JPH11148795A - Combined heat exchanger - Google Patents

Abstract

PROBLEM TO BE SOLVED: To prevent thermal conduction from being generated between two heat exchangers as much as possible in a corrugated fin type heat exchanger having a main heat exchanger for cooling the cooling water of an engine formed integrally with a condenser for a car cooler. SOLUTION: Slits 2 are formed in the top parts and bottom parts of respective waves in the intermediate position widthwise a corrugated fin 1. The radii of curvature of the top parts and the bottom parts of a first curved part 3 located in one side from the respective slits 2 in the intermediate position widthwise the corrugated fin 1 are smaller than those of a second curved part 4 in the other side. The amplitude L1 of the wave of the first curved part 3 is longer than the amplitude L2 of the wave of the second curved part 4. Then, a first flat tube 5 is fixed in contact to the first curved part 3 and a second flat tube 6 is fixed in contact to the second curved part 4.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a composite heat exchanger in which a heat exchanger for cooling engine cooling water and a heat exchanger for car cooler are mainly integrated in an engine room of an automobile. , Having a common corrugated fin.

[0002]

2. Description of the Related Art In a plate fin type heat exchanger having a plurality of tube rows, it has been proposed to distribute a different heat exchange medium to each tube. In addition, since there is a temperature difference between the tubes in each row, a slit is formed between the tubes in order to prevent heat transfer from one tube to the other tube via the fins as much as possible. .

[0003]

In a composite heat exchanger using plate fins, it is necessary to arrange a number of plate fins in parallel through small gaps and to insert tubes one by one into each tube insertion hole. However, there is a disadvantage that the production is troublesome. In view of the above, an object of the present invention is to provide a composite heat exchanger using corrugated fins, which has a high mass productivity capable of preventing heat conduction between adjacent tubes via the fins as much as possible. I do.

[0004]

According to the composite heat exchanger of the present invention, a thin metal strip is bent to form a corrugated fin 1 so as to propagate a wave only in the longitudinal direction, and the corrugated fin 1 is formed. At the intermediate position in the width direction, cuts 2 are formed in the top and valleys of each wave in the traveling direction of the wave, and the first curved portion 3 on one side in the width direction is formed with each cut 2 as a boundary. The radii of curvature of the top and the valley are formed smaller than those of the second curved portion 4 on the other side, and the amplitude L ₁ of the wave of the first curved portion 3 becomes the amplitude L ₁ of the wave of the second curved portion 4. _Two
The first flat tube 5, which is formed longer and has a shorter diameter than the shorter diameter of the second flat tube 6 by the difference between the amplitudes of the waves of the two curved portions 3, 4, is fixed to the first curved portion 3. Then, the second flat tube 6 is fixedly contacted with the second curved portion 4, and different heat exchange media flow through the first flat tube 5 and the second flat tube 6, respectively, and the width of the corrugated fin 1. The cooling air flow 9 flows in the direction.

[0005] With such a configuration, in the compact composite heat exchanger having the common corrugated fin 1, the first flat tube 5 and the second flat tube 6 are provided.
The heat transfer between them can be effectively prevented by the cuts 2. That is, the notch 2 is disposed between the first curved portion 3 to which the first flat tube 5 is directly contact-fixed and the second curved portion 4 to which the second flat tube 6 is directly contact-fixed. At the shortest distance of the contact portion, heat transfer between the two can be prevented most efficiently. Moreover, since the amplitude L ₁ of the wave of the first curved portion 3 is formed longer than the amplitude L ₂ of the wave of the second curved portion 4, a step is generated there. Block. Then, the flow of the air flow 9 changes at the step, and the air flow 9 is stirred to promote heat exchange.

Next, a second aspect of the present invention is a preferred embodiment of the first aspect of the present invention, wherein the amplitude difference L ₁ -L ₂ between the waves of the two curved portions 3 and 4 is 0.2 mm. It is a composite heat exchanger that is ０．５0.5 mm. Next, a third aspect of the present invention is a preferred embodiment of the first aspect of the present invention, wherein the inner fin 7 is provided only in the second flat tube 6.
Is a composite heat exchanger in which is inserted. The second flat tube 6 into which the inner fin 7 is inserted has a minor diameter in the cross section larger than that of the first flat tube 5. Therefore, even if the inner fin 7 exists inside the second flat tube 6. ,
The heat exchange can be promoted by the presence of the inner fins 7 without increasing the flow resistance so much per unit sectional area.

