JPWO2013084432A1 - Air conditioner and refrigeration cycle apparatus - Google Patents

Abstract

  The refrigerant flow during the defrosting operation of the outdoor heat exchanger is configured in the same direction as the refrigerant flow during the heating operation, and the outdoor heat exchanger includes a plurality of rows of heat exchangers having a plurality of refrigerant flow paths. The plurality of rows of heat exchangers are provided with a refrigerant flow path inlet in an area on the windward side of the air flow and a refrigerant flow path outlet in another area during heating operation. Is connected so that the number of refrigerant channels increases from the inlet of the refrigerant channel toward the outlet of the refrigerant channel, and the number of refrigerant channels in the inlet region of the refrigerant channel is the same as the refrigerant flow rate in other regions. The number is less than the number of roads.

Description

  The present invention relates to an air conditioner and a refrigeration cycle apparatus. In particular, the present invention relates to an outdoor heat exchanger used in an air conditioner, and a refrigeration cycle apparatus including a switching mechanism for flowing a refrigerant to an auxiliary heat exchanger for melting frost attached to the outdoor heat exchanger.

  An outdoor heat exchanger used in a conventional air conditioner is configured to have high performance when used in either an evaporator or a condenser. When this conventional outdoor heat exchanger is used as an evaporator, it is a refrigerant flow path with a low pressure loss, and when it is used as a condenser, it is a refrigerant flow path that is easy to take a subcool on the outlet side (for example, , See Patent Document 1).

  FIG. 11 is a diagram illustrating a refrigerant flow path of an outdoor heat exchanger of a conventional air conditioner. In FIG. 11, the refrigerant flow path of the outdoor heat exchanger has a refrigerant outlet side during heating operation (inlet side during cooling operation) 100a1, 100b1, 100d1, 100e1 on the leeward side, and a refrigerant inlet side during heating operation on the leeward side. (Exit side during cooling operation) 100c1 and 100f1. In addition, the refrigerant outlet side 100a1, 100b1, 100d1, 100e1 of the refrigerant outlet side during the heating operation (inlet side during the cooling operation) has four systems consisting of 100a, 100b, 100d, 100e. Furthermore, the refrigerant flow paths on the refrigerant inlet side during heating operation (outlet side during cooling operation) 100c and 100f are configured by two systems consisting of 100c and 100f. As described above, during the heating operation, the number of refrigerant flow paths is larger on the outlet side than on the inlet side.

  As a refrigerant flow path of an outdoor heat exchanger of a conventional air conditioner, there is a refrigerant flow path as shown in FIG. In FIG. 12, as the refrigerant flow path of the outdoor heat exchanger, the refrigerant flows from the lowermost step part 110 on the windward side of the outdoor heat exchanger during the heating operation. Then, after a plurality of heat transfer tubes are circulated in one system, they are divided into four channels through the refrigerant channel inlets 110a1, 110b1, 110c1, and 110d1 via the top of the outdoor heat exchanger. Then, the refrigerant flows out from the leeward refrigerant passage outlets 110a2, 110b2, 110c2, and 110d2.

  Conventionally, during heating operation using a heat pump air conditioner, when the outdoor heat exchanger is frosted, defrosting is performed by switching the four-way valve from the heating cycle to the cooling cycle. In this defrosting method, although the indoor fan stops, there is a disadvantage that the cool air is gradually discharged from the indoor unit and the feeling of heating is lost.

  Therefore, a heat storage tank serving as a heat source is provided in the compressor provided in the outdoor unit, and defrosting is performed using the waste heat of the compressor stored in the heat storage tank serving as an auxiliary heat exchanger during heating operation. The thing is proposed (for example, refer patent document 2).

Japanese Patent Laid-Open No. 2001-174101 Japanese Patent No. 4666111

  In the refrigerant flow path shown in FIG. 11, the air conditioner that switches the four-way valve and performs the defrosting operation in the cooling cycle has a problem because the temperature of the refrigerant circulating in the outdoor heat exchanger during the defrosting operation is also high. Without defrosting. However, regarding the air conditioner that performs the defrosting operation while performing the heating operation without switching the four-way valve during the heating operation, the amount of heat to the indoor side is also required. For this reason, the temperature of the refrigerant circulating in the outdoor heat exchanger during the defrosting operation is unlikely to rise, and in particular, the problem that the attached frost tends to remain undissolved between the lower part of the outdoor heat exchanger and the base of the outdoor unit. Had.

  Further, in the refrigerant flow path shown in FIG. 12, by applying the first half of the refrigerant flow path to places where frost is likely to remain undissolved (both ends in the longitudinal direction of the outdoor heat exchanger), relatively high temperature refrigerant can be obtained. Since it can be made to distribute | circulate to this location, the subject of the said frost remaining unmelted can be reduced. However, frost is likely to form on the outdoor heat exchanger as in cold regions, and unmelted frost may be generated in regions where the outdoor air temperature is low. Furthermore, the routing of the refrigerant flow pipe connecting the heat transfer pipes becomes complicated, resulting in an increase in cost, and heating performance deteriorates due to an increase in pressure loss due to the extension of the refrigerant flow path.

  Furthermore, the conventional configuration is a high-cost configuration by adding many parts such as a heat storage tank, a heat storage heat exchanger, a heat storage material, a first electromagnetic valve, and a second electromagnetic valve to an air conditioner that performs air conditioning. In spite of this, there was a problem that there was no opportunity to utilize the heat accumulated in the heat storage tank during the cooling operation.

  An object of the present invention is to solve the above-described conventional problems, and to provide an air conditioner that eliminates unmelted frost and realizes a high-performance and highly efficient heating operation. In addition, the refrigerant circuit that makes up the high-cost heat storage system that could only be used during defrosting during heating operation can be used during cooling operation, and refrigeration that improves both cooling and heating comfort throughout the year. A cycle device is provided.

