JP6773094B2 - Joining device and joining method for metal members - Google Patents

Description

The present invention relates to a joining device and a joining method for metal members, and more particularly to a technique for joining dissimilar metals using resistance welding.

As a method of joining a rod-shaped or tubular first metal member and an annular second metal member, a joining method is used in which a large current is applied in a short time while press-fitting into one of the holes. There is. Specifically, first, the size of the first metal member in the cross section is made larger than the size of the hole in the second metal member in the cross section. Further, the tip portion of the first metal member is tapered, and the opening edge of the hole portion of the second metal member is also tapered.

Next, the first metal member is addressed to the hole of the second metal member, and a large current is passed in a short time while pressurizing. As a result, the outer peripheral surface of the first metal member and one interface portion of the second metal member are softened and plastically flowed, and solid-phase bonding is performed at the interface portion.

In the above joining method, a large current is applied in a short time, so that the joining portion and its surroundings are less likely to be burnt or distorted, and high-precision joining is possible. In addition, it is possible to reduce costs as compared with joining using arc welding or brazing.

By the way, in recent years, in order to reduce the weight and cost, technical development for joining dissimilar metals having different physical properties (melting temperature, proof stress, etc.) has been made (Patent Document 1).

Japanese Unexamined Patent Publication No. 2006-181627

However, when dissimilar metals having different physical properties from each other are to be joined by the above-mentioned joining method according to the prior art, it is necessary to take a large amount of upset in order to secure the joining strength. This leads to an increase in the size and weight of the joined parts.

Regarding this, the matters examined by the present inventors will be described with reference to FIG. FIG. 10 shows a state in which the first metal member 900 made of carbon steel and the second metal member 901 made of an aluminum alloy (Al alloy) are joined by using the joining method as described above. As shown in FIG. 10, in the joining method, the tapered surface 900a of the first metal member 900 is pressed (arrow A ₉₀ ) against the tapered surface 901b of the second metal member 901 to plastically flow, and the diffusion layer 902 is formed. Solid phase bonding.

However, since the melting temperature of the second metal member 901 made of Al alloy is lower than that of carbon steel, the Al alloy at the initial stage of joining melts and becomes burrs 903 and is discharged to the outside. As a result, an unjoined portion Ar ₀ is generated. Further, the second metal member 901 is deformed due to the difference in yield strength between the Al alloy and the carbon steel. From these, in the prior art, it was necessary to take a large amount of upset in order to secure the joint strength.

The present invention has been made to solve the above problems, and provides a joining device and joining method for metal members capable of suppressing an increase in the amount of upset while ensuring high joining strength. The purpose is to do.

The metal member joining device according to one aspect of the present invention is the metal member joining device for joining a rod-shaped or tubular first metal member by press-fitting it into a hole of an annular second metal member. The first metal member is made of a first metal material, the second metal member is made of a second metal material different from the first metal material, and the size of the hole in the cross section is the first. It is smaller than the size in the cross section of the metal member, and the joining device for the metal member has a table on which the second metal member is placed and a table on which the second metal member is placed. In this state, the first metal member is pressed toward the hole of the second metal member and press-fitted, and a welding current is applied between the first metal member and the second metal member. Crosses the press-fitting direction with respect to the current supply means for supplying the metal and the member of the first metal member and the second metal member on which at least one of the strength and melting temperature of the constituent metal material is lower. A deformation suppressing means for suppressing deformation in the cross-sectional direction, which is the direction in which the metal is formed, is provided, and the deformation suppressing means is provided in a region including at least a plastic flow range in the press-fitting direction. The metal material has a lower resistance and melting temperature than the first metal material, and the deformation suppressing means refers to the second metal member from the outer peripheral portion of the second metal member in the cross-sectional direction. A tightening load is applied in the direction, and the deformation suppressing means attaches a plurality of deformation suppressing heads arranged along the outer peripheral portion of the second metal member and each of the plurality of deformation suppressing heads in the cross-sectional direction. The plurality of deformation suppressing heads have a pressing mechanism that presses inward, and the plurality of deformation suppressing heads are adjacent to each other in the outer peripheral direction of the second metal member, and receive pressing force from the pressing mechanism, and each of the outer peripheral heads receives the pressing force. The tightening load is applied so as to be in close contact with the portion without a gap, and the addition of the tightening load by the deformation suppressing means is performed by the pressurizing means for the first metal to the hole portion of the second metal member. It is done in synchronization with the press fitting of the member.

As described above, when the proof stress and melting temperature of the second metal material are lower than those of the first metal material, when the current is started to flow while pressurizing by the pressurizing means, the temperature rises and the cross section outwards. Due to the stress, both the inner and outer peripheral lengths of the second metal member tend to increase. That is, the diameter of the second metal member tries to increase.

However, in the metal member joining device according to this embodiment, since the second metal member is tightened from the outer peripheral portion thereof toward the inside in the cross-sectional direction by the deformation suppressing means, the expansion of the second metal member to the outside is suppressed. can do.

Further, in the metal member joining device according to this aspect, the deformation suppressing means includes a plurality of deformation suppressing heads and a pressing mechanism for pressing the heads. As a result, deformation of the second metal member can be suppressed without using a complicated mechanism.

Further, since the outer peripheral portion of the second metal member is pressed by using a plurality of deformation suppressing heads, the pressing with less bias is possible, and the spread of the second metal member to the outside in the cross-sectional direction is suppressed without bias. Can be done.
Further, in the metal member joining device according to the present embodiment, since the application of the tightening load and the press-fitting are executed in synchronization, the load for suppressing the deformation can be applied at an appropriate timing. Therefore, it is possible to efficiently suppress an increase in the amount of upset while ensuring high bonding strength.

