JPS6253218A - Air conditioner for vehicle - Google Patents

Abstract

PURPOSE:To prevent the rise of the coolant pressure in a condenser for cooling by revolving the fan motor of a subradiator when the coolant pressure of an air conditioner becomes over a prescribed value, in the facing state where a car is in stop. CONSTITUTION:A sensor 36 is turned-OFF when the water temperature of a main radiator is over a prescribed value, and turned-ON when the water temperature is below the prescribed value. When the above-described water temperature is over the prescribed value, the fan motor of a subradiator is driven independently of the output of a control computer 28, and when the water temperature is below the prescribed value, the fan motor is controlled by the control computer 28. When each output of a detection circuit 44 and comparison circuits 40 and 48 is all '1', namely when the engine revolution speed is over a prescribed value in racing in the case when a car is in stop and the coolant pressure is over a prescribed value, the output of the computer 28 turns-OFF a transistor 30, and turns-ON a relay contact point 26b to revolve the above-described fan motor.

Description

DETAILED DESCRIPTION OF THE INVENTION [Industrial Application Field 1] The present invention relates to an air conditioner for a vehicle, particularly an improvement that can prevent the refrigerant pressure from rising during cooling operation and perform an efficient cooling action. related to vehicle air conditioners.

[Prior Art] During cooling operation using a vehicle air conditioner, a large amount of energy is lost, which places a large load on the engine. This J: Una vehicle air conditioner is
Due to the size of the equipment, the flow rate, and safety, a vapor compression method is generally used in which the refrigerant is rapidly evaporated.

In other words, as is well known, refrigerant gas is sucked into a compressor and compressed into a high-temperature, high-pressure gas, then sent to a condenser, where it is cooled and liquefied, and then sent to an expansion valve where it rapidly expands. made to do,
It becomes a low-temperature constant silicon mist refrigerant and is sent to the evaporator.

In this evaporator, the latent heat is removed from the surrounding air and the air is vaporized and sucked into the compressor again, whereby it is repeatedly circulated through the refrigeration cycle and performs a cooling action.

However, when the air conditioner is used to continuously cool the interior of the vehicle (7J) while the engine is racing, for example when parking under the scorching sun, the cooling air temperature in the condinser becomes high and the refrigerant is not liquefied. In this case, a situation occurs in which the refrigerant pressure in the refrigerant increases abnormally.

In such cases, conventionally the operation of the compressor was temporarily stopped.

In other words, as shown in FIG. 4, in conventional air conditioner control, the fan motor 10 of the sub-radiator placed near the main radiator activates the water temperature switch when the water temperature of the main radiator exceeds a predetermined value (12°C). 12 is turned off, which causes fan relay 14
The relay coil 14a becomes de-energized and the relay contact 14b is turned on, causing the fan motor 10 of the Zabrajeta to rotate.

In addition, independently of this, there is a pressure switch 16 to the cooler.
is the refrigerant pressure of the cooler (ir+ (P 1kg/
cm 2) 4r is turned ON, and the relay 18a of the compressor cut relay 18 is energized, and the relay contact 18b is turned OFF.As a result, the drive of the relay 1J19 is stopped. View.

And again] In order to drive the NBR 1J19,
Regardless of the detected value of the radiator water temperature, a control method was adopted that maintains the refrigerant pressure in the cooler until it dries up to a constant value.

[Problem that the invention aims to solve (] [L Xia Plate Moon Meng] However, as mentioned above, when the refrigerant pressure becomes abnormally high, in order to operate the air conditioner again, the refrigerant pressure must be kept at a constant value. During this time, it became impossible to cool the passenger compartment, and the passengers had to wait for the temperature to drop to a certain level, causing discomfort for a long period of time.

Purpose of the Invention The present invention has been made to solve the above problem, and is capable of preventing F-products in the refrigerant pressure of the cooling condenser, mainly when performing cooling operation in an engine racing state when parking under the hot sun. The purpose is to provide air conditioners for vehicles.

[Means and effects for solving the problems] The vehicle air conditioner according to the present invention is applied to a vehicle equipped with a main radiator, a cooling condenser, and a Zabra radiator placed separately in the vicinity of the main radiator. Ru. This vehicle is further equipped with an engine rotation speed detection sensor, a shift position detection sensor, and a cooling capacitor refrigerant pressure detection sensor, and receives signals from each of these detection sensors and outputs a predetermined signal. It has a control computer.

