JP4999530B2 - Air conditioner - Google Patents

Description

  The present invention relates to an air conditioner, and more particularly, to a refrigerant circuit configuration for promoting supercooling for improving cooling performance by promoting supercooling of a condensate refrigerant.

  FIG. 2 is a refrigerant circuit diagram illustrating a refrigerant circuit configuration of an air conditioner that performs supercooling promotion using a supercooling generation refrigerant circuit, and an increase in supercooling of the condensate refrigerant in the main refrigerant circuit is represented by a supercooling generation refrigerant circuit. Is used to improve the cooling effect. Note that this refrigerant circuit configuration can be applied not only to a general air conditioner but also to a refrigeration apparatus.

  The refrigerant circuit of the air conditioner in FIG. 2 is an example of the refrigerant circuit that is the background of the present invention. In the system having two main refrigerant circuits 1 and 2 and the supercooling generation refrigerant circuit 3, the first main refrigerant circuit is shown. 1 first main refrigerant circuit condenser 5 first subcooling generation evaporator 6 of the supercooling generation refrigerant circuit 3 for supercooling the outlet refrigerant, and second main refrigerant circuit condenser of the second main refrigerant circuit 2 9 The supercooling generation refrigerant circuit 3 for supercooling the outlet refrigerant is connected in parallel with the second supercooling generation evaporator 10, and the superheat degree at the outlet of each of the supercooling generation evaporators 6 and 10 is measured by sensors 151 and 152. And the capacity of each of the supercooling generation expansion valves 141 and 142 is controlled.

  The two main refrigerant circuits 1 and 2 in FIG. 2 decompress and supply the refrigerant to the main refrigerant circuit compressors 4 and 8, the main refrigerant circuit condensers 5 and 9, and the main refrigerant circuit evaporators 7 and 11. The main refrigerant circuit expansion valves 191 and 192 are connected in a ring shape in series for each main refrigerant circuit by refrigerant piping.

  The supercooling generation refrigerant circuit 3 decompresses the refrigerant to the supercooling generation circuit compressor 12, the supercooling generation circuit condenser 13, and the plurality of supercooling generation evaporators 6 and 10 connected in parallel. The supercooling generation expansion valves 141 and 142 and the supercooling generation circuit on-off valves 181 and 182 to be supplied are connected in an annular shape by a refrigerant pipe.

Next, the operation will be described.
In the two main refrigerant circuits 1 and 2 of FIG. 2, the high-temperature and high-pressure refrigerant compressed by the main refrigerant circuit compressors 4 and 8 goes to the main refrigerant circuit condensers 5 and 9 where the blower 20 After being cooled and condensed into liquid by heat exchange with the outside air sent by the subcooling, the supercooling generation evaporators 6 and 10 of the supercooling generation refrigerant circuit 3 further exchange heat with the supercooling heat exchangers 211 and 212. Cooled to increase the degree of supercooling.

  The refrigerant that is condensed and liquefied and has an increased degree of supercooling passes through the main refrigerant circuit expansion valves 191 and 192, becomes low-temperature and low-pressure, goes to the main refrigerant circuit evaporators 7 and 11, and exhibits a refrigeration effect, evaporates, The operation returns to the main refrigerant circuit compressors 4 and 8 as gas. At this time, since the degree of supercooling of the refrigerant is increased by the supercooling heat exchangers 211 and 212, the main refrigerant circuit evaporators 7 and 11 have a large refrigeration effect and performance improvement compared to the case without this. Figured.

  When the supercooling generation refrigerant circuit 3 is performing supercooling generation operation, the supercooling generation circuit on-off valves 181 and 182 are opened.

