JPH10328773A - Flat heat exchange tube and method for producing the same - Google Patents

Abstract

(57) [Summary] [PROBLEMS] To prevent occurrence of brazing failure between a reinforcing wall and an upper wall forming portion. Improve pressure resistance. A plate-shaped upper component member (20) having an upper wall forming portion (21) and left and right side wall forming portions (22) integrally formed on the left and right side edges thereof, and a lower wall forming portion (11) integrally formed on the left and right side edges thereof. A plate shape having a plurality of reinforcing wall forming portions 13 integrally formed on the lower wall forming portion 11 so as to extend in the length direction between the left and right side wall forming portions 12 and the left and right side wall forming portions 12 and to have a predetermined interval therebetween. The lower component 10 is provided. All reinforcement wall formations
13 height, left and right side wall forming part 12 and reinforcing wall forming part 13
Are equal in height. A plurality of notches 16 and 14 are formed at the upper edges of the left and right side wall forming portions 12 and all the reinforcing wall forming portions 13 at intervals in the length direction. Upper component
20 is put on the lower component 10 and the left and right side wall forming portions 22 are overlapped with the left and right side wall forming portions 12 of the lower component 10 so as to be overlapped with each other and both components are brazed to each other.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

The present invention relates to a heat exchanger for an automobile such as a condenser for a car air conditioner, an evaporator for a car air conditioner, an oil cooler for a car, a heat exchanger for electric equipment such as a condenser for a room air conditioner, and an oil cooler. The present invention relates to a flat heat exchange tube used for a heat exchanger for industrial machines such as a heat exchanger.

In this specification, the upper and lower sides and the left and right sides in FIGS. 1, 2 and 5 to 7 are respectively referred to as upper and lower sides and left and right sides. However, in the description regarding FIG. 8, the upper and lower sides and the left and right sides of FIG.

[0003]

2. Description of the Related Art Recently, as a capacitor for a car air conditioner, for example, as shown in FIG. ) And both ends are both headers (51) (52)
Are arranged in the ventilation gap between the parallel flat refrigerant flow pipes (53) (heat exchange pipes) connected to the refrigerant flow pipe and the adjacent refrigerant flow pipes (53). Corrugated fins (54) attached, inlet pipe (55) connected to the upper end of the peripheral wall of left header (51), and outlet pipe (56) connected to the lower end of the peripheral wall of right header (52) And a left partition plate (57) provided inside a position above the middle of the left header (51), and a right header (52)
A right partition plate (58) provided at a position lower than the middle of the number of refrigerant flow pipes (53) between the inlet pipe (55) and the left partition plate (57), and a left partition plate. The number of refrigerant flow pipes (53) between (57) and the right partition plate (58) and the number of refrigerant flow pipes (53) between the right partition plate (58) and the outlet pipe (56) are sequentially reduced from the top. By the time the gas-phase refrigerant flowing from the inlet pipe (55) flows out of the outlet pipe (56) as a liquid phase, the inside of the condenser is meandering in units of the respective passage groups. A so-called multi-flow type capacitor (see Japanese Patent Publication No. 3-45300) which is made to flow can realize high performance, low pressure loss and ultra compactness in place of a conventional serpentine type capacitor. It has been widely used.

[0004] The flat refrigerant flow pipe used in the condenser is required to have a pressure resistance because a high-pressure gas refrigerant is introduced into the inside thereof. In order to meet this demand and increase the heat exchange efficiency, the refrigerant flow pipe is made of an aluminum hollow extruded shape having flat upper and lower walls and a reinforcing wall that extends over the upper and lower walls and extends in the length direction. Had been. By the way, in view of the improvement of the heat exchange efficiency and the downsizing of the condenser, it is desirable that the flat refrigerant flow pipe is thin and the height is as low as possible. However, in the case of extruded shapes, there is a limit in reducing the pipe height and reducing the wall thickness due to the restriction on the extrusion technique.

