JP5579994B2 - Laser welding equipment - Google Patents

Description

The present invention includes a lens that condenses laser light and travels toward a processing site, transmits the laser light emitted from the lens, and protects the lens by blocking foreign matter generated from the processing site. It relates to a laser welding equipment provided with a.

  In order to prevent foreign matters such as fumes and spatters generated during laser welding from adhering to a condensing lens provided in the processing head, it is common to provide a protective glass. However, if the above-mentioned foreign matter adheres to this protective glass, the laser intensity at the processing site is lowered, and the foreign matter is also blown away by air blow (see Patent Document 1 below).

JP 59-16692 A

  However, the method of blowing off foreign matter by air blow to suppress adhesion to the protective glass is effective for floating components such as fumes, which are metal evaporation components, but is less effective particularly for sputters with large grains. Such spatter adheres to the protective glass and causes a decrease in laser output.

  Therefore, the present invention aims to suppress adhesion to a protective member even for spatters having particularly large grains.

The present invention is provided with a protective member that protects the lens by blocking foreign matter generated from the processing site, and the foreign material that can move along the protection member on the processing site side of the protective member and scatters from the processing site. A moving body that bounces off is provided , and the moving body is made of a material having non-absorptivity and non-evaporation properties with respect to laser light, and is faster as the plate thickness is thinner, and the scattering speed of the foreign matter is higher. The rotating body rotates faster along the protective member as the speed increases, and gas releasing means is provided to discharge gas toward the vicinity of the rotating body and blow off the foreign matter, and the gas discharged from the gas discharging means is received. A pressure receiving portion for rotating the rotating body is provided in the rotating body, and the rotating body is provided with a plurality of through holes as a flat plate shape, and a protrusion protruding radially outward is formed on an outer peripheral portion. Pressure receiving part is formed And wherein the are.

According to the present invention, even spatter with large grains can be sputtered off when the moving body moves, so that spatter adherence to the protective member protecting the lens for condensing laser light can be suppressed. it can.
In addition, since the rotating body is used as the moving body for jumping off the foreign matter, the scattered foreign matter can be continuously and efficiently jumped off, and the adhesion of the foreign matter to the protective member can be efficiently suppressed.
Further, since the above-described rotating body has a flat plate shape and is provided with a plurality of through holes, it is possible to bounce off foreign matters at the periphery of the through holes and allow the laser beam to reach the processing site through the through holes.
Further, by increasing the rotational speed of the rotating body as the plate thickness of the rotating body is thinner, it is possible to efficiently fly off the scattered foreign matter while reducing the weight of the rotating body. Furthermore, by increasing the rotational speed of the rotating body as the scattering speed of the foreign matter increases, it is possible to efficiently jump off the foreign matter having a high scattering speed.
Moreover, since the rotating body is made of a material having non-absorbing and non-evaporating properties with respect to the laser light, it is possible to suppress the deterioration of the rotating body and to prevent the protective member from being damaged.
Further, gas releasing means for discharging gas and blowing away foreign matter is provided in the vicinity of the rotating body, and a pressure receiving portion for receiving the gas released from the gas releasing means and rotating the rotating body is provided on the rotating body. For this reason, it is not necessary to separately provide a dedicated drive source for rotating the rotating body, and the rotating body can be rotated with a simple structure while suppressing the equipment cost.

It is the simplified front view of the laser welding apparatus which shows one Embodiment of this invention. It is a top view which shows the positional relationship of the rotary body and protective glass in the laser welding apparatus of FIG.

  Hereinafter, embodiments of the present invention will be described with reference to the drawings.

  As shown in FIG. 1, a laser welding apparatus according to an embodiment of the present invention applies laser light 3 emitted from a laser processing head 1 called a scanner to a welding site that is a predetermined processing site of a workpiece W that is a workpiece. Irradiation and remote laser welding are performed.

  In this remote laser welding, the laser processing head 1 mainly includes a condensing lens 2 and two movable mirrors 4 and 6, and laser light oscillated from a laser oscillator (not shown) is transmitted through the lens 2. By reflecting with the two movable mirrors 4 and 6, the irradiation direction of the laser beam 3 is changed while the laser processing head 1 is set at a fixed position. Accordingly, in FIG. 1 where the laser beam 3 from the laser processing head 1 is emitted, an opening corresponding to the irradiation direction in which the laser beam 3 changes is provided on the lower surface.

