JP2000097517A - Air conditioner - Google Patents

Abstract

PROBLEM TO BE SOLVED: To make the restraint of corrosion by sticking of a foreign matter compatible with the prevention of holdup of moisture in an evaporator. SOLUTION: A first coveting wall 7a coveting a face of an air flow upstream side of a tank part 22b is provided in a region of the air flow upstream side of the tank part 22b located in a lower part of an evaporator 2 in a case 7 accommodating the evaporator 2. By this a foreign matter such as dust contained in supplied air is prevented from directly sticking adjacent to a lower side tank part 22b of the evaporator 2. An opening part 7b is formed in the first covering wall 7a, and a second covering wall 7c having a size of the opening area of the opening part 7b or larger is arranged while a predetermined space is opened in the air flow upstream side of the first covering wall 7a. The moisture from the air flow upstream side is discharged to the downstream side through the opening part 7b.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an air conditioner having a built-in evaporator for cooling conditioned air.
It is suitable for automobiles.

[0002]

2. Description of the Related Art Conventionally, as shown in FIG. 6, in an automobile air conditioner or the like, an evaporator 2 is placed in a case 7 made of resin such that a heat exchange core portion 21 is oriented substantially vertically. The conditioned air is blown in a substantially horizontal direction while being housed, and passes between the fins of the core portion 21 of the aluminum evaporator 2.

[0003]

By the way, various foreign substances such as dust are mixed in the conditioned air blown to the evaporator 2. As shown in part A of FIG. 6, foreign matter accumulates. Then, an aluminum tube (not shown) or the like of the core portion 21 of the evaporator 2 may be corroded due to adhesion of foreign matter, and leakage of the refrigerant may occur.

Accordingly, the applicant of the present invention has disclosed in Japanese Patent Application No.
Japanese Patent No. 42635 proposes an air conditioner that solves the above problem. That is, in the case of the prior application, a covering wall for covering the tank portion is provided in a portion of the case accommodating the evaporator on the upstream side of the air flow of the tank portion located at the lower portion of the evaporator.

Accordingly, when foreign matters including various dusts mixed in the air blown into the case fall to the lower part of the evaporator and are going to accumulate, the foreign matters are deposited on the lower tank portion of the evaporator. Since the adhesion can be prevented by the covering wall, the foreign matter accumulates on the front side of the covering wall. As a result, it is possible to prevent a problem that a foreign substance directly adheres to a metal material such as aluminum constituting the lower tank portion of the evaporator and accelerates corrosion of the metal material.

However, when the above-mentioned prior application was evaluated in detail for practical problems, it was found that the lower tank portion of the evaporator was covered with a covering wall. If moisture is mixed in the air blown into the wall, the moisture remains on the front side of the coating wall and is not discharged. Therefore, it was found that the retained water rotted and caused mold and odor.

[0007] The present invention has been made in view of the above points,
An object of the present invention is to achieve both the suppression of corrosion due to the attachment of foreign matter in an evaporator and the prevention of retention of moisture.

[0008]

In order to achieve the above object, according to the first aspect of the present invention, a tank located at a lower portion of an evaporator (2) in a case (7) accommodating the evaporator (2). A first covering wall (7a) for covering the tank portion (22b) is disposed at a portion of the portion (22b) on the upstream side of the air flow, and the first covering wall (7a) is provided on the first covering wall (7a). ) To form an opening (7b) for discharging water from the upstream side to the downstream side of the air flow, and further, the first covering wall (7a).
A predetermined interval is provided on the upstream side of the air flow in the opening (7b).
A second covering wall (7c) having a size equal to or larger than the opening area is arranged.

According to this, foreign matters including various dusts mixed in the blowing air fall to the lower part of the evaporator (2),
When trying to deposit, the foreign matter adheres to the tank portion (22b) below the evaporator (2) by the first coating wall (7a).
Therefore, the foreign matter accumulates on the front side of the first covering wall (7a).

Thus, it is possible to reliably prevent a foreign substance from directly adhering to a metal material such as aluminum constituting the lower tank portion (22b) of the evaporator (2) and promoting corrosion of the metal material.

Further, an opening (7) is formed in the first covering wall (7a).
By forming b), moisture can be discharged from the upstream side of the first coating wall (7a) to the downstream side through the opening (7b), so that even if moisture enters the case (7). This can prevent the water from staying on the front side of the first covering wall (7a). As a result, it is possible to prevent the occurrence of mold and odor due to the retention of water.

