Patent Grant
11808496
The present application is based on PCT filing PCT/JP2018/030941, filed Aug. 22, 2018, the entire contents of which are incorporated herein by reference.
The present disclosure relates to a heat exchanger including a distributor to distribute two-phase gas-liquid refrigerant to plural heat transfer tubes, and an air-conditioning apparatus including the heat exchanger.
Air-conditioning apparatuses include, as one component of the refrigeration cycle circuit, a heat exchanger that functions as an evaporator. Two-phase gas-liquid refrigerant, which is a mixture of gas refrigerant and liquid refrigerant, flows into the evaporator. Some related-art heat exchangers that function as evaporators include plural heat transfer tubes. Further, some proposed related-art heat exchangers that function as evaporators and include plural heat transfer tubes include a distributor to distribute two-phase gas-liquid refrigerant to individual heat transfer tubes (see, for example, Patent Literature 1). Such related-art distributor includes a body part, and plural flow-splitting parts. The body part is formed as, for example, a tubular component. The body part includes an inlet for two-phase gas-liquid refrigerant, and a flow passage in which the two-phase gas-liquid refrigerant entering through the inlet flows upward. The flow-splitting parts are formed as, for example, tubular components, and disposed with a predetermined spacing from each other in the up and down direction. Each flow-splitting part provides communication between the passage within the body part, and one of the heat transfer tubes. That is, the flow of two-phase gas-liquid refrigerant entering the passage within the body part splits at the flow-splitting parts into separate streams before entering the individual heat transfer tubes.
Two-phase gas-liquid refrigerant flowing upward in the passage within the body part is discharged sequentially from lower positioned flow-splitting parts. This results in reduced upward momentum of the two-phase gas-liquid refrigerant near higher positioned flow-splitting parts. Consequently, for example, under conditions of low refrigerant circulation rate within the refrigeration cycle circuit such as during low-capacity operation of the air-conditioning apparatus, if the upward momentum of two-phase gas-liquid refrigerant becomes less than or equal to a certain value, gravity hinders the upward flow of liquid refrigerant, which has a greater density than gas refrigerant. Liquid refrigerant is thus unable to reach higher positioned flow-splitting parts. This results in no liquid refrigerant being supplied to some of higher positioned heat transfer tubes, leading to degradation of the heat exchange performance of the evaporator.
One way to avoid the above-mentioned problem is to reduce the effective cross-sectional area of the passage within the body part to increase the upward momentum of the two-phase gas-liquid refrigerant. However, reducing the effective cross-sectional area of the passage within the body part has the following problem. For example, under conditions of high refrigerant circulation rate within the refrigeration cycle circuit such as during high-capacity operation of the air-conditioning apparatus, higher positioned heat transfer tubes receive excessive supply of liquid refrigerant. Another problem with reducing the effective cross-sectional area of the passage within the body part is that under conditions of high refrigerant circulation rate within the refrigeration cycle circuit, the pressure loss within the distributor increases. For this reason, reducing the effective cross-sectional area of the passage within the body part results in degradation of the heat exchange performance of the evaporator under conditions of high refrigerant circulation rate within the refrigeration cycle circuit. Therefore, reducing the effective cross-sectional area of the passage within the body part does not make it possible to maintain the heat exchange performance of the evaporator over wide operating conditions of the air-conditioning apparatus ranging from low-capacity operation to high-capacity operation. This leads to reduced energy-saving performance of the air-conditioning apparatus.
Another conceivable way to address the above problem, that is, degradation of the heat exchange performance of the evaporator under conditions of low refrigerant circulation rate within the refrigeration cycle circuit, is to split the passage within the body part into smaller portions by use of partition walls, as with the distributor disclosed in Patent Literature 1. Use of this approach, however, increases the number of components of the distributor, leading to increased material and machining costs of the distributor. This translates into increased manufacturing cost of the heat exchanger that functions as an evaporator.
The present disclosure has been made to address the above-mentioned problems, and accordingly a first object of the present disclosure is to provide a heat exchanger capable of, when functioning as an evaporator, maintaining its heat exchange performance over wide operating conditions of the air-conditioning apparatus ranging from low-capacity operation to high-capacity operation, and minimizing an increase in manufacturing cost. A second object of the present disclosure is to provide an air-conditioning apparatus including such a heat exchanger.
A heat exchanger according to an embodiment of the present disclosure includes plural heat transfer tubes, and a distributor. The heat transfer tubes are disposed with a predetermined spacing from each other in the up and down direction. The distributor is configured to distribute refrigerant to the heat transfer tubes. The distributor includes a body part, and plural flow-splitting parts. The body part includes a first inlet for refrigerant, and a first passage in which refrigerant entering through the first inlet flows upward. The flow-splitting parts each include a second passage, each flow-splitting part communicating at a second inlet with the first passage and communicating at an outlet with one of the heat transfer tubes. The second inlets of at least two of the flow-splitting parts each communicate with the first passage at a location above the first inlet. Among the heat transfer tubes each communicating with the outlet of the flow-splitting part whose second inlet communicates with the first passage at a location above the first inlet, at least the first one of the heat transfer tubes from the top is defined as a first heat transfer tube. Among the heat transfer tubes each communicating with the outlet of the flow-splitting part whose second inlet communicates with the first passage at a location above the first inlet, the heat transfer tube positioned below the first heat transfer tube is defined as a second heat transfer tube. The flow-splitting part whose outlet communicates with the first heat transfer tube is defined as a first flow-splitting part. The flow-splitting part whose outlet communicates with the second heat transfer tube is defined as a second flow-splitting part. The second inlet of the first flow-splitting part communicates with the first passage at a location below the second inlet of the second flow-splitting part that communicates with the first passage at the highest location.
Further, an air-conditioning apparatus according to an embodiment of the present disclosure includes the heat exchanger according to an embodiment of the present disclosure that functions as an evaporator, and a fan that supplies air to the heat exchanger.
