JP2016151374A - Cooling device - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a cooling device which can acquire high cooling capacity while preventing dew condensation, and in which power consumption becomes smaller.SOLUTION: A cooling device includes: a cooling plate 3 having a refrigerant chamber 11; a gas-liquid separator 16 having a gas-liquid separation chamber 18; a first refrigerant passage 15 for connecting a lower end part of the refrigerant chamber 11 and a lower end part of the gas-liquid separation chamber 18; and a second refrigerant passage 14 for connecting an upper end part of the refrigerant chamber 11 and an upper end part of the gas-liquid separation chamber 18. The cooling device includes a first condenser 25 and a heat exchanger 26 provided in the second refrigerant passage 14 and located above the cooling plate 3 and the gas-liquid separator 16. The cooling device includes a compressor 33, a second condenser 34, and an electronic expansion valve 35 of a third refrigerant passage 31 passing through the heat exchanger 26. The cooling device includes a control device 6 for compressor control. A first refrigerant 12 vaporizes by being heated by the heat of an object 2 to be cooled in the refrigerant chamber 11, and also the first refrigerant liquefies by being cooled by the atmosphere in the first condenser 25.SELECTED DRAWING: Figure 1

Description

  The present invention relates to a cooling device that cools an endothermic member in contact with an object to be cooled with a refrigerant.

  Conventionally, as a conventional cooling device for cooling a high-density heat source, there are a cooling device called a chiller (hereinafter simply referred to as a chiller device), a device described in Patent Document 1, and the like. The chiller device cools cooling water using a refrigeration cycle, and cools an object to be cooled with this cooling water. This chiller device includes electric components such as a compressor for compressing refrigerant and a cooling water pump for circulating cooling water.

  The cooling device described in Patent Document 1 cools an endothermic member in contact with an object to be cooled on the principle of a refrigeration cycle. The heat absorbing member has a refrigerant chamber through which the refrigerant of the refrigeration cycle flows. The refrigeration cycle includes a compressor that compresses the refrigerant, a condenser that cools the refrigerant, an expansion valve that expands the refrigerant, a gas-liquid separator, an accumulator, an evaporator, and the like that are provided downstream of the expansion valve. .

  The gas-liquid separator has a gas-liquid separation chamber that separates a liquid refrigerant and a gaseous refrigerant. The lower end portion of the gas-liquid separation chamber is connected to the upper end portion of the refrigerant chamber of the heat absorbing member by the first refrigerant passage. The upper portion of the gas-liquid separation chamber is connected to the upper end portion of the refrigerant chamber of the heat absorbing member by the second refrigerant passage. For this reason, the liquid refrigerant stored in the gas-liquid separation chamber flows down into the heat absorbing member through the first refrigerant passage. The refrigerant in the heat absorbing member is vaporized by transferring the heat of the object to be cooled. This refrigerant gas flows into the gas-liquid separation chamber through the second refrigerant passage. The refrigerant gas in the gas-liquid separation chamber is sucked into the compressor through the accumulator and the evaporator.

JP 2007-294877 A

In the above-described conventional chiller device, since the temperature of the cooling water is lower than the atmospheric temperature, the condensed water generated by the condensation may cause a problem in the object to be cooled and the surrounding electrical equipment. In addition, there is a problem that electric equipment for generating power such as a motor for driving a compressor and a motor for driving a cooling water pump is required, and power consumption increases. The problem of increased power consumption also occurs in the cooling device disclosed in Patent Document 1.
In the chiller device, the cooling water may leak. If the cooling water leaks, there is a risk of problems in the object to be cooled and the surrounding electrical equipment. In addition, since this type of cooling device cools by so-called sensible heat change, there is a limit to increasing the cooling efficiency.

  The present invention has been made to solve such a problem, and an object of the present invention is to provide a cooling device that can obtain high cooling capacity while preventing condensation and that consumes less power.

