This application is a U.S. national stage application of International Patent Application No. PCT/JP2018/032001 filed on Aug. 29, 2018, the disclosure of which is incorporated herein by reference.
The present invention relates to an outdoor unit and an air conditioner, the outdoor unit including a heat dissipator.
An outdoor unit disclosed in Patent Literature 1 includes: a housing with an outlet formed on a front panel; a heat exchanger, a compressor, and a blower provided in the housing; a control substrate provided in the housing and controlling the operation of the compressor and the blower; an electric component provided on the control substrate; and a heat dissipator for dissipating heat generated by the electric component. The outdoor unit further includes a partition board that partitions the space in the housing into a blower chamber and a compressor chamber, the blower chamber being a space where the blower is arranged, and the compressor chamber being a space where the compressor is arranged. The heat dissipator includes a base thermally connected to the electric component, and a plurality of fins provided on the base. An air guide is provided on the side of tips of the plurality of fins, and the space surrounded by the base, the plurality of fins, and the air guide forms an air passage. According to the outdoor unit disclosed in Patent Literature 1, even when the heat dissipator is provided near a blower fan having a relatively small amount of ventilation, the entire heat dissipator is cooled efficiently by allowing air to flow through the air passage formed in the heat dissipator.
However, when a bell mouth is provided around the outlet of the housing of the outdoor unit disclosed in Patent Literature 1, a closed space surrounded by an outer peripheral surface of the bell mouth, an inner surface of the front panel, and the partition board is formed in the housing. The bell mouth is an annular member that projects from an annular wall surface forming the outlet into the housing so as to reduce a pressure loss when the air having passed through the machine heat exchanger and flowed into an air blowing chamber is discharged to the outside of the air blowing chamber through the outlet. In this closed space, the pressure tends to be high because the air flow is more stagnant therein than in the space outside the closed space. Therefore, when leeward end surfaces of the fins lie in the closed space, the air having entered the air passage formed between the adjacent fins from windward end surfaces of the fins flows toward the tips of the fins, that is, ends of the fins on the side opposite to the side of the base, before reaching the leeward end surfaces of the fins. Such a change in the direction of flow of the air having entered the air passage causes a decrease in the velocity of flow of the air at the leeward end surfaces of the fins, so that the cooling capacity of the heat dissipator cannot be sufficiently achieved.
The present invention has been made in view of the above, and an object of the present invention is to provide an outdoor unit in which the cooling capacity of a heat dissipator can be improved even when a bell mouth is provided in a housing.
An outdoor unit according to an aspect of the present invention includes a housing that includes a front panel having an outlet for an airflow, a back panel facing the front panel, a left side panel, a right side panel facing the left side panel, a bottom panel, and a top panel facing the bottom panel. The outdoor unit further includes a bell mouth that has an annular shape, is provided on the front panel, and projects from a rim of a circular opening forming the outlet, a control substrate that is provided in the housing and provided with an electric component, and a heat dissipator that dissipates heat generated by the electric component. A windward end surface and a leeward end surface of the heat dissipator are, when viewed from above, placed in a region between a virtual surface and the back panel, the virtual surface being a virtual surface that is in contact with an end of the bell mouth on a side of the back panel and is parallel to an inner surface of the front panel.
The outdoor unit according to the present invention has an effect that the cooling capacity of the heat dissipator can be improved even when the bell mouth is provided in the housing.
An outdoor unit and an air conditioner according to embodiments of the present invention will now be described in detail with reference to the drawings. Note that the present invention is not limited to the embodiments.
First, an overview of the configuration of an outdoor unit 1-1 according to a first embodiment of the present invention will be described with reference to
The housing 2 includes a front panel 3 that forms a front surface of the housing 2, a back panel 8 that faces the front panel 3 and forms a back surface of the housing 2, a left side panel 4 that forms a side surface on the left side of the housing 2 when the housing 2 is viewed from the front, a right side panel 5 that faces the left side panel 4, a bottom panel 6 that forms a bottom surface of the housing 2, and a top panel 7 that faces the bottom panel 6. Note that the front panel 3 and the left side panel 4 may be formed by one component.
An inlet 4a is formed on the left side panel 4. An inlet 8a is formed on the back panel 8. The inlet 4a and the inlet 8a are for taking air from the outside of the housing 2 into the housing 2.
An outlet 31 of a circular shape is formed on the front panel 3. The outlet 31 is an opening for discharging the air taken into the housing 2 to the outside of the housing 2. The bell mouth 9 is provided on a wall surface 3a having an annular shape and forming the outlet 31. The bell mouth 9 is an annular member projecting from the wall surface 3a into the housing 2.
