Patent Application
20180331436
The present invention relates to a refrigeration cycle apparatus using a working fluid containing 1,1,2-trifluoroethylene.
In a refrigeration cycle apparatus such as an air-conditioner or a refrigerator, a hydrofluorocarbon (HFC) based refrigerant has been widely used as a working refrigerant. However, HFCs have a high global warming potential (GWP). Thus, it is pointed out that HFCs may cause global warming. It is therefore imperative to develop a working fluid for refrigeration cycles, which has less influence on the ozone layer and has a low GWP. A working fluid containing a hydrofluoroolefin (HFO) having a carbon-carbon double bond which is likely to be decomposed by OH radicals in the air has been studied as a working fluid for refrigeration cycles having less influence on the ozone layer and having less influence on global warming. Patent Document 1 discloses a refrigeration cycle apparatus using a working fluid containing 1,1,2-trifluoroethylene (HFO-1123).
Patent Document 1: JP-A-2015-145452
When a certain level of ignition energy is applied to HFO-1123 in a high-temperature and high-pressure state, a chain of chemical reactions with heat generation may occur. Such a chemical reaction is called disproportionation reaction (self-decomposition reaction). The disproportionation reaction is a chemical reaction in which two or more molecules belonging to the same kind react with each other to generate two or more different kinds of products. When such a disproportionation reaction occurs within a refrigeration cycle apparatus, sudden temperature rise and pressure rise occur to lose the reliability of the refrigeration cycle apparatus.
Within the refrigeration cycle apparatus, places where it is highly likely to apply a certain level of ignition energy to the working fluid under high temperature and high pressure are mainly inside a compressor. When ignition energy is generated inside the compressor due to some event such as occurrence of discharge (spark) in a driving unit, the ignition energy is applied to the working fluid so that disproportionation reactions of HFO-1123 may occur.
The present invention has been developed in consideration of the aforementioned situation. An object of the present invention is to provide a refrigeration cycle apparatus capable of effectively avoiding occurrence of disproportionation reactions of HFO-1123 when a working fluid containing the HFO-1123 is used.
The refrigeration cycle apparatus in the first aspect of the present invention is a refrigeration cycle apparatus comprising a compressor to compress a working fluid containing 1,1,2-trifluoroethylene to perform a refrigeration cycle,
wherein the compressor includes:
a compression unit which compresses the working fluid;
a driving unit which drives the compression unit;
a power supply terminal which supplies electric power from an outside of the compressor to an inside of the compressor; and
a plurality of lead wires which electrically connect the driving unit to the power supply terminal, and
each of the plurality of lead wires is covered with an insulating material having heat resistance of 300° C. or more at least in a part where the lead wires are bundled one another.
In the refrigeration cycle apparatus in the second aspect of the present invention, the plurality of lead wires are connected to the power supply terminal through a connector, and the connector is formed of an insulating material having heat resistance of 300° C. or more.
In the refrigeration cycle apparatus in the third aspect of the present invention, the plurality of lead wires are inserted into the connector in directions of being separated from one another at angles, respectively.
The refrigeration cycle apparatus in the fourth aspect of the present invention is a refrigeration cycle apparatus comprising a compressor to compress a working fluid containing 1,1,2-trifluoroethylene to perform a refrigeration cycle,
wherein the compressor includes:
a compression unit which compresses the working fluid;
a driving unit which drives the compression unit;
a power supply terminal which supplies electric power from an outside of the compressor to an inside of the compressor;
a plurality of lead wires which electrically connect the driving unit to the power supply terminal; and
an insulating material which has heat resistance of 300° C. or more and includes a plurality of through holes disposed at distances from one another, and
each of the plurality of lead wires is disposed to allow a part of the lead wire to pass through each of the plurality of through holes of the insulating material.
In the refrigeration cycle apparatus in the fifth aspect of the present invention, the lead wires are connected to the power supply terminal through a connector, and the connector is formed of an insulating material having heat resistance of 300° C. or more.
In the refrigeration cycle apparatus in the sixth aspect of the present invention, the plurality of lead wires are inserted into the connector in directions of being separated from one another at angles, respectively.
