JPH11320152A - Method and facility for continuous welding by laser beam in longitudinal direction of steel belt - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a method and facility for welding a steel belt in a longitudinal direction with a laser beam which can produce a wide belt-formed steel plate with good quality at low cost and high productivity by butting edges of the welding side of both belt-formed steel plates without a gap and restraining deformation, especially of a weld zone when the belt-formed steel plates are continuously welded in a longitudinal direction. SOLUTION: After transferring faces of one belt-formed steel plate 11 and the other belt-formed steel plate 12 are converged on the same plane before the pass restraint, both edges on the tack welding side of the belt-formed steel plates 12 and 11 are butted without a gap. Then, they are pass-restrained and tack-welded at a small power, and introduced to a following final welding process 32 under the condition that the belt-formed steel plates 11 and 12 are surely fixed without deformation. Furthermore, both ends of the tack welded belt-formed steel plates are guided by a side guide and pass-restrained, so as to final-weld the tack welded portion at a regular power.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a method and apparatus for continuously welding a steel strip in the longitudinal direction by, for example, laser beam welding. In particular, when steel sheets of different types (thickness, material, etc.) are used for adjacent parts, such as an automobile body, a joining blank capable of integrally forming these parts is required. The present invention
The present invention relates to a method and a welding apparatus for longitudinally welding strip steel sheets which can be manufactured at low cost and with high productivity by continuously welding a plurality of strip steel sheets in the longitudinal direction to produce the joining blank material and the wide welding strip steel sheet at low cost. is there.

[0002]

2. Description of the Related Art In order to produce the above-mentioned joint blank material, there is a method of welding strip-shaped steel plates (sheets) to each other. In this method, there is known a method in which side edges of a sheet are arranged in abutting manner, tightened to eliminate a gap in the abutting portion, and a welding machine is moved along the abutting edge during welding. In addition, there is also a method of welding strip-shaped steel sheets. In this method, both the strip-shaped steel sheet and the welding machine are moved. However, since the strip-shaped steel sheet cannot be transported continuously in the welding equipment, the welding length is long. Is limited by the travel of the welding machine.

As described above, in the prior art, the above-mentioned known method and apparatus cannot be used in a welding machine for continuously welding strip-shaped steel plates in the longitudinal direction. In this case, welding can be performed only with a sheet, resulting in an increase in cost and a reduction in productivity.

In recent years, various improvements have been made, and
As disclosed in Japanese Patent No. 3153, the welding machine is fixed, and the belt-like steel plate is conveyed in a state where the side ends of the steel plate are abutted to the welding position, thereby continuously welding the steel belt with a laser beam. A conveying and guiding method is disclosed. That is, as shown in FIGS. 15 and 16, the welding-side side ends of the strip-shaped steel plates a and b are adjacent to each other, and one of the side ends is the guiding surface of the guiding members c and b in the same vertical plane. A method for conveying and guiding a strip-shaped steel sheet to be fed to a welding machine e by contacting them on the same plane without any gaps on separate conveying surfaces arranged side by side with each other and inclined at an acute angle α is disclosed.

In this method, the side ends of the strip-shaped steel plates a and b which are conveyed vertically apart from each other are pushed in by a slanted conveying roller r and a vertical roller g to form a welded side end. These are brought into contact with the guide surfaces ca, da of the guide members c, b on the same vertical plane, conveyed, converged by the grip roller f, and the side ends of the strip-shaped steel plates a, b are butted against each other. With this configuration, when welding with laser beam welding at normal power suddenly, a sudden amount of heat is supplied at once. In some cases, there is a problem that the properties of the obtained welded part are deteriorated. In particular, the problem becomes more apparent as the thickness difference between the abutted strip-shaped steel plates increases.

[0006]

DISCLOSURE OF THE INVENTION The present invention advantageously solves the above-mentioned problems when continuously welding strip-shaped steel sheets in the longitudinal direction, so that the welded side ends of the strip-shaped steel sheets can be welded without gaps. Butt, in particular, welding without deformation of the welded part, continuous welding method by laser beam in the longitudinal direction of the strip steel plate, which can produce good quality wide width welded strip steel sheet at low cost and high productivity, and The purpose is to provide a continuous welding facility.

