JPH1089885A - Connecting section between metallic tank and metallic inlet pipe for heat exchanger - Google Patents

Abstract

PROBLEM TO BE SOLVED: To improve a strength of a connecting section between an inlet pipe and a tank, and further improve an anti-corrosion characteristic of a seat plate and a heat transfer pipe. SOLUTION: A connecting bracket 22 having a cylindrical part 23, a flange part 25 and an end plate part 24 is brazed to a tank 2. The end part of an inlet pipe 13 is brazed to an inside part of the cylindrical part 23. A brazing area of each of the brazed sections is ensured to improve a connecting strength. Cooling water fed from an inlet pipe 13 into the tank 2 strikes against the upper end plate 24 and is dispersed around it. Accordingly, occurrence of strong striking of cooling water against a seat plate 6 or heat transferring plates 3, 3 can be eliminated and corrosion resistant property can be improved.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

TECHNICAL FIELD The present invention relates to a metal tank for a heat exchanger which constitutes a heat exchanger used as a heater core or the like incorporated in an air conditioner of an automobile or the like.
The present invention relates to a junction with a metal inlet pipe that supplies and discharges cooling water to the inside of the metal tank.

[0002]

2. Description of the Related Art As a conventionally known heat exchanger used as a heater core of an air conditioner for an automobile or the like, a structure as shown in FIG. 9 is described in, for example, JP-A-5-34090. ing. This heat exchanger 1 is formed by combining constituent members each made of an aluminum alloy and integrally joining them by brazing. That is, FIG.
As shown in the figure, a pair of aluminum alloy tanks 2 and 2 arranged in parallel with each other are provided, and between the tanks 2 and 2, a plurality of flat heat transfer tubes 3 and 3 and corrugated fins are provided. 4 and 4 are alternately arranged to form the core portion 5. Both ends (upper and lower ends in FIG. 9) of these heat transfer tubes 3 and 3 penetrate the pair of tanks 2 and 2 in a liquid-tight manner, respectively, and communicate their inner passages to the inside of the tanks 2 and 2. ing. These tanks 2, 2, heat transfer tubes 3, 3,
The inlet tube 13 and the outlet tube 16 described later are made of a so-called clad material in which a brazing material is laminated on at least one surface of a core material made of an aluminum alloy.

Each of the tanks 2 is formed by combining a seat plate 6 and a tank body 7 having a substantially boat shape in the middle. The end portions of the heat transfer tubes 3 are formed in the seat plate 6 with connection holes 8 having shapes and dimensions that can be inserted almost without any gap. Also, one of the tanks 2 (upper in FIG. 9) of the pair of tanks 2 and 2
Is provided with a partition plate 9 at an intermediate portion inside, and divides the inside of the tank 2 into an inlet chamber 10 and an outlet chamber 11. Then, on the upper surface of the tank body 7 of the tank 2,
Through holes 12 and 12 are formed at positions corresponding to 0 and the outlet chamber 11. The base ends 14, 14 of the inlet pipe 13 and the outlet pipe 16 are respectively joined to the through holes 12, 12.

[0004] In the heat exchanger 1 configured as described above, the abutting portions of the constituent members are brazed to each other to integrally join the constituent members together. That is, the tanks 2, 2, the heat transfer tubes 3, 3, the fins 4, 4, the partition plate 9, the inlet tube 13, and the outlet tube 16 are assembled as shown in FIG. Put in furnace.
Then, in this heating furnace, a temperature (for example, 60 ° C.) higher than the melting point of the brazing material and lower than the melting point of the base material (aluminum alloy serving as a core material of each constituent member and maintaining strength).
(About 0 ° C). By this heating, the fins 4 and 4 and the heat transfer tubes 3 and 3 made of the clad material, the seat plate 6,
6. The brazing material existing on the surfaces of the tank bodies 7, 7, the partition plate 9, the inlet pipe 13, and the outlet pipe 16 is melted, and the above-described constituent members are joined by brazing.

