JP5148169B2 - Friction stir tool - Google Patents

Description

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

  FIG. 14 shows an example of a conventional friction stir tool. The friction stir tool 100 has a shoulder portion 102 at the front end of the main body 101 and a stirring pin 103 protruding from the center thereof, and the axis C of the main body 101 is in the traveling direction. The shoulder portion 102 is brought into contact with the surface 105 of the bonding material 104 and held and rotated so as to form an opposite angle θ, and the stirring pin 103 is inserted into the bonding material 104 in the traveling direction A. It is designed to move. The opposite angle is important for stabilizing the joint strength because the fluidized material is wound below the shoulder portion 102 to make the thickness of the stirring layer constant in the joint portion.

  However, when the friction stir tool 100 is folded or moved along a path having a free curve shape, the opposite angle must be formed in the folding direction by reversing the inclination of the axis C in the main body 101, etc. However, a support device that can freely change the support angle of the main body 101 in accordance with the traveling direction becomes extremely expensive.

In view of this, there is a structure in which a protruding portion having a spiral shape or the like is provided around the stirring pin so that the fluidizing material is fed into the central portion without tilting the main body 101 (see Patent Document 1).
In addition, in this application, the surface of a shoulder part and the height of the protruding item | line part (chip | tip) mentioned later shall mean the height which protrudes toward the bonding material surface.
Japanese Patent No. 3409971

By the way, since the shoulder part 102 and the stirring pin 103 are easily worn, it is necessary to replace the entire stirring tool in a short period of time. However, since the stirring tool uses a relatively expensive material, if the number of replacements increases, the running cost increases accordingly. Therefore, it is desired to reduce the running cost in consideration of replacement. In addition, if the shoulder portion 102 and the stirring pin 103 are made in a complicated shape, the number of processing steps increases and the cost becomes high, wear and breakage easily occur, and durability deteriorates.
Therefore, the present application aims to realize such various requests.

In order to solve the above-mentioned problem, the invention of claim 1 relating to a friction stir tool is provided with a friction stirrer in which a shoulder portion that comes into contact with the surface of the joining material and a stirring pin that is inserted into the joining material are provided on the front end side of the rod-like body portion In the tool,
Tip projecting so as to enter into the bonding material, a plurality set on the shoulder portion surrounds the stirring pins,
At least the so as to be replaceable each chip, Rutotomoni provided in the shoulder portion and the separate,
Each of the chips is integrated by being fitted into a mounting hole provided in the shoulder portion .

  According to a second aspect of the present invention, in the first aspect, each of the tips has a long ridge in the rotational direction when the shoulder portion is viewed from the rotational axis direction. The height in the circumferential direction changes so that the rear end side becomes higher.

  The invention of claim 3 is characterized in that, in the above-mentioned claim 2, the gap between the front end portion in the rotation direction of each chip and the stirring pin is made larger than the gap between the rear end portion side in the rotation direction and the stirring pin. .

According to a fourth aspect of the present invention , in any one of the first to third aspects, the stirring pin is provided separately from the shoulder portion .

According to claim 1, since the tip protruding so as to enter into the bonding material is provided in the shoulder portion surrounding the stirring pin, and at least the tip can be replaced, it is provided separately from the main body portion. When the tip is worn or damaged by stirring the joining material, only a relatively small tip or a part including the tip can be replaced. Compared to the case where the entire main body is replaced due to the tip breakage or the like. It is economical and can reduce running costs. In addition, machining is facilitated by making the chip that requires machining separate from the main body side.
In addition, since each chip is fitted and integrated into a mounting hole provided in the shoulder portion, it is possible to replace each chip and minimize the replacement portion, thereby further improving cost performance.

  According to claim 2, each tip has a long ridge in the rotational direction when the shoulder portion is viewed from the rotational axis direction, such that the front end side in the rotational direction of the tip is low and the rear end side in the rotational direction is high. Since the height in the circumferential direction has been changed, even if the main body is upright, it can be in a state that is substantially the same as if it had always formed an opposite corner, and fluidized toward the rear end in the rotational direction as it rotates. A large amount of material can be fed and can rotate smoothly.

