JP2852466B2 - Heat exchanger manufacturing method - Google Patents

Description

Description: BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a method for manufacturing a heat exchanger used for a cooling and heating device used for cooling in summer and for heating in winter, for example. In a cooling / heating device that heats and evaporates freon and the like used as a refrigerant for cooling in summer by the heat of combustion of an oil burner or a gas burner in winter, and uses the latent heat to heat the refrigerant, The present invention relates to a method of manufacturing a heat exchanger used for heating by combustion heat.

In this specification, the term “aluminum” includes an aluminum alloy in addition to pure aluminum.

2. Description of the Related Art As such a cooling and heating device, as shown in FIG. 9, a heat exchanger (40) for heating a refrigerant by a combustion gas,
A radiator (41), a sealed pipe (42) connecting the heat exchanger (40) and the radiator (41), and a refrigerant carrier provided in the middle of the sealed pipe (42) for forcibly circulating the refrigerant. (43) is used.

Conventionally, such heat exchangers for air conditioners have
As shown in Fig. 10, a through hole (51) extending in the axial direction of the combustion cylinder (50) is formed on the peripheral wall (50a) of the cylindrical combustion cylinder (50) made of an extruded aluminum material having an internal combustion chamber. A plurality of fins (52) extending in the length direction are formed on the inner surface of the peripheral wall (50a) of the combustion cylinder (50) at predetermined intervals in the direction.
Are formed integrally at predetermined intervals in the circumferential direction, and the straight pipe portions of the plurality of hairpin-shaped refrigerant flow pipes (53) are inserted into adjacent through holes (51), and each hairpin-shaped refrigerant flow pipe (5
3) was connected by a U-shaped connecting pipe (54), and a burner (55) was used at one end opening of the combustion cylinder (50).

Problems to be Solved by the Invention However, in the above-described conventional heat exchanger, the passage of the refrigerant is bent into a U-shape at the bent portion of the refrigerant flow pipe (53) and at the connecting pipe (54). However, there is a problem that the pressure loss increases. Further, there is a problem that the sectional area of the refrigerant passage is small.

Therefore, as a heat exchanger that solves the above problem, an aluminum cylindrical combustion cylinder and a plurality of refrigerant passages inside, and the combustion passage of the combustion cylinder is extended in the circumferential direction or the axial direction of the combustion cylinder. There has been proposed an aluminum arc-shaped tubular refrigerant passage member closely adhered to an outer peripheral surface and brazed to a combustion cylinder (Japanese Utility Model Laid-Open No. 63-97066). Although this heat exchanger can solve the above-mentioned problems with the conventional heat exchanger, it is considered that the following problems occur. That is, since the combustion cylinder has a cylindrical shape and the refrigerant passage member has an arc shape, in order to manufacture such a heat exchanger, many jigs having a complicated structure are required, and the jig is used. There is a problem that the fixing work between the combustion cylinder and the refrigerant passage member is troublesome.

Further, when fixed by the jig, the combustion cylinder and the refrigerant passage member cannot be completely brought into close contact with each other, and as a result, a gap is formed between the outer peripheral surface of the combustion cylinder and the refrigerant passage member in the manufactured heat exchanger. Inevitable. When such a gap exists, the heat transfer efficiency decreases. In addition, if the gap exists, when pitting occurs on the wall of the refrigerant passage member on the combustion cylinder side, refrigerant such as freon leaks into the gap and causes pitting on the combustion cylinder. As a result, the freon enters the combustion cylinder,
Freon and combustion gas react to generate toxic gas.

In order to solve the above-described problems, the present inventors have previously proposed a cylindrical combustion cylinder having a burner attached at one end, an aluminum heat transfer partition for closing the other end opening of the combustion cylinder, and a heat transfer partition. A method of manufacturing a heat exchanger including an aluminum flat tubular refrigerant passage member brazed to the front surface and having a plurality of refrigerant passages therein, and a high-temperature gas flow regulating member brazed to the rear surface of the heat transfer partition. Proposed (Japanese Patent Application No. 2-1438)
No. 19).

