JPS5941748A - Cooling device - Google Patents

Abstract

(57) [Summary] This bulletin contains application data before electronic filing, so abstract data is not recorded.

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a cooling device such as a refrigerator having a plurality of cold storage chambers having different temperatures.

Conventionally, the system in which high-temperature and low-temperature compartments are cooled by a single refrigeration unit is typically seen in cooling systems such as household refrigerator-freezers, and basically the cooling system shown in Figure 1 Adopt the system ℃℃・ru.

FIG. 1 is a schematic diagram showing the configuration of a conventional cooling device, in which 1 is a compressor, 2 is a condenser, 3 is a first capillary tube, 4 is a high-temperature evaporator,
7 is a second capillary tube, 8 is a low temperature evaporator, 10 is a high temperature chamber, 11
12 is a low-temperature refrigerator and an accumulator.

Next, we will explain the operation.

In FIG. 19, the air is discharged from the compressor 1, and the condenser
The liquefied refrigerant liquid is depressurized in the first capillary tube 3 and partially evaporated in the high-temperature evaporator 4 disposed in the high-temperature refrigerator 10, at which time it performs a cooling effect in the high-temperature refrigerator 10. The gas-liquid two-phase refrigerant liquid that exits the high-temperature evaporator 4 is depressurized again in the first capillary tube 3.
The remainder is evaporated in a low-temperature evaporator 8 disposed inside the low-temperature refrigerator 11, and at this time, the low-temperature refrigerator 11 is cooled 1'. The refrigerant liquid exiting the low-temperature evaporator 8 is sucked into the compressor 1 via the accumulator 12. Temperature control in high and low temperature storage 10.11 is high temperature pressure 10. Starting from K, the compressor 1 is driven and stopped by a temperature controller (not shown) disposed in either of the low-temperature refrigerators 11.

In the conventional example with the above configuration, the suction pressure of the compressor 1 depends on the evaporation pressure of the low-temperature evaporator 8.
No matter how high the evaporation pressure of the high-temperature evaporator 4 is, the coefficient of performance of the compressor 1 is extremely poor, and the cooling system is forced to operate inefficiently. Further, as mentioned above, since the temperature inside the refrigerator must be adjusted depending on the temperature inside either the high or low temperature refrigerator 10 or 110, there is a drawback that the temperature inside the other refrigerator is left to its own devices.

On the other hand, in order to enable independent control of the internal temperature of each refrigerator, one trap and one evaporator are used, so that the high temperature pressure chamber 10 can control the internal temperature by damper control, and the low temperature chamber 1
Temperature 1 is the drive of compressor 1.

Cooling systems that perform shutdown operations have also become common in household refrigerators and the like in recent years. Although this method allows for independent control of the temperature inside both chambers, the evaporation temperature of the evaporator still depends on the temperature of the low-temperature chamber 11, so as described for the conventional example, the efficiency of the cooling system is extremely low. It's still bad. Also, when using this method,
The cooling surface temperature of the evaporator that cools the high temperature pressure 10 is the low temperature storage 11
As a result, the inside of the high-temperature storage 10 becomes excessively dry, and the amount of frost on the evaporator becomes large, which requires frequent pig boxes.

This invention was made to improve the various drawbacks of the above-mentioned conventional devices, and is intended to improve (change) the cooling system of conventional home refrigerators and the like.

This invention will be explained below.

FIG. 2 is a schematic diagram showing one embodiment of the present invention. In this figure, 5 and 6 are the first . A second electromagnetic valve, T is a second capillary tube, and a low temperature evaporator 8 disposed in the low temperature storage 11
The refrigerant pipe is disposed in a refrigerant piping path between the outlet of the first capillary tube 3 and the second electromagnetic valve 6 .

Reference numeral 9 is a check valve, and the other parts are the same as in FIG.