In order to achieve the above object, an air conditioner according to an aspect of the present invention includes:
A compressor,
An indoor heat exchanger connected to the compressor;
An expansion valve connected to the indoor heat exchanger;
An outdoor heat exchanger connected to the expansion valve;
A four-way valve for switching the connection between the indoor heat exchanger or the outdoor heat exchanger and the compressor,
The refrigerant flow during the defrosting operation of the outdoor heat exchanger is configured in the same direction as the refrigerant flow during the heating operation,
The outdoor heat exchanger comprises a plurality of rows of heat exchangers having a plurality of refrigerant flow paths,
The plurality of rows of heat exchangers are provided with an inlet of a refrigerant channel in a region on the windward side with respect to the air flow and an outlet of the refrigerant channel in another region during heating operation,
The plurality of refrigerant channels are connected so that the number of refrigerant channels increases from the inlet of the refrigerant channel toward the outlet of the refrigerant channel, and the number of refrigerant channels in the region of the inlet of the refrigerant channel is determined. The number of refrigerant channels in the other area is smaller than that.

Moreover, the refrigeration cycle apparatus which is one embodiment of the present invention includes:
A compressor,
An indoor heat exchanger connected to the compressor;
An expansion valve connected to the indoor heat exchanger;
An outdoor heat exchanger connected to the expansion valve;
A four-way valve for switching the connection between the indoor heat exchanger or the outdoor heat exchanger and the compressor;
An auxiliary heat exchanger for heating the refrigerant disposed around the compressor;
An auxiliary heat exchange path for flowing the refrigerant to the suction pipe of the compressor via the auxiliary heat exchanger;
An electromagnetic valve that switches the refrigerant flowing through the pipe between the indoor heat exchanger and the expansion valve to flow to the auxiliary heat exchange path,
A refrigeration cycle apparatus that opens the electromagnetic valve during defrosting to melt and defrost frost adhering to the outdoor heat exchanger,
A solenoid valve control device for performing an operation of opening and closing the solenoid valve;
The electromagnetic valve control device is configured to control the opening / closing operation of the electromagnetic valve when the rotation speed of the compressor reaches a lower limit during cooling operation and the cooling load is lower than the cooling capacity.

  In the air conditioner of the present invention, the air passing through the outdoor heat exchanger and the refrigerant flowing in the heat transfer tube are arranged in counterflow with respect to temperature. Therefore, since heat exchange can be performed efficiently, high efficiency of the heat exchanger can be achieved. In addition, many components such as high-cost heat storage tanks, heat storage heat exchangers, heat storage materials, first solenoid valves, and second solenoid valves that are installed in air conditioners for heating and defrosting operations are used during cooling operations. Since it becomes possible to continue the operation of the compressor using this, it is possible to improve the comfort of both cooling and heating throughout the year.

It is a block diagram of the air conditioner provided with the thermal storage apparatus which concerns on Embodiment 1 of this invention. It is a refrigerant circuit figure at the time of normal heating of the air conditioner of FIG. It is a refrigerant circuit figure at the time of defrosting and heating of the air conditioner of FIG. It is a figure which shows the refrigerant | coolant flow path at the time of the heating operation of the outdoor heat exchanger which concerns on Embodiment 1 of this invention. It is a related figure of the refrigerant | coolant flow pipe number of the outdoor heat exchanger which concerns on Embodiment 1 of this invention, and the refrigerant | coolant flow pipe temperature at the time of normal heating operation. It is a figure which shows the refrigerant | coolant flow path at the time of the air_conditionaing | cooling operation of the outdoor heat exchanger which concerns on Embodiment 1 of this invention. It is a related figure of the refrigerant | coolant flow pipe number of the outdoor heat exchanger which concerns on Embodiment 1 of this invention, and the refrigerant | coolant flow pipe temperature at the time of air_conditionaing | cooling operation. It is a related figure of the refrigerant | coolant distribution pipe number of the outdoor heat exchanger which concerns on Embodiment 1 of this invention, and the refrigerant | coolant distribution pipe temperature at the time of a defrost operation. It is a block diagram of the air conditioner provided with the refrigeration cycle apparatus which concerns on Embodiment 2 of this invention. (A) is a control time chart of the compressor rotation speed of the air conditioner provided with the refrigeration cycle apparatus according to Embodiment 2 of the present invention. (B) is a control time chart of the second solenoid valve. (C) is a time chart of the cooling capacity. It is a refrigerant | coolant flow path figure of the outdoor heat exchanger of the conventional air conditioner. It is a refrigerant | coolant flow path figure of the outdoor heat exchanger of the conventional air conditioner.

The first invention is
A compressor,
An indoor heat exchanger connected to the compressor;
An expansion valve connected to the indoor heat exchanger;
An outdoor heat exchanger connected to the expansion valve;
A four-way valve for switching the connection between the indoor heat exchanger or the outdoor heat exchanger and the compressor,
The refrigerant flow during the defrosting operation of the outdoor heat exchanger is configured in the same direction as the refrigerant flow during the heating operation,
The outdoor heat exchanger comprises a plurality of rows of heat exchangers having a plurality of refrigerant flow paths,
The plurality of rows of heat exchangers are provided with an inlet of a refrigerant channel in a region on the windward side with respect to the air flow and an outlet of the refrigerant channel in another region during heating operation,
The plurality of refrigerant channels are connected so that the number of refrigerant channels increases from the inlet of the refrigerant channel toward the outlet of the refrigerant channel, and the number of refrigerant channels in the region of the inlet of the refrigerant channel is determined. The number of refrigerant channels in the other area is smaller than that.

  With such a configuration, the refrigerant pressure loss is large when the outdoor heat exchanger acts as a condenser or when the outdoor heat exchanger acts as an evaporator and when high heating capacity is required. In this case, the air passing through the outdoor heat exchanger and the refrigerant flowing in the heat transfer tube are arranged in counterflow with respect to temperature. Therefore, since heat can be exchanged efficiently, high capacity and high efficiency of the heat exchanger can be achieved.

In a second aspect of the invention, in particular, in the air conditioner of the first aspect of the invention, the air conditioner further includes a temperature detector that detects the temperature of the outdoor heat exchanger, and the temperature detector is the lowest stage of the plurality of refrigerant flow paths. It arrange | positions in either the piping connected to the exit at the time of the heating operation of this flow path, or the refrigerant | coolant flow path of the lowest stage.
By adopting such a configuration, when the defrosting operation is performed in the same refrigerant flow direction as in the heating operation, the temperature detector is installed in the pipe of the lowermost flow channel where the frost is most likely not melted. Will be placed. For this reason, since the completion of defrosting can be determined at the temperature detected by the temperature detector, the remaining frost can be eliminated. Furthermore, since the preliminary operation time for preventing frost from remaining undissolved can be minimized, the defrosting operation time can be shortened.

