Joining apparatus and joining method for friction stir welding and resistance welding

Abstract

A joining device and joining method for friction stir bonding and resistance welding. The joining device for joining a first component (3), an intermediate component (4) and a second component (5) stacked as a laminate assembly includes: a probe (12, 41, 52); an anvil (111, 121); an electrical conductor configured to contact a second surface of the laminate assembly, the electrical conductor being the probe or a shoulder component (13, 13a, 61, 64, 68) having a through hole for receiving the probe and a shoulder contact surface configured to abut against the second surface; a drive mechanism (14) configured to rotate the probe about a central axis and move the probe toward and away from the second component along the central axis; and a power source (15) electrically connected to the anvil and the probe to conduct power through the laminate assembly via the anvil and the probe.

Description

Technical Field

[0001] This invention relates to a joining device and a joining method for friction stir joining and resistance welding. Background Technology

[0002] Resistance welding and friction stir joining are known to be environmentally friendly processes for joining multiple sheet metal components because they emit relatively small amounts of gas and have a very small impact on air quality. Friction stir joining is particularly preferred because this process requires relatively little electricity.

[0003] When resistance welding three or more sheet metal components made of different materials, a bonding agent is typically used to prevent electrolytic corrosion. However, it is difficult to prevent inherent defects in the bonding agent, and stable bond strength cannot be maintained for a long time without highly stringent preventative measures. When a high level of reliability is required, rivets must be used in conjunction. Friction stir bonding is suitable for joining two sheet metal components made of different materials, but it may not be suitable for joining three or more sheet metal components due to the limited range of materials that can be effectively stirred. For example, when an aluminum sheet component and a pair of steel sheet components are joined by friction stir bonding, the upper two components (e.g., the aluminum sheet component and the steel sheet component) may be properly joined, but the third or bottommost component may be improperly joined to the other two components.

[0004] JP2005-111489A discloses a method for joining three or more metal components, including metal components made of different materials, by combining two joining techniques. According to this prior art, an aluminum component, a steel component, and a cladding component comprising aluminum and steel layers are joined together by friction stir bonding, whereby the aluminum component is bonded to the aluminum layer of the cladding component, and the steel component and the steel layer of the cladding component are simultaneously bonded using a thermosetting adhesive, which is cured by the frictional heat of the friction stir bonding. However, this method requires the presence of a cladding component in one of the components to be joined.

[0005] In the process disclosed in JP2007-237253A, a pair of components abut against each other and are joined together by friction stirring, and a third component is joined to the joint by means of fusion welding or resistance welding.

[0006] When three or more metal components made of different materials are involved, two or more different joining methods are required. According to existing technology, the entire joining process must be carried out in multiple steps and requires two or more different joining devices, resulting in extended production lines and significant investment.

[0007] In view of these problems in the prior art, the main objective of this invention is to provide a joining device and method for joining three or more components, which allows for a reduction in the time required for the joining process and a reduction in the cost of production equipment. This invention can help minimize the environmental impact on air and improve the energy efficiency of production equipment. Summary of the Invention

[0008] To achieve this objective, one aspect of the invention provides a joining device 1, 51 for joining a first component 3, an intermediate component 4, and a second component 5 together, the first component, the intermediate component, and the second component being conductive, extending along a predetermined principal plane, and stacked in this order to form a laminated assembly 2. The joining device includes: anvils 111, 121, each anvil having anvil contact surfaces 112, 122 for supporting a first surface of the laminated assembly provided by the first component, the anvil contact surfaces including electrically insulating regions 113, 123 and conductive regions 114, 124; and probes 12, 41, 52, each probe being positioned corresponding to a first surface of the laminated assembly provided by the second component. The components provide a second surface 7 opposite to each other and are configured to rotate about a central axis intersecting the main plane and move toward and away from the second component; drive mechanisms 14, 54, configured to rotate the probe about the central axis and move the probe toward and away from the second component along the central axis; power supply 15, electrically connected to the anvil and the probe to conduct current through the laminated assembly via the anvil and the probe; and control unit 16, for controlling the operation of the drive mechanisms and the power supply such that the first component and the intermediate component are joined together by resistance welding, and the second component and the intermediate component are joined together by friction stirring.

[0009] According to this aspect of the invention, since the anvil and probe used for friction stir welding also serve as electrodes for resistance welding, equipment costs can be reduced, equipment size can be decreased, and the length of the production line can be shortened. Furthermore, since friction stir welding and resistance welding can be performed simultaneously, processing time can be reduced.

[0010] To achieve this objective, another aspect of the invention provides a joining device 1, 51 for joining a first component 3, an intermediate component 4, and a second component 5 together, wherein the first component, the intermediate component, and the second component are conductive, extend along a predetermined main plane, and are stacked in this order to form a laminate assembly 2. The joining device includes: anvils 111, 121, each anvil having anvil contact surfaces 112, 122 for supporting a first surface of the laminate assembly provided by the first component, the anvil contact surfaces including electrically insulating regions 113, 123 and conductive regions 114, 124; and probes 12, 41, each probe being positioned opposite a second surface 7 of the laminate assembly provided by the second component at a corresponding probe location, and configured to rotate about a central axis intersecting the main plane and toward and away from the second surface 7. Component movement; shoulder components 13, 13a, 61, 64, 68, the shoulder components having through holes 20, 20a for receiving the probe and shoulder contact surfaces 24, 24a configured to abut against the second surface, the shoulder components being at least partially conductive; a drive mechanism 14, the drive mechanism being configured to rotate the probe about the central axis and to move the probe toward and away from the second component along the central axis; a power supply 15, the power supply being electrically connected to the anvil and the shoulder components to conduct current through the laminated assembly via the anvil and the shoulder components; and a control unit 16, the control unit being configured to control the operation of the drive mechanism and the power supply such that the first component and the intermediate component are joined together by resistance welding, and the second component and the intermediate component are joined together by friction stirring.

