JPH10185471A - Heat exchanger - Google Patents

Abstract

PROBLEM TO BE SOLVED: To dispense with many experiments to improve the performance of a heat exchange and for providing a header with a partition sheet. SOLUTION: There are provided an inlet header 1 and an outlet header 2 both of which are spaced apart in parallel, and a parallel refrigerant flow tube 3 with both ends thereof connected to the header 1 and the header 2 respectively. The fluid which has flown into the inlet header 1 is led to flow into the entire refrigerant flow tube 3 in the same direction and reach to the outlet header 2. The refrigerant flow tube 3 is provided with the upper and lower walls, both side walls extending into the both side edges of the upper and lower walls, and two or more reinforcing walls which extend into the upper and lower walls in between both side walls, stretch in the length direction, and are arranged at predetermined intervals. The refrigerant flow tube 3 consists of a flat tube having a parallel fluid passageway inside. The flat tube is formed by a metal sheet. The reinforcing wall is integrally formed by the metal sheet in the shape of an inward rise. Two or more vent holes which vent each of the parallel fluid passageway are formed on each reinforcing wall. The opening ratio, the ratio of all the vent holes on each reinforcing wall, is kept in the range of 10-40%.

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 heat exchanger used as a heat exchanger for industrial machines.

[0002]

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 (81) (8
The two parallel refrigerant flow pipes (83) are disposed in the ventilation gap between the parallel flat refrigerant flow pipes (83) (heat exchange pipes) connected to 2) and the adjacent refrigerant flow pipes (83). Corrugated fins (84), an inlet pipe (85) connected to the upper end of the peripheral wall of the left header (81), and an outlet pipe (85) connected to the lower end of the peripheral wall of the right header (82). 86), a left partition plate (87) provided inside a position above the middle of the left header (81), and a right header (82).
A right partition plate (88) provided at a position lower than the middle of the number of refrigerant flow pipes (83) between the inlet pipe (85) and the left partition plate (87), and a left partition plate. The number of refrigerant flow pipes (83) between (87) and the right partition (88), and the number of refrigerant flow pipes (83) between the right partition (88) and the outlet pipe (86) are sequentially reduced from the top. By the time the gas-phase refrigerant flowing from the inlet pipe (85) flows out of the outlet pipe (86) as a liquid phase, the inside of the condenser is meandered 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.

[0003] 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.

[0004] In order to solve this problem, the present applicant has previously made a pair of flat rectangular walls opposed to each other and a pair of rectangular rectangular walls as refrigerant flow pipes used in the condenser shown in FIG. A pair of side walls spanning both side edges of the wall, and a plurality of reinforcing walls extending between the two side walls and extending in the length direction and provided at a predetermined interval from each other and extending in the lengthwise direction. A flat tube having a fluid passage, wherein the flat tube is formed of a metal plate,
There has been proposed a structure in which a reinforcing wall is integrally formed in an inwardly protruding shape from a metal plate, and a plurality of communication holes are formed in each reinforcing wall to allow parallel fluid passages to pass between each other (Japanese Patent Laid-Open No. Hei 6-281).
373).

However, in the capacitor shown in FIG.
In the case of using either a refrigerant flow pipe made of an aluminum hollow extruded shape or a refrigerant flow pipe made of a flat tube formed from a metal plate described in JP-A-6-281373, the following is required. It turned out to be a problem. That is, in the condenser shown in FIG. 21, in order to make the refrigerant flow uniformly in each refrigerant flow pipe, and to improve the heat exchange performance by reducing the pressure loss, the space between the inlet pipe and the left partition plate is improved. The number of refrigerant flow pipes, the number of refrigerant flow pipes between the left partition and the right partition, and the number of refrigerant flow pipes between the right partition and the outlet pipe are optimized by conducting many experiments. And the task is cumbersome. Further, since it is necessary to attach the partition plate to the header, there is a problem that the operation is troublesome, and the number of parts increases and the cost increases.

An object of the present invention is to provide a heat exchanger which solves the above-mentioned problems, does not require many experiments for improving heat exchange performance, and does not need to provide a partition plate.

[0007]

SUMMARY OF THE INVENTION A heat exchanger according to the present invention comprises an inlet header and an outlet header which are arranged in parallel at a distance from each other, and a parallel-shaped heat exchanger in which both ends are respectively connected to both headers. With heat exchange tubes, the fluid flowing into the inlet header flows in the same direction in all the heat exchange tubes to reach the outlet header,
A heat exchange tube has a pair of flat rectangular walls facing each other, both side walls spanning both side edges of the rectangular walls, and both side walls extending between the two side walls and extending in a longitudinal direction and mutually extending between the two side walls. A flat tube having a plurality of reinforcing walls provided at predetermined intervals and having parallel fluid passages therein, wherein the flat tube is formed of a metal plate; A plurality of communication holes are formed integrally with each other in a protruding shape, and a plurality of communication holes through which parallel fluid passages are formed are formed in each reinforcing wall, and an opening ratio, which is a ratio occupied by all the communication holes in each reinforcing wall, is 10 to 40. %.

