JPH0961084A - Method for manufacturing inlet or outlet pipe for laminated heat exchanger - Google Patents

Abstract

(57) Abstract: [PROBLEMS] To provide a method for manufacturing an inlet pipe or an outlet pipe for a laminated heat exchanger, in which poor joining is unlikely to occur. In manufacturing an inlet or outlet pipe (21), one end of which is interposed between predetermined two plates and one end of which is communicated from the side is closed.
After the one end of the circular pipe 20 is expanded, the peripheral wall of the expanded part 22 is pressed from both sides to form the flat part 22a joined to the both plates, and the one end is closed.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a method of manufacturing an inlet pipe or an outlet pipe interposed between two predetermined plates of a laminated heat exchanger used for an evaporator for a car / air conditioner.

[0002]

2. Description of the Related Art U-shaped recesses for forming fluid passages and oval front and rear headers which are continuous with the front and rear ends of the U-shaped fluid passage and are deeper than the recesses for passage of fluids in the bottom wall are formed. A pair of plates and corrugated fins, which are overlapped with the open sides of the front and rear header forming recesses facing each other, are alternately combined, and are arranged at predetermined positions of all the plates, and the header forming recesses are provided. Either one of the front and rear header forming recesses in the pair of plates whose closing sides face each other is made shallower than the other header forming recess, and the inlet or outlet pipe of the inlet or outlet pipe is formed between the bottom walls of these shallow header forming recesses. The joining side end is interposed, and at least one joining flat portion having a fluid passage hole is provided at the joining side end of the inlet or outlet pipe to close the end side opening. By the whole is bonded, laminated heat exchanger in which a plurality of U-shaped flat tube portion and the front and rear headers are formed, conventionally known.

When manufacturing the inlet or outlet pipe for this laminated heat exchanger, the insertion side end portion of the inlet or outlet pipe is made flat in order to secure the joint area between the pipe and the plate. The flat part for joining was formed.

[0004]

In the above-mentioned conventional method for manufacturing an inlet or outlet pipe for a laminated heat exchanger, the area of the flat portion is determined by the diameter of the pipe, but the area of the flat portion is not sufficient, resulting in a defective joint. There was a problem that was likely to occur.

An object of the present invention is to provide a method for manufacturing an inlet pipe or an outlet pipe for a laminated heat exchanger, which is less likely to cause defective joints.

[0006]

According to the method for manufacturing an inlet or outlet pipe for a laminated heat exchanger according to the present invention, one end portion is interposed between two predetermined plates in the middle of the laminated heat exchanger, and the pipe is laterally disposed. A method of manufacturing an inlet or outlet pipe having a closed end opening for a laminated heat exchanger that is made to communicate with a header, wherein after expanding one end of a circular pipe, the peripheral wall of the expanded pipe is cut from at least one of both sides. By pressing, a flat portion joined to at least one of the both plates is formed and one end is closed.

[0007]

BEST MODE FOR CARRYING OUT THE INVENTION Next, embodiments of the present invention will be described with reference to the drawings.

In this specification, front and rear are referred to as the side where the inlet and outlet pipes are provided, and the opposite is the rear. Also, left and right shall be referred to backward.

FIG. 1 shows a laminated heat exchanger (1) which is a target of the method for manufacturing an inlet or outlet pipe of the present invention. The laminated heat exchanger (1) is made of aluminum (aluminum alloy). , And the corrugated fins (3) alternate with a pair of substantially rectangular intermediate plates (2A) (2B) (2C) whose peripheral edges are joined together and in which a fluid flow path is formed. Left and right side plates (4) are overlapped on both left and right sides, and inlet and outlet pipes (21) (21) are installed in the center of the heat exchanger (1) left and right. Has been.

The intermediate plates (2A) (2B) (2C) are the standard type intermediate plate (2A) and the intermediate plate (2) for forming the partition.
There are three types, B) and the intermediate plate (2C) for fixing the pipe.

