JP2002307938A - Cooling fan control device for vehicle - Google Patents

Abstract

PROBLEM TO BE SOLVED: To realize a cooling fan control device for vehicle that can reduce the power consumption of a compressor without increasing electric power consumption at the off time of an electromagnetic clutch by operating a cooling fan before the operation of the compressor. SOLUTION: This cooling fan control device for the vehicle is provided with a radiator 3 for cooling a cooling liquid; a cooling fan 5 which blasts cooling air toward a condenser 4 of a refrigerating cycle having a compressor 6 for compressing a refrigerant; an electromagnetic clutch 7 intermittently connecting the compressor 6 to a drive source of a water-cooled engine 2; and an electronic control unit 10 for controlling the operation of the compressor 6 and cooling fan 5. The electronic control unit 10 has a compressor delay control means 160 for operating the compressor 6 after operating the cooling fan 5 for a prescribed time when receiving a command of connecting the electromagnetic clutch 7 during the operation of the refrigerating cycle to operate the compressor 6.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a cooling fan for cooling a radiator of a vehicle and a condenser of a refrigeration cycle and a control device of a cooling fan for a vehicle for controlling the operation of a compressor. The present invention relates to a control configuration capable of reducing power.

[0002]

2. Description of the Related Art Generally, in a refrigeration cycle, a temperature sensor such as a thermistor is provided downstream of an evaporator to prevent frost and control refrigeration capacity. It controls an electromagnetic clutch that transmits power to the compressor and a cooling fan that sends cooling air to the condenser.

At this time, since the cooling fan blows air to both the condenser and the radiator, the concrete control of the cooling fan is as described below. That is, when the actual water temperature Tw is higher than the water temperature T1 set for preventing the engine from overheating (Tw ≧ T
1) Alternatively, the actual condensing pressure Ph is set by the pressure switch provided on the high pressure side (condenser side) of the refrigeration cycle.
When it is higher than h1 (Ph ≧ Ph1), the cooling fan is operated at the maximum air volume (Hi).

When Tw <T1 and Ph <Ph1 and the electromagnetic clutch is ON, the cooling fan is operated at the minimum air flow (Lo). When Tw <T1 and the electromagnetic clutch is OFF, the cooling fan is operated. Stop. That is, in the above-described control of the cooling fan, when the air conditioner switch is turned on under a condition that the heat load is relatively low, the refrigerating capacity is in an excess state, and therefore the cooling fan repeats the ON (Lo) state and the OFF state. become.

[0005]

The inventors of the present invention have conducted a study on the power consumption of a compressor in order to improve the efficiency (coefficient of performance) of a refrigeration cycle, and have found the following points. That is, when the cooling fan is operating, since the cooling air is being blown toward the condenser and the radiator, a portion of the engine room downstream of the cooling air flow from the condenser and the radiator is outside the engine room. The atmospheric pressure (static pressure) has increased.

For this reason, when the cooling fan is stopped in a state where the vehicle speed is reduced (idling operation state), the air once passed through the condenser and the radiator is heated by the pressure difference between the inside and outside of the engine room. The backflow to the radiator side (front side of the vehicle) causes the backflow of hot air to raise the ambient temperature of the condenser, and the next time the electromagnetic clutch is turned on and the cooling fan is activated, the hot air is released. It will pass through a condenser and a radiator. Therefore, the pressure inside the condenser (condensing pressure)
At the same time, the discharge pressure of the compressor increases, so that the power consumption of the compressor increases.

In order to reduce the power consumption of the compressor, the applicant has proposed that when the vehicle air conditioner is operating, the vehicle speed is not more than a predetermined speed regardless of whether the electromagnetic clutch is in the ON-OFF state. At the time of operation, a patent application (described in Japanese Patent Application Laid-Open No. 2000-18037) for operating the cooling fan was filed. According to this application, the power consumption of the compressor could be reduced, but the following problems might occur. I found something.

That is, even when the electromagnetic clutch is OFF, the cooling fan is always operated when the vehicle speed is lower than a predetermined speed or when the cooling water temperature is within a predetermined low water temperature range. It has been found that the cooling fan operates even in a situation other than the situation where the temperature of the side rises, resulting in an increase in power consumption.

