workpiece W, the sheet material PT can be attached with high precision even if a misalignment occurs between the position of the deformable member 63 and the position of the workpiece W. In other words, unlike a configuration in which the shape of the contact surface 95 matches the shape of the curved surface Wb of the workpiece W, a configuration in which the curvature of the contact surface 95 is larger than the curvature of the curved surface Wb can greatly increase the tolerance for misalignment in the horizontal direction between the deformable member 63 and the workpiece W.

[0139] Furthermore, in the configuration according to Example 2, the deformation member 63 presses against a portion of the precut sheet material PT, deforming that portion into a shape that protrudes toward the workpiece W, forming a protrusion V. With the protrusion V formed, horizontal displacement of the sheet material PT is suppressed. Therefore, in step S3, the protrusion V of the sheet material PT can be brought into contact with a desired position (contact area M1) on the curved surface Wb of the workpiece W with high precision. As a result, the accuracy of the position at which the sheet material PT is attached in the attachment step according to step S4 can be significantly improved compared to the conventional method. Therefore, in the method of attaching the precut sheet material PT to the workpiece W using differential pressure, the sheet material PT can be attached in a more accurate position.

[0140] It should be noted that the embodiments disclosed herein are illustrative in all respects and are not limiting. The scope of the present invention is defined by the claims rather than the above description of the embodiments, and includes all modifications (variations) within the meaning and scope of the claims. For example, the present invention can be modified as follows:

[0141] (1) In each embodiment, the sheet material PT has been described as an example of the sheet material to be attached to the workpiece W, but the sheet material is not limited to this. In addition to adhesive tape for protecting the circuit surface, adhesive tape used for other purposes, such as supporting adhesive tape (dicing tape), may also be used. In the present invention, a sheet, tape, film, or the like having an adhesive material with adhesive force or an adhesive material with adhesive force can be used as the sheet material.

[0142] The structure of the sheet material is not limited to the structure shown in Figure 3 in which the adhesive material Tb is laminated on one side of the base material Ta, but may also be a laminate structure of an adhesive material and a base material. Suitable examples include a single-layer structure of adhesive or adhesive material without a base material, as well as a structure in which adhesive or adhesive material is provided on both sides of the base material Ta. Furthermore, a sheet material consisting of only the base material Ta may be used as long as the sheet material can be in close contact with the workpiece W.

[0143] In this embodiment, the separator S is attached to the sheet-shaped adhesive material T, but the separator S may be omitted depending on the structure of the sheet material joining device 1 or the sheet material.

[0144] (2) In each embodiment, a workpiece W having a concave curved surface Wb is exemplified as the workpiece to which the sheet material is attached, but the shape and material of the workpiece are not limited to this. The configuration according to this embodiment can be applied to materials used for various semiconductor components, such as substrates, panels, and wafers, as well as ceramics, such as porcelain, resin, metal, glass, wood, stone, paper, or a mixture of the above materials. Furthermore, the shape of the workpiece may be circular, rectangular, polygonal, or approximately circular, etc.

[0145] (3) In each of the examples, the workpiece W has a concave curved surface Wb, but the curved surface is not limited to a concave shape and may be, for example, a convex shape. When attaching a sheet material PT to a convex curved surface Wd provided on the workpiece W, as shown in Figure 30, a part of the sheet material PT is deformed to form a protrusion V, and the protrusion V is brought into contact with a part of the convex curved surface Wd before the attaching process using differential pressure begins.

[0146] In this case, it is preferable that the contact area M1 with which the protrusion V comes into contact is an area including the apex We, which is the highest part of the convex curved surface Wd. By starting the bonding process using differential pressure with the protrusion V in contact with the apex We, it is possible to more reliably prevent air bubbles from being trapped between the sheet material PT and the workpiece W and wrinkles from occurring in the sheet material PT.

[0147] (4) In each embodiment, the differential pressure joining process, i.e., the process related to step S4, is started with the deforming member 63 in contact with the curved surface Wb via the protrusion V. However, this is not limited to this. That is, if the protrusion V of the sheet material PT is stably attached to the curved surface Wb, the differential pressure joining process may be started after the deforming member 63 is raised, as shown in FIG. 31 . Even with the configuration related to this modified example, the differential pressure joining process is started with the sheet material PT in contact with a portion of the curved surface Wb. Therefore, the sheet material PT can be joined to the curved surface Wb of the workpiece W radially from the contact area M1 without generating tension Tx in the sheet material PT. Therefore, the sheet material PT can be precisely adhered to the entire curved surface Wb.

