WO2019171706A1 - Welding device and control method therefor - Google Patents

Abstract

Provided is a welding device with which it is possible to perform an input operation with respect to a welding device by a simple method, and to set a weaving direction easily even when a workpiece is disposed at an angle. The welding device is provided with: a welding torch; a drive unit for driving a welding robot; a control unit for controlling the position and operation of the drive unit; and a training data input unit for inputting data concerning an approach point (A) for the welding torch, and a weld start point (B) and a weld end point (C). The control unit determines a first vector from the weld start point (B) to the approach point (A), a second vector from the weld start point (B) to the weld end point (C), and a third vector orthogonal to the first vector and the second vector to define a weaving coordinate system, and controls the drive unit to cause the torch disposed at the weld start point (B) to be moved in the direction of the second vector while weaving in the direction of the third vector.

Description

Welding apparatus and control method thereof

(Cross-reference of related applications)
This application claims priority based on Japanese Patent Application No. 2018-042134 filed on Mar. 8, 2018, and all the contents disclosed therein are integrated into this application as a single reference. To do.

(Technical field)
The present invention relates to a welding apparatus and a control method thereof, and relates to a welding apparatus and a control method thereof that reduce an operator's burden on a weaving operation of a welding robot of the welding apparatus.

[To date, several industrial robot weaving devices have been proposed. For example, in Patent Document 1, when the three-dimensional shape of a workpiece is complicated and the weaving direction changes frequently, the appropriate weaving direction is automatically selected even if the welding progress direction or the tool direction changes. A weaving device capable of calculating and weaving is disclosed.

More specifically, the weaving device disclosed in Patent Document 1 includes a weaving coordinate system calculating unit, a traveling direction vector calculating unit that calculates a traveling direction vector of a welding line, and a change in the traveling direction vector of the welding line. When the outer product vector calculation means for calculating the outer product vector and the advancing direction vector of the weld line change, the weaving coordinate system before and after the change is rotated around the outer product vector by the angle of the trajectory change amount to create a new weaving coordinate system. Coordinate defining means for defining, and weaving means for performing weaving according to the calculated or determined weaving coordinate system.

That is, the weaving device of Patent Document 1 defines a new weaving coordinate system each time the traveling direction vector of the weld line changes, and performs weaving based on this. In other words, the weaving apparatus of Patent Document 1 must define individual weaving coordinate systems when weaving and welding workpieces having different welding direction vectors.

Patent Document 1 describes a method of creating a weaving coordinate system between a welding line and each amplitude point by teaching a weaving device, for example, a plurality of amplitude points when defining a weaving coordinate system. Point teaching type) While the degree of freedom of the swing direction and weaving shape is high, the operator has to teach multiple amplitude points, which complicates the input operation (teaching, teaching) to the weaving device and lowers work efficiency. .

On the other hand, instead of inputting the amplitude point to the weaving device, a method of defining a weaving operation by setting a parameter determined based on the welding start point has been proposed (parameter specification type). However, although this method simplifies the input operation (teaching, teaching) to the weaving device, it does not directly teach the amplitude point, so that the work is particularly inclined with respect to the horizontal plane. If it is, it is not easy to set or adjust the weaving direction (tilt adjustment).

JP-A 64-007107

Therefore, the aspect according to the present invention realizes the input operation (teaching, teaching) to the welding apparatus by a simple method, and easily sets the weaving direction even when the workpiece is disposed at an inclination. It is an object of the present invention to provide a welding apparatus and a control method thereof.

A first aspect according to the present invention relates to a welding apparatus, and the welding apparatus includes a welding torch, a drive unit that drives a welding robot to which the welding torch is attached, and a control that controls the position and operation of the drive unit. And a teaching data input unit for inputting data relating to the approach point (A), the welding start point (B), and the welding end point (C) of the welding torch, and the control unit includes the welding unit A first vector from the start point (B) to the approach point (A), a second vector from the welding start point (B) to the welding end point (C), the first vector, and the A third vector orthogonal to the second vector is obtained, a weaving coordinate system is defined, and the welding torch arranged at the welding start point (B) is moved in the direction of the third vector. While weaving I, controls the drive unit so as to move along the direction of the second vector.

The second aspect of the present invention relates to a control method for a welding apparatus, which includes a step of setting an approach point (A) of a welding torch, a welding start point (B), and a welding end point (C). A first vector from the welding start point (B) to the approach point (A), a second vector from the welding start point (B) to the welding end point (C), and the first Determining a vector and a third vector orthogonal to the second vector and defining a weaving coordinate system; and the welding torch arranged at the welding start point (B), Moving along the direction of the second vector while weaving along the direction.

The amplitude, pitch, and height of the weaving may be input by the user using the teaching data input unit.

