Patent Application
20220134471
The present disclosure relates to a friction stir welding apparatus and a friction stir welding method that are capable of joining a first workpiece and a second workpiece to form a T-shaped structure in which the second workpiece is butted against the first workpiece such that the second workpiece is upright on the first workpiece.
Friction stir welding (FSW) is one of the methods for joining workpieces together that are made of a metal or the like. A rotary tool is plunged into a position at which the workpieces are to be joined together, and frictional heat is generated at the position, which causes a plastic flow of the metal or the like, and thereby these workpieces are joined together. There are various types of workpiece joint structures. For example, friction stir welding is used to join one workpiece to another workpiece to form a T-shaped structure (a T-joint) in which the one workpiece is joined to the other workpiece such that the one workpiece is upright on the other workpiece. In the case of joining workpieces together to form such a T-shaped structure, at a butted portion formed by the workpieces butted together, inner corners of the butted portion, the inner corners serving as the “proximal end” portion of the upright workpiece, are subjected to friction stir welding.
As one example of a known joining technique utilizing friction stir welding for forming a T-shaped structure, Patent Literature 1 discloses a friction stir welding apparatus. The friction stir welding apparatus includes: stationary shoulders that come into contact with a pair of inner corners, respectively; a pair of friction stir welding tools that are provided on the respective stationary shoulders, the friction stir welding tools being disposed at both sides of an upright member (upright workpiece) such that the upright member is positioned between the friction stir welding tools and such that the friction stir welding tools are positioned opposite each other; and a moving mechanism that causes the stationary shoulders and the friction stir welding tools to make relative movement along a butted portion. The upright member is positioned between the stationary shoulders, and each stationary shoulder is positioned at the opposite side of the upright member from the friction stir welding tool of the other stationary shoulder. The positions of the stirring axes of the respective friction stir welding tools are deviated from each other in the relative movement direction.
The friction stir welding apparatus disclosed in Patent Literature 1 includes a pair of rotary tools for performing friction stir welding from both sides of the upright member. Therefore, it is necessary to control the driving of each of the rotary tools. This consequently makes the apparatus configuration complex and results in a high cost.
In Patent Literature 1, one of the stationary shoulders, when seen from the friction stir welding tool provided on the other stationary shoulder, functions as a pressing member that presses one of the inner corners while moving along the butted portion. It has been found that in the configuration in which while the friction stir welding tools are being moved, friction stir welding is performed on one of the inner corners and the other inner corner is pressed by the movable pressing member, deformations occur at the inner corners of the workpieces.
Specifically, since the pressing member presses the inner corner while moving, part of the workpieces softened by the friction stir welding tends to adhere to the pressing surface of the pressing member. If the workpieces adhere to the pressing member in such a manner, deformations (or flaws) such as galling, tears, and burrs occur on the surface of the inner corner (i.e., the surface pressed by the pressing member).
In light of this, it is conceivable to use not the movable pressing member, but a fixed-type pressing member that presses the entire inner corner along the butted portion. In this case, however, the pressing member would be elongated and the weight of the pressing member would be increased in order to press the entire inner corner sufficiently. In addition, such a fixed-type pressing member needs to be fixed at its both ends to prevent positional deviation of the pressing member at the time of joining. Accordingly, the more the pressing member is elongated (i.e., the longer the butted portion is), the greater is the size of the fixing means. For these reasons, the use of a fixed-type pressing member causes an increase in the size of the friction stir welding apparatus.
The present disclosure has been made to solve the above-described problems. An objective of the present disclosure is to provide a friction stir welding apparatus and a friction stir welding method that make it possible to, when performing friction stir welding on a butted portion where workpieces are butted together, effectively avoid deformations or the like at inner corners of the butted portion and suppress, for example, an increase in the configuration complexity of the apparatus, an increase in the size of the apparatus, or an increase in cost.
