JP6484197B2 - Liquid temperature controller - Google Patents

Description

  The present invention relates to a liquid temperature control device that circulates a liquid by controlling the temperature of the liquid and supplying it to an object, adjusting the temperature of the liquid returned from the object again, supplying the liquid to the object.

As a liquid temperature control device, for example, a device for supplying cooling water to a laser processing machine is known (see Patent Document 1).
A laser processing machine is a device that performs processing such as drilling and cutting of a workpiece using laser light. Since the laser oscillator and the optical system of the laser processing machine are at high temperatures, it is necessary to always cool them during driving.

  The liquid temperature control apparatus shown in Patent Document 1 is provided so that two systems of cooling water can be supplied to the laser processing machine. This liquid temperature control device includes one tank for storing cooling water, a first circulation pump for sending cooling water from the tank to the laser processing machine, and a first cooling water path for circulating the cooling water using the first circulation pump. And a cooler for cooling the cooling water in the first cold water passage.

  In addition, the liquid temperature control device includes a second cold water path for circulating the cooling water of another system by the second circulation pump, and a cooler for cooling the cooling water in the second cold water path.

  The first cold water path is provided with an ion exchanger that makes the cooling water have a predetermined water quality (electrical conductivity) and a detector that detects whether the cooling water has reached the predetermined water quality.

The ion exchanger removes cations such as calcium, sodium, and magnesium in water and anions such as chlorine and carbonic acid with an ion exchange resin to generate pure water.
In general, an ion exchanger has an upper limit of the flow rate of water to be introduced. If a flow rate exceeding the upper limit is introduced, the removal of each ion becomes incomplete.

JP 10-335720 A

When an ion exchanger is provided to maintain the cooling water at a predetermined water quality as in the liquid temperature control apparatus of Patent Document 1, cooling water pumped by a circulation pump is introduced into the ion exchanger.
However, as described above, it is necessary to reduce the flow rate so that cooling water with a flow rate exceeding the upper limit is not fed into the ion exchanger.

  In order to reduce the flow rate to the ion exchanger, a valve that can adjust the opening degree may be provided. However, since it is necessary to control the opening and closing of the valve, a fine tube is arranged upstream of the ion exchanger. It is preferable to control the flow rate of the cooling water introduced to the ion exchanger through.

By the way, when it is detected that the cooling water has reached a predetermined water quality, it is not necessary to send the cooling water to the ion exchanger. Therefore, the introduction of the cooling water to the ion exchanger may be stopped, and in this case, the cooling water stays in the fine tube.
If the cooling water stays in the micropipe, the cooling water may freeze depending on the ambient temperature of the micropipe, and there is a problem that the micropipe may be damaged due to freezing.

  Accordingly, the present invention has been made to solve the above-described problems, and an object of the present invention is to provide a liquid temperature control device capable of preventing freezing of the liquid in the fine tube connected to the ion exchanger.

According to the liquid temperature control apparatus of the present invention, the tank for storing the cooling water, the supply pipe for circulating the cooling water from the tank to the object to be cooled, and the cooling water returned from the object to be cooled are circulated to the tank. A return pipe, a temperature controller for adjusting the temperature of the cooling water, an ion exchanger for removing ions from the cooling water, and a part of the cooling water is introduced into the ion exchanger by branching in the middle of the supply pipe An ion exchange circuit that introduces cooling water that has flowed out of the ion exchanger into the tank, a micropipe provided on the upstream side of the ion exchanger in the ion exchange circuit, the micropipe and the tank, or the tank And a freezing prevention mechanism for preventing freezing of the cooling water in the fine pipe by exchanging heat with the cooling water in the tank.
By adopting this configuration, even if the ambient temperature of the micropipe is low and the cooling water in the micropipe may freeze, it is possible to prevent the cooling water in the micropipe in the ion exchange circuit from freezing.

The anti-freezing mechanism may be configured by adhering the fine tube to an outer wall surface of the tank.
According to this configuration, heat exchange between the temperature of the outer wall surface of the tank based on the temperature of the cooling water in the tank and the fine pipe can prevent the cooling water in the fine pipe from freezing.