The refrigeration cycle apparatus in the seventh aspect of the present invention is a refrigeration cycle apparatus comprising a compressor to compress a working fluid containing 1,1,2-trifluoroethylene to perform a refrigeration cycle,
wherein the compressor includes:
a compression unit which compresses the working fluid;
a driving unit which drives the compression unit;
a power supply terminal which supplies electric power from an outside of the compressor to an inside of the compressor; and
a plurality of lead wires which electrically connect the driving unit to the power supply terminal, and
the lead wires are connected to the power supply terminal through a connector, and
the connector is formed of an insulating material having heat resistance of 300° C. or more.
In the refrigeration cycle apparatus in the eighth aspect of the present invention, the plurality of lead wires are inserted into the connector in directions of being separated from one another at angles, respectively.
The refrigeration cycle apparatus in the ninth aspect of the present invention is a refrigeration cycle apparatus comprising a compressor to compress a working fluid containing 1,1,2-trifluoroethylene to perform a refrigeration cycle,
wherein the compressor includes:
a compression unit which compresses the working fluid;
a driving unit which drives the compression unit;
a power supply terminal which supplies electric power from an outside of the compressor to an inside of the compressor; and
a plurality of lead wires which electrically connect the driving unit to the power supply terminal, and
the driving unit and the power supply terminal are connected through the plurality of covered lead wires,
the lead wires are connected to the power supply terminal through a connector, and
the plurality of lead wires are inserted into the connector in directions of being separated from one another at angles, respectively.
In a refrigeration cycle apparatus of the present invention, it is possible to effectively avoid occurrence of disproportionation reactions of HFO-1123 in spite of an abnormally high temperature or high pressure condition inside a refrigeration cycle when a working fluid containing the HFO-1123 is used.
Embodiment 1 of the present invention is described below with reference to the drawings.
First, description is made about a working fluid for use in a refrigeration cycle apparatus in the present invention.
A working fluid used in the present invention contains 1,1,2-trifluoroethylene (HFO-1123).
First, description is made about the working fluid for use in the refrigeration cycle apparatus in the present invention.
The properties of HFO-1123 as working fluid are shown in Table 1 particularly by relative comparison with R410A (a pseudoazeotropic mixture refrigerant of HFC-32 and HFC-125 in a mass ratio of 1:1). Cycle performance is evaluated by a coefficient of performance and refrigeration capacity obtained by the later-described methods. The coefficient of performance and the refrigeration capacity of HFO-1123 are expressed by relative values (hereinafter referred to as relative coefficient of performance and relative refrigeration capacity) based on those of R410A as reference (1.000). The global warming potential (GWP) is a 100-years value shown in Intergovernmental Panel on Climate Change (IPCC), Fourth assessment report (2007), and measured in accordance with the method of the same report. In the present specification, GWP unit the value unless otherwise specified. When the working fluid is formed of a mixture, the temperature gradient is a significant factor for evaluating the working fluid, as is described later. It is preferable that the value of the temperature gradient is smaller.
The working fluid used in the present invention preferably contains HFO-1123. In addition to HFO-1123, optional compounds that are usually used as working fluids may be contained as long as they do not impair the effect of the present invention. Examples of such optional compounds (optional components) include HFCs, HFOs (HFCs each having a carbon-carbon double bond) other than HFO-1123, and other components that can be liquefied or vaporized together with HFO-1123. Preferred optional components are HFCs, and HFOs (HFCs each having a carbon-carbon double bond) other than HFO-1123.
Such an optical component is preferably a compound which can set the GWP or the temperature gradient within an acceptable range while enhancing the relative coefficient of performance and the relative refrigeration capacity when it is, for example, used in a heat cycle together with HFO-1123. When the working fluid contains such a compound together with HFO-1123, better cycle performance can be obtained while keeping the GWP low, and the influence of the temperature gradient can be reduced.
When the working fluid contains, for example, HFO-1123 and an optical component, the working fluid has a significant temperature gradient as long as HFO-1123 and the optional component do not form an azeotropic composition. The temperature gradient of the working fluid depends on the kind of the optional component and the mixture ratio between HFO-1123 and the optional component.
Usually, when a mixture is used as the working fluid, an azeotropic mixture or a pseudoazeotropic mixture such as R410A is preferably used. A non-azeotropic composition has a problem that a change in composition occurs when the composition is charged into a refrigerator/air-conditioner from a pressure vessel. Further, when a refrigerant leaks from the refrigerator/air-conditioner, there is an extremely great possibility that the composition of the refrigerant within the refrigerator/air-conditioner may change so that the composition of the refrigerant cannot be recovered to its initial state easily. On the other hand, the problem can be avoided by using an azeotropic or pseudoazeotropic mixture as the working fluid.