Next, a fourth aspect of the present invention is a preferred embodiment of the third aspect of the present invention,
The flat tube 6 is a composite heat exchanger formed by bending a strip material into a tubular shape and joining both edges thereof in a liquid-tight manner.
Next, a fifth aspect of the present invention is a preferred embodiment of the third aspect of the present invention, wherein one strip is folded and folded into a flat cylindrical shape, and a sealing portion is provided at an intermediate portion in the width direction. 8 is formed, the first flat tube 5 is disposed on one side in the width direction with the seal portion 8 as a boundary, and the second flat tube 6 is integrally formed on the other side. . By configuring the first flat tube 5 and the second flat tube 6 with one strip in this way, it is possible to provide a composite heat exchanger with a small number of components and easy assembly.

The present invention according to claim 6 is a preferred embodiment of the invention according to claim 1, wherein engine cooling water for an automobile is introduced into the first flat tube 5 and the second flat tube 6 is provided. This is a composite heat exchanger configured to allow a refrigerant for cooling the vehicle to flow therein. As described above, the engine cooling water for the vehicle is guided into the first flat tube 5 and the refrigerant for cooling the inside of the vehicle flows through the second flat tube 6. And an economical combined heat exchanger can be provided.

[0009]

Next, an embodiment of the present invention will be described with reference to the drawings. FIG. 1 is a schematic perspective view of a corrugated fin 1 used in the composite heat exchanger of the present invention. This corrugated fin 1 is formed by bending a thin metal strip so that a wave travels only in the longitudinal direction, and a large number of louvers 10 which are respectively inclined are formed on the rising and falling surfaces of the wave. At the center of the corrugated fin 1 in the width direction, cuts 2 are formed at the top and valley of each wave in the traveling direction of the wave. The radius of curvature of the top and the valley of the first curved portion 3 on one side in the width direction is formed smaller than those of the second curved portion 4 on the other side, with the respective cuts 2 as boundaries. The amplitude L ₁ of the wave of the bending portion 3
Are formed longer than the amplitude L ₂ of the wave of the second curved portion 4.

As shown in FIGS. 2 and 3, the corrugated fins 1 are interposed between the first flat tubes 5 and the second flat tubes 6 arranged in two rows. Then, the first curved portion 3 of the corrugated fin 1 comes into contact with the flat side surface of the first flat tube 5 having a smaller minor diameter in the transverse cross section, and the second curved tube 3 having a larger minor diameter has a second curved portion.
The curved portion 4 comes into contact. The contact portions of the corrugated fin 1 and the first flat tube 5 and the second flat tube 6 are fixed to each other by brazing or soldering.
The difference between the short diameter of the cross section of the first flat tube 5 and the short diameter of the cross section of the second flat tube 6 is equal to L ₁ -L ₂ . This difference is preferably about 0.2 mm to 0.5 mm. Then, in the second flat tube 6 having a large short diameter,
The inner fin 7 is inserted. In this example, the width of the first curved portion 3 is formed longer than that of the second curved portion 4. The first flat tube 5 has a longer cross section than the second flat tube 6.

Both ends of each first flat tube 5 are connected to a pair of first headers (not shown), and both ends of each second flat tube 6 are also connected to a pair of second headers (not shown). In this example, the engine cooling water flows in the first flat tube 5, and the car cooler refrigerant flows in the second flat tube 6. The air flow 9 is shown in FIG.
As shown in FIG. 3, the refrigerant flows from the second flat tube 6 side to the first flat tube 5 side, thereby cooling the refrigerant in the second flat tube 6 and the engine cooling water in the first flat tube 5. .

FIG. 4 shows another embodiment of the present invention. In this embodiment, the second flat tube 6 is formed by bending a strip into a cylindrical shape and joining both edges thereof in a liquid-tight manner. Things. Also,
FIG. 5 shows still another example, in which the second flat tube 6 and the first flat tube 5 are formed integrally. That is, one strip member of the width is folded back and bent into a flat cylindrical shape, and a seal portion 8 is formed at the center in the width direction,
The first flat tube 5 is disposed on one side in the width direction with the seal portion 8 as a boundary, and the second flat tube 6 is disposed on the other side. In this example, the composite heat exchanger is a combination of a condenser for a car air conditioner and a heat exchanger for cooling engine cooling water. However, an oil cooler may be provided instead of the condenser.

