JP4479416B2 - Friction spot welding method and apparatus - Google Patents

Description

  The present invention relates to a method for joining dissimilar metal materials, and more particularly, to a friction point joining method and apparatus for performing joining by softening, stirring, and generating plastic flow by using frictional heat generated by a rotor.

  In recent years, with the trend of reducing the weight of automobile bodies, the need for joining aluminum alloys in place of ferrous materials is increasing. In the case of joining aluminum, joining using resistance joining is the most frequently used joining method. However, in this method, since aluminum has a relatively high electrical conductivity, heat generation due to resistance is small, and since aluminum has a high thermal conductivity, welding heat is likely to be dissipated, making welding difficult. Furthermore, resistance welding is instantaneously melted by applying a large current to a metal material and then rapidly cooled, so that welding defects such as cracks are likely to occur, deformation due to thermal strain is large, and welding is also performed. There are a number of problems such as deterioration of the mechanical properties of the parts.

  As a method for solving these problems and joining aluminum alloys, there is friction point joining. In this friction point joining, in general, frictional heat is generated by contacting a metal material while rotating a rotor having a pin protrusion on a shoulder portion having a flat bottom surface, and the region including the joint is plastically flowed by stirring with a pin. Bonding is performed by generating In other words, this joining method is a kind of solid-phase joining that does not involve melting of the metal material, and there is no material deterioration due to melting and solidification as seen in ordinary resistance welding, and there is very little deformation and high-speed joining is possible. There are many advantages such as clean environment. Furthermore, while other welding, such as laser welding or electron beam welding, requires expensive equipment, friction spot joining is simple in equipment and has excellent cost performance and energy efficiency.

  However, in friction point bonding, after the metal material is softened and agitated with frictional heat, when the rotor is retracted from the metal material, the pin also retracts at the same time, so a pin-shaped hole remains in the metal material. . When such a hole is formed, stress concentrates on the hole, so that the bonding strength is reduced and the hole is easily damaged. In addition, there is a problem that the appearance is deteriorated and the commercial value is lowered.

  Therefore, a method of suppressing the generation of holes by filling the holes with the base material by repressurizing the region including the holes after first retracting only the pins into the rotor after the joining is completed. However, in this method, the pins are retracted into the rotor after the joining is completed, and then re-pressurization is performed, so that the time required for joining becomes longer, and the base material is cooled while the pins are retracted. In order to cure, the hole may not be sufficiently filled even if re-pressurization is performed thereafter.

  In view of such a problem, a joining method using a friction spot joining apparatus as disclosed in Patent Document 1 is known as a friction spot joining capable of filling a hole and joining a metal material in a short time. ing. In this friction point joining apparatus, the pin is retracted in a state where the metal material is being pressurized at the tip of the rotor after the joining is completed, so that the softened base material around the hole generated by retracting the pin does not harden. It will be possible to flow in and fill the hole reliably.

JP 2002-192358 A

  However, in the above method, since the pin passes through the first metal member on the upper side among the stacked metal members and reaches the second metal member on the lower side, the hole is not filled well and the first is not filled well. When the second metal member is exposed to the outside and the second metal member is a dissimilar metal having a different ionization tendency from that of the first metal member, such as steel, an electric corrosion problem occurs and the metal member is greatly damaged. appear.

  Therefore, the present invention relates to a method and apparatus for performing frictional point bonding by pressing a rotor while rotating a rotor by overlapping a first metal member and a second metal member made of different materials. It is an object of the present invention to provide a method and an apparatus for performing friction spot joining that reliably avoids exposure to the outside, and thus does not cause the problem of electrical corrosion even when joining different metals.

  In order to solve the above-mentioned problems, the present invention is configured as follows.

First, the invention according to claim 1 of the present application is a method of performing friction point joining by superimposing a first metal member and a second metal member made of different materials and pressing while rotating the rotary pressurizing means. In addition, as the rotary pressurizing means, a tip is used as a shoulder portion, and a pin member that can be relatively advanced and retracted is inserted into a hole passing through the center. The receiving member disposed coaxially and oppositely is used to support the overlapped metal member with the receiving member from the second metal member side, and the pin member is protruded from the shoulder portion and rotated. push while the pressing means is rotated from the side of the first metal member, before the pin member has reached the second metal member penetrates the first metal member in a state where the shoulder portion is entered into the first metal member, the pin a member End is retracted to lie within the shoulder portion, then, to soften the first metal member by using the frictional heat is continued rotational movement and pressing operation of the rotary pressure means generated, resulting plastic flow The overlap portion between the two metal members is solid-phase bonded.