[0011] According to this aspect of the invention, since the anvil and shoulder members used for friction stir joining also serve as electrodes for resistance welding, equipment costs can be reduced, equipment size can be decreased, and the length of the production line can be shortened. Furthermore, since friction stir joining and resistance welding can be performed simultaneously, processing time can be reduced.

[0012] Preferably, the shoulder member is provided with recesses 25, 25a that are recessed relative to the shoulder contact surface to define a bottom surface 26, 26a opposite to the second surface and to partially receive the probe.

[0013] Due to the presence of the recess, the shoulder contact surface can be formed into an annular shape or distributed in the radially outer region, so that the weld nugget is distributed in the radially outer region. As a result, the bonding strength provided by the weld nugget can be improved.

[0014] Preferably, the electrically insulating region 113 is centrally located on the contact surface 112 of the anvil.

[0015] Therefore, the fusion nugget forms in the radially outer region, thereby increasing the bonding strength and advantageously dispersing the stress during bonding.

[0016] Preferably, the conductive region 114 is arranged in an annular shape around the electrically insulating region 113 on the anvil contact surface 112.

[0017] Therefore, the fusion nugget is formed in a ring shape in the radially outer region, thereby increasing the bonding strength and advantageously dispersing the stress during bonding.

[0018] Preferably, the conductive region 124 is disposed as multiple segments on the anvil contact surface 112, and the multiple segments are isolated and separated from each other by a portion of the electrically insulating region 123.

[0019] Because the conductive region is divided into multiple isolated segments, the molten nucleus forms as a set of mutually separated segments, which is particularly advantageous for dispersing stress during bonding.

[0020] Therefore, the present invention provides a joining device and a joining method for joining three or more components, which allows for a reduction in the time required for the joining process and a reduction in the expenditure on production equipment. Attached Figure Description

[0021] Figure 1 This is a vertical cross-sectional view showing the joining device according to a first embodiment of the present invention;

[0022] Figures 2A to 2C Different examples of electrical insulation in a joining device are shown;

[0023] Figure 3A It shows Figure 1 The cross-sectional and plan views of the shoulder component of the connecting device are shown.

[0024] Figure 3B It shows something similar to Figure 3A The improved shoulder component is shown.

[0025] Figures 4A to 4E This is a diagram illustrating different stages of the joining method according to a first embodiment of the present invention;

[0026] Figure 5 It is similar to Figure 1 The view shows the joining device according to a second embodiment of the present invention;

[0027] Figure 6 It is similar to Figure 1 The view shows the joining device according to a third embodiment of the present invention;

[0028] Figure 7This is a partial vertical cross-sectional view showing a modified example of the probe of the coupling device according to a third embodiment of the present invention;

[0029] Figures 8A to 8D This is a partial cross-sectional view showing different examples of a shoulder member according to a third embodiment of the present invention;

[0030] Figures 9A to 9D This is a cross-sectional view of a joining device according to a third embodiment of the present invention, showing different examples of the joining device having an anvil:

[0031] Figures 10A to 10E This is a diagram illustrating different stages of a joining method using the joining device according to a third embodiment of the present invention;

[0032] Figures 11A to 11C This is a diagram illustrating different stages of an improved joining method using the joining device of the third embodiment;

[0033] Figure 12 It is an improved anvil that can be used in any joining device from the first to the third embodiments;

[0034] Figure 13A This is a vertical cross-sectional view showing a variation of the anvil in the first and second embodiments;

[0035] Figure 13B This is a vertical cross-sectional view showing a variation of the anvil in embodiment 3-2;

[0036] Figure 14A These are variations of the anvil in the first to third embodiments of the present invention; and

[0037] Figure 14B Is using Figure 14A The diagram shows a horizontal cross-section of the nugget produced by the anvil. Detailed Implementation

[0038] Preferred embodiments of the present invention will now be described with reference to the accompanying drawings. Figure 1 This is a vertical cross-sectional view of the bonding device 1 and the laminated assembly 2 processed by the bonding device 1 according to a first embodiment of the present invention. In the following description, the laminated assembly 2 extends along a horizontal plane (main plane), and the bonding device 1 is applied downward in the vertical direction to the laminated assembly 2. However, this orientation is merely exemplary, and the invention can be applied to workpieces oriented in any desired direction and from any desired direction, such as laterally, upward, and obliquely, without departing from the scope of the invention.

[0039] The laminate assembly 2 includes a first member 3, an intermediate member 4, and a second member 5, all of which are composed of conductive plate members and are stacked in this order on a horizontal main plane. The laminate assembly 2 has a first surface 6 provided by the lower surface (bottom layer) of the first member 3 and a second surface 7 provided by the upper surface (top layer) of the second member 5. In another embodiment, the laminate assembly 2 further includes an additional member below the first member 3, which is made of the same or similar material as the first member 3.

[0040] In this embodiment, the first component 3 and the intermediate component 4 are made of the same or similar materials, while the second component 5 is made of a different or dissimilar material than the first component 3 and the intermediate component 4. The materials of the first component 3 and the intermediate component 4 have higher strength and higher electrical resistance than the material of the second component 5. For example, the first component 3 and the intermediate component 4 may be made of an iron alloy (steel), while the second component 5 may be made of an aluminum alloy, a magnesium alloy, or a copper alloy. Alternatively, the first component 3 and the intermediate component 4 may be made of a titanium alloy, while the second component 5 may be made of an aluminum alloy, a magnesium alloy, or a copper alloy. Furthermore, the first component 3 and the intermediate component 4 may be made of an aluminum alloy, while the second component 5 may be made of a copper alloy.