Further, a second covering wall (7c) having a size larger than the opening area of the opening (7b) is arranged at a predetermined interval upstream of the first covering wall (7a) in the air flow. Thus, the second covering wall (7c) can surely prevent foreign matter from entering the opening (7b). Therefore, even if the opening (7b) for discharging moisture is added, the effect of preventing foreign matter from adhering to the tank (22b) below the evaporator (2) can be ensured.

As a result, it is possible to satisfactorily achieve both the suppression of corrosion due to the attachment of foreign matter in the evaporator (2) and the effect of preventing the retention of moisture.

Further, as in the second aspect of the present invention, the first
If the covering wall (7a) and the second covering wall (7c) are integrally molded with the case (7) with resin, both the covering walls (7a, 7c) can be easily molded at the time of molding the case (7), and the manufacturing cost is increased. This is advantageous for reduction.

The reference numerals in parentheses of the above means indicate the correspondence with the specific means described in the embodiment described later.

[0016]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS An embodiment of the present invention will be described below with reference to the drawings.

(First Embodiment) FIGS. 1 and 2 show a main part of a first embodiment according to the present invention. The ventilation system of the entire air conditioner for a vehicle to which the present invention is applied is the same as that of the prior application. First, the outline of the ventilation system will be described with reference to FIG. 3. As is well known, the blower 1 uses a centrifugal multi-blade fan, and the outside air ( Air outside the vehicle compartment) or inside air (air inside the vehicle compartment) is sucked into the suction port of the blower 1.

An evaporator 2 of a refrigeration cycle is arranged on the blow-off side of the blower 1. Here, the conditioned air blown by the blower 1 absorbs the latent heat of evaporation of the refrigerant and becomes cool air. A heater core 3 for heating air using hot water (engine cooling water) from an automobile engine as a heat source and an air mix door 4 for temperature control are arranged downstream of the evaporator 2 in the air.

By adjusting the position of the opening of the air mixing door 4, the ratio of the amount of hot air passing through the heater core 3 to the amount of cold air passing through the bypass passage 5 of the heater core 3 is adjusted, thereby reducing the temperature of the blown air. Control. The air controlled to the desired temperature in this manner is blown into the vehicle interior from a predetermined outlet 6 (such as a swage, a foot, or a defroster) selected by a mode switching door mechanism (not shown). Reference numeral 7 denotes a resin case that forms a passage for the air-conditioned air. In the case 7, a tray 8 for condensed water generated in the evaporator 2 projects downward from the bottom of the evaporator 2. Have been. A drain 9 for condensed water is opened at the lowest part of the receiving tray 8.

Next, the arrangement of the evaporator 2 as a main part of the present invention will be described in detail with reference to FIG.
As shown in the figure, the heat exchange core portion 21 is accommodated in the case 7 so as to be oriented substantially vertically, and cools the conditioned air flowing substantially horizontally. Here, the heat exchange core portion 21 of the evaporator 2 is composed of a number of tubes 2 having a flat section and arranged in parallel.
2 and a corrugated fin (fin member) 23 joined between the flat tubes 22. The flat tube 22 is disposed so that its longitudinal direction is substantially vertical.

The evaporator 2 is of a type generally referred to as a laminated type, and the flat tube 22 is formed by joining two aluminum thin metal plates in a centered manner. It is parallel to the air flow. After a predetermined number of the flat tubes 22 and the corrugated fins 23 are alternately stacked in the left-right direction in FIG. 1, the assembled state is held by an appropriate jig and brazed integrally in a furnace. Things.

Bowl-shaped protrusions are integrally formed on the upper and lower ends of the thin metal plate constituting the flat tube 22, and the distribution of the refrigerant to the flat tube 22 is performed by the bowl-shaped protrusions.
An upper tank portion 22a and a lower tank portion 22b for collecting the refrigerant from the flat tube 22 are configured. In FIG. 1, the lower tank portion 22b is connected to a first tank
Since it is located on the back side of the covering wall 7a in the drawing, it is not directly illustrated. In the example of FIG. 1, the upper tank portion 22a
The lower tank portion 22b and the lower tank portion 22b form a tank portion divided into an upstream side and a downstream side of the air flow, respectively.

The upper tank portion 22a and the lower tank portion 22b are provided with communication holes (not shown) for communicating the adjacent tank portions with each other. The communication holes allow the upper tank portion 22a and the lower tank portion 22a to communicate with each other. The passage of the tank portion 22b communicates in the left-right direction in FIG.

Reference numeral 24 denotes a refrigerant pipe joint. An inlet 24a through which a low-temperature and low-pressure gas-liquid two-phase refrigerant reduced in pressure by a temperature-type expansion valve (not shown) flows into the evaporator 2, and a gas which has been evaporated in the evaporator 2. An outlet 24b through which the refrigerant flows out toward the compressor suction side (not shown).

