JP4031573B2 - Air conditioner for vehicles - Google Patents

Description

[0001]
BACKGROUND OF THE INVENTION
The present invention relates to an air conditioner for a vehicle that is installed in a vehicle such as a bus and performs cooling in the passenger compartment, and more particularly to an air conditioner for a vehicle that includes a capacitor unit on a roof.
[0002]
[Prior art]
As a vehicle air conditioner equipped on a bus or the like, a sub-engine system mainly used for a large sightseeing bus and a direct connection system mainly used for a route bus or a small bus are known.
[0003]
The sub-engine system is equipped with an engine (sub-engine) dedicated to the air conditioner separately from the vehicle engine (main engine). A refrigerant compressor is used by using the driving power of the sub-engine. Is configured to drive.
In the case of this sub-engine system, main devices such as the sub-engine and the compressor are unitized and are usually installed in a space below the passenger compartment at the center of the vehicle body.
[0004]
On the other hand, a directly-coupled vehicle air conditioner obtains a driving force from a traveling engine of a vehicle to a refrigerant compressor or the like, similarly to a passenger car or the like.
In the case of a small bus, the compressor may be installed in the vicinity of the engine at the front of the vehicle body, the condenser unit may be installed below the vehicle compartment at the center of the vehicle body, and the evaporator unit may be installed at the upper part (ceiling) of the vehicle compartment at the rear of the vehicle body. Many.
[0005]
On the other hand, in the case of a route bus, the compressor is often installed near the engine at the rear of the vehicle body, and the evaporator unit and the capacitor unit are often installed on the roof of the vehicle body.
In particular, recently, there has been an increasing need to install an evaporator unit and a capacitor unit on the roof because the vehicle tends to be lowered to facilitate getting on and off of elderly people and physically handicapped people.
[0006]
As shown in FIG. 6, the capacitor unit includes six capacitor fans 1, which are arranged at intervals from each other, three in the left and right directions in the traveling direction of the vehicle (outlined arrows). 1 and a capacitor 2 disposed in the center in the left-right direction so as to be sandwiched between them.
[0007]
As shown in FIG. 9, the capacitor 2 includes a plurality of fins 3 arranged at slight intervals along the left-right direction, and a plurality (n) of tubes 4 inserted so as to be orthogonal to the fins 3. And.
The tube 4 is a U-shaped pipe for refrigerant circulation, and the open ends thereof are the refrigerant inlet and outlet.
[0008]
Further, the inlet of each tube 4 is connected to a refrigerant pipe extending from the compressor to the condenser unit, and the outlet of each tube 4 is connected to a refrigerant pipe extending from the condenser unit to the evaporator unit.
With the above configuration, the refrigerant sent from the compressor to the condenser unit through the refrigerant pipe flows in parallel in the condenser 2 which is cut into n pieces by the chain line in FIG.
[0009]
Then, the gas refrigerant sent from the compressor to the condenser unit is sucked by the condenser fan 1 until it is divided on the upstream side of the condenser 2, circulates in each tube 4, and merges on the outlet side. It is condensed by exchanging heat with the outside air (see FIG. 7).
The condensed liquid refrigerant is sent to the evaporator unit through the refrigerant pipe and used for cooling the indoor air.
[0010]
[Problems to be solved by the invention]
By the way, as shown by the solid line in FIG. 7, the outside air supplied to the heat exchange with the capacitor 2 passes through the capacitor 2 from above the capacitor 2 by the rotation of the capacitor fan 1, It is designed to be discharged to the outside.
[0011]
However, the wind speed distribution of the outside air passing through the condenser 2 is as shown in FIG.
In FIG. 8, the X axis indicates the distance from the center of the capacitor 2 in the width direction (left and right direction), the Y axis indicates the wind speed of the outside air passing through the capacitor 2, and x1 and x2 indicate the left end and the right end of the capacitor 2, respectively. ing.
[0012]
As is apparent from this figure, in the configuration of the conventional capacitor unit, the wind speed distribution of the outside air passing through the capacitor 2 gradually weakens as the distance from the capacitor fan 1 increases, so that heat exchange between the gas refrigerant and the outside air is performed for each path. It is not performed evenly, and the refrigerant temperature at the outlet side of each tube 4 varies.
As a result, there is a problem that the condensation efficiency is lowered and the original cooling capacity cannot be fully exhibited.
[0013]
The present invention has been made in view of the above circumstances, and its object is to equalize the amount of heat exchange between the gas refrigerant and the outside air performed for each pass and improve the condensation efficiency of the gas refrigerant in the capacitor unit. There is to make it.
