JP7332966B2 - Joint manufacturing method, joint, and automobile part - Google Patents

Description

The technology disclosed by the present application relates to a joint manufacturing method, a joint, and an automobile part.

For example, a projection welding device is known as a device for joining a metal nut to a plate material such as a steel plate (see, for example, Japanese Unexamined Patent Application Publication No. 2019-98385). In this projection welding device, a pair of electrodes are energized while sandwiching a plate material and a nut (projection nut) between the pair of electrodes. A plurality of protrusions are formed at intervals in the circumferential direction of the nut at one axial end of the nut. A plurality of point contact portions between the plurality of convex portions and the plate material are joined by projection welding.

Such joining technology by projection welding is widely used, for example, in joining structures of body panels of automobiles (see, for example, Japanese Patent Application Laid-Open No. 2019-93819). In a body panel joining structure using this joining technique by projection welding, for example, a second body panel member is superimposed on a first body panel member to which a nut (weld nut) is joined. Then, the second vehicle body panel member is joined to the first vehicle body panel member by screwing the bolt inserted through the insertion hole of the second vehicle body panel member into the nut.

The above is a description of a technique for joining a plate and a nut by projection welding. Techniques for fixing nuts to plate materials include the following techniques.

For example, in the first fixing technique, a nut having an inner cylinder and an outer wall at one end in the axial direction of the nut body, that is, a pierce nut is used (for example, JP-A-11-193808, JP-A-11-193808, JP-A-11-193808, See JP-A-2005-240836, Japanese Patent No. 5106279, and Japanese Patent No. 5876405). In this fixing technique using a pierce nut, a nut set on a plate is driven by a driving tool. As a result, part of the plate material is punched out by the inner cylinder of the nut, and a hole is formed in the plate material. The nut is fixed to the plate member by inserting the inner cylinder into the hole and crimping the periphery of the hole between the inner cylinder and the outer wall.

Further, for example, in the second fixing technique, a nut having a flange portion and a trunk portion, that is, a caulked nut is used (for example, Japanese Patent No. 4093674, Japanese Unexamined Patent Publication No. 2001-065525, Japanese Unexamined Patent Publication No. 09- 126215 and Japanese Patent Laid-Open No. 2008-175379). In this fixing technique using a crimped nut, the body of the nut inserted into the hole of the plate material is crushed in the axial direction, thereby forming an annular crimped deformed portion in the body. Then, the nut is fixed to the plate while the plate is sandwiched between the flange portion and the caulking deformation portion of the nut.

However, the conventional technique described above has the following problems. That is, in the body panel joining structure using the joining technology by projection welding, when the bolt passed through the insertion hole of the second body panel material is screwed into the nut joined to the first body panel material, the nut is pushed by the bolt. is pushed. Therefore, a pressing load acts on the nut in the direction in which the nut is separated from the first vehicle body panel member.

Here, in the joining technique by projection welding, the nut and the plate material are not joined by welding over the entire length of the nut in the circumferential direction. The parts are joined by projection welding. As a result, the peel strength of the nut may be insufficient. Moreover, if the melting diameter of the point contact portion is increased in order to increase the peel strength of the nut, spatter may occur. If this spatter adheres to the screw hole of the nut, there is a possibility that the bolt cannot be screwed into the nut.

Further, in the above-described fixing technique using a pierce nut, a screw hole is formed from the nut body to the inner cylinder. Therefore, when a part of the plate material is punched by the inner cylinder of the driven nut, the inner cylinder may be deformed, and the screw hole may be deformed along with the deformation of the inner cylinder.

Also in the fixing technique using a crimp nut, a threaded hole is formed in the body of the nut. Therefore, when the barrel portion is crushed in the axial direction and the crimping deformation portion is formed in the barrel portion, the screw hole may be deformed.

As an example, the technology disclosed in the present application aims to ensure the peel strength of the fastening member and to suppress the difficulty of screwing the male threaded portion of the screw member into the screw hole of the fastening member.

In addition, the technology disclosed in the present application suppresses peeling of the fastening member and difficulty in screwing the male threaded portion of the screw member into the screw hole of the fastening member, and properly connects the first plate member and the second plate member. The second purpose is to join.

A fastening member according to a first aspect is a fastening member including a shaft portion and a flange provided at an axial end portion of the shaft portion, wherein the fastening member has a There is a first through-hole extending through the shank and the flange along, the first through-hole in the flange being a threaded hole, the cross-section of the first through-hole in the cross section of the shank. The diameter is greater than the root diameter of the threaded hole in the cross section of the flange.

A fastening member according to a second aspect is the fastening member according to the first aspect, wherein the outer diameter of the flange is larger than the outer diameter of the shaft portion, and the thickness of the flange is thicker than the thickness of the shaft portion.

A fastening member according to a third aspect is the fastening member according to the first aspect or the second aspect, wherein the shaft portion is a male screw.

A joint joining method according to a fourth aspect includes passing the shaft portion according to any one of the first to third aspects through the second through hole of a first plate having a second through hole. bringing the flange into contact with the first plate member; and crimping the first plate member by crushing the tip of the shaft portion.

A joint joining method according to a fifth aspect is the joint manufacturing method according to the fourth aspect, wherein the outer diameter of the flange is larger than the outer diameter of the shaft portion, and the thickness of the flange is the thickness of the shaft portion. Thicker than thick.

A joint joining method according to a sixth aspect is the joint manufacturing method according to the fourth aspect or the fifth aspect, wherein the second through hole is a screw hole, and the shaft portion is a male screw. , screwing the shaft into the second through hole;

A joint joining method according to a seventh aspect is the method for manufacturing a joint according to the fourth aspect or the fifth aspect, wherein the second through hole is a polygonal hole, and the shaft portion is connected to the second through hole. to engage.

A joint joining method according to an eighth aspect is the joint manufacturing method according to any one of the fourth to seventh aspects, wherein the fastening member is sandwiched between a pair of heating and pressurizing members from both sides in the axial direction. The pair of heating and pressurizing members heats the fastening member and applies pressure to the fastening member in the axial direction, thereby crushing the tip of the shaft portion and crimping the first plate member.

A joint joining method according to a ninth aspect is the joint manufacturing method according to the eighth aspect, wherein the fastening member is made of metal, and the first plate material is a steel plate having a tensile strength of 780 MPa or more. The pair of heating and pressurizing members are a pair of electrodes.

A method for joining a joint according to a tenth aspect is the method for manufacturing a joint according to any one of the fourth to ninth aspects, wherein the third through hole of the second plate member having the third through hole passing the male screw portion of a screw member through, passing the male screw portion through the first through hole of the shaft portion, and screwing the male screw portion into the screw hole to fix the second plate member. , provided.

A method for joining a joint according to an eleventh aspect is the method for manufacturing a joint according to the tenth aspect, wherein the first plate member bulges to the side opposite to the second plate member, and has the second through hole at the top. It has a bulge with a hole.

A joint according to a twelfth aspect includes a plate member having a second through hole, and the first aspect to the first aspect in which the flange is in contact with the plate member in a state where the shaft portion is passed through the second through hole. and a fastening member according to any one of the three aspects, wherein a crimping portion for crimping the plate material with the flange is formed at a tip portion of the shaft portion projecting from the second through hole. .

An automobile component according to a thirteenth aspect includes the joint according to the twelfth aspect.

According to the technology disclosed in the present application, as an example, it is possible to secure the peel strength of the fastening member and to suppress the difficulty of screwing the male screw portion of the screw member into the screw hole of the fastening member.

In addition, the technology disclosed in the present application suppresses peeling of the fastening member and difficulty in screwing the male threaded portion of the screw member into the screw hole of the fastening member, and properly connects the first plate member and the second plate member. can be spliced.

