JP4233625B2 - Metal sheet welding method - Google Patents

Description

[0001]
BACKGROUND OF THE INVENTION
The present invention relates to a method for welding a thin metal plate that welds the thin metal plate to a central axis, and more particularly, to a method for welding a thin metal plate that is welded with a laser beam.
[0002]
[Prior art]
Conventionally, as a method of welding a thin metal plate to a central axis, for example, there is a method shown in FIG.
[0003]
This conventional welding method pressurizes the thin metal plate 110 from above with the shaft fitting portion 111 formed of a circular hole provided at the center of the thin metal plate 110 being fitted into the protruding shaft portion 121 of the central shaft 120. A current flows from the electrode 130 and the electrode 150 connected to the central axis 120 and the wires 141 and 142 between the electrode 130 to be pressed and the central axis 120, and the thin metal plate 110 is placed on the central axis 120 by heat generated by contact resistance. I was trying to weld it.
[0004]
[Problems to be solved by the invention]
However, the conventional welding method has a problem in that the electrode 150 has a life and it is necessary to replace the electrode 150 every several hundred shots, which is troublesome.
[0005]
In addition, since the current flow varies greatly depending on the contact state depending on the roughness and shape of the surface of the metal thin plate 110, there is a problem that there is a limit to performing high-quality welding.
[0006]
The present invention solves the above-described conventional problems, and by welding using a laser beam, a metal thin plate can be stably welded without tilting to the central axis, and a metal capable of performing high-quality welding. It aims at providing the welding method of a thin plate.
[0007]
[Means for Solving the Problems]
In order to solve the above-mentioned problems, the present invention provides a metal thin plate having a shaft insertion portion formed in the central portion, a protruding shaft portion inserted into the shaft insertion portion, and a shoulder formed at the base of the protruding shaft portion. In the welding method of a thin metal plate that is welded to a central shaft having a portion, the periphery of the shaft fitting portion of the thin metal plate is inserted in a state in which the protruding shaft portion of the central shaft is fitted into the shaft fitting portion of the thin metal plate. A method of welding a thin metal plate, wherein a plurality of pulsed laser beams having equal energy while rotating relatively on the same circumference are welded to a shoulder portion of the central shaft, wherein the thin metal plate is inserted into the shaft. After pressing the periphery of the part with the pressing means, fixing a plurality of locations excluding the pressing position by the pressing means by welding with pulsed laser light having equal energy, and removing the pressing means, the shaft insertion portion of the thin metal plate Around The plurality of pulsed laser beams are welded to the shoulder portion of the central axis while relatively rotating.
[0008]
[0009]
[0010]
[0011]
[0012]
[0013]
According to the present invention, the projecting shaft portion of the central shaft is fitted into the shaft fitting portion of the thin metal plate, and in this state, a plurality of pulsed lasers having equal energy while relatively rotating around the thin metal plate on the same circumference Since multiple spots are welded to the shoulder of the central axis with light, laser irradiation is performed in a balanced manner with the same energy and equal conditions, and the reaction force generated by proof and spatter generated during laser welding is offset and stable welding without tilt is performed. And high-quality welding can be reliably performed.
[0014]
Also, press the periphery of the shaft insertion part of the thin metal plate with the pressing means, and fix it by welding with pulsed laser light having equal energy, then remove this pressing means, and then around the shaft insertion part of the thin metal plate Since a plurality of pulsed laser beams are welded to the shoulder portion of the central axis while relatively rotating, good welding can be performed even if there is a gap in the thickness of the thin metal plate.
[0015]
[0016]
[0017]
[0018]
[0019]
[0020]
DETAILED DESCRIPTION OF THE INVENTION
Hereinafter, reference examples and embodiments of the present invention will be described with reference to the drawings.
[0021]
FIG. 1 shows a welding method for a thin metal plate according to a first reference example . The welding method for a thin metal plate according to the first reference example includes a shaft insertion portion 11 formed of a circular hole at the center of a circular thin metal plate 10. The metal thin plate 10 is placed on the shoulder portion 22 of the central shaft 20 by being fitted into the protruding shaft portion 21 of the central shaft 20, and the contact portion between the metal thin plate 10 and the shoulder portion 22 of the central shaft 20 is equienergetic and The pulsed laser beam 30 having the same focused spot diameter is irradiated while rotating around the shaft insertion portion 11 of the thin metal plate 10 to weld the same circumference of the thin metal plate 10 to the shoulder portion 22 of the central shaft 20.