As a specific example of the "pressing mechanism", a pneumatic cylinder, a hydraulic cylinder, an electric motor, or the like can be adopted, or manually (more specifically, for example, a collet chuck) via a link mechanism or the like. It can also be pressed (with the configuration used).

In addition, the "plastic flow range" can be set experimentally and empirically based on the physical properties of the first metal material and the second metal material, the joining conditions, the environmental conditions, and the like.

Further, as the current supply means, a known current supply device for a metal member joining device (capacitor welding device) can be adopted. Specifically, it is equipped with an electrolytic capacitor, a welding transformer, a discharge circuit, and a large current circuit. The electrolytic capacitor is once charged with the electrical energy required for welding, and this is discharged to the transformer in a short time to generate a large current in a short time. It is a device that supplies between the first metal member and the second metal member.

Therefore, in the metal member joining device according to this embodiment, even when the second metal member is made of a material having a relatively low proof stress and melting temperature, the upset amount is increased while ensuring high joining strength. Can be suppressed.

In the metal member joining apparatus according to the above aspect, the second metal material may be a material containing aluminum, and the first metal material may be a material containing iron.

In the above metal member joining device, even when joining aluminum-based materials (materials containing aluminum) and iron-based materials (materials containing iron), which have different yield strengths and melting temperatures, while ensuring high joining strength, it is improved. It is possible to suppress an increase in the set amount.

The method for joining a metal member according to one aspect of the present invention is a method for joining a metal member by press-fitting a rod-shaped or tubular first metal member into a hole of an annular second metal member. It is composed of a first metal member preparation step for preparing the first metal member made of one metal material and a second metal material different from the first metal material, and the cross-sectional size of the hole is of the first metal member. A second metal member preparation step for preparing the second metal member set smaller than the cross-sectional size, a mounting step for mounting the second metal member on a table, and the first on the table. A pressurizing step of pressurizing and press-fitting the first metal member toward the hole of the second metal member while the two metal members are placed, and the first metal member and the second metal. The current supply step for supplying a welding current between the members and the member of the first metal member and the second metal member on which at least one of the strength and melting temperature of the constituent metal material is lower is crossed. A deformation suppressing step for suppressing deformation in the plane direction is provided, and in the deformation suppressing step, deformation is suppressed at least in a region including a plastic flow range in the press-fitting direction, and the second metal material is the same. The resistance and melting temperature are lower than those of the first metal material, and in the deformation suppressing step, a plurality of deformation suppressing heads arranged along the outer peripheral portion of the second metal member and each of the plurality of deformation suppressing heads. The inward tightening load in the cross-sectional direction is applied by using a pressing mechanism that presses the metal inward in the cross-sectional direction, and the plurality of deformation suppressing heads are mutually used in the outer peripheral direction of the second metal member. The tightening load is applied so that each of them is in contact with the outer peripheral portion without a gap in response to the pressing force from the pressing mechanism, and the tightening load is applied in the deformation suppressing step. This is done in synchronization with the press-fitting of the first metal member into the hole of the second metal material in the pressurizing step.

In the method of joining metal members according to this aspect, as a specific execution method of the deformation suppressing step, a plurality of deformation suppressing heads are pressed by a pressing mechanism. As a result, it is possible to suppress the deformation of the second metal member while suppressing the variation of the applied pressing force in each region of the outer peripheral portion.

Further, since the outer peripheral portion of the second metal member is pressed by using a plurality of deformation suppressing heads, the pressing with less bias is possible, and the expansion (diameter expansion) of the second metal member to the outside in the cross-sectional direction is biased. Can be suppressed without.
Further, in the metal member joining device according to the present embodiment, since the application of the tightening load and the press-fitting are executed in synchronization, the load for suppressing the deformation can be applied at an appropriate timing. Therefore, it is possible to efficiently suppress an increase in the amount of upset while ensuring high bonding strength.

The pressing mechanism and the plastic flow range are the same as above.

In the method for joining metal members according to the above aspect, the second metal material may be a material containing aluminum, and the first metal material may be a material containing iron.

In the above method of joining metal members, even when joining aluminum-based materials (materials containing aluminum) and iron-based materials (materials containing iron), which have different yield strengths and melting temperatures, while ensuring high joining strength, it is improved. It is possible to suppress an increase in the set amount.

In each of the above aspects, an increase in the amount of upset can be suppressed while ensuring high bonding strength.

It is a schematic cross-sectional view which shows the structure of the metal member joining apparatus 1 which concerns on 1st Embodiment of this invention. It is a schematic plan view which shows the structure of the deformation suppressing unit 17 in a metal member joining apparatus 1. FIG. It is a schematic diagram for demonstrating the function performed by the deformation suppression unit 17. It is a schematic cross-sectional view which shows the 1st metal member 100 and the 2nd metal member 101 which were joined using the metal member joining apparatus 1. It is a schematic cross-sectional view which shows the structure of the metal member joining apparatus 2 which concerns on 2nd Embodiment of this invention. It is a schematic plan view which shows the structure of the deformation suppression unit 20 in a metal member joining apparatus 2. It is a schematic cross-sectional view which shows the 1st metal member 103 and the 2nd metal member 104 which were joined using the metal member joining apparatus 2. It is a schematic plan view showing the structure of the deformation suppressing unit 30 extracted from the structure of the metal member joining device which concerns on 3rd Embodiment of this invention. It is a schematic plan view which shows the structure of the deformation suppressing unit 40 extracted from the structure of the metal member joining apparatus which concerns on 4th Embodiment of this invention. It is a schematic cross-sectional view which shows the 1st metal member 900 and the 2nd metal member 901 which were joined using the metal member joining apparatus which concerns on the prior art.