In the above description, the reason why the opening ratio, which is the proportion of all the communication holes in each reinforcing wall, is limited to the range of 10 to 40% is that if it is less than 10%, the thermal conductance is low, and it exceeds 40%. Even so, the thermal conductance no longer increases, only the coefficient of friction increases, and the heat exchange performance cannot be improved. The opening ratio is preferably in the range of 10 to 30%,
In particular, it is desirable to be within the range of 15 to 20%.

[0009] The cross-sectional area of the communication hole is set to a size such that sufficient exchange of the refrigerant is performed, there is no possibility that the refrigerant is blocked by the brazing that has flowed during brazing, and the pressure resistance of the refrigerant flow pipe is not reduced. deep. Further, the pitch of the communication holes is set so as not to lower the pressure resistance of the refrigerant flow pipe, and to allow sufficient exchange of the refrigerant.

It is preferable that the communication holes formed in the plurality of reinforcing walls are staggered when viewed from a direction orthogonal to the rectangular wall. However, it is not limited to this.

The pitch of the reinforcing walls in the pipe width direction is preferably 4 mm or less. When the pitch of the reinforcing wall exceeds 4 mm, the heat exchange efficiency is deteriorated.

It is preferable that the height of the reinforcing wall be 2 mm or less. If the height of the reinforcing wall exceeds 2 mm, not only is it difficult to reduce the size of the heat exchanger, but also the resistance of the passing air increases and the heat exchange efficiency deteriorates.

According to the above-described heat exchanger of the present invention, there are provided an inlet header and an outlet header which are arranged in parallel at an interval from each other, and a parallel heat exchanger tube whose both ends are respectively connected to both headers. In addition, since the fluid flowing into the inlet header flows in all the heat exchange tubes in the same direction to reach the outlet header, it is not necessary to provide a partition plate at the inlet header and the outlet header. It is not necessary to perform many experiments for improving the heat exchange performance as in the case of the conventional multi-flow type heat exchanger shown in FIG. In addition, since it is not necessary to attach the partition plate to the header, the operation is not required, and the number of parts is reduced, so that the cost is reduced. Further, since there is no need to provide a partition plate at the inlet header and the outlet header, the pipe passage resistance is smaller than that of the conventional multi-flow type heat exchanger shown in FIG. 21, and the load on the compressor is reduced.

[0014] The heat exchange tube is provided with a pair of flat rectangular walls opposed to each other, both side walls spanning both side edges of the both rectangular walls, and a longitudinal direction extending between the both side walls. A flat tube having a plurality of reinforcing walls extending parallel to each other and provided at a predetermined interval from each other, and having a parallel fluid passage therein, wherein the flat tube is formed of a metal plate; Since it is integrally molded in a protruding inward shape from a metal plate, it is possible to reduce the thickness of the tube and the wall thickness as compared with the case of using a heat exchange tube made of a hollow extruded shape, The entire heat exchanger can be made compact.

Further, a plurality of communication holes through which the parallel fluid passages pass are formed in each reinforcing wall, and an opening ratio, which is a ratio occupied by all the communication holes in each reinforcing wall, is in a range of 10 to 40%. The fluid flowing through the parallel fluid passages flows in the width direction of the heat exchange tubes through the communication holes and is mixed over all the fluid passages, so that there is no temperature difference between the fluid passages. Heat exchange efficiency is improved. Moreover, since the opening ratio, which is the ratio of all communication holes in each reinforcing wall, is in the range of 10 to 40%,
The thermal conductance increases, and the heat exchange efficiency further improves.

[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 up, down, left, and right in FIGS. 2, 5, 7, 7, 9, 12, 14, 16, 18, and 22 are respectively referred to as up, down, left, and right. However, for the description related to FIG.
The vertical and horizontal directions in FIG. The term “aluminum” includes an aluminum alloy in addition to pure aluminum.

FIG. 1 shows the overall configuration of a condenser to which the heat exchanger according to the present invention is applied, and FIGS. 2 to 4 show the refrigerant flow tubes (heat exchange tubes).

In FIG. 1, the condenser has an inlet header (1) and an outlet header (2) which are arranged parallel to each other at an interval from each other, and both ends are connected to both headers (1) and (2), respectively. Parallel flat refrigerant flow pipe (3) (Heat exchange pipe)
And aluminum corrugated fins (4) that are placed in the ventilation gap between adjacent refrigerant flow pipes (3) and brazed to both refrigerant flow pipes (3), and the peripheral wall of the inlet header (1) An inlet pipe (5) connected to the upper end and an outlet pipe (6) connected to the lower end of the peripheral wall of the outlet header (2).
The gas-phase refrigerant flowing from (5) into the inlet header (1) is diverted to each refrigerant flow pipe (3), flows to the right, reaches the outlet header (2), and flows through the outlet pipe (6) into the liquid phase. It is supposed to flow out.

