JPH10267461A - Evaporator for overhead cooler - Google Patents

Abstract

PROBLEM TO BE SOLVED: To achieve good improvement in heat exchange efficiency while ensuring that the vertical thinness of the structure remains good. SOLUTION: Laterally on the two sides of a pair of header gropes 4a, 4b erected each pipe in parallel with the other pipe groups of heating tube elements are provided in a pair 5a, 5b. Each group of heating tube elements 5a, 5b is comprised of a plurality of heating tube elements 8, 8, each shaped flat with a passageway turned back inside, and corrugated type fins 9, 9, the elements and fins being laid one over another in alternate layers. The two ends of the turned-back passageway are put in tight communication with the inside of the pair of header pipes 4a, 4b. Of this pair of header pipes 4a, 4b, the inside of one 4a is divided by a partition plate 18 into two, that is, an inlet chamber 19 and an outlet chamber 20.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION The evaporator for an overhead cooler according to the present invention is incorporated in an air conditioner for a vehicle, and is used for cooling and dehumidifying a rear portion of a vehicle compartment.

[0002]

2. Description of the Related Art Conventionally, in order to cool and dehumidify the rear part of a vehicle interior, a blower for blowing cool air is installed in a console box or the like. A so-called overhead cooler is used, which is mounted in a ceiling portion of the vehicle so as not to obstruct the occupant. Such an overhead cooler has an evaporator and a blowing section fixed to the ceiling. As an evaporator constituting such an overhead cooler, an overhead cooler evaporator 1 as shown in FIG. 6 has been conventionally used.

[0003] The overhead cooler evaporator 1
Includes one or more heat transfer tubes 2, 2, a plurality of plate-type fins 3, 3, a distribution unit (not shown) for distributing a refrigerant to each of the heat transfer tubes 2, 2, It comprises a not-shown merging portion for merging the refrigerant from 2, 2 and a not-shown feed port and a not-shown feed port provided at each of the distributing portion and the merging portion. Each of the heat transfer tubes 2 and 2 is formed in a meandering shape in which a curved portion and a straight portion are alternately arranged, and the opening portions at both ends of each of the heat transfer tubes 2 and 2 communicate with the distribution portion and the junction portion, respectively. ing. In addition, a straight section provided between the heat transfer tubes 2 and 2 has a heat transfer tube 2 and
The plurality of plate-shaped fins 3, 3 are provided so as to penetrate both surfaces thereof. With this configuration, the overhead cooler evaporator 1
Can have a structure that is long in the lateral direction (the left-right direction in FIG. 5). The constituent members of the overhead cooler evaporator thus constructed are made of an aluminum alloy or a copper alloy, and are integrally connected by brazing or caulking.

[0004] The overhead cooler evaporator 1 constructed as described above operates as follows when assembled in a vapor compression refrigerator. That is, a low-temperature liquid refrigerant condensed and liquefied by a condenser (not shown) is sent from the condenser through the liquid tank and the expansion valve toward the inlet. The refrigerant sent into one of the header tanks of the pair of header tanks through the inlet passes through the inside of each of the heat transfer tubes 2 connected to the one of the header tanks. Flows toward the other header tank. In this case, the refrigerant takes off the surrounding heat and evaporates while flowing through the flow paths of the heat transfer tubes 2 and 2. As a result, the temperatures of the heat transfer tubes 2 and 2 and the plate-shaped fins 3 and 3 decrease. If air for air conditioning is sent from a blower to the outside of each of the heat transfer tubes 2 and 2 and the plate-type fins 3 and 3, this air is cooled and further dehumidified. Therefore, if this air is blown out as cold air from the blowing section toward the rear part of the vehicle compartment, the rear part can be cooled and dehumidified.

The reason why the overhead cooler evaporator 1 configured and operated as described above is structured to be long in the lateral direction as described above is from the viewpoint of space efficiency. That is, since the space of the ceiling portion of the front seat in the vehicle interior where the overhead cooler evaporator 1 is arranged is limited to a certain extent, the space for installing the overhead cooler evaporator 1 is sufficiently large in the vertical direction. It is difficult to do. Therefore, in order to dispose the overhead cooler evaporator 1 in this space, the dimension of the overhead cooler evaporator 1 must be reduced in the vertical direction. Moreover, this overhead cooler evaporator 1
In order to secure the desired performance by shortening
The area of the heat exchange portion must be increased, and the structure is inevitably long in the lateral direction.