[0041] The bonding device 1 includes: an anvil 11 configured to support a first surface 6 of the laminating assembly 2; a probe 12 positioned above the anvil 11; an annular shoulder member 13 positioned above the anvil 11 and surrounding the probe 12; a drive mechanism 14 for driving the anvil 11, the probe 12, and the shoulder member 13, as described below; a power supply 15 for conducting current between the probe 12 and the anvil 11, through which the laminating assembly 2 is inserted; and a control unit 16 for controlling the operation of the drive mechanism 14 and the power supply 15.

[0042] The anvil 11 is made of conductive material and has an anvil contact surface 17 that abuts against the first surface 6 of the laminate 2.

[0043] The probe 12 is disposed in the free end (lower end) portion of the rotatable member 18, which is rotatable about a central axis and has a shape that is rotationally symmetrical about the central axis. The probe 12 extends along the central axis and preferably has a cylindrical shape, the diameter of which is smaller than the diameter of the base portion 19 of the rotatable member 18. The probe 12 is made of a hard material such as steel, ceramic, or hard alloy.

[0044] like Figure 1As shown, the shoulder member 13 has a rotationally symmetrical shape about a central axis. The shoulder member 13 includes: a probe support 21 having a through hole 20 centered on the central axis; a flange 22 extending radially outward from the probe support 21; and an annular sidewall 23 protruding downward from the lower surface of the probe support 21, concentric with the central axis. The probe 12 passes through the through hole 20. The upper end of the through hole 20 is formed as a tapered countersunk hole. The inner diameter of the lower part (main part) of the through hole 20 is slightly larger than the outer diameter of the probe 12, and the inner circumferential surface of the through hole 20 can slide in contact with the outer circumferential surface of the probe 12 when the probe 12 rotates about the central axis. The inner diameter of the sidewall 23 is substantially larger than the outer diameter of the probe 12, such that the inner circumferential surface of the sidewall 23 is concentrically separated from the outer circumferential surface of the probe 12. The inner circumferential surface of the sidewall 23 can be tapered towards its lower end, but can also be approximately parallel to the axial direction. The lower surface of the sidewall portion 23 forms a shoulder contact surface 24, which can abut against the second surface 7 of the laminate assembly 2. Therefore, the recess 25 is defined by the lower surface of the probe support portion 21 opposite to the second surface 7 of the laminate assembly 2 and the inner peripheral surface of the sidewall portion 23, and the recess 25 is recessed relative to the shoulder contact surface 24. The shoulder member 13 can be made of a hard material such as copper alloy (chromium copper, copper with dispersed alumina, tungsten copper alloy, etc.), conductive ceramic, hard alloy, etc.

[0045] like Figure 1 As shown, the drive mechanism 14 includes an anvil drive mechanism 27 for vertically moving the anvil 11, a rotation drive mechanism 28 for rotating the rotatable member 18 including the probe 12 about the central axis, a forward / backward drive mechanism 29 for moving the probe 12 forward / backward along the central axis, and a shoulder drive mechanism 30 for vertically moving the shoulder member 13.

[0046] Power supply 15 is electrically connected to a first terminal 31 and a second terminal 32. The first terminal 31 is electrically connected to an anvil 11, and the second terminal 32 is electrically connected to a rotatable member 18 (each via a sliding contact mechanism or a flexible cable). The anvil 11 is at least partially conductive, so that current can be supplied to the anvil contact surface 17 via the first terminal 31, and the rotatable member 18 is at least partially conductive, so that current can be supplied to the tip of the probe 12 via the second terminal 32.

[0047] The following will refer to Figures 4A to 4E describe Figure 1 The operating mode of the bonding device 1 shown in the diagram when processing the laminating assembly 2.

[0048] like Figure 4AAs shown, the first component 3, the intermediate component 4, and the second component 5 are placed on the anvil 11, and the probe 12 and the shoulder component 13 are positioned above the second surface 7. The probe 12 and the shoulder component 13 move downward so that, under the control of the control unit 16, the laminating assembly 2 is brought against the anvil 11 by using the drive mechanism 14, in preparation for friction stir point bonding and resistance spot welding, as described below.

[0049] like Figure 4B As shown, the anvil 11 presses the first surface 6 of the laminating assembly 2 from below, and the shoulder member 13 presses the second surface 7 of the laminating assembly 2 from above. When the laminating assembly 2 is pressed between the anvil 11 and the shoulder member 13, the probe 12 rotates about the central axis and advances into the laminating assembly 2 from the side of the second surface 7.

[0050] like Figure 4C As shown, the tip of probe 12 is inserted into the second member 5, causing the second member 5 to deform, displacing material from it into the recess 25 of the shoulder member 13. Due to the frictional heat generated by rotating probe 12, the material surrounding the second member 5 becomes a plastic fluid, creating an annular plastic fluid region around probe 12. Once the tip of probe 12 reaches the intermediate member 4, control unit 16 causes current to flow between probe 12 and anvil 11. The position of the tip of probe 12 can be detected or managed by the downward stroke of probe 12, the insertion pressure (insertion load) of probe 12 into the lamination assembly 2, the rotational load of probe 12, or any combination thereof.

