JP2707348B2 - Laser processing machine and control method thereof - Google Patents

Description

Description: TECHNICAL FIELD The present invention relates to a laser beam machine and a control method thereof.

2. Description of the Related Art Conventionally, in a drilling of a sheet metal by a laser processing machine, a movable range of a laser irradiation nozzle is determined by determining a stroke limit by a parameter or by providing a limit switch in a hardware manner on the laser irradiation nozzle. Was.

Problems to be Solved by the Invention However, in these conventional methods, when the thickness of the sheet metal of the processed workpiece is large, or when the sheet thickness changes,
Alternatively, when the sheet metal is warped, the laser irradiation nozzle may come into contact with the sheet metal. In such a case,
The adjustment of the optical axis of the laser is lost, and the optical axis needs to be adjusted again.

Therefore, an object of the present invention is to provide a laser beam machine capable of protecting a laser irradiation nozzle even when the sheet thickness is changed or the sheet metal is warped, and a control method therefor.

Means for Solving the Problems The present invention, in order to achieve the object, a copying sensor provided in a laser irradiation nozzle, a control device that inputs a signal from the copying sensor, and an output from the control device, A laser irradiation nozzle driving unit for driving a laser irradiation nozzle, wherein the control device performs a control other than a copying process, and a signal that a distance between the laser irradiation nozzle and the workpiece is equal to or less than a predetermined value. In this case, the laser irradiation nozzle driving means is stopped when an input is made from the controller.

Therefore, according to the present invention, the program for performing the limit check of the laser irradiation nozzle is provided to the control means of the numerical control device provided in the laser processing machine without changing the laser processing machine in hardware at all. The laser irradiation nozzle can be protected simply by adding a laser beam.

Embodiment Hereinafter, an embodiment of the present invention will be described with reference to the drawings.
FIG. 1 shows a schematic configuration of an embodiment of the present invention. Although a contact type copying apparatus that is generally used is shown in the figure, the copying apparatus may be a contact type or a non-contact type.

In FIG. 1, reference numeral 1 denotes a laser irradiation nozzle which guides a laser beam and moves up and down to focus an internal condenser lens. Reference numeral 2 denotes a scanning sensor provided on the laser irradiation nozzle 1. Reference numeral 3 denotes a scanning sensor. Probe as a contact, 4
Is a sheet metal which is a material to be processed, 5 is a control means for receiving an output from the copying sensor 2 to perform copying control and limit checking of the laser irradiation nozzle 1, and 6 is a laser irradiation nozzle driving means for driving the laser irradiation nozzle 1. .

The control means 5 includes, in addition to the conventional copying control program,
When the laser irradiation nozzle 1 is not performing the scanning control, the area from the scanning sensor 3 to the laser irradiation nozzle 1 where the distance between the laser irradiation nozzle and the workpiece is equal to or less than a predetermined value (hereinafter, this area is referred to as an “overtravel area”). "), The laser irradiation nozzle 1
There is a program to stop the movement.

The tip 3a of the probe 3 of the scanning sensor 2 is located below the tip 1a of the laser irradiation nozzle 1 and is formed in a ring shape having a diameter larger than the diameter of the tip 1a. At the time of the copying control, the tip 3a of the probe 3 follows the surface shape of the sheet metal 4 by contacting and copying the surface of the sheet metal 4,
So that the laser beam always focuses on a predetermined position on the sheet metal 4
The laser irradiation nozzle 1 is driven up and down. That is, if the surface of the sheet metal 4 has irregularities, the probe 3 moves up and down, and the copying sensor 2 detects the up and down movement so that the laser irradiation nozzle 1 is positioned at an equilibrium point within a certain moving range.
Controls the laser irradiation nozzle driving means 6.

When performing the limit check of the laser irradiation nozzle 1, as shown in FIG. 2, it is first determined in step 11 whether or not the copying control is being performed. If the copying control is not being performed, then in step 12 It is determined whether the laser irradiation nozzle 1 is moving horizontally or vertically. Then, in step 13, the laser irradiation nozzle 1 is moving,
When it is determined from the copying sensor 2 that the laser irradiation nozzle 1 has entered the overtravel region, the movement of the laser irradiation nozzle 1 is stopped in step 14.