At the center of the heat exchanger (1), as shown in FIG. 2, from the left, the standard type intermediate plate (2A), the left and right pipe fixing intermediate plates (2C) (2C), the left and right partitions The forming intermediate plates (2B) (2B), the left and right pipe fixing intermediate plates (2C) (2C), and the standard type intermediate plate (2A) are arranged in this order. Left standard type intermediate plate (2A)
And the left pipe fixing intermediate plate (2C) adjacent to this is a pair to form a fluid flow path inside,
Below, the right pipe fixing intermediate plate (2C) and the left partition forming intermediate plate (2B), the right partition forming intermediate plate (2B) and the adjacent left pipe fixing intermediate plate (2C) The right pipe fixing intermediate plate (2C) and the standard type intermediate plate (2A) are paired to form a fluid passage therein. A standard type intermediate plate (2A) is arranged in a portion other than that shown in FIG.

As shown in FIG. 3, the standard type intermediate plate (2A) has a U-shaped recess for forming a fluid flow path on one side thereof.
(8) and the bottom wall (9a) (10
Front and rear header forming recesses (9) and (10) in which a fluid passage hole (11) is formed are provided in a). Fluid channel forming recess
The (8) is provided with a plurality of U-shaped small flow path forming ridges (15) having a height approximately twice the depth of the recess (8). Each of the ridges (15) has a shape of a half of a U shape consisting of a straight line portion and a quarter arc portion connected to the straight line portion, and is a concave portion for forming a fluid passage when viewed from the front of the intermediate plate (2). A total of four ridges (15) are provided in parallel on the right half of (8), and a total of four ridges (15) adjacent to each ridge (15) on the right half are overlapped on the left half. Two ridges (15) are provided in parallel.

The standard type intermediate plate (2A) is provided with a partition (12) having the same height as the peripheral edge (13) from the upper end to the lower end. The standard type intermediate plate (2A) further includes a left intermediate plate (2A) on the left side, a right intermediate plate (2A) on the right side, and an upper end bent portion (16) bent at substantially right angles, respectively. Left and right bent part (1
7) and a bottom bent portion (18) are provided. The lower end bent portion (18) is bent at a substantially right angle by a depth equal to the depth of the header forming recesses (9) (10), and then further bent downward. The upper end bent portion (16) has an inverted U shape when viewed from the front of the intermediate plate (2A), and the lower end thereof is at substantially the same level as the lower ends of the front and rear header forming recesses (9) (10). .
Further, of the pair of left and right intermediate plates (2A), the right intermediate plate (2A) projects rightward by burring into the fluid passage hole (11) of the header forming recess (9) on the rear side. A rim (11a) is provided.

A pair of standard type intermediate plates (2A) (2A)
Are stacked so that the open sides of the recesses (8), (9) and (10) face each other, and the opposing partitions (12) and the peripheral edge portions (13) are butted against each other and joined. Has been done. At this time, each of the ridges in the fluid channel forming recess (8)
The front end of (15) is joined to the bottom wall of the fluid passage forming recess (8) of the facing intermediate plate (2A), and the left intermediate plate (2A)
The ridge (15) and the corresponding ridge (15) of the right intermediate plate (2A) form a U-shaped small channel (14) having a semi-circular turn portion.

The shape of the ridges provided on the intermediate plate (2A) is not limited to that of the above embodiment,
Various modifications can be made as long as parallel U-shaped small fluid flow paths are formed when the pair of intermediate plates (2A) (2A) are superposed on each other. In the intermediate plate (2A) shown in the above embodiment, since the ridges (15) are alternately positioned after the intermediate plates (2A) are superposed and symmetrical with each other in the longitudinal direction, the convex plate (2A) is provided on the intermediate plate (2A). The number of strips (15) is small, so the shape of the intermediate plate (2A) is simple,
The effect is that the molding is easy and the manufacturing cost can be reduced. Further, since the tips of the ridges (15) of the fluid channel forming recesses (8) of the intermediate plate (2A) are joined to the bottom walls of the recesses (8) of the opposing intermediate plate (2A), 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.

The intermediate plate (2B) for partition formation is shown in FIG.
As shown in FIG. 5, the standard type intermediate plate (2A) is different only in that the bottom wall (9a) of the front header forming recess (9) is not provided with a fluid passage hole. Left partition forming intermediate plate (2B) and right partition forming intermediate plate (2B)
Are arranged so that the closed sides of the recesses (8), (9) and (10) face each other.