  According to the third aspect, since the gap between the front end portion in the rotation direction of each chip and the stirring pin is made larger than the gap between the rear end portion side in the rotation direction and the stirring pin, the fluidized material is collected inside the chip in the rotation direction. It is easy to accumulate and can be made to be in a state substantially the same as the case where the opposite corner is formed at all times.

According to the fourth aspect , the stirrer pin, which is troublesome and easily damaged, is created separately and is detachably attached to the shoulder portion so that it can be replaced. Therefore, it is possible to replace the stirrer pin alone. The cost can be improved by minimizing the exchange part. In addition, it becomes easy to change the material, such as changing the material of the stirring pin to carbide or the like rather than other parts, depending on the material to be frictionally stirred.

1 to 6 relate to a first reference example , FIG. 1 is a view showing an appearance of the friction stir tool 1 on the stirring head side, FIG. 2 is an axial sectional view, and FIG. 3 is an exploded sectional view. In these drawings, the friction stir tool 1 has a main body portion 2 having a round bar shape, and a separate stirrer head 3 which is detachably provided at the tip thereof. The main body 2 is made of a rigid member such as a general steel material, and is provided with a mounting hole 4 opened downward in the figure at the center. The mounting hole 4 is formed by carving in the axial direction from the end face of the main body 2 to which the stirring head 3 is attached.

  The agitation head 3 is formed by sintering or electric discharge machining using a super-hard material. One surface is a shoulder portion 5 and the other surface is a mounting surface 6. An agitation pin 7 protruding in the axial direction is provided at the center of the shoulder portion 5. An agitation pin 7 and an attachment shaft 8 projecting to the opposite side in the axial direction are integrally provided at the center of the attachment surface 6. An anti-rotation projection 10 is integrally formed on the mounting surface 6. The mounting shaft 8 is fitted and integrated into the mounting hole 4 of the main body 2 by press-fitting or the like, and the anti-rotation convex portion 10 is to a positioning concave portion 11 formed by carving the end surface of the main body portion 2 in contact with the mounting surface 6 in the axial direction. The agitating head 3 and the main body 2 are positioned by the fitting and the rotation is prevented during rotation. If the mounting shaft 8 has a square shape and the mounting hole 4 has a corresponding square hole, the detent protrusion 10 and the positioning recess 11 can be omitted.

  A screw 12 is formed on the stirring pin 7. The screw 12 feeds the fluidizing material to the bonding material side during stirring. The surface of the shoulder portion 5 is a substantially angled inclined surface so that the central portion is low and the outer peripheral portion is high in the radial cross section, and the fluidized material is accumulated in the central portion to prevent burrs during friction stir welding. It is like that. From the surface of the shoulder portion 5, a tip 13 forming a ridge is formed to protrude.

  FIG. 4 is a view (a view in the direction of arrow D in FIG. 1) shown from the lower side in the axial direction of the shoulder portion 5, and FIG. 5 is a side view of the chip 13, which is shown upside down. In these drawings, the tip 13 is a pair of arcuate portions arranged symmetrically with the stirring pin 7 interposed therebetween, and each of the tips 13 has an arcuate shape that curves convexly outward in the radial direction and is on a concentric circle E with respect to the center O. And each of them is inclined with respect to the concentric circle E, and when the rotation direction of the agitation head 3 is B, the rotation direction front end portion 14 is opened so as to be positioned on the outer peripheral side with respect to the rotation direction rear end portion 15. The rotation direction front end portion 14 side is farther from the stirring pin 7, and the rotation direction rear end portion 15 side is closer to the stirring pin 7.

