Laser welding device

Abstract

The utility model discloses a laser welding device which comprises a wire feeding gun head, a laser welding head, a power supply and a magnetic field module, the power supply, the wire feeding gun head, a welding wire and a workpiece form a direct current loop, a molten pool formed on the workpiece becomes an electrified conductor, and the magnetic field module can generate a magnetic field acting on the molten pool. During welding, current can be guided into a molten pool through a welding wire, molten metal in the molten pool is subjected to upward electromagnetic force through the action of a magnetic field, the electromagnetic force can balance the gravity of the molten metal, the metal steam pressure during welding and the like, the molten metal in the molten pool is prevented from dripping, and the quality of a formed welding seam is improved; besides the conductive function, the welding wire can also be used as filling metal, and under the action of laser energy, the welding wire is continuously melted and fills a molten pool, so that the gap adaptability in the welding process is good, and a formed welding seam is fuller.

Description

Technical Field

[0001] The utility model relates to the technical field of laser welding, in particular to a laser welding device. Background Art

[0002] Laser welding technology is widely used in aviation, aerospace, shipbuilding, automobile and other machinery manufacturing fields. With the advancement of laser manufacturing technology, laser power is getting higher and higher, and 10,000-watt high-power lasers are being used more and more in the welding field.

[0003] However, when performing high-power laser penetration welding of thick plates, the liquid metal in the molten pool is affected by its own gravity and the metal vapor pressure during welding, which may cause defects such as weld surface collapse, bottom humps, and even metal dripping at the root of the molten pool. This makes it difficult to form the weld and the welding quality of the thick plate cannot meet the requirements.

[0004] At present, the above defects can be solved by horizontal welding, but the horizontal welding method requires the plate to be erected, the plate is difficult to clamp, and the plate size is limited, resulting in the inability to use the horizontal welding method to weld the plate in many cases. Utility Model Content

[0005] In view of the above-mentioned deficiencies in the prior art, the present application provides a laser welding device that can improve the welding quality of workpieces.

[0006] This embodiment adopts the following technical solutions:

[0007] A laser welding device, comprising:

[0008] Wire feeding gun head, used to transfer welding wire to the workpiece;

[0009] A laser welding head is used to emit laser light and irradiate the workpiece, so that the workpiece and welding wire melt and form a molten pool;

[0010] A power source forms a DC circuit with the wire feed gun head, the welding wire and the workpiece, so that the molten pool becomes a live conductor; and

[0011] The magnetic field module can generate a magnetic field acting on the molten pool, so that the molten metal in the molten pool is subjected to an upward Ampere force.

[0012] Furthermore, in the laser welding device, the magnetic field module includes a bracket and a magnet, the bracket moves with the laser welding head, the magnet is arranged on the bracket, and the N pole and S pole of the magnet are relatively arranged on both sides of the molten pool.

[0013] Furthermore, in the laser welding device, the height of the magnet from the surface of the workpiece is 3 to 20 mm, and the distance between the N pole and the S pole of the magnet is 5 to 20 mm.

[0014] Furthermore, in the laser welding device, the magnetic field module further includes one or more support rods, one end of the support rod is connected to the laser welding head, and the other end of the support rod is connected to the bracket.

[0015] Furthermore, in the laser welding device, the support rod is an elastic support rod so as to elastically press the bracket against the workpiece.

[0016] Furthermore, in the laser welding device, the magnetic field module further includes one or more rollers, and the rollers are arranged at the bottom of the bracket, and the bracket is rollingly connected to the workpiece through the rollers.

[0017] Furthermore, the laser welding device also includes a driving mechanism and a connecting plate, the laser welding head is connected to the driving end of the driving mechanism through the connecting plate, the support rod is arranged on the connecting plate, and the wire feeding gun head is arranged on the connecting plate or the laser welding head.

[0018] Furthermore, in the laser welding device, the wire feeding gun head follows the laser welding head, and the welding wire is transmitted to the front of the moving path of the laser and can enter the molten pool.

[0019] Furthermore, the laser welding device also includes an airflow module for blowing protective gas into the molten pool, a gap is formed between the N pole and the S pole of the magnet, and the airflow module is arranged on the bracket and located in the gap.

[0020] Furthermore, in the laser welding device, the airflow module includes a module body and a drag hood, the module body is provided with a first air inlet, a second air inlet, a third air inlet, a side blowing air port and a transverse blowing air port, the drag hood is arranged at the bottom of the module body and is connected to the first air inlet, the surface of the drag hood forms an air outlet surface aligned with the high-temperature weld, the side blowing air port is connected to the second air inlet to blow air to the molten pool, and the transverse blowing air port is connected to the third air inlet to blow air above the molten pool.

