JPH03238165A - Production of tube for heat exchanger and production of heat exchanger using this tube - Google Patents

Abstract

PURPOSE:To eliminate the need for the process for cutting away partition walls and to make improvement in productivity by previously forming notches in the two corner parts at least at one end of an aluminum sheet material. CONSTITUTION:The notches 21a, 21a are previously formed in the two corner parts at least at one end of the aluminum sheet material 21. Such sheet material 21 is then passed through a working device arranged with plural rollers, by which both joint parts 23, 25 are bent approximately square to the same direction and thereafter, both side faces 22, 24 are bent approximately square to the inner side. Both side parts 22, 25 come into surface contact back to back with each other as the sections are molded flat and both joint parts 23,25 are so formed as to come into contact with a lower flat pat 26 of a tube 2. Since the notches 21a, 21a are formed on the other end side of the aluminum sheet material, the side end faces of the sheet material 21 are butted against each other and a U-turn part 12 for a heat medium is formed in this part.

Description

DETAILED DESCRIPTION OF THE INVENTION (Field of Industrial Application) The present invention relates to a heat exchanger having a tank at only one end of a large number of laminated tubes, and a method for manufacturing each of the tubes used therein.

(Prior Art) Conventionally, so-called single-tank type heat exchangers, in which a tank is provided only at one end of tubes stacked in parallel with each other with wavy fins interposed therebetween, are known, for example. 13
The one described in Japanese Patent No. 1268 is known.

In this type of heat exchanger, the inside of the tube is arranged in a longitudinal direction, and a partition wall divides the heat medium such as refrigerant and hot water into an outgoing path and a returning path, and one end of the tube is provided with an inlet for the outgoing path and an outlet for the return path. The inlet communicates with the inlet tank part of the tank part, and the outlet communicates with the outlet tank part of the tank part. Further, the partition wall is cut off at the other end of the tube, and a U-turn portion for the heat medium is provided in which the outgoing path and the incoming path communicate with each other, and the other end of each tube is closed by an end plate. Then, the heat medium passes through the outgoing path in each tube from the inlet tank section, makes a U-turn at the U-turn section, and is passed from the incoming path to the outgoing tank section.

To manufacture this type of heat exchanger, tubes with partition walls are formed by extrusion molding, the partition wall on the other end of each tube is cut out, and then the tubes and fins are stacked alternately, and one end of the tube is After assembling the tank part on one side and the end plate on the other end of the tube, it is manufactured by integral brazing.

In addition, as a tube, ■JP-A-63-242432
As described in the publication, after cladding the surface of a rectangular long aluminum plate with brazing material, the aluminum plate is bent in the same direction by rolling the plate in the long plane direction, and both ends of the plate are It is known that after the contact portions are brought into contact with each other, the contact portions are made to protrude further inward to form partition walls for the forward and return paths. In this tube, after molding, the tube is passed through a solder bath to bond the inwardly protruding partition wall, and then the partition wall at the other end of the tube is cut off to provide a U-turn portion for the heat medium.

(Problem B to be solved by the invention) However, according to the heat exchanger described in the above-mentioned publication, the partition wall is formed over the entire length of the tube when manufacturing the tube, so it is difficult to provide a U-turn portion. A process of cutting off a predetermined length of the partition wall on the other end of the tube is required, and if such a cutting process is provided, there is a problem that mass production becomes poor and costs increase.

In addition, when assembling a heat exchanger and brazing it together in a furnace, the brazing material on the tube surface tends to flow downward, making it difficult to securely connect the wavy fins and tubes, and There was a risk that the brazing material would become defective. Particularly, in the heat exchanger as described in (1) above, the tubes of the brazing material are deformed in the width direction due to thermal expansion over time, and the properties of the brazing material are accordingly deteriorated.

Therefore, an object of the present invention is to provide a method for manufacturing a tube that can eliminate the step of cutting out the partition wall, and a method for manufacturing a heat exchanger using this tube, which can further improve the properties of the brazing material. .

(Means for Solving the Problems and Their Effects) The method for manufacturing a heat exchanger tube according to the first invention includes cladding the surface of a long rectangular aluminum plate with a brazing material, and then bending and forming the aluminum plate. A method for manufacturing a heat exchanger tube including a tube provided in a hollow shape by an outer wall and a partition wall partitioning the inside of the tube is improved, and the method includes pre-notching two corners at at least one end of the aluminum plate material. The notch depth in the direction in which both of the notch parts face each other is such that a cutout part is formed only for the partition wall after the bending and forming. be.

Therefore, ゛C, Prayer folded form, especially ヂ: L-P ☆II
A U-turn portion of the heat medium is formed on the 6 side, and the conventional partition wall cutting process is not required.

