JP2003049646A - Electric cooling fan device for vehicle - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide an electric cooling fan device performing certain lock determination and return determination with a common duty ratio controller, in each constitution in which two electric motors are arbitrarily selected from electric motors having two or more of different rated outputs and combined. SOLUTION: A first predetermined current I1 is set to be larger than normal current Ib corresponding to the maximum duty ratio DM when the electric motors 3 having high rated output A are combined, and not larger than current Ia corresponding to the maximum duty ratio DM when the electric motors 3 having low rated output B are combined and one electric motor 2 is locked. A second predetermined current I2 is set to be not smaller than normal current Id corresponding to a protective duty ratio DP when the electric motors 3 having high rated output A are combined, and smaller than current Ic corresponding to the protective duty ratio DP when the electric motors 3 having low rated output B are combined and one electric motor 2 is locked.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an electric fan device for cooling a vehicle, and in particular, enables control when the electric fan is locked and return control when the electric fan is unlocked, and provides two or more different rated outputs. The present invention relates to an electric motor having a common duty ratio control device capable of making reliable lock determination and return determination in each configuration in which two electric motors are arbitrarily selected and combined.

[0002]

2. Description of the Related Art Conventionally, in a cooling fan device for an automobile,
In an automobile with an air conditioner (AC), the engine cooling water flowing through the radiator is cooled by operating a cooling fan.
The engine cooling water flowing through the radiator and the AC gas flowing through the AC condenser are cooled by a common cooling fan device.

Recently, an electric cooling fan unit using an electric fan as a cooling fan has been widely put into practical use. As this cooling electric fan device, there is conventionally a device that detects the water temperature of engine cooling water and controls to turn ON / OFF the electric fan with a constant water temperature value as a boundary.

However, in such control, when an electric fan having a high rated output is applied, the electric motor is turned off.
When F is switched to ON, a voltage drop occurs, for example, there is a risk of flicker of the headlamp, noise of the electric fan is large when the engine is idle, and ON / OFF switching of the electric fan is frequently performed near the constant water temperature value. There are problems such as what happens, the cooling medium cannot be cooled efficiently, and the power consumption increases.

Therefore, pulse width modulation control (PWM control)
An electric fan device for cooling using is used. In this electric fan device for cooling, the semiconductor switching element is driven to change the duty ratio according to the state of the cooling medium, and the current value of the electric motor, that is, the rotation speed of the electric fan can be arbitrarily adjusted.

For example, Japanese Patent No. 3102355 also describes an electric cooling fan device using pulse width modulation control. In this cooling electric fan device, if the electric fan locks for some reason, an abnormal increase in the current value of the electric motor that is in an overload state (overload) is detected and a lock judgment is made to determine the electric current value of the electric motor. A technique is disclosed in which the protection duty ratio is switched so as to lower the voltage.

Here, in the cooling electric fan device using the pulse width modulation control, two electric motors are selected and combined from two or more kinds of electric motors having different rated outputs according to the vehicle type. This makes it possible to realize a plurality of types of configurations having different cooling performances.

For example, when two electric motors are selected from two types of electric motors, that is, an electric motor having a high rated output and an electric motor having a low rated output, the electric motors having a high rated output are combined with each other. Configuration, a combination of an electric motor with a high rated output and an electric motor with a low rated output, a composition with a combination of electric motors with a low rated output,
The following three configurations can be realized.

[0009]

DISCLOSURE OF THE INVENTION Problems to be Solved by the Invention In an electric fan device that controls to switch ON / OFF of an electric fan with a constant water temperature value of engine cooling water as a boundary, as described above,
Especially when an electric fan with a high rated output is applied, a voltage drop may occur when the electric motor is switched from OFF to ON, for example, the headlamp may flicker, and the noise of the electric fan that is turned ON when the engine is idle is large. ON / O of the electric fan near the constant water temperature value
There are problems such as frequent switching of FFs, inefficient cooling of the cooling medium, and increased power consumption.

Further, in the electric fan device, when the electric fan is locked for some reason (for example, water resistance when running on a road under water, foreign matter getting caught, etc.), the electric motor is overloaded. Overcurrent may flow, causing problems such as disconnection of the harness, blown fuses, and damage to the control unit. Therefore, Patent Publication No. 3
In the cooling electric fan device of Japanese Patent No. 102355, when the electric fan is locked, an abnormal increase in the current value of the electric motor is detected to perform lock determination, and the protection duty ratio is switched to reduce the electric current value of the electric motor. However, it does not describe the control after the electric fan is unlocked.

That is, if the electric duty is kept unlocked even though the electric fan is unlocked, the current value of the electric motor in which the overload state has been eliminated decreases and the rotation speed of the electric fan decreases. If the state is left unattended, it is impossible to quickly cool the cooling medium, which is obviously heated up when the electric fan is locked. Eventually, the engine will overheat or the AC efficiency will deteriorate. There is also a fear.

