JPH1071846A - Air conditioner for automobile - Google Patents

Abstract

PROBLEM TO BE SOLVED: To restrain generation of an offensive smell without deteriorating cooling capacity by arranging an air blowing control means so that an air quantity passing through the vicinity of one side end part of an evaporator becomes larger than an air quantity passing through the vicinity of the other side end part. SOLUTION: A guide plate 3 is arranged in a central part of an evaporator 2, and a part of air from a fan 1 is introduced to the upstream by changing the blowing air direction along the guide plate 3. Therefore, both of air sent from the fan 1 out of relation to the guide plate 3 and air introduced by the guide plate 3, contact with the upstream vicinity, and air of a quantity by subtracting air introduced to the upstream by the guide plate 3 from air sent out of relation to the guide plate 3, passes through the downstream. Therefore, it follows that a refrigerant whose upstream temperature is low exchanges heat with a larger quantity of air, a comparatively large temperature rise is caused according to this, and a downstream refrigerant is restrained small. A blowoff temperature of air is equalized, and the deterioration of cooling capacity and generation of an offensive small can be prevented.

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. 4 exemplifies 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 toward a cooling unit 50 having an evaporator 2. The conventional intake unit 30 has a cooling unit 50 such that the fan 1 contacts the surface of the evaporator 2 as uniformly as possible with the wind.
The amount of air actually blown is slightly larger at the center of the evaporator, 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. 5 illustrates the configuration of the evaporator 2 and the flow of the refrigerant passing through the inside thereof. 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. 6 is a view of the air conditioner shown in FIG. 5 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. 5 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 refrigerant inlet 21 than to the central portion, rather than to the portion downstream of the refrigerant closer to the refrigerant outlet 22 than the central portion (hereinafter also referred to as the downstream side). Upstream (hereinafter also referred to as upstream)
And lower. 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. 7 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 unpleasant odor generated in 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 the automotive air conditioner, the air blown from the blower means such 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. Is provided.

[0016] With this configuration, the taken-in air is brought into contact with one side end provided with the refrigerant inflow port with more air than the amount of air passing near the other side end. By adjusting the heat exchange between the evaporator and the air, the temperature of the evaporator can be made uniform. Therefore, icing on the surface of the evaporator can be prevented even if the temperature of any position of the evaporator is detected.

According to a second aspect of the present invention, there is provided an air conditioner for an automobile,
The blower control means is constituted by a guide plate that guides a part of the air blown from the blower means toward one measuring end portion provided with the refrigerant inlet of the evaporator. It is assumed that.

With this configuration, the evaporator is brought into contact with one of the side ends where the refrigerant inlet is provided by the guide plate, so that a larger amount of air passes through the other side end than the other end. The heat exchange between the air and the air can be adjusted to make the temperature of the evaporator uniform. Therefore, icing on the surface of the evaporator can be prevented even if the temperature of any position of the evaporator is detected.

According to a third aspect of the present invention, there is provided an air conditioner for an automobile,
The blower control unit is characterized by comprising a reflector plate that reflects a part of the air blown from the blower unit toward one side end of the evaporator where the refrigerant inlet is provided. It is assumed that.

With this configuration, the evaporator is brought into contact with a portion near one side end where the refrigerant inlet is provided by the reflector and more air than the amount of air passing near the other side end. The heat exchange between the air and the air can be adjusted to make the temperature of the evaporator uniform. Therefore, icing on the surface of the evaporator can be prevented even if the temperature of any position of the evaporator is detected.

[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 mouth is referred to as intake unit mouth 35. The intake unit 30 has an inside / outside air switching unit and a fan scroll unit. The inside / outside air switching unit has intakes 10 and 11 and an intake door 8. 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.

In the air conditioner for a vehicle according to the present embodiment, the fan 1 rotates in a fixed direction as in the conventional configuration.
The air taken in from the outside air inlet 10 and the inside air inlet 11 is sent to the evaporator 2 of the cooling unit 50. 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.

At the center of the evaporator 2 according to the present embodiment, a guide plate 3 as an air blowing control means as shown in the figure is provided.
This embodiment is unique to the present embodiment in that a larger amount of air blown by the fan 1 is guided to the upstream side than the downstream side of the refrigerant flowing through the evaporator 2.

The guide plate 3 is a rectangular plate fixed to the inner wall of the cooling unit 50,
The angle formed with the plane is constant. Part of the air that should have been sent to the downstream side from the fan 1 changes the direction of the air blow along the guide plate 3 and is guided to the upstream side of the evaporator 2. Therefore, both the air sent from the fan 1 and the air guided by the guide plate 3 come into contact with the vicinity of the upstream side of the evaporator 2 irrespective of the guide plate. On the other hand, on the downstream side of the evaporator 2, air passes by an amount obtained by subtracting air guided by the guide plate 3 to the upstream side from air sent from the fan 1 irrespective of the guide plate 3.

Therefore, the refrigerant having a low temperature and a high cooling capacity on the upstream side of the evaporator 2 exchanges heat with a larger amount of air. Therefore, a relatively large temperature rise occurs in the low-temperature refrigerant upstream of the evaporator 2 accordingly. On the other hand, since the refrigerant on the downstream side of the evaporator 2 having a relatively low temperature and a low cooling capacity exchanges heat with a smaller amount of air, the rise in the temperature of the refrigerant is also suppressed to a relatively small value. 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 uniform.

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.

The angle, area, dimensions and the like of the guide plate 3 of the present embodiment are appropriately designed according to 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. Can be.

As described above, in this embodiment, the temperature of the evaporator can be made uniform by adjusting the amount of air to be passed depending on the position of the evaporator by using the guide plate 3 located in front of the evaporator. 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, the thermistor switch can perform a predetermined function regardless of the position of the temperature sensor, and the mounting position of the temperature sensor can be easily determined. Become.

