Double-shoulder welding device and welding method

Abstract

The present invention discloses a double-shoulder welding device and a welding method provided by the present invention. The double-shoulder welding device includes a shell, a stirring assembly and a pulling assembly. The stirring assembly includes a rotatable stirring head, and the stirring head has an upper shoulder and a lower shoulder that are relatively arranged. The pulling assembly is transmission-connected to the stirring head to adjust the position of the stirring head along the axial direction. The control assembly includes a sensor and a controller. The sensor is used to monitor the pulling force applied by the pulling assembly to the stirring head. The controller is communicatively connected to the sensor and the pulling assembly, respectively, and adjusts the position of the stirring head according to the signal fed back by the sensor to maintain the stability of the pulling force applied by the pulling assembly to the stirring head. In this way, the distance between the lower shoulder and the surface of the workpiece is kept stable, thereby improving the welding quality of the workpiece.

Description

Technical Field

[0001] The invention relates to the technical field of welding, and in particular to a double-shoulder welding device and a welding method. Background Art

[0002] Double-shoulder friction stir welding is an extension technology of traditional friction stir welding. It is suitable for welding hollow components and medium and thick plates, and has broad application prospects in aviation, aerospace, shipbuilding and other fields.

[0003] The existing double-shoulder welding stirring head can be found in patent application number CN201210343343.9. During double-shoulder friction stir welding, the upper and lower shoulders and the stirring needle rotate simultaneously and generate heat by friction with the workpiece. Under the strong friction and stirring action, the weld metal is plasticized and squeezed to the rear side of the stirring head by rotation, thus forming a weld. The distance between the lower shoulder and the workpiece surface directly affects the welding quality of the workpiece, but the workpiece surface is often not flat, which causes the distance between the lower shoulder and the workpiece surface to change slightly, affecting the final welding quality.

[0004] Therefore, how to maintain a stable distance between the lower shoulder and the workpiece surface is a technical problem that needs to be solved urgently. Summary of the invention

[0005] The purpose of the present invention is to overcome the above technical deficiencies, and to provide a double-shoulder welding device and a welding method to solve the technical problem in the prior art of how to maintain a stable spacing between the lower shoulder and the workpiece surface.

[0006] In order to achieve the above technical objectives, the present invention adopts the following technical solutions: In one aspect, the present invention provides a double-shoulder welding device, comprising: case; A stirring assembly, comprising a rotatable stirring head, wherein the stirring head has an upper shoulder and a lower shoulder arranged opposite to each other; A pulling assembly, which is drivingly connected to the stirring head to adjust the position of the stirring head along the axial direction; and A control component includes a sensor and a controller, wherein the sensor is used to monitor the pulling force applied by the pulling component to the stirring head, and the controller is communicatively connected to the sensor and the pulling component respectively, and adjusts the position of the stirring head according to the signal fed back by the sensor to maintain the stability of the pulling force applied by the pulling component to the stirring head.

[0007] In some embodiments, the stirring assembly includes a first sleeve, a stirring shaft and a driving member. The first sleeve is rotatably embedded in the shell, the stirring shaft is coaxially embedded in the first sleeve, and the stirring shaft can slide axially relative to the first sleeve. The stirring head is installed at one end of the stirring shaft, and the driving member drives the first sleeve to rotate.

[0008] In some embodiments, the pulling assembly includes a pulling member and a connecting member, the connecting member having a first connecting end and a second connecting end that can rotate relative to each other, the first connecting end is connected to the stirring shaft, and the pulling member is connected to the second connecting end, which drags the stirring shaft to move axially via the connecting member.

[0009] In some embodiments, the pulling member includes a pulling motor, a second sleeve and a screw rod, the inner wall of the second sleeve has a thread, one end of the screw rod is threadedly connected to the thread, and the other end of the screw rod is fixedly connected to the connecting end, and the pulling motor drives the second sleeve to rotate.

[0010] In some embodiments, the pulling motor is a servo motor, and the sensor is a torque sensor that detects the output torque of the servo motor.

[0011] In some embodiments, the driving member includes an outer rotor and an inner rotor, the outer rotor is built into the housing, the inner rotor is embedded in the inner rotor, and the inner rotor is sleeved on the outer periphery of the first sleeve.

[0012] In some embodiments, a slide groove is formed on the inner wall of the first sleeve along the axial direction, and a slide key is formed on the outer wall of the stirring shaft, and the slide key is slidably disposed in the slide groove.

[0013] In some embodiments, the lower shoulder is detachably connected to the upper shoulder.

[0014] On the other hand, the present invention also provides a double-shoulder welding method, which is used for the above-mentioned double-shoulder welding device, and comprises: S1. Adjust the position of the stirring head so that the upper and lower shoulders clamp the workpiece; S2, rotating the stirring head to perform friction stir welding; S3, real-time monitoring of the axial tension of the stirring head; S4. Adjust the position of the stirring head axially to maintain the axial tension of the stirring head stable.

[0015] In some embodiments, step S4 includes: A preset tension range is set. If the axial tension of the stirring head is lower than the tension range, the position of the stirring head is adjusted in the first direction until the axial tension of the stirring head is restored to the tension range. If the axial tension of the stirring head is higher than the tension range, the position of the stirring head is adjusted in the second direction until the axial tension of the stirring head is restored to the tension range, wherein the first direction and the second direction are opposite.

[0016] First, the upper and lower shoulders are clamped to press the workpiece, and then the stirring head is rotated to perform friction stir welding. The sensor is used to monitor the pulling force applied by the pulling component to the stirring head. The controller adjusts the stirring head position according to the signal fed back by the sensor to maintain the pulling force applied by the pulling component to the stirring head stable. In this way, the distance between the lower shoulder and the workpiece surface is maintained stable, and the welding quality of the workpiece is improved. BRIEF DESCRIPTION OF THE DRAWINGS

[0017] Figure 1 It is a structural schematic diagram of a retraction stirring welding host provided by an embodiment of the present invention; Figure 2 is a schematic diagram of the internal structure of a first sleeve provided in an embodiment of the present invention; FIG3 is a schematic diagram of the structure of a control component provided by an embodiment of the present invention; Explanation of the accompanying drawings: shell 100, stirring assembly 200, first sleeve 210, slide groove 211, stirring shaft 220, slide key 221, driving member 230, outer rotor 231, inner rotor 232, third bearing 240, stirring head 250, upper shoulder 251, lower shoulder 252, pulling assembly 300, pulling member 310, pulling motor 311, second sleeve 312, screw 313, second bearing 314, connecting member 320, outer ring 321, inner ring 322, first bearing 323, air gun 400, control assembly 500, sensor 510, controller 520. DETAILED DESCRIPTION

[0018] In order to make the purpose, technical solution and advantages of the present invention more clearly understood, the present invention is further described in detail below in conjunction with the accompanying drawings and embodiments. It should be understood that the specific embodiments described herein are only used to explain the present invention and are not intended to limit the present invention.

[0019] In order to solve the technical problem of how to maintain a stable distance between the lower shoulder and the workpiece surface, the present invention provides a double-shoulder welding device and a welding method, which maintains a stable pulling force applied to the stirring head, thereby maintaining a stable distance between the lower shoulder and the workpiece surface and improving the welding quality of the workpiece.

[0020] It should be noted that the double-shoulder welding device described in the present invention is used for but not limited to friction stir welding, etc. For the convenience of explanation, in the present invention, only the double-shoulder welding device applied to friction stir welding is used as an example for explanation. The principle of applying the double-shoulder welding device to other types of equipment is essentially the same as the principle applied to friction stir welding, which will not be repeated here.

[0021] See also Figure 1 , Figure 1 The structure diagram of the double-shoulder welding device in one embodiment of the present invention includes a housing 100, a stirring assembly 200 and a pulling assembly 300. The stirring assembly 200 includes a rotatable stirring head 250, and the stirring head 250 has an upper shoulder 251 and a lower shoulder 252 arranged relatively. The pulling assembly 300 is connected to the stirring head 250 in a transmission manner to adjust the position of the stirring head 250 along the axial direction. The control assembly 500 includes a sensor 510 and a controller 520. The sensor 510 is used to monitor the pulling force applied by the pulling assembly 300 to the stirring head 250. The controller 520 is respectively connected to the sensor 510 and the pulling assembly 300 for communication. The controller 520 adjusts the position of the stirring head 250 according to the signal fed back by the sensor 510 to maintain the stability of the pulling force applied by the pulling assembly 300 to the stirring head 250.

[0022] In this embodiment, the upper shoulder 251 and the lower shoulder 252 are first clamped to press the workpiece, and then the stirring head 250 is rotated to perform friction stir welding, and the sensor 510 is used to monitor the pulling force applied by the pulling component 300 to the stirring head 250. The controller 500 adjusts the position of the stirring head 250 according to the signal fed back by the sensor 510 to maintain the stability of the pulling force applied by the pulling component 300 to the stirring head 250. In this way, the distance between the lower shoulder 252 and the workpiece surface is maintained stable, thereby improving the welding quality of the workpiece.

[0023] In some embodiments, the double-shoulder welding device includes a housing 100, a stirring assembly 200 and a pulling assembly 300. The stirring assembly 200 includes a first sleeve 210, a stirring shaft 220 and a driving member 230. The first sleeve 210 is rotatably built into the housing 100, the stirring shaft 220 is coaxially built into the first sleeve 210, and the stirring shaft 220 can slide relative to the first sleeve 210 along the axial direction, and the driving member 230 drives the first sleeve 210 to rotate. The pulling assembly 300 includes a pulling member 310 and a connecting member 320. The connecting member 320 has a first connecting end and a second connecting end that can rotate relatively. The first connecting end is connected to the stirring shaft 220, and the pulling member 310 is connected to the second connecting end, and it drags the stirring shaft 220 to move along the axial direction via the connecting member 320.

[0024] In this embodiment, the stirring head is first installed on the driving end of the stirring shaft 220, and the first sleeve 210 is driven to rotate by the driving member 230, which can then drive the stirring shaft 220 to rotate, thereby driving the stirring head to rotate for friction welding. Since the first connection end and the second connection end can rotate relatively, the pulling member 310 will not hinder the rotation of the stirring shaft 220, and the pulling member 310 can be used to drag the stirring shaft 220, so that the position of the stirring shaft 220 can be finely adjusted along the axial direction to improve the welding quality.

[0025] In some embodiments, the pulling member 310 includes a pulling motor 311, a second sleeve 312 and a screw rod 313. The inner wall of the second sleeve 312 has a thread. One end of the screw rod 313 is screwed to the thread, and the other end of the screw rod 313 is fixedly connected to the connecting end. The pulling motor 311 drives the second sleeve 312 to rotate.

[0026] In this embodiment, the second sleeve 312 is driven to rotate by the pulling motor 311. Since the thread and the screw rod 313 are screwed together, as the second sleeve 312 rotates, the screw rod 313 can be driven to move axially, and then the connecting piece 320 and the stirring shaft 220 can be driven to move axially.

[0027] In some embodiments, the pulling motor 311 is a servo motor, and the sensor 510 is a torque sensor that detects the output torque of the servo motor.

[0028] In this embodiment, the torque of the pulling motor 311 can reflect the pulling force applied to the stirring head 250 , and thus the pulling force applied to the stirring head 250 can be adjusted in real time according to the torque information of the pulling motor 311 .

[0029] In some embodiments, the connecting member 320 includes an outer ring 321, an inner ring 322 and a first bearing 323, the outer ring 321 is connected to the outer ring of the first bearing 323, and is coaxially connected to the screw 313, the inner ring 322 is connected to the outer ring of the first bearing 323, and is coaxially connected to the stirring shaft 220.

[0030] In this embodiment, when the screw 313 rotates, the outer ring 321 is driven to rotate, but the torque is not transmitted to the stirring shaft 220. Similarly, when the stirring shaft 220 rotates, the inner ring 322 is driven to rotate, but the torque is not transmitted to the screw 313.

[0031] In some embodiments, the pulling member 310 further includes a second bearing 314 , an outer ring of the second bearing 314 is embedded in the inner wall of the housing 100 , and an inner ring of the second bearing 314 is sleeved on the outer circumference of the second sleeve 312 .

[0032] In this embodiment, the support of the second bearing 314 can reduce the resistance of the second sleeve 312 to rotate relative to the housing 100 .

[0033] Any implementation method that can drive the first sleeve 210 to rotate is feasible. In some embodiments, the driving member 230 includes an outer rotor 231 and an inner rotor 232, the outer rotor 231 is built into the housing 100, the inner rotor 232 is embedded in the inner rotor 232, and the inner rotor 232 is sleeved on the outer periphery of the first sleeve 210.

[0034] It should be emphasized that the outer rotor 231 and the inner rotor 232 cooperate with each other, the outer rotor 231 has a coil, and the inner rotor 232 has a permanent magnet. When the coil on the outer rotor 231 is energized, the inner rotor 232 can be driven to rotate through the electromagnetic effect, thereby driving the first sleeve 210 to rotate.

[0035] In some of the embodiments, the stirring assembly 200 further includes a third bearing 240 , an outer ring of the third bearing 240 is embedded in the inner wall of the housing 100 , and an inner ring of the third bearing 240 is sleeved on the outer periphery of the first sleeve 210 .

[0036] In this embodiment, the support of the third bearing 240 can reduce the resistance of the first sleeve 210 to rotate relative to the housing 100.

[0037] On the basis of the above embodiments, in some of the embodiments, there are two third bearings 240 , and the two third bearings 240 are respectively disposed at two ends of the first sleeve 210 .

[0038] In this embodiment, two third bearings 240 are respectively sleeved on both ends of the first sleeve 210, so as to support the first sleeve 210 more stably.

[0039] In some embodiments, a slide groove 211 is formed on the inner wall of the first sleeve 210 along the axial direction, and a sliding key 221 is formed on the outer wall of the stirring shaft 220 . The sliding key 221 is slidably disposed in the slide groove 211 .

[0040] In this embodiment, since the sliding key 221 is slidably disposed in the sliding groove 211 , the stirring shaft 220 can be prevented from rotating relative to the first sleeve 210 .

[0041] On the basis of the above embodiments, in some of the embodiments, there are multiple slide grooves 211, and the multiple slide grooves 211 are arranged along the circumference of the inner wall of the sleeve, there are multiple slide keys 221, and the multiple slide keys 221 are embedded in the multiple slide grooves 211 in a one-to-one correspondence.

[0042] In some of the embodiments, the double-shoulder welding device further includes an air gun 400 , which sprays a shielding gas toward the output end of the stirring shaft 220 .

[0043] In this embodiment, during the welding process, the air gun 400 sprays a shielding gas toward the welding point, thereby preventing the welding point from being oxidized.

[0044] In some embodiments, the lower shoulder 252 is detachably connected to the upper shoulder 251 .

[0045] On the other hand, the present invention also provides a double-shoulder welding method, which is used for the above-mentioned double-shoulder welding device, and comprises: S1. Adjust the position of the stirring head so that the upper and lower shoulders clamp the workpiece; S2, rotating the stirring head to perform friction stir welding; S3, real-time monitoring of the axial tension of the stirring head; S4. Adjust the position of the stirring head axially to maintain the axial tension of the stirring head stable.

[0046] In some embodiments, step S4 includes: A preset tension range is set. If the axial tension of the stirring head is lower than the tension range, the position of the stirring head is adjusted in the first direction until the axial tension of the stirring head is restored to the tension range. If the axial tension of the stirring head is higher than the tension range, the position of the stirring head is adjusted in the second direction until the axial tension of the stirring head is restored to the tension range, wherein the first direction and the second direction are opposite.

[0047] In order to better understand the present invention, the following Figures 1 to 3 The technical solution of the present invention is described in detail: First, the upper shoulder 251 and the lower shoulder 252 are clamped to press the workpiece, and then the stirring head 250 is rotated to perform friction stir welding, and the sensor 510 is used to monitor the pulling force applied by the pulling component 300 to the stirring head 250. The controller 500 adjusts the position of the stirring head 250 according to the signal fed back by the sensor 510 to maintain the stability of the pulling force applied by the pulling component 300 to the stirring head 250. In this way, the distance between the lower shoulder 252 and the workpiece surface is maintained stable, thereby improving the welding quality of the workpiece.

[0048] The specific implementation of the present invention described above does not constitute a limitation on the protection scope of the present invention. Any other corresponding changes and modifications made based on the technical concept of the present invention should be included in the protection scope of the claims of the present invention.

Claims

1. A double shoulder welding device, characterized in that: include: case; A stirring assembly, comprising a rotatable stirring head, wherein the stirring head has an upper shoulder and a lower shoulder arranged opposite to each other; A pulling assembly, which is transmission-connected to the stirring head to adjust the position of the stirring head along the axial direction; as well as A control component includes a sensor and a controller, wherein the sensor is used to monitor the pulling force applied by the pulling component to the stirring head, and the controller is communicatively connected to the sensor and the pulling component respectively, and adjusts the position of the stirring head according to the signal fed back by the sensor to maintain the stability of the pulling force applied by the pulling component to the stirring head.

2. The double-shoulder welding device according to claim 1, characterized in that: The stirring assembly includes a first sleeve, a stirring shaft and a driving member. The first sleeve is rotatably built into the shell, the stirring shaft is coaxially built into the first sleeve, and the stirring shaft can slide relative to the first sleeve along the axial direction. The stirring head is installed at one end of the stirring shaft, and the driving member drives the first sleeve to rotate.

3. The double-shoulder welding device according to claim 2, characterized in that: The pulling assembly includes a pulling member and a connecting member, wherein the connecting member has a first connecting end and a second connecting end that can rotate relative to each other, the first connecting end is connected to the stirring shaft, and the pulling member is connected to the second connecting end, and drags the stirring shaft to move axially via the connecting member.

4. The double-shoulder welding device according to claim 3, characterized in that: The pulling member includes a pulling motor, a second sleeve and a screw rod. The inner wall of the second sleeve has a thread. One end of the screw rod is screwed to the thread. The other end of the screw rod is fixed to the connecting end. The pulling motor drives the second sleeve to rotate.

5. The double-shoulder welding device according to claim 4, characterized in that: The pulling motor is a servo motor, and the sensor is a torque sensor which detects the output torque of the servo motor.

6. The double-shoulder welding device according to claim 2, characterized in that: The driving member includes an outer rotor and an inner rotor. The outer rotor is built into the housing, the inner rotor is embedded in the inner rotor, and the inner rotor is sleeved on the outer periphery of the first sleeve.

7. The double-shoulder welding device according to claim 2, characterized in that: A slide groove is formed on the inner wall of the first sleeve along the axial direction, and a slide key is formed on the outer wall of the stirring shaft. The slide key is slidably arranged in the slide groove.

8. The double-shoulder welding device according to claim 2, characterized in that: The lower shoulder is detachably connected to the upper shoulder.

9. A double shoulder welding method, characterized in that: It is used for the double-shoulder welding device as claimed in any one of claims 1 to 8, comprising: S1. Adjust the position of the stirring head so that the upper and lower shoulders clamp the workpiece; S2, rotating the stirring head to perform friction stir welding; S3, real-time monitoring of the axial tension of the stirring head; S4. Adjust the position of the stirring head axially to maintain the axial tension of the stirring head stable.

10. The double shoulder welding method according to claim 9, characterized in that: The step S4 comprises: A preset tension range is set. If the axial tension of the stirring head is lower than the tension range, the position of the stirring head is adjusted in the first direction until the axial tension of the stirring head is restored to the tension range. If the axial tension of the stirring head is higher than the tension range, the position of the stirring head is adjusted in the second direction until the axial tension of the stirring head is restored to the tension range, wherein the first direction and the second direction are opposite.

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