However, in the method of the prior proposal, since the joining area between the heat transfer partition and the flat tubular refrigerant passage member is large, if the precision of the parts is not particularly good, air pools are generated and the joining rate is reduced. .

An object of the present invention is to solve the above-mentioned problems of the prior art,
When brazing, a brazing jig with a simple structure may be used, and the number of brazing jigs is small.The fixing work with the jig is easy, and even if the precision of the parts is not good, the air An object of the present invention is to provide a method of manufacturing a heat exchanger that can significantly increase a joining rate, improve a heat transfer coefficient, and prevent generation of a toxic gas without causing accumulation.

Means for Solving the Problems A method for manufacturing a heat exchanger according to the present invention comprises a cylindrical combustion cylinder having a burner attached at one end, an aluminum heat transfer partition for closing the other end opening of the combustion cylinder, and a heat transfer partition. A method for manufacturing a heat exchanger comprising: an aluminum flat tubular refrigerant passage member brazed to the front surface and having a plurality of refrigerant passages therein; and a high-temperature gas flow regulating member brazed to a rear surface of the heat transfer partition. A plurality of air discharging and brazing filler grooves are provided in parallel on the rear wall surface of the flat tubular refrigerant passage member, and the front surface of the heat transfer partition is brazed to the rear wall surface of the refrigerant passage member. A method for manufacturing a heat exchanger, characterized in that:

According to the method of manufacturing a heat exchanger of the present invention, a brazing jig having a simple structure may be used for brazing, and the number of brazing jigs may be small, and the fixing work by the jig is simple. In the present invention, in particular, a large number of air discharging and brazing filler recesses are provided in parallel on the rear wall surface of the flat tubular refrigerant passage member, and the heat transfer partition walls are formed on the rear wall surface of the refrigerant passage member. Since the front surface is brazed, so-called surface joining can be made as close as possible to line joining, and even if the accuracy of the parts is not good, the joining rate will be greatly increased without generating air pockets. The heat transfer coefficient from the combustion drum to the refrigerant passage member via the heat transfer partition can be improved. Also, if pitting corrosion occurs in the refrigerant passage member,
Even if refrigerant such as freon leaks, pitting corrosion can be prevented from occurring in the combustion drum due to the presence of the heat transfer partition, so that the generation of toxic gas due to the reaction between freon and combustion gas can be prevented. It is.

Next, an embodiment of the present invention will be described with reference to the drawings.

In the following description, front and rear, left and right are based on FIG. 2, and the front indicates the upper side of FIG. 2 and the rear indicates the opposite side. Also, left means the left side of FIG. 2 and right means the opposite.

In FIGS. 1 to 5, a heat exchanger (1) has a horizontal tubular combustion cylinder (2) open at both ends, and is attached to the rear end of the combustion cylinder (2) and converts oil, gas and the like into fuel. A burner (B), a heat transfer partition (3) made of aluminum for closing a front end opening of the combustion cylinder (2), a hot gas passage (4) formed inside the heat transfer partition (3), and A plurality of refrigerant passages (6) extending in the vertical direction, and a large number of parallel air discharging and brazing filler grooves (7) on the surface of the rear wall (5a). A) a refrigerant passage member (5) consisting of a flat tube made of an extruded aluminum material brazed to the front surface of (5).

In addition, it is preferable that the depth of the concave streak (7) of the flat tubular refrigerant passage member (5) is 0.2 mm or less.

The combustion cylinder (2) includes a cylindrical portion (2a) and an expanding portion (2b) formed at the front end of the cylindrical portion (2a). The inside of the cylindrical portion (2a) is a combustion chamber (8). It has been done. The inner peripheral surface of the cylindrical portion (2a) is covered with a heat insulating material (21). A hot gas passage (4) is provided in the expanding portion (2b).

