The present disclosure relates to an air conditioner.
PATENT LITERATURE 1 discloses an air conditioner including a heat exchanger and a refrigerant flow divider configured to divide a liquid refrigerant into a plurality of paths and flow the refrigerant into the heat exchanger. The refrigerant flow divider includes a flow divider body having an internal branching flow path, and a plurality of refrigerant tubes connected to a lower surface of the flow divider body. The refrigerant tubes are each connected to a liquid header of the heat exchanger.
The present disclosure provides an air conditioner including:
a heat exchanger;
a refrigerant flow divider configured to divide and flow a liquid refrigerant to the heat exchanger; and
a case including a bottom plate and accommodating the heat exchanger and the refrigerant flow divider; in which
the bottom plate is provided with a first drain unit having a first opening for drainage,
the refrigerant flow divider includes a flow divider body having a branching flow path, and a plurality of refrigerant tubes that is projecting downward from a lower surface of the flow divider body, is then bent, and is connected to the heat exchanger at a position above the lower surface, and
all the refrigerant tubes have lowermost ends positioned to be vertically overlapped with the first drain unit.
Description will be made hereinafter to embodiments of the present disclosure.
An air conditioner 1 includes an outdoor unit 2 disposed outdoors and an indoor unit 3 disposed indoors. The outdoor unit 2 and the indoor unit 3 are connected to each other by a connection pipe. The air conditioner 1 includes a refrigerant circuit 4 configured to execute vapor compression refrigeration cycle operation. The refrigerant circuit 4 is provided with an indoor heat exchanger 11, a compressor 12, an oil separator 13, an outdoor heat exchanger 14, an expansion valve (expansion mechanism) 15, an accumulator 16, a four-way switching valve 17, and the like, which are connected by a refrigerant pipe 10. The refrigerant pipe 10 includes a liquid pipe 10L and a gas pipe 10G.
The indoor heat exchanger 11 is configured to execute heat exchange between a refrigerant and indoor air, and is provided in the indoor unit 3. Examples of the indoor heat exchanger 11 include a fin-and-tube heat exchanger of a cross-fin type and a heat exchanger of a microchannel type. The indoor heat exchanger 11 is provided therearound with an indoor fan (not depicted) configured to send indoor air to the indoor heat exchanger 11.
The compressor 12, the oil separator 13, the outdoor heat exchanger 14, the expansion valve 15, the accumulator 16, and the four-way switching valve 17 are provided in the outdoor unit 2.
The compressor 12 is configured to compress a refrigerant sucked from a suction port and discharge the compressed refrigerant from a discharge port. Examples of the compressor 12 include various compressors such as a scroll compressor.
The oil separator 13 is configured to separate lubricant from fluid mixture that contains the lubricant and a refrigerant and is discharged from the compressor 12. The refrigerant thus separated is sent to the four-way switching valve 17 whereas the lubricant is returned to the compressor 12.
The outdoor heat exchanger 14 is configured to execute heat exchange between a refrigerant and outdoor air. The outdoor heat exchanger 14 according to one or more embodiments is of the microchannel type. The outdoor heat exchanger 14 is provided therearound with an outdoor fan 18 configured to send outdoor air to the outdoor heat exchanger 14. The outdoor heat exchanger 14 has a liquid side end provided with a refrigerant flow divider 19 including a capillary tube 37.
The expansion valve 15 is disposed between the outdoor heat exchanger 14 and the indoor heat exchanger 11 in the refrigerant circuit 4, and expands an incoming refrigerant to be decompressed to have predetermined pressure. Examples of the expansion valve 15 include an electronic expansion valve having a variable opening degree.
The accumulator 16 is configured to separate an incoming refrigerant into a gas refrigerant and a liquid refrigerant, and is disposed between the suction port of the compressor 12 and the four-way switching valve 17 in the refrigerant circuit 4. The gas refrigerant thus separated at the accumulator 16 is sucked into the compressor 12.
The four-way switching valve 17 is configured to be switchable between a first state indicated by solid lines in
When the air conditioner 1 executes cooling operation, the outdoor heat exchanger 14 functions as a refrigerant condenser and the indoor heat exchanger 11 functions as a refrigerant evaporator. A gas refrigerant discharged from the compressor 12 condenses at the outdoor heat exchanger 14, is then decompressed at the expansion valve 15, and evaporates at the indoor heat exchanger 11 to be sucked into the compressor 12. Also during defrosting operation of removing frost formed on the outdoor heat exchanger 14 or the like using heating operation, the outdoor heat exchanger 14 functions as a refrigerant condenser and the indoor heat exchanger 11 functions as a refrigerant evaporator, as in cooling operation.