Hereinafter, embodiments of the present invention will be described with reference to the drawings. The form described below is an aspect of the present invention, and the present invention is not limited to any of the following forms except for its essential configuration.

[First Embodiment]
1. 1. Configuration of Metal Member Joining Device 1 The configuration of the metal member joining device 1 according to the first embodiment of the present invention will be described with reference to FIG.

As shown in FIG. 1, the metal member joining device 1 according to the present embodiment includes a base 10, a welding head 11, a pressure rod 12, a deformation suppressing unit 17, and a welding current supply unit 18. The base 10 has a trapezoidal shape. The second metal member 101 is placed on the upper surface 10a of the base 10.

Welding head 11 is joined to the pressure rod 12, as shown by the arrow A _1, it has to be lowered in the Z axis direction. The first metal member 100 is held by the welding head 11. Here, of course, it is also possible to set the first metal member 100 in a state of being placed on the second metal member 101, and lower the welding head 11 to pressurize the first metal member 100.

Although not shown, the pressurizing rod 12 is connected to the pressurizing mechanism and can move up and down in the Z-axis direction as the pressurizing mechanism is driven. Specific examples of the pressurizing mechanism include a pneumatic cylinder, a hydraulic cylinder, an electric motor, and the like.

The deformation suppressing unit 17 has a pair of deformation suppressing heads 13 and 14, and pressing rods 15 and 16 joined to the deformation suppressing heads 13 and 14. The deformation suppressing heads 13 and 14 are arranged in a state of surrounding the outer peripheral portion of the second metal member 101 placed on the upper surface 10a of the base 10. The outer peripheral portion of the second metal member 101 and the inner peripheral portions of the deformation suppressing heads 13 and 14 are in close contact with each other with substantially no gap.

The deformation suppressing heads 13 and 14 receive the pressing force via the pressing rods 15 and 16 and, as shown by arrows A ₂ and A ₃ , the outer peripheral portion of the second metal member 101 is directed inward in the cross-sectional direction. It can be pressed. Although not shown, a pressing mechanism is connected to the pressing rods 15 and 16, so that the pressing mechanism can move forward and backward in the X direction as the pressing mechanism is driven. Specific examples of the pressing mechanism include a pneumatic cylinder, a hydraulic cylinder, an electric motor, and the like.

In the above, the "cross-sectional direction" is a direction orthogonal to the press-fitting direction of the first metal member 100 with respect to the hole 101a of the second metal member 101 (a plane direction orthogonal to the Z direction). .. The same applies to other parts of the present disclosure.

Here, the pressing by the deformation suppressing heads 13 and 14 is performed in synchronization with the pressurization of the welding head 11. More specifically, the welding head 11 is lowered as indicated by the arrow A _1, the tip of the first metal member 100 is in response to a timing to start pressed into the hole 101a of the second metal member 101 (synchronized ), deformation suppressing head 13 and 14, as indicated by the arrow _a 2, _{a 3,} begins to press the outer peripheral portion of the second metal member 101.

The pressing force and pressing stroke of the deformation suppressing heads 13 and 14 are controlled to such an extent that the outer peripheral portion of the second metal member 101 does not shrink more than a predetermined diameter.

The welding current supply unit 18 supplies a large current between the first metal member 100 and the second metal member 101 in a short time. In FIG. 1, the wiring is shown so as to be directly connected from the welding current supply unit 18 to the first metal member 100 and the second metal member 101, but the actual wiring form is limited to this. Not done. For example, the base 10 and the welding head 11 may be made of a conductive material so that the current is supplied from the welding current supply unit 18 through the base 10 and the welding head 11.

Specifically, as the welding current supply unit 18, a large current supply device having a configuration including an electrolytic capacitor, a welding transformer, a discharge circuit, and a large current circuit can be adopted. The welding current supply unit 18 temporarily charges the electrolytic capacitor with the electric energy required for welding, discharges the electric energy to the transformer in a short time, and supplies a large current to the first metal member 100 and the second metal member 101 in a short time. It is a device to supply in between.

2. First metal member 100 and second metal member 101 to be joined
Subsequently, with reference to FIG. 1, the first metal member 100 and the second metal member 101 to be joined will be described.

As shown in FIG. 1, the first metal member 100 has a solid rod shape. The first metal member 100 is arranged so that its axis is along the Z direction.

The lower end of the first metal member 100 in the Z direction, that is, the outer peripheral surface of the second metal member 101 on the press-fitting end side into the hole 101a is the tapered portion 100a.

Further, the cross-sectional diameter of the first metal member 100 is larger than the hole diameter of the hole 101a of the second metal member 101.

The constituent metal material of the first metal member 100 is a metal material containing iron (Fe), specifically, carbon steel. In this embodiment, S35C is adopted as an example. The yield point (proof stress) of S35C is 305 (N / mm ² ) or more, and the melting temperature is 1538 (° C.). The coefficient of linear expansion is 11.7 (× 10 ⁻⁶ / ° C.).

On the other hand, the second metal member 101 has an annular shape and has a hole portion 101a having a diameter smaller than the cross-sectional diameter of the first metal member 100. In the second metal member 101, the press-fit side rim of the hole 101a is a tapered portion 101b. The taper angle of the tapered portion 101b is substantially the same as the taper angle of the tapered portion 100a of the first metal member 100.