A method for manufacturing a heat exchanger according to a second aspect of the present invention includes bending and forming a long rectangular aluminum plate material whose surface is clad with brazing material to form a hollow tube formed by an outer wall, and an inner part of the tube. Notches are formed in advance at two corners of at least one end of the aluminum plate of the heat exchanger tube provided with a partition wall that partitions the tube, and the depth of the notch in the direction in which the two notches are opposite is formed in advance. A heat exchanger tube is formed with a depth such that a cutout is formed only at the partition wall after the bending, and a brazing material having a melting point higher than that of the brazing material of the aluminum plate material is added to the tube. After wrapping the band-shaped thin material formed by the above, the tubes and fins are alternately laminated, and these are joined by brazing.

Therefore, there is no need to remove the partition wall, and since each tube is bound from the surrounding area by a band-like thin material, deformation of the duplex is sometimes suppressed during brazing, and after the brazing material of the plate material has melted and rotated, , the band-like thin material melts, and this band-like thin material secures the connection between the fin and the tube.

(Example) An embodiment of the present invention will be described below based on the drawings.

FIG. 1 is a front view showing a single tank type heat exchanger according to this embodiment.

This heat exchanger 1 has a large number of flat tubes 2 stacked in parallel with each other via wavy fins 3, one end side of these flat tubes 2 is connected to a tank part 4, and the flat tubes 2
The other end side is connected to end plays 1 and 5. still,
In the figure, numerals 6 and 7 indicate side plates, and the thin members of each part are made of aluminum material.

As shown in FIGS. 2 and 3, each flat tube 2 is
A partition wall 9 is provided from one end to the vicinity of the other end, and the partition wall 9 divides the inside of the tube 2 into an outgoing path 11 and an incoming path 13 for the heat medium along the longitudinal direction. On the other hand, there is a second
As shown in the figure and FIG. 4, a U-turn 12 is formed in which the refrigerant makes a U-turn and flows from the outgoing path 11 to the incoming path 13. Such a flat tube 2 is formed by sequentially bending a plate material of a predetermined shape using a plurality of rollers.

The opening on the other end side of each tube 2 is closed by a side plate 5 joined thereto. An inlet 10 for an outgoing route 11 and an outlet 14 for an incoming route 13 are provided at one end of the tube 2, and one end of the tube 2 is inserted into and joined to a tube insertion hole 4a provided in a tank portion 4.

The tank section 4 is partitioned into an inlet tank section 17 and an outlet tank section 18 by a partition wall 16 provided so that the inside comes into contact with the end surface of the partition wall 9 of each tube 2. A refrigerant inlet 10 and an outlet tank portion 18 are communicated with each heat medium outlet 14, respectively. Further, the inlet tank section 17 is provided with an inlet joint 19, and the outlet tank section 18 is provided with an outlet joint 20, respectively.

Next, the case of manufacturing the flat tube 2 and the heat exchanger 1 will be explained.

First, in order to manufacture each flat tube 2, an aluminum plate material 21 is manufactured as shown in FIG. Said plate material 21
is a rectangular long material whose surface is clad with brazing material.
On both sides along the longitudinal direction, that is, on the upper and lower sides in FIG. Joints 23, 25 are respectively provided. These sides 2
2 and 24 and the joint portions 23 and 25 are formed from one end of the plate 21 to the vicinity of the other end, and are not provided at the other end of the plate 21. That is, it is formed in a shape with a notch on the other end of the rectangle.

To explain this in detail, notches 21 are preliminarily formed in two corners of at least one end of the aluminum plate material 21.
a, 21a are formed in advance, and the notch depth d in the direction in which both the notches face each other is set so that the cutout portion (U-turn portion 1
2) is the depth at which it is formed. Here, "the depth at which the cutout part (U-turn part 12) is formed only for the partition wall 9" means that the part of the joint part 23.25 is insufficient,
It must not reach the outer wall of the tube 2 (if it reaches the outer wall of the tube 2, heat medium leakage will occur).

), thus pointing to the part corresponding to the side part 22.24.

Next, the tube 2 is formed by passing such a plate material 21 through a processing device in which a plurality of rollers are arranged. That is, both joint portions 23, 25 are bent substantially at right angles in the same direction, and then both side portions 22, 24 are bent inward at substantially right angles. Then, as the cross section is formed into a flat shape, the both side parts 22.25 face each other back to back, and both joint parts 23.25 come into contact with the lower flat part 26 of the tube 2, as shown in FIG. It is molded as follows. Further, on the other end side of the aluminum plate material, notches 21a, 2
Since plate 1a is formed, as shown in FIG.
The side end surfaces of the heat transfer medium 1 abut against each other, and a U-turn portion 12 of the heat medium is formed at this location. therefore,
In such a flat tube 2, a recess 27 is formed in the central portion of the upper flat plate portion in the longitudinal direction due to bending of both side portions 22 and 24. At this point, the joint part is 23°25
The side end surfaces of the U-turn portion 12 are not brazed to each other, and the U-turn portion 12 is kept in a flat bottom shape.

