TWI739681B - Friction stir welding holding fixture system - Google Patents

Abstract

A friction stir welding holding fixture system, which is suitable for a friction stir welding equipment. The friction stir welding equipment includes a spindle system. The spindle system includes a peripheral non-rotating area, a rotatable spindle axis and a mixing head connected to the spindle axis. The holding fixture system includes: a holding fixture adjacent to the non-rotating area and located beside the mixing head. The holding fixture has a base, a linear sliding mechanism connected to the base, a rebound mechanism arranged on the linear sliding mechanism and respectively connected to the base, and a contact part arranged at the end of the linear sliding mechanism. When the mixing head is not in contact with the workpiece to be joined, the first surface of the contact part protrudes from the second surface of the mixing head. During welding, the contact part will first press down on the surface of the workpiece to be joined, and then continue to press down and keep it tight Welding.

Description

Friction stir welding holding fixture system

The present invention is a friction stir welding holding fixture system, in particular, it relates to a holding fixture system which is arranged on the side of a stirring head and can continuously press down the workpiece and can automatically adjust the pressing stroke within a certain range. .

Friction stir welding is a new welding method developed by The Welding Institute (TWI) in 1991. Because friction stir welding has superior welding quality advantages over traditional welding, it has been widely used in aluminum alloy related products internationally. In recent years, the trend of energy saving and carbon reduction and environmental protection The promotion of related policies for electric vehicles, etc., has made the production and application of aluminum alloys and the demand for friction stir welding more extensive year by year.

Aluminum alloy friction stir welding has higher strength than traditional welding, but in the process of welding thin-plate workpieces, due to the insufficient deformation resistance of the welded itself, warping and wrinkle deformation are prone to occur around the stirring head, resulting in failure to obtain good results. The welding seam is deformed, which limits the application of friction stir welding on thin plate workpieces. For thin plate welding, the traditional clamps are all dedicated clamps. The clamps are designed for different joint forms and product methods, and then corresponding to a small number of diverse products, especially with special structures such as: unequal thickness welding, curved welding , Large-scale structure, etc., the upper pressure fixture is not easy to design and manufacture, and it will cost a lot of production costs. The follow-up upper pressure jig can reduce the cost of jig manufacturing and achieve tight upper holding by friction stir welding. However, when corresponding to special structures, it cannot meet the demand for flexible upper holding.

China Publication No. CN102672345A discloses a welding tool and a welding method for down-pressure friction stir welding suitable for thin plates. The welding-on-press friction stir welding tool includes a stirring head P1, a radial positioning bearing P2, a downward pressing slider P3 and a fixed frame P4, the radial positioning bearing P2 is sleeved on the external thread of the stirring head P1, and the slider is pressed down P3 is fixedly installed on the lower surface of the fixed frame P4 by bolts, the pressing slider P3 and the fixed frame P4 are integrated on the external thread of the mixing head P1, and the bearing P2 is gradually positioned on the outer diameter of the mixing head P1 and the fixed frame P4 Between the inner diameters of, the shaft shoulder of the stirring head P1 and the stirring needle are exposed outside the lower surface of the pressing slider P3. The specific steps of the welding method are as follows: Step one, fix the first welded work piece P5 and the second welded work piece P6 on the worktable with a fixture, so that the welding place of the first welded work piece P5 and the second welded work piece P6 The welding place is butted, and first the workpiece to be welded P5 and the second workpiece to be welded P6 are at the same level; Step 2, start the stirring head P1, the speed of the stirring head P1 is 200rpm~2000rpm, and the welding tool is rolled down to the first welded workpiece The welding start position of P5 and the second welded work piece P6 makes the lower surface of the pressing slider P3 closely contact the upper surface of the first welded work piece P5 and the second welded work piece P6, and the shoulder of the stirring head P1 is rolled The depth of the upper surface of the first welded work piece P5 and the second welded work piece P6 is equal to the distance between the lower surface of the pressing slider P3 and the two ends of the shaft shoulder of the stirring head P1); step three, the entire welding tool is at a speed (Vx) is 10mm/min~1000mm/min and moves along the length direction of the butt surface of the first welded workpiece P5 and the second welded workpiece P6 until the welding is completed.

