JPH0755387B2 - Irradiation position adjustment device for laser processing lens - Google Patents

Description

TECHNICAL FIELD The present invention relates to an apparatus for adjusting the laser irradiation position of a laser processing lens used as a focusing lens in a laser processing machine in an off-machine mode.

[Prior Art] In laser processing, as shown in FIG. 7, a processing lens 1 is used to collect a laser beam 2 and its focus is on a welding line 4 or a cutting line of a workpiece 3. It is necessary to match with accuracy. Conventionally, this adjustment, since CO ₂ laser beam 2 and the like are invisible light, the workpiece 3, actually CO ₂ laser beam 2
Etc., and after welding is performed, the workpiece 3 is cut out, and a welding bead 8 as shown in FIG.
The position deviation of the jig 5 is shifted by the adjusting screw 7 attached to the jig base 6, and the welding is performed again to confirm the position deviation amount.

In addition to the above method, there is also known a method or apparatus in which a visible laser oscillation source is incorporated in a laser processing machine and the focus position of the invisible laser light is adjusted on-machine using the visible laser light ( For example, JP-A-56-119688
Japanese Patent Laid-Open No. 57-69789).

[Problems to be solved by the invention] In the case of a CO ₂ laser processing machine, the processing lens has been generally used with a non-reflective coating on the surface using ZnSe, KCl, etc. as its material. Is limited to about 500 hours and needs to be replaced in a timely manner. Also, if scattered particles, metal vapor, spatter, etc., generated from the work piece adhere to the lens surface, the processed lens may be damaged in a relatively short time, and the lens replacement work must be performed while the laser processing machine is operating. It may be necessary. However, the position of the lens center with respect to the outer circumference of the processed lens differs depending on the individual lens due to variations in processing during manufacturing.Also, the processed lens is mounted on the lens mount with the lens outer circumference as a reference, but there is a mounting error during mounting. Therefore, when the processed lens is replaced, it is almost always necessary to readjust the irradiation position.

However, in the conventional method of adjusting the irradiation position of the processed lens,
Adjustment cannot be done unless the lens is attached to the laser processing machine, so if the processing lens is damaged while the laser processing machine is operating, stop the operation and convert the lens to a new spare lens, and then It is necessary to perform the work of aligning the irradiation position, which requires a long stop time of the processing device, which is a cause of greatly reducing the work efficiency.

Further, since the CO ₂ laser light is not visible laser light, in the method shown in FIGS. 7 and 8, after actually processing the actual part, the part was cut and the positional deviation was measured. It is necessary to readjust and re-examine later. The adjustment work is a time-consuming work, and therefore, the method as described above has a problem in that when the processed lens needs to be replaced due to damage or the like, the downtime of the equipment becomes very long.

The present invention focuses on the above problems, and is an apparatus capable of extremely accurately adjusting the irradiation position of a processing lens without actually processing an actual part and in an off-machine state with respect to a laser processing machine. The purpose is to provide.

[Means for Solving the Problems] An irradiation position adjusting device for a laser processing lens according to the present invention, which meets this object, adjusts the irradiation position in advance before the laser processing lens is mounted on a laser processing machine. And has the following configuration.

That is, an optical mechanism that oscillates visible laser light and shapes the oscillated visible laser light into cylindrical light that is irradiated in parallel with a circular cross section in a circular shape, and is provided on the optical path of the cylindrical light, and laser processing is performed. Lens holder for holding a laser processing lens, which is used in a laser processing machine and collects the laser light of the laser processing machine, so as to be positionally adjustable in a plane perpendicular to the central axis of the cylindrical light and in the vertical plane, Processing lens holder holding means for holding the lens holder so that the central axis of the processed lens holder is coaxial with the central axis of the cylindrical light and rotatably in the coaxial state, and the cylindrical light is used for laser processing. It is arranged on the optical path of the transmitted light that passes through the lens and is condensed by the laser processing lens, has a light receiving surface for the transmitted light, and the center reference point of the light receiving surface is coaxial with the central axis of the cylindrical light. Processing for laser while holding Approaches the lens, the position adjustable light receiving means in a direction away, a support for supporting the above-mentioned optical mechanism, machining the lens holder holding means and on the center axis of the light receiving means cylindrical light consists.