The operation when the heat exchanger 1 configured as described above is used as a heater core is as follows.
When heating the vehicle interior, cooling water heated in a water jacket of the engine is sent from the piping (not shown) to the inlet chamber 10 via the inlet pipe 13. This cooling water is provided at one end (FIG. 9) on the inlet chamber 10 side.
Are transferred to the other tank 2 side through the heat transfer tubes 3 and 3 passed through the upper ends of the heat transfer tubes 3 and 3 and further passed through the other ends (lower ends in FIG. 9) toward the outlet chamber 11 side. And reaches this exit chamber 11. And this exit room 11
From the outlet pipe 16 provided on the side, it returns to the water jacket of the engine through a pipe (not shown). By circulating the cooling water in this manner, the temperature of the core portion 5 rises. If air is flowed between the heat transfer tubes 3 and 3 and the fins 4 and 4 constituting the core portion 5, the air is It can heat and heat the room.

However, in the case of the conventional heat exchanger configured as described above, the cooling water sent from the inlet pipe 13 to the inlet chamber 10 is supplied to the seat plate provided immediately below the inlet pipe 13. 6 and directly hit the ends of the heat transfer tubes 3 and 3. As described above, the cooling water directly collides with the surface of the seat plate 6 and the ends of the heat transfer tubes 3, 3, so that the corrosion of the end portions of the seat plate 6 and the heat transfer tubes 3, 3 proceeds.

As a structure for solving such a problem,
Heat exchangers such as those described in U.S. Pat. No. 5,465,783 are known. 10 to 11 show the structure. In the first example shown in FIG. 10, a member corresponding to the above-described conventional inlet pipe 13 (see FIG. 9) is configured by internally fitting and fixing the inlet pipe 17 to the inlet cup 18a. An O-ring 19 is provided between the lower surface of the flange provided on the outer peripheral surface of the inlet pipe 17 and the inner peripheral surface of the inlet cup 18a to maintain watertightness between the inlet pipe 17 and the inlet cup 18a. I have. A sacrificial corrosion member 20 is disposed immediately below the inlet pipe 17 and between the lower end opening of the inlet pipe 17 and the surface of the seat plate 6. Further, the second example shown in FIG. 11 has a structure in which a bottomed cylindrical inlet cup 18b is extended from the lower end edge of the inlet pipe 17 to below. A plurality of through holes 28, 28 are provided in a part of the peripheral wall of the inlet cup 18b which does not overlap with the inlet pipe 17, in order to discharge cooling water to the surroundings. With these structures, the cooling water sent from the inlet pipe 17 collides with the upper surface of the sacrificial corrosion member 20 or the bottom surface of the inlet cup 18b, and is dispersed around the surface. The end of the heat transfer tubes 3 and 3 is prevented from colliding. Thereby, the corrosion resistance of the end portions of the seat plate 6 and the heat transfer tubes 3 is improved as compared with the conventional heat exchanger.

[0008]

