JPH06226448A - Welding wire forming device - Google Patents

Abstract

PURPOSE:To stabilize the feed at welding process by forming the wire feeding out through a push method to rather a helical or wave form, etc., in the circumferential direction. CONSTITUTION:By rotating a toothed pully 7 through a toothed belt and motor, a welding wire is feeded out in the arrow mark direction with catching by feed out rollers 12, 13, a forming die 8, which is arranged with off centered to the toothed pully 7, makes eccentric motion, forming the welding wire into a hilical form. At this time, a pitch of the helicoid is decided by a feed out speed of the welding wire 15 and rotating speed of the toothed pully, the forming die 8 is tilted to naturally matched to a lead angle of the helicoid by a spherical bearing 9, forming the welding wire 15. The helical winding diameter is 5 times of the welding wire diameter and pitch is >=2 times of winding diameter. By this wire forming, the insulation length is increased and toughness is improved, the feed resistance at spring liner in wire feed process is dispersed, absorbing and stabilizing the feed resistance difference generated by the attitude change of robot wrist.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a welding wire feeding device for arc welding with a consumable wire such as CO ₂ welding or mag welding, and more particularly to a wire feeding device suitable for continuous welding by a robot.

[0002]

2. Description of the Related Art In order to send out a welding wire in MAG welding by a robot, generally, a welding torch attached to a wrist of a robot and a feeding mechanism attached to an arm are arranged at intervals of 1 meter or more because of workability. A wire position guide and a wire position guide are provided at the wire exit part of the tip of the welding torch by a push method in which the wire is connected by a spring liner in the form of a close-coiled spring that is wound about twice the wire diameter and the wire is fed into this spring liner. In order to supply a welding current to the contact tip, a contact tip having a hole having a wire diameter is arranged.

[0003]

[Problems to be Solved by the Invention] The wire sent out by the push method is always sent out in a state in which a buckling force is applied, and in order to keep it straight in the sent out state, It is desirable that the spring liner that serves as a guide so as to have a low resistance is straight and short, and has an inner diameter with a small clearance with the wire. However, in robot welding, the wire is bent and twisted due to the posture change of the robot wrist during the welding process.

In such a state, the length and diameter of the spring liner inevitably become large in order to reduce the feeding resistance and the difference therebetween, but the wire to be fed is bent irregularly in the spring liner. Since the wire is sent out while rolling, the wire sent out from the contact tip at the tip of the welding torch bends in an irregular direction and rolls, resulting in poor aiming accuracy.

Further, the portion where the wire is fed out linearly depending on the welding posture is more instable and uncertain in the contact state with the contact tip than when the wire is bent and fed out. Furthermore, the wire passage of the contact tip is almost consumed due to the diameter of the wire, which changes the target point of the wire, the feeding point, and the contact pressure, causing the welding bead to shift or become uneven, increasing spatter generation and increasing the contact tip and wire. This has been a cause of adverse effects such as welding with.

[0006]

SUMMARY OF THE INVENTION According to the present invention, a welding wire is formed in a spiral or corrugated isosceles direction to such an extent that the wire sent out by the push method does not cause great elasticity in the longitudinal direction. By increasing the absolute length and strengthening the wire toughness, the contact surface pressure that the wire is pressed against the inner wall of the spring liner is diffused during the feeding process, and the feeding resistance difference due to the change in the posture of the robot wrist during the welding process is absorbed. As a result, irregular bending and rolling of the wire fed from the tip of the contact tip are prevented, and the relative diameter of the wire is increased to stabilize the contact state with the contact tip and reduce wear.

Specifically, in the process of feeding a wire for arc welding with a consumable wire, the wire has a diameter of 5
It is formed into a spiral shape with a diameter within 2 times and a pitch of 2 times or more of the diameter. Alternatively, the wire is bent in the circumferential direction of three or more directions in a wavy shape with an amplitude within 5 times the wire diameter and at a pitch of at least 2 times the amplitude. Alternatively, the wire is bent in a wavy pattern at a constant pitch, and is further spirally bent at an amplitude within 5 times the wire diameter and at a pitch not less than 2 times the amplitude.

[0008]

First Embodiment A toothed pulley 7 is integrally attached to shaft plates 5 and 6 and is held by holding plates 1 and 2 via ball bearings 3 and 4. A hole-shaped molding die 8 is arranged at an eccentric center of the toothed pulley 7 via a spherical bearing 9. The holding plate 2 is provided with a guide 16 for guiding the wire before forming, and the holding plate 1 is provided with a spring liner 10 for guiding the wire after forming.

In the above state, while rotating the toothed pulley 7 through the toothed belt and the motor (not shown),
When the welding wire 15 is sandwiched by the feeding rollers 12 and 13 and is fed in the direction of the arrow 14, the forming die 8 eccentrically arranged on the toothed pulley 7 moves eccentrically to form the welding wire 15 in a spiral shape. At this time, the spiral pitch is determined by the feeding speed of the welding wire 15 and the rotational speed of the toothed pulley, and the spherical bearing 9 causes the forming die 8 to naturally tilt at an angle that matches the lead angle of the spiral.
To mold.

