U.S. patent application number 15/251211 was filed with the patent office on 2017-06-01 for apparatus and method for controlling cooling fan of vehicle.
The applicant listed for this patent is Hyundai Motor Company. Invention is credited to Taewan Kim, Yeoung Jun Kim, Dong Seok Oh, Man Hee Park.
Application Number | 20170151855 15/251211 |
Document ID | / |
Family ID | 58777788 |
Filed Date | 2017-06-01 |
United States Patent
Application |
20170151855 |
Kind Code |
A1 |
Kim; Yeoung Jun ; et
al. |
June 1, 2017 |
APPARATUS AND METHOD FOR CONTROLLING COOLING FAN OF VEHICLE
Abstract
An apparatus and a method for controlling a cooling fan of a
vehicle are capable of preventing a fan motor from being damaged by
locking the fan motor in cold weather conditions. The apparatus
includes: a fan motor driving the cooling fan; and a controller
generating an operation signal for controlling the cooling fan and
providing the operation signal to the fan motor, where the
controller confirms an ignition-off time for which an ignition was
turned off when the ignition is turned on, confirms a change rate
of an air conditioner refrigerant pressure for a measurement time
when the ignition-off time exceeds a decision-possible time and an
intake air temperature is present within a predetermined
temperature, and locks the fan motor depending on the change rate
of the air conditioner refrigerant pressure.
Inventors: |
Kim; Yeoung Jun; (Suwon,
KR) ; Park; Man Hee; (Suwon, KR) ; Kim;
Taewan; (Suwon, KR) ; Oh; Dong Seok;
(Hwaseong, KR) |
|
Applicant: |
Name |
City |
State |
Country |
Type |
Hyundai Motor Company |
Seoul |
|
KR |
|
|
Family ID: |
58777788 |
Appl. No.: |
15/251211 |
Filed: |
August 30, 2016 |
Current U.S.
Class: |
1/1 |
Current CPC
Class: |
H01L 2225/06565
20130101; H01L 27/14636 20130101; H01L 2225/06524 20130101; B60H
1/00828 20130101; H01L 2224/16145 20130101; H01L 2225/06541
20130101; F01P 7/048 20130101; H01L 2225/06513 20130101; B60H
2001/3258 20130101; B60H 1/00764 20130101; B60K 11/06 20130101;
H01L 2225/06548 20130101; H01L 24/02 20130101; H01L 2224/16014
20130101; H01L 25/0657 20130101; H01L 27/1464 20130101; H01L 24/73
20130101; H01L 27/14643 20130101; F01P 11/20 20130101; H01L 24/16
20130101; H01L 2224/32012 20130101; H01L 2224/48091 20130101; F01P
2050/24 20130101; H01L 24/32 20130101; H01L 2224/02331 20130101;
H01L 2224/17106 20130101; H01L 24/17 20130101; B60H 1/321 20130101;
B60H 2001/3248 20130101; H01L 27/14634 20130101; H01L 2224/32145
20130101; H01L 2224/73203 20130101 |
International
Class: |
B60H 1/00 20060101
B60H001/00; B60H 1/32 20060101 B60H001/32; F01P 11/16 20060101
F01P011/16 |
Foreign Application Data
Date |
Code |
Application Number |
Nov 27, 2015 |
KR |
10-2015-0167590 |
Claims
1. An apparatus for controlling a cooling fan of a vehicle, the
cooling fan being installed in an engine compartment of the
vehicle, comprising: a fan motor driving the cooling fan; and a
controller generating an operation signal for controlling the
cooling fan and providing the operation signal to the fan motor,
wherein the controller confirms an ignition-off time for which an
ignition was turned off when the ignition is turned on, confirms a
change rate of an air conditioner refrigerant pressure for a
measurement time when the ignition-off time exceeds a
decision-possible time and an intake air temperature is present
within a predetermined temperature, and locks the fan motor
depending on the change rate of the air conditioner refrigerant
pressure.
2. The apparatus of claim 1, wherein: the controller confirms a
first change rate of the air conditioner refrigerant pressure for a
first measurement time, operates the cooling fan through the fan
motor by providing the operation signal to the fan motor for a
second measurement time, confirms a second change rate of the air
conditioner refrigerant pressure for the second measurement time,
and stops the operation of the cooling fan depending on the first
change rate and the second change rate.