In a third aspect of the invention, in particular, in the air conditioner of the first or second aspect of the invention, at least one path among the inlets of the refrigerant channel on the windward side passes through the heat transfer tube at the lowest stage of the outdoor heat exchanger. It is said.
With this configuration, during heating operation and defrosting operation, the refrigerant flowing from the windward side that is relatively hot passes through the lowermost stage of the heat exchanger, and further, the lower part of the outdoor heat exchanger and the base of the outdoor unit It is possible to prevent frost remaining undissolved between the two.

In a fourth aspect of the present invention, in particular, in the air conditioner of any one of the first to third aspects of the present invention, the path serving as the inlet of the windward refrigerant flow path is configured as one path.
With this configuration, when the outdoor heat exchanger is used as a condenser, the heat transfer rate is improved along with the increase in the refrigerant flow rate in the pipe, so that subcooling can be easily taken and the condenser performance can be improved. .

In a fifth aspect of the present invention, in particular, in the air conditioner of any one of the first to fourth aspects, the outdoor heat exchanger is configured by three rows of an upwind row, a central row, and a leeward row, of which at least the center The heat transfer tubes in the row and the lee row are configured to be filled with the increased number of refrigerant channels among the plurality of refrigerant channels.
With this configuration, when the outdoor heat exchanger acts as a condenser, or when the outdoor heat exchanger acts as an evaporator and a high heating capacity is required, the refrigerant pressure loss is large. The air passing through the heat exchanger and the refrigerant flowing in the heat transfer tube are arranged in counterflow with respect to temperature. Therefore, since heat can be exchanged efficiently, the heat exchanger can be greatly increased in capacity and efficiency.

The sixth invention, in particular, in the air conditioner according to any one of the first to fifth inventions, further includes a heat storage device arranged to surround the compressor, and the heat storage device is generated by the compressor. Piping for storing heat, piping so that refrigerant flows from the piping between the indoor heat exchanger and the expansion valve to the heat storage device, and piping so that the refrigerant absorbed by the heat storage device flows to the outdoor heat exchanger Thus, the defrosting operation and the heating operation of the outdoor heat exchanger can be performed simultaneously.
With this configuration, it is possible to supply heat to the room even during the defrosting operation. In addition, the defrosting completion time is determined by a pipe connected to the outlet during heating operation of the lowermost flow path among the plurality of refrigerant flow paths, or by a temperature detector disposed at any position of the lowermost refrigerant flow path. Can be accurately grasped. Therefore, defrosting with a minimum operation time is possible, and indoor comfort can be maintained. For example, it is useful when the temperature of the refrigerant circulating in the outdoor heat exchanger during the defrosting operation does not rise easily, and particularly when frost adhering between the lower part of the outdoor heat exchanger and the base of the outdoor unit tends to remain unmelted.

In a seventh aspect of the present invention, in particular, in the air conditioner according to any one of the first to sixth aspects, the heat storage device stores a heat storage material that stores heat generated by the compressor, and heat stored by the heat storage material. It is set as the structure which consists of the thermal storage heat exchanger for acquiring, and the thermal storage tank which has the said thermal storage material and the said thermal storage heat exchanger inside.
By setting it as this structure, it becomes possible to perform heating operation and defrost operation simultaneously, without using heat sources other than compressors, such as a heater. Further, defrosting is completed by a pipe connected to an outlet at the time of heating operation of the lowermost flow path among the plurality of refrigerant flow paths, or a temperature detector disposed at any position of the lowermost refrigerant flow path Accurately grasp time. Therefore, since the defrosting can be performed with the minimum operation time, an efficient defrosting operation can be performed without wastefully using the finite amount of heat stored in the heat storage material.

The eighth invention
A compressor,
An indoor heat exchanger connected to the compressor;
An expansion valve connected to the indoor heat exchanger;
An outdoor heat exchanger connected to the expansion valve;
A four-way valve for switching the connection between the indoor heat exchanger or the outdoor heat exchanger and the compressor;
A heat storage device for heating the refrigerant disposed around the compressor;
An auxiliary heat exchange path for flowing the refrigerant to the suction pipe of the compressor via the heat storage device;
An electromagnetic valve that switches the refrigerant flowing through the pipe between the indoor heat exchanger and the expansion valve to flow to the auxiliary heat exchange path,
A refrigeration cycle apparatus that opens the electromagnetic valve during defrosting to melt and defrost frost adhering to the outdoor heat exchanger,
A solenoid valve control device for performing an operation of opening and closing the solenoid valve;
The electromagnetic valve control device is configured to control the opening / closing operation of the electromagnetic valve when the rotation speed of the compressor reaches a lower limit during cooling operation and the cooling load is lower than the cooling capacity.

  With this configuration, when the cooling load is reduced, the rotation speed of the compressor reaches the lower limit, and the cooling load falls below the cooling capacity, the solenoid valve control device controls the opening and closing of the solenoid valve. it can. By the opening / closing control of the solenoid valve, a refrigerant flow is generated that flows the refrigerant to the suction pipe of the compressor via the auxiliary heat exchanger in the auxiliary heat exchange path, and the cooling operation is continued while the compressor is continuously operated. be able to. That is, many components such as high-cost heat storage tank, heat storage heat exchanger, heat storage material, first solenoid valve, and second solenoid valve mounted on the air conditioner for heating / defrosting operation are used during cooling operation. Can also be used to continue the operation of the compressor. As a result, it is possible to improve comfort during cooling and heating throughout the year.

In a ninth aspect of the invention, in particular, in the refrigeration cycle apparatus of the eighth aspect of the invention, the electromagnetic valve is operated by a combination of a predetermined opening time and closing time by the electromagnetic valve control device.
With this configuration, the cooling capacity can be controlled with a simple configuration.