Therefore, an object of the present invention has been made in view of the above-mentioned point. By operating a cooling fan prior to operation of a compressor, power consumption when an electromagnetic clutch is turned off can be increased. An object of the present invention is to provide a control device for a vehicle cooling fan that can reduce power consumption of a compressor.

[0010]

In order to achieve the above object, the technical means described in claims 1 to 5 is adopted. That is, according to the first aspect of the present invention, condensation of a refrigeration cycle including a radiator (3) for cooling a coolant of a liquid-cooled internal combustion engine (2) for running a vehicle and a compressor (6) for compressing a refrigerant. A cooling fan (5) for blowing cooling air toward the compressor (4), an electromagnetic clutch (7) for connecting and disconnecting the compressor (6) with a drive source of the liquid-cooled internal combustion engine (2), and a compressor (6). ) And control means (10) for controlling the operation of the cooling fan (5). The control means (10) operates the compressor (6) by connecting the electromagnetic clutch (7) during the operation of the refrigeration cycle. The cooling fan (5)
After operating for a predetermined time, the compressor (6) is operated by delay control means (160).

According to the first aspect of the present invention, the radiator (3) has the delay control means (160) for operating the compressor (6) after operating the cooling fan (5) for a predetermined time. After the hot air heated through the condenser (4) and sent back into the engine room, the compressor (6) can be operated. Therefore, when the compressor (6) operates, the outside pressure of the cool air is fed into the condenser (4), so that the condensing pressure in the condenser (4) and the discharge pressure of the compressor (6) increase. The power consumption of the compressor (6) can be reduced.

According to the second aspect of the present invention, there is provided a vehicle speed sensor (12) for detecting a vehicle speed, and a delay control means (16).
0) is characterized in that delay control is performed when the vehicle speed detected by the vehicle speed sensor (12) is equal to or lower than a predetermined speed (V1).

According to the second aspect of the invention, when the vehicle speed is equal to or higher than the predetermined speed (V1), the outside air is circulated through the radiator (3) and the condenser (4) due to the traveling pressure caused by traveling. Therefore, the ambient temperature of the condenser (4) does not rise, but when the vehicle speed is equal to or lower than the predetermined speed (V1), for example, by performing delay control during idling operation, the radiator (3) and the condenser (4) are controlled. After the heated hot air that has passed through and is sent back into the engine room, the compressor (6) can be operated. Therefore, the same effect as the first aspect is obtained.

According to a third aspect of the present invention, there is provided a water temperature sensor (11) for detecting the temperature of the coolant, and the delay control means (160) determines whether the water temperature detected by the water temperature sensor (11) is a predetermined temperature ( T1) The delay control is performed in the following cases.

According to the third aspect of the invention, when the coolant temperature is equal to or higher than the predetermined temperature (T1), the cooling fan (5) operates to cool the radiator (3). Although the atmospheric temperature of the vessel (4) does not rise, the water temperature is passed through the radiator (3) and the condenser (4) by performing the delay control when the water temperature is equal to or lower than the predetermined temperature (T1). The compressor (6) can be operated after the hot air is sent back into the engine room. Therefore, the same effect as the first aspect is obtained.

According to a fourth aspect of the present invention, there is provided a vehicle speed sensor (12) for detecting a vehicle speed and a water temperature sensor (11) for detecting a temperature of a coolant, and a delay control means (160).
Indicates that delay control is performed when the vehicle speed detected by the vehicle speed sensor (12) is equal to or lower than the predetermined speed (V1) and the water temperature detected by the water temperature sensor (11) is equal to or lower than the predetermined temperature (T1). Features.

According to the present invention, the vehicle speed is equal to or lower than the predetermined speed (V1) and the water temperature is equal to or lower than the predetermined temperature (T1).
1) By performing the delay control at the following times, the compressor (6) is operated after the warm air heated through the radiator (3) and the condenser (4) is again sent into the engine room. be able to. Therefore, the same effect as the first aspect is obtained.

According to a fifth aspect of the present invention, the delay control means (160) controls the cooling fan (5) for a predetermined time so as to have a lower drive output than after the predetermined time. .

According to the fifth aspect of the present invention, the drive output for ensuring the amount of air blown such that the heated hot air passes through the condenser (4) within a predetermined time may be sufficient. The power consumption of the cooling fan (5) can be reduced by lowering the drive output after the operation of (6).

