WO2021065063A1

WO2021065063A1 - Welding device and welding method

Info

Publication number: WO2021065063A1
Application number: PCT/JP2020/018458
Authority: WO
Inventors: 裕企雄佐藤; 督生川崎; 郁馬肥後; 光彦渡邉
Original assignee: 三菱電機株式会社
Priority date: 2019-10-03
Filing date: 2020-05-01
Publication date: 2021-04-08

Abstract

This welding device is provided with a laser emitting unit (10), and a gas ejecting unit (20). The laser emitting unit (10) emits a laser (L) to a condensing point (C). The gas ejecting unit (20) ejects a gas (G) toward a peripheral portion (P1) of the condensing point (C). The laser emitting unit (10) radiates the laser (L) at members (R1, R2) being welded, while moving relative to the members (R1, R2) being welded. The gas ejecting unit (20) ejects the gas (G) flowing in a direction opposite to the direction in which the condensing point (C) moves along the surface of the members (R1, R2) being welded.

Description

Welding equipment and welding method

This disclosure relates to welding equipment and welding methods.

Design panel members reinforced with reinforcing members are used for the elevator landing doors, car doors, and car room walls. The design panel and the reinforcing member were sometimes joined by spot welding or an adhesive. Spot welding requires the welding strain to be corrected with a grinder. Adhesives are excellent in finished condition, but inferior to spot welding in terms of fire resistance.

Since laser welding is excellent in obtaining a narrow bead and a deep penetration shape due to the steep energy density distribution of the laser, high-speed and precise heat input control is performed even for thin steel plates made of steel plates and materials including stainless steel. Deep penetration welding is possible, and the heat effect is small. It also has the advantage of being more efficient because the equipment can be easily automated.

When using laser welding technology, a shield gas, which is an assist gas containing nitrogen and argon, is used to prevent a decrease in strength due to corrosion of the welded part due to oxidation. Patent Document 1 discloses an example in which 30 l / min argon gas is used as a shield gas as a laser welding condition. Further, since fume and spatter generated from a portion melted by the heat input of the laser beam cause a decrease in welding strength, a method for suppressing and removing the fume and spatter is required for precision welding.

JP-A-2007-000888

Since the shield gas is used for the purpose of removing oxygen from the welded part, it is used by spraying it toward the vicinity of the laser irradiation part. If the flow rate of the shield gas is increased, oxygen in the atmosphere may be involved in the molten portion, which may have an adverse effect, which may lead to poor welding quality, and it is not easy to obtain high-quality welding. In addition, the inert gas is expensive.

The present disclosure has been made in view of the above-mentioned actual conditions, and an object of the present disclosure is to provide a welding apparatus and a welding method that enable high-quality welding by an inexpensive method even in high-precision welding.

In order to achieve the above object, the welding apparatus according to the present disclosure includes a laser emitting unit that emits a laser to a condensing point and a gas injection unit that injects gas toward a peripheral portion of the condensing point. The emitting portion irradiates the welding target member with a laser while moving relative to the welding target member, and the gas injection portion flows on the surface of the condensing point in the welding target member in a direction opposite to the moving direction. Inject gas.

According to the present disclosure, high-quality welding can be made possible by an inexpensive method even in high-precision welding.

The figure which shows the welding apparatus which concerns on 1st Embodiment The block diagram which shows the welding apparatus which concerns on 1st Embodiment Partial sectional view which shows the laser emission part and the gas injection part of the welding apparatus which concerns on 1st Embodiment. The figure which shows the nozzle of the welding method which concerns on 1st Embodiment AA cross-sectional view of FIG. BB sectional view of FIG. The figure which shows the moving direction of the laser emitting part and the gas injection part and the direction of a gas injection part which concerns on 1st Embodiment. The figure which shows the moving direction of the laser emitting part and the gas injection part and the direction of a gas injection part which concerns on 1st Embodiment. The figure which shows the moving direction of the laser emitting part and the gas injection part and the direction of a gas injection part which concerns on 1st Embodiment. The figure which shows the moving direction of the laser emitting part and the gas injection part and the direction of a gas injection part which concerns on 1st Embodiment. The figure which shows the 1st welding target member and the 2nd welding target member which concerns on 1st Embodiment. Flow chart showing welding process according to the first embodiment Sectional drawing explaining the welding method which concerns on 1st Embodiment Sectional drawing explaining the welding method which concerns on 1st Embodiment Sectional drawing explaining welding method which concerns on comparative example Sectional drawing which shows the injection port of the gas injection part which concerns on 1st modification Sectional drawing which shows the injection port of the gas injection part which concerns on 1st modification Sectional drawing which shows the injection port of the gas injection part which concerns on 1st modification Sectional drawing explaining the welding method which concerns on 1st modification Partial sectional view showing the laser emitting part and the gas injection part of the welding apparatus which concerns on 2nd Embodiment The figure which shows the coaxial nozzle of the welding method which concerns on 2nd Embodiment CC sectional view of FIG. DD sectional view of FIG. Sectional drawing explaining the welding method which concerns on 2nd Embodiment Sectional drawing which shows the injection port of the gas injection part which concerns on 2nd modification Sectional drawing which shows the injection port of the gas injection part which concerns on 2nd modification Sectional drawing which shows the injection port of the gas injection part which concerns on 2nd modification

Hereinafter, the welding apparatus and welding method according to the embodiment of the present disclosure will be described.