The intermediate plate (2C) for fixing the pipe is shown in FIG.
And as shown in FIG. 4, the front header forming recess (25)
Is formed to have the same depth as the fluid channel forming recess (8), and the fluid passage hole (26) formed in the bottom wall of the front header forming recess (25) is formed in the rear header forming recess. The vertical length is shorter than the fluid passage hole (11) formed in (10), and the notch (19) is formed in the front part of the upper end bent part (16) of the intermediate plate (2C). The difference from the standard type intermediate plate (2A) is that it is provided. The mold for forming the plate fixing intermediate plate (2C) is the same as the standard type intermediate plate (2A), and it is not necessary to increase the plate mold.

Inlet or outlet pipe (21) (both pipes (21)
(21) is the same, and will be referred to as an inlet pipe below)
As shown in FIG. 5, a circular pipe (20) having a diameter of 12.7 mm (see FIG. 5a) is prepared, and one end of the circular pipe is first expanded (see FIG. 5b). Flattened to form the left and right flat portions (22a) that are joined to the plate fixing intermediate plates (2C) and (2C), and the fluid passage holes (23) are opened in these left and right flat portions (22a). (See FIG. 5c). The opening at the tip of the inlet pipe (21) is closed by a lid (24).

The inlet pipe (21) has a header forming recess (25).
The bottom walls (25a) (10a) of (10) are inserted between a pair of pipe fixing intermediate plates (2C) (2C) which are butted against each other. Since the notch (19) is provided in the front part of the upper end bent part (16) of the intermediate plate (2C), the upper end bent part
The inlet pipes (21) are connected to each other without interfering with the (16) and their positions are not displaced.
C) Can be inserted between. Moreover, since the notch (19) is reinforced by the inlet pipe (21), the strength of the upper end bent portion (16) does not decrease. And, the front side header forming recess of each pipe fixing intermediate plate (2C) (2C)
Bottom wall (25a) of (25) and left and right flat parts (22a) of inlet pipe (21)
And are joined. As a result, the fluid passage hole (23) formed in the left and right flat portions (22a) of the inlet pipe (21) is formed in the front header forming recess (2C) of each pipe fixing intermediate plate (2C) (2C).
Aligned with the fluid passage hole (26) made in 5), the inlet pipe
(21) communicates with the front header (6).

If the circular pipe (20) having a diameter of 12.7 mm is made flat as it is as in the conventional case, the flat surface is small and the contact surface between the inlet pipe (21) and the intermediate plate (2C) is small, Although it tends to cause poor joints, by providing the flat part (22a) on the expanded part (22), it is possible to widen the contact surface between the inlet pipe (21) and the intermediate plate (2C). It is possible to prevent the occurrence of a defective joint and leakage due to this.

As shown in FIGS. 2 and 6, in the fluid passage hole (26) of the intermediate plate (2C) for fixing the pipe, an edge portion (26) protruding toward the inlet pipe (21) by burring is provided.
a) is provided. And these protruding edges (26a)
Is fitted into a fluid passage hole (23) provided in the flat portion (22a) of the inlet pipe (21).

As shown in FIG. 6, all plates (2A)
Before stacking (2B) and (2C) together and brazing them together, use the caulking jig (31) to fix the intermediate plate (2C) for fixing the pipe.
It is preferable that the inlet pipe (21) and the inlet pipe (21) are caulked and joined in advance. The caulking jig (31) is for the fluid passage hole (26) of the intermediate plate (2C) and the fluid passage of the inlet pipe (21) from both the left and right outer sides of the left and right intermediate plates (2C) that sandwich the inlet pipe (21). It is forcibly inserted into the hole (23), and an insertion part (32) having a cross section slightly larger than both fluid passage holes (11C) (23) is provided at the tip of the rod-shaped part (33). The tip of the insertion portion (32) is a tapered taper portion (32a). The inlet pipe (21) is sandwiched from the left and right sides by the intermediate plate (2C) for fixing the pipe, and the fluid passage hole (26) of the intermediate plate (2C)
The projecting edge (26a) of the is the fluid passage hole (23) of the inlet pipe (21).
Inserted part of the caulking jig (31) into the both fluid passage holes (26) (23) from the outside of the intermediate plate (2C) while being fitted inside.
(32) is inserted, and the protruding edge portion (26a) of the fluid passage hole (26) of the intermediate plate (2C) is crimped to the edge portion of the fluid passage hole (23) of the inlet pipe (21). By this caulking work, the inlet pipe (21)
The intermediate plate (2C) and the intermediate plate are securely joined together, and the number of defective leaks can be reduced.

