Laser device with heat transfer device for emitting heat from inside a housing to the outside

Abstract

Laser device (1), characterized in that the laser device a laser resonator (11) that oscillates laser light; a housing (6) that tightly seals a space in which the laser resonator is arranged; a temperature sensor (31) that detects the temperature of the air inside the housing; a humidity sensor (41) that detects the humidity of the air inside the housing; a heat transfer device (8) comprising a high-temperature section (23), a low-temperature section (22) arranged inside the housing in which the temperature is lower than that of the high-temperature section, and a cooling fan (13) which generates a flow of air in the low-temperature section and in which the heat from the low-temperature section moves to the high-temperature section; and a control device (7) comprising an operating control unit (71) which controls the cooling fan and a storage unit (72) which stores predefined information, comprising, wherein the storage unit stores a temperature reference value with respect to temperature and a humidity reference value with respect to humidity in order to control the cooling fan, wherein the operating control unit controls the cooling fan such that it is stopped in a dehumidification priority range in which the temperature detected by the temperature sensor is lower than the temperature reference value and the humidity detected by the humidity sensor is higher than the humidity reference value; the operating control unit controls the cooling fan such that it is driven at a maximum speed in a cooling priority range in which the temperature detected by the temperature sensor is higher than the temperature reference value and the humidity detected by the humidity sensor is lower than the humidity reference value; and the operating control unit controls the cooling fan such that it is driven at a predetermined average speed in a range (A, B) other than the dehumidification priority range and the cooling priority range.

Description

General state of the art 1. Field of invention

[0001] The present invention relates to a laser device which is provided with a heat transfer device for discharging heat from the inside of the housing to the outside. 2. Description of the state of the art

[0002] Inside the housing of a laser device are components including a laser resonator and a laser power source that supplies current to the laser resonator. Condensation can form on the components inside the housing. For example, the temperature inside the housing rises due to heat radiated by heat-generating components. Therefore, a cooling mechanism is provided to cool the components inside the housing. When hot air comes into contact with the area where the temperature has decreased due to cooling by the mechanism, condensation forms, producing water droplets. These water droplets can sometimes damage the components inside the laser device.

[0003] For example, in a laser device containing an optical fiber, condensation can damage the fiber. If water droplets adhere to the electrodes of a laser diode used as a light source, a short circuit can occur and the diode can be damaged. In a carbon dioxide laser, a high voltage is applied for laser oscillation. Therefore, if condensation occurs inside the laser device, sparks can be generated and the electrodes can be damaged. Furthermore, if water droplets adhere to components within the laser device, contamination or corrosion can occur, potentially damaging these components.

[0004] According to the prior art, a laser device is known in which the occurrence of condensation in the space inside the housing is predicted and the occurrence of condensation is prevented by controlling the supply of cooling water (see, for example, patent application JP 2016-219456 A). A laser device is also known in which the air inside the housing is dehumidified (see, for example, patent applications JP 2002-022332 A, JP 2008-141089 A, and JP H03-43739 A).

[0005] JP 2008-141089 A describes a device for housing electrical or electronic equipment, which can be arranged within a sealed enclosure. The interior of the enclosure is temperature and humidity controlled. Specifically, a cooling device with a Peltier element and two cooling fans is provided, enabling two-stage temperature control with simultaneous dehumidification. A temperature sensor and a humidity sensor are located within the enclosure to measure environmental variables. The Peltier element is positioned between the two cooling fans, with the first cooling fan containing the Peltier element located inside the enclosure and the second cooling fan located outside. Each cooling fan is connected to a heat sink in the direction of airflow and cools a fluid that circulates between the cooling fans to dissipate heat from the interior of the enclosure.Furthermore, a control system is provided that is connected to the sensors and controls the fans and the Peltier element.

[0006] Other devices are known, for example, from US 2015 / 0 159 888 A1, JP 2004-014886 A, WO 2013 / 042553 A1 and CN 102 778 908 A. Brief description of the invention

[0007] It is possible that a laser device may sound an alarm and stop operating if the humidity inside the housing is high, in order to prevent condensation. Furthermore, devices may be damaged if the temperature inside the housing becomes too high. Therefore, a laser device may sound an alarm and stop operating if the temperature inside the housing is high, in order to prevent damage to the device.

[0008] It is known to arrange a device for regulating humidity to prevent excessive humidity inside a laser device. This humidity-regulating device includes a low-temperature section where the temperature decreases, for example, by means of a Peltier element. The humidity-regulating device can reduce the humidity inside the housing by causing condensation to form in this low-temperature section.

[0009] On the other hand, when the humidity control device is operating, the air inside the housing is cooled because the temperature of the low-temperature section decreases. This means the humidity control device has both a humidity removal and a temperature-lowering function. Therefore, it is advantageous to control the device in such a way that humidity removal and air cooling are carried out efficiently.

[0010] Furthermore, in addition to the device for regulating temperature or humidity, a laser device may be equipped with a fan to circulate the air inside the housing, or a water discharge device to remove water formed by condensation. Such control is also advantageous for the fan and the water discharge device, as it allows for efficient regulation of the temperature or humidity inside the housing.

[0011] Therefore, it is advantageous if the laser device controls the devices contained within the laser device in such a way that the temperature and humidity of the space inside the housing are kept within a suitable range.