The “temperature gradient” is generally used as an index to evaluate availability of a mixture in the working fluid. The temperature gradient is defined as such a property that the initiation temperature and the completion temperature of evaporation in a heat exchanger such as an evaporator or of condensation in a heat exchanger such as a condenser differ from each other. The temperature gradient is 0 in an azeotropic mixture, and the temperature gradient is very close to 0 in a pseudoazeotropic mixture, for example, the temperature gradient of R410A is 0.2.
When the temperature gradient is large, there is a problem that the inlet temperature, for example, in the evaporator decreases so that frosting is more likely to occur. Further, generally in a heat cycle system, a working fluid flowing in a heat exchanger and a heat source fluid such as water or air are made to flow as counter-current flows against each other in order to improve the heat exchange efficiency. Since the temperature difference of the heat source fluid is small in a stable operation state, it is difficult to obtain a heat cycle system with a good energy efficiency when a non-azeotropic mixture fluid with a large temperature gradient is used. Accordingly, when a mixture is used as the working fluid, it is desired that the working fluid has an appropriate temperature gradient.
As the HFC as the optional component, it is preferable to select an HFC from the aforementioned viewpoint. Here, an HFC is known to have a high GWP as compared with HFO-1123. Accordingly, as the HFC used in combination with HFO-1123, it is preferable to select an HFC appropriately in order not only to improve cycle performance as the working fluid and set the temperature gradient within a proper range but also to adjust particularly the GWP within an acceptable range.
As an HFC which has less influence on the ozone layer and which has less influence on global warming, an HFC having 1 to 5 carbon atoms is specifically preferred. The HFC may be linear, branched or cyclic.
Examples of the HFC include HFC-32, difluoroethane, trifluoroethane, tetrafluoroethane, HFC-125, pentafluoropropane, hexafluoropropane, heptafluoropropane, pentafluorobutane, heptafluorocyclopentane and the like.
Among them, in view of less influence on the ozone layer and excellent refrigeration cycle performance, preferable examples of the HFC include HFC-32, 1,1-difluoroethane (HFC-152a), 1,1,1-trifluoroethane (HFC-143a), 1,1,2,2-tetrafluoroethane (HFC-134), 1,1,1,2-tetrafluoroethane (HFC-134a) and HFC-125, and more preferable examples thereof include HFC-32, HFC-152a, HFC-134a and HFC-125.
One kind of HFC may be used alone or two or more kinds of HFCs may be used in combination.
The content of the HFC in the working fluid (100 mass %) may be desirably selected depending on required properties of the working fluid. When the working fluid is, for example, made of HFO-1123 and HFC-32, the coefficient of performance and the refrigeration capacity can be improved when the content of HFC-32 falls within the range of from 1 to 99 mass %. When the working fluid is made of HFO-1123 and HFC-134a, the coefficient of performance can be improved when the content of HFC-134a falls within the range of from 1 to 99 mass %.
With respect to GWP of the aforementioned preferred HFC, GWP of HFC-32 is 675, GWP of HFC-134a is 1,430, and GWP of HFC-125 is 3,500. In order to reduce the GWP of the obtainable working fluid, HFC-32 is the most preferable HFC as the optional component.
HFO-1123 and HFC-32 can form a pseudoazeotropic mixture close to an azeotropic mixture when the mass ratio between the both is from 99:1 to 1:99. The mixture of the both has a temperature gradient close to 0 substantially without selecting a composition range thereof. Also with respect to this point, HFC-32 is advantageous as an HFC to be combined with HFO-1123.
When HFC-32 is used together with HFO-1123 in the working fluid used in the present invention, specifically the content of HFC-32 based on 100 mass % of the working fluid is preferably 20 mass % or more, more preferably from 20 to 80 mass %, and further preferably from 40 to 60 mass %.
