JPH06164178A - Cooling apparatus - Google Patents

Abstract

PURPOSE:To provide a cooling apparatus for circulatingly supplying a liquid coolant to an electric apparatus defined as a cooling object mounting heat generating circuit elements with a high packing density and particularly provide a cooling apparatus for controlling an injection temperature of the liquid coolant depending on the environmental conditions of the cooling object. CONSTITUTION:Generation of dew within a cooling object 1 and in a coolant circulating pipe, etc., by detecting temperature and humidity environment of an arranging section 14 of the cooling object with sensors 16, 17, calculating the lower limit value of liquid coolant supply temperature which can prevent generation of dew in the periphery of the liquid coolant circulating system and controlling the liquid coolant supply temperature through adjustment of an opening angle of a control valve 6 of the secondary side piping system with a control circuit 13 depending on the calculated value.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a cooling device which circulates a liquid refrigerant by using as an object to be cooled an electronic device on which heat-generating circuit elements are mounted, and more particularly to a liquid refrigerant depending on environmental conditions of the object to be cooled. The present invention relates to a cooling device that controls the discharge temperature of

[0002]

2. Description of the Related Art FIG. 4 is a diagram showing a configuration example of a conventional cooling device. In the figure, 1 is an object to be cooled, 2 is a secondary discharge piping system, 3 is a secondary return piping system, 4 is a cooling device secondary piping system, 5 is a pump, 6 is a secondary control valve, 7
Is a heat exchanger, 8 is a primary side piping system in a cooling device, 9 is a primary side supply piping, 10 is a primary side return piping, 11 is a secondary side refrigerant discharge temperature sensor, 12 is a secondary side refrigerant return temperature Sensor, 13
Is a control circuit, 14 is a section to be cooled, and 15 is a cooling device.

The conventional cooling device 15 is constructed as described above, and the secondary side refrigerant is supplied to the object to be cooled 1 through the secondary side discharge piping system 2 by the pump 5 and then the secondary side return piping system. It is recovered by the cooling device 15 via 3. The recovered secondary-side refrigerant is cooled by heat exchange with the primary-side refrigerant in the heat exchanger 7, but inside the cooling device 15, the heat generation state of the cooled object 1 is the secondary-side discharge temperature sensor 11 and The return temperature sensor 10 detects a change in the refrigerant temperature, and the control circuit 13 performs signal control of the opening degree of the secondary side control valve 6 according to the detected increase / decrease in the heat generation load, whereby the refrigerant flow rate to the heat exchanger 7 is increased. Was controlled to control the heat exchange capacity, and the secondary side refrigerant discharge temperature was controlled to be constant.

[0004]

In the conventional cooling device, for example, when the temperature and humidity of the section where the object to be cooled is changed, dew condensation is formed around the pipe through which the liquid refrigerant is passed and the circuit elements mounted inside the object to be cooled. It is liable to occur, which has been a cause of deterioration of parts and contact failure of connectors, for example. Therefore, in the above conventional cooling method, in order to prevent the above-mentioned dew condensation, the temperature and humidity environment of the object to be cooled is constantly controlled below the dew point with respect to the liquid refrigerant supply temperature, or the liquid refrigerant supply temperature is relatively high such as 30 ° C. Attempts have been made to prevent dew condensation by means of setting. However, the former environment temperature and humidity control is stricter than general air-conditioning management level, so there is a drawback that an air-conditioning facility dedicated to the section in which the object to be cooled is placed is necessary, and the latter is inside the object to be cooled. Since the reliability of a large number of circuit elements used depends on the temperature, there is a problem that the reliability decreases as the temperature increases.

In the present invention, such a problem is solved,
It has a means for detecting the temperature and humidity environment of the cooled object arrangement section,
The present invention provides a cooling device that controls the discharge temperature of a liquid refrigerant to a minimum temperature within a range allowable for dew condensation prevention in accordance with the change state.