  Each of the mirrors 4 and 6 has uniaxial or biaxial variable degrees of freedom. The variable degrees of freedom of these mirrors 4 and 6 are not limited to instantaneous movement of the welded part, but also at a specific welded part. It is used for continuous movement of the laser beam irradiation position.

  On the front side of the laser processing head 1 from which the laser beam 3 is emitted, a protective glass 5 as a protective member for protecting the condensing lens 2 and the mirrors 4 and 6 from fumes F and spatter S generated during welding. Is provided via a fixture 7. Further, a disk-shaped rotating body 9 as a moving body is provided on the workpiece W side including the welded portion of the protective glass 5. The rotating body 9 is rotatably attached to the lower end of the rotation support shaft 11 provided at the center thereof, and the rotation support shaft 11 is positioned in the vicinity of the side edge of the protective glass 5 on the front side in FIG. The upper end is attached to the laser processing head 1.

  The rotating body 9 is provided with a plurality of circular through holes 13 as shown in a plan view in FIG. These through-holes 13 are provided with a plurality of large holes 13a, medium holes 13b, and small holes 13c at appropriate positions, so that the area occupied by the through-holes 13 with respect to the entire rotating body 9 is widened, thereby obstructing the passage of the laser light 3. I try not to come. In addition, a semicircular cutout portion 15 having a larger radius than the large hole 13a is provided on the outer peripheral portion of the rotating body 9 over the entire circumference along the circumferential direction. Is formed with a protrusion 17 protruding outward in the radial direction of the rotating body 9. The through holes 13 and the notches 15 are provided almost uniformly over the entire area of the rotating body 9.

Such rotary member 9, and hardly absorbs the laser beam 3, the evaporation material hardly be subjected to laser beam 3, i.e. material having the properties of non-absorbing and non-evaporable for the laser beam 3, e.g. It is made of tungsten or copper.

  As shown in FIG. 2, the protective glass 5 is a rectangle that is long in the left-right direction in FIGS. 1 and 2, and the rotating body 9 is on one side (left side in FIG. 2) with respect to the rectangular protective glass 5. The positions are close to each other, and the upper half of FIG.

  Although not particularly shown in FIG. 2, the outer shape of the tip of the laser processing head 1 in plan view is slightly larger than the protective glass 5.

  Here, in FIG. 2, the passing area of the laser light 3 in the protective glass 5 is indicated by a rectangular A, but this passing area A is in FIG. 2 with respect to the area overlapping the protective glass 5 of the rotating body 9. It is slightly shifted to the upper right. The passing area A substantially corresponds to the opening corresponding to the changing irradiation direction of the laser beam 3 provided on the lower surface of the laser processing head 1 described above.

  Further, a plurality of air nozzles 19 serving as gas releasing means for releasing air as gas toward the vicinity of the rotating body 9 are provided on the lower surface of the right end portion of the laser processing head 1 in FIG. Three are attached here.

  On the other hand, as shown in FIG. 1, air receiving plates 23 serving as a plurality of pressure receiving portions are attached to the lower surface on the work W side on the outer peripheral side of the rotating body 9 along the circumferential direction. As shown by a broken line in FIG. 2, the air receiving plate 23 has a curved surface shape at a position corresponding to each protrusion 17 along the arc shape of the semicircular cutout portion 15. The air receiving plate 23 does not need to be provided corresponding to all the protrusions 17, and may be provided every other protrusion 17 in the circumferential direction, for example.

  Here, the air emission direction by the three air nozzles 19 corresponds to the air receiving plate 23 below the rotating body 9 as shown in FIG. 1, and as shown in FIG. 3 corresponding to the passage area A of 3. As a result, the air released from the air nozzle 19 blows off a part of the fume F and spatter S, which are foreign matters generated during welding, and at the same time, air is blown, and at the same time, the air acts on the air receiving plate 23, so Rotate.

