JPS6355396B2 - - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a steel strip clamping device for butt welding, and is particularly suitable for butt laser welding in which butt precision is strictly required. We propose a steel strip clamping device suitable for clamping steel strips.

Generally, in an annealing process line in the steel industry, leading and trailing steel strips are connected at the input side of the line and sent out to a predetermined treatment process. General-purpose automatic welding machines used for this purpose include seam welding machines, flat patch welding machines, and TIG/MIG welding machines, but in recent years laser welding has attracted attention because of its low heat input and high-speed welding characteristics. Ta.

However, in laser welding machines, the focal diameter of the condensed laser beam is very small, so when butt welding steel plates together, a fairly high precision welding line is required.

However, in a general steel process, for example, when butt welding leading and trailing steel strips, the leading and trailing steel strips are cut with a double cut shear or the like,
These cut surfaces are butted together and welded. That is, one side of the steel strip cut by a double cut shear as illustrated in FIG. 3 is moved to the other side to form a welded joint surface, but if cut according to the conventional method, the steel strip shown in FIG. 8A, As shown in 1 of B, the cutting line where the mating surfaces are in the sheet width direction is not a clean straight line, and the gap G varies in size (Gmax, Gmin.) between the operating side and the driving side of the line. . This gap G
This is a plate thickness of 1.0 to 3.0 mm, and although there are differences depending on various cutting conditions, it is generally about 0.1 mm, and especially in shears equipped with blades with rake angles, the end of the cut tends to be narrower.

For this reason, if a weld line is formed by simply moving either side of the material to be welded (steel strip) in parallel, a gap difference will remain as shown in Figure 8-2, making it unsuitable for laser welding. This makes welding virtually impossible, especially if filler wire is not used.

In view of such circumstances, an object of the present invention is to provide a clamping device that allows the end faces of steel strips to be butted to come into contact with each other as closely as possible over the entire width of the steel strip, making it well suited for laser welding. In order to achieve this purpose, the clamp device is constructed as described in the claims at the beginning of this specification. That is, the present invention vertically sandwiches the region near the rear end of the preceding steel strip and the region near the tip of the following steel strip,
In a device equipped with a pair of upper and lower clamps that bring the end faces of each steel strip into close contact to suit laser butt welding, at least one of the upper and lower pairs of clamps is reciprocated along the steel strip conveyance line. The present invention is characterized in that it is disposed on a support member that is tiltable with respect to the steel strip conveyance line within the horizontal plane of its movement limit.

In short, this invention supports at least one of each pair of upper and lower clamps on a support member (hereinafter referred to as a sliding saddle) that can move forward and backward in a steel strip conveyance line, and when this is moved for butting, the At the limit of movement, it is in an unrestricted state, and the other side is tilted in a horizontal plane using one side as a fulcrum, so that a tight connection can be achieved. Here, a stopper is provided to restrict the forward movement of the clamp (hereinafter simply referred to as the movable clamp) supported on a sliding saddle that can move forward and backward, and this stopper allows the movable clamp to be set at different positions. It is preferable to configure the gap G after alignment so that it can be adjusted as appropriate. The details of the configuration of the present invention will be explained below based on the drawings.

First, the specific configuration of the present invention shown in the illustrated example will be summarized and explained: The movable clamp is supported on the base plate of the machine via, for example, a portal-shaped sliding saddle. The sliding saddle has a pair of stopper mechanisms provided on the base plate at two locations on the line operation side and the driving side to restrict the movement of the sliding saddle, and engages with the lower surface of the saddle to move it in the line direction. A guide wall that is connected to a pair of cylinders provided for reciprocating motion, and that has notches on both sides of the operation side and drive side walls along the line of the base plate, the ends of which are butt facing inward. A guide wheel attached to the portal leg of the sliding saddle is brought into rolling contact with the guide wall of the guide device, so that the saddle is in a horizontal plane at the front end of its movement. Allow it to tilt.

The present invention will be explained below using an example of a clamp device used when butt welding the tail end of a leading steel strip and the tip of a trailing steel strip using a laser welding machine.

In FIGS. 1 to 3, 1 is a laser oscillator placed offline, 2 is a shearing machine placed offline, and 3a and 3b are clamp devices. Oscillator 1
The laser beam emitted from the steel strip is focused on a laser torch 4 that can move in the width direction of the steel strip, and irradiates the joint surface of the steel strip to perform welding.