As shown in FIGS. 2 to 4, the refrigerant flow pipe (3)
Consists of flat upper and lower walls (7) (8) (rectangular wall) and upper and lower walls (7)
Left and right side walls of double structure (9) (1
0) and a plurality of reinforcing walls (11) extending between the left and right side walls (9) and (10) and extending in the longitudinal direction and extending at a predetermined distance from each other, extending over the upper and lower walls (7) and (8). , An aluminum flat tube (T1) having a parallel fluid passage (12) inside
Consists of The flat tube (T1) consists of the lower wall (8), the left and right side walls (9) (1
0) and an aluminum plate-shaped lower component (13) constituting the reinforcing wall (11), and an aluminum plate-shaped upper component (14) constituting the upper wall (7) and the left and right side walls (9) and (10). ).

The left and right side walls (9) and (10) have a hanging wall (15) formed integrally with the left and right side edges of the upper wall (7), and a rising part formed integrally with the left and right side edges of the lower wall (8). The wall (16) and the hanging wall (15)
Are brazed to each other in an overlapping state so that they are on the outside. The lower end of the hanging wall (15) is the lower wall
(8) It extends downward and is bent inward to form the inclined surface (1) formed on the left and right side edges of the lower surface of the lower wall (2).
7) is engaged and brazed.

The reinforcing wall (11) is formed by joining a reinforcing wall forming portion (18) formed integrally with the lower wall (8) to the inner surface of the upper wall (7). The pitch of the reinforcing wall (11) in the pipe width direction is preferably 4 mm or less, and the height of the reinforcing wall (11) is preferably 2 mm or less. In addition, the reinforcement wall (1
1) is provided with a plurality of communication holes (19) through which the parallel fluid passages (12) pass. The communication holes (19) are arranged in a zigzag pattern when viewed from a plane. When the communication holes (19) are provided, the fluid flowing through the parallel fluid passages (12) flows in the width direction of the flat tube (T1) through the communication holes (19), and all the fluid passages (12 ), And mixed in the fluid passage (1
There will be no temperature difference in the fluid between 2). Therefore, the heat exchange efficiency is improved. The opening ratio, which is the ratio of all communication holes (19) in each reinforcing wall (11), is 10 to 4
It is preferably in the range of 0%, particularly 10-30%, and more preferably in the range of 15-20%. In this case, the thermal conductance increases and the communication hole (19)
The effect of improving the heat exchange efficiency due to the formation of is remarkable. The communication hole (19) is formed by notches (20) formed at predetermined intervals on the upper edge of the reinforcing wall forming portion (18) by closing the opening portion by the upper wall (7). Things. In this case, the communication holes (1
9) is staggered when viewed from above, so the flat tube (T
In the width direction of 1), there is a joint between the two constituent members (13) and (14), and sufficient joint strength is secured.

In the condenser described above, the inlet pipe (5)
In order for the fluid that has flowed into the inlet header (1) to flow through all the refrigerant flow pipes (3) in the same direction to the outlet header (2), and to be discharged from the outlet pipe (6), Refrigerant distribution pipe (3)
May be set to appropriate numerical values.

The above-described minimum flow path cross-sectional area X and equivalent diameter Y
Means the following.

That is, the reinforcing wall (11) of the refrigerant flow pipe (3)
In addition, when the plurality of communication holes (19) are formed in a staggered arrangement when viewed from a plane, the refrigerant flow pipe (3) in a portion where the communication holes (19) exist in the reinforcing walls (11) at both left and right ends is provided. The cross-sectional view is as shown in Fig. 5 (A).
FIG. 5B is a cross-sectional view of the portion of the refrigerant flow pipe (3) where (19) is not present. In FIGS. 5A and 5B, the flow path cross-sectional area is the total area of the hatched portions. By the way, as can be seen from FIGS. 5A and 5B, the cross-sectional area of the flow path in FIG. 5B is smaller than the cross-sectional area of the flow path in FIG. The cross-sectional area of the flow path in B) is referred to as a minimum cross-sectional area X.

Further, the value obtained by multiplying the minimum flow path cross-sectional area X by four and dividing it by the wetting perimeter in FIG.
It is assumed that. The wet perimeter in FIG.
In this figure, the total length of the portion indicated by the thick line, that is, the portion in contact with the fluid is referred to.

The flat tube (T1) constituting the refrigerant flow tube (3)
Is manufactured as follows.