[Operation] In such an apparatus, the processed lens for laser is held in the processed lens holder holding means while being held by the processed lens holder, and the processed lens has a visible light shaped into a cylindrical light from the optical mechanism. Laser light is emitted. The irradiated visible laser light passes through the processing lens, is condensed by the processing lens, and is applied to the light receiving surface of the light receiving means. Since the transmitted light is condensed, the transmitted light can be condensed as a condensing point on the light receiving surface by adjusting the position of the light receiving means toward and away from the processing lens. In this state, the position of the condensing point is deviated from the position of the center reference point of the light-receiving surface. Therefore, when the processing lens holder, and thus the processing lens, is rotated with respect to the processing lens holder holding means, the position of the condensing point is also changed. Rotate around the central reference point. The position of the processed lens is adjusted in the processed lens holder so that the position of the visible 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 mounted on the laser processing machine together with the processing lens holder in the adjusted state, the cylindrical shape of the laser processing machine As long as the coaxiality between the light and the processing lens holder mounting portion is ensured, the focal point of the processing lens after mounting is accurately located on the central axis of the cylindrical light in the laser processing machine. That is, in the laser processing machine, the invisible laser is accurately focused on a predetermined point, and on-machine adjustment is unnecessary.

[Embodiment] A preferred embodiment of the present invention will be described below with reference to the drawings.

1 and 2 show an irradiation position adjusting device for a laser processing lens according to an embodiment of the present invention. In the figure, 11 indicates a He-Ne laser that oscillates a He-Ne laser beam 12 as a visible laser beam. The He—Ne laser light 12 emitted from the He—Ne laser 11 is reflected by the mirror 13 and is emitted to the mirror 14. The mirror 14 is rotatable by a motor 15, and the laser light reflected from the mirror 14 is shaped into a conical light and passes through the lens 16.
By the lens 16, the laser light is shaped into a cylindrical light 17 whose cross section is irradiated in parallel with a circular ring. Therefore, these devices are configured by 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 light of the laser processing machine.
Is located. As shown in the enlarged view of FIG. 2, the laser processing lens 19 has a cylindrical light 17 inside the processing lens holder 20.
It is held perpendicularly to the central axis 21 of and in such a way that its position can be adjusted in the vertical plane. The processed lens holder 20 is a processed lens
Internal holder 22 that holds 19 from the outer peripheral surface and internal holder 22
Is constituted by an external holder 24 which holds the position of which is adjustable through two sets of four adjusting screws 23 which are orthogonal to each other. The external holder 24 has a structure in which the outer peripheral surface 25 and the end surface 26 are used as reference surfaces to be accurately attached to the processing head portion of the laser processing machine, and serves as processing lens holder holding means of the irradiation position adjusting device of the present invention. The processed lens holder holding portion 27 is accurately attached to the inner ring 28 so that the center axis of the processed lens holder 20 is coaxial with the center axis 21 of the cylindrical light 17. Inner ring
28 is rotatably supported via a bearing 29, and the processed lens holder 20 is rotatable while its rotation center is kept coaxial with the central axis 21 of the cylindrical light 17.

When the cylindrical light 17 passes through the processed lens 19, the processed lens 19
The light is condensed by 19, and a micrometer head 31 as a light receiving means is arranged on the optical path of the transmitted light 30 that is condensed. On the top surface 32 of the micrometer head, the transmitted light
The light receiving surface for 28 is formed, and the light receiving surface 32 has a cylindrical light 17
A central reference point 33 (illustrated in FIG. 4 described later) located on the central axis 21 of the is provided. This micrometer head 31
The top surface 32 of the is close to the processing lens 19 while keeping the central reference point 33 coaxial with the central axis 21 of the cylindrical light 17 as described above,
The position can be adjusted in the separating direction (vertical direction in FIG. 1).

In order to support the optical mechanism 18, the processed lens holder holder 27 and the micrometer head 31 on the central axis 21 of the cylindrical light 17 as described above, a stand 34 as a support is provided.

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

The visible laser light from the He-Ne laser device 11 is reflected by the mirror 13 and the rotating mirror 14, and is shaped into a cylindrical light 17 by the lens 16. The He-Ne laser light shaped into this cylindrical light enters the processing lens 19. The He-Ne laser light transmitted by the processing lens 19 is condensed into a conical shape and is irradiated on the light receiving surface 32 at the top of the micrometer head 31. The position of the light receiving surface 32 is adjusted so that the focused spot of the laser light on the light receiving surface 32 is minimized. In this state, as shown in FIGS. 3 and 4, the center of the inner ring 28 and the light receiving surface 32 (the center reference point 3
In contrast to 3), when the optical axis center of the processing lens 19 is deviated by Δt, the He-Ne laser light forms the focal point 35 on the optical axis of the processing lens 19, so only Δt from the center of the light receiving surface 32. It is focused at a distant position. Here, when the processed lens holder 20 is rotated together with the inner ring 28, the focus 35 of the He-Ne laser light has a radius Δ around the center reference point 33 of the light receiving surface as shown in FIG.
Draw a circle of t.