When the working fluid used in the present invention, for example, contains HFO-1123, an HFO other than HFO-1123 is preferably HFO-1234yf (GWP=4), HFO-1234ze(E) or HFO-1234ze(Z) (GWP=6 in both the (E)-isomer and the (Z)-isomer), and more preferably HFO-1234yf or HFO-1234ze(E) because they are high in critical temperature and excellent in durability and coefficient of performance. One kind of HFOs other than HFO-1123 may be used alone, or two or more kinds of them may be used in combination. The content of the HFO other than UFO-1123 in the working fluid (100 mass %) may be desirably selected depending on required properties of the working fluid. When the working fluid is, for example, made of HFO-1123 and HFO-1234yf or HFO-1234ze, the coefficient of performance can be improved when the content of HFO-1234yf or HFO-1234ze falls within the range of from 1 to 99 mass %.
When the working fluid used in the present invention contains HFO-1123 and HFO-1234yf, a preferred composition range is shown below as a composition range (S).
In the respective formulae showing the composition range (S), the abbreviation of each compound designates the proportion (mass %) of the compound to the total amount of HFO-1123, HFO-1234yf and other components (HFC-32 and the like).
HFO-1123+HFO-1234yf≥70 mass %
95 mass %≥HFO-1123/(HFO-1123+HFO-1234yf)≥35 mass %
The working fluid in the composition range (S) is extremely low in GWP and small in temperature gradient. In addition, refrigeration cycle performance high enough to replace the R410A in the background art can be exhibited also from the viewpoint of the coefficient of performance, the refrigeration capacity and the critical temperature.
In the working fluid in the composition range (S), the proportion of HFO-1123 to the total amount of HFO-1123 and HFO-1234yf is more preferably from 40 to 95 mass %, further more preferably from 50 to 90 mass %, particularly preferably from 50 to 85 mass %, and most preferably from 60 to 85 mass %.
In addition, the total content of HFO-1123 and HFO-1234yf in 100 mass % of the working fluid is more preferably from 80 to 100 mass %, further more preferably from 90 to 100 mass %, and particularly preferably from 95 to 100 mass %.
In addition, it is preferable that the working fluid used in the present invention contains HFO-1123, HFC-32 and HFO-1234yf. A preferred composition range (P) in a case where the working fluid contains HFO-1123, HFO-1234yf and HFC-32 is shown below.
In the respective formulae showing the composition range (P), the abbreviation of each compound designates the proportion (mass %) of the compound to the total amount of HFO-1123, HFO-1234yf and HFC-32. The same thing can be also applied to the composition range (R), the composition range (L) and the composition range (M). In addition, in the following composition range, it is preferable that the total amount of HFO-1123, HFO-1234yf and HFC-32 described specifically is more than 90 mass % and 100 mass % or less based on the entire amount of the working fluid for heat cycle.
70 mass≤% HFO-1123+HFO-1234yf
30 mass %≤HFO-1123≤80 mass %
0 mass %<HFO-1234yf≤40 mass %
0 mass %<HFC-32≤30 mass %
HFO-1123/HFO-1234yf≤95/5 mass %
The working fluid having the aforementioned composition is a working fluid having respective properties of HFO-1123, HFO-1234yf and HFC-32 in a balanced manner, and having less defects of the respective components. That is, the working fluid is a working fluid which has an extremely low GWP, and has a small temperature gradient and a certain performance and efficiency when used for heat cycle, and thus, favorable cycle performance is obtained by the working fluid. Here, it is preferable that the total amount of HFO-1123 and HFO-1234yf is 70 mass % or more based on the total amount of HFO-1123, HFO-1234yf and HFC-32.
A more preferred composition as the working fluid used in the present invention may be a composition containing HFO-1123 in an amount of from 30 to 70 mass %, HFO-1234yf in an amount of from 4 to 40 mass %, and HFC-32 in an amount of from 0 to 30 mass %, based on the total amount of HFO-1123, HFO-1234yf and HFC-32 and having a content of HFO-1123 in an amount of 70 mol % or less based on the entire amount of the working fluid. The working fluid within the aforementioned range is a working fluid in which self-decomposition reaction of HFO-1123 is inhibited to enhance the durability in addition to the aforementioned effect enhanced. From the viewpoint of the relative coefficient of performance, the content of HFC-32 is preferably 5 mass % or more, and more preferably 8 mass % or more.