When the air conditioner 1 executes heating operation, the outdoor heat exchanger 14 functions as a refrigerant evaporator and the indoor heat exchanger 11 functions as a refrigerant condenser. A gas refrigerant discharged from the compressor 12 condenses at the indoor heat exchanger 11, is then decompressed at the expansion valve 15, and evaporates at the outdoor heat exchanger 14 to be sucked into the compressor 12.
The following description may include expressions such as “up”, “down”, “left”, “right”, “front (before)”, and “rear (behind)”, for indication of directions and positions. These expressions follow directions indicated by arrows in
As depicted in
The outdoor heat exchanger 14 according to one or more embodiments faces four surfaces, namely, a left side surface, a rear surface, a right side surface, and a front surface of the case 40 in a planar view (top view). Part of the outdoor heat exchanger 14 facing the front surface of the case 40 is shorter than a length of the case 40 in lateral directions X to face only end portions in the lateral directions X of the front surface of the case 40. The surfaces of the case 40 facing the outdoor heat exchanger 14 are each provided with an opening 40a for air supply. The outdoor heat exchanger 14 includes a pair of headers 21 and 22, and a heat exchanger body 23. The pair of headers 21 and 22 and the heat exchanger body 23 are made of aluminum or an aluminum alloy.
The pair of headers 21 and 22 are disposed at respective ends of the heat exchanger body 23 in a planar view. The header 21 is a liquid header configured to allow a liquid refrigerant (gas-liquid two-phase refrigerant) to flow therein. The header 22 is a gas header configured to allow a gas refrigerant to flow therein. The liquid header 21 and the gas header 22 are disposed to have longitudinal directions aligned to vertical directions Z.
As depicted in
The heat exchanger body 23 is configured to execute heat exchange between a refrigerant flowing inside and air. As depicted in
Examples of the heat transfer tubes 26 include a flat porous tube having a plurality of holes serving as refrigerant flow paths and aligned horizontally. The plurality of fins 27 is aligned longitudinally along the heat transfer tubes 26. The refrigerant unidirectionally flows from the liquid header 21 to the gas header 22 through the heat exchanger body 23, or unidirectionally flows from the gas header 22 to the liquid header 21 through the heat exchanger body 23.
The heat exchanger body 23 exemplarily depicted in
The liquid header 21 is connected with a plurality of connecting tubes 35A to 35K. The connecting tubes 35A to 35K are provided correspondingly to the flow paths 33A to 33K. The connecting tubes 35A to 35K are connected with capillary tubes 37A to 37K of the refrigerant flow divider 19.
During heating operation, a liquid refrigerant obtained at the refrigerant flow divider 19 flows through the capillary tubes 37A to 37K and the connecting tubes 35A to 35K, flows into the flow paths 33A to 33K in the liquid header 21, and flows through one or a plurality of heat transfer tubes 26 connected to the flow paths 33A to 33K to reach the gas header 22. In contrast, during cooling operation or defrosting operation, the refrigerant divided at the gas header 22 into the heat transfer tubes 26 flows into the flow paths 33A to 33K of the liquid header 21, and flows from the flow paths 33A to 33K to the capillary tubes 37A to 37K to join at the flow divider body 50.
The gas header 22 has an interior not zoned but extending continuously across all the heat exchange units 31A to 31K. The refrigerant flowing from the single gas pipe 24 into the gas header 22 is accordingly divided into all the heat transfer tubes 26, and the refrigerant flowing from all the heat transfer tubes 26 into the gas header 22 is joined at the gas header 22 to flow into the single gas pipe 24.
The heat exchange units 31A to 31K, the flow paths 33A to 33K in the liquid header 21, the connecting tubes 35A to 35K, and the capillary tubes 37A to 37K are equal in the number thereof, and
As depicted in
The flow divider body 50 has a cylindrical shape having a central axis disposed along the vertical directions Z. The flow divider body 50 is provided therein with the branching flow path.
The flow divider body 50 has an upper surface (a first end surface in the vertical directions Z) 50a connected with the single main tube 51. The main tube 51 extends upward from the upper surface 50a of the flow divider body 50. The main tube 51 is connected to the expansion valve 15 (see
The flow divider body 50 has a lower surface (a second end surface in the vertical directions Z) 50b connected with the plurality of capillary tubes 37. The capillary tubes 37 project downward from the lower surface 50b of the flow divider body 50, are then bent and extend upward to reach above the lower surface 50b of the flow divider body 50.