The purpose of the present invention is to provide a friction stir welding holding fixture system, which uses a plurality of holding fixtures arranged on the side of the spindle axis, and these holding fixtures contact and work before the stirring head, and can maintain it. The pressure presses the workpiece while following the stirring head to move on the surface of the workpiece to be joined.

In order to achieve the above objective, the present invention provides a friction stir welding holding fixture system, which is applied to a friction stir welding equipment, which includes a spindle system including a non-rotating Area, the center of the non-rotating area is provided with a spindle axis, and the spindle axis is connected to a stirring head for rotation to perform friction stir welding on a workpiece to be joined. The pressing and holding fixture system includes: a pressing and holding fixture adjacent to On the non-rotating area and located on the side of the mixing head, the pressing jig has a base adjacent to the non-rotating area, a linear sliding mechanism connected to the base, and a linear sliding mechanism arranged on the linear sliding mechanism And connected to the rebound mechanism of the base and a contact portion provided at the end of the linear sliding mechanism, and when the stirring head does not contact the workpiece to be joined, the first surface of the contact portion protrudes from the stirring A second surface of the head; wherein the spindle system carries the stirring head and the holding fixtures to move a welding path within 3 spatial dimensions on the workpiece to be joined, the holding fixtures It is used to maintain a certain downward pressure on the surface of the workpiece to be joined adjacent to the stirring head, and when the spindle system moves along the welding path, it will slide on the surface of the workpiece to be joined while maintaining the downward pressure. surface.

In some embodiments, the non-rotating area has a shoulder facing the workpiece to be joined, and the holding fixtures are disposed on the shoulder.

In some embodiments, the shoulder has a third surface, and when the stirring head is not in contact with the workpiece to be joined, the height from the first surface to the third surface is greater than the height from the second surface to the third surface.

In some embodiments, the linear sliding mechanism includes a rod and the base has a cavity for the rod to nest, so as to form the linear sliding mechanism for axial movement of the rod, and the cavity Formed in the base.

In some embodiments, the rebound mechanism is a compression spring with front and rear ends respectively connected to the base and the rod.

In some embodiments, the rebound mechanism is a pair of magnetic elements respectively arranged on the base and the rod, and the magnetic poles repel each other.

In some embodiments, the contact portion is a pulley or a sphere that can roll with its own axis as the central axis.

In some embodiments, the contact portion is a non-rolling arc surface.

In some embodiments, the holding jigs are centered on the stirring head and arranged in an array in the bottom view direction of the spindle system.

In some embodiments of the present invention, the holding jigs are centered on the stirring head, and are uniformly distributed throughout the circumference of the spindle system in the bottom view direction.

In some embodiments of the present invention, the surfaces of the workpiece to be joined contacted by the contact portions of the pressing jigs are a curved surface or a first plane and a second plane that are not the same horizontal plane.

The present invention has at least the following features: the design of the present invention enables the holding fixture to achieve elastic displacement or magnetic buffer displacement in a certain interval, and achieve unequal height combinations of workpieces to be joined or curved surfaces to hold the upper part of the workpieces to be joined. The design of the invention can correspond to the clamping needs of special structures such as curved surfaces, large workpieces, and unequal thicknesses, and can correspond to the current development trend of a small number of products in the world; the invention can be used with three to five axis friction stirring special machines, robotic arms and other automation Equipment, greatly improve the efficiency of joining; the design of the fixture is simple, can correspond to a variety of joint changes, and can reduce the cost of fixture production. In the early stage of product trial development, it can respond to multiple product design changes without the need for additional fixture modification. The invention provides a new type of friction stir fixture solution with 3D structure, which can promote the friction stir welding process in special structure aluminum alloys, such as curved weld beads and welding applications with different levels on the two sides of the weld beads.