The embodiment of FIG. 2 resembles a conventional refrigeration system with parallel evaporators, but is fundamentally different. That is, first, there is no pressure adjustment section provided in the conventional parallel cooling system for matching the evaporation pressures of the different generators 4 and 8 to the same suction pressure after the high temperature evaporator 4 of the present invention. . In other words, the characteristic operation of this invention is 4. '8IC, is that the refrigerant liquid does not flow at the same time, and in more detail, the second solenoid valve 62, both capillary tubes 3. γ, low temperature evaporator8. A low temperature system constituted by a check valve 9 and a first solenoid valve 5. The specifications of each system in the high-temperature system composed of the first capillary tube 3° and the high-temperature evaporator 4 are the evaporation temperature (pressure) of the generators 4 and 8 in combination with the compression 4s1, the heat source side of the condenser 2, and each system alone. However, for example, the temperature of the low temperature evaporator 8 is set to 130°C, and the temperature of the high temperature evaporator 4 is set to 0°C.

In other words, the present invention operates each of the low temperature and high temperature systems independently, in other words, the condenser 2 distributes the refrigerant liquid at the destination to the generators 4 and 8 in time series, and cools the high temperature pressure 10. By maintaining the evaporation temperature (pressure) of the high-temperature evaporator 4 at a high level, the coefficient of performance of the compressor 1 is improved and the operating efficiency of the refrigeration system is improved.

FIG. 3 is a block diagram of the operation control circuit. In FIG. 3, 21.22 is the high temperature pressure 10. Temperature detection sensors disposed in each of the low-temperature refrigerators 11, 23 and 24 a temperature controller, 25 an AND circuit such as an AND gate established by the off signal of the temperature controller 23 and the on signal of the temperature controller 240; 26 is a logical sum circuit such as an OR gate established by either the output of the logical product circuit 25 and the ON signal of the temperature controller 230, and 1, 5.6 is a compressor as in FIG.

They are a first solenoid valve and a second solenoid valve.

Next, the operation of the embodiment shown in FIG. 2 will be explained with reference to the block diagram of the operation control circuit shown in FIG. 3.

The internal temperatures of both chambers detected at regular intervals by the temperature detection sensors 21 and 22 are input to temperature controllers 23 and 24. When the temperature inside the high temperature 10 is high, the temperature controller 23 outputs an on signal to the first electromagnetic valve 5 and the compressor 1 via the OR circuit 26 to operate both.

When this is done, the refrigerant liquid evaporates in the high-temperature evaporator 4 in the high-temperature device 10, thereby performing a cooling effect on the high-temperature device 10.

At this time, the temperature inside the low-temperature refrigerator 11 becomes high, and even if an ON signal is output from the temperature controller 24, the AND circuit 25 is not established as shown in FIG. 3, so the second solenoid valve 6 does not open. The cold storage 11 is not cooled. However, when the high temperature 10 is cooled and reaches a predetermined value, the temperature controller 23 outputs an off signal and closes the first solenoid valve 5. The compressor 1 is driven for a certain period of time (several seconds) and the refrigerant liquid is stored in the high-temperature evaporator 4. If an off signal is output from the temperature controller 24 at that time, the compressor 1 is stopped. However, at this time, if the temperature inside the low-temperature refrigerator 11 is high and the ON signal is output from the temperature controller 24, the AND circuit 25 is established by this ON signal and the OFF signal from the temperature controller 23, so the OR circuit 26 Compressor 1 by
continues to operate, and the second solenoid valve 6 is also opened by the logical product output, thereby cooling the low-temperature refrigerator 11.

In this way, if the temperature of the high-temperature storage 10 rises above the predetermined value again during the cooling operation of the low-temperature storage 11, the high-temperature storage 10 will be turned on by the ON signal of the temperature controller 23 as described above.
Switches to 0 cooling operation.

If the internal temperatures of both chambers are below a predetermined value, the temperature controller 23.
24 each output an off signal, and the first . The second electromagnetic valves 5 and 6 are closed, and if the cooling operation of the high temperature evaporator 10 is performed at this time, the compressor 1 is stopped after refrigerant liquid is stored in the high temperature evaporator 4 as described above.

Next, the effects of the present invention described above will be explained using specific numerical values using a household refrigerator-freezer as an example.

