CN103042303B - Friction stir welding fixture in mechanical trigger control mode and method for controlling friction stir welding fixture - Google Patents
Friction stir welding fixture in mechanical trigger control mode and method for controlling friction stir welding fixture Download PDFInfo
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- CN103042303B CN103042303B CN201210567498.0A CN201210567498A CN103042303B CN 103042303 B CN103042303 B CN 103042303B CN 201210567498 A CN201210567498 A CN 201210567498A CN 103042303 B CN103042303 B CN 103042303B
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- friction stir
- elastic spring
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- 238000003466 welding Methods 0.000 title claims abstract description 109
- 238000003756 stirring Methods 0.000 title claims abstract description 33
- 238000000034 method Methods 0.000 title claims abstract description 19
- 238000003825 pressing Methods 0.000 claims description 34
- 230000008569 process Effects 0.000 claims description 8
- 230000007257 malfunction Effects 0.000 abstract 1
- 239000000463 material Substances 0.000 description 5
- 238000005304 joining Methods 0.000 description 3
- 239000007790 solid phase Substances 0.000 description 3
- 230000001788 irregular Effects 0.000 description 2
- 230000009467 reduction Effects 0.000 description 2
- 229910000838 Al alloy Inorganic materials 0.000 description 1
- 230000009471 action Effects 0.000 description 1
- 238000010586 diagram Methods 0.000 description 1
- 238000009826 distribution Methods 0.000 description 1
- 239000000428 dust Substances 0.000 description 1
- 230000004907 flux Effects 0.000 description 1
- 238000005242 forging Methods 0.000 description 1
- 230000004927 fusion Effects 0.000 description 1
- 230000004048 modification Effects 0.000 description 1
- 238000012986 modification Methods 0.000 description 1
- 230000001681 protective effect Effects 0.000 description 1
- 239000000779 smoke Substances 0.000 description 1
- 238000006467 substitution reaction Methods 0.000 description 1
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Abstract
The invention discloses a friction stir welding fixture in a mechanical trigger control mode and a method for controlling the friction stir welding fixture. The friction stir welding fixture comprises a fixture base, a control unit, a trigger element, limit switches and a plurality of pressure plates; each pressure plate is connected with a pressure plate cylinder, each pressure plate cylinder corresponds to at least one limit switch and is controlled by the corresponding limit switches, and the limit switches and the pressure plate cylinders are connected with the control unit; and the trigger element and the limit switches are matched with one another and are mounted on a friction stir welding head. The pressure plate cylinders are controlled by the mechanical trigger type limit switches and the trigger element, possibility of malfunction of the pressure plate cylinders is eliminated, the pressure plates are driven by the pressure plate cylinders to be automatically opened before the welding head moves to the pressure plates during movement, and are reset to press workpieces after the welding head passes the pressure plates, the integral fixture is automatically controlled and is reliable in running, and the cost is lowered.
Description
Technical Field
The invention relates to a welding fixture, in particular to a mechanical trigger control mode fixture for friction stir welding, which is particularly suitable for multi-edge welding seams, closed curve welding seams, irregular shapes and the like.
Background
Friction Stir Welding (FSW) was invented by the british institute of Welding (TWI) in 1991, and is an innovative solid phase joining technique that is derived from conventional Friction Welding and is relatively suitable for Welding long straight welds. Compared with the traditional fusion welding method, the friction stir welding has the advantages of fine weld grains, no smoke and dust, no splashing, no air holes, no welding flux, no protective gas during welding, small stress and deformation of the welded workpiece and the like, and is particularly suitable for welding aluminum alloy.
Friction stir welding is a purely mechanical continuous solid phase joining method, as shown in fig. 1, in the welding process, a cylindrical welding head with a special shoulder and a pin (i.e. a stirring head) rotates, the stirring head is slowly inserted into a part to be welded of a workpiece to be welded, frictional shear resistance between the stirring head and the material to be welded generates frictional heat, so that the material is softened and plastically deformed, when the welding head is driven to move forward along an interface to be welded, the thermoplasticized material is transferred from the front part to the rear part of the stirring head, and under the forging action of the shoulder of the welding head, solid phase joining between the workpieces is realized.