In addition, a heat insulating material covering the entire outer wall surface of the tank is provided, and the antifreezing mechanism is cut off so that a part of the heat insulating material is exposed to the outer wall surface of the tank according to the shape of the fine tube. The concave portion is formed, the fine tube is accommodated in the concave portion, and the surface of the concave portion in which the fine tube is accommodated is closed with another heat insulating material.
According to this configuration, when a heat insulating material is provided on the tank outer wall surface, heat is exchanged between the temperature of the tank outer wall surface based on the temperature of the cooling water in the tank and the fine pipe, and the heat insulating material By being cut off from the ambient temperature, the cooling water in the micropipe can be more reliably prevented from freezing.

The anti-freezing mechanism may be configured by immersing the fine tube in cooling water of the tank.
According to this configuration, freezing of the cooling water in the micropipe can be prevented by directly exchanging heat with the cooling water in the tank.

According to the liquid temperature control apparatus according to the present invention, the plurality of tanks for storing the cooling water, the plurality of supply pipes for circulating the cooling water from the respective tanks to the object to be cooled, and the cooling water returned from the object to be cooled A plurality of return pipes that circulate to each tank, a plurality of temperature controllers that regulate the temperature of the cooling water, and a cooling water that requires ion removal among the cooling water that circulates through each of the plurality of supply pipes One or more ion exchangers that remove ions and one or more supply pipes that circulate the cooling water that requires ion removal branch off in the middle to introduce a portion of the cooling water into the ion exchanger. One or more ion exchange circuits for introducing cooling water flowing out from the ion exchanger into each tank; and one or more fine tubes provided on the upstream side of the ion exchanger in each ion exchange circuit; Of each said tank, Cooling in the fine tube by exchanging heat with either a large tank or a tank with a high set temperature, or a cooling water in a tank with a large capacity or a cooling water in a tank with a high set temperature And one or a plurality of anti-freezing mechanisms for preventing water from freezing.
By adopting this configuration, in the liquid temperature control apparatus that can provide multiple systems of cooling water, by exchanging heat with a tank or cooling water having a large capacity or a high set temperature among the multiple tanks, Even if the ambient temperature is low and the cooling water in the micropipe may freeze, it is possible to prevent the cooling water in the micropipe in the ion exchange circuit from freezing.

The anti-freezing mechanism may be configured by adhering the fine pipe to an outer wall surface of either a tank having a large capacity or a tank having a high set temperature.
According to this configuration, heat exchange between the temperature of the outer wall surface of the tank based on the temperature of the cooling water in the tank and the fine pipe can prevent the cooling water in the fine pipe from freezing.

In addition, a heat insulating material that covers the entire outer wall surface of each tank is provided, and the anti-freezing mechanism includes a part of the heat insulating material that covers the outer wall surface of either a large capacity tank or a tank having a high set temperature. According to the shape of the fine tube, the outer wall surface of the tank is scraped off to form a concave portion, the fine tube is accommodated in the concave portion, and the surface of the concave portion in which the fine tube is accommodated is separated by another heat insulating material. It may be configured to be closed.
According to this configuration, when a heat insulating material is provided on the tank outer wall surface, heat is exchanged between the temperature of the tank outer wall surface based on the temperature of the cooling water in the tank and the fine pipe, and the heat insulating material By being cut off from the ambient temperature, the cooling water in the micropipe can be more reliably prevented from freezing.

The anti-freezing mechanism may be configured by immersing the fine tube in cooling water of a tank having a large capacity or a tank having a high set temperature.
According to this configuration, freezing of the cooling water in the micropipe can be prevented by directly exchanging heat with the cooling water in the tank.

  According to the present invention, it is possible to prevent freezing of the cooling water in the micropipe.

It is a block diagram which shows schematic structure of 1st Embodiment of a liquid temperature control apparatus. It is explanatory drawing which shows an example of a freeze prevention structure. In FIG. 2, it is explanatory drawing which shows the place which accommodated the loop-shaped part in the recessed part. In FIG. 3, it is explanatory drawing which shows the place which covered and closed the recessed part. It is a piping system diagram of a 1st embodiment. It is a piping system diagram of a 2nd embodiment. It is explanatory drawing which shows schematic structure of other embodiment.

(First embodiment)
Embodiments of a liquid temperature control device according to the present invention will be described below in detail with reference to the accompanying drawings.
FIG. 1 shows a schematic configuration of the liquid temperature control apparatus of the present embodiment and an object for supplying cooling water.
The liquid temperature control apparatus 20 of this embodiment supplies two systems of cooling water to the laser processing machine 10, and two systems of cooling water are a pure water system and a fresh water system.

