JPS63180391A - Projecting position adjusting device for work lens for laser - Google Patents

Abstract

PURPOSE:To adjust the laser light projection position of a work lens by off machine by arranging the work lens for laser on the optical path of the visible laser light shaped in a cylindrical light and adjusting so that a focus point may become in the same axis as the center axis of the cylindrical light with giving a rotation to the lens. CONSTITUTION:The visible laser light 12 oscillated by an He-Ne laser device 11 is shaped in a cylindrical light 17 by the optical mechanism 18 consisting of a mirror 13, rotary mirror 14 and lens 16. The cylindrical light 17 is made incident on the work lens 19 for laser held on a work lens holder holding means 27 to project a condensed transmission light 30 on the photodetection face 32 of a photodetecting means 31. At this time the transmission light 30 is condensed as a condensing point on the photodetecting face 32 by adjusting the position of the photodetecting means 31. The condensing point by the lens 19 is adjusted so as to become the same axis as the center axis of the cylindrical light 17 with rotating the work lens holder 20. The projection position of the work lens can thus be adjusted in an off machine state for a laser machine.

Description

[Detailed description of the invention] [Industrial application field] The present invention can be used as a condensing lens in a laser processing machine.

The present invention relates to a device for off-machine adjustment of a laser irradiation position by a laser processing lens used.

[Prior Art] In laser processing, as shown in FIG. 7, a processing lens 1 is used to focus a laser beam 2, and the focus is set on a welding point I! of a workpiece 3. It is necessary to precisely match the position with respect to 4, the cutting line, etc. Conventionally, this adjustment was performed by actually irradiating the workpiece 3 with the C02 laser light 2, etc., performing welding, and then cutting out the workpiece 3, since the C02 laser light 2, etc. is invisible light. There is a method in which the amount of positional deviation is read from the weld bead 8 in the cross section as shown in FIG. It has been taken.

In contrast to the above methods, there is also a known method or device that incorporates a visible laser oscillation source into a laser processing machine and adjusts the focal position of the invisible laser beam on-machine using the visible laser beam ( For example, JP-A-56-11
9688, JP-A-57-69789).

[Problems to be solved by the invention] In the case of a CO□ laser processing machine, the processing lens is 1nse, K
Conventionally, materials such as CI with anti-reflective coating applied to the surface have been commonly used, but their lifespan is only 50 years.
It has a limited lifespan of about 0 hours and requires timely replacement. In addition, if flying objects, metal vapor, spatter, etc. generated from the workpiece adhere to the lens surface, the processed lens may be damaged in a relatively short period of time, making it impossible to replace the lens while the laser processing machine is operating. Sometimes it is necessary. However, the position of the lens center relative to the outer periphery of a processed lens differs depending on the individual lens due to variations in processing during manufacturing, and processed lenses are mounted on the lens mount based on the lens outer periphery, but there are mounting errors when mounting. Partly because of that,
When changing the processed lens, it is almost always necessary to readjust the irradiation position.

However, with the conventional method of adjusting the irradiation position of processed lenses,
Adjustments cannot be made without attaching the lens to the laser processing machine, so if the processing lens is damaged while the laser processing machine is in operation, stop its operation, replace the lens with a new spare one, and then replace the lens. Currently, a port is required to perform the work of aligning the irradiation position, which results in a long downtime of the processing equipment, which is a cause of a significant drop in work efficiency.

Also, since CO2 laser light is not visible laser light,
In the methods shown in FIGS. 7 and 8, it is necessary to actually process the actual part, cut the part, measure the positional deviation, and then readjust and re-investigate. Adjustment work is time-consuming, and therefore, in the above method, there is a problem in that when the processed lens becomes damaged and needs to be replaced, the equipment will have to be stopped for a very long time.

The present invention has focused on the above-mentioned problems, and has developed a device that can extremely accurately adjust the irradiation position of a processing lens without actually processing actual parts and in an off-machine state for a laser processing machine. The purpose is to provide

[Means for Solving the Problems] The irradiation position adjustment device for a laser processing lens of the present invention that meets this purpose adjusts the irradiation position of the laser processing lens in advance before it is mounted on a laser processing machine. It consists of the following structure.

That is, an optical mechanism that oscillates visible laser light and shapes the emitted visible laser light into a cylindrical light whose cross section is circular and is irradiated in parallel; a processing lens holder that holds a laser processing lens used in a laser processing machine and condensing the laser beam of the laser processing machine so as to be adjustable in position perpendicular to the central axis of the cylindrical light and within the perpendicular plane; processing lens holder holding means for holding the processing lens holder so that the center axis of the processing lens holder is coaxial with the center axis of the cylindrical light and rotatable in the coaxial state; It is arranged on the optical path of the transmitted light that passes through the laser processing lens and is focused by the laser processing lens, and has a light receiving surface for the transmitted light, and the center reference point of the light receiving surface is set as the central axis of the cylindrical light. a light receiving means whose position can be adjusted in directions approaching and away from the laser processing lens while being held coaxially with the lens, and a support that supports the optical mechanism, the processing lens holder holding means, and the light receiving means on the central axis of the cylindrical light. It consists of and .