[0022]
In addition, it is preferable that the plate | board thickness of the metal thin plate 10 is 0.3 mm or less, the spot diameter of the pulsed laser beam 30 is 0.1 mm diameter, and energy is several joules.
[0023]
Moreover, it is suitable for the surface finish quality of the metal thin plate 10 to raise the irradiation waveform of the pulsed laser beam 30 stepwise.
[0024]
In the welding method of the metal thin plate of the first reference example , the pulsed laser beam 30 is laser-irradiated on the metal thin plate 10 in a balanced manner under the same energy and equal conditions, so that the reaction force caused by proof or spatter generated during laser welding is reduced. As a result, the thin metal plate 10 can be stably welded to the center shaft 20 without tilting, and high-quality welding can be reliably performed.
[0025]
Figure 2 is a view illustrating the welding method of the embodiment of the sheet metal of the present invention, a method of welding the sheet metal of the implementation form of this, the shaft fitting portion 11 comprising a circular hole in the center of the circular sheet metal 10 In a state of being fitted into the projecting shaft portion 21 of the central shaft 20, a symmetric position from the projecting shaft portion 21 on the surface of the circular metal thin plate 10 was pressed with equal force by the pressing means 40, 40 comprising pressing pins. In this state, the position rotated 90 degrees from the pressing means 40, 40 and symmetrical from the protruding shaft portion 21 is fixed by irradiating the pulsed laser beams 30, 30 with the same energy and the same focused spot diameter. To do.
[0026]
Thereafter, after removing the pressing means 40, 40, the entire circumference of the thin metal plate 10 is welded to the shoulder portion 22 of the central shaft 20 while irradiating the surface of the thin metal plate 10 with the pulsed laser beams 30, 30.
[0027]
The welding method of the sheet metal of the implementation form of this, pressing the surface of the sheet metal 10 by pressing means 40 and 40, about the axis fitting portion of the sheet metal 10 in a pulsed laser beam 30, 30 of the central shaft 20 After fixing to the shoulder portion 22, the entire circumference of the thin metal plate is welded at a plurality of locations, so that even if there is a gap in the thickness of the thin metal plate, good welding can be performed.
[0028]
FIG. 3 shows a welding method for a thin metal plate according to a second reference example . The welding method for the thin metal plate according to the second reference example includes a shaft insertion portion 11 formed of a circular hole at the center of a circular thin metal plate 10. In the state of being fitted into the protruding shaft portion 21 of the central shaft 20, the pulsed laser beam 30 is emitted while being pressed against the metal thin plate 10 so as to mesh with the protruding shaft portion 21 of the central shaft 20 by the pressing means 41 made of a pressing rod. A plurality of generated laser emitting lens barrels 35 are rotated together with the pressing means 41, and a plurality of central portions around the shaft fitting portion 11 of the thin metal plate 10 are irradiated with pulsed laser light 30 from the plurality of laser emitting lens barrels 35. Weld to 20 shoulders 22.
[0029]
In addition, it is suitable to use the thing which gave the ceramic coat | court for the holding | suppressing means 41 which consists of a pressing rod, in order to give abrasion resistance. Further, it is preferable to remove the point at which the metal thin plate 10 is pressed by the holding means 41 from the same circumference of the metal thin plate 10 irradiated with the pulsed laser light so as not to damage the laser emitting barrel 35.
[0030]
In the welding method of the thin metal plate of the second reference example , the periphery of the shaft insertion portion 11 of the thin metal plate 10 is pressed by the pressing means 41, and both the pressing means 41 and the plurality of pulsed laser beams 30 of the shaft insertion portion 11 are pressed. Since the periphery of the shaft insertion portion 11 of the thin metal plate 10 is welded to the shoulder portion 22 of the central shaft 20 with a plurality of pulsed laser beams 30 while rotating around the periphery, there is a slight gap in the thickness of the thin metal plate 10. Even if it exists, favorable welding can be performed.
