Technical Field
[0001] The present invention relates to a heat exchange unit. More particularly, the present
invention relates to a heat exchange unit for use in refrigerating cycle apparatus.
Background Art
[0002] Working media (hereinafter referred to also as "refrigerants") based on a hydrofluorocarbon
(HFC) are in extensive use in refrigerating cycle apparatus such as air conditioners
and refrigerators. However, it has been pointed out that HFCs have large values of
global warming potential (GWP) and may be a cause of global warming. It is hence of
urgent necessity to develop a working medium for refrigerating cycles which less affects
the ozone layer and has a small value of global warming potential. Working media for
refrigerating cycles which include a hydrofluoroolefin (HFO) having a carbon-carbon
double bond which is apt to be cleaved by OH radicals present in the air are being
investigated as working media which less affect the ozone layer and less affect the
global warming. Patent Document 1 describes a refrigerating cycle apparatus employing
a working medium including 1,1,2-trifluoroethylene (HFO-1123).
Prior Art Document
Patent Document
Summary of the Invention
Problem that the Invention is to Solve
[0004] There is a case where HFO-1123 in a high-temperature high-pressure state, upon reception
of energy, undergoes an exothermic chemical reaction called a disproportionation reaction
(self-decomposition reaction), which occurs like a chain reaction. A disproportionation
reaction is a chemical reaction in which two or more molecules of the same kind react
with each other to yield two or more different products. For refrigerating cycle apparatus
employing working media including HFO-1123, it is therefore necessary to inhibit the
occurrence of such a disproportionation reaction.
[0005] In view of that problem, an object of the present invention is to provide a heat
exchange unit in which HFO-1123 can be inhibited from undergoing a disproportionation
reaction.
Means for Solving the Problem
[0006] The present invention provides, in accordance with a first mode thereof, a heat exchange
unit including: a compressor configured to compress a working medium that circulates
through a refrigerating cycle, the working medium including 1,1,2-trifluoroethylene;
a heat exchanger provided in the refrigerating cycle; and a heat dissipation means
configured to dissipate heat generated in the compressor without using the working
medium.
[0007] The present invention provides, in accordance with a second mode thereof, a heat
exchange unit that is the heat exchange unit described above which further includes:
a blower configured to increase an air flow flowing along a surface of the heat exchanger
to enhance heat exchange in the heat exchanger and a partition that separates a space
where the blower is provided from a space where the compressor is provided. The partition
has a vent hole formed therein at a position corresponding to the compressor, and
the heat dissipation means includes the blower so that an air flow sent from the blower
is used to dissipate the heat of the compressor.
[0008] The present invention provides, in accordance with a third mode thereof, a heat exchange
unit that is the heat exchange unit described above including an air deflector that
directs a part of the air flow sent from the blower toward the compressor.
[0009] The present invention provides, in accordance with a fourth mode thereof, a heat
exchange unit that is the heat exchange unit described above wherein the blower includes
a wind direction changing part that changes the direction of wind of the blower toward
the compressor
[0010] The present invention provides, in accordance with a fifth mode thereof, a heat
exchange unit that is the heat exchange unit described above which includes: a detecting
part that detects a temperature of the working medium discharged from the compressor;
a determination part that determines whether or not the temperature of the working
medium is higher than a predetermined temperature; and a first control part that controls
the wind direction changing part in accordance with a determination made by the determination
part. In a case where the temperature of the working medium is higher than the predetermined
temperature, the first control part controls the wind direction changing part so that
wind direction of the blower is directed toward the compressor.
[0011] The present invention provides, in accordance with a sixth mode thereof, a heat exchange
unit that is the heat exchange unit described above wherein a heat sink, as the heat
dissipation means, is provided to the compressor, wherein the heat sink dissipates
the heat generated in the compressor.
[0012] The present invention provides, in accordance with a seventh mode thereof, a heat
exchange unit that is the heat exchange unit described above which further includes,
as the heat dissipation means, a drain-water supply unit that supplies drain water
yielded in the refrigerating cycle to a surface of the compressor to cool the compressor.
[0013] The present invention provides, in accordance with an eighth mode thereof, a heat
exchange unit that is the heat exchange unit described above wherein the drain-water
supply unit includes: a drain-water reservoir for reserving therein drain water yielded
in the refrigerating cycle; a detecting part that detects a temperature of the working
medium discharged from the compressor; a determination part that determines whether
or not the temperature of the working medium is higher than a predetermined temperature;
an electromagnetic valve that performs switching regarding the supply of the drain
water from the drain-water reservoir to the surface of the compressor, and a second
control part that controls the electromagnetic valve in accordance with a determination
made by the determination part. In a case where the temperature of the working medium
is higher than the predetermined temperature, the second control part opens the electromagnetic
valve to supply the drain water from the drain-water reservoir to the surface of the
compressor.
Effect of the Invention
[0014] The present invention can provide a heat exchange unit in which HFO-1123 can be inhibited
from undergoing a disproportionation reaction.
Brief Description of the Drawings
[0015]
FIG. 1 is a view for explaining a refrigerating cycle apparatus.
FIG. 2 is a view for explaining a refrigerating cycle apparatus.
FIG. 3A is a top plan view showing a heat exchange unit according to embodiment 1.
FIG. 3B is a front view showing the heat exchange unit according to embodiment 1.
FIG. 3C is a side view showing the heat exchange unit according to embodiment 1.
FIG. 4 is a side view showing another heat exchange unit according to embodiment 1.
FIG. 5 is a top plan view showing a heat exchange unit according to embodiment 2.
FIG. 6 is a front view showing a heat exchange unit according to embodiment 3.
FIG. 7A is a top plan view for explaining an operation of the heat exchange unit according
to embodiment 3.
FIG. 7B is a top plan view for explaining an operation of the heat exchange unit according
to embodiment 3.
FIG. 8 is a top plan view showing a heat exchange unit according to embodiment 4.
FIG. 9 is a side view showing a heat exchange unit according to embodiment 5.
Modes for Carrying Out the Invention
[0016] Embodiments of the present invention are explained below by reference to the drawings.
[0017] First, the working medium (refrigerant) to be used in the refrigerating cycle apparatus
of the invention is explained.