First, a plate-shaped aluminum lower component (13) as shown in FIG. 6 is formed by rolling, and a plate-shaped aluminum upper component (14) is formed by roll forming.

The lower component (13) comprises a flat lower wall forming part (21).
The rising wall (16) integrally formed on both side edges of the lower wall forming portion (21) and the rising wall (16) of the lower wall forming portion (13) in a rising shape and at a predetermined interval from each other. And a plurality of reinforcing wall forming portions (18) extending integrally in the longitudinal direction, and a trapezoidal cut is formed on the upper edge of the reinforcing wall forming portion (18) at predetermined intervals in the length direction. The notches (20) are formed in a staggered arrangement when viewed from a plane. An inclined surface (17) that is inclined upward and outward in the left-right direction is formed at the left and right side edges on the lower surface of the lower wall forming portion (21) of the lower component member (13).
The height of both rising walls (16) of the lower component (13) is equal to the height of the reinforcing wall forming portion (18). The lower component (13)
It is made of an aluminum brazing sheet having a brazing material layer (not shown) on the outer surface, that is, the lower surface of the lower wall forming portion (21) and the outer surface of the both rising walls (16).

The upper component (14) comprises a flat upper wall forming part (22).
And a hanging wall integrally formed on both side edges of the upper wall forming portion (22)
(15). The width of the upper wall forming portion (22) of the upper component (14) is slightly larger than the width of the lower component (13), and the lower component (13)
Is to be covered. The hanging length of both hanging walls (15) of the upper component (14) is
6) It is slightly larger than the height. Upper component (14)
Consists of an aluminum brazing sheet having a brazing material layer (not shown) on both surfaces, that is, on both upper and lower surfaces of the upper wall forming portion (22), and on both inner and outer surfaces of both hanging walls (15).

Next, after the upper and lower structural members (14) and (13) are subjected to a degreasing treatment, a brazing flux is applied thereto.

Next, the upper component (14) is replaced with the lower component (13).
After the lower component (13), the portion of the both hanging walls (15) of the upper component (14) protruding downward from the upstanding walls (16) of the lower component (13) is bent inward to be bent downward. 13) slope (1
7), and both components (14) and (13) are temporarily fixed while applying force from above and below.

Then, the two members (14) and (13) temporarily fixed are heated to the brazing temperature. Then, the lower component (13)
The upper wall forming part of the upper component (14) is at the upper end
(22) The lower wall is brazed to both left and right ends of the lower surface, and the upper end of the reinforcing wall forming portion (18) is brazed to the lower surface of the upper wall forming portion (22) of the upper component (14). Further, the hanging wall (15) of the upper component (14) and the rising wall (16) of the lower component (13) are brazed and the lower end of the hanging wall (15) of the upper component (14) is bent. The bent portion is brazed to the inclined surface (17) of the lower component member (13) with a lap joint. Thus, the flat tube (T1) is manufactured.

In the above-described embodiment, the case where the heat exchanger according to the present invention is applied to a condenser is shown. However, when the heat exchanger is applied to an evaporator, for example, the refrigerant flow pipe (3) faces in a vertical direction. It is used as follows.

FIG. 7 shows a first modification of the aluminum flat tube constituting the refrigerant flow tube (3).

In FIG. 7, an aluminum flat tube (T2)
In the upper wall (7), a plurality of ridges (30) extending in the longitudinal direction are formed integrally with the inner surface of the upper wall (7) in a downwardly protruding shape to increase the heat transfer area, and the inner wall of the lower wall (8) is adjacent to the inner wall. A plurality of projections (31) are integrally formed in a protruding shape at intervals in the length direction in a portion between the reinforcing walls (11) in order to increase a heat transfer area. Other configurations are the same as those shown in FIGS.

The flat tube (T2) is manufactured as follows.

First, a plate-shaped aluminum lower component (13) and a plate-shaped aluminum upper component (14) as shown in FIG. 8 are formed by rolling.

The lower component (13) is formed by integrally forming a projection (31) on the upper surface of the lower wall forming portion (21).
On the lower surface of the upper wall forming portion (22), a plurality of ridges (30) extending in the length direction are spaced apart in the left-right direction and are integrally formed in a downward protruding shape over the entire width except for a predetermined width portion at both left and right ends. It is formed in. Therefore, on the lower surface of the upper wall forming portion (22), at least one ridge (30) exists at a portion corresponding to each reinforcing wall forming portion (18) of the lower component (13).
The protruding height of the ridges (30) is preferably about 10 to 200 μm. This is due to the adjacent notches in the reinforcement wall formation (18).
(20) Due to various differences in the height position of the upper edge of the portion (32), the size of the gap existing between the upper component (14) and the upper wall forming portion (22) of the lower surface is reduced. If it is smaller than 10 μm, and if it is smaller than 10 μm, both constituent members (1
3) During the temporary fixing in (14), the upper end of the reinforcing wall forming portion (18) of the lower component (13) may not contact the ridge (30) in some cases.
If it is higher than 0 μm, it may be impossible to temporarily fix both the constituent members (13) and (14). Since the ridge (30) is formed simultaneously with the rolling of the upper component (14), the ridge (30)
The thickness of the brazing material layer in some parts is thicker than in other parts. Other configurations of the upper and lower components (14, 13) are shown in FIGS.
Are the same as those shown in FIG. Then, the flat tube (T1) shown in FIGS. 2 to 4 is manufactured in the same manner as the flat tube (T1).