[0051] like Figure 4D As shown, when current flows between probe 12 and anvil 11, probe 12 continues to rotate and move further downward, and the tip of probe 12 is inserted into intermediate member 4. As a result, the resistance heat generated in the first member 3 and intermediate member 4 and the frictional heat generated by the rotation of probe 12 cause a melting zone 34 to be formed in or between the first member 3 and intermediate member 4. At the same time, a portion of the material of the second member 5 and intermediate member 4 near probe 12 plastically flows. In particular, the portion of the material that is further pushed away from probe 12 is cooled and becomes relatively less fluid, but is pushed away from probe 12 under pressure from the larger fluid portion of the material. As a result, a hook 35 is formed in the portion of intermediate member 4 surrounding probe 12 that projects radially outward and upward. The hook 35 thus has a crown-like shape that opens toward its front end (upper end) and extends obliquely into or weds into the material of second member 5.

[0052] like Figure 4E As shown, control unit 16 (see...) Figure 1The current supply between probe 12 and anvil 11 is stopped, and probe 12 is moved backward along the axis while rotating. Additionally, anvil 11 and shoulder member 13 move away from laminating assembly 2. When the current stops and probe 12 is removed, the melting zone 34 (see...) Figure 4D The solidification forms a molten core 33, which firmly bonds the first member 3 and the intermediate member 4 together. Furthermore, since the hook 35 is formed in the second member 5 and the intermediate member 4, which have been plastically flowed by the rotation of the probe 12, the second member 5 and the intermediate member 4 are also firmly bonded together.

[0053] Figure 2C The diagram illustrates the current distribution supplied by power source 15 to probe 12, which flows through lamination assembly 2 to anvil 11 as the tip of probe 12 is pushed into lamination assembly 2 from second surface 7. Shaded (gray) arrows indicate downward movement of probe 12, thin arrows indicate rotation of probe 12, and thick arrows indicate current flow. Due to this current, a weld nugget 33 forms between first member 3 and intermediate member 4, binding them together. However, a portion of the current is conducted through shoulder member 13 instead of being concentrated in intermediate member 4 and first member 3, reducing the energy efficiency of resistance welding. Therefore, it is desirable to use... Figure 2A and Figure 2B The arrangement shown is to eliminate or reduce current flow through the shoulder member 13. In the following description of these examples, with... Figure 2C The corresponding components are indicated by the same reference numerals in the accompanying drawings, and it is not necessary to repeat the description of these components to avoid redundancy.

[0054] exist Figure 2A In the example shown, probe 41 includes: a probe conductive portion 42 having a cylindrical shape and extending coaxially along a central axis; and a probe insulating portion 43 disposed on the outer peripheral surface of the probe conductive portion 42. The lower end surface of the probe conductive portion 42 is not covered by the probe insulating portion 43 and is exposed. Therefore, when probe 41 is received in the through-hole 20 of shoulder member 13, only the probe insulating portion 43 slides in contact with the inner peripheral surface of the through-hole 20 of shoulder member 13. The probe insulating portion 43 prevents current from flowing from probe 41 to shoulder member 13. To improve the wear resistance of probe 41, an additional layer (not shown) (which may be conductive or electrically insulating) may be formed on the outer peripheral surface of probe insulating portion 43. Alternatively or additionally, an insulating layer may be formed on the inner peripheral surface of the through-hole 20 of shoulder member 13.

[0055] exist Figure 2B In the example shown, the shoulder member 13 is provided with... Figure 1The shoulder member 13 shown is essentially the same as the main body 45, and is provided with a shoulder member insulating layer 46 extending on the inner circumferential surface of the through hole 20, the lower and inner circumferential surfaces of the annular sidewall portion 23, and the bottom surface 26 of the recess 25. The shoulder member insulating layer 46 prevents current from flowing from the probe 41 to the shoulder member 13.

[0056] exist Figure 2A and Figure 2B In the example shown, the conductive portion 42 and the main body 45 of the probe can be made of copper alloy (e.g., chromium copper, copper with dispersed alumina, tungsten copper alloy, etc.), conductive ceramic material, hard alloy, etc. The insulating portion 43 of the probe and the insulating layer 46 of the shoulder component can be made of insulating ceramic material, Bakelite (a registered trademark) (phenolic resin), mica, etc.

[0057] The friction stirring joint performed by the aforementioned jointing device 1 is a friction stirring point joint, and the shoulder contact surface 24 of the shoulder member 13 contributes to a good appearance of the joint point. Figure 3A Showing more details Figure 1 The shoulder member 13 of the connecting device 1 shown.

[0058] Figure 3B An alternative embodiment of the shoulder member 13a is shown. Figure 3B In, with Figure 3A Corresponding components are indicated by the same reference numerals, each number followed by the letter "a". In this case, the sidewall portion 23a is U-shaped, such that the recess 25a has an opening on one side, which is defined by a pair of mutually parallel straight sections of the sidewall portion 23a on the rear side of the shoulder member 13a relative to the direction of travel of the shoulder member 13a relative to the laminating assembly 2 during in-line joining. According to this embodiment, by using an assembly with Figure 3B The joining device 1 of the shoulder member 13a shown causes the laminating assembly 2 to move relative to the joining device 1 along a horizontal line, allowing the laminating assembly 2 to be advantageously joined along the line. Although Figure 4A The shoulder member 13 shown can be used for frictional stirring engagement along a line, but Figure 4B The embodiment shown is advantageous because the open side of the recess 25a allows the laminating assembly 2 to move relative to the bonding device 1 with relatively little resistance. The sidewall portion 23a may also include a pair of parallel portions extending along the relative movement between the laminating assembly 2 and the bonding device 1.

[0059] The various features and advantages of the above-described embodiments will be discussed below.