3. The apparatus of claim 2, wherein: the controller calculates a
comparison value on the basis of the first change rate and the
second change rate, decides whether or not the comparison value is
less than or equal to a decision reference, and stops the operation
of the cooling fan in the case in which the comparison value is not
maintained for a duration in a state in which the comparison value
is less than or equal to the decision reference.
4. The apparatus of claim 1, further comprising: a state detector
including at least one of: an intake air temperature measurer
measuring the intake air temperature, a coolant measurer measuring
a coolant temperature, a speed measurer measuring a vehicle speed,
and a pressure measurer measuring the air conditioner refrigerant
pressure.
5. The apparatus of claim 1, wherein: the controller provides the
operation signal to the fan motor and locks the fan motor depending
on the change rate of the air conditioner refrigerant pressure for
the measurement time, when a compressor is operated and a vehicle
speed is 0.
6. The apparatus of claim 1, wherein: the controller turns off a
compressor when the intake air temperature is not present within
the predetermined temperature, and operates the cooling fan when a
coolant temperature is greater than or equal to a reference
temperature in a state in which the controller turns off an air
conditioner switch.
7. A method for controlling a cooling fan of a vehicle, comprising:
confirming, by a controller, an ignition-off time for which an
ignition was turned off when the ignition is turned on; deciding,
by the controller, whether or not the ignition-off time exceeds a
decision-possible time; deciding, by the controller, whether or not
an intake air temperature is present within a predetermined
temperature when the ignition-off time exceeds the
decision-possible time; and locking a fan motor, by the controller,
depending on a change rate of an air conditioner refrigerant
pressure for a measurement time when the intake air temperature is
present within the predetermined temperature.
8. The method of claim 7, wherein the locking of the fan motor
includes: confirming a first change rate of the air conditioner
refrigerant pressure for a first measurement time; operating the
cooling fan for a second measurement time; confirming a second
change rate of the air conditioner refrigerant pressure for the
second measurement time; and stopping the operation of the cooling
fan depending on the first change rate and the second change
rate.
9. The method of claim 8, wherein the stopping of the operation of
the cooling fan depending on the first change rate and the second
change rate includes: calculating a comparison value on the basis
of the first change rate and the second change rate; deciding
whether or not the comparison value is less than or equal to a
decision reference; deciding whether or not the comparison value is
maintained for a duration in a state in which the comparison value
is less than or equal to the decision reference; and stopping the
operation of the cooling fan in the case in which the comparison
value is not maintained for the duration.
10. The method of claim 9, wherein the comparison value is
calculated through an equation: C=B/A where C is the comparison
value, A is the first change rate, and B is the second change
rate.
11. The method of claim 7, wherein the locking of the fan motor
depending on the change rate of the air conditioner refrigerant
pressure for the measurement time when the intake air temperature
is present within the predetermined temperature includes: deciding
whether or not a compressor is operated when the intake air
temperature is present within the predetermined temperature;
deciding whether or not a vehicle speed is 0 when the compressor is
operated; and locking the fan motor depending on the change rate of
the air conditioner refrigerant pressure for the measurement time
when the vehicle speed is 0.
12. The method of claim 7, wherein the deciding of whether or not
the intake air temperature is present within the predetermined
temperature includes: deciding whether or not the intake air
temperature is less than a maximum temperature; and deciding
whether or not the intake air temperature is greater than or equal
to a minimum temperature when the intake air temperature is less
than the maximum temperature.
13. The method of claim 7, wherein, after the deciding of whether
or not the intake air temperature is present within the
predetermined temperature, further comprising: turning off a
compressor when the intake air temperature is not present within
the predetermined temperature; measuring a coolant temperature in a
state in which an air conditioner switch is turned off; and
operating the cooling fan when the coolant temperature is greater
than or equal to a reference temperature.
14. A non-transitory computer readable medium containing program
instructions executed by a processor, the computer readable medium
comprising: program instructions that confirm an ignition-off time
for which an ignition was turned off when the ignition is turned
on; program instructions that decide whether or not the
ignition-off time exceeds a decision-possible time; program
instructions that decide whether or not an intake air temperature
is present within a predetermined temperature when the ignition-off
time exceeds the decision-possible time; and program instructions
that lock a fan motor depending on a change rate of an air
conditioner refrigerant pressure for a measurement time when the
intake air temperature is present within the predetermined
temperature.
