JPS6082428A - Cooling-fan drive controller for car - Google Patents

Abstract

PURPOSE:To reduce noise by reducing the driving speed of either a radiator or a cooling fan for condenser according to the magnitude of the voltage applied onto a blower fan motor for blowing-out cooling wind when a cooler operates. CONSTITUTION:A relay 12 is turned ON by the instruction of an automatic air conditioner amplifier 13, and a compressor is driven through a clutch 14, and a blower motor 16 and a cooling fan 3 are driven at low speed by the low-voltage signal supplied from a control amplifier 15. When the cooling-water temperature exceeds 90 deg.C, a switch 20 is turned ON, and a cooling fan 4 starts revolution. When the cooling-water temperature exceeds 100 deg.C, a switch 19 is turned ON, and the cooling fan 3 is revolved at a high speed. When a large amount of cooling wind is necessitated, the voltage applied onto the motor 16 increases, and a relay 17 is turned ON, and the fan 3 is revolved always at a high speed, and only the fan 4 is revolved in accordance with the cooling-water temperature. In this case, the noise of the fan 3 is not so noisy, since the motor 16 revolves at a high speed. Thus, noise can be reduced.

Description

DETAILED DESCRIPTION OF THE INVENTION (a) Technical Field The present invention relates to a cooling fan drive control device for a vehicle that aims to reduce the noise of a cooling device that forcibly cools a radiator and a turf condenser using two cooling fans.

(B) Prior Art In a conventional vehicle equipped with a tarp, a method is known in which a condenser of a cooler cycle and a radiator of engine cooling water are cooled by a common cooling fan. This type of cooling device has two
As shown in Fig. 1, a cooler condenser l and a radiator 2 are arranged in series with respect to the air flow, and two cooling fans 3 and 4 are arranged in parallel, cooling fans 3, 4
are driven by motors 51 and 6, respectively.

On the other hand, a method has been proposed to operate two cooling fans efficiently in terms of noise, power consumption, fuel consumption, etc.
In No. 7-42095, only one cooling fan is operated intermittently depending on the engine coolant temperature when the turf is not required, so that the cooling capacity of the condenser is sufficient even when the turf is activated, such as when driving at high speed. In the resulting operating range, only one cooling fan is operated intermittently depending on the engine cooling water level, and in operating ranges such as when driving at low speeds when the cooling capacity of the condenser is insufficient, two cooling fans are operated regardless of the engine cooling water temperature. Both cooling fans are running at the same time.

By the way, in the above conventional example, the cooling state of the condenser is detected by the pressure on the high pressure side of the cooler cycle, that is, the pressure on the discharge side of the compressor of the cooler cycle. da/
When the cooling capacity is above cJ), a large cooling capacity is required, and when the cooling capacity is below that, such as when driving at high speeds, the second cooling fan is turned on and off. Therefore, when the inside of the car gets quite cold while driving at low speeds and the volume of cold air is reduced, the noise will be reduced to 1st indoor pro-fan noise, but since both cooling fans are rotating, the noise will be reduced to the inside of the car. This may extend into the cabin and cause concerns for the occupants.

Furthermore, since the discharge pressure of the compressor may fluctuate around the set pressure depending on the running speed, the second cooling fan is turned on and off frequently, causing the problem that the rotation noise of the fan becomes annoying.

e→Object and Structure of the Invention The present invention has been made in view of the above points, and it is an object of the present invention to control the drive of a cooling fan by not using the discharge side pressure of the compressor, but by using another control element instead. The purpose of this technology is to reduce the noise generated by the cooling fan when the volume of cold air is lowered in cooling mode in a cooling system that uses two cooling fans to forcibly cool the radiator and condenser of the cooler cycle. To this end, cooling fan drive control is performed to reduce the driving speed of one of the two cooling fans in accordance with the magnitude of the voltage applied to the proa fan motor for blowing cold air into the vehicle interior during cooling operation. It consists of a device.

) Example The present invention will be explained below based on the drawings.

FIG. 2 shows an embodiment of the cooling fan control device according to the present invention, and in the figure, 3 and 4 are cooling fans, and 5.6 is a cooling fan driving motor. In this embodiment, the rotational speed of the cooling fan motor 5 can be controlled in two stages depending on the presence or absence of the resistor R.