[0014]
[Means for Solving the Problems]
In order to solve the above problems, the present invention adopts the following configuration.
That is, a compressor that compresses a gaseous refrigerant, a capacitor unit that exchanges heat between the gas refrigerant supplied from the compressor and the outside air, a liquid refrigerant supplied from the capacitor unit, and a vehicle interior And an evaporator unit that exchanges heat with air, and the condenser unit is installed on a roof of a vehicle body. The condenser unit circulates the gas refrigerant. A capacitor having a plurality of tubes, and a capacitor fan disposed so as to be sandwiched between the capacitors , wherein the outside air passes from the center of the upper surface of the capacitor unit through the capacitor from top to bottom. after, when distributed as discharged from both ends of the capacitor unit through the condenser fan Tomo The longitudinal direction of the respective tube, and is characterized in that it is arranged along a direction in which said condenser fan and said condenser are facing.
[0015]
According to this vehicle air conditioner, the path is cut along the direction of the change in the wind speed of the outside air passing through the condenser. Therefore, the amount of heat exchange between the gas refrigerant and the outside air performed for each path, that is, each tube is The amount of heat exchange between the flowing gas refrigerant and the outside air is uniform in all tubes.
[0016]
DETAILED DESCRIPTION OF THE INVENTION
Hereinafter, an embodiment of the present invention will be described with reference to FIGS.
In these drawings, reference numeral 10 is a refrigerant system, 11 is a compressor, 12 is a condenser unit, 13 is an expansion valve, 14 is an evaporator unit, 15 is a condenser fan, 16 is a condenser, 17 is a fin, 18 is a tube, and E is An engine for traveling is shown.
[0017]
As shown in FIG. 5, the refrigerant system 10 has two left and right lines, and two compressors 11 are installed at the rear of the vehicle body adjacent to the traveling engine E and driven by the belt 11 a. It has become.
Further, as shown in FIG. 4, the capacitor unit 12 and the evaporator unit 14 are both installed on the roof of the vehicle body.
[0018]
As shown in FIG. 2, the capacitor unit 12 includes six capacitor fans 15 that are arranged at intervals from each other, three in the left and right directions in the traveling direction of the vehicle (open arrows), and these capacitor fans. 15 and a capacitor 16 disposed at the center in the left-right direction so as to be sandwiched between the two.
[0019]
As shown in FIG. 1, the capacitor 16 includes a plurality of fins 17 arranged in parallel with a slight gap in the left-right direction (a direction orthogonal to the vehicle traveling direction) and a plurality (n pieces) of the fins 17 inserted therethrough. ) Tube 18.
The tube 18 is a U-shaped pipe for refrigerant circulation, and its open ends serve as refrigerant inlet and outlet.
[0020]
Further, the inlet of each tube 18 is connected to a refrigerant pipe 21 extending from the compressor 11 to the condenser unit 12, and the outlet of each tube 18 is connected to a refrigerant pipe 22 extending from the condenser unit 12 to the evaporator unit 14. Has been.
[0021]
With the above configuration, as shown by the chain line in FIG. 2, the capacitor unit 12 is divided into paths along the direction (left-right direction) in which the capacitor fan 15 and the capacitor 16 face each other. Will flow in parallel.
[0022]
Next, the operation of the refrigerant system 10 will be described.
During the cooling operation, the compressor 11 is driven through the belt 11a using the engine E as a drive source, and compresses the low-temperature and low-pressure gas refrigerant.
Thus, the gas refrigerant which became high temperature high pressure is sent to the capacitor | condenser unit 12, and heat-exchanges with external air.
[0023]
In the condenser unit 12, the gas refrigerant sent from the compressor 11 is divided into the tubes 18 on the upstream side of the condenser 16.
These divided gas refrigerants are cooled and condensed by the outside air sucked by the condenser fan 15 until they merge again at the outlet side of each tube 18.
[0024]
As shown in FIG. 3, the outside air that cools the gas refrigerant passes through the condenser 16 from the center of the upper surface of the capacitor unit 12 from the top to the bottom, then makes a U-turn, passes through the condenser fan 15, and passes through the upper surface of the capacitor unit 12. Since the air is discharged from both ends, the wind speed distribution of the outside air passing through the condenser 16 gradually becomes weaker as the distance from the condenser fan 15 increases.
[0025]
Therefore, the amount of heat exchange between the gas refrigerant flowing through the tube 18 and the outside air is small in the central portion in the left-right direction of the capacitor 16 and gradually increases toward both ends. In the capacitor unit 12 of the present embodiment, Since the longitudinal direction of each tube 18 is arranged in parallel along the direction of change in the wind speed of the outside air passing through the condenser 16, the heat exchange amount for each tube 18 is equal, and therefore the gas refrigerant is equally distributed in each path. Is cooled, and the condenser outlet temperature becomes uniform.
