JPH02255291A - Device for observing position to be irradiated with laser light - Google Patents

Abstract

PURPOSE:To easily observe the position to be irradiated with laser light without exchanging a correction lens for visible light for observation by providing a housing part for members for observing the position to be irradiated with the laser light vertically movably in the laser light transmission path between a laser light total reflecting mirror and a condenser lens. CONSTITUTION:The laser light 2 is sent through the transmission part to the total reflecting mirror 3 and the condenser lens 4 and is projected from a nozzle 23 to a work 5a to process the work. The housing part 6 for a television camera 13, a change-over mirror 8 and the correction lens 14 is mounted between the total reflecting mirror 3 and the condenser lens 4 by freely vertically expandable and contractable transmission pipes 24A, 24B and the visible light 10 from a light source 9 is projected to the work 5a via a semi-permeable mirror 11, the correction lens 14 and the change-over mirror 8. The position to be irradiated with laser light is then observed. The housing part 6 is properly driven in a vertical direction by a pulse motor 22 to position the housing part 6 to attain the specified image formation position without changing the lens 14 when the focal distance of the lens 4 varies in this constitution.

Description

[Detailed Description of the Invention] [Object of the Invention] (Industrial Field of Application) The present invention aims to adjust the position of a laser beam irradiated onto a workpiece by
I! The present invention relates to a device for detecting a laser beam irradiation position.

(Prior Art) In FIG. 5 showing an example of a conventional laser processing device, a laser beam 2 emitted from a laser oscillator 1 is bent downward by a total reflection mirror 3 provided at the tip of a transmission path (not shown). The light is focused by a condenser lens 4 and irradiated onto a workpiece 5a placed on an X-Y table 5 from a nozzle (not shown).

By the way, in such a laser processing device, X-
When driving the Y table to cut out a workpiece from a standard length material, there is no need to observe the irradiation position of the laser beam 2. It is necessary to monitor whether the

FIG. 6 is a diagram in which such a laser beam irradiation position Mm device 6 is installed between the total reflection mirror and the condensing mirror at the tip of the laser transmission line 2, and the left side of the pedestal 7 on the X-Y table (not shown) A base 7b is attached to the base 7b, and a slide table 7a is attached to the base 7b so as to be movable in the vertical direction via a guide 7c.The slide table 7a stores a television camera, a correction lens, a switching mirror, etc., which will be described later. The section 6a is attached.

FIG. 7 is a diagram showing the components constituting this laser beam irradiation position observation device 6 and their arrangement. a switching mirror 8 and a correction lens 14 provided in the storage section 6a.
and a semi-transparent mirror 1 provided on the right side of this correction lens 14.
1, a television camera 13, an illumination lamp 9 that is provided adjacent to the semi-transparent mirror 11 and irradiates visible light 10 onto the semi-transparent mirror 11, and a separate camera control box 1 connected to the television camera 13.
5 and a monitor television 16 connected to this camera control box 15.

Here, when observing the position of the laser beam irradiated onto the workpiece 5a, the visible light 10 of the illumination lamp 9 is bent downward by the semi-transmissive mirror 11 and the total reflection mirror 8 protruding into the transmission path 2a.
The condensing lens 4 condenses the light and irradiates it onto the workpiece 5a. Then, this reflected light forms an image with the condensing lens 4, but the position of the television camera 13 is set so that the reflected light is corrected with the correction lens 14 and focused on the image receiving section of the television camera 13.

That is, in FIG. 8 showing the relative distance relationship of these parts, the distance between the workpiece 5a and the condensing lens 4 is designated as a, and the distance between the condensing brick 4 and the imaging position P of the visible light 10 of the condensing lens 4 is designated as b. If the focal length of the condensing lens 4 for visible light 10 is f□, then b = -(',"yo+yo=yo)...■afyoa-fi abf.

Similarly, the imaging position P by the condenser lens 4 and the correction lens 1
If the distance between C1 and the imaging position 0 by the correction lens 14 is d, and the focal length of the correction lens 14 for visible light 10 is f2, then d=cf', 1
1 1 ('','-+ ---)...■ c-f2 cdf2 Also, ρ between the condenser lens 4 and the correction lens 14 is R=b+c
...■■t(2)+■ From the formula, f2Q (a-f,)-af1f2 d=! 1-f2a-f, -af,""'If you transform this, it becomes: Include = "ichi--two colors-...■ a-f1 d-f.

(Problems to be Solved by the Invention) In laser processing, when the type of workpiece or processing method changes, the focal length may need to be changed. However, in the conventional laser beam irradiation position II detection device, the correction lens 14 is fixed in the storage part 6a, so when the imaging position @Q by the correction lens 14 is fixed, the correction lens 14
It becomes necessary to change the focal length f2 by replacing the focal length f2 (see equation (A)). This not only increases the number of correction lenses, but also takes time to make adjustments during installation.

SUMMARY OF THE INVENTION An object of the present invention is to provide a laser beam irradiation position observation device that allows the laser beam irradiation position to be easily observed even if the focal length of the condensing lens changes without replacing the correction lens.

[Structure of the invention]

(Means and Effects for Solving the Problems) The present invention focuses a laser transmission line in which a switching mirror for laser beam AM, a correction lens, and a storage section for a television camera are attached to a table that moves up and down on a pedestal. In a laser beam irradiation position observation device that is connected between a transmission line between a mirror and a reflecting mirror that transfers laser light to this focusing mirror, a moving mechanism that moves the storage section up and down is provided on the table, and the focusing mirror and reflecting mirror are By adjusting the distance between the condensing lens and the correction lens by making the transmission path between them telescopic, the irradiation position of the laser beam irradiated onto the workpiece can be adjusted without having to replace the correction lens even if the focal length of the condensing lens is changed. This is a laser beam irradiation position observation device that allows you to see the

(Example) Hereinafter, an example of the laser beam irradiation position [6 device] of the present invention will be described with reference to the drawings. However, parts that overlap with FIGS. 5 to 8 are omitted.

