JPH1071823A - Air conditioner for automobile - Google Patents

Abstract

PROBLEM TO BE SOLVED: To uniformize the surface temperature distribution of an evaporator, and prevent partial freezing by connecting an intake unit and a cleaning unit to each other so that an air quantity passing through the vicinity of one side end part of the evaporator becomes larger than an air quantity passing through the vicinity of the other side end part. SOLUTION: In an air conditioner for an automobile having an intake unit 30 enclosing an evaporator 2 and a cleaning unit 50, the intake unit 30 is connected to the cleaning unit 50 by deflecting the air blowing center of blowing air of a fan 1 to the front face center of the evaporator 2, and air is sent more abundantly to the upstream side of the evaporator 2. Therefore, a refrigerant on the upstream side of the evaporator 2 generates a large temperature rise by exchanging heat with a larger number of air, on the one hand, an air quantity to exchange heat with a refrigerant on the downstream side of the evaporator 2 becomes small, and a temperature rise on the downstream side of the evaporator 2 is restrained small. Therefore, a temperature of the evaporator 2 is uniformized over the whole.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an air conditioner for a vehicle, and more particularly to an air conditioner for a vehicle which cools internal and external air sent by a fan by exchanging heat with a refrigerant passing through an evaporator.

[0002]

2. Description of the Related Art As is well known, an air conditioner for a vehicle includes an intake unit for taking air inside and outside the vehicle into the air conditioner, a cooling unit for cooling the taken air, and an air unit for taking the air. And a heater unit for warming the heater. FIG. 3 illustrates a conventional configuration of such a vehicle air conditioner, particularly from the intake unit to the cooling unit.

An outside air intake 10 for taking in air outside the vehicle compartment and an inside air intake 11 for taking in air inside the vehicle compartment are selectively opened and closed by an intake door 8. By this selective opening and closing, the ratio of the outside air and the inside air of the air taken into the intake unit 30 is adjusted. The taken inside air or outside air is sucked by a fan 1 which is, for example, a centrifugal multi-blade fan, and is blown to a cooling unit 50 having an evaporator 2 via an intake unit port 35 and a cooling unit port 36. In the conventional intake unit 30, the fan 1 is connected to the evaporator 2
(The surface of the evaporator 2 facing the fan 1 is also referred to as the front surface of the evaporator hereinafter.) The cooling unit 50 is connected to the cooling unit 50 so that the wind contacts as uniformly as possible. The amount of air actually blown is slightly larger at the center of the evaporator 2 and tends to decrease as the distance from the center increases.

[0004] The evaporator 2 is incorporated in a refrigeration cycle, and has a refrigerant passage formed therein for passing refrigerant circulated after being compressed by a compressor (not shown). FIG. 4 illustrates a configuration of the evaporator 2 and a flow of a refrigerant passing through the inside of the evaporator 2. The illustrated evaporator 2 has a laminated type and a two-pass flow path configuration. The refrigerant introduced into the evaporator 2 in a liquid state from the refrigerant inlet provided at one side end into the refrigerant passage exchanges heat with air in contact with the surface of the evaporator 2 and comes into contact with itself while being vaporized. The air is cooled and flows out from a refrigerant outlet provided at the other side end.

[0005] In order to reduce the temperature of the air more efficiently, the evaporator 2 is required to reduce its own temperature as much as possible to absorb a large amount of heat. However, when the surface of the evaporator 2 becomes 0 ° C. or less, moisture in the air passing around the fin freezes. The frozen ice adheres around the fins and hinders the flow of wind.

Accordingly, the evaporator 2 generally has a temperature sensor 25 to detect the temperature of air blown through the evaporator 2 (hereinafter, this temperature is also referred to as blowout temperature). When the blow-out temperature falls below a predetermined temperature, the temperature sensor 25 operates to activate the thermistor switch, thereby stopping the supply of current to the compressor that circulates the refrigerant.

[0007]

However, the temperature of the evaporator 2 is not always uniform along the flow direction of the refrigerant, and therefore, the thermistor switch may not be able to perform the above-mentioned predetermined function. Hereinafter, the reason why the temperature of the evaporator 2 becomes uneven will be described.

FIG. 5 is a view of the air conditioner shown in FIG. 3 as viewed from above, that is, from the direction indicated by the arrow in FIG. In the drawings, the same components are denoted by the same reference numerals. The arrows on the evaporator 2 show the flow of the refrigerant in FIG. 4 as viewed from above.