Other preferred compositions in the case where the working fluid used in the present invention contains HFO-1123, HFO-1234yf and HFC-32 are shown below. A working fluid in which self-decomposition reaction of HFO-1123 is inhibited to enhance the durability can be obtained as long as the content of HFO-1123 is 70 mol % or less based on the entire amount of the working fluid.
A more preferred composition range (R) is shown below.
10 mass %≤HFO-1123<70 mass %
0 mass %<HFO-1234yf≤50 mass %
30 mass %<HFC-32≤75 mass %
The working fluid having the aforementioned composition is a working fluid having respective properties of HFO-1123, HFO-1234yf and HFC-32 in a balanced manner, and having less defects of the respective components. That is, the working fluid is a working fluid which has a low GWP and ensures durability while having a small temperature gradient and having a high performance and efficiency when used for heat cycle, and thus, favorable cycle performance is obtained by the working fluid.
A preferred range in the working fluid having the composition range (R) is shown below.
20 mass %≤HFO-1123<70 mass %
0 mass %<HFO-1234yf≤40 mass %
30 mass %<HFC-32≤75 mass %
The working fluid having the aforementioned composition is a working fluid having respective properties of HFO-1123, HFO-1234yf and HFC-32 in a balanced manner, and having less defects of the respective components. That is, the working fluid is a working fluid which has a low GWP and ensures durability, while having a smaller temperature gradient and having higher performance and efficiency when used for heat cycle, and thus, favorable cycle performance is obtained by the working fluid.
A more preferable range (L) in the working fluid having the composition range (R) is shown below. A composition range (M) is further more preferable.
10 mass %≤HFO-1123<70 mass %
0 mass %<HFO-1234yf≤50 mass %
30 mass %<HFC-32≤44 mass %
20 mass %≤HFO-1123<70 mass %
5 mass %≤HFO-1234yf≤40 mass %
30 mass %<HFC-32≤44 mass %
The working fluid in the composition range (M) is a working fluid having respective properties of HFO-1123, HFO-1234yf and HFC-32 in a balanced manner, and having less defects of the respective components. That is, the working fluid is a working fluid in which an upper limit of GWP is reduced to 300 or less and durability is ensured, and which has a small temperature gradient smaller than 5.8 and has a relative coefficient of performance and a relative refrigeration capacity close to 1 when used for heat cycle, and thus, favorable cycle performance is obtained by the working fluid.
Within this range, the upper limit of the temperature gradient is decreased, and the lower limit of the product of the relative coefficient of performance and the relative refrigeration capacity is increased. In order to increase the relative coefficient of performance, it is more preferable to satisfy “8 mass %≤HFO-1234yf”. In addition, in order to increase the relative refrigeration capacity, it is more preferable to satisfy “HFO-1234yf≤35 mass %”.
In addition, it is preferable that another working fluid used in the present invention contains HFO-1123, HFC-134a, HFC-125 and HFO-1234yf With this composition, flammability of the working fluid can be controlled.
More preferably, in the working fluid containing HFO-1123, HFC-134a, HFC-125 and HFO-1234yf, the proportion of the total amount of HFO-1123, HFC-134a, HFC-125 and HFO-1234yf is more than 90 mass % and 100 mass % or less based on the entire amount of the working fluid, and the proportion of HFO-1123 is 3 mass % or more and 35 mass % or less, the proportion of HFC-134a is 10 mass % or more and 53 mass % or less, the proportion of HFC-12.5 is 4 mass % or more and 50 mass % or less, and the proportion of HFO-1234yf is 5 mass % or more and 50 mass % or less, based on the total amount of HFO-1123, HFC-134a, HFC-125 and HFO-1234yf. Such a working fluid is a working fluid being non-flammable, having excellent safety, having less influence on the ozone layer and global warming, and having excellent cycle performance when used for a heat cycle system.
Most preferably, in the working fluid containing HFO-1123, HFC-134a, HFC-125 and HFO-1234yf, the proportion of the total amount of HFO-1123, HFC-134a, HFC-125 and HFO-1234yf is more than 90 mass % and 100 mass % or less based on the entire amount of the working fluid, and the proportion of HFO-1123 is 6 mass % or more and 25 mass % or less, the proportion of HFC-134a is 20 mass % or more and 35 mass % or less, the proportion of HFC-125 is 8 mass % or more and 30 mass % or less, and the proportion of HFO-1234yf is 20 mass % or more and 50 mass % or less, based on the total amount of HFO-1123, HFC-134a, HFC-125 and HFO-1234yf. Such a working fluid is a working fluid being non-flammable, having more excellent safety, having much less influence on the ozone layer and global warming, and having more excellent cycle performance when used for a heat cycle system.
