WO2021200736A1 - Method for manufacturing contact joint structure, contact joint structure, and automotive part - Google Patents

Abstract

A method for manufacturing a contact joint structure according to one embodiment of the present invention includes: passing the shaft of a rivet through a through-hole of a first member, said rivet being equipped with the shaft and a flange provided to a first end section of the shaft in the axial direction; bringing the first member into contact with the flange to secure the first member; passing the shaft of the rivet through a through-hole of a second member so as to overlap the first member and the second member; and deforming a second end section of the shaft in the axial direction to crimp the first member and the second member.

Description

Manufacturing method of joint joint structure, joint joint structure and automobile parts

The present invention relates to a method for manufacturing a joint joint structure, a joint joint structure, and an automobile part.
The present application claims priority based on Japanese Patent Application No. 2020-060157 filed in Japan on March 30, 2020, the contents of which are incorporated herein by reference.

The application of high-strength steel sheets as structural members is being promoted for the purpose of reducing the weight of automobiles and improving collision safety. On the other hand, the spot welded joint made of a high-strength steel plate has a problem that the cross tension strength (CTS) decreases when the tensile strength of the base steel plate exceeds 780 MPa. Further, when the tensile strength of the steel sheet exceeds 1500 MPa, not only the cross tensile strength but also the tensile shear strength (Tensil Shear Strength, TSS) tends to decrease.

If the strength of the spot welded joint is reduced, there is a risk that the welded part will break when the member is deformed due to a collision under extremely severe conditions. Therefore, even if the strength of the steel sheet is improved, the load capacity of the member as a whole may be insufficient. Therefore, there is a demand for a joining method for improving the strength of a joint made of high-strength steel plate.

There is a rivet joint as one of the means to improve the cross tensile strength of the joint. In rivet joining, a through hole is formed in a steel plate, a rivet (fastening member) having a head and a shaft portion is inserted through the through hole, the tip of the shaft portion of the rivet is plastically deformed at room temperature, and the rivet is joined. This is a joining method in which a steel plate is crimped by a head and a plastically deformed part. Not limited to high-strength steel sheets, for example, the following techniques are being studied regarding a method for manufacturing a rivet joint structure.

Patent Document 1 discloses a method of connecting two or more constituent members to each other by a fastener. In this method, each component is provided with a hole and is arranged so that the holes overlap each other to receive the fastener in the hole, and the fastener arranged in the hole is mechanically pressurized and heated. , The fastener is deformed. As a result, the constituent members are joined to each other.

Patent Document 2 discloses a method of energizing and heating a rivet with a head portion and a tip portion sandwiched between a pair of electrodes and pressing the rivet for riveting. In this method, the cross-sectional area is small between the back surface of the head of the rivet and the rivet material, and the shaft portion of the rivet is sufficiently closely filled in the rivet hole, or after that, the back surface of the head and the cover are covered. Riveting is performed by providing a seat portion having a height so as to come into contact with the rivet material.

In Patent Document 3, in a method of fastening a rivet in which a rivet is sandwiched between electrodes and heated by resistance heat through electricity to perform pressure molding, the molded temporal electrode is once separated from the rivet after energization heating, and the tip portion of the rivet is formed. A method of rivet fastening is disclosed.

In Patent Document 4, at least a part of a rivet hole formed through at least two members to be joined is formed as a tapered hole, the rivet is fitted into the rivet hole, and the shaft portion of the rivet is subjected to energization caulking. Disclosed is a member joining method by energizing caulking of a rivet, in which the shaft portion of the rivet and the tapered hole are brought into close contact with each other by heat shrinkage of the rivet after energization caulking. ing. Here, the rivet temperature at the time of energization caulking is said to be 700 to 900 ° C.

Patent Document 5 describes a rivet tightening method in which a plurality of workpieces are joined by using rivets. The rivets inserted through the plurality of workpieces are sandwiched between a pair of electrodes and energized in a pressurized state, and the rivets are energized. A rivet tightening method is disclosed in which the rivet is softened by its own resistance heat generation and the end portion of the rivet is crimped.

In Patent Documents 1 to 5, various forms of riveting are studied. However, in any of Patent Documents 1 to 5, the cross tensile strength and the tensile shear strength of the rivet joint structure are not examined at all, and the configuration for improving them is not examined.

The present inventors have found that the cross tensile strength of a joint (also referred to as a rivet joint) obtained by riveting a high-strength steel plate is significantly higher than that of a spot welded joint. It is considered that this is because the rivet joint in which the steel plates are mechanically joined does not cause embrittlement of the joint portion, so that the CTS of the joint joint made of the high-strength steel plate can be held high.

However, it is not easy to use rivet joining instead of spot welding, for example, in the manufacture of automobile parts. In spot welding, it is necessary to heat and pressurize the steel sheet. A pair of electrodes is used to heat and pressurize the steel sheet. On the other hand, in rivet joining, it is necessary to insert the rivet through the steel plate and then heat and pressurize the rivet. Although the electrodes for spot welding can be used for heating and pressurizing rivets, in order to use the equipment for spot welding as equipment for rivet joining, a mechanism for supplying rivets to the steel sheet is required. Need to add to this equipment. However, the addition of a mechanism to the joining equipment leads to an increase in production cost and further reduces the versatility of the production line. In particular, the addition of a mechanism for the rivet supply device to the final welding line of the vehicle body of an automobile for welding a plurality of vehicle types leads to a decrease in the versatility of the line.

The present inventors considered moving the steel sheet to the joining equipment after inserting the rivet into the through hole of the steel sheet in advance. According to this method, it is not necessary to add a rivet supply mechanism to the joining equipment. However, there were cases where the rivets fell off while the steel plate through which the rivets were inserted was moved to the joining equipment. Therefore, it was considered that the supply of rivets had to be carried out at the joining facility so as not to impair the yield of production. It should be noted that Patent Documents 1 to 5 have not examined a method for reliably and easily supplying rivets as described above.

Due to the above circumstances, a joining method with excellent productivity is required without impairing the advantages of rivet joining.

Japan Special Table 2006-507128 Japanese Patent Application Laid-Open No. 55-27456 Japanese Patent Application Laid-Open No. 53-78486 Japanese Patent Application Laid-Open No. 61-165247 Japanese Patent Application Laid-Open No. 10-205510

The present invention provides a method for manufacturing a joint joint structure capable of providing a structure having excellent productivity and high cross tensile strength, and a joint joint structure and automobile parts having excellent productivity and high cross tensile strength. Is the subject.