[0031]
FIG. 4 schematically shows a welding method for a metal thin plate according to a third reference example . The welding method for the metal thin plate according to the third reference example is a YAG laser generated from a YAG laser device 51 through an optical fiber 52. The light is converted into parallel light by the convex lens 53 of the fixed optical system 50, reflected by the first half mirror 54 that is highly reflected at the wavelength of the YAG laser light, and a parallel beam 56 having a diameter of 2 cm centered on the laser beam central axis 55. It becomes. Further, the parallel beam 56 is attached to the same rotating optical system 60 as the output lens barrel 35 and is reflected by a second half mirror 61 that reflects 50% of YAG laser light and a third half mirror 62 that reflects 100% of YAG laser light. The light is divided into two, condensed by two convex lenses 63 and 63, and incident on two optical fibers 64 and 64. At this time, the two condensing spots 65 and 65 condense smaller than the incident cross-sectional area of the optical fibers 64 and 64, so that the center of the laser beam of the fixed optical system 50 to which the convex lens 53 and the first half mirror 54 are attached. Even if the shaft 55 and the central axis 66 of the rotating optical system 60 are somewhat mechanically centered, the incident cross-sectional area of the optical fibers 64 and 64 is always collected by the convex lenses 63 and 63 that vary due to the centering. Therefore, the power fluctuation of the optical fibers 64 and 64 hardly occurs. The laser light incident on the optical fibers 64 and 64 is applied to the metal thin plate 10 from the laser emission barrels 35 and 35 provided at the ends.
[0032]
As each condition, it is preferable that the optical fibers 52, 64, and 64 use the GI type rather than the SI type because the beam is concentrated at the center.
[0033]
Further, the condensing distance of the convex lenses 63 and 63 is preferably shorter than the convex lens 53 in order to reduce the beam size.
[0034]
In the welding method of the metal thin plate of the third reference example , the laser beam from the fixed optical system 50 can be obtained by welding the periphery of the shaft insertion portion 11 of the metal thin plate 10 with laser light from the fixed optical system 50 and the rotating optical system 60. Even if there is a fluctuation in the center of light irradiation, the shoulder 22 of the central axis 20 around the shaft insertion portion 11 of the metal thin plate 10 is eliminated by irradiating the laser beam from the rotating optical system 60 while eliminating the fluctuation of the laser irradiation spot position. Can be welded at a plurality of locations, and stable laser beam welding can be performed.
[0035]
FIG. 5 shows a method for welding a thin metal plate of a fourth reference example .
[0036]
As shown in FIG. 6, it is known as a publicly known fact that the size of the gap G of the contact surface at the welded part greatly affects the welding quality, as shown in FIG. The gap G is preferably 1/10 or less of the plate thickness. When the gap G is 1/4 or less, it is difficult to perform welding by ordinary YAG laser welding, and high-luminance laser characteristics that are highly soluble in the center are required. In any case, if the beam quality of the spot of the welding irradiation part is ensured, as shown in FIG. 5, the reference height H of the thin metal plate 10 during or before laser welding is measured by the distance sensor 70, If the change is within a certain amount, it can be regarded as a non-defective product.
[0037]
FIG. 7 shows a welding method for a metal thin plate according to a fifth reference example , in which not only the height but also the inclination of the metal thin plate 10 can be detected by a laser beam instead of a distance sensor.
[0038]
The parallel laser light R <b> 1 emitted from the laser light source 75 is reflected by the surface of the thin metal plate 10 and hits the linear sensor 76. If the thin metal plate 10 is inclined as indicated by a broken line, the linear sensor 76 is inclined to follow another path like the laser beam R2 as compared with the case where the thin metal plate 10 is horizontal as indicated by a solid line. Can be detected.
[0039]
FIG. 8 shows a welding method for a thin metal plate according to a modified example of the second reference example described above, in which a pressing means 42 made of a pressing bar is used instead of the pressing bar, and the thin metal plate 10 is inserted into the shaft. When the portion 11 is formed of a raised portion 11A provided with a recessed portion 11a into which the protruding shaft portion 21 of the central shaft 20 is fitted on the back surface side, the recessed portion 11a on the back surface side of the raised portion 11A is In a state of being inserted into the protruding shaft portion 21, the protruding portion 11 </ b> A is pressed by the pressing means 42 made of a concave pressing rod, and the periphery of the shaft insertion portion 11 of the thin metal plate 10 is welded with the laser beam 30 emitted from the emission barrel 35. Like to do.