Therefore, in order to solve this problem, the present applicant firstly described the upper and lower walls, the left and right side walls extending over the left and right side edges of the upper and lower walls, the upper and lower walls, and extending in the longitudinal direction and extending each other. A plurality of reinforcing walls provided at intervals in the longitudinal direction, having a plurality of parallel fluid passages therein, and a plurality of communication holes for allowing the parallel fluid passages to pass through the reinforcing walls at intervals in the longitudinal direction. A flat heat exchange tube formed by rolling a plate material, and forming a lower wall forming portion, right and left side wall forming portions integrally formed in the lower wall forming portion in an upright manner, and left and right side wall forming portions A plate-shaped lower component having a plurality of reinforcing wall forming portions integrally formed in the lower wall forming portion so as to extend in the length direction and to be spaced apart from each other at a predetermined interval, and left and right sides of the lower component Upper wall formation over the wall formation part The left and right side wall forming portions of the lower component have a thickness greater than the thickness of the reinforcing wall forming portion, and a step portion is provided at the upper end of the left and right side wall forming portion. A thin portion protruding above the reinforcing wall forming portion is formed through the upper wall, and a plurality of communication hole forming notches are formed at an upper edge of the reinforcing wall forming portion at intervals in the length direction. The left and right side edges of the member are placed on the steps of the left and right side wall forming portions, and the thin portion is bent inward to engage with the upper component, and in this state both components are brazed to each other A flat heat exchange tube has been proposed (see JP-A-9-26278).

The above-described conventional flat heat exchange tube is manufactured as follows. That is, on the peripheral surface of one of the work rolls of the rolling mill, left and right side wall forming portion forming annular grooves and a plurality of reinforcing wall forming portion forming annular grooves are formed so that the depths of both annular grooves are equal. The width and depth of all the reinforcing wall forming portion forming annular grooves are made equal, and the width of the left and right side wall forming portion forming annular grooves is made larger than the width of the reinforcing wall forming portion forming annular groove. A narrow annular groove for forming a thin-walled portion is formed on the bottom surface of the annular groove for forming both side wall portions, and a plurality of notch forming convex portions are circumferentially spaced on the bottom surface of the annular groove for forming the reinforcing wall formation portion. Is provided, and a lower component member is made by passing a metal plate through this rolling mill. In addition, an upper component is separately manufactured. Thereafter, the left and right side edges of the upper component are placed on the steps of the left and right side wall forming portions, and the thin portions are bent inward to engage with the upper component,
In this state, it is manufactured by brazing both components to each other.

However, in the conventional method for manufacturing a flat heat exchange tube, the width of the annular groove for forming the left and right side walls is larger than the width of the annular groove for forming the reinforcing wall, and the thin wall is formed. The depth of the left and right side wall forming portion forming annular grooves including the narrow width annular groove is greater than the depth of the reinforcing wall forming portion forming annular groove. Is provided with a notch forming projection, so that the volume of the annular groove for forming the left and right side wall forming portions becomes larger than the volume of the annular groove for forming the reinforcing wall forming portion. The metal material flowing from the left and right ends of the annular groove for forming the reinforcing wall forming portions, that is, the annular grooves for forming the reinforcing wall forming portion located adjacent to the annular grooves for forming the left and right side wall forming portions, is formed. It becomes easier to flow into the annular groove. Therefore, in the molded lower component, there is a problem that the height of the reinforcing wall forming portions at both ends is lower than the other reinforcing wall forming portions.

Moreover, in the molded lower component,
Since the height of the reinforcing wall forming portions at both ends is lower than the other reinforcing wall forming portions, a large gap is generated between the upper end of the reinforcing wall forming portions at both ends and the upper wall forming portion of the upper component. In the manufactured flat heat exchange tube, brazing failure occurs between the reinforcing wall forming portions at both ends and the upper wall forming portion of the upper component, and the required pressure resistance cannot be obtained. There was a problem. In addition, the part where the brazing failure occurred becomes the starting point,
There was also a risk that both components would peel off.

An object of the present invention is to solve the above-mentioned problems and to provide a flat heat exchange tube having improved pressure resistance without causing brazing failure between the reinforcing wall and the upper wall forming portion, and a method of manufacturing the same. To provide.