<Working Medium>
(HFO-1123)
[0018] The working medium to be used in the invention includes 1,1,2-trifluoroethylene (HFO-1123).
The working-medium characteristics of HFO-1123 are shown in Table 1 in terms of comparison
with those of, in particular, R410A (pseudoazeotropic-mixture working medium composed
of HFC-32 and HFC-125 in a mass ratio of 1:1). Cycle performance is indicated by the
coefficient of performance and refrigerating capacity which are determined by the
methods that will be described later. The coefficient of performance and refrigerating
capacity of HFO-1123 are given as relative values (hereinafter referred to as "relative
coefficient of performance" and "relative refrigerating capacity") with respect to
those of R410A as a reference (1.000). The global warming coefficient (GWP) is a value
for 100 years which is defined in Intergovernmental Panel on Climate Change (IPCC),
Fourth assessment report (year 2007) or is determined by the method. In this description,
values of GWP are such values unless otherwise indicated. In the case of a working
medium constituted of a mixture, temperature glide is an important factor for evaluating
the working medium; the smaller the value thereof, the more the working medium is
preferred.
[Table 1]
[0019]
Table 1
| |
R410A |
HFO-1123 |
| Relative coefficient of performance |
1.000 |
0.921 |
| Relative refrigerating capacity |
1.000 |
1.146 |
| Temperature glide [°C] |
0.2 |
0 |
| GWP |
2088 |
0.3 |
[Optional Ingredients]
[0020] The working medium to be used in the invention preferably includes HFO-1123. The
working medium may contain any desired compounds commonly used as working media, besides
HFO-1123 so long as the inclusion thereof does not lessen the effect of the invention.
Examples of such optionally usable compounds (optional ingredients) include HFCs,
HFOs (HFCs having a carbon-carbon double bond) other than HFO-1123, and other ingredients
which vaporize and liquefy together with HFO-1123. Preferred optional ingredients
are HFCs and HFOs (HFCs having a carbon-carbon double bond) other than HFO-1123.
[0021] Preferred optional ingredients are compounds which, when used in heat cycling in
combination with HFO-1123, have the function of further heightening the relative coefficient
of performance and the relative refrigerating capacity and which, despite this, can
make the GWP and the temperature glide remain in acceptable ranges. In the case where
the working medium contains such a compound in combination with HFO-1123, not only
this working medium retains a low GWP and has better cycle performance but also the
temperature glide exerts little influence.
(Temperature Glide)
[0022] A working medium including, for example, HFO-1123 and an optional ingredient has
a considerable temperature glide except for the case where the HFO-1123 and the optional
ingredient are present as an azeotropic composition. The temperature glide of the
working medium varies depending on the kind of the optional ingredient and the mixing
ratio of HFO-1123 and optional ingredient.
[0023] In the case of using a mixture as the working medium, the mixture usually preferably
is an azeotropic mixture or a pseudoazeotropic mixture such as R410A. Non-azeotropic
compositions have a problem in that the compositions change in makeup when charged
into refrigerators or air conditioners from pressure vessels. In addition, in the
case where such a refrigerant has leaked from the refrigerator or air conditioner,
there is an extremely high possibility that the refrigerant within the refrigerator
or air conditioner might have changed in makeup and it is difficult to recover the
initial makeup of the refrigerant. Meanwhile, in the case where an azeotropic or pseudoazeotropic
mixture is used, these problems can be avoided.
[0024] "Temperature glide" is generally used as an index to the usability of working media
which are mixtures. Temperature glide is defined as the property of differing in temperature
between initiation and termination of, for example, vaporization in a vaporizer, or
condensation in a condenser. The azeotropic mixtures have a temperature glide of 0,
and pseudoazeotropic mixtures have temperature glides close to 0, like R410A, which
has a temperature glide of 0.2.
[0025] In case where the temperature glide is large, this working medium has a lowered temperature
at the inlet of the vaporizer to pose a problem in that frosting is highly likely
to occur. Furthermore, in a heat cycle system, the working medium and the heat source
fluid, such as water or air, are generally caused to flow countercurrently in a heat
exchanger in order to improve the heat exchange efficiency. Since the heat source
fluid has a small temperature difference in the heat cycle system which is being stably
operated, it is difficult to obtain a heat cycle system having a satisfactory energy
efficiency with a non-azeotropic mixture medium having a large temperature glide.
Consequently, in the case where a mixture is to be used as a working medium, this
working medium is desired to have an appropriate temperature glide.
(HFC)
[0026] It is preferred to select an HFC as an optional ingredient from those standpoints.
HFCs are known to have higher GWPs than HFO-1123. It is hence preferable that an HFC
to be used in combination with HFO-1123 is suitably selected from the standpoints
of enabling the working medium to have improved cycle performance and retain a temperature
glide within an appropriate range and, in particular, of making the working medium
have a GWP within an acceptable range.
[0027] Specifically, preferred HFCs which less affect the ozone layer and less affect global
warming are HFCs having a carbon number of from 1 to 5. These HFCs may be linear,
branched, or cyclic.
[0028] Examples of such HFCs include HFC-32, difluoroethane, trifluoroethane, tetrafluoroethane,
HFC-125, pentafluoropropane, hexafluoropropane, heptafluoropropane, pentafluorobutane,
and heptafluorocyclopentane.
[0029] Preferred of these HFCs, from the standpoints of reduced influence on the ozone layer
and excellent refrigerating cycle properties, are 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. More preferred are HFC-32, HFC-152a, HFC-134a, and HFC-125.
[0030] One HFC may be used alone, or two or more HFCs may be used in combination.
[0031] The content of an HFC in the working medium (100% by mass) can be selected at will
in accordance with the properties required of the working medium. For example, in
the case of a working medium composed of HFO-1123 and HFC-32, this working medium
has an improved coefficient of performance and improved refrigerating capacity in
the case where the content of HFC-32 is in the range of 1 to 99% by mass. In the case
of a working medium composed of HFO-1123 and HFC-134a, this working medium has an
improved coefficient of performance in the case where the content of HFC-134a is in
the range of 1 to 99% by mass.