Inside the housing 2, the blower 13 is arranged within a region that is obtained by projecting an inner edge of the bell mouth 9 from the front panel 3 of the housing 2 toward the back panel 8 thereof. The blower 13 includes an impeller 13a and a motor 13b that is a power source for the impeller 13a. When the motor 13b of the blower 13 is driven to cause the impeller 13a of the blower 13 to rotate, air is taken into a blower chamber 11 of the housing 2 through the inlets 4a and 8a. The air taken into the blower chamber 11 is discharged to the outside of the housing 2 through the outlet 31. In
The partition board 10 is a member that partitions the space in the housing 2 into the blower chamber 11 and a compressor chamber 12, the blower chamber 11 being a space where the blower 13 is arranged, and the compressor chamber 12 being a space where the compressor 14 is arranged. The blower chamber 11 is the space surrounded by the front panel 3, the left side panel 4, the bottom panel 6, the top panel 7, the back panel 8, and the partition board 10. The compressor chamber 12 is the space surrounded by the front panel 3, the right side panel 5, the bottom panel 6, the electric component box 15, the back panel 8, and the partition board 10. When the outdoor unit 1-1 is viewed from the front, for example, the partition board 10 extends from the bottom panel 6 toward the top panel 7 and comes into contact with a lower surface of the electric component box 15 before reaching the top panel 7.
The compressor chamber 12 is the space surrounded by the partition board 10 and the right side panel 5. The compressor chamber 12 is provided with the compressor 14 for compressing the refrigerant. The compressor 14 is connected to a plurality of pipes (not shown) included in the heat exchanger 22, and the refrigerant compressed by the compressor 14 is sent to the pipes. When air passes through the heat exchanger 22, heat exchange occurs between the refrigerant flowing through the pipes and the heat exchanger 22.
The heat exchanger 22 is provided inside the housing 2 so as to cover the inlets 4a and 8a. The heat exchanger 22 is provided in the blower chamber 11 and faces the inside of each of the back panel 8 and the left side panel 4 of the housing 2. When the outdoor unit 1-1 is viewed from above, for example, the heat exchanger 22 has an L-shape extending from the left side panel 4 toward the back panel 8. The heat exchanger 22 includes a plurality of heat dissipating fins (not shown) arranged apart from one another, and the plurality of pipes (not shown) provided to pass through the plurality of heat dissipating fins and allowing the refrigerant to flow through the pipes.
The electric component box 15 is provided above the compressor chamber 12. The electric component box 15 is provided in a space formed between an upper end of the partition board 10 and the top panel 7. The electric component box 15 is for controlling components of the air conditioner, and is arranged over the blower chamber 11 and the compressor chamber 12.
The electric component box 15 houses the control substrate 16 on which a plurality of electric components 17 is provided. The control substrate 16 is a plate-shaped member extending from the right side panel 5 toward the left side panel 4. The electric components 17 are provided on a substrate surface 16a of the control substrate 16. The substrate surface 16a is a surface of the control substrate 16 on the side of the bottom panel 6. The electric component 17 is, for example, a semiconductor element, a reactor, or the like constituting an inverter circuit that converts direct current power into alternating current power and drives at least one of the compressor 14 and the blower 13. The electric component 17 is not limited to the semiconductor element or the reactor forming the inverter circuit and may be, for example, a resistor for voltage detection, a smoothing capacitor, or a semiconductor element forming a converter circuit that converts alternating current power supplied from a commercial power source into direct current power and outputs it to an inverter circuit.
Each of the plurality of electric components 17 is in contact with a heat dissipator 18-1 as illustrated in
Next, a configuration of the heat dissipator 18-1 will be described with reference to
As illustrated in
An upper surface 19a of the base 19 is in contact with the electric components 17 illustrated in
Each of the plurality of fins 21 includes heat dissipating surfaces 21a. The heat dissipating surface 21a is a surface facing the adjacent one of the fins 21. The heat dissipating surface 21a has a rectangular shape, for example. Note that the shape of the fin 21 is not limited to the rectangle as long as the fin 21 can dissipate the heat, which is transferred from the base 19 to the fin 21, to the air. The heat dissipating surfaces 21a are parallel to the left side panel 4 and the right side panel 5 illustrated in
One end surface of each of the plurality of fins 21 in the Z axis direction forms a windward end surface 21c. A plurality of the windward end surfaces 21c corresponds to a windward end surface of the heat dissipator 18-1. An inlet 24 for allowing air to flow into the air passage 23 is formed in the gap between adjacent ones of the windward end surfaces 21c.
Another end surface of each of the plurality of fins 21 in the Z axis direction forms a leeward end surface 21d. A plurality of the leeward end surfaces 21d corresponds to a leeward end surface of the heat dissipator 18-1. An outlet 25 for discharging air passing through the air passage 23 is formed in the gap between the adjacent ones of the leeward end surfaces 21d.
