JPH11285875A - Method and equipment for continuously welding in longitudinal direction of strip steel by laser - Google Patents

Abstract

PROBLEM TO BE SOLVED: To ensure welding by setting a prescribed gap along the extension of the welding point between the edges on the welding side of each strip steel, on the separate transporting planes of the adjacent pieces of strip steel, and maintaining the prescribed gap even on the same transporting plane formed by converging each strip steel. SOLUTION: The strip steel 1a, 1b is transported by each transporting device 2a, 2b and, while the edge on the welding side of the steel each comes into contact with the guide face 3a, 3b of the horizontal guide for the transporting plane, the two pieces of the strip steel come close to each other with an acute angle formed mutually. The edge on the welding side of the strip steel 1a, 1b is each pressed against the guide face 3a, 3b by another horizontal guide 4a, 4b, which is provided with a pressing mechanism at the edge of the unwelding side of the strip steel 1a, 1b facing opposite to the guide face 3a, 3b. Thus, the edges on the welding ends are held closely to each other at a distance L (L>0), transported without overlapping or squeezing, and converged on the same plane immediately before a pass restraining device 5. Consequently, the edges of the welding ends are maintained at a prescribed distance L' (L'>0, L'<=L) apart.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a method and an apparatus for continuously welding a steel strip in a longitudinal direction by using a laser. In particular, like the body of a car,
When steel plates of different types or materials are used for adjacent portions, a joining blank capable of integrally forming these portions is required. The present invention relates to a welding method for easily supplying a blank material in which such different steel sheets are joined from a strip-shaped steel sheet at a high productivity and at a low cost, and a facility therefor.

[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.

[0003] In addition, there is also a method of welding strip-shaped steel sheets to each other. In this method, both the strip-shaped steel sheet and the welding machine are moved. However, since the strip-shaped steel sheet cannot be conveyed continuously through the welding equipment, welding is performed. The length 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 for a welding machine for continuously welding strip-shaped steel sheets in the longitudinal direction, and the production of a joining blank material for automobiles is not possible. However, welding can only be performed 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, a guide method for continuously welding a strip-shaped steel sheet is provided by fixing a welding machine and transporting the strip-shaped steel sheet to the welding position in a state where side edges of the strip-shaped steel sheet abut against each other. Proposed.

In other words, according to this publication, the strip-shaped steel sheets are conveyed in a mutually inclined manner in a state in which the strip-shaped steel sheets are adjacent to each other and each side end is in contact with the same vertical guide surface provided on the guide device. Each part is conveyed on a separate conveying surface so that it converges immediately before the welding execution position on the conveying path, and is brought into contact with the above-mentioned side end without any gap in the same plane formed by the conveying surface after the above-mentioned converging position. It clarifies the method of transporting and guiding strip-shaped steel sheets to be sent to Japan.

According to this method, a vertical roller is provided at a position facing the guide surface (the side opposite to the strip-shaped steel sheet), and the welded end of each strip-shaped steel sheet conveyed vertically is separated by welding. The side edge of the strip is pushed by a vertical roller, brought into contact with the guide surface on the same vertical plane, and conveyed. At the convergence position, the side edges of each strip are abutted without gaps. Since the part is not necessarily flat, it has minute irregularities, so the gap may rather widen at the convergence position, or the side edges may be opposed to each other. In some cases, it may not be possible to obtain a proper welded portion, or it may not be possible to feed a strip-shaped steel plate smoothly.

[0008]

SUMMARY OF THE INVENTION The present invention has been made to solve the above-mentioned problems, and is intended to solve the problem described above. It is an object of the present invention to provide a method and equipment for reliably welding while maintaining a constant gap, and in particular, to provide a joining blank material for automobiles at low cost and with high productivity.

[0009]

Means for Solving the Problems In order to achieve the above object, the present invention has the following features. (1) The strip-shaped steel plates adjacent to each other are transported on different transport surfaces in a state where they are mutually inclined at an acute angle α as an elevation angle viewed in the direction opposite to the transport direction, and the welding execution position on the transport route In the method of converging immediately before to form the same transport plane and continuously welding the welded end of each strip-shaped steel sheet by laser, the strip-shaped steel sheets are conveyed to each other on the transport surface, respectively, on the welded side. The ends are conveyed at a constant distance L (L> 0), and the ends on the side to be welded are fixed at a constant distance L ′ in the same conveyance plane formed after the convergence position on the conveyance path. (L ′> 0, L ′ ≦ L) and a method for continuously welding the strip-shaped steel plate in the longitudinal direction by a laser, wherein the side ends of the welded ends are laser-welded.

