JPH0215314B2 - - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a seam welding device for welding objects to be welded that are overlapped with each other.

Generally, the apparatus shown in FIG. 1 is used for lap-seam welding the leading end of a leading strip and the leading end of a trailing strip in, for example, a steel manufacturing line. That is, the cutting device 8 and the pressure roller mechanism 5 are mounted on the underframe 2, which is movable in a direction substantially perpendicular to the conveying direction of the strip 9, for example, in the Y direction.
and rotating electrodes 41 and 42 are arranged, and the underframe 2 is
Cut each end of the leading and trailing strips with the cutting device 8 while positioned at the end in the _Y1 direction,
After this, the end 9 of each strip is removed by a suitable mechanism.
1,92 are wrapped by a small amount as shown in FIG. 3a. In this state, a pair of pressure rollers 5
1 and 52, the underframe 2 is moved in the _Y2 direction to apply plastic deformation to the lap portion at the end of the strip, as shown in FIGS. 2a and 3b. After this step, as shown in FIG. 3c, the strips 9 are separated from each other by a small amount in the X direction, and then the frame 2 is moved in the _Y1 direction with the rotating electrodes 41 and 42 brought close to each other. Then, seam welding is performed in the state shown in FIG. 2b, and the already welded portion is plastically deformed by pressure rollers 51 and 52 so as to become flat. This results in a relatively thick strip being welded. By the way, when welding a thin strip, there is no need for the process of imparting plastic deformation before welding as shown in Figures 2a and 3b, and therefore the strip is welded as shown in Figure 3a. After the edges have been lapped a small amount, the underframe 2 is moved in the _Y2 direction in the state shown in FIG. That is, as shown in FIG. 2c, the underframe 2 moves in the _Y2 direction with the pressure rollers 51, 52 and the rotating electrodes 41, 42 separated from each other. Thereafter, as shown in FIG. 2b, the underframe 2 is moved in the _Y1 direction with the pressure rollers 51, 52 and rotating electrodes 41, 42 approaching each other, and the strips are welded. If the process of applying plastic deformation to the strip is not required before welding, the underframe should be moved from the end position in the _Y1 direction prior to the actual welding process.
A migration step is required to move the strip to the end position in the _Y direction, and the migration time becomes longer as the width of the strip increases. In addition, in this type of welding equipment, the underframe is heavy, so it is uneconomical to unnecessarily increase the driving force to move the underframe in the Y direction. The migration speed and the welding speed are configured to be approximately equal. By the way, as shown in Figure 1, when L ₁ , L ₂ and L ₃ are determined, the travel distance of the underframe in the Y ₂ direction; L is expressed as L≒L ₁ +L ₂ +L ₃ ...(1) It will be done. If the maximum width of the strip is 1400mm
For example, L ₁ = 1600mm, L ₂ = 200
mm, L ₃ =about 200 mm, and therefore, from equation (1), the above L is approximately 2000 mm.

Now suppose that the movement of the underframe and the welding speed; V is V=9
m/min, the underframe is at the above distance;
In order to migrate by L, a migration time of T=L/V≒13.3 seconds is required.

By the way, when welding the ends of the strip,
Transport of the strip to the welding equipment has been stopped. That is, during welding operations, it is necessary to stop new supply of strips to appropriate strip processing lines that are processes subsequent to the welding process.
However, in general, the strip is transported and processed at extremely high speeds, for example at 300 m/min, in post-processes after the welding process. A so-called looping device must be provided between the device and the downstream device for storing the long strip. By the way, for example, if the conveyance of the strip is to be stopped for 13.3 seconds as mentioned above, a looping device equivalent to L = 13.3 x 300 x 1/60 ≒ 67 m will be required, which will reduce the equipment cost of the strip processing line. The disadvantage was that the cost was soaring and the equipment area became large. Therefore, it has been desired to reduce the time required for welding the strips as much as possible. By the way, as shown in Fig. 1, with conventional welding equipment, the travel time of other underframes must be taken into account as the welding work time in addition to the actual welding time, so when welding thin strips, I was at a disadvantage.