[0040]
FIG. 9 shows a welding method for a thin metal plate according to a modification of the third reference example described above. YAG laser light from the branch mirrors 66 and 66 of the rotating optical system 60A is turned back using the return mirrors 67 and 67. The parallel laser beams 69 and 69 may be guided directly to 63 and 63 and condensed on the surface of the thin metal plate 10.
[0041]
Further, as shown in FIG. 10, the optical fiber 52A from the laser device 51 may be directly guided to the output lens barrels 35 and 35, while the rotation optical system 60B may be changed in rotation direction every half rotation.
[0042]
In the form of the above you facilities it has been described circular ones as sheet metal, not limited to this, for example, quadrilateral sheet metal also is applicable.
[0043]
【The invention's effect】
According to the present invention, a laser beam is used to irradiate a thin metal plate with equal energy and equal conditions using a laser beam, so that the reaction force caused by proof and spatter generated during laser welding is offset and the thin metal plate is tilted about the central axis. Therefore, stable welding can be performed, and high-quality welding can be performed.
[Brief description of the drawings]
1A and 1B show a method for welding a metal thin plate according to a first reference example of the present invention, in which FIG. 1A is a partially sectional front view during welding, and FIG. 1B is a plan view when welding.
2A and 2B show a method for welding a thin metal plate according to an embodiment of the present invention, wherein FIG. 2A is a plan view showing a state in which the thin metal plate is pressed by a pressing means and fixed to a central axis, and FIG. 2B is a state in FIG. (C) is a top view which shows the state which removes a press means and welds, (d) is a front view of the state which removed the press means.
3A and 3B show a welding method for a thin metal plate according to a second reference example , wherein FIG. 3A is a plan view during welding, and FIG. 3B is a front view with a partial cross section during welding.
FIG. 4 is a schematic front view showing a welding method for a metal thin plate according to a third reference example .
FIG. 5 is a schematic front view, partly in section, illustrating a method for welding a thin metal plate of a fourth reference example .
FIG. 6 is an explanatory diagram for explaining a gap of the thin metal plate with respect to the central axis in the thin metal plate welding method.
FIG. 7 is an explanatory view showing a welding method for a metal thin plate according to a fifth reference example.
FIG. 8 is a partially sectional front view showing a method of welding a thin metal plate according to a modification of the second reference example .
FIG. 9 is a schematic front view showing a method of welding a thin metal plate according to a modification of the third reference example .
FIG. 10 is a schematic front view showing a method of welding a thin metal plate according to another modification of the third reference example .
FIG. 11 is an explanatory view showing a conventional method of welding a thin metal plate.
[Explanation of symbols]
DESCRIPTION OF SYMBOLS 10 Metal thin plate 11 Shaft insertion part 20 Center axis | shaft 21 Projection shaft part 22 Shoulder part 30 Pulse laser beam 35 Emitting lens barrel 40 Holding means 41 Holding means 42 Holding means 50 Fixed optical system 51 Laser apparatus 52 Optical fiber 54 1st half mirror 60 Rotating optical system 61 Second half mirror 62 Third half mirror 64 Optical fiber 65 Condensing spot 76 Linear sensor (measuring means)

Claims (1)

A metal in which a thin metal plate having a shaft insertion portion formed at the center is welded to a center shaft having a protruding shaft portion inserted into the shaft insertion portion and a shoulder portion formed at the base of the protruding shaft portion. In the thin plate welding method, in a state where the protruding shaft portion of the central shaft is inserted into the shaft insertion portion of the metal thin plate, the periphery of the shaft insertion portion of the metal thin plate is relatively energized while relatively rotating on the same circumference. A metal thin plate welding method in which a plurality of pulsed laser beams are welded to a shoulder portion of the central shaft, and the periphery of the shaft fitting portion of the metal thin plate is pressed by a pressing means. A plurality of pulsed lasers are fixed while being relatively rotated around the shaft fitting portion of the metal thin plate after fixing the plurality of places except for the pressed parts by welding with a pulsed laser beam having equal energy and removing the holding means. A method for welding a thin metal plate, wherein a plurality of locations are welded to the shoulder portion of the central axis with light.

Images