In the figure, reference numeral 10 indicates a PAP'J, llU ignition switch, and reference numeral 12 indicates a fan control amplifier which engages and disengages the clutch 14 for operating the Tala compressor in response to commands from the auto air conditioner amplifier 13, and also provides ON/OFF signals for the compressor (to be described later). The sending relay 15 is an indoor proa control amplifier that controls the voltage applied to the indoor proa 7 unmotor 16 based on the command from the auto air conditioner amplifier 13, and controls the air volume; 17 has one inference contact and one normally closed contact that are linked. relay, 18
is a fan control amplifier that switches the relay 17 on and off according to the voltage applied to the indoor pro-afan] 6 only when the compressor is on. For example, when the applied voltage is 8V or less,
J Ray] 7 is turned off, and when it is 8■ or above, relay 17 is turned on. 19 is the engine coolant temperature switch, for example 10
Turns on at 0C or higher. 20V'i is also an engine coolant temperature switch, which turns on at 90C or higher, for example. These two water temperature switches are installed along the cooling channels of the 19.20Tri radiator. 21 is the water temperature switch 20
It is a relay that can be turned on and off by turning on and off.

Next, the operation of the cooling fan control device will be explained based on the following table.

(1) Tzu cooling? When it is not needed, the relay 12 is in a non-energized state because there is no command from the auto air conditioner amplifier 13. In this case, when neither dehumidification nor heating is being performed, the voltage applied to the indoor pro fan motor 16 is O, and when dehumidifying or heating is being performed, the voltage applied to the indoor pro fan motor 16 is O.
When the voltage applied to the fan control amplifier 18 is 8V or less, the fan control amplifier 18 does not output a signal to energize the relay 173. For this purpose, the cooling fan 3, 40 rotations IU1'' is controlled only by the water temperature switch 19,20. That is, if the engine water temperature is below 90C, both water temperature switches 19, 2
Since both 0 and 0 are off, neither the proar 7 unmotor 5 nor 6 rotates. Therefore, neither the cooling fans 3 nor 4 operate. When the engine water temperature exceeds 90C, the water temperature switch 20 is turned on, the relay 21 is energized, the pro fan motor 6 is rotated, and the cooling fan 4 performs cooling.

When the engine water temperature exceeds 100C, the water temperature switch 19 is turned on in addition to the water temperature switch 20, so relays 21 and 1
7 are energized, and as a result, cooling fan 4 and cooling fan 3 rotate at high speed, and efficient cooling is performed by the two cooling fans.

On the other hand, if you remove fM or 1 love with a considerable amount of lice, mark on V1 indoor pro fan motor 16)
JD! The pressure is 8v or higher. In this case, when dehumidification is being performed, the compressor ON signal is manually input to fan control amplifier 8, so relay 17
As a result, the cooling fan 3 rotates at high speed. In this state, if the voltage applied to the indoor fan motor 16 drops below 38■ in order to reduce the amount of air flowing into the vehicle interior, the fan control amplifier 18 will no longer output relay energization number B, so the cooling fan 3 will The rotation speed is switched to low speed, and the noise generated by the cooling fan is reduced.

(2) On the other hand, when the cooler is operating, the relay 12 is energized by a command from the auto air conditioner amplifier 13, so the compressor with the clutch 14 is turned on, and when one contact of the relay 12 is closed, the relay 12 is energized. A source voltage is supplied to the normally closed contact of the relay 17, and a signal indicating that the compressor 14 is operating is input to the fan control amplifier 18. In this case, if a large amount of cold air is not required, the fan control amplifier 18 does not output an energizing signal for the relay 17 because the voltage applied to the indoor pro-fan motor 16 is less than 38 cm.

As a result, when the engine cooling water temperature is below 90'C, only the cooling fan 3 rotates at a low speed, and when it exceeds 90UF, the water temperature switch 20 is turned on, so that in addition to the low speed rotation of the cooling fan 3, the cooling fan 4 starts rotating. At this time, since the two cooling fans 3 and 4 do not rotate at very high speeds, the noise does not reach into the passenger compartment and cause discomfort to the occupants. Engine cold J7I (warm is Zoo'
If the temperature exceeds c, water temperature switch 1 is activated in addition to water temperature switch 20.
9 is turned on, the relay 17 is energized, and the cooling fan 3 is turned on.
rotates at high speed. As a result, the cooler condenser 1 and the radiator 2 are cooled by the two cooling fans 3 and 4.