The input operation (teaching, teaching) to the welding apparatus can be realized by a simple method, and the weaving direction can be easily set even when the workpiece is arranged at an inclination.

It is a block diagram showing a schematic structure of a welding device concerning an embodiment of the present invention. Horizontal fillet welding (fillet welding) in which welding is performed along the weld line while weaving about the weld line (X-axis) where the first plate (standing plate) and the second plate (lower plate) abut each other It is a schematic perspective view which shows the control method. It is a side view when it cut | disconnects in the vertical cross section of FIG. It is a flowchart which shows the welding control method which concerns on embodiment of this invention. FIG. 4 is a side view similar to FIG. 3 when the second plate is inclined by an inclination angle θ with respect to the horizontal direction. It is a schematic perspective view which shows the groove welding along a weld line using the welding control method which concerns on this embodiment.

Embodiments of a welding apparatus according to the present invention will be described below with reference to the accompanying drawings. In the description of the embodiments, a term indicating a direction (for example, “X, Y, Z”, etc.) is used as appropriate for easy understanding, but this is for explanation, and these terms are used in the present invention. It does not limit.

FIG. 1 is a block diagram showing a schematic configuration of a welding apparatus 1 according to an embodiment of the present invention. The welding apparatus 1 includes a welding torch 10, a welding robot drive unit 12 that drives a welding robot to which the welding torch 10 is attached, a control unit 20 that servo-controls the position and operation of the welding robot drive unit 12, and a user welding. A teaching data input unit (also referred to as a teaching data interface) 22 for setting a weaving coordinate system of the torch 10, a welding power source 24 connected to the control unit 20 and supplying a power source for generating a discharge arc in the welding torch 10; Is provided.

FIG. 2 shows a horizontal corner where welding is performed along a weld line while weaving about a weld line (X-axis) where the first plate (standing plate) 32 and the second plate (lower plate) 34 abut each other. It is a schematic perspective view which shows the control method of meat welding (it is also called fillet welding). 3 is a cross-sectional view taken along a cross section perpendicular to the X direction of FIG. FIG. 4 is a flowchart showing a welding control method according to the embodiment of the present invention.

In step ST01 of the flowchart of FIG. 4, as shown in FIG. 3, the position where the welding torch 10 is arranged close to the workpiece 30, that is, the approach point (A) is set by the user using the teaching data input unit 22. Is set. The setting or teaching of the approach point (A) is performed by any welding apparatus other than the present invention, and does not specifically limit the present invention. The teaching data input unit 22 is used to set or input a welding start point (B) for starting welding by arc discharge and a welding end point (C) for ending welding.

In step ST02, the control unit 20 includes a first vector (hereinafter referred to as “BA vector” for convenience) from the welding start point (B) to the approach point (A), and a welding end point from the welding start point (B). A second vector reaching (C) (for convenience, hereinafter referred to as “BC vector”) is defined. That is, the control unit 20 according to the present embodiment defines the Z axis in the direction along the BA vector and defines the X axis in the direction along the BC vector.

Next, in step ST03, the control unit 20 obtains a third vector (for convenience, hereinafter referred to as “W vector”) in a direction orthogonal to the BA vector and the BC vector, and defines the Y axis in a direction along the third vector. To do. The W vector is obtained as an outer product of the BA vector (Z-axis direction) and the BC vector (X-axis direction) (W vector = BA vector × BC vector). Thus, the control unit 20 defines the XYZ weaving orthogonal coordinate system irrespective of the arrangement relationship between the first plate 32 and the second plate 34.

In the XYZ weaving orthogonal coordinate system of this embodiment, the W vector (Y-axis direction) defines the weaving deflection direction. In step ST04, the teaching data input unit 22 is used to set parameters such as a weaving amplitude (amplitude) D and a weaving cycle distance, that is, a peak-to-peak distance (pitch) P, as shown in FIG. Entered.

In step ST05, the control unit 20 performs pitching along the BC vector (X direction) while weaving the welding torch 10 with an amplitude D in a direction parallel to the W vector (Y axis direction) during workpiece welding. Welding is performed by moving with.

In step ST04, in addition to the weaving amplitude D and pitch P, although not shown in detail, the user uses the teaching data input unit 22 to change the first plate 32 and the second plate 34 from the welding start point (B). The height in the Z-axis direction up to the weld line (X-axis) that is abutted with each other may be set. The welding torch 10 of FIG. 2 is illustrated so as to weave a sawtooth locus on the XY plane, but is not limited to this, and is a U-shaped, sinusoidal, or helical locus. The user may set using the teaching data input unit 22 in step ST04 so as to perform the above weaving.