In the heat exchanger according to an embodiment of the present disclosure, the first heat transfer tube, which is a higher positioned heat transfer tube among the heat transfer tubes of the heat exchanger, communicates with the first passage of the body part at a location below a location where one or more second heat transfer tubes positioned below the first heat transfer tube communicate with the first passage. Consequently, when used as an evaporator, the heat exchanger according to an embodiment of the present disclosure makes it possible to prevent the first heat transfer tube, which is a higher positioned heat transfer tube, from receiving no supply of liquid refrigerant during low-capacity operation of the air-conditioning apparatus. Thus, using the heat exchanger according to an embodiment of the present disclosure as an evaporator makes it possible to maintain the heat exchange performance of the evaporator during low-capacity operation of the air-conditioning apparatus. In this regard, the heat exchanger according to an embodiment of the present disclosure makes it possible to maintain the heat exchange performance of the evaporator during low-capacity operation of the air-conditioning apparatus without reducing the effective cross-sectional area of the first passage. This means that using the heat exchanger according to an embodiment of the present disclosure makes it possible to maintain the heat exchange performance of the evaporator also during high-capacity operation of the air-conditioning apparatus. Further, the distributor of the heat exchanger according to an embodiment of the present disclosure allows the number of components to be reduced in comparison to a distributor having within its body a passage that is divided into smaller portions by use of partition walls. As a result, the heat exchanger according to an embodiment of the present disclosure allows for reduced manufacturing cost in comparison to a heat exchanger including a distributor having within its body a passage that is divided into smaller portions by use of partition walls. That is, the heat exchanger according to an embodiment of the present disclosure is capable of, when functioning as an evaporator, maintaining its heat exchange performance over wide operating conditions of the air-conditioning apparatus ranging from low-capacity operation to high-capacity operation, and minimizing an increase in manufacturing cost.
A heat exchanger and an air-conditioning apparatus according to exemplary embodiments of the present disclosure will be described below with reference to the drawings. In the drawings below, features designated by the same reference signs represent the same or corresponding features. The specific arrangements of features described in the following embodiments are illustrative only. The heat exchanger and the air-conditioning apparatus according to the present disclosure are not limited to the specific features described in the following embodiments. Features to be combined with each other may not necessarily be features in the same embodiment but may be features described in different embodiments. In the drawings below, the relative sizes of various components may in some cases differ from those of the actual embodiment of the present disclosure.
An air-conditioning apparatus 1 includes a compressor 4 that compresses refrigerant, an indoor heat exchanger 6 that functions as a condenser, an expansion device 7 that decompresses refrigerant to cause the refrigerant to expand, and the outdoor heat exchanger 8 that functions as an evaporator. The compressor 4, the indoor heat exchanger 6, the expansion device 7, and the outdoor heat exchanger 8 are sequentially connected by refrigerant pipes to form a refrigeration cycle circuit. In Embodiment 1, the indoor heat exchanger 6 also includes a four-way valve 5, which is used to switch the passages of refrigerant discharged from the compressor 4 to thereby make the indoor heat exchanger 6 function as an evaporator and make the outdoor heat exchanger 8 function as a condenser.
The compressor 4, the four-way valve 5, and the outdoor heat exchanger 8 are accommodated in an outdoor unit 2. The outdoor unit 2 also accommodates a fan 9 that supplies outdoor air to the outdoor heat exchanger 8. The indoor heat exchanger 6 and the expansion device 7 are accommodated in an indoor unit 3. The indoor unit 3 also accommodates a fan (not illustrated) that supplies indoor air, which is air in an air-conditioned space, to the indoor heat exchanger 6.
The configuration of the outdoor heat exchanger 8 is now described below in detail.
The outdoor heat exchanger 8 includes the heat transfer tubes 10, and a distributor 20 that distributes refrigerant to the heat transfer tubes 10. The heat transfer tubes 10 each extend in the horizontal direction. The heat transfer tubes 10 are disposed with a predetermined spacing from each other in the up and down direction. When the outdoor heat exchanger 8 functions as an evaporator, refrigerant flowing in each heat transfer tube 10 is heated by outdoor air and evaporates. In Embodiment 1, plural heat transfer fins 15 are connected to the heat transfer tubes 10 to facilitate heat exchange between refrigerant and outdoor air.
The distributor 20 includes a body part 21, and plural flow-splitting parts 50. The body part 21 includes a first inlet 22, which is an inlet for refrigerant, and a first passage 23 in which refrigerant entering through the first inlet 22 flows upward. In Embodiment 1, refrigerant flows in the first passage 23 in the substantially vertical direction. The flow-splitting parts 50 are disposed with a predetermined spacing from each other in the up and down direction, such as the substantially vertical direction. Each flow-splitting part 50 includes a second passage 53. Each flow-splitting part 50 communicates with the first passage 23 of the body part 21 at a second inlet 54 through which refrigerant enters the second passage 53. Each flow-splitting part 50 communicates with one of the heat transfer tubes 10 at an outlet 55 through which refrigerant leaves the second passage 53. In Embodiment 1, each one flow-splitting part 50 communicates with the corresponding one heat transfer tube 10. An end portion of the heat transfer tube 10 may constitute at least a portion of the flow-splitting part 50. In other words, at least a portion of the flow-splitting part 50 may be formed integrally with the heat transfer tube 10. That is, the distributor 20 according to Embodiment 1 is a vertical-header distributor that distributes refrigerant flowing in the first passage 23, to the individual heat transfer tubes 10 from the flow-splitting parts 50 arranged in the vertical direction.
In Embodiment 1, the body part 21 is formed as a tubular component. The tubular component will hereinafter be referred to as first tubular component 24. The interior of the first tubular component 24 defines the first passage 23. The first tubular component 24 includes the first inlet 22 defined at the lower end. In Embodiment 1, each flow-splitting part 50 is formed as a tubular component. The tubular component will hereinafter be referred to as second tubular component 56. The interior of the second tubular component 56 defines the second passage 53. An end portion of the second tubular component 56 near the first passage 23 defines the second inlet 54, and an end portion of the second tubular component 56 near the heat transfer tube 10 defines the outlet 55.
The first inlet 22 may be provided at a location other than the lower end of the body part 21, such as the side of the body part 21. In this case, it may suffice that the second inlets 54 of at least two of the flow-splitting parts 50 communicate with the first passage 23 at a location above the first inlet 22.
In this regard, among the heat transfer tubes 10 each communicating with the outlet 55 of the flow-splitting part 50 whose second inlet 54 communicates with the first passage 23 at a location above the first inlet 22, at least the first one of the heat transfer tubes 10 from the top is defined as a first heat transfer tube 11. In
With the first heat transfer tube 11, the second heat transfer tube 12, the first flow-splitting part 51, and the second flow-splitting part 52 defined as described above, the second inlet 54 of the first flow-splitting part 51 communicates with the first passage 23 at a location below the second inlet 54 of the second flow-splitting part 52 that communicates with the first passage 23 at the highest location. Each second flow-splitting part 52 is disposed such that the lower the location of the second flow-splitting part 52 communicating with the first passage 23, the lower the location of the second heat transfer tube 12 with which the second flow-splitting part 52 communicates. In this regard, the second inlet 54 of the first flow-splitting part 51 may communicate with the first passage 23 at a location below the second inlet 54 of the second flow-splitting part 52 that communicates with the first passage 23 at the second highest location or lower from the top.