[0032] The GWPs of the preferred HFCs are as follows. The GWP of HFC-32 is 675, that of
HFC-134a is 1,430, and that of HFC-125 is 3,500. From the standpoint of obtaining
a working medium having a reduced GWP, HFC-32 is the most preferred optional HFC ingredient.
[0033] HFO-1123 and HFC-32 are capable of forming a nearly azeotropic mixture, or a pseudoazeotropic
mixture, when used in proportions in the range of 99/1 to 1/99 in terms of mass ratio.
Mixtures of the two have temperature glides close to 0 substantially irrespective
of the proportions. In this respect also, HFC-32 is advantageous as an HFC to be used
in combination with HFO-1123.
[0034] In the case of using HFC-32 in combination with HFO-1123 as the working medium to
be used in the invention, the content of HFC-32 in the working medium, the amount
of which is taken as 100% by mass, is specifically preferably 20% by mass or more,
more preferably 20 to 80% by mass, even more preferably 40 to 60% by mass.
[0035] In the case where the working medium to be used in the invention contains, for example,
HFO-1123, preferred HFOs other than HFO-1123 are HFO-1234yf (GWP=4), HFO-1234ze(E),
and HFO-1234ze(Z) (the (E) and (Z) isomers each have GWP=6), because these HFOs each
have a high critical temperature and are excellent in terms of durability and the
coefficient of performance. More preferred are HFO-1234yf and HFO-1234ze(E). One HFO
other than HFO-1123 may be used alone, or two or more HFOs other than HFO-1123 may
be used in combination. The content of HFOs other than HFO-1123 in the working medium
(100% by mass) can be selected at will in accordance with the properties required
of the working medium. For example, in the case of a working medium composed of HFO-1123
and either HFO-1234yf or HFO-1234ze, this working medium has an improved coefficient
of performance in the case where the content of HFO-1234yf or HFO-1234ze is in the
range of 1 to 99% by mass.
[0036] In the case where the working medium to be used in the invention includes HFO-1123
and HFO-1234yf, a preferred composition range is shown below as composition range
(S).
[0037] In the expressions indicating the composition range (S), the abbreviation of each
compound shows the proportion (% by mass) of the compound to the total amount of the
HFO-1123, HFO-1234yf, and other ingredients (HFC-32, etc.).
<Composition Range (S)>
[0038]
HFO-1123 + HFO-1234yf ≥ 70 mass%
95 mass% ≥ HFO-1123/(HFO-1123 + HFO-1234yf) ≥ 35 mass%
[0039] The working medium which satisfies the composition range (S) has an exceedingly low
GWP and a small temperature glide. This working medium can exhibit high refrigerating
cycle performance which renders the working medium usable as a substitute for the
conventional R410A from the standpoints of the coefficient of performance, refrigerating
capacity, and critical temperature.
[0040] In the working medium satisfying the composition range (S), the proportion of HFO-1123
to the sum of HFO-1123 and HFO-1234yf is more preferably 40 to 95% by mass, even more
preferably 50 to 90% by mass, especially preferably 50 to 85% by mass, most preferably
60 to 85% by mass.
[0041] The total content of HFO-1123 and HFO-1234yf in the working medium, the amount of
which is taken as 100% by mass, is more preferably 80 to 100% by mass, even more preferably
90 to 100% by mass, especially preferably 95 to 100% by mass.
[0042] The working medium to be used in the invention preferably includes HFO-1123, HFC-32,
and HFO-1234yf. In the case of the working medium including HFO-1123, HFO-1234yf,
and HFC-32, a preferred composition range (P) is as follows.
[0043] In the expressions indicating the composition range (P), the abbreviation of each
compound shows the proportion (% by mass) of the compound to the total amount of the
HFO-1123, HFO-1234yf, and HFC-32. This applies to composition range (R), composition
range (L), and composition range (M). In the composition range shown below, it is
preferable that the sum of the specifically shown contents of HFO-1123, HFO-1234yf,
and HFC-32 is higher than 90% by mass but not higher than 100% by mass based on the
whole amount of the working medium for heat cycling.
<Composition Range (P)>
[0044]
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%
[0045] The working medium having the composition is a working medium in which the properties
possessed by HFO-1123, HFO-1234yf, and HFC-32 are exhibited while attaining a satisfactory
balance thereamong and in which the drawbacks of these ingredients have been mitigated.
Namely, this working medium has an exceedingly low GWP and, when used in heat cycling,
has a small temperature glide and a certain degree of ability and efficiency, thereby
attaining satisfactory cycle performance. It is preferable that the sum of HFO-1123
and HFO-1234yf is 70% by mass or more of the total amount of HFO-1123, HFO-1234yf,
and HFC-32.
[0046] A more preferred composition of the working medium to be used in the invention is
one which contains 30 to 70% by mass HFO-1123, 4 to 40% by mass HFO-1234yf, and 0
to 30% by mass HFC-32, based on the total amount of the HFO-1123, HFO-1234yf, and
HFC-32 and in which the content of HFO-1123 is 70% by mole or less based on the whole
working medium. The working medium having a composition within that range shows higher
effects in terms of the properties shown above and is a highly durable working medium
in which the HFO-1123 is inhibited from undergoing a self-decomposition reaction.
From the standpoint of the relative coefficient of performance, the content of HFC-32
is preferably 5% by mass or more, more preferably 8% by mass or more.
[0047] In the case where the working medium to be used in the invention includes HFO-1123,
HFO-1234yf, and HFC-32, another preferred composition is as follows. In the case where
the content of HFO-1123 is 70% by mole or less based on the whole working medium,
the HFO-1123 is inhibited from undergoing a self-decomposition reaction and this working
medium has high durability.
[0048] A more preferred composition range (R) is shown below.
<Composition Range (R)>
[0049]
10 mass% ≤ HFO-1123 < 70 mass%
0 mass% < HFO-1234yf ≤ 50 mass%
30 mass% < HFC-32 ≤ 75 mass%
[0050] The working medium having the composition is a working medium in which the properties
possessed by HFO-1123, HFO-1234yf, and HFC-32 are exhibited while attaining a satisfactory
balance thereamong and in which the drawbacks of these ingredients have been mitigated.
Namely, this working medium has a low GWP and intact durability and has a small temperature
glide and high ability and efficiency when used in heat cycling, thereby attaining
satisfactory cycle performance.