  As a result, the gap 16 between the rotation direction front end portion 14 and the stirring pin 7 is wider than the gap 17 between the rotation direction rear end portion 15 and the stirring pin 7, and if the dimensions of the gaps 16 and 17 are a and b, There is a relationship of a> b, and in the rotation direction B, wide gaps 16 and narrow gaps 17 are alternately arranged. The concentric circle E is illustrated as passing through the inner peripheral portion of the rear end portion 15 in the rotational direction.

Each chip 13 is not continuous with each other and is independent, and a separation portion is formed between the rotation direction front end portion 14 and the rotation direction rear end portion 15 of the adjacent chips 13.
Furthermore, if the distance between the front end 14 in the rotational direction and the outer periphery of the stirring head 3 (shoulder part 5) is c and the distance at the rear end 15 in the rotational direction is d, c <d between these intervals. There is a relationship, and a radial difference (dc) is formed between the rotation direction front end portion 14 and the rotation direction rear end portion 15.

  The wide gap 16 allows a large amount of fluidized material to be wound inside the chip 13. The arcuate tip 13 makes it smooth that the entrained fluidizing material moves toward the narrow gap 17. The narrow gap 17 restricts the outflow of the fluidizing material wound inside the chip 13 to maintain a certain amount of accumulation, and the excess amount overflows from the narrow gap 17 and another chip 13 located immediately after the gap 13 flows out. The large gap 16 in FIG. 3 is again wound inside another chip 13.

  As shown in FIG. 5, the tip 13 is inclined so that the height of the tip 13 gradually increases in the rotational direction so that the front end portion 14 in the rotational direction is the lowest and the rear end portion 15 in the rotational direction is the highest. A slope is formed, and this inclination angle forms an opposite angle θ. In this way, by forming the inclined surface in the rotation direction, it is possible to always maintain the facing angle θ with respect to the traveling direction. Therefore, even if the main body 2 is kept upright and held at a constant holding angle, it can be moved in a free direction on the surface of the bonding material.

  FIG. 6 is a view showing a joining operation state using the friction stir tool 1. When the joining materials 20 and 21 are abutted, the stirring pin 7 rotated along the abutting portion 22 is inserted, and the shoulder portion 5 is brought into sliding contact with the surfaces 20a and 21a of the joining materials 20 and 21, the friction agitation is performed. The bonding materials 20 and 21 on both sides of the material 22 are melted and stirred to form a stirring mixed layer 23, and the bonding materials 20 and 21 are joined and integrated by the stirring mixed layer 23.

The number and shape of the chips 13 are arbitrary. For example, as shown in the second reference example of FIG. 7, a flat plate shape may be provided, and three linear chips 13 may be provided in the illustrated state. Further, as shown in the third reference example of FIG. 8, the four chips 13 may be provided in a substantially quadrilateral shape around the stirring pin 7. Further, such a linear chip 13 is easy to manufacture as long as the shape is simple. The number of these chips 13 can be more than the 2 to 4 already shown. Also, the number of arcuate chips 13 shown in FIG. 4 can be three or more.

  In this way, the main body 2 and the shoulder 5, which is susceptible to wear, and the stirring head 3 formed with the stirring pin 7 and the tip 13 are separated, so that only the stirring head 3 is removed from the main body 2 when worn. Can be replaced. For this reason, since the large-sized main-body part 2 can be used in common, it is economical. In addition, by providing the stirring head 3 with the agitation pin 7 and the chip 13 that require machining or the like, the agitation head 3 can be easily formed because only the agitation head 3 of a small part needs to be processed. Moreover, only the stirring head 3 can be freely set to a desired level of high hardness.

  In addition, a plurality of tips 13 are provided, and each tip 13 is provided such that a wide gap 16 between the rotation direction front end portion 14 and the stirring pin 7 is wider than a narrow gap 17 between the rotation direction rear end portion 15 and the stirring pin 7. Therefore, the fluidizing material can be reliably collected inside the chip 13, and the generation of burrs can be prevented and the friction stir can be made more efficient. Moreover, it is possible to form a substantially opposite corner. Further, since the height of the tip 13 is changed in the rotation direction so that the front end portion 14 in the rotation direction is lowered, this also makes it possible to form a substantially opposite angle, and the travel path of the friction stir tool 1 is folded back or a free curve. The friction stir welding can be performed while always maintaining the facing angle θ.