[0060] In the aforementioned joining device 1, the anvil 11 and probe 12 used for friction stir bonding can also be used as electrodes for resistance spot welding. Compared to using a friction stir bonding device and a resistance spot welding device separately, the cost and size of the joining device 1 can be minimized. In particular, by using the aforementioned joining device 1, the length of the production line can be reduced, and the necessary investment can be decreased. Furthermore, since friction stir bonding and resistance spot welding can be performed simultaneously, the time required for the manufacturing process can be reduced.

[0061] When resistance welding dissimilar materials, very brittle intermetallic compounds are often formed, resulting in a failure to achieve the desired bond strength. In the above embodiment, since the second component 5 and the intermediate component 4, which may be made of different materials, are joined by friction stir bonding instead of resistance welding, this reduction in bond strength due to intermetallic compounds is prevented.

[0062] In the above embodiment, the frictional heat generated by the probe 12 during the friction-stirring bonding of the intermediate component 4 and the first component 3 facilitates the resistance welding of the intermediate component 4 and the first component 3, thereby reducing the energy consumption of resistance welding. In resistance welding, it is known that if the molten region 34 cools too quickly, the toughness of the weld nugget 33 may decrease. In the aforementioned embodiment, since the probe 12 remains rotating and is pulled out from the lamination assembly 2 after the current for resistance welding is stopped, the frictional heat generated by the probe 12 is conducted to the molten region 34, thereby preventing the molten region 34 from cooling rapidly and preventing a decrease in the toughness of the weld nugget 33.

[0063] exist Figure 2A and Figure 2B In the example shown, the presence of the probe insulation portion 43 and the shoulder member insulation layer 46 completely or significantly prevents current from flowing through the shoulder member 13, and a very small portion of the current flows through the second member 5, thereby preventing the melting of the second member 5. As a result, the bonding quality can be stabilized and improved, and the electrical safety of the device can be enhanced.

[0064] Figure 5 A coupling device 51 according to a second embodiment of the present invention is shown. Components corresponding to those in the first embodiment are indicated by the same reference numerals, and their description need not be repeated. The coupling device 51 of the second embodiment includes an anvil 11, a rotatable member 53 including a probe 52, a drive mechanism 54, a power supply 15, and a control unit 16 for controlling the operation of the drive mechanism 54 and the power supply 15. The drive mechanism 54 includes a rotation drive mechanism 28, a forward / reverse drive mechanism 29, and an anvil drive mechanism 27.

[0065] The rotatable member 53 is generally rotatable about a central axis. The rotatable member 53 includes a base portion 55 having a generally cylindrical shape centered on the central axis and a probe 52 extending downward from the lower surface of the body 45. The rotatable member 53 is substantially fully conductive. The probe 52 has a generally cylindrical shape coaxial with the base portion 55 and a smaller diameter compared to the base portion 55. The probe 52 preferably has threads or any other irregular surface features on its outer periphery. In this case, there is no shoulder member. A downward-facing annular shoulder surface 56 is defined at the boundary between the base portion 55 of the rotatable member 53 and the probe 52. The shoulder surface 56 may have a convex profile such that the radially inner portion is vertically recessed compared to the radially outer portion. The probe 52 may be made of a hard material such as a copper alloy (chromium copper, copper with dispersed alumina, tungsten copper alloy, etc.), conductive ceramic, hard alloy, etc.

[0066] Except for the absence of shoulder member 13, the operating mode of the coupling device 51 in the second embodiment is similar to that in the first embodiment. The annular shoulder surface 56 provides a recess into which the plastic flow material of the second member 5 is transferred, similar to the recess 25 of the shoulder member 13 in the first embodiment (see...). Figure 1 ).

[0067] Reference Figure 6 The coupling device 101 according to a third embodiment of the present invention is described. Components corresponding to those in the first embodiment are indicated by the same reference numerals, and their descriptions need not be repeated to avoid redundancy. The coupling device 101 of the third embodiment is similar to the coupling device of the first embodiment, but differs from the first embodiment in that the power supply 15 is electrically connected to the anvil 11 and the shoulder member 13, whereas in the first embodiment, the power supply 15 is electrically connected to the anvil 11 and the probe 12.

[0068] Power supply 15 is electrically connected to a first terminal 31 and a second terminal 32. The first terminal 31 is electrically connected to an anvil 11, and the second terminal 32 is electrically connected to a shoulder member 13 (each via a sliding contact mechanism or a flexible cable). The anvil 11 is at least partially conductive, so that current can be supplied to the anvil contact surface 17 via the first terminal 31, and the shoulder member 13 is at least partially conductive, so that current can be supplied to the shoulder contact surface 24 via the second terminal 32.

[0069] The following will refer to Figures 10A to 10E describe Figure 6 The operating mode of the bonding device 101 shown when processing the laminating assembly 2.

[0070] like Figure 10AAs shown, the first component 3, the intermediate component 4, and the second component 5 are placed on the anvil 11, and the probe 12 and the shoulder component 13 are positioned above the second surface 7. The probe 12 and the shoulder component 13 move downward so that, under the control of the control unit 16, the laminating assembly 2 is pressed against the anvil 11 by using the drive mechanism 14, in preparation for friction stir point bonding and resistance spot welding, as described below.

[0071] like Figure 10B As shown, the anvil 11 presses the first surface 6 of the laminating assembly 2 from below, and the shoulder member 13 presses the second surface 7 of the laminating assembly 2 from above. When the laminating assembly 2 is pressed between the anvil 11 and the shoulder member 13, the probe 12 rotates about the central axis and advances into the laminating assembly 2 from the side of the second surface 7.

