Metal resin composite and method for manufacturing the same

Abstract

To prevent a resin material from unintentionally flowing into a gap between a mold and an extrusion material, when manufacturing a metal resin composite by press molding.SOLUTION: An extrusion material 20 includes: a first side wall 21 that forms an exposed surface 21a where metal is exposed and that, in a housed state where the extrusion material 20 is housed in a housing part 92 of a first mold 91, is to be adjacent to and opposed to a first inner side face 92a of the housing part 92; a second side wall 22 that forms a coating surface 22a to be coated with a resin material 50, and defines a cavity 90a to be filled with the resin material 50 together with a second inner side face 92b of the housing part 92; and a hook part 29 that protrudes from an end part of the first side wall in a mold opening direction and is engaged with the first mold 91 in the housed state.SELECTED DRAWING: Figure 7

Description

[Technical field]

[0001] The present invention relates to a metal-resin composite and a method for producing the same. [Background technology]

[0002] Various structures and manufacturing methods have been proposed for metal-resin composites applied to structural parts such as vehicle frames. For example, in the composite disclosed in Patent Document 1, a thermosetting carbon fiber reinforced plastic (CFRP) is bonded to the surface of an aluminum extrusion material with an adhesive. In the composite disclosed in Patent Document 2, an aluminum plate and CFRP are integrated by hot pressing the CFRP onto the aluminum plate. [Prior art documents] [Patent documents]

[0003] [Patent Document 1] JP 2017-119422 A [Patent Document 2] JP 2020-104411 A Summary of the Invention [Problem to be solved by the invention]

[0004] When applying the hot press exemplified in Patent Document 2 to the manufacture of a composite including an aluminum extrusion, it is considered necessary to prepare a die so as to form a suitable gap between the die and the aluminum extrusion assumed to have a standard dimension, taking into consideration the tolerance of the aluminum extrusion. This allows the aluminum extrusion formed within the tolerance to be properly placed in the die each time a composite is manufactured. On the other hand, the aluminum extrusion is hot extruded as taught in Patent Document 1. Therefore, twisting and bending are likely to occur during extrusion, making it difficult to increase the dimensional accuracy of the aluminum extrusion.

[0005] Considering the low dimensional accuracy of aluminum extrusions, it is necessary to make the gap between the die and the aluminum extrusion significantly larger than the gap between the mating surfaces of the die. If this is the case, the position of the aluminum extrusion will not be stable relative to the die during hot pressing, and there is a risk that the resin will flow unintentionally into the gap.

[0006] An object of the present invention is to prevent resin material from unintentionally flowing into a gap between a die and an extruded material when producing a metal resin composite by press-molding a resin material onto an extruded material. [Means for solving the problem]

[0007] One aspect of the present invention is a method for manufacturing a metal-resin composite body by press-molding a resin material into an extruded metal material, the method comprising the steps of: preparing a mold including a first mold forming a housing portion for housing at least a portion of the extruded material, and a second mold movable in a mold closing direction and a mold opening direction relative to the first mold; housing the extruded material in the housing portion, disposing the resin material in the first mold; moving the second mold in the mold closing direction to form a cavity defined by the extruded material and the mold; and pressurizing the resin material to form the cavity. and filling a cavity with the extruded material into the cavity, wherein the extruded material forms an exposed surface where the metal is exposed, and in a contained state where the extruded material is contained in the containing section, the extruded material has a first side wall that is closely opposed to a first inner surface of the containing section, a covered surface that is covered with the resin material and defines the cavity together with a second inner surface of the containing section in the contained state, and a hook portion that protrudes from an end of the first side wall in the mold opening direction and is engaged with the first mold in the contained state.

[0008] According to the above configuration, when the resin material is pressurized, the molding pressure acts on the extrusion material through the resin material. The hook portion is engaged with the first mold, so that the extrusion material can maintain a position in which the exposed surface of the first side wall is close to the first inner surface of the housing portion. That is, while the resin material is being filled into the cavity, the gap between the first side wall and the first inner surface can be continuously filled. Since the resin material is prevented from solidifying on the exposed surface and the metal is properly exposed on the exposed surface, the work of peeling off the excess resin after demolding can be omitted or greatly simplified. On the other hand, a gap is formed between the coating surface and the second inner surface, and this gap functions as a cavity into which the resin material to be coated on the coating surface is intentionally poured. The resin material is properly solidified on the coating surface, and the second side wall is properly coated with the resin material.

[0009] The first mold may form a groove defined by an end of an outer surface of the hook and constituting a part of the cavity.

[0010] According to the above-mentioned configuration, a thick resin material can be provided around the hook portion, making it difficult for the resin material to peel off from the extruded material.

[0011] The extruded material and the resin material may form a fitting structure at an end of the second side wall in the mold closing direction.

[0012] According to the above configuration, the resin material solidifies in a state where it is fitted with the extruded material at the end portion of the second side wall, and the resin material is less likely to peel off from the extruded material.

[0013] The extrusion material may further have an external connecting wall that connects the ends of the first side wall and the second side wall in the mold opening direction in the stored state, and a protrusion that protrudes toward the covering surface at a corner portion between the external connecting wall and the second side wall.

[0014] According to the above configuration, the resin material is solidified around the protrusions, so that the resin material is less likely to peel off from the extruded material.

[0015] Another aspect of the present invention provides a metal-resin composite body formed by integrating a resin material with a metallic extrusion material by press molding, the extrusion material having a first side wall forming an exposed surface that exposes the metal, a second side wall forming a covered surface that is covered with the resin material, and a hook portion protruding from an end of the exposed surface of the first side wall.