In the invention according to claim 2 of the present application, the rotary pressurizing means is rotated by superimposing a plurality of adjacent first metal members and one second metal member made of a different material from the first metal member. In this method, friction point joining is performed by pressing while the tip is composed of a shoulder portion having a large diameter and a shoulder portion having a small diameter protruding from the shoulder portion, and the center as a center. A metal member that is overlapped with the second metal member is inserted into the second hole by using a receiving member that is coaxially disposed opposite to the rotary pressurizing unit. While supporting by the receiving means from the metal member side, and pushing the rotating pressure means from the side of the plurality of adjacent first metal members in a state where the pin member protrudes from the small diameter shoulder portion , Small above In a state where the shoulder portion of entered a first metallic member adjacent a second metallic member, before the pin member has reached the second metal member penetrates the same first metal member, the tip of the pin member of the smaller diameter The first metal member is softened by using the frictional heat generated by continuing the rotation operation and the pressurizing operation of the rotary pressurizing unit to be moved backward so as to be positioned in the shoulder portion, thereby generating a plastic flow. The overlapping portions of the first metal member and the second metal member are solid-phase bonded, and the overlapping portions of a plurality of adjacent first metal members are bonded.

  Next, in the invention according to claim 3 of the present application, in the invention according to claim 1 or 2, the first metal member is an aluminum alloy plate, and the second metal member is provided with a metal plating layer. In addition to being a steel plate, the metal plating material is softened using frictional heat generated by the rotational operation and the pressurizing operation of the rotary pressurizing unit at the time of joining, and after being pushed out from the joining site by the pressurizing operation, the first The metal member and the second metal member are solid-phase bonded.

Further, the invention according to claim 4 of the present application is an apparatus that performs friction point joining by superimposing the first metal member and the second metal member made of different materials and pressing the rotary pressurizing means while rotating. The tip is a shoulder portion, and a rotary pressurizing means in which a pin member that can be relatively advanced and retracted in a hole passing through the center is inserted , and the rotary pressurizing means is coaxially arranged oppositely. A receiving means, a pin moving means for moving the pin member forward and backward relative to the rotary pressurizing means, and an overlapping metal member supported by the receiving means from the second metal member side, and the pin the members in a state of projecting from the shoulder indentation while rotating the rotary pressing means from the side of the first metal member, said pin member in a state where the shoulder portion is entered into the first metal member is a first metal member Thrust Before only reaching the second metal member, the tip of the pin member is retracted to lie within the shoulder portion, then, the frictional heat generated by continuing the rotation operation and pressing operation of the rotating pressing means And a drive control means for controlling the rotary pressurizing means and the pin moving means so as to soften the first metal member and cause a plastic flow to solid-phase the overlapping portion between the two metal members. It is characterized by that.

In the invention according to claim 5 of the present application, the rotary pressurizing means is rotated by overlapping a plurality of adjacent first metal members and one second metal member made of a different material from the first metal member. It is a device that performs friction point joining by pressing while having a tip composed of a large-diameter shoulder portion and a small-diameter shoulder portion protruding from the shoulder portion, and relatively to a hole portion penetrating the center. Rotating and pressing means in which a pin member that can be advanced and retracted is inserted , receiving means that is coaxially disposed opposite the rotating and pressing means, and the pin member is moved forward and backward relative to the rotating and pressing means . A plurality of adjacent pin members are supported by the receiving means from the side of the second metal member, and the rotating and pressing means are adjacent to each other with the pin member protruding from the small diameter shoulder portion. The first metal part of Push while rotating from the side of, in a state where the shoulder portion of the smaller diameter has entered the first metal member adjacent to the second metal member, before the pin member has reached the second metal member penetrates the same first metal member In addition, the first metal member is moved using the frictional heat generated by retracting the pin member so that the tip is located in the shoulder portion having the small diameter , and then continuing the rotation operation and the pressure operation of the rotary pressurizing means. Rotating and pressurizing so that the overlap part of the 1st metal member and the 2nd metal member is solid-phase-bonded by softening and generating plastic flow, and the overlap part of a plurality of adjacent 1st metal members is joined And a drive control means for controlling the pin moving means.

  Next, in the invention described in claim 6 of the present application, in the invention described in claim 4, the shoulder portion at the tip of the rotary pressurizing means is formed in a concave portion inclined conically toward the center. It is characterized by.

In the invention according to claim 7 of the present application, in the invention according to claim 5, the small-diameter shoulder portion at the tip of the rotary pressurizing means is formed in a concave portion inclined conically toward the center. It is characterized by that.

By configuring as described above, first, according to the first aspect of the present invention, before the pin member protruding from the shoulder portion of the rotary pressurizing means penetrates the first metal member and reaches the second metal member. by retracting the pin member within the shoulder portion, the pin member can be avoided a situation in which the electric corrosion problems caused by the second metal member reaches the second metal member is exposed to the outside, a shoulder pin member possible to obtain a stable bonding surface by pressurizing operation by the shoulder portion after retracting the portion become.

According to the second aspect of the present invention, a plurality of adjacent first metals are formed by using the rotary pressurizing means having a large-diameter shoulder portion and a small-diameter shoulder portion protruding from the shoulder portion. Even when three or more metal materials obtained by superimposing a member and one second metal member are joined , the pin member is retracted into a small-diameter shoulder before the pin member reaches the second metal member. The pin member reaches the second metal member and the second metal member is exposed to the outside, so that a situation of an electric corrosion problem is avoided, and a stable joint surface is obtained by the pressing operation by the small-diameter shoulder portion. Can be obtained.

