JP2013123745A - Friction stir welding tool and friction stir welding method - Google Patents

Abstract

PROBLEM TO BE SOLVED: To prevent bonding failure even if a gap is present in the joint of a workpiece with large plate thickness.SOLUTION: A probe 2 longer than a workpiece 10 in plate thickness and a shoulder 3 at the lower edge side thereof can be rotation-driven. A stationary type shoulder 5 to be in contact with the upper face of the workpiece 10 includes: an opening part 6 to be inserted with the probe 2; and a guide groove 7 communicated with the opening part 6 along the lower face. A filler feeding means 8, for feeding a rod-like filler 9 to be energized through the guide groove 7 toward the probe 2 arranged at the opening part 6 of the stationary type shoulder 5, is included to form a friction stir welding tool 1. In the workpiece 10, in a state where heat input is increased by friction with the shoulder 3, a plastic flow region is formed at the whole of the plate thickness by the probe 2. In the case where a gap is present at the joint, the filler 9 softened by friction with the probe 2 is fed to the plastic flow region around the probe 2 directly below the filler 9, and a shortage of the stock of the workpiece 10 by the gap is filled.

Description

  The present invention relates to a friction stir welding tool used for friction stir welding and a friction stir welding method.

  In friction stir welding, a probe (rod-like protrusion, pin) equipped on a friction stir welding tool is pressed against a work joint while rotating and immersed in the work, so that friction heat is applied to the work joint. This is a technique for softening the joint and generating a plastic flow region of the work material around the probe by the rotational force of the probe, stirring and mixing, and joining a plurality of works integrally. It has been used mainly for the joining of aluminum alloy material thin plates (10 mm or less) that have a small joining reaction force during friction stir welding.

  The friction stir welding tool used for the friction stir welding has a shoulder on the proximal end side of the probe for immersing in the joint portion of the workpiece, with a diameter larger than that of the probe and in contact with the surface near the joint portion of the workpiece. A type that is provided integrally and rotates the shoulder integrally with the probe has been mainly used.

  The shoulder has a function of generating frictional heat by contacting the surface of the workpiece while rotating, and heating the vicinity of the joint where the probe is immersed in the workpiece. In recent years, it has been found that the plastic flow region formed in the joint portion of the workpiece by the rotating probe exhibits a function of pressing so as not to protrude outside the surface of the workpiece.

  Therefore, as one type of friction stir welding tool, as a configuration in which a fixed shoulder having a through-hole through which the rotation drive shaft of the probe is inserted is provided on the proximal end side of the probe, the workpiece is rotated while the probe is rotated. There has been proposed a friction stir welding tool of a type in which the shoulder is simply pressed without being rotated against the workpiece when immersed in the workpiece (see, for example, Patent Document 1 and Patent Document 2).

  As another type of friction stir welding tool, a so-called bobbin tool having a pair of shoulders on both sides in the axial direction of the probe has been developed. As such a bobbin tool, by setting the interval between the shoulders to be a predetermined amount smaller than the plate thickness dimension of the workpiece, each shoulder can be pressed against both surfaces of the workpiece with a predetermined pressing force without requiring an external force. In order to be able to cope with fluctuations in the plate thickness of the workpiece, there has been conventionally proposed a technique in which the distance between the pair of shoulders on both ends in the axial center direction of the probe is variable (for example, Patent Documents) 3).

  Furthermore, when a gap exists in the joint of the workpiece, even if a plastic flow region is formed in the joint by the probe of the friction stir welding tool, the amount of the workpiece material itself that is plastically flowed is Since it is originally insufficient to close the gap, poor bonding occurs. Therefore, it has been considered to supply a melt (melting material) when performing friction stir welding.

  As a method for supplying the molten material, there is a method for supplying the molten material to the surface of the region near the joint heated by the rotating shoulder and the probe or supplying the molten material through the molten material supply passage provided in the probe. Conventionally proposed (see, for example, Patent Document 4).

  Also, as another method for supplying the molten material, when performing friction stir welding of the joint portion of the workpiece (material to be joined), the molten material (filler) is supplied to the gap formed in the joint portion. Has been conventionally proposed (see, for example, Patent Document 5).

  As described above, when supplying a molten material to fill the gap between the workpiece joints during friction stir welding, it is usually the same as the workpiece, unless a special function is required for the joint portion. In the case of joining materials of different materials or workpieces of different materials, it is desirable to use a material of the same material as one of the workpieces.

