JP2006159277A - Ultrasonic welding method, ultrasonic welding equipment, and conductor unit - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide an ultrasonic welding method, an ultrasonic welding equipment, and a conductor unit capable of preventing short circuit with other electric components, and constituting first and second metals from a material weak against the heat. <P>SOLUTION: The ultrasonic welding equipment 10 has an ultrasonic welding machine 11 and a cooling mechanism 12. The ultrasonic welding machine 11 has a chip 14 and an anvil 15 to hold a metal piece 2 and a core wire 7 with a plated layer 6 formed therebetween. The cooling mechanism 12 cools the metal piece 2 and the core wire 7 held between the chip 14 and the anvil 15. In the ultrasonic welding equipment 10, the core wire 7 overlaps the plated layer 6, the metal piece 2 and the core wire 7 are held between the chip 14 and the anvil 15, and cooled by the cooling mechanism 12 while the ultrasonic welding machine 11 gives ultrasonic vibration of the intensity at which the plated layer 6 is melted. <P>COPYRIGHT: (C)2006,JPO&NCIPI

Description

  The present invention relates to a metal having a plating layer made of tin or a tin alloy, an ultrasonic welding method for joining another metal, an ultrasonic welding apparatus, a metal having a plating layer made of tin or a tin alloy, and the like. The present invention relates to a conductor unit including other metals.

  For example, a wire harness routed in an automobile or the like includes an electric wire and a terminal fitting as a first metal attached to an end portion of the electric wire. The said electric wire is provided with the core wire as a 2nd metal which consists of metals, such as copper, and the insulating coating | coated part which coat | covers this core wire. In the terminal fitting, a plating layer made of tin or the like is formed on the surface of a base material made of a conductive metal.

  Conventionally, when the terminal fitting and the electric wire are electrically and mechanically connected, a part of the terminal fitting is caulked to the electric wire. For this reason, for example, when the wire harness is routed in an automobile or the like, there is a risk that the electrical connection between the terminal fitting and the electric wire is broken due to vibration or the like while the automobile is running.

For this reason, it has been proposed to heat the terminal metal fitting and the core wire of the electric wire and to join them together by so-called ultrasonic welding to reliably connect the terminal metal fitting and the electric wire. (For example, refer to Patent Document 1).
JP-A-9-168876

  However, in the ultrasonic welding method disclosed in Patent Document 1 described above, the plating layer containing tin or tin alloy is once melted, and the molten plating layer is removed from between the base material and the core wire. The base material and the core wire are so-called ultrasonic welded. For this reason, in the method shown in Patent Document 1, the molten plating layer sometimes spreads outside the base material along the surface of the base material. As described above, there is a possibility that the molten plating layer spreads outside the base material as if it is a burr and comes into contact with other electrical parts such as other terminal fittings. As described above, when the ultrasonic welding method disclosed in Patent Document 1 described above is used, there is a fear that electrical components are short-circuited.

  In addition, since the ultrasonic welding method disclosed in Patent Document 1 described above performs ultrasonic welding while heating the terminal fitting and the core wire of the electric wire, the base metal of the terminal fitting and the core wire of the electric wire are formed from a material that is weak against heat. I couldn't.

  Accordingly, an object of the present invention is to provide an ultrasonic welding method, an ultrasonic welding apparatus, and a conductor unit that can prevent a short circuit with other electrical components and the like and can constitute the first and second metals from a heat-sensitive material. Is to provide.

  In order to solve the problems and achieve the object, the ultrasonic welding method of the present invention according to claim 1 is different from the first metal in which a plating layer is formed on the surface of a base material and the first metal. In the ultrasonic welding method for joining the second metal of the body, the plating is performed by pressing the first metal and the second metal close to each other, overlapping the second metal on the plating layer of the first metal. The second metal and the plating layer are joined while cooling the base material, the plating layer, and the second metal by applying ultrasonic vibration that melts the layer.

  The ultrasonic welding method according to a second aspect of the present invention is the ultrasonic welding method according to the first aspect, wherein the plating layer includes tin or a tin alloy, and the second metal includes aluminum or an aluminum alloy. It is characterized by including.