(First Embodiment)
As shown in FIGS. 1 and 2, the welding apparatus 100 according to the first embodiment includes a laser emitting unit 10 that emits a laser L, a gas injection unit 20 that injects a gas G, a laser emitting unit 10 and a laser emitting unit 10. A robot unit 30 that moves the gas injection unit 20, a surface plate 40 on which a first welding target member R1 and a second welding target member R2 that are overlapped are placed, a laser emitting unit 10, a gas injection unit 20, and a robot. A control unit 50 that controls the unit 30 is provided. The first welding target member R1 is a metal reinforcing member having a plate-shaped portion. The second welding target member R2 is a metal design panel used for a landing door, a car door, or a car room wall of an elevator facility. The back surface of the surface of the second welding target member R2 that comes into contact with the first welding target member R1 is a design surface DS that appears in the appearance.

To facilitate understanding, set xyz coordinates that are orthogonal to each other and refer to them as appropriate. The direction in which the laser emitting unit 10 moves is set to the x direction, the direction in which the laser emitting unit 10 irradiates the laser L is set to the z direction, and the directions perpendicular to the x direction and the z direction are set to the y direction. The xy plane is a plane parallel to the plane irradiated with the laser in the first member R1 to be welded.

The laser emitting unit 10 irradiates the first member R1 to be welded with the laser L, and is transmitted to a power source, a laser oscillator, and a mirror or an optical fiber that transmits the laser L oscillated by the laser oscillator. A fiber or disc laser comprising an optical system including a condenser lens that condenses the laser L. By oscillating the laser by these methods, the laser can be easily irradiated perpendicularly to the first welding target member R1. The focusing diameter of the laser L emitted from the laser emitting unit 10 is 0.1 mm or more and 0.2 mm or less. The position of the condensing point C in the z direction is adjusted by the robot unit 30 to a position where the robot unit 30 just focuses on the surface of the first welding target member R1 facing the laser emitting unit 10. The output of the laser L of the laser emitting unit 10 is controlled by the control unit 50 to an output that does not cause a welding trace on the design surface DS of the second welding target member R2. For example, when laminating thin steel plates having a thickness of 1.5 mm, the bead width is preferably 0.5 mm or more and 1.0 mm or less, and the penetration depth of the second welding target member R2 is 0.1 mm or more and 0.3 mm. The output of the laser L is controlled below. When the thickness of the thin steel sheet becomes large, the laser output may be adjusted so that the light collecting diameter is appropriately increased to increase the bead width and the penetration depth. The output of the laser L is preferably 100 W or more and 10 kW or less, and more preferably 500 W or more and 2 kW or less.

As shown in FIGS. 3 and 4, the gas injection unit 20 injects the gas G, which is compressed air, into the peripheral portion P1 of the condensing point C of the laser L. The gas injection unit 20 is injected with a nozzle 21 having a flow path 22, a regulator 23 that controls the flow rate of the gas G, a rotating unit 24 that rotates the flow path 22 around a path through which the laser passes, and a gas G. It has an injection port 25, an internal space 26 through which the laser L passes, and a helicoid portion 27 that moves the nozzle 21 in the z direction.

The nozzle 21 has a semi-circular truncated cone shape centered on the central axis AX, and has a hollow tapered shape that shrinks in diameter as it advances in the z direction. The central axis AX is a path through which the laser L passes.

The flow path 22 is a gas flow path that is arranged at a position away from the central axis AX and surrounds the central axis AX, and is a path that approaches the central axis AX along the laser L from the laser emitting portion 10 toward the focusing point C. Is formed in. The gas G flowing through the flow path 22 is injected from the injection port 25. The flow path 22 and the injection port 25 are formed in a region in the x direction from the central axis AX in the state shown in FIG. The angle θ formed by the flow path 22 and the z-axis is preferably 3 ° or more and 30 ° or less, and more preferably 5 ° or more and 20 ° or less. The extension line of the flow path 22 intersects the peripheral portion P1 of the condensing point C where the laser L is irradiated to the first welding target member R1. The peripheral portion P1 is a position deviated from the focusing point C in the x direction. When viewed in the z direction, the inlet portion of the flow path 22 has a shape along a semicircular arc surrounding the central axis AX, as shown in FIG. 5A. Further, when viewed in the z direction, the injection port 25 has a slit-like shape along a semicircular arc surrounding the central axis AX, as shown in FIG. 5B. The diameter r1 of the inlet portion of the flow path 22 is larger than the diameter r2 of the injection port 25, and preferably the diameter r1 with respect to the diameter r2 is 1.5 times or more and 3 times or less. The diameter r2 is preferably 10 mm or more and 30 mm or less. The gap w1 of the injection port 25 is preferably 1 mm or more and 2 mm or less.

