Heating width determination method and method for temporarily welding fiber bundles

Abstract

This heating width determination method determines the width of a fiber bundle heating region when strip-shaped fiber bundles impregnated with a resin are arranged side by side and laminated on a lamination surface. This heating width determination method comprises: a preparing step for preparing welding temperature information pertaining to a welding temperature at which a first fiber bundle and a second fiber bundle adjacent to the first fiber bundle are to be welded, and temperature drop information pertaining to a relation between the distance from a heating position when the fiber bundles are heated at a predetermined target temperature and the degree to which the temperature of the fiber bundles drops in accordance with the distance; and a determining step for using the prepared welding temperature information and temperature drop information to determine, as the width of a heating region of the fiber bundles to be heated to the target temperature, a width by which the first fiber bundle and the second fiber bundle are not welded when the first fiber bundle and the second fiber bundle are heated side by side in the width direction.

Description

Heating Width Determination Method and Temporary Welding Method of Fiber Bundles

[0001] The present disclosure relates to a heating width determination method and a temporary welding method of fiber bundles.

[0002] U.S. Patent Application Publication No. 2021 / 020613 discloses a method for arranging fiber bundles in which strip-shaped fiber bundles impregnated with a resin material are arranged side by side on a placement surface, the arranged fiber bundles are heated individually, and the arranged fiber bundles are welded together in multiple layers to form a laminate.

[0003] The fiber bundles are welded to the laminate such that the fiber bundles, which are a part of the laminate, do not peel off from the laminate during conveyance of the laminate or the like. However, when the position of the welded fiber bundle is different from the预定位置, the welded fiber bundle may be manually peeled off by an operator and re-welded after being repositioned at the预定位置. In this way, the welding of the fiber bundle to the laminate such that the fiber bundle does not peel off from the laminate and the operator can manually peel off the fiber bundle from the laminate is also called temporary welding. The peeling of the temporarily welded fiber bundle and re-welding it to the laminate is also called repositioning. <000 (It seems there is a typo here, should it be

[0004] ?) If adjacent fiber bundles are welded together during temporary welding, it may become difficult to reposition each fiber bundle to an appropriate position. Therefore, in the temporary welding of fiber bundles, a technique that can weld the fiber bundles to the extent that they do not peel off from the laminate and can manually peel off and reposition the fiber bundles is desired.

[0005] The present disclosure can be realized in the following forms.

[0006] According to a first embodiment of the present disclosure, a heating width determination method is provided for determining the width of a heating region of a fiber bundle when a strip-shaped fiber bundle impregnated with resin is laid side by side on a laminated surface. This heating width determination method includes a preparation step of preparing welding temperature information relating to the welding temperature at which a first fiber bundle and a second fiber bundle adjacent to the first fiber bundle are welded together, and temperature drop information relating to the relationship between the distance from the heating position when the fiber bundle is heated at a predetermined target temperature and the degree of temperature drop of the fiber bundle according to the distance, and a determination step of using the prepared welding temperature information and temperature drop information to determine the width of the heating region of the fiber bundle that is heated to the target temperature, such that the first fiber bundle and the second fiber bundle do not weld together when the first fiber bundle and the second fiber bundle are heated side by side in the width direction.

[0007] An explanatory diagram showing the configuration of the fiber bundle placement device. An explanatory diagram showing the functional configuration of the controller and placement head. An explanatory diagram showing the irradiation area of ​​the laser light from the irradiation device. An explanatory diagram showing an example of welding temperature information and temperature drop information. An explanatory diagram showing an example of tacking force information and pressing force information. A flowchart showing the fiber bundle pre-welding method according to the first embodiment of this disclosure. A first flowchart showing the details of the decision process. A second flowchart showing the details of the decision process.

[0008] A. First Embodiment: Figure 1 is an explanatory diagram showing the configuration of the fiber bundle placement apparatus 100. As shown in Figure 1, the fiber bundle placement apparatus 100 places fiber bundles 10 on the laminated surface 52 on the base material 50 which is the target for placement of the fiber bundles 10, and repeatedly places new fiber bundles 10 on top of the placed fiber bundles 10 and pre-welds them, thereby forming a laminate for forming a fiber-reinforced plastic (FRP) part having a desired shape. The base material 50 is, for example, a metal or resin mold having a three-dimensional shape. The fiber bundle placement apparatus 100 is also sometimes called an AFP (Auto Fiber Placement) apparatus, an ATL (Auto Tape Layup) apparatus, or an ATW (Auto Tape Welding) apparatus.

[0009] The fiber bundle 10 is a material formed in a strip shape by impregnating a bundle of reinforcing fibers, such as carbon fibers or glass fibers, with a resin material. The fiber bundle 10 is sometimes also called a tow prepreg or prepreg tape. In this embodiment, a thermoplastic resin that softens when heated is used as the resin material for impregnation. However, instead of a thermoplastic resin, a thermosetting resin that hardens when heated may be used for the resin material of the fiber bundle 10.

[0010] The fiber bundle placement device 100 comprises a controller 80, a supply device 30, an articulated robot 40, and a placement head 60. The controller 80 works in cooperation with the supply device 30, the articulated robot 40, the placement head 60, and the irradiation device 70 to temporarily weld the fiber bundle 10 to the lamination surface 52 on the substrate 50, or to another fiber bundle 10 already placed on the lamination surface 52. In this disclosure, placing the fiber bundle 10 on the lamination surface 52 on the substrate 50, and placing it on another fiber bundle 10 already placed on the lamination surface 52 and temporarily welding them are collectively referred to as laminating the fiber bundle 10 to the lamination surface 52. In this disclosure, the surface on the substrate 50 and the surface formed by another fiber bundle 10 already laminated on the substrate 50 or on the fiber bundle 10 may collectively be referred to as the lamination surface 52.

[0011] The supply device 30 supplies the fiber bundles 10 to the placement head 60. The supply device 30 includes a plurality of bobbins on which the fiber bundles 10 are wound. In this embodiment, the supply device 30 has eight bobbins. That is, the fiber bundle placement device 100 can place and pre-weld eight fiber bundles 10 simultaneously.

[0012] The placement head 60 is attached to the tip of the arm of the articulated robot 40. The articulated robot 40 moves the placement head 60 in a predetermined direction relative to the base material 50. The placement head 60 places the eight fiber bundles 10 supplied from the supply device 30 in a line on the laminated surface 52 on the base material 50 or on another fiber bundle 10 already placed on the laminated surface 52. The placement head 60 is equipped with an irradiation device 70. The irradiation device 70 temporarily welds the fiber bundles 10 placed on the laminated surface 52 or on another fiber bundle 10 already placed on the laminated surface 52. The fiber bundles 10 may be arranged so that the widthwise ends of adjacent fiber bundles 10 overlap, or they may be arranged so that they do not overlap by spacing adjacent fiber bundles 10 apart from each other.