  At this time, the refrigerant that has been compressed by the supercooling generation circuit compressor 12 and has become high temperature and high pressure goes to the supercooling generation circuit condenser 13 where heat is exchanged with the outside air sent by the blower 20 to cool the refrigerant. It is condensed and liquefied. Thereafter, the temperature becomes low temperature and low pressure through the supercooling generation expansion valves 141 and 142, the supercooling generation circuit on-off valves 181 and 182 go to the supercooling generation evaporators 6 and 10, and the main refrigerant circuits 1 and 2 are overheated. The refrigerant flowing through the cooling heat exchangers 211 and 212 is cooled and evaporated by itself to return to the supercooling generation circuit compressor 12 as a gas.

  In addition, the capacity control of the supercooling generation expansion valves 141 and 142 is performed by detecting the outlet temperature of the supercooling generation evaporators 6 and 10 with the sensors 151 and 152, but it is optimal depending on the outside air condition and the air conditioning load condition. In order to perform a supercooling generation operation, the supercooling generation circuit on-off valves 181 and 182 correspond to the main refrigerant circuits 1 and 2 of the supercooling generation refrigerant circuit 3 as the main refrigerant circuit is turned on / off. A mechanism for turning on and off the refrigerant supply to the evaporators 6 and 10 is required.

  In the air conditioner in this case, since the main refrigerant circuits 1 and 2 are two circuits, two of the supercooling generation evaporators 6 and 10 of the supercooling generation refrigerant circuit 3 are connected in parallel. As the number of circuits increases, the same number of supercooling generation expansion valves and supercooling generation circuit opening / closing valves as the number of supercooling generation evaporators are required, which complicates air-conditioning operation control, increases costs, and increases the equipment dimensions. It gets bigger.

  In the air conditioner described above, there is an effect of improving the air conditioning performance of the main refrigerant circuit, but when a plurality of main refrigerant circuits are required, the same number of supercooling expansion expansion valves and supercooling generation circuits as the main refrigerant circuit are required. On-off valves are required, and air-conditioning operation control becomes more complicated, and the cost is high, so that productivity and compactness are not sufficient.

  The present invention has been made to solve such a problem, and even when a plurality of main refrigerant circuits are required, the same number of supercooling expansion expansion valves and supercooling generation circuits as the main refrigerant circuits are provided. It is an object of the present invention to provide an air conditioner that is simple in air-conditioning operation, compact, and has good productivity without requiring an on-off valve.

An air conditioner according to the present invention includes a plurality of main refrigerant circuits configured such that at least a compressor, a condenser, a supercooling heat exchanger, a main expansion valve, and an evaporator are connected in an annular shape, and the plurality of supercooling circuits. A plurality of supercooling generation evaporators for cooling each of the heat exchangers, a supercooling generation circuit compressor, a supercooling generation circuit condenser, and a supercooling generation refrigerant circuit including an expansion valve for supercooling generation The air conditioner has a plurality of main refrigerant circuit heat exchangers provided corresponding to each of the evaporators of the plurality of main refrigerant circuits, and including a plurality of main refrigerant circuit heat exchangers that extract cold heat from the evaporators. exchanger is passed through the cold water in series are connected in series through a pipe, the plurality of supercooling generating evaporator are connected in series, the last stage of the supercooling generating evaporator superheat of the refrigerant at the outlet To control the capacity of the expansion valve for generating the supercooling. It is intended.
Further, the air conditioner according to the present invention includes a supercooling direction from a supercooling heat exchanger of each of the plurality of main refrigerant circuits to the evaporator, and a supercooling generation evaporator of the supercooling generation refrigerant circuit. The direction of the refrigerant flowing to the generator circuit compressor is the same direction.