It is a front view which shows the fastening member which concerns on 1st embodiment. It is a longitudinal section showing a fastening member concerning a first embodiment. It is a sectional view explaining the first process of the manufacturing method of the joint concerning a first embodiment. It is a sectional view explaining the second process of the manufacturing method of the joint concerning a first embodiment. It is a sectional view explaining the first process of the board joining method concerning a first embodiment. It is a sectional view explaining the second process of the board joining method concerning a first embodiment. It is a sectional view explaining the first process of the manufacturing method of the joint concerning a second embodiment. It is sectional drawing explaining the 2nd process of the manufacturing method of the joint which concerns on 2nd embodiment. It is sectional drawing explaining the 1st process of the board|plate joining method which concerns on 2nd embodiment. It is sectional drawing explaining the 2nd process of the board|plate material joining method which concerns on 2nd embodiment. It is a front view which shows the fastening member which concerns on 3rd embodiment. It is a longitudinal section showing a fastening member concerning a third embodiment. FIG. 10 is a cross-sectional view for explaining the first step of the joint manufacturing method according to the third embodiment. FIG. 10 is a cross-sectional view for explaining a second step of the joint manufacturing method according to the third embodiment. It is a sectional view explaining the first process of the board joining method concerning a third embodiment. It is sectional drawing explaining the 2nd process of the board|plate material joining method which concerns on 3rd embodiment. FIG. 11 is an exploded perspective view of a joining joint according to a fourth embodiment; It is a sectional view explaining the first process of the manufacturing method of the joint concerning a fifth embodiment. FIG. 11 is a cross-sectional view for explaining a second step of the joint manufacturing method according to the fifth embodiment. It is a front view which shows the nut which concerns on a 1st comparative example. It is a longitudinal cross-sectional view showing a nut according to a first comparative example. FIG. 5 is a cross-sectional view for explaining a first step of a method for manufacturing a joint according to a first comparative example; FIG. 10 is a cross-sectional view for explaining a second step of the joint manufacturing method according to the first comparative example; It is a longitudinal cross-sectional view showing a nut according to a second comparative example. FIG. 10 is a vertical cross-sectional view showing a joint joint according to a second comparative example; FIG. 11 is a vertical cross-sectional view showing a nut according to a third comparative example; FIG. 11 is a vertical cross-sectional view showing a joint joint according to a third comparative example; FIG. 11 is a cross-sectional view for explaining a first step of a method for manufacturing a joint according to a fourth comparative example; FIG. 11 is a cross-sectional view for explaining a second step of a joint manufacturing method according to a fourth comparative example;

[First embodiment]
First, a first embodiment of the present invention will be described.

1A and 1B are diagrams showing the fastening member 10 according to the first embodiment. FIG. 1A is a front view of the fastening member 10. FIG. FIG. 1B is a vertical cross-sectional view of the fastening member 10. FIG. The arrow A1 indicates one axial side of the fastening member 10, and the arrow A2 indicates the other axial side of the fastening member 10. As shown in FIG.

As shown in FIGS. 1A and 1B, a fastening member 10 (eg, rivet nut, nut) has a shaft portion 12 and a flange 11 provided at an axial end of the shaft portion 12 . Further, the fastening member 10 has a first through-hole extending through the shaft portion 12 and the flange 11 along the axial direction of the shaft portion 12 . The fastening member 10 is, for example, made of metal.

The flange 11 (nut body, female screw portion) is formed in an annular shape. A first through hole in this flange 11 is a screw hole 13 . A screw hole 13 is formed in the center of the flange 11 . The entire first through hole in the flange 11 may be the screw hole 13 , or part of the first through hole in the flange 11 may be the screw hole 13 . The shaft portion 12 (cylindrical portion) protrudes from one axial end portion of the flange 11 . This shaft portion 12 is cylindrical. A first through hole in the shaft portion 12 is a through hole 14 . The through hole 14 is formed in the central portion of the shaft portion 12 .

The screw hole 13 and the through hole 14 constitute a first through hole that passes through the fastening member 10 in the axial direction of the shaft portion 12 . The through hole 14 is arranged coaxially with the screw hole 13 and communicates with the screw hole 13 . The outer diameter D1 of the flange 11 is larger than the outer diameter D2 of the shaft portion 12 . The diameter d2 (inner diameter) of the through hole 14 in the cross section of the shaft portion 12 is larger than the root diameter d1 (inner diameter, hole diameter) of the screw hole 13 in the cross section of the flange 11 . Further, the thickness (D1-d1) of the flange 11 is thicker than the thickness (D2-d2) of the shaft portion 12. As shown in FIG. The root diameter d1 of the screw hole 13 means the diameter of an imaginary cylinder in contact with the root of the female thread.

Next, a method for manufacturing a joint according to the first embodiment will be described.

2A and 2B are diagrams for explaining the joint manufacturing method (bonded joint manufacturing method) according to the first embodiment. FIG. 2A is a diagram explaining the first step of the joint manufacturing method. FIG. 2B is a diagram explaining the second step of the joint manufacturing method.

The joint manufacturing method according to the first embodiment is a method of fixing the fastening member 10 to the joined portion 21 of the plate material 20 to obtain the joined joint 30 including the joined portion 21 and the fastening member 10 . The plate material 20 is, for example, a steel plate with a tensile strength of 780 MPa or more, preferably a steel plate with a tensile strength of 980 MPa or more. Further, the plate thickness of the steel plate forming the plate material 20 is, for example, 0.5 mm to 4.0 mm. Note that the plate material 20 may be a surface-treated steel plate. Also, the plate member 20 is an example of a first plate member.

A through hole 22 (through hole) is formed in the joined portion 21 so as to pass through the joined portion 21 in the plate thickness direction. The through hole 22 is a round hole with a circular cross section. The joined portion 21 is a portion within a predetermined range including the through hole 22 . The through hole 22 is an example of a second through hole. In addition, in FIGS. 2A and 2B, only the joined portion 21 of the plate material 20 is shown. The joined portion 21 has a first plate surface 21A and a second plate surface 21B opposite to the first plate surface 21A.

The joint manufacturing method according to the first embodiment includes a first step and a second step as steps for fixing the fastening member 10 to the joined portion 21 .

As shown in FIG. 2A, in the first step, the shaft portion 12 is passed through the through hole 22 from the first plate surface 21A side, and the flange 11 is brought into contact with the peripheral portion of the through hole 22 in the first plate surface 21A of the plate member 20. contact. Also, the tip (tip) of the shaft portion 12 is projected from the second plate surface 21B of the joined portion 21 .

The axial length L of the shaft portion 12 is longer than the plate thickness T of the joined portion 21 . Also, the outer diameter D1 of the flange 11 is larger than the diameter d3 of the through hole 22 . Also, the outer diameter D2 of the shaft portion 12 is smaller than the diameter d3 of the through hole 22 . In order to suppress rattling of the fastening member 10 with respect to the joined portion 21 , it is desirable that the outer diameter D2 of the shaft portion 12 is slightly smaller than the diameter d3 of the through hole 22 . Note that the shaft portion 12 may be press-fitted into the through hole 22 .

As shown in FIG. 2B , in the second step, the fastening member 10 is sandwiched between the pair of electrodes 40 from both axial sides of the fastening member 10 . The pair of electrodes 40 is an example of "a pair of heating and pressurizing members." Then, an electric current is passed between the pair of electrodes 40, and the fastening member 10 is pressurized in the axial direction while the fastening member 10 is energized and heated by the pair of electrodes 40, thereby crushing the tip of the shaft portion 12 and crimping the plate member 20. . As a result, a crimped portion 15 extending radially outward of the shaft portion 12 is formed at the distal end portion of the shaft portion 12 . The crimped portion 15 is formed in an annular shape along the circumferential direction of the shaft portion 12 . The heating and pressing of the fastening member 10 by the pair of electrodes 40 do not necessarily have to be performed simultaneously, and can be performed separately.

