JPS6229147B2 - - Google Patents

Description

Detailed Description of the Invention [Objective of the Invention] (Industrial Application Field) The present invention relates to a welded object ( This invention relates to a laser seam welding machine that linearly performs seam welding of a workpiece with a constant beat length.

(Prior Art) In general, electric spot welding means pressurizes two superposed objects to be welded using a pair of upper and lower electrode tips, and instantaneously supplies a large current to the two objects to be welded. The joints are welded together by spot welding, which generates resistance heat.

(Problems to be Solved by the Invention) However, conventional electric spot welding means has restrictions on the thickness of the objects to be welded that can be mutually welded due to limitations in power supply capacity, and only one welding point (spot). If another spot weld is performed very close to the welding point), the current from this spot weld will be diverted to the spot weld that has already been welded, making it impossible to obtain an effective spot weld and reducing the reliability of the spot weld. There is a risk of harming sex.

In particular, in the above-mentioned spot welding means, 2
It is difficult to seam weld a continuous beat length of two overlapping objects to be welded in a straight line.

On the other hand, the spot welding method described above requires the instantaneous flow of a large current;
A highly flexible conductor must be used, which not only poses problems in terms of safety and the lifespan of the electrode chip, but also requires a large pressing force to bring the two objects to be welded into sufficient contact with each other in advance. Along with needing
When the object to be welded is a thin plate, molten metal mist and the like are often scattered in all directions during welding, and there is a risk that the number of welding points at the joint may be substantially reduced.

Furthermore, the double electrode chips used in the above-mentioned spot welding means must always be kept in a clean state in order to maintain electrical conductivity, cooling properties, and pressing force resistance.

On the other hand, some laser spot welding methods have already been proposed, but when the workpiece is a thin plate, these methods irradiate the workpiece with a laser beam from an oblique direction to weld the workpiece to substantially reduce the weld length. I'm trying to make it longer.

However, the above-mentioned laser spot welding means causes many blowholes and impurities to be mixed into the metal structure between the welded part and the welded part due to excessively rapid heating and rapid cooling during welding with laser beams. Furthermore, there is a risk that an excessive difference in hardness may occur, causing quenching of the metal or local material distortion and cracking of the metal structure.

In order to eliminate the above-mentioned drawbacks, the present invention performs seam welding with a constant beat length on the workpiece in a straight line without causing excessive heating and rapid cooling during welding by laser light. The present invention provides a laser seam welding machine whose purpose is to improve the reliability of seam welding work without adversely affecting the metal structure of a welded object.

[Summary of the invention]

(Means for Solving the Problems and Their Effects) The present invention includes a swinging ram equipped with a laser device that is pivotally mounted on the upper part of a machine frame having a horizontal arm, and a lower part of the ram that is attached to the end of the horizontal arm. A tip is provided, and an upper tip that presses a workpiece to be welded is vertically disposed on the swinging ram located directly above the lower chip, and the swinging member is integrated with the swinging ram above the upper chip. The rotating shaft is rotatably mounted, a reflector is installed obliquely on the swinging member so as to reflect the laser beam of the laser device downward, and the swinging member below the reflector is mounted on the swinging member. A condensing lens is attached so as to focus on the object to be welded to prevent excessive heating and rapid cooling caused by the laser beam and thereby to avoid affecting the metal structure of the object to be welded.

(Example) Hereinafter, the present invention will be described with reference to an illustrated example.

In FIGS. 1 to 3, reference numeral 1 indicates a substrate 2.
This is the machine frame placed above, and this machine frame 1 has
A horizontal arm rod 3 is substantially integrally provided, and a swinging arm lever 5 equipped with a laser device 4 is pivotally attached to the upper part 1a of the machine frame 1 by a support shaft 6 so as to be freely swingable. There is. Further, a cylinder device 7, such as a hydraulic cylinder device, is connected and provided between one side portion 1b of the machine frame 1 and the swinging ram 5. The swinging ram 5 is designed to be able to swing around a support shaft 6. Furthermore, at one end 3a of the horizontal arm rod 3,
A welded object 9 in which the lower chips 8 have different plate thicknesses
It is swingably provided by a support shaft 10 so that it can be placed and welded thereon. That is, one end 3a of the horizontal arm 3 forms a pair of arcuate embankments 3b, and the lower surface 8a of the lower tip 8 is mounted on the support shaft 10 so as to be able to slide onto the arcuate embankments 3b. The bottom surface 8a of the lower chip 8 is
The lower tip 8 is held horizontally by the elasticity of a coil spring 11 interposed between the lower tip 8 and the one end 3a. Further, in the lower chip 8, there are provided a water supply port 13 having a beak nozzle 12 for ejecting a cooling fluid such as cooling water, and a cooling fluid outlet 14, for example. The pedestal portion 8b of the lower chip 8 is internally cooled, and the fluid that has cooled the pedestal portion 8b is discharged from the discharge port 14. .

On the other hand, an upper tip 15 that presses the object to be welded 9 is vertically connected to the swinging lever 5 located directly above the lower tip 8 by a mounting member 16 such as a mounting bolt. The upper chip 15 is provided with an inert gas supply port 17 and an exhaust port 18.