[0051] A preferred range for the working medium of the invention which has 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%
[0052] The working medium having the composition is a working medium in which the properties
possessed by HFO-1123, HFO-1234yf, and HFC-32 are exhibited while attaining a satisfactory
balance thereamong and in which the drawbacks of these ingredients have been mitigated.
Namely, this working medium has a low GWP and intact durability and has a smaller
temperature glide and higher ability and efficiency when used in heat cycling, thereby
attaining satisfactory cycle performance.
[0053] A more preferred range (L) for the working medium of the invention which has the
composition range (R) is shown below. The composition range (M) is even more preferred.
<Composition Range (L)>
[0054]
10 mass% ≤ HFO-1123 < 70 mass%
0 mass% < HFO-1234yf ≤ 50 mass%
30 mass% < HFC-32 ≤ 44 mass%
<Composition Range (M)>
[0055]
20 mass% ≤ HFO-1123 < 70 mass%
5 mass% ≤ HFO-1234yf ≤ 40 mass%
30 mass% < HFC-32 ≤ 44 mass%
[0056] The working medium having the composition range (M) is a working medium in which
the properties possessed by HFO-1123, HFO-1234yf, and HFC-32 are exhibited while attaining
a highly satisfactory balance thereamong and in which the drawbacks of these ingredients
have been mitigated. Namely, this working medium is a working medium which has a GWP
as low as 300 or less at the most and has intact durability and which, when used in
heat cycling, has a temperature glide as small as less than 5.8 and has a relative
coefficient of performance and a relative refrigerating capacity both close to 1,
thereby attaining satisfactory cycle performance.
[0057] In the case where the composition is within that range, the temperature glide has
a reduced upper limit and the value of (relative coefficient of performance)×(relative
refrigerating capacity) has an increased lower limit. From the standpoint of attaining
a large value of the relative coefficient of performance, the proportion of HFO-1234yf
is more preferably 8% by mass or larger. From the standpoint of attaining high relative
refrigerating capacity, the proportion of HFO-1234yf is more preferably 35% by mass
or less.
[0058] Another preferred working medium for use in the invention preferably includes HFO-1123,
HFC-134a, HFC-125, and HFO-1234yf. This composition is effective in making the working
medium have reduced combustibility.
[0059] A more preferred working medium is one which includes HFO-1123, HFC-134a, HFC-125,
and HFO-1234yf and in which: the total proportion of HFO-1123, HFC-134a, HFC-125,
and HFO-1234yf to the whole working medium is larger than 90% by mass and 100% by
mass or less; the proportion of HFO-1123 to the sum of HFO-1123, HFC-134a, HFC-125,
and HFO-1234yf is 3% by mass or more and 35% by mass or less; the proportion of HFC-134a
to said sum is 10% by mass or more and 53% by mass or less; the proportion of HFC-125
to said sum is 4% by mass or more and 50% by mass or less; and the proportion of HFO-1234yf
to said sum is 5% by mass or more and 50% by mass or less. This working medium is
noncombustible and highly safe, less affects the ozone layer and global warming, and
can have better cycle performance when used in heat cycle systems.
[0060] A most preferred working medium is one which includes HFO-1123, HFC-134a, HFC-125,
and HFO-1234yf and in which: the total proportion of HFO-1123, HFC-134a, HFC-125,
and HFO-1234yf to the whole working medium is larger than 90% by mass and 100% by
mass or less; the proportion of HFO-1123 to the sum of HFO-1123, HFC-134a, HFC-125,
and HFO-1234yf is 6% by mass or more and 25% by mass or less; the proportion of HFC-134a
to said sum is 20% by mass or more and 35% by mass or less; the proportion of HFC-125
to said sum is 8% by mass or more and 30% by mass or less; and the proportion of HFO-1234yf
to said sum is 20% by mass or more and 50% by mass or less. This working medium is
noncombustible and even safer, even less affects the ozone layer and global warming,
and can have even better cycle performance when used in heat cycle systems.
(Other Optional Ingredients)
[0061] The working medium to be used as the composition for use in the heat cycle system
of the invention may contain carbon dioxide, hydrocarbons, chlorofluoroolefins (CFOs),
hydrochlorofluoroolefins (HCFOs), etc. besides the optional ingredients shown above.
Such other optional ingredients preferably are ingredients which less affect the ozone
layer and less affect global warming.
[0062] Examples of the hydrocarbons include propane, propylene, cyclopropane, butane, isobutane,
pentane, and isopentane.
[0063] One hydrocarbon may be used alone, or two or more hydrocarbons may be used in combination.
[0064] In the case where the working medium contains a hydrocarbon, the content thereof
based on the working medium, the amount of which is taken as 100% by mass, is less
than 10% by mass, preferably 1 to 5% by mass, more preferably 3 to 5% by mass. In
the case where the working medium has a hydrocarbon content not less than the lower
limit, mineral-oil-based refrigerating oils have better solubility in this working
medium.
[0065] Examples of the CFOs include chlorofluoropropenes and chlorofluoroethylenes. From
the standpoint of easily reducing the combustibility of the working medium without
considerably lowering the cycle performance of the working medium, preferred CFOs
are 1,1-dichloro-2,3,3,3-tetrafluoropropene (CFO-1214ya), 1,3-dichloro-1,2,3,3-tetrafluoropropene
(CFO-1214yb), and 1,2-dichloro-1,2-difluoroethylene (CFO-1112).
[0066] One CFO may be used alone, or two or more CFOs may be used in combination.
[0067] In the case where the working medium contains a CFO, the content thereof based on
the working medium, the amount of which is taken as 100% by mass, is less than 10%
by mass, preferably 1 to 8% by mass, more preferably 2 to 5% by mass. In the case
where the CFO content is not less than the lower limit, the combustibility of this
working medium is easy to be reduced. In the case where the CFO content is not higher
than the upper limit, satisfactory cycle performance is easy to be obtained.
[0068] Examples of the HCFOs include hydrochlorofluoropropenes and hydrochlorofluoroethylenes.