P2: Positioning bearing

P3: Press down the slider

P4: Fixed frame

P5: The first workpiece to be welded

P6: The second workpiece to be welded

Vx: speed

1: Holding fixture system

2: Spindle system

21: Non-rotating area

211: Shoulder

2111: third surface

22: Spindle axis

P1, 23: Mixing head

231: second surface

3: Holding fixture

31: Pedestal

311: cavities

312: Rod

32: Linear sliding mechanism

33,33’: Rebound mechanism

331: Compression spring

332: Magnetic components

34: contact part

340: First Surface

341: Pulley

342: Sphere

343: Globoid

D: Direction of travel

L1, L2: height

T1, T2: thickness

S: Workpiece surface

S1: Surface of the first workpiece

S2: Second workpiece surface

R: welding path

W: Workpiece to be joined

W1: The first workpiece

W2: The second workpiece

[Figure 1] is a schematic cross-sectional view of the prior art welding-on-press friction stir welding tool; [Figure 2] is a front view of the friction stir welding holding jig without contacting the workpiece to be joined according to an embodiment of the present invention Partial view; [FIG. 3] is a front view of the friction stir welding holding fixture in the embodiment of FIG. 2 and pressing the workpiece; [FIG. 4] is a view of the rebound mechanism of an embodiment of the present invention is a compression spring type, pressure The contact part of the holding jig is a schematic cross-sectional view of the pulley; [Figure 5] is a schematic cross-sectional view of the contact part of the holding jig as a sphere according to an embodiment of the present invention; [Figure 6] is the rebound mechanism of an embodiment of the present invention Fig. 7 is a cross-sectional schematic diagram of a magnetic field type holding fixture; [Fig. 7] is a schematic cross-sectional view of a friction stir welding holding jig applied to workpieces with unequal heights; [Fig. 8] is a first embodiment of the present invention [FIG. 9] is a bottom view schematic diagram of the pressing and holding fixtures distributed in a matrix according to an embodiment of the present invention; and [FIG. 10] is an embodiment of the present invention The side cross-sectional view of the pressing and holding jig actuated on the surface of the workpiece to be joined as a curved surface.

The embodiments of the present invention are described in detail below in conjunction with the drawings. The accompanying drawings are mainly simplified schematic diagrams, which only schematically illustrate the basic structure of the present invention. Therefore, only elements related to the present invention are indicated in these drawings. And the displayed components are not drawn based on the number, shape, size ratio, etc. of the actual implementation. The actual size of the actual implementation is a selective design, and the layout of the components may be more complicated.

The description of the following embodiments refers to the attached drawings to illustrate specific embodiments according to which the present invention can be implemented. The directional terms mentioned in the present invention, such as "up", "down", "front", "rear", "left", "right", "inner", "outer", "side", etc., are for reference only The direction of the additional schema. Therefore, the directional terms used are used to illustrate and understand the application, rather than to limit the application. In addition, in the specification, unless expressly described to the contrary, the word "including" It will be understood to mean including the described elements, but not excluding any other elements.

Please refer to Figure 2 and Figure 3. The friction stir welding holding fixture system 1 of this embodiment is suitable for use in friction stir welding equipment. The friction stir welding equipment has a spindle system 2 that includes a movable non-rotating area 21 located on the periphery. With the spindle shaft 22 located in the center and capable of rotating simultaneously during movement, a stirring head 23 connected to the spindle shaft 22, or a stirring tool, is used to perform friction stir welding operations on a workpiece W to be joined. The holding fixture system 1 includes: The pressing jig 3 is adjacent to the side of the stirring head 23 in the non-rotating area 21. Referring to FIGS. 2 and 3, in one embodiment, there are a plurality of pressing jigs 3, and the arrangement can be evenly distributed, or it can focus on the welding travel direction to be multiple. The pressing jig 3 has a base 31 adjacent to the non-rotating area 21, a linear sliding mechanism 32 connected to the base 31, and a linear sliding mechanism 32 arranged on the linear sliding mechanism 32 and connected to the base 31 The rebound mechanism 33 and a contact portion 34 provided at the end of the linear sliding mechanism 33. In another embodiment, the holding fixture 3 may be one and surround the stirring head 23 in a continuous manner.

