CN1926398A - Flat tube making platelike body, flat tube, heat exchanger and process for fabricating heat exchanger - Google Patents

Abstract

A flat tube making platelike body 15 is in the form of a single metal plate in its entirety and comprises two flat wall forming portions 17, 18 having the same width, a connecting portion 16 for interconnecting these portions 17, 18, side wall forming portions 9, 10 projecting from the respective flat wall forming portions 17, 18 and each formed integrally with one side edge of the flat wall forming portion opposite to the connecting portion 16, and first and second reinforcing wall forming portions 11, 12 integrally formed on each of the flat wall forming portions 9, 10. The first reinforcing wall forming portions 11 are butted against the respective second reinforcing wall forming portions 12 in pairs when the metal plate is folded into a hairpin form at the connecting portion 16. The first reinforcing wall forming portions 11 are given a smaller thickness than the second reinforcing wall forming portions 12 on the other flat wall forming portion 18 butted against the respective portions 11. The platelike body 15 gives an enhanced brazing joint strength to the reinforcing wall forming portions in fabricating a flat tube, and improved pressure resistance to the flat tube to be fabricated.

Description

Plate-shaped body for producing flat tubes, flat tube, heat exchanger and method for producing the heat exchanger

Cross References to Related Applications

This application is an application filed under 35 U.S.C. § 111(a) and a provisional filed under 35 U.S.C. § 111(b) on April 7, 2004 under 35 U.S.C. § 119(e)(1) Filing Date Benefit of Application No. 60/559,950.

technical field

The invention relates to a plate-like body for the manufacture of flat tubes used as heat exchange tubes for heat exchangers such as refrigerant tubes in condensers or evaporators of automotive air-conditioning units, for Oil pipes for automobile oil coolers, water pipes for automobile radiators and heat transfer medium pipes for (heater) radiator cores, the invention also relates to flat pipes, heat exchangers comprising such flat pipes and Method for making heat exchangers.

The term "aluminum" as used herein and in the appended claims includes aluminum alloys in addition to pure aluminum.

Background technique

In recent years, the following condenser, in which, for example, a chlorofluorocarbon refrigerant is used, is widely used in an automobile air-conditioning unit instead of a conventional coil condenser, and as shown in FIG. 13 , the condenser includes: a pair of headers 50, 51 arranged in parallel and spaced apart from each other; parallel flat refrigerant tubes 52 made of aluminum, each joined at its opposite ends to the two headers 50, 51; Corrugated aluminum fins brazed to adjacent tubes 52 in the airflow gap between adjacent refrigerant tubes 52; inlet tube 54 connected to the upper end of the circumferential wall of the first header 50; connected to the second The outlet pipe 55 at the lower end of the circumferential wall of the two headers 51; the first partition 56 arranged in the first header 50 and positioned above the middle of the header; Second divider 57 below the middle. The number of refrigerant tubes 52 above the first partition 56, the number of refrigerant tubes 52 between the first partition 56 and the second partition 57, and the number of partitions 52 below the second partition 57 Numbers decrease from top to bottom to provide multiple sets of channels. The refrigerant flowing into the inlet pipe 54 in the gas phase flows through the unit of the channel group in the condenser in a zigzag shape, and then flows out from the outlet pipe 55 in the liquid phase. A condenser having such a configuration is called a multi-flow condenser, and can achieve high efficiency, low pressure loss, and ultra-compactness.

The refrigerant tube 52 of the above-mentioned condenser is required to have very good heat exchange efficiency, and since high-pressure gaseous refrigerant is introduced into the refrigerant tube, the refrigerant tube is also required to have pressure resistance. Furthermore, the tubes need to have small wall thickness and low height to keep the condenser compact.

For example, publication JP-A No. 2003-53460 discloses a known flat tube which has very good heat exchange efficiency when used as such refrigerant tube 52. The flat tube disclosed in this gazette includes a pair of flat walls facing each other, opposing side walls interconnecting opposite pairs of sides of the flat walls, and a plurality of reinforcing walls interconnecting the pair of flat walls, the The reinforcing walls extend longitudinally of the tube and are spaced apart from each other by a predetermined distance, and the flat tube has a plurality of parallel flow channels inside it. Each reinforcing wall is made by brazing to butt each other respective corresponding wall forming portions of two sets of wall forming portions which stand inwardly from a flat wall and are connected to the flat wall. Integrally formed, another set of wall forming portions stands inwardly from the other flat wall and is integrally formed with the flat wall.

This flat tube is made of a plate-shaped body in the overall form of a single metal plate, which has two flat wall forming parts of the same width for making the two flat walls, so that the flat wall forming part a connecting portion interconnected so as to form one side wall, a side wall forming portion integrally formed with each flat wall forming portion and protruding from one side thereof opposite to the connecting portion so as to form the other side wall, and A plurality of reinforcing wall forming portions protruding integrally therewith from each flat wall forming portion, the flat tube is made by bending a plate-shaped body into a hairpin shape at a connecting portion, and brazing the side wall forming portions to butt each other , and each reinforcing wall forming portion on one flat wall forming portion is brazed to the corresponding reinforcing wall forming portion on the other flat wall forming portion abutted thereto.

However, since the thickness of the corresponding pair of reinforcing wall forming portions on the flat wall forming portion is equal, it has been found that the plate-shaped body for manufacturing a flat tube disclosed in the above publication has the following problems. The brazing operation for manufacturing the flat tube causes the brazing material to shrink, and as a result, as shown in FIG. Contraction at 63. This would weaken the strength of the brazed joint between the reinforcing wall forming portions 60, 61 to lower the pressure resistance of the resulting flat tube. Although it seems possible to make the refrigerant tubes, for example, 16 mm in width, 1.1 mm in height and about 0.5 mm in thickness at the most in order to provide a compact condenser, the above-mentioned problems arise in this case.