Further, by selecting and combining two electric motors among two or more kinds of electric motors having different rated outputs according to the vehicle type, it is possible to realize a plurality of kinds of configurations having different cooling performances. Become. However, if a different motor control device is required for each configuration in order to make a reliable lock determination and lock release determination, there is a problem in that it is extremely disadvantageous in terms of cost.

An object of the present invention is to prevent damage to the duty ratio control device and the like when the electric fan is locked by using the pulse width modulation control, and to quickly cool the cooling medium when the electric fan is unlocked. In each configuration in which two electric motors are arbitrarily selected from two or more kinds of electric motors having different rated outputs and combined with each other, the common duty ratio control device ensures reliable lock judgment and return judgment. The purpose of the present invention is to provide an electric fan device for cooling a vehicle that is versatile and cost effective.

[0014]

According to a first aspect of the present invention, there is provided an electric fan device for cooling a vehicle, which includes two electric fans for cooling a cooling medium flowing through a heat exchanger of the vehicle and two electric fans for respectively driving the electric fans. Two electric motors selected from a combination of two or more different rated outputs and combined, and these electric motors are connected in parallel and driven by pulse width modulation control according to the state of the cooling medium. In a cooling electric fan device provided with a duty ratio control device for controlling, the duty ratio control device has a current value of the electric motor larger than a current value at a normal time corresponding to a maximum duty ratio in a control at a normal time. When the electric current exceeds the first predetermined current value, it is determined that at least one of the electric fans has locked, and the electric motor current value when the electric fan is locked To a protection duty ratio with a protection current value lower than the current value corresponding to the maximum duty ratio when the electric fan is locked, and the current value of the electric motor corresponding to this protection duty ratio is smaller than the protection current value. 2 When it becomes less than or equal to a predetermined current value, the electric fan is judged to be unlocked and the control returns to the normal control, and the first predetermined current value is a combination of electric motors with high rated output. Corresponds to the maximum duty ratio when one electric fan locks when electric motors with a lower rated output than the normal current value that corresponds to the above maximum duty ratio when combined are combined. It is characterized in that the current value is set to be equal to or lower than the current value.

When the electric fan is locked for some reason, an overcurrent flows in the electric motor which is in an overload state.
At that time, when the current value of the electric motor becomes equal to or higher than the first predetermined current value, it is determined that the electric fan is locked, the duty ratio is quickly switched to the protection duty ratio, and the electric current value of the electric motor is locked when the electric fan is locked. The protection current value is lower than the current value corresponding to the maximum duty ratio of. Therefore, it is possible to reliably prevent the problem that the duty ratio control device or the like is damaged or the harness around the motor is damaged.

If a duty ratio less than the maximum duty ratio is set when the electric fan locks, an electric motor driven with a duty ratio less than the maximum duty ratio immediately after the electric fan locks. The current value of 1 may not reach the first predetermined current value or more. In this case, since the electric fan is locked, the temperature of the cooling medium rises and the duty ratio also rises, and finally, the duty ratio is likely to reach the maximum duty ratio. Therefore, the current value of the electric motor becomes equal to or higher than the first predetermined current value while the duty ratio is increasing, and it is determined that the electric fan is locked at that time.

Among various configurations in which two electric motors are arbitrarily selected and combined from two or more kinds of electric motors having different rated outputs, when electric motors having high rated outputs are combined, The maximum current value corresponding to the maximum duty ratio becomes the maximum value, and when electric motors with low rated output are combined, the current value corresponding to the maximum duty ratio when one electric fan locks is the lowest. It becomes a value. Further, when electric motors having low rated outputs are combined with each other, the current value corresponding to the maximum duty ratio when the two electric fans are double-locked is naturally the minimum value or more.

That is, the first predetermined current value is larger than the current value under normal conditions corresponding to the maximum duty ratio when electric motors with high rated output are combined, and electric motors with low rated output are connected with each other. By setting the current value to a value equal to or less than the maximum duty ratio when one electric fan locks when combined, two electric motors can be arbitrarily selected from two or more electric motors having different rated outputs. In each selected and combined configuration, the common duty ratio control device makes it possible to perform a reliable lock determination when at least one electric fan is locked.

When the electric fan is unlocked, the current value of the electric motor in which the overload state has been eliminated decreases, and when it falls below the second predetermined current value, it is determined that the electric fan has been unlocked and normal control is performed. Return to. Therefore, it is possible to quickly cool the cooling medium whose temperature obviously rises when the electric fan is locked, and it is possible to prevent overheating of the engine and deterioration of the effectiveness of AC as much as possible.

According to a second aspect of the present invention, there is provided a vehicle cooling electric fan device according to the first aspect, wherein a protection current value when one of the two electric fans is locked is smaller than the first predetermined current value. It is characterized in that the protection duty ratio is set so as to be larger than a current value in a normal state corresponding to a minimum duty ratio other than 0.

When one of the two electric fans is locked,
When the protection duty ratio is set, the current value of the electric motor becomes a protection current value smaller than the first predetermined current value, and it is possible to prevent overcurrent from flowing to the electric motor as much as possible. Further, since the protection duty ratio is set so that the protection current value is larger than the current value in the normal state corresponding to the minimum duty ratio other than 0, the second predetermined current for determining that the electric fan is unlocked. The value can be reliably set to a value lower than the protection current value.