According to the aforementioned structural design, after the above-mentioned holding jig 3 is arranged in the spindle system 2 in the present invention, when the stirring head 23 does not contact the workpiece W to be joined, the contact portion 34 faces the foremost edge of the workpiece W to be joined A first surface 340 protrudes from a second surface 231 at the end of the stirring head 23. In one embodiment, the non-rotating area 21 has a shoulder 211 facing the workpiece W to be joined, and the shoulder 211 has a third surface 2111. When the stirring head 23 does not contact the workpiece W to be joined, the first The height L1 from the first surface 340 to the third surface 2111 is greater than the height L2 from the second surface 231 to the third surface 2111. (As shown in Figure 2); Therefore, when the friction stir welding operation is performed and the spindle system 2 is close to the workpiece W to be joined, the stirring head 23 is about to contact the workpiece W to be joined, the pressing and holding The contact portion 34 of the jig 3 will contact the workpiece W to be joined before the stirring head 23 to generate a downward pressing force (as shown in FIG. 3), so that the workpiece W (especially thin-shaped) The plate) is kept in the best conforming state to facilitate the subsequent construction accuracy of the mixing head 23. The above-mentioned spindle system 2 carries the stirring head 21 and the holding fixtures 3 on the workpiece W to be joined to move a welding path R in a range of 3 spatial dimensions, including a 2-dimensional plane and a 3-dimensional space, The holding jigs 3 are used to maintain a certain downward pressure on the surface of the workpiece W to be joined near the stirring head 3, and when the spindle system 2 moves along the welding path R, the downward pressure is maintained The lower part slides on the workpiece surface S of the workpiece W to be joined, and since each pressing jig 3 has an independent linear sliding mechanism 32 and a rebound mechanism 33, it can individually contact the workpiece surface S fluctuates in response to displacement (as shown in Figure 10).

In some embodiments of the present invention, the linear sliding mechanism 32 includes a rod 321 and a cavity 311 into which the rod 312 is nested, and the cavity 311 is formed in the base 31 so that the The rod 312 can reciprocate along the center longitudinal axis of the rod 321.

As shown in FIG. 5, in some embodiments of the present invention, the rebound mechanism 33 may be a compression spring 331, the front and rear ends of the compression spring 331 are respectively connected to the base 31 and the rod 312 , The rod 312 is used to reciprocate on the linear sliding mechanism 32.

As shown in FIG. 6, in some embodiments of the present invention, the resilience mechanism 33' may be a pair of magnetic elements 332 respectively disposed on the base 31 and the rod 312 and with magnetic poles repelling each other, so that the rod may be used The piece 312 reciprocates on the linear sliding mechanism 32.

as shown in picture 2. In some embodiments of the present invention, the above-mentioned pressing jig 3 can be arranged at a reasonable position of the non-rotating area 21, for example, arranged in the non-rotating area 21 facing the shoulder 211 of the workpiece W to be joined. 2 is set on the shoulder 211. Of course, in some embodiments, the holding fixtures 3 can also be arranged in the non-rotating area 21 perpendicular to the shoulder 211. The side elevation can solve the problem of insufficient space in the shoulder 211 area and unable to accommodate the holding fixtures 3.

It is worth mentioning that the holding fixtures 3 of the present invention are of modular design, so they can be externally mounted on existing friction stir welding equipment to upgrade the original friction stir welding equipment.

In some embodiments, the contact portion 34 is in contact with the workpiece W to be joined in a form of low friction. In one embodiment, as shown in FIG. 4 and FIG. 5. Fig. 4 shows the contact part 34 of the present invention in the form of a rolling pulley 341 (contact with the workpiece W to be joined is line contact), and Fig. 5 discloses the contact part 34 of the present invention in the form of a rolling sphere 342 ( The contact with the workpiece W to be joined is a point contact). Of course, in another embodiment, as shown in FIG. 6, the contact portion 34 of the present invention may also be in the form of a non-rolling arc surface 343 (the contact with the workpiece W to be joined is a line contact or a point contact) , Can also reduce its contact friction. In another embodiment, the contact portion 34 is made of a material with a low friction coefficient, such as polytetrafluoroethylene (Teflon).

