JPS60221187A - Axial aligning device of laser beam and nozzle - Google Patents

Abstract

PURPOSE:To provide a titled device which speeds up axial alignment with high accuracy in irradiation of laser bean on a work coaxially with the hole of a nozzle for ejecting a gas by adjusting the position of the nozzle so that the pressure of the suction gas in a photodetecting member having the hole aligned to the optical axis of a laser is brought to the max. position. CONSTITUTION:A detector 9 for the pressure of the suction gas is operated after the hole 6 of the photodetecting member 8 is aligned to the optical axis of the laser light. The gas is fed 31 and is ejected from the hole 4 of the nozzle 3. The position of the nozzle 3 is finely adjusted to search and determine the position corresponding to the max. value of the detected 9 gaseous pressure. The optical axis is made coaxial with the hole 4 of the nozzle in this case, by which satisfactory laser machining is executed.

Description

[Detailed Description of the Invention] [Technical Field of the Invention] In particular, in a device that performs processing such as cutting, welding, and heat treatment on a workpiece by emitting a laser beam together with ejected gas from a nozzle, alignment of the nozzle and laser beam is particularly important. It is concerned with the ability to quickly and accurately perform operations.

[Prior art]

A conventional device of this type is shown in FIG. FIG. 1 is an explanatory diagram illustrating conventional alignment of a laser beam and a nozzle. In the figure, (11 is a condensing lens that condenses the laser beam, (2) is the condensed laser beam, (31 is a nozzle, and the laser beam + 21 t- is the light receiving member (5) along with the ejected gas. In this case, the acrylic The light is emitted to the plate. Note that (3a
) is the state where the nozzle is coaxial with the laser beam (21), (3b
) shows the state where the nozzle and the laser beam (21) are producing axillary silkworms. (31) is the supply port for the ejected gas, (4) is the ejected gas, for example Ar gas, and (61 is the laser beam on the acrylic plate (5). This is a hole made by irradiating light (2).

Next, the operation will be explained. When the acrylic plate (5) is irradiated with the laser beam (2) for a short time, the laser irradiation hole (6) is opened. At this time, for example, Ar gas (41
When the water is flushed, a gas ejection area (7) is formed on the surface of the acrylic plate (5). Now, if the nozzle (3) is coaxial with respect to the laser beam (2), that is, at the position (3a), the laser irradiation hole (6a) and the gas ejection area (7a) will be concentric circles on the acrylic plate (5). (Fig. 1(b)). However, if the lens or nozzle is replaced, the laser beam (
21 and the nozzle (3) are axially misaligned, for example, in the state shown in (3b), when the Ar gas (4) is ejected and the laser beam (2) is exhausted, the acrylic plate (5 )
A gas ejection region (7b) whose center is shifted from the laser irradiation hole (6b) is formed above (FIG. 1(C)). If laser cutting is performed in this state, the surface roughness of the cut surface will deteriorate and cutting may become impossible. In addition, welding defects occur in laser welding, which impairs performance, so the nozzle (3
1 in the front, back, left, and right directions using fine adjustment screws, etc., and then repeat the steps of laser irradiation and checking for traces to align the laser beam and the nozzle.

Conventional alignment of the laser beam and the nozzle is carried out as described above, so the amount of misalignment between the laser irradiation hole (6) and the gas ejection area (7) is visually determined9 and the nozzle (3) is aligned in the normal position direction. It has to be moved and adjusted, and because it is difficult to quantitatively grasp the amount of movement, there are drawbacks such as repeated visits to irradiate, visually inspect, adjust, and move.

[Summary of the invention]

This invention was made in order to eliminate the drawbacks of the conventional devices as described above, and includes a light-receiving member having a hole that coincides with the optical axis of the laser beam emitted from the nozzle, and a light-receiving member having a hole that corresponds to the optical axis of the laser beam emitted from the nozzle, and By providing a pressure detection device and adjusting the position of the nozzle so that the pressure reaches its maximum value, the laser beam and the nozzle are aligned quickly and with high precision.

