JP2002228378A - Heat exchanger - Google Patents

Abstract

PROBLEM TO BE SOLVED: To prevent a tube from being damaged owing to thermal stress while suppressing lowering of bending rigidity of a side plate. SOLUTION: The size T1 of the thickness of a junction 123 with a header tank 120 in a side plate 130 is assumed to be the size (h) of a tube 111 in the direction of a short diameter or less. Consequently, tensile strength of the side plate 130 can be partly reduced without severely deteriorating bending rigidity of the entire of the side plate 130. Accordingly, a difference between the amount of expansion of the side plate 130 and that of the tube 111 can be absorbed at the junction 123, so that the tube 111 can be prevented from being damaged owing to thermal stress while suppressing the lowering of the bending rigidity of the side plate 130.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

The present invention relates to a heat exchanger, and is effective when applied to a sensible heat exchanger such as a radiator or a heater for exchanging heat between cooling water of an engine (internal combustion engine) and air. .

[0002]

2. Description of the Related Art The general structure of a heat exchanger is described, for example, in Utility Model Registration No. 305.
As described in JP-A-9971, a plurality of flat tubes, a header tank joined to both ends in the longitudinal direction of the tube and communicating with the tube, and a length extending parallel to the tube so as to pass between the two header tanks. The directional end is formed of a reinforcing plate or the like joined to the header tank.

Here, the reinforcing plate is a reinforcing member for increasing the mechanical strength of a heat exchange portion (core portion) composed of a tube and a fin, and is usually made of a metal plate having a U-shaped cross section. I have.

In order to improve the heat exchange efficiency of the radiator while suppressing an increase in the size of the radiator (heat exchanger), the dimension of the flat tube in the short diameter direction (the thickness of the tube) is required.
It is effective to reduce the size of the heat exchange part (core part) (increase the heat transfer area) by reducing the distance between the tubes and increasing the number of tubes.

At this time, in order to suppress an increase in the mass of the radiator with an increase in the number of tubes, the wall thickness of the tube is reduced (reduced in thickness). ) Because the strength is reduced,
The tube is likely to be damaged by thermal stress generated due to the difference between the linear expansion coefficient (expansion amount) of the reinforcing plate and the linear expansion coefficient (expansion amount) of the tube.

To cope with this, as described in the above publication, a part of the reinforcing plate may be curved to absorb a difference in expansion and contraction due to a difference in linear expansion coefficient (expansion). In this case, since the reinforcing plate needs to be curved, the material cost of the reinforcing plate increases.

Further, if the strength of the entire reinforcing plate is reduced in accordance with the tube, the generation of thermal stress can be suppressed, but the bending rigidity of the reinforcing plate also decreases. There is a high possibility that it will not function sufficiently as a member.

In view of the above, it is an object of the present invention to prevent a tube from being damaged by thermal stress while suppressing an increase in material cost of a reinforcing plate and a decrease in bending rigidity of the reinforcing plate.

[0009]

According to the present invention, in order to achieve the above object, a plurality of tubes (111) formed in a flat shape and through which a fluid flows are provided.
And a plurality of tubes (111) joined at both ends in the longitudinal direction of the tube (111),
(1) Two header tanks (120) extending in a direction orthogonal to the longitudinal direction, and extend parallel to the longitudinal direction of the tube (111) so as to pass between the two header tanks (120). 120), and a reinforcing plate (130) joined to the reinforcing plate (130).
At least the joint (12) with the header tank (120)
The thickness dimension (T1) of 3) is not more than the minor dimension (h) of the tube (111).

Thus, the tensile strength of the reinforcing plate (130) can be partially reduced without greatly reducing the bending rigidity of the entire reinforcing plate (130).

Therefore, the difference between the amount of expansion of the reinforcing plate (130) and the amount of expansion of the tube (111) can be absorbed by the joint (123), so that the material cost of the reinforcing plate (130) increases. And reinforcement plate (13
It is possible to prevent the tube (111) from being damaged due to thermal stress, while suppressing the decrease in bending stiffness of (0).

According to the second aspect of the invention, corrugated fins (112) are provided between the plurality of tubes (111) and between the tubes (111) and the reinforcing plate (130). The reinforcing plate (130) is joined to the header tank (120) at the longitudinal end of the header tank (120).
3) is that the surface on the opposite side of the tube (111) is stepped so that the thickness (T1) of the tube (1) is reduced.
It is characterized in that it is configured to be smaller than the minor dimension (h) of 11).

Accordingly, the surface of the reinforcing plate (130) on the tube (111) side can be made a flat surface without irregularities (stepped) without reducing the thickness of the reinforcing plate (130). .

