Patent Application
20230175747
The present disclosure relates to a heat exchanger that causes heat exchange to be performed between refrigerant and air, and also relates to a refrigeration cycle apparatus.
Heat exchangers have been known that cause heat exchange to be performed between refrigerant and air. These heat exchangers include a finless heat exchanger that has been known as not being provided with fins in the alignment direction of heat transfer tubes. Due to the absence of the fins, the finless heat exchanger does not have means to restrain the heat transfer tubes in their alignment direction. Thus, the heat transfer tubes are more likely to be bent by a thermal stress and assembly errors. This makes it difficult for the adjacent heat transfer tubes to have a uniform pitch between them. If the adjacent heat transfer tubes have a region with a smaller pitch than the other region, this causes an uneven air flow, which leads to an increase in the airflow resistance. Thus, the region with a smaller pitch is more likely to be clogged with dust and frost formed thereon.
For the purpose of solving the above problems, Patent Literature 1 discloses a heat exchanger provided with an auxiliary member. The auxiliary member has a shape like comb teeth extending between the adjacent heat transfer tubes along the alignment direction of refrigerant flow passages. With this configuration, Patent Literature 1 is intended to maintain the adjacent heat transfer tubes at a uniform pitch.
Patent Literature 1: Japanese Unexamined Patent Application Publication No. 2018-162953
The heat exchanger disclosed in Patent Literature 1 is intended to maintain the adjacent heat transfer tubes at a uniform pitch. However, due to the absence of the fins, this heat exchanger has relatively low heat transfer property of the heat transfer tubes.
The present disclosure has been achieved to solve the above problems, and it is an object of the present disclosure to provide a heat exchanger that improves heat transfer property of heat transfer tubes, while having a uniform pitch between the heat transfer tubes, and to provide a refrigeration cycle apparatus.
A heat exchanger according to one embodiment of the present disclosure includes: a first header being configured to collect and deliver refrigerant and extending in a first direction; a second header being configured to collect and deliver refrigerant, being disposed at a position facing the first header and extending in the first direction; and a plurality of heat transfer components each extending from the first header to the second header and being provided at intervals along the first direction, wherein the heat transfer components each includes a plurality of heat transfer tubes each extending from the first header to the second header and allowing refrigerant to flow in its inside; and an extension portion being provided in each of the heat transfer tubes and configured to promote heat transfer property of the heat transfer tubes, and wherein the extension portion includes a base portion extending from the heat transfer tube in a second direction in which air that flows between the plurality of heat transfer tubes flows; and a spacer portion extending from the base portion in the first direction and abutting the adjacent heat transfer component.
According to one embodiment of the present disclosure, the heat exchanger includes the heat transfer components each including the heat transfer tubes and the extension portion. The extension portion includes the spacer portion extending from the base portion in the first direction and abutting the adjacent heat transfer component. The spacer portion abuts the adjacent heat transfer components, so that the heat transfer tubes can have a uniform pitch between them. The extension portion further includes the base portion extending from the heat transfer tube in the second direction, so that this improves heat transfer property of the heat transfer tube. In this manner, the heat exchanger can improve heat transfer property of the heat transfer tubes, while having a uniform pitch between the heat transfer tubes.
Embodiments of a heat exchanger and a refrigeration cycle apparatus of the present disclosure will be described hereinafter with reference to the drawings. Note that the present disclosure is not limited by the embodiments described below. In addition, the relationship of sizes of the components in the drawings described below including
The compressor 6, the flow switching device 7, the heat exchanger 8, the expansion unit 10, and the indoor heat exchanger 11 are connected by refrigerant pipes 5 to form a refrigerant circuit 4. The compressor 6 suctions refrigerant in a low-temperature low-pressure state, compresses the sucked refrigerant into a high-temperature high-pressure state, and discharges the compressed refrigerant. The flow switching device 7 changes the flow direction of refrigerant in the refrigerant circuit 4, and is, for example, a four-way valve. For example, the heat exchanger 8 causes heat exchange to be performed between outside air and refrigerant. The heat exchanger 8 functions as a condenser during cooling operation, or functions as an evaporator during heating operation. The outdoor fan 9 is a device to deliver outside air to the heat exchanger 8.
The expansion unit 10 is a pressure reducing valve or an expansion valve to reduce the pressure of refrigerant and expand the refrigerant. The expansion unit 10 is, for example, an electronic expansion valve whose opening degree is adjusted. For example, the indoor heat exchanger 11 causes heat exchange to be performed between room air and refrigerant. The indoor heat exchanger 11 functions as an evaporator during cooling operation, or functions as a condenser during heating operation. The indoor fan 12 is a device to deliver room air to the indoor heat exchanger 11. Note that refrigerant may be water or antifreeze.
