JPS62197289A - Laser beam machining device - Google Patents

Abstract

PURPOSE:To reduce the weight, to improve the responsibility in position controlling and to enable the working of high accuracy by enabling the laser beam irradiation from every angle with two reflection systems. CONSTITUTION:The optical axis C of a parabolic mirror 19 is coincided with the prescribed line of the body to be worked by moving the machine head 14 on which the parabolic mirror 19 is provided. The machine head 14 is rotated with its rocking and is moved as well in X axis and Z axis directions by rotating the driving motor 17 provided on the outer peripheral part of a horizontal arm 8c. With the rocking rotation of the head 14 the optical axis C is kept vertically for the working face of the body to be worked at all times in succession and also moved vertically in Z axis direction, so the focus of the laser beam is always directed for the working face. In this way, the laser beam is held vertically for the working face of the body to be worked without changing the focus at all times only with the rocking rotation of the head 14 with moving it in X axis and Z axis directions, and the laser beam machining is performed in succession.

Description

DETAILED DESCRIPTION OF THE INVENTION [Technical Field of the Invention] The present invention relates to a laser processing apparatus suitable for continuous processing of a workpiece having a curved surface.

[Technical background of the invention and its problems] For example, Japanese Patent Application Laid-Open No. 59-21491 is known as a laser processing apparatus for welding or cutting metal plates using laser light.

This laser processing device guides a laser beam oscillated from a laser oscillator through an optical transmission system installed inside the robot arm to a condensing section installed at the tip of the robot arm. Laser processing is performed by irradiating light onto the workpiece. The bent arm member constituting the robot arm is rotatably connected to the first bent arm, which is rotatably supported around the vertical central axis by a support member. and a second bent arm, and a reflecting mirror for reflecting the laser beam is provided at each of the bent portions to constitute an optical transmission system.

Therefore, in this laser processing device, when the first bending arm is rotated with respect to the support member, the first bending arm and the second bending arm are rotated.
The bending arm of rotates about the vertical central axis, and by rotating the second bending arm with respect to the first bending arm, the second bending arm rotates about the tilted center axis, but the light condensing part rotates the second bending arm about the tilt center axis. The focal point P of the focused laser beam is constant. In other words, no matter how the bending arm member is rotated, the position of the focal point P is not changed, and the direction of irradiation of the laser beam from the condenser is naturally limited to horizontal and vertical directions.

However, in order to continuously process a workpiece with high precision, it is necessary to always maintain the laser optical axis perpendicular to the processing surface and move the laser beam focus. Therefore, when the workpiece is a curved surface, the inclination of the workpiece surface changes continuously, so when the above laser processing apparatus is used, it is necessary to simultaneously control at least four axes. Therefore, the number of moving axes increases and positioning accuracy decreases. Further, there are disadvantages in that a large number of anti-circuit systems are required in the bent arm, making adjustment of the laser optical axis complicated, and the weight of the arm increases, reducing responsiveness during positioning control.

In addition, since a glass lens is used as a light focusing means, when a high-power laser beam enters the lens, it may be damaged due to heat generation or the focal position may shift, which may impede high-power laser processing. It had become.

[Object of the Invention] This invention was made in consideration of the above circumstances, and its purpose is to reduce the number of simultaneously controlled axes and reduce the weight of the arm in continuous machining of a workpiece having a curved surface. It is necessary to provide a processing device with improved positioning performance.

[Summary of the Invention 1] In order to achieve the above object, the present invention introduces a laser beam irradiated in a vertical direction from a laser oscillator provided on a support member movable in at least one dimension into a hollow bending arm, The laser beam is rotated around the optical axis and reflected via a flat reflecting mirror installed at the bending part to a condensing parabolic mirror installed on the open side of the horizontal arm of the bending arm. By rotating this parabolic mirror around the optical axis, the laser beam is focused on the processing surface.

[Embodiment of the Invention] An embodiment of the invention will be described below with reference to FIGS. 1 to 3. 1 in Figure 1 is a device stand, and this device stand 1
An XYZ three-axis orthogonal coordinate robot 2 is provided on the rear side of the top surface. Furthermore, a workpiece 3 having a continuous curved surface 3a is fixed to the front side of the apparatus stand 1. A ZiIII support section 4 is attached to the front end of the robot 2 so as to be movable in the vertical direction. As shown in FIG. 2, a support portion 5 as a support member is fixed to the lower end of the Z-axis support portion 4. As shown in FIG. This support portion 5 is movable in the X, Y, and Z directions. A cylindrical bearing body 6 having a nonge part 6a at the upper part is fitted in front of the support part 5. A laser oscillator 7 that emits laser light along a vertical optical axis A is provided above the bearing body 6. On the other hand, a hollow cylindrical bending arm 8 is inserted into the bearing body 6 from below. The laser beam irradiated by the laser oscillator 7 is introduced into the bent arm 8. The upper part of the vertical arm 8a of the bending arm 8 has a bearing 9 mounted between it and the bearing body 6.
9 and rotates around the light f[llA. That is, a gear 10 is fixed to the outer periphery of the vertical arm 8a, and this gear 10 is rotated by meshing with a gear 12 fixed to the shaft end of an arm drive motor 11 installed on the upper surface of the support section 5. It looks like this.