However, the joint between the tank 2 and the inlet pipe 13 and the inlet cup 18a (18b) constituting the inlet pipe described in these U.S. Pat. ) Is simply inserted into the through hole 12 formed in the tank 2 and the abutting portion is brazed. That is, in the first and second examples, the inlet cup 1
The junction between the tank 8 and the tank 2 is in contact with a part of the outer peripheral surface of the peripheral wall of the inlet cup 18a (18b) and the inner peripheral edge of the through hole 12 provided in the tank body 7 constituting the tank 2. Department only. The inlet cup 18a (18b)
The opening flange 29a (29b) provided in the opening serves as a stopper when the inlet cup 18a (18b) is inserted. Accordingly, the contact area between the opening flange 29a (29b) and the tank body 7 is also limited. The inlet cup 18a (18b) is connected to the through hole 12a.
Is brazed integrally with the other constituent members described above. Thereafter, the inlet pipe 17 is connected to the inlet cup 18a such that the O-ring 19 is sandwiched between the lower surface of the flange provided on the outer circumferential surface of the inlet pipe 17 and the inner circumferential surface of the inlet cup 18a (18b). Insert it all the way inside (18b). Thereby, the O-ring 19
Are the lower surface of the flange portion and the inlet cup 18a (18)
b) is elastically compressed between the inner pipe and the inlet pipe 1
7 and the inlet cup 18a are kept watertight. The outer peripheral surface of the inlet pipe 17 and the inlet cup 18a (18)
Since the inner peripheral surface of b) includes the O-ring 19 inside,
Brazing in the furnace is not possible. Therefore, the inlet pipe 17 is connected to the inlet cup 18a (18
b) cannot be fixed by brazing.
In this manner, the brazing of the inlet pipe 17 and the inlet cup 18a (18b) constituting the inlet pipe is performed only at one location due to the thickness of the inner peripheral edge of the through hole 12, and the inlet pipe is connected to the tank body 7 by the brazing. The bonding strength is not always sufficient. In the case of the heat exchanger 1 shown in FIG. 9, the tank body 7 and the inlet pipe 13 and the outlet pipe 16 are fixed only by brazing, but these two pipes 13 and 16 and the tank body 7 are fixed.
Contact area is small. Therefore, it is difficult to secure sufficient bonding strength.

The joint between the metal tank for a heat exchanger and the metal inlet pipe of the present invention improves the corrosion resistance of the metal tank, the metal inlet pipe, and the heat exchanger in view of the above-described circumstances. By brazing integrally with the joining bracket to be used to increase the brazing joint area, the joining strength of the metal inlet pipe to the metal tank and the corrosion resistance of the heat exchanger are sufficiently improved. It was invented.

[0010]

The joint between the metal tank for a heat exchanger and the metal inlet pipe of the present invention is formed by a first through hole formed on a wall plate of the metal tank constituting the heat exchanger. Holes and
A joining bracket fixed to the inside of the first through-hole by brazing and a metal inlet pipe joined to the wall plate of the tank via the joining bracket are provided. The joining bracket includes a tubular portion that can be inserted inside the first through hole, an end plate portion that closes an opening of a portion existing inside the metal tank at one end of the tubular portion, An outward flange-shaped flange portion formed at a portion existing outside the metal tank at the other end of the portion, at least one protruding piece projecting from an inner peripheral surface of the cylindrical portion, and A second through-hole formed in a portion of the protruding piece closer to the end plate than the edge of the protruding piece on the flange side. In addition, the joining bracket is configured such that one surface of the flange portion is abutted against the peripheral portion of the first through hole on the outer surface of the wall plate portion of the metal tank, and the one surface and the outer surface are formed over the entire circumference. I'm brazing all over. Then, the end of the metal inlet tube is inserted into the cylindrical portion without play until the leading edge of the metal inlet tube abuts against the protruding piece, and the inner peripheral surface of the cylindrical portion is The inside of the joining bracket is fixed to the inside of the joining bracket by brazing the entire outer periphery of the end of the metal inlet tube with the outer peripheral surface.

[0011]

The metal tank and the metal inlet pipe are connected to each other by the joint between the metal tank for the heat exchanger and the metal inlet pipe as described above. It is brazed and joined together via the closing bracket. Also, the joining area for brazing them is
The size can be greatly increased by using the joining bracket. In this way, the metal tank, the metal inlet pipe, and the joining bracket can be integrally joined by brazing, and the brazing joint area can be greatly increased.
The joining strength of the metal inlet pipe to the metal tank can be greatly improved. Further, the cooling water spouted from the metal inlet pipe into the metal tank directly collides with the surface of the seat plate constituting the heat exchanger and the end of the heat transfer pipe by the end plate portion of the joining bracket. Things disappear. As a result, the corrosion resistance of the heat exchanger can be significantly improved.