Description
CROSS-REFERENCE TO RELATED APPLICATION
[0001] This application claims under 35 U.S.C. .sctn.119(a) the
benefit of Korean Patent Application No. 10-2015-0167950 filed in
the Korean Intellectual Property Office on Nov. 27, 2015, the
entire contents of which are incorporated herein by reference.
BACKGROUND
[0002] (a) Technical Field
[0003] The present invention relates to an apparatus for
controlling a cooling fan of a vehicle, and more particularly, to
an apparatus and a method for controlling the cooling fan capable
of preventing damage to a fan motor by locking the fan motor in
cold weather conditions, such as winter.
[0004] (b) Description of the Related Art
[0005] Since a large amount of heat is generated in an engine of a
vehicle, a coolant is circulated in the vicinity of the engine in
order to cool the engine, thereby lowering the temperature of the
engine. A heated coolant is heat-radiated in a radiator, and a
cooling fan is installed in an engine compartment of the vehicle in
order to improve a heat radiation effect of the radiator.
[0006] The cooling fan maintains a temperature of the coolant in an
appropriate condition to prevent overheat of the engine and allow
performance of the engine to be optimized. The cooling fan is
primarily driven by a motor.
[0007] In cold weather conditions, moisture or snow is introduced
into the cooling fan, such that freezing of the cooling fan often
occurs. Therefore, at the time of the freezing of the cooling fan,
the cooling fan is not operated even in a condition in which the
cooling fan is turned on.
[0008] In such conditions, the cooling fan is not generally
operated. However, when a driver presses a defrost button in order
to remove fog or frost, an air conditioner is operated, such that
an air conditioner refrigerant pressure gradually rises. When the
air conditioner refrigerant pressure reaches a predetermined
pressure, it arrives at a region in which the cooling fan should be
operated. However, the cooling fan is not operated due to locking
of the motor caused by the freezing of the cooling fan. In
addition, when a locking time becomes long, the motor may be
damaged or, in extreme circumstances, a fire may occur in the
engine compartment.
[0009] When an external temperature sensor is present in the
vehicle, it is possible that the cooling fan is not operated at
sub-zero temperatures. However, when an external temperature sensor
is not mounted in the vehicle, an external temperature may not be
checked, such that a control may not be performed to prevent
operation of the cooling fan at sub-zero temperatures. In addition,
in such a case, the cooling fan is operated in a predetermined
condition, such that the cooling fan may be frozen, thereby causing
damage to the motor. The damage to the motor generates overheat of
the engine, which can result in significant repair costs.
[0010] The above information disclosed in this Background section
is only for enhancement of understanding of the background of the
invention and therefore it may contain information that does not
form the prior art that is already known in this country to a
person of ordinary skill in the art.
SUMMARY
[0011] The present invention provides an apparatus and a method for
controlling a cooling fan of a vehicle capable of locking a fan
motor on the basis of an intake air temperature and an air
conditioner refrigerant pressure in order to prevent damage to the
fan motor in cold weather conditions.
[0012] Further, the present invention provides an apparatus and a
method for controlling a cooling fan of a vehicle capable of
operating the cooling fan in the case in which a coolant
temperature is greater than or equal to a reference
temperature.
[0013] An exemplary embodiment of the present invention provides an
apparatus for controlling a cooling fan of a vehicle, the cooling
fan being installed in an engine compartment of the vehicle,
including: a fan motor driving the cooling fan; and a controller
generating an operation signal for controlling the cooling fan and
providing the operation signal to the fan motor, wherein the
controller confirms an ignition-off time for which an ignition was
turned off when the ignition is turned on, confirms a change rate
of an air conditioner refrigerant pressure for a measurement time
when the ignition-off time exceeds a decision-possible time and an
intake air temperature is present within a predetermined
temperature, and locks the fan motor depending on the change rate
of the air conditioner refrigerant pressure.
[0014] The confirm a first change rate of the air conditioner
refrigerant pressure for a first measurement time, operate the
cooling fan through the fan motor by providing the operation signal
to the fan motor for a second measurement time, confirm a second
change rate of the air conditioner refrigerant pressure for the
second measurement time, and stop the operation of the cooling fan
depending on the first change rate and the second change rate.