According to a tenth aspect of the invention, in particular, in the refrigeration cycle apparatus of the eighth or ninth aspect of the invention, the electromagnetic valve control device controls the opening and closing of the electromagnetic valve based on the detected temperature of the indoor heat exchanger temperature sensor provided in the indoor heat exchanger. It is configured to do.
With this configuration, it is possible to perform a cooling operation while keeping the temperature of the indoor heat exchanger appropriate.

  DESCRIPTION OF EMBODIMENTS Hereinafter, embodiments of an air conditioner and a refrigeration cycle apparatus according to the present invention will be described with reference to the drawings. Note that the present invention is not limited to the embodiments.

(Embodiment 1)
1 is a configuration diagram of an air conditioner including a heat storage device according to Embodiment 1 of the present invention. The air conditioner according to Embodiment 1 of the present invention includes an outdoor unit 2 and an indoor unit 4 that are connected to each other through a refrigerant pipe.

  As shown in FIG. 1, a compressor 6, a four-way valve 8, a strainer 10, an expansion valve 12, and an outdoor heat exchanger 14 are provided inside the outdoor unit 2. An indoor heat exchanger 16 is provided inside the indoor unit 4. These constitute a refrigeration cycle by being connected to each other via a refrigerant pipe.

  More specifically, the compressor 6 and the indoor heat exchanger 16 are connected via a first pipe 18 provided with a four-way valve 8. The indoor heat exchanger 16 and the expansion valve 12 are connected via a second pipe 20 provided with a strainer 10. The expansion valve 12 and the outdoor heat exchanger 14 are connected via a third pipe 22. The outdoor heat exchanger 14 and the compressor 6 are connected via a fourth pipe 24.

  A four-way valve 8 is disposed in the middle portion of the fourth pipe 24. The fourth pipe 24 on the refrigerant suction side of the compressor 6 is provided with an accumulator 26 for separating the liquid phase refrigerant and the gas phase refrigerant. The compressor 6 and the third pipe 22 are connected via a fifth pipe 28, and the first solenoid valve 30 is provided in the fifth pipe 28.

  Further, a heat storage tank 32 is provided around the compressor 6. A heat storage heat exchanger 34 is provided inside the heat storage tank 32, and a heat storage material (for example, ethylene glycol aqueous solution) 36 for exchanging heat with the heat storage heat exchanger 34 is filled therein. In the air conditioner according to Embodiment 1 of the present invention, the heat storage device includes any one of the heat storage tank 32, the heat storage heat exchanger 34, and the heat storage material 36.

  The second pipe 20 and the heat storage heat exchanger 34 are connected via a sixth pipe 38. The heat storage heat exchanger 34 and the fourth pipe 24 are connected via a seventh pipe 40, and a second electromagnetic valve 42 is provided in the sixth pipe 38.

  In the interior of the indoor unit 4, in addition to the indoor heat exchanger 16, a blower fan (not shown), upper and lower blades (not shown), and left and right blades (not shown) are provided. The indoor heat exchanger 16 performs heat exchange between the indoor air sucked into the indoor unit 4 by the blower fan and the refrigerant flowing inside the indoor heat exchanger 16. The indoor heat exchanger 16 blows out air heated by heat exchange into the room during heating operation, and blows out air cooled by heat exchange into the room during cooling operation. The upper and lower blades change the direction of air blown from the indoor unit 4 up and down as necessary, and the left and right blades change the direction of air blown from the indoor unit 4 to right and left as needed.

  The compressor 6, the blower fan, the upper and lower blades, the left and right blades, the four-way valve 8, the expansion valve 12, the electromagnetic valves 30 and 42, etc. are electrically connected to a control device (not shown, for example, a microcomputer). Controlled by

  In the refrigeration cycle apparatus according to Embodiment 1 of the present invention having the above-described configuration, the mutual connection relationship and function of each component will be described together with the flow of refrigerant, taking the heating operation as an example.

  The refrigerant discharged from the discharge port of the compressor 6 reaches the indoor heat exchanger 16 from the four-way valve 8 through the first pipe 18. The refrigerant condensed by exchanging heat with the indoor air in the indoor heat exchanger 16 passes through the second pipe 20 through the indoor heat exchanger 16, expands through the strainer 10 that prevents foreign matter from entering the expansion valve 12. To valve 12. The refrigerant decompressed by the expansion valve 12 reaches the outdoor heat exchanger 14 through the third pipe 22. The refrigerant evaporated by exchanging heat with outdoor air in the outdoor heat exchanger 14 returns to the suction port of the compressor 6 through the fourth pipe 24, the four-way valve 8, and the accumulator 26.

  The fifth pipe 28 branched from the discharge port of the compressor 6 of the first pipe 18 and the four-way valve 8 is connected to the expansion valve 12 of the third pipe 22 and the outdoor heat exchanger 14 via the first electromagnetic valve 30. Have joined together.

  Furthermore, the heat storage tank 32 in which the heat storage material 36 and the heat storage heat exchanger 34 are housed is disposed so as to be in contact with and surround the compressor 6, and heat generated by the compressor 6 is accumulated in the heat storage material 36. The sixth pipe 38 branched between the indoor heat exchanger 16 and the strainer 10 from the second pipe 20 reaches the inlet of the heat storage heat exchanger 34 via the second electromagnetic valve 42. Then, the seventh pipe 40 that has come out from the outlet of the heat storage heat exchanger 34 joins between the four-way valve 8 and the accumulator 26 in the fourth pipe 24.

  FIG. 2 is a refrigerant circuit diagram during normal heating of the air conditioner of FIG. The operation during normal heating operation will be described with reference to FIG.

  During the normal heating operation, the first solenoid valve 30 and the second solenoid valve 42 are closed. For this reason, the refrigerant does not flow in the refrigerant circuit of the portion constituted by the fifth pipe 28, the sixth pipe 38 and the seventh pipe 40.

  As described above, the refrigerant discharged from the discharge port of the compressor 6 passes through the first pipe 18 and reaches the indoor heat exchanger 16 from the four-way valve 8. The refrigerant condensed by exchanging heat with the indoor air in the indoor heat exchanger 16 exits the indoor heat exchanger 16 and reaches the expansion valve 12 through the second pipe 20. The refrigerant decompressed by the expansion valve 12 reaches the outdoor heat exchanger 14 through the third pipe 22. The refrigerant evaporated by exchanging heat with outdoor air in the outdoor heat exchanger 14 returns from the four-way valve 8 to the suction port of the compressor 6 through the fourth pipe 24.

