JPH0664029U - Vehicle air conditioner - Google Patents

Abstract

(57) [Abstract] [Purpose] To provide a vehicle air conditioner capable of reasonably suppressing a dynamic overload in the initial state of operation of an electric compressor and easily improving followability to a cooling request. Is. [Structure] A tank 8 that stores cooling water outside the refrigerant circuit 1.
And detecting the high pressure side pressure in the refrigerant circuit 1,
A pressure detector 9 that outputs a supply instruction signal when the pressure on the high-pressure side exceeds a predetermined value, and according to the supply instruction signal from the pressure detector 9, draws cooling water from the tank 8 and arranges it near the condenser 4. The electric pump 10 for supplying the nozzle 11 is provided. The pressure detection device 9 detects the high-pressure side pressure of the refrigerant circuit 1 and operates the electric pump 10 when the high-pressure side pressure causes a dynamic overload on the electric compressor 3. As a result, cooling water is injected into the condenser 4 to remove the latent heat of vaporization, and the heat dissipation capability of the condenser 4 temporarily increases.

Description

[Detailed description of the device]

[0001]

[Industrial applications]

 The present invention particularly relates to a vehicle air conditioner having a function of reducing a dynamic load on a compressor in a refrigerant circuit during a cooling operation.

[0002]

[Prior art]

 FIG. 3 shows the basic configuration of a conventional vehicle air conditioner. The refrigerant circuit 1 in the figure includes a compressor, for example, an electric compressor 3 in which an electric motor that is a drive unit and a compression operation unit that is a driven unit are housed in a casing, a condenser 4, a receiver dryer 7, It includes an expansion valve 5 and an evaporator 6, which are connected in series via a pipe.

The electric compressor 3 compresses the low-pressure gas-phase refrigerant flowing from the evaporator 6 and sends it to the condenser 4 as a high-pressure gas-phase refrigerant. The high-pressure gas-phase refrigerant is radiatively condensed by the condenser 4, becomes a high-pressure liquid-phase refrigerant, flows into the receiver dryer 7, is dehumidified therein, and then flows into the expansion valve 5. When passing through the expansion valve 5, the refrigerant changes from the high pressure liquid phase to the low pressure gas-liquid mixed phase due to the throttling effect of the expansion valve 5. The low-temperature gas-liquid mixed-phase cooling medium that has passed through the expansion valve 5 flows into the evaporator 6. In the evaporator 6, the low-pressure gas-liquid mixed-phase refrigerant absorbs heat, becomes a low-pressure gas-phase refrigerant, and returns to the electric compressor 3. With the operation of the air conditioner, the cooling medium moves in the refrigerant circuit 1 as indicated by an arrow M and undergoes a phase transition. Such a refrigerant phase transition is repeated during the operation of the air conditioner.

[0004]

[Problems to be solved by the device]

 In the case of a vehicle air conditioner equipped with the above-mentioned electric compressor, the transient heat load in the initial operation state becomes large, for example, when the air conditioner is used in the cooling operation such as midsummer. To rise. Under these conditions, the required torque (proportional to the required power) of the electric compressor increases.

FIG. 4 is a characteristic diagram showing the magnitude P (vertical axis) of the high-pressure side pressure in the initial state of operation of the electric compressor in relation to the elapsed time t (horizontal axis). According to this characteristic curve C1, the peak of the magnitude P of the high-pressure side pressure that appears at the elapsed time Δt greatly exceeds the magnitude P _{R of the} reference pressure. This excess pressure is a dynamic excess load for the electric compressor.

As described above, when an air conditioner including an electric compressor that operates in a dynamic overload state is provided in a vehicle driven by an internal combustion engine, fuel efficiency of the internal combustion engine deteriorates. Moreover, if such an air conditioner is installed in an electric vehicle, power consumption will deteriorate.

Therefore, as a measure against a dynamic overload of the electric compressor, a motor having a large driving force is used so that the electric compressor can rotate at a high speed even in a state of a dynamic overload, or a condenser is used. It is possible to use a large condenser to improve the heat dissipation capacity of the vessel. However, according to such measures, there is a problem that it is difficult to realize the recent demands for various kinds of vehicles, that is, the size reduction and weight reduction of the air conditioner itself, or the ease of mounting thereof.

On the other hand, as another countermeasure against the dynamic overload, if the rotation speed of the motor of the electric compressor is decreased and the torque is increased, the cooling capacity will decrease at the initial stage. It takes time to obtain a desired vehicle interior temperature.

In any case, since the dynamic overload temporarily occurs in the initial state, these various measures are irrational.

The present invention has been made to solve such a problem, and its technical problem is to rationally suppress a dynamic overload in an initial operation state of an electric compressor, and to easily perform a cooling request. An object of the present invention is to provide a vehicle air conditioner capable of improving the followability to the vehicle.

[0011]

According to the present invention, in a vehicle air conditioner including a refrigerant circuit including a condenser, a tank that stores cooling water and a high pressure side pressure in the refrigerant circuit are detected, and A vehicular air conditioner equipped with a pressure detection device that outputs a supply instruction signal when the high-pressure side pressure exceeds a predetermined value, and a water supply device that supplies cooling water to the outer surface of the condenser in accordance with the supply instruction signal is obtained. .

