JPH04187374A - Torch rotating device for arc welding equipment rotating at high speed - Google Patents

Abstract

PURPOSE:To optionally change an arc rotating diameter by constituting an eccentric rotary body of an outside rotary body without eccentricity and an inside eccentric ring which are separated into two and making the rotating diameter of a welding arc changeable by exchange of this ring. CONSTITUTION:When the quantity of eccentricity of the eccentric rotary body 10 when the lower end of an electrode carries out circular motion, the distance from a fulcrum of the electrode to a supporting part by the eccentric rotary body and the distance from the fulcrum of the electrode to the tip of an electrode wire are denoted by (d), (l) and L, respectively the rotating diameter at the tip of the electrode wire, in other words, the rotating diameter D of the arc is given by the following expression. D=L/(l)X2d. Accordingly, when several. kinds of eccentric rings with the different quantity (d) of eccentricity are prepared, even if the distance (l) is fixed, the rotating diameter D of the arc can be changed freely only by changing the eccentric ring. Consequently, the total length of the electrode becomes short and the size and weight of the whole of a torch can be reduced. In addition, consequently, robotization of this welding torch can be favorably promoted.

Description

DETAILED DESCRIPTION OF THE INVENTION [Field of Industrial Application] The present invention relates to a welding torch rotation device used in a high-speed rotating arc welding device, and particularly to a mechanism for adjusting the rotational diameter of a welding arc.

[Prior Art] High-speed rotating arc welding equipment performs arc welding while applying high-speed circular motion (rotation) to the arc generated between the electrode wire and the workpiece. For example, as shown in Japanese Unexamined Patent Application Publication No. 62-104684, the device is equipped with an eccentric gear that applies circular motion to the lower end of the electrode, with the upper part (the end on the electrode wire insertion side) serving as a fulcrum for the electrode through which the electrode wire passes through the center. The structure is such that the middle part of the electrode is supported by the electrode, and the lower end of the electrode is rotated.

This will be explained more specifically. FIGS. 4(A) and 4(B) are a schematic cross-sectional side view of the torch rotating device disclosed in the above-mentioned publication and a cross-sectional plan view of an eccentric gear portion that rotates the torch. As shown in the figure, the electrode wire 21 is fed through the center of the electrode 20, and the workpiece 31 is fed through the center of the electrode 20.
An arc 30 is generated between the two and welding is performed. The electrode 20 is supported at the upper part by a self-aligning ball bearing 27, and at the middle part by an eccentric gear 25 via a self-aligning ball bearing 26, and this eccentric gear 25 is attached to the shaft 23 of the motor 22. It meshes with the gear 24 that has been rotated. As a result, the lower end of the electrode 20 performs a circular motion by the eccentric rotation of the self-aligning ball bearing 26 and the eccentric gear 25 at the intermediate portion, using the support provided by the upper self-aligning ball bearing 26 as a fulcrum. The eccentric gear 25 is rotatably supported within the gear box 28 by a bearing 34. In addition, in order to supply power to the electrode wire 21, the electrode 2
A power supply cable 29 is connected to the upper end of the 0 with a bolt 33.

The amount of eccentricity of the eccentric gear 25 is set to a constant value d, and the self-aligning ball bearing 26 and the eccentric gear 25 cause the electrode 20
Since the lower end of the electrode 20 performs circular motion using the upper self-aligning ball bearing 27 as a fulcrum, the electrode wire 21 is placed at the lower end of the electrode 20.
The tip performs a circular motion around the diameter. In other words, the arc 30 rotates at high speed at a radius of 1/2×D with respect to the welding line. As a result, penetration into the groove sidewall increases, the bead surface is smoothed, and a good bead shape is obtained. At the same time, by detecting the arc voltage and welding current at the rotational position of the rotating arc 30, the arc itself can be used as a sensor. This arc sensor can be used to perform groove tracing control with high precision (Japanese Patent Publication No. 63-03934).
No. 6, Japanese Patent Publication No. 57-91877).