[0006]

In the cooling device according to the present invention, a sensor for detecting the air temperature and relative humidity in the compartment is installed in the object to be cooled arrangement and is stored in advance in the arithmetic circuit in the cooling device. By calculating the refrigerant supply temperature lower limit value that can prevent dew condensation from the saturated vapor pressure curve of air, and receiving the signal as a signal, the control circuit controls the opening of the secondary side control valve to control the heat exchange capacity. The liquid refrigerant discharge temperature is controlled to the lower limit value calculated by the arithmetic circuit. Here, T: ambient temperature t of the object to be cooled disposed compartment detected by the temperature sensor: the liquid coolant supply temperature (° C.) H _R to the object to be cooled: environment relative to the object to be cooled arranged compartments detected by the humidity sensor Humidity (%) P _S (t): Function indicating the saturated vapor pressure of air at temperature t (mmHg) P: If it is the vapor content (mmHg) of the cooling target arrangement section, the liquid refrigerant will flow to the cooling target at temperature t The condition that does not cause dew condensation around the refrigerant circulation part when P is supplied is P _S (t)> P = P _S (T) XH _R Therefore, t = P ⁻¹ _S {P _S (T) XH _R } The temperature t defined by + a (where a is a margin value in consideration of measurement error and refrigerant temperature control accuracy) may be calculated by the arithmetic circuit and transmitted as a signal to the control circuit (see FIG. 3).

Further, a control valve and a constant heating heater are provided in the primary side refrigerant piping system, and the opening of the control valve is controlled to adjust the flow rate of the primary side refrigerant flowing into the heat exchanger to perform heat exchange. As a result of controlling the capacity and adjusting the flow rate of the primary side refrigerant flowing into the heat exchanger, the temperature rise of the primary side refrigerant by the heater is also adjusted, and the primary side refrigerant flowing into the heat exchanger is also adjusted. Is also controllable, and a two-parameter control of heat exchange capacity and temperature realizes a control system capable of widely responding to changes in heat generation conditions of the object to be cooled and environmental conditions of the object to be cooled.

[0008]

In the cooling device according to the present invention, the temperature and humidity environment of the section to be cooled is detected by the sensor, and from this information, the lower limit value of the liquid refrigerant supply temperature that can prevent dew condensation around the liquid refrigerant circulation system in the arithmetic circuit. Is calculated by the method shown in Section 6, and the control circuit adjusts the control valve opening of the secondary side piping system according to the calculated value to control the liquid refrigerant supply temperature, and It becomes possible to prevent the occurrence of dew condensation. Further, by setting the liquid refrigerant supply temperature to the required minimum temperature, it becomes possible to sufficiently secure the reliability of the electronic device which is the object to be cooled.

One control valve and one constant heating heater
The heat exchange capacity is controlled by adjusting the flow rate of the primary side refrigerant flowing into the heat exchanger by controlling the opening of the control valve provided in the secondary side refrigerant piping system. Further, as the effect of adjusting the flow rate of the primary side refrigerant flowing into the heat exchanger, the temperature rise of the primary side refrigerant by the heater can be adjusted, and therefore the heat exchange capacity of the heat exchanger and the supply of the primary side refrigerant to the heat exchanger. Two parameters of temperature can be controlled,
It is possible to realize a control system capable of widely responding to a drastic change in the heat generation condition of the cooled object and the environmental condition of the cooled object.

[0010]

EXAMPLES Example 1. FIG. 1 is a diagram showing an embodiment of a cooling device according to the present invention. In the figure, 1 is an object to be cooled, 2
Is a secondary discharge pipe system, 3 is a secondary return pipe system, 4 is a cooling device secondary pipe system, 5 is a pump, 6 is a secondary control valve, 7 is a heat exchanger, and 8 is a cooling device. Inside primary side piping system, 9 is primary side supply piping, 10 is primary side return piping, 11
Is a secondary side refrigerant discharge temperature sensor, 12 is a secondary side refrigerant return temperature sensor, 13 is a control circuit, 14 is a section to be cooled, and
Reference numeral 15 is a cooling device, 16 is a humidity sensor, 17 is a temperature sensor, and 18 is an arithmetic circuit.