Special table 2009-537325 gazette Japanese Patent No. 4240579 Japanese Patent No. 3735298 JP 2007-7729 A JP 2005-111533 A

  However, among the methods shown in Patent Document 4, the method in which the powdered molten material is arranged on the surface of the region near the joint by being heated by the rotating shoulder and the probe is, for example, part of the powder of the molten material. Even if softening is caused by frictional heat with the shoulder, the softened powder of powder is surely reached to the region where the plastic flow around the probe is generated through the gap between the work and the shoulder being pressed against the work. There is no means to send it to. Therefore, in the above method, it is difficult to fill the gap existing in the joint portion between the workpieces with the above-described melt material during the friction stir welding.

  Of the methods disclosed in Patent Document 4, the method of supplying the melt through the melt supply passage provided inside the probe needs to have a structure in which the probe is provided through the melt supply passage. In addition, since a mechanism for extruding the softened material in the melt supply passage of the probe from the melt supply passage to the plastic flow region around the probe is required, the apparatus configuration of the friction stir welding apparatus is There is a problem of increasing complexity. Furthermore, this method has a problem that it becomes difficult to manage the supply of the molten material.

  The technique described in Patent Document 5 is to supply a molten material to a gap formed in a workpiece joining line at the time of friction stir welding. Since it is only supplied to the part where the shoulder is separated from the surface, that is, the part where frictional heat with the shoulder is not generated in the work, it is difficult to soften the molten material itself.

  In addition, in the technique disclosed in Patent Document 5, even if the molten material is softened, the softened molten material is likely to be pushed out to the outer periphery of the shoulder when it contacts the rotating shoulder. Therefore, with this method, it is difficult to reliably feed the softened molten material to the plastic flow region around the probe.

  In Patent Document 1 and Patent Document 2, the idea of supplying the molten material at the time of the friction stir welding is not shown at all, and there is no suggestion at all.

  In addition, since the ones shown in Patent Literature 1 and Patent Literature 2 are provided with a fixed shoulder only on the base end side of the probe, the workpiece is heated with frictional heat due to friction with the shoulder. Therefore, since the amount of heat input to the workpiece is small, it is difficult to apply it to the joining of workpieces with a large plate thickness.

  The above-mentioned Patent Document 3 does not show any idea of supplying the molten material at the time of performing the friction stir welding, and there is no suggestion at all. In addition, since the rotating shoulder of the bobbin tool is in contact with both the front and back surfaces of the workpiece, it is difficult to supply the melt from the outside of the rotating shoulder to the plastic flow region around the probe.

  Therefore, conventionally, when there is a gap in the joint portion of a workpiece having a large plate thickness, an apparatus configuration and method for realizing good friction stir welding while supplying a molten material has not been proposed. Is real.

  Therefore, the present invention provides a friction stir welding tool capable of performing good friction stir welding while reliably supplying a molten material even when a gap is generated in a joint portion of a thick workpiece, and An object of the present invention is to provide a friction stir welding method.

  In order to solve the above-mentioned problems, the present invention, corresponding to claim 1, is provided with a probe longer than the plate thickness of the workpiece and one surface of the workpiece provided on one end side in the axial direction of the probe. And a fixed shoulder for contacting the other surface of the workpiece, the fixed shoulder includes an opening for inserting the probe, and the fixed shoulder. A melt guide that communicates with the opening on the work contact surface side of the shoulder, and further, a rod-shaped melt is directed toward the probe disposed inside the opening of the fixed shoulder through the melt guide. A friction stir welding tool having a configuration including a melt supply means for energizing and supplying is provided.

  In the above configuration, the melt supply means has a function of controlling the pressure so that the pressure of pressing the rod-shaped melt against the probe is constant.

  Furthermore, in each said structure, it is set as the structure which connected and fixed the melt supply means to the fixed type shoulder.

  Furthermore, in each of the above configurations, a rotational drive shaft for rotationally driving the probe and the shoulder is attached to the other end side in the axial direction of the probe inserted and arranged in the opening of the fixed shoulder. To do.

  Further, in accordance with claim 5, a probe longer than the plate thickness of the workpiece and a shoulder provided on one end side in the axial direction of the probe are rotationally driven, and the rotation is performed on one surface of the workpiece. The rotating probe is attached to the other surface of the workpiece with a fixed shoulder having an opening through which the other end side of the probe in the axial direction is inserted. When immersing into the joint and moving along the joint line, through the melt guide provided to communicate the rod-shaped melt from the melt shoulder to the opening on the work contact surface side from the fixed shoulder, The friction stir welding method is configured to urge and supply the probe to the probe disposed inside the opening.

