Abstrict A temperature setting part sets a reference temperature of the
interior of a refrigerating compartment of a refrigerator. A door
opening/closing detection part detects opening and closing of a
door of the refrigerating compartment. First and second temperature
detecting parts detect the interior and exterior temperatures of
the refrigerating compartment respectively. An air curtain fan driving
part drives an air curtain fan. A control part performs a normal
cooling operation to control the interior temperature of the refrigerating
compartment by driving the cooling fan when the interior temperature
is under a reference temperature, drives the air curtain fan with
each of the numbers of rotations corresponding to each of several
temperature ranges, and performs the normal cooling operation by
stopping the driving of the air curtain fan if the closing of the
door of the refrigerating compartment is detected. Cooling efficiency
and electric power efficiency are enhanced by efficiently driving
the air curtain fan according to the interior and exterior conditions
of the refrigerating compartment.
Claims What is claimed is:
1. An air curtain fan driving device, comprising:
a temperature setting part for setting a reference temperature
of an interior of a refrigerating compartment of a refrigerator;
a door opening/closing detection part for detecting opening and
closing of a door of the refrigerating compartment;
first and second temperature detecting parts for detecting the
interior and exterior temperature of the refrigerating compartment,
respectively;
an air curtain fan driving part for driving an air curtain fan;
and
a control part for 1) performing a normal cooling operation to
control the interior temperature of the refrigerating compartment
by driving a cooling fan when the interior temperature is above
the reference temperature, 2) determining which of several temperature
ranges the exterior temperature belongs in, when the opening of
the door of the refrigerating compartment is detected by the door
opening/closing detection part, wherein the several temperature
ranges are preset, 3) driving the air curtain fan with each of a
number of rotations per minute corresponding to each of the several
temperature ranges according to a determination result during the
opening of the door, and 4) performing the normal cooling operation
by stopping the driving of the air curtain fan when the closing
of the door of the refrigerating compartment is detected.
2. An air curtain fan driving device as claimed in claim 1, wherein
the control part gives a weight to the number of rotations per minute
if when the cooling fan is driven, and enables the air curtain fan
to be driven with a weighted number of rotations per minute when
the door of the refrigerating compartment is opened during the driving
of the cooling fan.
3. An air curtain fan driving method, comprising the steps of:
a) performing a normal refrigerating operation for controlling
an interior temperature of a refrigerating compartment by setting
a reference temperature of a refrigerating compartment of a refrigerator
and by driving a cooling fan when the interior temperature is above
the reference temperature;
b) determining a number of rotations per minute of the air curtain
fan based on an exterior temperature of the refrigerating compartment
when a door of the refrigerating compartment is opened;
c) driving the air curtain fan with the number of rotations per
minute by step b) while the door is opened; and
d) performing the normal refrigerating operation by stopping the
air curtain fan when the door of the refrigerating compartment is
closed.
4. An air curtain fan driving method as claimed in claim 3, wherein
the step b) includes the steps of:
b-1) determining which of temperature ranges the exterior temperature
belongs in, wherein the temperature ranges are predetermined; and
b-2) selecting one among numbers of rotations per minutes according
to a determination result by step b-1), such that the number of
rotations per minute is determined, wherein the numbers of rotations
per minute are predetermined to correspond to the temperature ranges,
respectively.
5. An air curtain fan driving method, comprising the steps of:
a) performing a normal refrigerating operation for controlling
an interior temperature of a refrigerating compartment by setting
a reference temperature of a refrigerating compartment of a refrigerator
and by driving a cooling fan when the interior temperature is above
a reference temperature;
b) driving the air curtain fan with a number of rotations per minute
of the air curtain fan set according to several temperature ranges,
wherein the several temperature ranges result from the temperature
difference calculated based on the exterior temperature and the
interior temperature if the opening of the door of the refrigerating
compartment of the refrigerator is detected; and
c) performing the normal refrigerating operation by stopping the
air curtain fan if the closing of the refrigerating compartment
of the refrigerator is detected.
6. An air curtain fan driving method as claimed in claim 5, wherein
the temperature difference is the exterior temperature.