At this time, the crimped portion 15 is formed such that the outer diameter D4 of the crimped portion 15 is larger than the diameter d3 of the through hole 22 . As a result, the crimped portion 15 is crimped (locked) to the peripheral portion of the through hole 22 on the second plate surface 21B. That is, the crimped portion 15 formed in a flange shape overlaps the peripheral portion of the through hole 22 in the second plate surface 21B and is caught by the peripheral portion of the through hole 22 .

In this manner, the flange 11 is brought into contact with the periphery of the through hole 22 on the first plate surface 21A. Further, a crimped portion 15 is formed at the tip of the shaft portion 12 to be press-fitted to the peripheral portion of the through hole 22 on the second plate surface 21B. As a result, the fastening member 10 is fixed to the joined portion 21 with the joined portion 21 sandwiched between the flange 11 and the crimped portion 15 . Further, by sandwiching the jointed portion 21 under pressure between the flange 11 and the crimped portion 15 , rotation of the fastening member 10 with respect to the jointed portion 21 is restricted.

By deforming the tip of the shaft portion 12, an extension portion 16 extending radially inward of the shaft portion 12 is formed at the tip portion of the shaft portion 12 in addition to the crimped portion 15 described above. be. The extending portion 16 is formed in an annular shape along the circumferential direction of the shaft portion 12 .

By the way, when the inner diameter d4 of the extending portion 16 is smaller than the root diameter d1 of the screw hole 13, it is possible to screw a bolt into the screw hole 13 from one axial side (arrow A1 side) of the fastening member 10, as described later. It becomes impossible (it becomes impossible to screw in).

Therefore, in the second step, the heating temperature, pressure, and pressure time of the pair of electrodes 40 are adjusted so that the inner diameter d4 of the extension 16 does not become smaller than the root diameter d1 of the screw hole 13. The amount of radially inward deformation of the tip portion of the shaft portion 12 is adjusted depending on the shape and the like. In addition, the size of the diameter d2 of the through hole 14 of the shaft portion 12 before pressure deformation is set so that the inner diameter d4 of the extension portion 16 is not smaller than the root diameter d1 of the screw hole 13 . This prevents the inner diameter d4 of the extending portion 16 from becoming smaller than the root diameter d1 of the screw hole 13 . Furthermore, the through hole 14 of the shaft portion 12 before pressure deformation may be provided with a taper that tapers toward the flange 11 side. This makes it difficult for the shaft portion 12 to deform inward when the shaft portion 12 is deformed in the axial direction.

This second process is not a welding process but a crimping process. Therefore, in the second step, the fastening member 10 is electrically heated and pressurized by the pair of electrodes 40 at a heating temperature that does not melt the part to be joined 21 .

In the second step, since the plate material 20 which is a steel plate is not melted, hydrogen is suppressed from entering the inside of the plate material 20 from the atmosphere or from the rust preventive oil on the surface of the plate material 20 . Further, since the plate material 20 is not rapidly cooled from a high temperature and does not become fresh martensite, the occurrence of hydrogen embrittlement in the plate material 20 is suppressed. These are the advantageous features of the first embodiment compared to projection welding. Hydrogen embrittlement is a phenomenon in which hydrogen absorbed in a steel sheet causes cracks in the steel sheet or decreases the strength (ductility or toughness) of the steel sheet.

In the joint manufacturing method according to the first embodiment, the fastening member 10 is joined to the joined portion 21 formed on the plate member 20 in the manner described above. Thereby, the joining joint 30 including the joined portion 21 and the fastening member 10 is obtained. This joining joint 30 is suitable for automobile parts, for example. Automobile parts having such joints 30 include, for example, body frame members such as A pillars, B pillars, side members, rockers, roof side rails, and bumper reinforcements.

In this joining joint 30 , the fastening member 10 includes a flange 11 having a screw hole 13 and a shaft portion 12 projecting from one axial end (axial end) of the flange 11 . The shaft portion 12 has a through hole 14 formed coaxially with the screw hole 13 . The shaft portion 12 is passed through a through hole 22 formed in the joined portion 21 . The flange 11 is in contact with the periphery of the through hole 22 on the first plate surface 21A. A tip portion of the shaft portion 12 protrudes from the second plate surface 21B of the joined portion 21 . A crimped portion 15 is formed at the distal end portion of the shaft portion 12 and crimped (locked) to the peripheral portion of the through hole 22 in the second plate surface 21B.

Next, a method for joining plate materials according to the first embodiment will be described.

3A and 3B are diagrams for explaining the method for joining plate materials according to the first embodiment. FIG. 3A is a diagram for explaining the first step of the method for joining plate materials. FIG. 3B is a diagram for explaining the second step of the method for joining plate materials.

In the following description, the plate member 20 will be referred to as the first plate member 20 in order to distinguish it from the second plate member 50 and the second joined portion 51 of the plate member joining structure 70 obtained by the plate member joining method. The joining portion 21 is referred to as a first joining portion 21 .

In the method for joining plate materials according to the first embodiment, the second part to be joined 51 of the second plate material 50 different from the first plate material 20 is joined to the first part to be joined 21 of the first plate material 20. It is a way to

The method for joining plate materials according to the first embodiment includes a first step and a second step as steps of joining the second portion to be joined 51 to the first portion to be joined 21 .

As shown in FIG. 3A , in the first step, the second plate material 50 is attached to the first welded portion 21 of the welded joint 30 manufactured by the joint manufacturing method according to the first embodiment described above. are superimposed on each other.

The second joined portion 51 has a bulging portion 53 . The bulging portion 53 has a shape that bulges to the side opposite to the first plate member 20 with respect to the flat portion 54 of the second plate member 50 . A through hole 52 (insertion hole) that penetrates the second plate member 50 in the plate thickness direction is formed at the top of the bulging portion 53 . In the second step, the first to-be-joined portion 21 is positioned so that the tip portion of the shaft portion 12 is positioned inside the bulging portion 53 and the through hole 52 is positioned coaxially with the fastening member 10 . 2 to be joined 51 are positioned. The through hole 52 is an example of a third through hole.

As shown in FIG. 3B, the second step uses bolts 60 . The bolt 60 has a head 61 and a male threaded portion 63 . In this second step, the male threaded portion 63 is passed through the through hole 52 from the second joined portion 51 side, and the male threaded portion 63 is screwed (screwed) into the screw hole 13 of the fastening member 10 . As a result, the first joint portion 21 and the second joint portion 51 are held between the flange 11 of the fastening member 10 and the head portion 61 of the bolt 60 . 2 to-be-joined part 51 is joined. Note that the bolt 60 is an example of a screw member.

In the plate member joining method according to the first embodiment, the first joined portion 21 and the second joined portion 51 are joined using the fastening member 10 and the bolt 60 in the manner described above. As a result, the plate member joining structure 70 including the fastening member 10, the bolt 60, the first joined portion 21, and the second joined portion 51 is obtained.

Such a plate material joining structure 70 is suitable for, for example, a joining structure for a body panel of an automobile, particularly an automobile part including a body panel made of high-strength steel plate. Automobile parts including the plate material joining structure 70 include, for example, body frame members such as A pillars, B pillars, side members, rockers, roof side rails, and bumper reinforcements. This plate material joining structure 70 is particularly suitable for sites (points) where load stress is high. However, it goes without saying that the plate material joining structure 70 may be applied to other than automobile parts.

