TECHNICAL FIELD
[0001] The present invention relates to a refrigeration facility, which includes a refrigeration
device cooling an interior of a storage chamber, and more specifically to a technique
for lowering the risk of corrosion of components installed in the interior of the
storage chamber.
BACKGROUND
[0002] Refrigeration containers used in, e.g., marine transportation are known in the art
as refrigeration facilities provided with a refrigeration device for cooling an interior
of a container. Such refrigeration containers include a container refrigeration device
cooling the interior of a container body. Refrigeration storages and cold storages
are also known in the art as a refrigeration facilities cooling an interior of a container.
[0003] Patent Document 1 discloses a container refrigeration device. This container refrigeration
device is installed at a front opening of a container. The container refrigeration
device includes a frame, at a lower side of which an outside storage space facing
an exterior of the container is formed. A compressor, a condenser, an exterior fan,
and other components are installed in this outside storage space. Moreover, an inside
storage space facing an interior of the container is formed at an upper side of the
frame. An evaporator and an interior fan are installed in this inside storage space.
In this container refrigeration device, the compressor, the condenser and the evaporator
are connected by a refrigerant pipe thus forming a refrigerant circuit. A refrigerating
cycle is operated as a refrigerant is circulated through this refrigerant circuit,
and air inside the container is cooled by the evaporator.
CITATION LIST
PATENT DOCUMENTS
[0004] PATENT DOCUMENT 1: Japanese Unexamined Patent Publication No.
2004-325022
SUMMARY OF THE INVENTION
TECHNICAL PROBLEM
[0005] In a refrigeration container loaded with plants such as grapes, fumigation is applied
to sterilize an interior of the container. However, cases have occurred where components
installed inside the container have suffered from corrosion due to fumigants released
during fumigation, as well as due to gases (e.g., SO
2) emerging from disinfectant wipes. Corrosion may occur on components made of copper
(pipes, temperature thermistors etc.), aluminum (fan blades, plate members etc.),
or stainless steel.
[0006] Components suffering from corrosion need to be repaired or exchanged. Moreover, while
the corrosion of components can be detected after the fact, it is difficult to estimate
in advance whether corrosion is imminent. A procedure is conceivable where, for example,
a worker surveys whether air inside the container contains SO
2 and, based on results of this survey, estimates the possibility of corrosion. This,
however, is no realistic procedure. The corrosion of components is a problem occurring
not only in refrigeration containers. It may also occur in refrigeration facilities
such as refrigeration storages and cold storages.
[0007] In view of the foregoing background, the present invention attempts to provide a
technique for easily surveying corrosion of components installed inside a refrigeration
facility.
SOLUTION TO THE PROBLEM
[0008] A first aspect of the present disclosure relates to a refrigeration facility including
a refrigeration device (10), which cools an interior of a storage chamber and has
an evaporator (24) allowing air inside the container to pass through, the refrigeration
facility including: a condensate treatment unit (40) including a condensate collection
unit (41) collecting condensate water generated by the evaporator (24) and a condensate
disposal unit (42) disposing condensate water from the condensate collection unit
(41); and a corrosive gas detector (50) installed in the condensate treatment unit
(40) to detect corrosive gas in air inside the container based on properties of the
condensate water.
[0009] In the first aspect, by using the corrosive gas detector (50) to examine the properties
of the condensate water, it may be detected whether corrosion of components installed
inside the container is imminent.
[0010] In a second aspect, which is an embodiment of the first aspect, the corrosive gas
detector (50) may be installed in the condensate disposal unit (42).
[0011] In the second aspect, the corrosive gas detector (50) is installed in the condensate
disposal unit (42). The corrosive gas detector (50) may as well be installed in the
condensate collection unit (41). Since, however, the condensate disposal unit (42)
may be installed at an arbitrary spot in the refrigeration facility, in the second
aspect corrosive gas detection may be performed easily at an arbitrary location.