  In order to achieve this object, a cooling device according to the present invention has a refrigerant chamber through which a first refrigerant flows, a heat absorbing member to which heat of an object to be cooled is transmitted, and the gaseous first refrigerant, A gas-liquid separator having a gas-liquid separation chamber for separating the liquid first refrigerant, a first refrigerant passage connecting the lower end of the refrigerant chamber and the lower end of the gas-liquid separation chamber, A second refrigerant passage connecting the upper end portion of the refrigerant chamber and the upper end portion of the gas-liquid separation chamber, and in the middle of the second refrigerant passage, at a position higher than the heat absorbing member and the gas-liquid separator. A first condenser that cools the first refrigerant by the atmosphere, and is provided in parallel with the first condenser in the second refrigerant passage, and is different from the first refrigerant. Provided in the middle of the third refrigerant passage through which the second refrigerant flows, and the heat of the first refrigerant is transferred to the second refrigerant passage. A heat exchanger to be transmitted to the medium, a compressor provided downstream of the heat exchanger in the third refrigerant passage, and compressing the second refrigerant, and downstream of the compressor in the third refrigerant passage A second condenser for cooling the second refrigerant discharged from the compressor, and an expansion valve provided between the second condenser and the heat exchanger in the third refrigerant passage. And a control device for controlling the rotation of the compressor, wherein the first refrigerant is vaporized by being heated by the heat of the object to be cooled in the refrigerant chamber and by the atmosphere in the first condenser. It is cooled and liquefied, and the second refrigerant is liquefied by being cooled by a second condenser, expanded through the expansion valve, and vaporized in a heat exchanger. It is characterized by Than is.

  The present invention further includes a sensor that detects a temperature of the heat absorbing member in the cooling device, and the control device is configured such that the temperature of the heat absorbing member detected by the sensor is equal to or lower than a preset temperature. In the case where the compressor is stopped and the temperature of the heat absorbing member is higher than the set temperature, the compressor may have a function of operating.

  According to the present invention, in the cooling device, the control device has a function of gradually increasing the rotation speed of the compressor when the temperature of the heat absorbing member detected by the sensor is higher than the set temperature, and the sensor. In the case where the detected temperature of the heat absorbing member is equal to or lower than the set temperature, the heat absorbing member may have a function of gradually decreasing the rotation speed of the compressor.

  In the cooling device, the present invention may further include a fan that blows air to the second refrigerant passage.

  In the cooling device according to the present invention, the first refrigerant and the second refrigerant may be alternative chlorofluorocarbons.

The cooling device according to the present invention can adopt a first operation mode in which the compressor is stopped and a second operation mode in which the compressor is operated.
When the first operation mode is adopted, the heat of the object to be cooled is transmitted to the first refrigerant stored in the refrigerant chamber of the heat absorbing member. This first refrigerant is vaporized by the heat of the object to be cooled. At this time, the heat absorbing member is cooled by taking heat energy corresponding to latent heat of vaporization when the first refrigerant is vaporized. Cooling of the heat absorbing member means that the object to be cooled is cooled. The thermal energy taken away by cooling using the latent heat of vaporization is greater than when cooling is a sensible heat reaction.

Further, by performing the cooling using the latent heat of vaporization in this way, the heat absorbing member can be uniformly cooled. In the case of cooling by sensible heat reaction with water, when the low-temperature water flowing from the inlet reaches the outlet, the temperature becomes relatively high. For this reason, a temperature difference occurs between the inlet side and the outlet side. However, when cooling is performed using the latent heat of vaporization, the refrigerant evaporates substantially uniformly in the heat absorbing member, so that the temperature distribution of the heat absorbing member becomes substantially uniform as described above.
That is, according to this cooling device, cooling can be performed more efficiently than when cooling is performed using cooling water.

  The refrigerant gas generated by the vaporization of the first refrigerant in the refrigerant chamber rises in the refrigerant chamber because the specific gravity is smaller than that of the liquid refrigerant, and the first condensation passes from the upper part of the refrigerant chamber through the second refrigerant passage. Flows into the vessel. The refrigerant is partially or mostly liquefied by being cooled by the first condenser, and flows down to the gas-liquid separation chamber of the gas-liquid separator through the second refrigerant passage by gravity. The liquid refrigerant and the gaseous refrigerant are separated in the gas-liquid separator chamber.

The liquid refrigerant flows from the gas-liquid separator through the first refrigerant passage by gravity into the refrigerant chamber of the heat absorbing member. Therefore, in the first cooling mode, the first refrigerant circulates through the heat absorbing member, the first condenser, and the gas-liquid separator without using a circulation pump. In this cooling device, the electric power required for the first refrigerant to circulate in this way is zero.
The first condenser cools the first refrigerant by the atmosphere. For this reason, in this cooling device, in the first cooling mode, the temperature of the first refrigerant does not fall below the atmospheric temperature, so that condensation is unlikely to occur.

  When the second operation mode is adopted, the second refrigerant is cooled by the second condenser of the second refrigerant discharged from the compressor to the third refrigerant passage, and further passes through the expansion valve in the heat exchanger. Vaporize. A second refrigerant passage is also present in the heat exchanger. For this reason, in the heat exchanger, thermal energy corresponding to the latent heat of vaporization when the second refrigerant is vaporized is taken away from the first refrigerant flowing through the second refrigerant passage. That is, the first refrigerant is cooled in the heat exchanger. For this reason, by adopting the second operation mode, liquefaction and cooling of the first refrigerant are promoted, and the cooling capacity of the heat absorbing member is increased.

