JPH0983044A - Cooler for laser oscillator - Google Patents

Abstract

PROBLEM TO BE SOLVED: To obtain a cooler for cooling the laser power supply section as well as a laser resonator while reducing the size of a laser oscillator and protecting the laser oscillator against damage due to dew formation. SOLUTION: Cooling water is fed from a cooling water supply 7 to a laser resonator 3 through a first supply pipe 9 and discharged through a first discharge pipe 11 while circulating thus cooling the laser medium, mirror, etc., in the laser resonator 3. In such a cooler for laser oscillator 1 the first supply pipe 9 and first discharge pipe 11 are coupled with a laser power supply section 5, respectively, through a second supply pipe 15 and a second discharge pipe 17. The cooler further comprises a mechanism for regulating the cooling water flow from the second supply pipe 15 to the laser power supply section 5 such that the temperature of a heating body at the laser power supply section 5 or at a part correlated therewith is kept within a specified range.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a laser oscillator cooling device for cooling a laser resonator and a laser power source power unit of a laser oscillator.

[0002]

2. Description of the Related Art Conventionally, for example, CO as a laser oscillator is used.
_{The two-} laser oscillator is excited by discharging the laser medium to obtain an optical output. The laser medium is heated to a high temperature, but the higher the temperature, the lower the oscillation efficiency. Therefore, the laser medium must be cooled as much as possible.

For this reason, a heat exchanger for water and a laser medium (gas) is generally provided to circulate a large amount of low-temperature water.
Since the oscillation efficiency of the laser medium increases as the temperature decreases, we want to lower the temperature of the cooling water as much as possible, but the laser oscillator has other parts that require cooling, such as mirrors that transmit and reflect laser light. Since these are in the atmosphere, if the temperature of the cooling water is too low, they will condense and damage the mirrors and the like. Therefore, in general, the temperature of the cooling water is set to 20 to 30 ° C. in many cases by setting the air temperature as a standard.

[0004]

By the way, recently, there has been a demand for downsizing of the apparatus, and the power source (high power, high voltage) for the above-described discharge is also water-cooled and downsized.
This is because semiconductor elements such as switching elements and diodes in the power supply are likely to reach a high temperature but are vulnerable to heat, and therefore need to be efficiently cooled.

In the case of air cooling, these elements are attached to a large radiator and a large cooling fan radiates heat. On the other hand, in the case of water cooling, it suffices to attach the element to a metal plate with a groove through which water flows and supply cooling water from the outside.
Significant miniaturization is possible. However, the inside of the power supply has a high voltage, and if water is present in the vicinity due to dew condensation, the electric circuit is short-circuited and damaged. Therefore, a dehumidifier or the like is used to prevent dew condensation, but there is a limit to the capacity, and a sensor is provided inside and power is turned off when dew condensation occurs.

An object of the present invention is to provide a cooling device for a laser oscillator, which realizes downsizing by cooling a laser resonator and a power source of a laser power source and prevents damage due to dew condensation. It is in.

[0007]

In order to achieve the above object, a cooling device for a laser oscillator according to the present invention according to claim 1 supplies cooling water from a cooling water supply device to a laser resonator through a first supply pipe. A cooling device for a laser oscillator, which cools a laser medium, a mirror, etc. in the laser resonator by discharging the gas through a first discharge pipe and circulating the second medium to the first supply pipe and the second discharge pipe, respectively. One end of the supply pipe and the second discharge pipe is connected, and a laser power source power unit is connected to the other end of the second supply pipe and the second discharge pipe. Flow controller for adjusting the flow rate of the cooling water flowing from the second supply pipe to the laser power source power unit so that the temperature of the place that changes in correlation with And it is characterized in that formed by providing a.

Therefore, the cooling water is supplied from the cooling water supply device to the laser resonator through the first supply pipe to cool the laser medium and the mirror. The cooling water used for cooling is returned from the laser resonator to the cooling water supply device through the first discharge pipe, and is then circulated again to cool the laser medium, the mirror, etc. one by one.

The cooling water flowing through the first supply pipe is sent to the laser power source power unit through the second supply pipe, and the heating element or a place changing in correlation with the heating element is cooled. The cooling water used for cooling is returned to the cooling water supply device through the second discharge pipe and the first discharge pipe, and is then circulated again to cool the heat generating element or a place changing in correlation with the heat generating element. It

The flow rate of the cooling water flowing from the second supply pipe is adjusted by the flow rate adjusting mechanism so that the temperature of the heating element in the laser power source power section or a place changing in correlation with the heating element is kept within a certain temperature range. Because it gets cooled
The laser oscillator can be downsized, and damage due to dew condensation can be prevented.