In the friction stir welding process, the workpiece needs to be pressed by a pressing plate, when the welding seam of the workpiece is a polygon or a closed curve or an irregular shape, taking a rectangular welding seam as an example, a hollow square workpiece is positioned on the outer side of another square workpiece, the hollow square workpiece is called an outer workpiece, the other square workpiece is called an inner workpiece, and the pressing plate needs to extend from the periphery of the outer workpiece and cross the welding seam to press on the inner workpiece. Therefore, when welding, the welding head travels in a closed square track, and the pressure plate can block the operation of the welding head during the movement of the welding head, so that an automatically controlled clamp is needed. At present, the opening and closing of the pressing plate are mainly controlled through the pressing plate cylinder, the pressing plate cylinder is controlled through the photoelectric sensor, when stirring and welding are conducted, the welding head can produce strip-shaped extruded materials, the extruded materials can interfere with the photoelectric sensor, and therefore misoperation of the pressing plate cylinder is caused.
Disclosure of Invention
The invention aims to solve the technical problem of providing a mechanical trigger control mode clamp for friction stir welding and a control method thereof, which can eliminate the possibility of causing misoperation of a pressure plate cylinder, improve the operation reliability and reduce the cost.
In order to solve the technical problem, the mechanical trigger control mode clamp for friction stir welding provided by the invention comprises a clamp base, a control unit, a trigger element, limit switches and a plurality of pressure plates, wherein each pressure plate is connected with a pressure plate cylinder, each pressure plate cylinder corresponds to at least one limit switch and is controlled by the corresponding limit switch, and the limit switches and the pressure plate cylinders are connected with the control unit; the trigger element is matched with the limit switch and is arranged on a welding head of the friction stir welding.
Furthermore, the limit switch and the trigger element are matched with each other to form an elastic spring, the elastic spring spans the welding seam, two ends of the elastic spring are respectively positioned at two sides of the welding seam, one end of the elastic spring is fixed on the limit switch, and the other end of the elastic spring is a free end. The trigger element is a push rod for pushing the elastic spring to bend, and the push rod is coaxial with the main shaft of the welding head.
Wherein, the control unit is a PLC.
Furthermore, the limit switch corresponding to each pressure plate cylinder is positioned in front of the pressure plate controlled by the pressure plate cylinder on the moving track of the welding head.
Wherein, the limit switch is one, or two or more than two in parallel.
The invention also provides a control method of the mechanical trigger control mode clamp for friction stir welding, which comprises the following steps:
the inner workpiece and the outer workpiece to be welded are positioned on the clamp base, and the pressing plate cylinder controls the pressing plate to tightly press the inner workpiece;
under the control of a control unit, a welding head drives a trigger element to start running by taking one position of a welding seam as a starting point, the trigger element contacts a certain limit switch on a running track, the limit switch sends a signal to the control unit, the control unit sends an opening instruction to a pressure plate cylinder corresponding to the limit switch, the pressure plate cylinder drives a pressure plate connected with the pressure plate cylinder to rotate so that the welding head passes through the pressure plate cylinder, after the trigger element passes through the limit switch, the limit switch sends a signal to the control unit, the control unit sends a reset instruction to the pressure plate cylinder corresponding to the limit switch, and the pressure plate cylinder drives the pressure plate connected with the pressure plate cylinder to reset so as to press an inner workpiece again;
and the welding head continuously moves forwards along the welding line, the trigger elements are contacted with the rest limit switches one by one, the pressure plate cylinders corresponding to the limit switches drive the pressure plates to rotate one by one to enable the welding head to pass through until the welding head returns to the starting point of the welding line, and the control unit drives all the pressure plate cylinders to drive the pressure plates to rotate and open to finish the welding process.
Further, under the control of the control unit, the welding head drives the trigger element to start to operate by taking one position of a welding seam as a starting point, the trigger element pushes an elastic spring of a certain limit switch on an operation track and bends the elastic spring, the limit switch sends a signal to the control unit, the control unit sends an opening instruction to a pressure plate cylinder corresponding to the limit switch, the pressure plate cylinder drives a pressure plate connected with the pressure plate cylinder to rotate so that the welding head passes through, the trigger element passes through the limit switch, the elastic spring on the limit switch returns to the original state, the limit switch sends a signal to the control unit, the control unit sends a resetting instruction to the pressure plate cylinder corresponding to the limit switch, and the pressure plate cylinder drives the pressure plate connected with the pressure plate cylinder to reset so as to press the inner workpiece again; the welding head continues to move forwards along the welding line, the trigger element pushes away the elastic springs of the rest limit switches one by one, the pressure plate cylinder corresponding to the limit switch drives the pressure plate to rotate one by one to enable the welding head to pass through until the welding head returns to the starting point of the welding line, and the control unit drives all the pressure plate cylinders to drive the pressure plate to rotate and open to finish the welding process.