In order to solve the above-described problems, a friction stir welding apparatus according to the present disclosure is a friction stir welding apparatus for use in friction stir welding performed on a butted portion where a second workpiece is butted against a first workpiece such that the second workpiece is upright on the first workpiece. The friction stir welding apparatus includes: a rotary tool that is plunged into one inner corner of a pair of inner corners that are positioned, at the butted portion, on both sides of the second workpiece, respectively; an inner corner presser that presses the other inner corner of the pair of inner corners; and a mover that moves the rotary tool and the inner corner presser along a direction in which the butted portion extends. The inner corner presser includes a pressing roller that presses the other inner corner while rolling in a state where the inner corner presser is being moved by the mover.
According to the above configuration, the rotary tool is plunged into one of the inner corners of the butted portion where the first workpiece and the second workpiece are butted together, and the rotary tool is moved along the butted portion to perform friction stir welding on the butted portion. At the time, the pressing roller presses the other inner corner while rolling. Consequently, adhesion, to the pressing roller, of part of the workpieces softened due to the friction stir welding is effectively suppressed or avoided, which makes it possible to effectively avoid deformations or the like at the inner corners.
In addition, according to the above configuration, one of the pair of inner corners is friction-stir-welded by one rotary tool, and the other inner corner is pressed by the pressing roller. Thus, it is not necessary to use two rotary tools in a manner to face them each other, or to use a large-sized very heavy fixed-type pressing parts. This makes it possible to effectively suppress, for example, an increase in the configuration complexity of the apparatus, an increase in the size of the apparatus, or an increase in cost.
In order to solve the above-described problems, a friction stir welding method according to the present disclosure is a friction stir welding method for use in friction stir welding performed on a butted portion where a second workpiece is butted against a first workpiece such that the second workpiece is upright on the first workpiece. The friction stir welding method includes: plunging a rotary tool into one inner corner of a pair of inner corners that are positioned, at the butted portion, on both sides of the second workpiece, respectively, and moving the rotary tool along a direction in which the butted portion extends; and moving the rotary tool and an inner corner presser along the direction in which the butted portion extends, while pressing the other inner corner of the pair of inner corners by the inner corner presser. Pressing the other inner corner by the inner corner presser includes using a pressing roller as a pressing parts of the inner corner presser, the pressing parts pressing the other inner corner. The pressing roller presses the other inner corner while rolling in a state where the inner corner presser is being moved.
The above and other objectives, features, and advantages of the present disclosure will more fully be apparent from the following detailed description of preferred embodiments with accompanying drawings.
The present disclosure configured as described above has an advantage of providing a friction stir welding apparatus and a friction stir welding method that make it possible to, when performing friction stir welding on a butted portion where workpieces are butted together, effectively avoid deformations or the like at inner corners of the butted portion and suppress, for example, an increase in the configuration complexity of the apparatus, an increase in the size of the apparatus, or an increase in cost.
Hereinafter, representative embodiments of the present disclosure are described with reference to the drawings. In the drawings, the same or corresponding elements are denoted by the same reference signs, and repeating the same descriptions is avoided below.
First, one representative example of the configuration of a friction stir welding apparatus according to the present disclosure is specifically described with reference to
[Configuration of Friction Stir Welding Apparatus]
As shown in
As shown in
In the present disclosure, for example, the second workpiece 32 is upright on the front surface of the first workpiece 31, which is disposed horizontally. The butted portion 33, at which these workpieces 31 and 32 are butted together, is subjected to friction stir welding by the rotary tool 11. At the butted portion 33, inner corners 33a and 33b are positioned on both sides of the second workpiece 32, respectively. The rotary tool 11 is plunged into one of the pair of inner corners 33a and 33b to perform friction stir welding thereon. The inner corner presser 20 presses the other one of the pair of inner corners 33a and 33b, i.e., the inner corner that is not being friction-stirred by the rotary tool 11.