However, after the upper component member (14) is fitted over the lower component member (13), the both rising walls (16) of the lower component member (13) in the both hanging walls (15) of the upper component member (14). ) Is bent inward to project the portion below, and the inclined surface (17) of the lower component (13).
When the two members (14) and (13) are temporarily fixed with a force applied from above and below, the portion (32) between the adjacent notches (20) in the reinforcing wall forming portion (18) is Upper wall forming part (22) of upper component (14) due to different height positions of the upper edge
Each part (32) even if there is a gap between
The upper edge closely contacts the ridges (30) on the lower surface of the upper wall forming portion (22). If the size of the gap is smaller than the protruding height of the ridge (30), the ridge (30) is deformed. In addition, both components
(14) When the temporarily fixed (13) is heated to the brazing temperature, the reinforcing wall forming portion (18) of the lower component (13) has a raised ridge (30).
Brazed to The thickness of the brazing material layer at the ridge (30) is
Because it is thicker than the other parts, the molten brazing material is easily drawn to this part during brazing, and the gap between the upper surface of the reinforcing wall forming part (18) and the two ridges (30) Is also blocked. Thus, the flat tube (T2) is manufactured.

FIGS. 9 and 10 show a second modification of the aluminum flat tube constituting the refrigerant flow tube (3).

9 and 10, an aluminum flat tube (T3) is an aluminum plate-shaped lower component constituting a lower wall (8), left and right side walls (35) and (36) and a reinforcing wall (11). (3
7) and an upper component (38) made of a flat aluminum plate constituting the upper wall (7).

The left and right side walls (35) and (36) are formed by joining a rising wall (39) integrally formed with the lower wall (8) to a flat upper wall (7).

Communication holes (19) formed in a plurality of reinforcing walls (11)
The rectangular notches (40) provided at predetermined intervals on the upper edge of the reinforcing wall forming portion (18) are formed by closing the open portions with the upper wall (7). .

The flat tube (T3) is manufactured as follows.

First, as shown in FIG. 11, a lower wall forming portion (41) and both side edges of the lower wall forming portion (41) are integrally formed by rolling from an aluminum brazing sheet having one surface covered with a brazing material layer. A plurality of reinforcements extending in the length direction integrally formed at a predetermined interval from each other in the rising wall (39) and the rising wall (39) of the lower wall forming portion (41). A rectangular notch (40) is formed on the upper edge of the reinforcing wall forming portion (18) at a predetermined interval in the longitudinal direction thereof so that the notch (40) is staggered when viewed from a plane. The formed lower component (37) is formed. Both rising walls of the lower component (37) (3
9), a thin portion (39b) is provided via a step (39a). The lower surface of the lower wall forming portion (41) of the lower component member (37) and the outer surface of the rising wall (39) are formed of a brazing material layer (not shown).
Covered with.

Further, a flat upper component member (38) is formed from an aluminum brazing sheet having both surfaces covered with a brazing material layer. The upper surfaces of both side edges of the upper component member (38) are inclined surfaces (38a) inclined downward and outward. Then
Both edges of the upper component (38) are placed on the step (39a) of the rising wall (39) of the lower component (37), and the thin portion (39b) is bent to form an inclined surface of the upper component (38). (38a) Adhere on top. Next, the rising wall (39) of the lower component (37) and the tip of the reinforcing wall forming portion (18) are brazed to the upper component (38). Thus, the flat tube (T3) is manufactured.

FIG. 12 shows a third modified example of the aluminum flat tube constituting the refrigerant flow tube (3).