The second metal member 101 is made of a metal material containing aluminum (Al), specifically, an aluminum alloy. In this embodiment, A5056 (H34), which is an Al—Mg-based aluminum alloy, is adopted as an example. The yield point (proof stress) of A5056 (H34) is 230 (N / mm ² ), and the melting temperature is 568 to 638 (° C.). The coefficient of linear expansion is 26.3 (× 10 ^-6 / ° C.).

3. 3. Configuration of Deformation Suppression Unit 17 The configuration of the deformation suppression unit 17 included in the metal member joining device 1 according to the present embodiment will be supplementarily described with reference to FIG. FIG. 2 is a schematic plan view of the deformation suppressing unit 17 viewed from above in the Z direction of FIG.

As shown in FIG. 2, each of the deformation suppressing heads 13 and 14 in the deformation suppressing unit 17 has a semicircular ring shape. The deformation suppressing head 13 and the deformation suppressing head 14 are arranged so that their ends face each other.

With respect to the second metal member 101 having the hole 101a, the inner peripheral surfaces of the deformation suppressing heads 13 and 14 are aligned with the outer peripheral portion 101c without any gap. Between the second metal member 101 outer peripheral portion 101c with respect to the state of deformation suppression head 13, 14 abutted in, so that the drilled gaps _G 1, _{G 2.} The gaps G ₁ and G ₂ are minute gaps.

Here, what as the gap _G 1, _{G 2} are drilled between the second metal member 101 outer peripheral portion 101c with respect to the state of deformation suppression head 13, 14 abutted the second metal member 101 This is so that the deformation of the second metal member 101 can be suppressed even if there is a dimensional tolerance of the above and the dimensional tolerances of the deformation suppressing heads 13 and 14.

4. Joining the first metal member 100 and the second metal member 101 using the metal member joining device 1 Joining the first metal member 100 and the second metal member 101 using the metal member joining device 1 having the above configuration. Is done as follows.

(I) The first metal member 100 is prepared and set on the welding head 11. As shown in FIG. 1, when setting the first metal member 100 on the welding head 11, the tapered portion 100a is set on the outer periphery of the tip so that the tapered portion 100a faces the base 10.

(Ii) The second metal member 101 is prepared and placed on the upper surface 10a of the base 10. At this time, when the second metal member 101 is placed, the side provided with the tapered portion 101b on the press-fitting side opening edge faces the welding head 11. Further, the position is adjusted so that the center of the hole 101a in the second metal member 101 coincides with the axis of the first metal member 100 set in the welding head 11.

(Iii) The deformation suppressing heads 13 and 14 of the deformation suppressing unit 17 are set on the outer peripheral portion 101c of the second metal member 101. At this stage, the deformation suppressing heads 13 and 14 are only set so that there is no gap with respect to the outer peripheral portion 101c of the second metal member 101, and no inward pressing force in the radial direction is applied. ..

(Iv) a welding head 11 as shown by arrow _{A 1,} Yuku is lowered.

(V) When the tip of the first metal member 100 and the opening edge of the second metal member 101 facing the hole 101a are in contact with each other or in close proximity to each other, the current is supplied from the welding current supply unit 18. Start.

(Vi) When the tip of the first metal member 100 begins to press-fit into the hole 101a of the second metal member 101, the deformation suppressing heads 13 and 14 are indicated by arrows A ₂ and A ₃ together with the above current supply. As described above, the second metal member 101 is pressed inward in the radial direction. In other words, a tightening load is applied inward in the radial direction of the second metal member 101 in synchronization with the press fitting of the first metal member 100 into the hole 101a of the second metal member 101.

(Vii) The first metal member 100 is press-fitted by a predetermined amount of upset, and the joining is completed. Then, at the same time as the joining is completed or slightly later, the deformation suppressing operation by the deformation suppressing unit 17 is also completed.

5. Functions Performed by the Deformation Suppressing Unit 17 The functions performed by the deformation suppressing unit 17 in the metal member joining device 1 will be described with reference to FIGS. 3 and 4. FIG. 3 is a schematic view schematically showing the state of the second metal member 101 in a state where the first metal member 100 is press-fitted and a welding current is supplied. FIG. 4 is a schematic cross-sectional view showing the first metal member 100 and the second metal member 101 after joining using the metal member joining device 1.

As described above, the second metal member 101 is made of an aluminum alloy, and has a lower strength and melting temperature than the carbon steel constituting the first metal member 100. Therefore, as shown in FIG. 3, a force F ₁ that tends to deform outward in the radial direction acts on the second metal member 101. As a result, the peripheral lengths of the inner peripheral portion 101d and the outer peripheral portion 101c of the second metal member 101 tend to be extended.

However, in the present embodiment, the second metal member 101 is deformed suppressed head 13 and 14 contact the outer peripheral portion 101c on the deformation suppression unit 17, in synchronization with the fitting, a force in the radially inward F ₂ Is added. Therefore, in the second metal member 101, the outer diameter D ₂ hardly changes, and the inner diameter D ₁ does not change substantially except for the portion due to the plastic flow.

As described above, as shown in FIG. 4, the first metal member 100 and the second metal member 101 joined by using the metal member joining device 1 provided with the deformation suppressing unit 17 suppress the formation and discharge of burrs. Therefore, the occurrence of "unjoined portion" as shown in FIG. 10 is also suppressed. As a result, in the joining using the metal member joining device 1 according to the present embodiment, it is possible to form a long joining portion (diffusion layer 102) having a joining length of _{LB 102} while suppressing an increase in the amount of upset.