[0012]

1 to 4 show a first embodiment of the present invention. It should be noted that the same parts as those of the above-described conventional structure are not shown or described in duplicate, and will be omitted or simplified, and the following description will focus on features of the present invention. The tank 2 constituting the heat exchanger is formed by combining a seat plate 6 and a tank body 7 in the middle. These two members 6, 7
Is formed by a clad material in which a brazing material is laminated on at least one surface of a core material made of an aluminum alloy. At the bottom of the seat plate 6, connection holes 8 for inserting the ends of the heat transfer tubes 3 are formed. On the other hand, in the upper wall portion of the tank body 7 which is the wall plate portion of the tank 2, a first through hole 21 for inserting a joining bracket 22 described below is provided at a position corresponding to the entrance chamber 10 side. Has formed. The first through hole 21 may be formed by punching such as piercing, or may be formed by bending such as burring. If the first through hole 21 is formed by a bending process such as a burring process, a bent portion is formed on the inner peripheral edge thereof by squeezing. In any case, the joining bracket 22 can be inserted into the first through hole 21 without any gap. This joining bracket 22 is made of aluminum alloy.
It is made into a shape as shown in FIGS. The joining bracket 22 includes a cylindrical portion 2 that can be inserted inside the first through hole 21.
3 and an end plate portion 24 for closing an opening of a portion existing inside the tank 2 at one end portion (lower end portion in FIG. 3) of the cylindrical portion 23.
And an outward flange-shaped flange 25 existing outside the tank 2 at the other end (upper end in FIG. 3) of the cylindrical portion 23, and a protruding piece projecting from an inner peripheral surface of the cylindrical portion 23. 26, 26, and second through holes 27, 27 formed in a part of the cylindrical portion 23 closer to the end plate portion 24 than the projecting pieces 26, 26. The inlet tube 13 is freely inserted into the inside of the cylindrical portion 23 without any gap. When the distal end of the inlet pipe 13 is inserted into the inside of the cylindrical portion 23, the inlet pipe 1
The front end of the tank 2 contacts the opening side surface (the upper surface of FIGS.
Is positioned.

The joining bracket 22 is manufactured by subjecting an aluminum alloy plate to plastic working such as drawing. In addition, the projecting piece 26,
The operation for forming the second through holes 27 and the second through holes 27 is performed as follows. First, U-shaped cuts, each of which opens upward, are formed at a plurality of positions in the circumferential direction at a part of the cylindrical portion 23, and the inner portions of the cuts are respectively formed in the upper cylindrical portion 2.
By bending inward in the diametrical direction of No. 3, the bent portions are formed into protruding pieces 26, 26, and the holes formed in the inside of the cuts by bending are formed as second through holes 27, 27. still,
Actually, the cut forming operation and the bending operation are performed in one behavior.

When the tank 2 and the inlet pipe 13 are joined via the joining bracket 22 as described above, first, from the state of FIG. 2 to the state of FIG. The cylindrical portion 23 of the joining bracket 22 is inserted into the inside of the first through hole 21 provided, and one surface of the flange portion 25 (the lower surface in FIGS. 1 and 2) is connected to the outer surface of the tank body 7 (the upper surface in FIGS. ). Then, the distal end portion of the inlet pipe 13 is inserted into the cylindrical portion 23 without looseness until it comes into contact with the protruding pieces 26, 26 protruding from the inner peripheral surface of the cylindrical portion 23. In this manner, the distal end of the inlet pipe 13 is
The inlet pipe 13 is combined with the tank main body in a predetermined positional relationship in a state of being inserted into the inside. The joining bracket 22, the tank 2, and the inlet pipe 13 combined in this way are simultaneously brazed to other parts such as the core part 5, and the like.
The contact portions are brazed and integrated. As described above, the joining bracket 22, the tank 2, and the inlet pipe 1 are used.
The brazing material necessary for brazing at the time of brazing to 3 is supplied by a brazing material layer of a clad material constituting at least one of the members abutting on each other.