Hereinafter, for the sake of convenience of the description, one inner corner 33a shown on the right side in
As shown in
In the example shown in
As described below, the rotary tool 11 friction-stirs the first inner corner 33a while moving along the direction in which the first inner corner 33a extends. At the time, of the second inner corner 33b, which is positioned on the opposite side of the second workpiece 32 from the first inner corner 33a, a portion corresponding to, i.e., opposite to, the currently friction-stirred portion of the first inner corner 33a (hereinafter, “opposite portion”) is also softened due to the friction stirring. Here, the opposite portion or the vicinity thereof is pressed by the inner corner presser 20. At the first inner corner 33a, a portion that surrounds the currently friction-stirred portion into which the rotary tool 11 is being plunged (hereinafter, “surrounding portion”) is also softened. The surrounding portion is pressed by the stationary shoulder 12.
In Embodiment 1, the rotary tool 11 and the inner corner presser 20 are fixed to, for example, the frame 14. The frame 14 is moved by the frame mover 15 in the direction in which the butted portion 33 extends. In
Accordingly, the rotary tool 11 performs friction stir welding on the first inner corner 33a while moving in the direction in which the first inner corner 33a extends. Also, the inner corner presser 20 presses the second inner corner 33b while moving in the direction in which the second inner corner 33b extends. In a case where the rotary tool 11 performs friction stir welding on the second inner corner 33b while moving in the direction in which the second inner corner 33b extends, the inner corner presser 20 presses the first inner corner 33a while moving in the direction in which the first inner corner 33a extends.
In a case where the surface of the first workpiece 31 against which the second workpiece 32 is butted is defined as “front surface” and the opposite surface of the first workpiece 31 is defined as “back surface,” the backing 16 supports the back surface of the first workpiece 31 between the workpieces 31 and 32. As described below, in some cases, the front surface of the first workpiece 31 is referred to as “reference surface” for the sake of convenience of the description. The controller 17 controls the operations of the entire friction stir welding apparatus 10A including the rotary tool driver 13, the frame mover 15, etc.
A specific configuration of the friction stir welding apparatus 10A, i.e., specific configurations of the rotary tool 11, the stationary shoulder 12, the rotary tool driver 13, the frame 14, the frame mover 15, the backing 16, the controller 17, etc., are not particularly limited. Known configurations in the field of friction stir welding are suitably applicable.
Specific configurations of the workpieces 31 and 32 are also not particularly limited. In the example shown in
The material of each of the workpieces 31 and 32 is not particularly limited. Typically, each of the workpieces 31 and 32 may be made of a known metal material. The metal is not particularly limited a specific kind, but may be aluminum, copper, titanium, magnesium, or an alloy of any of these metals. Each of the workpieces 31 and 32 may be made of not a metal material, but any other known material that can be friction-stir-welded.
As previously described, the inner corner presser 20 presses one of the pair of inner corners 33a and 33b that is not friction-stirred (in the example shown in
A specific configuration of the pressing roller 21 is not particularly limited, so long as at least the pressing roller 21 can, while rolling, press, with its outer circumferential surface, the inner corner that is not friction-stirred. In the present embodiment, as shown in
For the sake of convenience of the description, one of the inclined surfaces 21b and 21c is defined as a first inclined surface 21b, and the other is defined as a second inclined surface 21c. As shown in
As shown in
Therefore, the inclination angle of each of the pair of inclined surfaces 21b and 21c may be set such that the inclined surface 21b and the inclined surface 21c come into contact with the reference surface 31a and the second upright surface 32b (or the first upright surface 32a) connected to the reference surface 31a, respectively. As one representative example, the second workpiece 32 is upright on and perpendicular to the reference surface 31a of the first workpiece 31. In this case, the inclination angle of each of the inclined surfaces 21b and 21c may be 45° with reference to the width direction of the pressing roller 21. Accordingly, an angle formed by the first inclined surface 21b and the second inclined surface 21c is 90°.
As described above, preferably, the outer circumferential portion of the pressing roller 21 of the present embodiment has a protruding three-dimensional shape corresponding to the recessed three-dimensional shape of the inner corner 33b. However, a specific shape of the pressing roller 21 is not limited to this example, so long as the pressing roller 21 has such a shape that the pressing roller 21 can press the inner corner that is not friction-stirred as described above. To be more specific, for example, the inclined surfaces 21b and 21c need not be formed, so long as the pressing roller 21 has such a shape that in a state where the pressing roller 21 is in contact with the second inner corner 33b (or the first inner corner 33a), the tread 21a is in contact with the fillet 34.