  The heat generated in the compressor 6 is stored in the heat storage material 36 housed in the heat storage tank 32 from the outer wall of the compressor 6 through the outer wall of the heat storage tank 32.

  FIG. 3 is a refrigerant circuit diagram during defrosting / heating of the air conditioner of FIG. 1. The operation during defrosting / heating will be described with reference to FIG. In the figure, solid line arrows indicate the flow of the refrigerant during heating, and broken line arrows indicate the flow of the refrigerant during defrosting.

  When the outdoor heat exchanger 14 is frosted during the above-described normal heating operation and the frosted frost grows, the ventilation resistance of the outdoor heat exchanger 14 increases and the air flow decreases, and the evaporation in the outdoor heat exchanger 14 increases. The temperature drops. As shown in FIG. 3, the air conditioner according to Embodiment 1 of the present invention is provided with a first temperature sensor 44 that detects the piping temperature of the outdoor heat exchanger 14. When the first temperature sensor 44 detects that the evaporating temperature is lower than that during non-frosting, an instruction from the normal heating operation to the defrosting / heating operation is output by the control device.

  When the normal heating operation is shifted to the defrosting / heating operation, the first electromagnetic valve 30 and the second electromagnetic valve 42 are controlled to be opened. In addition to the refrigerant flow during the normal heating operation described above, a part of the gas-phase refrigerant exiting from the discharge port of the compressor 6 passes through the fifth pipe 28 and the first electromagnetic valve 30 and passes through the third pipe 22. To join. Then, the outdoor heat exchanger 14 is heated and condensed to form a liquid phase, and then returns to the suction port of the compressor 6 through the fourth pipe 24 and the four-way valve 8 and the accumulator 26.

  Further, a part of the liquid-phase refrigerant that is divided between the indoor heat exchanger 16 and the strainer 10 in the second pipe 20 passes through the sixth pipe 38 and the second electromagnetic valve 42, and then is stored in the heat storage material 36 in the heat storage heat exchanger 34. Evaporates and vaporizes. Then, the refrigerant passes through the seventh pipe 40 and merges with the refrigerant passing through the fourth pipe 24, and returns from the accumulator 26 to the suction port of the compressor 6.

  The refrigerant returning to the accumulator 26 includes the liquid phase refrigerant returning from the outdoor heat exchanger 14. By mixing this with the high-temperature gas phase refrigerant returning from the heat storage heat exchanger 34, The evaporation of the phase refrigerant is promoted. As a result, the liquid refrigerant does not return to the compressor 6 through the accumulator 26, and the reliability of the compressor 6 can be improved.

  The temperature of the outdoor heat exchanger 14 that has become below freezing due to frost adhesion at the start of the defrosting / heating operation is heated by the gas-phase refrigerant discharged from the discharge port of the compressor 6, and the frost is melted at around zero degrees. When the melting of the outdoor heat exchanger 14 ends, the temperature of the outdoor heat exchanger 14 begins to rise again. As shown in FIG. 3, the air conditioner according to Embodiment 1 of the present invention is provided with a second temperature sensor 45 that detects the piping temperature of the outdoor heat exchanger 14. When the temperature rise of the outdoor heat exchanger 14 is detected by the second temperature sensor 45, it is determined that the defrosting is completed, and an instruction from the defrosting / heating operation to the normal heating operation is output by the control device.

The outdoor heat exchanger 14 of the air conditioner configured as described above will be described in detail.
FIG. 4 is a diagram illustrating the refrigerant flow path during the heating operation of the outdoor heat exchanger according to Embodiment 1 of the present invention. FIG. 5 is a graph showing the relationship between the refrigerant flow tube number of the outdoor heat exchanger and the refrigerant flow tube temperature during normal heating operation. The refrigerant circulation pipe means a heat transfer pipe.

  As shown in FIG. 4, the outdoor heat exchanger 14 includes a plurality of heat exchangers in three rows, that is, a windward row, a central row, and a leeward row, and has a plurality of refrigerant flow paths. In addition, it defines as an upwind row | line | column, a center row | line | column, and a leeward row | line | column in order from the one near the air flow 55 at the time of heating operation. The plurality of rows of heat exchangers are provided with an inlet of the refrigerant flow path in the windward row and an outlet of the refrigerant flow passage in the leeward row. The plurality of refrigerant channels are connected so that the number of refrigerant channels increases from the inlet of the refrigerant channel in the windward row toward the outlet of the refrigerant channel in the leeward row. In particular, at the time of heating operation used as an evaporator, the inlet of the refrigerant flow path is arranged in the lowermost refrigerant circulation pipe 51 in the windward row. Further, the outlets of the refrigerant flow paths are arranged in the refrigerant flow pipes 54a to 54f in the leeward row. For this reason, the refrigerant that has flowed in from the refrigerant flow pipe 51 is divided into two refrigerant flow paths of the wind-flow line refrigerant flow pipes 52a and 52b. Then, the refrigerant is divided into six refrigerant flow paths of the refrigerant flow pipes 53a to 53f and flows out from the refrigerant flow pipes 54a to 54f in the leeward row.

  As shown in FIG. 5, during the heating operation, the refrigerant flow pipe 51 serving as the inlet of the refrigerant flow path is at a higher temperature than the other flow pipes. For this reason, when the refrigerant | coolant circulation pipe | tube 51 which becomes high temperature is arrange | positioned in the lowest stage of the upwind row | line | column of the outdoor heat exchanger 14 as mentioned above, especially the heat exchange of the upwind row | line | column which is easy to generate | occur | produce the frost melt | dissolution residue. The high-temperature refrigerant circulation pipe 51 is disposed near the vessel and the base. As a result, in the air conditioner according to Embodiment 1 of the present invention, during the heating operation, the heat of the refrigerant flow pipe 51 can be used to reduce unmelted frost attached to the outdoor heat exchanger 14. it can.