The working fluid used in a composition for a heat cycle system in the present invention may contain carbon dioxide, a hydrocarbon, a chlorofluoroolefin (CFO), a hydrochlorofluoroolefin (HCFO) and the like, other than the aforementioned optional component. As the other optional component, a component which has less influence on the ozone layer and has less influence on global warming is preferred.
Examples of the hydrocarbon include propane, propylene, cyclopropane, butane, isobutane, pentane, isopentane and the like.
One kind of such hydrocarbons may be used alone or two or more kinds of them may be used in combination.
When the working fluid contains a hydrocarbon, its content is less than 10 mass %, preferably from 1 to 5 mass %, and more preferably from 3 to 5 mass %, based on 100 mass % of the working fluid. When the content of the hydrocarbon is equal to or more than the lower limit, the solubility of a mineral refrigerator oil in the working fluid is more favorable.
Examples of the CFO include chlorofluoropropene, chlorofluoroethylene and the like. In order to easily control the flammability of the working fluid without significantly decreasing the cycle performance of the working fluid, the CFO is preferably 1,1-dichloro-2,3,3,3-tetrafluoropropene (CFO-1214ya), 1,3-dichloro-1,2,3,3-tetrafluoropropene (CFO-1214yb) or 1,2-dichloro-1,2-difluoroethylene (CFO-1112)
One kind of such CFOs may be used alone or two or more kinds of them may be used in combination.
When the working fluid contains the CFO, its content is less than 10 mass %, preferably from 1 to 8 mass %, and more preferably from 2 to 5 mass %, based on 100 mass % of the working fluid. When the content of the CFO is equal to or more than the lower limit, the flammability of the working fluid can be easily controlled. When the content of the CFO is equal to or less than the upper limit, favorable cycle performance is likely to be obtained.
Examples of the HCFO include hydrochlorofluoropropene, hydrochlorofluoroethylene and the like. In order to easily control the flammability of the working fluid without significantly decreasing the cycle performance of the working fluid, the HCFO is preferably 1-chloro-2,3,3,3-tetrafluoropropene (HCFO-1224yd) or 1-chloro-1,2-difluoroethyl ene (HCFO-1122).
One kind of such HCFOs may be used alone or two or more kinds of them may be used in combination.
In a case where the working fluid contains the HCFO, the content of the HCFO is less than 10 mass %, preferably from 1 to 8 mass %, and more preferably from 2 to 5 mass %, based on 100 mass % of the working fluid. When the content of the HCFO is equal to or more than the lower limit, the flammability of the working fluid can be easily controlled. When the content of the HCFO is equal to or less than the upper limit, favorable cycle performance is likely to be obtained.
When the working fluid used in the present invention contains the aforementioned other optional components, the total content of the other optional components in the working fluid is less than 10 mass %, preferably 8 mass % or less, and more preferably 5 mass % or less, based on 100 mass % of the working fluid.
Next, the schematic configuration of a refrigeration cycle apparatus in this embodiment is described.
In the refrigeration cycle apparatus 1, the following refrigeration cycle is repeated. First, a working fluid vapor A discharged from the evaporator 14 is compressed by the compressor 10 to form a high-temperature and high-pressure working fluid vapor B.
Then the working fluid vapor B discharged from the compressor 10 is cooled and liquefied by the fluid F in the condenser 12 to form a working fluid liquid C. At that time, the fluid F is heated to form a fluid F′ which is discharged from the condenser 12. Successively the working fluid liquid C discharged from the condenser 12 is expanded in the expansion mechanism 13 to form a working fluid liquid D which is in low temperature and low pressure. Successively the working fluid liquid D discharged from the expansion mechanism 13 is heated by the fluid E in the evaporator 14 to form a working fluid vapor A. At that time, the fluid E is cooled to form a fluid E′ which is discharged from the evaporator 14.
Next, the configuration of the compressor 10 is described.