Therefore, the fin (112) can be brought into contact (joining) with the reinforcing plate (130) also at the joining portion (123), so that the thickness (T1) of the joining portion (123) can be reduced. It is possible to prevent the strength (rigidity) of the heat exchanger from being greatly reduced.

According to the third aspect of the present invention, the plurality of tubes (111) and the joints (123) are provided in the insertion holes (121a, 121b) formed in the header tank (120).
And is joined to the header tank (120) while being further inserted into the header tank (120). The dimensions between the plurality of tubes (111), and the tubes (111) and the reinforcing plate (130)
And the insertion hole (121a) into which the tube (111) is inserted and the insertion hole (121b) into which the joint (123) is inserted are equal in size. .

As a result, the workability of the header tank (120) is improved by successively improving the workability of the insertion hole, so that the production cost of the header tank (120) (heat exchanger) can be suppressed while suppressing the heat cost. The tube (111) can be prevented from being damaged by stress.

The present invention is applied to a heat exchanger in which the tube (111) is made of an aluminum alloy and has a wall thickness (t) of 0.25 mm or less. Then it is effective.

Incidentally, the reference numerals in parentheses of the above means are examples showing the correspondence with specific means described in the embodiments described later.

[0019]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS In the present embodiment, a heat exchanger according to the present invention is applied to a radiator for cooling a cooling water of an engine for running a vehicle, and FIG. 1 shows a radiator 100 according to the present embodiment. It is a perspective view of.

Reference numeral 111 denotes an aluminum tube through which cooling water (fluid) flows and which has a flat (elliptical) cross section. A corrugated (corrugated) tube is provided between the plurality of tubes 111. A fin 112 made of aluminum is formed, and the fin 112 and the tube 111 constitute a core portion 110 for performing heat exchange between cooling water and the atmosphere.

On one end side of the tube 111 in the longitudinal direction (left side in FIG. 1), it extends in a direction orthogonal to the longitudinal direction of the tube 111 and communicates with a plurality of tubes 111 to supply cooling water to each tube 111. Distribute and supply first
A header tank 120a is provided, and a plurality of tubes 111 are provided on the other end side, similarly to the first header tank 120a.
A second header tank 120b that collects and collects the cooling water flowing out of each tube 111 in communication with the second column 111 is provided.
The two header tanks 120a and 120b have the same structure.
20a and 120b are collectively called header tank 120.

Incidentally, reference numeral 120c denotes an inflow side joint portion connected to the cooling water outflow side of the engine.
Reference numeral denotes an outflow joint connected to the cooling water inflow side of the engine.

The header tank 120 has a square pipe-shaped tank main body 120e and a tank cap 120f for closing both ends in the longitudinal direction of the tank main body 120e. As shown in FIG. 3, the first and second tank plates (tank members) 121 and 122 made of aluminum are joined together.

As shown in FIG. 1, both ends of the core portion 110 extend parallel to the longitudinal direction of the tube 111 so as to pass between the two header tanks 120 and are joined to the header tank 120. Side plate (reinforcement plate)
The side plate 130 increases the mechanical strength of the core 110.

The tube 111 and the side plate 130 are connected to the header tank 12 as shown in FIGS.
0 (first tank plate 121), insertion hole 1
It is joined to the header tank 120 by brazing while being inserted into 21a, 121b (see FIG. 4B).

In the present embodiment, the fin 112 is brazed to the tube 111 and the side plate 130 by the brazing material coated (cladded) on the front and back surfaces of the fin 112.

The side plate 130 is formed in a U-shaped cross section by press-forming an aluminum plate material having a thickness To larger than the minor dimension h of the tube 111. At least the joint 123 between the plate 130 and the header tank 120 is a tube 111 as shown in FIG.
The surface on the opposite side is stepped so that the wall thickness T1 is equal to or smaller than the minor dimension h of the tube 111 (T1 = h in the present embodiment).

Further, the dimension P between the tubes 111
1 and the dimension P2 between the tube 111 and the side plate is made equal (P1 = P2), and FIG.
As shown in FIG.
1a and the insertion hole 121b into which the joint 123 is inserted have the same size (combination).

The dimension h in the minor axis direction of the tube 111 refers to the dimension measured by the outer wall in the minor axis direction of the tube 111 as shown in FIG. In the present embodiment, when the side plate 130 is press-formed, the joint 12
The joint portion 123 is formed in a stepped shape by pressing a portion corresponding to No. 3 with a pressing means such as a roller.

Next, the features (effects) of this embodiment will be described.

In this embodiment, at least the joint 123 between the side plate 130 and the header tank 120 is provided.
Is set to be smaller than or equal to the minor dimension h of the tube 111 (T1 = h in the present embodiment), so that the tensile strength of the side plate 130 can be reduced without greatly reducing the bending rigidity of the entire side plate 130. Can be partially reduced.