According to this cooling device, by adopting the first operation mode, it is possible to perform cooling with low power consumption and high efficiency as compared with the case of using cooling water, and condensation does not occur. . When the cooling capacity is insufficient in the first operation mode, the shortage of the cooling capacity can be compensated by adopting the second operation mode. In the second operation mode, the compressor is operated to increase power consumption. However, the power consumption is lower than that of the conventional cooling device in which the compressor is always operated.
Therefore, according to the present invention, it is possible to provide a cooling device that can obtain high cooling capacity while preventing condensation and that consumes less power.

It is a systematic diagram which shows the structure of the cooling device which concerns on this invention. It is a perspective view which shows the principal part of the cooling device which concerns on this invention. It is a perspective view which shows a refrigerating cycle part. It is a perspective view which shows a natural circulation cycle part. It is sectional drawing which shows the state of an endothermic part typically. It is a block diagram which shows the structure of an inverter control part. It is a flowchart for demonstrating operation | movement of the cooling device which concerns on this invention. It is a graph for comparing the capability of the cooling device of the present invention and a chiller device. 8A is a graph showing the capability of the cooling device of the present invention, FIG. 8B is a graph showing the capability of the chiller device, and FIG. 8C is a graph showing the capability of the cooling device and the chiller device of the present invention. It is. It is a graph for comparing a cooling rate. It is a graph for comparing a cooling rate.

Hereinafter, an embodiment of a cooling device according to the present invention will be described in detail with reference to FIGS.
A cooling device 1 shown in FIG. 1 is for cooling an object 2 to be cooled, which is a high-density heat source, and includes a cooling plate 3 that contacts the object 2 to be cooled. The heat of the object to be cooled 2 is transmitted to the cooling plate 3 by conduction. In addition, the cooling device 1 includes a housing 4 (see FIG. 2) surrounding other components excluding the cooling plate 3.

  As shown in FIGS. 2 and 3, the cooling plate 3 is formed in a plate shape with a metal having high thermal conductivity, and is placed upright on the lower portion of the housing 4 with the main surface oriented in the horizontal direction. ing. The cooling plate 3 is exposed on one side of the housing 4. The cooling plate 3 includes a temperature sensor 5 (see FIG. 1). The temperature sensor 5 sends the temperature of the cooling plate 3 as a signal to the control device 6 described later. In this embodiment, the cooling plate 3 constitutes a “heat absorbing member” in the present invention.

  A refrigerant chamber 11 is formed inside the cooling plate 3. A liquid first refrigerant 12 (see FIG. 1) is stored in the refrigerant chamber 11. The first refrigerant 12 according to this embodiment is an alternative chlorofluorocarbon (HFC-134a). In addition, the kind of the 1st refrigerant | coolant 12 is not limited to a substitute Freon, For example, ammonia and water may be sufficient. When water is used, the inside of the refrigerant chamber 11 is depressurized in order to lower the boiling point.

  The heat transferred from the object to be cooled 2 to the cooling plate 3 is transferred to the liquid first refrigerant 12 in the refrigerant chamber 11 to heat the first refrigerant 12 as schematically shown in FIG. . The liquid first refrigerant 12 boils and vaporizes as the temperature rises, and becomes a refrigerant gas 12a. That is, the cooling plate 3 is cooled by taking heat energy corresponding to the latent heat of vaporization when the first refrigerant 12 is vaporized. In this way, the cooling plate 3 is cooled by the first refrigerant 12, whereby the object to be cooled 2 is cooled. The thermal energy taken away by cooling using the latent heat of vaporization is greater than when cooling is a sensible heat reaction.

  The refrigerant gas 12 a rises in the refrigerant chamber 11 because the specific gravity is smaller than that of the liquid first refrigerant 12. The refrigerant chamber 11 is divided into a refrigerant liquid layer 11a in which the liquid first refrigerant 12 is stored and a refrigerant gas layer 11b in which the refrigerant gas 12a is stored. The refrigerant gas 12 a in the refrigerant chamber 11 flows out from the upper end portion of the refrigerant chamber 11 into the second refrigerant passage 14 described later.

As shown in FIG. 1, the lower end portion of the refrigerant chamber 11 of the cooling plate 3 is connected to the lower end portion of the gas-liquid separator 16 by the first refrigerant passage 15. As shown in FIG. 3, the first refrigerant passage 15 is formed by a plurality of pipe members 17.
The gas-liquid separator 16 has a gas-liquid separation chamber 18 that separates the gaseous first refrigerant 12 and the liquid first refrigerant 12, and as shown in FIGS. 2 and 3, the cooling plate 3 is arranged at a position adjacent to the horizontal direction.