[0010]

Means for Solving the Problems and Effects of the Invention A flat heat exchange tube according to the present invention extends over the upper and lower walls, the left and right side walls extending over the left and right side edges of the upper and lower walls, and the upper and lower walls between the left and right side walls. A plurality of reinforcement walls extending in the length direction and provided at predetermined intervals from each other, having a plurality of parallel fluid passages therein, and a plurality of communication holes through which the parallel fluid passages pass through the reinforcement walls. A flat heat exchange tube that is opened, an upper wall forming portion, and a plate-shaped upper component having left and right side wall forming portions that are integrally formed in a drooping manner on left and right side edges of the upper wall forming portion, The lower wall forming portion, the left and right side wall forming portions formed integrally with the left and right side edges of the lower wall forming portion in an upright manner, and the lower portion extending in the length direction and leaving a predetermined interval from each other. Integrally formed upright on wall formation And a height of all the reinforcing wall forming portions of the lower structural member, and heights of the left and right side wall forming portions and the reinforcing wall forming portion are made equal to each other. A plurality of notches are formed in the upper edge of the left and right side wall forming portions and all the reinforcing wall forming portions of the lower component at intervals in the length direction, and the upper component is covered by the lower component. The left and right side wall forming portions are brazed to each other in a state where the left and right side wall forming portions overlap the outer sides of the left and right side wall forming portions of the lower component.

According to the flat heat exchange tube of the present invention, the heights of all the reinforcing wall forming portions of the lower constituent member and the heights of the left and right side wall forming portions and the reinforcing wall forming portion are made equal. In a state where the upper component is covered by the lower component, the upper ends of the left and right side wall forming portions and all the reinforcing wall forming portions are in contact with the lower surfaces of the upper wall forming portion of the upper component. And since both components are brazed to each other in this state, occurrence of brazing failure between all the reinforcing wall forming portions of the lower component and the upper wall forming portion of the upper component is prevented. You.
Therefore, the pressure resistance of the flat heat exchange tube is improved. In addition, since the occurrence of a brazing defect between all the reinforcing wall forming portions of the lower component member and the upper wall forming portion of the upper component member is prevented, the upper and lower portions starting from the portion where the brazing defect has occurred are started. It is possible to prevent the component members from peeling off.

Further, according to the flat heat exchange tube of the present invention, the heights of the left and right side wall forming portions and the reinforcing wall forming portion are equal, and the heights of the right and left side wall forming portions and the reinforcing wall forming portion are respectively set on the upper edges. Since a plurality of notches are formed at intervals in the length direction, the heights of all the reinforcing wall forming portions can be made equal. That is, this flat heat exchange tube
In this case, the volume of all the annular grooves formed on the peripheral surface of one of the work rolls can be made equal. Therefore, the metal material flowing from the metal base plate flows uniformly into the left and right side wall forming portion forming annular grooves and the left and right both side reinforcing wall forming portion forming annular grooves,
The height of the reinforcing wall forming portions at the left and right ends of the formed lower component is equal to the height of the other reinforcing wall forming portions. as a result,
The effects described above are derived.

Further, according to the flat heat exchange tube of the present invention, the two components are mutually connected in a state where the left and right side wall forming portions of the upper component overlap the outer sides of the left and right side wall forming portions of the lower component. As a result, leakage of fluid from the notches in the left and right side wall forming portions is prevented.

A method for manufacturing a flat heat exchange tube according to the present invention is a method for manufacturing a flat heat exchange tube according to claim 1, wherein left and right side walls are formed on a peripheral surface of one work roll of a rolling mill. The annular groove for forming the portion and the plurality of annular grooves for forming the reinforcing wall are formed so that the width and the depth of the two annular grooves are equal, and the plurality of annular grooves are formed on the bottom surfaces of the two annular grooves at circumferential intervals. The lower component is made by passing a metal plate through this rolling mill, the upper component is made separately from this, and then the left and right side wall forming portions of the upper component are formed. The upper constituent member is put on the lower constituent member so as to overlap the outer sides of the left and right side wall forming portions of the lower constituent member, and the two constituent members are combined. In this state, the two constituent members are brazed to each other. It is.