According to a third aspect of the invention, there is provided an electric fan device for cooling a vehicle according to the first aspect, wherein the second predetermined current value is
One electric fan locked when electric motors with normal rated current value corresponding to the protection duty ratio when electric motors with high rated output were combined and electric motors with low rated output were combined. In this case, the protection duty ratio is set to be less than the current value.

Among various configurations in which two electric motors are arbitrarily selected and combined from two or more kinds of electric motors having different rated outputs, when electric motors having high rated outputs are combined, The current value under normal conditions corresponding to the protection duty ratio becomes the maximum value, and when electric motors with low rated output are combined, the current value corresponding to the protection duty ratio when one electric fan locks is the lowest. It becomes a value.

That is, the second predetermined current value is equal to or higher than the current value in the normal state corresponding to the protection duty ratio when electric motors having high rated outputs are combined, and electric motors having low rated output are combined. When the two electric motors are locked together, the electric current value corresponding to the protection duty ratio when one electric fan is locked is set to less than the current value, so that two electric motors can be arbitrarily selected from two or more electric motors having different rated outputs. In each of the combined configurations, the common duty ratio control device makes it possible to perform a reliable lock release determination when at least one electric fan is unlocked after being locked.

According to a fourth aspect of the present invention, in the electric fan device for cooling a vehicle, the duty ratio is set to the maximum duty ratio for a predetermined time immediately after returning to the normal control. It is characterized by that. When the electric fan locks, it is clear that the temperature of the cooling medium rises, and immediately after the control returns to the normal state, the electric fan driven at the maximum duty ratio for a predetermined time immediately removes the increased cooling medium. Can be cooled to.

According to a fifth aspect of the present invention, there is provided an electric fan device for cooling a vehicle according to any one of the first to fourth aspects, wherein a radiator and an air conditioner condenser are provided as the heat exchanger, and the duty ratio control device distributes the radiator. In the case where the air conditioner is not in operation, the first air conditioner is provided with first operation means for calculating the duty ratio according to the water temperature of the cooling water and second operation means for calculating the duty ratio according to the gas pressure in the air conditioner condenser. , The duty ratio calculated by the first calculation means is adopted, and when the air conditioner is operating, the duty ratio calculated by the first calculation means and the second
It is characterized in that the larger duty ratio among the duty ratios calculated by the calculation means is adopted.

If the air conditioner is not operating, the first
When the duty ratio calculated by the calculation means is adopted and the air conditioner is operating, the larger duty of the duty ratio calculated by the first calculation means and the duty ratio calculated by the second calculation means. By adopting the ratio, the optimum duty ratio (current value of the electric motor) based on the temperature of the cooling water and the gas pressure in the air conditioner condenser is set, and the rotation speed of the electric fan can be optimized.

[0028]

Embodiments of the present invention will be described below. The present embodiment is an example in which the present invention is applied to a cooling electric fan device equipped with an electric fan, an electric motor, and a motor control device mounted on a vehicle such as an automobile. FIG. 1 shows a configuration diagram of a vehicle cooling electric fan device 1 (hereinafter referred to as an electric fan device 1) of the present invention.
This electric fan device 1 includes two electric fans 2 for cooling a cooling medium flowing through a heat exchanger of a vehicle, two electric motors 3 for driving the two electric fans 2, and two electric motors 3 in parallel. It is composed of a motor control device 4 and the like which are connected and drive-controlled by pulse width modulation control (PWM control) according to the state of the cooling medium. In the following description, "AC" means an air conditioner.

A radiator 5 and an air conditioner condenser 6 (AC condenser 6) are provided as the heat exchanger,
The cooling electric fan device 1 is configured to be able to cool both the engine cooling water flowing through the radiator 5 and the air conditioner refrigerant gas (AC gas) flowing through the AC condenser 6. The radiator 5 and the AC capacitor 6 are arranged side by side in the front-rear direction of the vehicle, and the two electric fans 2 are arranged side by side in the vehicle width direction so as to approach and face the radiator 5.

A battery 7 is connected to the motor control device 4, and the two electric motors 3 are operated by the battery voltage applied via the motor control device 4. Further, the motor control device 4 is connected to an engine control ECU 8 that performs engine control and AC control. This engine control E
In the CU 8, various sensor signals required for engine control are read, and among them, the engine cooling water temperature T, the air conditioner operating state, and the gas pressure P in the AC condenser 6 required for the pulse width modulation control by the motor control device 4 are read. (Predetermined pressure P1
A signal from a gas pressure switch that is turned on when the above is reached, and a signal relating to the battery voltage E and the like are output to the motor control device 4.