According to the present invention, in an air conditioner having a supercooling generation refrigerant circuit that increases the supercooling of the liquid refrigerant at the outlet of each condenser having a plurality of main refrigerant circuits in a circuit separate from the main body and increases the efficiency, The cooling generator evaporators are connected in series, and the capacity of the expansion valve for supercooling generation is controlled by the degree of superheat of the refrigerant at the outlet of the final stage supercooling generator evaporator. Even if a main refrigerant circuit that stops operation is generated, the refrigerant for the supercooling generation refrigerant circuit only passes through the corresponding supercooling generation evaporator, and the on / off valve for the supercooling generation circuit is not required. Since the supercooling generation expansion valve can be configured as a single unit, air conditioning operation control is simple, and a compact and highly productive air conditioner can be obtained.
In the present invention, and passed through cold water in series heat exchangers for a plurality of main refrigerant circuit are connected in series through a pipe, the evaporation temperature of the evaporator of the main refrigerant circuit in accordance with the cold water temperature raised, it can be efficiently heat exchanger, since it is possible in even a single configuration controller for controlling collectively heat exchange in each of the heat exchanger main refrigerant circuit, a compact air conditioner be able to.
Further, in the present invention, in the plurality of main refrigerant circuits, the direction of the refrigerant flowing from each supercooling heat exchanger to the evaporator, and in the supercooling generation refrigerant circuit, from the supercooling generation evaporator to the supercooling generation circuit compressor By making the direction of the refrigerant flowing to the same direction efficiently evaporate the refrigerant flowing to the supercooling generation evaporator, and further cooling the refrigerant flowing there in the supercooling heat exchanger of the main refrigerant circuit, The degree of supercooling can be increased.

  FIG. 1 is a refrigerant circuit diagram of a refrigerant circuit configuration of an air conditioner according to an embodiment of the present invention. Here, a basic system configuration is shown, and an example composed of two main refrigerant circuits is shown.

  The refrigerant circuit configuration of the air conditioner according to the present embodiment is composed of a system having two main refrigerant circuits 1 and 2 and a supercooling generation refrigerant circuit 3, and the first main refrigerant of the first main refrigerant circuit 1. The first subcooling generating evaporator 6 of the subcooling generating refrigerant circuit 3 that supercools the refrigerant at the outlet of the circuit condenser 5 and the refrigerant of the second main refrigerant circuit condenser 9 outlet of the second main refrigerant circuit 2 are supercooled. The second supercooling generation evaporator 10 of the supercooling generation refrigerant circuit 3 to be connected is connected in series, and the degree of superheat of the refrigerant at the outlet of the second supercooling generation evaporator 10 is detected by the sensor 15 to generate supercooling. The capacity of the expansion valve 14 is controlled. In addition, control of each part including control of this expansion valve 14 for supercooling production | generation is made | formed by the control apparatus (for example, comprised with a microcomputer) which is not shown in figure.

  The two main refrigerant circuits 1 and 2 of this embodiment include accumulators 4a and 8a, main refrigerant circuit compressors 4 and 8, four-way switching valves 16 and 17 (here, switched to the cooling side), main refrigerant The main refrigerant circuit expansion valves 191 and 192 for supplying the refrigerant to the circuit condensers 5 and 9 and the main refrigerant circuit evaporators 7 and 11 by decompressing the refrigerant are serially connected to each main refrigerant circuit 1 and 2 by a refrigerant pipe. Are connected in a ring.

  The supercooling generation refrigerant circuit 3 includes a supercooling generation circuit compressor 12, a supercooling generation circuit condenser 13, a supercooling generation evaporator 6 connected in series, and a supercooling generation evaporator 10. All of the expansion valves 14 for generating supercooling supplied under reduced pressure are connected in series with a refrigerant pipe.

Next, the operation will be described.
In the two main refrigerant circuits 1 and 2 of the present embodiment, the high-temperature and high-pressure refrigerant compressed by the main refrigerant circuit compressors 4 and 8 goes to the main refrigerant circuit condensers 5 and 9, where the blower After being cooled and condensed into liquid by heat exchange with the outside air sent by 20, further heat exchange is performed by the supercooling heat exchangers 211 and 212 by the supercooling production evaporators 6 and 10 of the supercooling production refrigerant circuit 3. Cooled to increase the degree of supercooling.