[0148] (5) In each embodiment, the shape of the deformable member 63 may be changed as appropriate. Examples of the shape of the base end 91 of the deformable member 63 include a cylindrical shape, a cone shape, a pyramid shape, a rectangular parallelepiped shape, a truncated cone shape, and a truncated pyramid shape. Examples of the shape of the tip end 93 of the deformable member 63 include a shape obtained by cutting out a part of a sphere (true sphere) and a shape obtained by cutting out a part of an ellipsoid.

[0149] (6) In each embodiment, after the deforming member 63 contacts the curved surface Wb via the protruding portion V, control to generate a differential pressure F between the lower space H1 and the upper space H2 is initiated, but the timing of contacting the protruding portion V with the curved surface Wb is not limited to this. In other words, the differential pressure F may be generated in a state where the protruding portion V of the sheet material PT formed by the contact surface 95 of the deforming member 63 is in close proximity to the curved surface Wb of the workpiece W (in a non-contact state).

[0150] In this case, after the lower space H1 and the upper space H2 are depressurized to a vacuum state, the abutment surface 95 of the deforming member 63 is brought into contact with the sheet material PT to deform it and form the protrusion V. The deforming member 63 is then lowered and moved toward the curved surface Wb of the workpiece W. At this time, when the tip portion 93 has moved to a position where a small gap is formed between the protrusion V and the curved surface Wb, the control unit 62 stops the lowering of the deforming member 63. Then, with the protrusion V approaching the curved surface Wb, the control unit 62 starts control to generate a differential pressure F between the lower space H1 and the upper space H2.

[0151] The generation of the pressure difference F causes the sheet material PT constituting the protrusion V to be attached to the contact area M1 by the pressure difference F. Then, starting from the contact area M1, the sheet material PT is attached to the entire curved surface Wb in a radially expanding manner. By generating the pressure difference F and attaching the sheet material PT to the curved surface Wb of the workpiece W while the protrusion V is in close proximity to the curved surface Wb, it is possible to more reliably prevent air bubbles Vo from being trapped between the workpiece W and the sheet material PT.

[0152] (7) In each embodiment, control may be performed to make the air pressure in the lower space H1 higher than the air pressure in the upper space H2 before lowering the deformable member 63 in step S3 to form the protrusion V. That is, after starting step S3 and reducing the air pressure in the lower space H1 and the upper space H2 to a predetermined air pressure at a uniform rate, the control unit 62 adjusts the opening degree of each of the electromagnetic valves so that the air pressure in the lower space H1 becomes higher than the air pressure in the upper space H2.

[0153] 32(a), the air pressure in the lower space H1 becomes higher than the air pressure in the upper space H2, generating a pressure difference Fb between the two spaces. The pressure difference Fb then deforms the sheet material PT so that it moves away from the workpiece W. After the sheet material PT has been deformed by the pressure difference Fb, the deformation member 63 is lowered to form the protrusion V.

[0154] In this modified example, the protrusion V is formed while the differential pressure Fb is being generated, so that in the process of forming the protrusion V and bringing the protrusion V into contact with the curved surface Wb, the sheet material PT in the portions other than the protrusion V is deformed so as to move away from the workpiece W (FIG. 32(b)). Therefore, in the process of bringing the protrusion V into contact with the curved surface Wb, it is possible to avoid a situation in which the sheet material PT in the portions other than the protrusion V comes into contact with the workpiece W first.

[0155] That is, when the protrusion V is brought into contact with the contact area M1 of the curved surface Wb, it is possible to prevent the sheet material PT other than the protrusion V from coming into contact with unintended portions of the curved surface Wb or portions of the peripheral edge Wa. As a result, it is possible to prevent wrinkles or air bubbles from occurring when the sheet material PT is attached to the curved surface Wb.