[0007]

Means for Solving the Problems In order to achieve the above object, the present invention has the following features. That is, (1) abut the side edges of the strip-shaped steel plate adjacent in the width direction,
A method of continuously welding a strip-shaped steel sheet in which the butted portions are continuously welded by a laser beam in a longitudinal direction, wherein one strip-shaped steel sheet and the other strip-shaped steel sheet adjacent in the width direction are conveyed in parallel at different conveyance angles to form one strip-shaped steel sheet. The transfer surface of the steel sheet and the other strip-shaped steel sheet converge so as to be in the same plane immediately before the welding position, and in the same plane after the convergence position,
The welded side end of the other strip-shaped steel sheet and the welded side end of the other strip-shaped steel sheet are continuously butted and restrained, and the butted portion is temporarily welded by a temporary welding device with a small power. On both sides of the temporarily welded strip-shaped steel sheet composed of one strip-shaped steel sheet and the other strip-shaped steel sheet obtained by the above-mentioned temporary welding, the paths are restrained while being guided by side guides, and the temporary welded portion is subjected to regular power by the present welding device. A continuous welding method using a laser beam in the longitudinal direction of a strip-shaped steel plate, which is characterized by performing actual welding.
and

(2) A continuous welding apparatus for a strip-shaped steel sheet in which one of the strip-shaped steel sheets adjacent to each other in the width direction and the other strip-shaped steel sheet are butted on the welding side, and the butted portion is continuously welded in a longitudinal direction by a laser beam. Converging function to convey one strip steel sheet and the other strip steel sheet adjacent in the width direction in parallel, converge just before the temporary welding position, and make the conveyance surface of one strip steel sheet and the other strip steel sheet in the same plane. And a guide device for abutting the side end of one strip-shaped steel plate and the welded side end of the other strip-shaped steel plate, a path constraint device for path-constraining one strip-shaped steel plate and the other strip-shaped steel plate, A temporary welding process including a temporary welding device for temporarily welding the strip steel plate and the other strip steel plate, and a temporary welding process that is provided at a subsequent stage of the temporary welding device and includes a strip steel plate that is temporarily welded by the temporary welding device and the other strip steel plate. Carry the welded strip steel plate Transfer device, a pair of side guides for guiding both side ends of the welded strip, a path restraining device for restraining the welded strip, and a full welding process of the temporarily welded portion of the temporarily welded strip with regular power. This is a continuous welding facility using a laser beam in the longitudinal direction of a strip-shaped steel plate, which comprises a main welding step equipped with a device.

[0009]

DETAILED DESCRIPTION OF THE INVENTION The present invention provides a temporary welding step in which one strip steel sheet and the other strip steel sheet are temporarily welded continuously with a small power in the longitudinal direction, and a temporary welding step subsequent to the temporary welding step. A strip steel plate that is used when manufacturing a wide welded strip steel plate consisting of one strip steel plate and the other strip steel plate, consisting of a main welding process in which the temporarily welded strip steel plate obtained by temporary welding is continuously welded with regular power. Continuous welding method and continuous welding equipment using a laser beam in the longitudinal direction.

According to the present invention, in the temporary welding step, the conveying surfaces of one strip-shaped steel sheet and the other strip-shaped steel sheet are converged on the same plane before the path is constrained, and then the side of the other strip-shaped steel sheet on the side of the temporary welding side. After pressing the end of the temporary welding side of the one strip-shaped steel sheet by pressing the side end of the one strip-shaped steel sheet without any gap, the path is restrained and then temporarily welded with low power. In the state where the strip-shaped steel sheet is securely fixed without deformation, it is guided to the subsequent main welding process, the sides of the temporary welded strip-shaped steel sheet are guided by side guides, path-constrained, and the temporary welded part is fully welded with regular power. .

According to the present invention, the main welding is performed at normal power in a state in which one of the strip-shaped steel sheets and the other strip-shaped steel sheet are securely fixed without deformation by low-power temporary welding. It is possible to stably secure a good welded portion without occurrence, and it is possible to obtain a wide-width welded strip having good welded properties consisting of one strip-shaped steel sheet and the other strip-shaped steel sheet with high productivity. It is.

Here, the small power is a power of about 2/3 to 1/2 of the normal power. In the case of less than 1/2 of the regular power, welding cannot be performed sufficiently,
Peeling occurs during the transport process, or the film cannot be tolerated by the deformation effect of the main welding and peels off. In the case of more than 2/3 of the regular power, the deformation is lighter than in the case of the regular power,
In some cases, deformation may occur and the cost burden may increase, so that the significance of welding in two stages may be reduced.