  According to a third aspect of the present invention, there is provided an ultrasonic welding apparatus for joining a first metal having a plating layer formed on a surface of a base material and a second metal separate from the first metal. In the welding apparatus, the second metal is superposed on the plating layer of the first metal, and the first metal and the second metal are pressed in a direction approaching each other, and an ultrasonic vibration that melts the plating layer is applied. An ultrasonic vibration applying means, and a cooling mechanism for cooling the base material, the plating layer, and the second metal, and the ultrasonic vibration applying means pressurizes the first metal and the second metal in a direction to bring them close to each other. It is characterized in that the cooling mechanism joins the second metal and the plating layer while applying sound wave vibration and cooling the base material, the plating layer and the second metal.

  The conductor unit of the present invention according to claim 4 includes a first metal having a plating layer formed on a surface of a base material, and a second metal separate from the first metal, and the plating layer; In the conductor unit in which the second metal is joined, the second metal is superimposed on the plating layer of the first metal, and the plating is melted by pressing the first metal and the second metal toward each other. The second metal and the plating layer are bonded to each other while cooling the base material, the plating layer, and the second metal.

  According to the ultrasonic welding method of the present invention described in claim 1, since the ultrasonic vibration that melts the plating layer while cooling is applied, the plating is performed during the ultrasonic welding while applying the ultrasonic vibration. It is possible to regulate the melting of the layer, and the molten plating layer is immediately solidified.

  According to the ultrasonic welding method of the present invention described in claim 2, since the plating layer includes tin or a tin alloy and the second metal includes aluminum or an aluminum alloy, the bonding between the plating layer and the second metal is performed. An intermetallic compound is not formed at a location. In addition, the aforementioned tin or tin alloy and the alloy containing aluminum or aluminum alloy are formed by plastic flow when ultrasonic vibration is applied to the above-described joint.

  According to the ultrasonic welding apparatus of the present invention as set forth in claim 3, the ultrasonic vibration applying means applies ultrasonic vibration that melts the plating layer while the cooling mechanism cools. For this reason, while the ultrasonic vibration is applied, that is, it is possible to regulate the melting of the plating layer during ultrasonic welding, and the molten plating layer is immediately solidified.

  According to the conductor unit of the present invention described in claim 4, while being cooled, ultrasonic vibration that melts the plating layer is applied, and the plating layer and the second metal are joined. For this reason, while the ultrasonic vibration is applied, that is, the plating layer is restricted from melting during ultrasonic welding, and the molten plating layer is immediately solidified.

  As described above, the present invention described in claim 1 can regulate the melting of the plating layer during ultrasonic welding while applying ultrasonic vibration, and immediately solidifies the molten plating layer. be able to. For this reason, it can prevent that a plating layer spreads on the outer side of a base material. Therefore, it can prevent that the plating layer joined with the 2nd metal contacts other electrical components, and is short-circuited with the other electrical components.

  Moreover, since the ultrasonic vibration of the intensity | strength which a plating layer fuse | melts is provided, a plastic flow arises in a joining location and a plating layer and a 2nd metal mix without forming an intermetallic compound. For this reason, the joint strength between the plating layer and the second metal can be increased.

  Furthermore, since ultrasonic welding is performed while cooling, it is possible to prevent the temperature of the plating layer and the like from rising excessively. Therefore, a plating layer, a base material, and a 2nd metal can be comprised from a metal with low heat resistance.

  The present invention according to claim 2 is an alloy containing tin or a tin alloy and aluminum or an aluminum alloy by plastic flow or the like at the joining location without forming an intermetallic compound at the joining location between the plating layer and the second metal. Is formed. Therefore, the bonding strength between the plating layer and the second metal can be increased.

  According to the third aspect of the present invention, while the ultrasonic vibration is applied, it is possible to regulate the melting of the plating layer during ultrasonic welding, and it is possible to immediately solidify the molten plating layer. For this reason, it can prevent that a plating layer spreads on the outer side of a base material. Therefore, it can prevent that the plating layer joined with the 2nd metal contacts other electrical components, and is short-circuited with the other electrical components.

  Moreover, since the ultrasonic vibration of the intensity | strength which a plating layer fuse | melts is provided, a plastic flow arises in a joining location and a plating layer and a 2nd metal mix without forming an intermetallic compound. For this reason, the joint strength between the plating layer and the second metal can be increased.

  Furthermore, since ultrasonic welding is performed while cooling, it is possible to prevent the temperature of the plating layer and the like from rising excessively. Therefore, a plating layer, a base material, and a 2nd metal can be comprised from a metal with low heat resistance.