  The gas-liquid separator 16 according to this embodiment is installed with its upper end located at the same height as the upper end of the cooling plate 3. As shown in FIG. 1, the liquid level of the liquid refrigerant stored in the gas-liquid separator 16 and the cooling plate 3 is above the cooling plate 3 and above the portion in contact with the object 2 to be cooled. Is located. When the first refrigerant 12 in the cooling plate 3 is vaporized and flows out of the refrigerant chamber 11, the first refrigerant 12 is newly replenished to the refrigerant chamber 11 from the gas-liquid separator 16.

The upper end portion of the gas-liquid separator 16 (gas-liquid separation chamber 18) is connected to the upper end portion of the cooling plate 3 (refrigerant chamber 11) via the second refrigerant passage 14.
The second refrigerant passage 14 has a plurality of pipes 21 connected to the upper end of the cooling plate 3 and upstream pipes 22 (see FIG. 3) and a plurality of gas pipes connected to the upper end of the gas-liquid separator 16. And a first condenser 25 and a heat exchanger 26 provided between the two pipe lines 22 and 24.

  The first condenser 25 cools the first refrigerant 12 flowing through the second refrigerant passage 14 by the atmosphere, and as shown in FIG. 3, a pipe 27 and cooling fins (FIG. 3) through which the first refrigerant 12 flows. Not shown). The pipe 27 is formed by a plurality of cooling parts (not shown) that traverse the inside of the first condenser 25 in the horizontal direction and a bent part 27a that connects these cooling parts. The upstream end of the pipe 27 located at the upper end of the first condenser 25 is connected to the upstream conduit 22. The downstream end of the pipe 27 located at the lower end of the first condenser 25 is connected to the downstream conduit 24. As the first refrigerant 12 according to this embodiment, a refrigerant that is cooled and liquefied by the atmosphere in the first condenser 25 is used.

  As shown in FIGS. 2 and 3, the first condenser 25 is provided in the middle of the second refrigerant passage 14 and at a position higher than the cooling plate 3 and the gas-liquid separator 16. Therefore, the first refrigerant 12 cooled and liquefied by the first condenser 25 flows down to the gas-liquid separator 16 through the downstream pipe line 24 due to gravity.

As shown in FIG. 1, the heat exchanger 26 is provided in parallel with the first condenser 25 in the second refrigerant passage 14 so that the first refrigerant portion 28 through which the first refrigerant 12 flows, It has the 2nd refrigerant | coolant part 29 through which the 2nd refrigerant | coolant (not shown) different from the refrigerant | coolant 12 flows. The second refrigerant is equivalent to the first refrigerant 12 and is enclosed in a third refrigerant passage 31 described later. That is, the heat exchanger 26 is provided in the second refrigerant passage 14 in parallel with the first condenser 25 and is provided in the middle of the third refrigerant passage 31.
The first refrigerant part 28 and the second refrigerant part 29 of the heat exchanger 26 have a function of transferring the heat of the first refrigerant 12 to the second refrigerant.
Hereinafter, a portion through which the first refrigerant 12 such as the cooling plate 3, the gas-liquid separator 16, the first condenser 25, and the heat exchanger 26 passes is simply referred to as “natural circulation cycle section 32”.

  The second refrigerant section 29 of the heat exchanger 26 is for performing a vaporization process of a refrigeration cycle using the second refrigerant. In the refrigeration cycle, the compression stroke performed by the compressor 33 located downstream of the heat exchanger 26 in the third refrigerant passage 31 and the cooling performed by the second condenser 34 provided downstream of the compressor 33. Process, expansion stroke performed by the electronic expansion valve 35 provided between the second condenser 34 and the heat exchanger, vaporization stroke performed in the second refrigerant section 29 of the heat exchanger 26 described above, and the like It is constituted by.

  The downstream end portion of the second refrigerant portion 29 is located at the upper end portion of the heat exchanger 26, and as shown in FIG. 4, the compressor 33 is connected to the compressor 33 by a first conduit 37 made up of a plurality of tube members 36. It is connected to the refrigerant inlet 33a. The refrigerant outlet portion 33 b of the compressor 33 is connected to the upper end portion of the second condenser 34 by a second pipe line 39 including a plurality of pipe members 38.

  The compressor 33 is driven by a motor (not shown) to compress the second refrigerant and discharge it to the second conduit 39. The compressor 33 is a so-called sensorless one that does not include a sensor for detecting the rotation of the rotating shaft. The motor for driving the compressor is accommodated in the compressor housing 40. The operation of the motor (rotation of the compressor) is controlled by a control device 6 described later.