According to the present invention, the following excellent effects are exhibited.
(1) A probe that is longer than the plate thickness of the workpiece and a shoulder that is provided on one end side in the axial direction of the probe and is brought into contact with one surface of the workpiece are rotatably driven. A fixed shoulder for contacting the other surface, the fixed shoulder having an opening for inserting the probe, and a melt guide communicating with the opening on the work contact surface side of the fixed shoulder; Friction having a configuration further comprising a melt supply means for biasing and supplying a rod-shaped melt through the melt guide toward the probe disposed inside the opening of the fixed shoulder Since it is used as a stir welding tool, the probe to be rotated can be immersed over the entire thickness of the workpiece. Further, the work can increase heat input by frictional heat generated by bringing the shoulder to be rotated into contact with one surface side of the work. Therefore, even when the workpiece is thick, good friction stir welding can be performed.
(2) The rod-like molten material supplied by being urged from the molten material supply means through the molten shoulder guide is friction caused by contact with a probe in a rotationally driven state disposed inside the opening of the fixed shoulder. The tip of the molten material can be surely softened by heat. In this state, when there is no gap in the workpiece joint, there is no place for the softened melt, but when there is a gap in the workpiece joint, the softened melt is directly below it. The workpiece can be fed into the plastic flow region of the workpiece material formed on the outer periphery of the probe. The feeding of the softened molten material into the plastic flow region can be continuously performed until the plastic flow region is filled between the fixed shoulders disposed on both sides of the workpiece. . Therefore, even if there is a gap in the joint portion of the workpiece, friction stir welding without joint failure can be performed.
(3) While rotating and driving a probe longer than the plate thickness of the workpiece and a shoulder provided on one end side in the axial direction of the probe, the rotating shoulder is brought into contact with one surface of the workpiece, With the other surface of the workpiece in contact with a fixed shoulder having an opening through which the other end side of the probe in the axial direction is inserted, the rotating probe is immersed in the joint of the workpiece, When moving along the joining line, the rod-shaped molten material is disposed inside the opening from the molten material supply means through the molten material guide provided to communicate with the opening on the work contact surface side on the fixed shoulder. Since this is a friction stir welding method in which the probe is biased and supplied toward the probe, the same effects as in the above (1) and (2) can be obtained.

1 shows an embodiment of a friction stir welding tool and a friction stir welding method of the present invention, in which (a) is a partially cut schematic side view, (b) is an AA direction arrow view of (a), ( c) is a BB direction arrow view of (a). (A) (b) (c) is a figure corresponding to Drawing 1 (a) which shows another example of the melt supply means in the friction stir welding tool of Drawing 1, respectively. It is a partially cut schematic side view which shows the other form of implementation of this invention. It is a partially cut away schematic side view which shows other form of implementation of this invention.

  Hereinafter, embodiments for carrying out the present invention will be described with reference to the drawings.

  1 (a), (b), (c) and FIGS. 2 (a), (b), and (c) show an embodiment of the friction stir welding tool of the present invention.

  That is, the friction stir welding tool of the present invention includes a probe 2 that is longer than the plate thickness of the workpiece 10 to be joined, as shown by reference numeral 1 in FIGS. A shoulder 3 connected to one end side in the axial direction of 2 and brought into contact with one surface of the workpiece 10, and a rotational drive for transmitting a rotational drive force by a rotational drive device (not shown) to the probe 2 and the shoulder 3 A fixed shoulder 5 for contacting the shaft 4 and the other surface of the workpiece is provided.

  The fixed shoulder 5 includes an opening 6 through which the probe 2 is inserted and arranged, and a guide groove 7 serving as a melt guide communicated with the opening 6 on the surface side of the fixed shoulder 5 that contacts the workpiece 10. It is set as the structure provided with.

  Furthermore, the friction stir welding tool 1 according to the present invention urges a rod-shaped molten material (melting material) 9 toward the probe 2 disposed inside the opening 6 through the guide groove 7 of the fixed shoulder 5. It is set as the structure provided with the melt supply means 8 for supplying in a state.

  More specifically, the probe 2 has a length in the axial direction that is at least as long as the thickness of the rod-shaped molten material 9 than the thickness of the workpiece 10 that is supposed to be joined. It is set to.

  The orientation of the probe 2 in the axial direction is such that, for example, when the two workpieces 10 arranged in a horizontal plane are brought into contact with each other and joined, the axial direction is the vertical direction.

  Furthermore, the probe 2 has a shoulder 3 in the form of a disk having a diameter larger than that of the probe 2 on one end side in the axial direction which is the lower end side in FIG. Has been.

  One end (lower end) of the rotary drive shaft 4 extending in the vertical direction is integrally connected to the other end side (the upper end side in FIG. 1A) of the probe 2 to which the shoulder 3 is integrally connected. A rotation drive device (not shown) is connected to the other end side of the rotation drive shaft 4 (the upper end side in FIG. 1A). Thereby, when the rotational drive shaft 4 is rotationally driven by the rotational drive device, the probe 2 and the shoulder 3 can be rotationally driven together.