By the way, it is necessary to adjust the rotational diameter of the tip of the electrode wire 21 according to the width of the groove, but this rotational diameter adjustment is performed by the self-aligning ball bearing 27 that serves as the fulcrum and the self-aligning ball bearing that provides eccentricity. This is done by changing the distance g between 26,
For this purpose, a rotation diameter adjuster 32 is provided.

[Problems to be Solved by the Invention] However, in the adjustment method using the rotary diameter adjuster 32, as the adjustment range of the rotary diameter becomes larger, the rotary diameter adjuster 32 becomes longer, and the welding torch becomes longer, weighs more, and becomes larger. . Particularly recently, there has been an increasing demand for robotized welding torches, and in this case, increasing the size and weight of the torch will have a significant impact on the rigidity, strength, cost, etc. of the robot, so there is a strong desire for a smaller and lighter torch. Ta.

On the other hand, without using the rotation diameter adjuster 32, the eccentric gear 25
In the method of changing the rotation diameter by changing the eccentricity d of the eccentric gear, replacing the eccentric gear 25 itself is very troublesome, and when installing the eccentric gear 25, the rotation diameter is changed by changing the eccentricity d of the eccentric gear. It became necessary to readjust the reference positioning between the motor 22 that detects the rotational position signal and the encoder (not shown) coaxially located (this reference positioning is necessary for the groove tracing control using the arc sensor). be)
However, this readjustment was inconvenient and took a lot of time and effort.

The present invention has been made to solve the above-mentioned problems, and eliminates the need for readjustment to align the reference position with the encoder, and makes the torch smaller and lighter.
It is an object of the present invention to provide a torch rotation device for a high-speed rotating arc welding device that can easily change the diameter of the arc and nine rotations.

, [Means for Solving the Problems a] In order to achieve the above object, the torch rotation device of the high speed rotating arc welding device according to the present invention has the upper end of the electrode (electrode wire insertion side end i) as a fulcrum, and the middle The eccentric rotating body is supported by an eccentric rotating body which is rotationally driven to give circular motion to the lower end of the electrode, and circular movement is given to the welding arc at the tip of the electrode wire passing through the center of the electrode, wherein the eccentric rotating body is supported by two eccentric rotating bodies.
It consists of a separate outer rotating body without eccentricity, such as a normal gear, and an inner eccentric ring that is detachably inserted into the rotating body, and by replacing the eccentric ring. The rotation diameter of the welding arc can be changed.

[Function] When the lower end of the telephone performs a circular motion as described above, if the distance from the point to the tip of the electrode wire is L, then what is the rotational diameter at the tip of the electrode wire? The rotation diameter of the arc is given by the following equation. , , ■ Therefore, if several types of eccentric rings with different eccentricity d are prepared, the rotational diameter of the arc can be freely changed even if the distance g is constant by simply replacing the eccentric ring. Therefore, the total length of the electrode is shortened, and the entire torch can be made smaller and lighter.

Further, when replacing the eccentric ring, there is no need to remove the outer rotating body without eccentricity, so there is no need to perform reference position alignment with the encoder again when replacing the eccentric ring.

[Embodiment] Fig. 1 is a schematic sectional side view showing an embodiment of the torch rotation device of the present invention, Fig. 2 is a sectional view taken along the line A-A in Fig. 1, and Figs. 3 (A) and (B). 1 is a plan view and a sectional view of an eccentric ring. In these figures, the same members as in FIG. 4 are designated by the same reference numerals, and their explanations will be omitted.

In this embodiment, the eccentric rotating body 10 includes an outer rotating body without eccentricity, that is, a normal gear 1, and an inner eccentric that is removably inserted into the gap between the inner side of the gear 1 and the self-aligning ball bearing 26. It is composed of two rings 2.

Several types of eccentric rings 2 with different eccentricities d are prepared in order to make the rotational diameter variable according to the formula <1), and are used by replacing them as necessary. The eccentric ring 2 is positioned by engaging a notch 4 provided at its tip with a protrusion 5 projecting from a stepped portion directly opposite the gear 1. As a result, the eccentric ring 2 having an arbitrary amount of eccentricity d is connected to the outside of the self-aligning ball bearing 26,
It fills the gap with the inside of gear 1 and is inserted closely. Therefore, the outer rotating body 1 without eccentricity and the eccentric ring 2 are fixed by the protrusion 5 and the notch groove 4.