  The second condenser 34 cools the second refrigerant discharged from the compressor 33 by the atmosphere, and includes a pipe 41 through which the second refrigerant flows and cooling fins (not shown). The second refrigerant is liquefied by being cooled by the second condenser 34. The pipe 41 of the second condenser 34 is formed by a plurality of cooling parts (not shown) that cross the inside of the second condenser 34 in the horizontal direction and a bent part 41a that connects these cooling parts. ing. The upstream end of the pipe located at the upper end of the second condenser 34 is connected to the second conduit 39. Further, the downstream end of the pipe 41 located at the lower end of the second condenser 34 is connected to the heat exchanger 26 via a third conduit 43 composed of a plurality of tube members 42 and the electronic expansion valve 35. It is connected to the lower end (upstream end of the second refrigerant portion 29).

As shown in FIG. 2, the second condenser 34 according to this embodiment is installed side by side in the horizontal direction with the first condenser 25 described above. In addition, an electric cooling fan 44 that blows air to the first and second condensers 25 and 34 is disposed on the opposite side of the second condenser 34 from the first condenser 25. . The operation of the cooling fan 44 is controlled by the control device 6.
The electronic expansion valve 35 depressurizes the second refrigerant cooled and liquefied by the second condenser 34. The second refrigerant decompressed by the electronic expansion valve 35 is vaporized in the heat exchanger 26 and takes heat energy corresponding to the latent heat of vaporization when vaporized from the first refrigerant unit 28. For this reason, the first refrigerant 12 flowing through the first refrigerant section 28 in the heat exchanger 26 is cooled and liquefied in the heat exchanger 26, and passes through the downstream pipe line 24 due to gravity, whereby the gas-liquid separator. It flows down to 16.
Hereinafter, a portion through which the second refrigerant such as the heat exchanger 26, the compressor 33, the second condenser 34, and the electronic expansion valve 35 passes is simply referred to as a “refrigeration cycle unit 45”.

  The control device 6 has a plurality of functional units to be described later and adopts a configuration for switching between a first operation mode in which the compressor 33 is stopped and a second operation mode in which the compressor 33 is operated. . When the first operation mode is adopted, cooling is performed only by the natural circulation cycle unit 32. When the second operation mode is adopted, cooling is performed using both the natural circulation cycle unit 32 and the refrigeration cycle unit 45.

  The plurality of functional units of the control device 6 are an expansion valve control unit 51, a cooling fan control unit 52, a temperature setting unit 53, and an inverter control unit 54, as shown in FIG. The expansion valve control unit 51 controls the opening degree of the electronic expansion valve 35. The cooling fan control unit 52 switches the cooling fan 44 on and off. The temperature setting unit 53 is for setting a cooling temperature targeted by an operator (not shown).

  As shown in FIG. 6, the inverter control unit 54 includes a rotation command unit 55, a control voltage conversion unit 56, a PWM conversion unit 57, a winding voltage value and winding current value acquisition unit 58, and a phase estimation unit 59. Etc., and controls operations such as rotation and stop of the compressor driving motor and increase and decrease of the rotation speed (frequency).

Next, the operation of the cooling device 1 configured as described above will be described using the flowchart shown in FIG.
The cooling device 1 according to this embodiment starts operation when a main switch (not shown) shifts from the OFF state to the ON state in step S1. The control device 6 is activated when the main switch is turned on.
The controller 6 sets the opening degree of the electronic expansion valve 35 to a predetermined opening degree and rotates the cooling fan 44 in step S1 after activation. In step S1, the control device 6 keeps the compressor driving motor stopped. That is, at the start of operation, the cooling device 1 is operated in the first operation mode that uses only the natural circulation cycle unit 32. In this way, the object to be cooled 2 is brought into contact with the cooling plate 3 while the cooling device 1 is operated in the first operation mode.

  Next, in step S2, the control device 6 determines whether or not the current temperature of the cooling plate 3 is higher than a preset temperature. This set temperature is a target temperature set by the operator using the temperature setting unit 53. When the temperature of the cooling plate 3 is lower than the set temperature, the control device 6 determines whether or not the compressor 33 is operating in step S3. When the compressor 33 is not operating, the process returns to step S2 and the control flow described above is repeated. In other words, when the object to be cooled 2 can be sufficiently cooled in the first operation mode, Step S2 and Step S3 are repeated, and only the natural circulation cycle unit 32 is cooled.

  When the first operation mode is adopted, the refrigerant gas 12 a generated in the refrigerant chamber 11 of the cooling plate 3 is mainly cooled by the first condenser 25. Part or most of the first refrigerant 12 is liquefied in the first condenser 25 and flows down to the gas-liquid separation chamber 18 of the gas-liquid separator 16 by gravity. The liquid first refrigerant 12 and the gaseous first refrigerant 12 are separated in the gas-liquid separator 16 chamber.