The object of the present invention is to overcome the above-mentioned problems and provide a plate-shaped body for manufacturing a flat tube capable of increasing the strength of the brazed joint between each corresponding pair of reinforcing wall forming parts and enabling the The pressure resistance of the flat tube is increased.

Contents of the invention

In order to achieve the above objects, the present invention includes the following means.

1) A plate-shaped body for manufacturing flat tubes in the integral form of a single metal plate, the plate-shaped body comprising: two flat wall forming portions having the same width and interconnected by connecting portions; side wall forming portions protruding in the same direction each integrally formed with one side of the flat wall forming portion opposite to the connection portion at which the metal plate is folded into a hairpin shape , the side wall forming portions are butted against each other; and a reinforcing wall forming portion integrally formed on each flat wall forming portion and protruding in the same direction as the side wall forming portion on that portion, when at the connecting portion When the metal plate is folded into a hairpin shape, the reinforcing wall forming part of one flat wall forming part is butted in pairs with the reinforcing wall forming part of the other flat wall forming part, and the pair of reinforcing wall forming parts to be butted against each other One has a smaller thickness than the other reinforcing wall forming portion.

2) The plate-like body for manufacturing a flat tube according to paragraph 1), wherein a thin reinforcing wall forming portion and a thick reinforcing wall forming portion are integrally formed on each flat wall forming portion.

3) The plate-like body for manufacturing a flat tube according to paragraph 2), wherein each flat wall forming portion integrally has thin reinforcing wall forming portions and thick reinforcing wall forming portions alternately provided thereon.

4) The plate-like body for producing a flat tube according to paragraph 1), wherein the thickness of the thin reinforcing wall forming portion is at most 0.5 mm.

5) The plate-shaped body for producing a flat tube according to paragraph 4), wherein the thickness of the thin reinforcing wall forming portion is at most 0.35 mm.

6) The flat tube-making plate-like body according to paragraph 1), wherein a difference between the thickness of the thin reinforcing wall forming portion and the thickness of the thick reinforcing wall forming portion is at least 0.05 mm.

7) The plate-shaped body for producing a flat tube according to paragraph 6), wherein the difference between the thickness of the thin reinforcing wall forming portion and the thickness of the thick reinforcing wall forming portion is at most 0.3 mm.

8) The plate-like body for manufacturing a flat tube according to paragraph 1), wherein when the paired reinforcing wall forming parts are butted with each other by folding the metal plate into a hairpin shape at the connecting part, the thickness of the thin reinforcing wall forming parts The opposite sides are positioned within the opposite sides of the thick reinforcing wall forming portion.

9) The plate-shaped body for manufacturing a flat tube according to paragraph 1), wherein the end face of one of the pair of reinforcing wall forming portions to be butted against each other has a ridge extending in the longitudinal direction of the reinforcing wall forming portion in the middle of its width, And the other reinforcing wall forming portion is provided in its end face with a groove extending in the longitudinal direction of the reinforcing wall forming portion for receiving the ridge.

10) The plate-shaped body for producing a flat tube according to paragraph 9), wherein the ridge is formed in the end surface of the thin reinforcing wall forming portion, and the groove is formed in the end surface of the thick reinforcing wall forming portion.

11) The plate-shaped body for manufacturing a flat tube according to paragraph 1), wherein the end face of the thick reinforcing wall forming portion is provided at the center in the width direction thereof with a groove extending in the longitudinal direction of the thick reinforcing wall forming portion.

12) The plate-shaped body for manufacturing a flat tube according to paragraph 1), wherein the thick reinforcing wall forming portion is provided in its end face with a groove extending in the longitudinal direction of the thick reinforcing wall forming portion for receiving Thin reinforcing walls form the ends of the sections.

13) A flat tube manufactured using the flat tube-making plate-shaped body according to paragraph 1), the flat tube is manufactured by folding the plate-shaped body into a hairpin shape at the connecting portion so that the side wall forming portions are butted against each other , and the paired reinforcing wall forming parts are butted against each other; in this state, the side wall forming parts are brazed to each other, and the paired reinforcing wall forming parts are brazed to each other so that the two flat wall forming parts Form a pair of opposing flat walls such that the joining portion forms one side wall, the side wall forming portions brazed together form the other side wall, and the pair of reinforcing wall forming portions brazed together form the reinforcing wall .

14) The flat tube according to paragraph 13), wherein the opposite sides of the thin reinforcement wall forming portion are positioned within the opposite sides of the thick reinforcement wall forming portion; and between the opposite end surfaces of the pair of reinforcement wall forming portions, and between A weld is formed between opposite sides of the end surface of the thin reinforcing wall forming portion and opposite sides of the end surface of the thick reinforcing wall forming portion.

15) A flat tube manufactured using the flat tube-making plate-shaped body according to paragraph 12), the flat tube is manufactured by folding the plate-shaped body into a hairpin shape at the connecting portion so that the side wall forming portions are butted against each other , making the paired reinforcing wall forming parts butt each other, and fitting the end of the thin reinforcing wall forming part into the groove of the thick reinforcing wall forming part; brazing the side wall forming parts to each other in this state, The paired reinforcing wall forming parts are brazed to each other so that the two flat wall forming parts form a pair of opposing flat walls, the connecting parts form one side wall, and the side wall forming parts brazed to each other form the other One side wall, and the pair of reinforced wall forming parts brazed together form the reinforced wall.