The rate at which the welding wire 15 is formed in a spiral shape is such that if the diameter of the spiral winding is large relative to the diameter of the wire, the elasticity in the longitudinal direction, such as a coil spring, increases.
Irregular vibrations are generated in the welding wire 15 to be fed, and the wire feeding becomes unstable and becomes an obstacle to welding. Therefore, the spiral winding diameter is practically within 5 times the welding wire diameter and the pitch is more than 2 times the winding diameter. And have to. (In the experiment, the wire diameter was 1
Mm roll diameter 2 mm pitch 10 mm)

[00011] When a welding wire formed into a spiral shape and having an increased absolute length and toughness is pushed into the spring liner and pushed out by a buckling force in the process of being sent out, the welding wire is spirally wound. Since the contact pressure is distributed along the reed lead, the wire feeding resistance is small and the resistance difference in the spring liner due to the position change of the welding torch during the welding process is also small.

Therefore, the axis of the wire fed out from the tip of the contact tip is stable and is close to a straight line, and the aiming accuracy of the welding line is good. Moreover, since the wire is helicoidal as compared with the conventional straight wire, not only the wire diameter of the contact tip is large and the contact area is increased, but also the wire is formed by the elasticity of the spirally formed wire in the circumferential direction. The contact power supply is good and the consumption is low and welding is stable.

[00013]

[Second Embodiment] Wire feeding rollers 22 and 23 and side rollers 28 (opposite side rollers are not shown) for sandwiching the wire at right angles thereto are arranged. The surface of each roller is formed in a gear shape as shown in FIG. 3, and the welding wire is bent in a wavy shape and is bitten therein.

When the rollers 22 and 23 are driven in the directions of the arrows 26 and 27 in the above-mentioned state, the welding wire 25 is fed in the direction of the arrow 24 while the gears formed on the surface of the roller cause the welding wire to move vertically with respect to the axis. It is bent in a wavy shape in the horizontal and horizontal directions.

[0001] When a welding wire, which is vertically and horizontally bent in a wavy shape, is pushed against the inner wall of the spring liner by a buckling force in the process of being pushed out into the spring liner and sent out, the contact with the inner wall causes a plurality of bending heads. Since it is dispersed in the wire line, the wire feed-out resistance is small, and the resistance difference in the spring liner due to the position change of the welding torch during the welding process is also small.

Therefore, the axis of the wire fed out from the tip of the contact tip is stable and is close to a straight line, and the aiming accuracy of the welding line is good. Further, since the wire is bent vertically and horizontally in a wavy shape as compared to the conventional straight wire, not only the wire passage diameter of the contact tip is large, but the contact area is increased, and the wire is bent and added in the circumferential direction. Due to its elasticity, the power supply to the wire is good and the welding is stable.

[00017]

[Third Embodiment] The feed rollers 32 and 33 have gear-like surfaces as in FIG. 3, and a welding wire 35 is bent in a wavy shape and is bitten therein. The wire 35 bent in a wave shape by the sending rollers 32 and 33 is 180
It is twisted and is sandwiched between the twist rollers 38 and 39 having flat surfaces.

In the above state, the feeding roller 3
By driving Nos. 2 and 33 in the directions of arrows 36 and 37, the welding wire 35 is bent in a wave shape and further twisted to be formed into a spiral in a corrugated shape and sent out. The feeding axis is straight and the power supply is good and welding is stable.

[00019]

As described above, according to the present invention, the welding wire is formed into a small spiral shape or a corrugated shape to increase the absolute length of the wire and strengthen the toughness of the wire, and thus, in the spring liner during the wire feeding process. Spreads the feeding resistance of the robot, absorbs the feeding resistance difference caused by the posture change of the robot wrist, and stabilizes the wire feeding axis from the tip of the welding torch linearly at a constant speed.
The directivity is enhanced and the aim accuracy is improved. further,
As for the contact state with the contact tip, the wire diameter of the contact tip conventionally corresponds to the wire diameter.
The wire passage diameter is large and the contact area is increased to make it uniform over the entire circumference. The feeding point is stable and wear is reduced, so welding with a small amount of spatter is possible and the reliability of robot welding is dramatically improved.

[Brief description of drawings]

FIG. 1 is a sectional view of a wire forming apparatus of the present invention.

FIG. 2 is a mechanism diagram of another embodiment.

[Fig. 3] Partially enlarged view of the wire feeding roller

FIG. 4 is a mechanism diagram of another embodiment.

[Explanation of symbols]

 1,2. Holding plate, 3,4. Bearing, 5,6. Axial plate, 7. Toothed pulley 9. Spherical bearing, 10. Spring liner, 12, 13. Feeding roller 15. Welding wire 22, 23. Wire feeding roller, 28. Side rollers, 25. Welding wire, 32, 33. Wire feeding roller, 38, 39. Twist roller,

Claims (3)

[Claims] 1. A welding wire forming process, wherein in the wire feeding process of arc welding with a consumable wire, the wire is formed into a spiral shape with a diameter within 5 times the diameter of the wire and at a pitch of 2 times the diameter or more. apparatus. 2. In a process of feeding a wire for arc welding with a consumable wire, welding is performed by bending the wire in a circumferential direction in a wave shape at an amplitude within 5 times the wire diameter and at a pitch not less than 2 times the amplitude. Wire forming equipment. 3. In a wire feeding process of arc welding with a consumable wire, the wire is bent in a wavy shape at a constant pitch, and further spiraled at a pitch not less than 5 times the wire diameter and not less than twice the amplitude. Welding wire forming device that is bent into a shape.