When the first refrigerant 12 in the cooling plate 3 decreases, the liquid first refrigerant 12 passes from the gas-liquid separator 16 through the first refrigerant passage 15 to the refrigerant chamber 11 of the cooling plate 3 due to gravity. Inflow. For this reason, in the first operation mode, the first refrigerant 12 circulates in the natural circulation cycle unit 32 without using a circulation pump. In the cooling device 1, the power necessary for the first refrigerant 12 to circulate in this way is only power for driving the cooling fan 44.
The 1st condenser 25 cools the 1st refrigerant | coolant 12 with air | atmosphere. For this reason, in the cooling device 1, in the first cooling mode, the temperature of the first refrigerant 12 does not become the atmospheric temperature or less, so that condensation does not easily occur.

  When it is determined in step S2 that the temperature of the cooling plate 3 is higher than the set temperature, the control device 6 determines in step S4 whether or not the compressor 33 is operating. At this time, if the compressor 33 is not operating, the process proceeds to step S5, and the control device 6 starts the compressor 33. The rotation speed at the start of the compressor 33 is a predetermined minimum rotation speed Min. When the compressor 33 starts operation, the first operation mode is shifted to the second operation mode, and cooling is performed by both the natural circulation cycle unit 32 and the refrigeration cycle unit 45.

The control device 6 performs inverter optimization control in step S6 after starting the compressor 33. The inverter optimization control is control for stabilizing the rotation of the compressor driving motor.
By operating the compressor 33, the second refrigerant discharged from the compressor 33 into the third refrigerant passage 31 is cooled by the second condenser 34, and further passes through the electronic expansion valve 35 to heat exchanger 26. It vaporizes in the 2nd refrigerant | coolant part 29 of an inside. A first refrigerant portion 28 exists at a position adjacent to the second refrigerant portion 29 in the heat exchanger 26. For this reason, in the heat exchanger 26, thermal energy corresponding to latent heat of vaporization when the second refrigerant is vaporized is taken away from the first refrigerant 12 flowing through the first refrigerant portion 28. That is, the first refrigerant 12 is cooled in the heat exchanger 26. For this reason, by adopting the second operation mode, liquefaction and cooling of the first refrigerant 12 are promoted, and the cooling capacity of the cooling plate 3 is increased.

  If the temperature of the cooling plate 3 is higher than the set temperature even when the second operation mode is adopted and the compressor 33 is operating, the process proceeds from step S2 to step S4 to step S7, and the control device 6 is used for driving the compressor Increase the frequency to drive the motor. That is, when the temperature of the cooling plate 3 is higher than the set temperature while the compressor 33 is being operated, the rotational speed of the compressor 33 gradually increases.

  On the other hand, when it is determined in step S2 that the temperature of the cooling plate 3 is equal to or lower than the set temperature, the control device 6 proceeds from step S2 to step S3 to step S8, and the frequency for driving the compressor driving motor is determined. It is determined whether or not it is the lowest value. If this frequency is not the lowest value, the control device 6 lowers the frequency for driving the compressor driving motor in step S9. That is, when the temperature of the cooling plate 3 is equal to or lower than the set temperature while the compressor 33 is being operated, the rotational speed of the compressor 33 gradually decreases.

  If it is determined in step S8 that the frequency is the lowest value, the controller 6 stops the compressor driving motor in step S10. That is, when the temperature of the cooling plate 3 detected by the temperature sensor 5 is equal to or lower than a predetermined set temperature, the control device 6 stops the compressor 33 and the temperature of the cooling plate 3 is higher than the set temperature. Has a function of bringing the compressor 33 into an operating state.

  When the cooling device 1 according to this embodiment was prototyped and actually operated, results as shown in FIGS. 8 to 10 were obtained. FIG. 8A shows the capacity of the cooling device 1 according to this embodiment in the first operation mode (when cooling is performed only by the natural circulation cycle unit 32) and in the second operation mode (refrigeration). Capacity when the cycle unit 45 is also operated to perform cooling). FIG. 8B shows the cooling capacity of the chiller device. FIG. 8C is a stack of FIG. 8A and FIG. 8B. 8A to 8C, the vertical axis represents the heater load, and the horizontal axis represents the temperature difference between the cooling plate and the ambient temperature. Moreover, COP (coefficient of performance) is described in FIGS. The COP can be obtained by dividing the cooling capacity by the power consumption.