[0013] Figure 2 is an explanatory diagram showing the functional configuration of the controller 80 and the placement head 60. As shown in Figure 2, the placement head 60 includes an introduction roller 62, a delivery mechanism 64, a cutting device 66, a guide roller 67, and a pressing roller 68. The introduction roller 62 guides the fiber bundle 10 supplied from the supply device 30 into the placement head 60. In the path through which the fiber bundle 10 is delivered, the side closer to the supply device 30 is called the upstream side, and the side closer to the pressing roller 68 is called the downstream side.

[0014] The feeding mechanism 64 is located on the laminated surface 52 side of the base material 50, i.e., downstream side, of the introduction roller 62. The feeding mechanism 64 feeds the fiber bundle 10 downstream. The feeding mechanism 64 comprises a driven roller 642, a drive roller 644, and a drive motor 646. The drive motor 646 rotates the drive roller 644 under the control of the controller 80. The rotation of the drive roller 644 causes the driven roller 642 to rotate in response. The fiber bundle 10, held between the driven roller 642 and the drive roller 644, is fed toward the downstream guide roller 67.

[0015] The cutting device 66 is located downstream of the feeding mechanism 64 and is provided between the feeding mechanism 64 and the guide roller 67. The cutting device 66 cuts the fiber bundle 10. The cutting device 66 comprises a cutter 664 and a fixing device 662. The fiber bundle 10 is cut to a predetermined length by the cutter 664, which is moved toward the fixing device 662 by a drive mechanism.

[0016] The guide roller 67 directs the fiber bundle 10 in a direction substantially perpendicular to the direction of movement from the delivery mechanism 64, guiding it to the pressing roller 68. As a result, the fiber bundle 10 is directed by the guide roller 67 to a direction substantially parallel to the lamination surface 52 and guided to the pressing roller 68. That is, the fiber bundle 10 supplied from the supply device 30 to the placement head 60 passes through the introduction roller 62 and the delivery mechanism 64, is directed by the guide roller 67, and reaches the pressing roller 68. The fiber bundle 10 between the guide roller 67 and the pressing roller 68 is positioned to face the lamination surface 52.

[0017] The pressing roller 68 is supported by the placement head 60 via a pressing mechanism. The pressing roller 68 is sometimes also called a compaction roller. The rotation axis of the pressing roller 68 is approximately parallel to the rotation axis of the guide roller 67. The pressing roller 68 generates an arbitrary pressing force in the direction toward the base material 50 via the pressing mechanism. The pressing roller 68 presses the fiber bundle 10, which has been deflected by the guide roller 67, against the lamination surface 52, or against another fiber bundle 10 already placed on the lamination surface 52. Hereafter in this disclosure, pressing the fiber bundle 10 against the lamination surface 52 on the base material 50, and pressing it against another fiber bundle 10 already placed on the lamination surface 52, will be collectively expressed as pressing the fiber bundle 10 against the lamination surface 52. In this embodiment, the guide roller 67 also generates a pressing force in the direction toward the base material 50 via a pressing mechanism, similar to the pressing roller 68.

[0018] In this specification, for the sake of clarity, the direction of movement of the placement head 60 relative to the base material 50 is defined as the front-rear direction of the fiber bundle placement device 100. Of the front-rear direction, the side where the guide roller 67 is located is defined as the front, and the side where the pressing roller 68 is located is defined as the rear. Of the directions perpendicular to the front-rear direction, the direction where the base material 50 is located is defined as the lower side, and the direction where the placement head 60 is located is defined as the upper side. The vertical direction substantially coincides with the thickness direction of the fiber bundle 10. Furthermore, the direction perpendicular to the front-rear direction and the vertical direction is defined as the left-right direction. The left-right direction is sometimes also called the width direction.

[0019] An irradiation device 70 is positioned between the guide roller 67 and the pressing roller 68. In this embodiment, the irradiation device 70 is a laser irradiation device. Under the control of the controller 80, the irradiation device 70 irradiates the target with infrared laser light oscillated by a laser diode. The irradiation device 70 is equipped with an optical element for focusing the infrared laser light onto the surface of the target. As shown in Figure 2, the irradiation device 70 irradiates the fiber bundle 10, which is pressed by the guide roller 67 and the pressing roller 68 and placed on the laminated surface 52 or on another fiber bundle 10 already placed on the laminated surface 52, with infrared laser light to heat it to a predetermined target temperature required for temporary welding. In this embodiment, the irradiation device 70 irradiates the fiber bundle 10 with infrared laser light on the side of the fiber bundle 10 that is opposite to the side facing the laminated surface 52 or another fiber bundle 10 already placed on the laminated surface 52.

[0020] Figure 3 is an explanatory diagram showing the irradiation area of ​​the laser light from the irradiation device 70. Figure 3 shows the fiber bundle 10 viewed from above along the vertical direction. In this embodiment, the irradiation device 70 is equipped with eight laser light sources, corresponding to the eight fiber bundles 10 supplied from the supply device 30. These laser light sources are arranged side by side in the width direction.

[0021] Figure 3 shows the irradiation area LR of the infrared laser light from the irradiation device 70. Hatching is applied to the irradiation area LR to facilitate understanding of the technology. The irradiation area LR substantially coincides with the heating area where the fiber bundle 10 is heated. As shown in Figure 3, the irradiation device 70 is configured such that the irradiation area LR, which irradiates the target with infrared laser light, is substantially rectangular in shape, using an optical lens.

[0022] Figure 3 shows the irradiation width WT, which is the width of the infrared laser light emitted by the irradiation device 70 in the left-right direction. The irradiation width WT is approximately equal to the width of the heating area of ​​the fiber bundle 10. In this embodiment, the irradiation device 70 can switch the irradiation width WT to any width by adjusting the optical system, such as the optical path of the laser light. The controller 80 sets the irradiation width WT of the fiber bundle 10 by the irradiation device 70 to be smaller than the width of the fiber bundle 10. In this embodiment, the controller 80 sets the irradiation width WT to be approximately 80% of the width of the fiber bundle 10. Instead of adjusting the optical system, the irradiation device 70 may switch the irradiation width WT by adjusting the number of spots irradiating with laser light, for example, by using multiple spot laser light sources arranged in the width direction. The irradiation device 70 may also be a device that heats the fiber bundle 10 using something other than laser light. The irradiation device 70 may also be a device in which the irradiation width WT cannot be changed.

[0023] The longitudinal direction of the irradiation area LR coincides with the front-to-back direction. The irradiation time during which the irradiation device 70 irradiates infrared laser light to a predetermined position on the fiber bundle 10 is obtained by dividing the length of the irradiation area LR in the front-to-back direction by the transport speed of the fiber bundle 10 by the delivery mechanism 64. The controller 80 controls the irradiation time by controlling the delivery mechanism 64 and adjusting the movement speed of the fiber bundle 10.