Second Embodiment FIG. 2 is a diagram illustrating the 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, this embodiment is different from the above-described first embodiment in that the setting position of the guide plate is modified.

In the vehicle air conditioner of the present embodiment, intake unit 30 and cooling unit 50
A guide plate 4 as shown in the drawing is provided on the inner wall of the fan scroll 16 at the boundary between the fan scroll 16 and the air blown by the sirocco fan 1 so as to preferentially contact the upstream side of the evaporator 2 with respect to the downstream side. This is a configuration unique to the present embodiment. The guide plate 4 is also a rectangular plate fixed to the inner wall, and the angle formed with the inner wall is constant. Part of the air that should have been sent from the fan 1 to the downstream side of the evaporator 2 changes the direction of the air blow along the guide plate 4 and is guided to the upstream side of the evaporator 2. Therefore, a large amount of air passes through the upstream side of the evaporator 2 and a relatively small amount of air passes through the downstream side, and acts to make the temperature of the evaporator 2 uniform.

Also in the guide plate 4 of the present embodiment, the angle, dimensions and area are appropriately designed according to the amount of air to be distributed to the upstream or downstream portion of the evaporator 2 and the temperature distribution of the evaporator 2. It is possible to

As described above, in the present embodiment, the guide plate 4 positioned at the boundary between the intake unit and the cooling unit is used to adjust the amount of air to be passed depending on the position of the evaporator, thereby enabling the evaporator to operate. It is possible to make the temperature uniform. 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.

Since the blowout temperature of the evaporator is uniform, the thermistor switch can perform a predetermined function regardless of the position of the temperature sensor, and the mounting position of the temperature sensor can be easily determined. Become.

Third Embodiment FIG. 3 is a diagram illustrating the configuration of an air conditioner for a vehicle according to a third embodiment. 1 and 2 in the drawings, the same components are denoted by the same reference numerals. In this embodiment, the basic configuration and the temperature distribution of the evaporator 2 are the same as those of the first and second embodiments. However, fan 1
A reflecting plate 5 is provided between the evaporator 2 and the evaporator 2 so as to reflect the air blown by the fan 1 so that the air passes through the evaporator 2 more preferentially on the downstream side than on the upstream side. This is a configuration unique to the present embodiment.

The reflecting plate 5 is a rectangular plate provided on the bottom of the fan scroll 16 and has a constant angle with the bottom. Part of the air sent from the fan 1 to the evaporator 2 is reflected by the reflector 5 and guided to the upstream side of the evaporator 2. Therefore, a larger amount of air passes through the upstream side of the evaporator 2 and a relatively small amount of air passes through the downstream side, thereby making the temperature of the evaporator 2 uniform.

Also in the reflecting plate 5 of the present embodiment, the angle, dimensions and area with respect to the evaporator are appropriately determined according to the amount of air to be distributed to the upstream or downstream portion of the evaporator 2 and the temperature distribution of the evaporator 2. design,
It is possible to change.

As described above, in this embodiment, the temperature of the evaporator is controlled by adjusting the amount of air to be passed depending on the position of the evaporator by the reflector 5 provided between the fan and the evaporator and at the bottom of the fan scroll. Can be made uniform. 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 position of the temperature sensor, and the mounting position of the temperature sensor can be easily determined. Become.

[0040]

According to the first aspect of the present invention, the temperature of the evaporator is made uniform by passing more air in the evaporator on the upstream side of the refrigerant flow than on the downstream side. 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.

According to a second aspect of the present invention, there is provided an air conditioner for an automobile,
By using a guide plate that guides air toward the upstream side of the evaporator, the flow of air is efficiently and easily controlled to prevent icing on the surface of the evaporator, and to suppress a decrease in cooling capacity and the generation of an odor. be able to.

According to a third aspect of the present invention, there is provided an air conditioner for an automobile.
By using a reflector that reflects light toward the upstream side of the evaporator, it is possible to efficiently and easily control the flow of air to prevent icing on the evaporator surface, and to suppress a decrease in cooling capacity and generation of an unusual odor. it can.

[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 second embodiment of the present invention.

FIG. 3 is a diagram illustrating a configuration of an automotive air conditioner according to a third embodiment of the present invention.

FIG. 4 is a diagram illustrating a configuration of a conventional automotive air conditioner.

FIG. 5 is a perspective view illustrating the flow of the refrigerant in the evaporator.

FIG. 6 is a diagram illustrating a configuration of a conventional automotive air conditioner viewed from above.

FIG. 7 is a graph illustrating the relationship between the blowing temperature and the odor intensity.

[Explanation of symbols]

1 ... fan, 2 ... evaporator, 3, 4 ... guide plate,
5: Reflector, 16: Fan scroll, 30: Intake unit, 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 built in, and has flowed down from the intake unit. A cooling unit (50) for cooling air, wherein the amount of air passing near one side end of the evaporator (2) is equal to the amount of air passing near the other side end. An air conditioner for an automobile, comprising: a blower control unit (3, 4, 5) for guiding air blown from the blower unit (1) so as to increase the number of the air conditioners. 2. The air blowing control means transfers a part of the air blown from the air blowing means (1) to one side end of the evaporator (2) where the refrigerant inlet (21) is provided. The air conditioner for a vehicle according to claim 1, further comprising a guide plate (3, 4) that guides toward the vehicle. 3. The air blowing control means transfers a part of the air blown from the air blowing means (1) to one side end of the evaporator (2) where the refrigerant inlet (21) is provided. The air conditioner for a vehicle according to claim 1, further comprising a reflector (5) for reflecting light toward the vehicle.