  The refrigerants in the main refrigerant circuits 1 and 2 that have been condensed and liquefied and have increased the degree of supercooling pass through the main refrigerant circuit expansion valves 191 and 192, enter a low-temperature and low-pressure state, go to the main refrigerant circuit evaporators 7 and 11 and are frozen. The operation becomes effective, evaporates, becomes gas, and returns to the main refrigerant circuit compressors 4 and 8 via the accumulators 4a and 8a. At this time, since the degree of supercooling of the refrigerant is increased by the supercooling heat exchangers 211 and 212, the main refrigerant circuit evaporators 7 and 11 can obtain a large refrigeration effect and improve performance compared to the case without this. Is planned.

  When the supercooling generation refrigerant circuit 3 is performing supercooling generation operation, the supercooling generation expansion valve 14 controls the refrigerant flow rate. At this time, the refrigerant that has been compressed by the supercooling generation circuit compressor 12 and has become high temperature and high pressure goes to the supercooling generation circuit condenser 13 where heat is exchanged with the outside air sent by the blower 20 to cool the refrigerant. It is condensed and liquefied.

  Thereafter, the refrigerant passes through the supercooling generation expansion valve 14 to be in a low temperature and low pressure state, and goes to the supercooling generation evaporator 6 and the supercooling generation evaporator 10 connected in series. The refrigerant flowing through the supercooling heat exchangers 211 and 212 is cooled and evaporated by itself to return to the supercooling generation circuit compressor 12 as a gas.

  The flow rate control of the refrigerant flowing through the supercooling generation expansion valve 14 is performed by detecting the outlet temperature of the supercooling generation evaporator 10 with the sensor 15.

  During these operations, for example, when the load on the second main refrigerant circuit 2 is reduced and the flow rate of the refrigerant flowing through the main refrigerant circuit 2 is reduced or stopped, the second main refrigerant circuit evaporator 11 is used. The flow rate of the refrigerant flowing through is also reduced or stopped. At this time, in the second subcooling generation evaporator 10 of the subcooling generation refrigerant circuit 3, the amount of heat exchange with the second subcooling heat exchanger 212 is reduced or no heat exchange occurs, 2 The refrigerant at the outlet of the supercooling generation evaporator 10 is in a liquid state. However, the sensor 15 attached to the outlet of the second supercooling generation evaporator 10 detects that the refrigerant is in the liquid state, and the supercooling is performed. The production expansion valve 14 is throttled to control the refrigerant flow rate to be appropriate for such an operation state.

  In the example of FIG. 2 described above, cold water flows in parallel with respect to both the first main refrigerant circuit heat exchanger 221 and the second main refrigerant circuit heat exchanger 222 that extract cold heat. Alternatively, it is possible to adopt a series configuration in which cold water returning from the load side is first introduced into the first main refrigerant circuit heat exchanger 221 and then flowed to the second main refrigerant circuit heat exchanger 222. By adopting such a configuration that allows water to flow in series, the temperature of the water flowing through the first main refrigerant circuit heat exchanger 221 is higher than that in the case of flowing water in parallel as shown in FIG. The refrigerant evaporating temperature of the first main refrigerant circuit heat exchanger 221 is also higher than in the case of FIG. 2, and the efficiency in the first main refrigerant circuit 1 is improved.

  Further, in each main refrigerant circuit 1, 2, the direction of the refrigerant flowing to each supercooling heat exchanger 211, 212 and each supercooling generation evaporator 6, 10 connected in series in the supercooling generation refrigerant circuit 3. It is good also as a structure which makes the direction of the refrigerant | coolant which flows into the same direction.

  In this way, each of the supercooling generation evaporators 6 and 10 is an evaporator that takes into account the temperature drop of the refrigerant due to pressure loss during evaporation, and therefore can be operated efficiently in the supercooling generation refrigerant circuit 3.

  As described above, in the present embodiment, for a system having a plurality of main refrigerant circuits, the main refrigerant circuits 1 and 2 of the supercooling generation refrigerant circuit 3 correspond to the on / off of the main refrigerant circuits 1 and 2. Thus, stable operation can be realized without requiring a mechanism for turning on / off the refrigerant supply to each of the supercooling generation evaporators 6, 7.