The laser processing machine 10 that receives the supply of cooling water includes an oscillator 11 and an optical system 12 as devices that require the supply of cooling water.
The oscillator 11 is a device that oscillates laser light, and needs to be cooled in order to improve the stability of laser oscillation. The cooling water for cooling the oscillator 11 need not be pure water but may be fresh water.

  The optical system 12 includes a lens that outputs laser light and the like, and needs to be cooled to prevent heating. As cooling water for cooling the optical system 12, it is necessary to use pure water so that impurities in the cooling water do not adhere to the lens or the like.

  As described above, the liquid temperature control apparatus 20 of the present embodiment uses a first supply circuit 21 that supplies fresh water to the laser processing machine 10 to cool the oscillator 11 and a pure water laser to cool the optical system 12. And a second supply circuit 22 that supplies the processing machine 10.

The first supply circuit 21 includes a fresh water tank 24 that stores fresh water, a pump 26 that delivers fresh water from the fresh water tank 24, and a cooler 28 that adjusts the temperature of the supplied fresh water.
Further, the first supply circuit 21 includes a supply pipe 29 that supplies fresh water to the oscillator 11 of the laser processing machine 10 from the fresh water tank 24 through the pump 26 and the cooler 28, and the oscillator 11 of the laser processing machine 10. And a return pipe 31 for returning the fresh water toward the fresh water tank 24.

The second supply circuit 22 includes a pure water tank 30 that stores pure water, a pump 32 that feeds fresh water from the pure water tank 30, and a cooler 34 that adjusts the temperature of the pure water to be supplied (temperature referred to in the claims). ).
The second supply circuit 22 includes a supply pipe 35 that supplies pure water from the pure water tank 30 to the optical system 12 of the laser processing machine 10 via the pump 32 and the cooler 34, and the laser processing machine 10. And a return pipe 37 for returning pure water from the optical system 12 toward the pure water tank 30.

The supply pipe 35 on the downstream side of the pump 32 of the second supply circuit 22 is provided with a branch portion 36, and an ion exchange circuit 42 connected from the branch portion 36 to the ion exchanger 40 is provided.
The ion exchange circuit 42 is arranged so that a part of the pure water pumped by the pump 32 is introduced into the ion exchanger 40 and the pure water flowing out from the ion exchanger 40 is returned to the pure water tank 30.

The ion exchanger 40 has an ion exchange resin inside, and removes cations such as calcium, sodium and magnesium and anions such as chlorine and carbonic acid in water by the action of the ion exchange resin. Produce water.
In general, the ion exchanger 40 has an upper limit of the flow rate of water that can be introduced. If water is introduced into the ion exchanger 40 exceeding the upper limit of the flow rate, the production capacity of pure water is reduced, so that it is necessary to control the amount of water introduced into the ion exchanger 40. The upper limit of the flow rate introduced into the ion exchanger 40 varies depending on the capacity of the pure water tank 30, but in this embodiment, the capacity of the pure water tank 30 is 9 liters. The thing of about liter / min is adopted.

  Therefore, the amount of water introduced into the ion exchanger 40 is controlled by using a fine tube 44 in the ion exchange circuit 42 on the inlet side of the ion exchanger 40 from the branch portion 36 in the ion exchange circuit 42. Furthermore, in order to ensure the length of the fine tube 44, a loop-shaped portion 44a wound in a loop shape in the middle portion is formed.

A nylon tube is adopted as the fine tube 44 of the present embodiment. The nylon tube of the present embodiment has a total length of 2 m and an inner diameter of 2.5 mm, but the length and inner diameter may be appropriately set according to the flow rate introduced into the ion exchanger 40.
The fine tube 44 is not limited to a nylon tube, and may be made of other materials such as metal.

The liquid temperature control device 20 includes an anti-freezing mechanism that prevents the cooling water in the fine pipe 44 from being frozen by exchanging heat between the fine pipe 44 and the tank or the cooling water in the tank.
In this embodiment, the capacity of the pure water tank is 9 liters, the capacity of the fresh water tank 24 is 90 liters, and the capacity of the fresh water tank 24 is larger than that of the pure water tank 30. The structure which performs heat exchange with is adopted.
Specifically, the loop-shaped portion 44 a of the fine pipe 44 is attached to the outer wall surface of the fresh water tank 24, and heat is exchanged between the loop-shaped portion 44 a and the outer wall surface of the fresh water tank 24 to cool the inside of the fine pipe 44. We are trying to prevent water from freezing.
However, the loop-shaped portion 44a of the fine tube 44 may be attached not by a tank having a large capacity but by a tank having a higher set temperature.