From the standpoint of easily reducing the combustibility of the working medium without
considerably lowering the cycle performance of the working medium, preferred HCFOs
are 1-chloro-2,3,3,3-tetrafluoropropene (HCFO-1224yd) and 1-chloro-1,2-difluoroethylene
(HCFO-1122).
[0069] One HCFO may be used alone, or two or more HCFOs may be used in combination.
[0070] In the case where the working medium contains an HCFO, the content of the HCFO in
the working medium, the amount of which is taken as 100% by mass, is less than 10%
by mass, preferably 1 to 8% by mass, more preferably 2 to 5% by mass. In the case
where the HCFO content is not less than the lower limit, the combustibility of this
working medium is easy to be reduced. In the case where the HCFO content is not higher
than the upper limit, satisfactory cycle performance is easy to be obtained.
[0071] In the case where the working medium to be used in the invention contains other optional
ingredients such as those shown above, the total content of the other optional ingredients
in the working medium, the amount of which is taken as 100% by mass, is less than
10% by mass, preferably 8% by mass or less, more preferably 5% by mass or less.
<Refrigerating Cycle Apparatus>
[0072] Next, refrigerating cycle apparatus including heat exchange units according to the
present invention are explained. FIG. 1 is a view for explaining a refrigerating cycle
apparatus including a heat exchange unit according to the present invention.
[0073] As FIG. 1 shows, the refrigerating cycle apparatus 100 includes a compressor 11,
a heat exchanger 12, an expansion valve 13, a heat exchanger 14, an accumulator 15,
a selector valve 16, and blowers 17 and 21. Although FIG. 1 shows an example including
a heat exchange unit 1 which includes the compressor 11, heat exchanger 12, expansion
valve 13, accumulator 15, selector valve 16, and blower 21, the heat exchange unit
1 according to the present invention is only required to include at least the compressor
11 and the heat exchanger 12.
[0074] The refrigerating cycle apparatus 100 is, for example, an air conditioner, a refrigerator,
or the like. For example, in the case where the refrigerating cycle apparatus 100
is used as an air conditioner, the heat exchange unit 1 corresponds to an outdoor
unit and the heat exchanger 14 corresponds to the heat exchanger included in an indoor
unit.
[0075] The refrigerating cycle apparatus 100 shown in FIG. 1 is in such a state that the
heat exchanger 12 is dissipating heat and the heat exchanger 14 is absorbing heat.
In the case where the refrigerating cycle apparatus 100 is, for example, an air conditioner,
FIG. 1 shows the air conditioner which is in the state of performing a cooling operation
or a defrosting operation.
[0076] In the refrigerating cycle apparatus 100 shown in FIG. 1, a working medium including
HFO-1123 is circulated through the compressor 11, heat exchanger 12, expansion valve
13, heat exchanger 14, and accumulator 15 in this order to form a refrigerating cycle.
Specifically, the high-temperature high-pressure working medium (vapor) discharged
from the compressor 11 is supplied to the heat exchanger 12 via the selector valve
16. The working medium supplied to the heat exchanger 12 undergoes heat dissipation
by emitting heat to the air surrounding the heat exchanger 12 and condenses thereby.
By providing a blower 21 in the vicinity of the heat exchanger 12, an air flow (that
is, the air flow amount) flowing along a surface of the heat exchanger 12 can be enhanced,
and heat exchange (heat dissipation) in the heat exchanger 12 can be enhanced. The
working medium which has become liquid through the condensation is supplied from the
heat exchanger 12 to the expansion valve 13 and depressurized by the expansion valve
13.
[0077] The working medium depressurized by the expansion valve 13 is supplied to the heat
exchanger 14 and expands in the heat exchanger 14 to come to have a low temperature
and a low pressure, thereby lowering the surface temperature of the heat exchanger
14. The heat exchanger 14 having a lowered surface temperature absorbs heat from the
surrounding air, thereby cooling the air surrounding the heat exchanger 14. By providing
a blower 17 in the vicinity of the heat exchanger 14, an air flow flowing along a
surface of the heat exchanger 14 can be increased, and heat exchange (heat absorption)
in the heat exchanger 14 can be enhanced. After the heat absorption in the heat exchanger
14, the low-temperature gaseous working medium returns to the compressor 11 via the
selector valve 16 and the accumulator 15. The working medium which is entering the
accumulator 15 has partly liquefied, and the liquefied portion of the working medium
is reserved in the accumulator 15.
[0078] Meanwhile, FIG. 2 shows a refrigerating cycle apparatus 200 which is in such a state
that a heat exchanger 12 is absorbing heat and a heat exchanger 14 is dissipating
heat. In the case where the refrigerating cycle apparatus 200 is, for example, an
air conditioner, FIG. 2 shows the air conditioner which is in the state of performing
a heating operation.
[0079] In the refrigerating cycle apparatus 200 shown in FIG. 2, a working medium including
HFO-1123 is circulated through a compressor 11, the heat exchanger 14, an expansion
valve 13, the heat exchanger 12, and an accumulator 15 in this order to form a refrigerating
cycle. The direction of circulation of the working medium in the refrigerating cycle
apparatus 200 shown in FIG. 2 is reverse to that in the refrigerating cycle apparatus
100 shown in FIG. 1. The direction of circulation of the working medium can be selected
by operating the selector valve 16.
[0080] As FIG. 2 shows, the high-temperature high-pressure working medium (vapor) discharged
from the compressor 11 is supplied to the heat exchanger 14 via the selector valve
16. The working medium supplied to the heat exchanger 14 undergoes heat dissipation
by emitting heat to the air surrounding the heat exchanger 14 and condenses thereby.
By providing a blower 17 in the vicinity of the heat exchanger 14, an air flow can
be made to flow in an increased amount along a surface of the heat exchanger 14, and
heat exchange (heat dissipation) in the heat exchanger 14 can be enhanced. The working
medium which has become liquid through the condensation is supplied from the heat
exchanger 14 to the expansion valve 13 and depressurized by the expansion valve 13.