  Next, according to the invention described in claim 3, an aluminum alloy plate is used for the first metal member, and a steel plate provided with a zinc plating layer for preventing corrosion, for example, as the metal plating layer on the second metal member is used. When performing friction point bonding, zinc has a melting point lower than that of aluminum, and is softened by frictional heat generated by the rotating operation of the rotor, resulting in plastic flow, and the galvanized layer that has been softened by the pressing operation is outside the periphery of the shoulder portion. Therefore, it is possible to reliably perform solid-phase bonding between the aluminum alloy plate and the steel plate without interposing a galvanized layer therebetween.

According to the invention described in claim 4, similarly to the invention described in claim 1, the first metal member is penetrated and the pin member is retracted into the shoulder portion before the pin member reaches the second metal member. be to bonding surface of the pin member and the second metal member reaches the second metal member with a situation where the electric corrosion problems caused by being exposed to the outside is avoided, and stable in the pressurizing operation by the shoulder portion Can be obtained.

According to the invention described in claim 5, as in the invention described in claim 2, the rotary pressurizing composed of a shoulder portion having a large diameter and a small diameter shoulder portion protruding from the shoulder portion. In the case of joining three or more metal materials in which a plurality of adjacent first metal members and one second metal member are overlapped using the means , the pin member penetrates the first metal member and the second member By retreating the pin member into the small-diameter shoulder before reaching the metal member, the situation where the pin member reaches the second metal member and the second metal member is exposed to the outside is avoided. In addition, it is possible to obtain a stable joint surface by the pressurizing operation by the small diameter shoulder portion.

  Next, according to the invention described in claim 6, the shoulder portion is formed in the concave portion inclined in a conical shape toward the center, whereby the first metal member softened inside the rotor is provided. A space for plastic flow is provided, and the metal member near the shoulder is not pushed out, but is confined inside and used as a pressure medium, so that pressure is transmitted to the second metal member at the time of joining, and the pressurizing operation by the rotor is ensured. Can be done.

  According to the seventh aspect of the present invention, similarly to the sixth aspect of the present invention, the first shoulder portion is formed in the concave portion inclined conically toward the center, so that the rotor A space for plastically flowing the softened first metal member inside is provided, and the metal member in the vicinity of the first shoulder portion is confined inside without being pushed outward, and is used as a pressure medium. The pressure can be transmitted to the rotor and the pressurizing operation by the rotor can be reliably performed.

  Hereinafter, embodiments of the present invention will be described with reference to the drawings.

  First, a specific configuration of a bonding apparatus that performs the method according to the present invention will be described.

  FIG. 1 shows a system configuration of a joining apparatus according to the present embodiment. This joining apparatus is used for joining a workpiece W as a member to be joined. It is used for joining an aluminum plate (one metal member) W1 such as an aluminum alloy used in the above and a steel plate (other metal member) W2 provided with a galvanized layer Z1 in an overlapped state.

  In this embodiment, the friction point welding apparatus according to the present invention is applied to the joining gun 1 shown in FIG. 1, and the joining gun 1 is attached to the tip of the robot arm 100.

  The robot arm 100 has a function of positioning the joining gun 1 at a joining position between the aluminum alloy plate W1 and the steel plate W2.

  As shown in FIG. 1, the joining gun 1 includes a rotor 2 and a receiver 3 as joining tools for joining the aluminum alloy plate W1 and the steel plate W2.

  The rotor 2 is made of tool steel, and sufficient strength is ensured even at a temperature at which the bonding material softens. The rotor 2 is disposed on the joint center line X, and is rotated about the joint center line X by the rotary shaft motor M1. That is, the rotor 2 is fixed to the mounting flange 5 of the cylindrical turning shaft 4.

  A first pulley 8 is attached to the upper end of a cylindrical drive shaft 7 rotatably supported on the main body of the joining gun 1 via a bearing 6, and the lower end is inserted into the hole of the revolving shaft 4. The swivel shaft 4 is splined by a spline.

  On the other hand, a second pulley 9 is attached to the rotating shaft of the rotating shaft motor M1, and the first pulley 8 is driven via a toothed belt 10 driven by the second pulley 9, and the driving shaft 7 and the turning shaft are driven. The rotor 2 rotates via 4.

  Further, the rotor 2 is configured to be moved up and down along the joint center line X for pressurization by a pressurizing shaft motor M2 as pressurizing means. That is, a cylindrical elevating cylinder 13 is provided on an elevating member 12 that is screwed and raised to a screw shaft 11 that is rotatably arranged on the main body of the joining gun 1, and a bush 14 is provided on the lower end side of the elevating cylinder 13. And is supported by the main body of the joining gun 1 so as to be movable up and down.

  Inside the elevating cylinder 13, the pivot shaft 4 is rotatably supported via a bearing 15.