[0012] A laser device according to the present invention comprises a laser resonator that oscillates laser light and a housing that tightly seals a space in which the laser resonator is arranged. The laser device includes a temperature sensor that detects the temperature of the air inside the housing and a humidity sensor that detects the humidity of the air inside the housing. The laser device includes a heat transfer device comprising a high-temperature section, a low-temperature section arranged inside the housing in which the temperature is lower than that of the high-temperature section, and a cooling fan that generates a flow of air in the low-temperature section, thereby transferring heat from the low-temperature section to the high-temperature section.The laser device comprises a control unit that includes an operating control unit, which controls the cooling fan, and a memory unit, which stores predefined information. The memory unit stores a temperature reference value and a humidity reference value to control the cooling fan. The operating control unit controls the cooling fan such that it stops within a dehumidification priority range in which the temperature detected by the temperature sensor is lower than the temperature reference value and the humidity detected by the humidity sensor is higher than the humidity reference value.The operating control unit controls the cooling fan so that it runs at maximum speed within a cooling priority range where the temperature detected by the temperature sensor is higher than the temperature reference value and the humidity detected by the humidity sensor is lower than the humidity reference value. The operating control unit also controls the cooling fan so that it runs at a predefined average speed within a range other than the dehumidification priority range and the cooling priority range. Simple explanation of the drawings Fig. Figure 1 is a schematic view of a laser device according to embodiment 1. Fig. Figure 2 is an enlarged schematic view of a heat transfer device in the embodiment. Fig. Figure 3 is a block diagram of a control device in the embodiment. Fig. Figure 4 is a view that explains areas where control of the laser device is carried out. Fig. Figure 5 is a diagram that explains a second control of the laser device in embodiment 1. Fig. Figure 6 is a diagram that explains a third control of the laser device in embodiment 1. Fig. Figure 7 is a schematic view of a laser device according to embodiment 2. Fig. Figure 8 is a schematic view of a laser device according to embodiment 3. Fig. 9 is a schematic view of a laser device according to a non-inventive embodiment 4. Detailed explanation, version 1

[0013] With reference to Fig. 1 to Fig. Section 6 describes a laser device according to embodiment 1. In this embodiment, a fiber laser, which excites light through an optical fiber, is described as an example of the various types of laser devices.

[0014] Fig. Figure 1 shows the schematic structure of the laser device in the present embodiment. The laser device 1 comprises a laser resonator 11, which oscillates laser light. The laser resonator 11 of the present embodiment includes an optical fiber as the medium that amplifies the light. The laser device 1 is provided with a housing 6. The housing 6 has a tightly sealed structure to provide a tight seal for the space in which devices such as the laser resonator 11, etc., are arranged. For example, rubber sealing elements are arranged between the individual plate-shaped elements that form the housing 6. The tight seal of the housing 6 makes it possible to control the temperature and humidity of the space inside the housing 6.

[0015] The laser device 1 comprises a laser current source 12, which supplies current to the light source of the laser resonator 11.

[0016] In the present embodiment, a heat transfer device 8 and a stirring fan 14 are supplied with current from another power source. The laser device 1 includes the heat transfer device 8 to transfer heat from the air inside the housing 6 to the outside of the housing 6. The heat transfer device 8 of the present embodiment acts as a dehumidifier, removing moisture from the air inside the housing 6. It also acts as a cooler, cooling the air inside the housing 6. The heat transfer device 8 of the present embodiment is fixed to the housing 6. More precisely, the heat transfer device 8 of the present embodiment is arranged in an opening formed in the housing 6.

[0017] Fig. Figure 2 shows an enlarged schematic sectional view of the heat transfer device in the present embodiment. With reference to Fig. 1 and Fig. In the present embodiment, the heat transfer device 8 is an electronic cooler. The heat transfer device 8 includes a Peltier element 21. The Peltier element 21 comprises a low-temperature plate 21a, the temperature of which decreases upon application of current, and a high-temperature plate 21b, the temperature of which becomes higher than that of the low-temperature plate 21a. A thermoelectric semiconductor is arranged between the low-temperature plate 21a and the high-temperature plate 21b. By driving the Peltier element 21, heat is transferred from the low-temperature plate 21a to the high-temperature plate 21b by the action of the thermoelectric semiconductor.

[0018] A heat-radiating jacket 23, acting as a high-temperature section, is attached to the high-temperature plate 21b. The heat-radiating jacket 23 is located outside the housing 6. Cooling fins 22, acting as a low-temperature section with a lower temperature than that of the high-temperature section, are connected to the low-temperature plate 21a. The cooling fins are located inside the housing 6.

[0019] The heat-radiating jacket 23 is a heat exchanger cooled by cooling water. Cooling water lines 24 and 25, which supply cooling water, are connected to the heat-radiating jacket 23. Cooling water is supplied through cooling water line 24, as shown by arrow 91. A line carrying the cooling water runs through the interior of the heat-radiating jacket 23. The cooling water, which has undergone heat exchange inside the heat-radiating jacket 23, is discharged through cooling water line 25, as shown by arrow 92.

[0020] The heat transfer device 8 includes a cooling fan 13 to direct airflow through the cooling fins 22. The cooling fan 13 comprises an impeller 13b and a fan motor 13a, which rotates the impeller 13b. Driving the cooling fan 13 generates an airflow through the cooling fins 22, as indicated by arrow 93. Driving the Peltier element 21 transfers heat from the cooling fins 22 to the heat dissipation jacket 23. Consequently, the temperature of the cooling fins 22 decreases. Condensation of air on the surface of the cooling fins 22 dehumidifies the air inside the housing 6. The laser device 1 includes a water storage tank 61, which collects the water formed by condensation on the cooling fins 22. Water droplets adhering to the cooling fins 22 drip off and are collected in the water storage tank 61.The water droplets collected in the water storage tank 61 are expelled outside the housing 6.

[0021] Furthermore, an airflow can be generated by driving the cooling fan 13 inside the housing 6. Therefore, the cooling fan 13 also has the function of stirring the air inside the housing 6.

[0022] Since heat moves from the low-temperature section to the high-temperature section, the heat transfer device can employ any device capable of moving heat from inside the housing to the outside. For example, the heat transfer device can include a heat pump chiller with a compressor and an expansion valve. The heat-radiating jacket located outside the housing can be attached to the cooling fins located inside the housing. The cooling fins can then be cooled by supplying a cooling medium, the temperature of which has decreased, to the heat-radiating jacket. Furthermore, in the present embodiment, the high-temperature section is located outside the housing, but this configuration is not mandatory. The high-temperature section can also be located inside the housing. In this case, the high-temperature section can be cooled, for example, by cooling water.The cooling water that cooled the high-temperature section can be cooled by a heat exchanger or similar device located outside the housing. This means that the heat from the high-temperature section can be dissipated outside the housing via cooling water or similar means.