[0015] The controller may calculate a comparison value on the basis
of the first change rate and the second change rate, decide whether
or not the comparison value is less than or equal to a decision
reference, and stop the operation of the cooling fan in the case in
which the comparison value is not maintained for a duration in a
state in which the comparison value is less than or equal to the
decision reference.
[0016] The apparatus for controlling a cooling fan of a vehicle may
further include: a state detector including at least one of an
intake air temperature measurer measuring the intake air
temperature; a coolant measurer measuring a coolant temperature; a
speed measurer measuring a vehicle speed; and a pressure measurer
measuring the air conditioner refrigerant pressure.
[0017] The controller may provide the operation signal to the fan
motor and lock the fan motor depending on the change rate of the
air conditioner refrigerant pressure for the measurement time, when
a compressor is operated and a vehicle speed is 0.
[0018] The controller may turn off a compressor when the intake air
temperature is not present within the predetermined temperature,
and operate the cooling fan when a coolant temperature is greater
than or equal to a reference temperature in a state in which the
controller turns off an air conditioner switch.
[0019] Another exemplary embodiment of the present invention
provides a method for controlling a cooling fan of a vehicle by an
apparatus for controlling a cooling fan of a vehicle, including:
confirming an ignition-off time for which an ignition was turned
off when the ignition is turned on; deciding whether or not the
ignition-off time exceeds a decision-possible time; deciding
whether or not an intake air temperature is present within a
predetermined temperature when the ignition-off time exceeds the
decision-possible time; and locking a fan motor depending on a
change rate of an air conditioner refrigerant pressure for a
measurement time when the intake air temperature is present within
the predetermined temperature.
[0020] In an exemplary embodiment of the present invention, it is
possible to prevent the fan motor from freezing in cold weather
conditions, such as winter, and thus prevent damage by stopping
operation of the fan motor.
[0021] In addition, in the case in which the coolant temperature is
greater than or equal to the reference temperature, the cooling fan
is operated, thereby making it possible to prevent overheat of the
engine.
[0022] Other effects that may be obtained or are predicted by an
exemplary embodiment of the present invention will be explicitly or
implicitly described in a detailed description of the present
invention. That is, various effects that are predicted according to
an exemplary embodiment of the present invention will be described
in the following detailed description.
BRIEF DESCRIPTION OF THE DRAWINGS
[0023] FIG. 1 is a block diagram showing an apparatus for
controlling a cooling fan of a vehicle according to an exemplary
embodiment of the present invention.
[0024] FIG. 2 is a flow chart showing a method for controlling the
cooling fan of the vehicle according to an exemplary embodiment of
the present invention.
[0025] FIG. 3 is an illustrative view showing a control method when
an air conditioner switch is turned off in the method for
controlling the cooling fan of the vehicle according to an
exemplary embodiment of the present invention.
[0026] FIG. 4 is a flow chart showing a method for detecting
locking in the method for controlling the cooling fan of the
vehicle according to an exemplary embodiment of the present
invention.
[0027] FIG. 5 is an illustrative view for describing the method for
detecting locking in the method for controlling the cooling fan of
the vehicle according to an exemplary embodiment of the present
invention.
[0028] FIG. 6 is an illustrative view for describing a first change
rate and a second change rate in the method for controlling the
cooling fan of the vehicle according to an exemplary embodiment of
the present invention.
DETAILED DESCRIPTION OF THE EMBODIMENTS
[0029] It is understood that the term "vehicle" or "vehicular" or
other similar term as used herein is inclusive of motor vehicles in
general such as passenger automobiles including sports utility
vehicles (SUV), buses, trucks, various commercial vehicles,
watercraft including a variety of boats and ships, aircraft, and
the like, and includes hybrid vehicles, electric vehicles, plug-in
hybrid electric vehicles, hydrogen-powered vehicles and other
alternative fuel vehicles (e.g. fuels derived from resources other
than petroleum). As referred to herein, a hybrid vehicle is a
vehicle that has two or more sources of power, for example both
gasoline-powered and electric-powered vehicles.