In the cooling device 15 configured as described above, the temperature and humidity environment of the arrangement section 14 of the object to be cooled 1 is detected by the sensors 16 and 17, and from this information, the arithmetic circuit 18 is used to detect the periphery of the liquid refrigerant circulation system. Calculate the lower limit value of the liquid refrigerant supply temperature that can prevent dew condensation in. In FIG. 3, P _S (t) is a saturated vapor pressure curve of air, and shows a partial vapor pressure of contained air in a saturated state at t (° C.). Therefore, in order to prevent the occurrence of dew condensation, it is necessary to always maintain the state of air in the lower region of the saturated vapor pressure curve. In particular, since the temperature of the air around the refrigerant pipe locally becomes equal to the temperature of the refrigerant, the vapor partial pressure P of the air must always be kept below the saturated vapor pressure at the refrigerant supply temperature T (° C). Conversely, when the temperature and humidity environment of air is detected, the refrigerant temperature (air temperature around the refrigerant pipe) must be maintained at a temperature at which the saturated vapor pressure is higher than the vapor partial pressure of the air. This condition is shown as a formula in the dew condensation preventing condition formula shown in FIG. The relative humidity of air is a ratio of the partial vapor pressure of air in a certain state to the saturated vapor pressure at that temperature expressed in (%). When the refrigerant discharge temperature obtained by the dew condensation preventing conditional expression in the arithmetic circuit 18 is transmitted to the control circuit 13 as a signal, the control circuit 13 causes the refrigerant temperature sensors 11 and 12 to operate.
The refrigerant temperature condition detected by the above is compared with the instruction signal value from the arithmetic circuit 18, and a feedback control signal is transmitted to the control valve 6 of the secondary side piping system so that the refrigerant discharge temperature becomes the arithmetic circuit 18 calculated value. The opening degree is adjusted to control the liquid refrigerant supply temperature to the object to be cooled 1. As a result, it becomes possible to prevent the occurrence of dew condensation inside the object to be cooled 1, the refrigerant circulation pipe, and the like. Further, since the liquid refrigerant supply temperature can be set to the required minimum temperature according to the situation, it becomes possible to sufficiently secure the reliability of the cooled object 1 which is an electronic device.

Example 2. FIG. 2 is an internal configuration diagram of a cooling device showing a second embodiment of the liquid refrigerant discharge temperature control method in the cooling device according to the present invention. In the figure, 2 is a secondary side discharge piping system, 3 is a secondary side return piping system, 4 is a cooling system secondary side piping system, 5 is a pump, 7 is a heat exchanger, 8 is a cooling system primary side. Piping system, 9 is a primary supply pipe, 10 is a primary return pipe, 11 is a secondary refrigerant discharge temperature sensor, 12 is a secondary refrigerant return temperature sensor, 13 is a control circuit, 15 is a cooling device, 18 Is an arithmetic circuit, 19 is a primary side control valve, and 20 is a heater.

In the cooling device 15 constructed as described above, the control valve 19 and the constant heating heater 20 are provided.
Is provided in the primary side refrigerant piping system 8, and the control valve 19
The refrigerant discharge temperature can be controlled by adjusting the flow rate of the primary-side refrigerant flowing into the heat exchanger 7 by controlling the opening degree of, and controlling the heat exchange capacity of the heat exchanger 7. Further, as an effect of adjusting the flow rate of the primary side refrigerant by controlling the opening degree of the control valve 19, the temperature rise of the primary side refrigerant by the heater 20 fluctuates as the flow rate increases or decreases, that is, the primary side refrigerant flowing into the heat exchanger 7. Since the temperature can be controlled and the temperature control effect of the secondary side refrigerant temperature can be directly obtained by the fluctuation of the primary side refrigerant temperature, as a result, the heat exchange capacity of the heat exchanger 7 and the heat exchanger 7 1
From the two-parameter control effect of the secondary-side refrigerant supply temperature, it is possible to realize a control system capable of widely responding to both the heat generation condition of the object to be cooled 1 and the drastic change of the environmental condition of the object to be cooled.

[0014]

As described above, in the cooling device according to the present invention, the temperature and humidity environment of the section to be cooled is detected by the sensor, and the information is used to prevent the dew condensation around the liquid refrigerant circulation system in the arithmetic circuit. Calculate the lower limit of liquid refrigerant supply temperature that can be
By controlling the liquid refrigerant supply temperature by adjusting the control valve opening of the secondary side piping system by the control circuit according to this calculated value, it is possible to prevent the occurrence of dew condensation inside the object to be cooled and the refrigerant circulation piping. Becomes Further, by setting the liquid refrigerant supply temperature to the minimum temperature at which dew condensation can be prevented, it becomes possible to sufficiently secure the reliability of the electronic device which is the object to be cooled.

