This application is a U.S. national stage application of International Application No. PCT/JP2013/076315 filed on Sep. 27, 2013 and is based on Japanese Patent Application No. 2012-223017 filed on Oct. 5, 2012, the disclosures of which are incorporated by reference.
The present invention relates to an outdoor unit used in a refrigeration cycle device, and the like.
In some existing refrigeration cycle devices, an outdoor unit includes a single air heat exchanger with multiple (e.g., two) vertically aligned blower devices. In such an outdoor unit, at least in a state where the blower devices operate at high fan rotation speeds (referred to as rotation speed below), setting of the rotation speed of the blower device located above can be switched between a lower speed and a higher speed than that of the blower device located below. By thus making the rotation speeds of the two blower devices different from each other, noise generated by rotation of the two blower devices is reduced (see Patent Literature 1, for example).
Patent Literature 1: Japanese Patent No. 4430258 (FIG. 1)
However, when two blower devices are driven so as to operate at different rotation speeds in such an outdoor unit in which two blower devices are vertically aligned as in Patent Document 1, the pressure in the blower room is unevenly distributed, which causes a phenomenon such as a short cycle or a vortex. Consequently, the air flow rates in the air heat exchanger vary, whereby the performance of the heat exchanger may be reduced, or noise may be increased, for example.
Meanwhile, for example, for the convenience of, for example, the arrangement of components in an outdoor unit, individual areas of the entire heat exchanger do not necessarily have the same distance to blower devices. In such a case, even when the blower devices are driven so as to operate at the same rotation speed, the flow rate of the air flowing into an area located far from the blower devices is low, for example. Consequently, the air flow rates in the air heat exchanger vary, whereby the performance of the air heat exchanger may be decreased.
The present invention has been made to solve the above-described problems and aims to provide an outdoor unit and the like that are capable of reducing variations in the air flow rates in an air heat exchanger.
An outdoor unit according to the present invention includes an outdoor air heat exchanger formed of an air heat exchanger, the air heat exchanger including a plurality of aligned fins and a heat transfer tube including a plurality of heat transfer tube segments, the heat exchanger segments intersecting the fins at a plurality of positions and allowing a refrigerant to flow therein, and the air heat exchanger exchanging heat between the refrigerant and air; and a blower device forming a flow of the air flowing through the outdoor air heat exchanger. In the outdoor air heat exchanger, the heat transfer tube intersects the fins at a larger interval in an area of the outdoor air heat exchanger into which air flows at a low air flow rate than an interval in an area of the outdoor air heat exchanger into which air flows at a low air flow rate.
According to the outdoor unit of the present invention, the heat transfer tube intersects the fins at an interval determined on the basis of the flow rate of the air flowing into the outdoor air heat exchanger according to the positional relationship with the blower device. With this configuration, variations in the air flow rates in the outdoor air heat exchanger can be reduced. This enables a refrigeration cycle device to operate efficiently and save energy, for example.
The compressor 101 sucks the refrigerant, compresses the refrigerant so that the refrigerant has a high temperature and a high pressure, and discharges the refrigerant. As the compressor 101 of Embodiment 1, a compressor of a type capable of adjusting the amount of refrigerant to be discharged by controlling the rotation speed with an inverter circuit, for example, may be used. The four-way valve 102 is a valve that switches the flow direction of the refrigerant depending on whether an air-conditioning device, for example, is to perform cooling operation or heating operation. The outdoor air heat exchanger 103 functions as a condenser (radiator) or an evaporator (cooler), for example, and exchanges heat between the refrigerant and air (outdoor air). The outdoor air heat exchanger 103 will be described later.
The expansion valve 104, such as a metering device (flow rate control means), included in the indoor unit 120 decompresses the refrigerant in order to expand the refrigerant. For example, when an electronic expansion valve is used as the expansion valve 104, the opening degree is adjusted according to an instruction from a means such as a control means (not illustrated). The indoor air heat exchanger 105, which serves as a load heat exchanger, exchanges heat between the air (load) targeted for air conditioning, for example, and the refrigerant. In heating operation, the indoor air heat exchanger 105 functions as a condenser (radiator) and heats the air by causing the refrigerant to radiate heat. By contrast, in cooling operation, the indoor air heat exchanger 105 functions as an evaporator (cooler) and cools the air by causing the refrigerant to absorb heat.
The multiple blower fans 202 vertically aligned (in the vertical direction) are provided in the outdoor unit 110 (casing). The blower fans 202 form a flow of air flowing through the outdoor air heat exchanger 103, in such a way as to promote the heat exchange between the air and the refrigerant in the outdoor air heat exchanger 103. Here, the blower fans 202 are provided in an upper part of the outdoor unit 110 (casing). In addition, an empty space in a lower part is used as a lower space 203. In the lower space 203, a control board that controls the refrigeration cycle device, components, such as the compressor 101, that form the refrigeration cycle device, and the like, for example, are provided.