On the other hand, without installing a cutting device on the underframe, the leading and trailing strips cut at a cutting position set at a position different from the welding position are brought to face the welding position, and the rear end of the leading strip and the trailing strip are A welding device has also been proposed in which the tip of the strip is positioned by an appropriate positioning mechanism and the welding device overlaps the strip by a small amount. In this case, in order to smoothly position the end of the strip, the rotating electrode and pressure roller mechanism disposed on the underframe are retracted out of the strip conveyance line as shown in FIG. Therefore, when welding thin strips,
Similar to the device shown in FIG. 1, the underframe had to be moved, which caused problems in terms of equipment cost and equipment area.

SUMMARY OF THE INVENTION An object of the present invention is to provide a seam welding device that eliminates the above-mentioned conventional drawbacks.

That is, it is an object of the present invention to provide a seam welding apparatus which can suitably weld strips ranging from thin to thick, and which can reduce the welding time in each case as much as possible.

Hereinafter, the present invention will be explained in detail with reference to illustrated embodiments. In FIG. 4, 1 is a frame, and 2 is an underframe which is movable in the Y direction while being restrained by a positioning means 3, and is moved in the Y direction by a driving means (not shown). Reference numerals 41 and 42 are a pair of rotating electrodes that can be moved toward and away from each other. For example, the upper rotating electrode 41 is supported to move in the Z direction by a suitable driving means.
51, 52 and 61, 62 are rotating electrodes 41, 5
For example, the pressure rollers 51 and 61 are driven by drive means 53 and 6, respectively, and are arranged on both sides in the welding direction, that is, in the Y direction.
3, for example connected to a hydraulically actuated cylinder Z
It is supported so that it can move freely in the direction. The above 51 to 53 and 61 to 63 constitute the first and second pressure roller mechanisms 5 and 6. Note that the cable 7 for feeding power to the rotating electrodes 41 and 42,
For example, the pressure roller support members 64 and 65 of the second pressure roller mechanism 6 are connected to the electrode support brackets 43 and 44, respectively.
3 and 44 in a non-contact state. 8 is a cutting device for cutting the end of the strip 9.

Next, the operation will be explained. Figures 4 and 5
In the figure, with the underframe 2 located at the end in the _Y1 direction, the leading strip 91 and the trailing strip 92 are connected to each other.
The end of the is cut by the cutting device 8, and after that,
A suitable mechanism, not shown, such as a clamp movable in the X direction, wraps each end of the strip 9 by a small amount, as shown in FIG. 3a. Thereafter, the first pressure roller mechanism 5, second pressure roller mechanism 6, and rotating electrodes 41, 42 are appropriately positioned according to the thickness of the strip 9, and seam welding is performed. The welding work from the first strip to the thick fourth strip will be explained in four sections.

First, in the case of a thin first strip, as shown in FIG. The pressure rollers 61 and 62 of the pressure roller mechanism 6 are in a pressurized state. In this state, the lap portion of the first strip 9 is welded while the underframe 2 moves in the _Y2 direction. This already welded portion is plastically deformed by the second pressure roller mechanism 6 and is formed relatively flat. After the pressure rollers 61, 62 pass the end of the first strip 9 in the _Y2 direction, the welding operation is completed. That is, a detector detects that the underframe 2 has moved to an appropriate position in the _Y2 direction, and the first strip 9 is conveyed in the _X1 direction or the _X2 direction based on the output signal of this detector. Note that after welding, the rotating electrodes 41, 42 and the pressure rollers 61, 62 are set in a separated state, and then the underframe 2 moves to the end position in the _Y1 direction, that is, to the retracted position. Of course, since the movement of the underframe 2 to the retracted position, that is, the movement, is carried out at the same time as the strip 9 is being conveyed, there is no risk of adversely affecting the operation rate of the steelmaking line as in the conventional case.

Next, in the case of a relatively thin second strip belonging to the second category, as shown in FIG. 5b,
Rotating electrodes 41 and 42 and pressure rollers 51 and 52 of the first and second pressure roller mechanisms 5 and 6, respectively.
Welding is performed by moving the underframe 2 in the _Y2 direction while maintaining the underpressure and 61 and 62 in a pressurized state. That is, the strip 9 is plastically deformed at the lap portion by pressure rollers 51 and 52, and the ends of the plastically deformed strip 9 are connected to the rotating electrodes 41,
Welded by 42. This already welded portion is plastically deformed by pressure rollers 61 and 62 and is formed relatively flat. After welding, the pressure rollers 51, 52 are separated and perform the same operation as shown in FIG. 5a.