Preferably, the inclination angle of each of the inclined surfaces 21b and 21c is set to such an angle that, as previously described, in a state where the tread 21a is in contact with the fillet 34, the inclined surface 21b and the inclined surface 21c are in contact with the reference surface 31a and the second upright surface 32b (or the first upright surface 32a), respectively. However, this is merely a non-limiting example. For example, the inclination angle of each of the inclined surfaces 21b and 21c may be set such that in a state where the tread 21a is in contact with the fillet 34, only one of the surfaces (only the reference surface 31a, or only the second upright surface 32b or the first upright surface 32a) is contacted by one of the inclined surfaces. Alternatively, the inclination angle of each of the inclined surfaces 21b and 21c may be set such that the angle formed by the inclined surfaces 21b and 21c is slightly less than the angle formed by the reference surface 31a and the second upright surface 32b (or the first upright surface 32a).
In the example shown in
In the present embodiment, similar to the outer circumferential portion of the pressing roller 21, the shape of the stationary shoulder 12 may have inclined surfaces that come into contact with, at the first inner corner 33a, the reference surface 31a and the first upright surface 32a of the second workpiece 32. For example, in
As shown in
As shown in the drawing on the left side of
However, the pressing position of the pressing roller 21 need not coincide with the plunging position of the rotary tool 11. For example, as shown in the drawing on the right side of
The pressing roller 21 presses the material that has been softened due to the friction stirring by the rotary tool 11. Therefore, the softening of the material is less likely to occur at the forward side in the moving direction M although it depends on various conditions. In this respect, since the softened material is not immediately solidified, it is considered that the softened state of the material continues for a short period of time at the backward side in the moving direction M. Therefore, even though the pressing roller 21 performs the pressing at a position that is deviated backward in the moving direction M, the pressing can still be performed properly while suppressing deformations such as galling.
As shown in
In each of
The range of deviation of the pressing position from the plunging position is not particularly limited, but may be suitably set in accordance with specific configurations of the workpieces 31 and 32 forming the butted portion 33, the rotary tool 11, the stationary shoulder 12, and the pressing roller 21 as well as various conditions thereof such as moving speeds or pressing forces. As one representative example, the backward deviation Dr in
[Friction Stir Welding Method]
Next, one representative example of a friction stir welding method according to the present disclosure using the friction stir welding apparatus 10A configured as described above is specifically described with reference to
As shown in
In the example shown in
Next, as shown in
Thereafter, the rotary tool 11 is, while rotating, plunged into the first inner corner 33a, and as a result, the material of the first inner corner 33a and the material of the vicinity thereof are friction-stir-welded. At the time, at the first inner corner 33a, the stationary shoulder 12 is in contact with the reference surface 31a of the first workpiece 31 and the first upright surface 32a of the second workpiece 32, the reference surface 31a and the first upright surface 32a forming the first inner corner 33a. Therefore, the material softened at the first inner corner 33a is supported by the stationary shoulder 12. Accordingly, at the first inner corner 33a, the second workpiece 32 is joined to the first workpiece 31 in a state where the shape of the fillet 34 is maintained.
In a state where the first inner corner 33a is being friction-stirred, although the second inner corner 33b is not being friction-stirred, the material of the second inner corner 33b may become softened. Therefore, in a case where a conventional movable presser that is pressing the second inner corner 33b is moved in the direction in which the second inner corner 33b extends, the softened material tends to adhere to the pressing surface of the conventional presser. Consequently, deformations such as galling, tears, burrs, etc., occur at the second inner corner 33b.
In this respect, in the present disclosure, as previously described, the pressing roller 21 included in the inner corner presser 20 is in contact with (i.e., presses) the second inner corner 33b. Accordingly, the pressing roller 21 presses the second inner corner 33b while rolling. Therefore, even though the material in the vicinity of the second inner corner 33b is softened, adhesion of the material to, for example, the tread 21a of the pressing roller 21 is effectively suppressed or avoided. Consequently, the occurrence of deformations such as galling on the surface of the second inner corner 33b is also effectively suppressed or avoided, and thereby the shape of the fillet 34 is maintained.