With the distributor 20 configured as described above, when the outdoor heat exchanger 8 functions as an evaporator, two-phase gas-liquid refrigerant flows through the first inlet 22 into the first passage 23 of the body part 21. The two-phase gas-liquid refrigerant flows upward in the first passage 23. The two-phase gas-liquid refrigerant flowing upward in the first passage 23 passes into the individual flow-splitting parts 50 sequentially, first into lower positioned flow-splitting parts 50 connected to the first passage 23, and then into higher positioned flow-splitting parts 50 connected to the first passage 23. More specifically, the two-phase gas-liquid refrigerant flowing upward in the first passage 23 first passes into each second flow-splitting part 52 that communicates with the first passage 23 at a location below the second inlet 54 of the first flow-splitting part 51. In other words, the two-phase gas-liquid refrigerant flowing upward in the first passage 23 passes into individual heat transfer tubes sequentially, beginning with lower positioned second heat transfer tubes 12. Subsequently, the two-phase gas-liquid refrigerant flowing upward in the first passage 23 passes into the first flow-splitting part 51, and then into the first heat transfer tube 11. Thereafter, the two-phase gas-liquid refrigerant flowing upward in the first passage 23 passes into the second flow-splitting part 52 that communicates with the first passage 23 at a location above the second inlet 54 of the first flow-splitting part 51, and then into the second heat transfer tube 12 that communicates with the second flow-splitting part 52 mentioned above.
A flow-combining pipe 16 is connected to an end portion of each heat transfer tube 10 opposite to the end portion near the distributor 20. The streams of refrigerant leaving the individual heat transfer tubes 10 thus combine at the flow-combining pipe 16 before flowing out of the outdoor heat exchanger 8.
In
In
Operation of the air-conditioning apparatus 1 is now described below.
Operation of the air-conditioning apparatus 1 during heating operation will be described first. High-temperature, high-pressure gas refrigerant compressed in the compressor 4 passes through the four-way valve 5 into the indoor heat exchanger 6 that functions as a condenser. Upon entering the indoor heat exchanger 6, the high-temperature, high-pressure gas refrigerant is cooled while supplying heat to indoor air, and turns into low-temperature liquid refrigerant, which then leaves the indoor heat exchanger 6. The liquid refrigerant leaving the indoor heat exchanger 6 is decompressed in the expansion device 7 into two-phase gas-liquid refrigerant at a low temperature and low pressure, which then flows into the distributor 20 of the outdoor heat exchanger 8 that functions as an evaporator. Upon entering the distributor 20 of the outdoor heat exchanger 8, the low-temperature, low-pressure two-phase gas-liquid refrigerant is distributed to the individual heat transfer tubes 10. The refrigerant flowing in the heat transfer tubes 10 evaporates upon being heated by outdoor air, and turns into low-pressure gas refrigerant before leaving the heat transfer tubes 10. Streams of low-pressure gas refrigerant leaving the individual heat transfer tubes 10 combine at the flow-combining pipe 16 before leaving the outdoor heat exchanger 8. The low-pressure gas refrigerant leaving the outdoor heat exchanger 8 passes through the four-way valve 5 before being sucked into the compressor 4, and is compressed again in the compressor 4 into high-temperature, high-pressure gas refrigerant.
Next, an explanation is made on how the air-conditioning apparatus 1 operates during cooling operation. High-temperature, high-pressure gas refrigerant compressed in the compressor 4 passes through the four-way valve 5 into the flow-combining pipe 16 of the outdoor heat exchanger 8 that functions as a condenser. Upon entering the flow-combining pipe 16 of the outdoor heat exchanger 8, the high-temperature, high-pressure gas refrigerant is distributed to the individual heat transfer tubes 10. The refrigerant flowing in the heat transfer tubes 10 condenses upon being cooled by outdoor air, and turns into low-temperature liquid refrigerant before leaving the heat transfer tubes 10. Streams of low-temperature liquid refrigerant leaving the individual heat transfer tubes 10 combine at the distributor 20 before leaving the outdoor heat exchanger 8. The liquid refrigerant leaving the outdoor heat exchanger 8 is decompressed in the expansion device 7 into two-phase gas-liquid refrigerant at a low temperature and low pressure, which then flows into the indoor heat exchanger 6 that functions as an evaporator. Upon entering the indoor heat exchanger 6, the low-temperature, low-pressure two-phase gas-liquid refrigerant evaporates while absorbing heat from indoor air, and turns into low-pressure gas refrigerant before leaving the indoor heat exchanger 6. The low-pressure gas refrigerant leaving the indoor heat exchanger 6 passes through the four-way valve 5 before being sucked into the compressor 4, and is compressed again in the compressor 4 into high-temperature, high-pressure gas refrigerant.
An explanation will be made on advantageous effects of the distributor 20 of the outdoor heat exchanger 8 according to Embodiment 1. First, with reference to
The distributor 220 according to related art includes a body part 221, and plural flow-splitting parts 250. The body part 221, which is a tubular component, includes an inlet 222 for refrigerant provided at the lower end. The body part 221 also includes a passage 223 in which refrigerant entering through the inlet 222 flows in, for example, an upward direction such as the vertical direction. The flow-splitting parts 250, which are tubular components, are disposed with a predetermined spacing from each other in the up and down direction, such as the substantially vertical direction. Each flow-splitting part 250 includes a passage 253. Each flow-splitting part 250 communicates with the passage 223 of the body part 221 at an inlet 254 through which refrigerant enters the passage 253. Each flow-splitting part 250 communicates with one of the heat transfer tubes at an outlet 255 through which refrigerant leaves the passage 253.
Each flow-splitting part 250 is disposed such that the lower the location of the flow-splitting part 250 communicating with the passage 223 of the body part 221, the lower the location of the heat transfer tube with which the flow-splitting part 250 communicates. Consequently, two-phase gas-liquid refrigerant flowing upward in the passage 223 of the body part 221 passes into the individual flow-splitting parts 250 sequentially, first into lower positioned flow-splitting parts 250 connected to the passage 223 of the body part 221, and then into higher positioned flow-splitting parts 250 connected to the passage 223 of the body part 221. That is, the two-phase gas-liquid refrigerant flowing upward in the passage 223 of the body part 221 passes into individual heat transfer tubes sequentially, first into lower positioned heat transfer tubes and then into higher positioned heat transfer tubes.
