JPH0788656A - Device for controlling cutting operation of cutting robot - Google Patents

Abstract

PURPOSE:To simplify a teaching operation for a cutting robot. CONSTITUTION:A data showing a distance Zp between a piercing height Prp and a cutting height P is set as a condition for cutting. In addition, a route to the piercing height is not taught, but only a route to the cutting height Q4 is taught. At the time of a playback, the tip 2a of a tool is moved to the cutting height P along the taught route Q4. Then the tip 2a of the tool is moved upward in the vertical direction by the distance Zp that is shown in the data on the condition for cutting. At that time, the tip 2a of the tool is at the piercing height Prp, at this height a piercing hole is put through. Further, the tip 2a of the tool is moved downward in the vertical direction by the distance Zp shown in the data. At this time, the tip 2a of the tool is positioned at the cutting height P, this height a specific graphic is cut out.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a device for controlling the operation of a cutting robot so that a piercing hole is made to penetrate through a work before cutting.

[0002]

2. Description of the Related Art In a plasma cutting machine, the tool tip of a cutting robot is positioned at a piercing height higher than the cutting height to prevent the plasma arc from reaching the tool tip for a predetermined penetration time in order to prevent the consumption of the nozzle due to the bounce of dross. By forming it between the work and the work, the work of penetrating the piercing hole on the work is performed. Then, after that, the tool tip is moved to the cutting height to cut a predetermined figure.

The teaching of such a cutting operation is carried out as shown in FIG.

That is, as shown in FIG. 1, a path is taught until the tip of the torch 1 which is a tool, that is, the tip surface 2a of the nozzle 2 reaches the work starting point P1. The path Q1 to the piercing height P2 is then taught.
Then, "cutting start" is taught, and along with this, cutting conditions, that is, arc current values and the like are set. Then, the path Q2 to the cutting height P3 is taught. Then, the route Q3 to the cutting end point P4 along the figure R to be cut is taught.

During playback, the torch tip is moved to the work starting point P1 along the taught path, and then moved to the piercing height P2 along the taught path Q1. Here, under the cutting conditions set above in response to the "start cutting" command, the plasma arc causes the tool tip 2a to move.
And a work W are formed between the piercing holes H.
Then, the tool tip 2a is further moved to the cutting height along the teaching path Q2. Then, under the cutting conditions set above, while forming a plasma arc between the tool tip 2a and the work W, the tool tip 2a is moved along the path Q3 to the cutting end point P4, and the cutting of the predetermined figure R is completed. To do.

As described above, in the prior art, in order to bring the tool tip 2a to the two positions of the piercing height P2 and the cutting height P3, the teaching of the path Q1 up to the piercing height P2 and the cutting height P2 are taught. It was necessary to teach the route Q2 up to P3.

[0007]

As described above, when there are two types of paths to be taught, it is apparent that the teaching work is troublesome and the work efficiency is not good.

The present invention has been made in view of the above circumstances, and the teaching of the piercing height and the cutting height teach only one of them to move and cut to the piercing height position. The purpose is to facilitate teaching work by enabling movement to a height.

[0009]

Therefore, according to the present invention,
Before the cutting operation, the cutting processing conditions of the cutting robot are set and the moving path of the tool tip of the cutting robot is taught, and at the time of playback, the set cutting processing condition and the taught moving path are set. On the basis of the cutting robot, the cutting robot is controlled to move the tool tip to the piercing height to penetrate the piercing hole and then move the tool tip to the cutting height to cut a predetermined figure. In the cutting operation control device, the cutting processing conditions include distance data indicating a distance between the piercing height and the cutting height, and teach only a moving path up to the cutting height, At the time of playback, the tip of the tool is moved to the cutting height based on the teaching content, and the cutting processing condition is further set. Based on the distance data is moved by the distance the tool tip to the vertically upward performs through the pierced hole, and so that the tool tip the distance is moved downward in the vertical direction to cut the predetermined shape,
The cutting robot is controlled.

[0010]

With this structure, the distance data indicating the distance between the piercing height and the cutting height is set as the cutting processing condition. Then, the path to the piercing height is not taught, but only the path to the cutting height is taught.

During playback, the tool tip is moved to the cutting height along the taught path. Then, the tip of the tool is moved vertically upward by a distance indicated by the data of the cutting processing conditions. At this time, the tip of the tool is at the piercing height, and the piercing hole is penetrated at this height. Further, the tool tip is moved vertically downward by the distance shown in the above data. At this time, the tool tip is at the cutting height, and a predetermined figure is cut at this height.

As described above, the teaching is only required to reach the cutting height, and the movement to the piercing height is automatically controlled based on the distance data set as the cutting processing condition. Can be simplified.

