JPH10196364A - Cooling fan control device - Google Patents

Abstract

PROBLEM TO BE SOLVED: To restrain a fan noise at idle stopping time by setting the upper limit guard rotating speed according to a demand blowoff port temperature, and setting output fan rotating speed to the upper limit guard rotating speed at idle stopping time and when reference fan rotating speed is larger than the upper limit guard rotating speed. SOLUTION: Refrigerant pressure reference fan rotating speed NP is decided from present refrigerant pressure PA/ C by using a map (S101), and for example, whether or not it is idle stopping is judged from a signal of a shift position sensor and a signal from an engine rotation sensor (S102 and S103). In case of idle stopping, the upper limit guard rotating speed NG is decided from a demand blowoff port temperature by using a map (S104). Next, whether or not it is larger than the refrigerant pressure refernce fan rotating speed NP is judged (S105), and when it is large, fan rotating speed Nf to be outputted is set as the upper limit guard rotating speed NG (S106), and is outputted to an engine computer (S108), and the fan rotating speed Nf is corrected by a water temperature, and is set as fan rotating speed Nf', and the fan rotating speed is controlled in Nf'.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a control device for a cooling fan for cooling a condenser of an air conditioner of an automobile.

[0002]

2. Description of the Related Art Conventionally, the rotation speed of a cooling fan for cooling a condenser of an air conditioner is disclosed, for example, in Japanese Patent Application Laid-Open No. 3-25371.
As disclosed in Japanese Unexamined Patent Application Publication No. 8 or as shown in FIG. 6, the number of rotations of the fan is controlled according to the refrigerant pressure of the air conditioner. If the refrigerant pressure is high, the pressure of the system increases, causing a problem in strength and a problem in that the cooling performance deteriorates. Therefore, when the refrigerant pressure is high, as shown in FIG. Was strengthened. However, in the fan speed control, there are a case where the fan speed is changed from ON to OFF as shown by a solid line in FIG. 6 and a case where the fan speed is changed linearly as shown by a broken line in FIG.

[0003]

However, the conventional cooling fan speed control has a noise problem. This is because the fan rotation speed required for cooling performance and the fan rotation speed required for noise performance generally contradict each other. That is, for example, at the time of idling while the vehicle is stopped after the sunshine, it is desired to increase the fan speed for cooling to increase the cooling performance, but to reduce the noise, it is desired to reduce the fan speed. SUMMARY OF THE INVENTION An object of the present invention is to provide a control device for a cooling fan (rotational speed) that can suppress fan noise during an idle stop where the required level of the fan noise is particularly high.

[0004]

The present invention to achieve the above object is as follows. Air conditioner current refrigerant pressure P
And the refrigerant pressure reference fan speed determining means for determining a refrigerant pressure reference fan speed N _P based on the _{A / C,} and the vehicle stop state determining means determines whether the vehicle is in a stopped state, the rotation current engine The engine speed determining means for determining whether or not the number Ne is the idle speed, the required outlet temperature determining means for determining the current required outlet temperature TA ₀ of the air conditioner, and the required outlet temperature TA ₀ . and the upper limit guard rotation speed determining means for determining an upper limit guard rotational speed N _G fans, and determining comparing means refrigerant pressure reference fan speed N _P is whether larger than the upper limit guard rotational speed N _G, vehicle stop state determining The means determines that the vehicle is currently in a stopped state, the engine speed determining means determines that the current engine speed is the idle speed, and the comparing means determines that the refrigerant pressure reference fan speed is greater than the upper limit guard speed. If it is determined the Most Set fan revolving speed N _f the upper limit guard rotational speed N _G, the refrigerant pressure based on the fan revolving speed N _f, otherwise the fan rotational speed N _P
A cooling fan control device, comprising:

Conventionally, the current refrigerant pressure P_{A / C}Based on cold
Medium pressure reference fan speed N_PThe output fan speed N_fage
I was On the other hand, in the device of the present invention, the required outlet temperature
TA₀Upper limit guard speed N according to_GDecide and eyed
At stop and N_P> N_GOutput fan speed N
_fTo N_G, So N_fIs N_PConventional that remains
, Fan noise is suppressed. Where N_GThe value of
When variable cooling is required and strong cooling is required (required outlet temperature
Degree TA₀Is low) is N_GBy increasing the value of
Cooling performance can be prioritized over noise suppression.