(2) The laser according to the above item (1), wherein the distance L 'between the side ends of the strip-shaped steel plates to be welded in the same transport plane formed after the convergence position is 5 to 50 μm. Continuous welding in the longitudinal direction of the strip-shaped steel sheet.

(3) The adjacent strip-shaped steel plates are conveyed in a state where they are mutually inclined at an acute angle α as an elevation angle viewed in the direction opposite to the conveyance direction, and converge immediately before the welding execution position on the conveyance path. Transfer devices (2a, 2a,
2b), in a facility for continuously welding a strip-shaped steel plate in a longitudinal direction by a laser having the above-mentioned transfer devices (2a, 2).
b) a transverse guide device having guide surfaces (3a, 3b) in contact with the side edges of the strip-shaped steel plates on the side to be welded, and the respective guide surfaces (3a, 3b). Are arranged at a constant interval L (L> 0), and the side ends on the welding side are fixed at a constant interval L '(L') in the same transport plane formed after the convergence position on the transport path. > 0, L '
≦ L), and the side ends of the welded ends are laser-welded to each other.

(4) The distance (L ') between the side ends of each of the strip-shaped steel plates to be welded in the same transport plane formed after the convergence position is set to 5 to 50 μm. Equipment for continuous welding in the longitudinal direction of a strip steel plate by laser.

(5) The lateral guide devices are separately configured to have one of the guide surfaces (3a or 3b),
Alternatively, in the above item (3) or (4), the guide members are integrally formed so as to have respective guide surfaces (3a, 3b), and these lateral guide devices are linear edges or vertical rollers. Equipment for continuous welding in the longitudinal direction using the laser described.

(6) Any one of the above items (3) to (5), wherein the transfer device (2a, 2b) comprises a transfer roll (2a, 2b) having a tilting mechanism.
Equipment for continuous welding of strip-shaped steel sheets in the longitudinal direction by the laser described in the paragraph.

(7) Another lateral guide device (4a.4b) for guiding the side end of the strip-shaped steel sheet on the non-welded side is provided at a position facing the lateral guide device (3a, 3b). A facility for continuously welding a strip-shaped steel plate in the longitudinal direction by the laser according to any one of the above-mentioned items (3) to (6).

(8) The other lateral guide means (4a, 4)
(b) is a straight edge or vertical roller having a pressing mechanism, wherein the laser according to the above item (7) is continuously welded in the longitudinal direction by a laser.

(9) A path restraining device (5) for restraining each strip-shaped steel sheet is disposed downstream of the guide means (3a, 3b) with respect to the running direction of the strip-shaped steel sheet. A facility for continuously welding a strip-shaped steel sheet in a longitudinal direction by the laser according to any one of (8) to (8).

## EQU1 ##

As described above, according to the present invention, adjacent strip-shaped steel sheets are conveyed on different conveyance surfaces, and a predetermined distance between the end portions of the respective strip-shaped steel sheets on the side to be welded along the welding point extension line is conveyed on the conveyance surfaces. A gap L (L> 0) is set, and a predetermined gap L ′ (L ′) is set even on the same transport plane formed by converging each strip-shaped steel sheet.
It is possible to accurately and continuously weld a strip-shaped steel plate with a laser while maintaining ≦ L), and in particular, it is possible to provide a joining blank material for automobiles at low cost and with high productivity.

[0020]

BEST MODE FOR CARRYING OUT THE INVENTION Hereinafter, the present invention will be described in detail. In the method of the present invention, the adjacent strip-shaped steel sheets have an acute angle α.
, And at this time, the respective side ends on the side to be welded are conveyed at a constant interval L. The gap L formed between each side end is on the extension line of the welding point, and L> 0.
And That is, the side ends of the respective welded sides are in contact with the respective guide surfaces (each guide surface is set at an interval L) of the lateral guide device provided on the transfer surface, and are inclined at an acute angle α while being located next to each other. Are conveyed while maintaining a predetermined interval L 'in the same horizontal plane converged from the separate conveying surfaces. The interval L ′ is L ′> 0,
It is necessary to satisfy the condition of L ′ ≦ L. Then, the side ends on the side to be welded are welded at a predetermined interval L '.

