JP2015183976A - Refrigeration cycle device - Google Patents

Abstract

PROBLEM TO BE SOLVED: To make a defrosting operation be hardly started during a heating operation and to improve efficiency of the heating operation by operating an ejector in order to solve such the problem that in the conventional refrigeration cycle device having the ejector and a plurality of heat exchangers, the heating operation stops due to switching, at the defrosting operation, to a cycle the same as a refrigeration cycle at the cooling operation.SOLUTION: In a refrigeration cycle device of the present invention, an outdoor heat exchanger comprises three heat exchangers. During low outdoor-temperature when frosting can easily occur, a cooling medium ejected from a diffuser flows in one of the heat exchangers, and a cooling medium sucked into a suction port flows in the other two heat exchangers. One of the two heat exchangers in which the cooling medium to be sucked flows is made to function as a heat radiator, and the other of the two heat exchangers is made to function as an evaporator, and thereby frosting is restrained.

Description

  The present invention provides a role of refrigerant decompression means for decompressing the refrigerant sucked from the suction port, an ejector serving as a refrigerant circulation means by boosting the refrigerant sucked from the suction port, and a plurality connected to the suction port of the ejector and the diffuser The present invention relates to a refrigeration cycle apparatus having a heat exchanger provided with a heat exchanger.

  The role of the refrigerant pressure reducing means for reducing the pressure of the refrigerant sucked from the suction port, the ejector functioning as the refrigerant circulation means by boosting the pressure of the refrigerant sucked from the suction port, and a plurality of heat exchange parts connected to the suction port and the diffuser of the ejector A refrigeration cycle apparatus having a heat exchanger provided with is known from Patent Document 1 and the like. The refrigeration cycle apparatus of Patent Document 1 has two heat exchange units (first heat exchange unit, second heat exchange unit) for the purpose of effectively using all heat exchangers during cooling operation and heating operation. A first heat exchange unit is connected to the suction port of the ejector, and a second heat exchanger is connected to the diffuser of the ejector.

  In the refrigeration cycle apparatus of Patent Document 1, during the cooling operation, the ejector operates by flowing in the refrigerant from both the suction port and the suction port and ejecting the refrigerant from the diffuser. However, the suction port of the ejector is closed during the heating operation, and the refrigerant flows in from the diffuser of the ejector and flows out of the suction port, so that it does not function as an ejector. Further, during the defrosting operation, the ejector suction port is closed, and the refrigerant flows from the ejector suction port and flows out from the diffuser. Therefore, the ejector does not function.

JP 2007-198675 A

  In the refrigeration cycle apparatus according to Patent Document 1, there is a problem that the heating operation is stopped because the refrigeration cycle is switched to the same cycle as the refrigeration cycle during the cooling operation. In order to solve this problem, the refrigeration cycle apparatus of Patent Document 1 changes the usage of the outdoor heat exchanger and the indoor heat exchanger, and the outdoor heat exchanger has two heat exchange parts (first heat exchange part, first heat exchange part, In order to make it difficult to switch to the defrosting operation, for example, by making it difficult for the outdoor heat exchanger to be frosted, the first heat exchange portion of the outdoor heat exchanger is used as a radiator. It is conceivable to make the second heat exchange part function as an evaporator.

  However, in this method, the refrigerant sucked into the suction port of the ejector may be radiated and cooled by the second heat exchange unit functioning as an evaporator, and may be in a two-phase state. Therefore, the ejector cannot be operated normally, and the efficiency during heating operation may not be improved.

  Then, this invention makes it difficult to switch to a defrost operation at the time of heating operation, and it aims at operating the ejector and improving the efficiency of heating operation.