16) The flat tube according to paragraph 15), wherein between the end surface of the thin reinforcing wall forming portion and the bottom wall of the groove of the thick reinforcing wall forming portion, and between the thin reinforcing wall forming portion outside the groove A weld is formed between opposite sides of the portion and opposite sides of the end face of the thick reinforcing wall forming the portion.

17) A heat exchanger comprising: a pair of headers arranged in parallel at a distance from each other; a plurality of heat exchange tubes each comprising a flat tube according to paragraph 13) or 15) and which Opposite ends are joined to each header; and a fin disposed in each airflow gap between each pair of adjacent heat exchange tubes and brazed to its adjacent pair of heat exchange tubes.

18) A method for manufacturing a heat exchanger, characterized in that, using the plate-shaped bodies for making flat tubes according to any one of paragraphs 1) to 12), by folding each plate-shaped body into a hairpin shape making a plurality of folded bodies by abutting the side wall forming portions with each other and abutting the paired reinforcement wall forming portions with each other; preparing a pair of receptacles each having spaced apart receptacles for the folded bodies header, and prepare the fins; the pair of headers are spaced apart from each other and the folded body and the fins are alternately arranged; the opposite ends of the folded body are inserted into the corresponding sockets of the header; The side wall forming parts of the body of the body are brazed to each other and the paired reinforcing wall forming parts are brazed to each other to manufacture a flat tube, and at the same time as the flat tube is manufactured, the flat tube is brazed to the header and Each fin is brazed to its adjacent flat tube.

19) A refrigeration cycle using a chlorofluorocarbon refrigerant comprising a compressor, a condenser, an evaporator and a pressure reducing device, the condenser comprising a heat exchanger according to paragraph 17).

20) A refrigeration cycle using a chlorofluorocarbon refrigerant comprising a compressor, a condenser, an evaporator comprising a heat exchanger according to paragraph 17) and a pressure reducing device.

21) A supercritical refrigeration cycle, which includes a compressor, a gas cooler, an evaporator, a decompression device, and an intermediate heat exchanger, and the intermediate heat exchanger is used to make the refrigerant flowing out from the gas cooler and the refrigerant from the evaporator The outgoing refrigerant undergoes heat exchange, and where a supercritical refrigerant is used, the gas cooler comprises a heat exchanger according to paragraph 17).

22) A supercritical refrigeration cycle, which includes a compressor, a gas cooler, an evaporator, a decompression device, and an intermediate heat exchanger, and the intermediate heat exchanger is used to make the refrigerant flowing out from the gas cooler and the refrigerant from the evaporator The outgoing refrigerant undergoes heat exchange, and where a supercritical refrigerant is used, the evaporator comprises a heat exchanger according to paragraph 17).

23) A vehicle in which the refrigeration cycle according to paragraph 19) is installed as a vehicle air-conditioning device.

24) A vehicle in which the refrigeration cycle according to paragraph 20) is installed as a vehicle air-conditioning device.

25) A vehicle in which the refrigeration cycle according to paragraph 21) is installed as a vehicle air conditioner.

26) A vehicle in which the refrigeration cycle according to paragraph 22) is installed as a vehicle air-conditioning device.

For the plate-shaped body for making a flat tube shown in paragraph 1), the thickness of one of the paired reinforcing wall forming portions to be butted against each other is smaller than the thickness of the other reinforcing wall forming portion, therefore, when the metal is placed at the connecting portion When the panels are folded into a hairpin shape so that the portions abut each other, at least one side of the thinner reinforcing wall forming portion is positioned within a side of the thicker reinforcing wall forming portion. Therefore, when two reinforcing wall forming portions are brazed to each other in manufacturing a flat tube, there will be a A weld is formed between the edge and the edge of the end face of the thick portion positioned other than the thin portion. This prevents shrinkage within the weld. Therefore, the brazing joint strength of the two reinforcing wall forming portions is greater than that of a flat tube made using the plate-shaped body disclosed in the aforementioned publication, so that the pressure resistance of the flat tube is improved.

For the plate-shaped body for making a flat tube described in paragraphs 2) and 3), the two flat wall forming portions, the side wall forming portion and the reinforcing wall forming portion may be integrally formed therewith by rolling on a metal plate. The material thus exhibits improved fluidity, resulting in improved dimensional accuracy of the side wall forming portion and the reinforcing wall forming portion.

When using the plate-shaped body for manufacturing flat tubes described in paragraphs 4) and 5), the flat tubes to be manufactured can be made compact and lightweight, so that when the heat exchanger is equipped with such flat tubes, the heat exchanger can be made The overall compact and light weight.

Using the plate-like body for making the flat tube described in paragraph 6) ensures an increase in the brazing joint strength of the two reinforcement wall forming portions described with reference to paragraph 1), and improves the pressure resistance of the flat tube.

Manufacturing the plate-shaped body of the flat tube according to paragraph 7) prevents an increase in the weight of the flat tube to be manufactured because it is not particularly necessary to greatly increase the thickness of the thick reinforcing wall forming portion.

In manufacturing a flat tube using the plate-shaped body described in paragraph 8), when brazing a butt-joint pair of reinforced wall forming portions, there will be a gap between the end faces of the reinforcing wall forming portions and at the sides and sides of the end faces of the thin portion. A weld is formed between the sides of the end faces of the thick portion, thereby preventing a constriction between the end faces of the two portions. This provides an advantage of improving the brazing joint strength of the two reinforcing wall forming portions and improving the pressure resistance of the flat tube.

When the plate-shaped body described in paragraph 9) is used, the brazing area between the two reinforcing wall forming parts can be increased, and the brazing joint of the two reinforcing wall forming parts described with reference to paragraph 1) can be obtained. The strength is improved and the pressure resistance of the flat tube is further improved.