7. An air curtain fan driving method as claimed in claim 5, wherein
the temperature difference is the difference between the exterior
temperature and the interior temperature of the refrigerating compartment. Description BACKGROUND OF THE INVENTION
1. Field of the Invention
The present invention relates to a refrigerator, and more particularly
to an air curtain fan driving device and method for a refrigerator
for driving an air curtain fan according to interior and exterior
conditions of a refrigerator.
2. Description of the Prior Art
Viewing the refrigerant circulation cycle in a refrigerator, as
gas refrigerant with high-temperature and high-pressure caused by
a compressor passes through a condenser, the gas refrigerant transmits
its heat to the exterior and is converted into liquid refrigerant.
Thereafter, the liquid refrigerant, which still has high pressure,
passes through a dryer, so that foreign materials and water component
in the liquid refrigerant are removed, and the liquid refrigerant
without the foreign materials and water moves to the capillary tube.
The liquid refrigerant moving through the capillary tube expands
in a liquid/gas-mixed state to easily evaporate, thereby absorbing
ambient heat in order for the refrigerant to return to the original
refrigerant condition. Accordingly, the refrigerant is repeatedly
circulated as a cooling air supply in the refrigerator.
During operation of the refrigerator, the interior temperature
of the refrigerator may rise due to an overload in the refrigerating
compartment of the refrigerator and if exterior air flows in the
refrigerating compartment while the refrigerating compartment door
is opened. At this time, in order to return the interior temperature
of the refrigerating compartment to a normal state, an air curtain
fan has been mounted in the refrigerating compartment in recent
years.
A temperature control method for refrigerator is disclosed, in
U.S. Pat. No. 5,263,332 granted to Mr. Park on Nov. 23, 1993, for
reducing the cooling time by stabilizing the temperature fluctuation
occurring when the refrigerator door is opened. The patent includes
a step for controlling a compressor and a fan for a normal operation
in order to maintain interior temperature of a refrigerator at a
temperature preset by a user (called "normal operation step").
In a door-opening control step, if opening of a door of the refrigerator
is detected, the fan is turned off, and a time period during the
opening of a door of the refrigerator is calculated until closing
of the door is detected. Thereafter, if the closing of the door
is detected, a temperature-resetting step restarts the normal operation
step after automatically resetting the preset temperature based
on the calculated time period. A reset temperature operation step
determines whether the temperature is reset during the normal operation
step. If the temperature is reset, the compressor and the fan are
driven for a cooling operation until the temperature reaches reset
temperature. Thereafter, the reset temperature operation step restarts
the normal operation step. The patent of Mr. Park enhances food
preservation and the efficiency of the refrigerator since the interior
temperature influenced by exterior air when a door of the refrigerator
has been opened is rapidly stabilized after the closing of the door.
Hereinafter, a conventional air curtain fan driving device will
be described in detail with reference to FIG. 1. FIG. 1 is a view
for showing a conventional air curtain fan driving device. The conventional
air curtain fan driving device 10 includes an air curtain fan 100,
a temperature detector 102, a compressor 104, a compressor driver
106, a cooling fan 108, a cooling fan driver 110, an air curtain
fan driver 112, and a controller 114.
The temperature detector 102 detects an interior temperature T1
of the refrigerator under the control of the controller 114. The
detection of the interior temperature T1 of the refrigerator is
applied to the controller 114. The compressor 104 converts normal
gas refrigerant into gas refrigerant of high temperature and high
pressure. The compressor driver 106 controls the driving of the
compressor 104. The cooling fan 108 blows cool air into the refrigerating
compartment. The cooling air is provided from the evaporator (not
shown). The cooling fan driver 110 controls the driving of the cooling
fan 108. The controller 114 controls the operations of the temperature
102, compressor driver 106, cooling fan driver 110, and air curtain
fan driver 112. The controller 114 causes normal cooling operations
to be performed since the controller 114 drives the compressor
104 and cooling fan 108 by the compressor driver 106 and cooling
fan driver 110 respectively. The controller 114 determines whether
the interior temperature T1 of the refrigerating compartment detected
by the temperature detector 102 is normal.