[0023] With reference to Fig. In this embodiment, the laser device 1 is equipped with a stirring fan 14 that stirs the air inside the housing 6. The stirring fan 14 comprises an impeller 14b and a fan motor 14a that rotates the impeller 14b. The stirring fan 14 is located inside the housing 6. It is positioned remotely from the heat transfer device 8. Furthermore, in this embodiment, the stirring fan 14 is larger than the cooling fan 13 of the heat transfer device 8. While this embodiment has one stirring fan 14 inside the housing, there is no limitation to this configuration, and multiple cooling fans can also be arranged inside the housing.

[0024] The laser device 1 comprises a control device 7. The control device 7 of the present embodiment is formed by a computing device (a computer) comprising a CPU (central processing unit) and RAM (random access memory), etc. The control device 7 controls the laser power source 12 and the laser resonator 11. Furthermore, the control device 7 controls the heat transfer device 8 and the stirring fan 14. In particular, the control device 7 controls the cooling fan 13 and the Peltier element 21 of the heat transfer device 8.

[0025] The laser device 1 comprises a first temperature sensor 31, which detects the temperature of the air inside the housing 6. The laser device 1 also comprises a first humidity sensor 41, which detects the humidity of the air inside the housing 6. The first temperature sensor 31 and the first humidity sensor 41 are arranged inside the housing 6. The control device 7 receives a signal regarding the temperature detected by the temperature sensor 31 and a signal regarding the humidity detected by the humidity sensor 41.

[0026] The components of the laser device 1, such as the heat transfer device 8, the laser resonator 11, the laser power source 12, and the stirring fan 14, etc., are arranged inside the housing 6. These components generate heat during operation. As a result, the temperature of the air inside the housing 6 increases. The control device 7 of the present embodiment is arranged outside the housing 6, but this arrangement is not mandatory. The control device 7 can also be arranged inside the housing 6.

[0027] Fig. Figure 3 shows a block diagram of the control device in the present embodiment. The control device 7 comprises an operating control unit 71, which sends operating commands to the devices contained in the laser device 1. The operating control unit 71 controls the laser power source 12 and the laser resonator 11. Furthermore, the operating control unit 71 controls the heat transfer device 8 and the stirring fan 14. The control device 7 includes a storage unit 72, which stores predefined information such as operating programs, reference values, and the like. The operating control unit 71 controls the respective devices based on the information stored in the storage unit 72. Additionally, the operating control unit 71 controls the respective devices based on the temperature detected by the first temperature sensor 31 and the humidity detected by the first humidity sensor 41.

[0028] Fig. Figure 4 shows a diagram explaining the areas for controlling the laser device in the present embodiment. For the laser device 1, an upper humidity limit for automatic shutdown of the laser device 1 is predefined. An upper temperature limit for automatic shutdown of the laser device 1 is also predefined. The upper humidity limit and the upper temperature limit are stored in the memory unit 72. The control device 7 obtains the humidity of the air inside the housing 6 from the humidity sensor 41. The control device 7 obtains the temperature of the air inside the housing 6 from the temperature sensor 31. The control device 7 compares the obtained temperature and humidity with the upper limits.If at least one of the conditions is that the humidity of the air inside the housing 6 has exceeded the upper limit, and the temperature of the air inside the housing 6 has exceeded the upper limit, the control device 7 takes such a control action that the laser device 1 is stopped. That is to say, the range in which the temperature of the air inside the housing 6 is at most the upper temperature limit and the humidity of the air inside the housing 6 is at most the upper humidity limit represents a range in which operation of the laser device 1 is possible.

[0029] In the present embodiment, a temperature reference value and a humidity reference value are predefined in order to control at least one of the cooling fan 13 of the heat transfer device 8 and the stirring fan 14. The temperature reference value and the humidity reference value are stored in the storage unit 72.

[0030] The humidity reference value is set below the humidity level at which there is a risk of damage to the devices contained in the laser device 1. For example, a humidity level is chosen that is lower than the level at which the electronic components contained in the devices are damaged. Furthermore, the humidity reference value is set below the upper humidity limit. Similarly, the temperature reference value is set below the temperature at which there is a risk of damage to the devices contained in the laser device 1. Furthermore, the temperature reference value is set below the upper temperature limit.

[0031] In the present embodiment, the operating range in which the temperature is lower than the temperature reference value and the humidity is at least at the humidity reference value is designated as the dehumidification priority range. The dehumidification priority range is a range in which the temperature is low and the humidity is high. This range is close to a humidity level at which the components contained in the laser device 1 would be damaged. Therefore, in the first control operation of the laser device 1, a control is implemented within the dehumidification priority range that prioritizes dehumidification of the air inside the housing 6 over cooling.

[0032] Furthermore, a region in which the temperature is at least at the upper temperature reference value and the humidity is lower than the humidity reference value is designated as the cooling priority region. The cooling priority region is a region in which the humidity is low and the temperature is high. This region is close to a temperature at which the devices contained in the laser device 1 would be damaged. Therefore, during initial control of the laser device 1 within the cooling priority region, a control is implemented that prioritizes cooling the air inside the housing 6 over dehumidification.

[0033] With reference to Fig. 1 to Fig. 4. The operating control unit 71 of the control device 7 obtains the temperature of the air inside the housing 6 from the temperature sensor 31. The operating control unit 71 also obtains the humidity of the air inside the housing 6 from the humidity sensor 41. The operating control unit 71 compares the temperature obtained from the temperature sensor 31 with the temperature reference value. Furthermore, the operating control unit 71 compares the humidity obtained from the humidity sensor 41 with the humidity reference value. If the temperature detected by the temperature sensor 31 is lower than the temperature reference value and the humidity detected by the humidity sensor 41 is at least equal to the humidity reference value, the operating control unit 71 takes such a control action that the cooling fan 13 of the heat transfer device 8 is stopped.

[0034] By driving the heat transfer device 8, the temperature of the cooling fins 22 decreases. By driving the cooling fan 13, air flows over the cooling fins 22 as shown by arrow 93, thus promoting heat exchange. By stopping the cooling fan 13, the continuous contact of the air inside the housing 6 with the cooling fins 22 can be prevented. Therefore, the temperature of the cooling fins 22 can be lowered further than when the cooling fan 13 is driven. Since condensation on the cooling fins 22 can be promoted, dehumidification of the air inside the housing 6 can also be promoted. Thus, when the condition of the air inside the housing 6 is in the dehumidification priority range, a control is implemented in which the cooling fan 13 is stopped and dehumidification is promoted.The operating control unit 71 can also promote dehumidification by reducing the rotational speed of the cooling fan 13.