The pressing plate cylinder drives the pressing plate to rotate after receiving the opening instruction and the set first delay, the pressing plate cylinder drives the pressing plate to reset after receiving the reset instruction and the set second delay, and the first delay and the second delay are set by the control unit.
The invention adopts the mechanical contact limit switch and the trigger element to control the pressure plate cylinder, thereby eliminating the possibility of causing the misoperation of the pressure plate cylinder, and in the moving process of the welding head, the pressure plate is automatically opened under the driving of the pressure plate cylinder before the welding head moves to the self position, and the welding head resets and presses the workpiece after passing through the self position, thereby realizing the automatic control of the whole clamp, reliable operation and cost reduction.
Drawings
FIG. 1 is a schematic illustration of friction stir welding;
FIG. 2 is a schematic view of the structure of the jig of the present invention;
fig. 3 is a schematic diagram of the trigger element and limit switch of the present invention.
Wherein the reference numerals are as follows:
1 limit switch 2 pressure plate
3 clamp plate cylinder 4 clamp base
5 welding head 6 trigger element
7 elastic spring
Detailed Description
The present invention will be described in further detail with reference to the accompanying drawings and specific embodiments.
The mechanical trigger control mode clamp for friction stir welding, as shown in fig. 2, comprises a clamp base 4, a control unit (in this embodiment, a PLC), a trigger element 6, a limit switch 1 and six press plates 2, wherein each press plate 2 is connected with one press plate cylinder 3, and each press plate cylinder 3 corresponds to at least one limit switch 1 and is controlled by the corresponding limit switch 1. The limit switch 1 corresponding to each platen cylinder 3 is located in front of the platen 2 controlled by the platen cylinder 3 on the moving track of the welding head 5. In the embodiment, in order to improve the contact reliability of the trigger element 6 and the limit switches 1 and ensure the accuracy of automatic control of the clamp, two limit switches 1 are arranged in front of each pressure plate 2 in parallel. And the limit switch 1 and the pressure plate cylinder 3 are both connected with a control unit.
In the present embodiment, as shown in fig. 3, the limit switch 1 and the trigger element 6 are matched with an elastic spring 7, the elastic spring 7 spans over the weld joint, two ends of the elastic spring 7 are respectively located at two sides of the weld joint, one end of the elastic spring is fixed on the limit switch 1, and the other end is a free end. The trigger element 6 is a push rod for pushing the elastic spring 7 to bend, is arranged on the welding head 5 of the friction stir welding and is coaxial with the main shaft of the welding head 5.
The control method of the mechanical trigger control mode clamp for friction stir welding in the embodiment comprises the following steps:
an inner workpiece and an outer workpiece to be welded are positioned on a clamp base 4, and a pressure plate cylinder 3 controls a pressure plate 2 to tightly press the inner workpiece;
under the control of a control unit, a welding head 5 drives a trigger element 6 to start to operate by taking one position of a welding seam as a starting point, the trigger element 6 pushes an elastic spring 7 of a certain limit switch 1 on an operation track and bends the elastic spring 7, the limit switch 1 sends a signal to the control unit, the control unit sends an opening instruction to a pressure plate cylinder 3 corresponding to the limit switch 1, the pressure plate cylinder 3 drives a pressure plate 2 connected with the pressure plate cylinder 3 to rotate so that the welding head 5 passes through, the trigger element 6 passes through the limit switch 1, the elastic spring 7 on the limit switch 1 returns to the original state, the limit switch 1 sends a signal to the control unit, the control unit sends a reset instruction to the pressure plate cylinder 3 corresponding to the limit switch 1, and the pressure plate cylinder 3 drives the pressure plate 2 connected with the pressure plate cylinder 3 to reset so as to press an inner workpiece again; the welding head 5 continues to move forwards along the welding line, the trigger element 6 pushes away the elastic springs 7 of the rest limit switches 1 one by one, the pressure plate cylinder 3 corresponding to the limit switch 1 drives the pressure plate 2 to rotate one by one to enable the welding head 5 to pass through until the welding head 5 returns to the starting point of the welding line, and the control unit drives all the pressure plate cylinders 3 to drive the pressure plate 2 to rotate and open to finish the welding process.