Hereinafter, operations of the conventional air curtain fan driving
device will be described in detail.
FIG. 2 is a flow chart for explaining operations of the conventional
air curtain fan driving device of FIG. 1.
When electric power is applied, the controller 114 drives the compressor
104 and cooling fan 108 by means of the compressor driver 106 and
cooling fan driver 110 respectively, so that normal cooling operations
are performed (step S201). The temperature detector 102 detects
an interior temperature T1 of the refrigerator under the control
of the controller 114 (step S202). The detected interior temperature
T1 is transmitted to the controller 114. The controller 114 determines
whether the detected interior temperature T1 is a normal temperature
by the temperature detector 102 (step S203). If the detected interior
temperature T1 is below or over the normal temperature as a result
of the determination of the step S203, the compressor driver 106
drives the compressor 104 under the control of the controller 114
(step S204). Thereafter, the cooling fan driver 108 and the air
curtain fan driver 112 drive the cooling fan 108 and the air curtain
fan 100 under the control of the controller 114 respectively (step
S205). In step 206, the controller 114 determines again whether
the detected interior temperature T1 by the temperature detector
102 is the normal temperature. If the detected interior temperature
T1 is below or over the normal temperature as a result of the determination
of the step S206, the step S204 is restarted.
In the meantime, if the detected interior temperature T1 is determined
as the normal temperature, the controller 114 enables the normal
cooling operations to be performed (S207).
With the conventional method as mentioned above, if the temperature
of the refrigerating compartment is below the normal temperature,
the cooling efficiency is enhanced by driving the air curtain fan
as well as the cooling fan. However, by means of the conventional
method, if the refrigerator door is opened, the air curtain fan
is driven regardless of the interior or exterior temperature of
the refrigerating compartment. Accordingly, the air curtain fan
prevents the cool air from flowing out when the refrigerator door
is open, but electric power is excessively consumed.
SUMMARY OF THE INVENTION
It is an object of the present invention to provide an air curtain
fan driving device for a refrigerator capable of efficiently controlling
the driving of the air curtain fan in accordance with interior and
exterior conditions of the refrigerating compartment of a refrigerator.
It is another object of the present invention to provide an air
curtain fan driving method for a refrigerator capable of efficiently
controlling the driving of the air curtain fan in accordance with
interior and exterior conditions of the refrigerating compartment
of a refrigerator.
In order to achieve the above objects, an air curtain fan driving
device according to the present invention includes a temperature
setting part, a door opening/closing detection part, first and second
temperature detecting parts, an air curtain fan driving part, and
a control part. The temperature setting part sets a reference temperature
of an interior of a refrigerating compartment of a refrigerator.
The door opening/closing detection part detects the opening and
closing of a door of the refrigerating compartment. The first and
second temperature detecting parts detect the interior and exterior
temperatures of the refrigerating compartment respectively. The
air curtain fan driving part is for driving an air curtain fan.
The control part performs a normal cooling operation to control
the interior temperature of the refrigerating compartment by driving
the cooling fan when the interior temperature is under a reference
temperature, drives the air curtain fan with each of the numbers
of rotations corresponding to each of several temperature ranges,
and performs the normal cooling operation by stopping the driving
of the air curtain fan if the closing of the door of the refrigerating
compartment is detected. The temperature difference indicates the
exterior temperature. The temperature difference is the difference
between the interior temperature and the exterior temperature. The
control part of the air curtain fan driving device for the refrigerating
compartment sets a weighted value if the cooling fan is driven,
and enables the air curtain fan to be driven with a number of rotations
added by the weighted value to the number of rotations of the air
curtain fan if the door of the refrigerating compartment is opened
during the driving of the cooling fan.