Note that the reference numerals in parentheses of the above means indicate the correspondence with the concrete means of the embodiment described later.

[0021]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS An embodiment of a control device for a vehicle cooling fan according to the present invention will be described below with reference to FIGS. First, as shown in FIG. 1, it is a schematic diagram of a vehicle engine room 1 using a control device of a vehicle cooling fan for controlling the operation of a cooling fan and a compressor according to the present embodiment. Engine (liquid-cooled internal combustion engine)
2, a radiator 3 for cooling the cooling water (cooling liquid) and a condenser 4 for a refrigeration cycle (vehicle air conditioner or vehicle refrigeration device) are disposed on the upstream side of the air flow (vehicle front side). .

Reference numeral 5 denotes an electric cooling fan driven by a motor for blowing air (cooling air) to the condenser 4 and the radiator 3. The amount of air blown to the condenser 4 and the radiator 3 is applied to the cooling fan 5. It is controlled by controlling the voltage (applied voltage). Reference numeral 6 denotes a compressor that compresses a refrigerant, and the compressor 6 operates by receiving driving force from the water-cooled engine 2 via an electromagnetic clutch 7 that transmits driving force intermittently. Reference numeral 8 denotes an evaporator that evaporates the depressurized refrigerant via a decompressor (not shown) that depressurizes the refrigerant flowing out of the condenser 4. Note that reference numeral 9 denotes an air conditioning unit that accommodates the evaporator 8, and the air conditioning unit 9 is disposed in the vehicle interior.

The electromagnetic clutch 7 and the cooling fan 5 are controlled by an electronic control unit (hereinafter, referred to as an ECU) 10 as control means.
As shown in FIG. 2, the detected water temperature Tw of the water temperature sensor 11 for detecting the temperature of the cooling water, the detected speed N of the vehicle speed sensor 12 for detecting the speed of the vehicle, the A / C switch 1 of the air conditioner for the vehicle.
3, a signal Ph, a detection pressure Ph of the pressure sensor 14 for detecting the high-pressure side pressure (pressure in the condenser 4) of the refrigeration cycle, and a detection temperature of the temperature sensor 15 for detecting the temperature of the air cooled by the evaporator 8. Te has been entered.

Next, the characteristic operation of the present invention will be described with reference to the flowcharts shown in FIGS. First, as shown in FIG. 3, in step 100, it is determined whether the vehicle air conditioner (refrigeration cycle) is operating based on the state of the A / C switch 13 (ON / OFF). When the vehicle air conditioner is stopped (when the A / C switch 13 is OFF), in step 110, it is determined whether the detected water temperature Tw is equal to or higher than a predetermined temperature T1.

Here, when the detected water temperature Tw is equal to or higher than the predetermined temperature T1, the cooling fan 5 is operated at the maximum air flow (Hi) in step 120. On the other hand, when the detected water temperature Tw is lower than the predetermined temperature T1, the flow proceeds to step 120. At 130, the cooling fan 5 remains stopped. Note that the predetermined temperature T1
Is a set temperature for preventing overheating of the water-cooled engine 2, which is about 90 ° C. in the present embodiment.

When the vehicle air conditioner is operating (when the A / C switch 13 is ON), at step 140, the vehicle speed (detected speed V) is increased to a predetermined speed V1.
It is determined whether or not the above is true. When the detected speed is equal to or higher than the predetermined speed V1, the process proceeds to step 170, and when the detected speed is lower than the predetermined speed V1, the process proceeds to step 150. Note that the predetermined speed V1 is a predetermined speed of 10 km / h or less, and is approximately 0 km / h in the present embodiment.

Then, at step 150, the detected water temperature Tw
Is higher than or equal to a predetermined temperature T1. here,
When the detected water temperature Tw is equal to or higher than the predetermined temperature T1, the process proceeds to step 170. When the detected water temperature Tw is lower than the predetermined temperature T1, the process proceeds to step 160. Here, as the compressor delay control means, when there is an ON command of the electromagnetic clutch 7 during the operation of the refrigeration cycle, the cooling fan 5
Is operated, and after a predetermined time has elapsed, the electromagnetic clutch 7 is connected and the compressor 6 is operated.