[0016] According to the above configuration, the first side wall of the extrusion material can be attached to a die used for press molding by using the hook portion protruding from the end of the exposed surface. Therefore, the resin material can be prevented from solidifying on the exposed surface where the metal should be exposed, and the resin material can be properly solidified on the coated surface that should be coated with the resin material. A metal-resin composite with high production efficiency can be provided. Effect of the Invention

[0017] According to the present invention, when a metal resin composite is manufactured by press-molding a resin material onto an extruded material, it is possible to prevent the resin material from unintentionally flowing into the gap between the die and the extruded material. [Brief description of the drawings]

[0018] [Figure 1] Side view of an electric car. [Diagram 2] FIG. 1 is a perspective view of a battery case for an automobile as an application example of the metal-resin composite according to the first embodiment. [Diagram 3] 3 is a perspective view of the automobile battery case taken along line III-III in FIG. 2. [Figure 4] 3 is a cross-sectional perspective view showing an extrusion material, a die, and a insert prepared in the production of a metal-resin composite body. FIG. [Diagram 5] FIG. [Figure 6] FIG. 4 is a cross-sectional view showing the extrusion material and the die in a state in which the resin material is placed. [Figure 7] FIG. 4 is a cross-sectional view showing the extrusion material and the die in a state in which the resin material has been hot-pressed. [Figure 8] FIG. 4 is a perspective cross-sectional view showing the extruded material and the mold after the heat pressing is completed. [Figure 9] FIG. 5 is a view equivalent to FIG. 3 of a second embodiment. [Figure 10] FIG. 7 is a view equivalent to FIG. 5 of a second embodiment. [Figure 11] FIG. 7 is a view equivalent to FIG. 6 of a second embodiment. [Figure 12] FIG. 10 is a view equivalent to FIG. 8 of a second embodiment. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0019] Hereinafter, an embodiment will be described with reference to the drawings. The same or corresponding reference numerals are designated by the same reference numerals, and detailed description thereof will be omitted.

[0020] With reference to FIG. 1, automobile 1 is an electric vehicle that runs by driving a motor with power supplied from a battery 2. Automobile 1 is a vehicle that runs on electricity, and may be, for example, an electric vehicle or a plug-in hybrid vehicle. The type of vehicle is not particularly limited, and may be a passenger car, a truck, a work vehicle, or other mobility. In the following, a passenger car type electric vehicle will be described as an example of an electric vehicle.

[0021] The automobile 1 is equipped with a motor and high-voltage equipment (not shown) in a front portion 3 of the vehicle. The automobile 1 also has an automobile battery case 10 that houses a battery 2, covering almost the entire surface under the floor of the passenger compartment 5 in the center portion 4 of the vehicle body.

[0022] In Fig. 1, the front-rear direction (vehicle length direction) of the automobile 1 is indicated as the X direction, and the up-down direction (vehicle height direction) is indicated as the Z direction. The same notation is used in the subsequent figures, and the width direction (vehicle width direction) of the automobile 1 is indicated as the Y direction in Fig. 2 and subsequent figures.

[0023] 2, the battery case 10 includes a frame 11 in which a plurality of extrusion members 20, 30 are arranged in a frame shape, and a resin material 50 molded integrally with the frame 11.

[0024] The battery case 10 is one of the suitable application examples of the metal-resin composite 100 according to the embodiment. The metal-resin composite 100 is formed by integrating a resin material 50 with metal extrusions 20, 30 by press molding. The metal material of the extrusions 20, 30 is not particularly limited. Light alloys such as aluminum alloys and magnesium alloys are suitable examples of metal materials, and contribute to achieving both weight reduction and high rigidity of structural parts. Unless otherwise specified below, the extrusions 20, 30 are made of aluminum alloys.

[0025] Although detailed illustration is omitted, the extrusion material 20 is obtained by heating and compressing a billet-shaped metal material within the main body of an extrusion molding machine, and extruding it from a die attached to the main body. After being extruded from the die, required processes such as cooling, drawing, and cutting are performed. The cross section of the extrusion material 20 is determined by the shape of the die, so it is uniform in its extension direction (extrusion direction). However, twists and bends occur due to hot forming. Each element of the extrusion material 20 extends in the extension direction and is seamlessly integrated with one another. The same is true for the extrusion material 30.

[0026] The resin material 50 is obtained by press-molding a compound in a manufacturing apparatus 9 (see FIG. 6) for the metal-resin composite 100. The compound may be a sheet-shaped SMC (Sheet Molding Compound) or a bulk-shaped BMC (Bulk Molding Compound). The SMC or BMC is realized by fiber-reinforced plastic (FRP) in which a matrix resin is impregnated with fibers. The matrix resin contains a thermosetting resin such as unsaturated polyester as a main component, and additives are mixed into the main component. The additives include, for example, a mold release agent. The fibers are, for example, glass fibers or carbon fibers, cut short and oriented in random directions in the compound. However, the resin material 50 is not limited to a thermosetting resin, and may be a thermoplastic resin. In the following, the resin material 50 is made of SMC as a mere example.

[0027] As an example, the frame 11 is a rectangular frame in a plan view. The frame 11 includes a pair of side members 12, 13, a front member 14, a rear member 15, and multiple cross members 16. The pair of side members 12, 13 extend in the vehicle length direction. The front member 14 connects the front ends of the pair of side members 12, 13 to each other in the vehicle width direction. The rear member 15 connects the rear ends of the pair of side members 12, 13 to each other in the vehicle width direction. The multiple cross members 16 are disposed at intervals between the front member 14 and the rear member 15, and connect the pair of side members 12, 13 to each other in the vehicle width direction.

[0028] In this embodiment, the pair of side members 12, 13, the front member 14, and the rear member 15 are made of extruded material 20. The cross member 16 is made of an extruded material 30. The extension direction of each member constituting the frame 11 corresponds to the extrusion direction during molding of the extruded material constituting that member. The extruded material 20 and the extruded material 30 have cross-sectional shapes different from each other.

