JPH04115582A - Laser - Google Patents

Abstract

PURPOSE:To make it possible to detect operational failures in an optical system by detecting the temperature of the optical system by means of a temperature sensor and determining if it is normal or abnormal based on the amount of variation of detected temperatures. CONSTITUTION:The temperature of a reflecting mirror 18 or a converging lens 19 is detected by each temperature sensor 21 and the detected temperature is converted into loss output by a loss output conversion device 22. The result is transmitted to a failure decision device 25 by way of an output setting device 23. The failure determination device 25 compares a loss output value stored in the early stage in a memory device 24 with the present output loss value. In the case when the present loss output value exceeds the early stage of loss output value by a fixed range, it determines that there is something wrong with the total reflecting mirror 18 or the converging mirror 19 and informs the need to inspect of the user by way of an announcing device 26. This construction makes it possible to detect the presence of operational failures in an optical system easily and protect the optical system from any possible damage.

Description

DETAILED DESCRIPTION OF THE INVENTION [Object of the Invention] (Industrial Application Field) The present invention relates to a laser device that emits laser light output from a laser oscillator through an optical system.

(Prior art) A typical example of this type of device is a laser processing device that uses laser light to cut or weld workpieces such as metal. An example of the conventional configuration of this processing device is shown in Figure 2. show. In the figure, a Laser oscillator 1 includes a resonator 2, a discharge power source 3, a control device 4, an optical sensor 5, and the like. Laser light 6 output from this laser oscillator 1
The light passes through the optical power bar 7, is reflected by a total reflection mirror 8 as an optical system, and the path is changed, and then is condensed by a condenser lens 9, also an optical system, and irradiates the workpiece 10. The workpiece 10 is processed by this laser beam 6. In this case, the total reflection mirror 8 and the condensing lens 9 are each provided with a temperature sensor 11, and these temperature sensors 1
The detected temperature of 1 is converted into a laser loss power by a loss power conversion device 12, and the output intensity of the laser beam 6 is set by an output setting device 13 taking this loss power value into consideration.Based on this setting, the control device 4 The output of the light 6 is controlled.

(Problem to be Solved by the Invention) In such a laser processing device, the total reflection mirror 9 and the condenser lens 10 have an increased light absorption rate due to aging such as dirt, and a decrease in light reflectance and light transmittance. However, the amount of heat generated increases accordingly.

If the amount of heat generated increases, there is a risk that the total reflection mirror 9 and the condenser lens 10 will deteriorate, resulting in poor processing accuracy or damage to them. However, since the conditions of the total reflection mirror 9 and the condenser lens 10 cannot generally be checked from the outside, it is conventionally necessary to remove and inspect the total reflection mirror 9 and the condenser lens 10 at regular intervals, for example. Ta. However, it is troublesome to remove and inspect the total reflection mirror 9 and the condenser lens 10 one by one, and there is also a risk of forgetting to inspect them and causing damage to them.

SUMMARY OF THE INVENTION Therefore, an object of the present invention is to provide a laser device that can detect abnormalities in an optical system on a product, clarify when to inspect the optical system, and prevent damage to the optical system. It is on offer.

[Configuration of the Invention (Means for Solving the Problems) In order to achieve the above object, the present invention provides a temperature sensor for detecting the temperature of the optical system, and also measures the amount of change in temperature detected by the temperature sensor. The optical system is characterized in that an abnormality detecting means for detecting an abnormality in the optical system is provided based on the optical system.

(Operation) The temperature of the optical system is detected by a temperature sensor, and based on the amount of change in the detected temperature, the abnormality detection means determines whether the optical system is normal or abnormal.

(Example) Hereinafter, an example in which the present invention is applied to a laser processing device will be described with reference to FIG.

