JP2008273220A - Cooling device for vehicle - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a cooling device for a vehicle achieved in the reduction of an environment load. <P>SOLUTION: In the cooling device for the vehicle provided with a refrigeration circuit 21, an auxiliary radiator 40 is provided in a high pressure side route 24 having a radiator 26 of the refrigeration circuit. The heat exchange of a refrigerant of the high pressure side route and the cooled air of a cabin 32 is performed by the auxiliary radiator. Accordingly, the enthalpy of an inlet port of an expansion valve 23 becomes small, the ability of an evaporator 28 is enhanced, and the pressure of the high pressure side refrigerant is reduced. Thereby, the consumption power of a compressor 22 can be reduced. Since the reduction of the compression power and the enhancement of the cooling ability are simultaneously attained and a coefficient of performance is enhanced, the load to the vehicle is reduced and the reduction of the environment load can be expected. <P>COPYRIGHT: (C)2009,JPO&INPIT

Description

  The present invention relates to a cooling apparatus for a vehicle provided with a refrigeration circuit.

  A conventional vehicle cooling device will be described with reference to FIG. 3 shown in relation to a vehicle cabin. In FIG. 3, the refrigeration circuit 1 encloses a refrigerant, and a high pressure side path 4 and a low pressure side path 5 are formed by a compressor 2 for compressing the refrigerant and an expansion mechanism for expanding the refrigerant, that is, an expansion valve 3. It is divided. A radiator 6 such as a condenser is connected to the high-pressure side path 4. A radiator fan 7 is opposed to the radiator 6. An evaporator 8 is connected to the low-pressure side path 5. A blower fan 9 is opposed to the evaporator 8. A gas-liquid separator 11 is connected between the evaporator 8 and the compressor 2.

  The expansion valve 3 and the evaporator 8 are arranged corresponding to the cabin 12 of the vehicle. The cooling air cooled by the evaporator 8 is supplied to the cabin 12 by the blower fan 9 and circulates in the cabin 12. Thus, the cabin 12 is cooled. Further, the air in the cabin 12 is discharged to the outside through the vent duct 13.

  In order to reduce the environmental load, a vehicle cooling device is desired to reduce power consumption, improve cooling capacity, and improve the coefficient of performance by their synergistic action.

  However, in order to be able to supply cooling air to the cabin, it is necessary to discharge the cabin air to the outside. As a result, the air cooled by the evaporator is discarded outside from the cabin through the vent duct after cooling the cabin. Since the air thrown away from the cabin is generally at a lower temperature than the outside air, the vehicle air conditioner of FIG. 3 causes a waste of energy.

  3 cools the radiator by exposing it to the outside air, so that the refrigerant in the high-pressure side path (hereinafter, also referred to as “high-pressure side refrigerant”) may be used even if the capacity of the radiator is large. It cannot be cooled below the outside temperature. In particular, when carbon dioxide such as carbon dioxide exceeding the critical point is used as the refrigerant, the enthalpy of the expansion mechanism is dominated by the outside air temperature, and thus the capacity of the evaporator cannot be increased.

  Therefore, an object of the present invention is to provide a vehicle air conditioner that can reduce the environmental load.

  Another object of the present invention is to provide a vehicle cooling device that reduces waste of energy.

  Still another object of the present invention is to provide a vehicle cooling device with improved cooling capacity.

  Still another object of the present invention is to provide a vehicle cooling device that uses cooling air in a cabin to cool a refrigerant in a high-pressure side path of a refrigeration circuit.

  According to one aspect of the present invention, in a vehicle cooling device including a refrigeration circuit, an auxiliary radiator is provided in a high-pressure side path having a radiator of the refrigeration circuit, and the auxiliary radiator is configured to A vehicular cooling device characterized by exchanging heat with the cooled air in the passenger compartment is obtained.

  The auxiliary radiator may be connected between the expansion mechanism of the refrigeration circuit and the radiator.

  The auxiliary radiator may be connected between the compressor of the refrigeration circuit and the radiator.

  In the refrigeration circuit, a refrigerant that does not become a supercritical cycle may be used as the refrigerant.

  You may have a guide means which guides the air heat-exchanged with the said auxiliary radiator to the vicinity of the refrigerant | coolant exit part of the said radiator.

  The guide means has a heat radiating fan for accelerating the heat radiation of the radiator, and has means for sucking air using the negative pressure by the heat radiating fan to improve the air flow rate of the auxiliary radiator. It may be.