According to the flat heat exchange tube manufacturing method of the present invention, the left and right side wall forming portion forming annular grooves and the plurality of reinforcing wall forming portion forming annular grooves are formed on the peripheral surface of one of the work rolls of the rolling mill. Are formed so that the width and depth of both annular grooves are equal, and a plurality of notch forming projections are provided on the bottom surfaces of both annular grooves at intervals in the circumferential direction. The volume of all the annular grooves formed on the peripheral surface is equal, and when the lower component is made by passing the metal plate through this rolling mill, the metal material flowing from the metal plate forms the left and right side walls. Flow into the annular groove for forming the part and the annular groove for forming the reinforcing wall at both the left and right ends, and as a result, the height of the reinforcing wall forming part at the left and right ends of the lower component formed as a result is the other reinforcing wall forming part. Equal to the height of Therefore, as described above, the occurrence of poor brazing between all the reinforcing wall forming portions of the lower component and the upper wall forming portion of the upper component is prevented, and the pressure resistance of the flat heat exchange tube is reduced. Is improved. In addition, since the occurrence of a brazing defect between all the reinforcing wall forming portions of the lower component member and the upper wall forming portion of the upper component member is prevented, the upper and lower portions starting from the portion where the brazing defect has occurred are started. It is possible to prevent the component members from peeling off.

[0016]

DESCRIPTION OF THE PREFERRED EMBODIMENTS Hereinafter, embodiments of the present invention will be described.
This will be described with reference to the drawings. In the following description, the term “aluminum” includes an aluminum alloy in addition to pure aluminum.

FIG. 1 shows the entire configuration of a flat heat exchange tube according to the present invention, and FIGS.
4 to 7 show the manufacturing method.

1 to 3, a flat heat exchange tube (A)
Consists of flat upper and lower walls (1) and (2), double left and right walls (3) and (4),
(3) A plurality of reinforcing walls (5) extending between the upper and lower walls (1) and (2), extending in the length direction, and provided at a predetermined distance from each other, between the upper and lower walls (3) and (4). Aluminum fluid constituting the lower wall (2), the left and right side walls (3) and (4), and the reinforcing wall (5).
And a plate-shaped aluminum upper component member (20) constituting the upper wall (1) and the left and right side walls (3) and (4).

Lower wall (2) Adjacent reinforcing wall (5) on inner surface
The space between them and the part between the left and right side walls (3) and (4) and the reinforcing walls (5) at the left and right ends are spaced apart in the length direction in order to increase the heat transfer area. Multiple protrusions (7)
Are integrally formed in an upwardly protruding shape.

The left and right side walls (3) and (4) are formed on the left and right side edges of the upper wall (1) with right and left side wall forming parts (22) integrally formed therefrom,
The left and right side wall forming portions (12) integrally formed in a rising shape on the left and right side edges of the lower wall (2) are overlapped with each other in a state where the hanging left and right side wall forming portions (22) overlap with each other. It is formed by joining. The lower end portions of the left and right side wall forming portions (22) of the upper component member (20) extend below the lower wall (2), and are formed on the left and right side edges of the lower surface of the lower component member (10), and extend in the left-right direction. Inclined surface (15) inclined upward toward the outside
It is engaged and brazed. In addition, the lower component (1
A plurality of trapezoidal notches (16) are formed in the upper edge of the left and right side wall forming portions (12) at predetermined intervals in the length direction.