[0006]

DESCRIPTION OF THE PREFERRED EMBODIMENTS A cooling fan control device according to an embodiment of the present invention will be described with reference to FIGS. As shown in FIG. 1, a cooling fan 1 is mounted on a front portion of a vehicle, and a radiator 19 of an engine cooling system and a condenser 2 of an air conditioner are arranged in front of the cooling fan. The cooling fan 1 may be provided commonly to the radiator 19 and the condenser 2, or may be provided separately.

[0007] The air conditioner 2 includes a refrigerant (for example, Freon).
A condenser 2 that cools and liquefies the air; an evaporator 3 that cools the air in the cabin and evaporates and vaporizes the refrigerant itself;
The compressor includes a compressor 4 for increasing the temperature by adiabatically compressing the vaporized refrigerant, and a refrigerant pressure sensor 5 provided at an appropriate position in the refrigerant passage and linearly detecting the refrigerant pressure. The output PA _{/ C} of the refrigerant pressure sensor 5 is input to an air conditioner (air conditioner) computer 11.

The cooling fan 1 includes, for example, a hydraulic motor 6
Is driven to rotate. However, the rotation drive of the cooling fan 1 may be electric. The oil from the hydraulic pump 7 is adjusted and supplied to the hydraulic motor 6 by the duty-controlled linear solenoid valve 8. The oil after driving the hydraulic motor 6 is cooled by the oil cooler 10 and returned to the reserve tank 9. Is circulated again to the hydraulic pump 7. The rotation speed of the cooling fan 1 is controlled by controlling the amount of oil supplied to the hydraulic motor 6 with the linear solenoid valve 8.

[0009] Control of the linear solenoid valve 8 sends the fan revolving speed N _f determined by calculating air-conditioned computer 11 in communication with the engine computer 17,
The fan control signal N _f ′ from the engine computer 17
Is sent to the linear solenoid valve 8. Fan revolving speed N _f signal sent from the air conditioner computer 11 to the engine computer 17, a fan revolving speed N _f of the air-conditioning control on the fan revolving speed N _f 'signal sent from the engine computer 17 to the linear solenoid valve 8 , The fan rotation speed including the fan rotation speed _Nf from the air conditioning control to the fan rotation speed from the engine cooling water temperature control.

[0010] The air-conditioned computer 11, various signals necessary for controlling the fan revolving speed N _f is input. This signal includes a signal from the solar radiation sensor 12, a signal from the vehicle room temperature sensor 13, a driver set temperature signal,
Engine speed sensor 15 such as crank angle sensor
Ne, and the signal S from the shift position sensor 16 of the automatic transmission are included. The air-conditioner computer 11, together with the required outlet temperature TA ₀ obtained by calculation, the fan speed is the fan revolving speed N _f to be controlled in its rotational speed is determined by the calculation, in communications that fan revolving speed N _f It is sent to the engine computer 17.

A signal Ne from an engine speed sensor 15 such as a crank angle sensor, a signal from an engine coolant temperature sensor 18 and the like are input to the air conditioner computer 11, and the fan speed N _f ′ based on engine coolant temperature control is input. Is calculated. FIG. 5 shows the relationship between the cooling water temperature and the fan rotation speed N _f ′ by a solid line. Here, the higher the water temperature is, the higher the fan rotation speed N _f ′ is, and the more the water is cooled. Then, the fan rotation speed N _f ′
There is corrected as shown by the broken line in the fan revolving speed N _f from the air conditioning control, the dashed indication engine computer 17
To the linear solenoid valve 8. Conventionally, this broken line is the fan speed based on the refrigerant pressure in FIG.
It was raised and lowered according to the refrigerant pressure.