[0072] like Figure 10C As shown, the tip of probe 12 is inserted into the second member 5, causing the second member 5 to deform, displacing material from it into the recess 25 of the shoulder member 13. Due to the frictional heat generated by rotating probe 12, the material surrounding the second member 5 becomes a plastic fluid, creating an annular plastic fluid region around probe 12. Once the tip of probe 12 reaches the intermediate member 4, control unit 16 causes current to flow between shoulder member 13 and anvil 11. The position of the tip of probe 12 can be detected or managed by the downward stroke of probe 12, the insertion pressure (insertion load) of probe 12 into laminating assembly 2, the rotational load of probe 12, or any combination thereof.

[0073] like Figure 10D As shown, when current flows between the shoulder member 13 and the anvil 11, the probe 12 continues to rotate and move further downward, and the tip of the probe 12 inserts into the intermediate member 4. As a result, the resistance heat generated in the first member 3 and the intermediate member 4 and the frictional heat generated by the rotation of the probe 12 cause a melting zone 34 to be formed in or between the first member 3 and the intermediate member 4. At the same time, a portion of the material of the second member 5 and the intermediate member 4 near the probe 12 plastically flows. In particular, the portion of the material that is further pushed away from the probe 12 is cooled and becomes relatively less fluid, but is pushed away from the probe 12 under pressure from the larger fluid portion of the material. As a result, a hook 35 is formed in the portion of the intermediate member 4 surrounding the probe 12, protruding radially outward and upward. The hook 35 thus has a crown-like shape that opens toward its front end (upper end) and extends obliquely into or weds into the material of the second member 5.

[0074] like Figure 10E As shown, control unit 16 (see...) Figure 1The current supply between the shoulder member 13 and the anvil 11 is stopped, and the probe 12 is retracted along the axis while rotating. Furthermore, the anvil 11 and the shoulder member 13 move away from the laminating assembly 2. When the current stops and the probe 12 is removed, the melting zone 34 (see...) Figure 10D The solidification forms a molten core 33, which firmly bonds the first member 3 and the intermediate member 4 together. Furthermore, since the hook 35 is formed in the second member 5 and the intermediate member 4, which have been plastically flowed by the rotation of the probe 12, the second member 5 and the intermediate member 4 are also firmly bonded together.

[0075] Figure 7 A modified embodiment of the present invention is shown, which is similar to... Figure 6 The difference in the illustrated embodiment lies in the structure of probe 12. In this modified description, corresponding components are indicated by the same reference numerals, and their descriptions are not repeated to avoid redundancy. Figure 7 In the modified embodiment shown, probe 12 extends along the central axis and has a... Figure 6 The illustrated embodiment has a similar cylindrical shape, but differs in that it includes a probe conductive portion 42 and a probe insulating portion 43 made of an electrically insulating material. The probe 41 slides in contact with the inner peripheral surface of the through-hole 20 of the shoulder member 13 at the outer peripheral surface of the probe insulating portion 43. Therefore, current flow between the probe 41 and the shoulder member 13 is prevented, thereby improving the energy efficiency of resistance welding.

[0076] Figure 8A It shows in Figure 6 The shoulder member 13 used in the illustrated embodiment, while Figures 8B to 8D Different variations are shown. Figure 8A The shoulder component 13 shown is made entirely of conductive material. Figure 8B In the case of the shoulder member 61 shown, its outer peripheral portion 62, including the flange 22 and the annular sidewall portion 23, is made of a conductive material, and its central annular portion 63, including the probe support portion 21 with the through hole 20, is made of an electrically insulating material. The second terminal 32 slides in contact with the outer peripheral surface of the conductive flange 22, and the probe 12 is electrically insulated from the flange 22 by the probe support portion 21. Figure 8CIn the case of the shoulder member 64 shown, its outer peripheral portion 66, including the flange 22 and the annular sidewall portion 23, is made of a conductive material, and its central portion, including the probe support portion 21 with the through hole 20, includes an outer ring portion 67 made of an electrically insulating material and an inner ring portion 65 made of a conductive material. Therefore, the inner ring portion 65 defining the through hole 20 is made of a conductive material such as metal, but the inner ring portion 65 is electrically insulated from the outer peripheral portion 66 of the shoulder member 64 by the outer ring portion 67. The second terminal 32 again slides in contact with the outer peripheral surface of the conductive flange 22, and the probe 12 is electrically insulated from the flange 22 by the outer ring portion 67 of the probe support portion 21. Figure 8D The shoulder component 68 shown is Figure 8C The shoulder member shown is similar, and its outer peripheral portion 69, including the flange 22 and the annular sidewall portion 23, is made of a conductive material. Its central portion, including the probe support portion 21 with the through-hole 20, includes an outer ring portion 70 made of an electrically insulating material and an inner ring portion 65 made of a conductive material. In this case, the outer ring portion 70 has an increased radial thickness to occupy a larger portion of the annular sidewall portion 23, thereby increasing the rigidity and mechanical strength of the annular sidewall portion 23 by appropriately selecting the material of the outer ring portion 70.

[0077] exist Figure 7 and Figures 8B to 8D In the modified embodiment shown, the conductive part can be made of copper alloy (e.g., chromium copper, copper with dispersed alumina, tungsten copper alloy, etc.), conductive ceramic material, hard alloy, etc., and the electrically insulating part can be made of insulating ceramic material, Bakelite (registered trademark) (phenolic resin), mica, etc.

[0078] The friction stirring engagement performed by the aforementioned engagement device 101 is a friction stirring point engagement, and the shoulder contact surface 24 of the shoulder member 13 contributes to a good appearance of the engagement point. Figure 3A Showing more details Figure 6 The shoulder member 13 of the connecting device 1 shown. By applying Figure 3B The shoulder member 13a shown, the joining device 101 of the third embodiment can be used for wire joining.

