JP3365813B2 - Laser processing equipment - Google Patents

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a laser processing apparatus using an optical fiber.

[0002]

2. Description of the Related Art A conventional laser processing apparatus using an optical fiber will be described with reference to FIG. A laser beam 2 is emitted from the laser oscillator 1. Laser light emitted 2
Passes through the light extractor 3 and then enters the optical fiber 5 from the fiber entrance lens 4. The laser light 2 incident on the optical fiber 5 is transmitted through the optical fiber 5, then exits from the optical fiber 5 and proceeds toward the light extractor 6. Then, the light passes through the light extractor 6, is condensed by the condenser lens 7, and is irradiated onto the workpiece 8.

The laser light 2 emitted from the laser oscillator 1 is partially reflected when passing through the light extractor 3 and is added to the detector 9 to detect the light intensity. In addition, even in the light extractor 6 located on the output side of the optical fiber 5, the laser light 2
Is partially reflected and the light intensity is detected by the detector 10.

The light intensities detected by the two detectors 9 and 10 are sent to, for example, an arithmetic control unit (not shown), the light intensities of both detectors 9 and 10 are calculated, and both are detected. Differences and ratios are required. Then, based on this calculation result, whether the laser light 2 is transmitted correctly or whether the laser light 2 is transmitted to the workpiece 8
It is determined whether or not is properly irradiated.

[0005]

In the case of the conventional laser processing apparatus, the light extractor 6 and the detector 1 are used to judge whether or not the laser light 2 is normally transmitted in the optical fiber 5.
0 is installed near the laser emitting portion on the output side of the optical fiber 5, for example, the condensing lens 7 that irradiates the workpiece 8 with laser light. Therefore, the presence of the light extractor 6 and the detector 10 makes the laser emitting portion larger by that amount.

By the way, a laser processing apparatus using an optical fiber is an apparatus that exhibits its characteristics particularly when the space for processing a workpiece is small, and it is desired that the laser emitting portion be as small as possible.

When the laser light 2 is transmitted to a long distance by using the optical fiber 5 and the remote portion is processed, the two detectors 9 and 10 are separated into the input side and the output side of the optical fiber 5. When it is located, for example, the detection signal of the one detector 10 on the output side of the optical fiber 5 must be transmitted to the arithmetic control unit on the input side of the optical fiber 5, and the detection signal of almost the same length as the optical fiber 5 is transmitted. A transmission cable is needed.

SUMMARY OF THE INVENTION It is an object of the present invention to solve the above-mentioned drawbacks, to provide a laser processing apparatus capable of reducing the size of a laser emitting portion and not requiring a long transmission cable.

[0009]

A laser processing apparatus of the present invention comprises a laser oscillator for emitting a laser beam, an optical fiber for transmitting the laser beam toward a workpiece, and the laser for transmitting the optical fiber. A condenser lens that irradiates the workpiece with light , a first detector that detects the intensity of laser light that travels in the optical fiber direction from the laser oscillator, and an optical path between the laser oscillator and the optical fiber. A second detector for detecting the intensity of the laser light reflected and returned from the optical fiber direction, and a calculation control unit for calculating the detection output of the first and second detectors.

Further, the laser processing apparatus of the present invention includes a laser oscillator for emitting a laser beam, an optical fiber for transmitting the laser beam toward a workpiece, and the laser beam transmitted through the optical fiber for processing. A condenser lens that illuminates objects,
Along the optical path between the laser oscillator and the optical fiber,
A second detector for detecting the intensity of the laser light reflected and returned from the optical fiber direction.

The second detector is composed of a plurality of detection elements, and the plurality of detection elements are arranged so as to form one surface.

[0012]

According to the present invention described above, a first detector for detecting laser light traveling from the laser oscillator in the optical fiber direction and a second detector for detecting laser light reflected back from the optical fiber direction. Are placed close to each other between the laser oscillator and the optical fiber. Thus two detectors
Since both are arranged close to the input side of the optical fiber, even when sending the detection signals of both detectors to the arithmetic control unit, for example, from the output side of the optical fiber to the input side of the optical fiber as before. It is not necessary to transmit the detection signal to the arithmetic control unit. Further, since it is not necessary to dispose a detector on the output side of the optical fiber, the laser emitting section for processing the workpiece can be made small.

Further, when the second detector is composed of a plurality of detecting elements, and the plurality of detecting elements are arranged so as to form one surface, they are reflected from the optical fiber direction. The two-dimensional distribution of the returning laser light can be detected, and the operating condition of each optical element can be grasped more accurately.

[0014]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENT An embodiment of the present invention will be described with reference to FIG. In FIG. 1, the same parts as those in FIG. 2 are designated by the same reference numerals.