[0024] The controller 80 arbitrarily sets the output of the irradiation device 70 when heating the fiber bundle 10. In this embodiment, the controller 80 adjusts the output of the irradiation device 70 by controlling the light density of the infrared laser light per unit area. With the above configuration, the controller 80 controls the amount of heat that the infrared laser light delivers to a predetermined position on the fiber bundle 10 by controlling the movement speed of the fiber bundle 10 by the delivery mechanism 64 and the output of the irradiation device 70. When raising the temperature of a predetermined position on the fiber bundle 10 to a target temperature, for example, when it is necessary to set the transport speed of the fiber bundle 10 by the delivery mechanism 64 to a relatively slow setting, the controller 80 reduces the output of the irradiation device 70 to raise the temperature of the predetermined position on the fiber bundle 10 to the target temperature.

[0025] Referring to Figure 2, the internal functional configuration of the controller 80 will be described. As shown in Figure 2, the controller 80 is a computer that includes a CPU 82 as a processor, a storage device 84 including ROM and RAM, and a communication unit 86 for communicating with the server 90. These are connected bidirectionally by an internal bus.

[0026] The storage device 84 stores programs for executing each function realized by the fiber bundle arrangement apparatus 100 according to this embodiment. The CPU 82 reads and executes the programs stored in the storage device 84, thereby enabling the controller 80 to implement the functions for determining the heating width and pre-welding the fiber bundle according to this embodiment.

[0027] As shown in Figure 2, the storage device 84 stores various types of information used to set conditions for realizing the heating width determination method and the fiber bundle temporary welding method according to this embodiment. More specifically, the storage device 84 stores welding temperature information 842, temperature drop information 844, shape information 846, arrangement direction information 848, tacking force information 850, and pressing force information 852. This information is prepared in advance before the temporary welding of the fiber bundle 10 by the fiber bundle arrangement device 100 is performed. The prepared information is stored in a server 90 or the like. When the controller 80 performs the temporary welding of the fiber bundle 10 by the fiber bundle arrangement device 100, it obtains, for example, one of the welding temperature information 842, temperature drop information 844, shape information 846, arrangement direction information 848, tacking force information 850, or pressing force information 852, or a combination of these, from the server 90 via wireless communication or wired communication via the communication unit 86.

[0028] The welding temperature information 842 is information regarding the welding temperature at which the fiber bundles 10 weld together. The welding temperature information 842 is set for each manufacturing condition, such as the material, size, and shape that make up the fiber bundle 10. As shown in Figure 3, one fiber bundle 10 among the fiber bundles 10 arranged in the width direction is defined as the first fiber bundle, and the fiber bundle 10 adjacent to the first fiber bundle is defined as the second fiber bundle. When the first fiber bundle and the second fiber bundle are in contact, and the end of the first fiber bundle or the second fiber bundle in the width direction is heated to the welding temperature, the contact portion where the first fiber bundle and the second fiber bundle are in contact with each other will weld together. In this case, for example, the first fiber bundle and the second fiber bundle may not be able to be separated and may not be able to be individually rearranged on the laminated surface 52. For this reason, for example, it is preferable that the temperature at both ends of the fiber bundle 10 in the width direction be controlled to be below the welding temperature in order to avoid welding with adjacent fiber bundles 10. By controlling the temperature of both ends of the fiber bundle 10 in the width direction to be below the welding temperature, it is possible to suppress or prevent the problem of the first fiber bundle and the second fiber bundle becoming unable to be individually rearranged on the laminated surface 52 due to welding of the first fiber bundle and the second fiber bundle.

[0029] The temperature drop information 844 is information regarding the temperature gradient of the fiber bundle 10 in the width direction. The temperature drop information 844 is set for each manufacturing condition, such as the material constituting the fiber bundle 10, the width of the fiber bundle 10, and the thickness of the fiber bundle 10. The position of the fiber bundle 10 heated by the irradiation device 70 is defined as the heating position. In this embodiment, the heating position coincides with the heating region of the fiber bundle 10 by the irradiation device 70. The temperature drop information 844 is the rate of change in temperature of the fiber bundle 10 between the heating position when the heating position is heated to a predetermined target temperature and a position further away from the heating position in the width direction. That is, the temperature drop information 844 is information regarding the relationship between the distance from the heating region when the fiber bundle 10 is heated to the target temperature and the degree of temperature drop of the fiber bundle 10 corresponding to that distance.

[0030] Figure 4 is an explanatory diagram showing an example of welding temperature information 842 and temperature drop information 844. The horizontal axis in Figure 4 shows the distance from one end E1 of the fiber bundle 10 in the width direction. The right end of the horizontal axis is the other end E2 of the fiber bundle 10. The vertical axis shows the temperature of the fiber bundle 10. The data shown in Figure 4 can be prepared in advance by experiments using the fiber bundle placement device 100.

[0031] Figure 4 shows four graphs G1, G2, G3, and G4. Each graph has a different heating region width. Each heating region is set to include the center CP of the fiber bundle 10 in the width direction. Graph G1 shows the result when the width of the heating region by the irradiation device 70 is set to approximately 40% of the width of the fiber bundle 10, as indicated by the dashed line. In other words, graph G1 shows the temperature gradient when a heating region with a width WT1, which is approximately 20% of the total width of the fiber bundle 10, is heated to the target temperature T1 by the irradiation device 70. Note that the ratio of the heating region width to the total width of the fiber bundle 10 in each graph is just an example to facilitate explanation.

[0032] Graph G2 shows the temperature gradient when a heating region with a width WT2, which is approximately 40% of the total width of the fiber bundle 10, is heated to the target temperature T1, indicated by a dashed line. Graph G3 shows the temperature gradient when a heating region with a width WT3, which is approximately 60% of the total width of the fiber bundle 10, is heated to the target temperature T1, indicated by a solid line. Graph G4 shows the temperature gradient when a heating region with a width WT4, which is approximately 80% of the total width of the fiber bundle 10, is heated to the target temperature T1, indicated by a dashed line. As shown in graphs G1, G2, G3, and G4, the temperature of the fiber bundle 10 decreases as you move away from the heating region. However, even at positions away from the heating region, the temperature of the fiber bundle 10 rises above the temperature before heating due to heat transfer from the heating region. Therefore, the temperature of the fiber bundle 10 at the ends in the width direction may exceed the welding temperature when the temperature of the heating region reaches the target temperature T1.

[0033] Figure 4 shows the welding temperature TH. If the temperature of the part of the fiber bundle 10 that is outside the heating region in the width direction exceeds the welding temperature TH, the fiber bundles 10 may weld together at the contact point where the end of the fiber bundle 10 in the width direction and the end of another fiber bundle 10 adjacent to it come into contact. In this embodiment, the width of the heating region is set so that the temperature of the end of the fiber bundle 10 in the width direction is below the welding temperature. Also, for example, if the shape of the part to be manufactured has a complex shape such as a curved surface, it is preferable that the width of the heating region of the fiber bundle 10 be relatively large. For this reason, in the example in Figure 4, based on graph G3, a width WT3 which is approximately 60% of the total width of the fiber bundle 10 is set as the width of the heating region in the manufacturing conditions. In other words, in the example in Figure 4, a width WT3 which is the condition in which the temperature of one end E1 and the other end E2 of the fiber bundle 10 is below the welding temperature TH and the width of the heating region is maximized is a suitable setting for the width of the heating region.