A method of attaching the fine pipe 44 to the fresh water tank 24 (but not limited to fresh water as a tank) will be described with reference to FIGS.
First, the outer wall surface of the fresh water tank 24 is covered with the heat insulating material 14. The reason why the outer periphery of the tank is covered with the heat insulating material 14 is to prevent temperature change of the fresh water in the fresh water tank 24.

  As shown in FIG. 2, the heat insulating material 14 is formed with a recess 15 that is cut out in a shape that matches the size of the loop-shaped portion 44 a of the fine tube 44 and exposes the tank outer wall surface.

  As shown in FIG. 3, the loop-shaped portion 44 a of the fine tube 44 is accommodated in the recess 15 formed in the heat insulating material 14. At this time, the loop-shaped portion 44a is stored so as to be surely brought into contact with the tank outer wall surface. Further, the loop-shaped portion 44a may be attached to the tank outer wall surface with an adhesive tape or the like so that the loop-shaped portion 44a can be kept in contact with the tank outer wall surface.

As shown in FIG. 4, after accommodating the loop-shaped part 44a in the recessed part 15, the lid | cover 16 which covers the loop-shaped part 44a is affixed on the loop-shaped part 44a. Affixing the lid 16 further contributes to prevention of freezing of the loop-shaped portion 44a in the recess 15.
As the lid 16, it is preferable to use a cutout piece of a heat insulating material when the concave portion 15 is cut out because the size of the concave portion 15 matches.

Further, if a hole 17 that can penetrate the fine tube 44 is formed in the lid 16, the fine tube 44 can be taken out from the recess 15 through the hole 17. Without generating a gap, the temperature of the loop-shaped portion 44a can be maintained at the same level as the temperature of the tank outer wall surface.
3 and 4, only one hole 17 is shown, but two holes 17 may be formed.

FIG. 5 shows a piping system diagram of the present embodiment, and a more specific configuration of the liquid temperature control apparatus of the present embodiment will be described. The piping system diagram of FIG. 5 is different from the schematic configuration shown in FIG. 1 in the arrangement of the cooler and the like, but two systems of pure water and fresh water are supplied to the laser processing machine 10. It is the same embodiment as a liquid temperature control device to be supplied.
In addition, the same code | symbol is attached | subjected about the component same as the component demonstrated in FIG. 1, and description may be abbreviate | omitted.

First, the fresh water supply system will be described.
The liquid temperature control device 20 is provided with a supply pipe 29 for supplying fresh water from the fresh water tank 24 to the oscillator, and a return pipe 31 for returning the fresh water from the oscillator to the fresh water tank 24.
A pump 26 is disposed above the fresh water tank 24. The fresh water in the fresh water tank 24 is introduced into the cooler 28 by driving the pump 26. In addition, although the cooler 28 shown here is arrange | positioned inside the fresh water tank 24, the arrangement | positioning position of the cooler 28 may be the exterior of the fresh water tank 24. FIG.

A supply sensor 29 extending from the cooler 28 is provided with a temperature sensor 50 and a pressure sensor 51. A valve 52 is provided at the outlet side end of the supply pipe 29.
A valve 57 is provided at the inlet side end of the return pipe 31 from the oscillator.

A bypass pipe 54 communicating with the fresh water tank 24 is connected between the pressure sensor 51 of the supply pipe 29 and the valve 52. A bypass valve 55 is provided in the middle of the bypass pipe 54 to open and close the bypass pipe 54.
By providing the bypass pipe 54, when the pressure of the fresh water supplied to the oscillator is high, the fresh water supplied from the bypass pipe 54 to the fresh water tank 24 can be reduced.

  A water supply pipe 58 for water supply is connected to the fresh water tank 24. A ball tap 60 and a valve 61 interlocking with the ball tap 60 are provided at the tip of the water supply pipe 58 in the fresh water tank 24. If the water supply pipe 58 is connected so that fresh water can be introduced from the outside, the operation of the ball tap 60 and the valve 61 can always keep the inside of the fresh water tank 24 at a predetermined water level.