2A and 2B in the method for manufacturing the joint shown in FIG. The first step and second step (post-step) shown in FIGS. 3A and 3B respectively correspond to the third step and fourth step in the method for joining plate materials according to the first embodiment.

In addition, the joint manufacturing method according to the first embodiment includes passing the shaft portion 12 of the fastening member 10 through the through hole 22 of the first plate member 20 having the through hole 22, and attaching the flange 11 to the first plate member 20. The first plate member 20 is crimped by crushing the tip of the shaft portion 12, and the male screw portion 63 of the bolt 60 as a screw member is inserted into the through hole 52 of the second plate member 50 having the through hole 52. , passing the male screw portion 63 through the through hole 14 of the shaft portion 12 , and screwing the male screw portion 63 into the screw hole 13 to fix the second plate member 50 .

Next, the action and effects of the first embodiment will be described.

According to the first embodiment, in the second step of the joint manufacturing method (see FIG. 2B), the fastening member 10 is sandwiched between the pair of electrodes 40 from both axial sides of the fastening member 10, and the pair of electrodes 40 The fastening member 10 is pressurized while being electrically heated. By crushing the tip of the shaft portion 12, the crimped portion 15 is formed at the tip portion of the shaft portion 12 so as to be press-fitted to the peripheral portion of the through hole 22 in the second plate surface 21B.

Therefore, by crimping the crimped portion 15 to the periphery of the through hole 22 , the crimped portion 15 functions as a retaining portion that is caught by the periphery of the through hole 22 , thereby increasing the peel strength of the fastening member 10 . Accordingly, as shown in FIGS. 3A and 3B, when the male screw portion 63 of the bolt 60 is screwed into the screw hole 13 of the fastening member 10, the fastening member 10 is separated from the first joined portion 21. is applied to the fastening member 10, the separation of the fastening member 10 from the first joined portion 21 is suppressed.

In particular, the crimped portion 15 is annularly formed along the circumferential direction of the shaft portion 12 . Therefore, the first embodiment can increase the peel strength of the fastening member 10, for example, compared to projection welding in which the nut and the first welded portion 21 are joined at a plurality of point contact portions.

Further, according to the first embodiment, in the second step of the joint manufacturing method (see FIGS. 3A and 3B), the pair of electrodes 40 is used to heat the fastening member at a heating temperature at which the first welded portion 21 does not melt. 10 is pressurized while being energized and heated, and the tip of the shaft portion 12 is crushed. That is, in the second step, the fastening member 10 is electrically heated and pressurized under the crimping condition in which the heating temperature of the first welded portion 21 is lower than that in projection welding. Therefore, since the first welded portion 21 does not melt, hydrogen embrittlement in the first welded portion 21 is suppressed. Thereby, the quality of the first welded portion 21 and the welded joint 30 can be ensured.

The fastening member 10 also includes a flange 11 and a shaft portion 12 protruding from one axial end of the flange 11 . The screw hole 13 of this fastening member 10 is not formed in the shaft portion 12 but is formed only in the flange 11 . Therefore, in the second step of the joint manufacturing method (see FIGS. 2A and 2B), when the tip of the shaft portion 12 is crushed to form the caulked portion 15, the screw hole 13 is less likely to deform. Moreover, as described above, in the second step, since the first part to be joined 21 is not melted, adhesion of spatter to the screw hole 13 is suppressed. As described above, it is possible to prevent the male screw portion 63 of the bolt 60 from being difficult to be screwed into the screw hole 13 .

Further, in the second step of the joint manufacturing method, the tip of the shaft portion 12 that is crushed is located away from the flange 11 having the screw hole 13, so deformation of the screw hole 13 is further suppressed. Moreover, since the thickness of the flange 11 is thicker than the thickness of the shaft portion 12, when the fastening member 10 is pressurized while the pair of electrodes 40 is energized, the current density of the flange 11 is greater than the current density of the shaft portion 12. lower than density. Therefore, the temperature of the flange 11 does not rise as compared with the shaft portion 12, so that the deformation of the screw hole 13 of the flange 11 is further suppressed. The thickness of the flange 11 is preferably 1.5 times or more the thickness of the shaft portion 12, for example.

As described above, in the first embodiment, separation of the fastening member 10 and difficulty in screwing the male threaded portion 63 of the bolt 60 into the screw hole 13 of the fastening member 10 are suppressed, and the first plate member 20 and the second plate member 20 are prevented from can be properly joined to the plate material 50 of

Further, in the first embodiment, the through hole 22 of the first joined portion 21 is a round hole having a circular cross section. Therefore, for example, when the plate material joining structure 70 is applied to the joining structure of the vehicle body panel of an automobile, even if a load acts on the first joined portion 21 through the bolt 60 and the fastening member 10, the circumference of the through hole 22 is It is possible to suppress concentration of stress on a part of the portion.

Next, a comparison between the first embodiment and a comparative example will be described.

(Comparison with the first comparative example)
11A and 11B are diagrams showing a nut 110 according to a first comparative example. 11A is a front view of nut 110. FIG. 11B is a vertical cross-sectional view of nut 110. FIG.

A nut 110 according to the first comparative example is a projection nut that is joined to a plate material by a projection welding device. A plurality of projections 115 are formed at one end of the nut 110 in the axial direction. The plurality of protrusions 115 are arranged at intervals in the circumferential direction of the nut 110 .

12A and 12B are diagrams illustrating a method of manufacturing a joint according to the first comparative example. FIG. 12A is a diagram illustrating the first step of the joint manufacturing method. FIG. 12B is a diagram explaining the second step of the joint manufacturing method.

In the joint manufacturing method according to the first comparative example, the nut 110 is set on the joined portion 151 of the plate member 150 in the first step. Next, in the second step, the pair of electrodes 160 is energized with the joined portion 151 and the nut 110 sandwiched between the pair of electrodes 160 .

The nut 110 and the joined portion 151 are joined by projection welding at the plurality of point contact portions between the plurality of convex portions 115 and the joined portion 151 . A plurality of welded portions 116 are formed at the joint portion between the nut 110 and the joint portion 151 by this projection welding. In the joint manufacturing method according to the first comparative example, a joined joint having the nut 110 and the joined portion 151 is obtained in the manner described above.

However, in the first comparative example, the nut 110 and the joined portion 151 are not joined by welding over the entire circumferential length of the nut 110, and the plurality of convex portions 115 formed on the nut 110 and the joined portion 151 are not joined together. are joined by projection welding. Therefore, when the bolt is pushed into the nut 110 , there is a possibility that the peel strength of the nut 110 may be insufficient with respect to the pushing load acting on the nut 110 .

In the first comparative example, particularly when the steel plate strength of the plate material 150 increases, the toughness of the welded portion 116 decreases, so the possibility of insufficient peel strength of the nut 110 increases. In addition, when the strength of the steel plate increases, the welded portion 116 becomes hard, and hydrogen embrittlement may occur in the welded portion 116 .

In addition, in the first comparative example, when the heating temperature of the plurality of point contact portions between the plurality of convex portions 115 and the first to-be-bonded portion 21 increases and the pressing time increases, the following occurs. That is, as the welded portion 116 becomes harder, the plurality of welded portions 116 formed at the plurality of point contact portions are more likely to be penetrated by hydrogen from the atmosphere or from the rust preventive oil on the surface of the first plate member 150 . Therefore, when the first plate material 150 is a high-strength steel plate, hydrogen embrittlement is likely to occur. In particular, the problem of hydrogen embrittlement becomes apparent in high-strength steel sheets exceeding 1.5 GPa class.