The regulator 23 shown in FIG. 3 is controlled by the control unit 50 to adjust the flow rate of the gas G flowing through the flow path 22. When irradiating the laser L from the laser emitting unit 10, the control to open the regulator 23 is executed. As a result, the gas G is injected from the injection port 25. The flow rate of the gas G injected from the injection port 25 is at least a flow rate at which fume can be removed, which is larger than the flow rate when the shield gas is flowed, preferably 50 l / min or more and 200 l / min or less, and more preferably. It is 70 l / min or more and 150 l / min or less. When spot welding, the helicoid unit 27 is controlled by the control unit 50 to move the nozzle 21 in the z direction. As a result, the injection port 25 of the gas injection unit 20 approaches the first and second welding target members R1 and R2.

The rotating unit 24 has a servomotor or a stepping motor that rotates the flow path 22 and the injection port 25 around the central axis AX, and is controlled by the control unit 50. When irradiating the first and second welding target members R1 and R2 with a laser while moving in the x direction relative to the first and second welding target members R1 and R2, the central portion CP of the injection port 25 Is arranged at a position separated from the central axis AX in the x direction as shown in FIG. 6A. The positions of the flow path 22 and the injection port 25 in this case are set as reference positions. When the gas G is flowed through the flow path 22 with the injection port 25 arranged at the reference position, the gas G is sprayed on the peripheral portion P1 and is in the direction of stroking the surface of the condensing point C of the laser L. Flow in the direction. Therefore, a stable airflow AF that does not disturb the molten pool is generated. When irradiating the first and second welding target members R1 and R2 with the laser L while moving in the −x direction relative to the first and second welding target members R1 and R2, the rotating portion 24 As shown in FIG. 6B, the injection port 25 is rotated by 180 ° from the reference position about the central axis AX, and the central CP of the injection port 25 is arranged at a position separated from the central axis AX in the −x direction. Further, when irradiating the welding target members R1 and R2 with a laser while moving in the y direction relative to the first and second welding target members R1 and R2, as shown in FIG. 6C, the central axis AX is set. The flow path 22 is rotated 90 ° from the reference position at the center. Further, when irradiating the first and second welding target members R1 and R2 with a laser while moving in a direction inclined by 45 ° from the x direction relative to the first and second welding target members R1 and R2. , As shown in FIG. 6D, the flow path 22 is rotated by 45 ° from the reference position about the central axis AX.

The robot unit 30 shown in FIG. 1 has a rail 31 extending in the x direction, a first drive unit that drives in the x direction along the rail 31, and a second drive unit that drives in the z direction, and is a control unit. Under the control of 50, the laser emitting unit 10 and the gas injection unit 20 are moved in the x direction or the −x direction along the rail 31. Further, the robot unit 30 moves the laser emitting unit 10 and the gas injection unit 20 in the z direction according to the thickness and shape of the first and second welding target members R1 and R2, and the light collecting point C in the z direction. Is adjusted to the surface of the first welding target member R1 facing the laser emitting portion 10.

The surface plate 40 has a surface 41 parallel to the xy plane, and mounts the first and second welding target members R1 and R2. The first and second welding target members R1 and R2 are pressed and fixed to the surface plate 40 by a jig or a roller. When a roller is used, the unwelded portions of the first and second welding target members R1 and R2 are pressed against the surface plate 40 with a force of 10 kgf or more and 30 kgf or less.

The control unit 50 shown in FIG. 2 includes a CPU (Central Processing Unit) 51 for executing a program, a ROM (Read Only Memory) 52 for storing the program, and a RAM (Random Access) used as a work area for executing the program. By executing the program stored in the ROM 52 having the Memory) 53, the output of the laser of the laser emitting unit 10, the flow rate of the gas G injected from the gas injection unit 20, and the robot unit 30 are controlled.

Specifically, the control unit 50 controls the laser emission unit 10, the gas injection unit 20, and the robot unit 30 based on the materials, shapes, and welding positions of the first and second welding target members R1 and R2. The control unit 50 measures the thicknesses of the first and second welding target members R1 and R2 and data indicating the materials of the first and second welding target members R1 and R2 in order to further improve the welding quality. Is acquired, and the output is controlled to irradiate the laser L suitable for the thickness and material. Further, the control unit 50 controls the robot unit 30 to move the laser emitting unit 10 and the gas injection unit 20 in the x direction or the −x direction. When the robot unit 30 emits the laser L from the laser emitting unit 10 while moving in the x direction, the control unit 50 arranges the flow path 22 at a reference position. On the other hand, when irradiating the laser L while moving in the −x direction, the rotating portion 24 is controlled and the flow path 22 is arranged at a position rotated by 180 ° from the reference position. Further, when irradiating the laser L without moving, the helicoid portion 27 is controlled to move the nozzle 21 in the z direction.

Next, the welding process executed by the welding device 100 will be described with respect to an example in which the welding device 100 having the above configuration welds the first welding target member R1 and the second welding target member R2.

As shown in FIG. 7, the first welding target member R1 is a reinforcing member having a hat-shaped cross-sectional shape, and is a steel plate or stainless steel mainly composed of iron. The thickness of the first welding target member R1 has a thickness that secures the strength used as the reinforcing member.

The second welding target member R2 is a steel plate or stainless steel mainly made of iron, like the first welding target member R1. The second welding target member R2 is a design panel used for a landing door, a car door, or a car chamber wall of an elevator facility, and is in contact with the first welding target member R1 in the second welding target member R2. The back surface of the surface to be welded is the design surface DS that appears in the exterior.