  Further, in the air conditioner according to Embodiment 1, the pressure loss is reduced by reducing the refrigerant flow rate after 53, that is, the refrigerant flow pipes 53 and later, in which the central row and the leeward row of the outdoor heat exchanger 14 are divided into six flow paths. The refrigerant flow path can be filled. As a result, the air passing through the outdoor heat exchanger 14 and the refrigerant flowing in the heat transfer tubes are arranged in counterflow as the temperature, and as shown in FIG. It can be. Therefore, the efficiency of the heat exchanger can be further increased, and the heating capacity can be improved.

Next, the cooling operation will be described.
FIG. 6 is a diagram showing the refrigerant flow path during the cooling operation of the outdoor heat exchanger according to Embodiment 1 of the present invention. FIG. 7 is a diagram showing the relationship between the refrigerant flow tube number of the outdoor heat exchanger and the refrigerant flow tube temperature during the cooling operation.

  As shown in FIG. 6, during the cooling operation in which the outdoor heat exchanger 14 acts as a condenser, the refrigerant flow is opposite to that during the heating operation. In other words, during the cooling operation, the inlet of the refrigerant flow path becomes the refrigerant flow pipes 54a to 54f, and the outlet of the refrigerant flow path becomes the refrigerant flow pipe 51. Therefore, during the cooling operation, the refrigerant that has flowed in from the leeward row refrigerant circulation pipes 54a to 54f passes through the six refrigerant flow paths of the refrigerant circulation pipes 53a to 53f. Then, the refrigerant flows in the two refrigerant flow paths of the refrigerant flow pipes 52 a and 52 b in the windward row and flows out from the refrigerant flow pipe 51.

  As shown in FIG. 7, during the cooling operation, the refrigerant flow pipes 54 in the leeward row are hot, contrary to the heating operation. In Embodiment 1 of the present invention, the relatively high-temperature refrigerant flow pipes 54 are arranged in the leeward row, and the relatively low-temperature refrigerant flow pipes 51 and 52 are arranged in the windward row. Therefore, the air passing through the outdoor heat exchanger 14 and the refrigerant flowing in the heat transfer tube are arranged in counterflow with respect to temperature. Therefore, since heat can be exchanged efficiently, the efficiency of the heat exchanger can be increased and the cooling capacity can be improved.

  Furthermore, by using the refrigerant outlet when the outdoor heat exchanger 14 acts as a condenser as one path and arranging the refrigerant outlet in the windward row, the heat transfer rate improvement and refrigerant temperature associated with the improvement of the refrigerant flow velocity in the pipe The air temperature difference can be maximized. Thereby, it becomes easy to take a subcool and the cooling capacity can be further improved.

Next, the defrosting / heating operation will be described.
FIG. 8 is a graph showing the relationship between the refrigerant flow tube number of the outdoor heat exchanger and the refrigerant flow tube temperature during the defrosting operation.

  During the defrosting / heating operation, the refrigerant flow is the same as in the normal heating operation shown in FIG. The refrigerant flowing in from the refrigerant circulation pipe 51 is divided into two refrigerant flow paths of the up-stream refrigerant circulation pipes 52a and 52b. Thereafter, the refrigerant is divided into six refrigerant flow paths of the refrigerant flow pipes 53a to 53f and flows out from the refrigerant flow pipes 54a to 54f. At this time, as shown in FIG. 8, the refrigerant flow pipe 51 having the highest temperature is disposed near the wind-side heat exchanger and the base where the frost is not easily melted. Furthermore, the remaining frost can be reduced.

  Further, as shown in FIG. 4, in the first embodiment of the present invention, the second temperature sensor 45 may be arranged in the lowermost refrigerant circulation pipe 54f among the refrigerant circulation pipe outlets divided into six paths. . It can be used as a defrosting completion signal that the temperature detected by the second temperature sensor 45 has reached a predetermined temperature. As a result, even when the outdoor heat exchanger 14 has a three-row configuration for high performance, the melting of frost adhering between the lower part of the heat exchanger in the central row and the leeward row and the base of the outdoor unit 2 is melted. The rest can be surely prevented.

  In Embodiment 1 of the present invention, a heat storage device may be used. When the heat storage device is used, the amount of heat can be supplied into the room even during defrosting, and the defrosting operation and the heating operation can be performed simultaneously. Further, as described above, the defrosting completion time can be accurately grasped by the first temperature sensor 44 or the second temperature sensor 45. With this configuration, even when the temperature of the refrigerant flowing through the outdoor heat exchanger 14 is unlikely to rise, extra frost is prevented from remaining between the lower portion of the outdoor heat exchanger 14 and the base of the outdoor unit 2. There is no need to lengthen the heating / defrosting operation time. In addition, it is possible to minimize the heating / defrosting operation time in which the heating capacity is generally lower than that of the normal heating operation. Therefore, indoor comfort can be maintained as compared with an air conditioner that switches the four-way valve 8 and performs the defrosting operation in the cooling cycle.

  Further, when the heat generated in the compressor 6 is stored in the heat storage material 36 constituting the heat storage device as in the first embodiment, and the stored heat is used during heating / defrosting operation, the heat storage material 36 that can be used. The amount of stored heat is constant regardless of the defrosting time. For this reason, it is necessary to finish a defrost operation in a short time, and the usefulness of this system increases further.

  In Embodiment 1 of this invention shown in FIG. 4, the temperature detector 45 which detects completion | finish of defrost is arrange | positioned in the refrigerant | coolant distribution pipe 54f of the lowest stage among the refrigerant | coolant distribution pipe outlets divided into 6 paths. This temperature detector 45 may additionally arrange a temperature detector in the uppermost refrigerant flow tube 54a among the refrigerant flow tube outlets divided into six paths. In this case, it is possible to prevent frost from remaining undissolved even when frost remains undissolved between the upper part of the outdoor heat exchanger 14 and the top plate of the outdoor unit 2. Furthermore, defrosting can be performed with a minimum operation time, and indoor comfort can be maintained.

(Embodiment 2)
A refrigeration cycle apparatus according to Embodiment 2 of the present invention will be described with reference to the drawings, taking as an example a case where it is mounted on an air conditioner. The present invention is not limited to the second embodiment.

