JPS6167588A - Laser beam butt welding equipment - Google Patents

Abstract

PURPOSE:To obtain a titled equipment for executing a good welding irrespective of a plate thickness difference by holding the preceding and following strips by the upper fixed clamps, respectively, by making the lower clamp ascend, maintaining the joint part by a back bar so that the surface becomes a uniform height, and keeping a height of a laser torch constant. CONSTITUTION:The preceding and following strips 1, 1' are held by the upper fixed clamps 2, 2' by making the lower clamps 3, 3' ascend. Also, the joint part is maintained by an ascent of a back bar 14 so that the surface of the strip becomes a uniform height. A laser torch 7 provided on the upper fixed clamp 2 always maintains a prescribed height against a weld zone, and since there is no step difference on the surface of the weld zone, welding is executed satisfactorily.

Description

DETAILED DESCRIPTION OF THE INVENTION (Industrial Application Field) The present invention relates to a laser butt welding device, and the technology described in this specification is applicable to a device in which a welding line for setting a filler wire is always maintained horizontally. The present invention proposes a device that can be suitably used to perform welding with excellent weld strength due to its configuration.

(Prior Art) In butt welding of strips using a laser beam using a filler wire, the strips are sheared and then butted together with a slight welding gap, and welding is performed while supplying the filler wire into the gap. In this case, the laser beam diameter at the welding surface is 0.2 to 0.8"φ and the gap is about 0.1 to 0.7B, but the filler wire to be supplied should have a larger diameter than the gap. Is it normal to use 0 conventionally? ) The laser welding device is equipped with an exit clamp device for clamping the tail end of the leading strip and an entry clamp device for clamping the leading end of the trailing strip, and the welding line of the protruding ends of both strips is It is common to have a structure in which a laser torch is provided on the upper side along the line, and a back bar is provided on the lower side.

Using this conventional device, the leading and trailing stages are conveyed.
When butt welding the tail end and tip of an IJ tube, each end is first firmly clamped with a clamp mechanism, and then a laser beam torch is run along the cutting line. The upper clamp located at the top moved up and down to clamp each end of the strip. Moreover, the filler wire is fed along the gap of the welding line by the feeding motor, but since strict precision is required for the feeding position, it is impractical to provide a feeding guide to guide the filler wire. The way of guiding is shown in Figure 4-(b).
This involved selecting an angle that would set the strip surface just before it was hit by the laser beam, and feeding it along the gap between the tip and tail of the strip.

(Problems to be Solved by the Invention) In the case of such conventional welding equipment, high feeding accuracy is required, so when welding strips with different thicknesses, for example, the feed position of the filler wire is shifted from the center of the gap. Due to the slight deviation, the filler wire was not melted properly by the laser beam, and a weld with high welding strength could not be achieved.

(Means for Solving the Problems) The present invention provides an exit side clamping device for clamping the tail end of the leading strip and an IJ tube as a means for overcoming the problems of the prior art described above. A metal strip laser is provided with an entry side clamping device for clamping the tip of the metal strip, and a laser torch is provided on the upper side along the welding line of the butt ends of both IJ knobs, and a back bar is provided on the lower side. In the butt welding device, the upper clamp of each of the clamp devices has a fixed structure, while the lower clamp has a structure that can be raised and lowered, and the back bar is configured to be raised and lowered independently on the entry and exit sides. We propose a laser butt welding device that uses laser butt welding.

(Function) As can be seen from FIG. 1, in the present invention, the upper clamp has a fixed structure and the lower clamp is pushed up to clamp the strip, and the back bar that presses down the lower strip. Adopts a structure in which the leading and trailing strip sides move separately (equalizers such as springs are installed as necessary to ensure that even and sufficient pressing force is applied even when the plate thickness is different). And since each upper clamp and the laser torch travel frame are integrated, the laser torch's vinyl condenser (lens) and the surface of the plate (lower surface of the upper clamp)
The distance between the filler wire and the filler wire can be maintained constant, and the position where the filler wire touches the plate surface can also be kept constant.

Particularly in the case of the present invention, when welding IJ tubes with different thicknesses, the top surfaces of the leading and trailing strips are at the same level and match, as shown in Figure 1-(b), so the filler wire is Centering can also be reliably guided to the center of the weld line (gap), eliminating deviation from the laser beam center.
Effective in achieving welds of sufficient strength.