[0034] Returning to Figure 2, the shape information 846 is information regarding the shape of the laminated surface 52 of the base material 50. The shape information 846 includes information on whether or not the laminated surface 52 is flat. Here, if the laminated surface 52 is not flat, such as when it has an uneven shape or is curved, the pre-welded fiber bundle 10 is more likely to peel off from the laminated surface 52 or other fiber bundles 10 already placed on the laminated surface 52, compared to when the laminated surface 52 is flat. This is because the fiber bundle 10 is a strip-shaped material. For these reasons, when the laminated surface 52 is not flat, it is preferable to set the width of the heating area larger than when the laminated surface 52 is flat in order to pre-weld with the same quality as when the laminated surface 52 is flat. Note that the shape information 846 may be binary data indicating whether or not the laminated surface 52 is flat, or it may be three-dimensional coordinate data based on the shape of the laminated surface 52 of the base material 50. If the shape information 846 is three-dimensional coordinate data, the shape information 846 may be used for controlling the position and orientation of the placement head 60 by the controller 80.

[0035] The arrangement direction information 848 is information regarding the arrangement direction of the fiber bundles 10. The arrangement direction information 848 includes both information regarding the arrangement direction of the fiber bundles 10 in a predetermined layer where the fiber bundles 10 are temporarily welded, and information regarding the arrangement direction of the fiber bundles 10 in layers below that layer. In a laminate formed by the arrangement of fiber bundles 10 and a second layer laminated on the first layer, the direction in which the fibers of the fiber bundles 10 in the first layer extend is defined as the first direction, and the direction in which the fibers of the fiber bundles 10 in the second layer extend is defined as the second direction. Heat is transferred more easily between fibers within a fiber bundle 10 than between fibers and other materials. When arranging the fiber bundles 10 of the second layer, if the second direction is substantially parallel to the first direction, the proportion of contact between the fibers in the fiber bundles 10 of the first layer and the fibers in the fiber bundles 10 of the second layer is greater than when the second direction is not substantially parallel to the first direction. For the reasons stated above, when the second direction is substantially parallel to the first direction, heat transfer between the fiber bundles 10 is easier than when the second direction is not substantially parallel to the first direction. Therefore, it is conceivable to correct the output of the fiber bundle arrangement device 100 during heating to a lower output when the second direction is substantially parallel to the first direction than when the second direction is not parallel to the first direction.

[0036] The tacking force information 850 is information relating to the relationship between the heating temperature when the fiber bundle 10 is heated and temporarily welded to the laminated surface 52 and the tacking force. Tacking force is the force required by the operator to peel the fiber bundle that has been temporarily welded to the laminated surface 52 away from the laminated surface 52. Tacking force is sometimes also called adhesive force, peel strength, or bonding strength. The unit of tacking force is, for example, Newtons (N). The pressing force information 852 is information relating to the relationship between the tacking force and the pressing force applied to the fiber bundle by the pressing mechanism. The pressing force information 852 can be prepared in advance by experiments using samples prepared using the fiber bundle placement device 100.

[0037] Figure 5 is an explanatory diagram showing an example of tacking force information 850 and pressing force information 852. The horizontal axis of Figure 5 shows the heating temperature when the fiber bundle 10 is heated and temporarily welded to the laminated surface 52, and the vertical axis shows the tacking force required to peel off the fiber bundle 10. The tacking force can be obtained, for example, by a 90-degree peel test. In a 90-degree peel test, the test apparatus or test vehicle pulls the fiber bundle 10 from the laminated surface 52 at a constant speed so that the direction in which the fiber bundle 10 is peeled off is 90 degrees with respect to the laminated surface 52, and the force at which the fiber bundle 10 is peeled off the laminated surface 52 is measured as the tacking force.

[0038] As shown in Figure 5, in order for the fiber bundle 10 to be properly pre-welded to the laminated surface 52, it is necessary to pre-weld it with a tacking force S1 that is sufficient to prevent the fiber bundle 10 from peeling off the laminate during transport of the laminate. For example, if the fiber bundle 10 is pre-welded with a tacking force less than S1, there is a possibility that the fiber bundle 10 will peel off the laminate during transport of the laminate. Therefore, the tacking force S1 is set as the lower limit of the manufacturing conditions. On the other hand, if the tacking force is too strong, for example, when it becomes necessary to peel and rearrange the fiber bundle due to a manufacturing defect, the operator may not be able to peel the fiber bundle 10 from the laminated surface 52, and the fiber bundle 10 may not be able to be rearranged. Therefore, a tacking force S2 that allows the operator to peel the fiber bundle 10 from the laminated surface 52 is set as the upper limit of the manufacturing conditions. Thus, in this embodiment, the manufacturing conditions are set so that the fiber bundle 10 is pre-welded with a tacking force of S1 or greater and less than S2.

[0039] Figure 5 shows the results of tacking force for each pressing force applied by the pressing roller 68. Specifically, graph G5 shows the tacking force when the pressing force is 0.1 MPa, graph G6 shows the tacking force when the pressing force is 0.2 MPa, and graph G7 shows the tacking force when the pressing force is 0.4 MPa. As shown in Figure 5, even when the heating area is heated to the same temperature, the tacking force when temporary welding is performed with a higher pressing force is stronger than the tacking force when temporary welding is performed with a lower pressing force. For example, consider heating the heating area to a target temperature T1. In this case, if the pressing force is set to 0.4 MPa, the tacking force will be greater than or equal to the tacking force S2, which may prevent the rearrangement of the fiber bundle 10. Therefore, the pressing force can be set to 0.1 MPa or 0.2 MPa. As another example, consider pressing the fiber bundle 10 with a pressing force of 0.4 MPa according to the specifications of the pressing mechanism and the pressing roller 68. In this case, in order to keep the tacking force below the tacking force S2, it is possible to heat the heating region to a temperature below T2, for example, a target temperature T3.

[0040] Figure 6 is a flowchart illustrating a fiber bundle pre-welding method according to the first embodiment of the present disclosure. This flow is initiated, for example, at the start of manufacturing a fiber-reinforced plastic part. In this embodiment, this flow is repeated, for example, each time a fiber bundle 10 is laminated. However, after the preparation step S100 and the determination step S200 have been performed for all layers to be laminated of the fiber bundle 10, the pre-welding step S300 may be performed consecutively for each layer of the fiber bundle 10. Step S100 prepares the information used in the heating width determination method and the fiber bundle pre-welding method according to the present disclosure. Step S100 is a non-limiting example of the preparation step.