Thereafter, in a state where the friction stir welding on the entire first inner corner 33a is completed, as shown in
Next, as shown in
In a state where the second inner corner 33b is being friction-stirred, the material of the previously joined first inner corner 33a may become softened again. The pressing roller 21 included in the inner corner presser 20 presses the first inner corner 33a while rolling. Therefore, even though the material in the vicinity of the first inner corner 33a is softened, adhesion of the material to, for example, the tread 21a of the pressing roller 21 is effectively suppressed or avoided. Consequently, the occurrence of deformations such as galling on the surface of the first inner corner 33a is also effectively suppressed or avoided.
As a result, as shown in
In a case where a side edge of the second workpiece 32, the side edge being butted against the first workpiece 31, does not include the pre-formed fillet 34, for example, a linear object may be used, with which to supplement a material that corresponds to the fillet 34. The linear object corresponds to the aforementioned material corresponding to the volume of the space, the material being added externally. A specific configuration of the linear object is not particularly limited, so long as the linear object is made of the same material as, or a similar material to, the material of the workpieces 31 and 32 (or made of a material that can be friction-stirred with the workpieces 31 and 32) and the linear object is in such a shape that can be disposed at each of the inner corners 33a and 33b along the direction in which the butted portion 33 extends.
For example, as shown in
Alternatively, as shown in
In a case where the second workpiece 32 and the first workpiece 31 are friction-stirred together with the linear object 42, at the first inner corner 33a, not only are the second workpiece 32 and the first workpiece 31 joined together by the friction stirring, but the fillet 34 is also formed. The material that has been softened by the friction stirring flows toward the second inner corner 33b due to a plastic flow. At the time, since a space corresponding to the fillet 34 is present between the second inner corner 33b and the pressing roller 21, the fillet 34 is formed also at the second inner corner 33b.
In a state where the entire joining at the first inner corner 33a is completed, the fillet 34 has been formed at the second inner corner 33b, but the second workpiece 32 and the first workpiece 31 are not yet joined together at the second inner corner 33b. Therefore, as previously described, the position of the rotary tool 11 and the position of the inner corner presser 20 may be switched with each other, and the second inner corner 33b may be friction-stirred by the rotary tool 11. Consequently, also at the second inner corner 33b, the second workpiece 32 and the first workpiece 31 are joined together, and the occurrence of deformations, such as galling, on the surface of the fillet 34 is suppressed. In this manner, a high-quality T-shaped construction 30 is manufactured.
A specific cross-sectional shape of the linear object is not limited to, for example, a triangular or circular shape. For example, as shown in
The technique shown in
[Variations]
In the friction stir welding apparatus 10A according to Embodiment 1, as shown in
In the inner corner presser 20, the roller support 22, which supports the pressing roller 21 such that the pressing roller 21 is rollable, may support the pressing roller 21 such that the pressing roller 21 is movable with play in the direction of the rolling axis of the pressing roller 21. Specifically, for example, as shown in
On the other hand, in a case where the length of the roller support shaft 22a is greater than the thickness of the pressing roller 21 as shown in
In a case where the pressing roller 21 is supported in the inner corner presser 20 such that the pressing roller 21 is movable with play so as to be shiftable in the direction in which the roller support shaft 22a extends (i.e., in the direction of the rolling axis), when the pressing roller 21 is brought into contact with either the inner corner 33a or the inner corner 33b, the tread 21a of the pressing roller 21 can be readily positioned on the surface of the fillet 34, or the position of the tread 21a can be readily aligned with the position at which the space corresponding to the fillet 34 is present. This make it possible to precisely form the shape of the fillet 34, and thereby the quality of the T-shaped construction 30 can be improved.