Next, the operating mode of the refrigeration cycle apparatus 1 is described. First, cooling operation is described. During cooling operation, refrigerant sucked into the compressor 6 is compressed by the compressor 6 into a high-temperature high-pressure gas state and then discharged. The refrigerant in the high-temperature high-pressure gas state discharged from the compressor 6 passes through the flow switching device 7, and flows into the heat exchanger 8 that functions as a condenser. In the heat exchanger 8, the refrigerant exchanges heat with outside air delivered by the outdoor fan 9, and condenses into liquid.
The refrigerant having condensed into a liquid state flows into the expansion unit 10, and is expanded and reduced in pressure in the expansion unit 10, so that the refrigerant is brought into a low-temperature low-pressure two-phase gas-liquid state. The refrigerant in the two-phase gas-liquid state flows into the indoor heat exchanger 11 that functions as an evaporator. In the indoor heat exchanger 11, the refrigerant exchanges heat with room air delivered by the indoor fan 12, and evaporates into gas. At this time, the room air is cooled and thus cooling is performed in the room. The refrigerant having evaporated into a low-temperature low-pressure gas state passes through the flow switching device 7 and is sucked into the compressor 6.
Next, heating operation is described, During heating operation, refrigerant sucked into the compressor 6 is compressed by the compressor 6 into a high-temperature high-pressure gas state and then discharged. The refrigerant in the high-temperature high-pressure gas state discharged from the compressor 6 passes through the flow switching device 7 and flows into the indoor heat exchanger 11 that functions as a condenser, The refrigerant flowing into the indoor heat exchanger 11 causes heat exchange to be performed between room air delivered by the indoor fan 12, and condenses into liquid in the indoor heat exchanger 11. At this time, the room air is heated and thus heating is performed in the room.
The refrigerant having condensed into a liquid state flows into the expansion unit 10, and is expanded and reduced in pressure in the expansion unit 10, so that the refrigerant is brought into a low-temperature low-pressure two-phase gas-liquid state. The refrigerant in the two-phase gas-liquid state flows into the heat exchanger 8 that functions as an evaporator. In the heat exchanger 8, the refrigerant exchanges heat with outside air delivered by the outdoor fan 9, and evaporates into gas. The refrigerant having evaporated into a low-temperature low-pressure gas state passes through the flow switching device 7 and is sucked into the compressor 6.
The first header 20 is a cuboid member extending in the first direction and allowing refrigerant to flow in its inside. The first header 20 is configured to collect and deliver refrigerant. Note that the first header 20 is not limited to being formed in a cuboid shape, but may be formed in a cylindrical shape or other shape. The first header 20 distributes refrigerant entering from the refrigerant pipe 5 to heat transfer tubes 50 of the heat transfer components 40, and also collects refrigerant having flowed out of the heat transfer tubes 50 to allow the refrigerant to flow out to the refrigerant pipe 5.
The second header 30 is disposed at a position facing the first header 20. The second header 30 is a cuboid member extending in the first direction and allowing refrigerant to flow in its inside. The second header 30 is configured to collect and deliver refrigerant. Note that the second header 30 is not limited to being formed in a cuboid shape, but may be formed in a cylindrical shape or other shape. The second header 30 distributes refrigerant entering from the refrigerant pipe 5 to the heat transfer tubes 50 of the heat transfer components 40, and also collects refrigerant having flowed out of the heat transfer tubes 50 to allow the refrigerant to flow out to the refrigerant pipe 5.
The heat transfer tube 50 is a flat tube in which a plurality of flow passages 51 are formed. The heat transfer tube 50 may be a circular tube. The heat transfer tube 50 is a member extending in the third direction from the first header 20 to the second header 30. Refrigerant having entered from the first header 20 or the second header 30 flows through the plurality of flow passages 51. The heat transfer tube 50 is made of, for example, aluminum, but may be made of a different kind of metal.
The extension portions 60 are provided to the heat transfer tube 50 and configured to promote heat transfer property of the heat transfer tube 50. The extension portions 60 extend along the second direction from the edges of opposite end portions of the heat transfer tube 50 in the second direction. The extension portions 60 extend in opposite directions away from each other. That is, two extension portions 60 are provided to one heat transfer tube 50. In
The base portion 61 is a plate-like member extending from the heat transfer tube 50 in the second direction in which air that flows between the plurality of heat transfer tubes 50 flows. The base portion 61 makes up the majority of the extension portion 60, and serves the majority of the function of promoting heat transfer property of the heat transfer tube 50.
The spacer portion 62 is a member extending from the base portion 61 in the first direction. The spacer portion 62 is a portion of the base portion 61 that is bent to extend in the first direction. In the present Embodiment 1, the spacer portion 62 is provided at the upper end portion of the base portion 61 in the third direction, and adjacent to the first header 20. Note that the spacer portion 62 may be provided at the lower end portion of the base portion 61 in the third direction, or may be provided at a different position. As illustrated in
The spacer portions 62 abut the adjacent heat transfer components 40. In the present Embodiment 1, the spacer portions 62 abut the heat transfer tubes 50 of the heat transfer components 40.