  On the other hand, a third pulley 16 is attached to the rotary shaft of the pressure shaft motor M2, and a fourth pulley 18 attached to the screw shaft 11 is driven via a toothed belt 17 driven by the third pulley 16. Then, the elevating member 12 and the elevating cylinder 13 are moved up and down by the rotation of the screw shaft 11, the turning shaft 4 is moved up and down through the bearing 15, and the rotor 2 is moved up and down on the joining center line X.

  The movable pin 19 includes a joint 20 at the upper end and a pin member 21 at the lower end. The movable pin 19 is inserted into a hole passing through the center of the rotor 2 and is splined to the rotor 2. The upper end of the movable pin 19 is connected to the operation shaft 22 via the joint 20, and the operation shaft 22 is inserted into a hole inside the drive shaft 7 and is splined to the drive shaft 7. .

  For this reason, the rotor 2 and the movable pin 19 rotate integrally with the rotation of the drive shaft 7.

  The upper end of the operation shaft 22 is connected to a bar member 24 through a bearing 23. Further, the rack 25 provided on the rod member 24 is engaged with the pinion 26, and the pin 27 is operated via the pinion 26 and the rack 25 by operating the pin shift linear motor M3 and rotating the gear 27. 19 is moved up and down.

  An induction motor or a servo motor can be used as the rotary shaft motor M1, and a servo motor can be used as the pressure shaft motor M2.

  The receiver 3 is disposed opposite to the rotor 2, and this position is maintained by using the substantially L-shaped arm 40 and attaching the receiver 3 to the tip thereof. The rotor 2 and the receiving tool 3 are detachably attached to the bonding gun 1.

  The controller 50 outputs control signals to the rotary shaft motor M1, the pressure shaft motor M2, and the pin shift linear motor M3, and when the rotor 2 moves up and down along the joint center line X, the rotor 2 The robot arm 100 receives an output signal from the controller 28, an encoder 28 for grasping the position, a touch sensor 29 that detects the moment when the lower end of the rotor 2, that is, the pin member 21 first contacts the aluminum alloy plate W 1, and the controller 50. A robot arm actuator 30 for controlling the driving of the rotor 2 is provided in the joining device, and a control system for each operation of the rotating operation and pressurizing operation of the rotor 2 and the retreating operation of the movable pin 19 into the rotor is provided. Forming.

  Next, the rotor 2 and the receiver 3 will be described with reference to FIG. The rotor 2 integrally includes a main body 2a and a movable pin 19 whose main purpose is centering (positioning function, position shift prevention function). The main body 2a is formed in a substantially cylindrical shape, and the arrangement thereof is set so that its axis coincides with the joint centerline X. The shoulder portion 2b at the tip of the rotor 2 forms a conical recess inclined toward the movable pin 19 side, and the recess becomes deeper as it goes inward in the radial direction of the rotor 2. Yes. The movable pin 19 is disposed so that the axis of the movable pin 19 coincides with the axis of the rotor 2 (joint center line X), and the pin member 21 has a smaller diameter than the rotor 2 so that the pin member 21 of the rotor 2 It protrudes from the tip surface, and the tip surface is formed as a flat surface. In this case, the shape of the distal end surface is more preferably a curved surface shape having a curvature radius of about 40 mm, whereby a centripetal force is generated during rotation of the rotor 2 and the push-in becomes smooth. Of course, in addition to this, another aspect of the rotor 2 is that it is generally cylindrical and has a flat tip surface, and is generally cylindrical, and the periphery of the tip surface is slightly rounded. In the embodiment according to the above-described embodiment, the rotor 2 having a shape in which the tip surface of the rotor 2 is slightly inflated may be used.

  In order to embody the present invention, the shape of the recess (concave portion) formed in the shoulder portion 2b is more preferably a shape that becomes deeper inward in the radial direction as described above. That is, in the present invention, as will be described later, the rotor 2 simultaneously plays the role of softening the antioxidant metal film formed for the purpose of the present invention and pushing it out in the outer circumferential direction when pressurized. However, a recess (concave portion) having the above-described shape is more preferable for achieving this function. In other words, this shape can suppress as much as possible that the metal material of the metal member (for example, an aluminum member) that softens and plastically flows due to frictional heat and escapes to the outer periphery of the rotor. This is because the pressure force of the child can be effectively applied to the metal film for preventing oxidation and pushed out to the outer periphery.

  The receiver 3 is formed in a substantially cylindrical shape having the same diameter as that of the rotor 2, and its tip end surface is formed as a flat surface.

Next, a method for joining the workpieces W will be described in detail using the joining device.
[First example of joining operation]
First, as a first joining operation example, a case where friction point joining is performed between an aluminum alloy plate and a steel plate provided with an anti-oxidation galvanized layer will be described.

  As shown in FIG. 2, before joining the aluminum alloy plate W1 and the steel plate W2, in a state where the pin member 21 is projected from the tip portion, the rotor 2 is rotated by the rotary shaft motor M1 while being in the joining center line X direction. A pressurizing shaft motor M2 and a pin-shifting linear motor M3 are approaching the aluminum alloy plate W1 from above, and the support 3 is not rotated and is coated with a galvanized layer Z1 from below in the coaxial direction. It is approaching the steel plate W2.

