JPH0894274A - Accumulated type heat exchanger - Google Patents

Abstract

PURPOSE: To provide an accumulated type heat exchanger having enhanced heat exchange performance and reduced pressure loss by reducing the size of a gas-liquid separator. CONSTITUTION: First - eighth line protrusions 31, 32, 33, 34, 35, 36, 37, 38 are provide on a bottom wall 8a of a depression 8 for forming a liquid passage on each of plates 2. The first - eighth line protrusions 31, 32, 33, 34, 35, 36, 37, 38 partition interior of a flat tube, which is formed by putting a pair of the plates 2 together, into a plurality of small independent U-shaped fluid passages.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a laminated heat exchanger used for an evaporator for a car / air conditioner.

[0002]

2. Description of the Related Art Conventionally, as a laminated evaporator of this type, a U-shaped fluid passage forming recess and two header forming recesses connected to the ends thereof are provided on one surface of a substantially rectangular plate. The adjacent plates are stacked in a layered manner with their concave portions facing each other and joined to each other, whereby a plurality of U-shaped flat pipe portions as viewed from the front and a header that is connected to the end portions of each flat pipe portion Is formed, a fluid passage hole is formed in the bottom wall of each header forming recess, and fluid is allowed to flow through all the flat tube portions and the header portion.

After the flat tube portion is formed on the plate, a large number of projections (ribs) are provided obliquely with respect to the flow path direction for mixing and rectifying the refrigerant to improve the heat exchange performance.

[0004]

However, in the conventional single-tank type laminated evaporator, as the width of the evaporator is reduced, it is separated into a gas phase and a liquid phase while passing through the passage, and the heat is separated. There are problems that the exchange performance is deteriorated and that the pressure loss of the refrigerant is increased due to the presence of many protrusions (ribs).

An object of the present invention is to provide a laminated heat exchanger in which gas-liquid separation is reduced to improve heat exchange performance and pressure loss is reduced.

[0006]

According to the laminated heat exchanger of the present invention, a U-shaped fluid passage forming recess and two header forming recesses connected to the ends of the U-shaped fluid passage are formed on one surface of a substantially rectangular plate. Is provided, and adjacent plates are stacked in a layered manner with their concave portions facing each other and joined to each other, so that a plurality of U-shaped flat pipe portions and headers that are connected to the end portions of each flat pipe portion are provided. And a fluid passage hole is formed in the bottom wall of each header-forming recess, and a fluid flows through all the flat tube portions and the header portion. Of at least one of the plates is provided with a ridge for partitioning the inside of each flat tube portion into a plurality of independent U-shaped small fluid channels. .

[0007]

According to the laminated heat exchanger of the present invention, at least one of the adjacent plates has a concave portion for forming a fluid passage, and each flat pipe portion has a convex portion for partitioning into a plurality of independent U-shaped small fluid passages. Since the strips are provided, the fluids do not mix between the adjacent small fluid flow passages, and the fluids flow in the flat tube portion without causing a stagnant portion in the fluid flow. Therefore, gas-liquid separation is small because it stays in only one small flow path, and since there is no retention part, pressure loss of the fluid does not increase.

[0008]

Embodiments of the present invention will now be described with reference to the drawings.

In this specification, with respect to the front and back, the windward side is referred to as the front and the leeward side is referred to as the rear with reference to the direction of air flow (indicated by X in FIG. 1). Left and right of 2 is called left and right.

1 to 5 show a first embodiment in which the present invention is applied to a laminated evaporator (1) for a car air conditioner.

The laminated evaporator (1) is made of aluminum (including an aluminum alloy), and has a U-shaped fluid passage forming recess (8) and a concave portion (8) for forming the U-shaped fluid passage on one side of a substantially rectangular plate (2). Front and rear header forming recesses (10) connected to both front and rear upper ends
(9) are provided, and the adjacent plates (2) are stacked in layers with the recesses (8), (10) and (9) facing each other, and are joined to each other to form a plurality of U-shapes. Flat tube
(5) and a pair of front and rear header parts (7) and (6) connected to both front and rear upper ends of each flat tube part (5) are formed, and each header forming recess (1
A fluid passage hole (11) is made in the bottom wall (10a) (9a) of the (0) (9) to allow the fluid to flow in all the flat pipe sections (5) and the header sections (7) (6). It has been done. As shown in FIG. 1, at a position (indicated by J) about 1/3 from the left of the rear header part (6), fluid passage through the bottom wall (9a) of the rear header forming recess (9). The holes are not opened but are closed, and at a position (indicated by K) about 1/3 from the right of the front header part (7), the bottom wall (1) of the front header forming recess (10) is formed.
The fluid passage hole is not opened in 0a) and is closed.

