JP2007185690A - Vehicle body member hemming method, and vehicle body member hemming structure - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a vehicle body member hemming method, and a vehicle body member hemming structure capable of efficiently enhancing the hemming strength and rigidity, and ensuring the electrolytic corrosion resistance while suppressing the deformation caused by the heat input in a coating process when hemming vehicle body members having combination of dissimilar materials. <P>SOLUTION: In the vehicle body member hemming method, a skin 11 and a frame 12 having combination of dissimilar materials are hemmed with each other. The method comprises a step of applying a thermosetting adhesive 13 on at least one of parts facing each other of the skin 11 and the frame 12, a step of returning an edge 11a of the skin 11 so as to hold the thermosetting adhesive 13 between an edge of the frame 12 and itself, and a step of performing the friction stirring and joining of the skin 11 and the frame 12 from the edge 11a side of the skin 11. In the hemming step, the thermosetting adhesive 13 is heated in advance by the remaining heat during the friction stirring and joining, and the skin 11 is temporarily joined with the frame 12. <P>COPYRIGHT: (C)2007,JPO&INPIT

Description

  The present invention relates to a hemming joining method and a hemming joining structure for vehicle body members such as a door, an engine hood, and a trunk lid.

  Generally, when manufacturing body parts such as doors, engine hoods, and trunk lids, the outer panel is combined with an inner panel disposed on the back side thereof, and the edge of the outer panel is folded back so as to sandwich the edge of the inner panel (hemming). Processing), a technique for joining the edge portions (hemming joining) to each other is known.

Conventionally, various techniques have been proposed for hemming bonding.
For example, there is one that fixes a panel by curing a thermosetting adhesive (structural adhesive) applied between edge portions in a baking coating process. This thermosetting adhesive also serves to ensure the rigidity, strength, and corrosion resistance of the vehicle body member. When fixing with the thermosetting adhesive in this way, the outer panel and the inner panel move after the edges are combined and before the thermosetting adhesive is completely cured by the heat of baking. Temporary fixing to prevent is performed. Examples of the temporary fixing method include a method in which a spherical body added to a thermosetting adhesive is bitten during hemming (see Patent Document 1), a spot welding method, a rivet bonding method, a clinch bonding method, and the like.

  In addition, when temporary fixing by spot welding or the like is not performed, there is a type in which a thermosetting adhesive between edge portions is cured in advance using an induction superheater or the like to prevent displacement between panels (Patent Document). 2).

Furthermore, in recent years, a hemming joining method by friction stir welding has also been proposed (for example, see Patent Document 3). Friction stir welding is performed by placing the edge of the overlapped panel on a cradle and pressing a welding tool rotated at high speed. Specifically, when the pin at the tip of the joining tool reaches the upper panel, the panel is heated and softened by friction. When the panel is softened, the pin is gradually inserted, and when it reaches the vicinity of the boundary with the lower panel, the vicinity of the boundary is further heated to cause plastic flow. Thereby, panels are joined.
JP-A-10-258331 (Claim 1, paragraphs 0005 to 0007, FIG. 2) JP-A-2-254070 (Claims (1), FIG. 1) JP 2004-167525 A (Claim 1, FIG. 5)

  By the way, the various hemming joining methods described above are techniques for joining the same kind of materials to each other, and the case of joining different kinds of materials is not mentioned. When the prior art is applied to the joining of a combination of different materials (for example, a combination of a skin material made of aluminum and a frame material made of mild steel), the following problems occur.

  When fixing with a thermosetting adhesive, deformation of the member may occur due to heat input when the thermosetting adhesive is cured due to the difference in linear expansion coefficient of each material. Therefore, for the purpose different from the prevention of misalignment between the panels, it is necessary to temporarily fix before completely curing by heat input in the painting process. However, the above-described method of causing the spherical body to bite has a problem that temporary fixing cannot be sufficiently performed due to a difference in hardness of the material. Also, in spot welding, rivet joining, clinch joining, etc., there are significant restrictions on materials and shapes such as securing the flange width, etc., and there are also problems with the appearance merchandise such as spot dents, rivet punching marks, ruggedness appearance by clinching . In the case of pre-curing with an induction overheat heater or the like, there are problems that the number of steps for only heat-curing increases and the equipment cost for the heating device is increased.