In some embodiments, as shown in FIGS. 3 and 7, the workpiece W to be joined includes a first workpiece W1 and a second workpiece W2, and the joint of the first workpiece W1 and the second workpiece W2 is a welding Path R. In the embodiment of FIG. 7, it is disclosed that the pressing jig 3 and the workpiece W to be joined are in contact with a first workpiece surface S1 of the first workpiece W1 and a second workpiece surface S2 of the second workpiece W2 that are not in the same horizontal plane. The thickness T1 of the first workpiece W1 is greater than the thickness T2 of the second workpiece W2. Therefore, the surface S1 of the first workpiece is higher than the surface S2 of the second workpiece. The design of the linear sliding mechanism 32 and the rebound mechanism 33 of the jig 3 can be moved on the first workpiece surface S1 and the second workpiece surface S2 while still or moving while holding pressure; or as shown in Figure 10 It is shown that the workpiece surface S of the workpiece to be joined W contacted by the contact portions 34 of the pressing jigs 3 is a curved surface.

In some embodiments, as shown in FIG. 8. The holding fixtures 3 are centered on the stirring head 23, and are arranged in an array in the bottom view direction of the spindle system 2 (that is, the bottom view direction of the stirring head 23); in some embodiments, as shown in FIG. 9 shown. The holding jigs 3 are centered on the stirring head 23, and are uniformly distributed throughout the circumference in the bottom view direction of the spindle system 2 (that is, the bottom view direction of the stirring head 23).

The above-disclosed embodiments only illustrate the principles, features, and effects of the present invention, and are not intended to limit the scope of the present invention. Anyone familiar with the art can do so without departing from the spirit and scope of the present invention. Modifications and changes are made to the above-mentioned embodiments. Any equivalent changes and modifications made by using the contents disclosed in the present invention shall still be covered by the following patent application scope.

1: Holding fixture system

2: Spindle system

21: Non-rotating area

211: Shoulder

22: Spindle axis

23: Mixing head

3: Holding fixture

31: Pedestal

311: cavities

312: Rod

32: Linear sliding mechanism

33: Rebound mechanism

34: contact part

S: Workpiece surface

R: welding path

W: Workpiece to be joined

W1: The first workpiece

W2: The second workpiece

Claims (8)

A friction stir welding holding fixture system, suitable for a friction stir welding equipment. The friction stir welding equipment also includes a spindle system. The spindle system includes a non-rotating area at the periphery and a rotating spindle at the center. The shaft center and a stirring head connected to the shaft center of the main shaft. The friction stir welding equipment is used to perform friction stir welding on a workpiece to be joined. The holding fixture system includes: a plurality of holding fixtures adjacent to the non- The rotating area is located on the side of the stirring head, and each of the holding fixtures has a base adjacent to the non-rotating area, a linear sliding mechanism connected to the base, and a linear sliding mechanism disposed on the linear sliding mechanism And connected to the rebound mechanism of the base and a contact portion provided at the end of the linear sliding mechanism. When the stirring head does not contact the workpiece to be joined, a first surface of the contact portion protrudes from the A second surface of the mixing head; wherein the non-rotating area has a shoulder facing the workpiece to be joined, and the pressing jigs are arranged on the shoulder; wherein the shoulder has a third surface, When the stirring head is not in contact with the workpiece to be joined, the height from the first surface to the third surface is greater than the height from the second surface to the third surface. The friction stir welding pressing jig system according to claim 1, wherein the linear sliding mechanism includes a rod and a cavity for the rod to nest, and the cavity is formed in the base. The friction stir welding pressing jig system according to claim 2, wherein the rebound mechanism is a compression spring whose front and rear ends are respectively connected to the base and the rod. The friction stir welding pressing jig system according to claim 2, wherein the rebound mechanism is a pair of magnetic elements respectively arranged on the base and the rod, and having magnetic poles repelling each other. The friction stir welding holding fixture system according to claim 1, wherein the contact part is a pulley or a sphere that can roll with its own axis as the central axis. The friction stir welding holding fixture system according to claim 1, wherein the contact portion is a non-rolling arc surface. The friction stir welding holding fixture system according to claim 1, wherein the holding fixtures are centered on the stirring head and arranged in an array in the bottom view direction of the spindle system. The friction stir welding holding jig system according to claim 1, wherein the holding jigs are centered on the stirring head, and are uniformly distributed over the entire circumference in the bottom view direction of the main shaft system.

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