The motor control device 4 includes a switching element 10 composed of a MOS-FET and an electric fan control circuit 11.
It has and. The switching element 10 is driven by PWM control by the electric fan control circuit 11, and when the switching element 10 is turned on, the battery voltage E is applied to each electric motor 3, so that the electric motor 3 is driven.
The electric fan control circuit 11 receives signals from the engine control ECU 8 regarding the water temperature T of the engine cooling water, the operating state of the air conditioner, the gas pressure P of AC gas, the battery voltage E, and the current value I ( Based on the voltage value), ON / OFF switching control of the switching element 10 is performed at every minute time to change the duty ratio D (ratio of ON time of the switching element 10) to change the current value of the electric motor 3 ( An average current value) is arbitrarily adjusted to perform pulse width modulation control. As described above, since the duty ratio is output by the motor control device 4 based on the signal output from the engine control ECU 8, the duty ratio control device according to claim 1 and claim 5 is the engine control EC.
It corresponds to U8 and the motor control device 4.

In this motor control device 4, the radiator 5
The first calculation process of calculating the first duty ratio D1 according to the water temperature T of the engine cooling water flowing through the second duty ratio and the second duty according to the gas pressure P in the AC condenser 6 when the AC is operating. It is configured to perform a second calculation process for calculating the ratio D2.

In the first calculation process, as shown in FIG. 2, the water temperature T of the engine cooling water flowing through the radiator 5 is 98.
The first duty ratio D is less than 98 ° C. and 98 ° C. to 100 ° C. when the temperature rises after less than 98 ° C.
1 is determined to be 0%, and when descending after passing through a temperature of 100 ° C or higher, when the first duty ratio D1 is determined to be 30% when 98 ° C to 100 ° C, and when 100 ° C to 108 ° C. , The first duty ratio D1 is 3 in proportion to the water temperature T.
It is determined to a value within 0 to 90%.

The water temperature T of the engine cooling water is from 108 ° C to 110 ° C.
In case of 110 ° C and 112 ° C when the temperature rises below 110 ° C, the first duty ratio D1 is determined to be 90%. In the case of 110 ° C. to 112 ° C. when descending after passing through, the first duty ratio D1 is determined to be 100%.

In the second arithmetic processing, as shown in FIG.
When the gas pressure P in the C condenser 6 is less than the predetermined pressure P1, the second duty ratio D2 is determined to be 70%,
When the pressure is equal to or higher than the predetermined pressure P1, the second duty ratio D2
Is determined to be 90%. In this motor control device 4, A
When C is not operating, the first duty ratio D1 calculated in the first arithmetic processing is adopted, and when AC is operating, the first duty ratio D1 is calculated in the first arithmetic processing. And the second duty ratio D calculated in the second calculation processing
The larger duty ratio of the two is adopted.

Further, with respect to the adopted duty ratio,
A correction process corresponding to the battery voltage is performed. In this duty ratio correction processing, as shown in FIG. 4, a correction coefficient α corresponding to the battery voltage E is obtained (for example, when the reference voltage is 13.5V, the correction coefficient is 1.000, and when the voltage is 12V, the correction coefficient 1.125). Then, the correction coefficient α is multiplied by the adopted duty ratio for correction, and the corrected duty ratio is set as the duty ratio for driving the electric motor 3.

Here, in this electric fan device 1, two electric motors 3 are selected from the two kinds of electric motors 3, that is, the electric motor 3 having a high rated output A and the electric motor 3 having a low rated output B. It is possible to arbitrarily select and combine them. In this case, as shown in FIG. 5, (a) a configuration in which electric motors 3 having a high rated output A are combined, and (b) an electric motor 3 having a high rated output A and an electric motor 3 having a low rated output B are combined. Combined configuration,
(C) A total of three configurations in which the electric motors 3 having a low rated output B are combined are considered.

The electric fan 2 is locked by the electric fan 2 driven by one electric motor 3 in the configuration of FIG. 5A, and the high rated output A of the configuration of FIG. 5B. A pattern in which the electric fan 2 driven by the electric motor 3 locks, a pattern in which the electric fan 2 driven by the electric motor 3 having a low rated output B in the configuration of FIG. 5B locks, and one of the configurations in FIG. 5C Electric motor 3
And the pattern in which the electric fan 2 driven by is locked.
In each of the configurations (a) to (c), three patterns in which the two electric fans 2 are double-locked can be considered, that is, seven patterns in total.

When electric motors 3 having a high rated output A are combined as shown in FIG. 5A, the current value I of the electric motor 3 at the normal time is the maximum duty ratio DM as shown in FIG. When it is (100%), it becomes IMa1, and when one electric fan 2 is locked, the electric motor 3 that drives the electric fan 2 becomes overloaded and overcurrent flows, and the current value I of the electric motor 3 becomes IMb1. Become.

The motor controller 4 controls the electric fan 2 when the current value I of the electric motor 3 becomes equal to or larger than the first predetermined current value I1 larger than the normal current value IMa1 corresponding to the maximum duty ratio DM. Is determined to be locked, and the current value I of the electric motor 3 when the one electric fan 2 is locked is set to a protection current value IP lower than the first predetermined current value I1.
The protection duty ratio DP is set to 1 (for example, 30%).

As described above, the current value I of the electric motor 3 when one electric fan 2 is locked is IP1 when the protection duty ratio is DP, but when the electric fan 2 is unlocked, the electric fan 2 is unlocked. Since the overload state of the electric motor 3 that drives the motor is eliminated, the current value I of the electric motor 3 is I
It becomes m1.