As shown in FIG. 4, first, at step 161
Then, the ECU 10 determines whether or not there is an operation request of the electromagnetic clutch 7 (operation command of the compressor 6) determined by the operation state of the refrigeration cycle. Specifically, the temperature sensor 1
5 is turned on when the detected temperature is 4 ° C. or higher, and is turned off when the detected temperature is 3 ° C. or lower.
Control signal (ON / OFF) to the compressor 6
When the control signal to is ON, at step 162
As shown in FIG. 5, a driving voltage is output so as to operate the cooling fan 5 with the minimum air flow (Lo). Thereby, air outside the vehicle compartment is sucked into the engine room 1 via the condenser 4 and the radiator 3.

Next, counting of the timer is started in step 163, and in step 164, it is determined whether or not the elapsed time TM from the start of counting has reached a predetermined time TM1. In the present embodiment, the predetermined time TM
If 1 is for about 2 seconds, the hot air heated by passing through the condenser 4 and the radiator 3 and the condenser 4 flows back into the engine room again to discharge the hot air by sending in the air from outside. The optimal time that can be set is.

After the elapsed time TM has reached the predetermined time TM1, the electromagnetic clutch 7 is connected to the drive source of the water-cooled engine 2 in step 165, and the compressor 6 is operated. As a result, as shown in FIG. 5, after the cooling fan 5 operates, the electromagnetic clutch 7 is connected to the drive source of the water-cooled engine 2 and the compressor 6 operates after a predetermined time TM1 has elapsed.

Then, after the electromagnetic clutch 7 is connected, in step 166, the timer counter in step 163 is reset here. When the detected speed in step 140 (shown in FIG. 3) is equal to or higher than the predetermined speed V1, and when the detected water temperature Tw in step 150 (shown in FIG. 3) is the predetermined temperature T1.
In the next step 170 when the above is the case, the cooling fan 5 and the electromagnetic clutch 7 are simultaneously connected or the electromagnetic clutch 7 is set to 0 N at the same time, and then the cooling fan 5 is connected to the electromagnetic clutch 7 based on the detected pressure Ph of the pressure sensor 14 of the condenser 4. The cooling fan 6 may be turned on when the pressure becomes equal to or greater than the predetermined pressure value Ph0.

When the detected pressure Ph is equal to or higher than the predetermined pressure Ph1, the cooling fan 5 is operated at the maximum air volume (Hi) to increase the heat radiation of the condenser 4, while the detected pressure Ph is lower than the predetermined pressure Ph1. , The cooling fan 5
Is operated with the minimum air flow (Lo). Here, the predetermined pressure P
h1 is a set pressure for preventing damage to the refrigeration cycle (the condenser 4 and the compressor 6).

According to the above-described embodiment, when the operation command of the compressor 6 is issued during the operation of the refrigeration cycle,
When the cooling fan 5 is stopped in the idling operation state in which the vehicle speed is reduced, the hot air once passed through the condenser 4 and the radiator 3 is heated by the pressure difference between the inside and outside of the engine room, thereby causing the condenser 4 and the radiator to cool. It flows backward to the third side (the front side of the vehicle). Therefore, by operating the cooling fan 5 first, the electromagnetic clutch 7 can be engaged after a predetermined time after the hot air that has passed through the condenser 4 and the radiator 3 and is heated is again sent into the engine room. Therefore, when the compressor 6 operates, cold air from the outside is fed into the condenser 4, so that it is possible to prevent the condensing pressure in the condenser 4 and the discharge pressure of the compressor 6 from increasing, so that the compressor 4 can be prevented from rising. 6 can reduce power consumption.

Furthermore, when the operation command of the compressor 6 is received, the operation start timing of the cooling fan 5 and the electromagnetic clutch 7 (compressor 6) is only shifted, and the cooling fan is turned off when the electromagnetic clutch is turned off as in the conventional case. 5 need not be operated, and an increase in power consumption can be suppressed. Also, there is an effect of suppressing an increase in the load on the alternator (generator) during idling operation.

Further, the detected coolant temperature Tw of the cooling liquid is equal to a predetermined temperature T.
When the temperature is equal to or more than 1, the cooling fan 5 is operating to cool the radiator 3. Therefore, when the detected water temperature Tw is only equal to or lower than the predetermined temperature T <b> 1, the cooling fan 5 needs to be pre-cooled, thereby reducing the power consumption of the cooling fan 5. Can be smaller.

