JPH0458010A - Heat exchanger for automobile - Google Patents

Abstract

PURPOSE:To greatly increase the area of contact with a fluid to be cooled to improve heat exchange efficiency by installing plural recessed and projected parts on plate raw material of inner fins to increase the surface area, and bringing a part of the recessed and projected parts into contact with the inner surface of an outer cylinder and the outer surface of an inner cylinder. CONSTITUTION:Inner fins 10 are housed and installed in fluid passages 6, and each of the fins 10 consists of a brazing plate forming a soldered layer on the surface of a metallic plate raw material, and many recessed and projected parts 11 are provided to increase the surface area. The projected parts 11a of each inner fin 10 are brought into contact with the inner surface of an inner cylinder 4 or the outer surface of an inner cylinder 5 to be soldered, and the projected parts 11a of each inner fin 10 are brought into contact with the other inner fin 10 to be soldered. The area of contact with a fluid to be cooled can thus be increased to improve heat exchange efficiency.

Description

[Detailed Description of the Invention] <Industrial Application Field> The present invention relates to an automobile heat exchanger, which is disposed in a lower tank of an engine cooling radiator and is used to cool torque converter hydraulic oil of an automatic vehicle. It can be used as an oil cooler, etc.

<Prior art> As this type of heat exchanger, for example, Japanese Patent Application Laid-open No. 52-16999
No. 5, an inner cylinder is disposed within a cylindrical outer cylinder to form a passage for a fluid to be cooled, and a plurality of rectangular protrusion rows are formed in the circumferential direction in the passage, and a plurality of rectangular protrusion rows are formed in the circumferential direction. An inner fin is provided in which a row of protrusions in the axial direction are formed such that the rectangular protrusions are shifted by half a pitch from each other.

<Problems to be Solved by the Invention> The conventional heat exchanger described above has a relatively high performance because the rectangular protrusion row increases the contact area with the fluid to be cooled, A replacement is desperately needed.

Therefore, it is possible to further increase the contact area by narrowing the pitch of the rectangular protrusion rows, but the conventional protrusion shape has reached its limit, such as increasing the flow resistance of the cooled fluid, so a new inner fin development is necessary.

<Means for Solving the Problems> The present invention has been proposed in view of the above, and is arranged in the lower tank of an automobile radiator, and has an inner cylinder arranged inside a cylindrical outer cylinder to cool the fluid. In an automobile heat exchanger in which the outer cylinder is provided with an inlet and an outlet for the fluid to be cooled, and inner fins are provided in the passage, the inner fin is formed into a plate-like material. The inner fin is configured by arranging a plurality of uneven parts to increase the surface area, and the inner fin is installed between the outer cylinder and the inner cylinder so that at least a part of the uneven parts comes into contact with the inner surface of the outer cylinder and the outer surface of the inner cylinder. It is characterized by having a shape.

<Function> The uneven portion provided on the inner fin increases the surface area of the inner fin, increases the contact area with the fluid to be cooled, and improves heat exchange efficiency.

<Embodiment> Hereinafter, the present invention will be explained with reference to the embodiments shown in the drawings.The heat exchanger 1 according to the present invention has a radiator 2 as shown in FIG.
It is arranged in the lower tank 3 of the tank 3, and when it is alone, it has a cylindrical shape as shown in FIG.

The heat exchanger 1 includes a cylindrical outer cylinder 4 and an inner cylinder 5 disposed inside the outer cylinder 4, and the ends of the inner cylinder 5 and the outer cylinder 4 are electrically connected by joining means such as brazing. A fluid passage 6 is formed between the outer cylinder 4 and the inner cylinder 5 by sealing. In addition, an introduction lower is provided at one end of the outer cylinder 4 for introducing hydraulic oil of the torque converter, and an outlet port 8 is provided at the other end for returning the cooled hydraulic oil to the torque converter. It is. On the other hand, the cooling water in the radiator 2 can flow through the inner cavity 9 of the inner cylinder 5.