(1) In the method for manufacturing a joint joint structure according to one aspect of the present invention, the shaft portion of the rivet including the shaft portion and the flange provided at the first end portion in the axial direction of the shaft portion is first. Passing through the through hole of the member, contacting and fixing the first member with the flange, passing the shaft portion of the rivet through the through hole of the second member, and overlapping the first member and the second member. This includes deforming the second end portion of the shaft portion in the axial direction to crimp the first member and the second member.
(2) In the method for manufacturing a joint joint structure according to (1) above, a flange protrusion is provided on the bearing surface of the flange, and the flange protrusion and the first member are projected welded to form the first member. The member may be brought into contact with the flange and fixed.
(3) In the method for manufacturing a joint joint structure according to (1) above, a shaft protrusion is provided in the radial direction of the shaft, the first member is crimped by the shaft protrusion, and the first member is crimped. It may be fixed in contact with the flange.
(4) In the method for manufacturing a joint structure according to any one of (1) to 3 above, the rivet is sandwiched between a pair of electrodes in the axial direction, the rivet is pressurized in the axial direction, and the rivet is pressed in the axial direction. The second end may be deformed by energizing the pair of electrodes.
(5) In the method for manufacturing a joint structure according to any one of (1) to (4) above, the first member or the second member is a steel plate, and the rivet is a steel material.
(6) In the method for manufacturing a joint structure according to any one of (1) to (5) above, one or more welding methods selected from the group consisting of spot welding, laser welding, and arc welding are used. The first member and the second member and / or the second member may be joined to each other.
(7) In the method for manufacturing a joint structure according to any one of (1) to (6) above, among the first member and the second member, an adhesive layer or a seal layer is formed around the through hole. The adhesive layer or the seal layer may be sandwiched between the first member and the second member.

(8) The joint joint structure according to another aspect of the present invention includes a rivet, a first member, and a second member, and the rivet includes a shaft portion and an axial first end portion of the shaft portion. The shaft portion passes through the through hole of the first member, the shaft portion passes through the through hole of the second member, and the first member is fixed in contact with the flange. Further, the first member and the second member are crimped by the flange of the rivet and the second end portion of the shaft portion in the axial direction.
(9) In the joint joint structure according to (8) above, a flange protrusion is provided on the seat surface of the flange, the flange protrusion and the first member are welded, and the first member is attached to the flange. It may be in contact and fixed.
(10) In the joint joint structure according to (8) above, a shaft protrusion is provided in the radial direction of the shaft, the first member is crimped by the shaft protrusion, and the first member comes into contact with the flange. It may be fixed.
(11) In the joint joint structure according to any one of (8) to (10) above, one or more of the first member or the second member is a steel plate, and the rivet is a steel material. May be good.
(12) In the joint joint structure according to any one of (8) to (11) above, an adhesive layer or a seal layer is provided around the shaft portion, and the first member and the second member are adhered to each other. The layer or the sealing layer may be sandwiched.
(13) In the joint joint structure according to any one of (8) to (12) above, the first member and the second member may be welded to each other.

(14) The automobile part according to another aspect of the present invention includes the joint joint structure according to any one of (8) to (13) above.
(15) The automobile part according to (14) above may be a bumper or a B-pillar.

The present invention can provide a method for manufacturing a joint joint structure capable of providing a structure having excellent productivity and high cross tensile strength, and a joint joint structure and automobile parts having excellent productivity and high cross tensile strength.

It is a schematic cross-sectional view for demonstrating the manufacturing method of the joint joint structure which concerns on 1st Embodiment, and is the figure which shows the rivet and the 1st member. It is a schematic cross-sectional view for demonstrating the manufacturing method of the joint joint structure which concerns on 1st Embodiment, and is the figure which shows the state which sandwiched a rivet and a 1st member by a 1st electrode. It is a schematic cross-sectional view for demonstrating the manufacturing method of the joint joint structure which concerns on 1st Embodiment, and is the figure which shows the state which superposed the 1st member which fixed the flange, and 2nd member. It is a schematic cross-sectional view for demonstrating the manufacturing method of the joint joint structure which concerns on 1st Embodiment, and is the figure which shows the state which sandwiched the rivet with a pair of 2nd electrodes in the axial direction. It is a schematic cross-sectional view for demonstrating the manufacturing method of the joint joint structure which concerns on 1st Embodiment, and is the figure which shows the state which the joining is completed. It is a schematic plan view for demonstrating the shape of the through hole in the joint joint structure which concerns on 1st Embodiment. It is a schematic plan view for demonstrating another shape of the through hole in the joint joint structure which concerns on 1st Embodiment. It is a schematic plan view for demonstrating another shape of the through hole in the joint joint structure which concerns on 1st Embodiment. It is a schematic plan view for demonstrating another shape of the through hole in the joint joint structure which concerns on 1st Embodiment. It is a schematic plan view for demonstrating another shape of the through hole in the joint joint structure which concerns on 1st Embodiment. It is a schematic plan view for demonstrating another shape of the through hole in the joint joint structure which concerns on 1st Embodiment. It is a schematic cross-sectional view for demonstrating the rivet provided with the flange protrusion part. It is a schematic cross-sectional view for demonstrating the rivet provided with the recess. It is a schematic plan view for demonstrating the adhesive layer or the seal layer provided in the member which concerns on 1st Embodiment. It is the schematic sectional drawing for demonstrating an example of the joint joint structure which concerns on 1st Embodiment. It is the schematic sectional drawing for demonstrating an example of the joint joint structure which concerns on 1st Embodiment. It is the schematic sectional drawing for demonstrating an example of the joint joint structure which concerns on 1st Embodiment. It is sectional drawing of the B pillar which is an example of the automobile part which concerns on one Embodiment of this invention. It is sectional drawing of the bumper which is an example of the automobile parts which concerns on one Embodiment of this invention. It is a perspective view of the bumper which is an example of the automobile parts which concerns on one Embodiment of this invention.

Hereinafter, embodiments of the present invention will be described with reference to examples, but it is obvious that the present invention is not limited to the examples described below. In the following description, specific numerical values and materials may be exemplified, but other numerical values and materials may be applied as long as the effects of the present invention can be obtained. In addition, the components of the following embodiments can be combined with each other.

[First Embodiment]
In the method for manufacturing a joint joint structure according to the present embodiment, a shaft portion of a rivet including a shaft portion and a flange provided at the first end portion in the axial direction of the shaft portion is passed through a through hole of the first member. , The first member is brought into contact with the flange and fixed, the shaft portion of the rivet is passed through the through hole of the second member, the first member and the second member are overlapped, and the second end portion in the axial direction of the shaft portion. To crimp the first member and the second member. In other words, the method for manufacturing a joint joint structure according to the present embodiment is a method for manufacturing a joint joint structure for joining a plurality of members by fastening members, and the first member and through holes provided with through holes are A step of preparing one or a plurality of provided second members and a fastening member having a flange portion and a shaft portion, a step of inserting the fastening member into the through hole of the first member, and a flange portion of the fastening member are provided. The step of joining the first end portion located on the end side and the first member, the step of inserting the shaft portion of the fastening member into the through hole of the second member, and the step of inserting the shaft portion of the fastening member into the other end side of the fastening member. It is characterized by including a step of deforming a second end portion located.

In the method for manufacturing a joint joint structure having the above configuration, a rivet is inserted through a through hole of the first member before the first member and the second member, which are the members to be joined, are overlapped with each other, and the first member and the rivet are inserted. To join. As a result, it is possible to prevent the rivet from falling off when the first member is moved, and the production yield is not impaired. Further, by adopting a joint structure using rivets, the cross tensile strength can be increased.

Next, the procedure for manufacturing the joint structure of the present embodiment will be described.

First, a first member 100 having a through hole 101 formed therein, one or more second members 200 provided with a through hole 201, and a rivet (fastening member) 300 having a shaft portion 301 are prepared. In the example of the present embodiment, the case where two plate members are joined, that is, the case where the second member 200 is one will be described as an example, but the present invention will be described even if the number of the second member 200 is two or more. As long as the requirements of the above are satisfied, the effects peculiar to the present invention can be obtained. In the example of this embodiment, the rivet 300 has a shaft portion 301, a first end portion 302, a second end portion 303, and a flange 304 provided on the first end portion 302.