  FIG. 9 shows a configuration of an air conditioner including the refrigeration cycle apparatus according to Embodiment 2 of the present invention. The same components as those in the first embodiment are denoted by the same reference numerals, and detailed description thereof is omitted. Further, as described in the configuration of the first embodiment, the branch from the discharge port of the compressor 6 of the first pipe 18 and the four-way valve 8, and the expansion valve 12 of the third pipe 22 via the first electromagnetic valve 30 The fifth pipe 28 that merges between the outdoor heat exchangers 14 is not shown for simplicity in the second embodiment of the present invention.

  In FIG. 9, the air conditioner according to the second embodiment is provided with an electromagnetic valve control device 60 in addition to the configuration of the first embodiment. The electromagnetic valve control device 60 is electrically connected to the indoor heat exchanger temperature sensor 61, and when the rotational speed of the compressor 6 reaches the lower limit, the electromagnetic valve control device 60 is connected to the sixth pipe 38 based on the temperature of the indoor heat exchanger 14. The opening and closing of the provided second electromagnetic valve 42 is driven and controlled.

  Since the operation | movement at the time of heating operation is the same as that of the air conditioner which concerns on Embodiment 1 shown in FIG. 2, description is abbreviate | omitted.

  Next, the operation during the cooling operation will be described. During the cooling operation, the refrigerant discharged from the discharge port of the compressor 6 reaches the outdoor heat exchanger 14 from the four-way valve 8. The refrigerant condensed by exchanging heat with outdoor air in the outdoor heat exchanger 14 exits the outdoor heat exchanger 14 and reaches the expansion valve 12 through the pipe 22. The refrigerant decompressed by the expansion valve 12 reaches the indoor heat exchanger 16 through the pipe 20 via the strainer 10. Refrigerant evaporated by exchanging heat with indoor air in the indoor heat exchanger 16 returns to the suction port of the compressor 6 through the pipe 18, the four-way valve 8, the fourth pipe 24 and the accumulator 26.

  The sixth pipe 38 branched from the second pipe 20 and joining the fourth pipe 24 via the second solenoid valve 42, the auxiliary heat exchanger, and the seventh pipe 40 serves as an auxiliary heat exchange path. During the cooling operation, the second electromagnetic valve 42 is normally controlled to be closed, and the refrigerant does not flow through the auxiliary heat exchange path. In the second embodiment, the auxiliary heat exchanger will be described as a heat storage heat exchanger 34.

  Here, when the cooling load in the indoor unit 4 is small, the air conditioner performs control so as to reduce the number of rotations of the compressor 6 and to suppress the cooling capacity. However, when the rotational speed of the compressor 6 reaches the lower limit, the cooling capacity cannot be suppressed below that, and the cooling load is lower than the cooling capacity, that is, the room temperature value is lower than the set temperature, and the compressor is eventually reached. 6 must be stopped. Then, when the compressor 6 stops, the cooling capacity becomes zero and the compressor 6 is restarted, and the compressor start / stop operation is repeated. This compressor start / stop operation is less efficient than the state in which the compressor 6 is continuously operated due to a loss or the like when the compressor 6 is restarted.

  Therefore, in the air conditioner according to Embodiment 2 of the present invention, when the cooling load in the indoor unit 4 described above is small, the rotation speed of the compressor 6 reaches the lower limit, and the cooling load falls below the cooling capacity, The electromagnetic valve control device 60 controls the opening and closing of the second electromagnetic valve 42. By opening / closing control of the second electromagnetic valve 42, the second pipe 20 branches to the sixth pipe 38 that merges with the fourth pipe 24 via the second electromagnetic valve 42, the heat storage heat exchanger 34, and the seventh pipe 40. The refrigerant flows through the auxiliary heat exchange path. For this reason, the cooling operation can be continued while the compressor 6 is continuously operated. At that time, the electromagnetic valve control device 60 controls the opening amount of the second electromagnetic valve 42, that is, the amount of refrigerant flowing to the indoor heat exchanger 16 through the pipe 20 based on the output from the indoor heat exchanger temperature sensor 61. And control the cooling capacity.

  FIG. 10 is a control time chart according to the second embodiment of the present invention. (A) is a control time chart of the compressor rotation speed of the air conditioner provided with the refrigeration cycle apparatus according to Embodiment 2 of the present invention. (B) is a control time chart of the second solenoid valve. (C) is a time chart of the cooling capacity.

  As described above, when the cooling load is small in the indoor unit 4, as shown in FIGS. 10A and 10C, the air conditioner is controlled so as to reduce the rotation speed of the compressor 6 and suppress the cooling capacity to a small value. To do. When the rotational speed of the compressor 6 reaches the lower limit Fmin at time T1, the cooling capacity cannot be made smaller than Qmin after time T1.

  The air conditioner according to Embodiment 2 of the present invention is configured to turn on / off the second electromagnetic valve 42, for example, by a combination of a predetermined opening time and closing time after the time T2. With this configuration, the solenoid valve 42 can be opened and closed (ON / OFF), and the refrigerant can freely flow through the auxiliary heat exchange path. That is, as shown in FIGS. 10B and 10C, after time T2, the cooling capacity can be lowered when the electromagnetic valve 42 is ON, and the cooling capacity can be increased when the electromagnetic valve 42 is OFF. Therefore, if the cooling capacity after the time T2 is averaged, it is possible to perform an operation that is suppressed to be lower than the cooling capacity Qmin, so that the above-described compressor start / stop operation is not performed, and a decrease in efficiency can be prevented. The reason for opening / closing (ON / OFF) the electromagnetic valve 42 is, for example, that the cooling capacity is too low when the electromagnetic valve 42 is in the opening operation (ON). Therefore, in the air conditioner according to Embodiment 2 of the present invention, the electromagnetic valve 42 is operated to open and close (ON / OFF), and an average cooling capacity is obtained.

  Further, based on the temperature of the indoor heat exchanger 16 detected by the indoor heat exchanger temperature sensor 61 shown in FIG. 9, the ON / OFF time of the second electromagnetic valve 42 is adjusted so as to keep this temperature at a predetermined temperature. May be. Thereby, the cooling capacity control below the cooling capacity Qmin in the compressor rotation speed lower limit state can be more effectively performed.