In FIG. 12, an aluminum flat tube (T
The left side wall (45) of (4) is formed integrally with the left side wall (45a) of the upper wall (7), which is downwardly formed integrally with the left side edge of the upper wall (7). Left upward wall forming part (4
5b) is formed by brazing the end portions of each other with an abutting shape, and the outer surface thereof has an arc-shaped cross section. The butted portion of the left side wall forming portions (45a) (45b) is oblique in cross section to increase the brazing area. The right side wall (46) is formed integrally with the upper wall (7) and the lower wall (8), and has a circular arc shape projecting outward in the cross section as a whole. The reinforcing wall (47) has a downward reinforcing wall forming portion (47a) integrally formed in a hanging manner with the upper wall (7), and an upward reinforcing wall forming portion (47b) integrally formed in a rising shape on the lower wall (8). ) Are formed by brazing the end portions with each other. The communication hole (48) is the upper wall (7)
A pair of notches (a pair of notches (4) provided at the lower edge of the downward reinforcing wall forming portion (47a) and the upper edge of the upward reinforcing wall forming portion (47b) of the lower wall (8) are provided at intervals in the longitudinal direction. It is formed by combining 48a) and (48b). Also in this case, the communication holes (48) formed in the plurality of reinforcing walls (47) are in a staggered arrangement when viewed from a plane. The opening ratio, which is the ratio of all the communication holes (48) in each reinforcing wall (47), is 10 to 10.
40%, preferably 10-30%, desirably 15-2
0%.

In the flat tube (T4), one plate-shaped component member made of an aluminum brazing sheet having brazing material layers on both sides is bent into a hairpin shape at the center of the width, and both left wall forming portions (45a) (45a) 45b) Part and reinforcement wall forming part (47a)
(47b) It is formed by brazing in a butted state.

The flat heat exchange tube (T4) is manufactured as follows.

First, an aluminum brazing sheet having a brazing material layer on both sides is rolled to form an upper wall forming portion (49) as shown in FIG.
(50), the lower wall forming part (51), and the left side wall forming part (45a) (45
b), and a plurality of upper and lower wall forming portions (49), (51) integrally formed in an upwardly protruding shape so as to be symmetrical about the connecting portion (50) and having notches (48a) (48b). A plate-shaped component member (52) including the reinforcing wall forming portions (47a) (47b) is formed by rolling.

Next, after the component (52) is subjected to a degreasing treatment, a flux for brazing is applied. Then the components
(52) is bent into a hairpin shape at the connecting portion (50), and the left side wall forming portions (45a) (45b) and the reinforcing wall forming portions (47a) (47b) are butted together and brazed. Thus, the flat tube (T4) is manufactured.

FIG. 14 shows a fourth modification of the aluminum flat tube constituting the refrigerant flow tube (3).

In FIG. 14, an aluminum flat tube (T
In the reinforcing wall (55) in (5), a downward reinforcing wall forming portion (55a) integrally formed in an inwardly protruding shape from the upper wall (7) has a lower wall (8).
An upper reinforcing wall forming portion (55b) integrally formed in an inwardly protruding shape from the lower wall (8), which is formed by being joined to the inner surface.
There are two types, one that is joined to the inner surface of the upper wall (7),
Both are arranged alternately. The communication hole (56) is formed at the lower edge of the downward reinforcing wall forming portion (55a) and the upward reinforcing wall forming portion.
Notches (56a) and (56b) provided at the upper edge of (55b) at predetermined intervals in the length direction respectively, and the opening of one of the upper and lower walls (7) and (8) is closed. It is formed by being done. Also in this case, the communication holes formed in the plurality of reinforcing walls (55)
(56) is staggered when viewed from the plane. Further, the opening ratio, which is the ratio of all the communication holes (56) in each reinforcing wall (55), is also 10 to 40%, preferably 10 to 30%.
%, Desirably 15 to 20%. Other configurations are
This is the same as the flat tube (T4) of the third modification.

The flat heat exchange tube (T5) is manufactured as follows.

First, an aluminum brazing sheet having a brazing material layer on both surfaces is rolled to form an upper wall forming portion (49) as shown in FIG.
(50), the lower wall forming part (51), and the left side wall forming part (45a) (45
b), and upper and lower wall forming portions (49), (51) are integrally formed in an upwardly protruding shape so as to be shifted by a half pitch to the left and right about the connecting portion (50), and the cutout portions (56a) (56b) Plate-shaped component member (57) including a plurality of reinforcing wall forming portions (55a) and (55b) having
To form

Then, after the component (57) is subjected to a degreasing treatment, a flux for brazing is applied. Then the components
(57) is bent into a hairpin shape at the connecting portion (50), the left side wall forming portions (45a) and (45b) are joined together and brazed, and the tips of the reinforcing wall forming portions (55a) and (55b) are connected to the upper and lower walls. Forming part (49)
Braze to either one of (51). Thus flat tube (T5)
Is manufactured.

FIG. 16 shows a fifth modification of the aluminum flat tube constituting the refrigerant flow tube (3).