[0041] The controller 80, for example, obtains manufacturing conditions corresponding to the product to be manufactured using fiber-reinforced plastic from the server 90 and stores them in the storage device 84. Specifically, the controller 80 obtains welding temperature information 842, temperature drop information 844, shape information 846, arrangement direction information 848, tacking force information 850, and pressing force information 852 from the server 90, corresponding to the product to be manufactured using fiber-reinforced plastic. The preparation process may also include obtaining various data related to the manufacturing conditions of fiber-reinforced plastic through experiments, etc., and storing the obtained data in the server 90.

[0042] In step S200, the width of the heating region for heating the fiber bundle 10, as well as the manufacturing conditions for realizing the heating width determination method and the fiber bundle pre-welding method according to this disclosure, are determined. Step S200 is a non-limiting example of the determination process. Steps S100 and S200 are non-limiting examples of the heating width determination method.

[0043] In step S300, the fiber bundles 10 are placed on the laminated surface 52 of the base material 50, or on another fiber bundle 10 already placed on the laminated surface 52, and pre-welded. More specifically, the heating region of the fiber bundles 10 placed on the laminated surface 52 or on another fiber bundle 10 already placed on the laminated surface 52, having the width determined in step S200, is heated to a target temperature T1. Step S300 is a non-limiting example of the pre-welding process.

[0044] When temporarily welding the fiber bundle 10 to the lamination surface 52 or another fiber bundle 10 already disposed on the lamination surface 52, the controller 80 moves the placement head 60 to a predetermined processing start position. The controller 80 drives the pressing roller 68 and the guide roller 67 of the placement head 60 disposed at the processing start position to press the fiber bundle 10 onto the lamination surface 52 or another fiber bundle 10 already disposed on the lamination surface 52. The controller 80 drives the drive motor 646 of the feeding mechanism 64 to feed the fiber bundle 10 from the supply device 30 at a moving speed corresponding to the irradiation time. The controller 80 controls the irradiation device 70 and moves the placement head 60 while irradiating the heating region of the fiber bundle 10 with infrared laser light.

[0045] The controller 80 moves the placement head 60 while the irradiation device 70 outputs infrared laser light and the pressing roller 68 presses the fiber bundle 10. The fiber bundle 10 heated to the target temperature T1 by the irradiation of the infrared laser light is pressed by the pressing roller 68 toward the lamination surface 52 or another fiber bundle 10 already disposed on the lamination surface 52 with a predetermined pressing force immediately after being heated. As a result, the fiber bundle 10 is temporarily welded to the lamination surface 52 or another fiber bundle 10 already disposed on the lamination surface 52.

[0046] When the placement head 60 moves to the end position of the temporary welding, the controller 80 stops the movement of the placement head 60 by the articulated robot 40. The controller 80 stops the feeding of the fiber bundle 10 by the feeding mechanism 64 and stops the irradiation of the laser light by the irradiation device 70. As a result, one-time temporary welding of the fiber bundle 10 to the lamination surface 52 or another fiber bundle 10 already disposed on the lamination surface 52 is completed.

[0047] FIG. 7 is a first flowchart showing details of the determination step S200. FIG. 8 is a second flowchart showing details of the determination step S200. As shown in FIG. 7, in step S210, the controller 80 checks the pressing force information 852 as manufacturing conditions stored in the storage device 84. Specifically, the controller 80 reads and acquires the pressing force information 852 from the storage device 84. In the present embodiment, the pressing force as manufacturing conditions is, for example, 0.2 MPa. In step S220, the controller 80 checks the tacking force information 850 stored in the storage device 84. Specifically, the controller 80 reads and acquires the tacking force information 850 from the storage device 84.

[0048] In step S230, the controller 80 determines the target temperature as manufacturing conditions using the pressing force information 852 and the tacking force information 850. As shown in FIG. 5, the controller 80 determines the temperature condition that satisfies the condition that the tacking force after temporary welding is not less than the tacking force S1 and less than the tacking force S2 as the manufacturing conditions, and stores the determined temperature condition in the storage device 84 as the manufacturing conditions. In the present embodiment, the controller 80 determines the target temperature T1 shown in FIG. 5 as the temperature condition.

[0049] In step S240, the controller 80 checks the welding temperature information 842 and the temperature drop information 844 stored in the storage device 84. Specifically, the controller 80 reads and acquires the welding temperature information 842 and the temperature drop information 844 from the storage device 84. In step S250, the controller 80 calculates the width of the heating region using the acquired welding temperature information 842 and the temperature drop information 844. Specifically, as shown in FIG. 4, the controller 80 calculates the condition that the temperatures of one end E1 and the other end E2 of the fiber bundle 10 in the width direction are less than the welding temperature TH. In the present embodiment, the controller 80 calculates the width WT3, which is the widest width among them.

[0050] In step S260, the controller 80 checks the shape information 846 stored in the storage device 84. Specifically, the controller 80 reads and obtains the shape information 846 from the storage device 84. In step S262, the controller 80 checks from the obtained shape information 846 whether the laminated surface 52 to which the fiber bundle 10 is to be temporarily welded is flat or not. If the laminated surface 52 is flat (S262: YES), the controller 80 proceeds to step S264. In step S264, the controller 80 sets the width of the heating area to be narrower than the width of the heating area when the laminated surface 52 is curved. In this embodiment, the controller 80 corrects the width of the heating area calculated in step S250 by a predetermined correction value, such as 2%. The controller 80 may also set the output of the irradiation device 70 to be higher. In this case, the controller 80 can increase the transport speed of the fiber bundle 10 by the delivery mechanism 64 in accordance with the increase in output. The productivity of the fiber bundle arrangement device 100 can be improved by increasing the transport speed of the fiber bundle 10 by the delivery mechanism 64. However, the controller 80 may set the width of the heating area to the same width as the width of the heating area when the laminated surface 52 is a curved surface. In step S266, the controller 80 determines the width of the heating area after correction in step S264 as a manufacturing condition and stores the determined manufacturing condition in the storage device 84.

[0051] In step S262, if the stacking surface 52 is flat (S262: NO), the controller 80 proceeds to step S266. In step S266, the controller 80 determines the width of the heating area calculated in step S250 as a manufacturing condition and stores the determined manufacturing condition in the storage device 84.