The reinforcing wall (5) is formed by joining a reinforcing wall forming portion (13) integrally formed with the lower wall (2) to the inner surface of the upper wall (1). In the reinforcing wall (5), parallel fluid passages
(6) A plurality of communication holes (8) are formed to allow communication. The communication holes (8) are arranged in a zigzag pattern when viewed from above. If the communication hole (8) is drilled,
The fluid flowing through (6) flows through the communication hole (8) in the width direction of the flat heat exchange tube (A),
The fluid is mixed throughout (6), and there is no temperature difference in the fluid between the fluid passages (6). Therefore, the heat exchange efficiency is improved. All communication holes (8) in each reinforced wall (5)
Is 10 to 40%, particularly 10%.
It is preferably within a range of about 30%, and more preferably about 20%. In this case, the effect of improving the heat exchange efficiency by forming the communication hole (8) becomes remarkable.
The communication hole (8) has a trapezoidal notch (14) formed at predetermined intervals on the upper edge of the reinforcing wall forming portion (13), and the opening is closed by the upper wall (1). It was formed. In this case, communication holes drilled in the plurality of reinforcing walls (5)
Since (8) is staggered when viewed from above, there is a joint between the two components (10) and (20) in the width direction of the flat heat exchange tube (A). High bonding strength is ensured.

The flat heat exchange tube (A) is manufactured as follows.

First, a plate-like aluminum lower component (10) as shown in FIG. 7 is formed using the apparatus shown in FIGS. Further, a plate-shaped aluminum upper component member (20) as shown in FIG. 7 is formed by roll forming.

In FIG. 7, the lower constituent member (10) includes a flat lower wall forming portion (11), and right and left side wall forming portions integrally formed on the left and right side edges of the lower wall forming portion (11). (12) and a plurality of reinforcing wall forming portions extending in the length direction integrally formed in a rising shape with a predetermined interval between both left and right side wall forming portions (12) of the lower wall forming portion (11). 13), the left and right side wall forming part (1
2) and trapezoidal notches (16) (14) are formed at the upper edge of the reinforcing wall forming portion (13) at predetermined intervals in the longitudinal direction thereof so as to be staggered when viewed from a plane. ing. Also,
The heights of all the reinforcing wall forming portions (13) of the lower component member (10), and the heights of the left and right side wall forming portions (12) and the reinforcing wall forming portion (13) are equal to each other. Further, a projection (7) is integrally formed on the upper surface of the lower wall forming portion (11), and inclined surfaces (15) are formed on both left and right side edges of the lower surface of the lower wall forming portion (11). .

In FIG. 7, the upper component (20) is formed integrally with a flat upper wall forming portion (21) in a hanging manner on both side edges of the upper wall forming portion (21), and the lower component (10) is formed. ) And left and right side wall forming portions (22) overlapping the left and right side wall forming portions (12). The width of the upper wall forming portion (21) of the upper component (20) is slightly larger than the width of the lower component (10), and can be covered by the lower component (10). The hanging length of the left and right side wall forming portions (22) of the upper component member (20) is equal to the rising length of the left and right side wall forming portions (12) of the lower component member (10). ) Is slightly longer than the one with the added thickness. Upper component
(20) consists of an aluminum brazing sheet having a brazing material layer on the lower surface, that is, the lower surface of the upper wall forming portion (21), and the inner surfaces of both left and right side wall forming portions (22).

In FIG. 4, an apparatus for manufacturing the lower component (10) includes an uncoiler (31) around which an aluminum sheet (30) is wound, a preliminary rolling mill (32), a finishing rolling mill (33), and a plurality of mills. Feed roll (34). Then, the aluminum sheet (30) wound up by the uncoiler (31) is unwound from the uncoiler (31) and sent to the preliminary rolling mill (32), and after passing through the preliminary rolling mill (32), the finishing rolling mill (33) to be subjected to finish rolling, whereby the lower component (1
0) is molded.

The pre-rolling mill (32) is used for the aluminum sheet (3
This is for forming thick portions on both side edges of (0).