The refrigerant flowing from the inlet 21 exchanges heat with the air blown by the fan 1 in the evaporator 2,
It flows toward the outlet 22 while evaporating. Therefore, the refrigerant in the evaporator 2 that flows closer to the inlet 21 is closer to the liquid state and has a lower temperature, and the closer to the outlet 22, the higher the ratio of the gaseous refrigerant is, and the temperature is slightly higher. Therefore, such non-uniform temperature of the refrigerant is likely to occur in a configuration such as the illustrated evaporator 2 in which the refrigerant flows from one end to the other end. Due to the non-uniformity of the temperature of the refrigerant, the temperature of the evaporator 2 is also closer to the downstream side of the refrigerant than the central portion and closer to the refrigerant outlet 22 (hereinafter also referred to as the downstream side), and closer to the upstream of the refrigerant inlet 21 than the central portion. (Hereinafter also referred to as the upstream side). The temperature difference between the upstream side and the downstream side may be as high as about 10 ° C., and is generally considered to be acceptable if it is within 5 ° C.

If the temperature distribution of the evaporator 2 is not uniform along the flow direction of the refrigerant, the following problems occur depending on the position of the temperature sensor 25. That is, the temperature sensor 2
5 is disposed near the air outlet downstream of the evaporator 2, the thermistor switch is controlled while detecting the temperature of the air passing downstream of the evaporator 2,
Although icing at the downstream portion of the evaporator 2 can be prevented, icing may occur at the upstream side of the evaporator 2 because the air passing through the upstream portion of the evaporator 2 is excessively cooled.

On the other hand, when the temperature sensor 25 is disposed near the air outlet in the upstream portion of the evaporator 2, the thermistor switch is controlled while detecting the temperature of the air passing through the upstream portion of the evaporator 2 at the lowest temperature. Although icing in the evaporator 2 can be prevented, air passing through the downstream portion of the evaporator 2 cannot be sufficiently cooled, and there is a possibility that the cooling capacity may be reduced. Therefore, in order to prevent freezing in the evaporator 2 and prevent the cooling capacity from being lowered, the arrangement position of the temperature sensor 25 is important, and the operation of determining the position is complicated.

By the way, moisture in the air that comes into contact with the surface of the evaporator 2 is condensed, and the condensed water comes into contact with the air to dissolve the odor components contained in the air. When the temperature of the evaporator 2 drops to 0 ° C. or lower, condensed water freezes, and various odor components dissolved in the condensed water may precipitate due to a decrease in solubility, which may cause off-flavor generation.

FIG. 6 is a graph showing the relationship between the blow-out temperature of the evaporator 2, the odor intensity, which is the relative intensity of the odor generated by the evaporator 2, and the operating state of the thermistor switch at that time. In this graph, the vertical axis shows the blowing temperature and the odor intensity, and the horizontal axis shows time,
On the left side of b on the horizontal axis, the compressor is ON,
When the outlet temperature reaches a ° C., the temperature sensor 25 detects this and activates the thermistor switch to turn on the compressor.
FF. When the compressor is turned off, the circulation of the refrigerant stops, and the blowout temperature rises. From this figure, it can be seen that the odor intensity increases as the blowing temperature decreases, and decreases again as the blowing temperature increases.

The present invention has been made in view of such a point, and by making the temperature distribution on the surface of the evaporator uniform, it is possible to prevent partial icing of the evaporator and reduce the cooling capacity of the evaporator. It is an object of the present invention to provide an air conditioner for an automobile that suppresses generation of an unpleasant odor without lowering it.

[0015]

According to a first aspect of the present invention, there is provided an air conditioner for a vehicle, in which vehicle air or vehicle external air is selectively taken in and blown toward the downstream side by a blowing means incorporating the taken air. An intake unit and a cooling unit that has a built-in evaporator provided with a refrigerant inlet at one side end and a refrigerant outlet at the other side end, and cools air flowing down from the intake unit. In automotive air conditioners,
The intake unit and the cooling unit are connected so that the amount of air passing near one side end of the evaporator is larger than the amount of air passing near the other side end. Things.

With this configuration, the temperature of the evaporator can be adjusted and made uniform by allowing more air to pass toward the upstream side of the refrigerant of the evaporator and passing the air. Therefore, icing on the evaporator surface can be prevented regardless of the detection position of the blowout temperature of the evaporator.

According to a second aspect of the present invention, there is provided an air conditioner for an automobile,
The intake unit is connected to a cooling unit such that a front surface of the evaporator is disposed so as to be deflected from a center axis of air blown by the blower.

[0018] With this configuration, the temperature of the evaporator is adjusted by passing more air toward the upstream side of the refrigerant of the evaporator by the blowing means incorporated in the deflected cooling unit to adjust the temperature of the evaporator. Will be able to Therefore, icing on the evaporator surface can be prevented regardless of the detection position of the blowout temperature of the evaporator.