Consequently, the upward momentum of the two-phase gas-liquid refrigerant flowing upward in the passage 223 of the body part 221 decreases as the refrigerant travels upward. In this regard, the two-phase gas-liquid refrigerant is a mixture of liquid refrigerant 100 and gas refrigerant 101. A liquid reach height 102, which is the height that the liquid refrigerant 100 traveling upward in the passage 223 of the body part 221 reaches, has a positive correlation with the upward momentum of the two-phase gas-liquid refrigerant. When the upward momentum of the two-phase gas-liquid refrigerant becomes less than or equal to a certain value, gravity hinders the upward movement of the liquid refrigerant 100, which has a greater density than the gas refrigerant 101. Consequently, under conditions of low refrigerant circulation rate within the refrigeration cycle circuit such as during low-capacity operation of the air-conditioning apparatus, the liquid reach height 102 may in some cases be lower than the inlets 254 of higher positioned flow-splitting parts 250. In such a state, only the gas refrigerant 101 flows into higher positioned heat transfer tubes. The gas refrigerant 101 contributes very little to heat exchange in the evaporator in comparison to the liquid refrigerant 100. Thus, with the distributor 220 according to related art, a situation may arise in which, under conditions of low refrigerant circulation rate within the refrigeration cycle circuit such as during low-capacity operation of the air-conditioning apparatus, some heat transfer tubes receive only the gas refrigerant 101 as described above, which leads to degradation of the heat exchange performance of the evaporator.
As described above, with the outdoor heat exchanger 8 according to Embodiment 1, the first heat transfer tube 11, which is a higher positioned heat transfer tube among the heat transfer tubes 10, communicates with the first flow-splitting part 51 of the distributor 20. In other words, the first heat transfer tube 11, which tends to receive only the gas refrigerant 101 under conditions of low refrigerant circulation rate within the refrigeration cycle circuit such as during low-capacity operation of the air-conditioning apparatus 1, communicates with the first flow-splitting part 51 of the distributor 20. Further, the second inlet 54 of the first flow-splitting part 51 communicates with the first passage 23 at a location below the second inlet 54 of the second flow-splitting part 52 that communicates with the first passage 23 at the highest location. Thus, with the distributor 20 according to Embodiment 1, the second inlet 54 of the first flow-splitting part 51 can be made to communicate with the first passage 23 at a location lower than the liquid reach height 102. This makes it possible for the distributor 20 according to Embodiment 1 to supply two-phase gas-liquid refrigerant to the first heat transfer tube 11, which, in the past, would otherwise receive only the gas refrigerant 101. Therefore, the distributor 20 according to Embodiment 1 makes it possible to, under conditions of low refrigerant circulation rate within the refrigeration cycle circuit such as during low-capacity operation of the air-conditioning apparatus 1, reduce degradation of the heat exchange performance of the outdoor heat exchanger 8 that functions as an evaporator.
The liquid distribution ratio taken along the horizontal axis of
(liquid distribution ratio)=[{(the flow rate of liquid refrigerant through the flow-splitting part of interest)×(the number of flow-splitting parts)/(the flow rate of liquid refrigerant into the body part)}−1]×100
That is, if liquid refrigerant is distributed evenly to each individual flow-splitting part, the liquid distribution ratio for each flow-splitting part is 0%. For each flow-splitting part, a larger liquid distribution ratio indicates a higher flow rate of liquid refrigerant, and a smaller liquid distribution ratio indicates a lower flow rate of liquid refrigerant. A liquid distribution ratio of −100% indicates that no liquid refrigerant is distributed to the flow-splitting part.
The flow-splitting part height taken along the vertical axis of
(flow-splitting part height)={(the height of the refrigerant outlet of the flow-splitting part of interest)/(the height of the refrigerant outlet of the flow-splitting part whose refrigerant outlet is positioned highest)}×100
That is, for each flow-splitting part, the greater the value of flow-splitting part height, the higher the location of the refrigerant outlet, in other words, the higher the location of the heat transfer tube with which the flow-splitting part communicates.
As is shown in
The heating capacity taken along the horizontal axis of
(heating capacity)={(the heating capacity of the air-conditioning apparatus 1 at the time of measurement)/(the maximum specified heating capacity of the air-conditioning apparatus 1}×100
The liquid reach height taken along the vertical axis of
(liquid reach height)={(the height of the refrigerant inlet of the flow-splitting part that liquid refrigerant has reached during measurement)/(the height of the refrigerant inlet of the flow-splitting part whose refrigerant inlet is positioned highest)}×100
As is observed in
The heat exchange performance ratio taken along the vertical axis of
(heat exchange performance ratio)={(the amount of heat exchange per unit time in the outdoor heat exchanger at the time of measurement)/(the amount of heat exchange per unit time in the outdoor heat exchanger when two-phase gas-liquid refrigerant with the same gas-to-liquid ratio is introduced to all of the heat transfer tubes to provide uniform heat exchange over the entire area where the heat transfer fins of the outdoor heat exchanger are disposed)}×100
That is, the closer the heat exchange performance is to 100%, the closer the heat exchange performance of the outdoor heat exchanger is to an ideal value.
The heating capacity taken along the horizontal axis of
As illustrated in
Further, the distributor 20 according to Embodiment 1 also makes it possible to reduce degradation of the heat exchange performance of the outdoor heat exchanger 8 for regions where the heating capacity of the air-conditioning apparatus 1 is greater than or equal to 50%. More specifically, with the distributor 20 according to Embodiment 1, degradation of the heat exchange performance ratio is less than or equal to 3% for regions where the heating capacity of the air-conditioning apparatus 1 is greater than or equal to 50%. In
As described above with reference to
As is apparent from
As described above, the outdoor heat exchanger 8 according to Embodiment 1 includes the heat transfer tubes 10 disposed with a predetermined spacing from each other in the up and down direction, and the distributor 20 that distributes refrigerant to the heat transfer tubes 10. The distributor 20 includes the body part 21, and the flow-splitting parts 50. The body part 21 includes the first inlet 22 for refrigerant, and the first passage 23 in which refrigerant entering through the first inlet 22 flows upward. Each flow-splitting part 50 includes the second passage 53. Each flow-splitting part 50 communicates with the first passage 23 of the body part 21 at the second inlet 54 through which refrigerant enters the second passage 53. Each flow-splitting part 50 communicates with one of the heat transfer tubes 10 at the outlet 55 through which refrigerant leaves the second passage 53. The second inlets 54 of at least two of the flow-splitting parts 50 each communicate with the first passage 23 at a location above the first inlet 22. Among the heat transfer tubes 10 each communicating with the outlet 55 of the flow-splitting part 50 whose second inlet 54 communicates with the first passage 23 at a location above the first inlet 22, at least the first one of the heat transfer tubes 10 from the top is defined as the first heat transfer tube 11. Among the heat transfer tubes 10 each communicating with the outlet 55 of the flow-splitting part 50 whose second inlet 54 communicates with the first passage 23 at a location above the first inlet 22, the heat transfer tube 10 positioned below the first heat transfer tube 11 is defined as the second heat transfer tube 12. The flow-splitting part 50 whose outlet 55 communicates with the first heat transfer tube 11 is defined as the first flow-splitting part 51. The flow-splitting part 50 whose outlet 55 communicates with the second heat transfer tube 12 is defined as the second flow-splitting part 52. With these components defined as mentioned above, the second inlet 54 of the first flow-splitting part 51 communicates with the first passage 23 at a location below the second inlet 54 of the second flow-splitting part 52 that communicates with the first passage 23 at the highest location.