Corrugated fins (3) are interposed between the flat tube portions (5) adjacent to each other. Side plates (19) are arranged on both left and right outer sides of the evaporator (1), and corrugated fins (3) are also interposed between each side plate (19) and the flat tube portion. The left end of the evaporator (1) is provided with a fluid introduction pipe (22) communicating with the rear header part (6), and the right end of the evaporator (1) is provided with a fluid discharge pipe (23) communicating with the front header part (7). ) Is provided. Both side plates (19) and each plate (2) are each made of aluminum brazing sheet.

Recesses (8) for forming fluid passages in each plate (2)
In the center of the plate, a fluid passage in the flat tube portion (5), which is long in the vertical direction and has the same height as the peripheral portion (13) of the plate (2), is formed.
A partition (12) having a character shape is provided from the upper end of the recess (8) to a portion closer to the lower end. At the lower end of each plate (2), there is provided a protrusion (14) for maintaining a space, which is equal in depth to the recesses (10) (9) for forming a header. Also adjacent plates
(2) On the plate (2) on the right side, the edge (11a) protruding to the right by burring is provided in the fluid passage hole (11) of the recess (9) for forming the header on the rear side. ing.
Then, between the adjacent plates (2), the partitions (12) facing each other of the pair of left and right plates (2) and the same peripheral portion (1
3) are abutted against each other and joined to each other, and in the plates (2) facing each other of the adjacent flat tube portions (5), the bottom wall (10a) (of the header forming recesses (10) (9) ( 9a) and the protrusions (14) for maintaining the gap are butted against each other and joined together, and in the rear header part (6),
Fluid passage hole where the protruding edge (11a) of the fluid passage hole (11) faces
It is fitted in (11).

Further, in the fluid channel forming recess (8) of each plate (2), a plurality of ridges (31) (32) (having a height approximately twice the depth of the recess (8) ( 33), (34), (35), (36), (37) and (38) are independent parallel U-shaped small fluid flow paths () in the flat tube section (5) after the adjacent plates (2) are superposed. A) (B) (C) (D) (E) (F)
It is provided so as to form (G) (H) (I).

That is, referring to FIG. 4, each ridge (31) (3
2) (33) (34) (35) (36) (37) (38) are straight parts (31a) (32a) (33
a) (34a) (35a) (36a) (37a) (38a) and the quarter arcs (31b) (32b) (33b) (34b) (35b) (36b) (37b) (38b) connected to this )
Each plate (2) has a first ridge (31) on the right half of the fluid channel forming recess (8) when viewed from the front of the plate. , The third ridge (33), the fifth ridge (35) and the seventh ridge (37) are provided in order from the inside, and the left ridge has the first ridge (31) when superposed. The second ridge (32) between the third ridge (33) and the fourth ridge (34) between the third ridge (33) and the fifth ridge (35) 5
The 6th ridge (36) between the ridge (35) and the 7th ridge (37) and the 8th ridge (38) outside the 7th ridge (37) are respectively from the inside. They are provided in order. Each ridge (31) (32) (33) (3
4) (35) (36) (37) (38), as shown in FIG. 3, the plate (2) adjacent to each other, U-shaped fluid flow path forming recesses (8) face each other When stacked in layers, each ridge (31) (32) (33) (34) (35) (36) (37) in the same recess (8)
The tip of (38) is joined to the bottom wall (8a) of the fluid channel forming recess (8) of the plate (2) facing each other, and the first ridge (31) of the left plate and the first ridge (31) of the right plate are connected to each other. The innermost U-shaped small fluid channel (A) is formed by 1 convex shape (31), and in the same manner, a total of 8 convex stripes (31) (32) (33) (34) By (35) (36) (37) (38), a total of nine parallel U-shaped small fluid channels (A) (B) (C) (D)
(E) (F) (G) (H) (I) are formed. Each small fluid channel (A) (B)
The turns of (C) (D) (E) (F) (G) (H) (I) are semi-circular.