According to a third aspect of the present invention, in the air conditioner, the intake unit forms an angle such that more of the air blown by the blower passes through the one side end. It is characterized by being connected to a cooling unit.

With this configuration, the temperature of the evaporator is adjusted by passing more air toward the upstream side of the refrigerant of the evaporator from the blowing means incorporated in the cooling unit arranged at an angle, so as to adjust the temperature of the evaporator. , Can be made uniform. Therefore, icing on the evaporator surface can be prevented regardless of the detection position of the blowout temperature of the evaporator.

[0021]

BEST MODE FOR CARRYING OUT THE INVENTION

First Embodiment FIG. 1 is a diagram illustrating a configuration of an automotive air conditioner according to a first embodiment of the present invention. The air conditioner for a vehicle according to the present embodiment has intake unit 30 and cooling unit 50, and blows out air from intake unit 30 to the cooling unit at the boundary where intake unit 30 and cooling unit 50 are connected. The opening is referred to as an intake unit port 35, and the inlet of air to the cooling unit 50 is referred to as a cooling unit port 36. The intake unit 30 has an inside / outside air switching unit and a fan scroll unit.
0 and 11 are formed, and an intake door 8 is provided. The fan scroll unit includes a fan 1 and a fan scroll 16 that houses the fan 1.
The cooling unit 50 has the evaporator 2 for cooling the air blown from the fan 1. The temperature of the refrigerant flowing through the evaporator 2 near the upstream near the inflow port 21 is lower, and becomes higher as the refrigerant approaches the downstream near the outlet 22. Accordingly, the temperature of the surface of the evaporator 2 correspondingly becomes lower near the inflow port 21 and higher near the outflow port 22 of the illustrated evaporator 2.

The vehicle air conditioner according to the present embodiment
Intake unit 30 is located at inlet 21 of evaporator 2
The amount of air passing near the upstream side provided with
Is different from the conventional configuration in that it is connected to the cooling unit so that the amount of air passing through the side end portion provided with the cooling unit becomes larger. That is, intake unit 30 of the present embodiment deflects cooling unit 50 with respect to the center of the front surface of evaporator 2 so that the center of air blown by fan 1 is directed to the upstream side of evaporator 2 as shown in the figure. Is connected to Therefore, more air is blown to the upstream side of the evaporator 2. The refrigerant having a high cooling capacity on the upstream side of the evaporator 2 exchanges heat with a larger amount of air to generate a relatively large temperature rise. On the other hand, the amount of air that exchanges heat with the refrigerant on the downstream side of the evaporator 2 having a low cooling capacity becomes smaller, and the rise in the temperature on the downstream side of the evaporator 2 is accordingly suppressed relatively small. Therefore, the difference between the temperature on the upstream side and the temperature on the downstream side of the evaporator 2 becomes small, and the temperature of the evaporator 2 approaches the whole uniformly.

As the temperature of the evaporator 2 approaches uniformity, the temperature of the air blown through the evaporator 2 also becomes uniform. Therefore, irrespective of the position of the temperature sensor 25 on the evaporator 2, the thermistor switch exerts a predetermined function and can prevent freezing on the surface of the evaporator. By preventing icing, it is possible to prevent a decrease in cooling capacity and generation of an unusual odor due to the mechanism described above.

In the cooling unit 30 of the air conditioner for a vehicle according to the present embodiment, the center axis of the air blown by the fan 1 is biased so that more air is blown to the upstream side with respect to the front surface of the evaporator. It may be connected as long as it is connected, and can be appropriately designed depending on the amount of air to be distributed to the upstream and downstream sides of the evaporator 2 and the distribution of the cooling capacity of the refrigerant.

As described above, in the present embodiment, by arranging the fan of the cooling unit so as to be deflected with respect to the front surface of the evaporator, the amount of air to be passed can be adjusted to make the temperature of the evaporator uniform. It becomes possible. Therefore, partial icing on the evaporator surface can be prevented, and generation of an odor due to icing on the evaporator surface can also be prevented.

Further, since the blowout temperature of the evaporator becomes uniform and the thermistor switch can exert a predetermined function regardless of the arrangement of the temperature sensor, it is easy to determine the mounting position of the temperature sensor. become.