The bending arm 8 is connected at a bending portion 8b to a horizontal arm 8G bent at 90 degrees with respect to the vertical arm 8a. A plane reflecting mirror 13 is attached to the bent portion 8b. A processing machine head 14 is rotatably supported by bearings 15.15 at the open end of the horizontal arm 8G. That is, a gear 16 is fixed to the outer periphery of the processing machine head. And this gear 1
6 is a pinion 18 directly connected to a drive motor 17 as a second drive motor provided on the outer periphery of the horizontal arm 8G.
When the drive motor 17 rotates, it rotates around the optical axis B in the horizontal direction as shown in FIG. 3. A parabolic mirror 19 made of copper, for example, is fixed to the end of the processing machine head 14 as a condensing parabolic mirror having a parabolic surface '19a on the front surface. This parabolic mirror 19 collects the laser light incident on the horizontal arm 8c in the plane reflecting mirror 13, and then passes the light perpendicular to the optical axis B through the irradiation port 20 provided on the processing machine head 14. It is configured to irradiate a single force plane of the workpiece 3 along the axis C.

Using the laser processing apparatus configured as described above, a corrugated workpiece 3 in which curved surfaces 3a are continuously formed is cut along the broken line 3b.
To weld in the X direction along Match.

Next, the drive motor 17 provided on the outer periphery of the horizontal arm 8G is rotated to swing and rotate the processing machine head 14 as shown in FIG. 3, and to move the processing head 14 in the X-axis and Z-axis directions. . And processing machine head 1
4 swings and rotates as shown in Fig. 3, the optical axis C is continuously maintained perpendicular to the processing surface 3b of the workpiece 3, and also moves up and down in the Z-axis direction, so that the laser beam The focus is always directed to the processing surface 3b.

Therefore, in this embodiment, after the processing machine head 14 has been moved from Cera 1 to Cera 1, the processing machine head 14 is
By simply swinging and rotating the processing machine head 14 while moving it in the axial direction, the laser beam always maintains its focus perpendicular to the processing surface 3b of the workpiece 3, so the laser output increases. By adding a cooling device,
High precision and high efficiency laser processing is possible without damage due to heat generation or change in focal length.

In the above embodiment, the support part 5 of the laser oscillator 7 is attached to the lower part of the Z-axis support part 4 of the XYZ three-axis orthogonal coordinate robot 2, but a reflection system may be provided at the orthogonal point of each axis of the robot 2. Therefore, it is also possible to eliminate the support part 5 in FIG. 2, connect the bending arm 8 directly to the Z-axis support part 2, and install the laser oscillator 7 on the apparatus stand 1.

[Effects of the Invention] As explained above, according to the present invention, the condensing optical axis is
It can be moved continuously by dimensional movement and can be continuously maintained perpendicular to the processing point, making it possible to perform highly accurate processing.

In addition, while the conventional technology requires at least four reflection systems, the present invention allows laser beam irradiation from any angle with two reflection systems, making it easy to adjust the optical axis. . Therefore, not only maintenance performance is improved, but also the weight of the arm is reduced, and responsiveness during position control is improved.

In addition, since the present invention uses a metal parabolic mirror, even if the laser output becomes large, by adding a cooling device, damage due to heat generation can be prevented, and the focal length can be changed. This makes it possible to perform highly accurate and highly efficient laser processing.

[Brief explanation of drawings]

The drawings show one embodiment of the present invention, and FIG. 1 is a perspective view showing a laser processing device, FIG. 2 is an enlarged sectional view taken in the direction of the ■ arrow in FIG. 1, and FIG. 3 is a side view in the direction of the ■ arrow in FIG. It is a diagram. 5... Support part (support member), 7... Laser oscillator,
-〇- 8...Bending arm, 8b...Bending portion, 8G...Horizontal arm, △...Optical axis (vertical direction), 11... Arm drive motor (first drive motor), 13... Plane reflecting mirror, 14... Processing machine head, 17... Drive motor (second drive motor), 19... Parabolic mirror (parabolic mirror light guide for focusing).

Claims (1)

[Claims] a first driving device that rotates a condensing parabolic mirror light guide around an optical axis in the vertical direction of the laser beam; a condensing parabolic mirror provided on the open side of the horizontal arm of the bending arm; A laser processing device comprising: a processing machine head that holds the parabolic mirror; and a second drive device that rotates the processing machine head around an optical axis.