  Therefore, the refrigeration cycle apparatus of the present invention includes a compressor, an indoor heat exchanger, an ejector including a nozzle part, a suction part, and a diffuser part, a first outdoor heat exchange part, a second outdoor heat exchange part, and a third outdoor part. A refrigeration cycle apparatus in which an outdoor heat exchanger having a heat exchanging unit is sequentially connected in an annular manner by a refrigerant pipe, and in the heating operation, the refrigerant that has flowed out from the diffuser portion of the ejector absorbs heat and flows into the compressor A second outdoor heat exchange section of the exchanger, a branch section that branches out a part of the refrigerant that flows out of the indoor heat exchanger and flows into the nozzle section of the ejector, and a first expansion that depressurizes the refrigerant branched in the branch section A valve, a first outdoor heat exchanger of the outdoor heat exchanger that radiates the refrigerant decompressed by the first expansion valve, a second expansion valve that depressurizes the refrigerant radiated by the first outdoor heat exchanger, Refrigerant decompressed by the expansion valve Heated by, including a third outdoor heat exchanger of the outdoor heat exchanger for guiding the suction port of the ejector.

  Further, the first expansion valve reduced the inflowing refrigerant from a high pressure to an intermediate pressure, and the second expansion valve reduced the inflowing refrigerant from an intermediate pressure to a low pressure.

  In addition, a blower fan that sends air to the first outdoor heat exchange unit, the second outdoor heat exchange unit, and the third outdoor heat exchange unit is provided, and the first outdoor heat exchange unit faces the blower fan, and the second outdoor heat exchange unit It arrange | positions in an upwind side rather than an exchange part and a 3rd outdoor heat exchange part.

  According to the refrigeration cycle apparatus according to the present invention, it is difficult to enter the defrosting operation during the heating operation, and the efficiency of the heating operation can be improved by operating the ejector.

It is a figure which shows the refrigeration cycle apparatus at the time of the heating operation which concerns on this invention. It is a figure which shows the refrigerating cycle apparatus at the time of the air_conditionaing | cooling operation which concerns on this invention.

  Hereinafter, embodiments according to the present invention will be described in detail with reference to the drawings.

  1 and 2 are diagrams showing a refrigeration cycle apparatus 100 of the present embodiment according to the present invention. In the present embodiment, the vapor compression refrigeration cycle apparatus using the ejector 140 according to the present invention is described as being applied to an air conditioner using carbon dioxide (CO2) as a refrigerant.

  As shown in FIG. 1, the refrigeration cycle apparatus 100 includes a compressor 110 having a discharge port 110a and a suction port 110b, a four-way valve 120, an indoor heat exchanger 130, a nozzle unit 141, a suction unit 142, and a mixing unit. 143, an ejector 140 including a diffuser unit 144, an outdoor heat exchanger 150 including a first outdoor heat exchange unit 151, a second outdoor heat exchange unit 152, and a third outdoor heat exchange unit 153, a first expansion valve 161, And a second expansion valve 162.

Each of the above components is connected by a refrigerant flow path described below.
The discharge port 110 a of the compressor 110 and the four-way valve 120 are connected by a first refrigerant channel 201. The four-way valve 120 and the indoor heat exchanger 130 are connected by the second refrigerant flow path 202. The indoor heat exchanger 130 and the nozzle portion 141 of the ejector 140 are connected by a third refrigerant channel 203. The diffuser part 144 of the ejector 140 and the second outdoor heat exchange part 152 of the outdoor heat exchanger 150 are connected by the fourth refrigerant flow path 204. The second outdoor heat exchanger 152 of the outdoor heat exchanger 150 and the four-way valve 120 are connected by a fifth refrigerant channel 205. The four-way valve 120 and the suction port 110 b of the compressor 110 are connected by a sixth refrigerant channel 206.

A branch part 170 is provided on the third refrigerant flow path 203, and a part of the refrigerant flowing between the indoor heat exchanger 130 and the nozzle part 141 of the ejector 140 is branched by the branch part 170.
The branch part 170 and the first expansion valve 161 are connected by a seventh refrigerant channel 207. The first expansion valve 161 and the first outdoor heat exchanger 151 of the outdoor heat exchanger 150 are connected by an eighth refrigerant channel 208. The first outdoor heat exchanger 151 and the second expansion valve 162 of the outdoor heat exchanger 150 are connected by a ninth refrigerant channel 209. The second expansion valve 162 and the third outdoor heat exchanger 153 of the outdoor heat exchanger 150 are connected by the tenth refrigerant flow path 210. The third outdoor heat exchange part 153 of the outdoor heat exchanger 150 and the suction part 142 of the ejector 140 are connected by an eleventh refrigerant channel 211. Refrigerant piping is used for each refrigerant channel from the first refrigerant channel to the eleventh refrigerant channel.