  The fixed shoulder 5 has a flat plate shape with a work contact surface (lower surface in FIG. 1A), and an opening 6 having an inner diameter slightly larger than the outer diameter of the probe 2 is provided near the center thereof. In FIG. 1A, it is provided so as to penetrate in the vertical direction. As a result, the fixed shoulder 5 is configured such that the shoulder 3 provided on one end side in the axial center direction of the probe 2 is brought into contact with the lower surface as one surface of the work 10 and the other end side portion of the probe 2 is placed. Can be arranged along the upper surface of the workpiece 10 by being inserted through the opening 6.

  The fixed shoulder 5 is attached to a lifting mechanism (not shown) for a fixed shoulder via a support member 11 attached to a surface opposite to the workpiece 10 (upper surface in FIG. 1A). It has been.

  Further, the upper end side of the rotary drive shaft 4 is connected to a lift mechanism (not shown) for the rotary drive shaft for raising and lowering the rotary drive shaft 4 without hindering rotation by the rotary drive device (not shown). Yes.

  As shown in FIG. 1A, the separate elevating mechanisms are configured such that the upper surface of the shoulder 3 attached to the lower end side of the rotational drive shaft 4 via the probe 2 is in contact with the lower surface of the workpiece 10, and From the position where the lower surface of the fixed shoulder 5 comes into contact with the upper surface of the workpiece 10, the shoulder 3 can be urged in the pulling direction, and the fixed shoulder 5 can be urged in the pressing direction. In other words, each of the elevating mechanisms can be urged in a direction in which the distance between the upper surface of the shoulder 3 and the lower surface of the fixed shoulder 5 is narrowed. Thereby, when the workpiece 10 is inserted and disposed in the gap between the upper surface of the shoulder 3 and the lower surface of the fixed shoulder 5, the shoulder 3 and the fixed shoulder 5 are respectively placed on the lower surface and the upper surface of the workpiece 10. It can be pressed with a predetermined pressing pressure. Further, each of the elevating mechanisms can freely control the pressing pressure of the shoulder 3 and the fixed shoulder 5 against the work 10.

  The lifting mechanisms of the shoulder 3 and the fixed shoulder 5 are preferably attached to a common support frame. In such a configuration, a reaction force when the shoulder 3 is pressed against the lower surface of the workpiece 10 and a reaction force when the fixed shoulder 5 is pressed against the upper surface of the workpiece between the elevating mechanisms are interposed via the support frame. Since they can be transmitted to each other and cancelled, the reaction force can be prevented from acting on the friction stir welding apparatus other than the support frame of each lifting mechanism.

  Further, the fixed shoulder 5 is provided on the lower surface serving as a contact surface with the workpiece 10, for example, on the front side surface in the traveling direction of the friction stir welding tool 1 of the present invention when the fixed shoulder 5 is friction stir welded. The guide groove 7 is provided so as to extend linearly from the melt inlet 12 that opens to the melt outlet 13 that communicates with the opening 6.

  The guide groove 7 has a cross-sectional shape in a plane orthogonal to the longitudinal direction corresponding to a cross-sectional shape orthogonal to the longitudinal direction of the melt 9.

  The molten material supply means 8 is disposed at a position on the extension line of the guide groove 7 of the fixed shoulder 5 and is configured to grip and hold the proximal end side of the rod-shaped molten material 9.

  The rod-shaped molten material 9 is inserted into the guide groove 7 of the fixed shoulder 5 from the molten material inlet 12 to the molten material outlet 13, and one end in the longitudinal direction at the tip is inside the opening 6 of the fixed shoulder 5. It is arranged so as to hit 2.

  The melt supply means 8 holds the rod-like melt 9 near the other end in the longitudinal direction, which is near the base end, and can be urged so as to press the melt 9 toward the probe 2.

  The biasing means for biasing the melt 9 of the melt supply means 8 toward the probe 2 is detachable at a position near the other end in the longitudinal direction of the melt 9 as shown in FIG. And a fluid pressure cylinder 16 such as a telescopic air pressure or hydraulic pressure interposed between the clamp 14 and the support structure 15 on the fixed side. The fluid pressure cylinder 16 clamps the clamp 14. The melt 9 is moved in the longitudinal direction via

  Further, as shown in FIG. 2 (a), the urging means includes a clamp 14 similar to the above that holds a position near the other end in the longitudinal direction of the molten material 9, and a support structure 15 that is on the fixed side of the clamp 14. And a clamp 14 similar to the above for holding the position near the other end in the longitudinal direction of the molten material 9 as shown in FIG. 2 (b). Moreover, it is good also as a structure attached to the ball screw mechanism 18 which operate | moves in the direction along the longitudinal direction of this molten material 9. It is assumed that the ball screw mechanism 18 is installed on a support structure on the fixed side (not shown).