The first welding target member R1 and the second welding target member R2 are overlapped by an operator and arranged so as to be aligned with the surface plate 40 of the welding apparatus 100.

The welding device 100 starts the welding process shown in FIG. 8 in response to an instruction from the user to start the process. Hereinafter, the welding process executed by the welding apparatus 100 will be described with reference to a flowchart. In the initial state, the flow path 22 and the injection port 25 are arranged at reference positions.

When the welding process is started, the control unit 50 of the welding apparatus 100 acquires welding data indicating the materials and shapes of the first and second welding target members R1 and R2, and the planned welding positions T1 and T2 (step S101). ). The acquired welding data is stored in the RAM 53. The welding data includes data indicating whether or not to irradiate the laser while moving, data indicating whether to irradiate the laser L while moving in the x direction or −x direction, and data indicating the moving distance. In this example, the planned welding position T1 is moved in the x direction and the planned welding position T2 is moved in the −x direction while being welded. First, the control unit 50 determines whether or not to irradiate the laser L while moving based on the welding data for welding the scheduled welding position T1 (step S102). In this example, it is determined that the laser L is irradiated while moving (step S102; Yes), and it is determined whether or not to irradiate the laser L while moving in the x direction (step S103).

In this example, it is determined that the laser L is irradiated while moving in the x direction (step S103; Yes), and the control unit 50 executes control to open the regulator 23 shown in FIG. 3 (step S104). In this state, the flow path 22 and the injection port 25 are arranged at the reference positions, so that the gas G injected from the injection port 25 is sprayed onto the peripheral portion P1 and the surface of the focusing point C of the laser L. Since it flows in the −x direction, which is the direction of stroking, a stable airflow AF that does not disturb the molten pool is generated. Next, the control unit 50 controls the robot unit 30 to start moving the laser emitting unit 10 and the gas injection unit 20 in the x direction (step S105). Next, while moving the laser emitting unit 10 and the gas injection unit 20 in the x direction, the control unit 50 controls the laser emitting unit 10 to transfer the laser L to the first and second welding target members R1 and R2. Irradiate (step S112). The fume and spatter generated from the melted portion due to the heat input of the laser L are blown off by the airflow AF of the gas G in the −x direction opposite to the x direction, which is the moving direction, and are removed from the focusing point C of the laser L. .. Further, since the fume and spatter are blown to the upper part of the welded region that has already been welded, the fume and spatter are less in the upper part of the unwelded region to be welded. When the laser emitting unit 10 and the gas injection unit 20 move the moving distance included in the welding data, the control unit 50 controls the laser emitting unit 10 to stop the irradiation of the laser L and end the welding process. As a result, the planned welding positions T1 of the first and second welding target members R1 and R2 are welded, and a design panel to which the reinforcing member is welded is obtained. Next, it is determined whether or not welding is completed (step S113). Here, since the planned welding position T2 has not been welded, it is determined that the welding has not been completed (step S113; No), and the process returns to step S102.

Since the control unit 50 includes data indicating that the laser L is irradiated while moving in the −x direction in the welding data for welding the planned welding position T2, it is determined that the laser L is irradiated while moving (step S102). Yes), it is determined that the laser L is irradiated while moving in the −x direction (step S103; No). Next, the control unit 50 controls the rotating unit 24 and rotates the flow path 22 by 180 ° from the reference position as shown in FIG. (Step S106). As a result, the central CP of the flow path 22 is arranged at a position separated from the central axis AX in the −x direction. Next, the control unit 50 executes control for opening the regulator 23 (step S107). As a result, the gas G injected from the injection port 25 rotated by 180 ° from the reference position is blown to the peripheral portion P2 and flows in the x direction, which is the direction of stroking the surface of the condensing point C of the laser L, so that the molten pool Stable airflow AF that does not disturb is generated. Therefore, it does not promote the oxidation of the molten pool. Next, the control unit 50 controls the robot unit 30 to start moving the laser emitting unit 10 and the gas injection unit 20 in the −x direction (step S108). Next, while moving the laser emitting unit 10 and the gas injection unit 20 in the −x direction, the control unit 50 controls the laser emitting unit 10 to shift the laser L to the first and second welding target members R1 and R2. (Step S112). The fume and spatter generated from the melted portion due to the heat input of the laser L are blown off by the airflow AF of the gas G in the x direction opposite to the −x direction, which is the moving direction, and are removed from the focusing point C of the laser L. .. Further, since the fume and spatter are blown off to the upper part of the already welded welded region Z1, the upper part of the unwelded region Z2 to be welded from now on has less fume and spatter. When the moving distance included in the welding data is moved, the control unit 50 controls the laser emitting unit 10 to stop the irradiation of the laser L, determines that the welding is completed (step S113; Yes), and the flow path 22. And the injection port 25 is returned to the reference position, and the welding process is completed.