That is, as shown in FIG.
During the scanning control, the output of the scanning sensor 2 that changes due to the movement of the probe 3 is controlled by the control unit 5 so as to be at the equilibrium point a within a predetermined amplitude range R1. At the time of checking, the scanning sensor 2 detects that the probe 3 has entered the overtravel region R2 outside the amplitude range R1, and the control device 5 instructs the laser irradiation nozzle driving means 6 to output the laser irradiation nozzle 1 based on the output. Stop.

Next, an actual control example will be described with reference to FIG. 4 and FIG. FIG. 4 shows a case where the right side of the sheet metal 4 is warped upward. When the laser irradiation nozzle 1 moves to the right, the tip 1a of the laser irradiation nozzle 1 conventionally warps to the right of the sheet metal 4. Although the optical axis adjustment is lost due to the collision with the portion 4a, in this embodiment, the tip 3a of the probe 3 moves largely upward upon hitting the warped portion 4a of the sheet metal 4, and this is detected by the scanning sensor 2, so that the control is performed. Means 5
The laser irradiation nozzle 1 is stopped by the command of the above, and the laser irradiation nozzle 1 is prevented from hitting the sheet metal 4 beforehand.

Further, as shown in FIG. 5, when the metal plate 4 is thicker than the set one, and conventionally, when the laser irradiation nozzle 1 is lowered, the tip 1a of the laser irradiation nozzle 1
However, in this embodiment, before the tip 1a of the laser irradiation nozzle 1 hits the sheet metal 4, the tip 3a of the probe 3 hits the sheet metal 4 and moves largely upward. Since the detection is performed and the control unit 5 stops the laser irradiation nozzle 1, it is possible to prevent the tip 1a of the laser irradiation nozzle 1 from hitting the sheet metal 4 beforehand.

Effects of the Invention As described above, according to the present invention, a scanning sensor provided in a laser irradiation nozzle, a control device that inputs a signal from the copying sensor, and a laser irradiation nozzle driven by an output from the control device Laser irradiation nozzle driving means, the control device, as a control other than during the copying process, when a signal that the distance between the laser irradiation nozzle and the workpiece material is less than a certain value is input from the copying sensor The laser irradiation nozzle drive means is stopped in advance, so that the laser processing nozzle can be protected by simply adding a simple program to the control means of the conventional numerical controller without changing the laser machine in hardware. Can be easily performed.

[Brief description of the drawings]

FIG. 1 is a schematic partial configuration diagram of a laser processing machine showing one embodiment of the present invention, FIG. 2 is a flowchart showing a control procedure in one embodiment of the present invention, and FIG. 3 is an output characteristic of a scanning sensor in the same device. FIG. 4, FIG. 4 and FIG. 5 are explanatory diagrams showing control examples in the same device. Reference numeral 1 denotes a laser irradiation nozzle, 2 denotes a copying sensor, 3 denotes a probe, 4 denotes a sheet metal, 5 denotes a control means, 6 denotes a laser irradiation nozzle driving means.

Claims (2)

(57) [Claims] A scanning sensor provided on a laser irradiation nozzle;
A control device that inputs a signal from the scanning sensor, and a laser irradiation nozzle driving unit that drives a laser irradiation nozzle by an output from the control device, wherein the control device performs control other than during copying. A laser processing machine for stopping the laser irradiation nozzle driving means when a signal that makes the distance between the laser irradiation nozzle and the work material equal to or less than a predetermined value is input from the scanning sensor. 2. A control method for performing a copying process by inputting a signal from a copying sensor provided in a laser irradiation nozzle to a control device. A control method for a laser processing machine that stops a laser irradiation nozzle when a signal that causes a distance to be equal to or less than a predetermined value is output from a scanning sensor.