  On the other hand, according to friction stir welding, it can join before the heat input in a coating process. However, in the case of joining different types of materials, it is necessary to apply a sealing agent for preventing electrolytic corrosion, which increases the number of processes. Furthermore, it is preferable that joint strength and rigidity are further increased.

  Accordingly, the present invention provides a vehicle body member capable of efficiently improving the bonding strength and rigidity and ensuring the resistance to electric corrosion while suppressing deformation due to heat input in the painting process in the bonding of vehicle body members made of a combination of different materials. It is an object to provide a hemming bonding method and a hemming bonding structure.

  In order to solve the above-mentioned problem, the invention according to claim 1 is a hemming joining method of a vehicle body member configured by joining a first member made of a combination of different materials and a second member, and the first member and The adhesive application step of applying a thermosetting adhesive to at least one of the opposing parts of the second member, and the thermosetting adhesive sandwiched between the edge of the second member A hemming process step of folding back an edge portion of the first member, and a joining step of friction stir welding the first member and the second member from the edge portion side of the first member. The thermosetting adhesive is preheated by residual heat at the time of friction stir welding, and the first member is temporarily fixed to the second member.

  According to the first aspect of the present invention, when the first member and the second member, which are a combination of different materials, are joined by friction stir welding, the thermosetting adhesive is preheated by the residual heat during the friction stir welding. The first member is temporarily fixed to the second member. By joining and temporarily fixing each member in this way, when the thermosetting adhesive is completely cured in the subsequent baking coating process, deformation caused by the difference in linear expansion coefficient of each member can be prevented. it can. Moreover, since the preheat of the friction stir welding is used for the preheating of the thermosetting adhesive before the baking coating process, a process and a heating device only for the preheating are not necessary, and the cost can be suppressed. Furthermore, in addition to friction stir welding, it can be temporarily fixed and bonded with a thermosetting adhesive, so that the bonding strength and rigidity can be improved efficiently. Thus, the thermosetting adhesive is interposed between the first member and the second member in this manner, thereby exhibiting a sealing function and ensuring electric corrosion resistance. Thereby, it is not necessary to apply a sealing agent again, and man-hours can be reduced. In addition, since the heat input by friction stir welding is smaller than the heat input by welding etc. which melts and joins a member, deformation | transformation of the member itself by heat input can be suppressed to the minimum.

  The invention according to claim 2 is the hemming joining method of the vehicle body member according to claim 1, wherein the thermosetting adhesive and the friction stir welding part are located on the front and back through the second member. To do.

  According to the second aspect of the present invention, the laminated structure of the end edge of the first member, the end edge of the second member, and the inner part of the first member (the part inside the end edge) formed by hemming. 1, the edge of the first member and the edge of the second member are friction stir welded, and the edge of the second member and the inner part of the first member are joined by a thermosetting adhesive. The thermosetting adhesive is sufficiently preheated because it is in a position where it is susceptible to heat input by friction stir welding, and the first member is securely temporarily fixed to the second member. Moreover, since the edge part of the 2nd member pinched | interposed into the 1st member is reliably joined to the 1st member by the front and back, the joining strength can be improved. Furthermore, the electric corrosion resistance between the inner side of the first member and the second member can be ensured.

  The invention according to claim 3 is the body member hemming joining method according to claim 1 or 2, wherein the first member is aluminum or an aluminum alloy, and the second member is iron or an iron alloy. It is characterized by.

  According to the invention of claim 3, aluminum or an aluminum alloy, which is a combination of different materials, and iron or an iron alloy can be easily joined by using a friction stir welding and a thermosetting adhesive in combination. .

  The invention according to claim 4 is a vehicle body member hemming joining structure joined by the body member hemming joining method according to any one of claims 1 to 3, wherein an edge of the first member is provided. In a state where the thermosetting adhesive is folded between the end portion of the second member and the thermosetting adhesive, the thermosetting adhesive and the friction stir welding portion are front and back through the second member. The first member is temporarily fixed to the second member in a state where the thermosetting adhesive is pre-cured.

  According to the invention which concerns on Claim 4, in the laminated structure of the edge part of the 1st member formed by hemming, the edge part of the 2nd member, and the inner side (part inside the edge part) of the 1st member The edge of the first member and the edge of the second member are friction stir welded, and the edge of the second member and the inside of the first member are temporarily fixed with a thermosetting adhesive. Thus, in a laminated structure, the deformation | transformation in a subsequent baking coating process can be effectively suppressed because the front and back of the 2nd member is being fixed to the 1st member.