The distance (L ') between the side ends on the side to be welded is 5
~ 50μ is desirable. If it is less than 5μ, the side edges on the side to be welded against each other will make it difficult to continuously transport. On the other hand, if it exceeds 50 μm, the welding time is greatly extended, productivity is impaired, and it is not practical.

The strip-shaped steel sheets are placed next to each other,
By transporting the side ends of each welded side in contact with their respective lateral guide surfaces set at a fixed interval,
Since the side ends on the side to be welded can be conveyed while being kept substantially in line at predetermined intervals as viewed in a plan view, the belt-like body maintained in the same plane at the welding execution position immediately after the convergence position of the conveying surface The butt precision (gap) required for laser welding can be ensured while preventing overlap between the parts or abutting between the side ends on the side to be welded.

In the equipment of the present invention, the transfer device such as a roll constitutes two transfer surfaces forming an acute angle α at an elevation angle as viewed in the reverse direction from the transfer direction, and each transfers a strip-shaped steel plate. The lateral guide device is installed at each transfer line position of the strip-shaped steel plates having different heights, and has a guide surface on an extension of the welding point. The lateral guide device is divided for each transport line and provided so as to have a transport surface. Further, it may be a single horizontal transport device having vertical and reverse transport surfaces in contact with each transport line.

The side end of each strip-shaped steel sheet is continuously conveyed while abutting on the guide surface. This transfer is not interrupted by processing operations in the welding equipment and there is no limit on the length of the welding length. In addition, the split-type split lateral guide device installed for each transport line is located at a different height from the pass line position of another strip-shaped steel plate, so it is necessary to install the guide device and attach accessories attached to it. Sufficient space can be secured.

Furthermore, since the side ends on the side to be welded are welded at an accurate distance (gap), the error rate during welding is reduced. It is preferable to use a roll for the transfer device, and by providing a tilting mechanism so that the center axis of the transfer roll can be tilted at an angle β as shown in FIG. The gap between them can be adjusted and is also useful as a lateral guide. The lateral guides are preferably designed as straight edges or vertical rollers.

Further, in order to accurately guide the side end on the side to be welded, it is desirable to provide another lateral guide device on the non-welded side, preferably at a position facing the lateral guide device. The other guide device may be a straight edge or a vertical roller having a pressing mechanism.

In order to make the transport of the strip steel sheet more accurate,
Downstream of the guide device, path restraining means can be arranged above and below the strip-shaped steel plate. The path restraining means may be, for example, a roll, which need not necessarily be driven,
A free rotation mechanism may be used. Particularly preferably, a pair of upper and lower path restraining devices is installed, and immediately after that, a laser welding machine is arranged. The smaller the distance between the path restraining device and the laser welding machine, the better. It would be further advantageous if the laser welder could be incorporated into a pair of upper and lower path restraining devices. The laser welding machine is not particularly limited, and for example, a CO ₂ , YAG laser can be used.

Also, the welding execution position is set at a fixed position because the side ends of the strip-shaped steel sheet on the side to be welded are kept at a constant interval on a plane perpendicular to the conveying direction of the strip-shaped steel sheet by the lateral guide device. It is not necessary to move the welding apparatus in the transport direction of the strip-shaped steel sheet and in the width direction of the strip-shaped steel sheet as the strip-shaped steel sheet is transported. Therefore, the welding device can have a very simple device configuration.

A monitoring device for checking the butting condition of the side ends on the side to be welded, that is, the gap distance and the welded seam can be arranged before and after the above-mentioned path restraining device. Further, the welding device according to the present invention is not necessarily limited to a laser welding machine as a welding machine, a welding machine capable of supplying a non-contact type heat source, for example, a plasma welding machine, a plasma-assisted laser welding machine, etc. Is also effective.