In order to achieve the air curtain fan driving method, the method
comprises steps of a) performing a normal refrigerating operation
for controlling an interior temperature of a refrigerating compartment
by setting a reference temperature of a refrigerating compartment
of a refrigerator and by driving a cooling fan under the reference
temperature, b) driving the air curtain fan with the number of rotations
of the air curtain fan set according to several temperature ranges,
wherein the several temperature ranges result from the temperature
difference calculated based on the exterior temperature and the
interior temperature if the opening of the door of the refrigerating
compartment of the refrigerator is detected, and c) performing the
normal refrigerating operation by stopping the air curtain fan if
the closing of the refrigerating compartment of the refrigerator
is detected. In the steps, the temperature difference is the exterior
temperature. The temperature difference is the difference between
the exterior temperature and the interior temperature of the refrigerating
compartment of the refrigerator. Further, in an air curtain fan
driving method may comprise steps of a) performing a normal refrigerating
operation for controlling an interior temperature of a refrigerating
compartment by setting a reference temperature of a refrigerating
compartment of a refrigerator and by driving a cooling fan under
the reference temperature, b) driving the air curtain fan with the
number of rotations of the air curtain fan set according to several
temperature ranges, wherein the several temperature ranges result
from the temperature difference calculated based on the exterior
temperature and the interior temperature if the opening of the door
of the refrigerating compartment of the refrigerator is detected,
3) performing the normal refrigerating operation by stopping the
air curtain fan if the closing of the refrigerating compartment
of the refrigerator is detected. Here, the temperature difference
is the exterior temperature. The temperature difference is the difference
between the exterior temperature and the interior temperature of
the refrigerating compartment.
BRIEF DESCRIPTION OF THE DRAWINGS
These and other objects and features of the present invention can
be understood through the following embodiment by reference to the
accompanying drawing, in which:
FIG. 1 is a view for showing a conventional air curtain fan driving
device for a refrigerator;
FIG. 2 is a flow chart for explaining operations of the conventional
air curtain fan driving device of FIG. 1;
FIG. 3 is a block diagram for showing an air curtain fan driving
device for a refrigerator according to the first and second embodiments
of the present invention;
FIG. 4 is a flow chart for explaining operations of the air curtain
fan driving device for a refrigerator according to the first embodiment
of the present invention; and
FIG. 5 is a flow chart for explaining operations of the air curtain
fan driving device for a refrigerator according to the second embodiment
of the present invention.
DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS
Hereinafter, the air curtain fan driving device according to the
first and second embodiments of the present invention will be described
in detail with reference to the accompanying drawings.
The First Embodiment
The air curtain fan driving device for a refrigerator 30 according
to the first embodiment of the present invention is shown in FIG.
3.
The device 30 includes a temperature setting part 302, a door opening/closing
detection part 304, a first temperature detecting part 306, a second
temperature detecting part 308, a cooling fan driving part 310,
an air curtain fan driving part 312, a cooling fan 314, an air curtain
fan 316, and a control part 300.
The temperature setting part 302 enables a user to set a reference
temperature Tr for controlling the interior temperature T1 of the
refrigerating compartment. The door opening/closing detection part
304 detects whether the refrigerator door is opened or closed by
means of a switching circuit. The first temperature detecting part
306 measures the interior temperature T1 of the refrigerating compartment.
The second temperature detecting part 308 measures exterior temperature
T0 around the refrigerating compartment. The measured interior and
exterior temperatures T1 and T0 are applied to the control part
300. The cooling fan driving part 310 controls the driving of the
cooling fan 314. The air curtain fan driving part 310 controls the
driving of the air curtain fan 300. The control part 300 performs
normal cooling operations for maintaining the temperature of the
refrigerating compartment at the reference temperature Tr by operating
the cooling fan 314 in case that the interior temperature T1 of
the refrigerating compartment is higher than the reference temperature
Tr of the refrigerating compartment. The control part 300 sets a
weighted value M to "0" when the cooling fan is disenabled
during the normal cooling operation. Further, the control part 300
sets the weighted value M to "M0" when the cooling fan
is enabled. The control part 300 determines whether the cooling
fan 314 is driven in case that the opening of the door of the refrigerating
compartment is detected from the door opening/closing detection
part 304 during the normal cooling operations. The exterior temperature
T0 of the refrigerating compartment measured by means of the second
temperature detecting part 308 is classified into several temperature
ranges. If the cooling fan 314 is disenabled at the time the door
of the refrigerating compartment is opened, the air curtain fan
316 is enabled to be operated at a higher speed in a higher temperature
range. For example, the exterior temperature T0 is classified into
several temperature ranges such as T1(T0<20.degree. C.), T2(20.degree.