In the outdoor heat exchanger 8 according to Embodiment 1, the first heat transfer tube 11, which is a higher positioned heat transfer tube among the heat transfer tubes 10, communicates with the first passage 23 of the body part 21 at a location below a location where one or more second heat transfer tubes 12 positioned below the first heat transfer tube 11 communicate with the first passage 23. Consequently, when used as an evaporator, the outdoor heat exchanger 8 according to Embodiment 1 makes it possible to prevent the first heat transfer tube 11, which is a higher positioned heat transfer tube, from receiving no supply of liquid refrigerant during low-capacity operation of the air-conditioning apparatus 1. Thus, using the outdoor heat exchanger 8 according to Embodiment 1 as an evaporator makes it possible to maintain the heat exchange performance of the evaporator during low-capacity operation of the air-conditioning apparatus 1. In this regard, the outdoor heat exchanger 8 according to Embodiment 1 makes it possible to maintain the heat exchange performance of the evaporator during low-capacity operation of the air-conditioning apparatus 1 without reducing the effective cross-sectional area of the first passage 23. This means that using the outdoor heat exchanger 8 according to Embodiment 1 makes it possible to maintain the heat exchange performance of the evaporator also during high-capacity operation of the air-conditioning apparatus 1. Further, the distributor 20 of the outdoor heat exchanger 8 according to Embodiment 1 allows the number of components to be reduced in comparison to a distributor having within its body a passage that is divided into smaller portions by use of partition walls. As a result, the outdoor heat exchanger 8 according to Embodiment 1 allows for reduced manufacturing cost in comparison to a heat exchanger including a distributor having within its body a passage that is divided into smaller portions by use of partition walls. That is, the outdoor heat exchanger 8 according to Embodiment 1 is capable of, when functioning as an evaporator, maintaining its heat exchange performance over wide operating conditions of the air-conditioning apparatus 1 ranging from low-capacity operation to high-capacity operation, and minimizing an increase in manufacturing cost.
The air-conditioning apparatus 1 described above is only representative of one example of the air-conditioning apparatus 1 according to Embodiment 1. The foregoing description is not intended to restrict, for example, the location of the fan 9 in the outdoor unit 2 of the air-conditioning apparatus 1. The outdoor unit 2 may be of a top-flow type with airflow exiting through the top of its housing, or may be of a side-flow type with airflow exiting through the side of its housing.
In one alternative example, the air-conditioning apparatus 1 may not necessarily include only one outdoor unit 2 but may include plural indoor units 3. In another alternative example, the air-conditioning apparatus 1 may not necessarily include only one indoor heat exchanger 6, either, but may include plural indoor heat exchangers 6. In this case, each of refrigerant pipes connecting the individual indoor heat exchangers 6 with the distributor 20 of the outdoor heat exchanger 8 may be provided with the expansion device 7. In one alternative example, if the air-conditioning apparatus 1 includes plural indoor units 3, the expansion device 7 accommodated in each indoor unit 3, and the distributor 20 of the outdoor heat exchanger 8 may be connected with each other via a flow-splitting controller or other such device that adjusts how much refrigerant is to be supplied to the indoor unit 3. In another alternative example, a gas-liquid separator may be disposed between the expansion device 7, and the distributor 20 of the outdoor heat exchanger 8. The kind of refrigerant to be circulated in the refrigeration cycle circuit of the air-conditioning apparatus 1 is not particularly limited.
The heat transfer tubes 10 of the outdoor heat exchanger 8 are not limited to cylindrical heat transfer tubes but various heat transfer tubes may be used as the heat transfer tubes 10, including flat heat transfer tubes each including plural passages defined therein.
As illustrated in
As illustrated in
The second inlet 54 of the first flow-splitting part 51, and the first passage 23 of the body part 21 may communicate with each other at any location below the second inlet 54 of the second flow-splitting part 52 that communicates with the first passage 23 at the highest location. For example, as illustrated in
With the distributor 20 of the outdoor heat exchanger 8 described above, the direction in which the body part 21 extends, that is, the direction in which the first passage 23 extends is vertical. However, this is not intended to be limiting. As long as the direction of refrigerant flow through the first passage 23 has a vertically upward component, the direction in which the body part 21 extends, that is, the direction in which the first passage 23 extends may be inclined with respect to the vertical direction as illustrated in
As illustrated in
The first inlet 22 may not necessarily be provided at the lower end of the body part 21 but may be provided on the side of the body part 21. As a result, the refrigerant pipe connecting the expansion device 7 with the first inlet 22 does not need to be disposed below the body part 21. Depending on the configuration of the air-conditioning apparatus 1, it may be conceivable to arrange plural distributors 20 in the up and down direction, and connect the distributors 20 in parallel with the expansion device 7. For instance, in an attempt to improve the heat exchange performance of the outdoor heat exchanger 8, the number of flow-splitting parts 50 included in a single distributor 20 may be reduced to reduce imbalances in the distribution ratio of liquid distribution supplied to each individual heat transfer tube 10. In this case, it may be conceivable to arrange plural distributors 20 in the up and down direction. In arranging the distributors 20 in the up and down direction in this way, if the first inlet 22 is provided on the side of the body part 21, then adjacent distributors 20 can be disposed in proximity to each other in the up and down direction. This configuration makes it possible to reduce the required installation space for the distributors 20 in the up and down direction. This allows for high density mounting of the heat transfer tubes 10 of the outdoor heat exchanger 8, leading to enhanced heat transfer performance of the outdoor heat exchanger 8.