[0029] Of the pair of side members 12, 13, the front member 14, and the rear member 15, the ends of two adjacent members are cut at 45 degrees (so-called miter cuts) and butt together. Both end faces of each cross member abut or are close to the inner faces of the pair of side members 12, 13, respectively.

[0030] The multiple extrusion materials (i.e., the multiple members constituting the frame 11) are connected to each other via the resin material 50. However, among the pairs of two adjacent members, there may be a pair in which the two members are welded to each other at the butt joint, or a pair in which the two members are fastened to each other via a bracket. In other words, among the pairs of two adjacent members, there are quite a few pairs that are not connected to each other by welding or fastening. By eliminating welding and fastening as much as possible, the number of steps in manufacturing the battery case 10 can be reduced.

[0031] The resin material 50 has a bottom wall 51, a surrounding wall 52, and a flange wall 53. The bottom wall 51 is disposed below the frame 11 and is embedded in the lower surface of the frame 11. The lower ends of the pair of side members 12, 13, the front member 14, the rear member 15, and the multiple cross members 16 are connected to each other via the bottom wall 51. The surrounding wall 52 is disposed circumferentially on the horizontal outer side of the frame 11 and is embedded in the outer surface of the frame 11. The lower end of the surrounding wall 52 is continuous with the bottom wall 51. Adjacent two of the pair of side members 12, 13, the front member 14, and the rear member 15 are also connected to each other via the surrounding wall 52. The flange wall 53 extends horizontally outward from the surrounding wall 52.

[0032] A metal joint member 41 having a joint structure with another member (for example, a body frame such as a side sill) is embedded in the flange wall 53. The resin material 50 has a plurality of ridges 54 protruding upward from the bottom wall 51. One ridge 54 extends in the vehicle body width direction within one region formed between two adjacent members of the front member 14, the plurality of cross members 16, and the rear member 15. A metal joint member 42 having a joint structure with the battery 2 (see FIG. 1) is embedded in the ridges 54. The joint member 41 is, for example, a sleeve, and the joint member 42 is, for example, a metal nut.

[0033] 3, the extrusion 20 has a generally rectangular cross section. The extrusion 30 is similar. The extrusion 20 has a first side wall 21, a second side wall 22, a first external connecting wall 23, a second external connecting wall 24, and one or more internal connecting walls 25a, 25b. The extrusion 30 has a first side wall 31, a second side wall 32, a first external connecting wall 33, a second external connecting wall 34, one or more internal connecting walls 35a, 35b, and a pair of extended side walls 36a, 36b.

[0034] In this embodiment, the positions of the extrusion materials 20, 30 and the resin material 50 are upside down during use of the battery case 10 and during manufacture of the battery case 10. During use of the battery case 10, the first external connection walls 23, 33 are positioned on the lower side in the vehicle height direction. A bottom wall 51 of the resin material 50 is embedded in the outer surfaces of the first external connection walls 23, 33 as the lower surface of the frame 11. The second external connection walls 24, 34 are positioned on the upper side in the vehicle height direction.

[0035] During use of the metal-resin composite 100 as the battery case 10, the first outer connection walls 23, 33 are bottom walls of the extrusion materials 20, 30, and the second outer connection walls 24, 34 are top walls of the extrusion materials 20, 30. Here, with reference to Fig. 3, the configuration of the extrusion materials 20, 30 will be described according to the posture of the battery case 10 during use.

[0036] The first side wall 21 of the extrusion material 20 extends upward from an edge on one width direction side of the first outer connecting wall 23. The second side wall 22 of the extrusion material 20 extends upward from an edge on the other width direction side of the first outer connecting wall 23.

[0037] The width direction of the first external connection wall 23 corresponds to the width direction of the extruded material 20. The width direction of the extruded material 20 is a direction perpendicular to both the extrusion direction and the height direction of the extruded material 20. When the extruded material 20 constitutes the side members 12, 13, the width direction of the extruded material 20 corresponds to the vehicle width direction. When the extruded material 20 constitutes the front member 14 or the rear member 15, the width direction of the extruded material 20 corresponds to the vehicle length direction. One width direction side of the first external connection wall 23 corresponds to the horizontal inner side of the battery case 10, and the other width direction side corresponds to the horizontal outer side of the battery case 10.

[0038] The outer surface of the first side wall 21 constitutes the horizontal inner surface of the frame 11. The resin material 50 is not embedded or covered in the inner surface of the frame 11 (the outer surface of the first side wall 21 of the extrusion material 20). The outer surface of the second side wall 22 constitutes the horizontal outer surface of the frame 11. The resin material 50 is embedded in the outer surface of the frame 11. The outer surface of the first side wall 21 is not covered with the resin material 50, and therefore is an "exposed surface 21a" where the aluminum alloy as the material of the extrusion material 20 should be exposed purely at least immediately after demolding. The outer surface of the second side wall 22 is a "covered surface 22a" covered with the resin material 50 and in which the peripheral wall 52 is embedded. Furthermore, the outer surface 23a of the first external connection wall 23 is also covered with the resin material 50 and is a "covered surface" in which the bottom wall 51 is embedded.

[0039] The second outer connecting wall 24 of the extrusion material 20 connects the upper ends of the first side wall 21 and the second side wall 22 to each other in the width direction of the extrusion material 20. In this embodiment, the extrusion material 20 has two inner connecting walls 25a, 25b. The two inner connecting walls 25a, 25b are arranged at an interval in the vertical direction in a hollow space surrounded by the first side wall 21, the second side wall 22, the first outer connecting wall 23, and the second outer connecting wall 24. The inner connecting walls 25a, 25b connect the inner surfaces of the first side wall 21 and the second side wall 22 to each other in the width direction of the extrusion material 20.