In FIG. 16, an aluminum flat tube (T
The reinforcing wall (60) of (6) is formed by joining a downward reinforcing wall forming portion (60a) integrally formed in an inwardly protruding shape from the upper wall (7) to the inner surface of the lower wall (8). It is. The communication hole (61) has a notch (61a) provided at a lower edge of the downward reinforcing wall forming portion (60a) at predetermined intervals in the length direction, and an opening thereof is closed by the lower wall (8). It is formed by peeling. Again,
The communication holes (61) formed in the plurality of reinforcing walls (60) are arranged in a staggered arrangement when viewed from a plane. Also, the opening ratio, which is the ratio of all the communication holes (61) in each reinforcing wall (60), is 1
0-40%, preferably 10-30%, desirably 15
~ 20%. Other configurations are the same as those of the flat exchange tube (T5) of the fourth modified example.

The flat tube (T6) is manufactured as follows.

First, an aluminum brazing sheet having a brazing material layer on both surfaces is rolled to form an upper wall forming portion (49) as shown in FIG.
(50), the lower wall forming part (51), and the left side wall forming part (45a) (45
b) and a plate-shaped component member (62) having a plurality of reinforcing wall forming portions (60a) integrally formed in the upper wall forming portion (49) in an upwardly protruding shape and having notches (61a). .

Next, after the component (62) is subjected to a degreasing treatment, a flux for brazing is applied. Then the components
(62) is bent into a hairpin shape at the connecting portion (50), the left side wall forming portions (45a) and (45b) are joined together by brazing, and the tip of the reinforcing wall forming portion (60a) is joined to the lower wall forming portion (60). Braze to 51). Thus, the flat tube (T6) is manufactured.

FIG. 18 shows a sixth modified example of the aluminum flat tube constituting the refrigerant flow tube (3).

In FIG. 18, an aluminum flat tube (T
The right side wall (65) of (7) is formed integrally with the right side edge of the upper wall (7) in a downward facing right side wall forming part (65a), and the right side edge of the lower wall (8) is formed integrally with the right side edge of the lower wall (8). Right side wall forming part (6
5b) is formed by brazing the tips of the ends with each other. Other configurations are the same as those of the flat tube (T4) of the third modified example. Therefore, this flat tube
(T7) is an upper wall forming part (66), a downward left and right side wall forming part (45a)
(65a) and an upper component (67) having a plurality of downward reinforcing wall forming portions (47a) having notches (48a); and a lower wall forming portion.
(68), left and right side wall forming parts (45b) (65b), and notch
(48b) and a lower component (69) provided with a plurality of upward reinforcing wall forming portions (47b).

The flat heat exchange tube (T7) is manufactured as follows.

First, upper and lower structural members (67) and (69) as shown in FIG. 19 are formed by rolling from an aluminum brazing sheet having a brazing material layer on both surfaces.

Then, after the upper and lower structural members (67) and (69) are subjected to a degreasing treatment, a flux for brazing is applied. afterwards,
The left and right side wall forming portions (45a) (45b) (6
5a) (65b), and reinforcing wall forming portions (47a) (47b)
Butt the ends of the pieces together and braze. Thus, a flat heat exchange tube (T7) is manufactured.

[0068]

Examples and Comparative Examples Hereinafter, examples of the present invention will be described together with comparative examples.

EXAMPLE A flat tube (T1) shown in FIGS.
mm, width 18mm, thickness 1.7mm, number 1 of reinforcing walls (11)
7. The pitch of the reinforcing wall (11) is 1.05 mm, the thickness of the reinforcing wall (11) is 0.4 mm, the height of the reinforcing wall (11) is 1.3 mm, and the communication hole (1
9) Pitch 2.18 mm, opening ratio 16%, minimum flow path cross-sectional area 10.7 mm ² , refrigerant flow pipe with equivalent diameter 0.88 mm
A condenser as shown in FIG. 1 having 47 pieces of (3) is prepared, HFC134a of 59 ° C. is supplied to the inlet pipe (5), and cooling air is applied from the front, and after one hour, the temperature of the condenser is measured by thermography. The changes were examined. As a result, the temperature of all refrigerant flow pipes (3)
It gradually became lower from the (1) side to the outlet header (2) side, and it was found that HFC134a was flowing through all the refrigerant flow pipes (3). FIG. 20 schematically shows the result. In FIG. 20, the temperature of the capacitor is A → B → C
→ D → E → F.