The finishing mill (33) has a center work roll (3
5) and a plurality of satellite work rolls (36) arranged around the center work roll (35) at equal intervals in the circumferential direction. The center work roll (35) is configured to be rotated by a driving unit (not shown). Each satellite work roll (36) is connected to the center work roll (35) by a gear device (not shown).
By rotating all satellite work rolls (36)
Rotates at the same peripheral speed as the central work roll (35). Incidentally, each satellite work roll (36) may be provided with a driving means so that the satellite work roll (36) can be rotated at a constant peripheral speed with the center work roll (35). The finishing mill (33) includes a trapezoidal guide shoe (37) between the adjacent satellite work rolls (36) and a spring (38) for urging the guide shoe (37) toward the center work roll (35). ). Both edges of the guide shoe (37) are at the center work roll (3
It enters between 5) and the satellite work roll (36), and comes into sliding contact with the satellite work roll (36). The guide shoe (37) controls the elongation of the aluminum sheet (30) in the longitudinal direction while the aluminum sheet (30) passes through the finishing mill (33), and also controls the distance between the adjacent satellite work rolls (36). Swelling from the surface is suppressed. The suppression of the elongation in the length direction of the aluminum sheet (30) is also performed by rotating all the satellite work rolls (36) at the same peripheral speed as the center work roll (35). As a result, each groove (39) (40), recess (42) described later formed in the center work roll (35)
And convex portions (43) and (44), and an inclined surface (45), which will be described later, formed on the satellite work roll (36).
(0) is completely transferred to the lower component (1) having a desired shape.
0) is obtained. Further, since the elongation in the length direction of the aluminum sheet (30) is suppressed, it is possible to use a thinner aluminum sheet (30) as a base plate than a plate material used as a base plate in a conventional method. And material costs are lower. In addition, the rolling reduction can be smaller than that of the conventional method.

As shown in FIGS. 5 and 6, on the peripheral surface of the center work roll (35) of the finishing mill (33), the annular groove (39) for forming the left and right side wall forming portions and the reinforcing groove forming portion are formed. Annular groove
(40) is formed over the entire circumference. At this time, the width and depth of all the reinforcing wall forming portion forming annular grooves (40) should be equal, and the left and right side wall forming portion forming annular grooves (3
The width and depth of 9) and the annular groove (40) for forming the reinforcing wall forming portion are made equal. Also, between the annular groove (39) for forming the left and right side wall forming portions on the peripheral surface of the center work roll (35) and the annular groove (40) for forming the reinforcing wall forming portion adjacent thereto, and the adjacent reinforcing wall forming portion. A plurality of protrusion forming recesses (42) are provided at intervals in the circumferential direction between the part forming annular grooves (40). Furthermore, an annular groove (39) for forming the left and right side wall forming portions
In addition, cutout forming convex portions (43) and (44) are provided on the bottom surface of the reinforcing wall forming portion forming annular groove (40), respectively.

As shown in FIG. 5, a finishing mill (3
An inclined surface (45) inclined radially outward toward the left / right direction is formed at both left and right end portions of the peripheral surface of the satellite work roll (36) of (3).

Therefore, when the aluminum sheet (30) is continuously passed between the central work roll (35) and all the satellite work rolls (36), the lower constituent member (FIG. 7) 10) is molded.

Next, after the upper and lower structural members (20) and (10) are subjected to a degreasing treatment, a brazing flux is applied thereto.

Next, the upper component (20) is replaced with the lower component (10).
After fitting onto the left and right side wall forming portions (2
Bend the lower end of 2) inward in the left-right direction and lower component (10)
The two components (10) and (20) are temporarily fixed by being brought into close contact with the inclined surface (15).

Then, the two members (20) and (10) temporarily fixed are heated to the brazing temperature. Then, the lower component (10)
The left and right side wall forming portions (12) of the outer surface and the left and right side wall forming portions (22) of the upper component (20), the upper surface of the left and right side wall forming portions (12) of the lower component (10) and the reinforcing wall forming portion The upper end of (13) and the lower surface of the upper wall forming portion (21) of the upper component (20) are brazed respectively. Thus, the flat heat exchange tube (A) is manufactured.