Here, in the outdoor unit 110 of Embodiment 1, the outdoor air heat exchanger 103 (air heat exchanger 201) is placed so that the heat transfer tube segments 301 are vertically aligned. In addition, in the air heat exchanger 201 of Embodiment 1, vertical pitches (intervals) Dp between the intersections of the heat transfer tube segments 301 and the fins 302 are set to increase toward the lower side of the heat transfer tube segments. Meanwhile, the pitches Fp of the fins 302 are the same.
Next, the operation and the like of each of the components of the refrigeration cycle device will be described on the basis of the flow of the refrigerant circulating in the refrigerant circuit. First, a description will be given taking cooling operation as an example. The compressor 101 sucks the refrigerant, compresses the refrigerant so that the refrigerant has a high temperature and a high pressure, and discharges the compressed refrigerant. The discharged refrigerant flows into the outdoor air heat exchanger 103 via the four-way valve 102. The outdoor air heat exchanger 103 exchanges heat between outside air provided by the blower fans 202 and the refrigerant in order to cause the refrigerant to radiate heat and to cool the refrigerant. When appropriate, the refrigerant is condensed and liquefied. The cooled refrigerant flows through the expansion valve 104. The expansion valve 104 decompresses the flowing refrigerant. The decompressed refrigerant flows into the indoor air heat exchanger 105. The indoor air heat exchanger 105 heats the refrigerant by exchanging heat between the refrigerant and indoor air, which is a thermal load (heat exchange target), for example, and evaporates and gasifies the refrigerant. The compressor 101 sucks the evaporated and gasified refrigerant.
Next, a description will be given of heating operation. The compressor 101 sucks the refrigerant, compresses the refrigerant so that the refrigerant has a high temperature and a high pressure, and discharges the compressed refrigerant. The discharged refrigerant flows into the indoor air heat exchanger 105 via the four-way valve 102. The indoor air heat exchanger 105 exchanges heat between the refrigerant and indoor air in order to cause the refrigerant to radiate heat and to cool the refrigerant. The cooled refrigerant flows through the expansion valve 104. The expansion valve 104 decompresses the flowing refrigerant. The decompressed refrigerant flows into the outdoor air heat exchanger 103. The outdoor air heat exchanger 103 exchanges heat between the outside air provided by the blower fans 202 and the refrigerant in order to heat the refrigerant and to evaporate and gasify the refrigerant. The compressor 101 sucks the evaporated and gasified refrigerant via the four-way valve 102.
Next, the operation of the outdoor air heat exchanger 103 will be described. As described above, the flow of the refrigerant is split before the refrigerant flows into the outdoor air heat exchanger 103, and the refrigerant flows into the individual paths of the outdoor air heat exchanger 103. The outdoor air heat exchanger 103 exchanges heat by forced-convention heat transfer between the refrigerant flowing into each path and the air flowing through the outdoor air heat exchanger 103 as a result of rotation of the multiple blower fans 202. Here, all the multiple outdoor air heat exchangers 103 are driven at the same rotation speed.
Each flow rate of the air flowing through the outdoor air heat exchanger 103 is determined according to ventilation resistance when all the other conditions are fixed. For example, in the outdoor air heat excharger 103, the air flow rate is low in an area having a high ventilation resistance while being high in an area having a low ventilation resistance. Here, for example, the multiple blower fans 202 are provided in an upper part of the outdoor unit 110 of Embodiment 1. For this reason, the flow rate of the air flowing into a lower area of the outdoor air heat exchanger 103 is lower than that of the air flowing into an upper area of the outdoor air heat exchanger 103, the upper area being closer than the lower area to the blower fans 202.
[Equation 1]
Air flow rate (m3/s)=air flow rate (m/s)×area (m2) (1)
Here, the uppermost pitch Dp of the heat transfer tube segments 301 in the outdoor unit 110 of Embodiment 1 is the same as that of the conventional heat transfer tube segments 301, although not particularly limited to this. Moreover, the pitches are increased gradually in
As presented in
The outdoor unit of Embodiment 1 described above has a configuration such that, in the outdoor air heat exchanger 103 formed of the single air heat exchanger 201, the pitches Dp of the heat transfer tube segments 301 gradually increase toward the bottom. With regard to an outdoor unit of Embodiment 2, description will be given of a case in which an outdoor air heat exchanger 103 is formed by connecting heat transfer tube segments 301 of multiple air heat exchangers 201 (formed in such a way as to be divided into multiple blocks, from the view of the outdoor air heat exchanger 103).