When the control unit 50 includes data indicating that the welding is spot welding in which the laser L is irradiated without moving to the welding data, the control unit 50 determines that the laser L is irradiated without moving (step S102; No). Next, the control unit 50 controls the helicoid unit 27 and moves the nozzle 21 in the z direction (step S109). As a result, the injection port 25 of the gas injection unit 20 approaches the first and second welding target members R1 and R2. Next, the control unit 50 executes control for opening the regulator 23 (step S110). As a result, as shown in FIG. 10, the gas G injected from the injection port 25 is blown to the peripheral portion P1 and flows in the direction of stroking the surface of the condensing point C of the laser L, which disturbs the molten pool. No stable airflow AF occurs. Next, the control unit 50 controls the robot unit 30 to move the laser emission unit 10 and the gas injection unit 20 to the planned welding positions (step S111). Next, the control unit 50 controls the laser emitting unit 10 to irradiate the first and second welding target members R1 and R2 with the laser L (step S112). Fume and spatter generated from the portion melted by the heat input of the laser L are removed from the condensing point C of the laser L by the airflow AF of the gas G. After that, the control unit 50 controls the laser emitting unit 10 to stop the irradiation of the laser L and end the welding process.

As described above, according to the welding apparatus 100 and the welding method of the first embodiment, the gas G is sprayed on the peripheral portion P1 or the peripheral portion P2 and flows in the direction of stroking the surface of the condensing point C of the laser L. , Stable airflow AF that does not disturb the molten pool is generated. This makes it possible to remove fume and spatter that cause poor welding quality from the focusing point C of the laser L. In particular, it is highly effective in removing fume that causes a phenomenon called defocus in which the focusing point C of the laser L shifts in the −z direction. Further, in the case of spot welding, by blowing the gas G onto the peripheral portion P1 with the gas injection portion 20 lowered, fume and spatter can be removed from the condensing point C of the laser L. As a result, it is possible to provide a high-quality welding apparatus and welding method at low cost without using a shield gas. Further, in the design product including the design panel used for the elevator equipment, by removing the fume, the focus of the laser L is not shifted, so that the focusing point is stable and the irradiation energy density is stable, and the design surface DS is obtained. The penetration depth of the molten portion can be easily controlled at an output that does not generate welding traces, and both designability and joint strength can be satisfied.

On the other hand, assuming that the gas G is not blown, as shown in FIG. 11, the fume F generated from the portion melted by the heat input of the laser L remains, and the focusing point C of the laser L is in the −z direction. A phenomenon called defocus that shifts occurs. When the condensing point C is defocused, the energy density is low and the molten state is deteriorated, which may lead to welding defects including unwelded or sparse welding.
Further, since the laser L is scattered by the fume F and the sputter S, the energy density of the laser L becomes low, which may cause welding failure. Further, when a shield gas containing nitrogen and argon is used, since the shield gas is used for the purpose of removing oxygen from the focusing point C of the laser L, it is used by spraying it on a wide region including the focusing point C.
Therefore, if the flow rate of the shield gas per unit area is reduced, there is a problem that the fume F and the spatter S cannot be sufficiently removed. If the flow rate is increased, oxygen in the atmosphere is entrained in the molten portion, which has an adverse effect and may lead to poor welding quality.

(Modified example of the first embodiment)
In the above-described embodiment, an example in which the gas injection unit 20 has an injection port 25 has been described. The gas injection unit 20 may have at least one injection port. As shown in FIG. 12, the gas injection unit 20 may have

injection ports

61 and 62 in which the injection port 25 is divided into two. The injection ports 61 to 62 are arranged side by side in the circumferential direction. The injection ports 61 to 62 may each include a regulator that controls the flow rate of the gas independently. When the laser emitting unit 10 and the gas injection unit 20 are moved in the x direction, gas G is injected from the injection port 61 and the injection port 62. When the laser emitting unit 10 and the gas injection unit 20 are moved in the y direction, the flow path 22 and the injection port 25 are rotated by 90 ° from the reference position, the central CP of the injection port 25 is arranged in the y direction, and the injection port 61. And the gas G is injected from the injection port 62. Further, as shown in FIG. 13, the injection ports 71 to 74 having the circumference divided into four may be provided. Further, as shown in FIG. 14, the gas injection unit 20 may include a plurality of circular injection ports 81 along the circumference. In this case, the shape of the injection port 81 is not limited to a circle, but may be an ellipse or a polygon. By doing so, the flow velocity of the gas can be increased without increasing the flow rate of the gas.

In the above-described embodiment, an example in which the first welding target member R1 is a reinforcing member having a hat-shaped cross section and the second welding target member R2 is a design panel of an elevator facility has been described. The shapes of the first welding target member R1 and the second welding target member R2 are not particularly limited as long as they can be welded on top of each other. The shapes of the first welding target member R1 and the second welding target member R2 may include a curved surface shape as long as they can be welded on top of each other.

In the above-described embodiment, an example in which the gas injection unit 20 injects gas G, which is compressed air, has been described. The gas injection unit 20 may inject a gas G capable of removing fume and spatter, and the type of the gas G is not limited. Nitrogen gas may be used, and in this case, the strength of the welded portion can be further prevented from being lowered due to oxidation.