The heat transfer partition (3) is formed of a brazing sheet comprising a core material (3a) and a brazing material (3b) covering both surfaces of the core material (3a) as shown in FIG. Brazing sheet core material (3a) is zinc 0.9-1.4% by weight, manganese
It is formed of an aluminum alloy containing 1.0 to 1.5% by weight and chromium of 0.03 to 0.12% by weight, with the balance being aluminum and unavoidable impurities.

The skin material (3b) is made of an aluminum alloy brazing material containing 7.9 to 9.5% by weight of silicon, 0.4 to 0.5% by weight of iron, and 0.5 to 3% by weight of zinc, with the balance being aluminum and unavoidable impurities. The zinc content in the skin material (3b) is 0.9-1.4
Preferably it is in the range of weight%. Heat transfer partition (3)
The exhaust pipe (9) is connected to the upper end of the exhaust pipe.

The high-temperature gas passage (4) includes two high-temperature gas flow regulating members (11) made of an extruded aluminum material and arranged at predetermined intervals above and below.

Each high-temperature gas flow restricting member (11) includes a left and right side wall (11a) extending vertically, a rear wall (11b) connecting the rear edges of the left and right side walls (11a), and a left and right side wall (11a). An intermediate wall (11c) is provided to connect the central portions of the width of the intermediate wall (11c) between the rear wall (11b) and the intermediate wall (11c) and the front of the intermediate wall (11c). The first heat transfer fins (11d) and the second heat transfer fins (1d
1e) is provided integrally, and both adjacent heat transfer fins (11d)
(11e) Both heat transfer fins (11d) (11d)
Hot combustion exhaust gas flows through a passage portion (13) between e) and the left and right side wall portions (11a).

The pitch between adjacent heat transfer fins (11d) and (11e) of the lower hot gas flow regulating member (11) is smaller than that of the upper hot gas flow regulating member (11), 11
d) It is preferable that the number of (11e) is large and the heat transfer area is large.

The left and right side walls (11) of the upper and lower hot gas flow regulating members (11)
a) Gas between the rear ends reaches the rear edges of the left and right side walls (11a), and prevents exhaust gas from flowing out between the high-temperature gas flow regulating members (11) to the side. A leak prevention part (17) is provided. Each high-temperature gas flow regulating member (11)
The end of the second heat transfer fin (11e) is brazed to the heat transfer partition (3), and is fixed to the heat transfer partition (3) via a fixing member (16) extending vertically at both left and right side edges. The cylinder (2) is fixed to the rear surface of the rear wall (11b).
The front edge of a) abuts.

Therefore, the high-temperature combustion exhaust gas generated in the combustion chamber (8) passes through the communication port (30) formed between the upper and lower high-temperature gas flow regulating members (11) and enters the high-temperature gas passage (4). It is designed to flow in.

The fixing member (16) is formed of a brazing sheet made of a core material (16a) and a brazing material (16b) covering both surfaces of the core material (16a). The core material (16a) of the brazing sheet is made of an aluminum alloy containing 0.05 to 0.20% by weight of copper and 1.0 to 1.5% by weight of manganese, with the balance being aluminum and unavoidable impurities. Leather material (16b)
Is formed of an aluminum alloy brazing material containing 8.0 to 10.0% by weight of silicon and 0.2 to 0.5% by weight of iron, the balance being aluminum and unavoidable impurities.

The fixing member (16) has a substantially L-shaped cross section, and the heat transfer partition (3)
And a first portion (14) closely contacting the inner surface of the first portion (1).
And 4) a second portion (15) protruding rearward from the opposing edges. The second portion (15) is brought into close contact with the inner surfaces of the left and right side walls (11a) of the high temperature gas flow regulating member (11). The front edges of the left and right side walls (11a) are cut by the thickness of the first portion (14), so that no gap is formed between the second heat transfer fin (11e) and the heat transfer partition (3). It has become.