[0021] Compared with the prior art, the laser welding device provided in the present application can introduce current into the molten pool through the welding wire, and through the action of the magnetic field, the molten metal in the molten pool generates an upward electromagnetic force, which can balance the self-gravity of the molten metal and the metal vapor pressure during welding, thereby avoiding dripping of molten metal in the molten pool and improving the quality of the weld after formation; and, in addition to its conductive function, the welding wire can also be used as filler metal. Under the action of laser energy, the welding wire continuously melts and fills the molten pool, so that the welding process has good gap adaptability and the weld after formation is fuller. BRIEF DESCRIPTION OF THE DRAWINGS

[0022] Figure 1 This is a schematic diagram of the overall structure of a specific embodiment of the laser welding device provided in this application.

[0023] Figure 2 for Figure 1 Schematic diagram of electromagnetic force generation in the workpiece molten pool in the laser welding device shown.

[0024] Figure 3 for Figure 1 A partial enlarged view of the laser welding device shown.

[0025] Figure 4 for Figure 1 Schematic diagram of the installation of the airflow module in the laser welding device shown.

[0026] Among them, 10, wire feeding gun head; 20, laser welding head; 21, laser beam; 30, power supply; 40, magnetic field module; 41, bracket; 42, magnet; 43, support rod; 44, roller; 50, wire; 60, connecting plate; 70, air flow module; 71, air inlet; 72, side blowing air port; 73, horizontal blowing air port; 100, workpiece; 110, molten pool. DETAILED DESCRIPTION

[0027] In order to make the purpose, technical solution and effect of the present application clearer and more specific, the present application is further described in detail with reference to the accompanying drawings and examples. It should be understood that the specific embodiments described herein are only used to explain the present application and are not used to limit the present application. Without further description, the elements, structures and features in one embodiment can also be beneficially combined with other embodiments.

[0028] It should be noted that when a metastructure is referred to as being "fixed to" or "set on" another metastructure, it may be directly on the other metastructure or indirectly on the other metastructure. In addition, the terms "first" and "second" are used for descriptive purposes only and cannot be understood as indicating or implying relative importance or implicitly indicating the number of the indicated technical features.

[0029] The orientation or positional relationship indicated by terms such as "length", "width", "up", "down", "front", "back", "left", "right", "vertical", "horizontal", "top", "bottom", "inside" and "outside" are based on the orientation or positional relationship shown in the drawings and are only for the convenience of describing the present application and simplifying the description, and do not indicate or imply that the device or element structure referred to must have a specific orientation, be constructed and operate in a specific orientation.

[0030] See also Figure 1The laser welding device provided in the present application includes a wire feeding gun head 10, a laser welding head 20, a DC power supply 30 and a magnetic field module 40. The wire feeding gun head 10 is used to transmit the welding wire to the workpiece 100 to be processed. The laser welding head 20 is used to emit a laser and melt the welding wire and the workpiece 100 by the laser to form a liquid metal part with a certain shape on the workpiece 100, that is, a molten pool 110.

[0031] The workpiece 100 may be a metal plate, a metal component, etc. In the molten pool generated by the workpiece 100, the melted and mixed workpiece and welding wire will flow to the tail of the molten pool 110, and form a weld after cooling. In this process, the size, shape and depth of the molten pool 110 will affect the strength, density and appearance of the weld, and thus determine the quality of the weld formed on the workpiece 100.

[0032] The power source 30 is used to provide direct current, and the power source 30 forms a direct current loop with the wire feeding gun head 10, the welding wire and the workpiece 100, so that the molten pool on the workpiece 100 becomes a charged conductor.

[0033] In some embodiments, the positive pole of the DC power supply 30 can be connected to the wire feeding gun head 10 through a conductor 50, and the wire feeding gun head 10 then transmits the welding wire in contact with it to the molten pool of the workpiece 100, and the workpiece 100 is connected to the negative pole of the DC power supply 30 through another conductor 50. Therefore, the power supply 30, the wire feeding gun head 10, the welding wire and the workpiece 100 form a complete circuit, so that a DC current passes through the molten pool of the workpiece 100.

[0034] Alternatively, according to actual needs, the connection objects of the positive and negative electrodes of the DC power supply 30 can be adjusted, such as the connection objects can be interchanged to change the direction of the current passing through the molten pool.

[0035] The magnetic field module 40 is used to generate a magnetic field and act on the molten pool during welding, so that the molten metal in the molten pool is subjected to an upward electromagnetic force (or Ampere force).

[0036] The electromagnetic force is the force exerted on the current-carrying conductor 50 in the magnetic field. According to the left-hand rule, the thumb is perpendicular to the other four fingers and in the same plane, the magnetic flux lines are passed through the palm, the four fingers point in the direction of the current, and the direction of the thumb is the direction of the electromagnetic force. Therefore, by adjusting the magnetic field direction of the magnetic field module 40 and the current direction of the DC circuit in the molten pool, the molten metal in the molten pool can obtain an upward electromagnetic force.

[0037] In some embodiments, Figure 2As shown in the figure, when the magnetic field is from left to right and the direction of the current D applied to the molten pool 110 is from inside the paper to outside the paper, according to the left-hand rule, the molten metal in the molten pool 110 will generate an upward electromagnetic force F. During the welding process, the electromagnetic force can balance the self-gravity of the molten metal and the metal vapor pressure during welding, thereby preventing the molten metal in the molten pool 110 from dripping and improving the quality of the weld after forming.

[0038] Furthermore, by introducing current into the molten pool 110 through the welding wire, a higher current density can be obtained in the molten pool 110 , and correspondingly, the molten metal in the molten pool 110 is more likely to obtain a larger Ampere force, thereby more effectively controlling the dripping of the molten metal in the molten pool 110 .

[0039] In some embodiments, the wire feed gun head 10 can follow the laser welding head 20 and ensure that the welding wire is continuously transmitted by the wire feed gun head 10 to the front of the moving path of the laser welding head 20 emitting the laser.

[0040] In addition to the conductive function, the welding wire can also be used as a filler metal. Under the action of the laser energy, the welding wire continuously melts and fills the molten pool 110, making the formed weld more full. Even if there is a certain assembly gap at the welding position, a weld with convex sides can be obtained, making the gap adaptability of the welding process better.

[0041] Furthermore, the wire feeding gun head 10 may include a housing and a wire guide nozzle, the wire guide nozzle is arranged at the end of the housing, and the housing and the wire guide nozzle are both made of metal, and the housing can be fixed on the laser welding head 20 to achieve follow-up with the laser welding head 20. The welding wire is transmitted to the workpiece 100 through the wire guide nozzle in the housing, and the power supply 30 can be connected to the housing through the wire 50, so that the current output by the power supply 30 is sequentially conducted to the molten pool 110 through the housing, the wire guide nozzle and the welding wire.

[0042] To carry higher current, preferably use thicker diameter welding wire. Meanwhile, to better carry out welding wire melting and penetration welding of thicker workpieces, a high-power laser welding head 20 that can withstand higher power can be adopted.

[0043] Furthermore, the power source 30 may be selected as a high current DC generator to generate a relatively large current, such as 500A or more, during welding, thereby obtaining a relatively large ampere force.

[0044] See also Figure 3 In some embodiments, the magnetic field module 40 may include a bracket 41 and a magnet 42 , the bracket 41 moves with the laser welding head 20 , the magnet 42 is disposed on the bracket 41 , and the N pole and S pole of the magnet 42 are disposed on both sides of the molten pool 110 opposite to each other.

[0045] At this time, the laser beam 21 generated by the laser welding head 20 will pass through the magnet 42 to form a molten pool 110 on the workpiece 100, and the magnetic field generated by the magnet 42 will pass through the molten pool 110 horizontally. At the same time, the current direction in the molten pool 110 is set perpendicular to the magnetic field direction, so that the molten metal in the molten pool 110 generates an upward electromagnetic force.

[0046] In some embodiments, the positive electrode of the power supply 30 can be connected to the wire feeding gun head 10 through the wire 50, and the negative wire 50 is connected to the workpiece 100, and the connection position is the starting end of the weld, or a place close to the starting end of the weld, so that the current passes through the molten pool 110 and the current direction D is opposite to the welding direction.

[0047] At the same time, the N pole of the magnet 42 is arranged on the left side along the welding direction, and the S pole is arranged on the right side along the welding direction, and the magnetic field lines formed by the magnet 42 are in the direction of the N pole pointing to the S pole, and horizontally pass through the molten pool 110. According to the left-hand rule, the molten metal in the molten pool 110 generates an upward electromagnetic force F.

[0048] The magnet 42 may be a permanent magnet or an electromagnet. When the magnet 42 is an electromagnet, the strength of the magnetic field of the electromagnet may be changed by changing the magnitude of the current of the electromagnet, thereby changing the strength of the magnetic field passing through the molten pool 110 to adjust the magnitude of the electromagnetic force.

[0049] Furthermore, the height of the magnet 42 from the surface of the workpiece 100 can be set to 3-20 mm, and the distance between the N pole and the S pole of the magnet 42 can be set to 5-20 mm.

[0050] The smaller the height of the magnet 42 from the surface of the workpiece 100 and the smaller the distance between the N pole and the S pole of the magnet 42, the higher the magnetic field strength passing through the molten pool 110, and the greater Ampere force can be obtained. However, due to the small processing space and the greater hardware interference, the above height range and distance range can take into account both higher magnetic field strength and smaller hardware interference to achieve a better welding effect.

[0051] In some embodiments, the magnetic field module 40 further includes one or more support rods 43 , one end of the support rod 43 is connected to the laser welding head 20 , and the other end of the support rod 43 is connected to the bracket 41 .

[0052] The support rod 43 is used to connect the bracket 41 and the laser welding head 20 to each other, so that the magnet 42 moves with the laser welding head 20 to maintain the relative position between the magnetic field of the magnet 42 and the newly generated molten pool 110 on the workpiece 100. Specifically, the magnet 42 can be located below the laser welding head 20, and the laser generated by the laser welding head 20 passes between the N pole and the S pole of the magnet 42.

[0053] Furthermore, the support rod 43 can be an elastic support rod to elastically press the bracket 41 onto the workpiece 100, so that the height of the magnetic field from the surface of the workpiece 100 remains unchanged, thereby keeping the magnetic field strength passing through the molten pool 110 unchanged, ensuring that the molten metal generates a stable upward electromagnetic force.

[0054] For example, the support rod 43 may be composed of two or more rods, which are slidably connected to each other and supported by springs, so that the support rod 43 can elastically expand and contract along its own axis, thereby elastically pressing the bracket 41 against the workpiece 100 .

[0055] The support rod 43 may also be designed as an S-shaped, Z-shaped or other bending structure to elastically press the bracket 41 onto the workpiece 100. Alternatively, the support rod 43 may also adopt other common elastic structures, which is not limited in the present application.

[0056] In some embodiments, the magnetic field module 40 further includes one or more rollers 44 . The rollers 44 are disposed at the bottom of the bracket 41 . The bracket 41 is rollingly connected to the workpiece 100 via the rollers 44 .

[0057] The function of the roller 44 is to reduce the friction between the bracket 41 and the workpiece 100, so that when the bracket 41 moves with the laser welding head 20, the normal movement of the laser welding head 20 can be avoided due to excessive friction between the bracket 41 and the workpiece 100, and at the same time, greater wear on the bracket 41 and the workpiece 100 can be avoided.

[0058] In some embodiments, the laser welding device may also include a driving mechanism (not shown) and a connecting plate 60, the laser welding head 20 is connected to the driving end of the driving mechanism through the connecting plate 60, the support rod 43 is arranged on the connecting plate 60, and the wire feeding gun head 10 is arranged on the connecting plate 60 or the laser welding head 20.

[0059] The driving mechanism is used to drive the laser welding head 20 to move so that the laser welding head 20 can weld the workpiece 100 according to a preset welding trajectory. The connecting plate 60 plays a connecting and mounting role so that the magnetic field module 40 and the wire feeding gun head 10 can move with the laser welding head 20 to reduce the driving cost.

[0060] Also, see Figure 3 and Figure 4 The laser welding device may also include an airflow module 70 for blowing a protective gas into the molten pool 110 to isolate the molten pool 110 from the outside atmosphere and prevent oxygen and other harmful gases from contacting the molten pool 110, thereby slowing down or preventing the occurrence of an oxidation reaction and maintaining the quality of the formed weld.

[0061] The airflow module 70 can be arranged on the bracket 41 and move with the magnetic field module 40. In addition, the magnet can adopt a U-shaped structure or other similar structures, so that a gap is formed between the N pole and the S pole of the magnet, and the airflow module 70 can be installed in the gap, effectively utilizing the installation space here, making the entire laser welding device structure more compact.

[0062] In some embodiments, the airflow module 70 includes a module body and a hood (not shown), the module body is provided with a plurality of air inlets 71, such as a first air inlet, a second air inlet and a third air inlet, the hood is arranged at the bottom of the module body, and the surface of the hood forms an air outlet surface aligned with the high-temperature weld.