Described below are some of the capillary tubes 37 connected to the lower surface 50b of the flow divider body 50 and connected to the liquid header 21 of the outdoor heat exchanger 14 at a position above the lower surface 50b of the flow divider body 50, specifically, the capillary tubes 37C to 37K other than the capillary tubes 37A and 37B connected to the lowermost connecting tube 35A and the second lowermost connecting tube 35B in
Hereinafter, the capillary tubes 37 and the connecting tubes 35 projecting from the liquid header 21 will be collectively and simply called “refrigerant tubes”. The refrigerant tubes can be categorized into the following three types:
(1) As denoted by reference sign A in
(2) As denoted by reference sign B in
(3) As denoted by reference sign C in
As depicted in
Specifically, as depicted in
As depicted in
As depicted in
Accordingly, the lowermost ends A3, B2b, and C2 of the first to third refrigerant tubes A to C are positioned to be vertically overlapped with the first opening 41a. In other words, the first opening 41a is sized to include lower regions of the lowermost ends A3, B2b, and C2 of the first refrigerant tube A, the second refrigerant tube B, and the third refrigerant tube C.
During heating operation, a condensed liquid refrigerant flows in the main tube 51 of the refrigerant flow divider 19 and is divided at the flow divider body 50 to flow in the refrigerant tubes A, B, and C. The refrigerant flowing in the refrigerant tubes A, B, and C is decompressed to be decreased in temperature and comes into a gas-liquid two-phase refrigerant lower in temperature than outdoor air. Outdoor air around the refrigerant tubes A, B, and C is cooled in this case, so that condensate or frost may be formed on the refrigerant tubes A, B, and C. While defrosting operation is executed to remove frost formed on the refrigerant tubes A, B, and C, the frost melts and water may adhere to the refrigerant tubes A, B, and C.
In such a case where water adheres to the refrigerant tubes A, B, and C, the water flows downward along the refrigerant tubes A, B, and C and drops from the lowermost ends A3, B2b, and C2 of the refrigerant tubes A, B, and C. The lowermost ends A3, B2b, and C2 of the refrigerant tubes A, B, and C are positioned to be vertically overlapped with the first opening 41a in one or more embodiments. Water drops from the lowermost ends A3, B2b, and C2 of the refrigerant tubes A, B, and C is thus exhausted outside from the first opening 41a. This inhibits water from freezing on the bottom plate 41 and an ice-up phenomenon of growing ice upward.
As depicted in
The second slant portion B3 is slant to have a first end positioned adjacent to the first slant portion B2 and at a lower level, and a second end positioned adjacent to the third slant portion B4 and at a higher level. The third slant portion B4 is slant to have a first end positioned adjacent to the second slant portion B3 and at a lower level, and a second end positioned far from the second slant portion B3 and at a higher level. As depicted in
As depicted in
The second slant portion C3 is slant to have a first end positioned adjacent to the horizontal portion C2 and at a lower level, and a second end positioned adjacent to the third slant portion C4 and at a higher level. The third slant portion C4 is slant to have a first end positioned adjacent to the second slant portion C3 and at a lower level, and a second end positioned far from the second slant portion C3 and at a higher level. As depicted in
As depicted in
As depicted in
As depicted in
As depicted in
Water flowing from the third slant portions B4 and C4 to the second slant portions B3 and C3 beyond the boundaries B6 and C6, condensate adhering to the second slant portions B3 and C3, and the like flow further downward along the second slant portions B3 and C3, respectively. As depicted in
As depicted in
The first drain unit 53 having the first opening 41a and the second drain unit 54 having the second opening 41b (hereinafter simply referred to as the “opening 41a or 41b” or the “drain unit 53 or 54”) can be configured as depicted in
Alternatively, at the first slant portion B2 of the second refrigerant tube B, the first end B2a adjacent to the first connecting portion B1 may be positioned at a lower level and the second end B2b adjacent to the second slant portion B2 may be positioned at a higher level. In this case, the first end B2a of the first slant portion B3 constitutes the lowermost end of the second refrigerant tube B, so that the first end B2a of the first slant portion B2 is positioned to be vertically overlapped with the first opening 41a.
The outdoor heat exchanger 14 according to one or more embodiments faces the four side surfaces of the case 40. The outdoor heat exchanger 14 may alternatively have a substantially U shape in a planar view to face three side surfaces of the case 40.
Although the refrigerant flow divider 19 according to one or more embodiments is disposed diagonally backward left with respect to the liquid header 21, the refrigerant flow divider 19 may alternatively be disposed laterally to the liquid header 21 in the lateral directions X.
The above embodiments describe the air conditioner 1 assuming that the arrow Z indicates the vertical directions, the arrow Y indicates the front and rear directions, and the arrow X indicates the lateral directions. However, the present disclosure should not be limited to this case, and the arrow X may indicate the front and rear directions and the arrow Y may indicate the lateral directions.
The heat exchanger and the refrigerant tubes may have frost formed thereon during heating operation under a condition with low outdoor temperature. The air conditioner thus executes the defrosting operation while periodically flowing a refrigerant having high temperature to the heat exchanger in order to melt the frost. However, if water obtained by melting the frost at the refrigerant flow divider accumulates on a bottom plate of the air conditioner executing defrosting operation, the water may freeze during repeated heating operation and cause a phenomenon of gradually growing upward (an ice-up phenomenon).
