JPH02174278A - Monitor device for laser - Google Patents

Abstract

PURPOSE:To monitor airtightness of a laser container based on an easy, rapid and secure automatic operation of a gas leakage rate thereof by operating the gas leakage rate in a state of exhaust during oscillation pause, by storing it to a memory with backup battery, and by informing the leakage rate before laser oscillation is started. CONSTITUTION:When an input command of operation conditions is input from a keyboard 16 at a time T1, a microcomputer 14 inputs a signal of a detected pressure P1 from a pressure detector 10, and stores it to a memory 15 with backup battery together with a present time T1. Then, for example, at a time T2 in the next morning, when an operation command is input from the keyboard 16, an operation part of the microcomputer 14 reads the present time T2 and a present pressure P2. At the same time, it reads data P1, T1 which are stored in the memory 15 and acquires a leakage rate by operation. A leakage rate rhoi thus obtained is displayed in a CRT 17, and if it is not less than an allowable value, an alarm signal is output.

Description

DETAILED DESCRIPTION OF THE INVENTION [Object of the Invention] (Industrial Application Field) The present invention relates to a laser oscillator monitoring device useful for use in various laser oscillators.

(Prior Art) In a laser oscillator, it is necessary to sufficiently monitor the degree of sealing of the laser container.

For example, in a carbon dioxide laser oscillator used in laser processing machines, a container is filled with a mixed gas of carbon dioxide, nitrogen, and helium, and this gas is passed as a laser medium between electrodes arranged opposite each other. The mirrors are placed facing each other in a direction perpendicular to the arrangement direction, and the mirrors generate laser light and output an amplified laser beam.
If the container is not tightly sealed, gas pressure changes, mixing ratio changes, and impurity mixtures occur, resulting in problems such as unstable discharge (occurrence of arc discharge), internal corrosion, and laser instability.

Therefore, conventionally, when the laser emission is stopped, the filled gas is exhausted, and the leakage rate, that is, the proportion of air entering the container, is calculated between exhaustion and when the next operation starts, and compared with a predetermined tolerance value. The degree of sealing of the container was determined by this method.

(Problems to be Solved by the Invention) However, the conventional determination of the degree of sealing of a container has had problems in that calculations are time-consuming, calculations may be erroneous, and the determination tends to be made only on an ad hoc basis.

That is, in general, the leakage rate ρ [Torr/H] is calculated as follows: ρ-(P2- P+ )/(T2-T+) ・・
・It is calculated using (+>), but it takes time to calculate by using the operator's previous records and visually checking the current pressure, and errors in calculation may occur due to recording errors or errors in visually checking the pressure. Furthermore, if another operator operates the valve, calculations will no longer be possible.

Furthermore, the calculated leakage rate is usually used on an ad hoc basis and contains measurement errors depending on the measurement conditions, so it can be used to monitor the container itself beyond just the gas leakage rate. It is difficult to use it as a material for doing so.

According to the present invention, the gas leakage rate of the laser container can be easily, quickly, and reliably automatically calculated, and the sealing degree of the laser container and the laser oscillator can be monitored throughout the period. The purpose is to provide monitoring equipment.

[Structure of the Invention] (Means for Solving the Problems) A monitoring device for a laser beam oscillator of the present invention that solves the above problems detects the container pressure of the laser beam ff1B, as shown in FIG. a pressure detecting means 1 which inputs the detected pressure of the means 1 and a time signal from a clock 2, and a leak rate calculating means 3 which calculates a gas leak rate in an exhaust state when oscillation is stopped; A leakage rate recording means 5 records the leakage rate in a memory backed up by a backup power source 4, and notifies the leakage rate calculated this time before starting laser oscillation, and also records the leakage rate calculated in the past in an appropriate form as desired. It is characterized by comprising a notification means 6 for giving notification.

(Function) In the laser oscillator monitoring device of the present invention, the leakage rate in the exhaust state when oscillation is stopped is automatically calculated.

In addition, the automatically calculated leakage rate is reported before shooting, is recorded in a memory backed up by power supply, is graphed together with past leakage rates, is statistically processed, or is reported in an appropriate form.

(Example) Referring to FIG. 2, the carbon dioxide laser oscillator of this example is
A container 1 formed in the shape of a flat hollow cylinder is equipped with a blower 3 for generating a gas flow 2 of a mixture of carbon dioxide, nitrogen, and helium. A heat exchanger 4 for cooling the gas stream 2 passing therethrough is provided at the passage point of the gas stream p.

In the upper part of the container 1, a pair of positive and negative discharge electrodes 5.6 are provided above and below with respect to the gas flow 2. Further, a pair of folding mirrors 7.8 are disposed facing each other in the lateral direction of the gas flow 2, and a rear mirror 9 and half mirrors 10 are disposed on the sides of both folding mirrors 7.8, respectively.

Further, a pressure detector 10 is attached to one side of the container 1 to detect the pressure of the internal gas.