  In the second embodiment, the heat exchanger 34 provided so as to surround the compressor 6 is described as an example of the auxiliary heat exchanger. However, the heat exchanger 34 is not limited to this and may be of other configurations. Good.

  As described above, in the refrigeration cycle apparatus according to Embodiment 2 of the present invention, the refrigerant circuit constituting the high-cost heat storage system that can only be used during the defrosting of the heating operation can be utilized also during the cooling operation. . As a result, it is possible to improve comfort during cooling and heating throughout the year.

  The present invention uses a high-cost component such as a heat storage tank, a heat storage heat exchanger, a heat storage material, a first electromagnetic valve, and a second electromagnetic valve used for defrosting during heating at the time of low load during cooling. Loss due to starting and stopping can be reduced, and comfort during both cooling and heating can be improved throughout the year. Therefore, it is useful not only for small air conditioners but also for medium-sized and large air conditioners such as packaged air conditioners. Moreover, since this invention improves the efficiency of a heat exchanger and enables completion of a defrosting operation in a short time, it is useful also for a refrigerator, a heat pump type water heater, etc.

DESCRIPTION OF SYMBOLS 2 Outdoor unit 4 Indoor unit 6 Compressor 8 Four-way valve 10 Strainer 12 Expansion valve 14 Outdoor heat exchanger 16 Indoor heat exchanger 18, 20, 22, 24, 25 Piping 26 Accumulator 28 Piping 30 Electromagnetic valve 32 Thermal storage tank 34 Thermal storage heat Exchanger 36 Heat storage material 38, 40 Piping 42 Solenoid valve 43 Capillary tube 44 First temperature sensor 45 Second temperature sensor 51 Refrigerant flow pipe 52a, 52b Refrigerant flow pipe 53a, 53b, 53c, 53d, 53e, 53f Refrigerant flow pipe 54a 54b, 54c, 54d, 54e, 54f Refrigerant flow pipe 55 Air flow 60 Solenoid valve control device 61 Indoor heat exchanger temperature sensor

Claims (10)

A compressor,
An indoor heat exchanger connected to the compressor;
An expansion valve connected to the indoor heat exchanger;
An outdoor heat exchanger connected to the expansion valve;
A four-way valve for switching the connection between the indoor heat exchanger or the outdoor heat exchanger and the compressor,
The refrigerant flow during the defrosting operation of the outdoor heat exchanger is configured in the same direction as the refrigerant flow during the heating operation,
The outdoor heat exchanger comprises a plurality of rows of heat exchangers having a plurality of refrigerant flow paths,
The plurality of rows of heat exchangers are provided with an inlet of a refrigerant channel in a region on the windward side with respect to the air flow and an outlet of the refrigerant channel in another region during heating operation,
The plurality of refrigerant channels are connected so that the number of refrigerant channels increases from the inlet of the refrigerant channel toward the outlet of the refrigerant channel, and the number of refrigerant channels in the region of the inlet of the refrigerant channel is determined. The air conditioner is configured to have a smaller number of refrigerant channels in the other area. A temperature detector for detecting the temperature of the outdoor heat exchanger;
The temperature detector is arranged at any one of a pipe connected to an outlet during heating operation of a lowermost flow path among the plurality of refrigerant flow paths or a lowermost refrigerant flow path. Item 2. An air conditioner according to Item 1.   3. The air conditioner according to claim 1, wherein at least one path among the inlets of the refrigerant flow path passes through a heat transfer tube at a lowermost stage of the outdoor heat exchanger.   The air conditioner according to any one of claims 1 to 3, wherein a path serving as an inlet of the refrigerant flow path is a single path.   The outdoor heat exchanger is composed of three rows, an upwind row, a central row, and a downwind row, and at least the heat transfer tubes in the central row and the leeward row are refrigerants after increasing among the plurality of refrigerant channels. The air conditioner according to any one of claims 1 to 4, wherein the air conditioner is filled with a flow path. A heat storage device arranged to surround the compressor;
The heat storage device stores heat generated by the compressor,
Piping so that the refrigerant flows from the piping between the indoor heat exchanger and the expansion valve to the heat storage device,
The refrigerant that has absorbed heat by the heat storage device is piped so as to flow into the suction pipe of the compressor, whereby the defrosting operation and the heating operation of the outdoor heat exchanger can be performed simultaneously. The air conditioner as described in any one of Claims 1 thru | or 5.   The heat storage device includes a heat storage material for storing heat generated by the compressor, and a heat storage heat exchanger for acquiring heat stored by the heat storage material. The air conditioner as described in any one of. A compressor,
An indoor heat exchanger connected to the compressor;
An expansion valve connected to the indoor heat exchanger;
An outdoor heat exchanger connected to the expansion valve;
A four-way valve for switching the connection between the indoor heat exchanger or the outdoor heat exchanger and the compressor;
An auxiliary heat exchanger for heating the refrigerant disposed around the compressor;
An auxiliary heat exchange path for flowing the refrigerant to the suction pipe of the compressor via the auxiliary heat exchanger;
An electromagnetic valve that switches the refrigerant flowing through the pipe between the indoor heat exchanger and the expansion valve to flow to the auxiliary heat exchange path,
A refrigeration cycle apparatus that opens the electromagnetic valve during defrosting to melt and defrost frost adhering to the outdoor heat exchanger,
A solenoid valve control device for performing an operation of opening and closing the solenoid valve;
The electromagnetic valve control device is a refrigeration cycle device that controls the opening / closing operation of the electromagnetic valve when the rotation speed of the compressor reaches a lower limit during cooling operation and the cooling load is lower than the cooling capacity.   The refrigeration cycle apparatus according to claim 8, wherein the electromagnetic valve control device operates the electromagnetic valve by a combination of a predetermined opening time and closing time. The indoor heat exchanger further includes an indoor heat exchanger temperature sensor,
The refrigeration cycle apparatus according to claim 8 or 9, wherein the electromagnetic valve control device controls opening and closing of the electromagnetic valve according to a temperature detected by the indoor heat exchanger temperature sensor.

Images