JPS5884685A - Seam welding machine workpiece guidance device - Google Patents

Abstract

PURPOSE:To improve operability at the time of working by providing a profile cam, oscillatory rollers and thereby enabling to guide an object to be welded having complicated shape at a uniform speed regardless of the condition of the corner part. CONSTITUTION:The device consists of a profile cam 13 that has the same shape with the weld line of an object 10 to be welded, an inside roller that is in pressure contact with the inner peripheral face of the cam 13, plural small diameter rollers 19 arranged at a distance on the left and right of the inside roller to make pressure contact with the inner peripheral face of the cam 13, a large diameter roller 20 that can move in the direction perpendicular to the cam 13 provided between the roller group 19 and in pressure contact with the outer peripheral face of the cam 13, and an air motor 24 that drives the roller 20. The cam 13 is fixed to the same shaft with a stand on which the object 10 to be welded is placed. The inside roller is attached to the tip of an oscillatory arm 16 connected to a cylinder allowing free rotation. By this device, the object 10 to be welded can be guided at a uniform speed.

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a workpiece guiding device for a seam welding machine that is capable of guiding a complicated workpiece along its welding line at a constant speed.

Recently, the method of seam welding the outer periphery of objects to be welded, such as automobile gasoline tanks, as shown in Figures 1a and b and Figure 2, using an induction device has become increasingly popular for reasons such as productivity, quality, and human resources. In response to demand, several types of mechanisms are in practical use.

However, conventional mechanisms have the disadvantage that they are complicated and difficult to operate.

Here, when seam welding objects to be welded having shapes as shown in FIGS. 1A and 2B and FIG. 2, the corner portions of the objects become a problem. In other words, especially at the corners, due to the large inertia of the guiding device, the rotational torque applied from the electrode disk to the workpiece is insufficient, and the guiding device cannot rotate sufficiently.
The orbit of the electrode disk may deviate from the specified welding position, the electrode disk may fall off the flange of the workpiece, making welding impossible, or the rotational speed, that is, the welding speed, may decrease due to insufficient rotational force. There may be deviations from appropriate construction conditions.

Under such circumstances, two to three methods have been proposed so far in order to guide the corners of the workpiece without causing the above-mentioned problems.

For example, there is a method shown in FIG. The method shown in FIG. 3 is such that when the upper electrode disc 2 approaches the corner of the workpiece 1, a link-shaped arm 3 is pushed by a cylinder 4 to increase the rotational force of the guiding device. .

On the other hand, in addition to this method, a method has been proposed in which a fluid motor is attached to the center shaft of the copying cam and the fluid motor is driven at a corner portion to easily rotate the copying cam.

By the way, in the case of a device that presses the arm 3 with a cylinder 4 as shown in FIG. Although it is easy to apply, it is possible to weld the workpiece 1 with a complicated shape as shown in Fig. 2.
has the disadvantage of being difficult to apply. That is, when the workpiece 1 to be welded has a complicated shape, the center distance of each corner (R1, R2, R3, R4, R5 in Fig. 2), radius of curvature (rl, r2 in Fig. 2) .r3.r4.r5
), formation angle (in Fig. 2, θ1.θ2.θ3.θ4.θ
5) It is necessary to select cylinders 4 with strokes corresponding to the above, install the cylinders 4 at appropriate positions, and control each cylinder accurately. Therefore, not only the device becomes complicated and expensive, but also the operation becomes extremely complicated.

In the case of a device equipped with a fluid motor on the center shaft of the copying cam, even when applying rotational torque from the center shaft, the distance between centers, radius of curvature, and forming angle of each corner of the workpiece 1 are different. Nevertheless, a constant angular velocity will be applied, and as shown in Figure 4, if the distance between the centers doubles, the speed will also double, and if this condition is used until the trench is used, quality problems will occur. There is a fear. In addition, in FIG. 4, the movement amount of point P and 22 points is explained with the 0 point as the center of rotation. In the figure, W is the angular velocity of the motor. If you try to give the rotation speed according to the corner part, many 1
It is necessary to prepare a pressure reducing valve and apply fluid pressure to the fluid motor using a solenoid valve at each corner, and this method also results in an expensive device and poor operability.

It is an object of the present invention to solve these conventional drawbacks and to enable accurate beam welding with a simple structure.The following describes the workpiece guiding device for a seam welding machine according to the present invention. This will be explained using the drawings of FIGS. 5 to 7.

In the figure, 10 is the object to be welded, 11 is the upper electrode disk, 1
1' is a lower electrode disk, 12 is a link-like arm, 13 is a copying cam, 14 is a support for the workpiece 10, 15 is a clamp cylinder, 16 is an arm, 17 is a bracket, 18 is an inner roller, 19 2Q is an outer small diameter roller, 2Q is an outer large diameter roller, 21 is a spring, 22 is a guide, 23 is a guide bar, and 24 is an air motor.