[0030] The terminology used herein is for the purpose of describing
particular embodiments only and is not intended to be limiting of
the invention. As used herein, the singular forms "a," "an" and
"the" are intended to include the plural forms as well, unless the
context clearly indicates otherwise. It will be further understood
that the terms "comprises" and/or "comprising," when used in this
specification, specify the presence of stated features, integers,
steps, operations, elements, and/or components, but do not preclude
the presence or addition of one or more other features, integers,
steps, operations, elements, components, and/or groups thereof. As
used herein, the term "and/or" includes any and all combinations of
one or more of the associated listed items. Throughout the
specification, unless explicitly described to the contrary, the
word "comprise" and variations such as "comprises" or "comprising"
will be understood to imply the inclusion of stated elements but
not the exclusion of any other elements. In addition, the terms
"unit", "-er", "-or", and "module" described in the specification
mean units for processing at least one function and operation, and
can be implemented by hardware components or software components
and combinations thereof.
[0031] Further, the control logic of the present invention may be
embodied as non-transitory computer readable media on a computer
readable medium containing executable program instructions executed
by a processor, controller or the like. Examples of computer
readable media include, but are not limited to, ROM, RAM, compact
disc (CD)-ROMs, magnetic tapes, floppy disks, flash drives, smart
cards and optical data storage devices. The computer readable
medium can also be distributed in network coupled computer systems
so that the computer readable media is stored and executed in a
distributed fashion, e.g., by a telematics server or a Controller
Area Network (CAN).
[0032] Hereinafter, an operation principle of an apparatus and a
method for controlling a cooling fan of a vehicle according to an
exemplary embodiment of the present invention will be described in
more detail with reference to the accompanying drawings.
[0033] However, drawings provided below and a detailed description
to be provided below relate to one preferred exemplary embodiment
of several exemplary embodiments for effectively describing
features of the present invention. Therefore, the present invention
is not limited to only the following drawings and description.
[0034] Hereinafter, an exemplary embodiment of the present
invention will be described in detail with reference to the
accompanying drawings.
[0035] FIG. 1 is a block diagram showing an apparatus for
controlling a cooling fan of a vehicle according to an exemplary
embodiment of the present invention.
[0036] The apparatus 50 for controlling a cooling fan of a vehicle
includes a state detector 100, a controller 110, an air conditioner
switch 120, a compressor 125, a relay 130, a connector 140, a
blower assembly 150, and a cooling fan 160.
[0037] The state detector 100 detects information required in order
to control the cooling fan 160. The state detector 100 includes an
intake air temperature measurer 102, a speed measurer 104, a
pressure measurer 106, and a coolant temperature measurer 108.
[0038] The intake air temperature measurer 102 measures an intake
air temperature, which is a temperature of air introduced into the
vehicle, and provides the measured temperature to the
controller.
[0039] The speed measurer 104 measure a vehicle speed, which is a
speed of the vehicle, and provides the measured vehicle speed to
the controller.
[0040] The pressure measurer 106 measures an air conditioner
refrigerant pressure, and provides the measured air conditioner
refrigerant pressure to the controller.
[0041] The coolant temperature measurer 108 measures a coolant
temperature of an engine, and provides the measured coolant
temperature to the controller.
[0042] The controller 110 controls at least one of the state
detector 100, the air conditioner switch 120, the compressor 125,
the relay 130, the connector 140, the blower assembly 150, and the
cooling fan 160, which are components of the apparatus 50 for
controlling a cooling fan of a vehicle, in order to operate or stop
the cooling fan 160.
[0043] The controller 110 confirms an ignition-off time for which
an ignition was turned off when the ignition is turned on. The
controller 110 confirms a change rate of the air conditioner
refrigerant pressure for a measurement time when the ignition-off
time exceeds a decision-possible time and the intake air
temperature is present within a predetermined temperature. The
controller 110 performs a control to lock or normally operate a fan
motor 157 depending on the change rate of the air conditioner
refrigerant pressure. A method for controlling the cooling fan 160
in the controller 110 will be described in more detail with
reference to FIGS. 2 to 5.
[0044] For this purpose, the controller 110 may be implemented by
at least one processor operated by a predetermined program, which
may be programmed to perform the respective steps of a method for
controlling a cooling fan of a vehicle according to an exemplary
embodiment of the present invention.
[0045] The air conditioner switch 120 turns on or turns off an air
conditioner. That is, the air conditioner switch 120 may turn on or
turn off the air conditioner by a driver or the controller 110.
[0046] The compressor 125 compresses a refrigerant at a high
temperature and a high pressure to operate the air conditioner,
when the air conditioner is turned on by the air conditioner switch
120.
[0047] The relay 130 provides an operation signal to the connector
140 depending on a control of the controller 110.