The following description of Embodiment 2 is directed to the location where the second inlet 54 of the first flow-splitting part 51 is preferably positioned if two or more second flow-splitting parts 52 are provided. Features not particularly described in Embodiment 2 below will be presumed to be similar to those in Embodiment 1, and functions or components identical to those in Embodiment 1 will be denoted by the same symbols.
The distributor 20 of the outdoor heat exchanger 8 according to Embodiment 2 includes at least two second flow-splitting parts 52. Now, the second inlet 54 of the second flow-splitting part 52 whose second inlet 54 is positioned lowest is assumed to serve as a reference. In other words, the second inlet 54 of the second flow-splitting part 52 whose second inlet 54 is positioned lowest is assumed to have a height of zero. The height, from the reference, of the second inlet 54 of the second flow-splitting part 52 whose second inlet 54 is positioned highest is defined as a first height H. The height of the second inlet 54 of the first flow-splitting part 51 from the reference is defined as a second height P. With these heights defined as described above, the distributor 20 of the outdoor heat exchanger 8 according to Embodiment 2 has a height ratio P/H of greater than 0.5 and less than 1, the height ratio P/H being obtained by dividing the second height P by the first height H. That is, 0.5<P/H<1.
The height ratio P/H is greater than 1 when the second inlet 54 of the first flow-splitting part 51 is positioned higher than the second inlet 54 of the second flow-splitting part 52 whose second inlet 54 is positioned highest. This configuration is the same as the configuration of the distributor 220 according to related art illustrated in
As can be understood from the comparison between the filled circles and the open triangles in
The following description of Embodiment 3 is directed to an exemplary configuration of the first flow-splitting part 51 for a case in which two or more first heat transfer tubes 11 are provided. Features not particularly described in Embodiment 3 below will be presumed to be similar to those in Embodiment 1 or 2, and functions or components identical to those in Embodiment 1 or 2 will be denoted by the same symbols.
The outdoor heat exchanger 8 according to Embodiment 3 includes at least two first heat transfer tubes 11.
The above-mentioned configuration of the outdoor heat exchanger 8 makes it possible to reduce the number of locations where the second inlet 54 of each flow-splitting part 50 communicates with the first passage 23 of the body part 21. This helps to reduce disturbances in the flow of refrigerant within the first passage 23, thus reducing dissipation of the kinetic energy of refrigerant within the first passage 23. This allows more liquid refrigerant to be distributed to higher positioned heat transfer tubes 10, leading to enhanced heat exchange performance of the outdoor heat exchanger 8.
The distributor 20 may be of any configuration as long as the second inlet 54 of the first flow-splitting part 51 and the second inlet 54 of the second flow-splitting part 52 have the positional relationship described above. The following description of Embodiment 4 will be directed to a specific exemplary configuration of the distributor 20. Features not particularly described in Embodiment 4 below will be presumed to be similar to those in Embodiments 1 to 3, and functions or components identical to those in Embodiments 1 to 3 will be denoted by the same symbols.
The distributor 20 according to Embodiment 4 includes a third tubular component 30. The interior of the third tubular component 30 is divided by a partition wall 34 into an upper space 31 and a lower space 32. The distributor 20 also includes a communication part 33 that provides communication between the upper space 31 and the lower space 32, at least one fourth tubular component 60 that provides communication between the lower space 32 and one of the second heat transfer tubes 12, and at least one fifth tubular component 61 that provides communication between the upper space 31 and one of the first heat transfer tubes 11. In Embodiment 4, the communication part 33 is formed as a tubular component.
In the distributor 20 configured as described above, the area in the third tubular component 30 where the lower space 32 is located serves as the body part 21. The lower space 32 serves as the first passage 23. The fourth tubular component 60 serves as the second flow-splitting part 52. The communication part 33, the area in the third tubular component 30 where the upper space 31 is located, and the fifth tubular component 61 serve as the first flow-splitting part 51. That is, the location where the communication part 33 communicates with the lower space 32 serves as the second inlet 54 of the first flow-splitting part 51.
The above-mentioned configuration of the distributor 20 makes it possible to reduce the required installation space for the distributor 20 in the up and down direction, in comparison to forming the first flow-splitting part 51 solely by the second tubular component 56. As described above, there are cases in which plural distributors 20 are arranged in the up and down direction. The above-mentioned configuration of the distributor 20 according to Embodiment 4 allows for high density mounting of the heat transfer tubes 10 of the outdoor heat exchanger 8, leading to enhanced heat transfer performance of the outdoor heat exchanger 8. In Embodiment 4, the third tubular components 30 of the distributors 20 that are adjacent to each other in the up and down direction are formed integrally with each other. In other words, the interior of a single tubular component is divided into two third tubular components 30.
The communication part 33 described above with reference to Embodiment 4 may not necessarily be a tubular component. Alternatively, the communication part 33 may be formed as described below with reference to Embodiment 5. Features not particularly described in Embodiment 5 below will be assumed to be similar to those in Embodiment 4, and functions or components identical to those in Embodiment 4 will be denoted by the same symbols.
In the distributor 20 according to Embodiment 5, the third tubular component 30 and the communication part 33 are formed integrally with each other. More specifically, the third tubular component 30 is formed by joining together two components that are U-shaped in section such that these components face each other. Beside one of the components with a U-shaped section constituting the third tubular component 30, a tubular part constituting the communication part 33 is formed integrally with this component. A wall 38 divides the third tubular component 30 and the communication part 33 from each other. The wall 38 includes a through-hole 38a, which provides communication between the interior of the communication part 33 and the lower space 32 within the third tubular component 30, and a through-hole 38b, which provides communication between the interior of the communication part 33 and the upper space 31 within the third tubular component 30. That is, the through-hole 38a serves as the second inlet 54 of the first flow-splitting part 51.
As compared with the configuration of the distributor 20 illustrated in
The distributor 20 may have various configurations as long as the second inlet 54 of the first flow-splitting part 51 and the second inlet 54 of the second flow-splitting part 52 have the positional relationship described above. Accordingly, the distributor may have the configuration as described below with reference to Embodiment 6. Features not particularly described in Embodiment 6 below will be assumed to be similar to those in Embodiments 1 to 5, and functions or components identical to those in Embodiments 1 to 5 will be denoted by the same symbols.
The distributor 20 according to Embodiment 6 includes a first plate-like component 35, a second plate-like component 36 disposed on one side of the first plate-like component 35, and a third plate-like component 37 disposed on the other side of the first plate-like component 35. The third plate-like component 37, the first plate-like component 35, and the second plate-like component 36 are stacked in this order to form the distributor 20.