After the motor controller 4 determines that the electric fan 2 is locked, the current value I of the electric motor 3 corresponding to the protection duty ratio DP is smaller than the protection current value IP1 by the second predetermined current value I2. When it becomes the following, it is determined that the electric fan 2 is unlocked, and the control returns to the normal control, and immediately after the control returns to the normal control, the predetermined time tc and the duty ratio D are set to the maximum duty ratio DM. It is configured as follows.

Here, when the electric fan 2 is locked and a duty ratio less than the maximum duty ratio DM is set, immediately after the electric fan 2 is locked,
The current value I of the electric motor 3 driven at a duty ratio less than the maximum duty ratio DM may not reach the first predetermined current value I1 or more. In this case, since the electric fan 2 is locked, the water temperature T of the engine cooling water of the radiator 5 rises and the gas pressure P of the AC gas in the AC condenser 6 rises, so the duty ratio D also rises. Eventually, the water temperature T of the engine cooling water rises 11
When the temperature reaches 2 ° C, the duty ratio D becomes the maximum duty ratio DM
There is a high possibility that

Therefore, while the duty ratio D is increasing, the current value I of the electric motor 3 becomes equal to or higher than the first predetermined current value I1, and it is determined that the electric fan 2 is locked at that time. Immediately after the electric fan 2 is locked, if the current value I of the electric motor 3 does not exceed the first predetermined current value I1, the time lag between the actual locking of the electric fan 2 and the lock determination becomes large. The current value I is the first predetermined current value I from the time of the actual lock of 2 to the time of the lock determination.
There is no problem because the value does not become higher than 1.

Now, considering only the case where electric motors 3 having high rated output A are combined, the first predetermined current value I1
Is set within a range that satisfies IMa1 <I1 ≦ IMb1 and the lock determination can be reliably performed, and regarding the second predetermined current value I2, Im1 ≦ I2 <I
The lock release determination can be reliably performed by setting the value within the range that satisfies P1.

However, with the first predetermined current value I1 and the second predetermined current value I2 set in this way, two electric motors 3 are arbitrarily selected from the two electric motors 3 having different rated outputs A and B. In each configuration selected and combined,
There are cases where the lock determination and the lock release determination cannot be reliably performed. Therefore, the setting of the first predetermined current value I1 for surely making the lock determination and the second predetermined current value I2 for surely making the lock release determination in each configuration will be described.

7 (i) to 7 (iv) show high rated output A
High rated output A
When the electric motor 3 of No. 1 and the electric motor 3 of low rated output B are combined, and when the electric motors 3 of low rated output B are combined, current value characteristics of all four patterns in which one electric fan 2 locks Indicates.

7 (i) to 7 (iv), when the electric motors 3 having a high rated output A are combined and one electric fan 2 is locked (i), the maximum duty ratio DM
In the case where the current value I (IMa1 to IMa4) at the time of normalization corresponding to is the highest value (IMa1) and one electric fan 2 is locked by combining the electric motors 3 with low rated output B (iv). , The current value I (IMb1 to IMb4) corresponding to the maximum duty ratio becomes the minimum value (IMb4).

That is, for the first predetermined current value I1,
A current value Ib in a normal state corresponding to the maximum duty ratio DM when the electric motors 3 having high rated outputs A are combined with each other.
A current value Ia (= IMb4) or less corresponding to the maximum duty ratio DM when one electric fan 2 is locked when electric motors 3 having a lower rated output B than (= IMa1) are combined. Is set to.

By setting the first predetermined current value I1 in this manner, two electric motors 3 having different rated outputs A and B are arbitrarily selected and combined in each constitution. The common motor control device 4 makes it possible to make a reliable lock determination when one of the electric fans 2 is locked. In addition, as shown in FIG.
The current value I corresponding to the maximum duty ratio DM when the two electric fans 2 are double-locked naturally becomes Ia or more, and therefore becomes the first predetermined current value I1 or more, and thus the lock determination can be reliably performed. Become.

On the other hand, in FIGS. 7 (i) to 7 (iv), when the electric motors 3 of high rated output A are combined and one electric fan 2 is locked (i), the protection duty ratio DP is increased. Corresponding normal current value I (Im1 to Im4)
Is a maximum value (Im1), and when one electric fan 2 is locked by combining electric motors 3 having a low rated output B (iv), a current value I (IP1 to IP1) corresponding to the protection duty ratio DP is obtained. IP4) is the lowest value.

That is, for the second predetermined current value I2,
A current value Id in a normal state corresponding to the protection duty ratio DP when the electric motors 3 having a high rated output A are combined with each other.
A current value I corresponding to the protection duty ratio DP when one electric fan 2 is locked when electric motors 3 having a lower rated output B are combined (= Im1) or more.
It is set to less than c (= IP4).