Here, in order to reduce the influence of hydrogen embrittlement, it is conceivable to reduce the size of the welded portion 116 . However, in this case, the peel strength of nut 110 is reduced. On the other hand, in order to improve the peel strength of nut 110, it is conceivable to increase the size of welded portion 116. FIG. However, in this case, the influence of hydrogen embrittlement increases. That is, there is a trade-off relationship between peel strength and hydrogen embrittlement.

On the other hand, in the first embodiment (see FIGS. 1A, 1B, 2A, and 2B), the fastening member 10 is pressurized while being energized and heated by the pair of electrodes 40, and the tip of the shaft portion 12 is crushed. . As a result, a crimped portion 15 is formed at the distal end portion of the shaft portion 12 so as to be crimped to the peripheral portion of the through hole 22 in the second plate surface 21B. The crimped portion 15 is formed in an annular shape along the circumferential direction of the shaft portion 12 and functions as a retaining portion that is hooked to the peripheral portion of the through hole 22 . Therefore, the first embodiment can increase the peel strength of the fastening member 10 compared to the projection welding according to the first comparative example. Further, since the first jointed portion 21 does not melt, even if the first plate material 20 including the first jointed portion 21 is a high-strength steel plate, the toughness of the first jointed portion 21 is less likely to decrease. That is, the first embodiment can obtain high effects even in high-strength steel sheets.

Further, in the first embodiment, the fastening member 10 is pressurized while being electrically heated by the pair of electrodes 40 at a heating temperature at which the first joined portion 21 is not melted. That is, in the first embodiment, the fastening member 10 is electrically heated and pressurized under the crimping condition in which the heating temperature of the first welded portion 21 is lower than that in projection welding. Therefore, since the first welded portion 21 does not melt, hydrogen embrittlement in the first welded portion 21 is suppressed. In particular, since the first embodiment can suppress hydrogen embrittlement in high-strength steel sheets exceeding 1.5 GPa class, high effects can be obtained in high-strength steel sheets.

Thus, the first embodiment can achieve both improvement in peel strength and suppression of hydrogen embrittlement.

(Comparison with second comparative example and third comparative example)
13A and 13B are diagrams showing a nut 120 and a joining joint according to a second comparative example. 13A is a vertical cross-sectional view of nut 120. FIG. FIG. 13B is a longitudinal cross-sectional view of a bonded joint.

A nut 120 according to a second comparative example is a pierce nut having an inner cylinder 122 and an outer wall 125 (outer cylinder) at one axial end of a nut body 121 . In this second comparative example, a nut 120 set on a plate member 150 is driven by a driving tool. As a result, a portion of the plate material 150 is punched out by the inner cylinder 122 and a hole 152 is formed in the plate material 150 . The nut 120 is fixed to the plate member 150 by inserting the inner cylinder 122 into the hole 152 and crimping the periphery of the hole 152 between the inner cylinder 122 and the outer wall 125 .

However, in the second comparative example, a screw hole 123 is formed from the nut body 121 to the inner cylinder 122 . Therefore, when part of the plate material 150 is punched out by the driven inner cylinder 122 of the nut 120 , the inner cylinder 122 may be deformed, and the screw hole 123 may be deformed along with the deformation of the inner cylinder 122 .

In addition, in the second comparative example, since the nut 120 is driven into the plate material 150 in the cold, it is difficult to apply to a high-strength steel plate.

14A and 14B are diagrams showing a nut 130 and a joining joint according to a third comparative example. 14A is a vertical cross-sectional view of nut 130. FIG. FIG. 14B is a longitudinal cross-sectional view of a bonded joint.

The nut 130 according to the third comparative example has the same configuration as the nut 120 according to the second comparative example (see FIGS. 13A and 13B), except that the outer wall 125 is a convex portion. In the third comparative example, the same reference numerals are used for the same configurations as in the second comparative example.

A screw hole 123 is also formed in the nut 130 according to the third comparative example from the nut body 121 to the inner cylinder 122 . Therefore, when part of the plate material 150 is punched out by the driven inner cylinder 122 of the nut 130 , the inner cylinder 122 may be deformed, and the screw hole 123 may be deformed along with the deformation of the inner cylinder 122 .

Also, in the third comparative example, since the nut 130 is driven into the plate material 150 in the cold, it is difficult to apply to a high-strength steel plate.

On the other hand, the fastening member 10 according to the first embodiment (see FIGS. 1A, 1B, 2A, and 2B) includes a flange 11 and a shaft portion 12 protruding from one end of the flange 11 in the axial direction. and The screw hole 13 of the fastening member 10 is not formed in the shaft portion 12 but is formed only in the flange 11 . Therefore, even if the tip of the shaft portion 12 is crushed to form the caulked portion 15 in the second step of the joint manufacturing method, deformation of the screw hole 13 is suppressed.

Further, in the first embodiment, since the fastening member 10 is fixed to the first plate material 20 by crushing the tip of the shaft portion 12, application to high-strength steel plates is possible.

(Comparison with the fourth comparative example)
15A and 15B are diagrams showing a method of manufacturing a joint according to the fourth comparative example. FIG. 15A is a diagram explaining the first step of the joint manufacturing method. FIG. 15B is a diagram explaining the second step of the joint manufacturing method.

In the fourth comparative example, a nut 140 having a flange portion 141 and a body portion 142, that is, a caulking nut is used. In this fourth comparative example, an annular caulking deformed portion 145 is formed in the body portion 142 by crushing the body portion 142 in the axial direction while the body portion 142 of the nut 140 is inserted into the hole 152 of the plate member 150. be done. The nut 140 is fixed to the plate member 150 in a state in which the plate member 150 is sandwiched between the flange portion 141 and the crimp deformation portion 145 of the nut 140 .

However, in this fourth comparative example, a threaded hole 143 is formed in the body portion 142 of the nut 140 . Since the crimping deformation portion 145 is adjacent to the screw hole 143 , there is a possibility that the screw hole 143 is deformed when the crimping deformation portion 145 is formed in the trunk portion 142 .

On the other hand, the fastening member 10 according to the first embodiment (see FIGS. 1A, 1B, 2A, and 2B) includes a flange 11 and a shaft portion 12 protruding from one end of the flange 11 in the axial direction. and The screw hole 13 of this fastening member 10 is not formed in the shaft portion 12 but is formed only in the flange 11 . Therefore, even if the tip of the shaft portion 12 is crushed to form the caulked portion 15 in the second step of the joint manufacturing method, deformation of the screw hole 13 is suppressed.

In particular, in the second step of the joint manufacturing method, the tip of the shank 12 to be crushed is located away from the flange 11 having the screw hole 13 . Therefore, in the first embodiment, deformation of the screw hole 13 is suppressed as compared with the case where the crimp deformation portion 145 is adjacent to the screw hole 13 as in the fourth comparative example (see FIGS. 15A and 15B). .

Next, examples will be described.

An example to which the first embodiment (see FIGS. 1A, 1B, 2A, 2B, 3A, and 3B) is applied and the first comparative example described above (FIGS. 11A, 11B, 12A, and 12B) is applied.

In the examples, a 1.5 GPa grade galvanized hot stamped steel sheet was used as the plate material. The plate thickness of the plate material is 2.0 mm. The shape of the fastening member used in the examples is as follows: the outer diameter of the female screw portion is 16 mm, the length of the female screw portion is 10 mm, the root diameter (inner diameter) of the screw hole is 6 mm (M6), and the length of the shaft portion is 8 mm. , the outer diameter of the shaft is 14 mm, the diameter of the through hole of the shaft is 8 mm, and the thickness of the shaft is 3 mm. In a comparative example, a square nut described in JIS B 1163 was used. A pair of electrodes used in the examples had a diameter of 16 mm, a flat tip, and were made of a Cu—Cr alloy. The same electrodes as in this example were used in the comparative example, which is projection welding.