[0030]

Next, an embodiment will be described. FIG. 1 is an overall explanatory view showing an example of an apparatus for continuously welding the longitudinal direction of a strip-shaped steel sheet according to the present invention. Two strip-shaped steel plates 1a and 1b are mounted as coils on two uncoilers 11a and 11b, respectively. The strip-shaped steel plates 1a, 1b unwound from the uncoilers 11a, 11b are transported on transport surfaces a, b at different positions (heights) until immediately before the path restraining device 5. Through the outlet devices 12a and 12b, respectively, the entrance shear 1
3a and 13b. The defective portions at the leading end of the strip-shaped steel plate are cut by the entrance shears 13a and 13b, and the leveler 14 is cut.
After the shape is corrected by the free loops 15a, 1b
After passing through 5b, it converges immediately before the path restraining device 5 and passes through the path restraining device 5 to weld the side edges of the respective strip-shaped steel plates to be welded by the laser welding machine 6. afterwards,
The sheet is cut into sheets by the output side shear 21 and is stacked on the pallet 22. In addition, a strip-shaped steel plate connection device (not shown) may be provided on the output side of the input side shears 13a and 13b as needed.

FIGS. 2 and 3 are a side view and a plan view showing in detail the process of guiding the two strip-shaped steel plates and guiding them to the welding device main body. FIG. 4 shows the relative relationship between the side ends of the strip-shaped steel plate on the welded side. As shown in the figure, these two strip-shaped steel plates 1a, 1b are transported by transport rolls 2a, 2b constituting respective transport surfaces a, b, and a lateral guide device provided on the transport surface, for example, a linear edge 3 guide surfaces 3a,
While being guided by 3b, they approach each other at an acute angle α and converge immediately before the path restricting device 5. In the example of the figure, the lateral guide device 3 is separately installed for each transport surface,
Each of the transport surfaces 3a, 3b of the device is a strip-shaped steel plate 1a, 1b, respectively.
Contact with the welded end of the

The side ends of the strip-shaped steel plates 1a and 1b on the side to be welded are provided on the guide surfaces 3a and 3b of the lateral guide device, respectively, at the opposite ends of the strip-shaped steel plates 1a and 1b facing the guide surfaces. Another lateral guide 4a having a pressing mechanism,
4b. In this way, the welded ends are conveyed while being kept close to the distance L. As shown in FIG. 3B, the guide surfaces 3a and 3b are set so as to form an interval L, and therefore, the welded side ends of the strip-shaped steel sheet maintain the interval L (> 0). Because they are transported away, they do not overlap or hit each other.

The strip-shaped steel plates 1a and 1b are
The sheet is conveyed downstream by a and 2b, and converges immediately before the position of the path restricting device 5. At this convergence point, the two strip steel plates 1
a and 1b have the same height (same plane), and the side ends of the welded ends face each other at a predetermined distance L 'on this same plane as shown in FIG. The interval L ′ may satisfy the condition of L ′> 0 and may be equal to or smaller than the interval L,
If it is maintained in a range where the side ends do not contact each other, specifically in a range of 5 to 50 μm, the welding accuracy is not hindered.
It is preferable that the path restraint device 5 is installed as close as possible to the guide devices 3a, 3b, 4a, 4b.

Guide devices 3a, 3b, 4
The path restraint device 5 downstream of a and 4b comprises a pair of non-driven rolls. The roll 5 holds the conveyed strip-shaped steel plate and holds it under tension, so that the strips are arranged in the same posture at the laser welding execution position. A laser welding machine 6 is disposed immediately after the pair of rolls 5. Thus, the strip-shaped steel sheets supplied from the payoff reel can be continuously welded while maintaining the interval L '.

Further, the provision of the pass line restraining device prevents occurrence of displacement between the side ends on the side to be welded in the welding execution device. Lateral guide device 3a, 3b or 4a, 4
As b, a sliding stop in the form of a straight edge, a guide fence, a pressure roller, or the like can be employed. In the case of a guide fence or a sliding linear edge, the burrs at the side ends of the strip are smoothed by friction.

[0036]

As described above, according to the present invention, when the strip-shaped steel sheets are continuously welded in the longitudinal direction, a narrow predetermined gap is formed between the welded-side end portions so that the steel sheets can be welded to each other. Can provide a method and equipment for laser welding while ensuring the accuracy required for laser welding while preventing overlap between side edges and abutting, and particularly, a joining blank material for forming processing for automobiles Can be manufactured at low cost and with high productivity.

[Brief description of the drawings]

FIG. 1 is an overall explanatory view showing an embodiment of a continuous welding apparatus in the longitudinal direction of a strip-shaped steel sheet according to the present invention.