Further, according to the present invention, in the above vehicle air conditioner, the refrigerant circuit includes an evaporator, and the vehicle is provided with a condensed water collecting means for guiding condensed water obtained from the evaporator to the tank as cooling water. An air conditioner is obtained.

[0013]

【Example】

 Hereinafter, the vehicle air conditioner of the present invention will be described in detail with reference to the accompanying drawings. FIG. 1 shows a basic configuration of a vehicle air conditioner according to an embodiment of the present invention. In FIG. 1, the same parts as those shown in FIG. 3 are designated by the same reference numerals and the description thereof will be omitted.

This vehicle air conditioner detects the high pressure side pressure in the tank 8 that stores the cooling water outside the refrigerant circuit 1 and the refrigerant circuit 1, and supplies a supply instruction when the high pressure side pressure exceeds a predetermined value. A pressure detection device 9 that outputs a signal, and an electric pump 10 that draws cooling water from the tank 8 and supplies it to a nozzle 11 arranged near the condenser 4 in accordance with a supply instruction signal from the pressure detection device 9. It has and. The cooling water is jetted from the nozzle 11 toward the condenser 4. The electric pump 10 and the nozzle 11 work as a water supply device that supplies cooling water to the outer surface of the condenser 4.

Further, a hopper 12 is provided near the lower portion of the evaporator 6 so as to accommodate the lower portion. A pipe is connected to the hopper 12, and the pipe is connected to the tank 8. That is, the hopper 12 with a pipe functions as a condensed water collecting means for guiding the condensed water obtained from the evaporator 6 to the tank 8 as cooling water.

The vehicle air conditioner having such a configuration detects the high-pressure side pressure of the refrigerant circuit 1 by the pressure detection device 9, and when this high-pressure side pressure causes a dynamic overload on the electric compressor 3, Since the electric pump 10 is operated to inject the cooling water into the condenser 4 to remove the latent heat of vaporization from the condenser 4, the heat dissipation capacity of the condenser 4 can be temporarily increased when necessary. As a result, the vehicle air conditioner stabilizes the pressure on the high-pressure side of the refrigerant circuit 1 and stabilizes the electric compressor 3 even when the transient heat load in the initial state of operation during cooling such as midsummer is large. Dynamic overload is suppressed and the desired cooling capacity is obtained.

FIG. 2 is a characteristic diagram showing the magnitude P (vertical axis) of the high-pressure side pressure in the initial operation state of the electric compressor 3 according to the vehicle air conditioner in relation to the elapsed time t (horizontal axis). It is a figure. According to this characteristic curve C2, the peak of the magnitude P of the high pressure side pressure that appears at the elapsed time Δt 'is approximately the same as the magnitude P _{R of the} reference pressure. This suggests that in the case of this vehicle air conditioner, the dynamic overload does not occur in the electric compressor 3.

[0018]

[Effect of device]

 As described above, according to the present invention, it is possible to rationally suppress the dynamic overload in the initial operation state of the electric compressor without increasing the driving force of the motor or decreasing the rotation speed to increase the torque. In addition, a vehicle air conditioner that can easily improve the ability to follow the cooling demand is realized. Further, in the case of this air conditioner, since it is not necessary to use a large condenser and the air conditioner itself can be configured to be small and lightweight, it has an advantage of being excellent in wearability. Furthermore, in the case of this air conditioner, since the condensed water obtained from the evaporator is recycled as cooling water, it is not necessary to supply water to the tank frequently.

[Brief description of drawings]

FIG. 1 shows a basic configuration of a vehicle air conditioner according to an embodiment of the present invention.

2 is a characteristic diagram showing the magnitude P of the high-pressure side pressure in the initial operation state of the electric compressor provided in the vehicle air conditioner shown in FIG. 1 in relation to the elapsed time t.

FIG. 3 shows the basic configuration of a conventional vehicle air conditioner.

4 is a characteristic diagram showing the magnitude P of the high-pressure side pressure in the initial state of operation of the electric compressor provided in the vehicle air conditioner shown in FIG. 3 in relation to the elapsed time t.

[Explanation of symbols]

 1 Refrigerant Circuit 3 Electric Compressor 4 Condenser 5 Expansion Valve 6 Evaporator 7 Receiver Dryer 8 Tank 9 Pressure Detecting Device 10 Electric Pump 11 Nozzle 12 Hopper

Claims (2)

[Scope of utility model registration request] 1. A vehicle air-conditioning system comprising a refrigerant circuit including a condenser, which detects a high-pressure side pressure in a tank that stores cooling water and the high-pressure side pressure in the refrigerant circuit, and supplies when the high-pressure side pressure exceeds a predetermined value. A vehicle air conditioner comprising: a pressure detection device that outputs an instruction signal; and a water supply device that supplies the cooling water to the outer surface of the condenser according to the supply instruction signal. 2. The vehicle air conditioner according to claim 1, wherein the refrigerant circuit includes an evaporator, and the condensed water collecting means for guiding condensed water obtained from the evaporator to the tank as the cooling water is provided. A vehicle air conditioner characterized by the above.