  Further, as another form of the urging means for the molten material 9, as shown in FIG. 2 (c), a pair of rollers 19 for sandwiching a portion near the other end in the longitudinal direction of the molten material 9 is provided, A configuration in which at least one of the rollers 19 is a driving roller connected to a rotation driving device (not shown) such as a motor, and the melt 9 sandwiched between a pair of rollers 19 is sent out toward the probe 2. It is good.

  The urging means of the molten material supply means 8 is a supply pressure when supplying the molten material 9 while being urged toward the probe 2 with respect to the molten material 9 arranged so that the tip is in contact with the probe 2. It is preferable to provide a function capable of controlling the pressure so that the pressure of the molten material 9 against the probe 2 becomes constant. As the function of this pressure control, for example, in the fluid pressure cylinder 16 as shown in FIG. 1 (a), the pressure chamber on the side where the fluid pressure cylinder 16 is operated in the feed direction of the melt 9, in the drawing, on the extension operation side. What is necessary is just to keep the fluid pressure supplied to a pressure chamber constant.

  Further, the pressure control function is as follows. As shown in FIG. 2 (c), the molten material supply means 8 having a roller 19 for feeding the molten material 9 is used so that the tip of the molten material 9 abuts against the probe 2. In a state where 9 is arranged, a constant driving torque may be applied to at least one roller 19 serving as a driving roller by a rotary driving device (not shown).

  The melt supply means 8 is connected to the fixed shoulder 5 or the support member 11 of the fixed shoulder 5 via a connecting member (not shown) to fix the relative position with the fixed shoulder 5. A configuration is preferable. With such a configuration, even when the fixed shoulder 5 is moved for the purpose of corresponding to the position of the joining line of the workpiece 10, the molten material supply means 8 is provided with the guide groove 7 of the fixed shoulder 5. It can be located on the extension line. Thereby, since the operation | work which positions separately can be made unnecessary, the reduction at the time of implementing friction stir welding can be aimed at.

  Further, the fixed shoulder 5 is provided with a portion of the guide groove 7 near the end portion on the side away from the opening 6, that is, above the portion near the melt inlet 12 in the guide groove 7. A notch 20 communicating with the upper surface side is provided, and a pressing roller 21 having a rotation shaft in a direction orthogonal to the guide groove 7 is disposed in the notch 20. The pressing roller 21 has a rotation shaft that is rotatably held by a holder 22. Furthermore, the holder 22 is connected to a lifting mechanism (not shown). As a result, in the notch 20 portion of the fixed shoulder 5, when the rod-like molten material 9 is disposed through the guide groove 7 from the molten material inlet 12 to the molten material outlet 13, the lifting and lowering (not shown) is performed. By lowering the pressing roller 21 from above by a mechanism, the molten material 9 can be pressed against the upper surface of the workpiece 10 with a predetermined pressure.

  When performing the friction stir welding using the friction stir welding tool 1 of the present invention having the above configuration, first, the probe 2 is brought into contact with or near the end face of the workpiece 10 at one end side of the workpiece joining line. Arrange as follows.

  Next, in the friction stir welding tool 1 of the present invention, the shoulder 3 and the fixed shoulder 5 are arranged so as to sandwich the workpiece 10 from both sides. At this time, the shoulder 3 and the fixed shoulder 5 are pressed against the workpiece 10 with a predetermined pressure by controlling the position or pressure of the corresponding lifting mechanism. For example, the fixed shoulder 5 is positioned by controlling the position of the corresponding lifting mechanism so that the lower surface of the fixed shoulder 5 contacts the upper surface of the workpiece 10. Thereafter, the shoulder 3 is pulled up by an elevating mechanism connected to the upper end side of the rotary drive shaft 4. At this time, pressure control of the elevating mechanism is performed, and the shoulder 3 is fixed to the lower surface of the work 10. Positioning is performed so that it can be pressed in a state in which a pressure of 5 is applied.

  Next, the rod-shaped melt 9 delivered from the melt supply means 8 is inserted into the guide groove 7 of the fixed shoulder 5 from the melt inlet 12 to the melt outlet 13, and the tip of the melt 9 is fixed to the fixed shoulder 5. The probe 2 is arranged in contact with the portion near the upper end of the probe 2 protruding above the upper surface of the workpiece 10.

  Further, the pressing roller 21 is disposed so as to press the molten material 9 inserted into the guide groove 7 of the fixed shoulder 5 against the upper surface of the work 10 with a predetermined pressure.

  As will be described later, the probe 2 and the shoulder 3 are rotationally driven by a rotational drive device (not shown) at any time before starting relative movement along the joining line of the workpiece 10 of the friction stir welding tool 1 of the present invention. The rotation drive integrated with the shaft 4 is started.