Further, a gas leakage preventing portion (17) is provided integrally with the first portion (14) and the second portion (15).
At the upper and lower ends of the second part (15), a rear protruding part (15a)
Are provided integrally, and the rear protruding portion (15a) contacts an end of the intermediate wall portion (11c).

In the second portion (15), a plurality of holes (18) are formed at predetermined intervals in the vertical direction, and these holes (1) are formed.
8), a projection (1) provided integrally with the heat transfer partition (3)
9) is brazed to the heat transfer partition (3) in a state of being fitted.

The projection (19) has a substantially L-shaped cross section, and a U-shaped cut is made in the heat transfer partition (3), and the portion surrounded by the cut is bent backward and bent toward the high-temperature gas flow regulating member (11). It is formed by: The hole (20) formed to form the projection (19) by the edge of the hole (18) on the high-temperature gas flow regulating member (11) side abutting against the rear bent portion (19a) of the projection (19). ) Is blocked.

In the hot gas passage (4), the upper end of the passage (13) of the upper hot gas flow regulating member (11), which is located above the upper hot gas flow regulating member (11), and the exhaust pipe ( 9), and a guide (31) for communicating with the high-temperature gas flow restricting member (11) on the lower side and on both left and right sides of the high-temperature gas flow restricting members (11). A guide path (32) for communicating the lower end of the passage portion (13) of the high temperature gas flow regulating member (11) with the exhaust pipe (9) is provided.

The upper and lower ends of the refrigerant passage member (5) are bent forward and horizontally, respectively, and their ends are connected to the header (22). The bent portion is indicated by (5b).
The lower header (22) is an inlet header, and a refrigerant inlet pipe (23) is connected to a left end thereof. The oil of the compressor is always dissolved in the refrigerant, and when the refrigerant is heated and vaporized, the oil gradually accumulates, and its viscosity and low heat transfer inhibit the refrigerant from vaporizing and circulating. An oil drain pipe (24) is connected to the right end of the side header (22).

The upper header (22) is an outlet header, and a refrigerant outlet pipe (25) is connected to a left end thereof. Both headers (2
Along the peripheral wall of 2), a long hole extending in the axial direction (26)
Is formed, and the bent portion (5b) of the refrigerant passage member (5) is formed.
Is inserted into the header (22) through the elongated hole (26) and brazed to the peripheral wall of the header (22). As shown in FIG. 5, both headers (22) are superimposed on both sides of a brazing sheet (22) in which both sides of a core material (22a) are covered with a brazing material (22b). The brazing sheet (22) is formed into a cylindrical shape to form a header material so that the inclined portions (28) overlap each other, and the header material is brazed. It is formed by doing. The brazing of the inclined portions (28) is performed simultaneously with the brazing of the header (22), the coolant passage member (5) and other members.

In such a configuration, the combustion gas of the burner (B) enters the high-temperature gas passage (4) through the communication port (30) formed between the upper and lower high-temperature gas flow regulating members (11), It flows upward in the passage portion (13) of the high-temperature gas flow regulating member (11), and is further discharged from the exhaust pipe (9) through the guide passage (31). Similarly, it flows downward in the passage portion (13) of the lower high-temperature gas flow regulating member (11), and is further discharged from the exhaust pipe (9) through the guide passage (32). The heat of the exhaust gas is transferred to the heat transfer partition (3) directly or via the heat transfer fins (11d) (11e) while flowing in the high-temperature gas passage (4), and the heat transfer partition (3) and the refrigerant passage The refrigerant is transmitted to the refrigerant flowing through the refrigerant passage (6) of the refrigerant passage member (5) through the peripheral wall of the member (5). The refrigerant is a burner (B)
Is heated and vaporized by the combustion heat of the air, and the latent heat is used to perform heating. At this time, the refrigerant is first heated in the lower part of the refrigerant passage member (5) and partially vaporized,
The inside of the refrigerant passage (6) naturally rises by the action of the vaporized refrigerant, and the whole is vaporized.