  Further, if the tip 13 is formed in an arc shape, the flow of the entrained fluidizing material can be made smooth toward the stirring pin 7 on the center side, and if the tip 13 is formed in a flat plate shape, the processing of the tip 13 is facilitated. Furthermore, even if the fluidizing material overflows from one rotational direction rear end portion 15 by arranging the rotational direction front end portion 14 of the other chip 13 in the vicinity of the rotational direction rear end portion 15 of the one chip 13, Since it is accommodated inside the front end portion 14 in the rotational direction, the generation of burrs can be prevented.

9 to 11 are examples in which the rotation direction front end portion 14 is provided so as to reach the outer peripheral portion of the stirring head 3. FIG. 9 is a fourth reference example , A is a perspective view of the agitation head 3, and B is a diagram showing the state of A from above in the axial direction (the same applies to FIGS. 10 and 11 below). In this example, a pair of arcuate chips 13 and 13 are formed so as to protrude integrally with the surface of the shoulder portion 5 across the center and arranged slightly offset from each other in the radially opposite direction. It approximates to the first reference example in that the tip 13 forms two arcs. Each chip 13 includes a rotation direction front end portion 14 and a rotation direction rear end portion 15. The rotation direction front end portion 14 reaches the vicinity of the outer peripheral portion of the stirring head 3, and the rotation direction rear end portion 15 is the stirring head 7 on the center side. Located in the vicinity.

  Therefore, the front end portion 14 in the rotation direction opens in the rotation direction B with a large gap between the stirring pin 7 and the rear end portion 15 in the rotation direction is narrowed with a small gap between the stirring pin 7 and the central portion. For this reason, when the shoulder portion 5 rotates in the direction indicated by the arrow B, the fluidizing material can be taken into the chip 13 from the wide gap on the rotation direction front end portion 14 side and stored. Moreover, since the gap on the rear end portion 15 side in the rotation direction is narrowed, it can be adjusted so as to restrict the outflow of the fluidizing material, so that a lot of fluidizing material can be fed into the central portion to improve the joining quality.

FIG. 10 is a fifth reference example . In this example, a pair of chips 13 in FIG. 9 is equivalent to a structure in which one chip 13 is further added and a total of three chips 13 are arranged at intervals of 120 °. If it does in this way, since each chip | tip 13,13,13 can be shortened and reduced in size, it can make it hard to break. Note that the number of chips 13 is not limited as long as the number is two or more.

FIG. 11 shows a sixth reference example . In this example, three chips 13, 13, 13 having a flat plate shape similar to the second reference example are formed so as to project, but each of the shoulder portions 5 is arranged in the direction of the rotation axis. When viewed from (B), it forms a straight line. When the front end portion 14 in the rotational direction of each chip 13 faces the outer peripheral portion of the stirring head 3 and the rear end portion 15 in the rotational direction faces the vicinity of the stirring pin 7 on the center side, it approximates the second reference example of FIG. Become a thing.

FIG. 12 shows a first embodiment in which only the chip 13 is separated. A corresponds to FIG. 1, B corresponds to FIG. 2, and C corresponds to FIG. In these drawings, the main body 2 and the shoulder portion 5 are integrated, and a mounting hole 30 engraved in the axial direction is formed on the surface of the shoulder portion 5, and a chip 13 formed separately in advance is press-fitted therein. And integrated. The chip 13 can be suitably used in the shape shown in each of the first to sixth reference examples .

  In this way, when the chip 13 is damaged, it is sufficient to replace only the chip 13, so that it is possible to replace each chip 13, and the replacement portion can be minimized. Economical because of the lowest cost. Further, since the chip 13 can be processed separately from the main body 2, the processing is easy, and the mounting structure of the chip 13 in the main body 2 only forms the mounting hole 30, so that machining is minimized and the processing shape is also reduced. Become simple.