C..ltoreq.T0.gtoreq.30.degree. C.), and T3(30.degree. C..ltoreq.T0).
The air curtain fan is driven in several rotation numbers, which
will be denoted as reference numerals RPM1, RPM2, and RPM3, according
to the temperature ranges, so that the air curtain fan is driven
at a higher rotation number in a higher temperature range. The number
of rotations of the air curtain fan at the normal temperature is
denoted as a reference numeral RPM. If the door of the refrigerating
compartment is opened, a weighted value M, which is determined for
each of the temperature ranges, is added to each of the numbers
of rotations. That is, if the cooling fan 314 is driven, the air
curtain fan 316 is driven with the number of rotations added by
Mo to each of the numbers of rotations RPM1, RPM2, and RPM3 corresponding
to each of the temperature ranges. For example, the air curtain
fan 316 is driven at the number of rotations of RPM1', or RPM2',
or RPM3' at the exterior temperature classified into T1(T0<20.degree.
C.), or T2(20.degree. C..ltoreq.T0.ltoreq.30.degree. C.), or T3(30.degree.
C..ltoreq.T0), wherein RPM1'=RPM1+Mo, RPM2'=RPM2+Mo, and RPM3'=RPM3+Mo.
Hereinafter, the air curtain fan driving method according to the
first embodiment of the present invention will be described in detail
with reference to FIG. 4. FIG. 4 is a flow chart for explaining
the air curtain fan driving method for a refrigerator according
to the first embodiment of the present invention.
If a user sets a reference temperature Tr for controlling an interior
temperature T1 of the refrigerating compartment with a manipulation
of the temperature setting part 302, the set reference temperature
Tr is inputted into the control part 312 (step S401). In general,
since the interior temperature T1 of the refrigerating compartment
is in a range of 0.degree. C. to 5.degree. C., the reference temperature
Tr is set from 0.degree. C. to 5.degree. C.
In step S402, the control part 300 enables the cooling fan 314
to be driven in case that the interior temperature T1 of the refrigerating
compartment is higher than the reference temperature Tr of the refrigerating
compartment, so that the normal cooling operation is performed to
maintain the temperature of the refrigerating compartment at the
reference temperature Tr.
While performing the normal cooling operation, the control part
300 sets the weighted value M at "0" in case that the
cooling fan is disenabled, and sets the weighted value M at Mo in
case that the cooling fan is enabled.
In step S403, the control part 300 detects whether the door of
the refrigerating compartment is opened or closed from the door
opening/closing detection part 304 during the normal cooling operation.
In case that the door of the refrigerator is closed, the refrigerator
returns to the normal cooling operation (step S402). If the door
of the refrigerator is opened, in step S404 the control part 300
classifies the exterior temperature T0 into the temperature ranges,
and the exterior temperature is measured by means of the second
temperature detecting part 308. For example, the exterior temperature
T0 is classified into T1(T0<20.degree. C.), T2(20.degree. C..ltoreq.T0<30.degree.
C.), and T3(30.degree. C..ltoreq.T0).
In step S405, the control part 300 sets the number of rotations
RPM corresponding to each of the temperature range (step S405: RPM.rarw.RPM1
when the reference temperature T0 is included in the temperature
T1, RPM.rarw.RPM2 when the reference temperature T0 is included
in the temperature T2, and RPM.rarw.RPM3 when the reference temperature
T0 is included in the temperature T3). From Table 1, the number
of rotations RPM1 is preset at 1500, RPM2 is preset at 1700, and
RPM3 is preset at 1900.
In step S406, the number of rotations RPM of the air curtain fan
is set by adding M to the number of rotations of the preset air
curtain fan (RPM.rarw.RPM+M). That is, if the cooling fan 314 is
disenabled when the door of the refrigerating compartment is opened,
the air curtain fan is driven with the number of rotations added
by Mo to the preset number of rotations of the air curtain fan since
M=Mo(RPM.rarw.RPM+0). In the meantime, if the cooling fan is driven
when the door of the refrigerating compartment is opened, the air
curtain fan is driven with the number of rotations added by Mo to
the number of rotations of the air curtain fan since M=Mo(RPM.rarw.RPM+Mo).