[0052] As shown in Figure 8, in step S270, the controller 80 checks the arrangement direction information 848 stored in the storage device 84. Specifically, the controller 80 reads and obtains the arrangement direction information 848 from the storage device 84. In step S272, the controller 80 checks whether the arrangement direction of the current fiber bundle 10 is approximately parallel to the arrangement direction of the fiber bundle 10 in the lower layer. In other words, the controller 80 checks whether the arrangement direction of the current fiber bundle 10 is approximately parallel to the arrangement direction of another fiber bundle 10 that has already been stacked. Specifically, the controller 80 reads and compares the arrangement direction of the current fiber bundle 10 as a manufacturing condition stored in the storage device 84 with the arrangement direction of the previous fiber bundle 10 as a past manufacturing history. If the arrangement direction of the fiber bundle 10 in this case is approximately parallel to the arrangement direction of the fiber bundle 10 in the lower layer (S272: YES), the controller 80 moves the process to step S276, determines the output when heating the fiber bundle 10 with the irradiation device 70 to an output as a predetermined standard condition, and stores the determined output as a manufacturing condition in the storage device 84. The controller 80 may, for example, read the arrangement direction of the fiber bundle 10 in the previous layer, which is provided in advance as design information, and compare it with the arrangement direction of the fiber bundle 10 in this case to confirm whether the arrangement direction of the fiber bundle 10 in this case is approximately parallel to the arrangement direction of another fiber bundle 10 that has already been stacked.

[0053] In step S272, if the arrangement direction of the fiber bundle 10 in this step is not parallel to the arrangement direction of the fiber bundle 10 in the lower layer (S272: NO), the controller 80 proceeds to step S274. In step S274, the controller 80 corrects the output, for example, so that the output becomes a value higher than the reference condition. In step S276, the controller 80 determines the corrected output as the manufacturing condition. The controller 80 stores the corrected output as the manufacturing condition in the storage device 84 and ends the determination process.

[0054] As described above, according to the heating width determination method of this embodiment, in the determination step, the width of the heating area is determined to be a width WT3 such that adjacent fiber bundles do not fuse to each other even when the heating area of ​​the fiber bundles arranged in the width direction is heated to the target temperature T1, by using pre-prepared welding temperature information 842 and temperature drop information 844. Therefore, the operator can temporarily weld the fiber bundles 10 to the laminated surface 52 to the extent that they do not peel off from the base material 50, and can suppress or prevent the fiber bundles 10 that are arranged adjacent to each other from fusing. Accordingly, the operator can manually peel off and rearrange the temporarily welded fiber bundles 10 as needed.

[0055] According to the heating width determination method of this embodiment, the determination step includes calculating the temperature of the fiber bundle 10 outside the heating region in the width direction using temperature drop information 844 indicating the degree of temperature decrease of the fiber bundle 10. The determination step also includes comparing the calculated temperature of the fiber bundle 10 outside the heating region with the welding temperature TH to determine the width WT3 of the heating region such that the temperature of the contact portion between adjacent fiber bundles 10 is less than the welding temperature TH. By using the welding temperature information 842 and the temperature drop information 844, the operator can set the width of the heating region to the widest possible width WT3, assuming that the contact portions between the fiber bundles 10 do not weld. Therefore, the operator can firmly pre-weld the fiber bundles 10 to the laminated surface 52 while suppressing or preventing the fiber bundles 10 from welding to each other.

[0056] In the fiber bundle pre-welding method of this embodiment, a laser irradiation device is used as the irradiation device 70 in the pre-welding process. The laser irradiation device allows for arbitrary adjustment of the width WT3 of the heating area by adjusting the irradiation area of ​​the laser beam. Therefore, the operator can switch the width of the heating area in a simple manner. Furthermore, the operator can pre-weld multiple types of fiber bundles 10 with different heating area width conditions using the same irradiation device 70.

[0057] According to the heating width determination method of this embodiment, the determination step includes a step of determining the width of the heating area using the prepared shape information 846. The operator can pre-weld the fiber bundle 10 using manufacturing conditions suitable for each shape of the laminated surface 52.

[0058] According to the heating width determination method of this embodiment, in the determination step, the width of the heating area is determined such that the width of the heating area when the laminated surface 52 is not flat is larger than the width of the heating area when the laminated surface 52 is flat. In the case of a non-planar laminated surface 52 where the temporarily welded fiber bundle 10 is easily peeled off from the laminated surface 52 or another fiber bundle 10 already placed on the laminated surface 52, the width of the heating area is set to be larger. Therefore, the operator can temporarily weld the fiber bundle 10 using manufacturing conditions suitable for each shape of the laminated surface 52.

[0059] According to the fiber bundle pre-welding method of this embodiment, the output of the irradiation device 70 is determined using the arrangement direction information 848. The arrangement direction information 848 is information regarding the arrangement direction of the fiber bundle 10, including a first direction which is the direction in which the fiber bundle 10 extends in the first layer, and a second direction which is the direction in which the fiber bundle 10 extends in the second layer which is the upper layer of the first layer. Therefore, the operator can pre-weld the fiber bundle 10 using suitable manufacturing conditions that correspond to the difference in thermal conductivity caused by the difference in the direction in which the fiber bundle 10 extends in the lower layer and the upper layer.

[0060] According to the fiber bundle pre-welding method of this embodiment, the determination step includes a step of determining the output such that the output when the second direction is parallel to the first direction is lower than the output when the second direction is not parallel to the first direction. In the fiber bundle pre-welding method of this embodiment, the output is determined such that the output of the irradiation device 70 is lower when the second direction is parallel to the first direction and the heating region is easily heated. Therefore, the operator can suppress or prevent variations in the adhesion of the pre-welded fiber bundles 10, even when there are differences in thermal conductivity due to differences in the direction of extension of the fiber bundles 10 between the lower and upper layers.

[0061] According to the heating width determination method of this embodiment, in the determination step, the target temperature T1 is determined using tacking force information 850 so that the tacking force is within a predetermined range. Based on the tacking force, the operator can set manufacturing conditions that allow for the rearrangement of the temporarily welded fiber bundles 10 while suppressing or preventing the detachment of the fiber bundles 10 from the base material 50.

[0062] According to the fiber bundle pre-welding method of this embodiment, in the determination step, the target temperature T1 is determined using pressing force information 852 relating to the relationship between the tacking force S1 and the pressing force. The operator can set manufacturing conditions that allow for the rearrangement of the pre-welded fiber bundles 10 while suppressing or preventing the fiber bundles 10 from falling off the base material 50, based on the tacking force and the pressing force that affects the tacking force.

[0063] B. Other Embodiments: (B1) In the first embodiment described above, an example was shown in which the irradiation device 70 irradiates the fiber bundle 10 with infrared laser light on the side of the fiber bundle 10 opposite to the side facing the laminated surface 52. In contrast, the irradiation device 70 may irradiate the laminated surface 52 or another fiber bundle 10 already placed on the laminated surface 52 with infrared laser light instead of the fiber bundle 10. The irradiation position of the infrared laser light to the laminated surface 52 or another fiber bundle 10 already placed on the laminated surface 52 can be set to any position in front of the guide roller 67, for example. However, the irradiation position of the infrared laser light to the laminated surface 52 or another fiber bundle 10 already placed on the laminated surface 52 is preferably near the guide roller 67 from the viewpoint of suppressing or preventing a temperature drop of the irradiated object. The fiber bundle 10 is heated by coming into contact with the heated laminated surface 52 or another fiber bundle 10 already placed on the laminated surface 52, and is temporarily welded to the laminated surface 52 or another fiber bundle 10 already placed on the laminated surface 52.