  Further, as in the refrigerant circuit of FIG. 2, the same number of supercooling generation expansion valves (141, 142) and supercooling generation circuit opening / closing valves (181, 182) as the supercooling generation evaporators 6, 7 are required. Compared to the air conditioner, the air conditioning operation control is simplified in the present embodiment, the cost can be suppressed, and the equipment dimensions can be made compact.

  The main refrigerant circuit evaporators 7 and 11 of the main refrigerant circuits 1 and 2 may be refrigerant-to-water heat exchangers or refrigerant-to-air heat exchangers, and the main refrigerant circuits 1 and 2 are limited to the illustrated circuits. Needless to say, other devices such as an oil separator, a liquid receiver, a dryer, and a strainer may be installed.

  In addition, the supercooling generation refrigerant circuit 3 is not limited to the illustrated circuit, and it is needless to say that other components such as an oil separator, a liquid receiver, a dryer, and a strainer may be installed.

  In addition, in the example of FIG. 1, an example in which two main refrigerant circuits and two supercooling generation evaporators are installed is illustrated, but the present invention is not limited thereto, It goes without saying that the number of supercooling generating evaporators may be changed according to the supercooling generating refrigerant circuit.

It is a refrigerant circuit figure which shows the refrigerant circuit structure of the air conditioning apparatus which concerns on one Embodiment of this invention. It is a refrigerant circuit diagram which shows the refrigerant circuit structure of the air conditioning apparatus used as the background of this invention.

Explanation of symbols

  1: first main refrigerant circuit, 2: second main refrigerant circuit, 3: supercooling generation refrigerant circuit, 4: compressor for first main refrigerant circuit, 5: condenser for first main refrigerant circuit, 6: first Supercooling generator evaporator, 7: First main refrigerant circuit evaporator, 8: Second main refrigerant circuit compressor, 9: Second main refrigerant circuit condenser, 10: Second subcooling generator evaporator 11: evaporator for second main refrigerant circuit, 12: compressor for supercooling generation circuit, 13: condenser for supercooling generation circuit, 14: expansion valve for supercooling generation, 141: expansion for first supercooling generation Valve, 142: second supercooling generation expansion valve, 151, 152: sensor, 16: first main refrigerant circuit four-way switching valve, 17: second main refrigerant circuit four-way switching valve, 181: first subcooling generation On-off valve for circuit, 182: On-off valve for second subcooling generation circuit, 191: Expansion valve for first main refrigerant circuit, 192: Expansion for second main refrigerant circuit Valve: 20: Blower, 211: First heat exchanger for subcooling, 212: Heat exchanger for second subcooling, 221: Heat exchanger for first main refrigerant circuit, 222: Heat exchange for second main refrigerant circuit vessel.

Claims (2)

A plurality of main refrigerant circuits configured such that at least a compressor, a condenser, a supercooling heat exchanger, a main expansion valve, and an evaporator are connected in a ring shape;
Subcooling provided with a plurality of supercooling generation evaporators, a supercooling generation circuit compressor, a supercooling generation circuit condenser, and a supercooling generation expansion valve for cooling each of the plurality of subcooling heat exchangers In an air conditioner having a generated refrigerant circuit,
Provided corresponding to each evaporator of the plurality of main refrigerant circuits, comprising a plurality of main refrigerant circuit heat exchangers for taking out cold heat from the evaporator,
The plurality of main refrigerant circuit heat exchangers are connected in series via a pipe to pass cold water in series,
Wherein the plurality of supercooling generating evaporator are connected in series,
An air conditioner that controls the capacity of an expansion valve for supercooling generation according to the degree of superheat of the refrigerant at the outlet of the final stage supercooling generation evaporator. The direction of the refrigerant flowing from each supercooling heat exchanger of the plurality of main refrigerant circuits to the evaporator, and the direction of the refrigerant flowing from the supercooling generation evaporator of the supercooling generation refrigerant circuit to the supercooling generation circuit compressor The air conditioner according to claim 1 , wherein the air conditioners are in the same direction.

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