  In this state, the friction stir welding tool 1 of the present invention starts relative movement along the joining line of the workpiece 10. This relative movement is performed so that the workpiece 10 fixed on the moving table (not shown) moves in the direction along the bonding line of the workpiece 10 together with the moving table with respect to the friction stir welding tool 1 fixed in position. Alternatively, the friction stir welding tool 1 may be moved along the joining line of the workpiece 10 whose position is fixed.

  As a result, in the state in which the workpiece 10 is heated from the lower surface side in the vicinity of the joining line of the workpiece 10 by the frictional heat with the rotationally driven shoulder 3, the rotationally driven probe 2 is positioned at the joining line position. It comes to be pressed against the end face of. For this reason, the material of the part of the work 10 in contact with the rotating probe 2 is plastically flowed, and the probe 2 is immersed in the joint part of the work 10.

  As described above, the joint portion of the workpiece 10 has a thickness of the workpiece 10 around the probe 2 by the immersion of the rotating probe 2 in a portion heated by frictional heat with the shoulder 3. A plastic flow region is formed over the entire surface, whereby friction stir welding of the joint portion of the workpiece 10 is started.

  When the friction stir welding is started as described above, the friction stir welding tool 1 of the present invention is the rod-shaped melted material arranged in the guide groove 7 of the fixed shoulder 5 by the melt supply means 8. 9 is urged toward the probe 2 rotating inside the opening 6 of the fixed shoulder 5. For example, the bias controls the supply pressure so that the melt 9 is pressed against the probe 2 with a constant pressing pressure. As a result, the tip of the molten material 9 is heated by the frictional heat generated by friction with the probe 2, so that the tip of the molten material 9 is softened.

  Thereafter, as the friction stir welding tool 1 of the present invention relatively moves along the joining line of the workpiece 10, the friction stirring joining along the joining line of the workpiece 10 is continuously performed.

  When the friction stir welding is performed, if there is no gap in the joint portion of the workpiece 10, the material of the softened workpiece 10 that plastically flows around the probe 2 between the shoulder 3 and the fixed shoulder 5. Is present to be filled. In this case, as described above, it is assumed that the melt 9 supplied from the melt supply means 8 to the guide groove 7 of the fixed shoulder 5 is urged toward the probe 2 with its tip end softened. However, the cross-sectional shape of the guide groove 7 corresponds to that of the melt 9, the probe 2 exists inside the opening 6, and the plasticity around the probe 2 below the fixed shoulder 5. Since the flowing region is filled with the material of the softened workpiece 10 as described above, there is no place to go. Therefore, the melt 9 is held in the guide groove 7 of the fixed shoulder 5 as it is.

  On the other hand, when friction stir welding is performed, if there is a gap in the joint portion of the workpiece 10, the amount of the material of the softened workpiece 10 that plastically flows around the probe 2 is fixed to the shoulder 3. The amount filled between the shoulder 5 is insufficient.

  Therefore, in this case, the softened portion on the tip side of the melt 9 supplied to the guide groove 7 of the fixed shoulder 5 is positioned immediately below the pressure applied by the melt supply means 8. It is fed into the plastic flow region around the probe 2 and is plastically flowed together with the material of the softened workpiece 10.

  Since the melt 9 is urged by the melt supply means 8, as described above, when the softened portion on the tip side of the melt 9 is fed into the plastic flow region around the probe 2, the melt 9 is fed. As a result, the melt 9 is sequentially supplied to the guide groove 7, and the portion that becomes a new tip is softened by frictional heat due to friction with the rotating probe 2. Therefore, the amount of the material of the softened workpiece 10 that plastically flows around the probe 2 is filled between the shoulder 3 and the fixed shoulder 5 in the plastic flow region around the probe 2. The plastic flow region is sequentially fed until the amount reached is reached.

  Thereafter, when the amount of the material of the softened workpiece 10 that plastically flows around the probe 2 reaches the amount filled between the shoulder 3 and the fixed shoulder 5, the molten material 9 has no place to go. The feeding of the molten material 9 to the plastic flow region is automatically stopped.

  Since the amount of the molten material 9 fed into the plastic flow region around the probe 2 corresponds to the volume of the gap that existed in the joint portion of the workpiece 10, the friction in the state in which the molten material 9 is fed. In the stir-bonded portion, no bonding failure due to the gap occurs.

  After that, when the friction stir welding tool 1 of the present invention moves relative to the entire length of the joining line of the workpiece 10, the friction of the joining portion of the workpiece 10 is obtained at a location where no gap exists in the joining portion of the workpiece 10. In the place where the stir welding is performed and there is a gap in the joint portion of the workpiece 10, the friction stir welding is performed in a state in which the gap is filled by the automatic feeding of the molten material 9 as described above. .