Each small fluid channel (A) (B) (C) (D) (E) (F) (G) (H)
As shown in Fig. 5, the cross section of (I) has a square shape in order to ensure that the liquid is evenly distributed in the flat tube section (5) and the joint area between the flat tube section (5) and the fins (3) is secured. It has a close shape. In addition, regarding the cross-sectional area of each small fluid channel (A) (B) (C) (D) (E) (F) (G) (H) (I), the one inside (A) has the largest The outer one (I) is made the smallest, and the middle one (B) (C) (D) (E) (F) (G) (H) is made equal to each other or made larger inside. ing. That is, for the flow channel width, for example, (A) ≥ (B) ≥ (C) ≥ (D) ≥ (E) ≥
(F) ≥ (G) ≥ (H)> (I), and ">" is shown in at least one place. It may be ">" in all places. As a result, the flow velocities on the outside and inside are made uniform.

The front and rear corners of the lower end of each plate (2) have the same height as the peripheral edge (13) of the plate (2) and have a substantially triangular shape when viewed from the front of the plate (2). Reinforcing protrusions (15) are provided.

Further, as shown in FIG. 4, the height (indicated by P) of the inner edge of the recess (8) for forming a fluid flow path is higher than the height (indicated by Q) of the outer edge thereof.

6 and 7 show a second embodiment of the present invention.

In the plate (40) shown in FIG. 6, the fluid passage forming recesses (8A) of each plate (40) have a plurality of protrusions having a height approximately twice the depth of the recesses (8A). Articles (41) (42) (43) (44)
(45) (46) (47) (48) (51) (52) (53) (54) (55) (56) (57) (58) are provided and after the adjoining plates (40) are superposed. As in the first embodiment, independent parallel U-shaped fluid channels (A) (B) (C) (D) (E) (F) (G) (in the flat tube portion (5). H) (I) is formed, but its ridges (41) (42) (43) (44) (45) (46)
The shapes of (47) (48) (51) (52) (53) (54) (55) (56) (57) (58) are different. That is, in this embodiment, the straight line portion and the quarter arc portion of the ridge in the first embodiment are provided so as to be independent of each other, and each plate (40) has a fluid flow as viewed from the front of the plate. In the left half of the channel forming recess (8A), a first linear ridge (41), a third linear ridge (43), a fifth linear ridge (45) and a seventh linear ridge ( 47) is provided in order from the inside, and a second linear ridge between the first linear ridge (41) and the third linear ridge (43) when superposed on the right half. (42), the fourth linear ridge (44), the fifth linear ridge (45) and the fourth linear ridge (44) which are also between the third linear ridge (43) and the fifth linear ridge (45). Sixth linear ridges (46) located between the seven linear ridges (47) and an eighth linear ridge (48) located outside the seventh linear ridges (47)
, Each of which is provided in order from the inside, and the second straight ridge (42) is provided on the turn part of the left half when they are overlapped.
Second arcuate ridge (52), fourth straight ridge (44), fourth arcuate ridge (54), and sixth straight ridge (46), sixth arcuate ridge (56) and an eighth arcuate ridge (58) connected to the eighth straight ridge (48) are provided, and the first straight ridge (41 ) Connected to the first arc-shaped ridge (51), the third linear ridge (43) connected to the third arc-shaped ridge (53), the fifth linear ridge (45) connected to the fifth arc-shaped ridge. A seventh arcuate ridge (57) continuous with the line (55) and the seventh linear ridge (47) is provided.