According to the present Embodiment 1, the heat exchanger 8 includes the heat transfer components 40 each including the heat transfer tube 50 and the extension portions 60, and each of the extension portions 60 includes the spacer portion 62 extending from the base portion 61 in the first direction and abutting the adjacent heat transfer member 40. The spacer portions 62 abut the adjacent heat transfer components 40, so that the heat transfer tubes 50 can have a uniform pitch between them. Each of the extension portions 60 further includes the base portion 61 extending from the heat transfer tube 50 in the second direction, so that this improves the heat transfer property of the heat transfer tube 50. In this manner, the heat exchanger 8 can improve heat transfer property of the heat transfer tubes 50, while having a uniform pitch between the heat transfer tubes 50. Furthermore, in a case where the spacer portions 62 are provided at the center of the base portions 61 in the third direction, the spacer portions 62 can further minimize the variations in the pitch between the heat transfer tubes 50 in the third direction. The heat exchanger 8 allows the heat transfer tubes 50 to have a uniform pitch between them, and thus can minimize an uneven air flow and minimize the increase in power of the outdoor fan 9.
Each of the spacer portions 62 is a portion of the base portion 61 that is bent to extend in the first direction. This brings the spacer portions 62 into surface contact with the heat transfer components 40, not into line contact with the heat transfer components 40, and thus can ensure a stable pitch between the heat transfer tubes 50. Furthermore, the spacer portions 62 abut the heat transfer tubes 50. In this manner, the spacer portions 62 abut the heat transfer tubes 50 of high rigidity, and thus can ensure a stable pitch between the heat transfer tubes 50.
A related-art heat exchanger provided with an auxiliary member has been disclosed, in which the auxiliary member has a shape like comb teeth extending between the adjacent heat transfer tubes along the alignment direction of refrigerant flow passages. However, in this related-art technique, since the auxiliary member is provided separately from the heat transfer tubes, this leads to an increase in the number of parts. Since the related-art technique involves a process of assembling the auxiliary member, this also leads to an increase in the number of manufacturing processes. In contrast to this, in the present Embodiment 1, the heat transfer tube 50 can be formed integrally with the extension portions 60. This can reduce the number of parts, and accordingly reduce the number of manufacturing processes.
As illustrated in
According to the present Embodiment 2, the spacer portions 462 are formed by bending a portion of the base portions 61, separated along the cuts 63 in the third direction, toward the first direction. With this configuration, when the heat exchanger 408 functions as an evaporator, the spacer portions 462 can receive condensed water flowing down the heat transfer tubes 50. Therefore, this can help prevent interference with drainage of the condensed water from the heat exchanger 408.
As illustrated in
According to the present Embodiment 3, each of the spacer portions 562 is a portion of the base portion 61 that is cut and raised to extend in the first direction. This decreases the area of the spacer portions 562, and results in an increased area of the base portions 61 accordingly. Therefore, the effective heat transfer area can still be maintained in the extension portions 60 in their entirety.
According to the first modification, each of the spacer portions 662 is a portion of the base portion 61 that is cut and raised to extend in the first direction. This decreases the area of the spacer portions 662, and results in an increased area of the base portions 61 accordingly. Therefore, similarly to Embodiment 3, the effective heat transfer area can still be maintained in the extension portions 60 in their entirety. The spacer portions 662 are formed by bending a portion of the base portions 61, separated along the cuts 63 in the third direction, toward the first direction. With this configuration, the spacer portions 662 can receive condensed water flowing down the heat transfer tubes 50. Therefore, this can help prevent interference with drainage of the condensed water from the heat exchanger 608.
According to the second modification, each of the spacer portions 762 is a portion of the base portion 61 that is cut and raised to extend in the first direction. This decreases the area of the spacer portions 762, and results in an increased area of the base portions 61 accordingly. Therefore, similarly to Embodiment 3, the effective heat transfer area can still be maintained in the extension portions 60 in their entirety.
According to the present Embodiment 4, two spacer portions 862 are provided and disposed at positions symmetrical to the center of the heat transfer tube 50. Due to this configuration, when the heat transfer tubes 50 are aligned with each other during the process of assembling the heat exchanger 808, even though the front and back sides of the heat transfer tube 50 are reversed, the shape of the spacer portions 862 remains unchanged regardless of orientation. Therefore, when the heat exchanger 808 is assembled, it is unnecessary to orient a plurality of heat transfer tubes 50 toward the same direction. This simplifies the process of aligning the heat transfer tubes 50 with each other. Note that the spacer portions 862 may be formed by bending a portion of the base portions 61, or may be formed by cutting and raising a portion of the base portions 61.