Note that the stirring pin 7 may be provided separately from the stirring head 3 so as to be detachable. FIG. 13 is a diagram showing this as a second embodiment , in which A is a reference example in which the stirring pin 7 is separated from the first reference example of FIG. 2, and B is the first example of FIG. It is 2nd Example applied with respect to the Example . First, in A, attachment holes 40 and 41 are provided along the rotation axis at the centers of the main body 2 and the agitation head 3, and the agitation pins 7 formed separately are fitted into the holes so as to be detachably attached. At this time, for example, the fitting portion 42 of the stirring pin 7 is formed in a square shaft shape, and the mounting holes 40 and 41 side are formed in a square hole shape corresponding thereto and integrated by press-fitting or the like. The agitation head 3 can be fixed to the main body 2 by the agitation pin 7. In addition to the agitation pin 7, it is detachably attached to the main body 2 by fitting or the like. In this case, the number of the rotation preventing projections 10 and the positioning recesses 11 may be plural as shown in the figure.

  In B, since the agitation head 3 is integral with the main body 2, a mounting hole 40 is formed from the agitation head 3 to the main body 2, and the same agitation pin 7 as in A is attached. The agitation pin 7 can be attached to the main body 2 side in various ways as shown in A and B. For example, the agitation pin 7 can be attached by a screw formed in a tightening direction by rotation.

As described above, since the processing is troublesome and the breakable stirring pin 7 can be replaced separately from the shoulder portion 5, the replacement portion can be minimized and the cost performance can be improved. In addition, it becomes easy to change the material, such as changing the material of the agitation pin 7 to carbide or the like rather than other parts, depending on the material to be frictionally agitated.

The figure which shows the stirring head side external appearance of the friction stirring tool which concerns on a 1st reference example Axial sectional view of the friction stir tool Exploded sectional view of the friction stir tool The figure which shows the stirring head of the said friction stirring tool from the axial direction downward direction Side view of the stirring head The figure which shows the joining operation state using the friction stir tool Similar to FIG. 4 according to the second reference example Same as above for the third reference example The figure which shows the stirring head part which concerns on a 4th reference example Same as above for the fifth reference example Same as above for the sixth reference example Sectional drawing of the site | part similar to FIGS. 1-3 which concerns on 1st Example Exploded sectional view according to the second embodiment The figure which shows the friction stir tool of the conventional example

Explanation of symbols

1: Friction stirring tool, 2: Main body part, 3: Stirring head, 4: Mounting hole, 5: Shoulder part, 7: Stirring pin, 13: Tip, 14: Front end part in the rotational direction, 15: Rear end part in the rotational direction, 16: wide gap, 17: narrow gap, 20: bonding material, 21: bonding material, 30: mounting hole, 40: mounting hole, 41: mounting hole, 42: fitting part

Claims (4)

In the friction stir tool provided on the front end side of the rod-shaped main body portion, a shoulder portion that comes into contact with the surface of the bonding material, and a stirring pin inserted into the bonding material,
Tip projecting so as to enter into the bonding material, a plurality set on the shoulder portion surrounds the stirring pins,
At least the so as to be replaceable each chip, Rutotomoni provided in the shoulder portion and the separate,
The friction stir tool, wherein each of the chips is fitted into a mounting hole provided in the shoulder portion and integrated . Each of the tips has a long protrusion in the rotational direction when the shoulder portion is viewed from the rotational axis direction, and the height in the circumferential direction is such that the front end side in the rotational direction of the tip is low and the rear end side in the rotational direction is high. The friction stir tool according to claim 1, wherein the friction stir tool changes. The friction stir tool according to claim 2, wherein a gap between the front end portion in the rotation direction of each tip and the stirring pin is made larger than a gap between the rear end portion side in the rotation direction and the stirring pin. The friction stirring tool according to claim 1, wherein the stirring pin is provided separately from the shoulder portion .

Images