The advantages described with reference to paragraph 10) can be further accentuated by the plate-shaped body according to paragraph 9).

When the plate-shaped body described in paragraph 11) is used, the brazing area between the two reinforcing wall forming parts can be increased, and the brazing joint of the two reinforcing wall forming parts described with reference to paragraph 1) can be obtained The strength is improved and the pressure resistance of the flat tube is further improved.

When the plate-shaped body described in paragraph 12) is used, the brazing area between the two reinforcing wall forming parts can be increased, and the brazing joint of the two reinforcing wall forming parts described with reference to paragraph 1) can be obtained The strength is improved and the pressure resistance of the flat tube is further improved.

The flat tube according to paragraphs 13) and 16) has an increased brazed joint strength between the two reinforcing wall forming parts, so the pressure resistance of the tube is improved.

In the case of a heat exchanger according to paragraph 17), the flat tubes have sufficient pressure resistance even if the weight or size is reduced. This results in a reduction in size and weight of the heat exchanger as a whole.

Description of drawings

1 is a cross-sectional view showing an embodiment of a flat tube;

Figure 2 is an enlarged partial view of Figure 1;

Fig. 3 is a schematic diagram showing some steps of a method for manufacturing the flat tube of Fig. 1 with a plate-like body;

Fig. 4 is a cross-sectional view showing enlargedly the main part of Fig. 3(c);

5 is a cross-sectional view showing another embodiment of a flat tube;

Fig. 6 is a front view showing a plate-like body used to manufacture the flat tube shown in Fig. 5;

7 is a cross-sectional view showing another embodiment of a flat tube;

Figure 8 is an enlarged partial view of Figure 7;

Fig. 9 is a front view showing a plate-like body used to manufacture the flat tube shown in Fig. 7;

FIG. 10 is a cross-sectional view enlargedly showing first and second reinforcing wall forming portions of the plate-like body shown in FIG. 9;

Fig. 11 (a) is a view corresponding to Fig. 4, and shows modified first and second reinforcing wall forming portions;

FIG. 11( b) is a partial sectional view showing a flat tube manufactured with a plate-like body having the first and second reinforcing wall forming portions of FIG. 11( a);

Fig. 12 (a) is a view corresponding to Fig. 4, and shows another modified first and second reinforcing wall forming portions;

FIG. 12( b) is a partial sectional view showing a flat tube manufactured with a plate-like body having the first and second reinforcing wall forming portions of FIG. 12( a);

13 is a perspective view showing a condenser for an automobile air conditioner;

Fig. 14 is a partial sectional view showing a flat tube manufactured from a conventional plate-like body.

Detailed ways

Embodiments of the present invention will be described below with reference to the drawings. In the following description, the upper part, the lower part, the left-hand side and the right-hand side of FIG. 1 will be referred to as "upper", "lower", "left" and "right", respectively. In the drawings, the same parts will be indicated by the same reference numerals.

Fig. 1 shows a flat tube, Fig. 2 is a partial view of the flat tube, Fig. 3 shows steps of a method of manufacturing the flat tube using a plate-shaped body, and Fig. 4 is a partial view of Fig. 3(c).

Referring to FIG. 1, a flat tube 1 is made of aluminum and includes upper and lower flat walls 2, 3 (a pair of flat walls) opposed to each other so that the upper and lower flat walls 2, 3 are interconnected at their left and right opposite sides. The left and right opposite side walls 4, 5, and a plurality of reinforcing walls 6 interconnecting the upper and lower flat walls 2, 3, the reinforcing walls extend along the longitudinal direction of the tube and are spaced apart from each other on the right and left side walls 4, 5, the tube has a plurality of parallel flow channels 7 formed inside it. Although not shown, each reinforcing wall 6 is provided with a communication hole for each pair of adjacent flow channels 7 to communicate with each other through the communication hole, and the communication holes in the entire tube are arranged alternately when viewed from above .

The left side wall 4 includes a side wall forming portion 9 protruding downward integrally therewith from the left side of the upper wall 2 , and a side wall forming portion 10 protruding upward integrally therewith from the left side of the lower wall 3 , and The left side wall is formed by abutting the parts 9, 10 against each other and brazing the parts in this state. The right side wall 5 is made in one piece with the upper and lower walls 2,3.

The reinforcing wall 6 includes a reinforcing wall forming portion 11 protruding downward integrally therewith from the upper wall 2, and a reinforcing wall forming portion 12 protruding upward integrally therewith from the lower wall 3, and the reinforcing wall 6 is formed by making the wall portion 11 The corresponding pair of wall parts 11, 12 are formed by butting against the corresponding wall part 12 and brazing the corresponding pair. The thickness of the reinforcing wall forming portion 11 on one flat wall, ie, the upper wall 2 , is greater than that of the reinforcing wall 12 on the other flat wall, ie, the lower wall 3 . The thin reinforcing wall forming portion 11 will hereinafter be referred to as a “first reinforcing wall forming portion”, and the thick reinforcing wall forming portion 12 will hereinafter be referred to as a “second reinforcing wall forming portion”.

As shown in FIG. 2, the opposite sides of the first reinforced wall forming portion 11 are positioned within the opposite sides of the second reinforced wall forming wall portion 12, and the opposite side portions of the upper end surface of the second reinforced wall forming portion 12 protrude outward more than The first wall part 11 . The centerlines of the two reinforcing wall forming portions 11, 12 with respect to their thickness directions are preferably aligned. Welds 13 are formed between opposing end faces of the first and second reinforcing wall forming portions 11 , 12 and between opposing sides of the lower end face of the first wall portion 11 and sides of the upper end face of the second wall portion 12 .

The flat tube 1 is produced from a plate-like body in the manner shown in FIG. 3 .