[0040] The extrusion material 30 also has two inner connection walls 35a, 35b. The first side wall 31, the second side wall 32, the first outer connection wall 33, the second outer connection wall 34, and the two inner connection walls 35a, 35b of the extrusion material 30 are the same as those of the extrusion material 20. The extrusion material 30 is disposed inside a case surrounded by a pair of side members 12, 13, a front member 14, and a rear member 15. The outer surface of the first side wall 31 and the outer surface of the second side wall 32 are both "exposed surfaces" in which the surrounding wall 52 is not buried. The pair of extended side walls 36a, 36b extend from the first side wall 31 and the second side wall 32, respectively, and protrude downward relative to the first outer connection wall 33. The resin material 50 is buried in the area surrounded by the pair of extended side walls 36a, 36b and the first outer connection wall 33. This increases the bonding strength between the resin material 50 and the extrusion material 30. The outer surface of the first outer connecting wall 33 and the inner surfaces of the pair of extended side walls 36a, 36b are covered with a resin material 50, and are "covered surfaces" in which the bottom wall 51 is embedded.

[0041] 4, in a manufacturing method of a metal resin composite 100 as a battery case 10, a resin material 50 is integrated with extrusion materials 20, 30 by press molding using a die 90. The up-down direction corresponds to the die opening and closing direction of the die 90. In a manufacturing device 9 for the metal resin composite 100, the die opening direction is upward and the die closing direction is downward. The extrusion material 20 is placed in a position relative to the manufacturing device 9 such that the first external connection wall 23 is located upward and the second external connection wall 24 is located downward. The same is true for the extrusion material 30.

[0042] During manufacture of the metal resin composite 100 as the battery case 10, the first outer connection walls 23, 33 are the top walls of the extrusion materials 20, 30, and the second outer connection walls 24, 34 are the bottom walls of the extrusion materials 20, 30, as opposed to during use. Here, with reference to Fig. 4, the extrusion materials 20, 30 and other configurations will be described according to the posture during manufacture of the metal resin composite 100.

[0043] The manufacturing device 9 mainly includes a mold 90, a drive unit 9a, and a heating unit 9b. The mold 90 includes a first mold 91 and a second mold 99 (see FIG. 6). The first mold 91 is configured as a fixed mold, a lower mold, or a die. The second mold 99 is configured as a movable mold, an upper mold, or a punch. The second mold 99 is driven by the drive unit 9a and is movable in a mold closing direction and a mold opening direction relative to the first mold 91.

[0044] The first die 91 forms a receiving portion 92 that receives at least a portion of the extrusion material 20 and a receiving portion 93 that receives at least a portion of the extrusion material 30 .

[0045] The first mold 91 has a base 94 and a shoulder 95. The upper surface of the base 94 forms a horizontal lower molding surface 94a. The shoulder 95 protrudes upward from the periphery of the base 94, and the inner surface of the shoulder 95 extends upward from the lower molding surface 94a.

[0046] Although detailed illustration is omitted, the inner surface of the shoulder 95, in a cross section perpendicular to the mold opening / closing direction, has the same shape as the combination of the bottom wall 51 and the flange wall 53 of the finished metal-resin composite body 100 in a plan view. In this example, as can be seen from FIG. 2, the shape of the combination in a plan view is rectangular, so the shoulder 95 has a rectangular window frame shape in a plan view. The lower part of the inner surface of the shoulder 95 forms a vertical side molding surface 95a. The shape of the side molding surface 95a is transferred as the peripheral surface of the flange wall 53. The upper part of the inner surface of the shoulder 95 forms a lower mating surface 95b.

[0047] The accommodation portion 92 and the accommodation portion 93 are recessed in the lower molding surface 94a. The accommodation portion 92 has an inner surface with a U-shaped cross section and is configured as a groove opened to the lower molding surface 94a. The inner surface of the accommodation portion 92 includes a pair of first inner side surface 92a and second inner side surface 92b extending downwardly in continuity with the lower molding surface 94a, and an inner bottom surface 92c connecting the lower ends of the first inner side surface 92a and the second inner side surface 92b. The accommodation portion 93 is similar to this. The inner surface of the accommodation portion 93 includes a pair of inner sides 93a, 93b and an inner bottom surface 93c. A groove 94b is formed at the upper edge of one side of the accommodation portion 92 in the width direction. A slit 94d is formed in the base 94 by recessing the inner bottom surface of this groove 94b in the mold opening direction.

[0048] Hereinafter, the configuration and operation of the manufacturing apparatus 9 will be described along the steps of the manufacturing method of the metal resin composite body 100. When manufacturing the metal resin composite body 100, first, a die 90 is prepared. Next, the extrusion materials 20 and 30 are accommodated in the accommodation portions 92 and 93 of the prepared first die 91.

[0049] Regarding preparation of the mold 90, the second mold 99 is positioned at a predetermined retreat position away from the first mold 91 in the mold opening direction.

[0050] Regarding the accommodation of the extrusion material 30 in the accommodation section 93, detailed illustration is omitted, but referring to FIG. 4, the extrusion material 30 is inserted from above into the accommodation section 93 with the pair of extended side walls 36a, 36b protruding upward relative to the first external connection wall 33. The second external connection wall 34 abuts against the inner bottom surface 93c of the accommodation section 93, the first side wall 31 is close to the inner surface 93a, and the second side wall 32 is close to the inner surface 93b. A pair of protrusions provided at the tip of each extended side wall 36a, 36b are in close contact with the pair of inner surfaces 93a, 93b, respectively. Note that the cross-sectional shape of the extrusion material 30 is line-symmetrical with respect to a center line passing through the center in the width direction in the up-down direction, so the first side wall 31 may be close to and opposed to the inner surface 93b, and the second side wall 32 may be close to and opposed to the inner surface 93a.