Reference numeral 1 denotes a laser oscillator, and the laser oscillator 1
The laser light 2 emitted from is applied to the dielectric vapor deposition mirror 11. The dielectric vapor deposition mirror 11 is formed by stacking dielectric films in multiple layers, and the laser light 2 is almost totally reflected by the dielectric vapor deposition mirror 11. The laser beam 2 reflected by the dielectric vapor deposition mirror 11 is almost totally reflected by the other dielectric vapor deposition mirror 12, and is added to the fiber entrance lens 4. After that, by the fiber incidence lens 4,
It enters the optical fiber 5 and transmits in the optical fiber 5. The laser light 2 emitted from the optical fiber 5 is collected by the condenser lens 7
It is focused by and is irradiated to the work piece.

When the laser beam 2 emitted from the laser oscillator 1 is reflected by the dielectric vapor deposition mirror 11, a slight amount thereof passes through the dielectric vapor deposition mirror 11 and is detected as shown by the dotted line. Is added to the vessel 13. And the detector 1
At 3, the weak laser beam 2 transmitted through the dielectric vapor deposition mirror 11 is detected. The intensity of the light detected by the detector 13 is proportional to the intensity of the laser beam 2 emitted from the laser oscillator 1, and is used for managing the laser output of the laser oscillator 1 and the like.

When the laser light 2 is transmitted through the fiber entrance lens 4, the optical fiber 5, the condenser lens 7, etc.,
Part of the light is specularly reflected by the optical surface of each of these optical elements. The reflected laser light 2 returns in the opposite direction along the optical path of the laser light 2. Then, the returned laser beam 2 passes through the dielectric vapor deposition mirror 12 and is applied to the detector 14 as indicated by a dotted line to be detected. The light intensity detected by the detector 14 is proportional to the sum of the light reflected from each optical element. By monitoring the light intensity, abnormality of each optical element, such as damage or breakage, is detected. Can be detected.

The detection signals detected by the two detectors 13 and 14 are supplied to, for example, the arithmetic control unit 15. The arithmetic control unit 15 is provided integrally with the laser oscillator 1 or in the vicinity thereof, and arithmetically operates the detection signals of both detectors 13 and 14 to calculate the difference and ratio between the two. The calculation result is used for controlling the laser output and the like.

If a plurality of small detecting elements are used as the detector 14 and these detecting elements are arranged two-dimensionally so as to form one surface, the reflected light incident on the detector 14 will be described. The two-dimensional intensity distribution of can be detected. Using this detection result, it is possible to determine whether the laser light 2 is correctly incident perpendicularly to the fiber incident lens 4 or the optical fiber 5, and the change or the axis of the optical axis of the fiber incident lens 4 or the optical fiber 5 can be determined. You can see the degree of deviation.

Further, by calculating the detection signals of the two detectors 13 and 14 by the calculation control unit 15, the surface state of each optical element such as the fiber entrance lens 4, the optical fiber 5, the condenser lens 7 or the like, or The correctness of the optical axis of the laser light 2 incident on the optical fiber 5 can be comprehensively determined. Based on these judgments, for example, the laser oscillator 1 can be stopped, or an abnormal state can be visually displayed or can be notified by voice.

In the above embodiment, the light intensity detected by the one detector 14 is standardized by the light intensity detected by the other detector 13 and processed. Therefore, the calculation in the calculation controller 15 is not affected by the intensity of the laser beam 2 emitted from the laser oscillator 1.

[0022]

According to the present invention, since the detector is provided on the input side of the optical fiber and the transmission state of the laser light is detected by the reflected light from the optical element, the detector on the output side of the optical fiber is It becomes unnecessary and the laser emitting portion close to the workpiece can be made small. Also, since the two detectors can be placed close together, a long cable for transmitting the detector output is not required.

[Brief description of drawings]

FIG. 1 is a configuration diagram showing an embodiment of the present invention.

FIG. 2 is a configuration diagram illustrating a conventional device.

[Explanation of symbols]

1 ... Laser oscillator 2 ... laser light 4 ... Fiber incident lens 5 ... Optical fiber 7 ... Condensing lens 8 ... Workpiece 11, 12 ... Dielectric vapor deposition mirror 13, 14 ... Detector 15 ... Arithmetic control unit

Claims (3)

(57) [Claims] 1. A laser oscillator that emits laser light, and an optical fiber that transmits the laser light toward a workpiece.
A condenser lens for irradiating the workpiece with the laser light transmitted through the optical fiber, a first detector for detecting the intensity of the laser light traveling from the laser oscillator toward the optical fiber, the laser oscillator, and the Along the optical path between the optical fibers, the intensity of the laser light reflected back from the optical fiber direction.
A laser processing apparatus comprising: a second detector that detects a degree; and a calculation control unit that calculates detection outputs of the first and second detectors. 2. A laser oscillator that emits laser light, and an optical fiber that transmits the laser light toward a workpiece.
A condenser lens that irradiates the workpiece with the laser light transmitted through the optical fiber, and detects the intensity of the laser light reflected back from the optical fiber direction along the optical path between the laser oscillator and the optical fiber. A laser processing apparatus including a second detector that 3. The first detector according to claim 1, wherein the second detector is composed of a plurality of detecting elements, and the plurality of detecting elements are arranged so as to form a surface. The laser processing device described.