Therefore, one or more embodiments of the present disclosure provide an air conditioner configured to appropriately exhaust outside, water adhering to a refrigerant tube of a refrigerant flow divider.
(1) The air conditioner 1 according to the above embodiments includes the outdoor heat exchanger 14, the refrigerant flow divider 19 configured to divide and flow a liquid refrigerant to the outdoor heat exchanger 14, and the case 40 having the bottom plate 41 and accommodating the outdoor heat exchanger 14 and the refrigerant flow divider 19. The bottom plate 41 is provided with the first drain unit 53 having the first opening 41a for drainage. The refrigerant flow divider 19 includes the flow divider body 50 having the branching flow path, and the plurality of refrigerant tubes A, B, and C projecting downward from the lower surface 50b of the flow divider body 50, then bent, and connected to the outdoor heat exchanger 14 at a position above the lower surface 50b. The lowermost ends A3, B2b, and C2 of all the refrigerant tubes A, B, and C are positioned to be vertically overlapped with the first drain unit 53. Accordingly, even when water adhering to the surfaces of the refrigerant tubes A, B, and C drops from the lowermost ends A3, B2b, and C2 of the refrigerant tubes A, B, and C, respectively, the water can be exhausted outside the case 40 from the first drain unit 53.
(2) The lowermost ends A3, B2b, and C2 of the refrigerant tubes A, B, and C according to the above embodiments are positioned to be vertically overlapped with the first opening 41a. Accordingly, when water adhering to the surfaces of the refrigerant tubes A, B, and C drops from the lowermost ends A3, B2b, and C2 of the refrigerant tubes A, B, and C, respectively, the water can be exhausted outside the case 40 directly from the first opening 41a.
(3) As depicted in
(4) The first slant portion B2 according to the above embodiments is slant with respect to the horizontal direction by 15 or more degrees. Accordingly, water is likely to flow to the lower end portion of the first slant portion B2, and can drop from the lowermost end B2b of the refrigerant tube B.
(5) As depicted in
(6) As depicted in
(7) As depicted in
(8) The second slant portions B3 and C3 and the third slant portions B4 and C4 according to the above embodiments are slant with respect to the horizontal direction by 15 or more degrees. Accordingly, water adhering to the second slant portions B3 and C3 and the third slant portions B4 and C4 can flow to the lower end portions of the second slant portions B3 and C3 and the third slant portions B4 and C4, respectively.
(9) The refrigerant tubes A, B, and C according to the above embodiments include the second connecting portions A7, B7, and C7 connected to the liquid header 21 of the outdoor heat exchanger 14, and at least one of the refrigerant tubes A, B, and C is disposed vertically from the second connecting portion A7, B7, or C7 to the lowermost end A3, B2b, or C2, or is slant downward from the second connecting portion A7, B7, or C7 toward the lowermost end A3, B2b, or C2, respectively. Accordingly, water adhering to the refrigerant tube A, B, or C between the second connecting portion A7, B7, or C7 and the lowermost end A3, B2b, or C2 is likely to flow to the lowermost end A3, B2b, or C2 along the refrigerant tube A, B, or C, respectively.
(10) The first end and the second end of the outdoor heat exchanger 14 according to the above embodiments are disposed apart from each other, the first end of the outdoor heat exchanger 14 is connected with the refrigerant flow divider 19, and the second end of the outdoor heat exchanger 14 is connected with the gas header (gas side pipe) 22. When both the refrigerant flow divider 19 and the gas header 22 are connected to the first end of the outdoor heat exchanger 14, a high-temperature refrigerant flowing in the gas header 22 warms the periphery of the refrigerant flow divider 19 to be less likely to cause freezing of water adhering to the refrigerant flow divider 19 and freezing of water dropping to the bottom plate 41. When the refrigerant flow divider 19 and the gas header 22 are disposed separately at the first end and the second end of the outdoor heat exchanger 14 as in one or more embodiments, temperature around the refrigerant flow divider 19 is further decreased to be likely to cause freezing of water. It is accordingly more useful to configure the refrigerant tubes A, B, and C of the refrigerant flow divider 19 as described above.
Although the disclosure has been described with respect to only a limited number of embodiments, those skilled in the art, having benefit of this disclosure, will appreciate that various other embodiments may be devised without departing from the scope of the present disclosure. Accordingly, the scope of the disclosure should be limited only by the attached claims.
Number | Date | Country | Kind |
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2019-205872 | Nov 2019 | JP | national |
Number | Date | Country | |
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Parent | PCT/JP2020/039501 | Oct 2020 | US |
Child | 17739977 | US |