[0079] Figures 9A to 9D Different current patterns depending on the configuration of the anvil 11 are shown. The arrows in these figures indicate the flow of current. The anvil 11 and probe 12 are typically cylindrical in shape and positioned coaxially. Figure 9A The anvil 11 shown has a diameter that is substantially the same as or slightly larger than that of the probe 12. Due to the relatively small contact area between the laminating assembly 2 and the anvil 11, the laminating assembly 2 receives relatively strong and stable pressure from the anvil 11, and current flows through a relatively limited area of ​​the laminating assembly 2. Figure 9BThe anvil 11b shown has a large diameter between the inner and outer diameters of the shoulder contact surface 24 (sidewall portion 23). Because current flows through a relatively large area (relatively large radial range) of the laminating assembly 2, a relatively large melt nugget 33 is generated. Figure 9C The anvil 11c shown includes a central portion 71 and an outer peripheral portion 72. The central portion 71 is made of a material that is more rigid or harder than the outer peripheral portion 72. According to this embodiment, the deformation of the anvil 11c can be reduced when pressed against the laminate assembly 2. The outer contour of the central portion 71 can be larger than the inner contour of the shoulder contact surface 24. Figure 9D The anvil 11d shown includes a central portion 71 and an outer peripheral portion 72. The central portion 71 is made of a material with less rigidity or hardness than the outer peripheral portion 72. According to this embodiment, the outer peripheral portion 72 is preferably pressed against the laminating assembly 2, such that current preferably flows through the radially outer region (or annular region around the central axis) of the laminating assembly 2.

[0080] Figures 11A to 11C It shows the use of Figure 6 The shown coupling device 101 is used to engage with Figures 10A to 10E The joining process is performed in a slightly different manner than shown. In this case, as... Figure 11A As shown, current is supplied between the shoulder member 13 and the anvil 11 before or simultaneously with the tip of the probe 12 contacting the second surface 7 of the laminating assembly 2. Because resistive heat generated by the current is produced over a wider area of ​​the laminating assembly 2 (the region of the second member 5 adjacent to the probe 12 and the shoulder member 13), and the size of the portion of the second member 5 softened by resistive heat increases, the probe 12 can be inserted into the laminating assembly with lower resistance and / or at a higher speed. Figure 11B As shown, when current is supplied immediately before the tip of probe 12 reaches the intermediate member 4 of the laminating assembly 2, resistive heating softens the portion of the second member extending from the outer periphery of the probe (generating the hook 35 from the outer periphery to the shoulder contact surface 24), allowing the tip of the hook 35 to be guided radially outward (for better anchoring of the hook 35). Furthermore, the portion of the intermediate member 4 located directly above the anvil 11 is actively softened, thereby actively generating the hook 35 and preventing softened material from flowing into the interface between the first member 3 and the intermediate member 4. Figure 11C This illustrates the case where current supply begins when the tip of probe 12 has advanced beyond the interface between the second member 5 and the intermediate member 4. In this case, a similar current supply can be obtained from... Figure 11B The advantages obtained from the implementation shown are as follows.

[0081] The various features and advantages of the aforementioned embodiments will now be discussed.

[0082] In the aforementioned joining device 101, the anvil 11 and probe 12 used for friction stir bonding can also be used as electrodes for resistance spot welding. Compared to using a friction stir bonding device and a resistance spot welding device separately, the cost and size of the joining device 1 can be minimized. In particular, by using the aforementioned joining device 1, the length of the production line can be reduced, and the necessary investment can be decreased. Furthermore, since friction stir bonding and resistance spot welding can be performed simultaneously, the time required for the manufacturing process can be reduced.

[0083] When resistance welding dissimilar materials, very brittle intermetallic compounds are often formed, resulting in a failure to achieve the desired bond strength. In the above embodiment, since the second component 5 and the intermediate component 4, which may be made of different materials, are joined by friction stir bonding instead of resistance welding, this reduction in bond strength due to intermetallic compounds is prevented.

[0084] In the above embodiment, the frictional heat generated by the probe 12 during the friction-stirring bonding of the intermediate component 4 and the first component 3 facilitates the resistance welding of the intermediate component 4 and the first component 3, thereby reducing the energy consumption of resistance welding. In resistance welding, it is known that if the molten region 34 cools too quickly, the toughness of the weld nugget 33 may decrease. In the aforementioned embodiment, since the probe 12 remains rotating and is pulled out from the lamination assembly 2 after the current for resistance welding is stopped, the frictional heat generated by the probe 12 is conducted to the molten region 34, thereby preventing the molten region 34 from cooling rapidly and preventing a decrease in the toughness of the weld nugget 33.

[0085] exist Figure 7 , Figures 8B to 8D In the illustrated embodiment, a probe insulating portion 43, a central annular portion 63, and an outer annular portion 67, all made of electrically insulating material, are used. The probe 12 (41) is electrically insulated from the outer periphery of the shoulder member 13, which is connected to the power supply 15 via a second terminal 32. Therefore, the electrical safety measures for the coupling device 1 can be simplified. Figure 8C In the embodiment shown, the shoulder member 68 includes an inner ring portion 65 that can conduct electricity and can be made of a highly wear-resistant metal material.

[0086] In the first to third embodiments and their variations, the anvil 11 (see Figure 1 (etc.) can be changed to Figure 12 or Figure 14A Anvils 111 and 121 are shown.