The pressing plate cylinder 3 drives the pressing plate 2 to rotate after receiving the opening instruction and the set first delay, and drives the pressing plate 2 to reset after receiving the reset instruction and the set second delay, and the first delay and the second delay are set by the control unit.
The invention adopts the mechanical contact limit switch and the trigger element to control the pressure plate cylinder, thereby eliminating the possibility of causing the misoperation of the pressure plate cylinder, and in the moving process of the welding head, the pressure plate is automatically opened under the driving of the pressure plate cylinder before the welding head moves to the self position, and the welding head resets and presses the workpiece after passing through the self position, thereby realizing the automatic control of the whole clamp, reliable operation and cost reduction.
The present invention has been described in detail with reference to the specific embodiments, which are only the preferred embodiments of the present invention and are not intended to limit the present invention. Equivalent substitutions and modifications of the number and distribution positions of the pressure plates, the number and positions of the limit switches, and the like, by those skilled in the art, without departing from the principles of the present invention, should be considered to be within the scope of the protection technology of the present invention.
Claims (7)
1. A mechanical trigger control mode clamp for friction stir welding is characterized by comprising a clamp base (4), a control unit, a trigger element (6), limit switches (1) and a plurality of pressing plates (2), wherein each pressing plate (2) is connected with a pressing plate cylinder (3), each pressing plate cylinder (3) corresponds to at least one limit switch (1) and is controlled by the corresponding limit switch (1), and the limit switches (1) and the pressing plate cylinders (3) are connected with the control unit; the trigger element (6) is matched with the limit switch (1) and is arranged on a welding head (5) of friction stir welding;
the limiting switch (1) and the trigger element (6) are matched with each other to form an elastic spring (7), the elastic spring (7) spans the welding seam, two ends of the elastic spring (7) are respectively located on two sides of the welding seam, one end of the elastic spring is fixed on the limiting switch (1), the other end of the elastic spring is a free end, and the elastic spring (7) provides a starting signal and a reset signal for the control unit.
2. Mechanical trigger control mode clamp for friction stir welding according to claim 1, characterized in that said trigger element (6) is a push rod pushing the elastic spring (7) to bend, coaxial to the main axis of the welding head (5).
3. The friction stir welding mechanically activated control mode clamp of claim 1 wherein the control unit is a PLC.
4. Mechanical trigger control mode clamp for friction stir welding according to claim 1, characterized in that the limit switch (1) corresponding to each platen cylinder (3) is located in front of the platen (2) controlled by the platen cylinder (3) on the trajectory of the welding head (5).
5. The friction stir welding mechanically activated control mode clamp of claim 1 wherein the limit switch is one or more than two in parallel.
6. The method of controlling a friction stir welding mechanically activated control mode clamp of claim 1,
the inner workpiece and the outer workpiece needing to be welded are positioned on the clamp base (4), and the pressing plate cylinder (3) controls the pressing plate (2) to press the inner workpiece;
the limiting switch (1) is matched with the trigger element (6) to form an elastic spring (7), the elastic spring (7) stretches across the weld joint, one end of the elastic spring is fixed on the limiting switch (1), and the other end of the elastic spring is a free end; the trigger element (6) is a push rod for pushing the elastic spring (7) to bend, and is coaxial with the main shaft of the welding head (5); wherein,
under the control of a control unit, a welding head (5) drives a trigger element (6) to start to operate by taking one position of a welding seam as a starting point, the trigger element (6) pushes an elastic spring (7) of a certain limit switch (1) and bends the elastic spring (7) on an operation track, the limit switch (1) sends a signal to the control unit, the control unit sends an opening instruction to a pressing plate cylinder (3) corresponding to the limit switch (1), the pressing plate cylinder (3) drives a pressing plate (2) connected with the pressing plate cylinder to rotate so that the welding head (5) passes through, the trigger element (6) passes through the limit switch (1), the elastic spring (7) on the limit switch (1) restores to the original state, the limit switch (1) sends a signal to the control unit, and the control unit sends a resetting instruction to the pressing plate cylinder (3) corresponding to the limit switch (1), the pressing plate cylinder (3) drives the pressing plate (2) connected with the pressing plate cylinder to reset and press the inner workpiece again; the welding head (5) continues to move forwards along the welding line, the trigger element (6) pushes away the elastic springs (7) of the rest limit switches (1) one by one, the pressing plate cylinder (3) corresponding to the limit switches (1) drives the pressing plates (2) to rotate one by one to enable the welding head (5) to pass through until the welding head (5) returns to the starting point of the welding line, and the control unit drives all the pressing plate cylinders (3) to drive the pressing plates (2) to rotate and open to finish the welding process.