[0035] If, on the other hand, the temperature detected by the temperature sensor 31 is at least equal to the temperature reference value and the humidity detected by the humidity sensor 41 is lower than the humidity reference value, the operating control unit 71 takes such a control action that the cooling fan 13 is driven. For example, the cooling fan 13 can be driven at its maximum speed. When the cooling fan 13 is driven, cooled air is returned to the interior of the housing 6, as shown by arrow 93. Therefore, the temperature inside the housing 6 decreases. In addition to its function of dehumidifying the air inside the housing 6, the heat transfer device 8 also has a function of cooling the air inside the housing 6. By driving the cooling fan 13, the air inside the housing 6 continuously strikes the cooling fins 22. Heat exchange can be promoted at the cooling fins 22.Thus, when the air inside the housing 6 falls within the cooling priority range, a control action is taken to drive the cooling fan 13 and promote cooling. Alternatively, when the cooling fan 13 is driven, cooling can also be promoted by increasing its rotational speed.

[0036] The laser device 1 of the present embodiment can automatically switch between the control mode that prioritizes cooling and the control mode that prioritizes dehumidification. The control device 7 can control the cooling fan 13 so that the temperature and humidity of the space inside the housing 6 remain within a suitable range. Therefore, damage to the components contained in the laser device 1 due to temperature or humidity can be prevented. Furthermore, the humidity inside the housing 6 can be prevented from reaching the upper humidity limit. Therefore, an automatic shutdown of the laser device 1 due to high humidity inside the housing 6 can be prevented. Additionally, the temperature inside the housing 6 can be prevented from reaching the upper temperature limit.Therefore, an automatic stopping of the laser device 1 due to a high temperature of the air inside the housing 6 can be suppressed.

[0037] With reference to Fig. 4. Any control configuration can be implemented in areas A and B other than the dehumidification priority area and the cooling priority area. For example, the same control configuration as in the dehumidification priority area or the same control configuration as in the cooling priority area can be selected in areas A and B. Alternatively, it is possible to implement the same control configuration as in the dehumidification priority area and the same control configuration as in the cooling priority area, switching between them at specific times. Furthermore, different control configurations than those in the dehumidification priority area and the cooling priority area can also be implemented in areas A and B.For example, in the first control described above, the cooling fan 13 is driven at maximum speed in the cooling priority area, while the cooling fan 13 is stopped in the dehumidification priority area. In contrast, the cooling fan 13 can be driven continuously at a predefined average speed in area A and area B.

[0038] Next, a second control mechanism for the laser device 1 in the present embodiment is explained. The second control mechanism is activated when the air inside the housing 6 is within the dehumidification priority range.

[0039] Fig. Figure 5 shows a diagram explaining the second control of the laser device in the present embodiment. The horizontal axis represents time, and the vertical axis represents the rotational speed (speed) of the cooling fan 13 of the heat transfer device 8. The second control involves changing the rotational speed of the cooling fan 13 at a predetermined interval when the air inside the housing falls within the dehumidification priority range. The operating control unit 71 stops the cooling fan 13 until time t1. At time t1, the operating control unit 71 drives the cooling fan 13 to its maximum rotational speed. After the cooling fan 13 has been driven for a predetermined time, it is stopped.At time t2, the operating control unit 71 issues a command to stop the cooling fan 13. The speed of the cooling fan 13 reaches zero. The cooling fan 13 then remains stationary for a specific period until time t3. From time t3 onwards, this control process is repeated. In the second control cycle, this same starting and stopping of the cooling fan 13 is performed repeatedly.

[0040] Water droplets formed by condensation adhere to the cooling fins 22. By repeatedly starting and stopping the cooling fan 13, the water adhering to the cooling fins 22 can be removed into the water storage tank 61. Condensation can then be encouraged to form again on the cooling fins 22.

[0041] The duration for which the cooling fan 13 is driven and the duration for which it is stopped can be set as desired. For example, the duration for which the cooling fan 13 is stopped (e.g., the time from time t2 to time t3) can be longer than the duration for which the cooling fan 13 is driven (e.g., the time from time t1 to time t2). It is advantageous if the duration for which the cooling fan 13 is stopped is not too long. For example, it is advantageous if the duration for which the cooling fan 13 is stopped is no longer than approximately 10 minutes. Furthermore, it is also possible to perform the second control at predetermined times during the period in which the first control described above is carried out and the cooling fan 13 is stopped.

[0042] In the present embodiment, the operating control unit 71 repeats the control in which the cooling fan 13 is driven, and the control in which the cooling fan 13 is driven. This control allows for large variations in the amount of air emitted by the cooling fan 13, ultimately causing water droplets adhering to the cooling fins 22 to drip off. However, the control in which the rotational speed is changed is not limited to this form; any method for changing the rotational speed can be used.

[0043] In this way, the operating control unit 71 can, when the temperature detected by the temperature sensor 31 is lower than the temperature reference value and the humidity detected by the humidity sensor is at least equal to the humidity reference value, perform a control action in which the rotational speed of the cooling fan 13 is changed at a predetermined interval. Conversely, the operating control unit 71 stops the control action in which the rotational speed is changed if the temperature detected by the temperature sensor 31 is at least equal to the temperature reference value. Furthermore, the operating control unit 71 stops the control action in which the rotational speed is changed if the humidity detected by the humidity sensor 41 is lower than the humidity threshold value.This means that the operating control unit 31 can stop the control, in which the rotational speed is changed at a predetermined period, in areas outside the dehumidification priority range. Since the other control functions are the same as the first control of the laser device 1, the explanation is not repeated here.

[0044] Next, a third control of the laser device 1 in the present embodiment is explained. In the third control, the operating control unit 71 controls at least one of the rotational directions of the stirring fan 14 and the rotational direction of the cooling fan 13.