As illustrated in
Next, the flow of air in the heat dissipator 18-1 will be described. Note that for the purpose of facilitating the understanding of an effect of the heat dissipator 18-1, a configuration of a heat dissipator according to a comparison example will be described first, and then the flow of air in the heat dissipator 18-1 according to the first embodiment will be described.
The flow of air in the heat dissipator 18A will be described. When the airflow AF is generated by the rotation of the blower 13, the air on the windward side of the heat dissipator 18A flows into the air passage formed by fins 21A from an inlet 24A of the heat dissipator 18A. Here, because the closed space F is formed inside the housing of the outdoor unit 1A, the flow of the air is stagnant in the closed space F. When the flow of the air becomes stagnant in the closed space F, the pressure in the closed space F tends to be higher than the pressure in the space outside the closed space F. Therefore, when the outlet 25A of the heat dissipator 18A lies in the closed space F, air A that has entered the air passage of the fins 21A flows toward ends 21A1 of the fins before reaching the outlet 25A of the heat dissipator 18A. Such a change in the direction of flow of the air A having entered the air passage causes a decrease in the velocity of flow of the air A at the outlet 25A of the heat dissipator 18A, so that the cooling capacity of the heat dissipator 18A cannot be sufficiently achieved.
On the other hand, in the heat dissipator 18-1 according to the first embodiment, the leeward end surfaces 21d are arranged on the windward side relative to the virtual surface S, so that the retention of the air as in the closed space F does not occur in the space between the leeward end surfaces 21d and the virtual surface S. Accordingly, the air A that has entered the air passage 23 of the fins 21 is discharged from the outlet 25 of the heat dissipator 18-1. As a result, the velocity of flow of the air A passing through the air passage 23 of the fins 21 is increased as compared to that through the heat dissipator 18A illustrated in
Moreover, according to the outdoor unit 1-1 of the first embodiment, the cooling efficiency of the heat dissipator 18-1 is improved so that the electric components 17 provided on the control substrate 16 are efficiently cooled. The efficient cooling of the electric components 17 can extend the life of the control substrate 16 and the electric components 17. The outdoor unit 1-1 according to the first embodiment can also extend the life of another component not in contact with the heat dissipator 18-1. For example, in a case where the other component is an electrolytic capacitor, the electrolytic capacitor is a component that is easily affected by the ambient temperature because it contains an electrolyte solution. Being affected by the ambient temperature, the life of the electrolytic capacitor is roughly doubled when the ambient temperature drops by 10° C. The efficient cooling of the electric components 17 can prevent or reduce an increase in the ambient temperature as well. Preventing or reducing the increase in the ambient temperature can prevent or reduce the influence of heat on the other component not in contact with the heat dissipator 18-1, and can significantly extend the life thereof.
When the electric components 17 are downsized, the heat dissipation area of the electric components 17 is reduced, and the heat dissipation efficiency thereof is decreased. According to the outdoor unit 1-1 of the first embodiment, the electric components 17 are in contact with the heat dissipator 18-1 whose cooling efficiency is improved, and thus the decrease in the heat dissipation efficiency of the electric components 17 itself can be compensated for. As a result, the downsizing can be achieved while reducing heat generation of the reactor and the semiconductor element provided as some of the electric components 17, for example.
Compared to a case where the plurality of electric components 17 is arranged in the Z axis direction, when the plurality of electric components 17 is arranged in the Y axis direction as described above, the heat generated by the plurality of electric components 17 is easily distributed to the plurality of fins 21 so that the plurality of electric components 17 can be effectively cooled.
Moreover, the plurality of electric components 17 is arranged in the Y axis direction so that, as compared to the case where the plurality of electric components 17 is arranged in the Z axis direction, the heat generated by the first electric component 17a is less easily transferred to the second electric component 17b that has a lower allowable temperature than the first electric component 17a even when the first electric component 17a has the highest amount of heat generated, and that it is possible to prevent the second electric component 17b from getting hot and failing.
Moreover, when the first electric component 17a, the second electric component 17b, and the third electric component 17c are arranged in the order of the first electric component 17a, the second electric component 17b, and the third electric component 17c from the windward side to the leeward side, the heat generated by the first electric component 17a and the second electric component 17b causes the temperature of certain ones of the plurality of fins 21 to be higher than the temperature of the rest of the fins 21. Therefore, the heat generated by the third electric component 17c on the leeward side is less easily absorbed by the fins. On the other hand, when the first electric component 17a, the second electric component 17b, and the third electric component 17c are arranged in the Y axis direction as illustrated in
When the first electric component 17a is a semiconductor element formed by a wide bandgap semiconductor, the wide bandgap semiconductor has higher heat resistance performance and higher switching speed than a silicon semiconductor. Therefore, the reactor, the motor, and the like can be downsized by operating the first electric component 17a at a high frequency. However, the heat generated by the wide bandgap semiconductor may have a higher value than the heat generated by the silicon semiconductor depending on the frequency, so that the first electric component 17a needs to be sufficiently cooled.