[0012] In a third aspect of the present disclosure, which is an embodiment of the second
aspect, the refrigeration device (10) may be a container refrigeration device (10)
including a casing (12) mounted to a container (11), the condensate disposal unit
(42) may be a drain hose (42) connected to the condensate collection unit (41), the
drain hose (42) may have a part at a condensate disposal side located in an external
storage space (S1), which is formed in the casing (12) so as to house refrigerant
circuit components of the refrigeration device (10), and the corrosive gas detector
(50) may be installed in the drain hose (42) at a location inside the external storage
space (S1).
[0013] According to the third aspect, in the container refrigeration device (10), corrosive
gas inside the container may be detected by using the corrosive gas detector (50)
installed in the drain hose (42) provided in the exterior storage space (S1), which
is easy to access for maintenance.
[0014] In a fourth aspect of the present disclosure, which is an embodiment of the third
aspect, a condensate trap (44) may be formed in the drain hose (42) at a location
inside the external storage space (S1), and the corrosive gas detector (50) may be
installed in the condensate trap (44) of the drain hose (42).
[0015] In the fourth aspect, the condensate trap (44) is installed in the drain hose (42).
As condensate accumulates in the condensate trap (44), corrosive gas detection may
be performed easily based on the properties of the accumulated condensate water.
[0016] In a fifth aspect of the present disclosure, which is an embodiment of the fourth
aspect, the condensate trap (44) may include a first U-turn (44a) curving downward
and a second U-turn (44b) curving upward, which are formed in the run of the drain
hose (42) and connected from upstream to downstream, and the corrosive gas detector
(50) may be installed in the second U-turn portion (44b) and located above a level
of condensate water accumulated in the first U-turn (44a) when the condensate water
flows through the second U-turn (44b).
[0017] In the fifth aspect, condensate water accumulates in the first U-turn (44a) of the
condensate trap (44). Installed above the level of the accumulated condensate water
when the condensate water flows out of the second U-turn (44b), the corrosive gas
detector (50) may perform corrosive gas detection based on the water properties gained
from information regarding the condensate water. Moreover, accumulating in the first
U-turn (44a), the condensate water seals off an end of the drain hose (42) inside
the container from an end of the drain hose (42) at a disposal side. When the refrigeration
device is operated and the container is cooled inside, pressure inside the container
lowers and air tends to enter from the condensate disposal side. As a countermeasure,
condensate water accumulated in the first U-turn (44a) serves as a seal and keeps
air from entering the container.
[0018] In a sixth aspect of the present disclosure, which is an embodiment of any one of
the first to fifth aspects, the corrosive gas detector (50) may be a condensate port
(43) including a portable pH sensor (45), which measures a pH value as a property
of the condensate water.
[0019] In the sixth aspect, installing the portable pH sensor (45) in the condensate port
(43), which is provided for a refrigeration facility such as a refrigeration container
or a refrigeration storage, allows for detecting corrosive gas inside the container.
[0020] In a seventh aspect of the present disclosure, which is an embodiment of any one
of the first to fifth aspects, the corrosive gas detector (50) may include a stationary
pH sensor (47) measuring the pH value as the property of the condensate water, and
the refrigeration facility may further include a measurement result display (48) connected
to the pH sensor and displaying measurement results provided by the sensor.
[0021] In the seventh aspect, the pH sensor (47) is permanently installed in a refrigeration
facility such as a refrigeration container or a refrigeration storage and detects
corrosive gas inside the refrigeration facility. Measurement results provided by the
pH sensor (47) are displayed on the measurement result display (48).
ADVANTAGES OF THE INVENTION
[0022] According to the first aspect of the present disclosure, by using the corrosive gas
detector (50) to examine properties of the condensate water, it may be easily determined
whether corrosion of the components installed inside the container is imminent. Thus,
an imminent corrosion of the components inside the container may be delayed by cleaning
the interior of the container. Further, in the first aspect of the present disclosure,
simply installing the corrosive gas detector (50) in the condensate treatment unit
(40) may reduce the risk of failures of the refrigeration device and may cut costs
to a minimum.