In the above description, the welding torch 10 is weaved in a direction parallel to the W vector (Y-axis direction) (FIG. 3), but an arc or parabola that protrudes toward the welding line in the YZ plane. In step ST04, the user may set using the teaching data input unit 22 so as to perform weaving on a locus such as.

The advantages of the welding control method according to the present embodiment will be described below with reference to FIG. The first plate 32 and the second plate 34 to be welded are not necessarily arranged in the vertical direction and the horizontal direction. For example, as shown in FIG. There is a case where it is inclined by an inclination angle θ. In such a case, in the conventional welding control method, it is necessary to calculate or set the inclination angle θ as a parameter. When one workpiece includes many portions having different inclination angles θ, it is necessary to set a large number of reference points in order to obtain the inclination angle θ, increasing the burden on the operator's setting input (teaching).

However, according to the welding control method according to the present embodiment, as described above, the first plate can be obtained simply by inputting the approach point (A), the welding start point (B), and the welding end point (C). Regardless of the positional relationship between the first plate 32 and the second plate 34 (regardless of the inclination angle θ of the second plate 34 with respect to the horizontal direction), an XYZ weaving orthogonal coordinate system is defined. Since the plate 34 can be welded, the burden on the operator can be greatly reduced.

Although not shown, when the first plate 32 is inclined with respect to the second plate 34, the XYZ weaving rectangular coordinate system is similarly defined, and the first plate 32 and the second plate 34 are similarly defined. Can be welded, so that it is possible to save the operator from setting input.

FIG. 6 is a schematic perspective view showing groove welding (also referred to as groove welding) along the weld line using the welding control method according to the present embodiment. In step ST01, the approach point (A), the welding start point (B), and the welding end point (C) are set or input by the user using the teaching data input unit 22.

In step ST02, the control unit 20 obtains the BA vector and the BC vector, and defines the Z axis in the direction along the BA vector and the X axis in the direction along the BC vector.

In step ST03, a W vector orthogonal to the BA vector and the BC vector is obtained, and the Y axis is defined in the direction along the W vector. Thus, the control unit 20 defines the XYZ weaving orthogonal coordinate system regardless of the arrangement relationship of the workpieces.

In step ST04, the teaching data input unit 22 is used to set parameters such as the weaving amplitude D and pitch P by the user.

In step ST05, the control unit 20 follows the BC vector (X direction) while weaving the welding torch 10 with the amplitude D and the pitch P in the direction parallel to the W vector (Y axis direction) at the time of workpiece welding. Welding is performed by moving the

In FIG. 6, the welding torch 10 is illustrated as weaving a sawtooth locus on the XY plane, but may be set to weave on a U-shaped, sinusoidal, or spiral locus. Good. In addition, the welding torch 10 is weaved in a direction parallel to the W vector (Y-axis direction). May be set.

As described above, according to the welding control method according to the present embodiment, even when the workpiece to be welded is inclined by the inclination angle θ with respect to the horizontal direction, the approach point (A), By simply inputting the welding start point (B) and the welding end point (C), the XYZ weaving orthogonal coordinate system can be defined regardless of the arrangement relationship of the workpieces. Can be reduced.

The present invention can be used for a welding apparatus that can easily set a weaving direction and a control method thereof.

DESCRIPTION OF SYMBOLS 1 ... Welding apparatus 10 ... Welding torch 12 ... Welding robot drive part 20 ... Control part 22 ... Teaching data input part 24 ... Welding power supply 30 ... Workpiece 32 ... 1st plate 34 ... 2nd plate

Claims (4)

1. Welding torch,
   A drive unit for driving a welding robot to which the welding torch is attached;
   A control unit for controlling the position and operation of the driving unit;
   A teaching data input unit for inputting data regarding the approach point (A) of the welding torch, the welding start point (B), and the welding end point (C),
   The control unit includes a first vector from the welding start point (B) to the approach point (A), a second vector from the welding start point (B) to the welding end point (C), The third vector orthogonal to the first vector and the second vector is determined to define a weaving coordinate system, and the welding torch arranged at the welding start point (B) is defined as the third vector. A welding apparatus that controls the drive unit to move along the direction of the second vector while weaving along the direction of the vector.
2. The welding apparatus according to claim 1, wherein the amplitude and pitch of the weaving are input using the teaching data input unit.
3. Setting a welding torch approach point (A), a welding start point (B) and a welding end point (C);
   A first vector from the welding start point (B) to the approach point (A), a second vector from the welding start point (B) to the welding end point (C), and the first vector Determining a third vector orthogonal to the second vector and defining a weaving coordinate system;
   Moving the welding torch arranged at the welding start point (B) along the direction of the second vector while weaving the welding torch along the direction of the third vector. Control method.
4. The method for controlling a welding apparatus according to claim 3, further comprising a step of setting an amplitude and a pitch of the weaving.

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