As a specific means for joining the first end portion 302 provided with the flange 304 and the first member 100, for example, as shown in FIG. 1, a flange protrusion 308 is provided on the seat surface of the flange 304, and the flange protrusion is provided. It is conceivable to perform projection welding of the portion 308 and the first member 100. Further, as another example of a specific means for contacting and fixing the first member 100 with the flange 304, it is conceivable to provide a recess 310 in the shaft portion 301 and crimp the first member 100 as shown in FIG. Be done.
First, the former will be described. As shown in FIG. 1, the shaft portion 301 of the rivet 300 is passed through the through hole 101 of the first member 100. In the example of this embodiment, the flange 304 is provided on the first end 302 side of the rivet 300. As shown in FIG. 1, a flange protrusion 308 is provided on the seat surface of the flange 304. The bearing surface of the flange is a surface of the flange facing the axial direction of the rivet, which faces the second end side of the rivet. In other words, the bearing surface of the flange is the surface that comes into contact with the first member to which the flange is fastened. The flange protrusion 308 is arranged so as to be in contact with the surface of the first member. FIG. 1 is a cross-sectional view of the first member 100 in a direction parallel to the plate surface. The first end 302 includes a flange 304.

Next, as shown in FIG. 2, the flange 304 of the rivet 300 and the surface (100a and 100b) of the first member 100 where the rivet 300 is not in contact with the pair of electrodes (first electrodes 1010 and 1020) are not in contact with each other. Insert 100a and. Then, a pair of electrodes (first electrodes 1010 and 1020) come into contact with the flange 304 of the rivet 300 and the surface 100a of the surfaces (100a and 100b) of the first member 100 that the rivet 300 does not touch, and these are brought into contact with each other. The flange 304 and the first member 100 are pressurized in a direction parallel to the axis of the shaft portion 301 of the rivet 300. Then, the pair of electrodes (first electrodes 1010 and 1020) are energized to generate resistance heat generation in the flange protrusion 308 of the flange 304 of the rivet 300 and the first member 100.

Due to this resistance heat generation, a part of the flange protrusion 308 and the first member 100 is pressure-welded or melted, and a part of the flange 304 of the rivet 300, that is, the flange is applied by the pressing force between the pair of electrodes (first electrodes 1010 and 1020). The protrusion 308 and a part of the first member 100 in contact with the protrusion 308 are joined. When the step of bringing the first member 100 into contact with the flange 304 and fixing it is completed, the rivet does not fall, which contributes to the improvement of productivity.

For example, the above steps may be carried out on a small parts assembly line, an assembly line, etc. in the actual assembly line. Then, from the step of stacking the first member 100 and the second member 200 as described later, another assembly line may be used.

For example, when the method of the present embodiment is applied to the manufacture of a vehicle body, a first member provided with a through hole and one or a plurality of second members provided with a through hole in a line for assembling individual parts such as pillars. A step of preparing a rivet having a member and a shaft portion, a step of passing the shaft portion of the rivet through a through hole of the first member, and a step of bringing the first member into contact with a flange and fixing the rivet are performed to carry out the rivet. In the assembly line of the car body, the process of overlapping the first member and the second member through the shaft part of the rivet through the through hole of the second member and the process of deforming the second end part of the shaft part are deformed. The step of crimping the first member and the second member may be carried out. This eliminates the need for rivet supply equipment such as rivets in the vehicle body assembly line where versatility is required.

Next, as shown in FIG. 3, the shaft portion 301 of the rivet 300 fixed to the first member 100 is passed through the through hole 201 of the second member 200 via a flange. That is, the second member 200 is superposed on the surface 100a side of the surface (100a and 100b) of the first member 100 to which the flange 304 of the rivet 300 is not joined. When the first member 100 and the second member 200 are overlapped with each other, the first member 100 and the second member 200 may be in contact with each other at a place other than the vicinity of the through holes 101 and 201, or these. The members may be separated from each other. In the examples of FIGS. 3 to 5, the flange protrusion 308 is crushed and its height is slightly lowered.

Next, the second end portion 303 in the axial direction of the shaft portion 301 is deformed to crimp the first member 100 and the second member 200 (so-called riveting). In the example shown in FIG. 4, the rivet 300 is sandwiched between a pair of electrodes (second electrodes 2010 and 2020), the rivet 300 is pressurized, and the pair of electrodes (second electrodes 2010 and 2020) are energized to energize the rivet 300. Causes resistance heat generation.

In this step, a pair of electrodes (second electrodes 2010 and 2020) come into contact with the end surface 302a of the first end portion 302 of the rivet 300 and the end surface 303a of the second end portion 303. The pair of electrodes pressurize the rivet 300 in a direction parallel to the axis of the shaft portion 301 through them.

Further, in this step, the rivet 300 is softened by energizing the pair of electrodes (second electrodes 2010 and 2020) to generate resistance heat generation in the rivet 300. In this state, by pressurizing the rivet 300 with a pair of electrodes (second electrodes 2010 and 2020), the second end portion 303 of the rivet 300 is deformed. In the example of this embodiment, as shown in FIG. 5, the second end portion 303 is deformed to form the plastic deformed portion 306. In this deformation, the shaft portion 301 is reduced in the axial direction of the shaft portion 301, and the second end portion 303 expands in the out-of-diameter direction of the shaft portion 301, whereby the plastic deformed portion 306 is formed.

Through the above steps, the joint joint structure 1 as shown in FIG. 5 is obtained. The joint structure 1 of FIG. 5 includes a rivet 300, a first member 100, and a second member 200, and the rivet 300 is provided on the shaft portion 301 and the first end portion 302 in the axial direction of the shaft portion 301. The shaft portion 301 passes through the through hole 101 of the first member 100, the shaft portion 301 passes through the through hole 201 of the second member 200, and the first member 100 is in contact with and fixed to the flange 304. Further, the first member 100 and the second member 200 are crimped by the flange 304 of the rivet 300 and the second end portion 303 in the axial direction of the shaft portion 301. In other words, the joint structure 1 of FIG. 5 is a joint structure in which a plurality of superposed members (first member 100 and second member 200) are joined by using the fastening member 300, and the fastening member 300 is , The shaft portion 301, the first end portion 302 provided on one end side of the shaft portion 301, the flange portion 304, the protrusion 308, and the other end side of the shaft portion 301. It has a second end portion 303 and the like. In this joint structure 1, the shaft portion 301 penetrates the first member 100 and the second member 200, and the first member 100 and the second member 200 are crimped by the first end portion 302 and the second end portion 303. The first end portion 302 is joined to the first member 100. Further, the protrusion 308 and the first member 100 are joined.

In the joint joint structure 1 having the above configuration, the cross tensile strength as the joint structure increases.

The configuration of the first member 100 or the second member 200 is not particularly limited. For example, when the first member 100 and the second member 200 are made of a metal material such as a steel plate, particularly a high-strength steel plate (for example, a steel plate having a tensile strength TS of about 590 MPa or more), the strength of the rivet 300 is improved. It is preferable to be able to do it.

In the method for manufacturing a joint structure according to the present embodiment, it is more preferable that the tensile strength of the first member 100 or the second member 200 is 980 MPa or more. Since the rivet joining method according to the present embodiment does not cause embrittlement in the high-strength steel plate, which causes a decrease in the cross tensile strength, a joint joint having a high cross tensile strength when applied to joining a high-strength steel plate. The structure can be provided.