[0048] The connector 140 receives the operation signal from the
relay 130 to drive the fan motor 157. To this end, the connector
140 includes a high speed connector 143, a low speed connector 146,
and a ground connector 149. The high speed connector 143 is
directly connected to the fan motor 157, and the low speed
connector 146 is connected to the fan motor 157 through a resistor
153. The ground connector 149 is connected to the fan motor 157 and
a ground. Here, the high speed connector 143, the low speed
connector 146, and the ground connector 149 may also be formed of a
switch. The connector 140 drives the fan motor 157 through the low
speed connector 146 and the resistor 153 when it receives a low
speed operation signal from the relay 130. In addition, the
connector 140 drives the fan motor 157 through the high speed
connector 143 when it receives a high speed operation signal from
the relay 130.
[0049] The blower assembly 150 includes the fan motor 157 and the
resistor 153.
[0050] The fan motor 157 rotates blades included in the cooling fan
160 to operate the cooling fan 160.
[0051] The resistor 153 adjusts a speed of the fan motor 157. That
is, the larger the resistance value of the resistor 153, the lower
the speed at which the fan motor 157 is driven.
[0052] The cooling fan 160 is driven by the fan motor 157 included
in the blower assembly 150. The cooling fan 160 maintains a
temperature of a coolant in an appropriate condition to prevent
overheat of the engine and allow performance of the engine to be
optimally exhibited.
[0053] Hereinafter, a method for controlling a cooling fan 160 in a
vehicle according to an exemplary embodiment of the present
invention will be described with reference to FIGS. 2 to 6.
[0054] FIG. 2 is a flow chart showing a method for controlling the
cooling fan of the vehicle according to an exemplary embodiment of
the present invention.
[0055] Referring to FIG. 2, the controller 110 confirms whether or
not the ignition is turned on (S210). Here, the controller 110 may
confirm whether or not the ignition is turned on by receiving an
ignition-on signal from an initial detector (not shown).
[0056] The controller 110 confirms the ignition-off time for which
the ignition was turned off (S215). That is, the controller 110 may
confirm the ignition-off time by counting a time for which the
ignition was turned off before the ignition is turned on.
[0057] The controller 110 decides whether or not the ignition-off
time exceeds the decision-possible time (S220). Here, the
decision-possible time may indicate a reference time for deciding
that the vehicle is parked in the night, and may be set by a worker
or be set through a predefined algorithm (for example, a program or
a probability model). For example, the decision-possible time may
be six hours.
[0058] The reason for deciding whether or not the ignition-off time
exceeds the decision-possible time as described above is to confirm
that the vehicle was parked in the night. In the case in which the
vehicle is parked in the night, it may be assumed that an intake
air temperature and an external air temperature are the same as
each other. Therefore, damage to the fan motor 157 may be prevented
using the intake air temperature without using an external air
temperature sensor.
[0059] The controller 110 confirms the intake air temperature
(S225) when the ignition-off time exceeds the decision-possible
time. Here, the intake air temperature may be a temperature
measured through the intake air temperature measurer when the
ignition of the vehicle is turned off.
[0060] The controller 110 decides whether or not the intake air
temperature is present within a predetermined temperature (S230).
That is, the controller 110 may decide whether or not the intake
air temperature is less than or equal to a maximum temperature, and
greater than or equal to a minimum temperature. Here, the maximum
temperature and the minimum temperature indicate reference
temperatures for deciding a temperature at which the cooling fan
160 may be frozen, and may be set by a worker or be set through a
predefined algorithm (for example, a program or a probability
model). For example, the maximum temperature may be 7.degree. C.,
and the minimum temperature may be -10.degree. C.
[0061] The controller 110 decides whether or not the compressor 125
is operated (S235) when the intake air temperature is present
within the predetermined temperature. That is, the controller 110
may decide whether the compressor 125 is in a turn-on state or a
turn-off state when the intake air temperature is greater than or
equal to the minimum temperature and is less than or equal to the
maximum temperature.
[0062] The controller 110 decides whether or not a vehicle speed is
0 (S240) when the compressor 125 is operated. That is, the
controller 110 confirms the vehicle speed provided from the speed
measurer when the compressor 125 is operated. The controller 110
decides whether or not the vehicle speed is 0 to decide whether or
not the vehicle is in an idle state. In addition, the controller
110 generates an operation signal for operating the cooling fan 160
when the vehicle speed is 0. Here, the operation signal may be a
low speed operation signal for operating the cooling fan 160 at a
low speed.