Specifically, the pitch Dp2 of the air exchanger tube 301 of the air heat exchanger 201 provided at a lower position among the multiple air heat exchangers 201 included in the outdoor air heat exchanger 103 is set so as to be larger than the pitch Dp1 of the air exchanger tube 301 of the air heat exchanger 201 provided at an upper position. Moreover, the pitch Dp3 of the air exchanger tube 301 of the air heat exchanger 201 provided at a lower position is set so as to be larger than the pitch Dp2 of the air exchanger tube 301 of the air heat exchanger 201 provided at an upper position.
With this configuration, a lower one of the air heat exchangers 201 has a lower ventilation resistance. This allows the flow rate of the air flowing out from the lower area of the outdoor air heat exchanger 103 to be higher than that of the air flowing into the lower area. In this way, variations in the air flow rates in the vertical direction in the outdoor unit 110 can be reduced, which results in uniform air flow rates being obtained. Hence, it is possible to maintain a certain COP and to operate the refrigeration cycle device at high efficiency.
Moreover, in
In Embodiment 1 and Embodiment 2 described above, the outdoor air heat exchanger 103 has a configuration such that the pitches Dp of the heat transfer tube segments 301 are set so as to increase toward the bottom. An outdoor unit 110 of Embodiment 3 has a configuration in which the pitches of fins 302 included in an outdoor air heat exchanger 103 (air heat exchangers 201) are different.
Specifically, the pitch Fp2 of the fins 302 of the air heat exchanger 201 provided at a lower position among the multiple air heat exchangers 201 included in the outdoor air heat exchanger 103 is set so as to be larger than the pitch Fp1 of the fins 302 of the air heat exchanger 201 provided at an upper position. Moreover, the pitch Fp3 of the fins 302 of the air heat exchanger 201 provided at a lower position is larger than the pitch Fp2 of the fins 302 of the air heat exchanger 201 provided at an upper position.
With this configuration, a lower one of the air heat exchangers 201 has a lower ventilation resistance. This allows the flow rate of the air flowing out from the lower area of the outdoor air heat exchanger 103 to be higher than that of the air flowing into the lower area. In this way, variations in the air flow rates in the vertical direction in the outdoor unit 110 can be reduced, which results in uniform air flow rates being obtained. Hence, it is possible to maintain a certain COP and to operate the refrigeration cycle device at high efficiency.
Moreover, in the outdoor unit 110 of Embodiment 3, fewer fins 302 are needed in the part of the outdoor air heat exchanger 103 where the pitches Fp of the fins 302 are larger than in general. Hence, it is possible to reduce the number of fins and consequently to reduce the manufacturing cost.
Moreover, in
The present invention is applicable to, for example, the outdoor unit 110 including the outdoor air heat exchanger 103 and the blower fans 202. With the application of the present invention, it is possible to reduce variations in the air flow rates of the entire air heat exchanger and consequently to enhance the efficiency of the refrigeration cycle.
Such a refrigeration cycle device as one described above in Embodiment 1 can be used as a refrigeration cycle device of, for example, an air-conditioning device, a refrigerator, a water heater, or a chiller. Using the outdoor unit according to the present invention enables such a device to operate highly efficiently.
101 compressor 102 four-way valve 103 outdoor air heat exchanger 104 expansion valve 105 indoor air heat exchanger 110 outdoor unit 120 indoor unit 201 air heat exchanger 202 blower fan 203 lower space 301 heat transfer tube 302 fin 303 flat multi-hole tube
Number | Date | Country | Kind |
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2012-223017 | Oct 2012 | JP | national |
Filing Document | Filing Date | Country | Kind |
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PCT/JP2013/076315 | 9/27/2013 | WO | 00 |
Publishing Document | Publishing Date | Country | Kind |
---|---|---|---|
WO2014/054533 | 4/10/2014 | WO | A |
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20080053643 | Takagi | Mar 2008 | A1 |
20140196874 | Miyake | Jul 2014 | A1 |
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46-36309 | Dec 1971 | JP |
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6-18063 | Jan 1994 | JP |
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2008-138939 | Jun 2008 | JP |
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Entry |
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International Search Report of the International Searching Authority mailed Dec. 24, 2013 for the corresponding international application No. PCT/JP2013/076315 (and English translation). |
Office Action mailed Oct. 29, 2013 for corresponding JP Application No. 2012-223017 (and English translation). |
Number | Date | Country | |
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20150226489 A1 | Aug 2015 | US |