Second Embodiment FIG. 2 is a diagram illustrating a configuration of an air conditioner for a vehicle according to a second embodiment. This embodiment has substantially the same configuration as that of the first embodiment. In the drawing, the same components as those of FIG. 1 are denoted by the same reference numerals.
However, in the air conditioner of the present embodiment, the intake unit forms an angle with the cooling unit at an angle such that more of the air blown by the fan 1 passes near the upstream side of the evaporator 2. It differs from the first embodiment in that it is connected. That is, the intake unit port 35 and the cooling unit port 36 of the present embodiment are, as shown in FIG.
And the surface in contact with the cooling unit port 36 are connected at an angle A. Such a configuration allows more air out of the air blown by the fan 1,
The evaporator 2 is passed to the upstream side from the downstream side. Therefore, in the configuration of the present embodiment, similarly to the first embodiment, the upstream-side refrigerant exchanges heat with more air than the downstream-side refrigerant, and the upstream-side refrigerant has a relatively low temperature on the upstream side where the refrigerant temperature is relatively low. A large temperature rise occurs, and the temperature rise on the downstream side where the temperature of the refrigerant is relatively high is suppressed to be small, so that the temperatures of the two approaches uniform.

The cooling unit 30 of the air conditioner for a vehicle according to the present embodiment is only required to connect the fan 1 at an angle such that more air is blown to the upstream side of the evaporator. Angle is evaporator 2
Can be appropriately designed depending on the amount of air to be distributed to the upstream side and the downstream side, the distribution of the cooling capacity of the refrigerant, and the like.

As described above, in the present embodiment, the fan of the cooling unit is arranged at an angle to the front surface of the evaporator, thereby adjusting the amount of air to be passed to make the temperature of the evaporator uniform. Becomes possible. Therefore, partial icing on the evaporator surface can be prevented, and generation of an odor due to icing on the evaporator surface can also be prevented.

Further, since the blowout temperature of the evaporator becomes uniform, the thermistor switch can perform a predetermined function regardless of the arrangement of the temperature sensor, so that the mounting position of the temperature sensor can be easily determined. .

[0031]

According to the first aspect of the present invention, the temperature of the evaporator is reduced by connecting the intake unit and the cooling unit so that more air flows on the upstream side of the flow of the refrigerant than on the downstream side. Make it even. Therefore, the thermistor switch of the evaporator performs a predetermined function to prevent icing on the surface of the evaporator, thereby suppressing a reduction in cooling capacity and the generation of an odor.

An air conditioner for a vehicle according to claim 2 is
By connecting the intake unit and the cooling unit by deflecting the air blowing means to blow more air toward the upstream side of the evaporator, the air flow can be controlled efficiently and easily and the surface of the evaporator can be easily controlled. Freezing can be prevented, and a decrease in cooling capacity and generation of an unusual odor can be suppressed.

An air conditioner for a vehicle according to claim 3 is
By connecting the intake unit and the cooling unit at an angle so that the blowing means blows more air toward the upstream side of the evaporator, the air flow can be controlled efficiently and easily and the evaporator surface Can be prevented, and a decrease in cooling capacity and generation of an unpleasant odor can be suppressed.

[Brief description of the drawings]

FIG. 1 is a diagram illustrating a configuration of an automotive air conditioner according to a first embodiment of the present invention.

FIG. 2 is a diagram illustrating a configuration of a vehicle air conditioner according to a third embodiment of the present invention.

FIG. 3 is a diagram illustrating a configuration of a conventional automobile air conditioner.

FIG. 4 is a perspective view illustrating the flow of the refrigerant in the evaporator.

FIG. 5 is a diagram illustrating a configuration of a conventional automotive air conditioner viewed from above.

FIG. 6 is a graph illustrating the relationship between the blowing temperature and the odor intensity.

[Explanation of symbols]

DESCRIPTION OF SYMBOLS 1 ... Fan, 2 ... Evaporator, 16 ... Fan scroll, 25 ... Temperature sensor 30 ... Intake unit,
35 ... intake unit opening, 36 ... cooling unit opening, 50 ... cooling unit.

Claims (3)

[Claims] An intake unit (3) for selectively taking in air inside or outside of a vehicle and blowing air toward a downstream side by a blowing means (1) incorporating the taken-in air.
0), an evaporator (2) provided with a refrigerant inlet (21) at one side end and a refrigerant outlet (22) at the other side end is incorporated therein, and the intake unit (30)
Cooling unit (5) that cools air flowing down from
0), wherein the amount of air passing near one side end of the evaporator (2) is larger than the amount of air passing near the other side end. An air conditioner for a vehicle, wherein an intake unit (30) is connected to the cooling unit (50). 2. The cooling unit (50), wherein the intake unit (30) is arranged such that the front surface of the evaporator (2) is deflected from the center axis of the air blown by the blowing means (1). The vehicle air conditioner according to claim 1, wherein the air conditioner is connected. 3. The cooling unit is formed at an angle such that more of the air blown by the blowing means (1) passes near the one side end. The vehicle air conditioner according to claim 1, wherein the air conditioner is connected to (50).