[0045] First, the control of the rotation direction of the stirring fan 14 is explained. With reference to Fig. In the third control mode, the stirring fan 14 has the function of stirring the air inside the housing 6. When the state of the air inside the housing 6 is within the cooling priority range, the operating control unit 71 performs a control operation in which the direction of rotation of the impeller 14b of the stirring fan is changed at a predetermined interval.

[0046] Fig. Figure 6 shows a timing diagram of the third control stage of the laser device in the present embodiment. Up to time t1, the operating control unit 71 rotates the impeller 14b of the stirring fan 14 in one direction (clockwise). The operating control unit 71 detects that the air inside the housing 6 is in the cooling priority state. At time t1, the operating control unit 71 reverses the direction of rotation of the impeller 14b (counterclockwise). That is, the impeller 14b is rotated in the opposite direction so that the direction of airflow from the stirring fan 14 is reversed. After operation has continued for a predetermined time, the operating control unit 71 returns the direction of rotation of the impeller 14b to the first direction at time t2.In this way, the operating control unit 71 repeatedly performs a control cycle in which the impeller 14b is rotated in the forward direction and a control cycle in which the impeller is rotated in the opposite direction. In areas other than the cooling priority range, the operating control unit 71 stops the control cycle in which the direction of rotation of the impeller 14a is changed at a predetermined period.

[0047] By adjusting the control mechanism, which changes the direction of rotation of the impeller 14a, within the cooling priority range, the direction of the air blown by the stirring fan 14 can be periodically changed. Therefore, the air inside the housing 6 can be effectively stirred, and the cooling efficiency can be increased.

[0048] In the present embodiment, the operating control unit 71 repeats the control cycle in which the drive is performed at maximum speed in one direction, and the control cycle in which the drive is performed at maximum speed in the opposite direction. That is, the stirring fan 14 is driven at maximum speed during the driving cycle. By performing this control cycle, the amount of air blown by the stirring fan 14 can be increased, thus stirring the air inside the housing 6. The speed at which the stirring fan 14 is driven need not be its maximum speed. Furthermore, the control cycle in which the direction of rotation of the impeller 14b is changed at a predetermined interval can be performed continuously.Alternatively, the control, in which the direction of rotation of the impeller 14b is changed with a predetermined period, can also be carried out intermittently at predetermined time intervals.

[0049] The above explanation showed, by way of example, the control of the stirring fan 14, but the cooling fan 13 of the heat transfer device 8 also has the function of stirring the air inside the housing 6, as described above. The laser device 1 of the present embodiment comprises at least one fan that stirs the air inside the housing 6. The cooling fan 13 of the heat transfer device 8 and the stirring fan 14 can be shown as examples of the fan that stirs the air inside the housing 6. The same control as for the stirring fan 14 can also be implemented for the cooling fan 13. That is, the cooling fan 13 can also be controlled within the cooling priority range, whereby the direction of rotation of the impeller 13b is changed at a predetermined interval.

[0050] The operating control unit 71 can control the cooling fan 13 and the stirring fan 14 simultaneously. Or the operating control unit 71 can perform at least one control operation consisting of the control of the cooling fan 13 and the control of the stirring fan 14.

[0051] In this way, the operating control unit 71 can, during the third control, when the temperature detected by the temperature sensor 31 is at least the temperature reference value and the humidity detected by the humidity sensor 41 is lower than the humidity reference value, perform a control in which the direction of rotation of the impeller of at least one of the stirring fan 14 and the cooling fan 13 is changed with a predetermined period.

[0052] If at least one of the conditions is met—namely, that the temperature detected by temperature sensor 31 is lower than the temperature reference value, and the other being that the humidity detected by humidity sensor 41 is at least equal to the humidity reference value—the control system, which changes the direction of rotation of the impeller at a predetermined period, can be stopped. Since the other control functions are identical to those of the first control system of laser device 1, the explanation is not repeated here. Design 2

[0053] With reference to Fig. 7 describes a laser device according to embodiment 2. Fig. Figure 7 shows a schematic view of the laser device according to the present embodiment. The laser device 2 comprises a water discharge device 65, which discharges water collected in the water storage tank 61 (as a water storage section) outside the housing 6. In the present embodiment, the water discharge device 65 comprises a water discharge line 62 connected to the water storage tank 61 and a water discharge valve 63 arranged along the water discharge line 62. The control device 7 controls the water discharge device 65. The water discharge valve 63 is controlled by the operating control unit 71 of the control device 7.

[0054] The laser device 2 includes a storage water sensor 64, which detects the amount of water collected in the water storage tank 61. The storage water sensor 64 can be a sensor that detects water pressure, a sensor that detects water level, or the like. The signal indicating the amount of water detected by the storage water sensor 64 is sent to the control device 7.

[0055] The storage unit 72 of the control device 72 stores a temperature reference value with respect to the temperature, a humidity reference value with respect to the humidity, and a storage water quantity reference value with respect to the quantity of water collected in the water storage tank 61 in order to control the water discharge device 65. The temperature reference value and the humidity reference value for the laser device 2 of the present embodiment are the same as the temperature reference value and the humidity reference value for the laser device 1 of embodiment 1 (see Fig. 4) However, the temperature reference value and the humidity reference value are not limited to this form; any values ​​can be used to control the water discharge device. A storage water quantity reference value can be set such that the water does not overflow the water storage tank 61. That is, a value is applied that is less than the maximum storage capacity of the water storage tank 61.

[0056] With reference to Fig. 4 and Fig. The operating control unit 71 controls the water discharge device 65 when the air inside the housing 6 falls within the dehumidification priority range, so that the water from the water storage tank 61 is discharged at a predetermined interval. The operating control unit 71 performs a control function whereby the water is discharged periodically regardless of the amount of water in the water storage tank 61. The operating control unit 71 can discharge the water collected in the water storage tank 61 outside the housing 6 by opening the water discharge valve 63.In this way, the operating control unit 71 controls the water discharge device 65 when the temperature detected by the temperature sensor 31 is lower than the temperature reference value and the humidity detected by the humidity sensor 41 is at least equal to the humidity reference value, so that the water in the water storage tank 61 is discharged at a predetermined interval. For example, an operator can select a period during which only a small amount of water accumulates in the water storage tank 61.