The laser oscillator 11 includes a resonator 12, a discharge power source 13, a control device 14, a light sensor 15, and the like. The laser beam 16 outputted from the laser oscillator 11 passes through the optical power bar 17, is reflected by a total reflection mirror 18 as an optical system, and then has its path changed by a condenser lens 19, which also functions as an optical system. The light is focused on the workpiece 2
The workpiece 20 is irradiated with this laser beam 16.
processing is now being carried out.

Temperature sensors 21 for detecting these temperatures are attached to the total reflection mirror 18 and the condensing lens 19, respectively, and the detection results by these temperature sensors 21 are output to a loss output conversion device 22. Loss output conversion device 2
2 converts the temperature detected by the temperature sensor 21 into a loss output of the laser, and outputs the result to the output setting device 23 . The output setting device 23 sets the output intensity of the laser beam 16 by considering the loss output value from the loss output conversion device 22, outputs the result to the control device 14 of the laser oscillator 11, and also converts the loss output value into It is output to the storage device 24 and the abnormality determination device 25. Storage device 24 is initial (normal)
The abnormality determination device 25 compares the initial loss output value and the current loss output value, and determines whether the current loss output value is within a certain range with respect to the initial loss output value. If it is, it is determined to be normal, and if it is larger than a certain range, it is determined to be abnormal, and the user is notified, for example, via the notification device 26 that an inspection is required. Here, the loss output conversion device 22, the output setting device 23, the storage device 24, and the abnormality determination device 25 constitute an abnormality detection means 27.

In the above configuration, if the total reflection mirror 18 or the condenser lens 19 as an optical system becomes dirty or deteriorated, the amount of heat generated by them increases and the temperature rises. The temperature is detected by each temperature sensor 21, the detected temperature is converted into a loss output by a loss output conversion device 22, and the result is sent to an abnormality determination device 25 via an output setting device 23. The abnormality determination device 25 compares the initial (normal) loss output value stored in the storage device 24 with the current loss output value. If the current loss output value is larger than a certain range with respect to the initial loss output value in the abnormality determination device 25, it is determined that there is an abnormality in the total reflection mirror 18 or the condensing lens 19, and the notification device 25 The user is notified of the need for inspection through the system, and this notification makes it clear when to inspect the total reflection mirror 18 and the condensing lens 19.

Based on the notification, the user inspects the total reflection mirror 18 and the condensing lens 19, and depending on the results, cleans or replaces parts as necessary. As a result, the workpiece 20 is exposed to the workpiece 20 while the total reflection mirror 18 and the condensing lens 19 are deteriorated.
It is possible to prevent the total reflection mirror 18 and the condensing lens 19 from being damaged.

In the above embodiment, the temperature detected by the temperature sensor 21 is converted into a loss output value of the laser, and an abnormality in the optical system is detected based on a change in this loss output value. However, the temperature detected by the temperature sensor 21 is It may also be configured to detect an abnormality in the optical system based on the change itself. Further, the present invention is not limited to a processing device that processes a workpiece with laser light, but can also be applied to a device that simply emits laser light via an optical system.

[Effects of the Invention] As is clear from the above description, according to the present invention, in a laser device that emits laser light through an optical system,
This has excellent effects in that abnormalities in the optical system can be detected on the product, the timing for inspection of the optical system can be clarified, and damage to the optical system can be prevented.

[Brief explanation of the drawing]

FIG. 1 is a schematic configuration diagram showing an embodiment of the present invention, and FIG. 2 is a diagram corresponding to FIG. 1 showing a conventional configuration. In the drawing, 11 is a laser oscillator, 16 is a laser beam, 1
8 is a total reflection mirror (optical system), 19 is a condensing lens (optical system), 21 is a temperature sensor, and 27 is an abnormality detection means. Agent Patent Attorney Noriyuki Chika

Claims (1)

[Claims] 1. In a laser device that emits laser light output from a laser oscillator via an optical system, a temperature sensor detects the temperature of the optical system, and an abnormality in the optical system is detected based on the amount of change in temperature detected by this temperature sensor. A laser device characterized in that it is provided with an abnormality detection means for detecting an abnormality.