In FIG. 1, a guide rail 19 is attached to the left side of a slide table 7a vertically attached to the left side of the pedestal 7, and a linear guide 20 is fitted to the left side of the guide rail 19 so as to be vertically movable. A pulse motor 22 is vertically attached to the upper end of the slide table 7a as shown in FIG.
A ball screw 21 whose upper and lower ends are supported by bearings (not shown) in 1a is mounted vertically, and the upper end of the ball screw 21 is connected to the output shaft of a pulse motor 22 via a joint (not shown).

Further, a bearing 21b that is driven up and down by the rotation of the ball screw 21 is fitted into the ball screw 21, and on the left side of this bearing 21b is a storage section 6 in which a correction lens, a switching mirror, a television camera, etc. are stored. The attached base 6b is fixed, and both sides of the base 6b are guided by upper and lower linear guides 20 and guide rails 19.

Further, the nozzle 23 is fixed to the lower end of the slide table 7a via a support 23a, and a transmission tube 24 which is vertically expandable and retractable is provided between the nozzle 23 and the storage section 6 and between the total reflection mirror 3 and the storage section 6.
A, 24B is installed.

Furthermore, as shown in FIG. 2, the output side of a separately installed positioning control device 18 is connected to the input side of the pulse motor 22.
A stop position calculation device 17 is connected to the other side of this positioning control device 18, and the focal length f2 of the correction lens 14 and the imaging position d by the correction lens 14 are input in advance into this stop position calculation unit 17. has been done.

Next, when observing the position of the laser beam irradiated onto the workpiece 5a using the laser beam irradiation position observation device having such a configuration, first, as shown in the flowchart of FIG. 3, the focal length Mf of the condenser lens 4 and , the distance a between the condenser lens 4 and the workpiece 5 is input to the stop position calculation device 17. Then, the focal length f□ of the condensing lens 4 for visible light is calculated, and the distance Q between the correction lens 14 and the condensing lens 4 corresponding to the condensing lens 4 is calculated (see formula 0), and the result is The signal is output to the positioning control device 18 to drive the pulse motor 22 and drive the storage unit 6 up and down, so the storage unit 6 is positioned so that its imaging position remains constant without replacing the correction lens 14. .

In addition, in the above embodiment, the storage section 6 is the stop position calculation device 1.
71 The positioning controller 18 drives the pulse motor 22 for automatic positioning, but when the number of condensing lenses 4 is small, the position of the storage section 6 relative to the focal length of each condensing lens may be determined in advance. You can also calculate it and manually move it to that position.

That is, in FIG. 4 showing the structure, a support 7b fixed to the front surface of the lower end of the slide table 7a is provided with ball screws 21 above and below whose lower ends are supported by bearings (not shown) in the support 7b. A bearing (not shown) fixed to the back surface of the base 6b is fitted into the intermediate portion of the screw 21, and the shaft of the handle 25 is fitted into the lower end of the ball screw 21.

〔Effect of the invention〕

As described above, according to the present invention, a television camera for adjusting the irradiation position of the laser beam irradiated onto the workpiece, a switching mirror, and a storage section for the correction lens are connected to a laser transmission line attached to a table that moves up and down on a pedestal. In a laser beam irradiation position observation device connected between a condensing mirror and a transmission line between a reflecting mirror that transfers laser light to the condensing mirror, a moving mechanism is provided on the table to move the storage section up and down, and the condensing mirror is The transmission line between the mirror and the reflector is extendable and the distance between the condenser lens and the correction lens can be adjusted, so even if the focal length of the condenser lens is changed, the beam can be irradiated onto the workpiece without having to replace the correction lens. It is possible to obtain a laser beam irradiation position viewing device that allows easy viewing of the laser beam irradiation position.

[Brief explanation of drawings]

FIG. 1 is a side view showing an embodiment of the laser beam irradiation position observation device of the present invention, FIG. 2 is a detailed view of a portion of FIG. 1, and FIG. 4 is a side view showing another embodiment of the laser beam irradiation position observation device of the present invention, FIG. 5 is a diagram showing a laser processing device equipped with a conventional laser beam observation device, and FIG. 6 is a side view showing an example of a conventional laser beam irradiation position i detection device,
FIGS. 7 and 8 are diagrams showing the operation of the conventional laser beam irradiation position 1i1111 apparatus. 4... Condensing lens 6... Laser beam irradiation position wt detection device 7... Mount 7a... Slide table 8... Switching mirror 13... Television camera 9... Visible light source 14... Correction lens 2 Ball screw 22...Pulse motor

Claims (1)

[Scope of Claims] A laser transmission path in which a TV camera for observing the irradiation position of the laser beam irradiated onto the workpiece, a switching mirror, and a storage section for the correction lens are attached to a table that moves up and down on a pedestal above the workpiece. In the laser beam irradiation position observation device connected between the transmission line between the condensing mirror and the reflecting mirror that transfers the laser beam to the condensing mirror, the table is provided with a moving mechanism for vertically moving the storage section. . A laser beam irradiation position observation device, characterized in that the transmission path between the reflecting mirror and the condensing mirror is expandable and retractable.