  The fresh water tank 24 is provided with an overflow exhaust pipe 62 and a drain exhaust pipe 87. The overflow discharge pipe 62 is provided to drain the excess amount of fresh water when the water level of the fresh water tank 24 exceeds a predetermined position.

  Further, a liquid level gauge 63 and a float switch 64 are provided in the fresh water tank 24. The liquid level gauge 63 is provided for confirming the amount of fresh water stored in the fresh water tank 24. When the float switch 64 detects that the amount of fresh water in the fresh water tank 24 is less than a predetermined amount, the float switch 64 operates to stop driving the pump 26.

Next, temperature adjustment of fresh water will be described.
The cooler 28 is a heat exchanger that exchanges heat between the refrigerant circulating in the refrigeration circuit 70 and the fresh water pumped out of the fresh water tank 24 by the pump 26 using an evaporator in the refrigeration circuit 70.

  The refrigeration circuit 70 includes a compressor 72 and a branching portion 77 that branches the high-temperature refrigerant compressed by the compressor 72 into a first channel 78 and a second channel 79. In the first flow path 78, a pressure sensor 80, a condenser 84 having a fan 82, a strainer 85, and an expansion valve 75 are provided. An expansion valve 76 is provided in the second flow path 79.

The high-temperature and high-pressure refrigerant in the first flow path 78 is condensed by the condenser 84 and further becomes low-temperature and low-pressure by the expansion valve 75. The high-temperature and high-pressure refrigerant in the second flow path 79 becomes low pressure by the expansion valve 76 and merges with the refrigerant that has passed through the first flow path 78 on the inlet side of the cooler 28.
The combined refrigerant cools fresh water to a predetermined temperature in the cooler 28, passes through the accumulator 86, and returns to the compressor 72.

  A heater 88 is provided in the fresh water tank 24. When it is desired to raise the fresh water temperature in the fresh water tank 24, the fresh water temperature can be easily raised by turning on the heater 88.

Next, the pure water supply system will be described.
A supply pipe 35 for supplying pure water from the pure water tank 30 to the optical system and a return pipe 37 for returning pure water from the optical system to the pure water tank 30 are provided.
A pump 32 is disposed on the pure water tank 30. The pure water in the pure water tank 30 is supplied to the supply pipe 35 by driving the pump 32. A valve 90 is provided at the outlet side end of the supply pipe 35.

  A valve 91 is provided at the inlet side end of the return pipe 37 from the optical system. A cooler 34 that adjusts the temperature of pure water before being returned to the pure water tank 30 is provided in the middle of the return pipe 37. The cooler 34 introduces fresh water cooled to a predetermined temperature from the fresh water supply pipe 29, and cools the pure water returned from the optical system by exchanging heat with the fresh water.

That is, the cooler 34 branches from the fresh water supply pipe 29 into the fresh water supply pipe 95 having the constant flow valve 92 and the valve 94, and the fresh water whose temperature has risen through the cooler 34 to the fresh water return pipe 31. A fresh water return pipe 96 is provided.
Thus, by cooling pure water with fresh water, it is not necessary to provide an extra refrigeration cycle circuit, and cost reduction and space saving can be achieved.

However, the temperature adjustment of pure water is not limited to such a configuration, and the temperature may be adjusted using a refrigeration cycle circuit.
The cooler 34 may be provided in the pure water supply pipe 35 instead of being provided in the pure water return pipe 37.

  A temperature sensor 98 is provided in the pure water supply pipe 35. The temperature of pure water in the cooler 34 can be controlled by controlling the valve 94 of the fresh water supply pipe 95 based on the temperature detected by the temperature sensor 98.

  A heater 108 is provided in the pure water tank 30. When the pure water temperature in the pure water tank 30 is desired to be raised, the pure water temperature can be easily raised by turning on the heater 108.

A bypass pipe 100 communicating with each other is connected between the supply pipe 35 and the return pipe 37. A bypass valve 102 is provided in the middle of the bypass pipe 100 to open and close the bypass pipe 100.
By providing the bypass pipe 100, when the pressure of pure water supplied to the optical system is high, the pressure of pure water supplied to the optical system can be lowered by returning pure water from the bypass pipe 100 to the return pipe 37. .