As a result, when racing while the vehicle is stopped, as soon as the detection circuit determines that the engine speed is above a predetermined number and the refrigerant pressure in the cooling condenser is above a predetermined value, the fan of the brush eater with the preceding symbol is activated. Drive and pass through the cooling capacitor 1! It is characterized by avoiding an increase in IHt and preventing the hot air after passing through the main radiator from being supplied to the cooling content 1.

[Example] Hereinafter, preferred embodiments of the present invention will be described based on the drawings.

FIG. 1 is an explanatory diagram showing the flow of cooling air in a vehicle air conditioner according to the present invention.

In the figure, the vehicle to which the present invention is applied includes a main radiator 20, a cooling condenser 22, and a Zabra radiator 24 which is separately placed adjacent to the main radiator 20. Although not shown in the figure, the cooling condenser 22 includes a compressor that sucks in and compresses refrigerant gas, an expansion valve that expands the liquefied refrigerant into a mist of refrigerant, and a T that vaporizes the atomized refrigerant. It is connected to the vaporizer to form a refrigeration unit that cools the inside of the vehicle.

FIG. 2 shows the circuit configuration used in the present invention.

In the figure, a fan motor 24 of a sub-radiator 24
a is controlled by a fan relay 26, whose relay coil 26a is controlled by the control computer 2.
8, and the relay contact 26b is connected to the fan motor 24a of the libragetor 24. This relay contact 26b is turned on (made) when the relay coil 26a is in a non-excited state.

The control computer 28 includes a transistor 30;
It includes an inverter circuit 32 and an AND circuit 34, and the collector side of the transistor 30 is connected to the relay coil 26a of the fan relay 26, and the emitter side is connected to the water temperature detection sensor 36 of the main radiator 20.

Further, the input side of the AND circuit 34 receives a signal from an engine rotation speed detection sensor (tachometer) 1-1.
The comparator circuit 40 determines whether or not the rotation speed is higher than a predetermined value, and the signal from the shift position detection sensor 1 is input and the shift position is set to N (neutral) or P (par 4).
Detection circuit 44 that determines whether or not the current range is within the range. Also connected is a comparison circuit 48 which detects the cold tB pressure of the cooling condenser 22 and receives a signal from the refrigerant 46 to determine whether the refrigerant pressure is above a predetermined value.

To explain in detail the present invention according to the above configuration, first,
With the ignition switch 50 turned on, when the detection circuit 44 detects that the shift range is in the N (Go 1 - Ral) or P (parking) range (while the vehicle is stopped), the detection The circuit 44 outputs logic No. 4m II I II, and at other times (during normal running), outputs II OII. Also, the comparison circuit 4
0, the engine speed is set to a predetermined value (Nirl'1ll
l) or more, the comparator circuit 40 outputs the logic signal II 1 II, and when the engine rotation speed is less than or equal to the predetermined value (N2rp+n), the logic signal (
j II O1'' is output.

Further, the comparison circuit 48 sets the refrigerant pressure to a predetermined value (P1kO
/cm2) or more, the comparison circuit 48 outputs a logic signal 111 II, and if the refrigerant pressure is less than a predetermined value (P2k(1/cm2)),
A logic signal "'0" is output.

On the other hand, the water temperature detection sensor 36 is turned off (broken) when the water temperature of the main radiator 20 is above a predetermined value (12°C), and is turned off when the water temperature is below a predetermined value (11°C).
N (make) is done.

Therefore, the water temperature of the main radiator 20 is set to a predetermined value (12°C
) or more, regardless of the output state from the control computer 28, the fan motor 24a of the sub-radiator 24
is driven, and when the temperature is below a predetermined value (11° C.), the fan motor 24a is controlled by the output state of the control computer 28.

The output of the control computer 28 is when all three outputs of the detection circuit 44 and the comparison circuit 40.48 are II 11+,
That is, during racing when the vehicle is stopped, when the engine speed is above a predetermined number and the refrigerant pressure is above a predetermined value, the I-transistor 30 is turned off.
This binding relay contact 26b is turned on (made) and the fan motor 24a of the sub-radiator 24 rotates.

Further, when any one of the three outputs of the detection circuit 44 and the comparison circuit 40.48 is the logic signal II O11, the transistor 30 is turned on, and in this case, as described above, the water temperature detection sensor 36 is turned on. The fan motor 2/Ia of the subradiator 24 is controlled depending on the state.

In addition, engine speed N, refrigerant pressure P1, and water temperature T2
The reason why each detected value has a certain width and has so-called hysteresis is to eliminate detection errors due to fluctuations in the detected value.