In the example, a current corresponding to caulking was applied between the pair of electrodes. In the comparative example, a current corresponding to projection welding was passed between a pair of electrodes. In the example, the applied pressure was 3920 N, the energization time was 10 cycles, and the holding time was 10 cycles (1 cycle=1/60 second). In Comparative Example 1, the current flowing between the pair of electrodes was 10.0 kA, and in Comparative Example 2, the current flowing between the pair of electrodes was 13.0 kA.

Table 1 shows the results of Example, Comparative Example 1, and Comparative Example 2. Evaluation items were "peel strength of fastening member or nut" and "failure to screw in bolt". The peel strength of the fastening member or nut was evaluated according to JIS B 1196 Annex A. The screwing failure of the bolt was evaluated by whether or not the bolt could be screwed into the nut. The case where the bolt was screwed into the nut was evaluated as "no", and the case where the bolt could not be screwed into the nut was evaluated as "yes".

As shown in Table 1, in Comparative Example 1, there was no screwing failure of the bolt, but since the current flowing between the pair of electrodes was reduced, the diameter of the melted point contact portion became smaller, and the nut peeled off. decreased strength. In Comparative Example 2, although the peel strength of the nut was high, the current flowing between the pair of electrodes was increased, so that spatter was generated. As a result, the spatter adhered to the screw hole of the nut, and the screwing failure of the bolt was judged to be "yes". On the other hand, in the example, a high peel strength of the fastening member was obtained, and the screwing failure of the bolt was "absent". In addition, in Comparative Examples 1 and 2, hydrogen embrittlement cracking sometimes occurred when a steel sheet having a tensile strength of 2.0 GPa or more was used instead of the 1.5 GPa grade galvanized hot stamped steel sheet. On the other hand, in the example, when a steel sheet having a tensile strength of 2.0 GPa or more was used instead of the 1.5 GPa grade galvanized hot stamped steel sheet, hydrogen embrittlement cracking was not observed.

Next, a modified example of the first embodiment will be described.

In the first embodiment described above, as a preferred example, the first plate member 20 is a steel plate, and the fastening member 10 is made of metal. However, the first plate member 20 may be other than a steel plate. Moreover, the fastening member 10 may be made of a material other than metal.

Further, for example, the first plate member 20 and the fastening member 10 may be made of resin. When the first plate member 20 and the fastening member 10 are made of resin, instead of the pair of electrodes 40, for example, a pair of heating and pressurizing members having a heating function such as a heater are used to heat the fastening member 10. pressurize it.

Further, in the first embodiment, the second part to be joined 51 is superimposed on the second plate surface 21B of the first part to be joined 21, and the first part to be joined 21 and the second part to be joined are 51 are joined by the fastening member 10 and the bolt 60 . However, the second part to be joined 51 is superimposed on the first plate surface 21A of the first part to be joined 21, and the first part to be joined 21 and the second part to be joined 51 are connected to the fastening member 10 and the bolt. 60 may be joined.

Further, in the first embodiment described above, the positions of the boundary between the through hole 14 and the screw hole 13 and the boundary between the shaft portion 12 and the flange 11 coincide in the axial direction. However, the axial position of the boundary between the through hole 14 and the screw hole 13 and the boundary between the shaft portion 12 and the flange 11 may be offset by the thickness of the first plate member 20, for example.

[Second embodiment]
Next, a second embodiment will be described.

4A and 4B are diagrams illustrating a method for manufacturing a joint according to the second embodiment. FIG. 4A is a diagram explaining the first step of the joint manufacturing method. FIG. 4B is a diagram for explaining the second step of the joint manufacturing method.

In the second embodiment, the configuration of the first joined portion 21 is changed as follows from the above-described first embodiment. That is, the first joined portion 21 has a bulging portion 23 . The bulging portion 23 bulges toward the first plate surface 21A with respect to the flat portion 24 of the first plate member 20 . A through hole 22 is formed at the top of the bulging portion 23 . The bulging portion 23 has an inner diameter that does not interfere with the electrode 40 . The bulging portion 23 can be produced, for example, by press molding.

In the joint manufacturing method according to the second embodiment, as in the first embodiment, the shaft portion 12 of the fastening member 10 is passed through the through hole 22 in the first step, and the fastening member is inserted by the pair of electrodes 40 in the second step. 10 is pressurized while being energized and heated.

However, in the joint manufacturing method according to the second embodiment, in the second step, the fastening member 10 is pressurized while being electrically heated by the pair of electrodes 40 . As a result, the protrusion height h2 of the tip of the shaft portion 12 with respect to the top of the bulging portion 23 is equal to the height h1 of the step formed between the top of the bulging portion 23 and the flat portion 24 on the second plate surface 21B. The tip of the shaft portion 12 is crushed so as to be lower than the . That is, in the second step, the tip of the shaft portion 12 is crushed so that the shaft portion 12 is accommodated in the bulging portion 23 by pressurizing the fastening member 10 while being electrically heated by the pair of electrodes 40 . This prevents the tip of the shaft portion 12 from protruding beyond the flat portion 24 .

FIG. 5A and FIG. 5B are diagrams for explaining the plate material joining method according to the second embodiment. FIG. 5A is a diagram for explaining the first step of the method for joining plate materials. FIG. 5B is a diagram for explaining the second step of the method for joining plate materials.

As an example, the second joined portion 51 is formed flat. Then, in the plate member joining method according to the second embodiment, the male threaded portion 63 of the bolt 60 is passed through the through hole 52 from the second joined portion 51 side, as in the first embodiment. Then, by screwing the male threaded portion 63 of the bolt 60 into the screw hole 13 of the fastening member 10, the first joined portion 21 and the second joined portion 51 are joined.

According to the second embodiment, the projection height h2 of the tip of the shaft portion 12 with respect to the top of the bulging portion 23 is formed between the top of the bulging portion 23 and the flat portion 24 on the second plate surface 21B. It is lower than the step height h1. Therefore, the tip of the shaft portion 12 is suppressed from protruding beyond the flat portion 24 . Therefore, the tip of the shaft portion 12 is prevented from interfering with the second joined portion 51, so that the second joined portion 51 can be made flat. Thereby, the flexibility of the shape of the second plate member 50 including the second to-be-joined portion 51 can be improved.

[Third Embodiment]
Next, a third embodiment will be described.

6A and 6B are diagrams showing the fastening member 10 according to the third embodiment. 6A is a front view of the fastening member 10. FIG. 6B is a vertical cross-sectional view of the fastening member 10. FIG.

In the third embodiment, the configuration of the fastening member 10 is changed as follows with respect to the above-described first embodiment. That is, the shaft portion 12 is a male screw having threads on its outer peripheral surface. The configuration other than the thread formed on the outer peripheral surface of the shaft portion 12 is the same as that of the above-described first embodiment.

7A and 7B are diagrams illustrating a method for manufacturing a joint according to the third embodiment. FIG. 7A is a diagram explaining the first step of the joint manufacturing method. FIG. 7B is a diagram for explaining the second step of the joint manufacturing method.

In the third embodiment, the configuration of the first joined portion 21 is changed as follows from the above-described first embodiment. That is, the through hole 22 formed in the first joined portion 21 is a screw hole having a screw groove on the inner peripheral surface. The configuration other than the screw holes formed on the inner peripheral surface of the through hole 22 is the same as that of the above-described first embodiment.

In the method for manufacturing a joint according to the third embodiment, in the first step, the shaft portion 12, which is a male screw, is screwed into the through hole 22, which is a screw hole. At this time, the flange 11 abuts on the peripheral portion of the through hole 22 in the first plate surface 21A, and the tip of the shaft portion 12 protrudes from the second plate surface 21B of the first joined portion 21 with the male screw. A shaft portion 12 is screwed into a through hole 22 which is a screw hole.

