JP3010799B2 - Vehicle cooling system - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a vehicle cooling system for cooling a condenser and a radiator of an air conditioner.

[0002]

2. Description of the Related Art In recent years, most vehicles have been equipped with an air conditioner, and a condenser as a radiator in the air conditioner is provided with a motor fan for cooling a radiator for maintaining an appropriate temperature of an engine. Is cooled together with the radiator. In these vehicle cooling devices, high-speed (HI) rotation and low-speed (LO) rotation of the motor fan are switched only by the water temperature of the radiator, regardless of whether the air conditioner is on or off, to blow air.
For example, as shown in FIG. 4 and FIG.
In the region below 00 ° C, all motor fans rotate LO,
In the region where the radiator water temperature is 100 ° C. or higher, all the motor fans are controlled to rotate at the HI speed (for example, published in September 1987 by Nissan Motor Co., Ltd.
No. 88).

Further, in the case of ordinary automobiles, the capacity of the alternator is large, and the motor fan has a large capacity, for example, 160 W or more in order to increase the air volume. Therefore, usually to reduce fan noise,
Even when the motor fan is used while being controlled at a low speed (LO) rotation, for example, at an output of around 110 W, since the air volume is relatively large, the cooling performance, particularly the air conditioning performance of the air conditioner, is affected. Was almost nonexistent.

[0004]

However, the alternator of an air conditioner used in a small vehicle or a vehicle smaller than a small vehicle has a small capacity and therefore a small amount of power generation, so that it can sufficiently cope with an electric load when the motor fan is operated. In some cases, it may not cut. The fan motor capacity is 110 W at HI rotation and 7 W at LO rotation.
Since it is about 0 W, the air conditioning performance may be affected due to the shortage of the air volume during the LO rotation.

For example, as shown in FIG. 5, in a region where the radiator water temperature is 100 ° C. or less, all the motor fans rotate at LO and the amount of air blows is reduced, so that the heat radiation capability of the capacitor is reduced. So, for example, in summer,
The cool-down performance immediately after the start of the engine is about 1 minute at room temperature 10 minutes later than when the motor fan is running at HI.
deg higher.

SUMMARY OF THE INVENTION The present invention has been made in view of the above-mentioned problems, and reduces the frequency of low-speed (LO) rotation of the motor fan and increases the condenser capacity of the condenser while preventing the battery from running down, thereby improving the efficiency of the air conditioner. It is an object of the present invention to provide a vehicle cooling device capable of performing various operations.

[0007]

According to the present invention, there is provided a motor fan for cooling a condenser and a radiator of an air conditioner mounted on a vehicle as shown in FIG.
When the battery 7 GaTakashi charged by the alternator 9
First detecting means 11 for detecting whether the battery is in a charged state or a discharged state ;
A second detection unit for detecting whether the heat load of the radiator is equal to or greater than a predetermined value; and a first detection unit for detecting a discharge state of the battery when the air conditioner is on, and heat load of the radiator 3 by the detection means WC is when it is detected is below a predetermined value and gist that a control unit 11 for reducing the blowing capacity of the fan motor 5.

[0008]

The cooling device for a vehicle according to the present invention, when the condenser 1 and the radiator 3 of the air conditioner mounted on the vehicle are cooled by the motor fan 5, when the air conditioner is on, the first detecting means 11 is used. When the discharge state of the battery 7 is detected by the second detection means WC and the heat load of the radiator 3 is detected to be equal to or less than a predetermined value by the second detection means WC, the blowing capacity of the motor fan 5 is reduced. Reduced the state of reduced fan blowing capacity. Thereby, the efficient operation of the air conditioner can be measured.

[0009]

An embodiment according to the present invention will be described below with reference to the drawings. FIG. 1 is a block diagram showing a schematic configuration of a vehicle cooling device according to the present invention.

In FIG. 1, a condenser (condenser) 1
Is a radiator in the air conditioner, which dissipates heat of the refrigerant which has been compressed by a compressor (not shown) and has a temperature higher than the outside air temperature, and liquefies the refrigerant.

The radiator 3 is disposed between the condenser 1 provided at the front of the vehicle and a motor fan 5 to be described later, while the cooling water, which has absorbed heat generated by the engine, circulates in the radiator 3. The cooling water is cooled by the vehicle speed wind and the cooling wind by the motor fan 5.
The radiator 3 is provided with a water temperature sensor WC as second detection means for detecting the temperature of the water circulating in the radiator 3, and information on the radiator water temperature obtained by the water temperature sensor WC is used as a water temperature signal. Are output to an engine control unit 11 described later.