In the example shown in
Fields to which the friction stir welding apparatus 10A according to Embodiment 1 or the friction stir welding method according to Embodiment 1 is applied are not particularly limited. The friction stir welding apparatus 10A and the friction stir welding method according to Embodiment 1 are suitably and widely applicable to the manufacturing of a component including a T-shaped structure (T joint). In particular, the friction stir welding apparatus and the friction stir welding method according to the present disclosure are suitably applicable to various aircraft components, for example, a structural component that is used in the manufacturing of an aircraft fuselage and that includes a T-shaped structure (T-joint).
For example, assume a case where in a skin/stringer structure that is used in, for example, an aircraft fuselage or aircraft blade, the stringer is upright on the skin (i.e., T-shaped structure), and inner corners formed by the skin and the stringer are coupled by friction stir welding. Here, it is conceivable to use a fixed-type pressing parts that presses the entire inner corner along the butted portion. In this case, however, the pressing parts would be elongated (i.e., increased in size) to have a length of greater than 10 m, and also, the weight of the pressing parts would be increased so as to achieve sufficient pressing force. In addition, such a fixed-type pressing parts needs to be properly fixed at its both ends to prevent positional deviation of the pressing parts.
In a case where a conventional movable pressing parts is used in order to avoid such increase in the length and the weight of the pressing parts, part of the softened material tends to adhere to the pressing surface of the pressing parts as previously described. Consequently, deformations, such as galling, occur on the surface of the inner corners. It is highly likely that deformations (flaws), such as galling, are not tolerated in various aircraft components. Even if they are tolerated, it is desirable that the deformations (flaws) be minimized.
According to the present disclosure, the inner corner that is not being friction-stirred is pressed by the pressing roller. Consequently, adhesion, to the pressing roller, of part of the workpieces softened due to the friction stirring is effectively suppressed or avoided, which makes it possible to effectively avoid the occurrence of deformations (flaws) or the like at the inner corners.
In addition, according to the present disclosure, one of the pair of inner corners is friction-stir-welded by one rotary tool, and the other inner corner is pressed by the pressing roller. Thus, unlike the friction stir welding apparatus disclosed in Patent Literature 1, it is not necessary to use two rotary tools in a manner to face them each other, or to use a large-sized very heavy fixed-type pressing parts. This makes it possible to effectively suppress, for example, an increase in the configuration complexity of the apparatus, an increase in the size of the apparatus, or an increase in cost.
As shown in
For example, as shown in
As described above, the friction stir welding apparatus according to the present disclosure may include movers that move the rotary tool 11 and the inner corner presser 20, respectively, in the direction in which the butted portion 33 extends. A specific configuration of the movers is not particularly limited. One example configuration may include a tool mounter, such as the frame 14, to which the rotary tool 11 and the inner corner presser 20 are mounted, and the tool mounter may be moved in the direction in which the butted portion 33 extends, as in Embodiment 1. Another example configuration may include the rotary tool mover 18, which moves the rotary tool 11, and the inner corner presser mover 23, which moves the inner corner presser 20, as in Embodiment 2.
Similar to the frame mover 15, each of the rotary tool mover 18 and the inner corner presser mover 23 may be controlled by the controller 17. The rotary tool mover 18 and the inner corner presser mover 23 may move the rotary tool 11 and the inner corner presser 20 independently. The rotary tool mover 18 and the inner corner presser mover 23 may move the rotary tool 11 and the inner corner presser 20 in synchronization with each other.
Each of the friction stir welding apparatus 10A according to Embodiment 1 and the friction stir welding apparatus 10B according to Embodiment 2 includes one rotary tool 11 and one inner corner presser 20, which face each other. On the other hand, a friction stir welding apparatus according to Embodiment 3 includes two sets of the rotary tool and the inner corner presser. In each set, the rotary tool and the inner corner presser face each other.
In a friction stir welding apparatus 10C shown in
Thus, at the first inner corner 33a of the second workpiece 32, the first rotary tool 11A is positioned at the forward side in the moving direction M, and the second pressing roller 21B is positioned rearward of the first rotary tool 11A. At the second inner corner 33b of the second workpiece 32, the first pressing roller 21A is positioned at the forward side in the moving direction M, and the second rotary tool 11B is positioned rearward of the first pressing roller 21A.