Normally, the temperature of the low-temperature compartment (freezer) 11 of a household refrigerator-freezer is about -18°C, and in order to monitor the internal temperature, K is -
Evaporation temperatures of 25 to -30°C are required. On the other hand, the temperature of the high temperature room (refrigeration room) 10 is about 3℃, and the evaporation temperature is O
~-5°C is sufficient. Further, the cooling load ratio between the two is about 4:6, and the load on the high temperature (refrigeration room) 10 is larger. In addition, the coefficient of performance of compressor 1, that is, the operating efficiency, is -2
When comparing the apparent onset temperatures of 5 to -30°C and O to -5°C, the latter is about 2 to 2.5 times the former.

In other words, when the embodiment of the present invention explained in FIGS. 2 and 3 is applied to, for example, a household refrigerator-freezer, the
It can be seen that the cooling load of the refrigerator compartment, which accounts for 0%, can be absorbed by 1 degree with the operating efficiency of the compressor 1, which is more than twice that of the conventional system, and a large energy saving effect can be expected. In addition, 10 for high temperature
It is possible to prevent continuous cooling operation only on the high temperature 10 side due to opening of the side door or excessive load.

In the above embodiment, the second solenoid valve 6 is placed in the low temperature system to simplify the explanation, but since the flow resistance of the second capillary tube 7 for low temperatures is significantly larger than that for high temperatures, It is not necessary to insert the second solenoid valve 6.

Further, although the above explanation has been made only for a load having two systems, it goes without saying that the present invention can be applied to loads having more systems.

As explained above, this invention distributes refrigerant liquid to evaporators with different evaporation pressures in chronological order, and gives priority to cooling for high temperatures over cooling for low temperature storage. Operation efficiency can be dramatically improved. In addition, it is possible to independently control the temperature inside each warehouse.
Furthermore, it is possible to optimize the refrigerant flow rate for each operation of the high-temperature system and the low-temperature system, and there are great effects such as eliminating the need for pressure regulating valves and the like. Furthermore, since the cooling for high temperatures is performed at an appropriately high evaporation temperature, there is an advantage that problems such as drying for high temperatures do not occur.

[Brief explanation of the drawing]

Fig. 1 is a schematic diagram showing a conventional cooling device, Fig. 2 is a schematic diagram showing an embodiment of the present invention, and Fig. 3 is a block diagram of an operation control circuit to explain the operation of Fig. 2. be. In the figure, 1 is a compressor, 2 is a condenser, 3 is a first capillary,
4 is a high temperature evaporator, 5 is a first solenoid valve, 6 is a second solenoid valve, T
2 is a second capillary tube, 8 is a low temperature evaporator, 9 is a check valve, 10 is a high temperature chamber, 11 is a low temperature chamber, 12 is an accumulator, 21.2
2 is a temperature detection sensor, 23 and 24 are temperature controllers, 25 is an AND circuit, and 26 is an OR circuit. Note that the same reference numerals in the figures indicate the same or corresponding parts. Agent Nobuo Yuno - (1 other person) Figure 1

Claims (1)

[Claims] A cooling device in which a high-temperature storage and a low-temperature storage are respectively provided with a high-temperature evaporator and a low-temperature evaporator, and the refrigerant liquid from the compressor is passed through the high-temperature evaporator and the low-temperature evaporator through a first capillary tube for cooling. A solenoid valve is arranged downstream of the evaporator, a second capillary is arranged upstream of the low temperature evaporator, and the high temperature evaporator and the solenoid valve are connected in series, and the second capillary and the low temperature evaporator are connected in series. connected in parallel to each other, a temperature detection sensor is provided in each of the high temperature storage and low temperature storage, and a temperature controller is provided for outputting an on signal and an off signal in accordance with the output of these temperature detection sensors, and further The cooling of the high-temperature refrigerator is given priority over the cooling of the low-temperature refrigerator, and when the high-temperature refrigerator is being cooled, an off signal is sent from the temperature controller on the high-temperature refrigerator to close the solenoid valve and the compressor is operated for a predetermined period of time. 1. A cooling device comprising an operation control circuit for driving the high temperature evaporator to store refrigerant liquid in the high temperature evaporator.