  As shown in FIG. 3, when the pin member 21 and the support 3 are simultaneously in contact with the aluminum alloy plate W1 and the steel plate W2, respectively, the aluminum alloy plate W1 and the aluminum alloy plate W1 are caused by the frictional heat generated by the rotation of the pin member 21. The galvanized layer Z1 applied to the steel plate W2 begins to soften, and a softened region S is generated. Using this moment as a point for starting the joining of the aluminum alloy plate W1 and the steel plate W2, there are two cases: a case where a pin member 21 described later is retracted into the rotor 2 by time setting, and a case where the pin member 21 is retracted by position setting. Use as a standard for setting.

  Next, as shown in FIG. 4, the pin member 21 is caused to enter the aluminum alloy plate W1 along the joint center line X while the rotor 2 is continuously rotated, and the axis of the steel plate W2 by the support 3 When the support from the lower side is performed, the shoulder portion 2b comes into contact with the aluminum alloy plate W1. At this time, not only the frictional heat generated by the rotation operation of the pin member 21, but also the frictional heat generated by the contact of the shoulder portion 2b having a larger contact area with the aluminum alloy plate W1 than the pin member 21, is applied. The softened region S of the galvanized layer Z1 applied to the plate W1 and the steel plate W2 expands, the aluminum alloy plate W1 is sheared by the rotational movement of the shoulder portion 2b, and the aluminum member around the shoulder portion 2b rises and flashes B Occurs.

  In this operation example, the pin member 21 is retracted into the rotor 2 when the shoulder portion 2b reaches a position where it contacts the aluminum alloy plate W1.

  As described above, there are two methods for setting the timing for retracting the pin member 21 into the rotor 2, that is, the time setting method and the position setting method.

  First, a method for determining the timing for retracting the pin member 21 into the rotor 2 by setting the time will be described with reference to the control system diagram of FIG.

When the pin member 21 and the receiving member 3 are simultaneously in contact with the aluminum alloy plate W1 and the steel plate W2, respectively, a detection signal from the touch sensor 29 is input to the controller 50, and the time since the detection signal is input. Time is measured by a timer 31 built in the controller 50. Then, the controller 50 outputs a control signal for the rotary shaft motor M1. The rotational speed of the rotor 2 driven by the rotary shaft motor M1 is fed back to the controller 50 again, and parameter-converted into an elapsed time from the time when the timer 31 starts timing. Then, when the time measured by the timer 31 reaches the set time, the robot is controlled to move the pin member 21 back into the rotor 2 by rotational driving of the pin shift linear motor M3. This set time is obtained experimentally in advance and input to the robot.

  Next, a method for determining the timing for retracting the pin member 21 into the rotor 2 by setting the position will be described with reference to the control system diagram of FIG.

The position of the pin member 21 when the pin member 21 and the receiver 3 are simultaneously in contact with the aluminum alloy plate W1 and the steel plate W2 is determined as the origin, and at this time, an input signal from the encoder 28 is input to the control unit 50. Then, a control signal to the pressure shaft motor M2 is output. The amount of rotational displacement of the pressure shaft motor M2 from the time when the pin member 21 is at the origin to the present is converted into a parameter by the distance that the pin member 21 moves from the origin along the joining center line X, and then the encoder. 28 is fed back. By repeating this operation, the position on the joint center line X of the pin member 21 until the shoulder portion 2b contacts the aluminum alloy plate W1 is constantly grasped.

  When the position of the pin member 21 is reached, that is, the position of the pin member 21 when the shoulder portion 2b contacts the aluminum alloy plate W1, the robot is controlled to retract the pin member 21 into the rotor 2. . The set position is experimentally obtained in advance, and parameters are set and input to the robot.

  As described above, the pin member 21 reaches the steel plate W2 through the aluminum alloy plate W1 and retracted before the pin member 21 reaches the steel plate W2, so that the steel plate W2 is exposed to the outside. As a result, it is possible to avoid a situation in which the problem of electric corrosion occurs, and to obtain a stable joint surface by the subsequent pressurizing operation by the shoulder portion 2b.

  Further, since the shoulder portion 2b is formed in a concave portion inclined conically toward the center of the rotor 2, a space for plastically flowing the softened aluminum alloy plate W1 is provided inside the rotor 2. Since the aluminum alloy plate W1 in the vicinity of the shoulder portion 2b is confined inside without being pushed out to be a pressure medium, the pressure is transmitted to the steel plate W2 at the time of joining, and the pressurizing operation by the rotor 2 can be performed reliably. It becomes.

  Next, as shown in FIG. 5, after the pin member 21 is completely retracted into the rotor 2, if the rotor 2 is rotated and further entered into the aluminum alloy plate W1, it is applied to the steel plate W2. Since the galvanized layer Z1 has a melting point lower than that of aluminum, it is softened by frictional heat generated by the rotating operation of the rotor 2. The galvanized layer Z1 undergoes plastic flow, and most of the film Z2 softened by the pressurizing operation of the rotor 2 is pushed out of the shoulder portion 2b and part thereof is taken into the aluminum alloy material. The aluminum alloy plate W1 and the steel plate W2 can be solid-phase bonded without sandwiching the plating layer Z1.