More specifically, the first plate-like component 35 includes the following elements: the first inlet 22; the first passage 23; the second inlet 54 of the second flow-splitting part 52; the second passage 53 of the second flow-splitting part 52; the second inlet 54 of the first flow-splitting part 51; and the second passage 53 of the first flow-splitting part 51. The second plate-like component 36 includes the following elements: the outlet 55 of the second flow-splitting part 52 that communicates with the second inlet 54 of the second flow-splitting part 52; and the outlet 55 of the first flow-splitting part 51 that communicates with the second inlet 54 of the first flow-splitting part 51. The second heat transfer tube 12 communicates with the outlet 55 of the second flow-splitting part 52 provided in the second plate-like component 36. The first heat transfer tube 11 communicates with the outlet 55 of the first flow-splitting part 51 provided in the second plate-like component 36. The third plate-like component 37 blocks the respective lateral openings of the following elements: the first inlet 22; the first passage 23; the second inlet 54 of the second flow-splitting part 52; the second passage 53 of the second flow-splitting part 52; the second inlet 54 of the first flow-splitting part 51; and the second passage 53 of the first flow-splitting part 51. Embodiment 6 employs, as the first heat transfer tube 11 and the second heat transfer tube 12, flat heat transfer tubes each including plural passages defined therein.
The above-mentioned configuration of the distributor 20 allows the first passage 23 and the second passage 53 to be reduced in effective cross-sectional area in comparison to forming the distributor 20 by use of a tubular component. The configuration of the distributor 20 according to Embodiment 6 thus makes it possible to increase the velocity of two-phase gas-liquid refrigerant travelling upward in the first passage 23, thus allowing liquid refrigerant to reach a higher height. Further, the configuration of the distributor 20 according to Embodiment 6 makes it possible to reduce the amount of refrigerant within the distributor 20. This helps to ensure that, even if the amount of refrigerant charged into the refrigeration cycle circuit of the air-conditioning apparatus 1 is reduced for reasons such as safety or environmental regulations, degradation of the heat exchange performance of the outdoor heat exchanger 8 can be reduced.
As illustrated in
The first plate-like component 35 and the third plate-like component 37 may be formed integrally with each other by, for example, half-blanking performed on a single plate-like component. This allows for reduced number of components constituting the distributor 20, thus making it possible to simplify the structure of the distributor 20.
The following description of Embodiment 7 will be directed to an exemplary distributor 20 suited for use in an evaporator in which air velocity is greater at higher locations than at lower locations. Features not particularly described in Embodiment 7 below will be presumed to be similar to those in Embodiments 1 to 6, and functions or components identical to those in Embodiments 1 to 6 will be denoted by the same symbols.
The outdoor unit 2 according to Embodiment 7 includes an axial fan 71 disposed above the outdoor heat exchanger 8. The axial fan 71 blows out air upward from the axial fan 71. That is, the outdoor unit 2 according to Embodiment 7 is of a top-blowing type. For the outdoor unit 2 of this type, with regard to the air velocity in the outdoor heat exchanger 8, the air velocity increases gradually from a lower portion of the outdoor heat exchanger 8 toward an upper portion as illustrated in
When the outdoor heat exchanger 8 described above functions as an evaporator, it is necessary to ensure that higher positioned heat transfer tubes 10 receive more liquid refrigerant. To ensure that higher positioned heat transfer tubes 10 receive more liquid refrigerant, the effective cross-sectional area of the first passage 23 of the distributor 20 may be decreased uniformly in the up and down direction. This approach, however, leads to increased pressure loss in the first passage 23 in comparison to the pressure loss in each heat transfer tube 10. This results in lower positioned heat transfer tubes 10 receiving more liquid refrigerant than higher positioned heat transfer tubes 10. That is, with the above-mentioned approach, it is not possible to distribute liquid refrigerant to the individual heat transfer tubes 10 in accordance with air velocity distribution. This leads to degradation of the heat exchange performance of the outdoor heat exchanger 8.
Accordingly, Embodiment 7 employs the distributor 20 as illustrated in
With the distributor 20 configured as described above, the first passage 23 does not decrease in effective cross-sectional area at locations below the second inlet 54 of the first flow-splitting part 51, and decreases in cross-sectional area at locations above the second inlet 54 of the first flow-splitting part 51. This allows for reduced pressure loss in the first passage 23 at locations below the second inlet 54 of the first flow-splitting part 51. Further, at locations above the second inlet 54 of the first flow-splitting part 51, two-phase gas-liquid refrigerant can be increased in flow velocity. This makes it possible to distribute liquid refrigerant to the individual heat transfer tubes 10 in accordance with air velocity distribution, leading to enhanced heat exchange performance of the outdoor heat exchanger 8.
In some cases, the indoor unit 3 may be of a top-flow type with an axial fan disposed above the indoor heat exchanger 6. For the indoor unit 3 of this type, with regard to the airflow rate in the indoor heat exchanger 6, the airflow rate increases gradually from a lower portion of the indoor heat exchanger 6 toward an upper portion as with the air velocity distribution illustrated in each of
The indoor unit 3 in
For the indoor unit 3 of this type, the airflow rate in the indoor heat exchanger 6 increases gradually from a lower portion of the indoor heat exchanger 6 toward an upper portion as illustrated in
In some cases, the outdoor unit 2 may be of a side-flow type with a centrifugal fan disposed beside the outdoor heat exchanger 8. For the outdoor unit 2 of this type, the airflow rate in the outdoor heat exchanger 8 increases gradually from a lower portion of the outdoor heat exchanger 8 toward an upper portion as with the air velocity distribution illustrated in
For an evaporator that exchanges heat with air blown out laterally by an axial fan, it may be conceivable to distribute liquid refrigerant to individual heat transfer tubes by use of two distributors 20 disposed in the up and down direction. In such a case, each distributor 20 may be preferably configured as described below with reference to Embodiment 8. Features not particularly described in Embodiment 8 below will be presumed to be similar to those in Embodiments 1 to 7, and functions or components identical to those in Embodiments 1 to 7 will be denoted by the same symbols.
The outdoor unit 2 according to Embodiment 8 includes the axial fan 71 that blows out air laterally. That is, the axial fan 71 has a rotation axis 71a that extends in the lateral direction. Beside the axial fan 71, the outdoor heat exchanger 8 is disposed upstream or downstream of the axial fan 71 with respect to the direction of airflow. The outdoor heat exchanger 8 includes separate distributors 20, one disposed below the rotation axis 71a of the axial fan 71 and one disposed above the rotation axis 71a of the axial fan 71. The distributor 20 disposed below the rotation axis 71a of the axial fan 71 will hereinafter be referred to as distributor 41. The distributor 20 disposed above the rotation axis 71a of the axial fan 71 will be referred to as distributor 42.