In steps 150 and 160, when the detected water temperature Tw is lower than the predetermined temperature T1, the delay control of the electromagnetic clutch 7 is always performed.
When the temperature is lower (T2 or less), the delay control may be stopped because the ambient temperature of the condenser 4 is low, and the delay control of the electromagnetic clutch 7 in step 160 may be performed when T1 ≧ Tw ≧ T2.

In step 162, by operating the cooling fan 5 with the minimum air flow (Lo), the amount of air blown such that the heated hot air passes through the condenser 4 side within a predetermined time is ensured. Since the drive output is sufficient, the compressor 6
The power consumption of the cooling fan 5 can be reduced by lowering the operating voltage after the operation of the cooling fan 5.

(Other Embodiments) In one embodiment described above,
In the compressor delay control means in step 160, the cooling fan 5 was operated with the minimum air flow (Lo), but is not limited to this. As shown in FIG. 6, the blower voltage is gradually increased from 0 V within a predetermined time TMI. Control to make it (Fig. 6 (b))
You may. Thereby, it is possible to obtain a sensitivity in which the noise of only the cooling fan 5 before the compressor 6 operates is lessened than in the embodiment.

[Brief description of the drawings]

FIG. 1 is a schematic view showing a mounted state of a control device for a vehicle cooling fan according to an embodiment of the present invention.

FIG. 2 is a schematic diagram showing a control system of a control device for a vehicle cooling fan according to an embodiment of the present invention.

FIG. 3 is an electronic control unit 10 according to an embodiment of the present invention.
5 is a flowchart showing the control processing of FIG.

FIG. 4 is a flowchart illustrating a control process of a compressor delay control unit according to the embodiment of the present invention.

FIG. 5 is a time chart illustrating control processing of a compressor delay control unit according to the embodiment of the present invention.

FIG. 6 is a time chart illustrating a control process of a compressor delay control unit according to another embodiment.

[Explanation of symbols]

 2 ... water-cooled engine (liquid-cooled internal combustion engine) 3 ... radiator 4 ... condenser 5 ... cooling fan 6 ... compressor 7 ... electromagnetic clutch 10 ... electronic control unit, ECU (control means) 11 ... water temperature sensor 12 ... vehicle speed sensor 160: compressor delay control means (delay control means) T1: predetermined temperature TM1: predetermined time V1: predetermined speed

Claims (5)

[Claims] 1. A refrigeration cycle condenser (4) having a radiator (3) for cooling a coolant of a liquid-cooled internal combustion engine (2) for running a vehicle and a compressor (6) for compressing a refrigerant. A cooling fan (5) for sending cooling air to the compressor, an electromagnetic clutch (7) for connecting and disconnecting the compressor (6) to and from a drive source of the liquid-cooled internal combustion engine (2), the compressor (6) and the compressor Control means (10) for controlling the operation of the cooling fan (5), wherein the control means (10) connects the electromagnetic clutch (7) during the operation of the refrigeration cycle to connect the compressor (6).
A delay control means (160) for operating the cooling fan (5) for a predetermined time and then operating the compressor (6) upon receipt of a command to operate the cooling fan. apparatus. 2. A vehicle speed sensor for detecting a vehicle speed.
The delay control means (160) performs delay control when the vehicle speed detected by the vehicle speed sensor (12) is equal to or lower than a predetermined speed (V1).
3. The control device for a vehicle cooling fan according to claim 1. 3. A water temperature sensor (11) for detecting a temperature of the cooling liquid, wherein the delay control means (160) detects that the water temperature detected by the water temperature sensor (11) is a predetermined temperature (T).
1) The control device for a vehicle cooling fan according to claim 1, wherein delay control is performed in the following cases. 4. The vehicle speed sensor (1) for detecting a vehicle speed.
2) and the water temperature sensor (11) for detecting the temperature of the coolant, wherein the delay control means (160) is configured to control the vehicle speed detected by the vehicle speed sensor (12) to be equal to or lower than a predetermined speed (V1). The control device for a vehicle cooling fan according to claim 1, wherein the delay control is performed when the water temperature detected by the water temperature sensor (11) is equal to or lower than a predetermined temperature (T1). 5. The delay control means (160) controls the cooling fan (5) during the predetermined time so as to have a lower drive output than after the predetermined time. 3. The control device for a vehicle cooling fan according to claim 1.