Therefore, in the joining using the metal member joining device 1 according to the present embodiment, the first metal member 100 and the second metal member 101 are joined with high joining strength while suppressing an increase in the upset amount. Can be done.

As shown in FIG. 4, in the metal member joining device 1 according to the present embodiment, the deformation suppressing heads 13 and 14 in the deformation suppressing unit 17 (in FIG. 4, only the deformation suppressing head 13 is shown) in the Z direction. The height H ₁₃ is equal to or higher than the height of the second metal member 101 in the Z direction. In other words, the lower surface 13b of the deformation suppressing heads 13 and 14 abuts on the upper surface 10a of the base 10, and the upper surface 13a is flush with or higher than the upper surface of the second metal member 101 in the Z direction. Is set to.

By setting the sizes and arrangements of the deformation suppressing heads 13 and 14 as described above, in the Z direction, a range including a range of plastic flow at the time of joining (a range substantially the same as the range in which the diffusion layer 102 is formed) is included. , A tightening load can be applied to the second metal member 101. As a result, deformation of the second metal member 101 in the diameter-expanding direction within the range where plastic flow occurs at the time of joining is reliably suppressed, and burr formation and discharge to the outside are suppressed.

6. Effect In the metal member joining device 1, a deformation suppressing unit 17 for suppressing deformation in the diameter-expanding direction is provided on the outer peripheral portion 101c of the second metal member 101, which has a lower yield strength and melting temperature of the constituent materials than the first metal member 100. Has been done. Therefore, it is possible to suppress the diameter-expanding deformation of the second metal member 101 after the first metal member 100 is press-fitted into the hole 101a of the second metal member 101 and the current starts to flow.

Further, since the deformation suppressing unit 17 is provided so as to be able to press the region including the plastic flow range, it is possible to effectively suppress the formation of burrs and the external discharge of burrs at the time of joining.

Therefore, in the metal member joining device 1 according to the present embodiment, in the joining of the first metal member 100 made of carbon steel and the second metal member 101 made of an aluminum alloy, the upset amount is increased while ensuring high joining strength. The increase can be suppressed.

Further, in the metal member joining device 1, the addition of the tightening load by the deformation suppressing unit 17 and the press-fitting of the first metal member 100 into the hole 101a by lowering the welding head 11 can be executed in synchronization with each other. , It is possible to apply a load to suppress deformation at an appropriate timing. Therefore, it is possible to efficiently suppress an increase in the amount of upset while ensuring high bonding strength.

Further, the deformation suppressing unit 17 in the metal member joining device 1 has two deformation suppressing heads 13 and 14. As a result, pressing with less bias is possible, and expansion deformation of the second metal member 101 in the cross-sectional direction can be suppressed without bias.

[Second Embodiment]
1. 1. Configuration of Metal Member Joining Device 2 The configuration of the metal member joining device 2 according to the second embodiment of the present invention will be described with reference to FIG. FIG. 5 is a schematic cross-sectional view showing the configuration of the metal member joining device 2, and the illustration of a partial configuration is omitted. Further, in FIG. 5, the parts having the same configuration as the metal member joining device 1 according to the first embodiment are designated by the same reference numerals, and detailed description thereof will be omitted below.

As shown in FIG. 5, in the metal member joining device 2, the deformation suppressing unit 20 is provided in the cylinder of the second metal member 104 having a cylindrical shape. The deformation suppressing unit 20 can apply a pressing force outward in the radial direction to the inner peripheral portion 104b of the second metal member 104.

The point that the lower end of the second metal member 104 in the Z direction, that is, the outer peripheral surface of the first metal member 103 on the press-fitting end side into the hole 103a is the tapered portion 104a is the first aspect of the first embodiment. It is the same as the metal member 100.

On the other hand, in the metal member joining device 2 according to the present embodiment, the deformation suppressing unit for applying a tightening load to the outer peripheral portion of the first metal member 103 is not provided. However, although not shown, a positioning device for suppressing the positional deviation of the first metal member 103 on the base 10 is provided.

The press-fit side rim of the hole 103a of the first metal member 103 is a tapered portion 103b. The taper angle of the taper portion 103b is substantially the same as the taper angle of the taper portion 104a of the second metal member 104. Further, the hole diameter of the hole 103a of the first metal member 103 is slightly smaller than the outer diameter of the second metal member 104.

2. Each constituent metal material of the first metal member 103 and the second metal member 104 The constituent metal material of the first metal member 103 is a metal material containing iron (Fe), specifically, carbon steel. Also in this embodiment, as in the first embodiment, S35C is adopted as an example. The yield point (proof stress) of S35C is 305 (N / mm ² ) or more, and the melting temperature is 1538 (° C.). The coefficient of linear expansion is 11.7 (× 10 ⁻⁶ / ° C.).

On the other hand, the constituent metal material of the second metal member 104 is a metal material containing aluminum (Al), specifically, an aluminum alloy. Also in this embodiment, as in the first embodiment, A5056 (H34), which is an Al—Mg-based aluminum alloy, is adopted as an example. The yield point (proof stress) of A5056 (H34) is 230 (N / mm ² ), and the melting temperature is 568 to 638 (° C.). The coefficient of linear expansion is 26.3 (× 10 ^-6 / ° C.).

3. 3. Configuration of Deformation Suppression Unit 20 The configuration of the deformation suppression unit 20 included in the metal member joining device 2 according to the present embodiment will be supplementarily described with reference to FIG. FIG. 6 is a schematic plan view of the deformation suppressing unit 20 as a virtual plan view from above in the Z direction of FIG.