[0013] When butting one strip-shaped steel sheet and the other strip-shaped steel sheet in the same plane, a guide device or a transfer device can be used. Further, a roll, a pressing body, or the like can be used for the path constraint after the butting.

[0014] pre-welded devices are those which have a structure capable of controlling the power may be a typical welding apparatus, but enables high-speed welding, broad be applied width in the welding of different materials, CO ₂ A laser beam welding machine using a YAG laser is preferable. The welding line in this case may be formed intermittently.

The temporary welding position of this temporary welding device is such that the side end of one of the strip-shaped steel plates on the side of the temporary welding is maintained at a fixed position on a plane perpendicular to the conveying direction of the strip-shaped steel plate by the cooperation of the guide devices. It should just be. Basically, it may be moved or fixed in the transport direction and the width direction of the strip-shaped steel sheet during welding. When fixed, the moving mechanism of the temporary welding device can be omitted or simplified, and the structure of the welding device can be simplified.

The side guide used in the main welding step may be basically the same as the guide device in the temporary welding step. The present welding device is capable of welding at a higher speed than other welding means, and has a wide application range even in welding between dissimilar materials.
A laser beam welding machine using an O ₂ , YAG laser is preferred.

When the present invention is applied, the conveying surface of the strip-shaped steel plate to be welded is mainly a horizontal surface in the width direction, but may be a vertical conveying surface or an inclined conveying surface. In the longitudinal direction, in the process of reaching the convergence device, one of the one strip-shaped steel sheet and the other strip-shaped steel sheet at least partially forms an inclined conveyance surface, and after the convergence position, in the width direction. The horizontal transport surface is the mainstream, but may be a vertical transport surface or an inclined transport surface.

[0018]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS An embodiment of the present invention will be described with reference to FIGS. This embodiment shows a case where the strip-shaped steel sheets to be welded are of the same steel type and have the same thickness. Figure 1 is a drawing showing an example of the welding equipment in the longitudinal direction of the steel strip to continuous welding of the present invention, this example, uncoiler 2 _1, 2 ₂ in the steel strip of Article 2 mounted in the coil 1 _1, 1 ₂ unwinding, the temporary welding apparatus (laser beam welding machine) 3 ₁ the temporary welding process Aw with a steel strip 1 ₁ is temporarily welded to the steel strip 1 ₁ and the steel strip 1 ₂ in the longitudinal direction, and welding the steel strip 1a consisting of 1 _2, the welding apparatus (laser beam welding machine) 3 ₂ led to the welding process Bw with, the welding device 3
_The temporary weld is fully welded in Step 2 and the two strip steel plates 1 ₁ , 1 ₂
And is cut into a predetermined size by the output shear 4 to produce a wide-width welded steel plate 1c.

First, the temporary welding step Aw will be described in detail with reference to FIGS. 2 strip steel plates 1 ₁ and 1
₂ is an uncoiler 2 ₁ , 2 ₂ which is located vertically away
After being guided by the entry side shears 6a and 6b via the outlet devices 5a and 5b, the defective portion of the head is cut and the shape is corrected by the levelers 7a and 7b, the strip-shaped steel sheet passes through the free loops 8a and 8b. 1 ₁ transport roller 9a,
9b, the 9c, also the steel strip 1 ₂ transport roller 9d, 9e, by 9f, gradually approaches at different angles from a state in which each spaced vertically, just before the path restraint apparatus 10 comprising a pair of upper and lower idle rolls , acute α is formed between the steel strip 1 _1, 1 ₂ of the conveying surface, being parallel transported as converged in the same plane without overlapping.

In the parallel transport process, the strip steel plate ₁₁
As shown in FIG. 5 provided on the upstream side of the convergence position, a is brought into contact with the guide surfaces 12a and 13a of the vertical roll type guide devices 12 and 13 having the reciprocating mechanism 11 so that the side on the temporary welding side is used here. The end is guided on an extension of the temporary welding position. On the other hand, the steel strip 1 ₂ is immediately before the convergence position, for example as shown in FIG. 6 provided on the counter-welding side of the steel strip 1 _2, the guide surface of the vertical roll-type guide device 14 having a forward and reverse mechanism 15 1
4a presses the side end on the non-welding side,
Side end of the pre-welded side is pressed against the side edge of the steel strip 1 ₁ welded-side, above the convergence position, the steel strip 1 side edge of _one of the welding side and the steel strip 1 ₂ tentative welding side of the side edge are the same Matched in a plane.