From Table 1, the weighted value Mo is set at 300.
In step S407, the air curtain fan 316 is driven with the number
of rotations RPM which has been set.
TABLE 1 ______________________________________ environment COOLING
FAN OFF COOLING FAN ON air T1 T2 T3 T1 T2 T3 ______________________________________
air curtain 1500 1700 1900 1800 2000 2200 fan ______________________________________
Ex) exterior temperature ranges: T1/T2/T3
T1: T0<20.degree. C., T2: 20.degree. C..ltoreq.T0<30.degree.
C., T3: 30.degree. C..ltoreq.T0
Step S408 detects is performed whether the door of the refrigerating
compartment is closed. If the door of the refrigerating compartment
is opened, the air curtain fan 316 continues to be driven (step
S408), and if
the door of the refrigerating compartment is closed, the air curtain
fan 316 is opened (step S409), so that the air curtain fan starts
the normal cooling operation (step S402).
As stated above, according to the embodiment, the exterior temperature
is classified into several temperature ranges. The higher the exterior
temperature becomes, the higher the number of rotations of the air
curtain fan occurs. Further, if the door of the refrigerating compartment
is opened while the cooling fan is driven, the cooling fan automatically
stops. In order to compensate for this, the air curtain fan is adapted
to be driven with the number of rotations added by a weighted value
to the number of rotations of the air curtain fan. Therefore, the
air curtain fan is efficiently driven according to the interior
and exterior conditions of the compartment, so that the cooling
efficiency and electric power efficiency are enhanced.
The Second Embodiment
FIG. 3 is a block diagram for showing an air curtain fan driving
device 30 for a refrigerator according to the second embodiment
of the present invention. The second embodiment has the same structure
as the first embodiment has. However, the first embodiment classifies
into several temperature ranges the exterior temperature T0 of the
refrigerating compartment measured by the second temperature detecting
part 308, while the second embodiment classifies into several temperature
ranges the temperature difference (T0-T1) between the exterior temperature
T0 and the interior temperature T1, wherein the exterior temperature
T0 of the refrigerating compartment is measured by the second temperature
detecting part 308, and the interior temperature T1 of the refrigerating
compartment is measured by the first temperature detecting part
306. For example, the temperature difference (T0-T1) is classified
into T4(T0-T1<15.degree. C.), T5(15.degree. C..ltoreq.T0-T1.ltoreq.25.degree.
C.), and T6(25.degree. C..ltoreq.T0-T1). In order for the air curtain
fan to be driven with a higher number of rotations in a higher temperature
range, the number of rotations RPM of the air curtain fan is set
at the numbers of ratation RPM4, RPM5, and RPM6, respectively, corresponding
to temperature ranges.
Hereinafter, the air curtain fan driving method according to the
second embodiment of the present invention will be described in
detail with reference to FIG. 5. FIG. 5 is a flow chart for explaining
the air curtain fan driving method for a refrigerating compartment
according to the second embodiment of the present invention.
If a user sets a reference temperature Tr for controlling an interior
temperature T1 of the refrigerating compartment with manipulating
the temperature setting part 302, the set reference temperature
Tr is inputted into the control part 312 (step S501). In general,
since the interior temperature T1 of the refrigerating compartment
is in a range of 0.degree. C. to 5.degree. C., the reference temperature
Tr is set from 0.degree. C. to 5.degree. C.
In step S502, the control part 300 enables the cooling fan 314
to be driven in case that the interior temperature T1 of the refrigerating
compartment is higher than the reference temperature Tr of the refrigerating
compartment, so that the normal cooling operation is performed to
maintain the temperature of the refrigerating compartment at the
reference temperature Tr.
While performing the normal cooling operation, the control part
300 sets the weighted value M at "0" in case that the
cooling fan is disenabled, and sets the weighted value M at Mo in
case that the cooling fan is enabled.
In step S503, the control part 300 detects whether the door of
the refrigerating compartment is opened or closed from the door
opening/closing detection part 304 during the normal cooling operation.