[0051] 4, the extrusion material 20 is inserted into the accommodation portion 92 from above with the first outer connection wall 23 facing upward. The second outer connection wall 34 abuts against the inner bottom surface 92c of the accommodation portion 92, the first side wall 21 is adjacent to the first inner surface 92a, and the second side wall 22 is adjacent to the second inner surface 92b.

[0052] The shape of the extrusion material 20 will now be described in more detail with reference to Figures 4 and 5. Note that the up-down direction on the paper in both Figures 4 and 5 coincides with the up-down direction during manufacturing, and the first outer connection wall 23 faces upward.

[0053] In this embodiment, as a mere example, the first outer connection wall 23, the second outer connection wall 24, and the inner connection walls 25a and 25b are parallel to each other. The first side wall 21 and the second side wall 22 are perpendicular to the first outer connection wall 23 and parallel to each other. However, these walls may have any shape that does not affect demolding after molding, and are not necessarily limited to being parallel or perpendicular.

[0054] A hook portion 29 is provided at the end portion of the first side wall 21 in the mold opening direction, in other words, at the corner portion between the first external connection wall 23 and the first side wall 21. The hook portion 29 protrudes from the end portion of the first side wall 21. The hook portion 29 has an L-shaped cross section and has a protruding portion 29a and a bent portion 29b. The protruding portion 29a protrudes from the end portion of the exposed surface 21a of the first side wall 21 toward one side in the width direction. In other words, it is formed by extending the first external connection wall 23 toward one side in the width direction relative to the first side wall 21. The bent portion 29b protrudes from the tip of the protruding portion 29a in the mold closing direction so as to be bent.

[0055] The end of the second side wall 22 in the mold closing direction, in other words, the corner between the second external connection wall 24 and the second side wall 22, is given a complex uneven shape. The second external connection wall 24 is recessed upward on the other side in the width direction. The second external connection wall 24 has a base portion 24a on one side in the width direction, an offset portion 24c offset to the mold opening direction side (upward during manufacturing) from the base portion 24a on the other side in the width direction, and a step portion 24b connecting the base portion 24a and the offset portion 24c in the mold opening and closing direction (up and down direction) at the center in the width direction. The lower end of the second side wall 22 protrudes toward the mold closing direction side (downward during manufacturing) more than the offset portion 24c. As a result, the lower end of the second side wall 22, the offset portion 24c, and the step portion 24b form an uneven shape. The lower end of the second side wall 22 is located on the mold opening direction side (upper side during manufacturing) relative to the outer surface of the base portion 24a, and does not interfere with the inner surface of the accommodation portion 92.

[0056] 6, when the extrusion material 20 is inserted into the accommodation portion 92, the bent portion 29b of the hook portion 29 is inserted into the slit 94d from above. The lower surface or inner surface (i.e., the surface on the mold closing direction side) of the protruding portion 29a of the hook portion 29 is supported by the inner bottom surface of the groove 94b. The hook portion 29 is disposed on the other widthwise side of the groove 94b. The tip surface of the hook portion 29 faces into the groove 94b. The remaining portion of the groove 94b that is not filled with the hook portion 29 has the other widthwise side defined by the end surface of the hook portion 29, while the upper side (the mold opening direction side) is still open.

[0057] A protruding rib 92d protrudes in the mold opening direction (upward during production) from an inner bottom surface 92c of the accommodation portion 92. When the extrusion material 20 is accommodated in the accommodation portion 92, the base portion 24a abuts against the inner bottom surface 92c on the first inner surface 92a side relative to the protruding rib 92d, and the step portion 24b is engaged with the protruding rib 92d.

[0058] An outer surface (exposed surface 21a) of the first side wall 21 is in surface contact with or closely faces a first inner surface 92a of the accommodation portion 92 formed by the base 94. The first inner surface 92a extends vertically from an inner bottom surface 92c, that is, in the mold opening / closing direction.

[0059] The outer surface (covering surface 22a) of the second side wall 22 is disposed at a distance from the second inner surface 92b. The second inner surface 92b extends in the mold opening / closing direction in the same manner as the first inner surface 92a.

[0060] The step portion 24b is higher than the protruding strip 92d. That is, the offset portion 24c of the second outer connection wall 24 is located on the mold opening direction side of the protruding end surface of the protruding strip 92d. The lower end of the second side wall 22 is located near the second inner surface 92b with respect to the protruding strip 92d while being separated from the second inner surface 92b and forming a space together with the second inner surface 92b. The lower end of the second side wall 22 faces a part of the inner bottom surface 92c that is closer to the second inner surface 92b than the protruding strip 92d in the mold opening and closing direction. In this way, the space between the outer surface (coating surface 22a) of the second side wall 22 and the second inner surface 92b communicates with the clearance between the lower end of the second side wall 22 and the inner bottom surface 92c and the clearance between the offset portion 24c and the protruding strip 92d, and forms a maze-like space as a whole.

[0061] The upper edge of the second inner surface 92b is lower than the upper edge of the first inner surface 92a. The end of the second inner surface 92b in the mold opening direction is continuous with the outer peripheral edge of the lower molding surface 94a of the base 94 via a tapered surface 94c. A cylindrical insert 97 is erected on the outer peripheral edge of the lower molding surface 94a. A metal nut is fitted on the outside of the cylindrical insert 97 as the joining member 41 (the nut may be threaded or not). Although not shown in detail, a cylindrical insert and a joining member 42 are similarly installed on the lower molding surface 94a on the further left side of the cutting line on the left side of the paper surface in FIG. 6.

[0062] In this manner, the second inner surface 92b is relatively low, and the tapered surface 94c is provided. As a result, the space between the outer surface (covered surface 22a) of the second side wall 22 and the second inner surface 92b is widely opened in the mold opening direction via a clearance between the tapered surface 94c and the extrusion material 20.