  As described above, according to the friction stir welding tool 1 of the present invention, when there is a gap in the joint portion of the workpiece 10 that performs friction stir welding, the plastic flow region formed on the outer periphery of the probe 2 is The amount of the melt 9 that fills the gap can be reliably supplied. Therefore, it is possible to eliminate the possibility that a bonding failure caused by the gap existing in the bonded portion of the workpiece 10 occurs in the friction stir bonded region.

  Further, when the molten material 9 is fed into the plastic flow region of the material of the workpiece 10 on the outer periphery of the probe 2, the fixed shoulder 5 and the shoulder 3 are arranged on both upper and lower sides of the plastic flow region. Therefore, there is no possibility that the melt 9 is excessively supplied to the plastic flow region. Therefore, in the friction stir welding tool 1 of the present invention, the supply management of the melt 9 can be facilitated.

  If the molten material supply means 8 has a function of controlling the pressing pressure of the molten material 9 against the probe 2 to be constant, the molten material 9 is fed into a place where a gap exists in the joint portion of the workpiece 10. Regardless of the amount consumed, when the friction stir welding is performed at a location where there is a gap in the joint portion of the workpiece 10, the melt 9 can be supplied in a fixed amount. Therefore, the supply management of the melt 9 can be made easier.

  The friction stir welding tool 1 of the present invention can form a plastic flow region over the entire plate thickness of the workpiece 10 by the probe 2. Furthermore, the friction stir welding tool 1 according to the present invention is provided on one end side in the axial direction of the probe 2 and is rotated integrally with the probe 2 so that the joint portion of the workpiece 10 is frictionally heated from the lower surface side. Since it can heat, the heat input with respect to the junction part of this workpiece | work 10 can be increased. As a result, the friction stir welding tool 1 of the present invention can perform friction stir welding even for a workpiece 10 having a large plate thickness, and causes a defect such as a kissing bond in the joined portion of the workpiece 10. Thus, it is possible to perform good friction stir welding without any problem, and further, it is possible to increase the speed of the friction stir welding.

  The rotational drive shaft 4 for rotationally driving the probe 2 and the shoulder 3 is attached to the other end side (upper end side) of the probe 2 arranged in the opening 6 of the fixed shoulder 5 in the axial direction. An elevating mechanism for elevating the probe 2 and the shoulder 3 via the rotational drive shaft 4 is disposed above the one side of the workpiece 10 together with an elevating mechanism for elevating the fixed shoulder 5. Can do. Accordingly, since each of the lifting mechanisms can be provided on one side of the workpiece, the reaction force when the shoulder 3 is brought into contact with the lower surface of the workpiece 10 with a predetermined contact pressure by the corresponding lifting mechanism, It is possible to easily construct a configuration in which each lifting mechanism transmits the reaction force when the fixed shoulder 5 is brought into contact with the upper surface of the workpiece 10 with a predetermined contact pressure by the corresponding lifting mechanism. Therefore, it is not necessary to receive a large reaction force in the friction stir welding apparatus, and the apparatus configuration can be reduced in size.

  In the said embodiment, the structure provided with the guide groove 7 along the lower surface of this fixed type shoulder 5 was shown as a molten material guide for penetrating and arrange | positioning the rod-shaped molten material 9. As shown in FIG. Such a configuration is preferable in terms of easy processing. However, if the melt outlet 13 is arranged at the lower surface side end portion that is the workpiece contact surface side end portion of the opening 6 in the fixed shoulder 5, FIG. 3, the fixed shoulder 5 has a through hole extending obliquely from the melt inlet 12 (shown in the case of the side in the figure) to the melt outlet 13 provided on the side or top surface of the fixed shoulder 5. It is good also as a structure which pierces and uses this through-hole as the melt guide 7a. The cross-sectional shape of the melt guide 7a may be set so as to correspond to the cross-sectional shape of the rod-shaped melt 9. Although not shown, the melt supply means 8 may be disposed at a position on the extension line of the melt guide 7a of the fixed shoulder 5.

  In each of the above embodiments, the guide groove 7 and the melt guide 7a for guiding the rod-shaped melt 9 are shown as an arrangement extending forward in the tool traveling direction with respect to the opening 6 in the fixed shoulder 5. The guide groove 7 and the melt guide 7a may be provided so as to extend in any direction in the circumferential direction from the opening 6. Also in this case, the melt supply means 8 may be disposed at a position on the extension line of the guide groove 7 of the fixed shoulder 5 or the melt guide 7a.

  In the above-described embodiment, the pressing roller 21 is shown as being configured to be lifted and lowered independently of the fixed shoulder 5 by a lifting mechanism (not shown) connected to the holder 22, but the pressing roller 21 is shown in FIG. As described above, the rotating shaft may be directly attached to the fixed shoulder 5 and may be moved up and down integrally with the fixed shoulder 5.