[0013]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS A cutting operation control device for a cutting robot according to the present invention will be described below with reference to the drawings. A cutting robot (not shown) of the embodiment is, for example, a 6-axis vertical articulated robot, and a tool 1 which is a plasma torch is attached to the arm tip as shown in FIG. 2 (a). A nozzle 2 is formed at the tip of the tool 1, and a plasma flow is emitted from the opening of the tip surface 2a of the tool 1 to form a plasma arc between the tip surface 2a and the work W which is the material to be cut. It

Each axis of such a cutting robot is driven and controlled by a controller (not shown). The content of work performed by the cutting robot is determined by previously teaching the movement path of the tool tip position 2a and setting cutting conditions such as arc current value and gas pressure. The teaching is
This is performed by remotely operating the robot with a teaching box (not shown). The cutting conditions are also set by operating the teaching box. The teaching contents and the setting contents of the cutting conditions are sent from the teaching box to the controller. At the time of playback, based on the teaching contents and the cutting conditions, the controller performs the cutting process such that the tool tip 2a is moved along the taught path and the gas pressure and the arc current value set as the cutting conditions. The robot axes and the plasma power source are driven and controlled so that

In such a cutting robot, in order to prevent the consumption of the nozzle due to the bounce of the dross, the tool tip 2a of the cutting robot is positioned at a piercing height Prp higher than the cutting height P and the plasma arc 3 is kept at the tool tip for a predetermined penetration time. By forming it between the work 2a and the work W, the work of penetrating the piercing hole on the work W is performed (see FIG. 2B). Then, after that, the tool tip 2a
Is carried out to the cutting height P and a predetermined figure is cut (see FIGS. 2 (c) and 2 (d)).

The teaching for performing such a series of cutting operations is performed as follows. (1) Teaching the path to the cutting height In the same way as shown in FIG. 3, the path to the tip 2a of the tool 1 to the work starting point P1 is taught. Then, as shown in FIG. 2A, a route Q4 from the work starting point P1 to the cutting height P is taught.

(2) Teaching of "cutting start" and setting of piercing movement amount Next, "cutting start" is taught. This is taught in order to execute the piercing movement processing shown in FIG. 1 in response to a "disconnect start" command during playback.

Along with the teaching of "cutting start", cutting conditions, that is, arc current value, gas pressure, etc. are set.
In this embodiment, a distance between the cutting height P and the piercing height Prp (hereinafter referred to as "piercing movement amount") Zp is set as the cutting condition, in addition to the above-mentioned data such as the arc current value. The cutting conditions are set to appropriate values according to the plate thickness, material, etc. of the work W. The piercing movement amount Zp is used as data when executing the piercing movement processing shown in FIG.

(3) Teaching of Path to Cutting End Point Next, as in the case of FIG. 3, a path Q3 to the cutting end point P4 along the figure R to be cut is taught.

As described above, the teaching does not need to teach the path up to the piercing height and the path up to the cutting height as in the prior art. As shown in (1) above,
Since it is only necessary to teach the path up to the cutting height, teaching work can be performed easily and efficiently.

The playback operation is performed as follows.

That is, first, the controller drives and controls each axis of the robot so that the tool tip 2a is moved to the work starting point P1 along the path taught in (1) above. Then, each axis of the robot is drive-controlled so that the tool tip 2a is moved to the cutting height P along the path Q4 taught in (1) above (see FIG. 2A).

Then, the piercing movement process shown in FIG. 1 is started in response to the "cut start" command taught in (2) above.

That is, as shown in FIG. 1, the current position data P indicating the cutting height and the tool posture matrix M indicating the current posture of the tool 1 are fetched. The current position data P and the posture matrix M are calculated based on the detected values of the current position of each axis of the robot, and P = (x, y, z, A, B, C, SP). Is expressed as Here, x, y, z are coordinate positions of the tool tip 2a in the work occupancy system, A, B, C are attitude angles of the tool 1, and SP determines the current position of each axis of the robot. Structural parameters for (step 10
1).

Next, of the data set in the above (2), the piercing movement vector ΔZp is calculated based on the piercing movement amount Zp as ΔZp = [0, 0, -Zp] T. And this piercing movement vector ΔZp
Based on the current tool attitude matrix M and ΔPrp = M · ΔZp = [Δxrp, Δyrp, Δzrp], the pierce movement vector ΔPrp in the working coordinate system is obtained. Then, based on the obtained piercing movement vector ΔPrp and the current position (cutting height) P obtained in step 101, Prp = P + ΔPrp = [x + Δxrp, y + Δyrp, z + Δ
zrp, A, B, C, SP] is performed to obtain the pierce movement target position in the work coordinate system, that is, the pierce height Prp (step 102).

Next, each axis of the robot is drive-controlled so that the tool tip 2a is moved to the target position Prp calculated in the above step 102 (step 103).

As a result, the tool tip 2a is positioned at the piercing height Prp. At this position, the arc is turned on and the current command is output under the cutting condition set in the above (2). Then, the plasma arc 3 is formed between the tool tip 2a and the work W, and the pierce hole is penetrated (see FIG. 2B; step 104).