7. The method for controlling the clamp in the mechanical trigger control mode of friction stir welding according to claim 6, wherein the pressure plate cylinder (3) drives the pressure plate (2) to rotate after receiving the opening command and after a set first delay, and drives the pressure plate (2) to reset after receiving the reset command and after a set second delay, and the first delay and the second delay are set by the control unit.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN201210567498.0A CN103042303B (en) | 2012-12-24 | 2012-12-24 | Friction stir welding fixture in mechanical trigger control mode and method for controlling friction stir welding fixture |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN201210567498.0A CN103042303B (en) | 2012-12-24 | 2012-12-24 | Friction stir welding fixture in mechanical trigger control mode and method for controlling friction stir welding fixture |
Publications (2)
| Publication Number | Publication Date |
|---|---|
| CN103042303A CN103042303A (en) | 2013-04-17 |
| CN103042303B true CN103042303B (en) | 2017-03-22 |
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| CN201210567498.0A Active CN103042303B (en) | 2012-12-24 | 2012-12-24 | Friction stir welding fixture in mechanical trigger control mode and method for controlling friction stir welding fixture |
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Families Citing this family (2)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN103753014A (en) * | 2014-01-02 | 2014-04-30 | 联合汽车电子有限公司 | Clamping device for friction stir welding |
| CN108406193B (en) * | 2018-03-02 | 2020-12-18 | 宁波友智机械科技有限公司 | Automatic welding clamp for friction stir welding and control method thereof |
Citations (8)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| US4444379A (en) * | 1982-01-11 | 1984-04-24 | Fmc Corporation | Trigger release clamp |
| CN101362268A (en) * | 2007-08-07 | 2009-02-11 | 庄添财 | Bicycle front Y-type pipe welding bench |
| CN202028893U (en) * | 2011-04-19 | 2011-11-09 | 浙江吉利汽车研究院有限公司 | Manual locking mechanism arranged on welding fixture |
| CN202037431U (en) * | 2011-04-30 | 2011-11-16 | 桂林电子科技大学 | Hand-held electric lead screw flash butt welding clamping device |
| CN202129576U (en) * | 2011-04-26 | 2012-02-01 | 安徽瑞祥工业有限公司 | Welding jig position-restricted switch |
| CN102642107A (en) * | 2012-04-28 | 2012-08-22 | 长城汽车股份有限公司 | Workpiece locating device of multi-motorcycle-type welding production line of general motors |
| CN202607069U (en) * | 2011-05-10 | 2012-12-19 | 广州东昇机械有限公司 | Welding device with eccentric electrode |
| CN203018906U (en) * | 2012-12-24 | 2013-06-26 | 联合汽车电子有限公司 | Mechanical triggering control mode clamp for friction stir welding tool |
-
2012
- 2012-12-24 CN CN201210567498.0A patent/CN103042303B/en active Active
Patent Citations (8)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| US4444379A (en) * | 1982-01-11 | 1984-04-24 | Fmc Corporation | Trigger release clamp |
| CN101362268A (en) * | 2007-08-07 | 2009-02-11 | 庄添财 | Bicycle front Y-type pipe welding bench |
| CN202028893U (en) * | 2011-04-19 | 2011-11-09 | 浙江吉利汽车研究院有限公司 | Manual locking mechanism arranged on welding fixture |
| CN202129576U (en) * | 2011-04-26 | 2012-02-01 | 安徽瑞祥工业有限公司 | Welding jig position-restricted switch |
| CN202037431U (en) * | 2011-04-30 | 2011-11-16 | 桂林电子科技大学 | Hand-held electric lead screw flash butt welding clamping device |
| CN202607069U (en) * | 2011-05-10 | 2012-12-19 | 广州东昇机械有限公司 | Welding device with eccentric electrode |
| CN102642107A (en) * | 2012-04-28 | 2012-08-22 | 长城汽车股份有限公司 | Workpiece locating device of multi-motorcycle-type welding production line of general motors |
| CN203018906U (en) * | 2012-12-24 | 2013-06-26 | 联合汽车电子有限公司 | Mechanical triggering control mode clamp for friction stir welding tool |
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| CN103042303A (en) | 2013-04-17 |
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