JPH01299788A - Method and apparatus by laser beam machining - Google Patents

Abstract

PURPOSE:To prevent damage of a nozzle by detecting a member to be detected existing to advancing direction of the machining nozzle with a sensor, picking up this with an image pickup device and reducing the speed of or stopping the machining nozzle based on the image processing. CONSTITUTION:A laser beam machining head 15 is fitted to a beam 11 in a column 9 as vertically shiftable, and non-contacting type sensor 19 is arranged at outer circumference of the nozzle 17. The sensor 19 is connected with the image pickup device 23, picture processor 25 and NC device 27 in order. The advancing direction and speed of the machining nozzle 17 are controlled with the NC device 27 to execute the laser beam machining. Then, when the max. detected length of the sensor 19 detects projecting part Wt of a work W, the image processor 25 reduces the speed of the nozzle 17, and when the min. detected length of the sensor 19 crosses the projected part Wt, the processor 25 stops the nozzle 17. As the collision to the work W can be avoided, the damage of the machining nozzle 17 is surely prevented.

Description

[Detailed Description of the Invention] [Object of the Invention] (Industrial Application Field) The present invention relates to a laser processing device, and more specifically, the present invention relates to a laser processing device, and more specifically, a processing nozzle attached to the tip of a processing head is The present invention relates to a laser processing method and apparatus that avoids colliding with a member to be detected in front of the laser.

(Prior Art) Conventionally, in a laser processing apparatus, a processing head is moved in the x-axis and y-axis directions by an NC device relative to a workpiece to be processed. A processing nozzle is attached to the tip of the processing head.

While laser processing is performed by irradiating the workpiece with a laser beam from the processing nozzle, the processing nozzle may hit a protrusion and be damaged.

In order to prevent damage to the processing nozzle, a contact sensor is attached to the outer periphery of the processing nozzle.

Therefore, the contact sensor detects the protrusion by hitting the protrusion.

(Problem to be Solved by the Invention) By the way, since the contact type sensor detects when it hits the protrusion, a stop command signal is issued to stop the processing nozzle from the time of detection by the contact type sensor. . Therefore, there is a problem in that coasting inevitably occurs and it is very difficult to completely prevent damage to the processing nozzle.

The purpose of the present invention is to improve the above-mentioned problems by attaching a non-contact sensor to the outer periphery of a processing nozzle, using the sensor to detect a member to be detected on one side in the direction of movement of the sensor,
It is an object of the present invention to provide a user-friendly laser processing method and apparatus for stopping a processing nozzle without causing the processing nozzle to coast.

[Structure of the Invention] (Means for Solving the Problem) In order to achieve the above object, the present invention provides a machine that moves in the X-axis and Y-axis directions relative to the workpiece to be machined and is attached to the tip. When the processing head, which has a non-contact type sensor installed on the outer periphery of the processing nozzle, moves in a predetermined direction of movement, the processing nozzle and the sensor are imaged by an imaging device, and the processing head is moved in the direction of movement of the processing nozzle and the processing nozzle. When the sensor detects a detected member in the direction of movement of the processing nozzle within a detection range determined according to the speed of the processing head, the processing head is processed by an image processing device connected to an imaging device to reduce the speed of the processing head. This is a laser processing method that stops.

The present invention also provides a processing head whose movement is controlled by an NC device relative to a workpiece to be processed in the X-axis and Y-axis directions, and a laser beam attached to the tip of the processing head to irradiate the workpiece to be processed. A processing nozzle, a non-contact sensor attached to the outer periphery of the processing nozzle, an imaging device that images the sensor and the tip of the processing nozzle, and a processing direction and processing of the processing nozzle captured by the imaging device. The speed of the processing nozzle is controlled by detecting the member to be detected in front of the processing nozzle in the direction of movement using the detection range determined according to the speed of the nozzle! ii) A laser processing apparatus including an image processing apparatus was constructed.

(Function) By employing the laser processing method and apparatus of the present invention, the processing nozzle attached to the tip of the processing head has its traveling direction and speed in the XY plane controlled by the NC device. Since a non-contact sensor is attached to the outer periphery of the processing nozzle, the direction and speed of movement of the sensor are also controlled.

In addition, the sensor and the tip of the processing nozzle are imaged by an imaging device, and when the processing nozzle moves in a predetermined direction of travel and the sensor detects a detected member in front of the processing nozzle, it is processed by the image processing device. The machining nozzle is then stopped while its speed is decelerated.

(Example) Hereinafter, an example of the present invention will be described in detail based on the drawings.

Referring to FIG. 4, the laser processing device 1 includes a work table 5 fixed on a base 3.
X to guide the workpiece W@X-Y plane (left and right plane) above
Equipped with Y carriage 7.