  The guide means may include means for improving the air flow rate of the auxiliary radiator by sucking air using a negative pressure generated by the traveling wind of the vehicle.

  The vehicle cooling device according to the present invention not only cools the radiator by the outside air but also further cools the high-pressure side refrigerant of the refrigeration circuit using the cooling air in the cabin, thereby reducing the refrigerant pressure and reducing the power consumption. Reduce. The pressure drop of the high-pressure side refrigerant is accompanied by an improvement in volumetric efficiency, and a reduction in power consumption and an increase in refrigerant circulation amount, that is, an improvement in cooling capacity can be achieved simultaneously. Furthermore, both the reduction in power consumption and the improvement in cooling capacity both increase the coefficient of performance and increase the efficiency of the refrigeration cycle, thus contributing to a reduction in vehicle fuel consumption. Therefore, it is possible to provide a vehicular cooling device that can reduce the environmental load.

  With reference to FIG. 1, the outline | summary of the cooling device for vehicles which concerns on embodiment of this invention is demonstrated. FIG. 1 is a schematic diagram showing a vehicle cooling device in relation to a cabin of a vehicle.

  In FIG. 1, the refrigeration circuit 21 encloses a refrigerant, and a high pressure side path 24 and a low pressure side path 25 are provided by a compressor 22 for compressing the refrigerant and an expansion mechanism 23 for expanding the refrigerant, that is, an expansion valve 23. It is divided. A radiator 26 such as a condenser and an auxiliary radiator 30 are connected to the high-pressure side path 24 on the downstream side. A heat radiating fan 27 for promoting heat dissipation is opposed to the heat radiator 26. An evaporator 28 is connected to the low pressure side path 25. A blower fan 29 is opposed to the evaporator 28. A gas-liquid separator 31 is connected between the evaporator 28 and the compressor 22.

  With reference to FIG. 2 in addition to FIG. 1, a specific structure of the vehicle cooling device of FIG. 1 will be described. FIG. 2 is a configuration explanatory view showing the vehicle cooling device in relation to the vehicle.

  The expansion valve 23, the evaporator 28, and the blower fan 29 are configured as an integral cooling unit and are disposed corresponding to the cabin 32 of the vehicle. The remaining part of the refrigeration circuit 21 is disposed in the engine room 34 of the vehicle. Reference numerals 35 and 36 denote sheets installed in the cabin 32.

  The auxiliary radiator 40 is connected between the expansion valve 23 and the radiator 26, and is connected to the refrigerant side pipe 41 for guiding the refrigerant, and the air side pipe covering the periphery of the refrigerant side pipe 41 from outside with a gap left therebetween. 42. That is, the auxiliary radiator 40 is a double tube. One end of the air-side pipe 42, that is, the first end 42 a is connected to a vent duct 33 that communicates with the cabin 32. The other end of the air-side pipe 42, that is, the second end portion 42 b opens in the vicinity of the refrigerant outlet portion of the radiator 26 in the engine room 34.

  The auxiliary radiator 40 can be made using a double pipe with an inner fin made of extruded material. Moreover, the refrigerant | coolant side piping 41 can also be made from a low fin tube. The air side pipe 42 is preferably a heat insulating hose.

  Next, the operation of the above-described vehicle cooling device will be described.

  When the compressor 22 of the refrigeration circuit 21 is driven by a vehicle engine, for example, high-temperature vaporized refrigerant compressed from the compressor 22 to the high-pressure side path 24 is discharged. The vaporized refrigerant is radiated from the radiator 26 through the refrigerant-side piping 41 of the auxiliary radiator 40 to be liquefied or cooled to a temperature that shows an optimum coefficient of performance even if it does not liquefy like carbon dioxide. Then, the expansion valve 23 is reached. The liquefied refrigerant reaches the evaporator 28 via the expansion valve 23 and evaporates, and becomes a low-temperature vaporized refrigerant and absorbs heat. Therefore, the air around the evaporator 28 is cooled. The vaporized refrigerant exiting the evaporator 28 is separated into liquid and gas by the gas-liquid separator 31. Only the vaporized refrigerant is sucked into the compressor 22 and compressed again.