The pitch between adjacent heat transfer fins (11d) and (11b) of the lower hot gas flow regulating member (11) is made smaller than that of the upper hot gas flow regulating member (11). When the area is large, the amount of heat transfer to the refrigerant in the lower part is large, and the natural rising force is large.

Hereinafter, the fourth method of manufacturing the heat exchanger (1) will be described.
This will be described with reference to the drawings and FIGS. 6 to 8.

A flat tubular refrigerant passage member (5) having in advance a heat transfer partition (3) made of an aluminum brazing sheet, and a concave strip (7) for air discharge and brazing filler filling parallel to the surface of the rear wall (5a).
(See FIG. 4), a high-temperature gas flow regulating member (11), a fixing member made of an aluminum brazing sheet (16), a header material (29) formed by molding an aluminum brazing sheet into a cylindrical shape and having a long hole (26). Have prepared.

A projection (19) is formed on the heat transfer partition (3). Further, a hole (18) is formed in the fixing member (16).

Then, first, the protrusion (19) of the heat transfer partition (3) is passed through the hole (18) of the fixing member (16), so that the fixing member (16)
Is temporarily fixed to the heat transfer partition (3). At this time, protrusion (19)
The rear bent portion (19a) of the fixing member (16) comes into contact with the edge of the hole (18) of the fixing member (16) on the high-temperature gas flow regulating member (11) side, and the projection (19)
The hole (20) formed in the heat transfer partition (3) is closed in order to form.

Then, the left and right side walls (11a) are the second members of the fixing member (16).
The two high-temperature gas flow regulating members (11) are arranged so as to be in close contact with the outer surface of the portion (15). At this time, the rear protruding portions (15a) integrally provided at the upper and lower ends of the second portion (15) correspond to the ends of the intermediate wall portion (11c), and the gas leakage preventing portion (17) functions as the rear wall portion. (11b) and the intermediate wall (11c). Therefore, the high-temperature gas flow regulating member (11) is positioned in the left-right direction and the up-down direction by the fixing member (16).

After that, the coolant passage member (5) is arranged on the surface on the opposite side of the heat transfer partition (3), and the end of the bent portion (5b) of the long hole (26) of the header material (29) is inserted. Fix with an appropriate jig (not shown).

And the heat transfer partition (3) and the fixing member (16), the heat transfer partition (3) and the high temperature gas flow restricting member (11), the fixing member (16) and the high temperature gas flow restricting member (11), 3), the refrigerant passage member (5), the inclined portion (28) of the header material (29),
Then, the peripheral edges of the refrigerant passage member (5) and the long hole (26) are brazed, respectively.

In the present invention, in particular, a large number of air discharge and brazing filler recesses (7) are provided in parallel on the surface of the rear wall (5a) of the flat tubular refrigerant passage member (5), and the refrigerant passage member (5) is provided. ), The front surface of the heat transfer partition (3) is brazed to the surface of the rear wall (5a), so that the so-called surface joining can be made as close as possible to the line joining, even if the precision of the parts is not good. However, no air pool is generated. Thereby, the joining ratio can be greatly improved.

In addition, by the heating during the brazing step, zinc contained in the skin (3b) of the heat transfer partition (2) is diffused into the aluminum of the core (3a), and zinc is diffused for corrosion protection. A layer is formed.

Further, the heat exchanger (1) is manufactured by fixing the heat transfer partition (3) to the combustion copper (2).

In the above-mentioned embodiment, a large number of air discharging and brazing filler filling recesses (7) are provided in parallel on the surface of the rear wall (5a) of the flat tubular refrigerant passage (5). The position and number of the air-exhausting and brazing filler groove (7) are not particularly limited and are arbitrary.

In the embodiment, the zinc diffusion layer for anticorrosion is formed on the surface side of the heat transfer partition (3) by heating during the brazing step. In some cases, a galvanized layer (7) is also provided on the surface side of the tubular refrigerant passage member (5) for corrosion protection.