[0156] After bringing the protrusions V into contact with the curved surface Wb, the control unit 62 adjusts the opening degrees of the electromagnetic valves so that the air pressure in the upper space H2 is higher than the air pressure in the lower space H1. This adjustment generates a differential pressure F, which causes the sheet material PT to be attached to the curved surface Wb radially outward from the contact area M1. Note that in this modified example in which the differential pressure Fb is generated, the protrusions V may also be formed by causing the deforming member 63 to press the sheet material PT with the differential pressure Fb.

[0157] (8) In each of the embodiments, one workpiece W is stored inside the chamber 17 and the sheet material PT is attached thereto, but this is not limited to this. That is, the sheet material PT may be attached to a state in which multiple workpieces W are stored inside the chamber 17. In this modified example, multiple holding tables 31 are arranged inside the lower housing 22 according to the number of workpieces W, and multiple deformable members 63 are arranged inside the upper housing 20 according to the number of workpieces W. In this modified example, as shown in FIG. 33 , two holding tables 31A and 31B are arranged in the lower housing 22, and two deformable members 63A and 63B are arranged in the upper housing 20.

[0158] In this modified example, when the chambers 17 are formed, the positions at which the holding tables 31 and the positions at which the deforming members 63 are arranged are adjusted in advance so that the deforming members 63 are respectively arranged above the holding tables 31. Specifically, it is preferable that the respective arrangement positions are adjusted so that the deforming member 63A contacts the deepest part Wc of the workpiece W held on the holding table 31A, and the deforming member 63B contacts the deepest part Wc of the workpiece W held on the holding table 31B. In this modified example, the sheet material PT can be bonded to multiple workpieces W simultaneously, thereby improving bonding efficiency.

[0159] (9) In each embodiment, the workpiece W has one curved surface Wb, but this is not limited to this. That is, the configuration of the present invention can also be applied to a workpiece W having multiple curved surfaces Wb. In this modified example, as shown in FIG. 34, the workpiece W has three curved surfaces Wb. The curved surfaces Wb are distinguished from the left as Wb1, Wb2, and Wb3.

[0160] In a workpiece W having a plurality of curved surfaces Wb, the portions connecting the curved surfaces Wb are referred to as curved surface connection portions G. In this modification, the curved surface connection portion G connecting the curved surface Wb1 and the curved surface Wb2 is given the symbol G1, and the curved surface connection portion G connecting the curved surface Wb2 and the curved surface Wb3 is given the symbol G2 to distinguish between the two.

[0161] In this modification, the shape of the workpiece placing surface 35 is adjusted in accordance with the shape of the workpiece W having three curved surfaces Wb. In addition, a plurality of deforming members 63, i.e., deforming members 63A, 63B, and 63C, corresponding to the number of curved surfaces Wb, are disposed on the upper housing 20.

[0162] In this modified example, the position of the workpiece mounting surface 35 and the positions at which the deforming members 63 are disposed are adjusted in advance so that the deforming members 63 are disposed above each of the curved surfaces Wb when the chamber 17 is formed. That is, the deforming member 63A is disposed at a position where it can contact the curved surface Wb1, the deforming member 63B is disposed at a position where it can contact the curved surface Wb2, and the deforming member 63C is disposed at a position where it can contact the curved surface Wb3.

[0163] Specifically, it is preferable to adjust the positions of the deforming members 63A and 63B so that they contact the deepest portion Wc1 of the curved surface Wb1, the deepest portion Wc2 of the curved surface Wb2, and the deepest portion Wc3 of the curved surface Wb3. This configuration allows the protrusions V formed by the deforming members 63 to contact the respective deepest portions Wc. By performing the bonding process using differential pressure F with this contact in place, it is possible to more reliably prevent air from being trapped between the sheet material PT and the workpiece W. This avoids the occurrence of wrinkles or air bubbles in the sheet material PT, allowing the sheet material PT to be adhered to the curved surface Wb with high precision.

[0164] Furthermore, in this modified example, it is preferable that the height of each of the curved connection portions G is configured to be lower than the height of the peripheral edge portion Wa when the workpiece W is held by the holding table 31. With this configuration, when each of the protrusions V is brought into contact with each of the curved surfaces Wb, it is possible to more reliably prevent the sheet material PT in the portions other than the protrusions V from coming into contact with the curved connection portions G, which would cause tension in the sheet material PT.