[0063] Next, the mold 90 is preheated by the heating unit 9b, and the temperature of the mold 90 is raised to a predetermined temperature. Then, a compound of the resin material 50 is placed on the first mold 91. The extrusion material 20 and the joining member 41 (and, although not shown in detail, the extrusion material 30 and the joining member 42 (see FIG. 2)) are placed on the first mold 91. The compound covers these from above.

[0064] The compound is, for example, SMC. A plurality of sheet-like compounds are laminated in the space surrounded by the shoulder portion 95. In this embodiment, a larger amount of resin is required around the housing portion 92 to mold the peripheral wall 52 and the flange wall 53 of the resin material 50, as compared with, for example, the central region of the lower molding surface 94a. Therefore, the number of layers of compound laminated around the housing portion 92 is larger than other portions.

[0065] The above-mentioned cylindrical insert 97, the extrusion members 20 and 30, the joining members 41 and 42, and the compound of the resin material 50 may be manually installed. The manufacturing apparatus 9 may include a manipulator that performs a part or all of such installation work.

[0066] Next, referring to FIG. 7, the driving unit 9a moves the second mold 99 from the retreated position to the bottom dead center in the mold closing direction. The second mold 99 is a rectangular parallelepiped, as a mere example. The lower surface of the second mold 99 constitutes an upper molding surface 99a that faces the lower molding surface 94a of the first mold 91 in the mold opening / closing direction. The side surface of the second mold 99 forms an upper mating surface 99b that extends upward from the periphery of the upper molding surface 99a. In a cross section perpendicular to the mold opening / closing direction, the upper mating surface 99b is similar to the inner surface of the shoulder portion 95 of the first mold 91, but is very slightly smaller than this.

[0067] During the process of the second mold 99 moving downward, the second mold 99 is fitted into the shoulder portion 95, and the upper mating surface 99b closely faces the lower mating surface 95b with a small mold gap. The second mold 99 is guided by the shoulder portion 95 and slides in the mold closing direction. The upper molding surface 99a of the second mold 99 comes into contact with the surface layer of the compound of the resin material 50 before the second mold 99 reaches the bottom dead center. FIG. 6 shows this state. The second mold 99 is driven by the drive unit 9a to move further in the mold closing direction, and the compound of the resin material 50 is pressed in the mold closing direction. The compound is softened by the heat of the mold 90 and flows when pressed by the molding pressure applied from the second mold 99.

[0068] 7 shows a bottom dead center state where the second mold 99 is located at the bottom dead center. In the bottom dead center state, the upper molding surface 99a and the lower molding surface 94a are separated in the mold opening / closing direction. The lower mating surface 95b is a portion of the inner surface of the shoulder portion 95 that is closer to the mold opening direction than the upper molding surface 99a. The side molding surface 95a is a portion of the inner surface of the shoulder portion 95 that is closer to the mold closing direction than the upper molding surface 99a. The lower molding surface 94a, the side molding surface 95a, and the upper molding surface 99a define a cavity 90a. The cavity 90a is a space intended to be filled with the resin material 50.

[0069] The space between the second side wall 22 and the second inner surface 92b is intended to be filled with the resin material 50, and therefore constitutes a part of the cavity 90a. The resin material 50 filled in this space covers the outer surface (covered surface 22a) of the second side wall 22, and constitutes the surrounding wall 52 (see FIG. 2). On the other hand, the space between the first side wall 21 and the first inner surface 92a is not intended to be filled with the resin material 50. The outer surface (exposed surface 21a) of the first side wall 21 is not intended to be covered with the resin material 50, and it is expected that the aluminum alloy is exposed in its pure form at least immediately after demolding. In addition, the mold gap between the lower mating surface 95b and the upper mating surface 99b is also not intended to be filled with the resin material 50.

[0070] As the resin material 50 is pressed in the mold closing direction, the molding pressure of the second mold 99 is applied onto the outer surface 23 a of the first outer connection wall 23 via the resin material 50 .

[0071] In this embodiment, the hook portion 29 is engaged with the first mold 91. This allows the extrusion material 20 to maintain an upright state in the mold opening / closing direction in the housing portion 92, and prevents the extrusion material 20 from falling toward the second inner surface 92b. When the extrusion material 20 stands up in the housing portion 92, an appropriately wide space is secured between the extrusion material 20 and the tapered surface 94c. This makes it easier for the resin material 50 to flow from an area above the lower molding surface 94a into the space between the second side wall 22 and the second inner surface 92b. Since the flow resistance of this filling path is reduced, it is also possible to prevent the resin material 50 from flowing into small gaps (e.g., mold gaps) that are not intended to be filled with resin.

[0072] The resin material 50 flows in the space between the second side wall 22 and the second inner surface 92b in the mold closing direction. As a result, the molding pressure of the second mold 99 is applied to the outer surface (covered surface 22a) of the second side wall 22 toward one side in the width direction through the resin material 50. As a result, the extrusion material 20 is pressed toward the first inner surface 92a.

[0073] In this manner, by pressing the second side wall 22 toward the first inner surface 92a, the outer surface (exposed surface 21a) of the first side wall 21 is brought into close contact with the first inner surface 92a of the storage portion 92. The space between the first side wall 21 and the first inner surface 92a is filled. Unintended inflow of the resin material 50 can be suppressed, and the exposed surface 21a of the first side wall 21 is not covered with the resin material 50.

[0074] When the resin material 50 flows into the space between the second side wall 22 and the second inner surface 92b, it also fills the space communicating with this space. The resin material 50 covers the periphery of the lower end of the second side wall 22, and also fills the space surrounded by the offset portion 24c and the step portion 24b.

[0075] The groove 94b is open toward the mold opening direction and functions as a part of the cavity 90a, and the resin material 50 is filled into the groove 94b to cover the periphery of the hook portion 29. Furthermore, the resin material 50 is filled around the metal nut serving as the joining member 41. That is, the joining member 41 is integrated with the resin material 50.