  In the present invention described in claim 4, while the ultrasonic vibration is applied, that is, the plating layer is restricted from melting during ultrasonic welding, and the molten plating layer is immediately hardened. For this reason, it can prevent that a plating layer spreads on the outer side of a base material. Therefore, it can prevent that the plating layer joined with the 2nd metal contacts other electrical components, and is short-circuited with the other electrical components.

  In addition, since ultrasonic vibration having such a strength that the plating layer is melted is applied, plastic flow occurs at the joining portion, and the plating layer and the second metal are mixed without forming an intermetallic compound. For this reason, the joint strength between the plating layer and the second metal can be increased.

  Furthermore, since ultrasonic welding is performed while cooling, it is possible to prevent the temperature of the plating layer and the like from rising excessively. Therefore, a plating layer, a base material, and a 2nd metal can be comprised from a metal with low heat resistance.

  Hereinafter, an embodiment of the present invention will be described with reference to FIGS. In the first embodiment, the conductor module 1 shown in FIG. 1 is assembled. As shown in FIG. 1, the conductor module 1 includes a metal piece 2 as a first metal and a covered electric wire 3.

  The metal piece 2 includes a plate-like base material 5 and a plating layer 6 formed on one or both surfaces of the base material 5 and is formed in a relatively thin thin plate shape. The base material 5 is made of a conductive metal. In the illustrated example, the base material 5 is made of brass. The plating layer 6 is made of (or contains) tin or a tin alloy. In the illustrated example, the plating layer 6 is made of (includes) tin.

  The covered electric wire 3 has a round cross section. The covered electric wire 3 includes a core wire 7 as a second metal having a round cross section and a covering portion 8 that covers the core wire 7. The core wire 7 is of course separate from the metal piece 2. The core wire 7 is made of (including) a conductive metal. The core wire 7 is formed by twisting one conductive strand or a plurality of conductive strands.

  The core wire 7 has flexibility. The wire rule, ie, the core wire 7 is made of (or contains) aluminum or an aluminum alloy. In the example of illustration, the strand which comprises the core wire 7 consists of (includes) an aluminum alloy. The covering portion 8 is made of a synthetic resin having insulating properties and flexibility.

  In the conductor module 1, the plating layer 6 of the metal piece 2 and the core wire 7 are joined to each other with the core wire 7 overlapping the plating layer 6 of the metal piece 2. At this time, in the joint portion S between the plating layer 6 and the core wire 7, an alloy G containing tin that constitutes the plating layer 6 and an aluminum alloy that constitutes the core wire 7 is formed as shown in FIG. 2. In addition, an intermetallic compound of tin that constitutes the plating layer 6 and an aluminum alloy that constitutes the core wire 7 is not formed in the joint portion S. The joint S described above is formed by applying ultrasonic vibration with a strength that the plating layer 6 melts to the core wire 7, the plating layer 6, and the base material 5 through the chip 14 described later while being cooled. Yes.

  The conductor module 1 is obtained by joining the plating layer 6 of the metal piece 2 and the core wire 7 to each other by an ultrasonic welding apparatus 10 (shown in FIG. 3). As shown in FIG. 3, the ultrasonic welding apparatus 10 includes an ultrasonic welding machine 11 as an ultrasonic vibration applying unit, a cooling mechanism 12, and a control unit 13 as a control unit.

  As shown in FIG. 3, the ultrasonic welder 11 includes a tip 14 (also referred to as a tool horn), an anvil 15 opposed to the tip 14, an oscillator (not shown), a vibrator, a horn 16, and the like. Yes.

  The ultrasonic welder 11 sandwiches an object to be welded between the tip 14 and the anvil 15 and presses the tip 14 and the anvil 15 close to each other, and presses the vibrator with an oscillator. This vibration (also referred to as ultrasonic vibration) is transmitted to the chip 14 via the horn 16. Then, the ultrasonic welder 11 applies ultrasonic vibration to the welding object sandwiched between the tip 14 and the anvil 15 to weld the objects.