As shown in FIG. 6, the deformation suppressing unit 20 has six deformation suppressing heads 21 to 26. Although not shown, the deformation suppressing unit 20 has a pressing mechanism for moving the deformation suppressing heads 21 to 26 forward and backward in the radial direction.

Each of the deformation suppressing heads 21 to 26 has a fan shape obtained by dividing a circular shape into six parts. The outer peripheral surfaces of the deformation suppressing heads 21 to 26 come into contact with the inner peripheral portion 104b of the second metal member 104 without any gap when the diameter is expanded.

The deformation suppressing unit 20 included in the metal member joining device 2 according to the present embodiment has a mechanism similar to that of a so-called inner diameter grasping collet chuck.

Even when the metal member joining device 2 according to the present embodiment is driven, the deformation suppressing unit 20 is synchronized with the press-fitting of the second metal member 104 into the hole 103a of the first metal member 103 by lowering the welding head 11. Then, a load in the diameter-expanding direction is applied to the inner peripheral portion 104b of the second metal member 104.

4. Joining state of the first metal member 103 and the second metal member 104 The first metal member 103 and the second metal member 104 joined by using the metal member joining device 2 provided with the deformation suppressing unit 20 are shown in FIG. As described above, the formation of burrs and the external discharge are suppressed, and the generation of "unjoined portions" as shown in FIG. 10 is also suppressed. As a result, in the joining using the metal member joining device 2 according to the present embodiment, it is possible to form a long joining portion (diffusion layer 105) having a joining length of _{LB 105} while suppressing an increase in the amount of upset.

Therefore, even in the joining using the metal member joining device 2 according to the present embodiment, the first metal member 103 and the second metal member 104 are joined with high joining strength while suppressing an increase in the upset amount. Can be done.

As shown in FIG. 7, in the metal member joining device 2 according to the present embodiment, the height of the deformation suppressing heads 21 to 26 in the deformation suppressing unit 20 (in FIG. 7, only the deformation suppressing head 23 is shown) in the Z direction. H ₂₃ is set to include the range of plastic flow at the time of joining (the range substantially the same as the range in which the diffusion layer 105 is formed). In other words, the lower surface 23b of the deformation suppressing heads 21 to 26 is substantially flush with the lower end surface of the second metal member 104 in the Z direction, and the upper surface 23a is above the planned region where the diffusion layer 105 is formed. ..

By setting the size and arrangement of the deformation suppressing heads 21 to 26 as described above, in the Z direction, a range including a range of plastic flow at the time of joining (a range substantially the same as the range in which the diffusion layer 105 is formed) is included. , A load outward in the radial direction can be applied to the second metal member 104. As a result, deformation of the second metal member 104 in the radial direction within the range where plastic flow occurs during joining is reliably suppressed, and burr formation and discharge to the outside are suppressed.

5. Effect In the metal member joining device 2, the deformation suppressing unit 20 that suppresses the deformation of the inner peripheral portion 104b of the second metal member 104, which has a lower yield strength and melting temperature of the constituent material than the first metal member 103, in the diameter reduction direction. It is provided. Therefore, it is possible to suppress the diameter-reduced deformation of the second metal member 104 after the second metal member 104 is press-fitted into the hole 103a of the first metal member 103 and the current starts to flow.

Further, since the deformation suppressing unit 20 is provided so as to be able to press the region including the plastic flow range, it is possible to effectively suppress the formation of burrs and the external discharge of burrs at the time of joining.

Therefore, even in the metal member joining device 2 according to the present embodiment, in the joining of the first metal member 103 made of carbon steel and the second metal member 104 made of an aluminum alloy, the upset amount is increased while ensuring high joining strength. The increase can be suppressed.

Further, also in the metal member joining device 2 according to the present embodiment, the deformation suppressing unit 20 applies a load outward in the radial direction, and the welding head 11 lowers to press-fit the second metal member 104 into the hole 103a. Since it can be executed synchronously, it is possible to apply a load for suppressing deformation at an appropriate timing. Therefore, it is possible to efficiently suppress an increase in the amount of upset while ensuring high bonding strength.

Further, the deformation suppressing unit 20 in the metal member joining device 2 has six deformation suppressing heads 21 to 26. As a result, pressing with less bias is possible, and deformation of the second metal member 104 in the diameter reduction direction in the cross-sectional direction can be suppressed without bias.

[Third Embodiment]
The configuration of the metal member joining device according to the third embodiment of the present invention will be described with reference to FIG. Note that FIG. 8 shows a partial configuration of the deformation suppressing unit 30 extracted from the configuration of the metal member joining device according to the present embodiment. Each configuration (not shown) is the same as the metal member joining device 1 according to the first embodiment.

As shown in FIG. 8, the deformation suppressing unit 30 included in the metal member joining device according to the present embodiment includes three deformation suppressing heads 31 to 33 and pressing rods 34 to 34 connected to the deformation suppressing heads 31 to 33. 36 and. Although not shown, the deformation suppressing unit 30 is connected to the pressing rods 34 to 36 and has a pressing mechanism for moving the deformation suppressing heads 31 to 33 forward and backward in the radial direction.

Each of the deformation suppressing heads 31 to 33 has a planar shape in which an annulus is divided into three. The deformation suppressing heads 31 to 33 are arranged so that their ends face each other.