In this state, the path is restrained as shown in FIG. 7 by applying a tension by the path restraining device 10 disposed immediately afterward, and a belt-like shape is formed in a state in which the occurrence of displacement between the welding-side side ends is prevented. side edge of the side edge of the steel plate 1 ₁ of the welded-side and the steel strip 1 ₂ weld side is arranged immediately after the path constraining device 10, longitudinally continuous small power by the temporary welding device 3 ₁ having a power control structure and is temporarily welded wa, pre-welded steel strip 1a made of a strip-shaped steel plate 1 ₁ and the steel strip 1 ₂ is obtained continuously. The temporary welding steel strip 1a consisting of pre-welded wa been the steel strip 1 ₁ and the steel strip 1 ₂ small power the temporary welding process,
It conveys to the main welding process Bw following the temporary welding process Aw.

Next, the main welding process will be described with reference to FIGS.
4 will be described. The temporarily welded strip-shaped steel plate 1a from the temporary welding process Aw is transported through the free loop 16 to the transport roller 1
7a and 17b, a pair of vertical roll-type rolls having an advancing / retracting mechanism 21 as shown in FIG. 12 at both ends so that the temporary welding wa portion is located on an extension of the main welding position. Guide surfaces 18a of the side guides 18, 19,
And guided by 19a, the temporary welding portion wa with path constrained to 13 under tensioning path constraining rolls 20 placed immediately after, the welding apparatus using a laser beam arranged immediately 3 ₂ by by this welding wb continuously longitudinally regular power, it is possible to obtain a weld steel strip 1b of the wide consisting of the steel strip 1 ₁ and the steel strip 1 ₂ as shown in FIG. 14. This wide welded strip steel plate 1
b is measured to a predetermined length by the output side shear 4 and loaded on the pallet 22 as a wide-width welded steel plate 1c.

In the present invention, as described above, the side ends of the strip-shaped steel sheets to be temporarily welded do not overlap with each other or rise up to form a gap. The main welding is performed after being securely fixed by temporary welding.

Therefore, it is possible to reliably and stably perform the main welding, and to obtain a high-quality wide-width strip-shaped welded steel sheet made of two or more high-quality strips of the same or different types at high productivity. This can be measured to a predetermined size to obtain a wide strip steel plate.

The present invention is not limited to the above embodiment. The two strip-shaped steel plates to be welded may be of different steel types or of different thicknesses. In addition, the structure, arrangement, and number of the transfer device, the structure of each guide device, the guide position, the temporary welding position, the main welding position, the side guide, the path restraining device, the temporary welding device and the main welding device, which constitute the present invention. Can be changed within the technical range that satisfies the claims described above, depending on the steel type, size, number of strips, welding conditions, equipment arrangement, and the like of the strip-shaped steel plate to be welded.

[0026]

According to the present invention, the welding side edges of the strip-shaped steel plate to be welded are securely butted with no gap by using the guide device, and the abutted side edges are reduced in power with the path restrained. After temporary welding and fixing without deforming, the temporary welding part was guided to the main welding position by the side guide, and the temporary welding part was continuously welded with regular power. Can be welded more reliably without dislocation, and a wide band-shaped welded steel plate of good quality with good weld properties without deformation of the weld can be obtained with high productivity.

[Brief description of the drawings]

FIG. 1 is an overall explanatory view showing an embodiment of a continuous welding facility of a strip-shaped steel plate of the present invention using a laser beam in a longitudinal direction.

FIG. 2 is an explanatory view of a temporary welding step in FIG. 1;

FIG. 3 is a partially enlarged side view illustrating a process of guiding a strip-shaped steel sheet to be welded to a welding facility in the temporary welding step of FIG. 2;

FIG. 4 is an explanatory plan view of FIG. 3;

FIG. 5 is an enlarged cross-sectional explanatory view taken along the line Aa-Ab in FIG. 4;

FIG. 6 is an enlarged cross-sectional explanatory view taken along the line Ba-Bb in FIG. 4;

FIG. 7 is an enlarged cross-sectional explanatory view taken along the arrow line Ca-Cb in FIG. 4;

FIG. 8 is an explanatory plan view of a welded strip steel plate obtained by laser beam welding in the longitudinal direction in a temporary welding step.