In the above embodiment, the upper component (20)
The lower end portions of the left and right side wall forming portions (22) are bent inward in the left-right direction and are brought into close contact with the inclined surface (15) of the lower component member (10) to be engaged therewith. The entire lower surface of the lower wall forming portion of the lower component is flattened, and the lower end surfaces of the left and right side wall forming portions of the upper structural member are flush with the lower surface of the lower wall forming portion of the lower structural member. May be. Also, if the notch formed on the upper edge of the left and right side wall forming portion of the lower component can be covered by the left and right side wall forming portion of the upper component, the lower ends of the left and right side wall forming portions of the upper component, The lower component may be located at an intermediate portion of the height of the left and right side wall forming portions.

[Brief description of the drawings]

FIG. 1 is a cross-sectional view showing an embodiment of a flat heat exchange tube of the present invention.

FIG. 2 is a partially enlarged view of FIG.

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

FIG. 4 is a view schematically showing an apparatus for producing a lower component of the flat heat exchange tube of FIG. 1;

FIG. 5 is an enlarged sectional view taken along line VV of FIG.

FIG. 6 is a partially enlarged perspective view showing a peripheral surface of a central work roll of the apparatus of FIG. 4 in a developed manner.

FIG. 7 is a partially enlarged perspective view showing a state where upper and lower components are combined in a process of manufacturing the flat heat exchange tube of FIG. 1;

FIG. 8 is a front view of a condenser for a car air conditioner having a flat refrigerant flow pipe.

[Explanation of symbols]

(1) Upper wall (2) Lower wall (3) Left side wall (4) Right side wall (5) Reinforcement wall (6) Fluid passage (8) Communication hole (10) Lower component (11) Lower wall forming part (12 ) Left and right side wall forming part (13) Reinforcement wall forming part (14) (16) Notch (20) Upper component (21) Upper wall forming part (22) Left and right side wall forming part (35) Central work roll (39 ) Left and right side wall forming part forming annular groove (40) Reinforcement wall forming part forming annular groove (43) (44) Notch forming convex part

Continued on the front page (72) Inventor Masashi Sakaguchi 6,224 Kaiyama-cho, Sakai-shi Showa Aluminum Co., Ltd.

Claims (2)

[Claims] 1. An upper and lower wall, a plurality of left and right side walls extending over the left and right side edges of the upper and lower walls, and a plurality of the left and right side walls extending over the upper and lower walls and extending in the length direction and provided at a predetermined interval from each other. A flat heat exchange tube comprising a reinforcing wall, having a parallel fluid passage therein, and a plurality of communication holes passing through the parallel fluid passages in the reinforcing wall. A plate-shaped upper component member having left and right side wall forming portions formed integrally with the left and right side edges of the upper wall forming portion in a hanging manner, and a lower wall forming portion, and a rising integral with the left and right side edges of the lower wall forming portion. The formed left and right side wall forming portions, and a plurality of reinforcing wall forming portions that are integrally formed in the lower wall forming portion so as to extend in the length direction between the left and right side wall forming portions and to be spaced apart from each other by a predetermined distance. Consisting of a plate-shaped lower component having The heights of all the reinforcing wall forming portions of the component member and the heights of the left and right side wall forming portions and the reinforcing wall forming portion are made equal, and the height of the left and right side wall forming portions of the lower component and all the reinforcing wall forming portions are A plurality of notches are formed on the edge at intervals in the length direction, and the upper component is covered by the lower component, and the left and right side wall forming portions overlap the outer sides of the left and right side wall forming portions of the lower component. A flat heat exchange tube in which both components are brazed to each other in a folded state. 2. The method for manufacturing a flat heat exchange tube according to claim 1, wherein the left and right side wall forming portion forming annular grooves and the plurality of reinforcing walls are formed on the peripheral surface of one of the work rolls of the rolling mill. The annular grooves for forming the parts are formed so that the width and the depth of both annular grooves are equal, and a plurality of notch forming projections are provided on the bottom surfaces of both annular grooves at intervals in the circumferential direction. The lower component is made by passing the metal plate through this rolling mill, and the upper component is made separately from the lower component. Thereafter, the left and right side wall forming portions of the upper component are formed by the left and right side wall forming portions of the lower component. A method for manufacturing a flat heat exchange tube, comprising: combining an upper component member with a lower component member so as to overlap with the outside, and brazing the two component members to each other in this state.