In the above-described embodiment, the robot unit 30 directs the laser emitting unit 10 and the gas injection unit 20 in the x direction with respect to the first welding target member R1 and the second welding target member R2 fixed to the surface plate 40. And an example of moving in the y direction has been described. The welding device 100 may move the laser emitting unit 10 and the gas injection unit 20 relative to the first welding target member R1 and the second welding target member R2 in the x direction or the y direction. The laser emitting unit 10 and the gas injection unit 20 may be fixed, and the first welding target member R1 and the second welding target member R2 may be moved in the x direction and the y direction. As shown in FIG. 15, when irradiating the laser L while moving the first welding target member R1 and the second welding target member R2 in the x direction, the rotating portion 24 is controlled and the flow path 22 is set to a reference position. It rotates 180 ° from and executes control to open the regulator 23. By doing so, the gas G flows in the x direction, which is the direction of stroking the surface of the condensing point C of the laser L, along the movement of the first welding target member R1, so that the molten pool is disturbed. No stable airflow AF occurs. As a result, the fume and spatter generated from the portion melted by the heat input of the laser L are blown off in the x direction, which is the moving direction of the first welding target member R1, by the airflow AF of the gas G, and the condensing point of the laser L. Removed from C. Further, since the fume and spatter are blown off to the upper part of the already welded welded region Z1, the fume and spatter are not present in the upper part of the unwelded region Z2 to be welded from now on.

(Second Embodiment)
In the first embodiment, an example in which the gas injection unit 20 has one injection port 25 and one injection port 25 of the gas injection unit 20 is rotated by the rotating unit 24 from the reference position has been described. The gas injection unit 20 only needs to be able to flow the gas G in the direction of stroking the surface of the condensing point C of the laser L, and the welding apparatus 100 of the second embodiment has a rotating unit 24 in the gas injection unit 20. Instead, it comprises a coaxial nozzle 28 having a first flow path 22A and a second flow path 22B. The configuration other than the gas injection unit 20 is the same as the configuration of the welding apparatus 100 of the first embodiment.

As shown in FIGS. 16 and 17, the gas injection unit 20 injects gas G, which is compressed air, into peripheral portions P1 and P2 of the condensing point C of the laser L. The gas injection unit 20 injects a coaxial nozzle 28 having a first flow path 22A and a second flow path 22B, a first regulator 23A and a second regulator 23B for controlling the flow rate of the gas G, and a gas G. It has a first injection port 25A and a second injection port 25B, an internal space 26 through which the laser L passes, and a helicoid portion 27 that moves the coaxial nozzle 28 in the z direction.

The coaxial nozzle 28 is a rotationally symmetric body centered on the central axis AX, and has a hollow tapered shape that shrinks in diameter as it advances in the z direction. The central axis AX is a path through which the laser L passes.

The first flow path 22A and the second flow path 22B are gas flow paths that surround the central axis AX, divide the central axis AX in the circumferential direction, and go from the laser emitting portion 10 toward the condensing point C. It is formed along the laser L in a path approaching the central axis AX. The gas G flowing through the first flow path 22A is injected from the first injection port 25A. The gas G flowing through the second flow path 22B is injected from the second injection port 25B. The first flow path 22A and the first injection port 25A are formed in a region in the x direction from the central axis AX. The second flow path 22B and the second injection port 25B are formed in a region in the −x direction from the central axis AX. The angle θ formed by the first flow path 22A or the second flow path 22B and the z-axis is preferably 3 ° or more and 30 ° or less, and more preferably 5 ° or more and 20 ° or less. The extension line of the first flow path 22A intersects the peripheral portion P1 of the condensing point C where the laser L is irradiated to the first welding target member R1. The extension line of the second flow path 22B intersects the peripheral portion P2 of the condensing point C where the laser L irradiates the first welding target member R1. The peripheral portion P1 is a position deviated from the condensing point C in the x direction, and the peripheral portion P2 is a position deviated from the condensing point C in the −x direction. When viewed in the z direction, the inlet portions of the first flow path 22A and the second flow path 22B each have a shape along a semicircular arc surrounding the central axis AX, as shown in FIG. 18A. Further, the first injection port 25A and the second injection port 25B each have a slit-like shape along a semicircular arc surrounding the central axis AX, as shown in FIG. 18B, when viewed in the z direction.

The first regulator 23A shown in FIG. 16 is controlled by a control unit (not shown) to adjust the flow rate of the gas G flowing through the first flow path 22A. The second regulator 23B is controlled by the control unit 50 to adjust the flow rate of the gas G flowing through the second flow path 22B. When irradiating the laser L after the laser emitting unit 10 and the gas injection unit 20 move in the x direction, the control of closing the second regulator 23B and opening the first regulator 23A is executed. As a result, the gas G is injected from the first injection port 25A. In this case, the gas G is blown to the peripheral portion P1 and flows in the −x direction, which is the direction of stroking the surface of the condensing point C of the laser L, so that a stable airflow AF that does not disturb the molten pool is generated. On the other hand, when irradiating the laser L while moving in the −x direction, the control of closing the first regulator 23A and opening the second regulator 23B is executed. As a result, the gas G is injected from the second injection port 25B, and the gas G is sprayed on the peripheral portion P2 and flows in the x direction, which is the direction of stroking the surface of the condensing point C of the laser L. Further, when the laser L is irradiated without moving, the control for opening the first regulator 23A and the second regulator 23B is executed. As a result, as shown in FIG. 19, the gas G is injected from the first injection port 25A and the second injection port 25B. Further, in the case of spot welding, the helicoid portion 27 is controlled by a control portion (not shown) to move the coaxial nozzle 28 in the z direction. As a result, the first injection port 25A and the second injection port 25B of the gas injection unit 20 approach the first and second welding target members R1 and R2. As a result, the gas G injected from the first and

second injection ports

25A and 25B is blown to the peripheral portions P1 and P2 and flows in a direction away from the condensing point C of the laser L, thereby disturbing the molten pool. Stable airflow AF is generated.