  Next, as shown in FIG. 6, in a state in which the rotor 2 is most deeply submerged in the aluminum alloy plate W <b> 1, the galvanized layer Z <b> 1 applied to the steel plate W <b> 2 is applied to the rotor 2 by the pressurizing operation of the rotor 2. Therefore, the solid-phase joining of the aluminum alloy plate W1 and the steel plate W2 is reliably performed at this time. At this time, an intermetallic compound Y of aluminum and zinc is generated in the film Z2 of the softened galvanized layer Z1 pushed out around the shoulder portion 2b by the rotating operation of the rotor 2.

  Then, as shown in FIG. 7, after the joining is completed, the rotor 2 and the receiving tool 3 are retracted from the aluminum alloy plate W1 and the steel plate W2 along the joining center line X, respectively. At this time, when the rotating operation of the rotor 2 is stopped and then retracted from the aluminum alloy plate W1, aluminum that has been cooled and hardened adheres to the rotor 2, and the work W that has been joined is retracted from the rotor 2. Since there is a possibility that they may be lifted together, the rotor 2 is retracted from the workpiece W while rotating.

In addition, since the entire joining surface of the workpiece W is solid-phase joined, there are many joining surfaces, and iron and aluminum are integrated at the atomic level, so that the joining strength is increased compared to resistance welding. Yes.
[Second example of joining operation]
Next, as a second joining operation example, a case where friction point joining is performed between two adjacent aluminum alloy plates and one steel plate provided with a corrosion-preventing galvanized layer will be described.

  As shown in FIG. 8, the rotor 2 is in a state where the pin member 21 protrudes from the tip of the rotor 2 before joining the first aluminum alloy plate W1, the second aluminum alloy plate W3, and the steel plate W2. While rotating, it approaches the first aluminum alloy plate W1 from the upper side in the joining axis direction, and the receiver 3 approaches the steel plate W2 on which the galvanized layer Z1 is applied from the lower side in the coaxial direction without rotating. Yes.

  Then, as shown in FIG. 9, when the pin member 21 and the receiving member 3 are simultaneously in contact with the first aluminum alloy plate W1 and the steel plate W2, respectively, the first aluminum is generated by the frictional heat generated by the rotation of the pin member 21. The alloy plate W1, the second aluminum alloy plate W3, and the galvanized layer Z1 applied to the steel plate W2 begin to soften, and a softened region S is generated. Using this moment as a starting point for joining the first aluminum alloy plate W1, the second aluminum alloy plate W3, and the steel plate W2, the pin member 21 is retracted into the rotor 2 by setting the time as in the first embodiment. And a reference for setting in two cases, that is, the case of reversing by position setting.

  Next, as shown in FIG. 10, the pin member 21 is made to enter the first aluminum alloy plate W1 along the joint center line X while the rotor 2 is continuously rotated, and the steel plate W2 by the support 3 is used. When the support from the lower side in the axial direction is performed, the shoulder portion 2b comes into contact with the first aluminum alloy plate W1. At this time, not only the frictional heat generated by the rotation operation of the pin member 21, but also the frictional heat generated by the contact of the shoulder portion 2b having a larger contact area with the first aluminum alloy plate W1 than the pin member 21, is added. The softened region S of the galvanized layer Z1 applied to the first aluminum alloy plate W1, the second aluminum alloy plate W3, and the steel plate W2 is enlarged, and the first aluminum alloy plate W1 is sheared by the rotational motion of the shoulder portion 2b, The aluminum member around the shoulder portion 2b rises and a burr B is generated.

  In this joining operation example, when the shoulder portion 2b reaches a position where it contacts the second aluminum alloy plate W3, the pin member 21 is retracted into the rotor 2.

  As described above, there are two methods for setting the timing for retracting the pin member 21 into the rotor 2, that is, the time setting method and the position setting method. However, since the setting method is the same as that in the first operation example, description thereof is omitted.

  By penetrating the first aluminum alloy plate W1 and retracting the pin member 21 before the pin member 21 reaches the steel plate W2, the pin member 21 reaches the steel plate W2 and the steel plate W2 is exposed to the outside. It is possible to avoid a situation in which an electric corrosion problem occurs and to obtain a stable joint surface by a subsequent pressurizing operation by the shoulder portion 2b.

  Further, the shoulder portion 2b is formed in a concave portion inclined in a conical shape toward the center of the rotor 2, so that the first aluminum alloy plate W1 and the second aluminum alloy softened inside the rotor 2 are formed. A space for plastically flowing the plate W3 is provided, and the first aluminum alloy plate W1 and the second aluminum alloy plate W3 in the vicinity of the shoulder portion 2b are confined in the inside without being pushed outward, so that the pressure medium is obtained. The pressure can be transmitted and the pressurizing operation by the rotor 2 can be performed reliably.