According to the modification, the two spacer portions 962 are provided and disposed at positions symmetrical to the center of the heat transfer tube 50. Due to this configuration, when the heat transfer tubes 50 are aligned with each other during the process of assembling the heat exchanger 908, even though the front and back sides of the heat transfer tube 50 are reversed, the shape of the spacer portions 962 remains unchanged regardless of orientation. Therefore, when the heat exchanger 908 is assembled, it is unnecessary to orient a plurality of heat transfer tubes 50 toward the same direction. This simplifies the process of aligning the heat transfer tubes 50 with each other. The spacer portions 962 are formed by bending a portion of the base portions 61, separated along the cuts 63 in the third direction, toward the first direction. With this configuration, the spacer portions 962 can receive condensed water flowing down the heat transfer tubes 50. Therefore, this can help prevent interference with drainage of the condensed water from the heat exchanger 908.
As illustrated in
According to the present Embodiment 5, the spacer portions 1062 abut the first header 20 or the second header 30. Opposite end portions of the heat transfer tubes 50 protrude from the spacer portions 1062 by a length equal to the length of insertion margin S of the heat transfer tubes 50 in the third direction. That is, when the heat transfer tubes 50 are inserted into the first header 20 or the second header 30, the spacer portions 1062 function as a guide for a worker to check the length of the insertion margin S in the third direction. The spacer portions 1062 are located at the upper end portion and the lower end portion of the base portions 61. This can help prevent the spacer portions 1062 from interfering with an air flow.
According to the modification, the spacer portions 1162 abut the first header 20 or the second header 30. Opposite end portions of the heat transfer tubes 50 protrude from the spacer portions 1162 by a length equal to the length of the insertion margin S of the heat transfer tubes 50 in the third direction. That is, when the heat transfer tubes 50 are inserted into the first header 20 or the second header 30, the spacer portions 1162 function as a guide for a worker to check the length of the insertion margin S in the third direction. The spacer portions 1162 are located at the upper end portion and the lower end portion of the base portions 61. This can help prevent the spacer portions 1162 from interfering with an air flow. Furthermore, the spacer portions 1162 are formed by bending a portion of the base portions 61, separated along the cuts 63 in the third direction, toward the first direction. With this configuration, the spacer portions 1162 can receive condensed water flowing down the heat transfer tubes 50. Therefore, this can help prevent interference with drainage of the condensed water from the heat exchanger 1108.
As illustrated in
According to the present Embodiment 6, the spacer portions 1262 that may slightly interfere with an air flow are located at equal intervals along the third direction. This can result in equal pressure loss in the third direction in its entirety. Thus, an uneven air flow can be minimized in the third direction in its entirety. Therefore, the increase in power of the outdoor fan 9 can be minimized.
According to the modification, a plurality of the spacer portions 1362 are provided, in which the number of the spacer portions 1362 is greater on the downstream side of the heat transfer tubes 50 than on the upstream side thereof. When the heat exchanger 1308 functions as an evaporator, there is a higher probability that frost is formed on the upstream side of the heat transfer tubes 50 compared to on the downstream side thereof, In the modification, a plurality of the spacer portions 1362 are provided, in which the number of the spacer portions 1362 is greater on the downstream side of the heat transfer tubes 50 than that on the upstream side thereof. Thus, the amount of frost accumulating on the spacer portions 1362 in their entirety can be reduced.
1: refrigeration cycle apparatus 2: outdoor unit, 3: indoor unit, 4: refrigerant circuit, 5: refrigerant pipe, 6: compressor, 7: flow switching device, 8: heat exchanger, 9: outdoor fan, 10: expansion unit, 11: indoor heat exchanger, 12: indoor fan, 20: first header, 30: second header, 40: heat transfer member, 50: heat transfer tube, 51: flow passage, 60: extension portion, 61: base portion, 62: spacer portion, 63: cut, 64: hole, 108: heat exchanger, 208: heat exchanger, 262: spacer portion, 308: heat exchanger, 362: spacer portion, 362a: protruding portion, 408: heat exchanger, 462: spacer portion, 508: heat exchanger, 562: spacer portion, 608: heat exchanger, 662: spacer portion, 708: heat exchanger, 762: spacer portion, 808: heat exchanger, 862: spacer portion, 908: heat exchanger, 962: spacer portion, 1008: heat exchanger, 1062: spacer portion, 1108: heat exchanger, 1162: spacer portion, 1208: heat exchanger, 1262: spacer portion, 1308: heat exchanger, 1362: spacer portion
| Filing Document | Filing Date | Country | Kind |
|---|---|---|---|
| PCT/JP2020/021578 | 6/1/2020 | WO |