For the sake of convenience of illustration, for the inner corner pressers 20,
The set of the first rotary tool 11A and the first pressing roller 21A (a first inner corner presser) is defined as a first tool set of the friction stir welding apparatus 10C, and the set of the second rotary tool 11B and the second pressing roller 21B (a second inner corner presser) is defined as a second tool set of the friction stir welding apparatus 10C. In this case, the first tool set is positioned at the forward side in the moving direction M, and the second tool set is positioned at the backward side in the moving direction M. Between these tool sets, the positions of the rotary tools 11A and 11B are staggered, and the positions of the pressing rollers 21A and 21B are staggered.
In each of the above-described friction stir welding apparatuses 10A and 10B, the number of tool sets including the rotary tool 11 and the pressing roller 21 (the inner corner presser 20) is one. Therefore, in a friction stir welding method using the friction stir welding apparatus 10A or 10B, as shown in
On the other hand, as described above, the friction stir welding apparatus 10C according to Embodiment 3 includes the two tool sets, and between these two tool sets, the positions of the rotary tools 11 are staggered, and the positions of the pressing rollers 21 are staggered. Therefore, both the inner corners 33a and 33b can be friction-stir-welded by the rotary tools 11A and 11B concurrently by moving the rotary tools 11A and 11B in the moving direction M. Consequently, by moving these tool sets once, the friction stir welding can be performed on the entire butted portion 33.
The pressing rollers 21A and 21B (the inner corner pressers) are arranged such that the pressing rollers 21A and 21B face the rotary tools 11A and 11B, respectively. That is, each of the pressing rollers 21A and 21B presses the inner corner that is not friction-stirred. Consequently, adhesion, to the pressing rollers 21A and 21B, of part of the material softened due to the friction stirring can be effectively suppressed or avoided, which makes it possible to effectively avoid the occurrence of deformations (flaws), such as galling, at the inner corners.
In the friction stir welding apparatus 10C of
Also for the friction stir welding apparatus 10C according to Embodiment 3, in a case where a space corresponding to the fillet 34 is present between the tread of each of the pressing rollers 21A and 21B and a corresponding one of the inner corners 33a and 33b, the above-described linear object 42 may be disposed on each of the inner corners 33a and 33b as shown in
[Friction Stir Welding Apparatus and Friction Stir Welding Method According to Present Disclosure]
A friction stir welding apparatus according to the present disclosure is a friction stir welding apparatus for use in friction stir welding performed on a butted portion where a second workpiece is butted against a first workpiece such that the second workpiece is upright on the first workpiece. The friction stir welding apparatus includes: a rotary tool that is plunged into one inner corner of a pair of inner corners that are positioned, at the butted portion, on both sides of the second workpiece, respectively; an inner corner presser that presses the other inner corner of the pair of inner corners; and a mover that moves the rotary tool and the inner corner presser along a direction in which the butted portion extends. The inner corner presser includes a pressing roller that presses the other inner corner while rolling in a state where the inner corner presser is being moved by the mover.
According to the above configuration, the rotary tool is plunged into one of the inner corners of the butted portion where the first workpiece and the second workpiece are butted together, and the rotary tool is moved along the butted portion to perform friction stir welding on the butted portion. At the time, the pressing roller presses the other inner corner while rolling. Consequently, adhesion, to the pressing roller, of part of the workpieces softened due to the friction stir welding is effectively suppressed or avoided, which makes it possible to effectively avoid deformations or the like at the inner corners.
In addition, according to the above configuration, one of the pair of inner corners is friction-stir-welded by one rotary tool, and the other inner corner is pressed by the pressing roller. Thus, it is not necessary to use two rotary tools in a manner to face them each other, or to use a large-sized very heavy fixed-type pressing parts. This makes it possible to effectively suppress, for example, an increase in the configuration complexity of the apparatus, an increase in the size of the apparatus, or an increase in cost.