The clamping device consists of an exit clamp 3b that clamps the tail end of the preceding steel strip, and an entry clamp 3a that clamps the tip of the trailing steel strip.In the following explanation, the entry clamp 3a is the exit clamp. 3b
This will be explained using an example of moving towards .

Each of the clamp devices is supported on a machine stand 11, and the movable entry side clamp 3a is supported via a sliding saddle 17 on a base plate 11a on the machine stand. This sliding saddle 17 reciprocates along the line direction toward the outlet side clamp 3b via cylinders 16, 16', and a lower fixed clamp 15 is placed on this sliding saddle 17.
An entry side clamp 3a is placed thereon, and includes a cylinder 14a for lifting and lowering supported by an upper frame 13a. Note that the illustrated symbols 12b and 13
b, 14b, and 15b show the fixed-side output clamps 3b that are arranged opposite to each other.

The method of clamping is to use a pair of upper and lower clamps 12.
The upper clamp 12a is clamped onto the steel strip S passing between a and 15a by lowering the lifting cylinder 14a.

Next, the operating procedure of the mechanism, ie, the sliding saddle, for moving the steel strip S clamped as described above toward the other outlet side clamping device 3b will be described. The movement is performed via cylinders 16 and 16' installed separately on the line operation side and the drive side on the base plate 11a, and the free ends of the rods from which the cylinders 16 and 16' retract are connected to the base plate 11a. is secured to the lower surface of a sliding saddle 17 arranged to straddle the
By operating these cylinders 16, 16', the sliding saddle 17 and the entry clamp itself placed thereon are moved forward and backward to obtain a tight butt surface of the steel strip that will become the weld line. .

Next, a mechanism for regulating the movement width (advance limit of movement) of the entry side clamp 3a will be described with reference to FIGS. 4 and 5. The sliding saddle 17 has an arm 17a provided with a hook on the rear thereof, and the forward movement of the saddle 17 is regulated by the following stopper mechanism disposed on the base plate 11a. This stopper mechanism consists of stoppers 18 and 18' and a screw shaft 27 that directly meshes with the stoppers 18 and 18'.
and 27', and a motor 32 connected via gears 28, 28', 29, 30 and a shaft 31 provided on the extension thereof, and this motor 32 is connected to the screw shafts 27, 27'. Pressure detectors 25, 25' such as load cells are in contact with the hook of the saddle arm 17a attached to the rear end.
It is driven by the detected pressure of
Stoppers 18, each located on the drive side,
The configuration is such that different positions can be set for each 18'. Therefore, this stopper 18,1
Sliding saddle 17 whose forward width is regulated by 8'
That is, the entry side clamp 3a will be tilted within the horizontal plane of its movement limit (see FIG. 5B), as will be described later.

Next, the sliding saddle 17: that is, the entry side clamp 3a
The mechanism of the movement limit in the horizontal plane will be explained based on FIGS. 5 to 7. The saddle 17 is mounted on the base plate 11a by the cylinders 16, 16'.
In order to make the movement smooth, guide walls 34, 34' are provided on both sides of the base plate 11a, and the portal legs of the saddle 17 are attached to the guide walls 34, 34'. Part 17
A plurality of guide wheels 35 attached to b are brought into rolling contact with each other. Therefore, the saddle 17 is disposed so as to straddle the base plate 11a; that is, the clamp 3a supported by the saddle 17 is arranged so as to straddle the base plate 11a;
4, 34', reciprocate in the line direction via a guide wheel 35.

By the way, the arm 17a of the saddle 17 is
The saddle 17 moves forward in parallel until it comes into contact with one of the stoppers 18, 18', but after that, until it comes into contact with the remaining stopper, the saddle 17 is operated to further push the side that has not made contact with it. As shown in FIG. 5B, it tilts at an angle θ with respect to the steel strip conveyance line, resulting in a substantially rotating movement. In order to facilitate such movement of the saddle 17, the guide walls 34, 3
A notch 34a is provided at the end of the abutting side of the guide wheel 35 so as to face inward toward each other.
When the saddle 17 reaches this notch 34a, the saddle 17
is tilted, and any uneven gap occurring across the width of the strip, as shown in FIG. 8, is corrected, thus creating a closely abutted weld line.

In addition, in the above explanation, the stopper 18,1
I gave an example where the motor that drives 8' is common, but
This may be done separately for the operating side and the driving side. Further, although the movable clamp is limited to the entry side, it may be provided on the other side (output side) or both.

Next, the operation of the device of the present invention will be explained based on FIG.