  The cooling air cooled by the evaporator 28 is supplied to the cabin 32 by the blower fan 29 and circulates in the cabin 32. Thus, the cabin 32 is cooled. Further, the air in the cabin 32 flows into the vent duct 33 and is discharged to the vicinity of the refrigerant outlet portion of the radiator 26 through the air side pipe 42 of the auxiliary radiator 40. At this time, the air passing through the air-side pipe 42 of the auxiliary radiator 40 is air after the cabin 32 has been cooled, and thus is generally at a lower temperature than the outside air. Therefore, the air passing through the air side pipe 42 of the auxiliary radiator 40 is effectively heat exchanged with the refrigerant passing through the refrigerant side pipe 41.

  Here, the air side pipe 42 constitutes a guide means for guiding the air heat-exchanged by the auxiliary radiator 40 to the vicinity of the refrigerant outlet portion of the radiator 26. Although it can be expected that the air in the cabin 32 is supplied to the air side pipe 42 by the chamber pressure of the cabin 32, the air flow is sucked using the negative pressure by the heat radiating fan 27 to improve the air flow rate of the air side pipe 42. It is preferable to make it. Moreover, you may comprise so that air may be attracted | sucked using the negative pressure by the driving | running | working wind of a vehicle and the air flow rate of the air side piping 42 may be improved.

  A refrigerant such as carbon dioxide that becomes a supercritical cycle is desirable, but it can also be used in a cycle that does not become supercritical.

  In the vehicle cooling device described above, the air that has cooled the cabin 32 is not discharged as it is, but is led from the vent duct 33 to the auxiliary radiator 40 to further cool the high-pressure refrigerant flowing out of the radiator 26. Therefore, the enthalpy at the inlet of the expansion valve 23 is reduced, the capacity of the evaporator 28 is improved, and the pressure of the high-pressure side refrigerant is reduced. Therefore, the power consumption of the compressor 22 can be reduced.

  Further, since the compression ratio is lowered and the volume efficiency is improved, the amount of refrigerant circulation is increased and the cooling capacity is improved. Further, the reduction in the compression ratio reduces the discharge gas temperature and improves the life and reliability of the compressor, and also reduces the blow-by gas and contributes to the reduction of the power consumption of the compressor.

  Therefore, since the compressor power and the cooling capacity are improved at the same time and the coefficient of performance is improved, the load on the vehicle is reduced, and the reduction of the environmental load can be expected.

  The present invention can be applied as a cooling device for vehicles in general, and is particularly suitable as a cooling device for automobiles.

It is the schematic diagram which showed the cooling device for vehicles which concerns on embodiment of this invention by the relationship with the cabin of a vehicle. FIG. 2 is a configuration explanatory diagram illustrating the vehicle cooling device of FIG. 1 in relation to a vehicle. It is the schematic diagram which showed the conventional vehicle cooling device with the relationship with the cabin of the vehicle.

Explanation of symbols

DESCRIPTION OF SYMBOLS 21 Refrigeration circuit 22 Compressor 23 Expansion valve 24 High-pressure side path 25 Low-pressure side path 26 Radiator 27 Radiant fan 28 Evaporator 29 Blower fan 31 Gas-liquid separator 32 Cabin 33 Vent duct 34 Engine room 35, 36 Seat 40 Auxiliary radiator 41 Refrigerant-side piping 42 Air-side piping

Claims (7)

  In a vehicle air conditioner provided with a refrigeration circuit, an auxiliary radiator is provided in a high-pressure side path having a radiator of the refrigeration circuit, and the auxiliary radiator dissipates the refrigerant in the high-pressure side path and the cooled air in the passenger compartment. A vehicle air conditioner characterized by heat exchange.   The vehicle cooling device according to claim 1, wherein the auxiliary radiator is connected between an expansion mechanism of the refrigeration circuit and the radiator.   The vehicle cooling device according to claim 1, wherein the auxiliary radiator is connected between a compressor of the refrigeration circuit and the radiator.   The vehicle cooling device according to any one of claims 1 to 3, wherein the refrigeration circuit uses a refrigerant that does not become a supercritical cycle.   The vehicle cooling device according to any one of claims 1 to 4, further comprising guide means for guiding the air heat-exchanged by the auxiliary radiator to a vicinity of a refrigerant outlet portion of the radiator.   The guide means has a heat radiating fan for accelerating the heat radiation of the radiator, and has means for sucking air using the negative pressure by the heat radiating fan to improve the air flow rate of the auxiliary radiator. The vehicle cooling device according to claim 5, wherein   6. The vehicle cooling apparatus according to claim 5, wherein the guide means includes means for improving the air flow rate of the auxiliary radiator by sucking air using a negative pressure generated by a traveling wind of the vehicle.

Images