According to a second aspect of the present invention, there is provided a laser oscillator cooling device according to the first aspect, wherein the flow rate adjusting mechanism is provided in the middle of the second supply pipe. And a control unit for controlling the opening degree of the electric valve by increasing or decreasing the injection power.

Therefore, since the opening degree of the electric valve provided in the middle of the second supply pipe is adjusted by increasing or decreasing the injection power controlled by the control device, the heating element in the laser power source power section or this heating element The temperature of the place that changes in correlation is kept within a certain temperature range and cooled. Thus, the same effect as that of the first aspect can be obtained.

According to a third aspect of the present invention, there is provided a laser oscillator cooling apparatus according to the present invention, wherein the flow rate adjusting mechanism is provided in the middle of the second supply pipe, A temperature sensor that detects the temperature of the heating element in the laser power supply unit, and a control unit that controls the opening of the electric valve so that the temperature detected by the temperature sensor is maintained within a certain temperature range. It is characterized by that.

Therefore, the temperature of the heating element in the power source of the laser power source is detected by the temperature sensor. The control device is controlled based on the detected temperature of the heating element to adjust the opening degree of the electric valve provided in the middle of the second supply pipe. The temperature of the place that changes in correlation with the body is kept within a certain temperature range and cooled. Thus, the same effect as that of the first aspect can be obtained.

[0015]

BEST MODE FOR CARRYING OUT THE INVENTION Hereinafter, an example of an embodiment of the present invention will be described in detail with reference to the drawings.

Referring to FIG. 1, the laser oscillator 1 is composed of a laser resonator 3 and a laser power supply unit 5. A cooling water supply device 7 for cooling the laser medium, the mirror, etc. in the laser resonator 3 is provided. In this cooling water supply device 7, the temperature of the cooling water is set to 20 ° C., which is the same as the outside air temperature, for example.

The cooling water supply device 7 and the laser resonator 3 are connected by a first supply pipe 9 and a first discharge pipe 11. The electric valve 1 is provided in the middle of the first supply pipe 9.
3 are provided.

With the above structure, the cooling water cooled to, for example, 20 ° C. by the cooling water supply device 7 is supplied to the laser resonator 3 through the first supply pipe 9, and the laser medium and the mirror in the laser resonator 3 are supplied. Is cooled. The cooling water used for cooling is returned to the cooling water supply device 7 through the first discharge pipe 11, and the cooling water is circulated repeatedly again. The flow rate of the cooling water supplied to the laser resonator 3 is adjusted by adjusting the opening degree of the electric valve 13.

One end of a second supply pipe 15 is connected to the first supply pipe 9 near the laser resonator 3, and the other end of the second supply pipe 15 is connected to the laser power source power unit 5. ing. In addition, the first discharge pipe 11
Is connected to one end of the second discharge pipe 17, and the other end of the second discharge pipe 17 is connected to the laser power source power unit 5. Moreover, an electric valve 19 as a flow rate adjuster is provided in the middle of the second supply pipe 15.

With the above configuration, the cooling water supplied to the first supply pipe 9 is supplied to the laser power supply power unit 5 via the second supply pipe 15, and the high power and high voltage unit in the laser power supply power unit 5 is supplied. Is cooled. The cooling water used for this cooling flows through the second discharge pipe 17 to the first discharge pipe 11, and then is returned to the cooling water supply device 7, and the cooling water is repeatedly circulated again. The flow rate of the cooling water supplied to the laser power source power unit 5 is adjusted by adjusting the opening degree of the electric valve 19.

A laser power source control unit 21 for giving a power command to the laser power source power unit 5 to control the power, and a valve which is a part of a controller for giving a valve opening command to the electric valve 19 to control the flow rate. An opening degree command unit 23 is provided. The laser power source control unit 21 stores the relationship between the command and the output power as shown in FIG. Further, the valve opening command section 23 stores the relationship between the command and the valve opening as shown in FIG.

With the above configuration, when a command is given from the laser power supply control unit 21 to the laser power supply power unit 5, the laser power supply power unit 5 outputs the output power corresponding to the command as shown in FIG. To be done. Further, when a command is given from the laser power supply control unit 21 to the valve opening command unit 23, the valve opening command unit 23 commands the electric valve 19 with the valve opening corresponding to the command as shown in FIG. Is given. Therefore, the valve opening of the electric valve 19 is controlled, and the flow rate of the cooling water supplied from the second supply pipe 15 to the laser power source power unit 5 is adjusted.