As described above, according to the welding apparatus 100 and the welding method of the second embodiment, the gas G is applied to the peripheral portion P1 or the peripheral portion P2 as in the welding apparatus 100 and the welding method of the first embodiment. Since it is blown and flows in the direction of stroking the surface of the condensing point C of the laser L, a stable airflow AF that does not disturb the molten pool is generated. Thereby, the welding apparatus 100 and the welding method of the second embodiment can obtain the same effect as the welding apparatus 100 and the welding method of the first embodiment.

(Modified example of the second embodiment)
In the second embodiment, an example in which the gas injection unit 20 has a first injection port 25A and a second injection port 25B has been described. The gas injection unit 20 may have at least a plurality of injection ports. As shown in FIG. 20, the gas injection unit 20 may have

injection ports

61 and 62 in which the first injection port 25A is divided into two and

injection ports

63 and 64 in which the second injection port 25B is divided into two. .. The injection ports 61 to 64 are arranged side by side in the circumferential direction. The injection ports 61 to 64 are provided with regulators that independently control the flow rate of the gas. In this case, the robot unit 30 can move the laser emitting unit 10 and the gas injection unit 20 in the x-direction and the y-direction. When the laser emitting unit 10 and the gas injection unit 20 are moved in the x direction, gas G is injected from the injection port 61 and the injection port 62. When the laser emitting unit 10 and the gas injection unit 20 are moved in the y direction, gas G is injected from the injection port 61 and the injection port 63. Further, as shown in FIG. 21, the injection ports 71 to 78 having the circumference divided into eight may be provided. In this case, even if the laser emitting unit 10 and the gas injection unit 20 are moved obliquely, the case can be dealt with.

In the above-described embodiment, an example in which the gas injection unit 20 has a slit-shaped injection port has been described. As shown in FIG. 22, the gas injection unit 20 may include a plurality of circular injection ports 81 along the circumference. In this case, when the laser emitting unit 10 and the gas injection unit 20 are moved in the x direction, the gas G is injected from the injection ports 81 of the

regions

82 and 83. Further, in this case, the shape of the injection port 81 is not limited to a circle, and may be an ellipse or a polygon.

(Modification example)
In the above-described embodiment, an example in which the laser emitting unit 10 uses a laser oscillator of a fiber laser or a disk laser that is excited by a semiconductor laser and emits a laser L has been described. The laser emitting unit 10 may irradiate the laser L that can be used for welding. The laser emitting unit 10 may use a transmitter that oscillates a laser by irradiating an optical fiber having a rare earth element added to the core with excitation light, or may use a transmitter using a YAG crystal. Further, the laser emitting unit 10 may irradiate an _{excimer laser or a CO 2 laser.}

In the above-described embodiment, an example in which the first and second welding target members R1 and R2 are metal members has been described. The first and second welding target members R1 and R2 may be glass plates or resin plates as long as they can be joined by welding.

In the above-described embodiment, an example in which the first and second welding target members R1 and R2 are used as a design panel for elevator equipment has been described. The equipment in which the first and second welding target members R1 and R2 are used is not limited, and the first and second welding target members R1 and R2 are indoors provided in a self-standing board including a switchboard and a control board, and an air conditioner. It may be used for machines and outdoor units, water heaters, lighting equipment, and the like.

The present disclosure allows for various embodiments and modifications without departing from the broad spirit and scope of the present disclosure. Moreover, the above-described embodiment is for explaining this disclosure, and does not limit the scope of the present disclosure. That is, the scope of the present disclosure is indicated by the scope of claims, not by the embodiment. And, various modifications made within the scope of claims and the equivalent meaning of disclosure are considered to be within the scope of this disclosure.

This application is based on Japanese Patent Application No. 2019-182656 filed on October 3, 2019. The specification, claims, and drawings of Japanese Patent Application No. 2019-182656 are incorporated herein by reference.

10 laser emission part, 20 gas injection part, 21 nozzle, 22 flow path, 22A first flow path, 22B second flow path, 23 regulator, 23A first regulator, 23B second regulator, 24 rotation part, 25 injection port, 25A first injection port, 25B second injection port, 26 internal space, 27 helicoid part, 28 coaxial nozzle, 30 robot part, 31 rail, 40 surface plate, 41 plane, 50 control unit, 51 CPU , 52 ROM, 53 RAM, 61-64, 71-78, 81 injection port, 82-85 area, 100 welding equipment, R1 first welding target member, R2 second welding target member, L laser, C condensing Point, G gas, P1, P2 peripheral part, DS design surface, θ angle, AX central axis, AF airflow, CP central part, r1, r2 diameter, w1 gap, T1, T2 planned welding position, F fume, S spatter, Z1 welded area, Z2 unwelded area.