[Function] In such a device, the laser processing lens is held in the processing lens holder holding means in a state where it is held by the processing lens holder, and the processing lens receives a cylindrical beam from the optical mechanism. Visible laser light is irradiated. The irradiated visible laser light passes through the processing lens, is condensed by the processing lens, and is irradiated onto the light-receiving surface of the light-receiving means. Since the transmitted light is condensed, the transmitted light can be focused on the light receiving surface as a condensing point by adjusting the position of the light receiving means in the direction toward or away from the processing lens. In this state, the position of the condensing point and the center reference point of the light-receiving surface are different from each other, so when the machining lens holder, and therefore the machining lens, is rotated relative to the machining lens holder holding means, the position of the condensing point also changes. Rotate around the central reference point. The position of the processing lens is adjusted within the processing lens holder so that the position of this visible light condensing point matches the position of the central reference point. Since the central reference point is previously arranged on the central axis of the cylindrical light, in the adjusted state, the condensing point is located on the central axis of the cylindrical light of the visible laser. Since this visible laser cylindrical light and the central axis of the processing lens holder are coaxial, if the processing lens is attached to the laser processing machine along with the processing lens holder in the state after the above-mentioned alignment, the cylindrical beam in the laser processing machine can be As long as the coaxiality between the cylindrical light and the processing lens holder attachment section is ensured, the focal point of the attached processing lens will be precisely located on the central axis of the cylindrical light in the laser processing machine. In other words, in the laser processing machine, the invisible laser is accurately focused on a predetermined point, eliminating the need for on-machine adjustment.

[Embodiments] Preferred embodiments of the present invention will be described below with reference to the drawings.

1 and 2 show an irradiation position adjustment device for a laser processing lens according to an embodiment of the present invention. In the figure, reference numeral 11 indicates a He-He laser that emits 1ie-He laser light 12 as visible laser light. H
The He-He laser beam 12 irradiated from the e-Ne laser 11 is reflected by the mirror 13 and irradiated onto the mirror 14 . The mirror 14 is rotatable by a motor 15, and the laser beam reflected from the mirror 14 is shaped into a conical beam and passes through a lens 16. The laser beam is shaped by the lens 16 into a cylindrical beam 17 whose cross section is circular and irradiated in parallel. Therefore, these devices constitute the optical mechanism 18 in the present invention.

On the optical path of the cylindrical light 17, a laser processing lens 19 that is used in a laser processing machine and focuses the laser beam of the laser processing machine is positioned. As shown in an enlarged view in FIG. 2, the laser processing lens 19 is held in a processing lens holder 20 perpendicular to the central axis 21 of the cylindrical light 17, and its position can be adjusted within the perpendicular plane. be done. Processed lens holder 20
is an internal holder 2 that holds the processed lens 19 from the outer peripheral surface.
2, and two sets of four adjustment screws 2 perpendicular to the internal holder 22.
3, and an external holder 24 that is held in a position adjustable manner. The external holder 24 has an outer peripheral surface 25
The inner ring of the processing lens holder holding portion 27 serves as a processing lens holder holding means of the irradiation position adjustment device of the present invention. 28, the processing lens holder 20 is mounted with high precision so that its central axis is coaxial with the central axis 21 of the cylindrical light 17.

The inner ring 28 is rotatably supported via a bearing 29, and the processed lens holder 20 is rotatable while keeping its rotation center coaxial with the central axis 21 of the cylindrical light 17.

When the cylindrical light 17 passes through the processing lens 19, it is focused by the processing lens 19, but this focused transmitted light 3
A micrometer head 3 as a light receiving means is placed on the optical path of 0.
1 is arranged. Top surface 32 of micrometer head
The light receiving surface 32 constitutes a light receiving surface for the transmitted light 28.
A central reference point 33 (shown in FIG. 4, which will be described later) is provided on the central axis 21 of the cylindrical light 17. The top surface 32 of this micrometer head 31 is moved in the direction toward and away from the processing lens 19 (up and down in FIG. The position can be adjusted in the direction).

In order to support these optical mechanism 1B, processing lens holder holding section 27, and micrometer head 31 on the central axis 21 of the cylindrical light 17, a stand 34 as a support is provided.

In such an apparatus, the irradiation position of the laser processing lens is adjusted as follows.

A visible laser beam from a He-Ne laser device 11 is reflected by a mirror 13 and a rotating mirror 14, and is shaped into a cylindrical beam 17 by a lens 16. 1 shaped into this cylindrical light
The ie-Ne laser beam enters the processing lens 19.

The tl e -N e laser beam transmitted by the processing lens 19 is focused into a conical shape, and the micrometer head 31
The light is irradiated onto the light-receiving surface 32 at the top of the . The position of the light receiving surface 32 is adjusted so that the focused spot of the laser beam on the light receiving surface 32 is minimized. In this state, as shown in FIGS. 3 and 4, if the optical axis center of the processing lens 19 is shifted by 8t with respect to the center of the inner ring 28 and the light receiving surface 32 (center reference point 33), He Since the -Ne laser beam focuses 35 on the optical axis of the processing lens 19, it
The light is focused at a position t apart.