Next, each structure of the refrigerating cycle apparatus 100 of this embodiment is demonstrated.
The compressor 110 compresses the refrigerant sucked from the suction port 110b and discharges it from the discharge port 110a as a high-temperature and high-pressure refrigerant.

  The four-way valve 120 switches the direction of the refrigerant flowing in the refrigeration cycle apparatus 100 between the cooling operation and the heating operation. The four-way valve 120 causes the high-temperature and high-pressure refrigerant discharged from the compressor 110 to flow into the second outdoor heat exchanger 152 of the outdoor heat exchanger 150 as shown in FIG. The refrigerant that has flowed out flows into the compressor 110. Further, during the heating operation, as shown in FIG. 1, the high-temperature and high-pressure refrigerant discharged from the compressor 110 is caused to flow into the indoor heat exchanger 130, and the refrigerant flowing out from the second outdoor heat exchanger 152 of the outdoor heat exchanger 150 is allowed to flow. It flows into the compressor 110.

  The indoor heat exchanger 130 is provided in an indoor unit (not shown), and exchanges heat between indoor air and refrigerant, functions as an evaporator during cooling operation, and functions as a radiator during heating operation. To do.

  The outdoor heat exchanger 150 is provided in an outdoor unit (not shown) and exchanges heat between outdoor air and the refrigerant. The outdoor heat exchanger 150 includes a first outdoor heat exchange unit 151, a second outdoor heat exchange unit 152, and a third outdoor heat exchange unit 153. In addition, the outdoor heat exchanger 150 is provided with a blower fan 180 that blows air to the outdoor heat exchanger 150. The first outdoor heat exchange unit 151, the second outdoor heat exchange unit 152, and the third outdoor heat exchange unit 153 are opposed to the blower fan 180, and the first outdoor heat exchange unit 151 is connected to the second outdoor heat exchange unit 152. It arrange | positions from the 3rd outdoor heat exchange part 153 to the windward side. In the heating operation at the low outdoor temperature, the second outdoor heat exchange unit 152 is hotter than the third outdoor heat exchange unit 153, and therefore the second outdoor heat exchange unit 152 is located on the windward side of the third outdoor heat exchange unit 153. Placed in. In addition, this invention is not limited to this, The 2nd outdoor heat exchange part 152 may be arrange | positioned under the 3rd outdoor heat exchange part 153. FIG.

  The ejector 140 includes a nozzle part 141, an inlet 141a of the nozzle part 141, an outlet part 141b of the nozzle part 141, a suction part 142, a mixing part 143, a diffuser part 144, and an outlet 144a of the diffuser part 144. Is done. In addition, the exit part 141b of the nozzle part 141 has a structure in which the opening degree can be adjusted, and the nozzle part 141 can be fully closed by setting the opening degree of the outlet part 141b to zero.

  During the heating operation, the ejector 140 functions as an ejector, and the gas refrigerant flowing out from the indoor heat exchanger 130 is sucked from the inlet 141a of the nozzle portion 141 via the third refrigerant flow path 203. In addition, the refrigerant that has flowed out from the third outdoor heat exchange unit 153 of the outdoor heat exchanger 150 is sucked from the suction unit 142 via the eleventh refrigerant channel 211. The refrigerant sucked from the nozzle part 141 and the refrigerant sucked from the suction part 142 are mixed by the mixing part 143. The mixed refrigerant converts the velocity energy of the refrigerant into pressure energy in the diffuser unit 144, and the pressure of the refrigerant is increased.

  During the cooling operation, the outlet 141b of the ejector nozzle portion 141 is closed, so that the ejector 140 functions as a refrigerant pipe. The gas refrigerant that has flowed out of the second outdoor heat exchanger 152 of the outdoor heat exchanger 150 is sucked from the outlet 144a of the diffuser section 144 via the fourth refrigerant flow path 204. The refrigerant sucked into the nozzle part 141 flows out from the suction part 142 via the mixing part 143.