  Further, the pressing roller 21 is preferably equipped. For example, when the fixed shoulder 5 is provided with the melt guide 7a that is a through hole extending in an oblique direction as described above, the pressing roller 21 is omitted. It is good also as the structure which carried out.

  In the said embodiment, the shoulder 3 and the fixed shoulder 5 which rotate integrally with the probe 2 were shown as a structure which can be raised / lowered by an individual raising / lowering mechanism, respectively. Such a configuration is preferable in that the distance between the shoulder 3 and the fixed shoulder 5 can be adjusted to easily cope with the workpiece 10 having a different thickness. On the other hand, when applied to a friction stir welding apparatus of a type that targets only workpieces 10 having a constant plate thickness, the friction stir welding tool 1 of the present invention is not shown, but the fixed shoulder 5 is not shown. The opening 6 is configured to hold a predetermined portion of the probe 2 and the rotational drive shaft 4 of the shoulder 3 in the axial direction via a bearing or the like so that the shoulder 3 and the fixed shoulder 5 can be rotated. The interval may be fixed at an interval corresponding to the plate thickness of the workpieces 10 to be joined.

  The present invention is not limited only to the above-described embodiment, and the rod-like molten material 9 is shown as a round rod-shaped material. However, the rod-shaped molten material 9 having a polygonal cross section such as a square bar shape is used. May be.

  As long as the fixed shoulder 5 can be connected to the corresponding lifting mechanism, the attachment position of the support member 11 to the fixed shoulder 5 may be changed as appropriate. Further, the shape of the support member 11 may be changed as appropriate.

  The melt supply means 8 urges the rod-shaped melt 9 inserted in the guide groove 7 of the fixed shoulder 5 or the melt guide 7 a toward the probe 2 disposed in the opening 6 of the fixed shoulder 5. If possible, the fluid pressure cylinder 16 (FIG. 1A), the spring member 17 (FIG. 2A), the ball screw mechanism 18 (FIG. 2B), and the feeding roller 19 (FIG. 2C) Any urging means other than)) may be provided.

  In the illustrated friction stir welding tool 1 of the present invention, the size of each constituent member and the dimensional ratio between the constituent members are for convenience of illustration and do not reflect the actual size or dimensional ratio.

  The friction stir welding tool 1 of the present invention may be used in any posture depending on the posture in which the top and bottom are inverted, the posture of 90 ° lateral orientation, and the posture of the workpiece 10 to be joined.

  In addition, the friction stir welding tool 1 of the present invention can maintain the relative positions of the probe 2 and the shoulder 3 and the fixed shoulder 5 when moving relative to the workpiece 10 in the tool moving direction. The rotational drive shaft 4 for rotationally driving the probe 2 and the shoulder 3 may be attached to the axial end surface of the shoulder 3 opposite to the probe 2 attachment side.

  Of course, various modifications can be made without departing from the scope of the present invention.

DESCRIPTION OF SYMBOLS 1 Friction stir welding tool 2 Probe 3 Shoulder 4 Rotation drive shaft 5 Fixed shoulder 6 Opening 7 Guide groove (melting material guide)
7a Melting material guide 8 Melting material supply means 9 Melting material 10 Workpiece

Claims (5)

A probe that is longer than the plate thickness of the workpiece, and a shoulder that is provided on one end side in the axial direction of the probe to contact one surface of the workpiece are rotatably driven,
A fixed shoulder for contacting the other surface of the workpiece,
The fixed shoulder includes an opening for inserting the probe, and a melt guide communicating with the opening on the work contact surface side of the fixed shoulder,
Furthermore, it has a configuration comprising a melt supply means for biasing and supplying a rod-shaped melt through the melt guide toward the probe disposed inside the opening of the fixed shoulder. Friction stir welding tool.   The friction stir welding tool according to claim 1, wherein the melt supply means has a function of controlling the pressure so that the pressing pressure of the rod-shaped melt on the probe is constant.   The friction stir welding tool according to claim 1 or 2, wherein the melt supply means is connected and fixed to a fixed shoulder.   The friction according to claim 1, 2 or 3, wherein a rotational drive shaft for rotationally driving the probe and the shoulder is attached to the other end side in the axial direction of the probe inserted through the opening of the fixed shoulder. Stir welding tool. Rotate and drive a probe that is longer than the plate thickness of the workpiece and a shoulder provided on one end of the probe in the axial direction,
A state in which the rotating shoulder is brought into contact with one surface of the workpiece, and a fixed shoulder having an opening through which the other end side of the probe in the axial direction is inserted into the other surface of the workpiece. Then, when immersing the rotating probe in the joint of the workpiece and moving it along the joining line,
From the melt supply means, a rod-shaped melt is urged toward the probe disposed inside the opening through a melt guide provided to communicate with the opening on the work contact surface side of the fixed shoulder. Friction stir welding method characterized by being supplied.

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