Also, the reactor being downsized can be provided on the control substrate 16. When the reactor is thus provided on the control substrate 16, it is necessary to reduce the influence of the heat generated by the reactor on a component existing around the reactor, and to prevent solder used for connecting reactor terminals to the control substrate 16 from melting due to the heat generated by the reactor. Therefore, when the reactor is provided on the control substrate 16, it is necessary to sufficiently cool the reactor and to prevent or reduce an increase in the temperature of the reactor as compared to a case where the reactor is installed in a place other than the control substrate 16.
According to the heat dissipator 180 illustrated in
Also, in a case where an electrolytic capacitor is provided as a component not in contact with the heat dissipator 180, as described above, the life of the electrolytic capacitor is roughly doubled when the ambient temperature drops by 10° C. Even when such a component easily affected by the ambient temperature is used, the heat dissipator 180 illustrated in
An end of the flat surface portion 20a on an opposite side of the inclined portion 20b forms a leeward end surface 20d. The position of the leeward end surface 20d in the Z axis direction is the same as the position of the leeward end surfaces 21d of the fins 21 in the Z axis direction.
The inclined portion 20b functions as a first guide piece that guides the airflow AF generated in the housing 2 to the inlet 24 of the heat dissipator 18-2. The inclined portion 20b is a surface that is inclined at a certain angle θ toward the bottom panel 6 with respect to the Z axis direction. The certain angle θ is an arbitrary angle from 1° to 89°, for example. A tip of the inclined portion 20b forms a windward end surface 20c. The windward end surface 20c is provided on the windward side relative to the windward end surfaces 21c of the plurality of fins 21.
The flat surface portion 20a functions as a second guide piece that guides the air introduced into the air passage 23 surrounded by the base and the fins through the inlet 24 to the outlet 25.
In the heat dissipator 18-2, the air passage 23 is formed by the space surrounded by the base 19, the fins 21 adjacent to each other, and the flat surface portion 20a.
According to the heat dissipator 18-2 illustrated in
Moreover, according to the heat dissipator 18-2A, a part of the end surface 211 of the fins 21 communicates with the region R having the pressure lower than the pressure of the closed space F, so that the velocity of flow of the air flowing from the inlet 24 to the outlet 25 of the heat dissipator 18-2A can be further increased, and that the cooling efficiency of the electric components 17 in contact with the heat dissipator 18-2A is further improved.
Note that any of the deflector plates 20 and 20A illustrated in
Furthermore, in the first embodiment, the outdoor unit 1-1 when viewed from the front is provided with the blower chamber 11 on the left side and the compressor chamber 12 on the right side, but the outdoor unit 1-1 may be provided with the compressor chamber 12 on the left side and the blower chamber 11 on the right side. The similar applies to the outdoor unit 1-2 according to the second embodiment.
The configuration illustrated in the above embodiment merely illustrates an example of the content of the present invention, and can thus be combined with another known technique or partially omitted and/or modified without departing from the scope of the present invention.
Filing Document | Filing Date | Country | Kind |
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PCT/JP2018/032001 | 8/29/2018 | WO |
Publishing Document | Publishing Date | Country | Kind |
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WO2020/044473 | 3/5/2020 | WO | A |
Number | Name | Date | Kind |
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20210123612 | Shimomugi et al. | Apr 2021 | A1 |
Number | Date | Country |
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202769837 | Mar 2013 | CN |
105571014 | May 2016 | CN |
111684209 | Sep 2020 | CN |
2003-139352 | May 2003 | JP |
2003139352 | May 2003 | JP |
2009-299907 | Dec 2009 | JP |
2009299907 | Dec 2009 | JP |
2013-137132 | Jul 2013 | JP |
2018-113321 | Jul 2018 | JP |
Entry |
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Office Action dated Jan. 4, 2023 issued in corresponding JP Patent Application No. 2020-539931 (and English translation). |
Office Action dated Jan. 17, 2022 issued in corresponding CN Patent Application No. 201880096811.2 (and English translation). |
International Search Report of the International Searching Authority dated Nov. 20, 2018 for the corresponding international application No. PCT/JP2018/032001 (and English translation). |
Office Action dated Oct. 5, 2021 issued in corresponding JP Application No. 2020-539931 (and English translation). |
Office Action dated Sep. 13, 2021 issued in corresponding CN Application No. 201880096811.2 (and English translation). |
Decision of Refusal dated Apr. 12, 2022 in corresponding JP Patent Application No. 2020-539931 (with English machine translation). |
Chinese decision of refusal with a full English machine translation (Chinese Application No. 201880096811.2, dated Apr. 21, 2022). |
Number | Date | Country | |
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20210156574 A1 | May 2021 | US |