As can be seen from FIG. 8B, the COP of the chiller device is low, and the ratio of the cooling capacity to the power consumption is about three times.
However, according to the cooling device 1 of this embodiment, the COP can be greatly improved if the temperature of the cooling plate 3 can tolerate a temperature difference from the ambient temperature.
As can be seen from FIG. 8 (C), when the cooling capacity is insufficient by the operation of only the natural circulation cycle unit 32, it is equivalent to the chiller device by operating the refrigeration cycle unit 45 having the inverter 33 controlled by the inverter. The cooling capacity can be obtained. At this time, the COP can be greatly improved as compared with the chiller device, and an energy saving effect can be obtained.

The refrigeration cycle unit 45 of the cooling device 1 according to this embodiment and the primary cycle unit of the chiller device are both configured to use a compressor, but the secondary cycle unit of the chiller device supplies cooled water. A pump is needed to send. What is the power consumption of the cooling fan 44 used in the natural circulation part of the cooling device 1 according to this embodiment? Less than the power consumption of the pump. That is, the chiller device consumes more power than the cooling device 1 according to this embodiment by the difference in power consumption.
In the cooling device 1 according to this embodiment, the cooling capacity of the natural circulation cycle unit 32 is obtained so as to allow the difference between the temperature of the cooling plate 3 and the ambient temperature, and the rotational speed of the compressor 33 of the refrigeration cycle unit 45 is kept low. Therefore, a great energy saving effect can be obtained.

FIG. 9 is a graph comparing the cooling rate when cooling is performed in the natural circulation cycle unit 32 according to this embodiment and when cooling is performed using a heat sink (not shown). In cooling using the heat sink, air was blown onto the heat sink with a cooling fan having the same performance as the cooling fan 44 used in this embodiment.
As can be seen from FIG. 9, the time required for cooling the cooling plate 3 at 100 ° C. to 50 ° C. required about 8 seconds for the natural circulation cycle section 32 and about 18 seconds for the heat sink. The cooling rate of the natural circulation cycle part 32 was more than twice the cooling rate of the heat sink.

FIG. 10 shows a case where cooling is performed by the natural circulation cycle unit 32 according to this embodiment, a case where cooling is performed with water at an ambient temperature by a chiller device, and a case where water cooled to ambient temperature by a fan is circulated by a pump. It is the graph which compared the cooling rate about the case where it cools.
As can be seen from FIG. 10, the cooling rates of these three cooling systems were equivalent. This means that the natural circulation cycle unit 32 according to this embodiment can be cooled at a cooling rate equivalent to water cooling, and the power consumption is the smallest among these three cooling methods.

In the cooling device 1 according to this embodiment configured as described above, the thermal energy taken away by the cooling plate 3 using the latent heat of vaporization is increased compared to the case where the cooling is a sensible heat reaction. . In addition, the cooling plate 3 can be uniformly cooled by performing the cooling using the latent heat of vaporization. In the case of cooling by sensible heat reaction with water, when the low-temperature water flowing from the inlet reaches the outlet, the temperature becomes relatively high. For this reason, a temperature difference occurs between the inlet side and the outlet side. However, when cooling is performed using the latent heat of vaporization, the refrigerant evaporates substantially uniformly in the cooling plate 3, so that the temperature distribution of the cooling plate 3 becomes substantially uniform as described above.
That is, according to this cooling device 1, it can cool more efficiently than the case where it cools using cooling water.
The 1st condenser 25 cools the 1st refrigerant | coolant 12 with air | atmosphere. For this reason, in the cooling device 1, in the first cooling mode, the temperature of the first refrigerant 12 does not become the atmospheric temperature or less, so that condensation does not easily occur.

For this reason, according to this cooling device 1, by adopting the first operation mode, it is possible to perform cooling with low power consumption and high efficiency as compared with the case where cooling water is used, and in addition, condensation is generated. Cooling can be performed without occurring. When the cooling capacity is insufficient in the first operation mode, the shortage of the cooling capacity can be compensated by adopting the second operation mode. In the second operation mode, the compressor 33 is operated to increase power consumption. However, the power consumption is less than that of a conventional cooling device in which the compressor is always operated, such as a chiller device.
Therefore, according to this embodiment, it is possible to provide a cooling device that can obtain a high cooling capacity while preventing condensation and that consumes less power.

The cooling device 1 according to this embodiment includes a temperature sensor 5 that detects the temperature of the cooling plate 3. When the temperature of the cooling plate 3 detected by the temperature sensor 5 is equal to or lower than a predetermined set temperature (target temperature), the control device 6 stops the compressor 33 and the temperature of the cooling plate 3 is set to the set temperature ( When the temperature is higher than the target temperature, the compressor 33 has a function of operating.
For this reason, according to this embodiment, since the 1st operation form and the 2nd operation form change automatically, the to-be-cooled object 2 can be cooled, suppressing electric power consumption as much as possible.