[0063] The hood is connected to the first air inlet, and the gas introduced is welding shielding gas. The air outlet surface of the hood can be made of porous medium material, which has a certain air permeability and can withstand a certain gas pressure. After the welding shielding gas is introduced from the first air inlet, it is ejected from the air outlet surface of the hood to continue to provide anti-oxidation protection for the solidified weld that has left the molten pool 110 but is still in a high temperature state, so as to improve the quality of the weld.

[0064] The module body may also be provided with a side blowing port 72 connected to the second air inlet, and the side blowing port 72 forms a certain incident angle with the molten pool 110. During welding, after the welding shielding gas is introduced from the second air inlet, the side blowing port 72 may blow out shielding gas toward the molten pool 110, which may, on the one hand, blow away part of the plasma generated in the molten pool 110 to improve the uniformity and smoothness of the weld formation, and, on the other hand, may provide anti-oxidation protection for the molten pool 110.

[0065] The module body can also be provided with a transverse air port 73 connected to the third air inlet. The gas introduced into the third air inlet is compressed gas with a relatively high pressure, so that the transverse air port 73 blows out high-flow gas above the molten pool 110, thereby suppressing the plasma and smoke generated by laser welding, reducing interference and shielding of the incident laser, and improving welding stability and welding depth; at the same time, the high-flow gas blown out by the transverse air port 73 can shield the spatter generated during the welding process above the molten pool 110, thereby protecting the lens of the laser welding head 20.

[0066] Specifically, the height of the module body from the surface of the workpiece 100 can be set to 5-15 mm to avoid the airflow module 70 interfering with the welding process and ensure the strength of the airflow. In addition, according to the actual application, each airflow can be opened separately or in combination.

[0067] It is understandable that those skilled in the art can make equivalent substitutions or changes based on the technical solution and application concept of the present application, and all these changes or substitutions should fall within the protection scope of the claims attached to the present application.

Claims

1. A laser welding device, characterized in that: include: Wire feeding gun head, used to transfer welding wire to the workpiece; A laser welding head is used to emit laser light and irradiate the workpiece, so that the workpiece and welding wire melt and form a molten pool; A power source forms a DC circuit with the wire feeding gun head, the welding wire and the workpiece, so that the molten pool becomes a live conductor; as well as The magnetic field module can generate a magnetic field acting on the molten pool, so that the molten metal in the molten pool is subjected to an upward Ampere force.

2. The laser welding device according to claim 1, characterized in that: The magnetic field module comprises a bracket and a magnet. The bracket moves with the laser welding head. The magnet is arranged on the bracket, and the N pole and S pole of the magnet are arranged oppositely on two sides of the molten pool.

3. The laser welding device according to claim 2, characterized in that: The height of the magnet from the surface of the workpiece is 3 to 20 mm, and the distance between the N pole and the S pole of the magnet is 5 to 20 mm.

4. The laser welding device according to claim 2, characterized in that: The magnetic field module further includes one or more support rods, one end of each support rod is connected to the laser welding head, and the other end of each support rod is connected to the bracket.

5. The laser welding device according to claim 4, characterized in that: The support rod is an elastic support rod so as to elastically press the bracket against the workpiece.

6. The laser welding device according to claim 4, characterized in that: The magnetic field module further includes one or more rollers, wherein the rollers are arranged at the bottom of the bracket, and the bracket is rollingly connected to the workpiece via the rollers.

7. The laser welding device according to claim 4, characterized in that: It also includes a driving mechanism and a connecting plate, the laser welding head is connected to the driving end of the driving mechanism through the connecting plate, the support rod is arranged on the connecting plate, and the wire feeding gun head is arranged on the connecting plate or the laser welding head.

8. The laser welding device according to claim 2, characterized in that: The wire feeding gun head follows the laser welding head, and the welding wire is transmitted to the front of the moving path of the laser and can enter the molten pool.

9. The laser welding device according to any one of claims 2 to 8, characterized in that: It also includes an airflow module for blowing protective gas into the molten pool. A gap is formed between the N pole and the S pole of the magnet. The airflow module is arranged on the bracket and located in the gap.

10. The laser welding device according to claim 9, characterized in that: The airflow module includes a module body and a drag hood, the module body is provided with a first air inlet, a second air inlet, a third air inlet, a side blowing air port and a transverse blowing air port, the drag hood is arranged at the bottom of the module body and is connected to the first air inlet, the surface of the drag hood forms an air outlet surface aligned with the high-temperature weld, the side blowing air port is connected to the second air inlet to blow air to the molten pool, and the transverse blowing air port is connected to the third air inlet to blow air above the molten pool.

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