Comparative Example As shown in FIG. 22, flat upper and lower walls (70) and (71)
(70) (71) The left and right side walls (72) (73) and the upper and lower walls (70)
It is made of an aluminum hollow extruded section provided with a reinforcing wall (74) extending over the (71) and extending in the length direction, and has a length of 720 mm, a width of 16 mm, a thickness of 3 mm, the number of the reinforcing wall (74) 3, and the reinforcement. Refrigerant whose wall (74) has a pitch of 3.35 mm, thickness of the reinforcing wall (74) is 0.5 mm, height of the reinforcing wall (74) is 2.5 mm, channel cross-sectional area is 24.1 mm ² , and equivalent diameter is 1.665 mm. It has 47 flow pipes (75). A condenser having the same structure as that shown in FIG. 1 is prepared as a whole. HFC134a at 59 ° C. is supplied to the inlet pipe, and cooling air is applied from the front for 1 hour. After the lapse of time, the temperature change of the capacitor was examined by thermography. As a result, the lower refrigerant flow pipe (75)
The temperature of the refrigerant flow pipes (7
In 5), it was found that the fluid stayed and did not flow toward the outlet header side. This result is schematically shown in FIG. In FIG. 23, the temperature of the capacitor is H → I → J
→ K → L in order.

The cross-sectional area of the flow path in the comparative example is the cross-sectional area of each refrigerant passage, that is, the total area of the hatched portions in FIG. 22, and the equivalent diameter is four times the cross-sectional area of the flow path. The value obtained by dividing this by the wetting perimeter is referred to as the equivalent diameter. The wetting perimeter in FIG. 22 refers to the total length of the portion indicated by the thick line in FIG. 22, that is, the portion in contact with the fluid.

[Brief description of the drawings]

FIG. 1 is a front view of a condenser to which a heat exchanger according to the present invention is applied.

FIG. 2 is a cross-sectional view of a flat tube constituting a refrigerant flow tube of the condenser of FIG.

FIG. 3 is a partially enlarged view of FIG. 2;

FIG. 4 is a sectional view taken along line IV-IV of FIG. 3;

FIG. 5 is a cross-sectional view of a refrigerant flow pipe illustrating a minimum flow path cross-sectional area and an equivalent diameter.

FIG. 6 is a partial perspective view illustrating a method of manufacturing the flat tube of FIG. 2;

FIG. 7 is a cross-sectional view showing a first modified example of a flat tube forming a refrigerant flow tube.

FIG. 8 is a partial perspective view illustrating a method of manufacturing the flat tube of FIG. 7;

FIG. 9 is a cross-sectional view showing a second modification of the flat tube constituting the refrigerant flow tube.

FIG. 10 is an enlarged sectional view taken along line XX of FIG. 9;

FIG. 11 is a partial perspective view illustrating a method of manufacturing the flat tube of FIG. 9;

FIG. 12 is a cross-sectional view showing a third modification of the flat tube constituting the refrigerant flow tube.

FIG. 13 is a partial perspective view of components used to manufacture the flat tube of FIG.

FIG. 14 is a cross-sectional view showing a fourth modification of the flat tube constituting the refrigerant flow tube.

FIG. 15 is a partial perspective view of components used to manufacture the flat tube of FIG.

FIG. 16 is a cross-sectional view showing a fifth modification of the flat tube constituting the refrigerant flow tube.

FIG. 17 is a partial perspective view of a component used for manufacturing the flat tube of FIG. 16;

FIG. 18 is a cross-sectional view showing a sixth modification of the flat tube constituting the refrigerant flow tube.

19 is a partial perspective view of upper and lower components used to manufacture the flat tube of FIG.

FIG. 20 is a view schematically showing a result of an example.

FIG. 21 is a front view showing a conventional capacitor.

FIG. 22 is a cross-sectional view of a refrigerant flow tube used in a comparative example.

FIG. 23 is a view schematically showing a result of a comparative example.

[Explanation of symbols]

 (1): Inlet header (2): Outlet header (3): Refrigerant flow pipe (heat exchange pipe) (7): Upper wall (rectangular wall) (8): Lower wall (rectangular wall) (9) ( 35) (45): Left wall (10) (36) (46) (65): Right wall (11) (47) (55) (60): Reinforced wall (12): Fluid passage (19) (48) (56) (61): Communication hole (T1) (T2) (T3) (T4) (T5) (T6) (T7): Flat tube

Claims (3)

[Claims] 1. An inlet header and an outlet header which are arranged in parallel at a distance from each other, and parallel heat exchange tubes having both ends connected to both headers, respectively, and flow into the inlet header. The fluid flows in all the heat exchange tubes in the same direction and reaches the outlet header,
A heat exchange tube has a pair of flat rectangular walls opposed to each other, two side walls spanning both side edges of the two rectangular walls, and a lengthwise extending and extending between the two side walls. A flat tube having a plurality of reinforcing walls provided at predetermined intervals and having parallel fluid passages therein, wherein the flat tube is formed of a metal plate; A plurality of communication holes are formed integrally with each other in a protruding shape, and a plurality of communication holes through which parallel fluid passages are formed are formed in each reinforcing wall. Heat exchangers that are in the% range. 2. The heat exchanger according to claim 1, wherein the aperture ratio is in a range of 10 to 30%. 3. The heat exchanger according to claim 1, wherein the aperture ratio is 15 to 20%.