[0087] Figure 12 and Figure 13A and Figure 13BThe anvil 111 shown has a cylindrical shape and is provided with an anvil contact surface 112 supporting the first surface 6 of the laminate assembly 2. The anvil contact surface 112 includes an electrically insulating region 113 and an annular conductive region 114 surrounding the electrically insulating region 113. The electrically insulating region 113 is centrally located in a circular shape around the central axis of the anvil 111. The diameter of the electrically insulating region 113 is preferably 2 mm or greater. The electrically insulating region 113 does not need to be circular, but may also have a polygonal or other irregular shape. Similarly, the conductive region 114 does not need to have a circular annular shape, but may have any other shape. The anvil 111 extends from the conductive region 114 to the connection portion of the first terminal 31 (see...). Figure 1 The part needs to be conductive.

[0088] like Figure 13A and Figure 13B As shown, current can flow between the conductive area 114 of the anvil 111 and the probe 12. Figure 13A ) or shoulder component 13 ( Figure 13B Conduction occurs between them. In either case, the weld nugget 115 is formed in an annular shape. If the bonding areas are equal to each other, the annular weld nugget 115 has a greater bonding strength than the circular weld nugget 33 (see [link to documentation]). Figures 2A to 2C A larger outer diameter results in increased bond strength, particularly with respect to peel load.

[0089] In current such Figure 13B As shown, when the current passes between the anvil 11 and the shoulder member 13, the current is as follows: Figure 13A Compared to the case shown where the current passes between the anvil 11 and the probe 12, the current path extends radially outward, allowing for an increase in the outer diameter of the molten core 115 and an increase in bonding strength. For example... Figure 12 The anvil 111 shown, including a circular electrically insulating region 113 and an annular conductive region 114, can be compared to Figure 14A The anvil 121 shown is manufactured at a lower cost, which will be discussed below.

[0090] Figure 14A The anvil 121 shown includes an anvil contact surface 122 supporting the first surface 6 of the laminate assembly 2. The anvil contact surface 122 includes a cross-shaped insulating region 123 and four fan-shaped conductive regions 124 separated from each other by the insulating region 123. The center of the cross-shaped insulating region 123 coincides with the central axis of the probe 12. The insulating region 123 need not be cross-shaped, as long as the conductive regions 124 are divided into multiple mutually isolated or separated portions. For example, the insulating region 123 may consist of multiple strips extending radially from the center, or it may consist of multiple strips extending in both vertical and horizontal directions.

[0091] Current flows from probe 12 or shoulder member 13 to conductive region 114 of anvil 111. Using anvil 121 with cross-shaped insulating regions 123, the current is split and flows to four isolated conductive regions 124. Therefore, as... Figure 14B As shown, four island-shaped melt nuggets 125 are formed, isolated from each other. Since the melt nuggets 125 are dispersed and each melt nugget is formed as an island, the stress generated during bonding can be dispersed. Furthermore, since the current density is increased compared to the case where no insulating region 123 is provided, the melting of the first member 3 and the intermediate member 4 is promoted, thereby more advantageously generating the melt nuggets 125 while reducing power consumption.

[0092] The invention has been described with reference to specific embodiments, but the invention is not limited to these embodiments and can be modified in various ways without departing from the scope of the invention. The joining between the second member and the intermediate member can be resistance welding other than spot welding. Different features of various embodiments can be combined without departing from the scope of the invention. For example, Figure 3B The shoulder component shown can be applied to Figure 6 The coupling device 101 shown. In Figure 10D In this process, the timing of supplying current between the shoulder member 13 and the anvil 11 can be selected as the time point when the probe 12 arrives at the first member 3 or immediately thereafter. Therefore, an annular weld nugget 33 can be generated in a stable manner, and the bonding strength can be increased.

Claims

1. A joining device for joining a first component, an intermediate component, and a second component together, the first component, the intermediate component, and the second component being conductive, extending along a defined main plane, and stacked in this order as a laminated assembly, the joining device comprising: An anvil, the anvil having an anvil contact surface for supporting the first surface of the laminate assembly provided by the first member, the anvil contact surface including an electrically insulating region and a conductive region; A probe, which is positioned opposite a second surface of the laminate provided by the second member at a location corresponding to the probe, and is configured to rotate about a central axis intersecting the main plane and move toward and away from the second member; An electrical conductor configured to contact the second surface of the laminated assembly; A drive mechanism configured to rotate the probe about the central axis and to move the probe toward and away from the second member along the central axis; A power source electrically connected to the anvil and the electrical conductor to conduct current through the lamination assembly via the anvil and the electrical conductor; as well as The control unit is used to control the operation of the drive mechanism and the power supply. The control unit is configured to rotate the probe about the central axis and advance it from the side of the second surface into the laminate assembly. Once the tip of the probe reaches the intermediate member, the control unit causes current to flow between the probe and the anvil, such that the first member and the intermediate member are joined together by resistance welding, and the second member and the intermediate member are joined together by friction stirring.

2. The coupling device according to claim 1, wherein, The probe is the electrical conductor.

3. The coupling device according to claim 1, further comprising a shoulder member having a through-hole for receiving the probe and a shoulder contact surface configured to abut against the second surface, the shoulder member being at least partially conductive, wherein, The shoulder member is the electrical conductor.

4. The coupling device according to claim 3, wherein, The shoulder member is provided with a recess that is recessed relative to the shoulder contact surface to define a bottom surface opposite the second surface and to partially receive the probe.

5. The coupling device according to claim 1, wherein, The electrically insulating region is centrally located on the contact surface of the anvil.

6. The coupling device according to claim 5, wherein, The conductive region is arranged in a ring shape around the electrically insulating region on the contact surface of the anvil.

7. The coupling device according to claim 1, wherein, The conductive region is provided as multiple segments on the contact surface of the anvil, and the multiple segments are isolated and separated from each other by a portion of the electrically insulating region.

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