More preferably, the first member 100 or the second member 200 is a steel plate having a tensile strength of 1180 MPa or more, and more preferably a steel plate having a tensile strength of 1500 MPa or more. The upper limit of the tensile strength of the steel plate constituting the first member 100 or the second member 200 is not particularly limited, but may be, for example, 2700 MPa or less.

Further, when a welded portion is formed on a high-strength steel plate by spot welding, the welded portion and its vicinity are likely to become brittle, which may lead to a decrease in cross tensile strength. However, since the joint joint structure according to the present embodiment does not have such a factor of embrittlement, it is possible to provide a joint joint structure having high cross tensile strength when applied to joining high-strength steel sheets. can.

The first member 100 or the second member 200 may be a plate material. Further, the first member 100 may be a steel plate, an aluminum plate, a titanium plate, an alloy plate thereof, or the like. The first member 100 is preferably made of a metal material because it is preferable to employ welding or caulking as a method of joining with the rivet 300 described above. The second member 200 may be a steel plate, an aluminum plate or a titanium plate, an alloy plate thereof, or a non-metal material such as CFRP (Carbon Fiber Reinforced Plastics). Further, the plurality of members may be made of different materials. For example, a combination of a steel plate and an aluminum plate, or a combination of a steel plate and a CFRP plate may be used.

Further, the first member 100 or the second member 200 may be subjected to various surface treatments. For example, the first member 100 or the second member 200 is a base metal by GA plating, GI plating, EG plating, Zn-Mg plating, Zn-Al plating, Zn-Al-Mg plating, Al plating, painting, and hot stamping. It may have a plating layer made of Zn-based plating (Zn—Fe, Zn—Ni—Fe) and Al-based plating (Al—Fe—Si) alloyed with the above.

The thickness of the first member 100 or the second member 200 is also not particularly limited, and has, for example, a thickness of 0.5 mm to 3.6 mm per steel plate in the depth direction of the through hole 101 or 201. You may. Further, the thicknesses of these members may be different from each other. The total plate thickness of the first member and the second member combined is preferably 9.0 mm or less.

As the first member 100 or the second member 200, for example, two plates having a plate thickness of 1.6 mm and 2.3 mm are stacked, and three plates having a plate thickness of 0.75 mm, 1.8 mm, and 1.2 mm are stacked. It may be stacked. As a range of suitable combinations of the first member 100 or the second member 200, for example, two plates having a plate thickness of about 0.6 mm to 2.9 mm and a plate material having a plate thickness of 0.6 mm to 2.9 mm are stacked, or the plate thickness There are three layers of a plate material of 0.6 mm to 1.6 mm, a plate material of 0.6 mm to 2.9 mm, and a plate material of 0.6 mm to 2.9 mm.

The first member 100 or the second member 200 may be a molded product obtained by cold or hot press molding, cold roll molding, or hydrofoam molding. Further, the member may be formed in a pipe shape.

The configuration of the through hole 101 or 201 is not particularly limited. The shape of the through hole 101 or 201 may be circular, for example, as shown in FIG. 6 in a plan view of the through hole 101 or 201 in the depth direction.

The shape of the through hole is an ellipse as shown in FIG. 7, a polygonal shape as shown in FIG. 8, a fan shape as shown in FIG. 9, and one as shown in FIG. 10 in a plan view in the depth direction of the through hole. It may be a circular shape having a convex portion or a cross shape as shown in FIG. Further, the shape of the rear portion may be a shape having a concave portion in a part. By adopting these shapes as the through holes, it is possible to prevent the members from relatively rotating or rattling around the rivet 300 even if the members are not firmly fixed to each other.

The shape of the through hole may be a polygon such as a quadrangle, a pentagon, a hexagon, or an octagon. The corners of these polygons may have curvature. Further, the shape of the through hole may be different for each member.

The size of the through hole 101 or 201 needs to be larger than the diameter of the shaft portion 301 of the rivet 300.

Further, the size of the through hole 101 or 201 may be constant in the depth direction thereof. On the other hand, it may be a stepped shape in which the size of the through hole 101 or 201 changes stepwise along the depth direction, or a tapered shape in which the size of the through hole 101 or 201 gradually changes.

The through hole 101 or 201 can be formed by any means such as laser cutting, punching with a die, and drilling with a drill. For example, when the first member 100 or the second member 200 is a hot stamped steel plate, it is desirable that the means for forming the through holes is hot stamping of a die or laser cutting.

The diameter of the through hole 101 or 201 (converted to the equivalent circle diameter when the through hole is not circular) may be the same for all members or may be different for each member. In normal rivet joining, it is considered preferable to make the diameter of the through hole 101 or 201 constant from the viewpoint of reducing the gap between the joints. The degree of difference in diameter of the through hole 101 or 201 is not particularly limited, but for example, the difference in diameter of the through hole in the adjacent member is preferably in the range of 0.3 mm to 3.0 mm.

It is desirable that the minimum value of the diameter of the through hole 101 or 201 is 0.1 mm to 5.0 mm larger than the maximum value of the diameter of the shaft portion 301 of the rivet 300 to be inserted. This is because if this difference is smaller than 0.1 mm, the insertability deteriorates, and if it is larger than 5.0 mm, it becomes difficult to sufficiently fill the gap of the through hole 101 or 201 with the deformed rivet 300. More preferably, it is in the range of 0.3 mm to 3.0 mm, and optimally it is in the range of 0.3 mm to 1.5 mm. Further, the deviation of the central axes of the through holes 101 and 201 between the plurality of materials to be joined is preferably 1.50 mm or less, and more preferably 0.75 mm or less.

The size of the through hole 101 or 201 may be constant in the depth direction of the first member 100 or the second member 200. On the other hand, a stepped shape or a tapered shape in which the sizes of the through holes 101 or 201 are different in the depth direction may be applied to the through holes 101 or 201. Further, the central axes of the through holes between the plurality of materials to be joined do not have to be the same.

The depth direction of the through hole 101 or 201 may coincide with the axial direction of the shaft portion 301 of the rivet 300.

The configuration of the rivet 300 is also not particularly limited, and can be appropriately selected depending on the thickness and mechanical properties of the first member 100 and the second member 200, which are the materials to be joined, and the sizes of the through holes 101 and 201. .. For example, the diameter of the shaft portion 301 of the rivet 300 (when the cross section of the shaft portion 301 is not circular, it is converted into the equivalent circle diameter of the shaft portion 301) may be 3.0 mm or more from the viewpoint of ensuring the joint strength. .. Further, if the shaft diameter of the rivet 300 is too large, the current density may decrease and the rivet may not soften easily. Therefore, the upper limit of the shaft diameter may be 12.0 mm or less.

The length of the shaft portion 301 (the value obtained by subtracting the thickness of the flange 304 of the first end portion 302 from the length of the rivet 300) needs to be larger than the total thickness of the first member 100 and the second member 200. Yes, in the case of a rivet having a flange, it is more preferably within the following range.
(Total thickness of members + Diameter of shaft x 0.3) ≤ Length of shaft ≤ (Total thickness of members + Diameter of shaft x 2.0)

By setting the length of the shaft portion 301 of the rivet 300 to "total thickness of the first member 100 and the second member 200 + diameter of the shaft portion 301 x 0.3" or more, the second end portion of the shaft portion 301 is formed. The size of the plastic deformed portion 306 after deforming the 303 can be secured, and the joint strength can be further increased. By setting the length of the shaft portion 301 to "total thickness of the first member 100 and the second member 200 + diameter of the shaft portion 301 x 2.0" or less, the manufacturing efficiency can be improved. The total thickness of the members is the total thickness of the first member 100 and the second member 200 to be superposed in the depth direction of the through hole.