For the distributor 41 disposed below the rotation axis 71a of the axial fan 71, the second inlets 54 of all of the flow-splitting parts 50 communicate with the first passage 23 at a location above the first inlet 22. For the distributor 42 disposed above the rotation axis 71a of the axial fan 71, the second inlets 54 of one or more flow-splitting parts 50 communicate with the first passage 23 at a location below the first inlet 22.
For the outdoor unit 2 configured as described above, with regard to the air velocity in the outdoor heat exchanger 8, the air velocity increases at a location near the rotation axis 71a as illustrated in
Accordingly, as described above, for the distributor 41 disposed below the rotation axis 71a of the axial fan 71, the second inlets 54 of all of the flow-splitting parts 50 communicate with the first passage 23 at a location above the first inlet 22. This configuration of the distributor 41 ensures that all of the two-phase gas-liquid refrigerant entering the first passage 23 through the first inlet 22 flows upward in the first passage 23. As a result, in the distributor 41, more liquid refrigerant can be supplied to the flow-splitting parts 50 that communicate with the first passage 23 at a higher location. That is, more liquid refrigerant can be supplied to the heat transfer tubes 10 positioned near the rotation axis 71a.
As described above, for the distributor 42 disposed above the rotation axis 71a of the axial fan 71, the second inlets 54 of one or more flow-splitting parts 50 communicate with the first passage 23 at a location below the first inlet 22. This configuration of the distributor 42 ensures that a portion of the two-phase gas-liquid refrigerant entering the first passage 23 through the first inlet 22 flows upward in the first passage 23, and another portion of the two-phase gas-liquid refrigerant flows downward in the first passage 23. At this time, gravity causes a large portion of the two-phase gas-liquid refrigerant to flow downward in the first passage 23. As a result, in the distributor 42, more liquid refrigerant can be supplied to the flow-splitting parts 50 that communicate with the first passage 23 at a location below the first inlet 22. That is, more liquid refrigerant can be supplied to the heat transfer tubes 10 positioned near the rotation axis 71a. As for the flow-splitting part 50 whose second inlet 54 communicates with the first passage 23 at a location above the first inlet 22, the distance between the first inlet 22 and the second inlet 54 is short. This ensures that the amount of liquid refrigerant supplied to the flow-splitting part 50 mentioned above does not decrease significantly.
As described above, for the outdoor heat exchanger 8 with air supplied laterally from the axial fan 71, the presence of the distributors 41 and 42 described above helps to ensure that when the outdoor heat exchanger 8 functions as an evaporator, liquid refrigerant can be distributed to the individual heat transfer tubes 10 in accordance with air velocity distribution. This allows for enhanced heat exchange performance of the outdoor heat exchanger 8.
If plural axial fans 71 that blow out air laterally are disposed in the up and down direction, then for each axial fan 71, the distributor 41 and the distributor 42 may be positioned with reference to the rotation axis 71a. This helps to ensure that when the outdoor heat exchanger 8 functions as an evaporator, liquid refrigerant can be distributed to the individual heat transfer tubes 10 in accordance with air velocity distribution, thus allowing for enhanced heat exchange performance of the outdoor heat exchanger 8.
There also exist indoor units 3 in which heat is exchanged between air supplied from an axial fan that blows out air laterally, and the indoor heat exchanger 6. In this case, it may be preferable for the indoor heat exchanger 6 to include the distributor 41 and the distributor 42. This helps to ensure that when the indoor heat exchanger 6 functions as an evaporator, liquid refrigerant can be distributed to individual heat transfer tubes in accordance with air velocity distribution, thus allowing for enhanced heat exchange performance of the indoor heat exchanger 6.
1 air-conditioning apparatus 2 outdoor unit 3 indoor unit 4 compressor 5 four-way valve 6 indoor heat exchanger 7 expansion device 8 outdoor heat exchanger 9 fan 10 heat transfer tube 11 first heat transfer tube 12 second heat transfer tube 15 heat transfer fin 16 flow-combining pipe 20 distributor 21 body part 22 first inlet 23 first passage 24 first tubular component 26 branch pipe 30 third tubular component 31 upper space 32 lower space 33 communication part 34 partition wall 35 first plate-like component 36 second plate-like component 37 third plate-like component 38 wall 38a through-hole 38b through-hole 41 distributor 42 distributor 50 flow-splitting part 51 first flow-splitting part 52 second flow-splitting part 53 second passage 54 second inlet 55 outlet 56 second tubular component 60 fourth tubular component 61 fifth tubular component 70 first plane 71 axial fan 71a rotation axis 72 centrifugal fan 73 outdoor heat exchanger 100 liquid refrigerant 101 gas refrigerant 102 liquid reach height 220 distributor (related art) 221 body part (related art) 222 inlet (related art) 223 passage (related art) 250 flow-splitting part (related art) 253 passage 254 inlet (related art) 255 outlet (related art).
| Filing Document | Filing Date | Country | Kind |
|---|---|---|---|
| PCT/JP2018/030941 | 8/22/2018 | WO |
| Publishing Document | Publishing Date | Country | Kind |
|---|---|---|---|
| WO2020/039513 | 2/27/2020 | WO | A |
| Number | Name | Date | Kind |
|---|---|---|---|
| 6804975 | Park | Oct 2004 | B2 |
| 20140338874 | Jindou et al. | Nov 2014 | A1 |
| 20150059392 | Chi | Mar 2015 | A1 |
| 20160033179 | Kim | Feb 2016 | A1 |
| 20170268790 | Yokozeki | Sep 2017 | A1 |
| Number | Date | Country |
|---|---|---|
| 3382316 | Oct 2018 | EP |
| 2013-130386 | Jul 2013 | JP |
| 2017-155990 | Sep 2017 | JP |
| 2017-211113 | Nov 2017 | JP |
| 2018-44759 | Mar 2018 | JP |
| WO-2018173356 | Nov 2017 | WO |
| WO-2018173356 | Sep 2018 | WO |
| Entry |
|---|
| Pdf is translation of foreign reference WO 2018173356 A1 (Year: 2017). |
| Pdf is translation of foreign referecne WO-2018173356-A1 (Year: 2018). |
| International Search Report and Written Opinion dated Oct. 23, 2018, received for PCT Application No. PCT/JP2018/030941, Filed on Aug. 22, 2018, 9 Pages including English Translation. |
| Number | Date | Country | |
|---|---|---|---|
| 20210231351 A1 | Jul 2021 | US |