Claims

A laser emitting part that emits a laser to a condensing point,
A gas injection unit that injects gas toward a peripheral portion of the condensing point is provided.
The laser emitting portion irradiates the welding target member with the laser while moving relative to the welding target member, and the gas injection portion moves the surface of the condensing point on the welding target member in the moving direction. Injects gas flowing in the opposite direction,
Welding equipment.
The gas injection unit has a gas flow path arranged at a position away from the path through which the laser passes, and a rotating unit that rotates the gas flow path around the path through which the laser passes.
The welding apparatus according to claim 1.
The gas flow path approaches the path through which the laser passes along the laser from the laser emitting portion to the focusing point.
The welding apparatus according to claim 2.
The gas flow path cut along a plane perpendicular to the path through which the laser passes has a shape along a semicircular arc surrounding the path through which the laser passes.
The welding apparatus according to claim 2 or 3.
A control unit for controlling the rotating unit is provided.
When irradiating the welding target member with the laser while moving the laser emitting portion in the first direction relative to the welding target member, the control unit controls the rotating portion, and the laser controls the rotating portion. The central part of the gas flow path is arranged in the first direction when viewed from the passing path.
The welding apparatus according to any one of claims 2 to 4.
When the control unit irradiates the welding target member with the laser while moving the laser emitting unit in a second direction opposite to the first direction relative to the welding target member. The rotating portion is controlled, the central portion of the gas flow path is arranged in the first direction, the gas flow path is rotated by 180 °, and the gas is viewed in the second direction as viewed from the path through which the laser passes. Place the center of the flow path,
The welding apparatus according to claim 5.
The gas injection unit includes an injection port having a slit-like shape along a semicircular arc surrounding a path through which the laser passes.
The welding apparatus according to any one of claims 1 to 6.
The gas injection unit determines the flow rates of the first gas flow path, the second gas flow path, and the gas flowing through the first gas flow path, which are arranged by dividing the circumference of the path through which the laser passes in the circumferential direction. A first regulator to control, a second regulator to control the flow rate of gas flowing through the second gas flow path, a first injection port for injecting gas flowing through the first gas flow path, and the above. It has a second injection port for injecting gas flowing through the second gas flow path, and has.
The first injection port injects gas flowing in a second direction opposite to the first direction on the surface of the light collecting point in the member to be welded.
The second injection port injects gas flowing in the first direction on the surface of the light collecting point in the member to be welded.
The welding apparatus according to claim 1.
A control unit for controlling the gas injection unit is provided.
When the control unit irradiates the welding target member with the laser while moving the laser emitting unit in the first direction relative to the welding target member, the control unit performs the first regulator and the second. To control the regulator of the above and inject gas from the first injection port.
The welding apparatus according to claim 8.
When the control unit irradiates the welding target member with the laser while moving the laser emitting unit in the second direction relative to the welding target member, the control unit performs the first regulator and the second. To control the regulator of the above and inject gas from the second injection port.
The welding apparatus according to claim 9.
When the control unit irradiates the welding target member with the laser without moving the laser emitting unit and spot welds the member, the control unit controls the first regulator and the second regulator to inject the first injection. Injecting gas from the port and the second injection port,
The welding apparatus according to claim 9 or 10.
The first injection port and the second injection port have a slit-like shape along an arc of a circle surrounding a path through which the laser passes.
The welding apparatus according to any one of claims 8 to 11.
The flow rate of the gas injected from the gas injection unit is at least a flow rate at which the fume can be removed.
The welding apparatus according to any one of claims 1 to 12.
A laser emitting part that emits a laser to a condensing point,
A gas injection unit that injects gas toward the periphery of the condensing point, and a gas injection unit.
Using a welding device equipped with
While moving the laser emitting portion relative to the member to be welded, the gas jetting portion injects gas flowing in the direction opposite to the moving direction to the surface of the condensing point in the member to be welded. The laser is applied to the member to be welded in which the gas flows on the surface.
Welding method.
When irradiating the welding target member with the laser while moving the laser emitting portion in the first direction relative to the welding target member, the light collecting point of the welding target member from the gas injection portion A gas flowing on the surface in a second direction opposite to the first direction is injected.
The welding method according to claim 14.
The gas injection unit has a gas flow path arranged at a position away from the path through which the laser passes, and a rotating unit that rotates the gas flow path around the path through which the laser passes.
When irradiating the welding target member with the laser while moving the laser emitting portion in the first direction relative to the welding target member, the rotating portion is controlled and the path through which the laser passes is used. The central part of the gas flow path is arranged in the first direction.
The welding method according to claim 15.
When irradiating the welding target member with the laser while moving the laser emitting portion in the second direction opposite to the first direction relative to the welding target member, the rotating portion is moved. Controlled, the gas flow path is rotated 180 ° from the state where the center portion of the gas flow path is arranged in the first direction, and the center of the gas flow path is seen from the path through which the laser passes. Place the part,
The welding method according to claim 16.
The flow rate of the gas injected from the gas injection unit is at least a flow rate capable of removing the fume generated from the portion melted by the heat input of the laser.
The welding method according to any one of claims 14 to 17.
The gas injected from the gas injection unit blows fume and spatter generated from the portion melted by the heat input of the laser from the unwelded region to be welded to the welded region already welded in the member to be welded.
The welding method according to any one of claims 14 to 18.
The gas injected from the gas injection unit is air.
The welding method according to any one of claims 14 to 19.