Therefore, the inert gas flowing in from the air supply port 17 prevents oxidation of the welded portion 9a of the workpiece 9 during welding, and also prevents metal mist, spatter, etc. generated during welding from being absorbed by the condenser lens 26, which will be described later. This prevents the particles from adhering to the reflector 25.

On the other hand, a bracket 20 having a bearing 19 is provided at the free end 5a of the swinging lever 5 above the upper tip 15.
0, a drive motor 21 that rotates reversibly is installed. A fan gear 23 meshes with a pinion 22 mounted on the output shaft of the drive motor 21, and this fan gear 23 rotates integrally with a swinging member 24 mounted on the bearing 19. It is provided on the shaft 24a. Furthermore, the swinging member 24 includes:
For example, a reflector 25 such as a reflector is installed diagonally to reflect the laser beam from the laser device 4 downward, and the swinging member 24 below the reflector 25 has a condenser lens. 26 is attached so as to focus on the object 9 to be welded. Therefore, the laser beam from the laser device 4 can perform seam welding with a constant beat length on the workpiece 9 by swinging the reflector 25 of the swinging member 24. It's becoming like that.

Therefore, when two objects 9 to be welded are to be superimposed and welded, the objects 9 to be welded are placed on the pedestal portion 8b of the lower chip 8, and at the same time, the objects 9 are cooled from the injection nozzle 12 of the water supply port 13. Fluid is injected onto the pedestal part 8b to cool it. Fluid is injected into the pedestal part 8b to cool it. On the other hand, inert gas is injected from the air supply port 17 to exhaust metal mist and spatter generated during welding from the exhaust port 18, thereby creating an atmosphere that prevents oxidation of the welded portion 9a.

Next, by driving the cylinder device 7, the swinging ram 5 is rotated to the left around the support shaft 6, and the upper tip 15 integrated with the swinging ram 5 presses the workpiece 9. Fix it.

Further, by driving the drive motor 21 and the laser device 4 simultaneously, the pinion 21 of the drive motor 21 reciprocates, and the sector gear 23 meshing with the pinion 21 also reciprocates.
Therefore, the reflector 25 of the swinging member 24, which is substantially integral with the sector gear 23, performs a slow vibration motion. At this time, the laser beam from the laser device 4 is reflected downward by the reflector 25, passes through the condenser lens 26, and performs seam welding with a constant beat length on the workpiece 9a of the workpiece 9.

Note that even if there is a slight difference in wall thickness of the workpiece 9, the lower tip 8 can rotate around the support shaft 10, so it can be pressed smoothly and seam welded. It is now possible to apply.
Further, it goes without saying that the sector gear 23 can be seam welded by only forward movement.

Note that the design may be freely changed to use a concave mirror instead of the reflector 25 and condenser lens 26 of the above-described embodiment.

〔Effect of the invention〕

As described above, according to the present invention, the horizontal arm rod 3
A swinging ram 5 equipped with a laser device 4 is pivotally attached to the upper part of the machine frame 1 having 3a is provided with a lower end tip 8, and an upper tip 15 that presses the workpiece 9 to be welded is vertically disposed on the swinging lever 5 located directly above the lower tip 8. Swinging lever 5
A rotating shaft 24a integral with the swinging member 24 is rotatably mounted on the swinging member 24, and a reflector 25 is obliquely disposed on the swinging member 24 so as to reflect the laser beam of the laser device 4 downward, A condensing lens 26 is attached to the swinging member 24 below the reflector 25 so as to focus on the workpiece 9, so that seam welding with a constant beam length can be performed linearly on the workpiece 9. Not only can welding be carried out smoothly without any adverse effects on the metallographic structure of No. 9, but it is also easy to handle, and furthermore, since welding is performed with a preheating effect, blowholes and contamination of impurities can be prevented.

[Brief explanation of the drawing]

FIG. 1 is a front view of a laser seam welding machine according to the present invention, FIG. 2 is an enlarged sectional view showing essential parts of the present invention, and FIG. 3 is an enlarged sectional view taken along the chain line A-A in FIG. 2. It is. 1... Machine frame, 3... Horizontal arm rod, 4... Laser device, 5... Swinging lever, 7... Cylinder device,
8... lower chip, 9... object to be welded, 23... sector gear, 24... rocking member, 25... reflector, 2
6...Condensing lens.

Claims (1)

[Claims] 1. A swinging lever equipped with a laser device is pivotally mounted on the upper part of a machine frame having a horizontal arm lever, a lower tip is provided at the end of the horizontal arm lever, and a lower tip is provided directly above the lower tip. An upper tip that presses the object to be welded is vertically mounted on the swinging rod located at the upper tip, and a rotating shaft integrated with the swinging member is rotatably mounted on the swinging rod above the upper tip. A reflector is obliquely installed on this swinging member so as to reflect the laser beam of the laser device downward, and a condensing lens is attached to the swinging member below the reflector to focus the object to be welded. A laser seam welding machine characterized by being attached so as to tie together. 2. The laser seam welding machine according to claim 1, wherein a sector gear that reciprocates is mounted on the rotation axis of the swinging member. 3. The laser seam according to claim 1 or 2, characterized in that the lower chip is provided with a cooling fluid supply/exhaust port, and the upper chip is provided with an inert gas supply/exhaust port. Welding machine. 4. The laser seam welding machine according to claim 1, 2, or 3, wherein the lower tip is pivotally attached to the free end of the horizontal arm rod by a support shaft.