Next, in the second step, the fastening member 10 is pressurized while being electrically heated by the pair of electrodes 40 . At this time, forming the caulked portion 15 that is crimped to the peripheral portion of the through hole 22 in the second plate surface 21B at the tip of the shaft portion 12 is the same as in the first embodiment. As a result, the fastening member 10 is fixed to the first jointed portion 21 with the first jointed portion 21 sandwiched between the flange 11 and the crimped portion 15 .

FIG. 8A and FIG. 8B are diagrams for explaining the plate material joining method according to the third embodiment. FIG. 8A is a diagram for explaining the first step of the method for joining plate materials. FIG. 8B is a diagram for explaining the second step of the method for joining plate materials.

In the plate member joining method according to the third embodiment, the male threaded portion 63 of the bolt 60 is passed through the through hole 52 from the second joined portion 51 side, as in the first embodiment. By screwing the male threaded portion 63 into the screw hole 13 of the fastening member 10, the first joined portion 21 and the second joined portion 51 are joined.

According to the third embodiment, the shaft portion 12 is a male thread. Also, the through hole 22 is a screw hole. The shaft portion 12, which is a male screw, is screwed into a through hole 22, which is a screw hole. Further, in the fastening member 10 in which the crimped portion 15 is formed at the tip of the shaft portion 12 , the first joint portion 21 extends from both sides of the first joint portion 21 in the plate thickness direction to the flange 11 and the crimped portion 15 . It will be sandwiched by the caulked portion 15 . Therefore, the fastening member 10 is suppressed from rotating with respect to the first joined portion 21 .

In other words, when a rotational force acts on the fastening member 10 , the rotational force acting on the fastening member 10 is transferred to the shaft of the fastening member 10 due to the screw structure of the shaft portion 12 that is a male screw and the through hole 22 that is a screw hole. converted to force. However, by sandwiching the first joined portion 21 between the flange 11 and the caulked portion 15, the axial movement of the fastening member 10 is restrained. When the axial movement of the fastening member 10 is restricted by the flange 11 and the caulked portion 15 in this way, the rotation of the fastening member 10 is also restricted. As a result, the fastening member 10 is prevented from rotating with respect to the first joined portion 21 .

[Fourth embodiment]
Next, a fourth embodiment of the invention will be described.

FIG. 9 is an exploded perspective view of the joining joint 30 according to the fourth embodiment. In the fourth embodiment, the configurations of the fastening member 10 and the first joined portion 21 are changed as follows from the above-described first embodiment.

That is, the shaft portion 12 is a polygonal tube. Also, the through hole 22 is a polygonal hole. The outer peripheral shape of the shaft portion 12 and the inner peripheral shape of the through hole 22 are, for example, regular hexagons, but may be polygonal shapes other than regular hexagons. Moreover, the polygonal shape may be different between the shaft portion 12 and the through hole 22 . The shaft portion 12 is engaged with the through hole 22 . That is, the shaft portion 12 is fixed to the through hole 22 so as not to be rotatable about the axis.

In the fourth embodiment, configurations other than the above are the same as those in the first embodiment. In addition, in the fourth embodiment, the joint manufacturing method and the plate member joining method are the same as those in the first embodiment.

In the fourth embodiment, the shaft portion 12, which is a polygonal tube, is engaged with the through hole 22, which is a polygonal hole, thereby preventing the fastening member 10 from rotating with respect to the first joined portion 21. be able to.

In addition, the through hole 22 is desirably less than octagonal. This is because as the number of corners of the through hole 22 increases, the through hole 22 approaches a circular shape and the effect of suppressing the rotation of the fastening member 10 decreases.

Further, in the fourth embodiment, the shaft portion 12, which is a polygonal tube, is passed through the through hole 22, which is a polygonal hole. However, for example, the shaft portion 12, which is a cylinder, may be passed through the through hole 22, which is a polygonal hole. In this case, when the tip of the shaft portion 12 is crushed by the pair of electrodes 40 to form the caulked portion 15 , the diameter of the shaft portion 12 expands in the through hole 22 and is engaged with the inner peripheral surface of the through hole 22 . be. Thereby, the fastening member 10 can be prevented from rotating with respect to the first plate member 20 .

[Fifth embodiment]
Next, a fifth embodiment of the invention will be described.

10A and 10B are diagrams illustrating a method for manufacturing a joint according to the fifth embodiment. FIG. 10A is a diagram explaining the first step of the joint manufacturing method. FIG. 10B is a diagram explaining the second step of the joint manufacturing method.

In the fifth embodiment, a plurality of first plate members 20 are stacked. Also, a first joint portion 21 is formed on each of the plurality of first plate members 20 . By fixing the fastening member 10 to the plurality of first to-be-joined portions 21 that are overlapped, the joint 30 including the plurality of first to-be-joined portions 21 and the fastening member 10 is manufactured.

At least one of the plurality of first plate members 20 is a steel plate with a tensile strength of 780 MPa or more, preferably a steel plate with a tensile strength of 980 MPa or more. Further, the plate thickness of the steel plate is, for example, 0.5 mm to 4.0 mm. At least one of the plurality of first plate members 20 may be a surface-treated steel plate.

Even when the fastening member 10 is fixed to a plurality of first joined portions 21 that are overlapped as in the fifth embodiment, the same functions and effects as in the first embodiment can be obtained.

The first to fifth embodiments have been described above. However, the technology disclosed by the present application is not limited to the above-described first to fifth embodiments, and can of course be modified in various ways without departing from the gist thereof.

In addition, among the first to fifth embodiments, the combinable embodiments may be combined as appropriate.

In addition, the disclosure of Japanese Patent Application No. 2020-115833 filed on July 3, 2020 is incorporated herein by reference in its entirety.
All publications, patent applications and technical standards mentioned herein are to the same extent as if each individual publication, patent application and technical standard were specifically and individually noted to be incorporated by reference. incorporated herein by reference.

In addition, the following additional remarks are disclosed regarding the above embodiment.