Next, operation | movement of the refrigerating-cycle apparatus 100 using the ejector 140 of the said structure is demonstrated.
(Heating operation)
First, the case where the refrigeration cycle apparatus 100 is performing a normal heating operation will be described with reference to FIG. In this case, the first expansion valve 161 is throttled to a predetermined opening so that the refrigerant is depressurized from high pressure to low pressure, and the second expansion valve 162 is fully opened. The dotted arrows indicate the flow of the refrigerant.

  When the compressor 110 is activated, the compressor 110 sucks the gas-phase refrigerant from the suction port 110b, compresses it, and discharges it from the discharge port 110a. The refrigerant discharged from the compressor 110 flows into the indoor heat exchanger 130 functioning as a radiator via the first refrigerant channel 201, the four-way valve 120, and the second refrigerant channel 202. The refrigerant that has flowed into the indoor heat exchanger 130 exchanges heat with the indoor air and dissipates heat. The radiated refrigerant passes through the third refrigerant flow path 203 at the branching section 170 and flows into the inlet 141a of the nozzle section 141 of the ejector 140, the first outdoor heat exchange section 151 of the outdoor heat exchanger 150, The refrigerant is branched to the suction refrigerant sucked from the suction part 142 via the third outdoor heat exchange part 153.

  The suction refrigerant is branched from the branching section 170 and then reduced in pressure from the high pressure to the low pressure by the first expansion valve 161 adjusted to a predetermined opening degree via the seventh refrigerant flow path 207. The decompressed refrigerant flows into the first outdoor heat exchanger 151 functioning as an evaporator of the outdoor heat exchanger 150 via the eighth refrigerant flow path 208, and absorbs heat by exchanging heat with outdoor air. The refrigerant that has absorbed heat passes through the second expansion valve 162 via the ninth refrigerant flow path 209 and then passes through the tenth refrigerant flow path 210 to function as an evaporator of the outdoor heat exchanger 150. It flows into the section 153 and again exchanges heat with outdoor air to absorb heat and evaporate. The evaporated refrigerant is sucked from the suction part 142 of the ejector 140 via the eleventh refrigerant flow path 211.

  On the other hand, the inflowing refrigerant that flows into the inlet 141a of the nozzle portion 141 sucks the refrigerant that has been decompressed and expanded by the nozzle portion 141 and evaporated from the suction portion 142 in the third outdoor heat exchange portion 153 of the outdoor heat exchanger 150.

  Then, while mixing the suction refrigerant sucked from the suction part 142 and the inflow refrigerant blown from the outlet 141b of the nozzle part 141 in the mixing part 143, the dynamic pressure is converted into static pressure in the diffuser part 144, and the outdoor heat The heat is discharged to the second outdoor heat exchange unit 152 of the exchanger 150. At this time, in the mixing unit 143, since the inflowing refrigerant and the suction refrigerant are mixed so that the sum of the momentum of the inflowing refrigerant and the momentum of the suctioning refrigerant is preserved, the refrigerant pressure also increases in the mixing unit 143. . By gradually expanding the passage cross-sectional area in the diffuser part 144, the speed energy of the refrigerant is converted into pressure energy, so that the pressure of the refrigerant is further increased.

  The refrigerant that has flowed into the second outdoor heat exchanger 152 of the outdoor heat exchanger 150 exchanges heat with outdoor air and absorbs heat. The refrigerant that has absorbed heat is sucked from the suction port 110b of the compressor 110 via the fifth refrigerant channel 205, the four-way valve 120, and the sixth refrigerant channel 206. The refrigerant circulates through each configuration described above.

(Heating operation at low outside temperature)
Next, a condition where the outdoor heat exchanger 150 is likely to be frosted, for example, when the refrigeration cycle apparatus 100 is in a heating operation when the outside air temperature detected by an outside air temperature sensor (not shown) falls below a predetermined temperature. A description will be given based on FIG. In this case, the first expansion valve 161 is throttled to a predetermined opening degree so that the refrigerant is reduced from high pressure to intermediate pressure, and the second expansion valve 162 is throttled to a predetermined opening degree to reduce pressure from the intermediate pressure to low pressure. . The dotted arrows indicate the flow of the refrigerant.