The XY carriage 7 is provided with a clamp device that grips the workpiece W placed on the worktable 5 and transports the workpiece W to a position directly below a processing head, which will be described later.

A column 9 extending upward from the rear end of the base 3 is erected, and a beam 11 is provided on the column 9 to project forward. A laser oscillation device @13 is attached to the rear of the column 9. A machining head 15 that is movable in the Z-axis direction (vertical direction) is attached to the lower end of the beam 11 on the ship side.

Further, a processing nozzle 17 is attached to the tip of the processing head 15, and one end of a non-contact type sensor 19 made of a plurality of conical optical fibers is attached to the outer periphery of the processing nozzle 17. . The other end of the sensor 19 is provided near the base 3, and the sensor 19
Above the other end is a C attached to the frame 21.
An imaging device 23 such as an OD camera is provided.

The image carrying device 23 is connected to an image processing device 25, and the image processing device 25 is connected to an NC device 27 that numerically controls the XY carriage 7.

The laser oscillation device 13 oscillates a carbon dioxide laser beam LB for processing, and also oscillates a visible light laser lb such as 1-1e-Nθ when adjusting the optical axis or focus of the laser beam LB.

The work table 5 is provided with a hole 29 through which the laser beam LB or visible light laser lb is transmitted. Further, the workpiece W is provided with a reference hole 31.

As shown in FIGS. 1 and 2, the advancing direction and speed of the engraving nozzle 17 are controlled by the NC device 27. In FIGS. 1 and 2, if the processing nozzle 17 moves at a velocity vector F as indicated by the arrow, then
X in the Y plane.

In the Y-axis coordinate, the velocity vectors are FX and FV, and the direction of movement of the processing nozzle 17 with respect to the X-axis is tanθ=Fy
/Fx, it advances at an angle of θ-jan-1 (Fy/Fx).

The detection range of the sensor 19 with respect to the advancing direction of the processing nozzle 17 is specified by a detection length consisting of a width along the outer shape of the processing nozzle 17. Its maximum detection length L ylax is 1a
Set +ax=F・αr7. (However, α: a constant of the detection area) Furthermore, the minimum detection length L1n is set to a predetermined length from the outer diameter of the processing nozzle 17. Thus, the detection range of the sensor 19 is determined according to the speed of the processing nozzle 17.

In FIGS. 1 and 2, it is assumed that there is a protrusion W of the workpiece W as a detected member in front of the processing nozzle 17 in the traveling direction, the processing nozzle 17 moves at a speed vector F, and the sensor 19 detects the maximum When the detection length 1 max is detected across the protrusion WT, the speed of the processing nozzle 17 is decelerated,
The processing nozzle 17 further advances and when the minimum detection length L sin of the sensor 19 is detected across the protrusion WT, the processing nozzle 17 stops to prevent the processing nozzle 17 from colliding with the protrusion Wr. This is how it was done.

The processing nozzle 17 and the sensor 19 attached to the outer periphery of the processing nozzle 17 are imaged by the imaging device 23, and the images are processed by an image processing device 25 connected to the imaging device 23.

As shown in FIG. 3, the image processing device 25 includes a binarization circuit 33, a frame memory 35, and a CPtJ
37. ROM39. RAM41. It has an input/output device 43.

The binarization circuit 33 converts the video signal, which is an analog signal, into one
．． This digital signal is digitized into a 0 code and stored in the frame memory 35 as image data. The frame memory 35 stores one pixel for each pixel corresponding to the black and white portion of the image.
, 0 signals will be stored. Let the physical coordinates of the frame memory 35 be xy. This seat Iffxy makes the coordinate (xOlyo) correspond to the mounting position (Xo, Yo) of the coordinates X and Y of the work table 5, and in the relationship of the variable position,
=Kx −x, v=ky−y. Kx,
Ky is a constant determined by the equivalent distance per pixel and the magnification of the IIE) device 23. Of course, the maximum and R-small detection lengths L1aX and Llllin are processed in correspondence with the coordinates X and Y of the frame memory 35.

The ROM 39 stores a program for performing arithmetic processing, which will be described later. The input/output device 43 is the image processing device 2
5 and the internal input/output device of the NC device 27, and is connected to the bus 45 of the NC device 27 and the internal input/output device of the NC device 27,
It serves to transmit data signals to device 27.

The RAM 41 stores the maximum detection length L wax determined by the speed vector F of the processing nozzle 17 using the formula 1IlaX=Fφα, and the preset minimum detection length L sin
is memorized.