The diameter of the shaft portion 301 may be constant. Alternatively, the shape of the shaft portion 301 may be a shape in which the diameter of the shaft portion 301 decreases toward one end of the rivet 300 (so-called tapered shape). A tapered portion may be formed over the entire shaft portion 301, or a tapered portion or a hemispherical portion may be formed only on a part of the shaft portion 301. The tapered or hemispherical rivet 300 is more preferable because it can be easily inserted into the through hole 101 or 201.

As shown in FIG. 1 and the like, the shape of the first end portion 302 of the rivet 300 may be a general flange shape. For example, the shape of the first end portion 302 may be a hemispherical shape (so-called round head), a disk shape (so-called flat head), or a shape having a flat surface side and a conical root (so-called countersunk head). The shape of the first end portion 302 including the flange 304 in a plan view of the shaft portion 301 of the rivet 300 can be a polygon such as a circle, a quadrangle, or a hexagon. A recess for positioning the electrode may be provided at the center of the first end portion 302 on the electrode side.

The rivet 300 needs to be made of metal such as steel, stainless steel, titanium, and aluminum. For example, when the member is a steel plate, the rivet 300 is preferably a steel material such as carbon steel. The rivet 300 may not be surface-treated, but may be surface-treated if corrosion resistance is required. For example, the surface of the rivet 300 may be subjected to zinc-based plating, aluminum-based plating, chrome-based plating, nickel-based plating, chromate treatment, or the like. Stainless steel rivets are desirable, especially when corrosion resistance is required or when used without post-painting. The rivet is manufactured, for example, by cutting a coil wire and cutting or cold forging. From the viewpoint of productivity, cold forging is desirable. The rivet may be left as it is processed, but if the rivet is made of steel, the rivet may be cold forged to produce the rivet, and then quenched and tempered. By increasing the hardness of the entire rivet including the flange 304 by the heat treatment, the joint strength is further improved.

In the method for manufacturing a joint structure according to the present embodiment, it is more preferable that one or more of the first member 100 and the second member 200 is a steel plate, and the rivet 300 is a steel material. This has the effect of suppressing corrosion due to contact with dissimilar metals. In particular, when the first member 100 and the second member 200 are high-strength steel materials, it is more preferable that the rivet 300 is also a high-strength steel material having appropriate strength.

Pressurization and energization by the electrodes ( first electrodes 1010 and 1020, second electrodes 2010 and 2020) are not particularly limited as long as the rivet 300 is deformed into a desired shape.

(1st electrode)
As shown in FIG. 2, the structure of the first electrodes 1010 and 1020 is such that one of the pair of electrodes can support the first end 302 of the rivet 300 (first electrode 1020) and the other is the rivet 300. It is necessary that the shape (first electrode 1010) is in contact with the surface 100a of the first member 100 without being in contact with the shaft portion 301 of the first member 100. This is because it is necessary to prevent variations in the joint state between the first member 100 and the flange 304 due to the diversion to the shaft portion 301. Therefore, it is desirable that the shaft portion 301 and the first electrode 1010 are separated by an insulating material such as bakelite.

The structure of the first electrode is not particularly limited. For example, electrodes for weld bolt welding can be pressurized and energized. Therefore, the joining according to the present embodiment may be performed using this. The shape of the electrode can be appropriately selected according to the shape of the rivet. Examples of the electrode material include chrome copper, alumina-dispersed copper, and chrome zirconium copper, which have excellent conductivity. The shapes of the pair of electrodes arranged one above the other may be different.

As shown in FIG. 12, a flange protrusion 308 is provided on the seat surface of the flange 304. Then, in the step of joining the first end portion 302 and the first member 100, the flange 304 and the first member 100 are joined by projection welding via the flange protrusion 308.

The shape of the flange protrusion 308 includes a circular shape, a polygonal shape, a crescent shape, and a ring shape surrounding the shaft portion. Since the rivet 300 is joined to the first member 100 by the flange 304, the diameter of the first end portion 302 including the flange 304 may be made larger than the diameter of the through hole 101 of the first member 100 by 3.0 mm or more. preferable.

Further, the flange protrusion 308 preferably has a height of 0.5 mm to 3.0 mm and a width of 1.0 mm or more. Optimally, the height of the flange protrusion 308 is 0.7 mm to 1.6 mm. Optimally, the width of the flange protrusion 308 is 1.4 mm to 3.6 mm. The number of flange protrusions 308 is more preferably 3 or 4.

Further, it is more preferable that the thickness of the flange 304 is 0.8 mm to 5.0 mm. If the thickness of the flange 304 is less than 0.8 mm, sufficient joint strength cannot be obtained. On the other hand, if the thickness of the flange 304 is more than 5.0 mm, the flange (head) is too large and interference with other parts is likely to occur.

Pressurization is started before energization. For example, the rivet 300 and the first member 100 are sandwiched between a pair of electrodes (first electrodes 1010 and 1020) and energized in a pressurized state, and the current due to the energization is concentrated on the flange protrusion 308 of the rivet 300. A joint may be formed between the member 100 and the member 100. By starting pressurization before energization, energization can be stabilized.

The pressurizing condition and energizing condition (current value, voltage value, energizing time, etc.) of the rivet 300 are not particularly limited, and can be appropriately selected according to the shape and material of the rivet 300.

As more preferable pressurizing conditions and energizing conditions for the rivet 300, for example, the following can be adopted. Although the description of the voltage value is omitted, the voltage value is determined according to the rivet 300 and the current value.

The pressing force by the first electrodes 1010 and 1020 is preferably 150 kgf to 1000 kgf because a stable energization region can be secured. More preferably, the pressing force is 250 kgf to 600 kgf. The set value of the pressing force may be a constant value, but if necessary, the pressurizing value may be changed during energization.

The energizing time is preferably 0.05 seconds to 1.00 seconds because the joint can be obtained without overheating the member. More preferably, the energizing time is 0.07 seconds to 0.30 seconds.

The current value is preferably 6 kA to 18 kA because a good joint is formed. The energization may be performed once or twice or more. If hardening of the joint is a problem, tempering of the joint may be performed. For example, after the first energization, the joint can be cooled once by continuing to pressurize without passing current, and then the joint can be burnt back by performing the second energization with a current value lower than the first. can. Further, pulse energization, an upslope that gradually increases the current, and a downslope that gradually decreases the current may be energized. The holding time from the end of energization to the end of pressurization is preferably 0.01 to 1.00 seconds because the bonding strength is stable.

The rivet 300 is inserted into the through hole 101 of the first member 100 by, for example, a rivet supply device.

(2nd electrode)
The structure of the second electrode is also not particularly limited. For example, since the electrode for spot welding can be pressurized and energized, the bonding according to the present embodiment may be performed using this. The shape of the electrode can be appropriately selected according to the shape of the rivet. The second electrode may be, for example, a flat type electrode, a single R type, a CF type, or a DR type. Examples of the electrode material include chrome copper, alumina-dispersed copper, and chrome zirconium copper, which have excellent conductivity. The upper and lower electrode shapes may be different.