The inlet pipe (21) can be arranged at any position of the heat exchanger (1) while being sandwiched between the intermediate plates (2C) (2C) as shown in FIG. Therefore, when the position of the inlet pipe (21) is designated by the customer, it can be easily dealt with by changing the positions of the intermediate plates (2C) (2C) for fixing the pipe.

In the above description, the inlet pipe (21) is flattened on both the left and right sides, and the fluid passage holes (23) are formed on both the left and right sides. However, only one of the inlet pipes (21) is flattened for fluid passage. You may make it open a hole (23) and join this flat part (22a) to an intermediate plate (2C).

The plurality of pairs of intermediate plates (2A), (2A), (2
A) (2C), (2C) (2B), (2B) (2C), (2C) (2A), (2A) (2A) are recessed ((8) (9) (10) (25) The heat exchanger (1) has a plurality of U-shaped flat tube portions (5) and the flat tube portions thereof, with the open sides of the heat exchangers (1) being overlapped and joined together in layers.
Front and rear headers (6) and (7) connected to both upper and lower ends of the front and rear of (5) are formed. Adjacent pair of intermediate plates (2A) (2A), (2A) (2C),
Between (2C) (2B), (2B) (2C), (2C) (2A), (2A) (2A), the intermediate plate (2A) (2B) (2C) header forming recess (9) The bottom walls (9a) and (10a) of (10) and the bottom bent portions (18) are butted against each other, but at this time, in the header (7) on the rear side, the fluid passage hole (11) The protruding edges (11a) are fitted in the opposing fluid passage holes (11).

In the heat exchanger (1), the left inlet pipe
The fluid introduced from (21) flows into almost the center of the header (6) on the front side, and then each flat pipe section on the left of the center.
It flows in a U shape inside (5) and reaches the header (7) on the rear side.
Furthermore, make sure that the inside of each flat tube section (5) to the right of the center is U
It flows like a letter and reaches the front header (6). During this time, the fluids are mixed and discharged from the front header (6) through the pipe (21) for the right outlet. On the other hand, the air flows through the gaps where the corrugated fins (3) exist between the flat tubes (5) adjacent to each other in the heat exchanger (1) or between the flat tubes (5) and the side plate (4). , The fluid and air are efficiently heat-exchanged with each other through the wall surface of the intermediate plate (2) and the corrugated fins (3). When the fluid flows in each U-shaped flat tube portion (5), the fluid does not mix between the adjacent small fluid flow passages (14), and the fluid flow does not have a stagnant portion.
Flows in the flat tube section (5). Therefore, the gas-liquid separation is small because it stays in only one small fluid flow path (14), and the pressure loss of the fluid is not increased. 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.

[0027]

According to the method for manufacturing an inlet or outlet pipe for a laminated heat exchanger of the present invention, one end of a circular pipe is expanded, and then the peripheral wall of the expanded pipe is pressed from at least one of both sides. Since a flat part that is joined to at least one of both plates is formed,
The joining area between the inlet or outlet pipe and the plate is large, and poor joining is less likely to occur.

[Brief description of drawings]

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

FIG. 2 is an enlarged horizontal sectional view of a portion where an inlet pipe is provided.

FIG. 3 is a perspective view showing a standard type intermediate plate.

FIG. 4 is a perspective view showing main parts of an inlet pipe and a pipe fixing plate.

FIG. 5 is a perspective view showing a method for manufacturing an inlet or outlet pipe.

FIG. 6 is a perspective view showing a method of joining the inlet pipe and the intermediate plate.

[Explanation of symbols] (1) Stacked heat exchanger (2A) (2B) (2C) Intermediate plate (6) Front header (10) Round pipe (21) Inlet or outlet pipe (22) Expansion part (22a) Flat Department

Claims (1)

[Claims] 1. A laminated heat exchanger having one end interposed between two predetermined plates (2C) (2C) in the middle of the laminated heat exchanger (1) so as to communicate with the header (6) from the side. A method for manufacturing an inlet or outlet pipe (21) in which one end opening for a exchanger is closed, wherein after expanding one end of a circular pipe (20),
By pressing the peripheral wall of the expanded portion (22) from at least one of both sides, a flat portion (22a) joined to at least one of the both plates (2C) (2C) is formed and one end is opened. A method for manufacturing an inlet or outlet pipe for a laminated heat exchanger, which is characterized by being closed.