[0013]

The combined heat exchanger of the present invention has the following advantages.
Since the cut 2 is formed at the boundary between the first curved portion 3 where the flat tube 5 contacts and the second curved portion 4 where the second flat tube 6 contacts, heat transfer between the two tubes via the corrugated fin 1 Can be effectively prevented. That is, since the notch 2 is provided at the boundary between the first curved portion 3 and the second curved portion 4 where the respective tubes are contact-fixed, the cut 2 is located at the shortest distance between the two contact portions, and the heat between the two tubes is most efficiently obtained. It can prevent transmission. Further, since a step is formed between the first bending portion 3 and the second bending portion 4 to which they are fixed in contact, the presence of the step further effectively prevents heat transfer between both tubes. I can do it. That is, the first bending portion 3
Amplitude L ₁ of the wave, since it is formed longer than the amplitude L ₂ of the wave of the second bending section 4, a level difference in its boundary occur,
Since the heat transfer distance between both tubes becomes longer by that amount, heat transfer between both tubes can be effectively prevented.

The presence of a step between the first curved portion 3 to which the first flat tube 5 is fixedly contacted and the second curved portion 4 to which the second flat tube 6 is fixedly contacted allows air flow. In the step 9, the flow changes at the step, and the mixture can be agitated to promote heat exchange. Further, the short diameter of the second flat tube 6 can be made larger than that of the first flat tube 5, and the flow resistance per unit cross-sectional area inside the second flat tube 6 is reduced by that much, so that more heat is generated. Exchange media can be distributed. And the heat exchange performance of the second flat tube 6 can be improved. Next, in the composite heat exchanger in which the inner fin 7 is inserted only in the second flat tube 6, the minor diameter in the cross section of the second flat tube 6 is larger than that of the first flat tube 5. The heat exchange performance can be further improved without increasing the flow resistance in the second flat tube 6 so much.

[Brief description of the drawings]

FIG. 1 is a schematic perspective view of a corrugated fin 1 used in a composite heat exchanger of the present invention.

FIG. 2 is an explanatory view showing a state of contact between each corrugated fin 1 used in the composite heat exchanger and a first flat tube 5 and a second flat tube 6;

FIG. 3 is a cross-sectional view taken along the line III-III in FIG. 2, showing the same contact state.

FIG. 4 is a sectional view of a main part of another combined heat exchanger of the present invention.

FIG. 5 is a sectional view of an essential part of still another combined heat exchanger of the present invention.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 Corrugated fin 2 Notch 3 1st bending part 4 2nd bending part 5 1st flat tube 6 2nd flat tube 7 Inner fin 8 Seal part 9 Air flow 10 Louver

 ──────────────────────────────────────────────────続 き Continued on the front page (72) Inventor Toshimitsu Kuriwada 3-25-3 Yoyogi, Shibuya-ku, Tokyo Inside Toyo Radiator Co., Ltd.

Claims (6)

[Claims] A corrugated fin 1 is formed by bending a thin metal strip so that a wave travels only in the longitudinal direction, and a top portion and a valley portion of each wave are provided at an intermediate position in the width direction of the corrugated fin 1. Cuts 2 are formed in the direction in which the wave travels, and the radius of curvature of the top and valley of the first curved portion 3 on one side in the width direction is the second curve on the other side, with each cut 2 as a boundary. It is formed smaller than those of the part 4 and its first
The amplitude L ₁ of the wave of the bending portion 3 is equal to the amplitude L ₁ of the wave of the second bending portion 4.
The first flat tube 5 is formed to be longer than _{2 and} has a shorter minor diameter than the minor diameter of the second flat tube 6 by the difference between the amplitudes of the waves of the two curved portions 3 and 4.
Are fixed in contact with the first curved portion 3, the second flat tube 6 is fixed in contact with the second curved portion 4, and the first flat tube 5 and the second flat tube 6 have different heat exchange media, respectively. And the cooling airflow 9 flows in the width direction of the corrugated fin 1. 2. The method according to claim 1, wherein an amplitude difference L ₁ -L ₂ between the waves of the curved portions 3 and 4 is 0.2 mm.
Combined heat exchanger that is ~ 0.5 mm. 3. The composite heat exchanger according to claim 1, wherein the inner fin 7 is inserted only into the second flat tube 6. 4. The composite heat exchanger according to claim 3, wherein the second flat tube 6 is formed by bending a strip material into a cylindrical shape, and both edges thereof are joined in a liquid-tight manner. 5. The device according to claim 3, wherein one of the members is folded and bent into a flat cylindrical shape, and a seal portion 8 is formed at a middle portion in the width direction, and one side in the width direction with the seal portion 8 as a boundary. The first flat tube 5 is disposed on the other side, and the second flat tube 6 is integrally formed on the other side. 6. A combined heat exchanger according to claim 1, wherein the engine cooling water for an automobile is guided into the first flat tube, and the refrigerant for cooling the inside of the vehicle flows through the second flat tube. vessel.