The friction stir welding apparatus configured as described above may further include a stationary shoulder that is positioned at an outer periphery of the rotary tool, the stationary shoulder coming into contact with the one inner corner in a state where the rotary tool is plunged into the one inner corner.
In the friction stir welding apparatus with the above-described configuration, an outer circumferential surface of the pressing roller of the inner corner presser may be a tread that presses the other inner corner. In a state where the pressing roller is in contact with the other inner corner, the tread may be in contact with a fillet that is formed by joining the first workpiece and the second workpiece together, or a space corresponding to the fillet may be present between the tread and the other inner corner.
In the friction stir welding apparatus with the above-described configuration, the pressing roller may include a pair of inclined surfaces on both sides of the tread, and each of the inclined surfaces may extend from the tread toward an inner circumferential side of the pressing roller. At the butted portion, a front surface of the first workpiece may be a reference surface, and both surfaces of the upright second workpiece may be upright surfaces, each of which is upright on the reference surface. An inclination angle of each inclined surface may be set such that, in the state where the pressing roller is in contact with the other inner corner, the inclined surfaces are in contact with the reference surface and one of the upright surfaces, respectively.
In the friction stir welding apparatus with the above-described configuration, the inner corner presser may include a roller support that supports the pressing roller such that the pressing roller is rollable, and the roller support may support the pressing roller such that the pressing roller is movable with play in a direction of a rolling axis of the pressing roller.
In the friction stir welding apparatus with the above-described configuration, a pressing position of the pressing roller may be located at an opposite side of the second workpiece from a plunging position of the rotary tool, or the pressing position of the pressing roller may be, as seen from the plunging position of the rotary tool, deviated backward in a moving direction of the mover.
A friction stir welding method according to the present disclosure is a friction stir welding method for use in friction stir welding performed on a butted portion where a second workpiece is butted against a first workpiece such that the second workpiece is upright on the first workpiece. The friction stir welding method includes: plunging a rotary tool into one inner corner of a pair of inner corners that are positioned, at the butted portion, on both sides of the second workpiece, respectively, and moving the rotary tool along a direction in which the butted portion extends; and moving the rotary tool and an inner corner presser along the direction in which the butted portion extends, while pressing the other inner corner of the pair of inner corners by the inner corner presser. Pressing the other inner corner by the inner corner presser includes using a pressing roller as a pressing parts of the inner corner presser, the pressing parts pressing the other inner corner. The pressing roller presses the other inner corner while rolling in a state where the inner corner presser is being moved.
In the above-described friction stir welding method, a linear object may be disposed at least between the rotary tool and one of the inner corners, such that the linear object extends along the direction in which the butted portion extends. The friction stir welding method may comprise: softening the linear object by the rotary tool; and pushing, by the rotary tool, the softened linear object into the butted portion to form a fillet on the butted portion.
In the above-described friction stir welding method, a side edge of the second workpiece, the side edge being butted against the first workpiece, may include a pre-formed fillet.
The present disclosure is not limited to the embodiments described above, and various modifications can be made within the scope of the Claims. Embodiments obtained by suitably combining technical means that are disclosed in different embodiments and variations also fall within the technical scope of the present disclosure.
From the foregoing description, numerous modifications and other embodiments of the present disclosure are obvious to a person skilled in the art. Therefore, the foregoing description should be interpreted only as an example and is provided for the purpose of teaching the best mode for carrying out the present disclosure to a person skilled in the art. The structural and/or functional details may be substantially modified without departing from the spirit of the present disclosure.
The present disclosure is widely and suitably applicable to the field of manufacturing a construction including a T-shaped structure (T-joint). In particular, the present disclosure is suitably applicable to the field of manufacturing various aircraft components each including a T-shaped structure.
| Number | Date | Country | Kind |
|---|---|---|---|
| 2019-030173 | Feb 2019 | JP | national |
| Filing Document | Filing Date | Country | Kind |
|---|---|---|---|
| PCT/JP2020/007050 | 2/21/2020 | WO | 00 |