  That is, the rotating body 9 that is a moving body is provided on the front side in the discharge direction of the gas that is discharged from the air nozzle 19 that is a gas discharging means.

  Next, the operation will be described. When laser welding is performed by irradiating the workpiece W with the laser beam 3 from the laser processing head 1, fume F and spatter S are scattered from the welded portion. At that time, the fume F and particularly the spatter S having small grains and small mass can be blown off by the air discharged from the air nozzle 19 and air blown, and adhesion of these foreign substances to the protective glass 5 can be suppressed to some extent.

  However, it is difficult to blow off the sputter S having large grains and large mass by air blow. Here, in the present embodiment, the air receiving plate 23 receives the air discharged from the air nozzle 19 and the rotating body 9 rotates. Due to the rotation of the rotating body 9, the sputter S having particularly large grains that could not be blown by air physically jumps off at the periphery when the spatter S reaches the through-hole 13 or the notch portion 17, and suppresses reaching the protective glass 5. .

  Thereby, especially the sputter | spatter S with a big grain can suppress adhesion to the protective glass 5, and can suppress the fall of the laser intensity in a welding part, and can perform highly efficient laser welding. Moreover, the cleaning frequency and replacement frequency of the protective glass 5 are reduced, and the work efficiency and the work cost can be improved.

  In order to efficiently sputter the spatter S by the rotation of the rotating body 9, it is desirable to make the rotating speed of the rotating body 9 as fast as possible. However, since the rotational speed of the rotator 9 necessary for jumping off the sputter S is related to the thickness of the rotator 9 and the spatter speed of the sputter S, in this embodiment, the spatter speed of the sputter S is about 5 m / second. The diameter of the through hole 13 (large hole 13a) is about 20 mm, for example, 10 rotations / second.

  The rotational speed of the rotator 9 is adjusted by the flow rate and flow rate of the air discharged from the air nozzle 19, or the shape and the number of installed air receiving plates 23.

  Further, the laser output oscillated from a laser oscillator (not shown) is changed depending on whether the laser beam passes through the installation area of the rotating body 9 or not. In other words, the laser output when the laser beam passes through the installation area of the rotator 9 is higher than the laser output when the laser beam does not pass through the installation area of the rotator 9, so that the laser intensity when reaching the workpiece W is increased. To improve the quality of welded products.

  Moreover, in this embodiment, since the rotary body 9 is used as the moving body that jumps off the spatter S, the spatter S that is scattered can be continuously and efficiently spattered, and the sputter S on the protective glass 5 can be splashed. Adhesion can be efficiently suppressed.

  Further, since the rotating body 9 described above has a plurality of through holes 13 in a flat plate shape, the sputter S is bounced off at the periphery of the through holes 13 and the laser beam 3 reaches the workpiece W through the through holes 13. be able to.

  In the present embodiment, the rotational speed of the rotator 9 is increased as the plate thickness of the rotator 9 is decreased, so that the spatter S that is scattered can be efficiently splashed while reducing the weight of the rotator 9. be able to.

  Further, by increasing the rotational speed of the rotating body 9 as the spattering speed of the sputter S increases, it is possible to efficiently bounce off the sputter S having a high scattering speed.

  In the present embodiment, the diameter of the through-hole 13 is set to 20 mm, and the rotation speed of the rotating body 9 is set to 10 rotations / second, so that the sputtering scattering speed, which is normally observed, is about 5 m / second. On the other hand, it is possible to jump efficiently.

  Further, in the present embodiment, the rotating body 9 that is a moving body is made of, for example, tungsten that has non-absorptive and non-evaporable properties with respect to the laser light 3, so that deterioration of the rotating body 9 is suppressed, In addition, the protective glass 21 can be prevented from being stained. When the rotator 9 is made of a material that absorbs or evaporates with respect to the laser beam 3, the rotating pair 9 is melted and deteriorated, and the protective glass 21 is caused by vapor generated when the rotator 9 is melted. It will be soiled.