Next, in the case of a relatively thick third strip belonging to the third division, the underframe 2 moves in the _Y2 direction and performs the first processing as shown in FIGS. 3b and 5c. A pressure roller mechanism 5 applies plastic deformation to the lap portion at the end of the strip. After this step, the third
As shown in FIG. 5c, the strips 9 are separated from each other by a small amount in the X direction, and then as shown in FIG. Welding is performed by moving the underframe 2 in the _Y1 direction while maintaining the pressurized state.

Furthermore, in the case of a thick fourth strip belonging to the fourth category, the underframe 2 is
While moving in the _Y direction, the first pressure roller mechanism 5
This applies plastic deformation to the lap portion at the end of the strip. In this case, if the first and second pressure roller mechanisms 5 and 6 are made to cooperate, the plastic deformation becomes somewhat larger, which is more effective. After this process,
As shown in FIG. 3c, the strips 9 are spaced apart from each other by a small amount in the X direction, and then the rotating electrodes 41, 42 and the
The pressure rollers 5 of the pressure roller mechanisms 5 and 6 of
1, 52 and 61, 62 are maintained in a pressurized state, the underframe 2 is moved in the _Y1 direction, and welding is performed.
That is, the lap portions at the ends of the strip are further plastically deformed by pressure rollers 61 and 62, and the ends of the strip 9 that have been plastically deformed again are welded by rotating electrodes 41 and 42. This already welded portion is plastically deformed by pressure rollers 51 and 52 and is formed relatively flat.

As shown in FIG. 4, for example, in the second pressure roller mechanism 6, the axis of the support member 64 that supports the pressure roller 61 and the axis of the cylinder rod of the driving means 63, for example, a fluid pressure operated cylinder, are aligned. If they are connected by hinge connection so that they do not coincide, the distance between the rotating electrode 41 and the pressure roller 61 can be made as close as possible. Of course, if the driving means 53 of the first pressure roller mechanism 5 is similarly provided, the distance between the pressure roller 51 and the rotating electrode 41 can be made closer.

As described above, when welding the lap portions of relatively thin strips corresponding to the first and second sections, the underframe moves in the _Y2 direction as shown in Figures 5a and 5b. Welding
After the underframe reaches the end in the _Y2 direction, the strip can be transported in the X direction regardless of the movement of the underframe in the _Y1 direction. In other words, the movement of the underframe in the _Y1 direction is carried out at the same time as the strip is conveyed, so
There is no need to consider the travel time of the underframe, and therefore the welding time can be about half that of conventional equipment, so the looping equipment installed between the welding process and the subsequent process can be of small capacity.

In addition, as shown in Figures 5c and 5e, the lap portions of the strip ends that have been plastically deformed are separated from each other and then plastically deformed again, and after this, the seam welding and the welded parts are welded. Because plastic deformation is applied, it is possible to weld thicker strips than can be seam welded with conventional equipment.

As described above, according to the present invention, strips ranging from thin to thick can be welded with high performance using one welding device, and particularly when welding relatively thin strips, the welding time required to stop the strip can be reduced. Since the amount of rubbing is only about half that of the conventional method, the capacity of the ruving device installed between the welding process and the post-process can be reduced, and the equipment cost of the strip processing line can be lowered and the equipment area can be reduced. can.

[Brief explanation of drawings]

FIG. 1 is a front view of the conventional device, FIGS. 2 a to c are explanatory diagrams of the operation of FIG. 5th front view showing the embodiment of
Figures a to e are explanatory views of the operation of Figure 4. 2... Underframe, 41, 42... Rotating electrode, 5, 6
...first and second pressure roller mechanisms, 9, 9
1,92...Strip.

Claims (1)

[Claims] 1. A pressure roller mechanism having upper and lower rotating electrodes that can be freely approached and separated by an elevating device, and upper and lower pressure rollers that can be freely approached and separated from each other by an elevating device and that clamp and plastically deform the workpiece to be welded, A seam welding device comprising front and rear pressure roller mechanisms disposed on the front and rear sides in the welding direction across a rotating electrode.