[0063] The controller 110 performs locking detection for whether to
lock or normally operate the fan motor 157 (S245). A method for
detecting locking of the fan motor will be described in detail with
reference to FIG. 4.
[0064] The controller 110 decides whether or not a locking
detection result is normal (S250).
[0065] The controller 110 stops an operation of the cooling fan 160
(S255) when the locking detection result is not normal. That is,
the controller 110 stops the operation of the cooling fan 160 and
stops an operation of the compressor 125 when the locking detection
result is locking.
[0066] Meanwhile, the controller 110 moves to S275 to operate the
cooling fan 160, when the locking detection result is normal. Here,
since a method for controlling the cooling fan 160 that is normal
is the same as or similar to a method for controlling the cooling
fan 160 that is generally used, a detailed description therefor
will be omitted.
[0067] The controller 110 confirms whether or not the ignition is
turned off (S260). That is, the controller 110 may complete the
control of the cooling fan when the ignition is turned off.
[0068] Meanwhile, the controller 110 confirms the immediately
previous state of the cooling fan (S265) when the ignition-off time
is less than or equal to the decision-possible time. That is, since
the controller 110 may decide that the vehicle is not parked in the
night when the ignition-off time is less than or equal to the
decision-possible time, a state of the cooling fan 160 that was
decided by previously turning on the ignition is confirmed.
[0069] The controller 110 decides whether or not the immediately
previous state of the cooling fan is normal (S270).
[0070] The controller 110 operates the cooling fan 160 (S275) when
the immediately previous state of the cooling fan is normal. In
addition, the controller 110 may normally drive the cooling fan 160
since it is not severe cold when the intake air temperature exceeds
the maximum temperature. Then, the controller 110 may confirm that
the ignition is turned off.
[0071] Meanwhile, the controller 110 turns off the compressor 125
(S280) when the intake air temperature is less than the minimum
temperature.
[0072] The controller 110 turns off the air conditioner switch 120
(S285) when the compressor 125 is not operated as a confirmation
result in S235, the vehicle speed is not 0 as a decision result in
S240, or the controller 110 turns off the compressor 125 in
S280.
[0073] The controller 110 confirms a coolant temperature (S290).
That is, the controller 110 receives the coolant temperature
provided from the coolant temperature measurer 108 in order to
control the cooling fan 160 and confirms the received coolant
temperature, when the air conditioner switch 120 is turned off. The
controller 110 decides whether or not the coolant temperature is
greater than or equal to a reference temperature.
[0074] The controller 110 operates the cooling fan 160 (S295) when
the coolant temperature is greater than or equal to the reference
temperature. That is, the controller 110 may lower a temperature of
the engine by operating the cooling fan 160 when the coolant
temperature is greater than or equal to the reference temperature,
in order to prevent overheat of the engine. Here, the reference
temperature indicates a reference temperature for deciding whether
or not the overheat is generated in the engine, and may be a
predetermined value. For example, as shown in FIG. 3, the reference
temperature 310 may be 105.degree. C.
[0075] The controller 110 provides the operation signal to the fan
motor 157 through the relay 130 and the connector 140, and operates
the cooling fan 160 through the fan motor 157. Here, the operation
signal is a high speed operation signal 320. Therefore, the cooling
fan 160 is operated at a high speed, thereby making it possible to
lower the temperature of the engine.
[0076] FIG. 4 is a flow chart showing a method for detecting
locking in the method for controlling the cooling fan of the
vehicle according to an exemplary embodiment of the present
invention, FIG. 5 is an illustrative view for describing the method
for detecting locking in the method for controlling the cooling fan
of the vehicle according to an exemplary embodiment of the present
invention, and FIG. 6 is an illustrative view for describing a
first change rate and a second change rate in the method for
controlling the cooling fan of the vehicle according to an
exemplary embodiment of the present invention.
[0077] Referring to FIGS. 4 to 6, the controller 110 confirms a
first change rate of the air conditioner refrigerant pressure for a
first measurement time (S410). Here, the first measurement time may
indicate a time delayed when the operation signal is transmitted
from the controller 110 to the fan motor 157 through the relay 130
and the connector 140. The reason for delaying and then
transmitting the operation signal in the controller 110 as
described above is to prevent bugs from being generated in the
relay 130, the connector 140, and the like. Here, as shown in FIG.