A water supply pipe 104 and a drain pipe 105 are connected to the pure water tank 30.
The pure water tank 30 is provided with an overflow exhaust pipe 106. The overflow drain pipe 106 is provided for draining the excess fresh water when the water level of the pure water tank 30 exceeds a predetermined position.

  Further, the pure water tank 30 is provided with a liquid level gauge 109 and a float switch 110. The liquid level gauge 109 is provided for confirming the amount of pure water stored in the pure water tank 30. When the float switch 110 detects that the amount of pure water in the pure water tank 30 has become less than a predetermined amount, the float switch 110 operates to stop driving the pump 32.

An electrical conductivity sensor 112 is provided in the pure water tank 30, and an electrical conductivity meter 114 connected to the electrical conductivity sensor 112 is provided outside the pure water tank 30.
By checking the electric conductivity meter 114, the purity of pure water can be controlled.

A branch portion 36 is provided in the middle of the supply pipe 35, and an ion exchange circuit 42 is provided that branches from the branch portion 36. The ion exchange circuit 42 is provided with a valve 120 for turning on / off the introduction of pure water into the ion exchanger 40.
That is, when the electric conductivity meter 114 determines that the purity of the pure water in the pure water tank 30 is sufficient, the valve 120 is closed and the introduction of pure water into the ion exchanger 40 is stopped. Can do.

  The ion exchange circuit 42 employs a normal pipe line from the branch portion 36 to the valve 120, and employs a fine tube 44 from the valve 120 to the ion exchanger 40. A loop-shaped portion 44 a is formed in the middle of the fine tube 44 by winding the fine tube 44 into a loop shape.

The loop-shaped portion 44a is attached to the outer wall surface of the fresh water tank 24 having a capacity larger than that of the pure water tank 30 to prevent freezing.
As a method for attaching the loop-shaped portion 44a to the fresh water tank 24, the method shown in FIGS. However, when the fresh water tank 24 is not provided with a heat insulating material, the loop portion 44a may be simply attached to the outer wall surface of the tank with an adhesive tape or the like.

Such a structure for preventing freezing of the micropipe 44 of the ion exchange circuit 42 is effective particularly when the introduction of pure water into the ion exchanger 40 is stopped.
That is, when the purity of pure water detected by the electrical conductivity sensor 112 is sufficient, it is not necessary to introduce pure water into the ion exchanger 40, and the valve 120 is closed to stop the introduction of pure water. At this time, pure water remains in the fine tube 44 as it is. The liquid temperature control device 20 may be installed at a low temperature, and the pure water remaining in the fine tube 44 may be frozen. Therefore, by adopting such a freeze prevention structure, it is possible to prevent the pure water in the micropipe 44 of the ion exchange circuit 42 from freezing.

(Second Embodiment)
FIG. 6 shows a piping system diagram of the second embodiment of the liquid temperature control device.
The second embodiment is the same as the first embodiment in that two systems of cooling water can be supplied. While the first embodiment has two systems of fresh water and pure water, the second embodiment differs from the first embodiment in that two systems of pure water are supplied.
Note that the same components as those described in the first embodiment are denoted by the same reference numerals, description thereof is omitted, and only differences are described.

  The liquid temperature control apparatus 200 according to the present embodiment supplies cooling water to the laser processing machine 10 (see FIG. 1), and supplies pure water to both the oscillator 11 and the optical system 12.

A circuit for supplying pure water to the oscillator 11 will be described.
Pure water supplied to the oscillator 11 is stored in the first pure water tank 122. The first pure water tank 122 is provided with a pump 26, and the pump 26 pumps up pure water in the first pure water tank 122. The pure water pumped up by the pump 26 is branched into a supply pipe 29 and an ion exchange circuit 124 that go to the oscillator 11 at the branching section 123.

The supply pipe 29 goes out of the first pure water tank 122 after passing through the cooler 28 in the first pure water tank 122. A supply sensor 29 extending from the cooler 28 is provided with a temperature sensor 50 and a pressure sensor 51.
Further, the supply pipe 29 is provided with two electric conductivity sensors 126 and 127 for measuring the purity of pure water in the supply pipe 29, and the electric conductivity sensors 128 and 129 are provided for the respective electric conductivity sensors. It has been. The electrical conductivity sensor and the electrical conductivity meter may not be plural, and may be provided in the first pure water tank 122.