The tank 2 and the inlet pipe 1 assembled as described above
By joining the joint portion 3 with the joining bracket 22, the brazing joint area can be greatly increased. That is, the brazed joint between the joining bracket 22 and the inlet tube 13 is a contact portion between the inner peripheral surface of the cylindrical portion 23 of the joining bracket 22 and the outer peripheral surface of the end of the inlet tube 13.
Further, the brazing joint between the joining bracket 22 and the tank 2 is formed on one side of the flange 25 of the joining bracket 22 (FIG. 1).
2 and the outer surface of the tank body 7 (the upper surface in FIGS. 1 and 2), which is the wall plate portion of the tank 2, and the outer peripheral surface of the cylindrical portion 23 of the joining bracket and the through hole provided in the tank 2. A contact portion of the hole 21 with the inner peripheral surface. Since the area of each of these contact portions is sufficiently large, the brazing joint area of the joint between the tank 2 and the inlet pipe 13 can be greatly increased as compared with the conventional structure. As a result, the joining strength of the inlet pipe 13 to the tank 2 can be greatly improved. If the first through hole 21 is formed by bending such as burring, a short cylindrical bent portion is formed on the inner peripheral edge of the first through hole 21 as described above. The inner peripheral surface and the outer peripheral surface of the cylindrical portion 23 of the joining bracket 22 abut. Thereby, the inlet pipe 13 and the tank body 7
The bonding area of the brazing is further increased, and the holding strength of the inlet tube 13 is further improved.

Further, when the joint between the metal tank for a heat exchanger and the metal inlet pipe of the present invention is incorporated in a heat exchanger and this heat exchanger is used as a heater core, a joining bracket having an end plate portion 24 is used. Due to the presence of 22, heat resistance of the heat exchanger can be greatly improved. That is, the cooling water sent from the inlet pipe 13 into the tank 2 of the heat exchanger in which the joining bracket 22 is incorporated is supplied to the opening side face of the end plate 24 of the joining bracket 22 (upper side in FIGS. ), And is discharged from the second through holes 27, 27 to the outside in the diameter direction of the joining bracket 22. As a result, the cooling water does not directly collide with the surface of the seat plate 6 constituting the heat exchanger and the end portions of the heat transfer tubes 3, 3.
The corrosion resistance of the heat exchanger can be improved by preventing corrosion of the end of the heat exchanger.

Next, FIGS. 5 and 6 show a second example of the embodiment of the present invention. In the case of the present example, the bending direction of the protruding pieces 26a provided on the joining bracket 22a is different from that of the first example. That is, the joining bracket 2
In a part of the cylindrical portion 23 of 2a, at a plurality of locations in the circumferential direction,
A U-shaped notch opening in the circumferential direction side (left side in FIG. 5) is formed, and the inside of the notch is bent inward in the diametrical direction of the cylindrical portion 23, so that the bent portion is formed as the projecting piece 2.
6a and 26a. Then, the hole formed inside the cut is formed by bending the second through hole 27.
a and 27a. Other configurations and operations are the same as those in the first example.

Next, FIGS. 7 and 8 show a third embodiment of the present invention. In the case of this example, the cut portion 30 is formed at the tip end of the inlet pipe 13a. And this inlet pipe 1
A projecting piece 26b that engages with the cutout portion 30 is provided on a joining bracket 22b in which the inside 3a is fitted. The protruding piece 26b forms a U-shaped notch that opens in the circumferential direction side (left side in FIG. 7) at a part of the cylindrical portion 23 of the joining bracket 22b, and the inside portion of the notch is formed as described above. It is formed by bending the cylindrical portion 23 inward in the diameter direction. Then, the hole formed inside the cut by bending,
The second through hole 27b is provided. Note that the axial length d of the cut portion is sufficiently smaller than the axial length D of the protruding piece 26b (d≪D). That is, the notch portion 30 connects the inlet pipe 30 to the joining bracket 22b.
When the cooling water is inserted into the inside of the cylinder, it engages with the protruding piece 26b, and further, the cooling water discharged from the opening of the inlet pipe 13a is discharged from the second through hole 27b outward in the diameter direction of the cylindrical portion 23. I am doing it. This eliminates the need to fix the position of the inlet pipe in the rotational direction when brazing the heat exchanger with a jig or the like as in the related art, thereby facilitating assembly of the heat exchanger. Other configurations and operations are the same as those in the first and second examples.