[0081] The working medium depressurized by the expansion valve 13 is supplied to the heat
exchanger 12 and expands in the heat exchanger 12 to come to have a low temperature
and a low pressure, thereby lowering the surface temperature of the heat exchanger
12. The heat exchanger 12 having a lowered surface temperature absorbs heat from the
surrounding air. By providing a blower 21 in the vicinity of the heat exchanger 12,
an air flow flowing along a surface of the heat exchanger 12 can be increased, and
heat exchange (heat absorption) in the heat exchanger 12 can be enhanced. After the
heat absorption in the heat exchanger 12, the low-temperature gaseous working medium
returns to the compressor 11 via the selector valve 16 and the accumulator 15. The
working medium which is entering the accumulator 15 has partly liquefied, and the
liquefied portion of the working medium is reserved in the accumulator 15.
<Outline of the Present Invention>
[0082] An outline of the present invention is predetermined below.
[0083] The heat exchange unit according to the present invention includes: a compressor
configured to compress a working medium that circulates through a refrigerating cycle,
the working medium including 1,1,2-trifluoroethylene, a heat exchanger provided in
the refrigerating cycle, and a heat dissipation means configured to dissipate heat
generated in the compressor without using the working medium. Since the heat exchange
unit according to the present invention includes a heat dissipation means configured
to dissipate heat generated in the compressor, it is possible to enhance cooling of
the compressor. Consequently, the HFO-1123 can be inhibited from undergoing a disproportionation
reaction.
[0084] In embodiments 1 to 3, which will be explained below, a blower 21 (see FIG. 3A) is
used to configure a heat dissipation means. Namely, an air flow sent from the blower
21 is used to dissipate the heat of the compressor.
[0085] In embodiment 4, which will be explained later, a heat sink 51 (see FIG. 8) is used
to configure a heat dissipation means. Namely, by providing the heat sink 51 to a
compressor 11, the heat generated in the compressor is dissipated.
[0086] In embodiment 5, which will be explained later, a drain-water supply unit (see the
drain-water reservoir 62, etc. shown in FIG. 9) is used to configure a heat dissipation
means. Namely, drain water yielded in the refrigerating cycle is supplied to a surface
of the compressor using the drain-water supply unit to thereby dissipate the heat
of the compressor.
[0087] Embodiments of the present invention are explained below in detail.
<Embodiment 1>
[0088] Embodiment 1 of the present invention is explained first. FIG. 3A to FIG. 3C respectively
are a top plan view, a front view, and a side view of a heat exchange unit according
to this embodiment. As FIG. 3A to FIG. 3C show, the heat exchange unit 1 includes
a housing 10 constituted of steel sheet, etc. and, accommodated therein, a compressor
11, a heat exchanger 12, an accumulator 15, and a blower 21. The heat exchange unit
1 shown in FIG. 3A to FIG. 3C is an example, and the heat exchange unit 1 may include
the expansion valve 13 and selector valve 16 shown in FIG. 1 and FIG. 2. In FIG. 3A
to FIG. 3C, a part of the housing 10 is removed in order to show the state of the
inside of the heat exchange unit 1.
[0089] As FIG. 3A shows, the heat exchanger 12 has the shape of the letter L in terms of
plan view shape, and is provided along the back face 10_1 and a side face 10_2 of
the housing 10. As FIG. 3B shows, the blower 21 is fixed to the top face 10_5 and
bottom face 10_6 of the housing 10 with a fixing member 22. As FIG. 3A shows, the
blower 21 is driven by a motor 23. The back face 10_1 and front face 10_3 of the housing
10 have vent holes and the rotation of the blower 21 results in a wind blowing in
the direction indicated by the arrows (broken lines) in FIG. 3A. Thus, an air flow
flowing along the surface of the heat exchanger 12 can be increased, and heat exchange
in the heat exchanger 12 can be enhanced.
[0090] As FIG. 3A shows, the heat exchanger 12 and the blower 21 are provided in a space
31 surrounded by the back face 10_1, side face 10_2, and front face 10_3 of the housing
10 and by a partition 25. Meanwhile, the compressor 11 and the accumulator 15 are
provided in a space 32 surrounded by the back face 10_1, side face 10_4, and front
face 10_3 of the housing 10 and by the partition 25. Although a pipeline 18 on the
outlet side of the compressor 11 and a pipeline on the inlet side of the accumulator
15 are not shown in the drawings in this description, these pipelines are connected
to the selector valve 16 shown in FIG. 1 and FIG. 2.
[0091] In the heat exchange unit 1 according to this embodiment, the partition 25 has a
vent hole 27 formed therein at a position corresponding to the compressor 11, as shown
in FIG. 3C. In other words, the vent hole 27 is formed in a position where the compressor
11 and the partition 25 overlap each other when the heat exchange unit 1 is viewed
from a side. In FIG. 3A and FIG. 3B, the position where the vent hole 27 is formed
is indicated by a broken line. In FIG. 3C, the compressor 11 and the accumulator 15
are indicated by broken lines in order to clearly shown the position of the vent hole
27. By thus forming vent hole 27 in the partition 25, an air flow flowing around the
compressor 11 can be increased and cooling of the compressor 11 can be enhanced. Specifically,
a wind can blow from the space 31 where the blower 21 is provided (see FIG. 3A) to
the space 32 where the compressor 11 is provided, and cooling of the compressor 11
can be enhanced.
[0092] Although FIG. 3C shows an example in which a plurality of vent holes 27 are formed
in the partition 25, the shape of the vent holes in the heat exchange unit 1 according
to this embodiment is not limited to the shape in the example. For example, a vent
hole 28 having a size corresponding to the compressor 11 may be formed in the partition
25 as shown in FIG. 4. In this case also, the vent hole 28 is formed at a position
in the partition 25 which corresponds to the compressor 11, that is, in a position
where the compressor 11 and the partition 25 overlap each other when the heat exchange
unit 1 is viewed from a side.
[0093] As stated hereinabove, there have been cases where HFO-1123 in a high-temperature
high-pressure state, upon reception of energy, undergoes an exothermic chemical reaction
called a disproportionation reaction (self-decomposition reaction), which occurs like
a chain reaction. For refrigerating cycle apparatus employing working media including
HFO-1123, it has hence been necessary to inhibit the occurrence of such a disproportionation
reaction. Such a disproportionation reaction is prone to occur especially in the compressor
11, in which the working medium has a high temperature and a high pressure.