  Further, in the present embodiment, an air nozzle 19 that releases air in the vicinity of the rotating body 9 and blows away a part of the fumes F and spatter S is provided, and the air that rotates the rotating body 9 by receiving the air discharged from the air nozzle 19 is provided. A receiving plate 23 is provided on the rotating body 19. For this reason, it is not necessary to provide a dedicated drive source for rotating the rotator 9 in particular, and the rotator 9 can be rotated with a simple structure while reducing the equipment cost.

  In the present embodiment, since the rotating body 9 is provided in the vicinity of the protective glass 5, the position where the spot diameter of the laser beam 3 condensed by the condensing lens 2 is not reduced (position where the laser density is low). Thus, the laser beam 3 passes through the rotating body 9, and the workpiece W can be irradiated with the laser beam 3 having a stable intensity.

  Further, the rotating body 9 is provided on the front side in the emission direction of the air emitted from the air nozzle 19 in the laser light passage area A in the area where the sputter S is scattered toward the protective glass 5. That is, in FIG. 2, the region B close to the air nozzle 19 in the passage region A has a strong momentum of air discharged from the air nozzle 19, so that even the sputter S having relatively large grains can be blown away. Even if the rotating body 9 is installed only on the front side in the air discharge direction from B, the adhesion of the sputter S to the protective glass 5 can be suppressed. Thereby, it can suppress that the rotary body 9 is enlarged more than necessary, the area | region where the laser beam 3 passes the rotary body 9 can be narrowed more, and it can contribute also to the weight reduction of the laser processing head 1. FIG. .

  In the above-described embodiment, the rotating body 9 is rotated by the air nozzle 19. However, the rotating body 9 may be rotated by using a dedicated drive source such as an electric motor or an air motor. In this case, the rotating body 9 is stabilized. Since the rotation speed can be easily controlled, the sputter S can be more efficiently jumped off.

  The rotating body 9 may be provided with slit-like through holes instead of the circular through holes 13. Further, the rotating body is not limited to the disk-shaped member provided with the through-holes 13, but may be a net-shaped member or a plurality of arms extending radially from the center of rotation in the circumferential direction. When the rotating body is simply a rod-shaped arm, the manufacturing is easy and it can contribute to the reduction of the equipment cost.

  Further, not only the rotating body 9 as the moving body, but also a reciprocating movement using a linear motor, for example, may be used.

  In the above-described embodiment, the present invention is applied to the remote laser welding apparatus in which the irradiation direction of the laser beam 3 emitted from the laser processing head 1 is variable by the two mirrors 4 and 6. The invention may be adapted.

2 Condensing lens 3 Laser light 5 Protective glass (protective member)
9 Rotating body (moving body)
13 Through-hole provided in rotator 19 Air nozzle (gas release means)
23 Air receiving part (pressure receiving part)
S Spatter (foreign matter)

Claims (4)

A protective member that includes a lens that focuses the laser light and travels it toward the processing site, transmits the laser light emitted from the lens, and shields the foreign matter generated from the processing site and protects the lens. A laser welding apparatus comprising:
Provided on the processing site side of the protection member is a movable body that is movable along the protection member and that bounces off the foreign matter scattered from the processing site ,
The moving body is made of a material having non-absorptivity and non-evaporation properties with respect to laser light, and is faster as the plate thickness is thinner and faster as the scattering speed of the foreign matter is faster. A rotating body that rotates along
A gas discharge unit that discharges gas toward the vicinity of the rotating body and blows off the foreign matter is provided, and a pressure receiving unit that receives the gas discharged from the gas discharging unit and rotates the rotating body is provided in the rotating body.
The rotating body is provided with a plurality of through-holes as a flat plate shape, a protrusion protruding outward in the radial direction is formed on an outer peripheral portion, and the pressure receiving portion is formed on the protrusion. . Laser welding apparatus according to claim 1, wherein the diameter of the through hole as 20 mm, and a rotation speed of the rotating body at least 10 rotations / sec. Laser welding apparatus according to claim 1 or 2, characterized in that a movable body in the vicinity of the protection member. Wherein in the region where foreign matter splashed toward the protective member, in the discharge direction front side of the gas released from the gas release means, of claims 1 to 3, characterized in that a movable body The laser welding apparatus according to any one of claims.

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