FIG. 2 is a side view for explaining a process of guiding adjacent strip-shaped steel plates and guiding them to a welding device.

3A is a plan view illustrating a process of guiding an adjacent strip-shaped steel sheet to a welding apparatus, FIG. 3B is a view illustrating a cross section taken along the line xy, and FIG. 3C is a cross-sectional view of another example. FIG.

FIG. 4 is an explanatory diagram showing a relative relationship between welded side ends of adjacent strip-shaped steel plates.

[Explanation of symbols]

 1a, 1b Strip-shaped steel plates 2a, 2b Transport device 3a First lateral guide device 4a Another first lateral guide device 5 Pass restraint device 6 Welding machine 11a, 11b Uncoiler 12a, 12b Exit device 13a, 13b Entry shear 14a, 14b Leveler 15a, 15b Free loop 21 Outlet shear 22 Pallet

──────────────────────────────────────────────────続 き Continued on the front page (51) Int.Cl. ⁶ Identification code FI B65H 23/182 B65H 23/182 Z

Claims (9)

[Claims] 1. A belt-like steel plate which is adjacent to each other is conveyed on separate conveying surfaces while being mutually inclined at an acute angle α as an elevation angle viewed in a direction opposite to the conveying direction, and a welding execution position on a conveying path. In the method of converging immediately before to form the same transport plane and continuously welding the welded end of each strip-shaped steel sheet by laser, The ends are conveyed at a constant distance L (L> 0), and the ends on the side to be welded are fixed at a constant distance L ′ in the same conveyance plane formed after the convergence position on the conveyance path.
(L ′> 0, L ′ ≦ L) and a method for continuously welding the strip-shaped steel plate in the longitudinal direction by a laser, wherein the side ends of the welded ends are laser-welded. 2. A belt-shaped laser beam according to claim 1, wherein the distance L ′ between the side edges of the strip-shaped steel plates to be welded in the same transport plane formed after the convergence position is 5 to 50 μm. A method of continuous welding in the longitudinal direction of a steel sheet. 3. The adjacent strip-shaped steel plates are conveyed in a state where they are mutually inclined at an acute angle α as an elevation angle viewed in a direction opposite to the conveyance direction, and converge immediately before the welding execution position on the conveyance path. Each transport device (2a, 2a) constituting a separate transport surface
b) In a facility for continuously welding a strip-shaped steel plate in the longitudinal direction by a laser having b), a transfer surface constituted by each of the transfer devices (2a, 2b) includes:
A guide surface (3) that comes into contact with the side end of each band-shaped steel plate on the welded side.
a, 3b) are provided, and the respective guide surfaces (3a, 3b) are arranged at a fixed interval L (L> 0), and are formed after the convergence position on the transport path. In the same transport plane, the side ends on the side to be welded are separated by a predetermined distance L '.
(L ′> 0, L ′ ≦ L), wherein the side ends of the welded ends are laser-welded to each other by a laser. 4. A belt-shaped laser beam according to claim 3, wherein the distance L ′ between the side ends of the strip-shaped steel plates to be welded in the same transport plane formed after the convergence position is 5 to 50 μm. Equipment for continuous welding in the longitudinal direction of steel sheets. 5. The lateral guide device includes a guide surface (3a, 3a).
5. The apparatus according to claim 3, wherein b) is constructed separately or integrally, and said lateral guide device is a straight edge or a vertical roller. 6. The strip-shaped steel sheet by a laser according to claim 3, wherein the transfer device (2a, 2b) comprises a transfer roll (2a, 2b) having a tilting mechanism. For continuous welding in the longitudinal direction. 7. A lateral guide device (4a.4b) is provided at a position facing the lateral guide device (3a, 3b) for guiding a side end of the strip-shaped steel sheet on the non-welded side. A facility for continuously welding a strip-shaped steel plate in the longitudinal direction by the laser according to any one of claims 3 to 6. 8. The lateral guide means (4a, 4b).
The equipment for continuously welding a strip-shaped steel plate in a longitudinal direction by a laser according to claim 7, wherein is a linear edge or a vertical roller having a pressing mechanism. 9. A path restraining device (5) for restraining each strip-shaped steel sheet is disposed downstream of the guide means (3a, 3b) with respect to the running direction of the strip-shaped steel sheet. A facility for continuously welding a strip steel plate in the longitudinal direction by the laser according to any one of the above.