The power supply of the welding machine includes single-phase AC, DC inverter, and AC inverter. Examples of the gun type include stationary type, C type, and X type.

It is desirable that the pressurizing direction of the rivet by the electrode is an angle of 10 ° or less with respect to the direction in which the axis of the rivet extends, from the viewpoint of obtaining a good joint. More preferably, it is 4 ° or less.

The number of times of energization may be one (so-called single energization), but if necessary, tempering temper energization may be performed by adjusting two-stage energization, three-stage or more multi-stage energization, or current. Further, pulse energization, an upslope that gradually increases the current, and a downslope that gradually decreases the current may be energized. Further, a high current may be passed in the first half of energization to form a softened portion, and the current may be lowered in the second half.

The current may be a single energization that energizes only once, but if necessary, a two-stage energization or a three-stage multi-stage energization may be used. But it's okay. Further, a high current may be passed in the first half of energization to soften the rivet, and the current may be lowered in the second half.

In the step of deforming the second end portion 303 of the rivet 300 after the step of inserting the shaft portion 301 of the rivet 300 into the through hole 201 of the second member 200, the pressurization is started before the energization. For example, the rivet 300 may be sandwiched between a pair of electrodes (second electrodes 2010 and 2020) and energized in a pressurized state, and the rivet 300 may be softened and crimped by the resistance heat generation of the rivet 300 itself due to the energization. By starting pressurization before energization, energization can be stabilized.

The pressurizing condition and energizing condition (current value, voltage value, energizing time, etc.) of the rivet 300 are not particularly limited, and can be appropriately selected according to the shape and material of the rivet 300.

As more preferable conditions for the rivet 300, for example, the following can be adopted. Although the description of the voltage value is omitted, the voltage value is determined according to the rivet 300 and the current value. When the diameter of the shaft portion 301 of the rivet 300 is increased, one or both of the current value and the energization time may be increased to increase the amount of heat input.

The pressing force by the electrode is preferably 150 kgf to 1000 kgf because it can be applied by a general spot welder. More preferably, the pressing force is 250 kgf to 600 kgf. The set value of the pressing force may be a constant value, but if necessary, the pressing force may be changed during energization. When blow holes occur in the softened rivets, a down slope may be used for energization, or the pressing force may be increased in the latter half of energization or after the end of energization in order to crush the blow holes. Further, the pressing force may be changed during the holding time after the end of energization.

The energizing time is preferably 0.15 seconds to 2.00 seconds because it is a time that can be sufficiently softened and is excellent in productivity in a short time. More preferably, the energizing time is 0.20 seconds to 1.00 seconds.

The current value of 4 kA to 13 kA is preferable because it can be stably softened within the above-mentioned energization time.
The holding time from the end of energization to the end of pressurization is preferably 0.01 to 1.00 seconds because it is short and highly productive.

Alternatively, the rivet may be cooled after pressurization and energization. The cooling conditions of the rivet are not particularly limited. After the energization is completed, the rivet may be left in the air for natural cooling. Further, the rivet may be accelerated and cooled by bringing the electrode through which the refrigerant is circulated inside into contact with the rivet. By accelerating and cooling the rivet, the rivet can be hardened and the joint strength of the joint can be further increased. Accelerated cooling may be performed using a holding time, which is the time from the end of energization to the release of the electrodes, and the time for accelerated cooling (holding) is preferably 3 seconds or less from the viewpoint of improving productivity. The holding time is more preferably 0.01 seconds or more and 1.00 seconds or less from the viewpoint of improving productivity and ensuring joining quality. The holding time is optimally 0.10 seconds or more and 0.80 seconds or less.

The tip of the shaft portion 301 of the rivet 300 is plastically deformed by pressurization and energization to form the plastic deformation portion 306. The flange 304 has a function of sandwiching (caulking) the first member 100 and the second member 200 together with the plastically deformed portion 306.
The thickness of the plastically deformed portion 306 is preferably 0.8 mm to 5.0 mm for the purpose of ensuring the joint strength and preventing interference with other parts.

As one embodiment of the present invention, in the step of joining the first end portion 302 of the rivet 300 and the first member 100 (the step of bringing the first member 100 into contact with the flange 304 and fixing it), the first end portion 302 and the first member 1 member 100 may be joined by caulking.

Next, a method of caulking to join the first end portion provided with the flange and the first member will be described. In this method, as shown in FIG. 13, the shaft portion 301 of the rivet 300 has a shaft protrusion 309 protruding in the radial direction of the shaft portion 301. The radial direction of the shaft portion 301 is a direction from the shaft core of the shaft portion 301 toward the outer circumference. By crimping the first member 100 with the shaft protrusion 309, the first member 100 can be brought into contact with the flange 304 and fixed. Specifically, the first member 100 is fitted between the shaft protrusion 309 and the flange 304, and then the shaft protrusion 309 is arbitrarily plastically deformed toward the flange 304 to make the first member 100 shaft protrusion. It can be crimped in part 309.
As shown in FIG. 13, a recess 310 that surrounds the shaft portion 301 is provided in the vicinity of the seat portion (the surface that contacts the first member 100) of the first end portion 302, and the recess 310 provides the first member. The edge of the through hole 101 of 100 may be crimped. The recess 310 is, for example, a space between the shaft protrusion 309 and the flange 304 described above. Specifically, first, the shaft portion 301 of the rivet 300 is inserted into the through hole 101 of the first member 100 to which the rivet 300 is attached, and the first end portion 302 is pushed toward the member by a punch. As a result, the peripheral edge of the through hole 101 of the first member 100 is fitted into the recess 310. In this way, the rivet 300 can be joined to the first member 100 by the flange 304 and the recess 310 of the rivet 300. Further, after this step, the back surface of the first member 100 (the surface opposite to the flange 304) is deformed toward the flange 304 by a punch having a protrusion, and a part of the first member 100 is formed into a recess 310. It may be joined more firmly by pushing it further into the flange. A protrusion may be provided on the first member 100 side of the flange 304, but it is preferable not to provide the protrusion.

In the method for manufacturing a joint structure according to the present embodiment, it is not hindered to use other joining means together. By combining two or more different types of joining means, the joining strength of the joined joint structure can be further increased.

For example, in the method for manufacturing a joint joint structure according to the present embodiment, one or more welding methods selected from the group consisting of _{spot welding, laser welding, and arc welding (MAG welding, MIG welding, CO 2 welding, plasma welding).} Depending on the method, the first member 100 and the second member 200, the second member 200 may be joined to each other (when there are a plurality of second members 200), or all the members may be joined to each other. Welding may be performed before or after riveting. Further, a welding step may be included in the rivet joining step. For example, the present embodiment comprises fixing a rivet to a first member, superimposing the first member and the second member, performing spot welding at a position different from the rivet joining, and then caulking and joining the rivet. The method for manufacturing a joint structure according to the above may be possessed. At this time, the rivet before caulking is desirable because it shows a role as a positioning pin and contributes to improvement in assembling accuracy of the parts to be joined.

