JPS59223191A - Laser welding device - Google Patents

Abstract

PURPOSE:To protect a condenser lens and to shield stably a welding part with gas by providing a nozzle which discharges high-velocity gas in the form of a film across the optical axis of the condenser lens and a nozzle which discharges low-velocity shielding gas near the focusing point of a laser beam. CONSTITUTION:A lens protecting nozzle 21 which discharges lens protecting gas such as air, nitrogen or the like for protecting a condenser lens 5 against spatter in the form of a film across the optical axis of the lens from a nozzle hole 21a is attached to the top end of a working head body 1. The nozzle hole 21a of said nozzle 21 is made into approximately a sectorial shape in, for example, the plane shape thereof and is so formed that the lens protecting gas covers the entire surface of the lens 5. A nozzle 22 for supplying shielding gas such as gaseous Ar at a relatively low flow rate is coupled and fixed to the body 1 by means of a coupling member 23 near the focusing point 4a of a laser beam 4.

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a radar welding device that performs laser welding by irradiating the surface of a member to be welded with a laser beam.

Generally, a radar welding device performs laser welding by irradiating a laser beam onto the surface of a workpiece.

In order to prevent the occurrence of welding defects, laser welding is performed after a shield of alponic gas or the like is supplied to the welding location of the welded member. FIG. 1 is a sectional view showing the tip of a conventional laser welding device.

In the figure, numeral 1 is the tip; %2 is the nozzle adapter attached to the tip of the processing head body; 3 is the nozzle adapter attached to the tip of the processing head body 1;
is a nozzle attached to the tip of the nozzle adapter 2. A condenser lens 5 is provided within the processing head main body 1 to focus a radar beam 4 emitted from a laser oscillation section of the main body of the harpoon device (not shown). Further, a shield gas supply port 6 is provided in the processing head main body 1 near the exit surface 5a of the condenser lens 5 to supply shield gas such as argon to the welding location of the workpiece (not shown). There is. That is, in the conventional laser welding device, the shielding gas supplied into the processing head main body 1 from the shielding gas supply port 6 is sent to the nozzle 3 together with the laser beam 4.
It is ejected from the welding part to the welding location.

By the way, the shield gas supply port 6 provided near the exit surface 5a of the condensing lens 5 as described above.

Normally, it serves both as a shield for the welding area and as protection for the condenser lens 5 from welding vines.

In order to obtain a good weld bead, it is necessary to increase the diameter of the nozzle 3 and to slow the flow rate of the shielding gas to the same level as in TIG welding. However, when the aperture of the nozzle 3 is increased, the shielding gas cannot sufficiently prevent the snow ivy from entering the processing head body 1, and the snow/JF ivy adheres to the exit surface 5a of the condenser lens 5. This causes a problem that the irradiation intensity of the laser beam 4 decreases. In addition, when the diameter of the nozzle 3 is made smaller, the flow velocity of the shielding gas ejected from the nozzle 3 increases, so the condensing lens 5 can be sufficiently protected from snow ivy. , and the shielding gas at a high flow rate entrains air, resulting in a problem that the shielding of the welding location becomes insufficient.

The present invention has been made in view of the above-mentioned circumstances.It is an object of the present invention to provide a laser welding device that can sufficiently protect a condensing lens from snow ivy and can supply shielding gas at a stable flow rate to a welding location. That is.

In order to achieve the above object, the present invention provides a lens protection nozzle that allows a high-flow gas to cross the optical axis of a condensing lens and flow out in the form of a film, and also provides a low-flow seal gas near the focal point of the laser beam. This is characterized by the provision of a shielding gas supply nozzle that flows out the shielding gas.

Hereinafter, one embodiment of the present invention will be described in detail with reference to the drawings.

FIG. 2 is a sectional view of the distal end of the device showing an embodiment of the present invention, and FIG. 3 is a sectional view taken along line T-1 in FIG. Note that the same parts in FIG. 1 as in FIG. 1 are given the same reference numerals.

In FIG. 2, at the tip of the processing body 1, a lens protection gas such as air or nitrogen is flowed out in the form of a film at a high flow rate across the optical axis of the condensing lens 5 from a nozzle hole 21 provided on the inner surface. A lens protection nozzle 21 is attached to protect the condenser lens 5 from spatter during welding. For example, as shown in FIG. 3, the nozzle hole 21m of the lens protection nozzle 21 has a substantially fan-shaped planar shape, so that the lens protection gas covers the entire lens surface of the condenser lens 5. ing. In addition, a shield supply nozzle 22 is provided near the focal point 4a of the laser beam 4 to supply shield gas such as argon gas to the welding location of the workpiece at a relatively slow external flow velocity. Gas supply7. The connecting portion tsrtc is connected and fixed to the main body 1.

Note that cylinder number 24 in FIG. 1 is a gas supply port for supplying lens protection gas to the lens protection nozzle 2. Further, the opening 21b of the lens protection nozzle 21 is set to be large so that the lens protection gas flowing out from the nozzle hole 21a flows out to the outside in a gentle flow.

In this way, according to this embodiment, the protection of the condenser lens 5 and the shielding of the welding area are performed separately using the lens protection nozzle 21 and the shielding gas supply nozzle 22, so that welding can be performed without being affected by the diameter of the nozzle. The condensing lens 5 can be protected from dust and ivy, and shielding gas at a stable flow rate can be supplied to the welding location.

Note that the present invention is not limited to the above embodiments.
For example, the nozzle hole 21 & of the lens protection nozzle 21 is
It may have a planar shape as shown in the figure, or it may have a nozzle hole directly on the inner surface of the processing head body 1 below the condenser lens 5.
J& may also be provided.

As described above, according to the present invention, by providing a lens protection nozzle at the tip of the device that allows high-velocity gas to cross the optical axis of the condensing lens and flow out in the form of a film, a high-velocity gas flows out in the vicinity of the focal point of the KL/-the beam. Since the structure is equipped with a shield gas supply nozzle that discharges shield gas at a flow rate, it is possible to provide a laser welding device that can sufficiently protect the condenser lens from stubble ivy and can supply shield gas at a stable flow rate to the welding location. .

[Brief explanation of the drawing]

Figure 1 is a sectional view showing the tip of a conventional laser welding device;
FIG. 2 is a sectional view of the tip of the device showing an embodiment of the present invention;
3 is a sectional view taken along the line II in FIG. 2, and FIG. 4 is a sectional view showing a modification of the nozzle hole. 1... Processing head body, 5... Condensing lens, 21.
...Lens protection Fl nozzle, 22...Shield gas supply nozzle. Applicant's sub-agent Patent attorney Takehiko Suzue$1 Figure 2 Figure 3 Figure 1 Figure 4 1

Claims (1)

[Claims] In a radar welding device that performs laser welding by focusing a laser beam using a condensing lens installed in the tip of the device and irradiating it onto the surface of a workpiece, a shielding gas is supplied to the surface of the workpiece. A lens protection nozzle that crosses the optical axis of the condensing lens and flows out in a film form is provided at the tip of the device, and a shield supply nozzle that flows out a low-flow shielding gas near the focal point of the laser beam is provided. Characteristic laser welding equipment.