A cooling fan control device according to an embodiment of the present invention is shown in FIG.
As shown in FIG. 4, the current refrigerant pressure P of the air conditioner_{A / C}Based on
And the refrigerant pressure reference fan speed N_PDetermine the refrigerant pressure base
When the vehicle is stopped, the quasi-fan rotation speed
Vehicle stop state determination means 102 for determining whether or not
Determines whether the current engine speed Ne is an idle speed
Engine speed judging means 103 and current air conditioner
Required outlet temperature TA ₀Determine the required outlet temperature determination
Means and required outlet temperature TA₀Fan limit corresponding to
Guard rotation speed N_GUpper limit guard rotation speed determination means
104 and the refrigerant pressure reference fan speed N_PIs the upper limit guard times
Number of turns N_GComparison means 105 for determining whether or not greater than
And the vehicle stop state determining means determines that the vehicle is currently in a stop state.
And the engine speed determination means determines the current engine speed.
The rotation speed is determined to be the idle rotation speed, and the comparing means
Refrigerant pressure reference fan speed is higher than upper limit guard speed
Is determined, the fan speed N_fThe upper guard rotation speed
N_GTo (by means 106), otherwise
Fan rotation speed N_fIs the refrigerant pressure reference fan speed N_PSet to
Means (by means 107) for setting fan speed
6, 107 and the fan rotation speed N_fOutput means 1 for outputting
08. These means are air-conditioning computers
Air conditioner computer 1
The calculation is executed by one CPU.

[0013] Refrigerant pressure reference fan speed determination means 101
It is provided with a map of FIG. 2, to determine the refrigerant pressure reference fan speed N _P linearly on the basis of the output P _{A / C} of the refrigerant pressure sensor 5. The vehicle stop state determination means 102 includes a transmission shift position sensor, and determines that the vehicle is in a stop state if the shift position is in a neutral or parking position. Vehicle stop state determination means 10
2 may be a vehicle speed sensor, in which case the vehicle speed is 0
Is a vehicle stopped state.

The required outlet temperature determining means for determining the required outlet temperature TA ₀ is a means originally installed in the air conditioner computer 11, and includes a signal from the solar radiation sensor 12,
The required outlet temperature TA ₀ is determined based on a signal from the vehicle room temperature sensor 13, a driver's set temperature signal, and the like. The upper-limit guard rotation speed determining means 104 has the map shown in FIG. 3 and determines the upper-limit guard rotation speed _NG of the fan corresponding to the required outlet temperature TA ₀ .

The fan rotational speed N _f determined by means 105, 106 and 107, the refrigerant pressure reference fan speed N _P
Or the upper limit guard speed _NG (when _NP > _NG ),
This is sent to the engine computer 17 by communication, and the broken line in the map in FIG. 5 is moved up and down by the refrigerant pressure reference fan speed _NP or the upper limit guard speed _NG . That is, that the prior art has been vertically refrigerant pressure reference fan speed N _P,
In the present invention embodiment, in the case of further N _P> N _G at the time of vehicle and idling in a stop state consuming guard N _G, N _G next cooling fan speed is lower than the conventional N _P,
Noise is reduced. And this N _G
The guarded fan rotation speed N _f ′ is sent from the engine computer 17 to the linear solenoid valve 8 to control the fan rotation speed.

In the map shown in FIG. 3 provided in the upper limit guard rotation speed determining means 104, the upper limit guard rotation speed N _{G in} a region where the required outlet temperature TA ₀ is low (a region where strong cooling is desired).
The guard has been loosened. That is, when increasing the maximum guard rotational speed N _G, N _G does not become guard, N _f Remains of N _P. As a result, when the air conditioner cooling capacity is required to be high, such as after being left in the scorching sun, N _{f is set} to N _G
The guard is less likely to be applied, and cooling performance is given priority over noise.

Next, a method of controlling the number of revolutions of the fan executed by the apparatus according to the embodiment of the present invention will be described with reference to FIG.
However, FIG. 4 shows a flowchart of the control, in which the reference numerals of the units 101 to 108 correspond to those of the steps 101 to 108. The control routine of FIG. 4 is interrupted at regular time intervals. In step 101, the current refrigerant pressure P
_{From the A / C} using the map of FIG.
Determine _P. Next, at step 102, it is determined whether or not the vehicle is idling based on the signal S of the vehicle stop state determining means 102, for example, the signal S of the shift position sensor 16, and the signal Ne of the engine speed sensor 15 at step 103. If idle stop process proceeds to step 104, to determine the upper limit guard rotational speed N _G fan using the map of FIG. 3 from the required outlet temperature TA _0. Then, proceed to step 105,
Refrigerant pressure reference fan speed N _P is determined whether larger than the upper limit guard rotational speed N _G, greater Step 106
The fan revolving speed N _f to be willing output to a N _G, N _G
In guard the upper limit of the fan rotation speed N _f. Otherwise, the process proceeds to step 107, the fan revolving speed N _f to remain refrigerant pressure reference fan speed N _P. Step 10
Proceeds from 6,107 to step 108, and outputs the N _f to the engine computer 17. In FIG. 5, the engine computer 17 corrects the fan rotation speed for engine cooling water control (solid line in FIG. 5) with N _f to obtain N _f ′ (dashed line in FIG. 5), and outputs it to the linear solenoid valve 8. By controlling it, the fan speed is controlled to N _f ′.