  When the compressor 110 is activated, the compressor 110 sucks the gas-phase refrigerant from the suction port 110b, compresses it, and discharges it from the discharge port 110a. The refrigerant discharged from the compressor 110 flows into the indoor heat exchanger 130 functioning as a radiator via the first refrigerant channel 201, the four-way valve 120, and the second refrigerant channel 202. The refrigerant that has flowed into the indoor heat exchanger 130 exchanges heat with the indoor air and dissipates heat. The radiated refrigerant passes through the third refrigerant flow path 203 at the branching section 170 and flows into the inlet 141a of the nozzle section 141 of the ejector 140, the first outdoor heat exchange section 151 of the outdoor heat exchanger 150, The refrigerant is branched to the suction refrigerant sucked from the suction part 142 via the third outdoor heat exchange part 153.

  The suction refrigerant is branched from the branching section 170 and then reduced from a high pressure to an intermediate pressure by the first expansion valve 161 adjusted to a predetermined opening degree via the seventh refrigerant flow path 207. The decompressed refrigerant flows into the first outdoor heat exchanger 151 of the outdoor heat exchanger 150 functioning as a radiator via the eighth refrigerant channel 208, and radiates heat by exchanging heat with the outdoor air. The radiated refrigerant is decompressed from the intermediate pressure to the low pressure by the second expansion valve 162 adjusted to a predetermined opening degree via the ninth refrigerant flow path 209. The decompressed refrigerant flows into the third outdoor heat exchanger 153 that functions as the evaporator of the outdoor heat exchanger 150 via the tenth refrigerant flow path 210, and exchanges heat with outdoor air to absorb heat and evaporate. The evaporated refrigerant is sucked from the suction part 142 of the ejector 140 via the eleventh refrigerant flow path 211. The heat radiated by the first outdoor heat exchanging portion 151 heats the second outdoor heat exchanging portion 152 and the third outdoor heat exchanging portion 153, and frost is hardly formed.

  On the other hand, the inflowing refrigerant that flows into the inlet 141a of the nozzle portion 141 sucks the refrigerant that has been decompressed and expanded by the nozzle portion 141 and evaporated from the suction portion 142 in the third outdoor heat exchange portion 153 of the outdoor heat exchanger 150.

  Then, while mixing the suction refrigerant sucked from the suction part 142 and the inflow refrigerant blown from the outlet 141b of the nozzle part 141 in the mixing part 143, the dynamic pressure is converted into static pressure in the diffuser part 144, and the outdoor heat The heat is discharged to the second outdoor heat exchange unit 152 of the exchanger 150. At this time, in the mixing unit 143, since the inflowing refrigerant and the suction refrigerant are mixed so that the sum of the momentum of the inflowing refrigerant and the momentum of the suctioning refrigerant is preserved, the refrigerant pressure also increases in the mixing unit 143. . By gradually expanding the passage cross-sectional area in the diffuser part 144, the speed energy of the refrigerant is converted into pressure energy, so that the pressure of the refrigerant is further increased.

  The refrigerant flowing into the second outdoor heat exchanger 152 of the outdoor heat exchanger 150 exchanges heat with the outdoor air and absorbs heat to evaporate. The evaporated refrigerant is sucked from the suction port 110b of the compressor 110 via the fifth refrigerant channel 205, the four-way valve 120, and the sixth refrigerant channel 206. The refrigerant circulates through each configuration described above.

(Cooling operation)
Next, the case where the refrigeration cycle apparatus 100 is performing a cooling operation will be described with reference to FIG. In this case, the outlet 141b of the nozzle portion 141 of the ejector 140 is closed, the first expansion valve 161 is throttled to a predetermined opening degree so that the refrigerant is reduced from high pressure to low pressure, and the second expansion valve 162 is fully opened. . The dotted arrows indicate the flow of the refrigerant.

  When the compressor 110 is activated, the compressor 110 sucks the gas-phase refrigerant from the suction port 110b, compresses it, and discharges it from the discharge port 110a. The refrigerant discharged from the compressor 110 flows into the second outdoor heat exchanger 152 functioning as a radiator of the outdoor heat exchanger 150 via the first refrigerant channel 201, the four-way valve 120, and the fifth refrigerant channel 205. To do. The refrigerant flowing into the second outdoor heat exchange unit 152 exchanges heat with the outdoor air and dissipates heat. The radiated refrigerant flows in from the outlet 144a of the diffuser section 144 of the ejector 140 functioning as a refrigerant pipe via the fourth refrigerant flow path 204, and flows out of the suction section 142 through the diffuser section 144 and the mixing section 143. .