Specifically, the outer cylinder 4 is formed by extruding aluminum or the like and has a boss having a through hole on the outer surface near both ends, and the inner cylinder 5 is also formed by extruding aluminum or the like. The diameter of both ends of the material is enlarged to fit into the outer cylinder 4. That is, the inner cylinder 5
is a tapered portion 5 that slopes outward at both ends of the straight pipe portion 5a.
U) has b. Therefore, when the inner cylinder 5 is inserted into the outer cylinder 4, the tapered portion 5b is fitted to the end of the outer cylinder 4, and both ends are sealed by brazing or the like if necessary, the sealed fluid is released outside the inner cylinder 5. A passage 6 can be formed. Furthermore, base members 7' and 8' are fixedly attached to the boss of the outer cylinder 4 so as to constitute an introduction lower and an outlet 8. Inner fins 10, which will be described later, are located outside the straight pipe portion 5a of the inner cylinder 5.

The inner fin 10 is housed in the fluid passage 6 described above, and the inner fin 10 is made of a brazing plate with a brazing material layer formed on the surface of a metal plate-like material, and has many uneven parts 11. is provided to increase the surface area.

In addition, in the embodiment shown in FIGS. 3 and 4, the uneven portion 11
is the front side and the back side of the material, if the front side has the convex part 11a, the back side has four parts 11b, and the convex part 11a and the concave part itb.
For example, one side may have all convex portions 11a and the other side may have all concave portions 11b, or, for example, a row of convex portions 11a may be arranged in the horizontal direction. The rows of recesses 11b may appear alternately.

Further, although FIG. 3 shows a truncated cone-shaped uneven portion 11, the uneven portion 11 may have another shape, such as a hemispherical shape.

In addition, a through hole 12 is provided between each uneven portion 11 to pass through the plate-like material, and this plate-like material is connected to the inner fin 1.
When the inner fin 10 is placed in the fluid passage 6 with the inner fin 10 set at 0, fluid can pass through the upper and lower surfaces of the inner fin 10 .

Then, for example, the inner fin 10 is wrapped around the straight pipe portion 5a of the inner cylinder 5 to a width that avoids the bosses near both ends of the outer cylinder 4, and this is inserted into the outer cylinder 4 to form an assembly. By heating them in a furnace, the outer cylinder 4, inner fins 10, and inner cylinder 5 can be brazed together. At this time, both cap members 7', 8
' can also be brazed to the outer cylinder 4. In addition, in FIG. 5, the inner fins 10 are provided in three layers concentrically. In this case, the first inner fin 1 located at the outermost side
The tip of the convex portion 11a of the first inner fin 10a contacts the inner surface of the outer cylinder 4, and the tip of the concave portion 11b of the first inner fin 10a contacts the convex portion 11a of the second inner fin 10b located second from the outside. Similarly, the second inner fin 1
The tips of the four portions 11b of the fourth inner fin 10c contact the tips of the convex portions 11a of the third inner fin 10c located innermost, and the tips of the recesses 11b of the third inner fin 10c contact the outer surface of the inner cylinder 5. The inner fins 10 are brazed with the spacing maintained.

Therefore, according to the embodiment shown in FIG. 5, the height of the convex portion 11a is the same as that between the first inner fin loa and the second inner fin 10b and between the second inner fin lOb and the third inner fin 10c. The height is set twice, and the height between the outer cylinder 4 and the first inner fin 10a and between the inner cylinder 5 and the third inner fin 10c is set to the height of the convex portion 11a.

However, if the protrusions 11a of each inner fin 10 are arranged so that the protrusions 11a contact the base plate of the plate-like material without contacting each other, the interval between the inner fins 10 can be reduced between the protrusions. The height can be set to 11a.

Further, the convex portion 11a of each inner fin 10 is brought into contact with the inner surface of the outer cylinder 4 or the outer surface of the inner tube 5 to perform brazing, and the convex portion 11a of each inner fin 10 is brought into contact with the other inner fin 1o to perform brazing. Therefore, heat conduction from the outer cylinder 4 and the inner cylinder 5 is good. Therefore, radiator 2
Improves heat exchange with the cooling water inside.

According to the heat exchanger 1 configured as described above, the fluid to be cooled can pass between each inner fin 10 without resistance, and the contact area with the fluid is reduced by the uneven portions 11 provided on each inner fin 10. has increased significantly. Therefore, heat exchange between the fluid to be cooled and the cooling water of the radiator 2 is efficiently performed via the inner fins 10, and it is possible to provide a heat exchanger l with high heat exchange efficiency.