[0094] In the heat exchange unit 1 according to this embodiment, the partition 25 hence
has a vent hole 27 formed therein at a position corresponding to the compressor 11
as shown in FIG. 3C. By thus forming a vent hole 27 in the partition 25, an air flow
around the compressor 11 can be increased and cooling of the compressor 11 can be
enhanced. Consequently, the HFO-1123 can be inhibited from undergoing a disproportionation
reaction.
<Embodiment 2>
[0095] Embodiment 2 of the present invention is explained next.
[0096] FIG. 5 is a top plan view showing a heat exchange unit 2 according to embodiment
2. Constituent elements in FIG. 5 which are the same as in embodiment 1 are designated
by the same numerals to avoid duplication of explanation.
[0097] As FIG. 5 shows, the heat exchange unit 2 according to this embodiment includes an
air deflector 35 that directs a part of the air flow sent from the blower 21 toward
the compressor 11. The air deflector 35 can be formed using, for example, a steel
material or a resin material. The air deflector 35 may have a height corresponding
to the compressor 11 and, in this case, is fixed to the bottom face 10_6 of the housing
10 (see FIG. 3B). The air deflector 35 may be formed so as to extend from the bottom
face to the top face of the housing 10. In this case, the air deflector 35 can be
fixed to the top face 10_5 and the bottom face 10_6 of the housing 10 (see FIG. 3).
[0098] The air deflector 35 may be configured to be rotatable on an axis extending along
the vertical direction of the housing 10. Thus, the direction of the air flow deflected
by the air deflector 35 can be regulated and the wind direction can be more reliably
directed toward the compressor 11.
[0099] Since the heat exchange unit 2 according to this embodiment includes the air deflector
35, an air flow around the compressor 11 can be increased. Consequently, cooling of
the compressor 11 can be enhanced more than in the heat exchange unit 1 according
to embodiment 1 and the HFO-1123 can be more effectively inhibited from undergoing
a disproportionation reaction.
<Embodiment 3>
[0100] Embodiment 3 of the present invention is explained next.
[0101] FIG. 6 is a front view showing a heat exchange unit 3 according to embodiment 3.
FIG. 7A and FIG. 7B are top plan views for explaining operations of the heat exchange
unit 3 according to embodiment 3. As FIG. 6 and FIGs. 7A and 7B show, the heat exchange
unit 3 according to this embodiment differs from the heat exchange unit 1 according
to embodiment 1 in that the heat exchange unit 3 includes a wind direction changing
part 41 that changes the direction of wind of the blower 21 toward the compressor
11. Except for this, the heat exchange unit 3 has the same configuration as the heat
exchange unit 1 explained as embodiment 1. Hence, the same constituent elements are
designated by the same numerals to avoid duplication of explanation.
[0102] As FIG. 6 and FIGs. 7A and 7B show, the heat exchange unit 3 according to this embodiment
includes the wind direction changing part 41, a detecting part 42, a determination
part 43, and a control part 44. The wind direction changing part 41 is configured
to be capable of changing the direction of wind of the blower 21 toward the compressor
11. Specifically, as shown in FIG. 7A and FIG. 7B, the wind direction changing part
41 changes the direction of the blower 21 by rotating the blower 21 on a rotation
axis 48 extending along the vertical direction of the heat exchange unit 3. FIG. 7A
shows the state in which the direction of the wind from the blower 21 is normal, while
FIG. 7B shows the state in which the blower 21 faces toward the compressor 11.
[0103] The detecting part 42 detects the temperature of the working medium discharged from
the compressor 11, specifically, the temperature of the working medium within the
pipeline 18 on the outlet side of the compressor 11. The determination part 43 determines
whether or not the temperature of the working medium detected by the detecting part
42 is higher than a predetermined temperature. The control part 44 controls the wind
direction changing part 41 in accordance with a determination made by the determination
part 43. Specifically, in the case where the temperature of the working medium is
higher than the predetermined temperature, the control part 44 controls the wind direction
changing part 41 so that the direction of wind from the blower 21 is directed toward
the compressor 11, as shown in FIG. 7B.
[0104] The predetermined temperature, on the basis of which the determination part 43 makes
a determination, is set at a temperature lower than the temperature at which the HFO-1123
included in the working medium undergoes a disproportionation reaction. That is, since
the working medium is prone to undergo a disproportionation reaction at higher temperatures,
the direction of wind from the blower 21 is directed toward the compressor 11 to enhance
cooling of the compressor 11 before the working medium undergoes the disproportionation
reaction. Thus, the disproportionation reaction can be inhibited from occurring in
the compressor 11. The disproportionation reaction can be more reliably inhibited
by setting the predetermined temperature at a relatively low temperature.
<Embodiment 4>
[0105] Embodiment 4 according to the present invention is explained next.
[0106] FIG. 8 is a top plan view showing a heat exchange unit 4 according to embodiment
4. Constituent elements in FIG. 8 which are the same as in embodiment 1 are designated
by the same numerals to avoid duplication of explanation.
[0107] As FIG. 8 shows, in the heat exchange unit 4 according to this embodiment, a heat
sink 51 that dissipates the heat generated in the compressor 11 is provided to the
compressor 11. FIG. 8 shows the case where the heat sink 51 is provided to a part
of the periphery of the compressor 11. However, the heat sink 51 may be provided to
the whole periphery of the compressor 11. In the embodiment shown in FIG. 8, the heat
sink 51 is formed in a portion of the periphery of the compressor 11 which faces the
vent hole 27 formed in the partition 25. By thus forming a heat sink 51 on a portion
of the periphery of the compressor 11 which faces the vent hole 27 formed in the partition
25, the compressor 11 can be effectively cooled. As a material for constituting the
heat sink 51, use can be made of a material having a high thermal conductivity, such
as a metallic material.
[0108] Since the heat exchange unit 4 according to this embodiment includes the heat sink
51, cooling of the compressor 11 can be enhanced and the HFO-1123 can be more effectively
inhibited from undergoing a disproportionation reaction.