Further, in the method for manufacturing a joint joint structure according to the present embodiment, among the first member 100 and the second member 200, an adhesive layer or a seal layer is provided around the through holes 101 and 201, and the adhesive layer or the seal layer is the first. The member 100 and the second member 200 may be sandwiched. In other words, before the step of inserting the shaft portion 301 of the rivet 300 into the through hole 201 of the second member 200 and superimposing the first member 100 and the second member 200, the first member 100 or the second member 200 , At least a step of providing an adhesive layer or a seal layer around the through hole 101 or 201 may be further provided. The joint joint structure thus obtained includes an adhesive layer or a seal layer around the shaft portion 301, and the first member 100 and the second member 200 sandwich the adhesive layer or the seal layer.

The adhesive layer improves rigidity and vibration resistance, and also improves joint strength. In addition, the seal layer improves water resistance and corrosion resistance. In spot welding of members, it may be necessary to separate, for example, an adhesive application portion and a spot welded portion in order to prevent explosion. However, the method for manufacturing a joint joint structure according to the present embodiment has an advantage that the location where the adhesive layer or the seal layer is provided is not limited because the explosion does not occur. In addition, it is possible to prevent contact corrosion of the overlapping surfaces in joining dissimilar metals or metals to CFRP. Further, the sealer may be applied so as to cover at least one of the flange 304 and the plastically deformed portion 306. This makes it possible to prevent water from entering through the gap between the flange 304 or the plastic deformed portion 306 and the steel plate. Furthermore, in the case of joining dissimilar metals or joining metal and CFRP, rivets are placed on at least one metal plate. Chemical conversion treatment and painting may be applied before joining. As a result, contact corrosion between dissimilar materials can be further suppressed and corrosion resistance can be improved.

As the adhesive, epoxy type or rubber type is preferably used. In the case of a thermosetting adhesive, the adhesive may be cured by heating in a baking step on an electrodeposition coating line after riveting. In the case of a reaction-curing adhesive, the adhesive is cured by a lapse of time after the rivet bonding. Further, as the sealer, a spot sealer is preferably used. The periphery of the through hole is defined as the overlapping surface of the members around the through hole. Further, as the adhesive layer, a resin adhesive tape such as ionomer may be used.

FIG. 14 illustrates a portion 150 in which an adhesive layer or a seal layer is provided around the through hole 101 of the first member 100.

In the joint joint structure according to the present embodiment, the rivet is formed so that the top surface of the first end and / or the second end is along the axis of the shaft in a cross-sectional view parallel to the axis of the shaft of the rivet. It may be closer to the shaft portion than a position 0.6 mm away from the surface of the first member and / or the second member in the vicinity toward the side away from the shaft portion. Preferably, the top surface of the first end and / or the second end is on the shaft side of the surface (outer surface) of the plate near the rivet. As a result, interference with other parts can be suppressed. In the examples of FIGS. 15 and 17, the top surface 316 of the plastically deformed portion 306 of the rivet 300 is on the shaft portion 301 side (the shaft portion 301 side of the dotted line H) with respect to the surface of the second member 200 in the vicinity of the rivet 300. .. In the example of FIG. 16, the top surfaces 312 and 316 of both the first end portion 302 and the plastic deformation portion 306 of the rivet 300 are such that the first member 100 and the second member 200 in the vicinity of the rivet 300 are respectively. It is on the shaft portion 301 side (the shaft portion 301 side of the dotted line H) with respect to the surface of the member. Here, the surface (outer surface) of the first member 100 or the second member 200 is the surface (outer surface) of each member that is not in contact with other members (the surface 100b of the first member 100 and the surface of the second member 200). It means 200b). The dotted line H in FIGS. 15 to 17 is an extension of the surface of the first member 100 or the second member 200. In FIGS. 15 to 17, the top surface 312 of the first end portion 302 and / or the top surface 316 of the plastic deformation portion 306 is on the shaft portion 301 side of the surface (outer surface) of the plate material in the vicinity of the rivet 300. , The top surface 312 of the first end portion 302 and / or the top surface 316 of the plastic deformed portion 306 may protrude from the outer surface by a maximum of 0.6 mm. That is, in the examples of FIGS. 15 to 17, even if the top surface 312 of the first end portion 302 and / or the top surface 316 of the plastic deformation portion 306 protrudes by 0.6 mm from the dotted line H, it interferes with other parts. The effect of suppressing

By press-molding the first member 100 and / or the second member 200 before or after the rivet joining by the method described above, the first member 100 and / or the second member 200 in the vicinity of the rivet 300 is formed. The top surface 312 of the first end portion 302 and / or the top surface 316 of the plastic deformed portion 306 is directed from the surface of the first member 100 and / or the second member 200 toward the side away from the shaft portion 301. The shaft portion 301 may be closer to the position separated by 0.6 mm. In the example of FIG. 15, the portion of the second member 200 near the rivet 300 is deformed toward the first member 100. In the example of FIG. 16, the portion of the first member 100 near the rivet 300 is deformed toward the second member 200, and the portion of the second member 200 near the rivet 300 is deformed toward the first member 100. In the example of FIG. 17, the portion of the second member 200 near the rivet 300 is deformed toward the first member 100, and the portion of the first member 100 near the rivet 300 is deformed corresponding to the second member 200. .. In addition, in FIGS. 15 to 17, the description of the flange protrusion 308 or the shaft protrusion 309 described above is omitted.

The automobile parts according to the present invention include the joint joint structure according to the above-described embodiment. As a result, it has high bonding strength. Automobile parts are, for example, bumpers and B-pillars, which are important members for ensuring collision safety.

FIG. 18 shows a cross-sectional view of a B-pillar, which is an example of an automobile part according to an embodiment of the present invention, in which members 11 are joined by rivets 410 and 420. Further, FIG. 19 shows a cross-sectional view of a bumper which is an example of an automobile part according to an embodiment of the present invention in which a member 11 is joined by a rivet 510. These automobile parts are joined by the joint joint structure according to the present invention.

FIG. 20 shows an example in which the joint structure according to the above-described embodiment and a welded portion (a welded portion formed by one or more welding methods selected from the group consisting of spot welding, laser welding, and arc welding) are used in combination. Is shown. FIG. 20 is a bumper structure including a structure in which the members 11 are joined. As shown in FIG. 20, for example, the joint joint structure of the present invention (rivet 610 shown by the black circle in FIG. 20) is used at a portion where the stress applied at the time of collision is expected to be high, and at other joint portions, the joint joint structure is used. Inexpensive spot welding (spot welding portion 800 indicated by a white circle in FIG. 20) may be adopted.

In addition, A-pillars, side sills, roof rails, floor members, front side members, rear side members, floor pans, front suspensions, tunnel reinforcements, dash panels, torque boxes, seat frames, seat rails, battery case frames, and theirs. The joint portion between the pillars (the joint portion between the B pillar and the side sill, the joint portion between the B pillar and the roof rail, and the joint portion between the roof cross member and the roof rail) may be an automobile part according to an embodiment of the present invention.

An embodiment of the present invention will be described below.

Examples 1, 2, 3 and 7 shown in Table 1 are examples of the present invention in which two members are riveted by the method described in the above embodiment to prepare a joint joint structure. Further, in Examples 4, 5 and 6, as a comparative example, a joint structure in which two members are spot-welded is produced.

As test materials, a steel plate with a tensile strength of 1.80 GPa class with a plate thickness of 1.6 mm, a steel plate with a tensile strength of 1.50 GPa class with a plate thickness of 1.6 mm, and a steel plate with a tensile strength of 0.78 GPa with a plate thickness of 2.0 mm. A grade steel plate was used.