[Embodiments of the invention]

An embodiment of the present invention will be described below with reference to the drawings. Second
The figure is a configuration diagram showing a laser beam and nozzle alignment device according to an embodiment of the present invention.

In the figure, (8) is a light-receiving member (
5) and for transmitting the pressure of the ejected gas (4) discharged through the hole (6) to the detection device (9);
It is a block with e. The detection device (9) consists of, for example, a pressure gauge or a pressure display device.

Next, the operation will be explained. When the laser beam (21) is irradiated on the acrylic plate (5) for a short time, a hole (6) is formed through it.
It's dark. The jetted gas (4) with pressure is sent there through the nozzle (
When the nozzle (3) is slightly moved back and forth and left and right while emitting light from the nozzle 3), the pressure distribution curve shown in FIG. 3 appears on the pressure gauge or pressure display device (9). FIG. 3 is a pressure distribution curve diagram of a detection device according to an embodiment of the present invention, and the horizontal axis shows the amount of movement when the nozzle (3) is slightly moved back and forth (or left and right). (6) and the nozzle (3a) are coaxial (position L), the maximum pressure value is displayed on the pressure display device (9). If the nozzle (31) shifts from this coaxial position to the front, back, left, or right, the pressure will drop and you will know that the nozzle (31) is not coaxial.
) by using a fine adjustment screw or the like, the laser beam and nozzle can be coaxially aligned more precisely and quickly, improving processing performance and quality of laser cutting, welding, etc. It also becomes possible to automate the alignment of the laser beam and the nozzle. In the above embodiment, an acrylic plate was used as the light receiving member (5) for drilling holes with the laser beam.

Other resins and metal plates may also be used. In addition, in the above explanation, in order to obtain a hole that coincides with the optical axis of the laser beam, the laser beam was irradiated on the all-acrylic plate to make the irradiation hole, but instead, a copper plate with fine holes was used and the hole was made to pass through the fine hole. The laser power may be measured using a power meter or the like on the back side, and the position where the maximum power is obtained is set as the laser optical axis, and the axis alignment may be performed by detecting the pressure of the ejected gas discharged through this pore in the same way as above. .

〔Effect of the invention〕

As described above, according to the present invention, there is a light-receiving member that passes through the laser beam emitted from the nozzle, and a sensor that detects the pressure of the ejected gas discharged through the hole. Since the device is equipped to adjust the position of the nozzle so that the pressure reaches its maximum value, it is possible to align the laser beam and the nozzle with high accuracy and speed.

[Brief explanation of the drawing]

FIG. 1 is an explanatory diagram illustrating conventional alignment of a laser beam and a nozzle, FIG. 2 is a configuration diagram showing a device for aligning a laser beam and a nozzle according to an embodiment of the present invention, and FIG. FIG. 3 is a pressure distribution curve diagram of a detection device according to an example. (2)... Laser light, +31... Nozzle, (4)...
・Blowout gas. (5)... Light receiving member, (6)... Hole, (9)...
In the detection device, the same reference numerals in the drawings indicate the same or corresponding parts. Agent: Masuo Oiwa No. 1 Figure 2 Figure 1 Figure 3 and 94 Procedures for Amendment (Voluntary) 1. Indication of the case: Japanese Patent Application No. 59-077792 2, Title of the invention: Laser beam and nozzle alignment device 3, Representative Hitoshi Katayama of the person making the amendment, Department 4, Representative drawing 6, Contents of the amendment No. J Figure No. Lurine Hyperactive No. L

Claims (1)

[Scope of Claims] (11) In a device in which a focused laser beam is emitted to a workpiece together with ejected gas through a nozzle coaxially adjusted with the laser beam, the light of the laser beam emitted from the nozzle. It is characterized by comprising a light receiving member having a hole aligned with the axis and a detection device for detecting the pressure of the ejected gas discharged through the hole, and adjusting the position of the nozzle so that the pressure shows a maximum value. (2) The hole aligned with the optical axis of the laser beam is formed by irradiating the light receiving member with the laser beam emitted from the nozzle. Laser beam and nozzle alignment device described in Section 1.