While rotating the processed lens holder 20 together with the inner ring 28,
Turn the adjusting screw 23 of the processing lens holder 20 to
Is moved together with the inner holder 22 so that the radius Δt of the circle becomes smaller. As a result of this adjustment, when the centers of the inner ring 28 and the light receiving surface 32 and the optical axis center of the processing lens 19 coincide with each other as shown in FIG. 5, the center reference point 33 of the light receiving surface 32 and the He- Even if the processing lens 19 turns the inner ring 28 when the focal point 35 of the Ne laser light coincides and the radius Δt of the circle becomes 0,
The focus of He-Ne laser light does not move.

With this adjustment, the optical axis center of the processed lens 19 can be aligned with the central axis of the mounted reference surface 25, which is always a fixed position, with respect to the mounted reference surface 25 of the processed lens holder 20.

First, the adjusted processing lens holder 20 is mounted on the laser processing machine, and once the irradiation position of the laser light is adjusted, thereafter, when the processing lens is replaced, the irradiation position of the laser processing lens of the present invention. By using the adjusting device to adjust the position of the processing lens, there is no need to make adjustments after mounting the laser processing equipment. Irradiation position adjustment of this processing lens can be performed accurately from the laser processing machine in the off-machine state using He-Ne laser light that is visible laser light. It is no longer necessary to check the laser light irradiation position and the lens replacement time is extremely short because it is an off-machine adjustment. Also, if another set of processed lens and processed lens holder is prepared and the adjustment work of the present invention is carried out in advance, when the processed lens is damaged, the adjusted lens holder and the processed lens can be replaced to immediately produce the product. Can be resumed.

[Effects of the Invention] As described above, according to the irradiation position adjusting apparatus for a laser processed lens of the present invention, the following various effects can be obtained.

Since it is an off-machine adjustment using a visible laser beam, adjustment can be performed without processing an actual part, and time-consuming cutting and cross-section checking work of a processed part is unnecessary, and the number of adjustment steps can be reduced.

Further, since it is an off-machine adjustment, it can be adjusted even while the laser processing machine is in use, the operating rate of the laser processing machine can be increased, and the processing lens replacement time can be greatly shortened.

Furthermore, since the bright spots of the visible laser light are visually adjusted, it is easy to make a determination, no skill is required for the adjustment, and extremely highly accurate adjustment is possible.

[Brief description of drawings]

FIG. 1 is a partially sectional side view of an irradiation position adjusting device for a laser processing lens according to an embodiment of the present invention, and FIG. 2 is a partially enlarged vertical sectional view of the device of FIG. FIG. 4 is a partial schematic diagram of the device of FIG. 1, showing a method for adjusting the device of FIG. 1, FIG. 4 is a plan view of the light-receiving surface of FIG. 3, and FIG. 5 is after adjustment of the device of FIG. FIG. 6 is a plan view of the light-receiving surface of FIG. 5, FIG. 7 is a partial vertical cross-sectional view of a conventional laser beam machine, and FIG. 8 is welding welded by the apparatus of FIG. It is an expanded sectional view of a part. 11 …… He-Ne laser 12 …… Laser light 13,14 …… Mirror 15 …… Motor 16 …… Lens 17 …… Cylinder light 18 …… Optical mechanism 19 …… Laser processing lens 20 …… Processing lens holder 21 …… Center axis of cylindrical light 22 …… Internal holder 23 …… Adjusting screw 24 …… External holder 25, 26 …… Reference surface 27 …… Processing lens holder holding means 28 …… Inner ring 29 …… Bearing 30 …… Transmitted light 31 …… Receiving means 32 …… Receiving surface 33 …… Center reference point 34 …… Support 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 radiated in parallel with an annular shape, and an optical mechanism provided on the optical path of the cylindrical light. A processing lens holder for holding a laser processing lens, which is used in a laser processing machine and collects laser light of the laser processing machine, so as to be positionally adjustable in a plane perpendicular to the central axis of the cylindrical light and in the vertical plane. A processed lens holder holding means for holding the processed lens holder rotatably such that the central axis of the processed lens holder is coaxial with the central axis of the cylindrical light and is rotatably in the coaxial state; Light is disposed on the optical path of transmitted light that is transmitted through the laser processing lens and condensed by the laser processing lens, has a light receiving surface for the transmitted light, and the center reference point of the light receiving surface is the cylinder. And keep it coaxial with the central axis of As it is, a light receiving means capable of position adjustment in a direction of approaching and separating from the laser processing lens, and a support body for supporting the optical mechanism, the processing lens holder holding means and the light receiving means on the central axis of the cylindrical light. Irradiation position adjustment device for laser processing lenses.