The plate-shaped body is formed by rolling from an aluminum brazing sheet material having layers of brazing material on its opposite sides. As shown in Figure 3 (a), the plate-like body 15 includes: a flat upper wall forming part 17 (flat wall forming part) and a lower wall forming part 18 (flat wall forming part) for making the upper and lower walls 2, 3 forming part); make the upper and lower wall forming parts 17, 18 interconnected and integral with the connecting part 16 for forming the right side wall 5; respectively on the upper wall forming part 17 and the lower wall forming part 18 integrally with it side wall forming portions 9, 10 formed and each protruding upward from one side thereof opposite to the connection portion 16 so as to form the left side wall 4; and integrally therewith from the upper wall forming portion 17 and the lower wall forming portion 18, respectively Reinforcing wall forming portions 11 , 12 protruding upward are provided at intervals in the left-right direction. The first reinforcing wall forming portion 11 on the upper wall forming portion 17 and the second reinforcing wall forming portion 12 on the lower wall forming portion 18 are symmetrical about the vertical center line in the width direction of the plate-like body 15 .

The connection portion 16 is thicker than the upper and lower wall forming portions 17 , 18 . The thickness of the side wall forming portions 9 , 10 is greater than that of the first and second reinforcing wall forming portions 11 , 12 . The protruding height of the side wall forming portions 9 , 10 is about half the width of the connection portion 16 .

The side wall forming portion 10 on the lower wall forming portion 18 is provided with a ridge 19 extending in the longitudinal direction of the portion 10 at the center of the width of the top end thereof. On the other hand, the side wall forming portion 9 on the upper wall forming portion 17 is provided at its top end with a groove 20 extending in the longitudinal direction of the portion 9 into which the ridge 19 will be pressed.

The thickness of the first reinforcement wall forming portion 11 is smaller than that of the second reinforcement wall forming portion 12 . The thickness of the first reinforcing wall forming portion 11 is preferably at most 0.5 mm, more preferably at most 0.35 mm. The difference between the thicknesses of the first reinforcement wall forming portion 11 and the second reinforcement wall forming portion 12 is preferably at least 0.05 mm and not more than 0.3 mm.

For the case where the side wall forming portions 9, 10 and the first and second reinforcing wall forming portions 11, 12 are formed on one surface of an aluminum brazing sheet material covered with brazing material on its opposite face, in the case where the corresponding side walls are formed A layer of brazing material 21, 22 (see FIG. 4) is formed on the top ends of the portions 9, 10 and corresponding first and second reinforcing wall forming portions 11, 12, and on top of the upper and lower wall forming portions 17, 18. A layer of brazing material (not shown) is formed on the surface and the lower surface. The brazing material layers 21, 22 on the top ends of the side wall forming portions 9, 10 and the first and second reinforcing wall forming portions 11, 12 are thicker than those on the other portions. Ridges 19 and grooves 20 are also formed on or in the side wall forming portions 9, 10 when the aluminum brazing sheet is rolled. The top and opposite sides of the ridge 19 and the bottom and opposite sides defining the groove 20 also have a layer of brazing material.

The limit that is positioned at the opposite side of connecting portion 16 for the plate-shaped body 15 that is made into flat tube is gradually bent (see Fig. 3 (b)), and finally bends into hairpin shape, so that side wall forms parts 9, 10 and Each corresponding pair of parts 11, 12 abuts against each other, pressing the ridges 19 into the grooves 20 and obtaining a folded body 23 (see Fig. 3(c)). At this time, the top end surface of each first reinforcement wall forming portion 11 is in contact with the top end surface of the corresponding second reinforcement wall forming portion 12, and since the opposite sides of the first reinforcement wall forming portion 11 are positioned on the second reinforcement wall forming portion 12, so the opposite side portion of the top end surface of the second reinforcing wall forming portion 12 protrudes outward beyond the first reinforcing wall forming portion 11. A portion of the top end surface of the second reinforcing wall forming portion 12 protruding outward beyond the first reinforcing wall forming portion 11 is indicated by 12a (see FIG. 4 ). In the folded body 23 , the connecting portion 16 forms the right side wall 6 , the upper wall forming portion 17 forms the upper wall 2 , and the lower wall forming portion 18 forms the lower wall 3 .

Thereafter, the folded body portion 23 is heated to a predetermined temperature to braze the side wall forming portions 9, 10 and each pair of corresponding first and second reinforcing wall forming portions 11, 12 to each other using the above brazing material layer, And thereby form the left side wall 4 and the reinforcement wall 6 . At this time, as described above, between the opposite inner end surfaces of the first and second reinforcing wall forming portions 11, 12 and between the opposite sides of the inner end surface of the first wall portion 11 and the inner end surface of the second wall portion 12 A weld 13 is formed between the sides. In this way, the flat tube 1 is produced.

When the flat tube 1 is used as, for example, the refrigerant tube 52 of a condenser as shown in FIG. 13, such a flat tube 1 can be produced simultaneously with the production of the condenser. More specifically, the condenser was fabricated as follows. First a plurality of folded bodies 23 are prepared. A pair of aluminum headers 50, 51 each having a socket for the folded body and a plurality of corrugated aluminum fins 53 were also prepared. The pair of headers 50 , 51 are then spaced apart, the folded bodies 23 and fins 53 are alternately positioned, and the opposite ends of the folded bodies 23 are inserted into corresponding receptacles of the headers 50 , 51 . The obtained assembly is then heated at a predetermined temperature to braze the two side wall forming portions 9, 10 of each folded body 23 and the corresponding pair of reinforcing wall forming portions 11, 12 to each other , to form a flattened tube 1. At the same time, the flat tubes 1 are brazed to the headers 50, 51, and each wave-shaped fin 53 is brazed to the flat tube 1 adjacent thereto. Brazing is carried out with a layer of brazing material on the plate-shaped body 15 from which the flat tube is produced. In this way, the condenser is made.