Each ridge (41) (42) (43) (44) (45) (46) (47) (48)
In (51), (52), (53), (54), (55), (56), (57) and (58), the adjacent plates (40) face each other with the U-shaped fluid flow path forming recesses (8) facing each other. When the layers are stacked in this state, the same recess
Each ridge in (8) (41) (42) (43) (44) (45) (46) (47) (48)
(51) (52) (53) (54) (55) (56) (57) (58) The bottom wall (8a) of the fluid channel forming recess (8) of the plate (40) where the tips of the plates face each other. To be joined to. As a result, when the adjacent plates (40) are overlapped with each other, the U-shaped small fluid flow paths (A) (B) (C) (D) having the same shape as the first embodiment are arranged in parallel. (E) (F) (G) (H)
(I) is formed.

Also in this embodiment, the peripheral edges (13) of the plate (2) are provided at the front and rear corners of the lower end of each plate (2).
The front and rear reinforcing projections (17) and (16) having the same height as that of the plate (2) and having a substantially triangular shape when viewed from the front of the plate (2) are provided, but in this embodiment, as shown in FIG. Rear reinforcement protrusion (1
A burring hole (61) that projects inward is formed in 6), and a protruding edge of this burring hole (61) is formed in the reinforcing convex portion (17) on the front side when the adjacent plates are normally stacked. A receiving hole (62) into which the portion (61a) is fitted is opened. Therefore, the protruding edge portion (61a) of the burring hole (61) is fitted into the receiving hole (62), so that the plate (2)
Without crimping the peripheral part of the and with high accuracy, it prevents displacement during setting before brazing and in the furnace,
Brazing defects and internal circuit defects due to misalignment can be prevented. Then, in the header portion (6) on the rear side, the protruding edge portion (11a) of the fluid passage hole (11) is fitted into the opposing fluid passage hole (11), and the evaporator is combined.
It is possible to prevent the deviation of the entire core in (1).

Since the other points of the second embodiment are the same as those of the above-mentioned first embodiment, the same parts are designated by the same reference numerals in the drawings and their explanations are omitted.

The shape of the ridge provided on each plate (2) (40) is not limited to that of the first and second embodiments, and the adjacent plates (2) (40) are When stacked, the U-shaped small fluid flow paths in parallel (A)
Various modifications are possible as long as (B) (C) (D) (E) (F) (G) (H) (I) are formed. In the plates (2) (40) shown in the first and second embodiments, the ridges (31) (32) (33) (3
4) (35) (36) (37) (38) (41) (42) (43) (44) (45) (46) (47) (48)
(51) (52) (53) (54) (55) (56) (57) (58) are staggered after the adjoining plates (2) (40) are superposed and become symmetrical as a whole. Therefore, the number of ridges provided on each plate can be small, and therefore, the shape of each plate is simple, its molding is easy, and the manufacturing cost can be reduced. Also, the ridges (31) (32) (33) (34) (35) (3) of the U-shaped fluid flow path forming recesses (8) of the plates (2) (40)
6) (37) (38) (41) (42) (43) (44) (45) (46) (47) (48) (51) (52)
(53) (54) (55) (56) (57) (58) Plates with their tips facing each other
(2) Since it is joined to the bottom wall (8a) of the recess (8) of (40),
Since the joining area becomes large and the so-called point contact does not occur and the joining is performed by line contact, the pressure resistance strength increases.

In the first and second embodiments described above, the fluid (refrigerant) introduced into the header portion (6) at the rear side of the fluid introduction pipe (22) on the left side of the evaporator (1) is more It flows into the inside of 5). Fluid is in the rear header (6)
From the left to about 1/3 of the area (indicated by A) flows through each flat tube portion (5) in an inverted U shape, and the bottom wall (10a) of the front header forming recess (10) From the fluid passage hole (11) opened in (), proceed to the front header part (7) on the right side. During this time, the fluids are mixed and flow in the inside of each flat tube part (5) in an inverted U shape, and at the same location, the header forming concave part (9) on the rear side is formed.
From the fluid passage hole (11) formed in the bottom wall (9a) of the evaporator to the subsequent header part (6), and finally, the inside of the evaporator (1) flows in a meandering shape as a whole, and the front header It is discharged from the portion (7) to the fluid discharge pipe (28).