Therefore, the difference between the amount of expansion of the side plate 130 and the amount of expansion of the tube 111 can be absorbed by the joint 123, so that the material cost of the side plate 130 increases and the bending rigidity of the side plate 130 decreases. It is possible to prevent the tube 111 from being damaged due to thermal stress while suppressing the decrease.

Further, by forming the surface on the side opposite to the tube 111 to be stepped, the thickness T1 of the joint portion 123 is smaller than the minor dimension h of the tube 111 (T1 = h in the present embodiment). With such a configuration, the surface of the side plate 130 on the tube 111 side can be made a flat surface without irregularities (stepped) without reducing the thickness To of the side plate 130.

Therefore, the fin 112 can be brought into contact (joining) with the side plate 130 also at the joining portion 123, so that the strength (rigidity) of the core portion 110 increases even if the thickness T1 of the joining portion 123 is reduced. It can be prevented from lowering.

The dimension P1 between the tubes 111 and the dimension P2 between the tubes 111 and the side plates are made equal (P1 = P2), and the insertion holes 121a into which the tubes 111 are inserted and the joints 123 are inserted. Since the insertion hole 121b and the insertion hole 121b have the same size (congruent), successive workability of the insertion hole is improved, and the header tank 120
Workability is improved. Therefore, the header tank 120
It is possible to prevent the tube 111 from being damaged by thermal stress while suppressing an increase in the manufacturing cost of the (radiator 100).

The present embodiment is particularly effective when the thickness t (see FIG. 5) of the tube 111 is small (0.25 mm or less).
1 has a thickness t of 0.2 mm.

(Other Embodiments) In the above embodiment, the heat exchanger according to the present invention is applied to a radiator.
The present invention is not limited to this, and can be applied to other heat exchangers such as an indoor heat exchanger or an outdoor heat exchanger of an air conditioner.

In the above embodiment, the fin 112
Is a sinusoidal wave, but the present invention is not limited to this, and may be, for example, a rectangular wave or an offset fin.

Further, in the above-described embodiment, the joining portion 123 is formed in a stepped shape by pressing, but the present invention is not limited to this. For example, a stepped shape is formed by cutting such as milling. It may be.

[Brief description of the drawings]

FIG. 1 is a perspective view of a heat exchanger (radiator) according to an embodiment of the present invention.

FIG. 2 is a perspective view of a header tank according to the embodiment of the present invention.

FIG. 3 is a sectional view of a header tank according to the embodiment of the present invention.

FIG. 4A is an enlarged view of a joint of the heat exchanger according to the embodiment of the present invention, and FIG. 4B is a schematic view showing an insertion hole of a first tank plate.

FIG. 5 is a sectional view of a tube according to the embodiment of the present invention.

[Explanation of symbols]

100 radiator, 110 core part, 111 tube, 112 fin, 120 header tank, 130
Side plate (reinforcement plate).

Claims (4)

[Claims] 1. A plurality of tubes (111) formed in a flat shape and through which a fluid flows, and the plurality of tubes (111) positioned at both longitudinal ends of the tubes (111) are joined, Two header tanks (120) extending in a direction orthogonal to the longitudinal direction of the tube (111); and extending parallel to the longitudinal direction of the tube (111) so as to pass between the two header tanks (120). The reinforcing plate (13) joined to the header tank (120)
0), and at least the thickness (T1) of the joint (123) of the reinforcing plate (130) with the header tank (120) is the minor dimension (h) of the tube (111). ) A heat exchanger characterized by the following. 2. The method according to claim 1, wherein the plurality of tubes (111) and the tubes (111) and the reinforcing plate (13) are provided.
0), a fin (112) formed in a wavy shape is disposed, and the reinforcing plate (130) is connected to the header tank (1).
20) At the longitudinal end of the header tank (120)
Further, the joint (123) is connected to the tube (11).
The surface on the side opposite to 1) is stepped, so that the wall thickness (T1) is smaller than the minor dimension (h) of the tube (111). The heat exchanger according to claim 1. 3. The header tank (120) with the plurality of tubes (111) and the joint (123) inserted into insertion holes (121a, 121b) formed in the header tank (120). ), And a dimension between the plurality of tubes (111), and the tubes (111) and the reinforcing plate (13).
0) and the tubes (11)
1) and an insertion hole (121a) into which the joint (1) is inserted.
The heat exchanger according to claim 1 or 2, wherein the insertion hole (121b) into which the insertion member (23) is inserted is equal in size. 4. The tube (111) is made of an aluminum alloy and has a thickness (t) of 0.25 m.
The heat exchanger according to any one of claims 1 to 3, wherein m is equal to or less than m.