  The cooling mechanism 12 includes a coolant spraying device 17 and a coolant circulation device 18. The coolant spraying device 17 includes a coolant supply source 19 and a plurality of nozzles 20 (only one is shown in FIG. 3). The coolant supply source 19 contains a cooled coolant such as a gas such as air and supplies the coolant into the nozzle 20 described above. The nozzle 20 sprays the coolant supplied from the coolant supply source 19 onto the tip of the chip 14. The coolant spraying device 17 sprays coolant from the nozzle 20 to the tip of the tip 14 to cool the core wire 7, the plating layer 6 and the base material 5 sandwiched between the tip 14 and the anvil 15.

  The coolant circulation device 18 includes a pipe 21, a refrigerant tank 22, an expansion valve 23, a compressor 24, and a heat exchanger 25. A part of the pipe 21 is attached to the anvil 15. The pipe 21 connects the above-described refrigerant tank 22, the expansion valve 23, the compressor 24, and the heat exchanger 25 in series. The refrigerant tank 22 stores the refrigerant cooled by the heat exchanger 25. The expansion valve 23 expands and cools the refrigerant in the refrigerant tank 22 and sends the refrigerant to the compressor 24 through a portion attached to the anvil 15 of the pipe 21.

  The refrigerant in the pipe 21 flows from the expansion valve 23 toward the compressor 24, deprives the anvil 15 of heat, and is heated. That is, the refrigerant in the pipe 21 cools the anvil 15. The compressor 24 compresses and liquefies the refrigerant heated by the anvil 15 and sends it out to the heat exchanger 25. The heat exchanger 25 cools the refrigerant liquefied by the compressor 24 and sends it out to the refrigerant tank 22.

  The coolant circulating device 18 described above circulates the refrigerant in the pipe 21 in order through the refrigerant tank 22, the expansion valve 23, the compressor 24, and the heat exchanger 25 to cool the anvil 15, whereby the chip 14 and the anvil 15 are circulated. The base material 5, the plating layer 6 and the core wire 7 sandwiched between are cooled.

  In the cooling mechanism 12 described above, the coolant spraying device 17 sprays coolant on the tip of the tip 14, and the coolant circulating device 18 cools the anvil 15, and the base material 5 sandwiched between the tip 14 and the anvil 15, The plating layer 6 and the core wire 7 are cooled.

  The control device 13 is a computer including a known RAM, ROM, CPU, and the like. The control device 13 is connected to the ultrasonic welding machine 11 and the cooling mechanism 12, and controls the entire ultrasonic welding device 10 by controlling these operations. The control device 13 described above uses ultrasonic waves so that the force that presses the tip 14 and the anvil 15 closer to each other, the amplitude and frequency of ultrasonic vibration, the vibration time, and the like have values that cause the plating layer 6 to melt. The welding machine 11 is controlled. In other words, the control device 13 causes the ultrasonic welder 11 to apply ultrasonic vibration that melts the plating layer 6.

  Further, the control device 13 stores a pattern in which the coolant spraying device 17 of the cooling mechanism 12 described above sprays the coolant and a pattern in which the coolant circulation device 18 circulates the refrigerant, and according to these previously stored patterns. The coolant spraying device 17 and the coolant circulation device 18 are operated to cool the base material 5, the plating layer 6 and the core wire 7 sandwiched between the chip 14 and the anvil 15.

  When the conductor module 1 is assembled, that is, when the plating layer 6 of the metal piece 2 and the core wire 7 are fixed, a part of the covering portion 8 is removed in advance to expose a part of the core wire 7. In the illustrated example, the covering portion 8 located at the end 3a of the covered electric wire 3 is removed.

  Then, as shown in FIG. 3, the metal piece 2 is overlaid on the anvil 15 so that the plating layer 6 faces the chip 14. The exposed core wire 7 is superimposed on the plating layer 6 of the metal piece 2. The tip surface of the chip 14 is brought into contact with the core wire 7. Thus, the metal piece 2, the plate member 4, and the core wire 7 are sandwiched between the tip 14 and the anvil 15.

  Then, after pressurizing the chip 14 and the anvil 15 toward each other, the vibrator is vibrated by an oscillator and this vibration is transmitted to the chip 14 via a horn. Then, the chip | tip 14 vibrates, for example along the arrow K in FIG. The arrow K is orthogonal to the direction in which the tip 14 and the anvil 15 face each other, and is parallel to the surface of the metal piece 2.