In addition, in situations where a large amount of cold air is required, the pressure applied to the indoor proa fan motor 16 will be 8V or more, so the relay 17 is sent from the fan control amplifier J8.
The energizing signal is output. As a result, cooling fan 3 is the engine? ? The cooling fan 4 always rotates at high speed regardless of the water temperature, and the cooling fan 4 rotates according to the engine cooling water temperature. In this case, since the indoor lower fan itself rotates at high speed, the noise caused by the cooling fan 3 does not bother the occupants so much. In this state, the interior of the vehicle has become quite cold, so if you reduce the amount of cold air blown out, that is, the rotation speed of the indoor pro fan motor 16, the noise from the indoor pro fan motor 16 will of course decrease, but the indoor pro fan motor 16 Since the voltage applied to the fan control amplifier 8 drops to 8 V or less, the relay energizing signal from the fan control amplifier 8 is no longer output, and the rotational speed of the cooling fan 3 decreases from the high speed to the low speed.

As a result, the noise caused by the cooling fan is also reduced, and the noise no longer becomes a concern to passengers.

In this way, regardless of whether the cooler is used, as the engine coolant temperature rises, one or two cooling fans are activated to increase the cooling capacity of the radiator and condenser, and when the cooler is in use, If the rotation speed of the indoor pro fan is low, only one cooling fan is operated, or even if two V12 fans are operated, one of them is set to a low speed to reduce the effect of noise caused by the rotation of the cooling fan. When the fan rotation speed is high, the cooling fan is set to high speed to increase the cooling capacity so that the noise from the cooling fan does not disturb passengers inside the vehicle. In addition, switching from one cooling fan to two indoor Proa 7
The cooling capacity of the fan is adjusted according to the magnitude of the voltage applied to the fan, so when a large cooling capacity is required, such as immediately after getting into a vehicle that has been parked in the hot sun, the cooling capacity of the fan can be suddenly reduced. can be increased and can quickly respond to changes in the situation.

In the above embodiment, one of the two cooling fans is capable of switching between high and low speeds, but the present invention may be applied to a type of cooling fan that cannot be switched between speeds and that simply starts and stops.

(E) Detailed Description of the Invention As described above, the present invention provides a vehicle cooling system in which a radiator and a cooler condenser arranged in series with respect to the air flow are cooled by two cooling fans. The fan starts when the engine cooling water temperature exceeds a first predetermined humidity, and the second cooling fan starts when the engine cooling water temperature exceeds a second predetermined temperature higher than the first predetermined temperature or Even if the temperature is below the predetermined temperature in step 2, in the cooling mode, it starts when the voltage applied to the proa fan motor for blowing cold and hot air into the passenger compartment is above a predetermined value, so that the temperature is lower than the predetermined temperature (so-called full cool). When a large cooling capacity is required by the cooling fan, the voltage applied to the indoor proa 7 unmotor is also large, so both cooling fans start and exert maximum cooling capacity, but the single room becomes considerably cold and cold air is blown out. When the air volume is lowered, the pressure applied to the indoor proa fan motor also decreases, so 1
The cooling fan on the stand will stop, although its rotational speed will drop, and the noise caused by the cooling fan will also be reduced. In addition, since the second white cooling fan is started, stopped, or switched in speed by applying pressure to the indoor pro-a fan motor, the on-off frequency due to pressure fluctuations is not as large as in the case of switching depending on the discharge pressure of the compressor, and the fan No harsh noise is generated due to the presence or absence of rotation sound.

[Brief explanation of drawings]

FIG. 1 is a schematic diagram showing the arrangement of cooling fans in a cooling fan control device according to the present invention, and FIG. 2 is an electric circuit of an embodiment of the cooling fan control device according to the present invention. 1... Cooler capacitor, 2... Radiator, 3゜4..., 117A:/, 5.6... Cooling fan drive motor, 10... Battery, ] 1... Ignition switch , 12, 17.21...relay, 13.
...Auto air conditioner amplifier, 14...Clutch, 15
...Indoor pro-a control amplifier, 16...Indoor pro-a fan motor, 18 Kawa fan control amplifier, 19.20...Engine coolant S switch patent applicant Patent attorney representing Nissan Motor Co., Ltd. Hiroo Suzuki

Claims (1)

[Claims] In a vehicle cooling system that uses a radiator, a turf condenser, and two cooling fans for forced cooling, when one air conditioner is operating, the two cooling fans are cooled according to the voltage applied to the proa fan motor that blows cold air into the passenger compartment. A cooling fan drive control device for a vehicle, comprising a cooling fan drive control circuit that reduces the drive speed of one of the fans.