By setting the second predetermined current value I2 in this manner, two electric motors 3 having different rated outputs A and B are arbitrarily selected and combined in each constitution. The common motor control device 4 makes it possible to make a reliable lock release determination when unlocking after one of the electric fans 2 is locked.
As shown in FIG. 8, the protection duty ratio DP when the two electric fans 2 are double-locked and then unlocked
Since the current value I corresponding to is naturally less than or equal to the second predetermined current value I2, it is possible to reliably perform the lock release determination.

Incidentally, the protection current value (IP1 to IP4) when one of the two electric fans 2 is locked is smaller than the first predetermined current value I1 and the minimum duty ratio D other than 0.
The protection duty ratio DP is set so as to be larger than the current value Im4 at the normal time corresponding to m.

Next, the calculation setting control of the duty ratio performed by the motor control device 4 will be described with reference to the flowcharts of FIGS. 9 and 10. Note that Si in the flow chart
(I = 1, 2, 3, ...) Shows each step. Also,
The characteristics shown in FIG. 2, FIG. 3, and FIG. 4 are stored in the memory of the motor control device 4 as a map or an arithmetic expression associated with this control.

As shown in FIG. 9, first, engine control E
Various signals related to the engine cooling water temperature T, the operating condition of the air conditioner, the gas pressure P in the AC condenser 6 (a signal from a gas pressure switch that turns on when the pressure exceeds a predetermined pressure P1), the battery voltage E, etc. are read from the CU 8. (S1). Next, when the current value I of the electric motor 3 is not greater than or equal to the first predetermined current value I1 (S2; No), the first calculation process is executed as described above to determine the first duty ratio D1 (S).
3). Next, when the AC is operating (S4; Ye
s), the second arithmetic processing is executed as described above to determine the second duty ratio D2 (S5).

Next, the first duty ratio D1 and the second duty ratio D2 are compared (S6). When D1> D2 (S6; Yes), the first duty ratio D1 is adopted (S6).
7) If D1> D2 is not satisfied (S6; No), the second duty ratio D2 is adopted (S8). Thus, the first
The larger duty ratio of the duty ratio D1 and the second duty ratio D2 is adopted.

On the other hand, in S3, the first duty ratio D1
If the AC is not operating after the determination of (S4; No
), The first duty ratio D1 calculated in the first calculation process
Is adopted (S7). Then, as described above, the correction process (S9) is executed on the adopted duty ratio according to the battery voltage, the corrected duty ratio is set as the duty ratio of the motor drive (S10), and this duty ratio is set. The achieved control signal is output to the PWM control,
To return.

When the current value I of the electric motor 3 becomes equal to or larger than the first predetermined current value I1 (S2; Yes), it is determined that the electric fan 2 is locked, as shown in FIG. 10 (S1).
1) The current value I of the electric motor 3 is switched to the protection duty ratio DP which is the protection current value IP (S12), and then it is determined whether the current value I of the electric motor 3 is the second predetermined current value I2 or less. (S13). Current value I of electric motor 3
Is below the second predetermined current value I2 (S13; Yes), it is determined that the electric fan 2 is unlocked (S14), and the duty ratio is set to the maximum duty ratio DM (S1).
5). Immediately after that, the time is measured and when a predetermined time tc has elapsed (S16; Yes), the process returns.

According to the electric fan device 1 of the present invention, the electric motor 3 is driven and controlled by the pulse width modulation control according to the state of the cooling medium. Therefore, in the normal control, the electric fan 2 having a particularly high rated output is used. When applied, a voltage drop occurs when the electric motor 3 is switched from OFF to ON,
For example, it is possible to solve the problems that the headlamp may flicker, the noise of the electric fan 2 that is turned on when the engine is idle, the cooling medium cannot be efficiently cooled, and the power consumption increases.

Then, the motor control device 4 has the first predetermined current value I1 which is larger than the normal current values IMa1 to IMa4 corresponding to the maximum duty ratio DM in the normal control. When it becomes, it is determined that the electric fan 2 is locked, and the protection duty ratio DP is set to the protection current values IP1 to IP4. Therefore, the problem that the motor control device 4 or the like is damaged or the harness around the motor is damaged can be surely prevented.

Further, the motor control device 4 includes the electric fan 2
Is locked, the electric fan 2 unlocks when the current value I of the electric motor 3 corresponding to the protection duty ratio DP becomes equal to or less than a second predetermined current value I2 smaller than the protection current values IP1 to IP4. The determination is made to return to normal control, and the duty ratio D is set to the maximum duty ratio DM for a predetermined time tc immediately after returning to normal control.

That is, after the electric fan 2 is unlocked, the normal control is promptly returned, and immediately after the return, the electric fan 2 is driven at a high speed for a predetermined time tc, the duty ratio D is the maximum duty ratio DM. By rotating,
To quickly eliminate the risk that the engine cooling water of the radiator 5 and the cooling medium of the AC condenser 6 that have risen when the electric fan 2 is in the locked state are rapidly cooled to overheat the engine or make AC less effective. You can

In this electric fan device 1, two electric motors 3 having different rated outputs A and B have different cooling performances by selecting and combining two electric motors 3 according to the vehicle type. A plurality of types of configurations can be realized.