Furthermore, as shown in FIG. 7, each flat tube 2 is encircled by a plurality of band-like members 30, and the wavy fins 3 are stacked alternately. The band-like member 30 is formed of a plating sheet (brazing material) having a higher melting point than the brazing material cladding the plate material 21 . Moreover, the band-like member 30
is ringed so as to be positioned between the wavy fins when laminated, and binds the flat tube 2 from the periphery at multiple points in the longitudinal direction, such as between the bent side portions 22 and 24 or at the joint portion 2.
3.24 and the flat portion 26 are assembled to ensure abutment at the time and to suppress deformation in the width direction.

Next, flat tubes 2 alternately stacked with wavy fins 3
While inserting one end side into the insertion hole 4a of the tank part 4,
The end plate 5 is brought into contact with the other end of the flat tube 2, and is integrally assembled using a jig, after which integral brazing is performed in a furnace in this state.

Then, in the furnace, the temperature gradually rises and when it reaches the melting point of the brazing material clad on the surface of the flat tube 2,
This brazing material melts and spreads around the joints of each part. For example, between tube sides 22.24, junction 23.
24 and the flat portion 26, 1, the wavy fin 3 and the tube 2, one end of the tube and the tank portion 4, the other end of the tube and the end plate 5, etc. are surrounded by solder metal, and are joined by these solder metals. When the temperature inside the furnace further increases, the band member 30 made of a plating sheet wrapped around each flat tube 2 starts to melt.

This brazing material 30 flows to the lower surface of the tube flat part 26,
It is supplied to the joint between the wavy fin 3 and the tube flat part 26 to ensure their joint. It is also supplied to the concave portion 27 of the upper flat portion of each flat tube 2, so that the flat tubes 2 themselves can be reliably joined, and external leakage of the heat medium from the flat tubes 2 can be reliably prevented. In this way, the single tank type heat exchanger 1 shown in FIG. 1 is obtained.

Note that the method for manufacturing a heat exchanger using the band-like member 30 described above is not limited to that of the above embodiment, but can also be applied to a conventional tube.

(Effects of the Invention) As explained above, according to the first invention, by simply forming a notch at the end of the aluminum plate in advance, parts other than the notch during tube manufacturing can be Since the tube partition wall is formed up to the vicinity of the other end, and a U-turn portion is formed at the other end of the tube, the conventional process of cutting out the partition wall is no longer necessary, and mass production is improved. You can improve your performance.

In addition, since integral brazing materials sometimes bind each tube with a band-like member with a high melting point, deformation of the tubes can be prevented and reliable brazing is possible.
Since the band-like member itself is a brazing material, this brazing material ensures the bonding between the fins and the tube, and also ensures the bonding of the tube partition wall, thereby reliably preventing external leakage of the heat medium in the tube. becomes possible.

[Brief explanation of drawings]

1 to 7 show an embodiment according to the present invention, FIG. 1 is a front view of a heat exchanger, and FIG. 2 is an II--
3 is a sectional view taken along the line mm in FIG. 2, FIG. 4 is a sectional view taken along the line IV-IV in FIG. 2, and FIG. 5 is a plan view of the plate. FIG. 6 is a perspective view of the tube, and FIG. 7 is a perspective view showing how the tube and fin are assembled. 1... Heat exchanger 3... Fin 9... Partition wall 12... U-turn part 17... Inlet side tank 21... Plate material 22.24... Side part 2... Tube 4... Tank Iku 11... Outbound trip 13... Return trip 18... Outlet side tank portion 21a... Notch section 30... Band-like member

Claims (2)

[Claims] (1) After cladding the surface of a long rectangular aluminum plate material with brazing material, the aluminum plate material is bent and formed to form a hollow tube formed by an outer wall and a partition wall that partitions the inside of the tube. In the method for manufacturing a heat exchanger tube provided, notches are formed in advance at two corners of at least one end of the aluminum plate, and the notches are formed in opposite directions. A method for manufacturing a tube for a heat exchanger, characterized in that the notch depth is set to such a depth that a cutout is formed only on the partition wall after the bending. (2) A tube for a heat exchanger, which is formed by bending a long rectangular aluminum plate whose surface is clad with brazing material, and is provided with a hollow tube formed by an outer wall and a partition wall that partitions the inside of the tube. Notches are formed in advance at two corners of at least one end of the aluminum plate material, and the depth of the notches in the direction in which both the notches face each other is set to A heat exchanger tube is formed with a depth such that a cutout is formed only at the partition wall, and a band-shaped member made of a brazing material having a melting point higher than that of the brazing material of the aluminum plate material is wrapped around the tube. A method for manufacturing a heat exchanger, characterized in that the tubes are then laminated alternately with fins, and these are joined by brazing.