The embodiment shown in FIG. 6 is a heat exchanger 1 in which inner fins 10 are formed in one layer. According to this embodiment as well, the surface area of the inner fins 10 can be sufficiently expanded, a sufficient flow interval can be ensured, and a heat exchanger 1 with high heat exchange efficiency can be provided.

In FIG. 7, inner fins 10 are arranged in a spiral shape within the fluid passage 6. As shown in FIG. That is, the inner fin 10 provided with a plurality of uneven portions 11 is wound around the inner cylinder 5. When the inner fin 10 is wrapped around the inner cylinder 5, the uneven parts 11 come into contact with each other as appropriate and the outer edge extends toward the outer cylinder 4 while maintaining a gap. Surface area can be increased.

Therefore, this embodiment can also provide a heat exchanger l with high heat exchange efficiency.

In addition, the inner fin 10 having the above-described structure can be produced in one step by pressing a plate-shaped material, and is much more efficient than the conventional process of producing rows of protrusions one pitch at a time. can be created. Therefore, according to the present invention, it is possible to reduce the number of work steps and time.

The heat exchanger 1 described above has a total length of about 300 mm, an outer diameter of the outer cylinder 4 of about 30 rxm, and an outer diameter of the inner cylinder 5 of about 1 rxm.
6tnm, and the entire inner fin 10 (height from the tip of the protrusion 11a on the negative side to the tip of the protrusion 11a on the other side) is about 1+am.

Although the present invention has been described above with reference to the illustrated embodiments, the present invention is not limited to the embodiments described above, and can be implemented as appropriate without changing the configurations described in the claims.

<Effects of the Invention> In summary, the present invention is arranged in a lower tank of an automobile radiator, and an inner cylinder is arranged within a cylindrical outer cylinder to form a passage for a fluid to be cooled. In an automobile heat exchanger that includes an inlet and an outlet for a fluid to be cooled and has an inner fin in the passage, the surface area of the inner fin is increased by arranging a plurality of concave and convex portions on a plate-like material. This inner fin is installed between the outer cylinder and the inner cylinder so that at least a part of the uneven portion is in contact with the inner surface of the outer cylinder and the outer surface of the inner cylinder, so that the contact area with the fluid to be cooled is reduced. It is possible to significantly increase the heat exchange efficiency and provide a heat exchanger with good heat exchange efficiency. Furthermore, since the inner fins are easy to manufacture, they can be provided at low cost. Therefore, the present invention has extremely high practical value as it provides an inexpensive and high-performance heat exchanger.

[Brief explanation of the drawing]

The drawings show an embodiment of the present invention, in which Fig. 1 is a schematic front view of a radiator, Fig. 2 is a partially cutaway perspective view of a heat exchanger, Fig. 3 is a perspective view of an inner fin, and Fig. 4 is a schematic front view of a radiator. IV-IV in Figure 3
5 is a longitudinal sectional view of the heat exchanger, FIG. 6 is a longitudinal sectional view of another embodiment, and FIG. 7 is a longitudinal sectional view of still another embodiment. DESCRIPTION OF SYMBOLS 1... Heat exchanger, 2... Radiator, 3... Lower tank, 4... Outer cylinder, 5... Inner cylinder, 6... Fluid passage, lO... Inner fin, 11 ...Uneven parts. Figure 4 Figure 1 Ugly Figure 5

Claims (1)

[Claims] Disposed in a lower tank of an automobile radiator, an inner cylinder is arranged within a cylindrical outer cylinder to form a passage for a fluid to be cooled, and the fluid to be cooled is introduced into the outer cylinder. A heat exchanger for an automobile comprising an inlet and an outlet, and an inner fin provided in the passage, wherein the inner fin is configured by arranging a plurality of concave and convex portions on a plate-shaped material to increase the surface area, A heat exchanger for an automobile, characterized in that the inner fin is installed between the outer cylinder and the inner cylinder so that at least a part of the uneven portion is in contact with the inner surface of the outer cylinder and the outer surface of the inner cylinder.