As shown in FIG. 1 and FIG.
A first coating wall 7a that covers the front side of the lower tank portion 22b of the evaporator 2 is formed at a position on the upstream side of the air flow of the lower tank portion 22b of the evaporator 2 so as to rise upward from the bottom surface of the case 7. ing. The height of the first covering wall 7a is set so as to cover the lower tank portion 22b. Specifically, the height of the first covering wall 7a is, for example, about 20 mm.

On the other hand, an opening 7b is formed in the first covering wall 7a from the bottom to the entire length in the height direction. The opening 7b is used to discharge moisture accumulated on the front side of the first covering wall 7a to the drain port 9 through the receiving tray 8 below the evaporator 2, and in FIG. Although only one location is provided at the center in the left-right direction, openings 7b may be provided at a plurality of locations in the left-right direction of the first covering wall 7a. The width W ₁ of the opening 7b is preferably more than 2mm in order to perform smoothly the discharge of water.

On the front side (upstream of the air) of the opening 7b, a second covering wall 7c for preventing foreign matter from entering the opening 7b is arranged at a predetermined interval L. The second covering wall 7c is the same height as the first covering wall 7a, having a width W ₁ or a width W ₂ of the opening 7b (in other words, having an open area more than the size of the opening 7b) It is formed as follows. Here, it is preferable that the distance L between the first coating wall 7a and the second coating wall 7c is also 2 mm or more in order to smoothly discharge water.

Since the case 7 is made of a resin such as polypropylene, the first covering wall 7a and the second
The covering wall 7c can be integrally formed with the case 7.

The operation of the present embodiment in the above configuration will be described. When the blower 1 is operated, the inside air or the outside air is blown by the blower 1 and the heat exchange core 21 of the evaporator 2 is heated.
Pass between the flat tube 22 and the corrugated fin 23. At this time, the air absorbs heat by the refrigerant flowing through the flat tube 22 and becomes cold air. Then, after the temperature of the cold air is adjusted by the opening of the air mix door 4,
The air blows out from a predetermined air outlet 6 into the vehicle interior.

On the other hand, foreign matters including various dusts (for example, cotton dust, insects, dead leaves, etc.) are mixed in the air blown to the evaporator 2. When passing between the corrugated fins 22 and the corrugated fins 23, it collides with the flat tube 22 and the corrugated fins 23, falls down, and tries to accumulate. At this time, since the front side of the lower tank portion 22b of the evaporator 2 is covered with the first coating wall 7a, the first coating prevents the foreign matter from adhering to the lower tank portion 22b of the evaporator 2. It can be blocked by the wall 7a.

As a result, the lower tank portion 22 of the evaporator 2
Foreign matter directly adheres to the aluminum material constituting b,
The problem of accelerating corrosion of the aluminum material can be reliably prevented.

Further, when the vehicle travels in rainy weather, snowfall, or the like, moisture enters the blast air in the case 7 and tends to accumulate on the front side of the first covering wall 7a. Since the opening 7b is formed in the first covering wall 7a over the entire length in the height direction from the bottom surface thereof,
Through the opening 7b, the water on the front surface of the first coating wall 7a can be smoothly discharged to the lower side of the evaporator 2. Therefore, it is possible to prevent the generation of mold and odor due to the retention of moisture on the front side of the first coating wall 7a.

[0033] Moreover, even if an opening 7b to the first covering wall 7a, the width W ₁ or more width W of the opening 7b
_Since the second covering wall 7c having the number 2 is arranged, the opening 7b can be covered by the second covering wall 7c, and therefore, the invasion of foreign matter into the opening 7b can be prevented by the second covering wall 7c.
Can be prevented.

The first coating wall 7a is connected to the lower tank 2
Only the front surface of the evaporator 2b is covered, and the heat exchange core portion 21 composed of the fins and the tube is not covered, so that the performance of the evaporator 2 does not deteriorate.

(Second Embodiment) Next, a second embodiment shown in FIGS. The specific configuration of the evaporator 2, the arrangement of the blower 1, and the like are different from those of the first embodiment.

The ventilation system of the air conditioner is mounted below the instrument panel in the vehicle cabin with the positional relationship shown in FIGS. In the case 7, an outside air inlet 30 for introducing air outside the vehicle compartment is provided at the left end of FIG.
And an inside air inlet 31 for introducing air in the vehicle cabin, and an inside / outside air switching door 32 for opening and closing these inlets 30, 31 is provided rotatably.