[0023] According to the second aspect of the present disclosure, the corrosive gas detector
(50) is installed in the condensate disposal unit (42), the installation location
of which may be chosen relatively freely within the refrigeration device. Therefore,
corrosive gas detection for the interior of the container may be performed even outside
the container, which improves efficiency in performing the detection procedure.
[0024] According to the third aspect of the present disclosure, disposing the drain hose
(42) in the external storage space (S1) of the container refrigeration device (10)
and installing the corrosive gas detector (50) in the drain hose (42) allows for performing
corrosive gas detection for the interior of the container (11) in the external storage
space (S1), which is easy to access for maintenance.
[0025] According to the fourth aspect of the present disclosure, installing the condensate
trap (44) in the drain hose (42) and having the condensate water accumulate in the
condensate trap (44) may allow for easily performing corrosive gas detection based
on the properties of the accumulated condensate water as well as for maintaining an
uncomplicated configuration.
[0026] According to the fifth aspect of the present disclosure, the corrosive gas detector
(50) is installed above the level of the condensate water accumulated in the first
U-turn (44a) of the condensate trap (44) when the condensate water flows out of the
second U-turn (44b). Thus, using this corrosive gas detector (50) may allow for easily
and accurately performing corrosive gas detection based on the properties of the condensate
water gained from information regarding the condensate water level. Moreover, since
it is superfluous to provide a sealant for preventing water leakage from the condensate
port (43), an uncomplicated configuration may be maintained.
[0027] According to the sixth aspect of the present disclosure, installing the condensate
port (43) in a refrigeration facility such as a refrigeration container or a refrigeration
storage allows for easily detecting corrosive gas in an interior of the refrigeration
facility by using the portable pH sensor (45).
[0028] According to the seventh aspect of the present disclosure, the pH sensor (45) is
permanently installed in a refrigeration facility such as a refrigeration container
or a refrigeration storage, and measurement results provided by the pH sensor (47)
are displayed on the measurement result display (46). Thus, if a concentration of
corrosion gas in the interior of the refrigeration facility is high, an alarm signal
may be given out to prompt cleaning of the interior of the refrigeration facility.
Further, by re-performing the corrosion gas detection after the cleaning, it may be
determined whether the interior of the refrigeration facility is clean.
BRIEF DESCRIPTION OF THE DRAWINGS
[0029]
[FIG. 1] FIG. 1 is a perspective view of a container refrigeration device according
to an embodiment of the present invention when viewed from outside the container.
[FIG. 2] FIG. 2 is a cross-sectional side view illustrating a configuration of the
container refrigeration device according to the embodiment.
[FIG. 3] FIG. 3 is a piping system diagram illustrating a configuration of a refrigerant
circuit of the embodiment.
[FIG. 4] FIG. 4 is a front view of the container refrigeration device having an electrical
component box removed.
[FIG. 5] FIG. 5 is a perspective view of the container refrigeration device having
the electrical component box, a condenser and a gas mixture supply device removed.
[FIG. 6] FIG. 6 is a side view showing a part of a drain hose at a condensate disposal
side.
[FIG. 7] FIG. 7 is a back view of the container refrigeration device.
[FIG. 8] FIG. 8 is a partial cross-sectional view of the container refrigeration device.
[FIG. 9] FIG. 9 is a side view illustrating a part of the condensate disposal side
according to a variation of the embodiment.
[FIG. 10] FIG. 10 is a side view illustrating a part of the drain hose at a condensate
disposal side according to another variation of the embodiment.
DESCRIPTION OF EMBODIMENTS
[0030] Embodiments of the present invention will be described in detail with reference to
the drawings. In the following embodiments, the present invention has been applied
to a container (refrigeration container) serving as an example refrigeration device.
Note that the beneficial embodiments explained below are mere examples in nature,
and are not intended to limit the scope, applications, and use of the present invention.
[0031] As shown in FIGS. 1 and 2, a container refrigeration device (10) is designed to cool
or to refrigerate an interior of a container (11) used in, e.g., marine transportation.
The container refrigeration device (10) includes a refrigerant circuit (20) employing
a refrigerating cycle to cool air in the container (11) (see FIG. 3). The interior
of a container (11) is loaded with plants (15) packed in boxes, such as grapes.