●First, the example shown in Fig. 8B (example without filler wire): When the leading steel strip and the trailing steel strip are fed to a predetermined position and stopped, the cylinders 14a and 14b of the inlet and outlet clamps 3a and 3b are activated. and clamp the leading and trailing steel strips. Next, the shearing machine 2 is advanced into the line to cut the leading and trailing steel strip ends. After cutting, the shearing machine 2 moves back to a predetermined position. Next, actuate the cylinders 16 and 16', and
Move a forward. At this time, stoppers 18 and 1
8' is set slightly wider than the distance between the end faces of the steel strip cut by the shear (referred to as the cutting interval). In this way, the entry side clamp 3a initially moves in a direction parallel to the line, and the entry side clamp 3a comes to the forward end portion of the butt, and the guide wheel on the side closer to the exit side clamp 3b moves to the notch 34a of the guide wall 34. engage with. In this state, the entry side clamp 3a is not constrained in the horizontal plane and can move further if the cylinders 16, 16' are actuated.

That is, as shown at 2 and 3 in Fig. 8, when one end of the steel strip in the width direction comes into contact, the saddle 17 tilts together with the entry clamp 3a in a direction that makes the gap g at the other end zero, and the other end comes into contact. Stop at the point. As a result, the gap at the time of butt can be made smaller than when the steel strip held between the entry side clamps 3a is immediately advanced along the line.

At this time, the trailing steel strip becomes oblique to the line due to the tilting of the entry side clamp, but the value is
It is around 0.1/1000mm, so there is no problem.

●Example in Fig. 8A (example when using filler wire); In this example, the position of the stoppers 18, 18' is smaller than the cutting interval, and the saddle, that is, the entry side clamp 3a, is in the direction parallel to the line. First, the guide wheel 35 moves forward, and the guide wheel 35 near the exit clamp side 3b reaches the notch 34a of the guide wall 34, and the entrance clamp 3a becomes unrestrained in the horizontal plane. When the cylinders 16, 16' are further actuated, the arm 17a of the sliding saddle 17 supporting the entry clamp comes into contact with the stoppers 18, 18', resulting in the state shown in FIG. It will stop with a slight gap. Next, when the butt is completed, a filler wire is supplied and the laser torch 4 is moved in the width direction of the steel strip to perform welding to fill the gap g'.

As explained above, according to the clamping device of the present invention, the abutting portions that form the weld line in laser welding or the like can be brought into close contact, and highly accurate welding can be achieved.

In the above embodiment, a guide wheel is provided on the sliding saddle and a notch is provided on the base plate on the fixed side. You may also do so. Furthermore, the sliding side and the fixed side may be reversed, and there are four modes including the above embodiment.

[Brief explanation of the drawing]

Figure 1 is a plan view of a laser welding machine for steel strips;
Figures 3 and 3 are a front view (Figure 2) and a side view (Figure 3) of the laser welding machine installed in the line.
Figure 4 is a front view of the movable clamp device.
Figure 5A is a plan view showing the stopper mechanism on the base plate, Figure B is a schematic diagram showing how the saddle is driven, and Figure 6 is a guide wall and guide wheel showing the saddle movement position. An explanatory diagram showing the relationship between
FIG. 7 is an explanatory view showing the relationship between the saddle and the cylinder, and FIG. 8 is an explanatory view of the step of butting steel strips in the implementation of the present invention with and without use of filler wire. 1... Laser oscillator, 2... Shearing machine, 3a, 3
b... Clamp device, 4... Laser torch, 11
... Machine base, 11a ... Base plate, 12a,
12b... Upper clamp, 13a, 13b... Upper frame, 14a, 14b... Lifting cylinder,
15a, 15b... Lower clamp, 17... Sliding saddle (support member), 17a... Arm of sliding saddle, 18, 18'... Stopper, 25, 2
5'...Pressure detector, 26...Guide, 27,2
7'... Screw shaft, 31... Axis, 32... Motor, 34... Guide wall, 34a... Guide wall notch, 35... Guide wheel.

Claims (1)

[Claims] 1. A region near the rear end of the preceding steel strip and a region near the tip of the following steel strip are sandwiched above and below, respectively,
In a device equipped with a pair of upper and lower clamps that bring the end faces of each steel strip into close contact to suit laser butt welding, at least one of each pair of upper and lower clamps is moved back and forth along the conveyance line of the steel strip. 1. A steel strip clamping device for laser butt welding, characterized in that the device is disposed on a support member that is tiltable with respect to a steel strip conveyance line within the horizontal plane of its movement limit.