[0076] While the groove 94b functions as a part of the cavity 90a, the space between the exposed surface 21a and the first inner side surface 92a is not intended for the resin material 50 to flow into. The two can communicate with each other through the space between the hook 29 and the base 94. However, the space is labyrinth-shaped due to the engagement between the hook 29 and the base 94, so that the resin material 50 is difficult to enter through the groove 94b. Moreover, the molding pressure applied to the first outer connection wall 23 presses the hook 29 in the mold closing direction. As a result, the bent portion 29b of the hook 29 is pressed against the inner surface of the slit 94d, and the protruding portion 29a of the hook 29 is pressed against the inner bottom surface of the groove 94b. Therefore, the space between the hook 29 and the base 94 is filled, and the resin material in the groove 94b can be prevented from entering between the exposed surface 21a and the first inner side surface 92a.

[0077] When a predetermined period of time has elapsed with the second mold 99 positioned at the bottom dead center, the resin material 50 hardens. After the resin material 50 hardens, the drive unit 9a moves the second mold 99 in the mold opening direction to the retreated position. As a result, the metal resin composite 100 remains in the first mold 91, as shown in FIG. 8. Then, the metal resin composite 100 is removed from the first mold 91.

[0078] After the metal-resin composite body 100 is released from the mold, the metal-resin composite body 100 may be turned upside down as necessary as shown in FIG. 2 and FIG. 3 for use.

[0079] In the metal resin composite 100 manufactured as described above, the extrusion material 20 has a hook portion 29 protruding from an end of the exposed surface 21a of the first side wall 21. Then, as shown in one example of the manufacturing method, the first side wall 21 of the extrusion material 20 is in close contact with the first inner surface 92a of the accommodation portion 92 by using the hook portion 29, so that the upright posture of the extrusion material 20 can be maintained. This makes it possible to prevent the resin material 50 from solidifying on the exposed surface 21a where the aluminum alloy should be exposed, at least immediately after demolding. Therefore, the work of peeling off the excess resin material after demolding can be omitted or greatly simplified, and the production efficiency of the metal resin composite 100 is improved.

[0080] When the extrusion material 20, 30 is integrally molded with the resin material 50, it is considered desirable to design the housing portion 92, 93 so that the gap between the extrusion material 20, 30 and the inner surface of the housing portion 92, 93 is appropriately large due to the low dimensional accuracy of the extrusion material 20, 30. This gap can cause the excess resin material to be peeled off. In this embodiment, the outer surface of the second side wall 22 functions as a covering surface 22a to which the resin material 50 is intentionally fixed. This makes it easier to properly install the extrusion material 20 in the mold 90, suppresses the occurrence of the peeling operation of the excess resin material 50, and improves the bonding strength between the extrusion materials 20, 30 via the resin material 50. By improving the bonding strength, welding and fastening can be omitted or reduced, and the production efficiency of the metal-resin composite 100 is further improved.

[0081] The first mold 91 has a groove 94b that is defined by the hook portion 29 and forms a part of the cavity 90a. The resin material 50 that flows into the groove 94b solidifies, so that a thick layer of the resin material 50 is provided around the hook portion 29. The resin material 50 is piled up in a bank shape, so that the strength of the metal-resin composite body 100 is improved, and the resin material 50 is also less likely to peel off from the extrusion material 20.

[0082] The extrusion material 20 and the resin material 50 form a fitting structure at the end of the second side wall 22 in the mold closing direction. In this regard, in this embodiment, the extrusion material 20 has a complex uneven shape at the corner portion between the second side wall 22 and the second external connection wall 24. The resin material 50 is filled around the portion forming this uneven shape through the space between the covering surface 22a and the second inner surface 92b. This forms a fitting structure. As a result, the extrusion material 20 and the resin material 50 are crimped together, making it difficult for the resin material 50 to peel off from the extrusion material 20.

[0083] Next, the second embodiment will be described with reference to FIGS. 9 to 12, focusing on the differences from the first embodiment.

[0084] In the extrusion material 20 according to this embodiment, the first external connection wall 23 extends toward the other widthwise side relative to the second side wall 22. Due to this extension, a protrusion 26 that protrudes toward the other widthwise side is provided at the corner portion between the first external connection wall 23 and the second side wall 22. The end face of the protrusion 26 is inclined toward the other widthwise side as it approaches the mold closing direction.

[0085] As in the first embodiment, the upper edge of the second inner surface 92b is relatively low, and a tapered surface 94c is provided. Therefore, in the state where the extrusion material 20 is housed, the protrusion 26 does not interfere with the second inner surface 92b or the lower molding surface 94a. The space between the outer surface (covering surface 22a) of the second side wall 22 and the second inner surface 92b is widely opened in the opening direction through the clearance between the tapered surface 94c and the protrusion 26. When the resin material 50 is pressurized, the resin material 50 covers the periphery of the protrusion 26 in the process of flowing into the space between the second side wall 22 and the second inner surface 92b. When molding pressure is applied to the inclined surface of the protrusion 26, the extrusion material 20 is pushed toward the first inner surface 92a by the action of a wedge. This makes it easier to close the gap between the exposed surface 21a and the first inner surface 92a.

[0086] The resin material 50 solidifies around the projections 26, and the extruded material 20 is crimped and joined to the resin material 50. Therefore, the resin material 50 becomes even more difficult to peel off from the extruded material 20.

[0087] Although the embodiment of the present invention has been described above, the above configuration can be appropriately added to, deleted from, or modified within the scope of the present invention.