[0032] The container (11) has the shape of a box with an open end. A casing (12) is attached
to close this one open end. The casing (12) includes an exterior wall (12a) located
outside the container (11) and an interior wall (12b) located inside the container
(11). The exterior and interior walls (12a) and (12b) may be made of, for example,
aluminum alloy.
[0033] The exterior wall (12a) is attached to a periphery of the opening of the container
(11) so as to close the open end of the container (11). The exterior wall (12a) is
formed such that a lower part of the exterior wall (12a) protrudes into the container
(11).
[0034] The interior wall (12b) faces the exterior wall (12a). The interior wall (12b) fits
the lower part of the exterior wall (12a), and protrudes into the container. A thermal
insulator (12c) is provided in a space between the interior and exterior walls (12b)
and (12a).
[0035] A lower part of the casing (12) is formed so as to protrude into the container (11).
In this way, an external storage space (S1) is formed outside the container (11) in
the lower part of the casing (12), and an internal storage space (S2) is formed inside
the container (11) in an upper part of the casing (12).
[0036] The casing (12) has two access doors (16), which are arranged side by side in a width
direction and can be opened and closed during maintenance. An electrical component
box (17) adjacent to an external fan (25), which will be described later, is located
in the external storage space (S1) of the casing (12).
[0037] A partition plate (18) is located inside the container (11). This partition plate
(18) is a substantially rectangular plate member, and stands upright against a face
of the casing (12) inside the container (11). This partition plate (18) separates
the internal storage space (S2) from the interior of the container (11).
[0038] A suction port (18a) is formed between an upper end of the partition plate (18) and
a ceiling surface of the container (11). Air inside the container (11) is taken through
the suction port (18a) into the internal storage space (S2).
[0039] A floorboard (19) is provided inside the container (11), leaving a gap between the
floorboard (19) and a bottom surface of the container (11). The boxed plants (15)
are placed on the floorboard (19). An air passage (19a) is formed between the floorboard
(19) and the bottom surface of the container (11). A gap is left between a lower end
of the partition plate (18) and the bottom surface of the container (11) and communicates
with the air passage (19a).
[0040] A blowout port (18b) is provided at a front side of the container (11) at the floorboard
(19) (on the right in FIG. 2) for blowing air treated by the container refrigeration
device (10) (i.e., cooled air inside the container) into the container (11).
[0041] As shown in FIG. 3, the container refrigeration device (10) includes a refrigerant
circuit (20) in which a vapor compression refrigeration cycle is operated as a refrigerant
is circulated. The refrigerant circuit (20) includes a compressor (21), a condenser
(22), an expansion valve (23), and an evaporator (24), which are connected by a refrigerant
pipe (28) in this order.
[0042] As shown in FIGS. 1 and 2, the compressor (21) and the condenser (external heat exchanger)
(22) are housed in the external storage space (S1). The external fan (25) is located
above the condenser (22). The external fan (25) is driven in rotation by an external
fan motor (25a), guides air outside the container (11) into the external storage space
(S1), and sends the air to the condenser (22). In the condenser (22), heat is exchanged
between a refrigerant flowing through the condenser (22) and the outside air.
[0043] The evaporator (24) is housed in the internal storage space (S2). Two internal fans
(26) are located above the evaporator (24) in the internal storage space (S2) and
arranged side by side in the width direction of the casing (12).
[0044] The internal fans (26) are driven in rotation by internal fan motors (26a), and guide
the air inside the container (11) through the suction port (18a) to send the air into
the evaporator (24). In the evaporator (24), heat is exchanged between a refrigerant
flowing through the evaporator (24) and the air inside the container. The air inside
the container is cooled when passing through the evaporator (24) as heat is dissipated
by the refrigerant, and is then blown via the air passage (19a) from the blowout port
(18b) into the container (11).