Figure 5 shows another embodiment.

In the flat tube 30 of this embodiment, both the upper wall 2 and the lower wall 3 have thin first reinforcing wall forming portions 11 and thick (second) reinforcing wall forming portions 12 arranged alternately. The first reinforced wall forming portion 11 of the upper wall 2 and the second reinforced wall forming portion 12 of the lower wall 3 are butted against each other. The second reinforcement wall forming portion 12 of the upper wall 2 and the first reinforcement wall forming portion 11 of the lower wall 3 are butted against each other. Apart from these features, the construction of the tube 30 is the same as the tube 1 shown in FIG. 1 . The opposite sides of the first part 11 are positioned within the opposite sides of the second part 12 , while the opposite sides of the end faces of the second part 12 protrude outwardly beyond the first part 11 . A weld seam 13 is formed between the opposite end faces of the two parts 11 , 12 and between opposite sides of the end face of the first part 11 and opposite sides of the end face of the second part 12 .

The flat tube 30 is manufactured using a plate-shaped body 31 shown in FIG. 6 . The plate-shaped body 31 for making a flat tube has an upper wall forming portion 17 integrally having first reinforcing wall forming portions 11 and second reinforcing wall forming portions 12 alternately arranged at intervals in the left-right direction. This plate-like body 31 has a lower wall forming portion 18 integrally having first reinforcing wall forming portions 11 and second reinforcing wall forming portions 12 alternately arranged at intervals in the left-right direction. The first portion 11 of the upper wall forming portion 17 and the second portion 12 of the lower wall forming portion 18, and the second portion 12 of the upper wall forming portion 17 and the first portion 11 of the lower wall forming portion 18 are positioned with respect to the center line in the width direction symmetry.

Except for these features, the plate-shaped body 31 is the same as the plate-shaped body 15 shown in FIG. 3( a ), and the flat tube 30 is manufactured by the same method as shown in FIG. 3 .

7 and 8 show another embodiment of a flat tube.

In the flat tube 35 of this embodiment, the thick second reinforcing wall forming portion 12 is provided in its end face with a groove 36 extending longitudinally thereof, and the thin first reinforcing wall forming portion 11 to be butted against the portion 12 The end fits into this groove. The end of the thin first part 11 is pressed into the groove 36 of the second part 12 by press fit, and the end face and the opposite side of the end of the first part 11 are brazed to the bottom wall and the bottom wall of the second part 12 defining the groove 36. on the opposite side. In addition, as shown in FIG. 8 , between the end face of the first part 11 and the bottom wall of the groove defining the second part 12 , and between the opposite sides of the first part 11 outside the groove 36 and the end face of the second part 12 A weld 13 is formed between the opposite sides of the Due to the end face and the opposite side of the end of the first part 11 brazed on the bottom wall and sides of the groove 36 of the second part 12, the area of the brazed joint between the two reinforcing wall forming parts 11, 12 is larger than that of Fig. 2, thus increasing the strength of the brazed joint.

Apart from these features, the flat tube 35 is identical to the flat tube 30 shown in FIG. 5 .

The flat tube 35 shown in FIGS. 7 and 8 is produced from the plate-shaped body 37 shown in FIGS. 9 and 10 . The plate-shaped body 37 has an upper wall forming portion 17 and a lower wall forming portion 18 each having a first reinforcing wall forming portion 11 that is tapered, that is, the thickness decreases towards the end. These portions 17, 18 have second reinforcing wall forming portions 12 each forming in the end face a groove 36 extending along its entire length. Opposite sides defining the groove are vertical. As shown in FIG. 10 , the brazing material layer 22 is formed on the opposite side portions of the groove 36 in the end surface of the second reinforcing wall forming portion 12 and on the bottom wall defining the groove 36 .

Except for these features, the plate-shaped body 37 is the same as the body portion 31 shown in FIG. 6 , and the flat tube 35 is made by the same method as shown in FIG. 3 .

For the flat tube 35 shown in FIGS. 7 and 8, as in the case of the flat tube 1 shown in FIG. The reinforcing wall forming portion 12 may be formed only on the lower wall 3, that is, on the other flat wall.

Fig. 11 shows a modification of the first and second reinforcing wall forming portions 11, 12 of the plate-like body for making a flat tube.

Referring to Fig. 11 (a), the lower end surface of the first reinforced wall forming part 11 shown is integrally provided with a ridge 40 extending longitudinally of the part 11 in the middle of its width, and the second reinforced wall forming part 12 is shown in A groove 41 extending longitudinally of the portion 12 is provided in the upper end face of the portion 12 for receiving the ridge 40 . The ridge 40 has an outer peripheral surface with a substantially semicircular cross-section and a lower portion covered with the brazing material layer 21 . The groove 41 has an inner peripheral surface with a substantially semicircular cross-section that does not cover the brazing material layer 22 . The portion of the layer of brazing material 21 covering the ridge 40 fits tightly within the groove 41 .

When utilizing the plate-shaped body having such first and second reinforcement wall forming portions 11, 12 to manufacture a flat tube by the same method as shown in FIG. 3, as shown in FIG. 11(b), the two reinforcement walls Welds 13 are formed between opposite end surfaces of the forming portions 11 , 12 , and between opposite sides of the lower end surface of the first reinforcing wall forming portion 11 and opposite sides of the upper end surface of the second reinforcing wall forming portion 12 . The provision of the ridges 40 and the grooves 41 makes it possible to form a larger brazing area between the two parts 11 , 12 than is the case shown in FIG. 2 and thus obtain a greater brazing joint strength.