  As shown in FIG. 4, the control device 13 causes the ultrasonic welding machine 11 to apply the ultrasonic vibration that melts the plating layer 6 described above to the core wire 7 described above. Further, the control device 13 causes the cooling mechanism 12 to cool the base material 5, the plating layer 6, and the core wire 7 sandwiched between the chip 14 and the anvil 15. In this way, ultrasonic vibration having such a strength that the plating layer 6 melts is applied to the base material 5, the plating layer 6, and the core wire 7 sandwiched between the chip 14 and the anvil 15 while being cooled.

  Then, the vibration described above occurs between the core wire 7 and the plating layer 6. And even if a part of the plating layer 6 is about to melt, it is cooled by the cooling mechanism 12, so that it is difficult to melt and the molten plating layer 6 is cooled by the cooling mechanism 12, so that it hardens immediately. For this reason, the tin which comprises the plating layer 6 mentioned above, and the aluminum alloy which comprises the core wire 7 raise | generate a plastic flow or a diffusion phenomenon, and mutually mix. In this way, the metal layer 2 and the core wire 7 are metal-bonded.

  Thus, the plating layer 6 and the core wire 7 of the metal piece 2 are bonded to each other by so-called ultrasonic welding (also referred to as ultrasonic welding or ultrasonic bonding). And the conductor module 1 of the structure mentioned above is obtained.

  Next, the inventor of the present invention photographed a cross section of the joint portion of the conductor module 1 obtained by the above-described metal-to-metal joining method with a scanning electron microscope. The photographed results are shown in FIGS. FIG. 5 is a diagram schematically showing an image obtained by actually capturing the image shown in FIG. In FIG. 5, the same parts as those in FIG. Further, the portion shown in light gray in FIG. 6 shows the core wire 7 of the covered electric wire 3 made of an aluminum alloy, and the portion that appears whitish in FIG. 6 constitutes the aluminum alloy and the plating layer 6 constituting the core wire 7. An alloy with tin is shown.

  As shown in FIGS. 5 and 6, a portion in which an alloy G made of aluminum alloy and tin is formed between the core wire 7 made of aluminum alloy and a plating layer 6 made of tin, and the alloy G is not formed. Then, the core wire 7 made of an aluminum alloy and the plating layer 6 made of tin are in close contact. For this reason, it became clear from the image obtained with the scanning electron microscope mentioned above that the plating layer 6 of the metal piece 2 and the core wire 7 were reliably joined metallically.

  According to this embodiment, since the ultrasonic vibration that melts the plating layer 6 is applied while cooling, it is possible to regulate melting of the plating layer 6 during ultrasonic welding while applying ultrasonic vibration. At the same time, the molten plating layer 6 immediately hardens. For this reason, the plating layer 6 can be prevented from spreading to the outside of the base material 5. Therefore, it is possible to prevent the plating layer 6 joined to the core wire 7 from coming into contact with another electrical component and short-circuiting with the other electrical component.

  In addition, since ultrasonic vibration having such a strength that the plating layer 6 is melted is applied, plastic flow is generated at the joining portion S, and the plating layer 6 and the core wire 7 as the second metal are mixed without forming an intermetallic compound. . For this reason, the joint strength between the plating layer 6 and the core wire 7 can be increased.

  Furthermore, since ultrasonic welding is performed while cooling, it is possible to prevent the temperature of the plating layer 6 and the like from rising excessively. Therefore, the plating layer 6, the base material 5, and the core wire 7 can be comprised from a metal with low heat resistance.

  Moreover, since the plating layer 6 includes tin and the core wire 7 includes an aluminum alloy, an intermetallic compound is not formed at the joint portion S between the plating layer 6 and the core wire 7. In addition, the alloy G containing the above-described tin and aluminum alloy is formed by plastic flow or the like when the ultrasonic vibration is applied to the above-described joining portion S. Therefore, the bonding strength between the plating layer 6 and the core wire 7 can be increased.

  Next, the inventors of the present invention actually ultrasonically welded the core wire 7 of the covered electric wire 3 to the metal piece 2 on which the plating layer 6 was formed, and confirmed the effect of the present invention. The results are shown in FIGS. In the product of the present invention indicated by a solid line and an alternate long and short dash line in FIG. 7 and indicated by a solid line in FIG. 8, the core wire 7 of the covered wire 3 and the plating layer 6 of the metal piece 2 are formed by the ultrasonic welding apparatus 10 described in the above-described embodiment. Were ultrasonically welded.