Here, the workpiece 10 is placed on the stand 14 in phase with a copying cam 13 machined to have the same shape as the weld line of the workpiece 1 . Further, since the copying cam 13 and the support base are fixed to the same shaft, the workpiece 1o and the copying cam 13 move in the same manner. Further, on the inner peripheral side of the copying cam 13, an inner roller 18 is rotatably attached to the tip of the arm 16 connected to the rond of the clamp cylinder 16.
is arranged so as to be in pressure contact with the inner circumferential surface of the copying cam 13. Since the arm 16 is pivotally supported by a bracket 17, it can swing, and the inner roller 18 is attached to the workpiece 10.
It is now possible to follow changes in the shape of the Copy cam 1
A plurality of (four in the figure) small-diameter rollers 1 are arranged on the outer circumferential side of the inner row 218 with a slight interval between them so as to press against the outer circumferential surface of the copying cam 13 at the left and right positions of the inner row 218.
9 is rotatably arranged. At an intermediate position between the plurality of groups of small diameter rollers 19, there is a large diameter roller 20 that faces the inner roller 18 via the copying cam 13 on the same line as the central axis of the upper electrode disk 11 and the lower electrode disk 11'. This large diameter roller 2o is brought into pressure contact with the outer peripheral surface of the copying cam 13 by a spring 21, and the guide 2o
2 and a guide bar 23, it is movable in a direction perpendicular to the outer peripheral surface of the copying cam 13. In addition, large-diameter rollers
The controller 20 is keyed to the shaft of the air motor 24.
It is rotated by an air motor 24.

Next, the function of the guiding device configured as described above will be explained. The pressure applied by the clamp cylinder 15 causes the inner roller 18 and the outer small-diameter roller 19 to clamp and guide the copying cam 13. At the corner of the workpiece 10, the rotational force of the air motor 24 is applied to the outer large diameter roller 1.
8 and the outer small-diameter roller 19 sandwich and guide the copying cam 13, and at the corner of the workpiece 10, the rotational force of the air motor 24 is transmitted to the copying cam 13 via the outer large-diameter roller 20. , supplements the rotational force of the guidance device at the corner and allows for smooth movement.

That is, when the guiding device of the present invention is used, it is possible to guide the welded object 1° at a relatively uniform speed regardless of the condition of the corner part even for the welded object 10 with a complicated shape, and the seam This not only stabilizes the quality of the welded product, but also improves operability.

As described below, according to the workpiece guiding device of the 7-mm welding machine of the present invention, even workpieces with a simple structure and complex shape can be welded relatively uniformly, regardless of the condition of the corner part. This allows the workpiece to be welded to be guided at a fast speed, making it possible to stabilize the quality of seam-welded products and improving operability during work.

[Brief explanation of drawings]

Figures 1a and b are top and front views showing an example of the shape of the workpiece, Figure 2 is a top view showing another example of the shape of the workpiece, and Figure 3 is a conventional workpiece guidance device. FIG. 4 is an explanatory diagram showing changes in the rotational speed of the course of the workpiece in another conventional workpiece guidance device, and FIG. 5 is an embodiment of the present invention. FIGS. 6 and 7 are plan views showing the overall structure of a workpiece guiding device for a seam welding machine according to the present invention, respectively. 10... Work to be welded, 11... Upper electrode disc, 11'... Lower electrode disc, 12.16.
... Arm, 13 ... Copying cam, 14.
...ψ...Brace is stand, 15...Clamp cylinder, 18...Inner roller, 19...-Small diameter roller, 20...Large diameter roller, 24 temples...
・Air motor. Name of agent: Patent attorney Toshio Nakao (1st person)
Figure 2 Figure 3 Figure 5 Figure 6 f'7 24 2f

Claims (1)

[Claims] The receiver on which the workpiece is placed is fixed to the same axis as the table, and is rotatably attached to the tip of a swingable arm connected to a copying cam that has the same shape as the weld line of the workpiece and a cylinder. , and an inner roller that presses against the inner circumferential surface of the copying cam, and a plurality of small diameter rollers that are spaced apart from each other so as to press against the outer circumferential surface of the copying cam at the left and right positions of the inner roller. and a large-diameter roller disposed at an intermediate position between the plurality of small-diameter roller groups so as to be movable in a direction perpendicular to the releasing cam and to be in pressure contact with the outer peripheral surface of the copying cam, and this large-diameter roller. A welding object guiding device for a seam welding machine consisting of an air motor that drives the seam welding machine.