Fig. 12 shows another modification of the first and second reinforcing wall forming portions 11, 12 of the plate-like body for making the flat tube.

Referring to FIG. 12( a ), the first reinforcing wall forming portion 11 has a lower end surface protruding downward in the form of a circular arc in cross section. The upper end surface of the shown second reinforcing wall forming portion 12 is provided in the middle of its width with a groove 45 extending in the longitudinal direction of the portion 12 . The upper end surface of the second portion 12 has portions on opposite sides of the groove 45 each protruding upward in a circular arc in cross section. The groove 45 has a width slightly larger than its side portion and has a flat bottom surface. The inner peripheral surface defining the groove 45 is entirely covered with the brazing material layer 22 .

When utilizing the plate-shaped body having such first and second reinforcement wall forming portions 11, 12 to manufacture a flat tube by the same method as shown in FIG. 3, as shown in FIG. 12 (b), the two reinforcement walls Welds 13 are formed between opposite end surfaces of the forming portions 11 , 12 , and between opposite sides of the lower end surface of the first reinforcing wall forming portion 11 and opposite sides of the upper end surface of the second reinforcing wall forming portion 12 . The lower end surface of the first reinforced wall forming part 11 protrudes downward in the form of a circular arc in cross section, the groove 45 is formed in the second reinforced wall forming part 12, and the upper end surface of the second reinforced wall forming part 12 is recessed. On the opposite side of the groove 45 there are portions, each protruding upwardly in a circular arc in cross-section, so that the solder joint area between the two portions 11, 12 is larger than that shown in FIG. , so that the brazing joint strength is greater.

The first and second reinforcing wall forming parts 11, 12 shown in Figures 11 and 12 can be used in two ways: as shown in Figure 3 (a), the first reinforcing wall forming part 11 is arranged on a flat wall forming part , and the second reinforcing wall forming portion 12 is provided on the other flat wall forming portion; or as shown in FIG. 6 , the first and second reinforcing wall forming portions are alternately provided on each flat wall forming portion.

A heat exchanger comprising flat tubes made of said plate-like body is used as a condenser or evaporator of a refrigeration cycle, such as an automobile, in a vehicle equipped with the cycle including a compressor, a condenser, an evaporator, and a pressure reducing device , and in which chlorofluorocarbon refrigerants are used.

In addition, flat tubes made of the plate-shaped body are used as heat exchange tubes for a gas cooler or an evaporator of an air-conditioning device, such as a car, equipped with a compressor, a gas cooler, an evaporator decompressor, and an intermediate heat exchanger for exchanging heat between the refrigerant flowing from the gas cooler and the refrigerant flowing from the evaporator, and in which CO ₂ refrigerant or similar supercritical Refrigerant.

Industrial Applicability

The plate-shaped body for producing flat tubes of the present invention is used for producing flat tubes that are used as heat exchange tubes of heat exchangers, such as refrigerant tubes in condensers or evaporators for automotive air-conditioning units, for Oil pipes for automobile oil coolers, water pipes for automobile radiators and heat transfer medium pipes for (heater) radiator cores.

Claims (26)