Furthermore, even in the case of butt welding that does not use filler wire, if the plate thicknesses are different, the top surface positions of the leading and trailing strips will change, and the one farther from the focus will be less likely to melt, but in the case of the present invention The positions of their upper surfaces can always be matched and sufficient welding strength can be obtained.

(Example) Fig. 1 shows a preferred embodiment of the laser butt welding bag "2" of the present invention, and the features of this device will be explained in comparison with Figs. 2 to 4, which are shown as examples of conventional devices. do.

The symbols 1 and 1' in the figure indicate leading and trailing IJ knobs, 2 and 2' are upper clamps, and 3.3' are lower clamps, and in the case of the present invention, the upper part is a fixed type. In contrast to the conventional example (FIG. 2) in which the lower part is moved up and down by a clamp cylinder 4.4', the lower part is fixed and the upper part is movable. Reference numeral 5 in the figure denotes a laser torch traveling frame, which in the present invention is integrally attached with a fixed rod 5a extending from the fixed upper clamp 2, but in the conventional example, it is supported separately from the upper lamps 2p and 2p'. Ru. 6
is the laser torch lifting motor, 7 is the laser torch, 8
9 is a filler wire, 9 is a filler wire feeding motor, 10, 101) are back bars for the strip ball presser, and the back bar 10 of the present invention includes a leading plate hack bar 13 and a trailing plate back bar 14, which are cylinders for the back bar. 1
2, when moving through the rod 11, the
As shown in b), the strip can be moved up and down separately depending on the plate IJ, and can be firmly fixed despite variations in the thickness of the strip. In the figure, 15 is a back bar equalizer that is effective when the plate thicknesses are different, 16 is a laser beam, 17 is a laser beam condenser, and 18 is a filler wire feeding guide.

As is clear in this example, namely FIG.
As can be seen from the comparison between BL and Figures 4 (a) and (b), there is a noticeable difference in the effect when the thickness of the leading and trailing strips is different, making it possible to perform laser beam welding with excellent welding strength. It is effective to employ the device of the present invention.

(Effects of the invention) As can be seen from the above explanation, when comparing the conventional laser welding device and the welding device of the present invention, there is a significant difference in welding, especially when the plate thickness is different, and this is shown in Fig. 5. As is clear from the graph of the number of repeated bending shown (indicating the strength of the welded part when the plate thickness difference is 30%), the strength of the present invention is approximately four times greater than that of the conventional method. In addition, there are significant differences in plate thickness, for example, cyclic bending strength of 10
In order to obtain ~20 times, the difference in plate thickness is 10 to 2 in the case of conventional equipment.
It remains at 0%, and the strength varies depending on the breed depending on how the filler wire is inserted. On the other hand, with the device of the present invention, sufficient strength can be obtained for plate thickness differences of 50 to 60 mm.
Moreover, it has the effect that the variation in strength is small.

[Brief explanation of the drawing]

Fig. 1 shows an example of the laser butt welding device of the present invention, in which (a) is a front view, (b) is a front view of the ball presser back bar, Fig. 2 is a front view of the conventional device, and Fig. 3 The figure is a front view showing the filler wire supply state, Figure 4 is a welded cross-sectional view, (a) is a cross-sectional view when the plate thickness is the same, (b) is a cross-sectional view when the plate thickness is actual, and Figure 5 is a cross-sectional view of the present invention and conventional It is a graph of the number of repeated bending showing the difference in the effect of technology. 1. Leading strip 1'... Trailing strip 2,
z'...Top clamp 3, 3'...Bottom clamp 4.
4' Clamp cylinder 5 Laser torch traveling frame 6 Laser torch lifting motor 7 Laser torch 8 Filler wire 9
...Filler wire feeding motor 10...Back bar 1 and banker push rod 12...Cylinder for back bar 13...Back bar t for leading plate...Back bar 15 for trailing plate...Back bar presser equalizer 16...Laser beam

Claims (1)

[Claims] 1. It is equipped with an exit side clamp device for clamping the tail end of the leading strip and an input side clamp device for clamping the tip end of the trailing strip, and a laser torch is installed on the upper side along the welding line of the butt ends of both strips. In a laser butt welding device for metal strips, the upper clamp of each of the above clamping devices has a fixed structure, while the lower clamp has a movable structure, so that the back bar can be inserted and removed. A laser butt welding device characterized in that it is configured to move up and down independently on the sides.