[0006]

However, in the case of the conventional overhead cooler evaporator 1 constructed and operated as described above, its heat exchange performance may not always be sufficiently ensured. This is because, in the case of the conventional structure of the overhead cooler evaporator 1, the area of the contact portion between the plate-type fins 3, 3 and the heat transfer tubes 2, 2 constituting the overhead cooler evaporator 1 is equal to the plate-type fin 3, This is because the area is considerably smaller than the area of No. 3. That is, the heat transfer tubes 2 and 2 and the plate-type fins 3 and 3 are only in contact with each other by the heat transfer tubes 2 penetrating through the plate-type fins 3 and 3. It is difficult to secure the area of the part. As described above, the conventional overhead cooler evaporator 1 may not always ensure sufficient heat exchange performance.
There is a possibility that the cooling performance required by the overhead cooler using the overhead cooler evaporator 1 cannot be sufficiently secured. The overhead cooler evaporator of the present invention has been made in view of the above-described circumstances, and has been designed to sufficiently improve the heat exchange performance while keeping the vertically thin structure.

[0007]

SUMMARY OF THE INVENTION An overhead cooler evaporator according to the present invention comprises a feed port for feeding a refrigerant, a feed port for sending a refrigerant that has completed heat exchange, and a space between the feed port and the feed port. Connected to
A pair of header pipes arranged in parallel with each other, each having a U-shaped folded flow path whose both ends are in close communication with the inside of the pair of header pipes, and arranged in parallel with each other It comprises a plurality of flat heat transfer tube elements and a corrugated fin sandwiched between adjacent heat transfer tube elements, and comprises a pair of heat transfer tube element groups provided on both sides of the pair of header pipes. . Further, a partition plate is provided inside at least one of the pair of header pipes to partition the inside of the header pipe densely. The overhead cooler evaporator transfers the refrigerant to the inside of each of the heat transfer tube elements constituting each of the heat transfer tube element groups, while turning the refrigerant between the pair of header pipes, or each other. Flowing back and forth between

[0008]

The overhead cooler evaporator of the present invention constructed as described above has one pair of header pipes on both sides.
Since the pair of heat transfer tube element groups is provided, the horizontal length of the heat exchange portion of the overhead cooler evaporator with respect to the flow of air is equal to the horizontal length of the pair of heat transfer tube element groups. Length. Accordingly, the presence of the pair of header pipes can improve the coupling strength at the ends of the heat transfer tube elements constituting each of the heat transfer tube element groups. The length of the cooler evaporator in the lateral direction with respect to the flow of air can be increased. Therefore, the overhead cooler evaporator can sufficiently secure the required area of the heat exchange portion even if the vertical dimension is reduced.

The overhead cooler evaporator according to the present invention is different from the above-mentioned conventional overhead cooler evaporator using plate-type fins in that a so-called laminated type in which heat transfer tube elements and corrugated fins are alternately arranged. Since the heat exchanger is used, the heat exchange performance can be sufficiently improved while keeping the structure short in the vertical direction.

[0010] Further, since a partition plate is provided inside at least one of the pair of header pipes to partition the inside of the header pipe densely, the refrigerant is supplied to the inside of the heat transfer tube element. It can flow while turning between the pair of header pipes or moving back and forth between the heat transfer tube element groups. Therefore, the evaporator for an overhead cooler of the present invention lengthens the flow path of the heat exchange portion,
Since the flow rate of the refrigerant flowing through this flow path can be increased, the heat exchange performance can be further improved.

[0011]

1 to 5 show an example of an embodiment of the present invention. The overhead cooler evaporator 1a according to the present invention includes a pair of header pipes 4a and 4b arranged in parallel with each other, and a pair of header pipes 4a and 4b.
4b, a pair of heat transfer tube element groups 5 provided on both the left and right sides
a, 5b and upper and lower ends (upper and lower ends of FIG. 1) of one of the pair of header pipes 4a and 4b (front side in FIG. 1, lower side in FIGS. 3 to 4). It is composed of an inlet pipe 6 constituting the inlet and an outlet pipe 7 constituting the outlet.

The heat transfer tube element groups 5a and 5b are arranged in parallel with each other at appropriate intervals in the vertical direction (vertical direction in FIG. 1), and each is long in the horizontal direction (horizontal direction in FIG. 1). It comprises a plurality of flat heat transfer tube elements 8, 8 and corrugated fins 9, 9 sandwiched between vertically adjacent heat transfer tube elements 8, 8. The inside of the pair of header pipes 4a, 4b and the inside of the heat transfer tube elements 8, 8 are in close communication with each other. Therefore, a U-shaped folded flow path 10 is formed inside each of the heat transfer tube elements 8, 8, and both ends of the folded flow path 10 are closely connected to the inside of the pair of header pipes 4 a, 4 b. Let me. That is, as shown in FIG. 5, each of the heat transfer tube elements 8, 8 is composed of two flat plate members 11, 1 long in one direction (vertical direction in FIG. 5).
1 are superimposed. And each of these plate materials 11, 1
1 has a pair of protruding portions 12, 12 formed at one end (upper end in FIG. 5) in the longitudinal direction (upper direction in FIG. 5) with an interval therebetween. The leading edge of each of the protrusions 12 is
It is concave in an arc shape. A U-shaped recess 13 is formed on one surface of each of the plate members 11, 11 in a state where both ends of the recess 13 are continuous with the leading edges of the protruding portions 12, 12. Further, a number of protrusions 14 are provided inside the recess 13.
14 are formed. These projections 14, 14 disturb the flow of the refrigerant flowing inside the return channel 10 formed by the concave portion 13, and this refrigerant and the plate 1
The heat exchange efficiency between the heat transfer tube elements 8 and 1 is improved by improving the heat exchange efficiency between the heat transfer tube elements 1 and 11 and brazing the tips to each other.
8 is improved.

Each of the plate members 11, 11 is a set of two sheets,
The heat transfer tube element 8 is obtained by superimposing the recesses 13 in the middle in a state where the recesses 13 are opposed to each other, and joining the peripheral edges of the plate members 11 to each other in an air-tight and liquid-tight manner. The inside of each of the heat transfer tube elements 8, 8 formed in this manner is provided with the recess 13.
Are formed to form a U-shaped folded flow path 10. The heat transfer tube elements 8, 8 have the same shape and the same dimensions, and the number of the heat transfer tube elements 8, 8 constituting the heat transfer tube element groups 5a, 5b is equal to each other.

Further, the pair of header pipes 4a, 4b, which allow the inside of each of the heat transfer tube elements 8, 8 to closely communicate with each other,
Are formed by closing the openings at both ends of the tubular header bodies 15 and 15 with lids 16 and 16, respectively. As shown in FIG. 2, the same number of slit-shaped connection holes 17, 17 are formed on both side surfaces of the header bodies 15, 15 on the opposite side in the diameter direction.
They are formed in phase with each other. These connection holes 17, 1
Reference numeral 7 denotes a shape and a size in which the projections 12, 12 of a pair of plate members 11, 11, which constitute the heat transfer tube elements 8, 8, respectively, are overlapped with almost no gap. The pair of header pipes 4a, 4b
Among them, a partition plate 18 is provided at an intermediate portion inside one of the header pipes 4a, and the inside of the one header pipe 4a is communicated with the inlet chamber 19 communicating with the inlet pipe 6 and the outlet pipe 7. And an exit chamber 20 which is divided into two.

The members configured as described above are combined as shown in FIG. 1 and integrally joined by brazing in a heating furnace to form an overhead cooler evaporator 1a. The constituent members are made of an aluminum alloy, and a brazing material is previously laminated on a portion of at least one of the members to be joined to be brazed.

The overhead cooler evaporator of the present invention constructed as described above is incorporated in a vapor compression refrigerator as in the above-described conventional overhead cooler evaporator. Heat is exchanged between the refrigerant evaporating in the above and the air flowing outside. The air cooled by the heat exchange cools and dehumidifies the rear part of the vehicle interior.

That is, the overhead cooler evaporator 1a feeds the low-temperature liquid refrigerant condensed and liquefied by the condenser into the inlet pipe 6 via the liquid tank and the expansion valve. The refrigerant sent into the inlet chamber 19 of the one header pipe 4a through the inlet pipe 6 is connected to the plurality of heat transfer tubes constituting the pair of heat transfer tube element groups 5a and 5b, which are communicated with the inlet chamber 19. As shown by the arrows in FIG. 3, the pair of header pipes 4a, The header pipe 4b is sent toward the other header pipe 4b (the inner side in FIG. 1, the upper side in FIGS. 3 and 4).

The refrigerant sent to the other header pipe 4b returns inside the other header pipe 4b.
That is, the refrigerant sent inside the other header pipe 4b flows down inside the other header pipe 4b. Each of the plurality of heat transfer tube elements 8 among the plurality of heat transfer tube elements 8 and 8 communicating with the lower half portion of the other header pipe 4b and constituting the pair of heat transfer tube element groups 5a and 5b.
a, 5b, return channel 1 of heat transfer tube elements 8, 8 in lower half
4, the air is sent toward the outlet chamber 20 of the one header pipe 4a as indicated by an arrow in FIG. And
The air is sent out to an unillustrated compressor through the outlet pipe 7 connected to the outlet chamber 20. In this case, the refrigerant takes off the surrounding heat and evaporates while flowing through the return flow path 10. As a result, the temperature of the pair of heat transfer tube element groups 5a and 5b decreases. If air for conditioning is sent from a blower (not shown) to the heat transfer tube element groups 5a and 5b, the air is cooled. It is further dehumidified. Therefore, if this air is blown out as a cool air from the blowout section (not shown) toward the rear of the vehicle compartment, the rear can be cooled and dehumidified.

The overhead cooler evaporator of the present invention configured and operated as described above has a pair of header pipes 4.
a, a pair of heat transfer tube element groups 5a, 5b are provided on both sides of the overhead cooler evaporator 1a.
The horizontal length of the heat exchange portion with respect to the flow of air is equal to the total length of the pair of heat transfer tube element groups 5a and 5b in the horizontal direction. Therefore, the pair of header pipes 4
a, 4b, the heat transfer tube element groups 5a, 5b
In addition to being able to improve the coupling strength of the end portions of the heat transfer tube elements 8 and 8 constituting the above, while ensuring sufficient strength, the length of the overhead cooler evaporator 1a in the horizontal direction with respect to the flow of air is maintained. Can be increased. Therefore, the overhead cooler evaporator 1a can sufficiently secure the required area of the heat exchange portion even if the length in the vertical direction is reduced.

The overhead cooler evaporator of the present invention differs from the above-mentioned conventional overhead cooler evaporator 1a using plate-type fins in that heat transfer tube elements 8, 8 and corrugated fins 9, 9 are alternately arranged. , The heat exchange performance can be sufficiently improved. That is, in the structure of the laminated heat exchanger, the contact portions between the heat transfer tube elements 8 and 8 and the corrugated fins 9 and 9 correspond to the bent portions of the corrugated fins 9 and 9 and the heat transfer tube elements 8 and 9, respectively. Since the contact is with the flat portion of FIG. 8, the contact becomes a large number of linear contacts, and the area of the contact portion can be relatively large. Therefore, the heat exchange performance can be improved while the overhead cooler evaporator 1a of the present invention has a vertically short structure.

Further, since the overhead cooler evaporator of the present invention is provided with a partition plate 18 inside at least one of the pair of header pipes 4a and 4b to partition the inside tightly, Heat exchange performance can be further improved. That is, in the case of this example, the above 1
A partition plate 18 is provided inside one header pipe 4a of the pair of header pipes 4a and 4b.
The air flows between the pair of header pipes 4a and 4b while being turned back by the other header pipe 4b of the pair of header pipes 4a and 4b. Therefore, it is possible to lengthen the flow path of the heat exchange portion and increase the flow rate of the refrigerant flowing through this flow path. As a result, the overhead cooler evaporator 1a of the present invention can further improve the heat exchange performance.

In the case of the overhead cooler evaporator of the present embodiment, each of the heat transfer tube elements 8 constituting the pair of heat transfer tube element groups 5a and 5b has a structure corresponding to claim 2.
8 have the same number, the same shape, and the same size, and are arranged at symmetrical positions with respect to the pair of header pipes 4a and 4b. Thus, the pair of header pipes 4a, 4b
, The above-mentioned pair of heat transfer tube element groups 5a, 5b are in a symmetrical relationship with each other.
The flow of the refrigerant in b can be made uniform. Therefore, in the case of the overhead cooler evaporator 1a of this embodiment, if the same amount of air is sent to the pair of heat transfer tube element groups 5a and 5b, a uniform temperature distribution can be obtained in the lateral direction in the vehicle interior. . Therefore, even in the case of an overhead cooler evaporator that is long in the lateral direction, it is possible to minimize the discomfort felt by the occupant due to the difference in the lateral temperature distribution.

In addition to the above-described embodiment of the present invention, a partition plate is further provided inside both of the pair of header pipes 4a, 4b to flow through the heat transfer tube elements 8, 8. By increasing the number of turns of the refrigerant between the pair of header pipes 4a and 4b, the flow path of the refrigerant can be further lengthened. With this configuration, the flow rate of the refrigerant flowing through the flow path can be further increased, and the heat exchange performance of the overhead cooler evaporator can be further improved.

Further, a partition plate for densely partitioning the inside of each of the header pipes 4a, 4b is provided with a partition plate.
The inside of 4b may be partitioned in the horizontal direction. Then, for example, by combining the inside of each of the header pipes 4a and 4b with a partition plate that vertically separates the above, the refrigerant sent to one of the header pipes 4a through the inlet 6 is supplied to each of the heat transfer tube element groups 5a and 5b. In the heat transfer tube elements 8, 8. Then, the heat transfer tube elements 8, 8 constituting each of the heat transfer tube element groups 5a, 5b
Of the refrigerant flowing inside the pair of header pipes 4a,
4b or between the heat transfer tube element groups 5
Flow while moving back and forth between a and 5b. Thereby, the flow rate of the refrigerant can be further increased as compared with the case of the above-described embodiment of the present invention. As a result, the heat exchange performance of the overhead cooler evaporator can be further improved. However, in this case, the effect of obtaining a uniform temperature distribution in the lateral direction of the overhead cooler evaporator as described above may not be obtained.

[0031]

The evaporator for an overhead cooler according to the present invention is constructed and operated as described above, so that the heat exchange performance can be sufficiently improved while keeping the structure thin in the vertical direction.

[Brief description of the drawings]

FIG. 1 is a perspective view showing an example of an embodiment of the present invention.

FIG. 2 is a sectional view taken along line AA of FIG.

FIG. 3 is a sectional view taken along line BB of FIG. 2;

FIG. 4 is a sectional view taken along the line CC in FIG.

FIG. 5 is a partially exploded perspective view showing a heat transfer tube element constituting a heat transfer tube element group.

FIG. 6 is a perspective view showing an example of a conventional evaporator.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1, 1a Overhead cooler evaporator 2 Heat transfer tube 3 Plate-type fin 4, 4a Header pipe 5a, 5b Heat transfer tube element group 6 Inlet tube 7 Outlet tube 8 Heat transfer tube element 9 Corrugated fin 10 Folding channel 11 Plate material 12 Projection Part 13 Concave part 14 Projection 15 Header body 16 Lid 17 Connection hole 18 Partition plate 19 Inlet chamber 20 Outlet chamber

Claims (2)

[Claims] 1. A feed port for feeding a refrigerant, a feed port for sending a refrigerant having completed heat exchange, and a pair of parallel connected to each other between the feed port and the feed port. A header pipe, each of which has a U-shaped folded flow path with both ends closely communicating with the inside of the pair of header pipes, and a plurality of flat heat transfer tube elements arranged in parallel with each other; Equipped with corrugated fins sandwiched between adjacent heat transfer tube elements,
A pair of heat transfer tube element groups provided on both sides of the pair of header pipes, and a partition plate for densely partitioning the inside of at least one of the pair of header pipes. The refrigerant flows inside the heat transfer tube elements constituting each of the heat transfer tube element groups while turning between the pair of header pipes or moving back and forth between the heat transfer tube element groups. Evaporator for overhead cooler. 2. A plurality of flat heat transfer tube elements constituting a pair of heat transfer tube element groups, each having the same number, the same shape and the same size, and arranged at symmetrical positions with respect to the pair of header pipes. The evaporator for an overhead cooler according to claim 1, wherein