[0019]

As described above, the joint between the metal tank for a heat exchanger and the metal inlet pipe according to the present invention is constructed and operates as described above. The corrosion resistance of the exchanger can be greatly improved.
Also, with the increase in the joining strength of the metal inlet pipe,
The strength of the metal inlet tube itself also increases. Further, with the increase in the joining strength and the strength of the metal inlet pipe itself, the metal tank itself can be made thinner and lighter. Further, as the corrosion resistance of the seat plate and the end of the heat transfer tube constituting the heat exchanger is improved, the heat transfer tube can be made flat and thin. Thereby, the heat transfer coefficient of the heat exchanger, that is, the performance of the heat exchanger and the brazing property between the heat transfer tubes and the fins can be improved.

[Brief description of the drawings]

FIG. 1 is a sectional view showing a first example of an embodiment of the present invention.

FIG. 2 is an exploded sectional view showing a state before joining of members to be incorporated in the structure of FIG. 1;

FIG. 3 is a perspective view of a joining bracket incorporated in the structure of FIG. 1;

FIG. 4 is a plan view of the same.

FIG. 5 is a perspective view of a joining bracket incorporated in a second example of the embodiment of the present invention.

FIG. 6 is a plan view of the same.

FIG. 7 is an exploded perspective view showing a state before joining of a metal inlet pipe and a joining bracket to be incorporated in the structure of the third example of the embodiment of the present invention.

FIG. 8 is a plan view of the joining bracket shown in FIG. 7;

FIG. 9 is a schematic sectional view showing a first example of a conventional heat exchanger.

FIG. 10 is a view showing the second example and corresponding to a portion A in FIG. 9;

FIG. 11 is a view similar to FIG. 10, showing the third example;

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 Heat exchanger 2 Metal tank 3 Heat transfer tube 4 Fin 5 Core part 6 Seat plate 7 Tank main body 8 Connection hole 9 Partition plate 10 Inlet chamber 11 Outlet chamber 12 Through holes 13, 13a Inlet pipe 14 Base end 16 Outlet pipe 17 Inlet pipes 18a, 18b Inlet cup 19 O-ring 20 Sacrificial corrosion member 21 First through hole 22, 22a Joining bracket 23 Tubular part 24 End plate part 25 Flange part 26, 26a, 26b Projection piece 27, 27a, 27b Second Through hole 28 Through hole 29a, 29b Opening flange 30 Notch

Claims (1)

[Claims] 1. A first through-hole formed in a wall plate portion of a metal tank constituting a heat exchanger, a joining bracket brazed and fixed inside the first through-hole, and the joining A metal inlet pipe joined to the wall plate portion of the tank via a bracket for use, the joining bracket includes a tubular portion that can be inserted inside the first through hole, and one end of the tubular portion. An end plate portion closing an opening of a portion existing inside the metal tank at the portion, and an outward flange-shaped flange formed at a portion existing outside the metal tank at the other end of the cylindrical portion. At least one protrusion protruding from the inner peripheral surface of the cylindrical portion, and a portion of the cylindrical portion formed closer to the end plate portion than the flange-side edge of the protrusion. A second through hole, wherein the joining bracket has a wall surface of the metal tank on one side of the flange. One side and the outer surface are brazed over the entire circumference in a state where the outer surface of the metal abuts against the peripheral portion of the first through hole, and the end of the metal inlet pipe is made of the metal. In a state in which the distal end edge of the inlet tube is inserted into the cylindrical portion without play until it abuts against the protruding piece, the inner peripheral surface of the cylindrical portion and the outer peripheral surface of the end portion of the metal inlet tube are formed all around. By brazing over
A joint between the metal tank for the heat exchanger and the metal inlet pipe, which is fixed inside the joining bracket.