The gear 1 is rotatably supported by a bearing 34 within a gear box 28, which is a fixed member, as in the conventional example, and is rotationally driven by a drive gear 24 of a motor 22. In addition,
The drive mechanism using the gears 1 and 24 is merely an example, and the rotating body 1 can also be rotationally driven using a timing belt, a chain, or the like. In the figure, 7 is a self-aligning ball bearing 26
The mounting is an insulating member that electrically insulates the rotating mechanism portion including the self-aligning ball bearing 26 from the electrode 20 and holds the self-aligning ball bearing 26 at a predetermined position on the electrode 20. A similar insulating member 8 is also provided for the self-aligning ball bearing 27 that constitutes the fulcrum of the electrode 20. Although these insulating members 7.8 are omitted in FIG. 4, they are provided in the same way.

By configuring as described above, the self-aligning ball bearing 27
The circular motion of the lower end of the electrode 20 with the fulcrum is performed in the same manner as in the conventional case, and in addition, the conventional rotary diameter adjuster 32 (see FIG. 4)
is no longer necessary, and the rotational diameter of the arc 30 can be changed by simply replacing the eccentric ring 2 as appropriate. The distance g between the rotation fulcrum 27 and the self-aligning ball bearing 26 is set to a constant distance, and from equation (1), the rotation diameter can be changed simply by changing the eccentricity d of the eccentric ring 2. Compared to the changing method using the rotational diameter adjuster 32, the entire torch is smaller and lighter, and the eccentric ring 2 can be replaced using the gear 1. This can be done without removing the self-aligning ball bearing 26, etc., and it does not affect the meshing position of gear 1 and gear 24, so the reference positioning with the encoder (not shown) that detects the rotational position signal of the arc sensor is first performed. This is convenient because readjustment every time the eccentric ring 2 is replaced is unnecessary.

[Effects of the Invention] As described above, according to the present invention, the rotating diameter of the arc can be arbitrarily changed by simply replacing only the eccentric ring, and the entire torch can be made smaller and lighter. Therefore, robotization of the present welding torch can be advantageously advanced.

In addition, the eccentric ring is easy to replace, and there is no need to remove the outer non-eccentric rotating body or self-aligning ball bearing, making it extremely convenient as there is no need to readjust the reference alignment for the arc sensor. It is highly effective.

[Brief explanation of drawings]

FIG. 1 is a schematic cross-sectional side view showing one embodiment of the torch rotating device of the present invention, FIG. 2 is a cross-sectional view taken along the line A-A in FIG. 1, and FIGS. Plan view and sectional view, 4th
Figures (A) and (B) are a schematic cross-sectional side view of a conventional torch rotating device and a cross-sectional plan view of its eccentric rotating portion. 1... External rotating unit without eccentricity (gear) 2... Eccentric ring 10... Eccentric rotating body ゛20... Electrode - 21... Electrode wire 22... Motor 24... Gear 26... Self-aligning ball bearing 27... Self-aligning ball bearing 28... Gear box 30... Welding arc agent Patent attorney Muneharu Sasaki Figure 3 Figure 2 Figure 4--44:

Claims (1)

[Scope of Claims] The upper end of the electrode (the end on the side where the electrode wire is inserted) is used as a fulcrum, and the middle part is supported by an eccentric rotating body that is rotationally driven to give a circular motion to the lower end of the electrode, so that the center of the electrode is In a high-speed rotating arc welding device that gives a circular motion to a welding arc at the tip of a passing electrode wire, the eccentric rotating body is composed of two separated outer rotating bodies with no eccentricity and an inner eccentric ring, A torch rotation device for a high-speed rotary arc welding device, characterized in that the rotation diameter of the welding arc can be changed by replacing a ring.