  The refrigerant that has flowed out of the suction part 142 flows into the third outdoor heat exchange part 153 that functions as a radiator of the outdoor heat exchanger 150 via the eleventh refrigerant flow path 211. The refrigerant that has flowed into the third outdoor heat exchange unit 153 exchanges heat with outdoor air to dissipate heat. The radiated refrigerant passes through the second expansion valve 162 via the tenth refrigerant flow path 210 and then flows into the first outdoor heat exchange unit 151 functioning as a heat radiator via the ninth refrigerant flow path 209. The refrigerant flowing into the first outdoor heat exchange unit 151 exchanges heat with the outdoor air and dissipates heat. The radiated refrigerant is depressurized from high pressure to low pressure by the first expansion valve 161 adjusted to a predetermined opening degree via the eighth refrigerant flow path 208. The decompressed refrigerant flows into the third refrigerant flow path 203 at the branching portion 170 via the seventh refrigerant flow path 207 and flows into the indoor heat exchanger 130 functioning as an evaporator.

  The refrigerant flowing into the indoor heat exchanger 130 exchanges heat with room air and absorbs heat to evaporate. The evaporated refrigerant is sucked from the suction port 110b of the compressor 110 via the second refrigerant channel 202, the four-way valve 120, and the sixth refrigerant channel 206. The refrigerant circulates through each configuration described above.

  As described above, the refrigeration cycle apparatus 100 according to the present invention causes the first outdoor heat exchanger 151, which is a part of the outdoor heat exchanger 150, to function as a radiator when the outdoor heat exchanger 150 is likely to be frozen. Thus, it is possible to suppress frost formation of other heat exchange units (second outdoor heat exchange unit 152 and third outdoor heat exchange unit 153) functioning as an evaporator. Thereby, it becomes difficult to switch to the defrosting operation.

DESCRIPTION OF SYMBOLS 100 Refrigeration cycle apparatus 110 Compressor 120 Four-way valve 130 Indoor heat exchanger 140 Ejector 150 Outdoor heat exchanger 161 1st expansion valve 162 2nd expansion valve 170 Branch part 180 Blower fan

Claims (3)

An outdoor heat exchanger having a compressor, an indoor heat exchanger, an ejector including a nozzle part, a suction part, and a diffuser part, a first outdoor heat exchange part, a second outdoor heat exchange part, and a third outdoor heat exchange part; A refrigeration cycle apparatus connected in an annular shape by a refrigerant pipe,
During heating operation,
The second outdoor heat exchange part of the outdoor heat exchanger that absorbs heat from the diffuser part of the ejector and causes the refrigerant to flow into the compressor;
A branching part that branches out a part of the refrigerant that flows out of the indoor heat exchanger and flows into the nozzle part of the ejector;
A first expansion valve for depressurizing the refrigerant branched at the branch portion;
The first outdoor heat exchange part of the outdoor heat exchanger for radiating the refrigerant decompressed by the first expansion valve;
A second expansion valve that depressurizes the refrigerant radiated by the first outdoor heat exchange unit;
A refrigeration cycle apparatus comprising the third outdoor heat exchanger of the outdoor heat exchanger that absorbs heat of the refrigerant decompressed by the second expansion valve and guides the refrigerant to the suction port of the ejector. The refrigeration cycle apparatus according to claim 1,
The first expansion valve depressurizes the flowing refrigerant from a high pressure to an intermediate pressure,
The second expansion valve is a refrigeration cycle apparatus characterized in that the refrigerant flowing in is reduced from an intermediate pressure to a low pressure. The refrigeration cycle apparatus according to claim 1 or 2,
A blower fan is provided to send air to the first outdoor heat exchange unit, the second outdoor heat exchange unit, and the third outdoor heat exchange unit;
The refrigeration cycle apparatus, wherein the first outdoor heat exchange unit is disposed on the windward side of the second outdoor heat exchange unit and the third outdoor heat exchange unit, facing the blower fan.

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