  According to the hemming joining method and the hemming joining structure of the vehicle body member according to the present invention, it is possible to efficiently improve the joining strength and rigidity and to ensure the electric corrosion resistance while suppressing deformation due to heat input in the painting process. .

Next, embodiments of the present invention will be described in detail with reference to the drawings as appropriate. FIG. 1 is a perspective view showing a door body of a front door for a vehicle.
As shown in FIG. 1, the door body 1 (vehicle body member) is configured by hemming a skin material 11 facing the vehicle outer side and a frame material 12 positioned on the back side (vehicle compartment side). The door body 1 is composed of a combination of different materials. Examples of the combination include a combination of aluminum or an aluminum alloy as the skin material 11 and iron or an iron alloy as the frame material 12. The hemming joining method and the hemming joining structure of the present invention can be applied to various body members such as an engine hood and a trunk lid in addition to the door described in this embodiment.

  FIGS. 2A to 2D are cross-sectional views showing the edge of the door body for explaining the hemming joining process, and FIG. 3 is a side view showing the door body. Hereinafter, the hemming joining method of the door body 1 will be described with reference to FIGS.

  Fig.2 (a) is a figure which shows an adhesive agent application process. As shown in FIG. 2A, before the skin material 11 and the frame material 12 are combined, a thermosetting adhesive 13 is applied to the inner portion 11b of the skin material 11 facing the frame material 12. At this time, as shown in FIG. 3, the thermosetting adhesive 13 is applied so as to surround the entire peripheral portion of the skin material 11. Normally, since the sealing agent is applied after the door body is assembled, it takes time and effort to pre-program the application location so that the place where the sealing agent is required and the unnecessary place are separated, but in this embodiment Since the application location need not be specified, the specific management as described above becomes unnecessary. Examples of the thermosetting adhesive 13 include an epoxy resin adhesive, a polyester resin adhesive, and a phenol resin adhesive.

  FIG. 2B is a diagram showing a hemming process. As shown in FIG. 2B, the edge portion 11a of the skin material 11 is folded back to the frame material 12 side. Specifically, a hemming process is performed in which the edge portion 11a is folded back with the thermosetting adhesive 13 applied in advance between the skin material 11 and the frame material 12 interposed therebetween. As a result, a laminated structure is formed in which the edge portion 11a of the skin material 11, the edge portion 12a of the frame material 12, and the inner portion 11b of the skin material 11 are combined.

  FIGS. 2C and 2D are diagrams illustrating a joining process by friction stir welding. As shown in FIG. 2C, the rotary probe 2 having a threaded pin portion 21 on the tip side is used for friction stir welding. The rotary probe 2 is pressed toward the end edge portion 11a of the skin material 11 while rotating at high speed. Since the end edge portion 11 a is softened by frictional heat generated between the end portion 11 a and the pin portion 21, the rotary probe 2 is thereby inserted until it contacts the end edge portion 12 a of the frame material 12. The frame material 12 is made of iron or an iron alloy having a melting point higher than that of the skin material 11, and is hardly softened by frictional heat.

  Subsequently, in this state, the rotary probe 2 is sent out along the edge portion 11a. Specifically, as shown in FIG. 3, the rotating probe 2 is sent out so as to trace only a plurality of portions A (friction stir welding sites) surrounded by a two-dot chain line in the peripheral portion of the door body 1. The plurality of portions A are joint portions that are necessary and sufficient for temporarily fixing the skin material 11 to the frame material 12, thereby enabling efficient joining.

  Then, as shown in FIG. 2 (d), the edges 11a and 12a of the skin material 11 and the frame material 12 are brought into contact with each other by causing the periphery of the rotary probe 2 to flow plastically by the rotation of the rotary probe 2. Friction stir welding. At this time, the thermosetting adhesive 13 is partially cured (preliminarily cured) in response to the residual heat generated during the friction stir welding (see FIG. 3). In particular, the lower side of the friction stir welded portion A can easily propagate the residual heat, and can promote curing. Thereby, the skin material 11 is temporarily fixed on the front and back surfaces of the frame material 12. That is, the end edge portion 11a of the skin material 11 and the end edge portion 12a of the frame material 12 are friction stir welded, and the end edge portion 12a of the frame material 12 and the inner portion 11b of the skin material 11 are thermosetting adhesive 13. Thus, a hemming joint structure of the door body 1 temporarily fixed is formed. In addition, since the heat input by friction stir welding is smaller than the heat input by welding etc. which melts and joins a member, the deformation | transformation of the skin material 11 and the frame material 12 itself by heat input can be suppressed to the minimum.