  In the product of the present invention described above, the core wire 7 and the metal piece 2 are pressed in a direction to bring them close to each other, and the ultrasonic vibration having such a strength that the plating layer 6 is melted is applied for a time during which the plating layer 6 is melted. . In the product of the present invention, the cooling mechanism 12 described above is operated between the tip 14 and the anvil 15 before the ultrasonic vibration is stopped until the plating layer 6 is melted after the ultrasonic vibration is started. The base material 5, the plating layer 6 and the core wire 7 sandwiched between the two are cooled. In this way, in the product of the present invention, ultrasonic vibration having such a strength that the plating layer 6 is melted is applied.

  Further, in the comparative example shown by the dotted line in FIG. 8, the ultrasonic vibration is applied so that the core layer 7 and the metal piece 2 are pressed in the direction close to each other with the same strength as the product of the present invention and the above-described plating layer 6 is not melted. Is given for the same time as the product of the present invention described above. Thus, in the comparative example, the ultrasonic vibration having such a strength that the above-described plating layer 6 does not melt is applied to the core wire 7, the plating layer 6, and the base material 5.

  Furthermore, in both the product of the present invention and the comparative example described above, the core wire 7 is made of an aluminum alloy, the outer diameter of the core wire 7 is 1.0 mm, the plating layer 6 is made of tin, and the plating layer 6 The thickness was 2.5 mm, the base material 5 was made of brass, and the thickness of the base material 5 was 0.3 mm.

  The solid line in FIG. 7 indicates the bonding strength with respect to the time during which each ultrasonic welding is performed when ultrasonic welding is performed under the above-described conditions. Note that the bonding strength is determined by peeling the core wire 7 and the plating layer 6 along the arrows K1 and K2 in FIG. 2 orthogonal to the surface of the metal piece 2, that is, the base material 5 after the ultrasonic welding is completed. In this case, it is a force when the core wire 7 and the plating layer 6 are separated. In addition, when the core wire 7 and the plating layer 6 are joined and separated from each other, the joint strength is 100% when the core wire 7 made of an aluminum alloy is broken.

  Moreover, the dashed-dotted line in FIG. 7 has shown the change of the temperature of the junction location at the time of ultrasonic welding on the conditions mentioned above. In addition, the temperature of a junction location was measured by making a known thermocouple contact the vicinity of a junction location, or measuring the radiant heat from a junction location.

  Furthermore, the product of the present invention indicated by the solid line in FIG. 8 and the comparative example indicated by the dotted line indicate the bonding strength with respect to the time during which each ultrasonic welding was performed when ultrasonic welding was performed under the above-described conditions. Moreover, the joining time which is a horizontal axis in FIG.7 and FIG.8 has shown the time which provided the ultrasonic vibration, and the temperature of the joining location S is melting | fusing point of the tin which comprises the plating layer 6 by this invention product. The time to reach 232.4 ° C. is set to 100%.

  According to FIG. 7, in the product of the present invention, when the joining time is 100% after the start of application of ultrasonic vibration, the temperature of the joining portion S is 232.4 ° C., which is the melting point of tin constituting the plating layer 6. It is over. For this reason, it became clear that the plated layer 6 starts to melt in the product of the present invention when the joining time reaches 100% after the start of application of ultrasonic vibration.

  Further, according to the comparative example in FIG. 8, the bonding strength was about 25% at the maximum. In other words, it has been clarified that the plating layer 6 and the core wire 7 cannot be bonded with sufficient bonding strength even when ultrasonic vibration having such a strength that the plating layer 6 does not melt is applied.

  Moreover, according to the product of the present invention in FIGS. 7 and 8, it became clear that the bonding strength of the product of the present invention approaches 100%. In other words, by applying ultrasonic vibration with such a strength that the plating layer 6 melts while cooling, the bonding strength approaches that of the aluminum alloy itself, and the plating layer 6 and the core wire 7 can be bonded with sufficient bonding strength. Became clear.

  In embodiment mentioned above, the case where the core wire 7 of the covered electric wire 3 is joined to the metal piece 2 is shown. However, in the present invention, it is needless to say that not only the core wire 7 of the covered electric wire 3 but also various conductive metals may be joined to the metal piece 2. Further, the metal piece 2 of the above-described embodiment may constitute a terminal fitting used for a wire harness such as an automobile.