The operation of the above apparatus and method will be described. When the shift position of the transmission is parking or neutral and the engine is in an idle state, the required outlet temperature TA _{0 in} FIG.
The upper limit guard of _NG which depends on is applied. as a result,
Particularly at the time of idling stop where the required level of the fan noise becomes high, the fan rotation speed can be kept low to suppress the noise.

However, by setting the upper limit guard rotation speed _NG to a variable value and setting the upper limit guard rotation speed _NG high when the required outlet temperature TA ₀ is low in FIG. The guard of the fan speed when TA ₀ is low can be substantially released. Thus, when the air conditioner cooling capacity is required to be high, such as after being left in the sun for a long time, the cooling performance can be given priority over noise.

[0020]

According to the cooling fan control device of the present invention,
When the vehicle is stopped and idling, an upper limit guard is applied to the fan rotation speed in accordance with the required outlet temperature TA ₀ , so that noise can be suppressed when idling is stopped.

[Brief description of the drawings]

FIG. 1 is a system diagram of an air conditioner incorporating a cooling fan control device according to an embodiment of the present invention.

FIG. 2 is a map for obtaining a fan rotation speed N _P from an air conditioner refrigerant pressure P _{A / C.}

[3] requesting outlet temperature TA ₀ from the upper limit guard rotational speed N
It is a map for finding _G.

FIG. 4 is a configuration diagram of the cooling fan control device according to the embodiment of the present invention, which is shown in the form of a flowchart.

FIG. 5 is a map for obtaining a cooling fan rotation speed from an engine cooling water temperature, and is a map showing how correction is performed based on the cooling fan rotation speed obtained from the cooling fan control device according to the embodiment of the present invention.

FIG. 6 is a map for obtaining a fan speed from an air conditioner refrigerant pressure in a conventional air conditioner.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 Cooling fan 2 Condenser 3 Evaporator 4 Compressor 5 Refrigerant pressure sensor 6 Hydraulic motor 7 Hydraulic pump 8 Solenoid valve 9 Reserve tank 10 Oil cooler 11 Air conditioner computer 12 Solar radiation sensor 13 Car room temperature sensor 15 Engine speed sensor 16 Shift position sensor 17 Engine computer Reference Signs List 18 Water temperature sensor 19 Radiator 101 Refrigerant pressure reference fan rotation speed determination means 102 Vehicle stop state determination means 103 Engine rotation speed determination means 104 Upper limit guard rotation speed determination means 105 Comparison means 106, 107 Fan rotation speed setting means 108 Output means

Claims (1)

[Claims] 1. _A refrigerant pressure reference fan rotation speed determining means for determining a refrigerant pressure reference fan rotation speed N _P based on a current refrigerant pressure P _{A / C} of an air conditioner, and determining whether or not the vehicle is in a stopped state. Vehicle stop state determining means for determining; engine speed determining means for determining whether the current engine speed Ne is an idle speed; and required outlet temperature for determining the current required outlet temperature TA ₀ of the air conditioner. a determination unit, an upper limit guard rotation speed determining means for determining an upper limit guard rotational speed N _G fan corresponding to the required outlet temperature TA _0, the refrigerant pressure reference fan or rotational speed N _P is greater than the upper guard rotational speed N _G A comparison means for judging whether or not the vehicle is in a stopped state, and an engine speed judgment means for judging that the current engine speed is an idle speed. Pressure reference fan when the rotational speed is determined to be greater than the upper limit guard rotational speed the fan revolving speed N _f of the upper guard rotational speed N _G
Set to, and the fan rotational speed setting means for setting the fan rotational speed N _f the refrigerant pressure reference fan rotational speed N _P otherwise, consisting of a cooling fan control unit.