  Thus, the door main body 1 to which the skin material 11 and the frame material 12 are temporarily fixed is heat-input in the subsequent baking coating process, so that the thermosetting adhesive 13 is completely cured and completely joined. . At this time, since the skin material 11 is temporarily fixed on the front and back of the frame material 12, even if the skin material 11 and the frame material 12 having different linear expansion coefficients from each other are input heat, mutual thermal expansion is suppressed, Deformation of the door body 1 is prevented.

According to the above, the following effects can be obtained in the present embodiment.
The door body 1 according to the present embodiment has the skin material 11 temporarily fixed on the front and back of the frame material 12, so that when the thermosetting adhesive 13 is completely cured in the subsequent baking coating process, The deformation | transformation which generate | occur | produces by the difference in the linear expansion coefficient of the frame material 12 can be prevented.

  In addition, since the preheating of the thermosetting adhesive 13 before the baking coating process uses the remaining heat at the time of friction stir welding, a process and a heating device only for preheating are not required, and costs can be reduced. . Furthermore, in addition to friction stir welding, the thermosetting adhesive 13 can be temporarily fixed and bonded, so that the bonding strength and rigidity can be improved efficiently.

  In this embodiment, since the thermosetting adhesive 13 is applied to the lower side of the friction stir welding portion A, the residual heat at the time of the friction stir welding is likely to propagate, and the thermosetting adhesive 13 is sufficiently preheated. The skin material 11 can be securely fixed to the frame material 12 securely.

  Thus, in the completed door body 1, the thermosetting adhesive 13 is interposed between the skin material 11 and the frame material 12, thereby exhibiting a sealing function and ensuring electric corrosion resistance. . Thereby, it is not necessary to apply the sealing agent anew, and the man-hour for that amount can be reduced.

  As mentioned above, although this embodiment was described, this invention is not limited to the said embodiment, It can implement with a various form.

  In the present embodiment, the material of the skin material 11 and the frame material 12 is aluminum or aluminum alloy, iron or iron alloy, but these materials can be appropriately changed.

  In the present embodiment, the friction stir welding portion A is partially provided, but the friction stir welding may be performed over the entire periphery of the door body 1.

  In the present embodiment, the thermosetting adhesive 13 is applied to the skin material 11, but even the material applied to the frame material 12 side is applied to both the skin material 11 and the frame material 12. There may be.

It is a perspective view which shows the door main body of the front door for vehicles. (A)-(d) is sectional drawing which shows the edge part of the door main body for demonstrating a hemming joining process. It is a side view which shows a door main body.

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 Door main body 2 Rotating probe 11 Skin material 11a End edge part 11b Inner part 12 Frame material 12a End edge part 13 Thermosetting adhesive A part

Claims (4)

A hemming joining method for a vehicle body member constituted by joining a first member and a second member made of a combination of different materials,
An adhesive application step of applying a thermosetting adhesive to at least one of the opposing portions of the first member and the second member;
A hemming step of folding back the edge of the first member so as to sandwich the thermosetting adhesive between the edge of the second member;
A step of friction stir welding the first member and the second member from the edge side of the first member,
In the joining step, the thermosetting adhesive is preheated by residual heat at the time of friction stir welding, and the first member is temporarily fixed to the second member.   2. The hemming joining method for vehicle body members according to claim 1, wherein the thermosetting adhesive and the friction stir welding portion are located on the front and back sides of the second member.   The hemming joining method for a vehicle body member according to claim 1 or 2, wherein the first member is aluminum or an aluminum alloy, and the second member is iron or an iron alloy. A hemming joint structure for a vehicle body member joined by the hemming joining method for a vehicle body member according to any one of claims 1 to 3,
In a state in which the end portion of the first member is folded back with the end portion of the second member sandwiching the thermosetting adhesive, the thermosetting adhesive and the friction stir welding site are A hemming joint structure for vehicle body members, wherein the first member is temporarily fixed to the second member in a state where the thermosetting adhesive is pre-cured and located on the front and back via a second member.

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