  Furthermore, in this invention, as shown in FIG. 9, the 3rd metal 30 is further piled up on the core wire 7 as a 2nd metal, the plating layer 6 of the metal piece 2 as a 1st metal, and the core wire 7 as a 2nd metal. May be joined by ultrasonic welding, and the core wire 7 and the third metal 30 as the second metal may be joined by ultrasonic welding. In FIG. 9, the same parts as those of the above-described embodiment are denoted by the same reference numerals and description thereof is omitted.

  In the above-described embodiment, the coolant spraying device 17 and the coolant circulation device 18 of the cooling mechanism 12 are operated according to the pattern stored in advance in the control device 13, and are sandwiched between the chip 14 and the anvil 15. The core wire 7 and the metal piece 2 are cooled. However, in the present invention, the temperature of the core wire 7 and the metal piece 2 sandwiched between the chip 14 and the anvil 15 is detected by using a temperature detection means such as a thermocouple, and based on the detected temperature. The control device 13 may control the coolant spraying device 17 and the coolant circulation device 18 to cool the core wire 7 and the metal piece 2 sandwiched between the tip 14 and the anvil 15. In short, the cooling mechanism 12 may cool the core wire 7 and the metal piece 2 to which the ultrasonic vibration is applied in various patterns. Further, the cooling mechanism 12 may use a known Peltier element or the like.

  In addition, embodiment mentioned above only showed the typical form of this invention, and this invention is not limited to embodiment. That is, various modifications can be made without departing from the scope of the present invention.

It is a perspective view which shows the conductor module assembled with the ultrasonic welding method concerning one Embodiment of this invention. It is sectional drawing along the II-II line | wire in FIG. It is explanatory drawing which shows the structure of the ultrasonic welding apparatus used when assembling the conductor module shown by FIG. It is explanatory drawing which shows the state which the ultrasonic welding apparatus shown by FIG. 3 assembles a conductor module. It is a figure which shows typically the result obtained by imaging the junction location of the conductor module shown by FIG. 1 with a scanning electron microscope. It is a figure which shows the result obtained by imaging the joining location of the conductor module shown by FIG. 1 with a scanning electron microscope. It is explanatory drawing which shows the change of the joint strength in ultrasonic welding of this invention goods, and the change of the temperature of a joining location. It is explanatory drawing which shows the change of the joining strength in ultrasonic welding of this invention product and a comparative example. It is explanatory drawing which shows the other usage method of the ultrasonic welding apparatus shown by FIG.

Explanation of symbols

1 Conductor Module 2 Metal Piece (First Metal)
5 Base material 6 Plating layer 7 Core wire (second metal)
10 Ultrasonic welding equipment 11 Ultrasonic welding machine (Ultrasonic vibration applying means)
12 Cooling mechanism

Claims (4)

In an ultrasonic welding method for joining a first metal having a plating layer formed on the surface of a base material and a second metal separate from the first metal,
Superposing the second metal on the plating layer of the first metal, applying pressure in a direction in which the first metal and the second metal are brought close to each other, and applying ultrasonic vibration to melt the plating layer, An ultrasonic welding method comprising joining the second metal and the plating layer while cooling the plating layer and the second metal. The plating layer includes tin or a tin alloy,
The ultrasonic welding method according to claim 1, wherein the second metal includes aluminum or an aluminum alloy. In an ultrasonic welding apparatus for joining a first metal having a plating layer formed on a surface of a base material and a second metal separate from the first metal,
The ultrasonic vibration applying means for applying the ultrasonic vibration that melts the plating layer by applying the second metal on the plating layer of the first metal and pressurizing the first metal and the second metal in a direction approaching each other. When,
A cooling mechanism for cooling the base material, the plating layer, and the second metal,
The ultrasonic vibration applying means pressurizes the first metal and the second metal in a direction approaching each other to apply ultrasonic vibration, and the cooling mechanism cools the base material, the plating layer, and the second metal, An ultrasonic welding apparatus for joining a second metal and the plating layer. In a conductor unit comprising: a first metal having a plating layer formed on a surface of a base material; and a second metal separate from the first metal, wherein the plating layer and the second metal are joined.
Superposing the second metal on the plating layer of the first metal, pressing the first metal and the second metal in a direction approaching each other, and applying ultrasonic vibration that melts the plating layer, the base material, A conductor unit in which the second metal and the plating layer are joined while cooling the plating layer and the second metal.