With respect to the second metal member 101 having the hole 101a, the inner peripheral surfaces of the deformation suppressing heads 31 to 33 are aligned with the outer peripheral portion 101c without any gap. As shown by the arrow _A 4 to A _6, in advance the deformation suppressing head 31-33 radially inward, it is brought into contact respectively with respect to the outer peripheral portion 101c of the second metal member 101 state, deformation restricting head between each of the 31 to 33, the gap _{G 3,} G 4, _{G 5} is adapted to lye respectively. Gap _{G 3,} G 4, _{G 5} are minute gaps.

Also in this embodiment, are you to open a gap _{G 3,} G 4, _{G 5} is the same manner as described above, and dimensional tolerance of the second metal member 101, there is such dimensional tolerance deformation suppressing head 31-33 However, this is so that the deformation of the second metal member 101 can be suppressed.

Even in the metal member joining device having the deformation suppressing unit 30 having the above configuration, it is possible to obtain the same effect as that of the metal member joining device 1 according to the first embodiment.

[Fourth Embodiment]
The configuration of the metal member joining device according to the fourth embodiment of the present invention will be described with reference to FIG. Note that FIG. 9 shows a partial configuration of the deformation suppressing unit 40 extracted from the configuration of the metal member joining device according to the present embodiment.

First, in the first to third embodiments, a member having a circular shape or an annular cross-sectional shape is adopted as the member to be joined, but in the present embodiment, as shown in FIG. 9, the cross section is used. The second metal member 106 having a square annular surface shape is one of the objects to be joined.

Although not shown, the other side to be joined is a rod or cylinder metal member having a quadrangular cross-sectional shape corresponding to the shape of the hole 106a in the second metal member 106.

As shown in FIG. 9, the deformation suppressing unit 40 of the metal member joining device according to the present embodiment includes four deformation suppressing heads 41 to 44 and four pressing heads 45 to 48. Each of the four deformation suppressing heads 41 to 44 can come into contact with the four outer peripheral portions 106c to 106f of the second metal member 106 without any gap. Although not shown, the four pressing heads 45 to 48 are connected to a pressing mechanism and are indicated by arrows A _{7 to} A ₁₀ in synchronization with press fitting of the first metal member into the hole 106a. In addition, a tightening load can be applied inward to the second metal member 106.

Even in the metal member joining device having the deformation suppressing unit 40 having the above configuration, it is possible to obtain the same effect as that of the metal member joining device 1 according to the first embodiment.

[Modification example]
In the first to fourth embodiments, a member containing Al (Al alloy) and a member containing Fe (carbon steel) are used as the members to be joined, but the present invention is limited thereto. I don't receive it. In the present invention, it is possible to exert an effect by providing the deformation suppressing unit as described above for joining members made of materials having at least one of different proof stress and melting temperature.

For example, joining a member made of a material containing magnesium (Mg) (for example, Mg alloy) and a member made of a material containing Al (for example, Al alloy), or a member made of a material containing Mg (for example, Mg alloy). It can also be applied to joining a member made of a material containing Fe and (for example, carbon steel). Even in these cases, the deformation suppressing unit can be provided in consideration of at least one of the proof stress and the melting temperature of the material constituting the member.

When MDC1D is used as the Mg alloy, for example, the yield point (proof stress) is 160 (N / mm ² ) and the melting temperature is 470 to 595 (° C.). The coefficient of linear expansion is 27.0 (× 10 ⁻⁶ / ° C.). The relationship between these physical properties and the materials constituting the members to be joined may be taken into consideration.

In the second embodiment, the deformation suppressing unit 20 is provided on the second metal member 104 to prevent the second metal member 104 from shrinking in diameter at the time of joining with the first metal member 103. In the present invention, for example, in the second embodiment, the deformation suppressing unit may be further provided on the first metal member 103. This means that when a welding current is applied, the temperatures of the members 103 and 104 rise, and each member tends to expand. In this case, the first metal member 103 made of carbon steel and having an annular shape tries to increase the diameter. By suppressing this, it is effective in suppressing the formation of burrs and the discharge to the outside. Deformation suppression unit for metal members to be joined so that the same effect can be obtained by considering the coefficient of linear expansion together with the proof stress and melting temperature of the constituent materials of each member even when the constituent materials are other than the above. Can be configured.

In the first to fourth embodiments, examples are shown with respect to the shapes of the members 100, 101, 103, 104, 106 to be joined, but the present invention is not limited thereto. For example, a member having an oval ring shape in a plan view, a member having a polygonal outer peripheral shape of a triangle or a pentagon or more can be joined. In this case, the same effect as described above can be obtained by providing the deformation suppressing head corresponding to the shape of the outer peripheral portion.

In the first to fourth embodiments, the deformation suppressing units 17, 20, 30, and 40 are provided to suppress the deformation of the second metal members 101, 104, and 106. The deformation suppressing units 17, 20, 30, and 40 in these embodiments have a function of suppressing deformation of the second metal members 101, 104, and 106 in the cross-sectional direction.

However, the present invention is not limited thereto. For example, a welding current may be applied to partially soften the metal member on the lower melting temperature side, and the softened metal member may be deformed in the cross-sectional direction toward the other metal member to be joined. .. With such a configuration, it is advantageous to suppress a decrease in density in the plastically flowed region in the cross-sectional direction and to secure high bonding strength.

In the first embodiment, the third embodiment, and the fourth embodiment, a tightening load is applied to the outer peripheral portions 101c, 106c, 106d, 106e, 106f of the second metal members 101, 106. The invention is not limited to this. For example, the upper surface in the Z direction of the outer edge portion of the second metal member 101 of FIG. 1 may be pressed toward the base 10 side to suppress the radial deformation of the second metal member 101 due to frictional force. Good.