Advantageous Effects of the Invention As described above, the present invention provides a tubular combustion cylinder having a burner attached to one end, an aluminum heat transfer partition for closing the other end opening of the combustion cylinder, and brazing to the front surface of the heat transfer partition and A method for manufacturing a heat exchanger including an aluminum flat tubular refrigerant passage member having a plurality of refrigerant passages therein and a high-temperature gas flow regulating member brazed to a rear surface of a heat transfer partition, comprising: The present invention is characterized in that a large number of air discharging and brazing filler recesses are provided in parallel on the rear wall surface of the refrigerant passage member, and the front surface of the heat transfer partition is brazed to the rear wall surface of the refrigerant passage member. According to the method (1), a brazing jig having a simple structure may be used during brazing, and the number of the brazing jigs may be small, and the fixing work by the jig is easy.

In this invention, in particular, a large number of air discharging and brazing filler filling concaves are provided in parallel on the rear wall surface of the flat tubular refrigerant passage member, and the front surface of the heat transfer partition is provided on the rear wall surface of the refrigerant passage member. So that the so-called surface joining can be made as close as possible to the line joining, and even if the precision of the parts is not good, the air joining does not occur and the joining rate is greatly improved. At the same time, the heat transfer rate from the combustion drum to the refrigerant passage member via the heat transfer partition is improved.

Also, even if pitting occurs in the refrigerant passage member and refrigerant such as freon leaks, the presence of the heat transfer partition can prevent pitting from occurring in the combustion drum, so that freon and the like can be prevented. This has the effect of preventing the generation of toxic gas due to the reaction with the combustion gas.

[Brief description of the drawings]

1 is a partially cutaway perspective view of a heat exchanger manufactured by the method of the present invention, FIG. 2 is an enlarged horizontal sectional view of the same, FIG. 3 is an enlarged view of a main part of a flat tubular refrigerant passage member, and FIG. 2 is an enlarged view of a main part of FIG. 2, FIG. 5 is an enlarged cross-sectional view of a header portion, FIGS. 6 to 8 show a method of manufacturing a heat exchanger according to the present invention in the order of steps, and FIG. FIG. 7 is a partially enlarged perspective view showing the arrangement of the heat transfer partition, the high-temperature gas flow restricting member, and the fixing member before the temporary assembly. FIG. 7 shows the heat transfer partition, the refrigerant passage member, the high-temperature gas flow restricting member, and the header before brazing. 8 is a schematic sectional view showing a state after brazing, and FIG.
FIG. 9 is a block diagram showing a cooling and heating device, and FIG. 10 is a perspective view showing an example of a conventional heat exchanger. (1) ... heat exchanger, (2) ... tubular combustion cylinder, (3) ...
... heat transfer partition, (5) ... flat tubular refrigerant passage member, (5a)
… Rear wall, (6)… refrigerant passage, (7)… recess for air discharge and filling with brazing material, (11)… high temperature gas flow regulating member,
(B) ... burner.

──────────────────────────────────────────────────続 き Continued on the front page (58) Field surveyed (Int. Cl. ⁶ , DB name) B23K 1/00-3/08 F28D 7/00 F28F 1/02

Claims (1)

(57) [Claims] 1. A cylindrical combustion cylinder (2) having a burner mounted at one end, an aluminum heat transfer partition (3) for closing the other end opening of the combustion cylinder (2), and a front surface of the heat transfer partition (3). An aluminum flat tubular refrigerant passage member (5) having a plurality of refrigerant passages (6) therein, and a high-temperature gas flow regulating member (11) brazed to the rear surface of the heat transfer partition (3). A method of manufacturing a heat exchanger comprising the steps of: (a) forming a large number of air-exhausting and brazing filler grooves (7) in parallel on the surface of a rear wall (5a) of a flat tubular refrigerant passage member (5); Provided in
A method for manufacturing a heat exchanger, comprising brazing a front surface of a heat transfer partition (3) to a surface of a rear wall (5a) of the refrigerant passage member (5).