Here, when the processing lens holder 20 is rotated together with the inner ring 28, the focus 3 of the He-Ne laser beam is
5 draws a circle with radius Δt centered on the central reference point 33 of the light receiving surface.

While rotating the processing lens holder 20 together with the inner ring 28, the adjustment screw 23 of the processing lens holder 20 is turned to move the processing lens 19 together with the internal holder 22, and adjust the radius of the circle in the direction in which t becomes smaller. With this adjustment, as shown in FIG. 5, when the centers of the inner ring 28 and the light-receiving surface 32 coincide with the center of the optical axis of the processed lens 19, the central reference point 33 of the light-receiving surface 32 and He The focal points 35 of the -Ne laser beams coincide, the radius Δt of the circle becomes O, and even if the processing lens 19 turns the inner ring 28, the focal point of the He-Ne laser beams does not move.

With this adjustment, the mounting reference surface 25 of the processing lens holder 20
On the other hand, the optical axis center of the processed lens 19 can be made to coincide with the central axis of the mounting reference surface 25, which is always at a constant position.

First, this adjusted processing lens holder 20 is attached to the laser processing machine, and once the laser beam irradiation position is adjusted, from then on, when replacing the processing lens, the irradiation position of the laser processing lens of the present invention will be adjusted. By adjusting the position of the processing lens using the adjustment device, adjustment after installing the laser processing equipment becomes unnecessary.

This adjustment of the irradiation position of the processing lens can be performed with high accuracy off-machine from the laser processing machine using a He-Ne laser beam, which is a visible laser beam, so it is possible to weld the actual parts. There is no need to check the laser beam irradiation position, and since the adjustment is off-machine, the time required for lens replacement is extremely short. In addition, if you prepare another set of processed lenses and processed lens holders and perform the adjustment work of the present invention in advance, if the processed lenses are damaged, you can immediately start production by replacing the processed lenses together with the adjusted lens holder. can be restarted.

[Effects of the Invention] As explained above, when using the laser processing lens irradiation position adjustment device of the present invention, the following various effects can be obtained.

Off-machine adjustment using visible laser light allows adjustment without machining the actual part, eliminates the need for time-consuming cutting of processed parts and cross-section checking, and reduces the number of man-hours required for adjustment.

Furthermore, since it is an off-machine adjustment, it can be adjusted even while the laser processing machine is in use, increasing the operating rate of the laser processing machine and significantly shortening the time required to replace the h-loe lens.

Furthermore, since the bright spot of the visible laser beam is adjusted visually, it is easy to distinguish, no skill is required for adjustment, and adjustment can be made with extremely high precision.

[Brief explanation of the drawing]

1 is a partially sectional side view of an irradiation position adjustment device for a laser processing lens according to an embodiment of the present invention; FIG. 2 is a partially enlarged vertical sectional view of the device shown in FIG. 1; The figure is a partial schematic configuration diagram of the device in Figure 1, showing how to adjust the device in Figure 1. Figure 4 is a plan view of the light-receiving surface in Figure 3. Figure 5 is after adjustment of the device in Figure 3. Fig. 6 is a plan view of the light-receiving surface shown in Fig. 5, Fig. 7 is a partial vertical cross-sectional view of a conventional laser processing machine, and Fig. 8 shows a welding process performed using the device shown in Fig. 7. This is an enlarged sectional view of the section. 11......tl e -N e laser 12
......Laser beam 13.14...Mirror 15...Motor 16...Lens 17... Cylindrical light 18... Optical mechanism 19... Laser processing lens 20...
...Processed lens holder 21...
Central axis of cylindrical light 22...Inner holder 23...Adjustment screw 24...External holder 25.26...Reference plane 27... Processing lens holder holding means 28
......Inner ring 29...Bearing 30...Transmitted light 31...Light receiving means 32... ...... Light-receiving surface 33 ...... Center reference point 34 ...... Support body 35 ...... Focus

Claims (1)

[Claims] (1) an optical mechanism that oscillates visible laser light and shapes the oscillated visible laser light into cylindrical light whose cross section is circular and is irradiated in parallel; a processing lens holder that holds a laser processing lens used in a processing machine and condensing the laser beam of the laser processing machine so as to be adjustable in position perpendicular to the central axis of the cylindrical light and within the perpendicular plane; processing lens holder holding means for rotatably holding the processing lens holder such that the center axis of the processing lens holder is coaxial with the center axis of the cylindrical light and in the coaxial state; It is disposed on the optical path of the transmitted light that passes through the laser processing lens and is focused by the laser processing lens, and has a light receiving surface for the transmitted light, and the center reference point of the light receiving surface is set to the cylindrical light beam. a light receiving means whose position can be adjusted in a direction toward and away from the laser processing lens while being held coaxially with the central axis of the cylindrical light; and a light receiving means whose position can be adjusted in a direction toward and away from the laser processing lens; A device for adjusting the irradiation position of a laser processing lens, comprising: a support supported on the substrate;