(Appendix 1)
In a method for manufacturing a bonded joint, wherein a nut is fixed to a joint formed in a plate material to obtain a bonded joint including the joint and the nut,
The nut includes a female screw portion having a screw hole, and a shaft portion having a through hole formed coaxially with the screw hole and protruding from one axial end of the female screw portion, an outer diameter of the female thread portion is larger than an outer diameter of the shaft portion, and a wall thickness of the female thread portion is thicker than the wall thickness of the shaft portion;
As a step of fixing the nut to the joint,
The shaft portion is inserted through a through hole formed in the joint portion so that the female screw portion is brought into contact with the first plate surface of the joint portion, and the distal end portion of the shaft portion is inserted into the second plate surface of the joint portion. A first step of protruding from the plate surface;
In a state in which the nut is sandwiched between a pair of heating and pressurizing members from both sides in the axial direction of the nut, the nut is heated and pressurized by the pair of heating and pressurizing members, thereby crimping the tip portion of the shaft portion, a second step of forming a crimped portion that engages with a peripheral portion of the through hole on the second plate surface at the tip portion of the shaft portion;
A method of manufacturing a joint joint comprising:
(Appendix 2)
the through hole is a screw hole,
The shaft portion is a male screw,
In the first step, screwing the shaft portion into the through hole,
A method for manufacturing a bonded joint according to appendix 1.
(Appendix 3)
the through hole is a polygonal hole,
The shaft portion is a polygonal cylinder,
In the first step, engaging the shaft with the through hole;
A method for manufacturing a bonded joint according to appendix 1.
(Appendix 4)
The joint portion has a bulging portion that bulges toward the first plate surface with respect to a flat portion formed on the plate material and that has the through hole formed at the top thereof.
A method for manufacturing a joint joint according to any one of appendices 1 to 3.
(Appendix 5)
In the second step, by heating and pressurizing the nut with the pair of heating and pressurizing members, the projection height of the tip portion of the shaft portion with respect to the top portion of the bulging portion is adjusted to the top portion of the bulging portion. crimping the tip portion of the shaft portion so that the height between the flat portion and the flat portion is lower than the height of the step formed on the second plate surface;
A method for manufacturing a bonded joint according to appendix 4.
(Appendix 6)
The nut is made of metal,
The plate material is a steel plate having a tensile strength of 780 MPa or more,
The heating and pressurizing member is an electrode,
A method for manufacturing a joint joint according to any one of appendices 1 to 5.
(Appendix 7)
A second plate material different from the first plate material as the plate material is added to the first joint portion as the joint portion in the joined joint manufactured by the method for manufacturing a joint joint according to any one of Appendixes 1 to 6. Overlapping the second joint formed on the plate material,
A threaded portion of a bolt is inserted through an insertion hole formed in the second joint portion, and the threaded portion is screwed into the threaded hole of the nut to join the first joint portion and the second joint portion. do,
A plate joining method comprising:
(Appendix 8)
A joint joint comprising a joint formed in a plate material and a nut joined to the joint,
The nut includes a female screw portion having a screw hole, and a shaft portion having a through hole formed coaxially with the screw hole and protruding from one axial end of the female screw portion, an outer diameter of the female thread portion is larger than an outer diameter of the shaft portion, and a wall thickness of the female thread portion is thicker than the wall thickness of the shaft portion;
The shaft portion is inserted through a through hole formed in the joint portion,
The female screw portion abuts on the first plate surface of the joint portion,
a tip portion of the shaft portion protrudes from a second plate surface of the joint portion;
A crimped portion is formed at a tip portion of the shaft portion and is engaged with a peripheral portion of the through hole on the second plate surface,
joint joint.
(Appendix 9)
the through hole is a screw hole,
The shaft portion is a male screw and is screwed into the through hole,
The joint joint according to appendix 8.
(Appendix 10)
the through hole is a polygonal hole,
The shaft portion is a polygonal tube and is engaged with the through hole,
The joint joint according to appendix 8.
(Appendix 11)
The joint portion has a bulging portion that bulges toward the first plate surface with respect to a flat portion formed on the plate material and that has the through hole formed at the top thereof.
The joining joint according to any one of appendices 8 to 10.
(Appendix 12)
The projection height of the tip of the shaft with respect to the top of the bulging portion is lower than the height of the step formed on the second plate surface between the top of the bulging portion and the flat portion,
11. The joint joint according to Appendix 10.
(Appendix 13)
The nut is made of metal,
The plate material is a steel plate having a tensile strength of 780 MPa or more,
The joining joint according to any one of appendices 8 to 12.
(Appendix 14)
An automobile part comprising the joint according to any one of appendices 8 to 13.
(Appendix 15)
The joining joint according to any one of appendices 8 to 13;
a second joint portion formed on a second plate material different from the first plate material as the plate material and superimposed on the first joint portion as the joint portion;
A bolt that joins the first joint portion and the second joint portion by inserting a screw portion into an insertion hole formed in the second joint portion and screwing the screw portion into the screw hole of the nut. and,
A plate material joining structure.
(Appendix 16)
An automobile part comprising the plate material joining structure according to appendix 15.
(Appendix 17)
a female threaded portion having a screw hole;
a shaft portion having a through hole formed coaxially with the screw hole and protruding from one axial end of the female thread portion;
with
The outer diameter of the female threaded portion is greater than the outer diameter of the shaft portion, and the thickness of the female threaded portion is greater than the thickness of the shaft portion.
nut.
(Appendix 18)
The shaft portion is a male screw,
A nut according to Appendix 17.
(Appendix 19)
The shaft portion is a polygonal tube,
A nut according to Appendix 17.

Claims (11)

A fastening member comprising a shaft and a flange provided at an axial end of the shaft,
The fastening member has a first through hole penetrating the shaft portion and the flange along the axial direction of the shaft portion,
The first through hole in the flange is a screw hole,
The diameter of the first through hole in the cross section of the shaft portion is larger than the root diameter of the screw hole in the cross section of the flange,
A method for manufacturing a joint for fixing the fastening member to a first plate having a second through hole ,
passing the shaft portion of the fastening member through the second through hole of the first plate;
abutting the flange against the first plate;
The tip of the shaft portion is crushed to widen the shaft portion radially outward to caulk the first plate material, and the first through hole in the shaft portion is formed when viewed along the axial direction of the shaft portion. extending the shaft portion radially inward from the edge;
A method of manufacturing a joint comprising: The outer diameter of the flange is larger than the outer diameter of the shaft,
the thickness of the flange is greater than the thickness of the shaft;
A method for manufacturing a joint according to claim 1. The shaft portion is a male screw,
A method for manufacturing a joint according to claim 1 or 2. A fastening member comprising a shaft and a flange provided at an axial end of the shaft,
The fastening member has a first through hole penetrating the shaft portion and the flange along the axial direction of the shaft portion,
The first through hole in the flange is a screw hole,
The diameter of the first through hole in the cross section of the shaft portion is larger than the root diameter of the screw hole in the cross section of the flange,
A method for manufacturing a joint for fixing the fastening member to a first plate having a second through hole,
passing the shaft portion of the fastening member through the second through hole of the first plate;
abutting the flange against the first plate;
crimping the first plate by crushing the tip of the shaft;
with
The second through hole is a screw hole,
The shaft portion is a male screw,
screwing the shaft into the second through hole;
Method for manufacturing fittings. The second through hole is a polygonal hole,
engaging the shaft with the second through hole;
A method for manufacturing a joint according to any one of claims 1 to 3. In a state in which the fastening member is sandwiched between a pair of heating and pressurizing members from both sides in the axial direction, the fastening member is heated by the pair of heating and pressurizing members and pressurized in the axial direction of the fastening member, whereby the shaft portion crimping the first plate material by crushing the tip of
A method for manufacturing a joint according to any one of claims 1 to 5. The fastening member is made of metal,
The first plate material is a steel plate having a tensile strength of 780 MPa or more,
The pair of heating and pressurizing members are a pair of electrodes,
A method for manufacturing a joint according to claim 6. passing the male screw portion of the screw member through the third through-hole of the second plate having the third through-hole;
passing the male threaded portion through the first through hole of the shaft;
fixing the second plate member by screwing the male screw portion into the screw hole;
A method for manufacturing a joint according to any one of claims 1 to 7. The first plate member bulges to the side opposite to the second plate member and has a bulging portion with the second through hole at the top,
A method for manufacturing a joint according to claim 8. a plate with a second through hole;
A fastening system comprising a shaft portion and a flange provided at an axial end portion of the shaft portion, wherein the flange is in contact with the plate member while the shaft portion is passed through the second through hole. a member;
with
The fastening member has a first through hole penetrating the shaft portion and the flange along the axial direction of the shaft portion,
The first through hole in the flange is a screw hole,
The diameter of the first through hole in the cross section of the shaft portion is larger than the root diameter of the screw hole in the cross section of the flange,
At the tip of the shaft protruding from the second through hole, there is a crimping portion that expands radially outward of the shaft and crimps the plate material together with the flange, an extending portion extending radially inward of the shaft portion from the edge of the first through hole in the shaft portion;
fittings. A motor vehicle part comprising a joint according to claim 10.