5, the first measurement time 510 may be a time from 0 second to a
first time. For example, the first time may be 0.5 second.
[0078] In other words, the controller 110 receives a first air
conditioner refrigerant pressure provided from the pressure
measurer 106 at 0 second, and receives a second air conditioner
refrigerant pressure provided from the pressure measurer 106 at the
first time. The controller 110 calculates the first change rate on
the basis of the first air conditioner refrigerant pressure and the
second air conditioner refrigerant pressure. Here, the first change
rate may be represented by a gradient 610, as shown in FIG. 6.
[0079] The controller 110 operates the cooling fan 160 for a second
measurement time (S420). In other words, the controller 110
provides the operation signal to the relay 130 at the first time,
and the relay 130 provides the operation signal to the connector
140. Here, the operation signal may be a low speed operation
signal. The low speed connector 146 of the connector 140 drives the
fan motor 157 through the resistor 153 when the low speed operation
signal is received. Therefore, the cooling fan 160 may be operated
by the fan motor 157.
[0080] Here, as shown in FIG. 5, the second measurement time 530
may indicate a time for which the cooling fan 160 is operated, and
may be a predetermined value. The second measurement time 530 may
be a time from the first time to a second time. For example, the
second time may be 3.5 seconds.
[0081] The controller 110 stops the operation of the cooling fan
160 at the second time(S430).
[0082] The controller 110 confirms a second change rate of the air
conditioner refrigerant pressure for the second measurement time
(S440). In other words, the controller 110 receives a third air
conditioner refrigerant pressure provided from the pressure
measurer 106 at the first time, and receives a fourth air
conditioner refrigerant pressure provided from the pressure
measurer 106 at the second time. The controller 110 calculates the
second change rate on the basis of the third air conditioner
refrigerant pressure and the fourth air conditioner refrigerant
pressure. Here, the second change rate may be represented by a
gradient 630, as shown in FIG. 6.
[0083] The controller 110 decides whether or not a total
measurement time exceeds a reference time (S450). That is, the
controller 110 adds the first measurement time and the second
measurement time to each other to generate the total measurement
time, and decides whether or not the total measurement time exceeds
the reference time.
[0084] The controller 110 decides whether or not a comparison value
is less than or equal to a decision reference (S460). In detail,
the controller 110 calculates the comparison value on the basis of
the first change rate and the second change rate. That is, the
controller 110 may calculate the comparison value through equation
1.
C=B/A [equation 1]
[0085] Here, C may indicate the comparison value, A may indicate
the first change rate, and B may indicate the second change
rate.
[0086] The controller 110 decides whether or not the comparison
value is less than or equal to the decision reference (S460). Here,
the decision reference is a reference value for deciding whether to
normally operate the fan motor 157 or lock the fan motor 157. For
example, the decision reference may be 0.7.
[0087] The controller 110 decides whether or not the comparison
value is maintained for a duration in a state in which the
comparison value is less than or equal to the decision reference
(S470). For example, the duration may be 2 seconds.
[0088] The controller 110 decides that the cooling fan 160 is
normal (S480) when the comparison value is maintained for the
duration in the state in which the comparison value is less than or
equal to the decision reference.
[0089] The controller 110 decides that the fan motor 157 is locked
(S490) in the case in which the comparison value exceeds the
decision reference or the comparison value is not maintained for
the duration in the state in which the comparison value is less
than or equal to the decision reference.
[0090] As described above, the apparatus 50 for controlling a
cooling fan of a vehicle according to an exemplary embodiment of
the present invention decides whether or not cold weather
conditions (e.g., winter) are present on the basis of the intake
air temperature of air introduced from the outside into the vehicle
when the ignition-off time exceeds the decision-possible time. In
cold weather conditions, the apparatus 50 for controlling the
cooling fan confirms the change rate of the air conditioner
refrigerant pressure to lock the fan motor 157, thereby making it
possible to prevent damage to the fan motor.
[0091] While this invention has been described in connection with
what is presently considered to be practical exemplary embodiments,
it is to be understood that the invention is not limited to the
disclosed embodiments, but, on the contrary, is intended to cover
various modifications and equivalent arrangements included within
the spirit and scope of the appended claims.
* * * * *