[0088] In the above embodiment, the protrusion 26 is formed by extending the first external connection wall 23 to the other widthwise side, and protrudes from the second side wall 22. The protrusion may be formed by extending another wall, or may protrude from another wall. For example, the protrusion may be formed by extending the first side wall 21 or the second side wall 22 in the mold opening direction. The protrusion 26 may be formed by extending the first external connection wall 23 to one widthwise side, and may protrude from the first side wall 21. Conversely, the protrusion may be omitted. The fitting structure may be omitted.

[0089] The metal-resin composite body 100 can also be applied to vehicle structural members other than the battery case 10. The metal-resin composite body 100 can also be applied to structural members used for purposes other than vehicles.

[0090] The present disclosure may include the following aspects. (Aspect 1) A method for manufacturing a metal-resin composite body in which a resin material is integrated with a metal extrusion material by press molding, Preparing a mold including a first mold forming a housing portion that houses at least a portion of the extrusion material, and a second mold movable in a mold closing direction and a mold opening direction relative to the first mold; The extrusion material is accommodated in the accommodation portion, and the resin material is placed in the first mold; moving the second mold in the mold closing direction to form a cavity defined by the extrusion material and the mold, and pressurizing the resin material to fill the cavity; Equipped with The extrusion material is a first side wall that forms an exposed surface on which the metal is exposed and that faces closely to a first inner surface of the housing portion when the extrusion material is housed in the housing portion; a second side wall that forms a covering surface that is covered with the resin material and that, in the accommodated state, defines the cavity together with a second inner surface of the accommodation portion; a hook portion that protrudes from an end portion of the first side wall in the mold opening direction and is engaged with the first mold in the accommodated state; having A method for manufacturing a metal-resin composite. (Aspect 2) The first mold forms a groove defined by an end of an outer surface of the hook and constituting a part of the cavity. A method for producing the metal-resin composite according to aspect 1. (Aspect 3) the extrusion material and the resin material form a fitting structure at an end portion of the second side wall in the mold closing direction. 3. A method for producing a metal-resin composite according to claim 1 or 2. (Aspect 4) The extrusion material is an outer connection wall that connects ends of the first side wall and the second side wall in the mold opening direction in the accommodated state; a protrusion protruding from the covering surface at a corner portion between the outer connection wall and the second side wall; Further comprising A method for producing a metal-resin composite according to any one of aspects 1 to 3. (Aspect 5) A metal-resin composite body formed by integrating a resin material with a metal extrusion material by press molding, The extrusion material is a first sidewall forming an exposed surface that exposes the metal; A second side wall forming a coating surface to be coated with the resin material; a hook portion protruding from an end portion of the exposed surface of the first side wall; having Metal resin composite. [Explanation of symbols]

[0091] 1. Automobiles 2 Battery 3. Front of vehicle 4. Center of the vehicle 5 Cabin 9 Manufacturing equipment 9a Drive unit 9b Heating section 10 Battery case 11 Frame 12,13 Side member 14 Front member 15 Rear member 16 Cross member 20 Extrusion Materials 21 First side wall 21a Exposed surface 22 Second side wall 22a Covered surface 23 First external connecting wall 23a Outer surface 24 Second external connecting wall 24a Base 24b Step 24c offset section 25a, 25b Internal connecting wall 26 Protrusion 29 Hook part 29a Protrusion 29b Bend part 30 Extrusion Materials 31 First side wall 32 Second side wall 33 First external connecting wall 34 Second external connecting wall 35a, 35b Internal connecting wall 36a,36b Extension side wall 41,42 Joint members 50 Resin material 51 Bottom wall 52 Perimeter Wall 53 Flange wall 54 Ridge 90 Mold 90a cavity 91 First Mold 92 Storage unit 92a 1st inner surface 92b 2nd inner surface 92c Inner bottom surface 92d Convex stripe 93 Storage unit 94 Base 94a Lower molding surface 94b Groove 94c Tapered surface 94d Slit 95 Shoulder 95a Side molding surface 95b Lower mating surface 97 Cylinder nest 99 2nd Mold 99a Upper molding surface 99b Upper mating surface 100 Metal resin composite

Claims

1. A method for manufacturing a metal-resin composite body in which a resin material is integrated with a metal extrusion material by press molding, Preparing a mold including a first mold forming a housing portion that houses at least a portion of the extrusion material, and a second mold movable in a mold closing direction and a mold opening direction relative to the first mold; The extrusion material is accommodated in the accommodation portion, and the resin material is placed in the first mold; moving the second mold in the mold closing direction to form a cavity defined by the extrusion material and the mold, and pressurizing the resin material to fill the cavity; Equipped with The extrusion material is a first side wall that forms an exposed surface on which the metal is exposed and that faces closely to a first inner surface of the housing portion when the extrusion material is housed in the housing portion; a second side wall that forms a covering surface that is covered with the resin material and that, in the accommodated state, defines the cavity together with a second inner side surface of the accommodation portion; a hook portion that protrudes from an end portion of the first side wall in the mold opening direction and is engaged with the first mold in the accommodated state; having A method for manufacturing a metal-resin composite.

2. The first mold forms a groove defined by an end of an outer surface of the hook and constituting a part of the cavity. The method for producing the metal-resin composite body according to claim 1 .

3. the extrusion material and the resin material form a fitting structure at an end portion of the second side wall in the mold closing direction. The method for producing a metal-resin composite body according to claim 1 or 2.

4. The extrusion material is an outer connection wall that connects ends of the first side wall and the second side wall in the mold opening direction in the accommodated state; a protrusion protruding from the covering surface at a corner portion between the outer connection wall and the second side wall; Further comprising The method for producing a metal-resin composite body according to claim 1 or 2.

5. A metal-resin composite body formed by integrating a resin material with a metal extrusion material by press molding, The extrusion material is a first sidewall forming an exposed surface that exposes the metal; a second side wall forming a coating surface to be coated with the resin material; a hook portion protruding from an end portion of the exposed surface of the first side wall; having Metal-resin composite.

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