1. A plate-shaped body for the manufacture of flat tubes in the integral form of a single metal plate, the plate-shaped body comprising: two flat wall forming portions having the same width and interconnected by connecting portions; side wall forming portions protruding in the same direction, each of which is integrally formed with one side of the flat wall forming portion opposite to the connecting portion, when the metal plate is folded into a hairpin shape at the connecting portion, said side wall forming portions are butted against each other; and a reinforcing wall forming portion integrally formed on each flat wall forming portion and protruding in the same direction as the side wall forming portion on that portion, when at the connecting portion When the metal plate is folded into a hairpin shape, the reinforcing wall forming portion of one flat wall forming portion is butted in pairs with the reinforcing wall forming portion of the other flat wall forming portion, One of the paired reinforcing wall forming portions to be butted against each other has a thickness smaller than that of the other reinforcing wall forming portion. 2. The plate-shaped body for manufacturing a flat tube according to claim 1, wherein a thin reinforcing wall forming portion and a thick reinforcing wall forming portion are integrally formed on each flat wall forming portion. 3. The plate-shaped body for manufacturing a flat tube according to claim 2, wherein each flat wall forming portion integrally has thin reinforcing wall forming portions and thick reinforcing wall forming portions alternately provided thereon. 4. The plate-shaped body for manufacturing a flat tube according to claim 1, wherein the thickness of the thin reinforcing wall forming portion is at most 0.5 mm. 5. The plate-shaped body for manufacturing a flat tube according to claim 4, wherein the thickness of the thin reinforcing wall forming portion is at most 0.35 mm. 6. The plate-shaped body for manufacturing a flat tube according to claim 1, wherein the difference between the thickness of the thin reinforcing wall forming portion and the thickness of the thick reinforcing wall forming portion is at least 0.05 mm. 7. The plate-shaped body for manufacturing a flat tube according to claim 6, wherein the difference between the thickness of the thin reinforcing wall forming portion and the thickness of the thick reinforcing wall forming portion is at most 0.3 mm. 8. The plate-shaped body for manufacturing a flat tube according to claim 1, wherein when the paired reinforcing wall forming parts are butted with each other by folding the metal plate into a hairpin shape at the connecting part, the thin reinforcing wall Opposite sides of the forming portion are positioned within opposite sides of the thick reinforcing wall forming portion. 9. The plate-shaped body for manufacturing flat tubes according to claim 1, wherein an end surface of one of the paired reinforcing wall forming parts to be butted against each other has a longitudinally extending edge along the reinforcing wall forming part in the middle of its width. The ridge, and the other reinforcing wall forming portion is provided in its end face with a groove extending in the longitudinal direction of the reinforcing wall forming portion for receiving the ridge. 10. The plate-shaped body for manufacturing a flat tube according to claim 9, wherein the ridges are formed in the end surface of the thin reinforcing wall forming portion, and the grooves are formed in the end surface of the thick reinforcing wall forming portion. 11. The plate-shaped body for manufacturing a flat tube according to claim 1, wherein the end face of the thick reinforcing wall forming portion is provided with a groove extending longitudinally of the thick reinforcing wall forming portion at the center in the width direction thereof. 12. The plate-shaped body for manufacturing flat tubes according to claim 1, wherein the thick reinforcing wall forming part is provided with a groove extending longitudinally along the thick reinforcing wall forming part in its end surface, and the groove is used for Fit into the end of the thin reinforcement wall forming part. 13. A flat tube manufactured with the flat tube manufacturing plate-shaped body according to claim 1, which is manufactured by folding the plate-shaped body into a hairpin shape at the connecting portion so that the side wall forming portions are butted against each other , and the paired reinforcing wall forming parts are butted against each other; in this state, the side wall forming parts are brazed to each other, and the paired reinforcing wall forming parts are brazed to each other so that the two flat wall forming parts Form a pair of opposing flat walls such that the joining portion forms one side wall, the side wall forming portions brazed together form the other side wall, and the pair of reinforcing wall forming portions brazed together form the reinforcing wall . 14. The flat tube according to claim 13, wherein the opposite sides of the thin reinforcing wall forming portion are positioned within the opposite sides of the thick reinforcing wall forming portion; and between opposite end surfaces of the paired reinforcing wall forming portion , and welds are formed between opposite sides of the end face of the thin reinforcing wall forming portion and opposite sides of the end face of the thick reinforcing wall forming portion. 15. A flat tube manufactured with the flat tube manufacturing plate-shaped body according to claim 12, which is manufactured by folding the plate-shaped body into a hairpin shape at the connecting portion so that the side wall forming portions are butted against each other , making the paired reinforcing wall forming parts butt each other, and fitting the end of the thin reinforcing wall forming part into the groove of the thick reinforcing wall forming part; brazing the side wall forming parts to each other in this state, The paired reinforcing wall forming parts are brazed to each other so that the two flat wall forming parts form a pair of opposing flat walls, the connecting parts form one side wall, and the side wall forming parts brazed to each other form the other One side wall, and the pair of reinforced wall forming parts brazed together form the reinforced wall. 16. The flat tube according to claim 15, characterized in that, between the end face of the thin reinforcing wall forming part and the bottom wall of the groove of the thick reinforcing wall forming part, and between the recess of the thin reinforcing wall forming part A weld is formed between opposite sides of the portion outside the groove and opposite sides of the end face of the thick reinforcing wall forming portion. 17. A heat exchanger comprising: a pair of headers arranged in parallel at intervals from each other; a plurality of heat exchange tubes each comprising a flat tube according to claim 13 or 15 and opposite to each other end-bonded to each header; and a fin disposed in each airflow gap between each pair of adjacent heat exchange tubes and brazed to its adjacent pair of heat exchange tubes. 18. A method for manufacturing a heat exchanger, characterized in that, using the plate-shaped body for manufacturing a flat tube according to any one of claims 1 to 12, by folding each plate-shaped body into a hairpin shape making a plurality of folded bodies by abutting the side wall forming portions with each other and abutting the paired reinforcement wall forming portions with each other; preparing a pair of receptacles each having spaced apart receptacles for the folded bodies header, and prepare the fins; the pair of headers are spaced apart from each other and the folded body and the fins are alternately arranged; the opposite ends of the folded body are inserted into the corresponding sockets of the header; The side wall forming parts of the body of the body are brazed to each other and the paired reinforcing wall forming parts are brazed to each other to manufacture a flat tube, and at the same time as the flat tube is manufactured, the flat tube is brazed to the header and Each fin is brazed to its adjacent flat tube. 19. A refrigeration cycle using a chlorofluorocarbon refrigerant comprising a compressor, a condenser, an evaporator and a decompression device, the condenser comprising the heat exchanger according to claim 17. 20. A refrigeration cycle using a chlorofluorocarbon refrigerant comprising a compressor, a condenser, an evaporator and a decompression device, the evaporator comprising the heat exchanger according to claim 17. 21. A supercritical refrigeration cycle comprising a compressor, a gas cooler, an evaporator, a decompression device and an intermediate heat exchanger, the intermediate heat exchanger is used to make the refrigerant flowing from the gas cooler flow out from the evaporator The outgoing refrigerant undergoes heat exchange, and wherein a supercritical refrigerant is used, said gas cooler comprising a heat exchanger according to claim 17. 22. A supercritical refrigeration cycle comprising a compressor, a gas cooler, an evaporator, a decompression device and an intermediate heat exchanger, the intermediate heat exchanger is used to make the refrigerant flowing out from the gas cooler and the refrigerant from the evaporator The outgoing refrigerant undergoes heat exchange, and wherein a supercritical refrigerant is used, said evaporator comprising a heat exchanger according to claim 17. 23. A vehicle in which the refrigeration cycle according to claim 19 is installed as a vehicle air conditioner. 24. A vehicle in which the refrigeration cycle according to claim 20 is installed as a vehicle air conditioner. 25. A vehicle in which the refrigeration cycle according to claim 21 is installed as a vehicle air conditioner. 26. A vehicle in which the refrigeration cycle according to claim 22 is installed as a vehicle air conditioner.

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