The first predetermined current value I1 is larger than the normal current value Ib corresponding to the maximum duty ratio DM when the electric motors 3 having a high rated output A are combined, and the rated output is low. When the electric motors 3 of B are combined with each other, the current value Ia is set to be equal to or less than the current value Ia corresponding to the maximum duty ratio DM when one electric fan 2 is locked. Therefore, in each configuration in which two electric motors 3 having two different rated outputs A and B are arbitrarily selected and combined, a common motor control device 4 can perform a reliable lock determination. It will be possible to do.

Further, the second predetermined current value I2 is not less than the normal current value Id corresponding to the protection duty ratio DP when the electric motors 3 having a high rated output A are combined, and the low rated output B is low. The current value Ic is set to be less than the current value Ic corresponding to the protection duty ratio DP when one electric fan 2 is locked when the electric motors 3 are combined. Therefore, in each of the configurations in which two electric motors 3 having two different rated outputs A and B are arbitrarily selected and combined, the common motor control device 4 can reliably perform the lock release determination. Will be able to do. result,
It is possible to provide the electric fan device 1 that is excellent in versatility and is advantageous in terms of cost.

Even when two electric motors 3 having different rated outputs are selected and combined, the first predetermined current value and the second predetermined current value are equivalent to the above. By setting the current value, it is possible to configure an electric fan device that can make reliable lock determination and lock release determination. The first predetermined current value I
The first, second predetermined current value I2, protection current value IP, and the like can be appropriately set to current values other than those in the above-described embodiment in consideration of the output of the applied electric motor 3, the battery voltage of the battery, and the like. .

Various modifications can be made and implemented without departing from the spirit of the present invention.
For example, in the present embodiment, a signal from the engine control ECU 8 is input and the motor control device 4 determines the duty ratio based on this input signal, but the following method may be used. That is, the engine control ECU 8 determines the duty ratio in the same manner as above based on the water temperature T of the engine cooling water, the operating state of the air conditioner, the gas pressure P of the AC condenser 6, and the battery voltage E. However, the duty ratio is, for example, a duty ratio at 0V-5V, and this duty ratio is output to the motor control device 4. The motor control device 4 sets 0V- based on the input duty ratio.
The electric motor 3 is converted to the duty ratio of the battery voltage E.
Drive control. Electric fan 2 by motor controller 4
When it is determined that the motor is locked, the motor control device 4
The lock duty control and the subsequent return control are performed by switching to the protection duty ratio by the engine control ECU 8 during that period.
The duty ratio input to the motor control device 4 from is canceled. Further, it goes without saying that the present invention can be applied to various cooling electric fan devices other than the cooling electric fan device.

[0069]

According to the vehicle cooling electric fan device of the first aspect, when the electric fan is locked for some reason, an overcurrent flows to the electric motor that is in an overload state.
At that time, since the current value of the electric motor becomes equal to or higher than the first predetermined current value, at that time, it is determined that the electric fan is locked, and the duty ratio is quickly switched to the protection duty ratio to change the current value of the electric motor. The protection current value can be set to be lower than the first predetermined current value, and therefore the problem that the duty ratio control device or the like is damaged or the harness around the motor is damaged can be reliably prevented.

When the electric fan is unlocked, the current value of the electric motor from which the overload condition has been eliminated decreases and becomes less than the second predetermined current value. At that time, therefore, it is determined that the electric fan has been unlocked. And returns to normal control, therefore
It is possible to quickly cool the cooling medium that obviously rises when the electric fan is locked, and it is possible to prevent overheating of the engine and deterioration of the effectiveness of AC as much as possible.

Then, as described above, the first predetermined current value I
By setting 1, in each configuration in which two electric motors are arbitrarily selected from two or more electric motors having different rated outputs and combined, at least one of the electric motors is driven by the common duty ratio control device. It is possible to make a reliable lock determination when the fan locks. Therefore, it is possible to provide an electric fan device for cooling a vehicle which is highly versatile and advantageous in terms of cost.

According to the vehicle cooling electric fan device of the second aspect, when the protection duty ratio is set when one of the two electric fans is locked, the electric current value of the electric motor becomes lower than the first predetermined electric current value. Also has a small protection current value, and it is possible to prevent overcurrent from flowing through the electric motor as much as possible. Further, since the protection duty ratio is set so that the protection current value is larger than the current value in the normal state corresponding to the minimum duty ratio other than 0, the second predetermined current for determining that the electric fan is unlocked. The value can be reliably set to a value lower than the protection current value.

According to the vehicle cooling electric fan device of the third aspect, by setting the second predetermined current value as described above, two electric motors having two or more different rated outputs can be driven. In each configuration in which the motors are arbitrarily selected and combined, the common duty ratio control device makes it possible to perform a reliable lock release determination when at least one electric fan is unlocked after being locked.

According to the vehicle cooling electric fan device of the present invention, the duty ratio is set to the maximum duty ratio for a predetermined time immediately after the normal control is restored. Therefore, when the electric fan is locked, the cooling medium is cooled. It is clear that the temperature rises, and the raised cooling medium can be quickly cooled by the electric fan driven at the maximum duty ratio for a predetermined time immediately after the control returns to the normal state.