The control device 6 according to this embodiment has a function of gradually increasing the rotational speed of the compressor 33 when the temperature of the cooling plate 3 detected by the temperature sensor 5 is higher than a set temperature (target temperature), and the temperature sensor 5. When the temperature of the cooling plate 3 detected by the above is equal to or lower than the set temperature (target temperature), it has a function of gradually decreasing the rotational speed of the compressor 33.
For this reason, according to this embodiment, since the rotation speed of the compressor 33 changes according to the temperature of the article 2 to be cooled, the power consumption is minimized.

  The first condenser 25 according to this embodiment includes a cooling fan 44 that blows air to the first refrigerant passage 14. For this reason, since the efficiency which cools the 1st refrigerant | coolant 12 becomes high, the cooling device from which cooling efficiency becomes still higher can be provided. Moreover, since the small 1st condenser 25 can be used, there also exists an effect that a compact cooling device is realizable.

  The first refrigerant 12 and the second refrigerant according to this embodiment are alternative chlorofluorocarbons. For this reason, unlike the case where cooling water is used, even if the 1st and 2nd refrigerant | coolant 12 leaks, a malfunction will not arise in an electric equipment. Therefore, according to this embodiment, it is possible to provide a cooling device that is not restricted by the place of use.

  DESCRIPTION OF SYMBOLS 1 ... Cooling device, 2 ... Object to be cooled, 3 ... Cooling plate (heat absorption member), 5 ... Temperature sensor (sensor), 6 ... Control device, 11 ... Refrigerant chamber, 12 ... First refrigerant, 12a ... Refrigerant gas ( Gaseous first refrigerant), 14 ... second refrigerant passage, 15 ... first refrigerant passage, 16 ... gas-liquid separator, 18 ... gas-liquid separation chamber, 25 ... first condenser, 26 ... heat Exchanger 31 ... second refrigerant passage 33 ... compressor 34 ... second condenser 35 ... electronic expansion valve 44 ... cooling fan (fan).

Claims (5)

A heat-absorbing member having a refrigerant chamber through which the first refrigerant flows, to which heat of the object to be cooled is transmitted;
A gas-liquid separator having a gas-liquid separation chamber for separating the gaseous first refrigerant and the liquid first refrigerant;
A first refrigerant passage connecting the lower end of the refrigerant chamber and the lower end of the gas-liquid separation chamber;
A second refrigerant passage connecting the upper end of the refrigerant chamber and the upper end of the gas-liquid separation chamber;
A first condenser that is provided in the middle of the second refrigerant passage and is higher than the heat absorbing member and the gas-liquid separator, and cools the first refrigerant by the atmosphere;
The first refrigerant passage is provided in parallel with the first condenser, and is provided in the middle of a third refrigerant passage through which a second refrigerant different from the first refrigerant flows. A heat exchanger for transferring the heat of the refrigerant to the second refrigerant;
A compressor provided on the downstream side of the heat exchanger in the third refrigerant passage, and compresses the second refrigerant;
A second condenser that is provided downstream of the compressor in the third refrigerant passage and cools the second refrigerant discharged from the compressor;
An expansion valve provided between the second condenser and the heat exchanger in the third refrigerant passage;
A control device for controlling the rotation of the compressor,
The first refrigerant is vaporized by being heated by the heat of the object to be cooled in the refrigerant chamber, and is cooled and liquefied by the atmosphere in the first condenser.
The cooling device, wherein the second refrigerant is liquefied by being cooled by a second condenser, is expanded through the expansion valve, and is vaporized in a heat exchanger. The cooling device according to claim 1, wherein
And a sensor for detecting the temperature of the heat absorbing member.
The controller is
When the temperature of the heat absorbing member detected by the sensor is equal to or lower than a preset temperature, the compressor is stopped, and when the temperature of the heat absorbing member is higher than the set temperature, the compressor is in an operating state. A cooling device having a function of The cooling device according to claim 2, wherein
The controller is
A function of gradually increasing the rotational speed of the compressor when the temperature of the heat absorbing member detected by the sensor is higher than the set temperature;
The cooling device having a function of gradually decreasing the rotational speed of the compressor when the temperature of the heat absorbing member detected by the sensor is equal to or lower than the set temperature. The cooling device according to any one of claims 1 to 3,
The cooling apparatus further comprises a fan that blows air to the second refrigerant passage. In the cooling device according to any one of claims 1 to 4,
The cooling device, wherein the first refrigerant and the second refrigerant are alternative chlorofluorocarbons.

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