If the door of the refrigerating compartment is closed, the refrigerator
returns to the normal cooling operation (step S502). If the door
of the refrigerating compartment is opened, in step (S504), the
control part 300 classifies a temperature difference (T0-T1) into
several temperature ranges, wherein the temperature T0 denotes the
exterior temperature of the refrigerating compartment measured by
means of the second temperature detecting part 308 and the temperature
T1 denotes the interior temperature of the refrigerating compartment
measured by means of the first temperature detecting part 306. For
example, as shown in Table 2, the temperature difference (T0-T1)
is classified into several temperature ranges T4(T0-T1<15.degree.
C.), T5(15.degree. C..ltoreq.T0-T1<25.degree. C.), and T6(25.degree.
C..ltoreq.T0-T1).
In step S505, the control part 300 sets the number of rotations
RPM of the air curtain fan corresponding to each of the temperature
ranges, wherein in step S505, the number of rotations is changed
from RPM4 to RPM when the temperature difference (T0-T1) is included
in T4, from RPM5 to RPM when the temperature difference (T0-T1)
is included in T5, and from RPM6 to RPM when the temperature difference
(T0-T1) is included in T6. In Table 1, the number of rotations RPM4
is set at 1500, RPM5 at 1700, and RPM6 at 1900.
In step S506, the number of rotations RPM of the air curtain fan
is set with addition of the weighted value M to the number of rotations
of air curtain fan preset, that is, RPM.rarw.RPM+M. In detail, if
the cooling fan 314 is disenabled when the door of the refrigerating
compartment is opened, the air curtain fan is enabled with the number
of the rotations of the air curtain fan which is set since the weighted
value M is 0(RPM.rarw.RPM+0).
In the meantime, if the cooling fan 314 is being driven when the
door of the refrigerating compartment is opened, the air curtain
fan is enabled with the number of rotations added by Mo to the set
number of rotations of the air curtain fan since the weighted value
M is Mo(RPM.rarw.RPM+Mo). From Table 2, the weighted value Mo is
set at 300. In step S507, the air curtain fan 316 is driven at the
number of rotations RPM.
TABLE 2 ______________________________________ environment cooling
fan OFF cooling fan ON air T4 T5 T6 T4 T5 T6 ______________________________________
number of 1500 1700 1900 1800 2000 2200 rotations of air curtain
fan ______________________________________
Ex) Temperature ranges of temperature difference between the exterior
temperature T0 and the interior temperature T1 of the refrigerating
compartment: T4/T5/T6
T4: T0-T1<20.degree. C.
T5: 20.degree. C..ltoreq.T0-T1<30.degree. C.
T6: 30.degree. C..ltoreq.T0-T1
In step S508, the control part 300 detects whether the door of
the refrigerating compartment is closed.
If the door of the refrigerating compartment is opened, the air
curtain fan 316 continues to be driven (step S508), but if the door
of the refrigerating compartment is closed, the air curtain fan
316 turns off (step S509) so that the air curtain fan 316 starts
the normal cooling operation.
As stated above, according to the second embodiment of the present
invention, an exterior temperature is classified to several temperature
ranges, and the air curtain fan is driven at a higher number of
rotations as the exterior temperature becomes higher. Further, if
the door of the refrigerating compartment is opened during the driving
of the cooling fan, the cooling fan automatically stops. Accordingly,
the control part 300 enables the air curtain fan to be driven with
the number of rotations added by a weighted value to the normal
number of rotations of the air curtain fan to compensate for the
stopping of the cooling fan, so that cooling efficiency and electric
power efficiency are enhanced by efficiently driving the air curtain
fan according to the interior and exterior conditions of the refrigerating
compartment.
It is understood that various other modifications will be apparent
to and can be readily made by those skilled in the art without departing
from the scope and spirit of this invention. Accordingly, it is
not intended that the scope of the claims appended thereto be limited
to the descriptions set forth herein, but rather that the claims
be constructed as encompassing all the features of the patentable
novelty that reside in the present invention, including all the
features that would be treated as equivalent thereof by those skilled
in the art to which this pertains. |