As illustrated in
As illustrated in
As illustrated in
As illustrated in
The refrigeration cycle apparatus 1 uses the working fluid containing HFO-1123, as described above. When a certain level of ignition energy is applied to HFO-1123 in a high-temperature and high-pressure state, a chain of chemical reactions with heat generation may occur. Such a chemical reaction is called disproportionation reaction (self-decomposition reaction). The disproportionation reaction is a chemical reaction in which two or more molecules belonging to the same kind react with each other to generate two or more different kinds of products. When such a disproportionation reaction occurs within a refrigeration cycle apparatus, sudden temperature rise and pressure rise occur to lose the reliability of the refrigeration cycle apparatus.
Within the refrigeration cycle apparatus 1 described in
Before description about the configuration of the lead wire portion 72 in the compressor 10 of the refrigeration cycle apparatus 1 in this embodiment, description is first made about a general configuration of a lead wire portion in a compressor used in an existing refrigeration cycle apparatus, and problems in the configuration.
The lead wires 73a, 73b and 73c are bundled in their intermediate portions by a bundling member 74 such as a transparent tube. The lead wires 73a, 73b and 73c are bundled chiefly in order to improve the workability and to prevent the lead wires from abutting a sliding portion of the compressor to be thereby damaged.
Phases of voltages in the lead wires 73a, 73b and 73c differ from one another. Therefore, there is a large potential difference among the lead wires. When coatings of the lead wires are damaged for some reason at the parts where the lead wires 73a, 73b and 73c are bundled by the bundling member 74, the lead wires are short-circuited to generate discharge (spark). The coatings of the lead wires may be damaged, for example, because the coatings of the lead wires are melted by abnormal electric conduction to the compressor. During the operation of the refrigeration cycle apparatus, the lead wire portion 972 is exposed to the atmosphere of a working fluid which is in high temperature and high pressure. In a case where a working fluid containing HFO-1123 is used as the working fluid of the refrigeration cycle apparatus, when discharge is generated by short-circuiting among the lead wires 73a, 73b and 73c, ignition energy caused by the discharge is applied to the working fluid which is in high temperature and high pressure. Thus, disproportionation reaction of HFO-1123 may occur. In order to avoid the occurrence of disproportionation reaction of HFO-1123, it is necessary to avoid the discharge caused by short-circuiting in the lead wire portion 972.
Next, description is made about the configuration of the lead wire portion 72 in the compressor 10 of the refrigeration cycle apparatus 1 in this embodiment.
Since each of the parts where the lead wires 73a, 73b and 73c are bundled by the bundling member 74 is covered with the insulating materials 75 having heat resistance of 300° C. or more, the lead wires 73a, 73b and 73c can be inhibited from short-circuiting to thereby occur discharge even if the coatings in the parts where the lead wires 73a, 73b and 73c are bundled by the bundling member 74 are melted due to abnormal electric conduction to the compressor. As a result, when the working fluid containing HFO-1123 is used, it is possible to effectively avoid the occurrence of disproportionation reaction of HFO-1123.
Embodiment 2 of the present invention is described below with reference to the drawings.
A refrigeration cycle apparatus in this embodiment is the same as the refrigeration cycle apparatus 1 described in Embodiment 1 with reference to
As illustrated in
The lead wires 73a, 73b and 73c are bundled by the insulating member 176 so as to be separated from one another by a distance enough not to bring them into contact with one another. Thus, the lead wires 73a, 73b and 73c can be prevented from short-circuiting due to contact with one another to thereby occur discharge even if the coatings of the lead wires 73a, 73b and 73c are melted due to abnormal electric conduction to the compressor. As a result, it is possible to effectively avoid occurrence of disproportionation reactions of HFO-1123 when a working fluid containing the HFO-1123 is used.
The shape of the insulating member 176 is not limited to the cylindrical shape. For example, it may be a spherical shape. In addition, the number of insulating members 176 to be attached to the lead wires 73a, 73b and 73c is not limited to one but may be plural as long as the lead wires can be separated from one another by a distance enough not to bring them into contact with one another.
Embodiment 3 of the present invention is described below with reference to the drawings.