[0045] The container refrigeration device (10) includes a gas mixture supply device (30)
for regulating oxygen concentration inside the container by supplying a gas mixture,
which has a low oxygen concentration, into the container (11). The gas mixture supply
device (30) is a unit located in a lower left corner of the external storage space
(S1) as shown in FIG. 1. An inverter box (29) housing a drive circuit for driving
the compressor (21) at a variable velocity is located to the right of the gas mixture
supply device (30).
[0046] FIG. 4 is a front view of the container refrigeration device (10) having the electrical
component box (17) removed. FIG. 5 is a perspective view of the container refrigeration
device (10) having the electrical component box (17), the condenser (22), and a gas
mixture supply device (30) removed. FIG. 6 is a side view showing a part of a condensate
disposal side of the drain hose (42). Further, FIG. 7 is a back view of the container
refrigeration device (10), and FIG. 8 is a partial cross-sectional view of the container
refrigeration device (10).
[0047] As shown in FIG. 7, according to this embodiment, a drain pan (condensate collection
unit) (41) collecting condensate water generated by the evaporator (24) is provided
at a bottom of the internal storage space (S2). This drain pan (41) has an inclined
face which becomes lower from both ends toward a center of the casing (12). The drain
hose (condensate disposal unit) (42), which disposes condensate water from the drain
pan (41), is connected to a center of the drain pan (41) and extends into the external
storage space (S1). The drain pan (41) and the drain hose (42) form the condensate
treatment unit (40).
[0048] The drain hose (42) has a part at the condensate disposal side located in the external
storage space (S1), which is formed in the casing (12) so as to house components of
the refrigerant circuit (20). The drain hose (42) includes the condensate port (43),
which is located inside the external storage space (S1). Specifically, the condensate
trap (44) is formed in the drain hose (42) inside the external storage space (S1),
and the condensate port (43) is installed in the condensate trap (44) of the drain
hose (42).
[0049] As schematically shown in FIG. 9, the condensate port (43) may include a portable
corrosive gas sensor (45) detecting corrosive gas in the air inside the container
based on properties of the condensate water. Such a condensate port (43) is a port
detecting corrosive gas in the air inside the container based on the properties of
the condensate water, and forms the corrosive gas detector (50) of the present invention.
More precisely, a portable pH sensor measuring a hydrogen ion exponent (pH value)
of the condensate water may be employed as the portable corrosive gas sensor (45).
[0050] The condensate trap (44) specifically includes a first U-turn (44a) curving downward
and a second U-turn (44b) curving upward, which are formed in the run of the drain
hose (42) and connected from upstream to downstream. The condensate port (43), which
is the corrosive gas detector (50), is installed in the second U-turn portion (44b)
and located above a level of condensate water accumulated in the first U-turn (44a)
when the condensate water flows through the second U-turn (44b).
[0051] In the present embodiment, when the refrigeration device (11) is operated, water
drops condensed on the evaporator drop down into the drain pan (41) as indicated by
arrows in FIG. 7, and this condensate water flows toward the center of the drain pan
(41). Then, the condensate water flows through the drain hose (42) and is disposed
via the condensate trap (44) out of the device.
[0052] While detecting corrosive gas inside the container, the pH sensor (45) is installed
in the condensate port (43) and examines the properties (pH value) of the condensate
water. A low pH value detected by the pH sensor (45) signifies a high acidity and
it may be concluded that corrosion of components installed inside the container is
imminent since it may be assumed that acid gasses contained in the air inside the
container may be found dissolved in the condensate water. In the case where corrosion
inside the container is imminent, it is beneficial to clean the interior of the container.
A high pH value, however, signifies a low acidity, which may lead to the conclusion
that corrosion of components installed inside the container is not imminent.
-Advantages of Embodiment-
[0053] According to the present embodiment, the condensate port (43) is installed in the
drain hose (42) and serves as the corrosive gas detector (50). The pH sensor (45)
is installed in this condensate port (43) to measure the pH value of the condensate
water. In this way it may be determined whether the condensate water has a high acidity,
and thus it may be easily determined whether corrosion of the components installed
inside the container is imminent. If corrosion of the components installed inside
the container is imminent, it is beneficial to clean the interior of the container.