[0057] The dehumidification priority area is an area where the humidity of the air inside the housing 6 is high. The operating control unit 71 can prevent a large amount of water from remaining in the water storage tank 61 by periodically ejecting the water. This prevents the water collected in the water storage tank 61 from evaporating and thus prevents the humidity from rising.

[0058] If, on the other hand, the state of the air inside the housing 6 is within the cooling priority range, the operating control unit 71 controls the water discharge device 65 so that the water storage tank 61 is emptied when the amount of water in the water storage tank 61 exceeds the storage water quantity reference value. That is, after the operating control unit 71 has waited for the amount of water in the water storage tank 61 to become large, it initiates a control action to open the water discharge valve 63. Thus, the operating control unit 71 detects that the temperature detected by the temperature sensor 31 is at least the temperature reference value and that the humidity detected by the humidity sensor 41 is lower than the humidity reference value.Then the operating control unit 71 controls the water discharge device 65 so that the water from the water storage tank 61 is discharged when the amount of water in the water storage tank 61 has exceeded the storage water quantity reference value.

[0059] When the amount of water in the water storage tank 61 becomes low, the water discharge line 62 may connect the inside of the housing 6 with the outside when the water discharge valve 63 is opened. Therefore, there is a risk that air from the outside of the housing 6 will enter the inside of the housing 6 and cause the temperature inside the housing 6 to rise. By implementing a control mechanism that opens the water discharge valve 63 when the amount of water in the water storage tank 61 exceeds the storage water quantity reference value, the ingress of air from the outside of the housing 6 into the inside of the housing 6 can be prevented. Consequently, a rise in the temperature of the air inside the housing 6 can be suppressed.

[0060] In the present embodiment, the water discharge device 65 comprises the water discharge line 62 and the water discharge valve 63, but there is no limitation to this form. The water discharge device can employ any configuration capable of discharging water collected in a water storage section outside the housing. For example, the housing can also include a door that opens and closes in conjunction with the water storage tank. Alternatively, the water discharge device can also include a pump that discharges the water collected in the water storage tank.

[0061] Since the further setup, effects and results of the laser device are the same as those of embodiment 1, the explanation is not repeated here. embodiment 3

[0062] With reference to Fig. Section 8 describes a laser device according to embodiment 3. Fig. Figure 8 shows a schematic view of the laser device according to the present embodiment. The laser device 3 according to the present embodiment comprises a cooling device that cools the devices arranged inside the housing 6. Here, the laser resonator 11 is explained as an example of the devices arranged inside the housing 6. The laser device 3 comprises a cooling water supply device 67 that supplies cooling water to the laser resonator 11. The cooling water supply device 67 delivers cooling water to the laser resonator 11 via a supply line 68, as shown by arrow 94. The cooling water returns to the cooling water supply device 67 via a return line 69, as shown by arrow 95. The cooling water supply device 67 is controlled by the operating control unit 71 of the control device 7.

[0063] The laser device 3 includes a cooling water temperature sensor 51, which detects the temperature of the cooling water supplied to the laser resonator 11. In the present embodiment, the cooling water temperature sensor 51 is arranged to detect the temperature of the water flowing in the supply line 68. The cooling water temperature sensor can also be arranged to detect the temperature of the water flowing in the return line.

[0064] The temperature of the components arranged in the laser resonator 11 depends on the temperature of the cooling water. This means that, as the temperature of the components decreases with decreasing cooling water temperature, condensation easily forms in the vicinity of the cooling water pipes. Furthermore, the lower the cooling water temperature, the more readily condensation forms in the vicinity of the cooling water pipes. Based on the air temperature inside the housing 6, detected by the first temperature sensor 31, and the cooling water temperature, detected by the cooling water temperature sensor 51, the operating control unit 71 can calculate the humidity level inside the housing 6 that causes condensation. The operating control unit 71 can define a lower humidity level than the level that causes condensation as a humidity reference value.For example, the operating control unit 71 can define a humidity reference value by subtracting a predefined tolerance value from the humidity that causes condensation. The storage unit 72 stores the defined humidity reference value. The control device 7 can then use this humidity reference value to perform the first and second control of the embodiments.

[0065] In the laser device 3 of the present embodiment, the humidity reference value can be set according to the actual temperature of the cooling water. The operating control unit 71 can set the humidity reference value lower as the temperature of the cooling water decreases. This control allows for the setting of an ideal humidity reference value. If the humidity reference value is set by an operator, it is necessary to set it with a large margin of error. Therefore, it can happen that the humidity reference value is set to a low value. In contrast, since the humidity reference value in the laser device 3 is set according to the actual temperature of the cooling water, the aforementioned margin of error can be made small. As a result, the dehumidification priority range is reduced, and the cooling priority range can be increased.

[0066] In the laser device 3 of the present embodiment, a control system can be implemented that prioritizes cooling and, in the event of a possibility of condensation, prioritizes dehumidification. That is, a control system can be implemented that prioritizes dehumidification only when there is a possibility of condensation. As a result, the air can be cooled effectively.

[0067] Since the further setup, effects and results of the laser device are the same as those of embodiments 1 and 2, the explanation is not repeated here. Design 4

[0068] With reference to Fig. 9 a laser device according to a non-inventive embodiment 4 is explained. Fig.Figure 9 shows a schematic view of the laser device according to the present embodiment. The laser device 4 of the present embodiment comprises at least one fan that stirs the air inside the housing 6. In the present embodiment, the cooling fan 13 and the stirring fan 14 have a function for cooling the air inside the housing 6. The laser device 4 comprises several temperature sensors 31, 32, 33 that detect the temperature of the air inside the housing 6, and several humidity sensors 41, 42, 43 that detect the humidity of the air inside the housing 6. That is, in addition to the first temperature sensor 31, the laser device 4 comprises a second temperature sensor 32 and a third temperature sensor 33. Furthermore, in addition to the first humidity sensor 41, the laser device 4 comprises a second humidity sensor 42 and a third humidity sensor 43.

[0069] The multiple temperature sensors 31, 32, 33 are arranged at widely separated positions inside the housing 6. Similarly, the multiple humidity sensors 41, 42, 43 are arranged at widely separated positions inside the housing. The temperature and humidity sensors are preferably arranged such that the distances between the temperature sensors or the distances between the humidity sensors are maximized.

[0070] It is possible that the temperature inside housing 6 will not be uniform, resulting in a temperature distribution. If the air temperature is not uniform, precise temperature-based control may not be possible. Alternatively, efficient air cooling may not be achieved.

[0071] In the first control of the laser device 4 of the present embodiment, the control device 7 detects the extent of the temperature distribution inside the housing 6. If the extent of the temperature distribution is large, the control device 7 performs a control action that promotes the stirring of the air inside the housing 6.

[0072] An operator defines a temperature distribution reference value for a variable relating to the temperature distribution inside the housing 6. The temperature distribution reference value is stored in the memory unit 72. The temperature distribution variable can be the difference between the highest and lowest values ​​of the multiple temperatures (Tmax - Tmin) detected by the multiple temperature sensors 31, 32, 33. Alternatively, the standard deviation of the multiple temperatures can be used as the temperature distribution variable.

[0073] The variable relating to the temperature distribution is not limited to this form. Any variable that determines the state of a temperature imbalance can be used as the variable relating to the temperature distribution. For example, one temperature sensor can be chosen from several to represent a standard. Then, the largest value among the differences between the temperature detected by this standard temperature sensor and the temperatures detected by the other temperature sensors can be used.

[0074] The operating control unit 71 of the control device 7 receives temperatures from the multiple temperature sensors 31, 32, 33. Based on the temperatures detected by the multiple temperature sensors 31, 32, 33, the operating control unit 71 calculates a variable relating to the temperature distribution. The operating control unit 71 compares this variable relating to the temperature distribution with the temperature distribution reference value. If the variable relating to the temperature distribution is at least equal to the temperature distribution reference value, it controls the operation of at least one of the stirring fan 14 and the cooling fan 13.

[0075] For example, the operating control unit 71 can drive both the stirring fan 14 and the cooling fan 13 when they are stopped. Alternatively, the operating control unit 71 can drive only one of the two fans when they are stopped. Or, the operating control unit 71 can drive the one fan from the stirring fan 14 and the cooling fan 13 that is stopped.

[0076] Alternatively, the operator can predefine an initial assessment value for the temperature distribution variable in addition to the temperature distribution reference value. This initial assessment value can be set to a higher value than the temperature distribution reference value. If the temperature distribution variable is greater than this initial assessment value, the operating control unit 71 can then drive both the stirring fan 14 and the cooling fan 13. Conversely, if the temperature distribution variable is at least equal to the temperature distribution reference value and less than the initial assessment value, the operating control unit 71 can control the operation by driving only one of the fans, a stirring fan 14 and a cooling fan 13.

[0077] The operating control unit 71 can then, if the variable relating to the temperature distribution is at least equal to the temperature distribution reference value, also perform a control in which the rotational speed of at least one of the stirring fan 14 and the cooling fan 13 is increased.

[0078] Next, if the variable relating to the temperature distribution is less than the temperature distribution reference value, the operating control unit 71 performs a control action in which at least one of the stirring fan 14 and the cooling fan 13 is stopped. For example, if the stirring fan 14 and the cooling fan 13 are driven, the operating control unit 71 can stop both the stirring fan 14 and the cooling fan 13. Or, if the stirring fan 14 and the cooling fan 13 are driven, the operating control unit 71 can stop only one of the fans. Or, the operating control unit 71 can stop the driven fan of the stirring fan 14 and the cooling fan 13.

[0079] Alternatively, the operator can predefine a second assessment value for the temperature distribution variable in addition to the temperature distribution reference value. This second temperature assessment value can be set to a lower value than the temperature distribution reference value. If the temperature distribution variable is lower than this second assessment value, the operating control unit 71 can then stop both the stirring fan 14 and the cooling fan 13. Conversely, if the temperature distribution variable is higher than both the second assessment value and lower than the temperature distribution reference value, the operating control unit 71 can control the operation by stopping only one of the fans, either the stirring fan 14 or the cooling fan 13.

[0080] The operating control unit 71 can then, if the variable relating to the temperature distribution is smaller than the temperature distribution reference value, also perform a control in which the rotational speed of only one of the stirring fan 14 and the cooling fan 13 is reduced.

[0081] In the first control system of the laser device of the present embodiment, the temperature of the air inside the housing 6 can be made uniform when the temperature distribution inside the housing 6 is high. Therefore, cooling can be carried out efficiently. When the temperature distribution inside the housing 6 is low, at least one of the stirring fan 14 and the cooling fan 13 can be stopped. This control system avoids unnecessary fan operation. That is, it aims to increase the efficiency of the fan operation.

[0082] In the laser device 4 of the present embodiment, humidity can also be controlled using the same method as for temperature control. It is possible that the humidity of the air inside the housing 6 will not be uniform, resulting in a humidity distribution. If the humidity is not uniform, precise humidity-based control may not be possible. Alternatively, efficient dehumidification of the air may not be achieved.

[0083] In the second control of the laser device 4 of the present embodiment, the control device 7 detects the extent of the moisture distribution inside the housing 6. If the extent of the moisture distribution is large, the control device 7 performs a control action that promotes the stirring of the air inside the housing 6.

[0084] An operator defines a humidity distribution reference value for a variable relating to the humidity distribution inside the housing 6. The humidity distribution reference value is stored in the memory unit 72. The difference between the highest and lowest values ​​of the multiple humidity levels (Hmax - Hmin) detected by the multiple humidity sensors 41, 42, 43 can be used as the humidity distribution variable. Alternatively, the standard deviation of the multiple humidity levels can be used as the humidity distribution variable.

[0085] The variable relating to humidity distribution is not limited to this form. Any variable that determines the state of humidity imbalance can be used as the variable relating to humidity distribution. For example, one humidity sensor can be chosen from several to represent a standard. Then, the largest value among the differences between the humidity detected by this standard humidity sensor and the humidity detected by the other humidity sensors can be used.

[0086] The operating control unit 71 of the control device 7 receives moisture readings from the multiple humidity sensors 41, 42, 43. Based on the multiple moisture readings detected by the humidity sensors 41, 42, 43, the operating control unit 71 calculates a variable relating to the humidity distribution. The operating control unit 71 compares this variable relating to the humidity distribution with the humidity distribution reference value. If the variable relating to the humidity distribution is at least equal to the humidity distribution reference value, it controls the operation of at least one of the stirring fan 14 and the cooling fan 13.

[0087] For example, the operating control unit 71 can drive both the stirring fan 14 and the cooling fan 13 when they are stopped. Alternatively, the operating control unit 71 can drive only one of the two fans when they are stopped. Or, the operating control unit 71 can drive the one fan from the stirring fan 14 and the cooling fan 13 that is stopped.

[0088] Alternatively, the operator can predefine an initial assessment value for the variable relating to humidity distribution, in addition to the humidity distribution reference value. This initial assessment value can be set to a higher value than the humidity distribution reference value. If the variable relating to humidity distribution is greater than this initial assessment value, the operating control unit 71 can then drive both the stirring fan 14 and the cooling fan 13. Conversely, if the variable relating to humidity distribution is at least equal to the humidity distribution reference value and less than the initial assessment value, the operating control unit 71 can control the operation in such a way that only one of the fans—the stirring fan 14 and the cooling fan 13—is driven.

[0089] The operating control unit 71 can then, if the variable relating to the moisture distribution is at least the moisture distribution reference value, also perform a control in which the rotational speed of at least one of the stirring fan 14 and the cooling fan 13 is increased.

[0090] Next, if the variable relating to the humidity distribution is less than the humidity distribution reference value, the operating control unit 71 performs a control action in which at least one of the stirring fan 14 and the cooling fan 13 is stopped. For example, if the stirring fan 14 and the cooling fan 13 are driven, the operating control unit 71 can stop both the stirring fan 14 and the cooling fan 13. Or, if the stirring fan 14 and the cooling fan 13 are driven, the operating control unit 71 can stop only one of the fans. Or, the operating control unit 71 can stop the driven fan of the stirring fan 14 and the cooling fan 13.

[0091] Alternatively, the operator can predefine a second assessment value for the humidity distribution variable in addition to the humidity distribution reference value. This second assessment value can be set to a lower value than the humidity distribution reference value. If the humidity distribution variable is lower than this second assessment value, the operating control unit 71 can then stop both the stirring fan 14 and the cooling fan 13. Conversely, if the humidity distribution variable is higher than both the second assessment value and lower than the humidity distribution reference value, the operating control unit 71 can control the operation by stopping only one of the fans, either the stirring fan 14 or the cooling fan 13.

[0092] The operating control unit 71 can then, if the variable relating to the moisture distribution is smaller than the moisture distribution reference value, also perform a control in which the rotational speed of only one of the stirring fan 14 and the cooling fan 13 is reduced.

[0093] In the second control system of the laser device of the present embodiment, the humidity of the air inside the housing 6 can be uniformly controlled when the humidity distribution inside the housing 6 is high. Therefore, dehumidification can be carried out efficiently. When the humidity distribution inside the housing 6 is low, at least one of the stirring fan 14 and the cooling fan 13 can be stopped. This control system avoids unnecessary fan operation. That is, it aims to increase the efficiency of the fan operation.

[0094] In this way, the temperature and humidity of the air inside the housing of the laser device 4 of the present embodiment can be kept uniform, while avoiding excessive fan operation. The laser device 4 can then perform precise control based on either temperature or humidity.

[0095] Since the further setup, effects and results of the laser device are the same as those of embodiments 1 to 3, the explanation is not repeated here.

[0096] The laser devices described in embodiments 1 to 4 above are fiber laser devices, but there is no restriction to this form; laser devices equipped with any laser resonator can be used. For example, a semiconductor laser having a laser diode as a light source, or a carbon dioxide laser equipped with a discharge tube into which carbon dioxide is introduced, or the like, can be used.

[0097] The laser device of one form of the present disclosure can control the devices contained in the laser device in such a way that the temperature and humidity of the air inside the housing are brought into a suitable range.

[0098] The embodiments described above can be combined in any way desired. In the individual drawings described above, identical or corresponding parts are designated with the same reference numerals. The embodiments described above are exemplary and do not limit the invention. Furthermore, embodiments also include modifications of the embodiments shown in the claims.

Claims

[1] Laser device (1), characterized by that the laser device a laser resonator (11) that oscillates laser light; a housing (6) that tightly seals a space in which the laser resonator is arranged; a temperature sensor (31) that detects the temperature of the air inside the housing; a humidity sensor (41) that detects the humidity of the air inside the housing; a heat transfer device (8) comprising a high-temperature section (23), a low-temperature section (22) arranged inside the housing in which the temperature is lower than that of the high-temperature section, and a cooling fan (13) which generates a flow of air in the low-temperature section and in which the heat from the low-temperature section moves to the high-temperature section; and a control device (7) comprising an operating control unit (71) which controls the cooling fan and a storage unit (72) which stores predefined information, comprising, wherein the storage unit stores a temperature reference value with respect to temperature and a humidity reference value with respect to humidity in order to control the cooling fan, wherein the operating control unit controls the cooling fan such that it is stopped in a dehumidification priority range in which the temperature detected by the temperature sensor is lower than the temperature reference value and the humidity detected by the humidity sensor is higher than the humidity reference value; the operating control unit controls the cooling fan such that it is driven at a maximum speed in a cooling priority range in which the temperature detected by the temperature sensor is higher than the temperature reference value and the humidity detected by the humidity sensor is lower than the humidity reference value; and the operating control unit controls the cooling fan such that it is driven at a predetermined average speed in a range (A, B) other than the dehumidification priority range and the cooling priority range. [2] Laser device (3) according to claim 1, comprising: a cooling water supply device (67) that supplies water for cooling the devices (11) arranged inside the housing; and a coolant temperature sensor (51) that detects the temperature of the coolant, wherein the operating control unit sets the humidity reference value based on the temperature of the air inside the housing detected by the temperature sensor and the temperature of the cooling water detected by the cooling water sensor, and The storage unit stores the defined humidity reference value.

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