[0064] Furthermore, the irradiation device 70 may irradiate the surface of the fiber bundle 10 facing the laminated surface 52 or another fiber bundle 10 already placed on the laminated surface 52 with infrared laser light. For example, by positioning the irradiation device 70 in front of the guide roller 67 and the fiber bundle 10, the irradiation device 70 irradiates the surface of the fiber bundle 10 facing the laminated surface 52 or another fiber bundle 10 already placed on the laminated surface 52 with infrared laser light just before it is turned by the guide roller 67. In this case, the irradiation device 70 may heat the laminated surface 52 or the other fiber bundle 10 already placed on the laminated surface 52, as well as the surface of the fiber bundle 10 facing the laminated surface 52 or another fiber bundle 10 already placed on the laminated surface 52.

[0065] (B2) The fiber bundle arrangement device 100 may be equipped with a plurality of irradiation devices 70. For example, of the two irradiation devices 70, one irradiation device 70 may be placed in front of the guide roller 67, and the other irradiation device 70 may be placed between the guide roller 67 and the pressing roller 68, as in the first embodiment described above. In this case, the other irradiation device 70 irradiates, for example, the surface of the fiber bundle 10 that is opposite to the surface facing the laminated surface 52 or another fiber bundle 10 already placed on the laminated surface 52 with infrared laser light. The one irradiation device 70 irradiates with infrared laser light to any of the following (1) to (3): (1) the laminated surface 52 or another fiber bundle 10 already placed on the laminated surface 52 (2) the surface of the fiber bundle 10 that faces the laminated surface 52 or another fiber bundle 10 already placed on the laminated surface 52 (3) the surface of the fiber bundle 10 that faces the laminated surface 52 or another fiber bundle 10 already placed on the laminated surface 52

[0066] The functions of the elements disclosed herein can be performed using circuits or processing circuits, including general-purpose processors, dedicated processors, integrated circuits, ASICs (Application Specific Integrated Circuits), conventional circuits, and / or combinations thereof, configured or programmed to perform the disclosed functions. A processor is considered a processing circuit or circuit because it includes transistors and other circuits. In this disclosure, a circuit, unit, or means is hardware that performs the enumerated functions, or hardware programmed to perform the enumerated functions. The hardware may be hardware disclosed herein, or other known hardware that is programmed or configured to perform the enumerated functions. If the hardware is a processor, which is considered a type of circuit, then the circuit, means, or unit is a combination of hardware and software, and the software is used to configure the hardware and / or the processor.

[0067] This disclosure is not limited to the embodiments described above, and can be implemented in various forms without departing from its spirit. For example, this disclosure can also be implemented in the following forms (spect). The technical features in the embodiments described above that correspond to the technical features in each of the forms described below can be replaced or combined as appropriate in order to solve some or all of the problems of this disclosure, or to achieve some or all of the effects of this disclosure. Furthermore, if the technical features are not described as essential in this specification, they can be deleted as appropriate.

[0068] (1) According to a first embodiment of the present disclosure, a heating width determination method is provided for determining the width of a heating region of a fiber bundle when a strip-shaped fiber bundle impregnated with resin is laid out on a laminated surface. This heating width determination method includes a preparation step of preparing welding temperature information relating to the welding temperature at which a first fiber bundle and a second fiber bundle adjacent to the first fiber bundle are welded together, and temperature drop information relating to the relationship between the distance from the heating position when the fiber bundle is heated at a predetermined target temperature and the degree of temperature drop of the fiber bundle according to the distance, and a determination step of using the prepared welding temperature information and temperature drop information to determine the width of the heating region of the fiber bundle that is heated to the target temperature, such that the first fiber bundle and the second fiber bundle do not weld together when the first fiber bundle and the second fiber bundle are heated side by side in the width direction. According to this embodiment, an operator can temporarily weld the fiber bundle to the laminated surface to the extent that it does not peel off from the substrate. Furthermore, the operator can suppress or prevent adjacent fiber bundles from welding together, and can manually detach and rearrange temporarily welded fiber bundles.

[0069] (2) In the heating width determination method described in embodiment (1) above, the determination step includes the steps of: calculating the temperature of the fiber bundle outside the heating region in the width direction using the degree of temperature decrease of the prepared fiber bundle; and comparing the calculated temperature of the fiber bundle outside the width direction with the welding temperature to determine the width of the heating region such that the temperature of the contact portion between the first fiber bundle and the second fiber bundle outside the width direction is less than the welding temperature. According to this embodiment, the operator can set the width of the heating region to the widest possible width, on the premise that the contact portions of the fiber bundles do not weld, by using welding temperature information and temperature drop information.Therefore, the operator can firmly pre-weld the fiber bundles to the laminated surface while suppressing or preventing the fiber bundles from welding to each other.

[0070] (3) A fiber bundle pre-welding method comprising: a heating width determination method described in embodiment (1) or embodiment (2) above; and a pre-welding step of placing the fiber bundle on the laminated surface, and heating the heating region of the fiber bundle placed on the laminated surface having the width determined in the determination step to the target temperature to pre-weld the fiber bundle, wherein the pre-welding step is a step of heating the heating region using a device capable of adjusting the width of the heating region. According to this embodiment, an operator can pre-weld multiple types of fiber bundles with different heating region width conditions using the same irradiation device.

[0071] (4) In the heating width determination method described in any of the above embodiments (1) to (3), the preparation step further includes a step of preparing shape information relating to the shape of the laminated surface. The determination step further includes a step of determining the width of the heating region using the prepared shape information. According to this embodiment, the operator can pre-weld the fiber bundles using manufacturing conditions suitable for each shape of the laminated surface.

[0072] (5) In the heating width determination method described in any of the above embodiments (1) to (4), the shape information includes information on whether or not the laminated surface is flat. The determination step includes a step of determining the width of the heating area using the prepared shape information such that the width of the heating area when the laminated surface is not flat is greater than the width of the heating area when the laminated surface is flat. According to this embodiment, the operator can pre-weld the fiber bundles using manufacturing conditions suitable for each shape of the laminated surface.

[0073] (6) A fiber bundle pre-welding method comprising: a heating width determination method according to any of the above embodiments (1) to (5); and a pre-welding step of placing the fiber bundle on the laminated surface, heating the heating region having the width determined in the determination step to the target temperature to pre-weld the fiber bundle, further comprising: arranging the fiber bundle on the laminated surface so that the fiber bundle extends in a first direction to form a first layer; and arranging the fiber bundle on the first layer so that the fiber bundle extends in a second direction to form a second layer. The pre-welding step is a step of heating the heating region using a device capable of adjusting the output when heating the heating region. The preparation step further includes a step of preparing arrangement direction information relating to the arrangement direction of the fiber bundle, including the first direction and the second direction. The determination step determines the output using the prepared arrangement direction information. In this configuration, the operator can pre-weld the fiber bundles using suitable manufacturing conditions that address the difference in thermal conductivity resulting from the difference in the direction of fiber bundle extension between the lower and upper layers.