One control valve and one constant heating heater
The heat exchange capacity is controlled by adjusting the flow rate of the primary side refrigerant flowing into the heat exchanger by controlling the opening of the control valve provided in the secondary side refrigerant piping system. Further, as the effect of adjusting the flow rate of the primary side refrigerant flowing into the heat exchanger, the temperature rise of the primary side refrigerant by the heater can be adjusted, and therefore the heat exchange capacity of the heat exchanger and the supply of the primary side refrigerant to the heat exchanger. Two parameters of temperature can be controlled,
It is possible to realize a control system capable of widely responding to a drastic change in the heat generation condition of the cooled object and the environmental condition of the cooled object.

One control valve and one constant heating heater
The heat exchange capacity is controlled by adjusting the flow rate of the primary side refrigerant flowing into the heat exchanger by controlling the opening of the control valve provided in the secondary side refrigerant piping system. further,
As a result of adjusting the flow rate of the primary-side refrigerant flowing into the heat exchanger, the temperature rise of the primary-side refrigerant by the heater can be adjusted, so that the heat exchange capacity of the heat exchanger and
It becomes possible to control two parameters of the secondary side refrigerant supply temperature, and it is possible to realize a control system capable of widely responding to a drastic change in the heat generation condition of the cooled object and the environmental condition of the cooled object.

[Brief description of drawings]

FIG. 1 is a diagram showing a first embodiment of the present invention.

FIG. 2 is an internal configuration diagram of a cooling device showing a second embodiment of the present invention.

FIG. 3 is a diagram showing how to obtain a liquid refrigerant supply temperature allowable lower limit value calculated in an arithmetic circuit of the present invention.

FIG. 4 is a diagram showing a conventional configuration example.

[Explanation of symbols]

 1 Cooled Body 2 Secondary Side Discharge Piping System 3 3rd Side Return Piping System 4 Cooling Device Secondary Side Piping System 5 Pump 6 Secondary Side Control Valve 7 Heat Exchanger 8 Cooling Device Primary Side Piping System 9 1 Secondary supply piping system 10 Primary return piping system 11 Secondary refrigerant discharge temperature sensor 12 Secondary refrigerant return temperature sensor 13 Control circuit 14 Cooled object arrangement section 15 Cooling device 16 Humidity sensor 17 Temperature sensor 18 Arithmetic circuit 19 Primary side control valve 20 Heater

Continuation of front page (51) Int.Cl. ⁵ Identification code Office reference number FI technical display location H01L 23/473

Claims (2)

[Claims] 1. A refrigerant circulation pump, a heat exchanger for exchanging heat between the primary and secondary refrigerants, and a control valve for controlling the flow rate of the refrigerant flowing into the heat exchanger. In a cooling device that circulates a liquid refrigerant as a side refrigerant to an object to be cooled, which is an electronic device, a detection unit that detects the ambient temperature and the relative atmospheric humidity of the object to be cooled, and the data from each of the detection units to the object to be cooled. An arithmetic circuit that obtains the allowable discharge lower limit temperature of the liquid refrigerant that does not cause dew condensation, a temperature sensor installed at the liquid refrigerant discharge / return port, the temperature detected by the temperature sensor, and the calculated value of the arithmetic circuit match. Thus, the cooling device is provided with a control circuit that controls the opening degree of the secondary refrigerant side control valve of the heat exchanger and controls the liquid refrigerant discharge temperature. 2. A secondary circulation system having a refrigerant circulation pump, a heat exchanger for exchanging heat between the primary side and the secondary side refrigerant, and a control valve for controlling the flow rate of the refrigerant flowing into the heat exchanger. In a cooling device that circulates a liquid refrigerant as a side refrigerant to an object to be cooled, which is an electronic device, a detection unit that detects the ambient temperature and the relative atmospheric humidity of the object to be cooled, and the data from each of the detection units to the object to be cooled. An arithmetic circuit for obtaining an allowable lower limit discharge temperature of the liquid refrigerant that does not cause dew condensation, a temperature sensor installed at a discharge / return port of the liquid refrigerant, a control valve and a beater provided on the primary refrigerant side of the heat exchanger. , The opening of the control valve on the primary refrigerant side of the heat exchanger is varied so that the temperature detected by the temperature sensor and the calculated value of the calculation circuit match, and the heat exchanger capacity and the heat exchanger are changed. And a control circuit for controlling the primary refrigerant supply temperature of 1.