In the carbon dioxide laser oscillator having the above configuration, a laser medium sealed at a predetermined pressure is circulated in the container 1 by the blower 3, and the laser beam generated between the electrodes 5 and 6 is transmitted to each mirror 7 to
By reflecting the image for 10 minutes and causing co-pregnancy, a half mirror is created.
Laser light LB can be output from 10.

FIG. 3 is a block diagram of a control calculation device connected to the navigation laser oscillator.

As shown in the figure, a power supply circuit 11 that appropriately drives the blower 3, discharge north pole 5.6, and various valves is connected to a microcomputer 14 equipped with an internal clock via an input/output interface 12.13. ing.

A keyboard 17 and a CRT 18 are connected to the microcomputer 14 via a memory 15 backed up by power and an input/output interface 16 .

The microcomputer 14 inputs appropriate sensor signals such as laser output and temperature signals from the power supply circuit 11 and outputs appropriate control signals to the power supply circuit 11.
It monitors the laser oscillator, and in particular calculates the gas leakage rate shown below.

As shown in Fig. 4, the oscillation is now stopped at time To, the internal gas is exhausted at time To=T+, and the gas leakage rate is calculated at the next time T2, such as the next morning, to examine whether an abnormality has occurred. After that, it is assumed that gas is then filled and the next oscillation is started from time T3.

First, when a computation condition input command is input from the keyboard 16 at time T1, the microcomputer 14 inputs the signal of the detected pressure P1 from the pressure detector 10, and stores it in the power supply backup memory 15 together with the current time T+.

Next, for example, at time T2 the next morning, the keyboard 16
When a calculation command is inputted, the microcomputer 14
The calculation unit reads the current time T2 and the current pressure P2, and also reads the data P+ and T+ stored in the power supply backup memory 15, and calculates and obtains the leakage rate ρ of equation (1) shown in the conventional example.

The leakage rate ρi (i is the measurement number) thus obtained is:
It is displayed on the CRT 17, and if it is above the allowable value, an alarm signal is output.

Further, the calculated leakage rate ρi is stored in order in the power supply backup memory 15 together with the date and the operating status of the sensors read through the interface, and is displayed in a graph as appropriate based on an arbitrary display command from the keyboard 16. or displayed with diagnostic results as appropriate.

Therefore, the operator can display the leakage rate simply by inputting the calculation condition input command and the calculation command from the keyboard 16, and therefore can easily, quickly, and accurately know the leakage rate ρ.

In addition, if a pinhole occurs in the laser container 1 or a rare leak occurs in the valve, and this tends to gradually expand, this state can be expressed as a graph in which the leakage rate ρ1 gradually increases with the date. You can find it at

Furthermore, when the detection signals of various sensors are recorded, it is possible to monitor the laser container and, by extension, the laser oscillator, such as discovering defects in parts replaced when the leakage rate changes.

Furthermore, by storing the diagnostic program, it is possible to record the leakage rate ρ1 and the sensor signal and record the laser emission 1.
Increase the monitoring of eel equipment.

In the above embodiment, various commands are issued using the keyboard 16, but since the number of commands is small, a small number of switches may be used to issue the commands.

Further, in the above embodiment, the leakage rate is calculated at the exhaust end time T1 and the time T2 before the start of work in FIG. 4, but it may be automatically calculated at an intermediate time.

The present invention is not limited to the embodiments described above, and can be implemented in other forms of currency by making appropriate design changes.

[Effects of the Invention] As described above, since the present invention is a monitoring device for a laser oscillator as described in the claims, it is possible to automatically calculate the gas leakage rate of a laser container easily, quickly, and reliably. ,
The degree of opening of the laser vessel and thus the laser oscillator can be monitored over time.

[Brief explanation of the drawing]

Fig. 1 is a block diagram showing an overview of the present invention, Fig. 2 is a perspective explanatory diagram of a laser oscillator according to an embodiment of the invention, and Fig. 3 is a block diagram of a control calculation device connected to the laser oscillator of Fig. 2. FIG. 4 is a state diagram of gas pressure change. 1...Pressure detection means 2...Clock 3...Leak rate calculation means 4...Backup power source 5...Leak rate recording means 6...Notification means Agent Patent attorney Yasuo Miyoshi 1st Figure 3

Claims (1)

[Claims] a pressure detection means for detecting the container pressure of the laser oscillator; a leakage rate calculation means for inputting the detected pressure of the means and a time signal from a clock to calculate a gas leakage rate in an exhaust state when oscillation is stopped; A leakage rate recording means for recording the leakage rate in a memory backed up by a backup power supply, and a leakage rate recording means for notifying the leakage rate calculated this time before the start of laser oscillation, and recording the leakage rate calculated in the past in an appropriate form as desired. 1. A monitoring device for a laser oscillator, characterized in that it is equipped with a notification means for making a notification.