JPH0517535Y2 - - Google Patents

Description

[Detailed Description of the Invention] [Industrial Application Field] The present invention relates to a brine temperature control device that controls brine over a wide temperature range.

[Conventional technology] Conventionally, the temperature of brine supplied to the load was set at -30
Control over a wide temperature range of ~80°C is performed by starting or stopping the refrigerator and heating with a heater.

FIG. 3 shows an example of a known brine temperature control device, in which the refrigerator 1 is constructed by sequentially connecting a compressor 4, a condenser 5, an expansion valve 6, and a heat exchanger 7 in series. When controlling the temperature over a wide temperature range, a plurality of the refrigerators 1 are installed in parallel.

On the other hand, the brine circulation circuit 2 is constructed by sequentially connecting a brine tank 11, a pump 12, and a load 13 in series.
... and a heater 14 are installed, and the refrigerator 1,...
The temperature sensor 1 detects the temperature of the brine in the tank 11.
It is controlled by a temperature controller 16 operated by 5.

In the above-mentioned known temperature control device, when controlling the temperature of brine to 80° C., for example, only one refrigerator 1 is operated as a cooling source, and the brine in the tank 11 cooled by this is heated. It is heated and controlled at 14.

In addition, when controlling the brine temperature to 30°C, operate two refrigerators 1 and 1 as a cooling source,
When heating and controlling the brine temperature with the heater 14 to -30°C, all the refrigerators 1, . . .
The brine is cooled to a level higher than the heat input from the load 13 by operating the brine, and then heated by the heater 14 for control.

As mentioned above, brine temperature control in a known temperature control device involves continuously operating a plurality of refrigerators 1, . . . to control the brine temperature. Temperature control by starting and stopping has a limit in accuracy, and in order to increase the accuracy, it is necessary to cool the device to a temperature higher than the required temperature and then heat it with the heater 14, which causes a problem in that a lot of energy is wasted.

[Problem to be solved by the invention] The problem to be solved by the invention is to provide a brine temperature control device that is capable of more precise control over a wide temperature range than general commercially available devices, and that consumes less energy. It's about doing.

[Means for Solving the Problems] In order to solve the above problems, the present invention provides a compressor,
It is equipped with a refrigerator in which a condenser, an expansion valve, and a heat exchanger are connected in series, and a brine circulation circuit in which a tank, a pump, and a load are connected in series, and the temperature of the brine in the tank is set in the tank. In the brine temperature control device, the temperature control device branches from the discharge side of the pump and connects a solenoid valve and the heat exchanger. and a temperature controller that opens the solenoid valve when the temperature of the brine in the tank is higher than a set temperature range and energizes the heater when it is lower than the set temperature range. It is characterized by having the following.

[Function] When the temperature of the brine in the tank is higher than the set temperature range of the temperature controller, the temperature controller opens the solenoid valve, and the brine flowing through the cooling channel is cooled by the heat exchanger, and then the brine is cooled in the tank. If the temperature is lower than the set temperature range of the temperature control device, the temperature of the brine in the tank can be maintained within the set temperature range of the temperature control device by closing the solenoid valve and heating it with a heater. .

The brine is cooled by the cooling channel and heated by the heater selectively depending on the temperature of the brine relative to the set temperature range of the temperature control device. Energy consumption can be significantly reduced compared to control, and temperature control is more accurate.

Furthermore, by selectively cooling and heating the brine, it is possible to control the temperature over a wide range.

[Embodiment] FIG. 1 shows an embodiment of the present invention, and this brine temperature control device includes a refrigerator 20 and brine circulation circuits 40 and 40a.

The refrigerator 20 includes a compressor 21, a condenser 22,
Pressure receiver 23, temperature type expansion valve 24, heat exchanger 25,
A refrigerant circuit 20a in which 25a are sequentially connected in series,
The hot gas compressed by the compressor 21 is transferred to the heat exchanger 2
The opening of the temperature-type expansion valve 24 is controlled by a temperature sensor 29, and the operation of the compressor 21 is controlled by a high/low pressure switch 30. The flow rate of the hot gas flowing through each is controlled by a capacity adjustment valve 28.

The circulation circuit 40 includes a tank 41, a pump 42
and a main flow path 44 in which a load 43 is sequentially connected in series.
and a cooling passage 45 that branches from the discharge side of the pump 42 and returns to the tank 41, and the cooling passage 45 has heat exchanged with the refrigerant of the refrigerator 20 in the solenoid valve 46 and the heat exchanger 25. A replacement part 47 is provided in series.

The tank 41 has a heater 5 for heating brine.
0,51, opening and closing of the solenoid valve 46 and heater 5
0 and 51 are controlled by a temperature controller 53 that operates based on a signal from a temperature sensor 52 that detects the temperature of the brine in the tank 41. If the temperature is higher than the set temperature of 53, the solenoid valve 46
is opened and the heaters 50 and 51 are de-energized to cool the brine.If the temperature is lower than the set temperature, the solenoid valve 46 is closed and the heater 5 is de-energized.
When the temperature is within the set temperature range, the electromagnetic valve 46 and the heaters 50, 51 are de-energized to stop raising and lowering the temperature of the brine.