According to the vehicle cooling electric fan device of the fifth aspect, when the air conditioner is not operating, the duty ratio calculated by the first calculating means is adopted, and when the air conditioner is operating. Adopts the larger duty ratio of the duty ratio calculated by the first calculation means and the duty ratio calculated by the second calculation means, and is based on the temperature of the cooling water and the gas pressure in the air conditioner condenser. An optimum duty ratio (current value of the electric motor) can be set to obtain an optimum rotation speed of the electric fan.

[Brief description of drawings]

FIG. 1 is a configuration diagram of an electric cooling fan device according to an embodiment of the present invention.

FIG. 2 is a characteristic diagram showing a relationship between a cooling water temperature and a first duty ratio.

FIG. 3 is a characteristic diagram showing a relationship between a pressure inside a capacitor and a second duty ratio.

FIG. 4 is a characteristic diagram showing a relationship between a battery voltage and a correction coefficient.

FIG. 5 is a schematic diagram showing a combination of electric motors.

FIG. 6 is a diagram showing a current value and a duty ratio when one electric motor is locked and unlocked when electric motors having high rated outputs are combined.

FIG. 7 is a diagram showing a current value and a duty ratio in locking and unlocking in four patterns when one electric motor is locked and unlocked.

FIG. 8 is a diagram showing current values and duty ratios in locking and unlocking in three patterns when two electric motors are double locked and unlocked.

FIG. 9 is a part of a flowchart showing calculation setting control of a duty ratio.

FIG. 10 is the rest of the flowchart showing the calculation setting control of the duty ratio.

[Explanation of symbols]

1 Electric fan device for cooling 2 electric fan 3 electric motor 4 Motor control device 5 radiator 6 Air conditioner condenser 8 Engine control ECU

─────────────────────────────────────────────────── ─── Continuation of front page (51) Int.Cl. ⁷ Identification code FI theme code (reference) H02P 7/68 H02P 7/68 J (72) Inventor Kazuya Sugiyama 3-1, Shinchi, Fuchu-cho, Aki-gun, Hiroshima Prefecture Issue Mazda Co., Ltd. F-term (reference) 3D038 AA00 AB01 AC14 AC20 5G044 AA01 AC05 AD01 CA07 CB01 CE05 5H572 AA03 BB02 BB07 CC04 DD07 EE03 HA09 HB11 HC01 HC08 JJ02 KK08 LL22 MM02

Claims (5)

[Claims] 1. From two electric fans that cool a cooling medium flowing through a heat exchanger of a vehicle and two electric motors that respectively drive these electric fans and have two or more different rated outputs. In a cooling electric fan device comprising two electric motors selected and combined, and a duty ratio control device for connecting these electric motors in parallel and performing drive control by pulse width modulation control according to the state of a cooling medium, In the control during normal operation, the duty ratio control device includes at least one of the electric fans when the current value of the electric motor becomes equal to or more than a first predetermined current value larger than the current value during normal operation corresponding to the maximum duty ratio. Is determined to have locked, and the current value of the electric motor when the electric fan is locked corresponds to the maximum duty ratio when the electric fan is locked. When the current value of the electric motor corresponding to this protection duty ratio becomes equal to or lower than the second predetermined current value smaller than the protection current value, the electric fan is switched to a protection duty ratio with a lower protection current value. It is configured to determine that the lock has been released and to return to normal control, and the first predetermined current value corresponds to the maximum duty ratio when electric motors with high rated outputs are combined with each other. A vehicle characterized by being set to a current value or less corresponding to the maximum duty ratio when one electric fan locks when electric motors having a lower rated output than the current value are combined. Electric fan device for cooling. 2. A protection current value when one of the two electric fans is locked is smaller than the first predetermined current value and larger than a normal current value corresponding to a minimum duty ratio other than 0. The electric fan device for cooling a vehicle according to claim 1, wherein the protection duty ratio is set as described above. 3. The second predetermined current value is equal to or higher than a current value in a normal state corresponding to the protection duty ratio when electric motors having high rated outputs are combined with each other, and electric motors having low rated outputs are combined. 3. The electric fan device for cooling a vehicle according to claim 1, wherein the electric fan device for cooling is set to a value less than a current value corresponding to the protection duty ratio when one electric fan is locked when combined. 4. The electric fan device for cooling a vehicle according to claim 1, wherein the duty ratio is set to the maximum duty ratio for a predetermined time immediately after returning to the normal control. . 5. A radiator and an air conditioner condenser are provided as the heat exchanger, and the duty ratio control device calculates a duty ratio according to a water temperature of cooling water flowing through the radiator, and a duty ratio controller in the air conditioner condenser. A second calculation means for calculating a duty ratio according to the gas pressure is provided, and when the air conditioner is not operating, the duty ratio calculated by the first calculation means is adopted and the air conditioner is operating. In this case, the larger duty ratio of the duty ratio calculated by the first calculation means and the duty ratio calculated by the second calculation means is adopted. An electric fan device for cooling the vehicle described.