[0109] This embodiment may be combined with embodiment 2. Namely, the air deflector 35 shown
in FIG. 5 may be provided in the heat exchange unit 4 shown in FIG. 8. This configuration
can more effectively cool the compressor 11. This embodiment may also be combined
with embodiment 3. Namely, the wind direction changing part 41, detecting part 42,
determination part 43, and control part 44 shown in FIG. 6 and FIGs 7A and 7B may
be provided to the heat exchange unit 4 shown in FIG. 8. This configuration can more
effectively cool the compressor 11.
[0110] The invention according to this embodiment may be used alone without being combined
with any of the other embodiments. Namely, the heat exchange unit shown in FIG. 8
may be configured so that the partition 25 has no vent hole 27. In this case, the
heat of the compressor 11 can be dissipated via the heat sink 51 without necessitating
disposition of vent hole in the partition 25.
<Embodiment 5>
[0111] Embodiment 5 according to the present invention is explained next.
[0112] FIG. 9 is a side view showing a heat exchange unit 5 according to embodiment 5. The
heat exchange unit 5 according to this embodiment differs from the heat exchange unit
1 according to embodiment 1 in that drain water yielded in the refrigerating cycle
is used to cool the compressor 11. Except for this, the heat exchange unit 5 has the
same configuration as the heat exchange unit 1 explained as embodiment 1. Hence, the
same constituent elements are designated by the same numerals to avoid duplication
of explanation.
[0113] As FIG. 9 shows, the heat exchange unit 5 according to this embodiment includes
a pipeline 61, a drain-water reservoir 62, a pipeline 63, and an electromagnetic valve
64, which configure a drain-water supply unit.
[0114] The drain-water reservoir 62 reserves therein drain water yielded in the refrigerating
cycle. For example, drain water is yielded on the heat exchanger 14 of the refrigerating
cycle apparatus 100 shown in FIG. 1. The drain water yielded in the refrigerating
cycle is supplied to the drain-water reservoir 62 via the pipeline 61. The drain water
reserved in the drain-water reservoir 62 is supplied to a surface of the compressor
11 via the pipeline 63. The supply of the drain water to the surface of the compressor
11 from the drain-water reservoir 62 can be switched using the electromagnetic valve
64. By thus supplying the drain water to the surface of the compressor 11, the compressor
11 can be cooled.
[0115] As FIG. 9 shows, the drain-water supply unit of the heat exchange unit 5 according
to this embodiment further includes a detecting part 66, a determination part 67,
and a control part 68. The detecting part 66 detects the temperature of the working
medium discharged from the compressor 11, specifically, the temperature of the working
medium within the pipeline 18 on the outlet side of the compressor 11. The determination
part 67 determines whether or not the temperature of the working medium detected by
the detecting part 66 is higher than a predetermined temperature. The control part
68 controls the electromagnetic valve 64 in accordance with a determination made by
the determination part 67. Specifically, in the case where the temperature of the
working medium is higher than the predetermined temperature, the control part 68 opens
the electromagnetic valve 64 to supply drain water from the drain-water reservoir
62 to a surface of the compressor 11 and thereby cool the compressor 11.
[0116] The predetermined temperature, on the basis of which the determination part 67 makes
a determination, is set at a temperature lower than the temperature at which the HFO-1123
included in the working medium undergoes a disproportionation reaction. That is, since
the working medium is prone to undergo a disproportionation reaction at higher temperatures,
the electromagnetic valve 64 is opened to supply the drain water to a surface of the
compressor 11 and cool the compressor 11 before the working medium undergoes the disproportionation
reaction. Thus, the disproportionation reaction can be inhibited from occurring in
the compressor 11. The disproportionation reaction can be more reliably inhibited
by setting the predetermined temperature at a relatively low temperature.
[0117] The pipeline 63 that supply the drain water to the surface of the compressor 11 preferably
has such a shape that the drain water is evenly supplied to the surface of the compressor
11. For example, by attaching a shower head to the end of the pipeline 63, the drain
water can be evenly supplied to the surface of the compressor 11. The pipeline 63
may be configured so that the drain water is preferentially supplied to that portion
of the surfaces of the compressor 11 which faces the vent hole 27 formed in the partition
25 (see FIG. 3A). By thus supplying the drain water preferentially to the portion
of the compressor 11 which receives the wind, the vaporization of the drain water
is accelerated and cooling of the compressor 11 can be enhanced.
[0118] This embodiment may be combined with embodiment 2. Namely, the air deflector 35 shown
in FIG. 5 may be provided in the heat exchange unit 5 shown in FIG. 9. This configuration
can more effectively cool the compressor 11. This embodiment may also be combined
with embodiment 3. Namely, the wind direction changing part 41, detecting part 42,
determination part 43, and control part 44 shown in FIG. 6 and FIGs 7A and 7B may
be provided to the heat exchange unit 5 shown in FIG. 9. This configuration can more
effectively cool the compressor 11. In this case, the detecting parts 42 and 66 can
be integrated, the determination parts 43 and 67 can be integrated, and the control
parts 44 and 68 can be integrated. Furthermore, this embodiment may be combined with
embodiment 4. Namely, the heat sink 51 shown in FIG. 8 may be provided to the compressor
11 shown in FIG. 9. This configuration can more effectively cool the compressor 11.
[0119] The invention according to this embodiment may be used alone without being combined
with any of the other embodiments. Namely, the heat exchange unit shown in FIG. 9
may be configured so that the partition 25 has no vent hole. In this case, the heat
of the compressor 11 can be dissipated using drain water without necessitating disposition
of vent holes in the partition 25.
[0120] While the invention has been described in detail and with reference to specific
embodiments thereof, it will be apparent to one skilled in the art that various changes
and modifications can be made therein without departing from the spirit and scope
thereof. This application is based on a Japanese patent application filed on February
22, 2016 (Application No.
2016-030562), the contents thereof being incorporated herein by reference.
Description of Reference Numerals
[0121]
1, 2, 3, 4, 5 Heat exchange unit
10 Housing
11 Compressor
12 Heat exchanger
13 Expansion valve
14 Heat exchanger
15 Accumulator
16 Selector valve
17, 21 Blower
22 Fixing member
23 Motor
25 Partition
27, 28 Vent hole(s)
35 Air deflector
41 Wind direction changing part
42, 66 Detecting part
43, 67 Determination part
44, 68 Control part
51 Heat sink
62 Drain-water reservoir
64 Electromagnetic valve