A refrigeration cycle apparatus in this embodiment is the same as the refrigeration cycle apparatus 1 described in Embodiment 1 with reference to
In the lead wire portion 972 of the compressor used in the existing refrigeration cycle apparatus illustrated in
As described above, the refrigeration cycle apparatus 1 uses the working fluid containing HFO-1123. When the insertion terminals 78a, 78b and 78c come into contact with one another to thereby occur discharge during the operation of the refrigeration cycle apparatus, there is a fear that ignition energy caused by the discharge may be applied to the working fluid under high temperature and high pressure so as to cause disproportionation reactions of HFO-1123 inside the compressor 10 illustrated in
The material of the connector 277 may be a wire material which is 180(H), 200(N), 220(R), or 250 in thermal class defined in JIS C4003. Examples of the main material thereof include a material having high heat resistance, such as mica, asbestos, alumina, silica glass, quartz, magnesium oxide, polytetrafluoroethylene, and silicone rubber. In addition, examples of the main material thereof include polyimide resin, polybenzimidazole resin, polyether ether ketone resin, polyphenylene sulfide resin, nylon resin, polybutylene terephthalate resin, polyether imide resin, polyamide imide resin, allyl resin, diallyl phthalate resin, acetyl cellulose resin, cellulose acetate resin, and the like. One kind of those heat resistant materials may be used alone, but it is preferable that two or more kinds of them are used in combination in order to provide excellent heat resistance.
In addition, silicon resin may be used as an impregnation coating material or an insulating treatment material used for manufacturing the heat resistant material wires. When the impregnation coating material or the insulating treatment material is used together with the aforementioned heat resistant materials, an auxiliary function such as improvement in insulation can be expressed.
When an insulating material having heat resistance of 300° C. or more is used as the material of the connector 277, it is possible to avoid melting of the connector 277 due to abnormal electric conduction to the compressor. It is therefore possible to avoid contact among the insertion terminals 78a, 78b and 78c at the front ends of the lead wires 73a, 73b and 73c and the occurrence of discharge caused thereby. As a result, it is possible to effectively avoid occurrence of disproportionation reactions of HFO-1123 when a working fluid containing the HFO-1123 is used.
Embodiment 4 of the present invention is described below with reference to the drawings.
A refrigeration cycle apparatus in this embodiment is the same as the refrigeration cycle apparatus 1 described in Embodiment 1 with reference to
As described above, the refrigeration cycle apparatus 1 uses the working fluid containing HFO-1123. When the insertion terminals 78a, 78b and 78c come into contact with one another to thereby occur discharge during the operation of the refrigeration cycle apparatus, there is a possibility that ignition energy caused by the discharge may be applied to the working fluid under high temperature and high pressure so as to lead to occurrence of disproportionation reactions of HFO-1123 inside the compressor 10 illustrated in
In comparison with the lead wire portion 972 of the compressor used in the existing refrigeration cycle apparatus illustrated in
When the lead wires 73a, 73b and 73c are inserted into the connector 377 in directions of being separate from one another at angles, respectively, the distances among the insertion terminals can be increased so that the insertion terminals 78a, 78b and 78c at the front ends of the lead wires 73a, 73b and 73c can be inhibited from coming into contact with one another to thereby occur discharge. As a result, it is possible to effectively avoid occurrence of disproportionation reactions of HFO-1123 when a working fluid containing the HFO-1123 is used.
The present invention is not limited to the aforementioned embodiments, but may be changed suitably without departing from the gist of the present invention. For example, although the aforementioned embodiments are described on the assumption that the compressor of the refrigeration cycle apparatus is a rotary compressor, the present invention is not limited thereto. For example, the compressor may be a scroll compressor. Although the motor of the driving unit in the compressor is a three-phase induction motor in the aforementioned embodiments, it may be, for example, a brushless DC (Direct Current) motor.
In addition, the embodiments may be combined with one another suitably. For example, Embodiment 3 or Embodiment 4 may be combined with Embodiment 1. Embodiment 3 or Embodiment 4 may be combined with Embodiment 2.
Although the present invention has been described in detail and along its specific embodiments, it is obvious for those skilled in the art that various changes or modifications can be made on the present invention without departing from the spirit and scope of the present invention. The present application is based on a Japanese patent application No. 2016-16081 filed on Jan. 29, 2016, the contents of which are incorporated herein by reference.
| Number | Date | Country | Kind |
|---|---|---|---|
| 2016-016081 | Jan 2016 | JP | national |
| Number | Date | Country | |
|---|---|---|---|
| Parent | PCT/JP2017/002496 | Jan 2017 | US |
| Child | 16044972 | US |