Then, each robot axis is drive-controlled so that the tool tip 2a is moved to the current position (cutting height) P obtained in step 101 (step 10).
5; see FIG. 2 (c).

When the piercing movement process is completed in this way, the teaching content of (3) above is then played back. That is, under the cutting condition set in the above (2), while the plasma arc 3 is formed between the tool tip 2a and the work W, the tool tip 2a is moved along the path Q3 to the cutting end point P4. As described above, each axis of the robot is drive-controlled to cut a predetermined figure (see FIG. 2).
(D)).

Thus, during playback, the movement to the cutting height is controlled based on the teaching content Q4, and the movement to the piercing height is controlled based on the piercing movement amount Zp given as the cutting condition. .

When the piercing movement amount Zp is set to 0 as the cutting condition, the piercing movement process of steps 101 to 105 is not performed, and the cutting process is performed at the cutting height together with the "cutting start" command. Will be seen.

Further, in the above-described embodiment, only the path Q4 up to the cutting height is taught. However, conversely, only the path Q5 up to the piercing height may be taught. Work can be simplified. In this case, the following steps 101 'to 104' may be executed instead of steps 101 to 105 in FIG. In this case as well, the movement amount Z ′ from the piercing height to the cutting height is given as the cutting condition similarly to the piercing movement amount Zp.

That is, the operation during playback will be described. First, the tip of the tool is moved to the piercing height according to the teaching content Q5. Then, in step 101 ′, the piercing hole penetration processing is executed.

Step 102 'The position data P'of the piercing height is fetched.

Step 103 'The target position of the cutting height is calculated based on the movement amount Z'given as the cutting condition.

Step 104 'The movement to the target position is executed.

Further, in the embodiment, the values of the movement amounts Zp and Z'are set directly, but since the values of the movement amount differ depending on the plate thickness, the material, etc. of the work W, the kind of work is preliminarily set. It is also possible to store the relationship between the movement amount and the movement amount in the memory, and to read out and set the corresponding movement amount from the memory by specifying the type of work.

Further, in the embodiment, the case of plasma cutting is described as an example, but of course, the present invention can be applied to any cutting robot such as a robot that cuts with a YAG laser.

[0039]

As described above, according to the present invention,
Teaching work can be simplified because movement to the piercing height position and movement to the cutting height can be performed by teaching only one of the teaching of the piercing height and the teaching of the cutting height. As a result, the burden on the operator is greatly reduced and the work efficiency is dramatically improved.

[Brief description of drawings]

FIG. 1 is a flow chart showing an embodiment of a cutting operation control device for a cutting robot according to the present invention, showing a process of moving a tool tip from a cutting height to a piercing height and further moving to a cutting height. It is a flowchart shown.

FIG. 2A to FIG. 2D are diagrams showing a cutting operation according to an embodiment.

FIG. 3 is a diagram used for explaining a state of a conventional cutting operation.

[Explanation of symbols]

 1 Tool (torch) 2 Nozzle 2a Tool tip surface 3 Plasma arc W work

Claims (2)

[Claims] 1. Before cutting work, the cutting condition of the cutting robot is set, the moving path of the tool tip of the cutting robot is taught, and at the time of playback,
Based on the set cutting processing conditions and the taught movement path, the tool tip is moved to the piercing height to penetrate the piercing hole, and then the tool tip is moved to the cutting height to set a predetermined value. In a cutting operation control device for a cutting robot that controls the cutting robot so as to cut a figure, the cutting processing conditions include distance data indicating a distance between the piercing height and the cutting height, and Only the movement path up to the cutting height is taught, and at the time of playback, the tool tip is moved to the cutting height based on the teaching content, and further the tool is based on the distance data of the cutting processing conditions. Move the tip vertically upward by the above distance to penetrate the pierce hole, and move the tool tip vertically downward. The distance moved so as to cut the predetermined shape, the cutting operation control unit of the cutting robot for controlling the cutting robot. 2. Before cutting work, the cutting condition of the cutting robot is set, the moving path of the tool tip of the cutting robot is taught, and at the time of playback,
Based on the set cutting processing conditions and the taught movement path, the tool tip is moved to the piercing height to penetrate the piercing hole, and then the tool tip is moved to the cutting height to set a predetermined value. In a cutting operation control device for a cutting robot that controls the cutting robot so as to cut a figure, the cutting processing conditions include distance data indicating a distance between the piercing height and the cutting height, and Only the moving path up to the piercing height is taught, and at the time of playback, the tip of the tool is moved to the piercing height to penetrate the piercing hole based on the teaching content, and the cutting processing condition Based on the distance data, move the tool tip vertically downward by the distance and cut a predetermined figure. So that the cutting operation control unit of the cutting robot for controlling the cutting robot.