(Examples 1 to 3)
As the first step, the projection welding method described in the above embodiment was carried out. Specifically, a through hole having a diameter of 7 mm was previously formed in the first member with a laser piercing. As a rivet, a rivet made of low carbon steel with a flange diameter of 15 mm, a shaft portion diameter of 6 mm and a length of 10 mm, and a flange having three hemispherical protrusions with a diameter of 2.5 mm was used for projection welding with the first member. .. The welding conditions were a pressing force of 400 kgf, an energizing time of 0.15 seconds, a current value of 10 kA, and a holding time of 0.1 seconds. The material is a Cu—Cr alloy. The first electrode has a cylindrical shape as shown in FIG. The inner diameter of the cylinder was 8 mm. The second electrode is a flat electrode and is made of a Cu—Cr alloy.

In the second step, a rivet joined to the first member is inserted into the through hole of the second member, which has been previously provided with a through hole having a diameter of 7 mm by laser piercing, and the stud is sandwiched between the electrodes of the spot welder to energize while pressurizing. The stud was deformed and crimped. Using a flat electrode made of Cu—Cr alloy, the pressing force was set to 400 kgf, the energizing time was adjusted to 333 msec, the current value was adjusted to 6 kA to 8 kA, and the holding time was set to 300 msec.

(Example 7)
In Example 7, a carbon steel rivet having a flange diameter of 12 mm, a shaft length of 10 mm, a shaft diameter of 6 mm, and a length of 1.6 mm having a shape as shown in FIG. 13 was used. The rivet was provided with a shaft protrusion having a height of 0.6 mm.

The first step was carried out by the cold caulking method. A through hole having a diameter of 7 mm was previously formed in the first member with a laser piercing. A rivet was inserted into the through hole of the first member, sandwiched between a punch and a die, and pressurized. The first member is plastically deformed by the pressure and is crimped by being press-fitted between the shaft protrusion 309 of the rivet and the seating surface of the flange 304 (that is, the recess 310) as shown in FIG.

In the second step, a rivet joined to the first member is inserted into the through hole of the second member, which has been previously provided with a through hole having a diameter of 7 mm by laser piercing, and the stud is sandwiched between the electrodes of the spot welder to energize while pressurizing. The stud was deformed and crimped. Using a flat electrode made of Cu—Cr alloy, the pressing force was set to 400 kgf, the energizing time was adjusted to 333 msec, the current value was adjusted to 6 kA to 8 kA, and the holding time was set to 300 msec.

(Examples 4 to 6)
In Examples 4 to 6, joining by spot welding was carried out as a comparative example. As the conditions for spot welding, an electrode having a DR type tip of 6 mm was used, and energization was performed at a pressing force of 400 kgf, an energizing time of 333 msc, a current of 7 kA, and a holding time of 300 msec.

CTS was evaluated for these test pieces in accordance with JIS Z3137. The results are shown below.

As shown in Table 1, using the method of the present invention, the CTS of a joint joint joined by rivets was dramatically enhanced as compared with the CTS of a joint joint by spot welding.

Further, in the invention example, when handling the steel plate to which the rivet was joined, the steel plates could be easily joined to each other without the rivet falling off. From this, it is understood that the method for manufacturing the joint joint structure of the present invention is excellent in productivity even in an actual operation line.

The present invention provides a method for manufacturing a joint joint structure capable of providing a structure having excellent productivity and high cross tensile strength, and a joint joint structure and automobile parts having excellent productivity and high cross tensile strength. It has high industrial applicability because it can be used.

1 Joint joint structure 11 Member 100 1st member 100a, 100b Surface of 1st member 101, 201 Through hole 150 Location where adhesive layer or seal layer is provided 200 2nd member 200b Surface of 2nd member 300, 410, 420, 510 , 610 Rivet 301 Shaft 302 1st end 303 2nd end 304 Flange 306 Plastic deformation 308 Flange protrusion 309 Shaft protrusion 310 Recess 312, 316 Top surface 800 Spot welded part 1010, 1020 First electrode 2010, 2020 2nd electrode

Claims (15)

1. Passing the shaft portion of the rivet including the shaft portion and the flange provided at the first end portion in the axial direction of the shaft portion through the through hole of the first member.
   To bring the first member into contact with the flange and fix it.
   The first member and the second member are overlapped with each other by passing the shaft portion of the rivet through the through hole of the second member, and the second end portion of the shaft portion in the axial direction is deformed to form the first member. Crimping the member and the second member,
   A method of manufacturing a joint structure including.
2. A flange protrusion is provided on the bearing surface of the flange.
   The method for manufacturing a joint joint structure according to claim 1, wherein the flange protrusion and the first member are projected welded, and the first member is brought into contact with the flange to be fixed.
3. A shaft protrusion is provided in the radial direction of the shaft, and the shaft protrusion is provided.
   The method for manufacturing a joint joint structure according to claim 1, wherein the first member is crimped by the shaft protrusion and the first member is brought into contact with the flange to be fixed.
4. Any one of claims 1 to 3, wherein the rivet is sandwiched between a pair of electrodes in the axial direction, the rivet is pressurized in the axial direction, and the pair of electrodes are energized to deform the second end portion. A method for manufacturing a joint joint structure according to.
5. The method for manufacturing a joint joint structure according to any one of claims 1 to 4, wherein the first member or the second member is a steel plate, and the rivet is a steel material.
6. Any of claims 1 to 5 for joining the first member and the second member and / or the second member to each other by one or more welding methods selected from the group consisting of spot welding, laser welding, and arc welding. The method for manufacturing a welded joint structure according to item 1.
7. Of the first member and the second member, an adhesive layer or a seal layer is provided around the through hole.
   The method for manufacturing a joint joint structure according to any one of claims 1 to 6, wherein the adhesive layer or the seal layer is sandwiched between the first member and the second member.
8. A rivet, a first member, and a second member are provided.
   The rivet includes a shaft portion and a flange provided at the first end portion of the shaft portion in the axial direction.
   The shaft portion passes through the through hole of the first member and passes through the through hole.
   The shaft portion passes through the through hole of the second member and passes through the through hole.
   The first member is in contact with and fixed to the flange.
   Further, the first member and the second member have a joint structure in which the flange of the rivet and the second end portion of the shaft portion in the axial direction are crimped.
9. A flange protrusion is provided on the bearing surface of the flange.
   The flange protrusion and the first member are welded together.
   The joint structure according to claim 8, wherein the first member is fixed in contact with the flange.
10. A shaft protrusion is provided in the radial direction of the shaft, and the shaft protrusion is provided.
    The joint joint structure according to claim 8, wherein the first member is crimped by the shaft protrusion, and the first member is fixed in contact with the flange.
11. The joint joint structure according to any one of claims 8 to 10, wherein one or more of the first member or the second member is a steel plate, and the rivet is a steel material.
12. An adhesive layer or a seal layer is provided around the shaft portion.
    The joint joint structure according to any one of claims 8 to 11, wherein the first member and the second member sandwich the adhesive layer or the seal layer.
13. The joint joint structure according to any one of claims 8 to 12, wherein the first member and the second member are welded to each other.
14. An automobile part having the joint joint structure according to any one of claims 8 to 13.
15. The automobile part according to claim 14, which is a bumper or a B-pillar.

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