The motor fan 5 receives power supplied from a battery 7 and an alternator (alternating current generator) 9 to rotate the fan and cool the condenser 1 and the radiator 3. At this time, the power supplied from the battery 7 and the alternator 9 is configured to be supplied from one of two systems, a high-speed (HI) rotation-side system and a low-speed (LO) rotation-side system. Specifically, high speed (HI)
The rotation side system is an engine control unit 11 described later.
High-speed relay 13 whose opening and closing are controlled by switch
The low-speed (LO) rotating side system is connected to the power supply side via
Similarly, the low-speed side relay 15 whose opening and closing are controlled by the engine control unit 11 and the power supplied to the motor fan 5 are reduced.
17 for rotating the fan at low speed to reduce the blowing capacity
And connected to the power supply side.

The engine control unit 11 controls the opening and closing of the switches of the high-speed relay 13 and the low-speed relay 15 to switch the rotation speed of the motor fan 5, and the direction of the current at the plus (+) electrode of the battery 7. , That is, a first detection means for detecting a charge state and a discharge state from a battery current value signal, and a water temperature signal obtained by a water temperature sensor WC and ON / OFF of an air conditioner. Signal (shown by A / C signal in the figure)
Is entered.

Next, the operation of this embodiment will be described with reference to FIGS. First, when it is assumed that the power supply of the air conditioner is off at first, the water temperature sensor WC is determined in step S1.
The water temperature signal from is acquired. Here, when the radiator water temperature exceeds 100 ° C., the rotation speed of the motor fan 5 becomes high (HI), and the radiator is cooled strongly. On the other hand, when the radiator water temperature is equal to or lower than 100 ° C. in step S1, the process proceeds to step S3. When the power of the air conditioner is turned on in step S3, the process proceeds to step S5, where the battery current value signal is fetched,
The polarity of the current direction at the plus (+) electrode of the battery 7 is determined. In this step S5, the direction of the current is positive,
That is, the high speed (HI) rotation state of the motor fan 5 is continued when in the charging state, and the motor fan 5 is in the LO rotation state when the direction of the current is negative, that is, in the discharging state. Similarly, if the power supply of the air conditioner remains off in step S3, the motor fan 5 enters the LO rotation state.

As described above, in this embodiment, when the air conditioner is on, the discharge state of the battery 7 is detected by the engine control unit 11, and the heat load of the radiator 3 is reduced to a predetermined value by the water temperature sensor WC. The blow capacity of the motor fan 5 when the condenser 1 and the radiator 3 of the air conditioner mounted on the vehicle are cooled by the motor fan 5 by reducing the blow capacity of the motor fan 5 when it is detected that Was reduced. This makes it possible to reduce the frequency of the LO rotation of the motor fan and increase the condenser capacity of the condenser while preventing the battery from running down.

[0016]

As described above, according to the present invention, when the air conditioner is turned on, the battery 7 is discharged,
In addition, since the blowing capacity of the motor fan is reduced only when the heat load of the radiator 3 is equal to or less than a predetermined value,
It is possible to reduce the frequency of low-speed rotation of the motor fan and to increase the condenser capacity of the condenser while preventing the battery from running out, thereby enabling efficient operation of the air conditioner.

[Brief description of the drawings]

FIG. 1 is a block diagram showing one embodiment of the present invention.

FIG. 2 is a flowchart illustrating the operation of the vehicle cooling device shown in FIG. 1;

FIG. 3 is a diagram for explaining the operation of the vehicle cooling device shown in FIG. 1;

FIG. 4 is a flowchart for explaining the operation of the conventional device.

FIG. 5 is a diagram for explaining the operation of a conventional device.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 Condenser 3 Radiator 5 Motor fan 7 Battery 9 Alternator 11 Engine control unit 13 High speed side relay 15 Low speed side relay 17 Register WC Water temperature sensor

Claims (1)

(57) [Claims] 1. A motor fan for cooling a condenser and a radiator of an air conditioner mounted on a vehicle, and whether a battery charged by an alternator is in a charged state.
First detecting means for detecting whether the battery is in a discharge state, second detecting means for detecting whether the heat load of the radiator is equal to or less than a predetermined value, and when the air conditioner is on, the first detecting means is a battery. discharge state detecting and cooling vehicle heat load of the radiator in the second detection means, characterized in that a control means for reducing the blowing capacity of the fan motor when it is detected is equal to or less than a predetermined value apparatus.