An evaporator 2 is installed downstream of the air inlets 30, 31 on the downstream side of the air. This evaporator 2 has a tank portion 22b disposed only on the lower side and no tank portion disposed on the upper side. Use something. The height of the first covering wall 7a is set so as to cover the lower tank portion 22b.

A blower 1 is installed downstream of the evaporator 2 in the air, and a heater core 3 and an air mixing door 4 are installed downstream of the blower 1 in the air. By operating the blower 1, air is introduced from one of the inlets 30 and 31, and the air passes through the evaporator 2, the blower 1 and the heater core 3 as shown by an arrow a, and then blows out into the vehicle interior. Is done.

Here, a specific design example of the first coating wall 7a and the second coating wall 7c will be described.
₁ = _20~30mm, a W ₂ = W ₁ + 10~20mm.

According to the second embodiment having the above-described structure, similarly to the first embodiment, the foreign matter contained in the introduced air is received by the first coating wall 7a and the second coating wall 7c. It is stored there. Accordingly, it is possible to reliably prevent a foreign substance from directly adhering to the aluminum material constituting the lower tank portion 22b of the evaporator 2 and promoting corrosion of the aluminum material.

In addition, water that has entered through the outside air inlet 30 and arrived at the front surface of the first covering wall 7a during rainy weather or the like flows into the opening 7b,
Furthermore, it flows to the drain port 9 side through the gap between the case 7 and the evaporator 2 and is discharged outside the vehicle compartment.

Further, when the second covering wall 7c is not provided, a part of the blown air easily flows under the evaporator 2 through the opening 7b. There is a possibility that water is leaked from the fitting portion of the case 7 by being blown off to the downstream side of the air flow.

However, according to the present embodiment, the opening 7b
The second coating wall 7c provided on the upstream side of the air flow suppresses the flow of air below the evaporator 2 through the opening 7b and reduces the flow velocity of the air flow flowing below the evaporator 2. To prevent the condensed water from scattering,
Can be prevented from leaking from the fitting portion.

(Other Embodiments) In the above-described embodiment, the first and second covering walls 7a and 7c are formed integrally with the case 7 with resin.
A and 7c may be formed solely of resin or the like and fixed to the case 7 by means such as adhesion.

In the above-described embodiment, the opening 7b is formed in the first covering wall 7a from the bottom surface to the entire length in the height direction. The opening 7b is for discharging moisture. , The water is almost completely removed by gravity from the first coating wall 7a.
The opening 7b may be formed only in a portion of the first covering wall 7a near the bottom, since it accumulates on the bottom side of the front surface.

Further, it goes without saying that the present invention can be similarly applied to an air conditioner for use other than for automobiles.

[Brief description of the drawings]

FIG. 1 is a perspective view of an evaporator installation site according to a first embodiment of the present invention.

FIG. 2 is an enlarged view of a portion B in FIG.

FIG. 3 is a schematic sectional view of a ventilation system of the automotive air conditioner according to the first embodiment of the present invention.

FIG. 4 is a schematic sectional view of a ventilation system of an automotive air conditioner according to a second embodiment of the present invention.

FIG. 5 is a plan sectional view of a main part of FIG. 5;

FIG. 6 is a sectional view of a main part of an evaporator installation site in a conventional apparatus.

[Explanation of symbols]

2 evaporator, 7 case, 7a first covering wall, 7b opening, 7c second covering wall, 21 heat exchange core part, 22
Flat tube, 22b lower tank part, 23 corrugated fin.

Claims (2)

[Claims] 1. A case (7) for forming a passage for conditioned air.
And an evaporator (2) housed in the case (7) and cooling the conditioned air. The evaporator (2) has a tube (2) through which a refrigerant flows.
2) and a heat exchange core part (21) composed of a fin member (23) joined to the tube (22). The tube (22) is provided at least below the heat exchange core part (21). An air conditioner including a tank section (22b) for distributing the refrigerant to the tube and collecting the refrigerant from the tube (22), wherein the tank section (22b) of the evaporator (2) in the case (7). ), A first covering wall (7a) for covering the tank portion (22b) is arranged at a portion on the upstream side of the air flow, and the first covering wall (7a) is provided on the first covering wall (7a). An opening (7) for discharging moisture from the upstream side to the downstream side of the air flow
b), and a second covering wall (7c) having a size larger than the opening area of the opening (7b) at a predetermined interval upstream of the first covering wall (7a) in the air flow. An air conditioner characterized by disposing. 2. The first cladding wall (7a) and the second cladding wall (7a).
The air conditioner according to claim 1, wherein the covering wall (7c) is formed integrally with the case (7) with resin.