  Next, as shown in FIG. 11, after the pin member 21 is completely retracted into the rotor 2, the steel plate W2 is moved into the second aluminum alloy plate W3 while rotating the rotor 2. Since the galvanized layer Z1 applied to is lower in melting point than aluminum, it is softened by frictional heat generated by the rotating operation of the rotor 2. The galvanized layer Z1 undergoes plastic flow, and most of the film Z2 softened by the pressurizing operation of the rotor 2 is pushed out of the shoulder portion 2b and part thereof is taken into the aluminum alloy material. The first aluminum alloy plate W1 and the steel plate W2 can be solid-phase bonded without sandwiching the plating layer Z1.

  In the adjacent first aluminum alloy plate W1 and second aluminum alloy plate W3, the vicinity of the joint is sheared and raised by the rotational operation of the rotor 2, and burrs are generated. They are joined by biting each other between the boards.

  Next, as shown in FIG. 12, in a state where the rotor 2 is submerged most deeply into the first aluminum alloy plate W1 and the second aluminum alloy plate W3, it is applied to the steel plate W2 by the pressurizing operation of the rotor 2. Since the galvanized layer Z1 is extruded to the outside of the periphery of the rotor 2, at this time, the solid-phase bonding of the first aluminum alloy plate W1 and the steel plate W2 and the first aluminum alloy plate W1 and the second aluminum alloy plate are performed. W3 is reliably joined. At this time, an intermetallic compound Y of aluminum and zinc is generated in the film Z2 of the softened galvanized layer Z1 pushed out around the shoulder portion 2b by the rotating operation of the rotor 2.

  Then, as shown in FIG. 13, after the joining is completed, the rotor 2 and the receiver 3 are retracted from the aluminum alloy plate W <b> 1 and the steel plate W <b> 2 along the joining center line X, respectively. At this time, if the rotating operation of the rotor 2 is stopped and then withdrawn from the aluminum alloy plate W1, the cooled and hardened aluminum adheres to the rotor 2, and the rotor 2 is withdrawn from both metal plates that have been joined. Since there is a possibility that the rotors 1 may be lifted together at the same time, the rotor 1 is retracted from the workpiece W while rotating.

  In addition, since the entire joining surface of the workpiece W is solid-phase joined, there are many joining surfaces, and iron and aluminum are integrated at the atomic level, so that the joining strength is increased compared to resistance welding. Yes. In addition, the joining surfaces of the first aluminum alloy plate W1 and the second aluminum alloy plate W3 also have portions that are sheared and raised by the rotating operation of the rotor 2 bite each other. Absent.

  Further, when the shoulder portion 2b is in contact with the second aluminum alloy plate W3, the pin member 21 is retracted to the inside of the rotor 2, so that the steel plate W2 is exposed to the outside after the joining, so that the steel plate W2 is exposed to the steel plate W2. Situations where electrocorrosion problems occur are reliably avoided.

  As described above, according to the present invention, the present invention provides a method for performing friction point joining by pressing the rotor while rotating the rotor by overlapping the first metal member and the second metal member made of different materials, and In the apparatus, it is possible to reliably prevent the second metal member from being exposed to the outside, and to perform friction point joining that does not cause the problem of electric corrosion even when joining different metals. Widely suitable for the technical field of the material joining method, in particular, the friction point joining method in which the metal material is softened by using frictional heat generated by the rotor, agitated, and the plastic flow is caused to join, and the apparatus thereof. is there.

It is a system diagram of a joining device concerning an embodiment of the present invention. It is an operation | movement side view before joining of the 1st joining operation example. It is an operation | movement side view at the time of the joining start of the 1st joining operation example. It is an operation | movement side view during joining of the 1st joining operation example. It is an operation | movement side view at the moment of retracting | retracting the pin of the 1st example of a joining operation | movement inside a rotor. It is an operation | movement side view at the moment when the rotor of the 1st joining operation example sank most deeply. It is an operation | movement side view after the completion | finish of joining of the 1st joining operation example. It is an operation | movement side view before joining of the 2nd joining operation example. It is an operation | movement side view at the time of the joining start of the 2nd joining operation example. It is an operation | movement side view during joining of the 2nd joining operation example. It is an operation | movement side view at the moment of retracting the pin of the 2nd joining operation example inside a rotor. It is an operation | movement side view at the moment when the rotor of the 2nd joining operation example sank most deeply. It is an operation | movement side view after the completion | finish of joining of the 2nd joining operation example.