Furthermore, when the fan motor 27'Ia of the sub-radiator 24 rotates, Eaff passes through the cooling condenser 22.
As i increases, the hot air after passing through the main radiator 20 is discharged to the outside of the vehicle by the fan motor 24a of the sub-radiator 24, resulting in the effect that the hot air does not go around the front surface of the cooling condenser 22.

Next, FIG. 3 shows a circuit configuration according to another embodiment circuit, and in this embodiment, except that a relay is used in place of the transistor 30 of FIG. 2 described above,
Its logical operation is the same as above.

To explain this simply, the motor fan 124a of the subradiator has a water temperature of T2 detected by the water temperature detection sensor 136.
When the water temperature is above 11°C, it is driven unconditionally, and when the water temperature is below 11°C, it is controlled according to the following regulations.

That is, a shift indicator 142 indicating the shift position
is in N (neutral) or P (park) position,
And when the refrigerant pressure is equal to or higher than P1, and furthermore, when the engine revolution speed is determined by the engine revolution speed detection sensor (tachometer) 138 to be equal to or higher than N1 ppm, the refrigerant pressure detection sensor 1/I6 is in the ON state (make), and As a result, the output side transistor 52 of the amplifier circuit 140 is in the OFF state, so that the relay contact 54b of the relay 54 remains in the ON (make) state, while the relay contact 56b of the relay 56 is in the OFF state.
It is FF (broken), and as a result, the contact 126b of the relay 126 is turned on (made), and the seven-tough fan 124a of the librageator rotates.

If the water temperature is 11° C. or lower and any one of the shift position, refrigerant pressure, and engine speed does not satisfy the above-mentioned condition 11, the fan motor 124a is not rotated.

As explained above, according to the present example, the control computer 28 controls the engine rotation speed detection sensor 38, the shift position detection sensor 42, and the refrigerant pressure detection range 'J-'.
The logic of the signal from 46 is determined, and the fan motor 24a of the sub-radiator 2/I is controlled based on the logical sum condition of this logic signal and the signal from the water temperature detection sensor 36 of the main radiator 20.

Therefore, as soon as the water temperature of the main radiator 20 reaches a predetermined value or higher, or when the refrigerant pressure of the air conditioner rises above H, the fan motor 24a of the brush brush 24 is automatically driven, and -11 = refrigerant pressure. It is possible to effectively prevent the rise in temperature and enable continuous operation of the in-house air conditioner.

[Effects of the Invention] As explained above, the present invention includes an engine rotation speed detection sensor, a shift position detection sensor, and a refrigerant pressure detection sensor for a cooling condenser, and receives and receives signals from each of these detection sensors to perform predetermined detection. By including a control computer that outputs a signal, the refrigerant pressure in the air conditioner increases, mainly in racing conditions when the vehicle is stopped.
When the pressure exceeds a certain value, the fan motor of the separate Zabrajeta is automatically rotated.
The ff1fi passing through the cooling condenser increases, and the hot air after passing through the main radiator is prevented from going around the front surface of the cooling condenser, thereby increasing the cooling effect of the cooling condenser υ.

Therefore, continuous operation of cooling the vehicle interior is possible.

4. Brief explanation of the drawings Fig. 1 is a diagram showing the flow of cooling air in the vehicle air conditioner according to the present invention, Fig. 2 is an explanatory diagram of the circuit configuration used in the present invention, and Fig. 3 is a diagram showing an embodiment of the present invention. FIG. 4 is an explanatory circuit diagram of a conventional vehicle air conditioner.

20... Main radiator 22... Cooling condenser 24...1 Nav radiator 24a...Fan motor 28... Control computer 36...Water temperature detection sensor

Claims (1)

[Claims] (1) In a vehicle equipped with a main radiator, a cooling condenser, and a sub-radiator placed separately close to the main radiator, an engine rotation speed detection sensor, a shift position detection sensor, and refrigerant pressure detection in the cooling condenser It includes a control computer that receives signals from each of these detection sensors and outputs a predetermined signal, and that the control computer detects that the engine speed is above a predetermined number of revolutions and that the cooling capacitor is When it is determined that the refrigerant pressure is equal to or higher than a predetermined value, the fan of the sub-radiator is driven to increase the amount of air passing through the cooling condenser, and at the same time, the hot air after passing through the main radiator is prevented from being supplied to the cooling condenser. A vehicle air conditioner characterized by: