JP2000018867A - Tube material for heat exchanger and heat exchanger - Google Patents

Abstract

PROBLEM TO BE SOLVED: To assure an excellent heat transfer performance by molding a plurality of hollow parts in a sectional shape having continued protrusions and recesses of curved surfaces of a flat tube material having the plurality of the parts aligned in a width direction, thereby increasing a contact circumferential length of a heat exchanging medium per one channel while maintaining good processability. SOLUTION: In a condenser used for a refrigerant system of an air conditioner for a vehicle, a pair of right and left headers communicate with one another via a plurality of refrigerant tubes 10 arranged horizontally therebetween. The tubes 10 are used for a flat heat exchanger having a plurality of spaces 11 to become refrigerant channels formed therein, and manufactured by extrusion molding aluminum. The six spaces 11 aligned in parallel between the spaces 11a and 11b of both ends are all molded in the same sectional shape, arranged at an equal pitch, and a side 13 for forming the section is molded by continuing many curved surfaces 13a to 13l. Thus, a contact circumferential length of the medium is increased by protrusions and recesses of the surfaces 13a to 13l, thereby assuring an excellent heat transferring operation.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a heat exchanger tube used for a heat exchanger such as a condenser or an evaporator of a vehicle air conditioner, and a heat exchanger using the heat exchanger tube. It is about.

[0002]

2. Description of the Related Art A heat exchanger such as a condenser or an evaporator of a vehicle air conditioner uses a refrigerant as a heat exchange medium. As a refrigerant passage in such a heat exchanger, a tube material formed by extruding a metal material having excellent thermal conductivity, such as aluminum, is generally used.

FIG. 6 shows a cross section of a conventional tube member 1 for a heat exchanger, in which a total of eight spaces 2 serving as refrigerant passages are arranged in a row in the width direction. Has become. The cross-sectional shape of the space 2 is a rectangle formed of a flat surface except for the end spaces 2a and 2b located at both ends. Also, as for the end space portions 2a and 2b, the remaining three surfaces are flat surfaces except for the curved surfaces corresponding to both end surfaces (thickness portions) of the tube material 1. The curved surfaces of the end space portions 2a and 2b have a simple semicircular shape with no irregularities.

[0004]

In recent years, there has been an increasing demand for improving the performance of a heat exchanger without changing its size, or for reducing the size of the heat exchanger to ensure the same performance. As one method for responding to such a demand, the space 2 of the tube material 1 serving as the above-described refrigerant passage is provided.
It is conceivable to change the cross-sectional shape of and increase the coolant wetting perimeter per channel. However, in the case of the conventional tube material 1 described above, although the processability during extrusion molding is excellent, the refrigerant wetting perimeter per one flow path (space portion) cannot be made large, so that the liquefied refrigerant generates heat. There is a problem that it does not easily adhere to the surface to be replaced.

From such a background, as shown in FIG.
It is conceivable to provide the projection 3 on the surface of the space 2. However, when the projections 3 mainly composed of straight lines as shown in the figure are provided, the workability at the time of extrusion molding is significantly deteriorated. More specifically, since the strength of the core portion for forming the projection 3 is significantly reduced, it is necessary to extremely reduce the extrusion speed, and therefore there is a problem that mass production cannot be performed.

Japanese Unexamined Patent Publication (Kokai) No. 3-251688 discloses a method for manufacturing a heat exchanger tube material having inner fins, which is extruded and then crushed in the thickness direction to flatten it to a predetermined height. Have been. In such a manufacturing method, there are two steps of an extrusion molding step and a crushing step.
There is a problem that a process is required, which is disadvantageous in terms of productivity and cost. Moreover, the shape of the crushed inner fin is different from that after extrusion molding, and the influence of such crushing differs greatly depending on the location.

Therefore, the present invention provides a tube material for a heat exchanger, which can maintain good workability and can increase the contact circumference of the heat exchange medium per one flow path (refrigerant wetting circumference). The task is to provide a heat exchanger using materials.

[0008]

In order to solve the above problems, the present invention employs the following means. Claim 1
The heat exchanger tube material according to the above is a flat tube material provided with a plurality of hollow portions arranged side by side in the width direction, characterized in that the hollow portion has a cross-sectional shape formed by continuous curved surface irregularities Is what you do.

According to such a heat exchanger tube material, the heat transfer performance is improved since the contact circumference of the heat exchange medium flowing through the hollow portion is increased by the unevenness of the curved surface.

[0010] The tube material for a heat exchanger according to claim 2 is characterized by being formed by extrusion.

According to such a heat exchanger tube material, it becomes possible to easily mass-produce a heat exchanger tube material having excellent heat transfer performance.

A heat exchanger according to a third aspect is a flat tube material in which a plurality of hollow portions are provided side by side in the width direction, and the hollow portions have a cross-sectional shape formed by continuous curved unevenness. The heat exchanger tube material is used for a heat exchange medium flow path.

According to such a heat exchanger, since the heat exchanger tube having excellent heat transfer performance is used, the heat exchange capacity per unit area of the heat exchanger can be improved.

[0014]

Embodiments of the present invention will be described below with reference to the drawings. FIG. 1 shows a condenser 4 used in a refrigerant system of a vehicle air conditioner as an example of a heat exchanger. The condenser 4 has a function of cooling and condensing the high-temperature and high-pressure gas refrigerant sent from the compressor with outside air.

Now, the structure of the above-described capacitor 4 will be described. In the condenser 4, a pair of headers 5, 6 provided on the left and right sides communicate with each other by refrigerant tubes 10 arranged in a plurality in the horizontal direction, and fins 7 are arranged between the refrigerant tubes 10. In addition, the code | symbol 8 in a figure is a refrigerant | coolant inlet, 9 is a refrigerant | coolant outlet.

As shown in FIG. 2, the refrigerant tube 10 used here is a flat heat exchanger tube in which a plurality of spaces 11 serving as refrigerant channels are formed, and is formed by extruding aluminum. It was manufactured. As shown in detail in FIG. 3, the illustrated refrigerant tube 10 is a flat plate having a thickness (T) of about 2 mm and a width (W) of about 16 mm, and has a total inside in the width direction. Eight space portions 11 are provided in a line. Further, both ends of the refrigerant tube 10 are formed in a semicircular shape, and accordingly, the space portions 11 located at both ends are formed.
The shapes of a and 11b are different from the other six spaces 11 located at the center.

The space 11a located at the right end has a width (w) of about 1.65 mm and a thickness (t) of about 1.2 mm, and a wall surface forming a cross section thereof. Numeral 12 indicates a continuous irregularity of the curved surface, and there is no linear portion at all. That is, a first concave curved surface 12a having a radius of curvature of 0.6 mm, a first convex curved surface 12b having a radius of curvature of 0.5 mm, a second concave curved surface 12c having a radius of curvature of 0.2 mm, and a radius of curvature of A second convex curved surface 12d of 1.3 mm, a third concave curved surface 12e having a radius of curvature of 0.2 millimeter, and a third convex curved surface 12f having a radius of curvature of 0.5 millimeter continue to form one closed cross section. Is formed. The space 11b located at the left end is the same as the space 11a described above.
Is symmetrical.

The six spaces 11 arranged between the spaces 11a and 11b at both ends have the same sectional shape and are arranged at equal pitches. The space portion 11 has a width (w) of about 1.6 mm and a thickness (t) of about 1.2 mm, and a wall surface 13 forming a cross section of the space portion 11 has continuous curved irregularities. In this case, there is no linear part at all. That is, the first concave curved surface 13a having a curvature radius of 0.2 mm
And the first convex curved surface 13b having a radius of curvature of 0.2 mm
And the second concave curved surface 13c having a curvature radius of 0.2 mm
And the second convex curved surface 13d having a curvature radius of 0.2 mm
And a third concave curved surface 13e having a radius of curvature of 0.2 mm.
And the third convex curved surface 13f having a radius of curvature of 1.3 mm.
And a fourth concave curved surface 13g having a radius of curvature of 0.2 mm.
And the fourth convex curved surface 13h having a radius of curvature of 0.2 mm.
And the fifth concave curved surface 13i having a curvature radius of 0.2 mm
And the fifth convex curved surface 13j having a radius of curvature of 0.2 mm
And a sixth concave surface 13k having a radius of curvature of 0.2 mm.
And a sixth convex curved surface 131 having a radius of curvature of 1.3 mm.
Are continuously formed to form one closed section.

The respective radii of curvature as described above are set in consideration of productivity and workability during extrusion molding, that is, so as to obtain a uniform molding shape at an appropriate extrusion speed. According to the prototypes and tests of the inventor, in the case of a flat tube having a size suitable for a heat exchanger, the radius of curvature is shown in FIG.
It is known that a curved surface having a range from the maximum value shown in FIG. 4A to the minimum value shown in FIG. 4B can be mass-produced while maintaining good workability.

FIG. 4A shows the case where the radius of curvature of the continuous curved surface forming the space portions 11 and 11a shown in FIG. 3B is maximized. In this case, the wall surface 12 forming the cross section of the space 11a at the end has a radius of curvature of 0.6.
A first concave curved surface 12a of millimeter and a radius of curvature of 0.5
A first convex curved surface 12b of millimeters and a radius of curvature of 0.3
The second concave curved surface 12c of millimeter and the radius of curvature are 0.6
A second convex curved surface 12d having a diameter of 25 mm, a third concave curved surface 12e having a radius of curvature of 0.3 mm, and a third convex curved surface 12f having a radius of curvature of 0.5 mm are continuous,
It forms one closed section. The wall surface 13 forming the space 11 has a first radius of curvature of 0.3 mm.
A concave curved surface 13a and a first radius of curvature of 0.5 mm
A second convex surface 13b having a radius of curvature of 0.3 mm;
A concave curved surface 13c, a second convex curved surface 13d having a radius of curvature of 0.625 mm, a third concave curved surface 13e having a radius of curvature of 0.3 mm, and a third convex curved surface 13f having a radius of curvature of 0.5 mm; A fourth concave curved surface 13g having a radius of curvature of 0.3 mm and a fourth convex curved surface 13h having a radius of curvature of 0.625 mm are continuous to form one closed cross section.

FIG. 4B shows a continuous curved surface forming the space portions 11 and 11a shown in FIG. 3B with a minimum radius of curvature. In this case, the wall surface 12 forming the cross section of the end space 11a has a first concave curved surface 12a having a radius of curvature of 0.6 mm, a first convex curved surface 12b having a radius of curvature of 0.05 mm, and a radius of curvature. Is a second concave curved surface 12c having a radius of curvature of 0.1 mm, a second convex curved surface 12d having a radius of curvature of 0.05 mm, a third concave surface 12e having a radius of curvature of 0.1 mm, and a radius of curvature of 0.05 mm. , A fourth concave surface 12g having a radius of curvature of 0.1 millimeter, and a fourth convex surface 12h having a radius of curvature of 2.425 millimeters
And a fifth concave curved surface 12i having a curvature radius of 0.1 mm
And the fifth convex curved surface 12 having a curvature radius of 0.05 mm
j and a sixth concave curved surface 12 having a radius of curvature of 0.1 mm
k and a sixth convex curved surface 1 having a curvature radius of 0.05 mm
2l, seventh concave curved surface 1 having a radius of curvature of 0.1 mm
2 m and a seventh convex curved surface 12 n having a curvature radius of 0.05 mm are continuous to form one closed cross section. Further, the wall surface 13 forming the space 11 has a radius of curvature of 0.1.
A first concave curved surface 13a of 1 millimeter and a radius of curvature of 0.1 mm.
A first convex curved surface 13b having a radius of curvature of 0.05 mm, a second convex curved surface 13d having a radius of curvature of 0.05 mm, and a third convex surface 13d having a radius of curvature of 0.1 mm. A concave curved surface 13e, a third convex curved surface 13f having a radius of curvature of 0.05 millimeter, a fourth concave curved surface 13g having a radius of curvature of 0.1 millimeter, and a fourth convex curved surface 13h having a radius of curvature of 0.05 millimeter; A fifth concave surface 13i having a radius of curvature of 0.1 millimeter, a fifth convex surface 13j having a radius of curvature of 0.05 millimeter, a sixth concave surface 13k having a radius of curvature of 0.1 millimeter, and a radius of curvature of 2. 425 mm sixth convex curved surface 13 l
13 m of the seventh concave curved surface having a curvature radius of 0.1 mm
And the seventh convex curved surface 13 having a curvature radius of 0.05 mm
n and an eighth concave curved surface 13 having a radius of curvature of 0.1 mm
o, the eighth convex curved surface 1 having a curvature radius of 0.05 mm
3p and a ninth concave curved surface 1 having a radius of curvature of 0.1 mm
3q, a ninth convex curved surface 13r having a radius of curvature of 0.05 millimeter, a tenth concave curved surface 13s having a radius of curvature of 0.1 millimeter, and a tenth concave surface 13s having a radius of curvature of 0.05 millimeter.
A convex curved surface 13t and a first radius of curvature of 0.1 mm;
A concave surface 13u, an eleventh convex surface 13v having a radius of curvature of 0.05 mm, a twelfth concave surface 13w having a radius of curvature of 0.1 mm, and a twelfth convex surface 13x having a radius of curvature of 2.425 mm. Continuously form one closed section.

Therefore, the above-mentioned unevenness of the curved surface can be combined by appropriately changing the radius of curvature within a predetermined range, and is not limited to the illustrated one. Further, the number of the space portions 11 is not limited to the above-described eight, and may be changed as needed, for example, six or ten. In addition, the entire outer surface of the refrigerant tube 10 formed by extrusion molding is subjected to zinc spraying for the purpose of corrosion prevention utilizing a potential difference from the fin 7.

The refrigerant tube 1 manufactured as described above
No. 0 is brazed by inserting the respective tips into the connection ports provided in the headers 5 and 6 of the capacitor 4. The refrigerant tube 10 connected to the headers 5 and 6 serves as a refrigerant channel for flowing and circulating the refrigerant sent from the compressor (not shown) to the refrigerant inlet 8. In addition, fin 7
Increases cooling area by increasing the contact area with outside air,
Generally, what is processed into a corrugated shape is employed and adhered to the refrigerant tube 10. Therefore, the heat of the refrigerant flowing inside the refrigerant tube 10 is transmitted from the wall surfaces 12 and 13 of the refrigerant tube 10 to the fins 7 and further transmitted to the outside air flowing around the fins 7. The fins 7 are appropriately provided with louvers, slits, and the like, and the cooling efficiency is improved in consideration of making the flow of the outside air passing through the fins 7 evenly contact each surface.

The circumferential length of the wall forming the space 11 is increased by forming the refrigerant tube 10 having the space 11 having a cross section having continuous curved irregularities as described above. Is liquefied and easily attached to the wall surfaces 12 and 13 serving as heat exchange surfaces. When the coolant wetting circumference increases in this way, the heat transfer coefficient of the coolant tube 10 itself improves, so that the heat radiation capability of the condenser 4 using the coolant tube 10 also significantly improves. FIG. 5 is a graph on a logarithmic scale showing the relationship between the front wind speed and the heat radiation capacity of the capacitor. In this graph, the solid line represents the case using the refrigerant tube 10 having the curved flow path shape (FIG. 3) of the present invention, and the dashed line represents the one using the refrigerant tube 1 having the conventional rectangular flow path shape (FIG. 6). Comparing at the same front wind speed, it can be seen that the condenser 4 using the refrigerant tube 10 having the curved flow path shape has a very good heat radiation capability. Therefore, the refrigerant tube 1 having the curved flow path shape
By using 0, a capacitor 4 having an excellent heat transfer function and a high heat dissipation ability can be produced at low cost. In the above description, the heat exchanger is a condenser for condensing a gas refrigerant in an air conditioner.However, the heat exchanger tube material of the present invention is also applicable to other heat exchangers constituting an air conditioner such as an evaporator. Needless to say, the present invention can also be applied to various heat exchanger tube materials such as a radiator and an oil cooler.

[0025]

According to the present invention described above, the following effects can be obtained. According to the tube material for a heat exchanger according to the first and second aspects, the contact circumference of the heat exchange medium is increased by the unevenness of the curved surface, so that an excellent heat transfer action can be obtained. And it can be easily formed only by the extrusion process. In particular, since it has excellent workability for extrusion, mass production becomes possible, and it is possible to provide a tube material having a high heat transfer coefficient at a low cost. Play.

According to the heat exchanger of the third aspect, since the heat exchanger tube material having a high heat transfer coefficient is used at low cost, the heat exchange capacity of the heat exchanger can be improved at low cost. Becomes Therefore, for example, when the heat exchanger is a condenser, the air conditioner including the condenser as a constituent element has an effect that its input power can be reduced.

[Brief description of the drawings]

FIG. 1 is a perspective view showing a structure of a capacitor according to an embodiment of the present invention.

FIG. 2 is a perspective view showing a part of the appearance of the refrigerant tube of FIG. 1 as an example of a tube material for a heat exchanger.

3A is a sectional view taken along line AA of FIG. 2, and FIG. 3B is an enlarged view of a main part of FIG.

FIGS. 4A and 4B are diagrams illustrating a range of a radius of curvature of a suitable curved surface forming a space, where FIG. 4A is a maximum value and FIG.

FIG. 5 is a graph showing a relationship between a frontal wind speed and a heat dissipation capability in a capacitor.

FIG. 6 is a sectional view showing a conventional heat exchanger tube material.

FIG. 7 is a sectional view of a main part showing a conventional heat exchanger tube member provided with a projection.

[Explanation of symbols]

 4 Condenser 10 Refrigerant tube (tube for heat exchanger) 11 Space part 12, 13 Wall surface

 ──────────────────────────────────────────────────続 き Continued on the front page (72) Hiroshi Gomokawa 3-1-1 Asahimachi, Nishibiwajima-cho, Nishi-Kasugai-gun, Aichi Prefecture Inside Air Conditioning Works of Mitsubishi Heavy Industries, Ltd. (72) Inventor 1 Iwazuka-cho Takamichi Inside Nagoya Research Laboratory, Mitsubishi Heavy Industries, Ltd.

Claims (3)

[Claims] 1. A heat exchanger tube comprising: a flat tube member provided with a plurality of hollow portions arranged side by side in a width direction, wherein the hollow portions have a cross-sectional shape formed by continuous curved surface irregularities. Wood. 2. The heat exchanger tube material according to claim 1, wherein the tube material is formed by extrusion molding. 3. A flat tube material having a plurality of hollow portions arranged side by side in the width direction, wherein the hollow portions have a cross-sectional shape formed by continuous curved surface irregularities. A heat exchanger used for a medium flow path.