In the first embodiment, the second metal member 101 is mounted on the upper surface 10a of the base 10, and in the second embodiment, the first metal member 103 is mounted. However, the present invention relates to this. It is not limited. For example, a second welding head facing the welding head 11 is provided, and the second metal member 101 and the first metal member 103 are gripped by the second welding head, so that the welding head rises upward in the Z direction during welding. May be.

From the first embodiment to the third embodiment, the deformation suppressing heads 13, 14, 21 to 26, 31 to 33 are configured to be able to move forward and backward only in the radial direction, but the present invention is limited to this. I don't receive it. For example, each deformation suppressing head may be spirally rotated to increase or decrease the diameter.

Further, the first embodiment includes two deformation suppressing heads 13 and 14, the second embodiment includes six deformation suppressing heads 21 to 26, and the third embodiment includes three deformations. The suppression heads 31 to 33 are provided, and in the fourth embodiment, the four deformation suppression heads 41 to 44 are provided, but the present invention is not limited thereto. For example, in FIG. 1, an annular deformation suppressing head integrally formed may be prepared and brought into close contact with the outer peripheral portion of the annular second metal member 101.

Further, as described above, the size of the deformation suppressing head in the press-fitting direction of the metal member is limited to each of the above embodiments as long as the size includes the range of the plastic flow of the metal member to be joined. is not.

Further, in the first embodiment and the second embodiment, the tapered portions 100a, 101b, 103b, 104a are provided on the metal members 100, 101, 103, 104 to be joined, but in the present invention, the tapered portions 100a, 101b, 103b, 104a are provided. It is not always necessary to provide the tapered portion.

1,2 Metal member joining device 11 Welding head 13,14,21,22,23,24,25,26,31,32,33,41,42,43,44 Deformation suppression head 17,20,30,40 Deformation Suppression unit 18 Welding current supply unit 100, 103 First metal member 101, 104, 106 Second metal member 102, 105 Diffusion layer

Claims (4)

In a metal member joining device for joining a rod-shaped or tubular first metal member by press-fitting it into a hole of an annular second metal member.
The first metal member is made of a first metal material.
The second metal member is made of a second metal material different from the first metal material, and the size of the hole in the cross section is smaller than the size of the first metal member in the cross section.
The metal member joining device is
The table on which the second metal member is placed and
A pressurizing means for pressurizing and press-fitting the first metal member toward the hole of the second metal member while the second metal member is placed on the table.
A current supply means for supplying a welding current between the first metal member and the second metal member,
Among the first metal member and the second metal member, the member on the side where at least one of the proof stress and the melting temperature of the constituent metal material is lower is in the cross-sectional direction which is the direction intersecting the press-fitting direction. Deformation suppressing means for suppressing deformation of
With
The deformation suppressing means is provided in a region including at least a plastic flow range in the press-fitting direction.
The proof stress and melting temperature of the second metal material are lower than those of the first metal material.
The deformation suppressing means applies a tightening load to the second metal member inward in the cross-sectional direction from the outer peripheral portion of the second metal member.
The deformation suppressing means is
A plurality of deformation suppressing heads arranged along the outer peripheral portion of the second metal member, and
It has a pressing mechanism that presses each of the plurality of deformation suppressing heads inward in the cross-sectional direction.
The plurality of deformation suppressing heads are adjacent to each other in the outer peripheral direction of the second metal member, and are tightened so that they are in close contact with the outer peripheral portion without a gap by receiving a pressing force from the pressing mechanism. Add a load ,
The addition of the tightening load by the deformation suppressing means is performed in synchronization with the press-fitting of the first metal member into the hole of the second metal member by the pressurizing means.
Joining device for metal parts. The metal member joining device according to claim 1 .
The second metal material is a material containing aluminum.
The first metal material is a material containing iron.
Joining device for metal parts. In a method for joining a metal member in which a rod-shaped or tubular first metal member is press-fitted into a hole of an annular second metal member to be joined.
A first metal member preparation step for preparing the first metal member made of the first metal material, and
A second metal member for preparing the second metal member, which is made of a second metal material different from the first metal material and whose cross-sectional size of the hole is set to be smaller than the cross-sectional size of the first metal member. Preparation steps and
A mounting step for mounting the second metal member on a table, and
A pressurizing step of pressurizing the first metal member toward the hole of the second metal member and press-fitting the first metal member while the second metal member is placed on the table.
A current supply step for supplying a welding current between the first metal member and the second metal member,
A deformation suppressing step of suppressing deformation in the cross-sectional direction with respect to a member of the first metal member and the second metal member on which at least one of the proof stress and the melting temperature of the constituent metal material is lower.
With
In the deformation suppressing step, deformation is suppressed at least in a region including a plastic flow range in the press-fitting direction.
The proof stress and melting temperature of the second metal material are lower than those of the first metal material.
In the deformation suppressing step,
A plurality of deformation suppressing heads arranged along the outer peripheral portion of the second metal member, and
An inward tightening load in the cross-sectional direction is applied by using a pressing mechanism that presses each of the plurality of deformation suppressing heads inward in the cross-sectional direction.
The plurality of deformation suppressing heads are adjacent to each other in the outer peripheral direction of the second metal member, and receive the pressing force from the pressing mechanism to apply the tightening load so that each of them comes into contact with the outer peripheral portion without a gap. Add ,
The addition of the tightening load in the deformation suppressing step is performed in synchronization with the press-fitting of the first metal member into the hole of the second metal material in the pressurizing step.
How to join metal members. The method for joining metal members according to claim 3 .
The second metal material is a material containing aluminum.
The first metal material is a material containing iron.
How to join metal members.