With the above configuration, the advancing direction of the processing nozzle 17 with respect to the workpiece W to be machined by the NC device 27 is determined by the above-mentioned equation as shown in FIGS. Proceed in the direction of the arrow shown. There is a protrusion WT of the work W as a member to be detected in front of the processing nozzle 17 in the advancing direction, and the processing nozzle 17 advances to reach the maximum detection length l ma of the sensor 19.
When the tip of the x crosses the protrusion WT, the sensor 19 is actuated and detected, which is stored in the frame memory 25 via the binarization circuit 33 of the image processing device 27 and processed by the CPU 37 to determine the speed of the processing nozzle 17. A deceleration command signal is issued to decelerate. The deceleration command signal is sent to the NC device 27 via 11043, and the processing nozzle 17 is decelerated to a speed slower than the speed vector F.

Further, the decelerated processing nozzle 17 advances, and the sensor 1
When the tip of the minimum detection length L sin of 9 crosses the protrusion W■, the sensor 19 is actuated and detected, and processed in the manner described above to issue a stop command signal. The stop command signal is sent to the NC device 27 via l1043, and the processing nozzle 17 is stopped.

Therefore, even if there is a protrusion WT of the workpiece W as a member to be detected in front of the processing nozzle 17 in the traveling direction, when the processing nozzle 17 advances, the maximum and minimum values of the sensor 19 attached to the outer circumference of the processing nozzle detection length LIlaX
, Llin, the processing nozzle 17 can be stopped while decreasing its speed. Note that the processing nozzle 17 and the sensor 19 are connected to the imaging device 2.
3 and processed by the image processing device 25.

Therefore, even if there is a detected member in front of the processing nozzle 17 in the advancing direction, the detected member is detected by the sensor 19, and the processing nozzle 17 can be stopped while decelerating its speed. Therefore, it is possible to prevent the processing nozzle 17 from colliding with the detected member.

Further, since the detection range of the sensor 19 is determined according to the speed of the processing nozzle 17, the processing nozzle 1
Collision of the processing nozzle 17 with the detected member can be avoided regardless of the speed of the processing nozzle 7.

Note that this invention is not limited to the embodiments described above, but can be implemented in other forms by making appropriate changes.

[Effects of the Invention] As can be understood from the above description of the embodiments, according to the present invention, the advancing direction and speed of the processing nozzle attached to the tip of the processing head in the X-Y plane are controlled by the NC device. be done. Since a contact type sensor is attached to the outer periphery of the processing nozzle, the traveling direction and speed of the sensor are controlled together with the processing nozzle.

Moreover, the sensor and the tip of the processing nozzle are imaged by the imaging device, the processing nozzle moves in the direction of movement determined by the NC device, and when the sensor detects a detection member in front of the processing nozzle in the direction of movement, the image is processed. The processing nozzle can be processed by the device to slow down and stop the processing nozzle. Thus, it is possible to prevent the processing nozzle from colliding with the detected member.

In addition, since the detection range of the sensor is set to a predetermined range depending on the speed of the processing nozzle, it is possible to avoid colliding the processing nozzle with the detected member regardless of the speed of the processing nozzle. can.

[Brief explanation of the drawing]

Figure 1 shows a processing nozzle which is the main part of this invention. FIG. 2 is an explanatory diagram illustrating the relationship between a sensor and a protrusion of a workpiece as a member to be detected, and FIG. 2 is a sectional view taken along the line ■-■ in FIG. FIG. 3 is a block diagram of a configuration for processing a detection value when a detected member is detected by a sensor with an image processing device, and FIG. 4 is a perspective view of a laser processing device according to an embodiment of the present invention. . 1... Laser processing device 7... XY carriage 15
...Processing head 17...Processing nozzle 19...Sensor 23...Ratio imaging device 25...Image processing device 2
7...NC device agent Patent attorney Yasu Miyoshi 1...Laser processing device 7...XY*p ledge 15.
...Processing head 17...Processing nozzle 19...Sensor 23...1il ghost attack 25...Image processing device M
27...NC device! First figure formation! He- Nim/L+-1 Figure 2

Claims (2)

[Claims] (1) A processing head that moves in the X- and Y-axis directions relative to the workpiece and has a non-contact sensor on the outer periphery of the processing nozzle attached to the tip. While moving the processing nozzle and the sensor with the imaging device, the detected member located in the processing nozzle's traveling direction is detected by a detection range determined according to the processing nozzle's traveling direction and the processing nozzle's speed. 1. A laser processing method characterized in that, when detected by a sensor, processing is performed by an image processing device connected to an imaging device to reduce the speed of the processing head and stop the processing head. (2) A processing head whose movement is controlled by an NC device relative to the work to be processed in the X-axis and Y-axis directions, and a processing nozzle attached to the tip of the processing head to irradiate the work to be processed with a laser beam. , a non-contact sensor attached to the outer periphery of the processing nozzle, an imaging device that images the sensor and the tip of the processing nozzle, and the moving direction and speed of the processing nozzle captured by the imaging device. an imaging processing device that controls the speed of the processing nozzle by detecting a detected member in front of the processing nozzle with the sensor in a detection range determined according to the processing nozzle. Device.