FIG. 9 is an explanatory view of the main welding step in FIG. 1;

10 is a partially enlarged side view illustrating a process of guiding a strip-shaped steel sheet to be welded to a welding facility in the main welding step of FIG. 9;

FIG. 11 is an explanatory plan view of FIG. 10;

FIG. 12 is an enlarged cross-sectional explanatory view taken along the line Aa-Ab in FIG. 11;

FIG. 13 is an enlarged cross-sectional explanatory view taken along line Ba-Bb in FIG. 11;

FIG. 14 is an explanatory plan view of a wide welded strip steel plate obtained by laser beam welding in the longitudinal direction in the main welding step.

FIG. 15 is an explanatory plan view showing a process of guiding a strip-shaped steel sheet to be welded to a welding apparatus in the conventional example of the conventional continuous welding apparatus for a strip-shaped steel sheet in FIG. 2 in the longitudinal direction.

FIG. 16 is an explanatory side view of FIG. 10;

[Explanation of symbols]

1 _1, 1 _2, 1 _3: steel strip 1a: Welding the steel strip 1b: broad welding steel strip 1c: wide welding steel plate 2 _{1, 2} 2, 2 _3: uncoiler 3 _1: temporary welding apparatus (laser beam welding machine) 3 ₂ : Main welding device (laser beam welding machine) wa, wb: welding 4 shear 5a, 5b: outlet device 6a, 6b: shear 7a, 7b: leveler 8a, 8b: free loop 9a to 9f: transport device (roller) 10 : Path restraining device (roller) 11: Advance mechanism 12, 13: Guide device 12 a, 13 a: Guide surface 14: Guide device 14 a: Guide surface 15: Advance / retreat mechanism 16: Free loop 17 a, 17 b: Transport device (roll) 18, 19: side guide 18a, 19a: guide surface 20: path restraining device (roll) 21: advance / retreat mechanism (side guide) 22: pallet

Claims (2)

[Claims] 1. A continuous welding method for a strip-shaped steel sheet in which side edges of strip-shaped steel sheets adjacent in a width direction are butted, and the butted portion is continuously welded in a longitudinal direction by a laser beam.
(1) One strip steel sheet and the other strip steel sheet adjacent in the width direction are conveyed in parallel at different conveyance angles, and the conveyance surfaces of one strip steel sheet and the other strip steel sheet are in the same plane immediately before the welding position. In the same plane after the convergence position, the welded side end of the other strip-shaped steel sheet and the welded side end of the other strip-shaped steel sheet are continuously butt-constrained, and the butt portion is temporarily welded. Temporary welding with small power by the device.
(2) Both sides of the temporarily welded strip steel sheet composed of the one strip steel sheet and the other strip steel sheet obtained by the temporary welding in (1) are path-constrained while being guided by a side guide, and the temporary weld portion is fully welded. A continuous welding method using a laser beam in the longitudinal direction of a strip-shaped steel plate, wherein the main welding is performed with a regular power by an apparatus. 2. A continuous welding apparatus for a strip-shaped steel sheet in which one of the strip-shaped steel sheets adjacent to each other in the width direction and the other strip-shaped steel sheet are joined to each other on the welding side, and the butt portion is continuously welded in a longitudinal direction by a laser beam. (1) One strip steel sheet and the other strip steel sheet adjacent in the width direction are conveyed in parallel and converged immediately before the temporary welding position so that the conveyance surfaces of the one strip steel sheet and the other strip steel sheet are in the same plane. A conveying device having a convergence function, a guide device for abutting a side end of one strip-shaped steel plate and a side end on a welding side of the other strip-shaped steel plate, and a path constraint device for path-constraining the one strip-shaped steel plate and the other strip-shaped steel plate. A temporary welding process including a temporary welding device for temporarily welding one of the strip steel plates and the other strip steel plate; and (2) a temporary welding device,
A transport device that transports a temporarily welded strip made of the strip steel sheet temporarily welded by the temporary welding device and the other strip steel sheet, a pair of side guides that guide both side ends of the welded strip steel sheet, and path-constraining the welded strip steel sheet. A continuous welding facility using a laser beam in the longitudinal direction of a strip-shaped steel plate, comprising a main welding process including a path restraining device and a main welding device for main-welding a temporary welded portion of the temporarily-welded strip-shaped steel plate at a normal power.