On the other hand, the circulation circuit 40a has a temperature controller 53
The brine setting temperature range according to a is the circulating circuit 40.
Since it has the same configuration as the circulation circuit 40 except that it is configured as a low temperature circulation circuit whose temperature is lower than the setting range of , a detailed explanation will be omitted by adding the symbol a to the reference numerals of the same parts. Note that reference numerals 48 and 48a in FIG. 1 are relief valves.

Next, the operation of the above embodiment will be described.

In the refrigerator 20, the operation of the compressor 21 is protected by a high/low pressure switch 30, and the hot gas flowing through the hot gas passage 27 is controlled by a capacity control valve 28 to prevent the brine from freezing in the heat exchanger 25a on the low temperature side. Adjusted by. In addition, heat exchanger 2
The evaporation temperature 5a is controlled by controlling the opening degree of the thermostatic expansion valve 24 using the temperature sensor 29.

On the other hand, the brine flowing through the main flow path 44 of the circulation circuit 40 receives or radiates heat in the load 43 and returns to the tank 41, and the temperature sensor 52 detects the changing temperature of the brine in the tank 41.

In the temperature controller 53, the temperature sensor 5
The temperature of the brine in the tank 41 detected by 2 is
When the temperature is higher than the set temperature range of the controller 53, the electromagnetic valve 46 is opened, and the brine flowing through the cooling channel 45 is cooled in the heat exchange section 47 and then returned to the tank 41 to lower the temperature of the brine in the tank 41. The temperature is lowered to within the set temperature range, and when the temperature is lower than the set temperature range, the solenoid valve 46 is closed and the heater 5 is turned off.
By energizing one or both of 0 and 51, the tank 41
The temperature of the brine inside the brine is raised to within the set temperature range, and when the temperature is within the set temperature range, electricity is cut off to the solenoid valve 46 and the heaters 50 and 51 to stop raising and lowering the temperature of the brine.

Further, in the circulation circuit 40a, the temperature of the brine in the tank 41a is maintained within the temperature range set by the temperature controller 53a, which is lower than the temperature range set by the temperature controller 53, by the same operation as described above.

FIG. 2 shows the experimental results of the temperature control device in the above embodiment. When the temperature of the brine in the tanks 41, 41a rose by 0.4°C from the set temperature, the solenoid valves 46, 46a were opened, and the temperature decreased by 0.1°C. When closed, the brine temperature is 0.4℃ higher than the set temperature
When the temperature drops, the heaters 50, 51, 50a, 51
The temperature of the brine in the tanks 41, 41a can be controlled with high accuracy to ±0.5°C or more of the set temperature by energizing the heater a and cutting off the power to the heater when the temperature drops by 0.35°C from the set temperature. can.

Note that general commercially available devices typically have an accuracy of ±1.0°C.

Furthermore, in the above embodiment, the brine is selectively cooled or heated based on the temperature difference between the temperature of the brine in the tanks 41, 41a and the set temperature of the temperature controllers 53, 53a, and the brine is selectively cooled or heated depending on the operating conditions. Since there is no need to heat or cool the brine, energy consumption is significantly reduced compared to conventional temperature control devices that heat brine that has been cooled more than necessary using a heater to raise the temperature to a predetermined set temperature. be able to.

For example, if the ambient temperature of the refrigerator changes within a temperature range of 0.4℃, if the brine temperature setting is 20℃, when the ambient temperature is below 20℃, the brine will be on the heat radiation side, so it will be controlled by the heater and temperature is 20
When the temperature is above ℃, the brine becomes the heat receiving side, so by controlling the temperature using the solenoid valve 45, it is possible to respond to a wide range of changes in the ambient temperature.
This allows the refrigerator 21 to be operated continuously.

[Effect of the invention] The brine temperature control device of the invention controls the opening and closing of the solenoid valve in the cooling channel and the control of the heater depending on the temperature difference between the set temperature range of the temperature controller and the temperature of the brine in the tank. By selectively operating the energization to cool or heat the brine, the temperature of the brine in the tank is maintained within the set temperature of the temperature controller, which not only significantly reduces energy consumption but also achieves high accuracy. The temperature can be controlled with.

Furthermore, since the brine is selectively cooled and heated, the brine can be controlled over a wide temperature range.

[Brief explanation of the drawing]

FIG. 1 is a block diagram of an embodiment of the present invention, FIG. 2 is a diagram of experimental results of temperature control, and FIG. 3 is a block diagram of a known brine temperature control device. 20... Refrigerator, 21... Compressor, 22... Condenser, 24... Expansion valve, 25... Heat exchanger, 40
... Circulation circuit, 41 ... Tank, 42 ... Pump, 43 ... Load, 45 ... Cooling channel, 46 ...
Solenoid valve, 50, 51... heater, 53... temperature controller.

Claims (1)

[Claims for Utility Model Registration] A refrigerator comprising a compressor, a condenser, an expansion valve, and a heat exchanger connected in series, and a brine circulation circuit in which a tank, a pump, and a load are connected in series,
A brine temperature control device that controls the temperature of brine in the tank to a predetermined temperature range by heating and cooling the temperature of brine in the tank using a heater provided in the tank and the heat exchanger, wherein the temperature control device controls the temperature of the brine in the pump. If the temperature of the brine in the tank is higher than the set temperature range, the solenoid valve is opened and the cooling flow path returns to the tank through the solenoid valve and the heat exchanger. A brine temperature control device comprising: a temperature controller that energizes the heater when the temperature is low.