On the other hand, between the adjacent flat tube portions (5) of the evaporator (1) or between the flat tube portions (5) and the side plate.
Air flows through the gap between the corrugated fins (19) and the corrugated fins (3), and the wall of the plate (2) and corrugated fins
The fluid and air can be efficiently heat-exchanged via (3).

The fluid (refrigerant) enters the evaporator (1) in a gas-liquid separated state, for example, in a volume ratio of the gas 3 liquid 7. Therefore, in the rear header part (6), the liquid stays downward due to the difference in specific gravity, and flows into the flat pipe part (5) at a substantially uniform gas-liquid distribution ratio in the width direction. Fluid channel forming recess
Since the height of the inner edge (indicated by P in FIG. 4) of (8) is higher than the height of the outer edge (indicated by Q in FIG. 4), gas preferentially flows into the innermost small fluid flow path (A). Shed Flat tube section
In (5), the fluid boils and the vapor phase rate increases.

When the fluid flows through each U-shaped flat tube portion (5), the fluid flows in the adjacent small fluid channels (A) (B) (C) (D) (E) (F) (G).
There is no mixing between (H) and (I), and the fluid flows in the flat tube section (5) without any stagnant portion.
Therefore, gas-liquid separation is achieved with one small fluid flow path (A) (B) (C) (D)
Since it stays only in (E) (F) (G) (H) (I), it becomes smaller, and pressure loss of the fluid does not increase. In particular, the fluid flow in the turn portion becomes smooth, and the heat transfer coefficient can be improved. In addition, before and after the turn of the U-shaped flat tube (5), no stagnation or uneven flow is caused by the fluid flow, oil accumulation is prevented, and the difference in average temperature between the refrigerant and the outside air is reduced, The heat transfer coefficient is further improved.

The laminated heat exchanger according to the present invention is
It can be used not only for car cooler evaporators but also for other applications such as oil coolers, aftercoolers, and radiators.

[0030]

EFFECTS OF THE INVENTION According to the laminated heat exchanger of the present invention, gas-liquid separation is reduced because it is limited to one flow path.
Heat exchange performance is improved. Moreover, since there is no retention portion, the pressure loss of the fluid is not increased, and the width of the heat exchanger can be reduced.

Further, the ridge also has a function as a reinforcing wall, so that the pressure resistance is increased.

[Brief description of drawings]

FIG. 1 is a perspective view schematically showing an embodiment of a laminated heat exchanger according to the present invention.

FIG. 2 is a vertical cross-sectional view of the latter half of the heat exchanger.

FIG. 3 is a perspective view showing an embodiment of a plate constituting the heat exchanger.

FIG. 4 is an enlarged view of a main part with a plate cut away.

FIG. 5 is a sectional view of a channel.

FIG. 6 is an enlarged view of a main part with a part cut away showing a modified example of the plate.

7 is a sectional view taken along line VII-VII of FIG.

[Explanation of symbols]

 (1) Multilayer evaporator (2) Plate (5) Flat tube section (6) Rear header section (7) Front header section (8) Fluid channel forming recess (8a) Bottom wall (9) Rear header section Recess (9a) Bottom wall (10) Front header forming recess (10a) Bottom wall (11) Fluid passage hole (31) (32) (33) (34) (35) (36) (37) (38) ) Convex strip (40) Plate (A) (B) (C) (D) (E) (F) (G) (H) (I) U-shaped small fluid flow path

Claims (1)

[Claims] 1. A U-shaped fluid flow path forming recess and two header forming recesses connected to an end of the U-shaped fluid flow path forming recess are provided on one surface of a substantially rectangular plate, and adjacent plates face each other with the recess facing each other. A plurality of U-shaped flat pipe portions and a header portion continuous with the end portion of each flat pipe portion are formed by overlapping and joining each other in a layered state, and the bottom wall of each header forming recess is formed. In a laminated heat exchanger in which a fluid passage hole is formed in all flat tubes and headers so that a fluid can flow through at least one of a pair of adjacent plates A laminated heat exchanger characterized in that a convex strip for partitioning the inside of each flat tube portion into a plurality of independent U-shaped small fluid passages is provided on the bottom wall of the concave portion.