Explanation of symbols

2 Rotor (rotating pressure means)
2a Rotor body 2b Shoulder part 3 Receiving tool (receiving means)
19 movable pin 21 pin member W1 first aluminum alloy plate W2 steel plate W3 second aluminum alloy plate Z1 galvanized layer M1 rotary shaft motor M2 pressure shaft motor M3 linear motor for pin shift (pin moving means)
50 Control unit (drive control means)

Claims (7)

It is a method for performing friction point joining by overlapping the first metal member and the second metal member made of different materials and pressing while rotating the rotary pressurizing means,
As the rotation pressurizing means, a tip is used as a shoulder portion, and a pin member that can be relatively advanced and retracted in a hole portion that penetrates the center is used, and
Using the receiving means disposed coaxially with the rotary pressurizing means, the superposed metal member is supported by the receiving means from the second metal member side, and
In a state where the pin member protrudes from the shoulder portion , the rotary pressurizing means is pushed in while rotating from the first metal member side,
Before the shoulder portion is the pin member in a state that entered the first metal member reaches the second metal member penetrates the first metal member, the tip of the pin member is retracted to lie within the shoulder portion,
Thereafter, the first metal member is softened by using the frictional heat generated by continuing the rotation operation and the pressurization operation of the rotary pressurizing means, and a plastic flow is generated so that the overlapping portion between the two metal members is solid-phased. Friction point joining method characterized by joining. In this method, a plurality of adjacent first metal members and one second metal member made of a different material are overlapped with each other and pressed while rotating the rotary pressurizing means to perform friction point joining. And
As the rotary pressurizing means, a pin member that is composed of a shoulder portion having a large diameter at the tip and a small shoulder portion protruding from the shoulder portion and that can be relatively advanced and retracted into a hole portion that penetrates the center is inserted. I used those, and,
Using the receiving means disposed coaxially with the rotary pressurizing means, the superimposed metal member is supported by the receiving means from the second metal member side, and
The pin member is pushed in while rotating from the side of the plurality of adjacent first metal members in a state where the pin member is protruded from the small-diameter shoulder portion ,
With the small-diameter shoulder portion protruding into the first metal member adjacent to the second metal member, before the pin member penetrates the first metal member and reaches the second metal member, the tip of the pin member is Retract so that it is located in the small diameter shoulder ,
After that, the first metal member is softened by using the frictional heat generated by continuing the rotation operation and the pressurization operation of the rotary pressurizing means, and a plastic flow is caused to occur between the first metal member and the second metal member. A friction point joining method characterized by solid-phase joining the overlapping portions and joining the overlapping portions of a plurality of adjacent first metal members.   The first metal member is an aluminum alloy plate, the second metal member is a steel plate provided with a metal plating layer, and at the time of joining, using the frictional heat generated by the rotating operation and the pressing operation of the rotating pressurizing means. The first metal member and the second metal member are solid-phase bonded after the metal plating material is softened and extruded from the bonding portion by a pressurizing operation. Friction spot welding method. A device that performs friction point joining by superimposing a first metal member and a second metal member made of different materials and pressing while rotating a rotary pressurizing means,
A rotary pressurizing means in which a tip member is a shoulder portion and a pin member that can be relatively advanced and retracted in a hole portion that penetrates the center ;
Receiving means disposed coaxially with the rotary pressurizing means;
A pin moving means for moving the pin member forward and backward relative to the rotary pressurizing means;
While the superimposed metal member is supported by the receiving means from the second metal member side, the rotary pressurizing means is rotated from the first metal member side with the pin member protruding from the shoulder portion. pushing, before the shoulder portion is the pin member in a state that entered the first metal member reaches the second metal member penetrates the first metal member, the tip of the pin member is retracted to lie within the shoulder portion Thereafter, the first metal member is softened by using the frictional heat generated by continuing the rotation operation and the pressurization operation of the rotary pressurizing means, and a plastic flow is generated to fix the overlapping portion between the two metal members. A friction point welding apparatus comprising: a drive controller for controlling the rotary pressurizing unit and the pin moving unit so as to perform phase welding. This is a device that performs friction point joining by overlapping a plurality of adjacent first metal members and one second metal member made of a different material with the first metal member and pressing while rotating the rotary pressurizing means. And
A rotary pressurizing means in which a distal end is constituted by a shoulder portion having a large diameter and a small diameter shoulder portion protruding from the shoulder portion, and a pin member which is relatively movable in a hole passing through the center is inserted ; ,
Receiving means disposed coaxially with the rotary pressurizing means;
A pin moving means for moving the pin member forward and backward relative to the rotary pressurizing means;
The overlapped metal member is supported by the receiving means from the side of the second metal member, and the rotation pressing means is adjacent to the first metal member in a state where the pin member protrudes from the small-diameter shoulder portion. Before the pin member penetrates the first metal member and reaches the second metal member in a state where the small diameter shoulder portion has entered the first metal member adjacent to the second metal member. In addition,
The pin member is retracted so that the tip is located in the shoulder portion having the small diameter , and thereafter, the first metal member is softened by using frictional heat generated by continuing the rotation operation and the pressurization operation of the rotary pressurizing means. And rotating and pressing means so as to join the overlapping portions of the plurality of first metal members adjacent to each other while causing the plastic flow to cause solid-phase bonding of the overlapping portions of the first metal member and the second metal member. A friction point welding apparatus comprising drive control means for controlling the pin moving means.   The friction point joining device according to claim 4, wherein a shoulder portion at a tip of the rotary pressurizing means is formed in a concave portion inclined in a conical shape toward the center. 6. The friction point joining device according to claim 5, wherein a small-diameter shoulder portion at the tip of the rotary pressurizing means is formed in a concave portion inclined conically toward the center.

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