For example, when the command is 0, the heat generation of the laser power source power unit 5 is 0 and cooling is not required. At this time, the cooling water is caused to flow, and if the ambient temperature is higher than the temperature of the cooling water, dew condensation occurs in the cooling unit, and if a command is input in the next stage, the laser power source power unit 5 is short-circuited and damaged. Therefore, when the command is 0, a command for opening the valve is given to the electric valve 19 so as not to flow the cooling water. When the power command is 0, the laser resonator 3 does not need to be cooled either, and thus the electric valve 13 may be opened and closed instead of the electric valve 19.

Since the heating element (eg, high power, high power section) of the laser power source power section 5 generates heat as the output power increases, a valve opening degree to such an extent that cooling water for cooling the heat generation can be flowed is pre-filed. Commands are issued in the relationship shown in FIG. As a result, the surroundings of the heating element will not always cool too much below the ambient temperature (ambient temperature) and will not condense.
The damage can be prevented and the laser oscillator 1 can be downsized.

FIG. 4 shows another example of the flow rate adjusting mechanism for adjusting the flow rate of the cooling water. In FIG. 4, a temperature sensor 25 is provided beside the heating element 5H in the laser power source power unit 5.
In order to keep the temperature detected by the temperature sensor 25 constant, a valve opening / closing command is issued to the electric valve 19 in comparison with a preset voltage corresponding to, for example, 30 ° C. to open / close the electric valve 19. May be controlled. Also in this case, the same effect as the above-described example can be obtained.

The present invention is not limited to the above-described embodiment, but can be embodied in other modes by making appropriate changes.

[0027]

As can be understood from the examples of the embodiment as described above, according to the first, second and third aspects of the invention, the flow rate of the cooling water flowing from the second supply pipe is a flow rate adjusting mechanism. Since the temperature of the heating element in the laser power source power section or the location that changes in correlation with this heating element is adjusted by opening and closing the valve and is kept within a certain temperature range and cooled,
The laser oscillator can be downsized and damage due to dew condensation can be prevented.

[Brief description of drawings]

FIG. 1 is an explanatory diagram illustrating a cooling device for a laser oscillator according to the present invention.

FIG. 2 is a diagram showing a relationship between a command and output power in a laser power supply controller.

FIG. 3 is a diagram showing a relationship between a command in a valve opening / closing command unit and a valve opening.

FIG. 4 is an explanatory view showing another example of a flow rate adjusting mechanism for adjusting the flow rate of cooling water.

[Explanation of symbols]

 1 Laser Oscillator 3 Laser Resonator 5 Laser Power Supply Unit 7 Cooling Water Supply Device 9 First Supply Pipe 11 First Drain Pipe 13 Electric Valve 15 Second Supply Pipe 17 Second Discharge Pipe 19 Electric Valve (Flow Control Mechanism) 21 Laser Power control unit 23 Valve opening command unit

Claims (3)

[Claims] 1. A cooling water supply device supplies cooling water to a laser resonator through a first supply pipe, and discharges and circulates the cooling water through a first discharge pipe so that a laser medium and a mirror in the laser resonator are discharged. A cooling device of a laser oscillator for cooling, wherein one ends of a second supply pipe and a second discharge pipe are respectively connected to the first supply pipe and the first discharge pipe, and the second supply pipe and the second discharge pipe are connected. A laser power source power unit is connected to the other end of the second power supply pipe so that the temperature of a heating element in the laser power source power section or a place changing in correlation with the heating element can be kept within a certain temperature range. A cooling device for a laser oscillator, comprising a flow rate adjusting mechanism for adjusting a flow rate of cooling water flowing to a laser power source power unit. 2. The flow rate adjusting mechanism includes an electric valve provided in the middle of the second supply pipe, and a control unit for controlling the opening degree of the electric valve by increasing or decreasing the injection power. The cooling device for a laser oscillator according to claim 1, wherein: 3. The flow rate adjusting mechanism, an electric valve provided in the middle of the second supply pipe, a temperature sensor for detecting the temperature of a heating element in the laser power source power section, and a temperature sensor for detecting the temperature. The cooling device for a laser oscillator according to claim 1, further comprising: a control unit that controls the opening degree of the electric valve so that the temperature is maintained within a certain temperature range.