  The ion exchange circuit 124 branched by the branch unit 123 is provided with an ion exchanger 130 and a valve 132 that turns on / off the introduction of pure water into the ion exchanger 130 on the upstream side of the ion exchanger 130. The ion exchange circuit 124 is piped so that pure water that has passed through the ion exchanger 130 returns to the pure water tank 122.

  The valve 132 and the ion exchanger 130 are connected by a fine tube 134 for controlling the flow rate of pure water introduced into the ion exchanger 130. A loop-shaped part 134a is formed in the middle part of the micropipe 134 by winding the micropipe 134 into a loop.

The loop-shaped part 134a is stuck to the outer wall surface of the first pure water tank 122 having a larger capacity than the second pure water tank 30 in order to prevent freezing.
As a method for attaching the loop-shaped portion 134a to the pure water tank 122, the method shown in FIGS. However, if the pure water tank 122 is not provided with a heat insulating material, the loop-shaped portion 134a may be simply attached to the outer wall surface of the tank with an adhesive tape or the like.

A circuit for supplying pure water to the optical system 12 will be described.
The circuit for supplying pure water to the optical system shown in FIG. 5 is provided with the electrical conductivity sensor 112 in the pure water tank 30, whereas the circuit for supplying pure water to the optical system 12 shown in FIG. Two electrical conductivity sensors 136 and 137 are provided in the pipe 35, and the electrical conductivity meters 138 and 139 are connected to the respective electrical conductivity sensors.
However, also in this embodiment, the electrical conductivity sensor and the electrical conductivity meter may not be plural, and may be provided in the second pure water tank 30.

The ion exchange circuit 42 in the circuit for supplying pure water to the optical system 12 has the same configuration as shown in FIG.
Further, the loop portion 44 a of the ion exchange circuit 42 is attached to the outer wall surface of the first pure water tank 122. As a method for attaching the loop-shaped portion 44a to the first pure water tank 122, the method shown in FIGS. However, when the first pure water tank 122 is not provided with a heat insulating material, the loop portion 44a may be simply attached to the outer wall surface of the tank with an adhesive tape or the like.
As described above, in this embodiment, the two loop-shaped portions 134 a and 44 a are both attached to the first pure water tank 122.

(Other embodiments)
In each of the embodiments described above, a structure in which the loop-shaped portion 44 a is attached to either the fresh water tank 24 or the first pure water tank 122 as the antifreezing structure of the micropipe 44 is employed.
However, the anti-freezing structure of the micropipe 44 is not limited to this. As shown in FIG. 7, the loop-shaped portion 44 a of the micropipe 44 is placed in the clean water of the fresh water tank 24 or the pure water of the first pure water tank 122. It may be immersed in water.
According to this configuration, freezing in the micropipe 44 can be prevented by directly exchanging heat with the cooling water in the tank.

  Further, in each of the above-described embodiments, the configuration in which the loop-shaped portion of the microtube is mainly heat-exchanged with the tank has been described. It is good also as a structure which can carry out heat exchange including it.

  In addition, as a liquid temperature control apparatus, it is not limited to the apparatus which can supply 2 systems of cooling water, The apparatus which can supply 1 system of cooling water may be sufficient, and 3 systems or more of cooling water can be supplied It may be a device.

DESCRIPTION OF SYMBOLS 10 Laser processing machine 11 Oscillator 12 Optical system 14 Heat insulating material 15 Recess 16 Lid 17 Hole 20 Liquid temperature control device 21 1st supply circuit 22 2nd supply circuit 24 Fresh water tank 26 Pump 28 Cooler 29 Supply pipe 30 Pure water tank 31 Return Pipe 32 Pump 34 Cooler 35 Supply pipe 36 Branch part 37 Return pipe 40 Ion exchanger 42 Ion exchange circuit 44 Fine pipe 44a Loop part 50 Temperature sensor 51 Pressure sensor 52 Valve 54 Bypass pipe 55 Bypass valve 57 Valve 58 Water supply pipe 60 Ball tap 61 Valve 62 Overflow drain pipe 63 Level gauge 64 Float switch 70 Refrigeration circuit 72 Compressor 75 Expansion valve 76 Expansion valve 77 Branching section 78 First flow path 79 Second flow path 80 Pressure sensor 82 Fan 84 Condenser 85 Strainer 86 Accumulator 87 Drain exhaust pipe 88 Heater 90 bar Lub 91 Valve 92 Constant flow valve 94 Valve 95 Fresh water supply pipe 96 Fresh water return pipe 98 Temperature sensor 100 Bypass pipe 102 Bypass valve 104 Water supply pipe 105 Drain pipe 106 Overflow exhaust pipe 108 Heater 109 Liquid level gauge 110 Float switch 112 Electric conductivity sensor 114 Electrical conductivity meter 120 Valve 122 Pure water tank 123 Branch 124 Ion exchange circuit 126 Electrical conductivity sensor 127 Electrical conductivity sensor 128 Electrical conductivity meter 129 Electrical conductivity meter 130 Ion exchanger 132 Valve 134 Micro tube 134a Loop shape Part 136 Electrical conductivity sensor 137 Electrical conductivity sensor 138 Electrical conductivity meter 139 Electrical conductivity meter 200 Liquid temperature control device