[0074] (7) In the fiber bundle pre-welding method according to any of the above embodiments (1) to (6), the determination step includes a step of determining the output such that the output when the second direction is parallel to the first direction is lower than the output when the second direction is not parallel to the first direction. According to this embodiment, the operator can suppress or prevent variations in the adhesion of the pre-welded fiber bundles even when there are differences in thermal conductivity due to differences in the direction of fiber bundle extension between the lower layer and the upper layer.

[0075] (8) In the heating width determination method described in any of the above embodiments (1) to (7), the preparation step includes a step of preparing tacking force information relating to the relationship between the heating temperature when heating the fiber bundle to temporarily weld it to the laminated surface and the tacking force which is the force that peels the fiber bundle temporarily welded at the heating temperature away from the laminated surface. The determination step further includes a step of using the tacking force information to determine the target temperature such that the tacking force is within a predetermined range. According to this embodiment, the operator can set manufacturing conditions based on the tacking force that allow for the rearrangement of the temporarily welded fiber bundle while suppressing or preventing the fiber bundle from falling off the laminate.

[0076] (9) A fiber bundle pre-welding method comprising: a heating width determination method according to any of the above embodiments (1) to (8); and a pre-welding step of placing the fiber bundle on the laminated surface, pressing the fiber bundle toward the laminated surface with a predetermined pressing force, and heating the heating region of the fiber bundle placed on the laminated surface having the width determined in the determination step to the target temperature to pre-weld the fiber bundle, wherein the preparation step includes a step of preparing pressing force information relating to the relationship between the tacking force and the pressing force. The determination step includes a step of determining the target temperature using the prepared pressing force information. According to this embodiment, the operator can set manufacturing conditions that allow for the rearrangement of the pre-welded fiber bundle while suppressing or preventing the fiber bundle from falling off the laminate, based on the tacking force and the pressing force that further affects the tacking force.

[0077] 10...Fiber bundle, 30...Supply device, 40...Articulated robot, 50...Substrate, 52...Lamination surface, 60...Placement head, 62...Introduction roller, 64...Feeding mechanism, 66...Cutting device, 67...Guide roller, 68...Pressing roller, 70...Irradiation device, 80...Controller, 82...CPU, 84...Storage device, 86...Communication unit, 90...Server, 100...Fiber bundle placement device, 642...Driven roller, 644...Drive roller, 646...Drive motor, 662...Fixing device, 664...Cutter, 842...Welding temperature information, 844...Temperature drop information, 846...Shape information, 848...Placement direction information, 850...Tacking force information, 852...Pressing force information, CP...Center, E1...One end, E2...Other end, LR...Irradiation area, S1, S2...Tacking force, T1...Target temperature, TH...Welding temperature, WT...Irradiation width

Claims

1. A heating width determination method for determining the width of a heating region of a fiber bundle when a strip-shaped fiber bundle impregnated with resin is laid out on a laminated surface, comprising: a preparation step of preparing welding temperature information relating to the welding temperature at which a first fiber bundle and a second fiber bundle adjacent to the first fiber bundle are welded together, and temperature drop information relating to the relationship between the distance from the heating position when the fiber bundle is heated at a predetermined target temperature and the degree of temperature drop of the fiber bundle according to the distance; and a determination step of using the prepared welding temperature information and temperature drop information to determine the width of the heating region of the fiber bundle that is heated to the target temperature, such that the first fiber bundle and the second fiber bundle do not weld together when the first fiber bundle and the second fiber bundle are heated side by side in the width direction.

2. A method for determining the heating width according to claim 1, wherein the determination step includes: calculating the temperature of the fiber bundle outside the heating region in the width direction using the degree of temperature decrease of the prepared fiber bundle; and comparing the calculated temperature of the fiber bundle outside the width direction with the welding temperature to determine the width of the heating region such that the temperature of the contact portion between the first fiber bundle and the second fiber bundle outside the width direction is less than the welding temperature.

3. A method for pre-welding a fiber bundle, comprising: a heating width determination method according to claim 1 or claim 2; and a pre-welding step of placing the fiber bundle on the laminated surface, and heating the heating region having the width determined in the determination step to the target temperature to pre-weld the fiber bundle, wherein the pre-welding step is a step of heating the heating region using a device capable of adjusting the width of the heating region.

4. A heating width determination method according to any one of claims 1 to 3, wherein the preparation step further includes a step of preparing shape information relating to the shape of the laminated surface, and the determination step further includes a step of determining the width of the heating region using the prepared shape information.

5. A heating width determination method according to claim 4, wherein the shape information includes information on whether or not the laminated surface is flat, and the determination step includes a step of determining the width of the heating region using the prepared shape information such that the width of the heating region when the laminated surface is not flat is greater than the width of the heating region when the laminated surface is flat.

6. A fiber bundle pre-welding method comprising: a heating width determination method according to any one of claims 1 to 5; and a pre-welding step of placing the fiber bundle on the laminated surface, heating the heating region having the width determined in the determination step to the target temperature, thereby pre-welding the fiber bundle, further comprising: arranging the fiber bundle on the laminated surface so that the fiber bundle extends in a first direction to form a first layer; and arranging the fiber bundle on the first layer so that the fiber bundle extends in a second direction to form a second layer, wherein the pre-welding step is a step of heating the heating region using a device capable of adjusting the output when heating the heating region; the preparation step further comprises a step of preparing arrangement direction information relating to the arrangement direction of the fiber bundle, including the first and second directions; and the determination step determines the output using the prepared arrangement direction information.

7. A method for pre-welding a fiber bundle according to claim 6, wherein the determination step includes a step of determining the output such that the output when the second direction is substantially parallel to the first direction is lower than the output when the second direction is not parallel to the first direction.

8. A heating width determination method according to any one of claims 1 to 7, wherein the preparation step includes a step of preparing tacking force information relating to the relationship between the heating temperature at which the fiber bundle is heated and temporarily welded to the laminated surface and the tacking force which is the force that peels the fiber bundle temporarily welded at the heating temperature away from the laminated surface, and the determination step further includes a step of determining the target temperature using the tacking force information so that the tacking force is within a predetermined range.

9. A method for pre-welding a fiber bundle, comprising: a heating width determination method according to claim 8; and a pre-welding step of placing the fiber bundle on the laminated surface, pressing the fiber bundle toward the laminated surface with a predetermined pressing force, and heating the heating region of the fiber bundle placed on the laminated surface having the width determined in the determination step to the target temperature to pre-weld the fiber bundle, wherein the preparation step includes a step of preparing pressing force information relating to the relationship between the tacking force and the pressing force, and the determination step includes a step of determining the target temperature using the prepared pressing force information.

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