[0026]
The liquid refrigerant condensed in this way is sent to the receiver 23 to separate the gas and liquid, and further led to the expansion valve 13 through the dryer 24.
The high-temperature and high-pressure liquid refrigerant decompressed and expanded by the expansion valve 13 is sent to the evaporator unit 14 as a low-temperature and low-pressure liquid refrigerant, and is sucked into the blower 25 and exchanges heat with the air in the passenger compartment passing through the evaporator 26. Cool and dehumidify the air.
[0027]
The refrigerant that has become a low-temperature and low-pressure gas refrigerant by this heat exchange returns to the compressor 11 and is compressed again, and the refrigeration cycle is configured by repeating such clockwise circulation (solid arrow in FIG. 5). Air conditioning in the passenger compartment is realized by the refrigeration cycle.
[0028]
As described above, according to the vehicle air conditioner of the present embodiment, the longitudinal direction of each tube 18 through which the gas refrigerant flows is arranged so as to be parallel to the direction in which the condenser fan 15 and the condenser 16 face each other. Therefore, the path is cut along the direction of the change in the wind speed of the outside air passing through the condenser 16.
[0029]
As a result, the amount of heat exchange between the gas refrigerant flowing through each tube 18 and the outside air is equalized in all the tubes 18, and the inconvenience that the heat exchange amount is different for each path and condensation is not performed efficiently is avoided. can do.
That is, the amount of heat exchange between the passes is equalized, the condensation efficiency is improved, and the original air conditioning capability can be fully utilized.
[0030]
In the present embodiment, the direct connection type vehicle air conditioner has been described. However, the present invention can also be applied to a sub engine type vehicle air conditioner.
That is, even in large buses such as sightseeing buses, in recent years, the capacitor unit 12 may be installed on the roof together with the evaporator unit 14 in order to secure a wider underfloor trunk room. An air conditioning apparatus can be applied.
[0031]
【The invention's effect】
As is clear from the above description, according to the vehicle air conditioner of the present invention, the path is cut along the direction of change in the wind speed of the outside air passing through the condenser. The amount of heat exchange becomes uniform, and the condensation efficiency can be improved.
Therefore, it is possible to fully demonstrate the original air conditioning capability, and a comfortable air conditioning feeling can be obtained in the passenger compartment.
[Brief description of the drawings]
FIG. 1 is a perspective view showing a main part (capacitor unit) of an embodiment of a vehicle air conditioner according to the present invention.
FIG. 2 is a plan view schematically showing the capacitor unit shown in FIG.
FIG. 3 is a cross-sectional view taken along line AA in FIG.
4 is a perspective view showing a state in which the vehicle air conditioner including the capacitor unit shown in FIG. 1 is mounted on a route bus. FIG.
FIG. 5 is a refrigerant circuit diagram of the vehicle air conditioner shown in FIG.
FIG. 6 is a plan view schematically showing a conventional capacitor unit.
7 is a cross-sectional view taken along line BB in FIG.
FIG. 8 is a diagram showing a wind speed distribution of outside air passing through the capacitor shown in FIG. 6;
9 is an enlarged perspective view showing the capacitor shown in FIG. 6. FIG.
[Explanation of symbols]
11 Compressor 12 Capacitor unit 14 Evaporator unit 15 Capacitor fan 16 Capacitor 18 Tube

Claims (1)

A compressor that compresses a gaseous refrigerant, a condenser unit that exchanges heat between the gaseous refrigerant supplied from the compressor and the outside air, a liquid refrigerant supplied from the condenser unit, and air in the passenger compartment And an evaporator unit that exchanges heat between the condenser unit and a vehicle air conditioner that is installed on the roof of the vehicle body,
The capacitor unit includes a capacitor having a plurality of tubes through which the gas refrigerant is circulated, and a capacitor fan arranged at intervals so as to sandwich the capacitor, and the outside air is in the center of the upper surface of the capacitor unit. After passing through the capacitor from the top to the bottom from the portion, it is circulated so as to be discharged from both ends of the capacitor unit through the capacitor fan, and the longitudinal direction of each tube is the capacitor fan and the An air conditioner for a vehicle, wherein the air conditioner is arranged along a direction in which the capacitor faces.

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