Claims (8)

A tank for storing cooling water;
A supply pipe for circulating cooling water from the tank to the object to be cooled;
A return pipe for circulating cooling water returned from the object to be cooled to the tank;
A temperature controller for controlling the temperature of the cooling water;
An ion exchanger for removing ions from the cooling water;
An ion exchange circuit branched in the middle of the supply pipe to introduce a part of the cooling water into the ion exchanger, and to introduce the cooling water flowing out from the ion exchanger into the tank;
A fine tube provided upstream of the ion exchanger in the ion exchange circuit;
A liquid temperature control comprising: a freeze prevention mechanism for preventing freezing of the cooling water in the fine pipe by exchanging heat between the fine pipe and the tank or the cooling water in the tank. apparatus. The anti-freezing mechanism is
The liquid temperature control apparatus according to claim 1, wherein the fine pipe is attached to an outer wall surface of the tank. A heat insulating material covering the entire outer wall surface of the tank is provided;
The anti-freezing mechanism is
A part of the heat insulating material is cut off so that the outer wall surface of the tank is exposed in accordance with the shape of the micropipe, and a recess is formed. The micropipe is stored in the recess and the micropipe is stored. 2. The liquid temperature control apparatus according to claim 1, wherein the surface of the recess is closed by another heat insulating material. The anti-freezing mechanism is
2. The liquid temperature control apparatus according to claim 1, wherein the fine pipe is configured to be immersed in cooling water of the tank. A plurality of tanks for storing cooling water;
A plurality of supply pipes for circulating cooling water from each tank to an object to be cooled;
A plurality of return pipes for circulating cooling water returned from the object to be cooled to each tank;
A plurality of temperature controllers for controlling the temperature of the cooling water;
Among the cooling water flowing through each of the plurality of supply pipes, one or a plurality of ion exchangers for removing ions with respect to cooling water that requires ion removal,
A part of the cooling water is introduced into the ion exchanger by branching in the middle of one or a plurality of supply pipes through which the cooling water requiring ion removal is circulated, and each of the cooling water flowing out from the ion exchanger is One or more ion exchange circuits to be introduced into the tank;
One or more microtubules provided on the upstream side of the ion exchanger in each of the ion exchange circuits;
Of each of the tanks, heat exchange is performed with either a large capacity tank or a tank having a high set temperature, or a cooling water in a tank having a large capacity or a cooling water in a tank having a high set temperature. 1 or a plurality of anti-freezing mechanisms for preventing freezing of the cooling water in the micropipe. The anti-freezing mechanism is
6. The liquid temperature control apparatus according to claim 5, wherein the fine pipe is adhered to an outer wall surface of either a tank having a large capacity or a tank having a high set temperature. A heat insulating material covering the entire outer wall surface of each tank is provided;
The anti-freezing mechanism is
A part of the heat insulating material covering the outer wall surface of either the large capacity tank or the tank having a high set temperature is cut off so that the outer wall surface of the tank is exposed in accordance with the shape of the fine tube, and a recess is formed. 6. The liquid temperature control apparatus according to claim 5, wherein a fine tube is accommodated in the recess, and the surface of the recess in which the fine tube is accommodated is closed with another heat insulating material. The anti-freezing mechanism is
6. The liquid temperature control apparatus according to claim 5, wherein the fine pipe is configured to be immersed in cooling water of a tank having a large capacity or a tank having a high set temperature.

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