[0165] In this modification, it is preferable to bring each of the protrusions V into contact with each of the curved surfaces Wb in a state in which the air pressure in the lower space H1 is higher than the air pressure in the upper space H2 to generate a pressure difference Fb, as described above in the modification according to (7). The generation of the pressure difference Fb deforms the sheet material PT so as to move it away from the workpiece W, so that it is possible to more reliably prevent the sheet material PT from coming into contact with the peripheral edge portion Wa or the curved surface connecting portion G in the process of bringing the protrusions V into contact with the curved surfaces Wb.

[0166] (10) In each embodiment, the configuration is not limited to bringing the protrusion V into contact with the curved surface Wb by lowering the deformation member 63. In other words, the holding table 31 holding the workpiece W may be raised to bring the protrusion V into contact with the curved surface Wb.

[0167] (11) In each embodiment, the location of the heater 43 is not limited to the inside of the workpiece holding portion 33, and can be changed as appropriate as long as it heats the workpiece W or the sheet material PT. In addition, the timing of heating by the heater 43 can be changed as appropriate.

[0168] It is preferable to use a heater to heat at least one of the contact process in step S3 and the attachment process in step S4. During these processes, an operation to deform the sheet material PT is performed. By heating the sheet material PT, the base material Ta and the adhesive material Tb become soft and easily deformable. Therefore, the contact process or the attachment process can be more suitably performed.

[0169] (12) In each embodiment, the entire central portion Cp of the surface W1 of the workpiece W is illustrated as a curved surface Wb. However, this is not limited to this. Another example of the shape of the central portion Cp is a configuration in which only a portion of the central portion Cp is curved. That is, as shown in FIG. 35(a), the configuration of the present invention can be applied to a workpiece W in which the central portion Cp of the surface W1 has a curved surface Wb and a flat surface St. In this modified example, the process of attaching the sheet material PT in step S4 is started with the protrusion V in contact with at least a portion of the central portion Cp of the surface W1. That is, in step S3, the protrusion V may be in contact with a portion of the curved surface Wb, or with a portion of the flat surface St. The protrusion V may also be in contact with a portion of the curved surface Wb and a portion of the flat surface St.

[0170] Furthermore, the shape of the central portion Cp is not limited to a configuration having only a single curved surface Wb. That is, as shown in FIG. 33(b), the central portion Cp may have a concave curved surface Wb and a recessed portion Ht. The shape of the recessed portion Ht is not limited to a substantially hemispherical curved surface having a curvature different from that of the curved surface Wb as shown in FIG. 35(b), but may be any shape. Examples of the shape of the recessed portion Ht include a conical recess, a pyramidal recess, a cylindrical recess, and a prismatic recess.

[0171] The shape of the central portion Cp may have a concave curved surface Wb and a convex portion Gt, as shown in Figure 35(c). The shape of the convex portion Gt may be any shape. Examples of the shape of the convex portion Gt include a substantially hemispherical shape, a conical shape, a pyramidal shape, a cylindrical shape, and a prismatic shape. The central portion Cp may also have a curved surface Wb, a concave portion Ht, and a convex portion Gt.

[0172] (13) In each of the examples, the front surface W1 and the back surface W2 of the workpiece W are both curved, but this is not limiting. That is, as shown in FIG. 36, the back surface W2 may be flat. If the back surface W2 is flat, the workpiece W can be held on the holding table 31 in a more stable state. Therefore, the sheet material PT can be more suitably attached to the side of the front surface W1 having the curved surface Wb.

[0173] DESCRIPTION OF SYMBOLS 1 ... Sheet material joining device 2 ... Sheet supply section 3 ... Separator recovery section 4 ... Sheet joining unit 5 ... Sheet recovery section 6 ... Supply bobbin 7 ... Tensioning mechanism 13 ... Dancer roller 14 ... Guide roller 15 ... Recovery bobbin 17 ... Chamber 18 ... Sheet joining mechanism 19 ... Nip roller 20 ... Upper housing 21 ... Sheet cutting mechanism 22 ... Lower housing 29 ... Joining section 30 ... Joining section 31 ... Holding table 33 ... Workpiece holding section 35 ... Workpiece placing surface 41 ... Support pin 43 ... Heater 55 ... Vacuum device 62 ... Control section 63 ... Deformation member 65 ... Cylinder 67 ... Feed roller 68 ... Pinch roller 69 ... Guide rail 75 ... Cutter unit 81 ... Cutter 83 ... Recovery bobbin 91 ... Base end part 93... Tip part 95... Contact surface

Claims

1. A sheet material application device for applying a sheet material to a curved surface of a workpiece, comprising: a holding table for holding the workpiece with the curved side facing upward; a chamber which is partitioned into an upper space and a lower space via the sheet material by sandwiching the sheet material between an upper chamber and a lower chamber, and which stores the holding table in the lower space; a supply mechanism for supplying the sheet material; a deformation member which has a contact surface and which deforms the sheet material by bringing the contact surface into contact with the sheet material; a deformation member moving mechanism which moves the deformation member close to the holding table with the deformation member in contact with the sheet material, and brings the sheet material deformed by the deformation member into close proximity to or into contact with at least a portion of the curved surface of the workpiece; and a decompression mechanism which applies a vacuum to at least the lower space of the upper space and the lower space. a joining mechanism which, while the lower space is evacuated to a vacuum and the sheet material is in close proximity to or in contact with a portion of the curved surface of the workpiece, joins the sheet material to the curved surface of the workpiece by a pressure difference formed between the upper space and the lower space in the chamber separated by the sheet material, wherein the curvature of the abutment surface of the deformable member is configured to be greater than the curvature of the curved surface of the workpiece.

2. In the sheet material joining device according to claim 1, the cross-sectional width a of the contact surface of the deformable member and the cross-sectional width b of the curved surface of the workpiece are A sheet material joining device characterized by satisfying the above conditions.

3. A sheet material joining device as described in claim 1 or claim 2, further comprising an air pressure adjustment mechanism for adjusting the air pressure in the lower space so that it is higher than the air pressure in the upper space, and wherein, when the air pressure in the lower space is adjusted by the air pressure adjustment mechanism so that it is higher than the air pressure in the upper space, the deformation member moving mechanism brings the sheet material deformed by the deformation member close to or into contact with at least a portion of the curved surface of the workpiece.

4. A sheet material joining device as described in claim 1 or claim 2, characterized in that the joining mechanism joins the sheet material to the curved surface of the workpiece by using a pressure difference formed between an upper space and a lower space in the chamber separated by the sheet material, with the sheet material abutting against a portion of the curved surface of the workpiece.

5. A sheet material joining device as described in claim 1 or 2, characterized in that the deformation member has an elastic body on the contact surface, and the sheet material is deformed by bringing the elastic body into contact with the sheet material.

6. A sheet material joining device as described in claim 1 or claim 2, characterized in that the work has a concave curved surface, and the deformation member moving mechanism brings the sheet material deformed by the deformation member close to or into contact with an area including the deepest part of the concave curved surface.

7. A sheet material joining device as claimed in claim 1 or 2, characterized in that the sheet material comprises a sheet piece having a predetermined shape corresponding to the shape of the workpiece and a long carrier tape that holds the sheet piece.

8. A sheet material applying method for applying a sheet material to a curved surface of a workpiece in an internal space of a chamber having an upper chamber and a lower chamber, comprising: a workpiece holding step for holding the workpiece on a holding table with the curved surface facing upward; a top and bottom space forming step for storing the holding table and sandwiching the sheet material between the upper chamber and the lower chamber, thereby dividing the internal space of the chamber into a lower space in which the workpiece is placed with the curved surface facing upward, and an upper space facing the lower space via the sheet material; a supply step for supplying the sheet material; a deformation step for deforming the sheet material by bringing a deformation member having an abutment surface into contact with the sheet material; a deformation member moving step for moving the deformation member close to the holding table with the deformation member in contact with the sheet material, and bringing the sheet material deformed by the deformation member into close proximity to or abutting at least a portion of the curved surface of the workpiece; and a depressurization step for vacuuming at least the lower space of the upper space and the lower space. a bonding process in which, while the lower space is evacuated to a vacuum and the sheet material is close to or abutting a portion of the curved surface of the workpiece, the sheet material is bonded to the curved surface of the workpiece by the pressure difference formed between the upper space and the lower space in the chamber separated by the sheet material, wherein the curvature of the abutment surface of the deformable member is configured to be greater than the curvature of the curved surface of the workpiece.

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