[0054] Moreover, in the present embodiment, the drain trap (44) is formed in the drain hose
(42), and the condensate port (43) is installed in the condensate trap (44). Thus,
as shown in FIG. 9, the pH sensor (45) may be securely introduced into the condensate
water. This may make corrosion gas detection more precise.
[0055] Further, in the present embodiment, the condensate port (43), which is the corrosive
gas detector (50), is installed above the level of the condensate water accumulated
in the first U-turn (44a) of the condensate trap (44) when the condensate water flows
out of the second U-turn (44b). Thus, the condensate port (43) above the level of
the condensate water may perform the corrosive gas detection easily and accurately
based on the properties of the condensate water accumulated in the first U-turn (44a)
of the condensate trap (44). Moreover, since it is superfluous to provide a sealant
for preventing water leakage from the condensate port (43), an uncomplicated configuration
may be maintained.
[0056] Furthermore, since in the present embodiment condensate water accumulates in the
first U-turn (44a), an end of the drain hose (42) inside the container and an end
of the drain hose (42) at a disposal side are sealed off by the condensate water.
Generally, when a refrigeration device is operated and an interior of a container
is cooled, pressure inside the container lowers and air tends to enter from a condensate
disposal side. As a countermeasure, in the above configuration, the condensate water
accumulated in the first U-turn (44a) serves as a seal and keeps air from entering
the container.
«Other Embodiments»
[0057] The above embodiment may have the following configurations.
[0058] Regarding the above embodiment, an example has been described where the present invention
is applied to the container (11) including the container refrigeration device (10)
cooling the interior of the container. However, the present invention is not limited
to the container (11). The present invention may be for example applied to a refrigeration
storage or a cold storage, given that the refrigeration storage or cold storage is
a refrigeration facility, which includes a refrigeration device cooling the interior
of the facility, and that this refrigeration device has an evaporator, which allows
air inside the facility to pass through.
[0059] Furthermore, regarding the present embodiment, an example has been described where
the properties of the condensate water are examined using the portable pH sensor (45),
and where corrosive gas inside the container is detected based on these properties.
As shown in FIG. 10, however, a stationary pH sensor (47) serving as the corrosive
gas detector (50) may be installed in the drain hose (42) instead. In this case, a
measurement result display (48), which is connected to the pH sensor (47) and displays
measurement results provided by the pH sensor (47), is installed in the container
refrigeration device (10) (see FIG. 1). FIG. 1 shows an example where the measurement
result display (48) is installed in the electrical component box (17). Installing
the measurement result display (46) allows for giving out a warning signal to prompt
cleaning of the interior of the container. Further, by re-performing the corrosion
gas detection after the cleaning, it may be determined whether the interior of the
container is clean.
[0060] Moreover, in the above embodiment, the corrosive gas detector (50) is installed in
the drain hose (42). However, as long as the corrosive gas detector (50) is installed
at a location in the condensate treatment unit (40) which is reached by the condensate
water, the corrosive gas detector (50) may as well be installed in the drain pan (41).
Also, in the case where the corrosive gas detector (50) is installed in the drain
hose (42), an installation location different from that in the above embodiment may
be chosen.
INDUSTRIAL APPLICABILITY
[0061] As can be seen from the foregoing, the present invention is useful for a technique
for lowering the risk of corrosion of components installed inside a refrigeration
facility, which includes a refrigeration device cooling an interior of the refrigeration
facility.
DESCRIPTION OF REFERENCE CHARACTERS
[0062]
- 10
- Container Refrigeration Device (Refrigeration Device)
- 11
- Container (Refrigeration Facility)
- 12
- Casing
- 24
- Evaporator
- 40
- Condensate Treatment Unit
- 41
- Drain Pan (Condensate Collection Unit)
- 42
- Drain Hose (Condensate Disposal Unit)
- 43
- Condensate Port (Corrosive Gas Detector)
- 44
- Condensate Trap
- 45
- pH Sensor
- 47
- pH Sensor
- 48
- Measurement Result Display
- 50
- Corrosive Gas Detector
- S1
- External Storage Space