JPH09229584A - Tube unit for heat exchanger and heat exchanger using the same - Google Patents

Abstract

PROBLEM TO BE SOLVED: To prevent a tube unit from bending while restricting an increasing of resistance at the flow passage by a method wherein ends of a pair of plates in their longitudinal direction are provided with projections projecting into the tube unit with a certain clearance being left between it and an opposing plate. SOLUTION: A tube unit 1 is comprised of a pair of trough-shaped plates 2 and a pair of plates 2 are connected to each other while being oppositely faced from each other to constitute a fluid passage 3 therebetween. The plate 2 is comprised of a flat bottom plate part 21, side plates 22 integrally and vertically installed at both side edges in parallel with a longitudinal direction of the bottom plate 21, and a flange 23 connected to one end of the side plate 22 and extending in parallel with the bottom plate 21. A projection 24 projecting toward an inward direction, the projection 24 is slightly projected at the fluid passage 3 to cause the plates 2 to be abutted from each other, resulting in that a clearance is assured between the opposed plates 2.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a tube unit used in a heat exchanger for automobiles and the like and a heat exchanger using the same, and more particularly to a heat exchanger having a fluid passage formed by joining a pair of plates to each other. The present invention relates to a tube unit and a laminated heat exchanger configured by arranging a plurality of the tube units in parallel.

[0002]

2. Description of the Related Art As a heat exchanger used for a heat exchanger for an automobile, for example, an evaporator, a condenser, an oil cooler, etc., a pair of gutter-shaped plates are opposed to each other so as to form a fluid passage therebetween and are joined to each other. There is known a plate type laminated heat exchanger in which a plurality of tube units are arranged in parallel to form a tube unit. In this type of heat exchanger, the longitudinal end of each tube unit is inserted into a slot formed in the header, and the tube unit is joined to the header by brazing or the like. A fluid (for example, a refrigerant) that has flowed into the tube unit from the header exchanges heat with the outside and then flows into another header. Therefore, the tube unit and the header (slot portion of the header) must be liquid-tightly joined so that a gap or the like does not occur.

In order to improve this joining property, the actual fairness 5-3
In the 1429 publication, as shown in FIGS. 9 and 10,
The pair of gutter-shaped plates 102 forming the tube unit 101 are provided with inward bulging portions 103, and the bulging portions 103 facing each other are abutted against each other to prevent the plate 102 from bending inward. Such a structure is disclosed. The prevention of the inward bending enables liquid-tight joining between the end of the tube unit 101 and the inner peripheral surface of the slot 105 of the header 104 (header plate).

[0004]

However, as shown in FIG.
In the structure shown in FIG. 10, since the bulging portions 103 are abutted against each other, the fluid passage 106 formed between the pair of plates 102 has a narrowed flow passage cross-sectional area at this portion and is partially blocked. However, there is a problem that the flow path resistance of the heat exchanger as a whole increases.

Further, since the bulging portions 103 abut each other, the inward bending of the pair of plates 102 is almost completely prevented, but the degree of freedom of each plate 102 is substantially completely lost. As a result, when the tube unit 101 is constructed by joining the pair of plates 102 to each other,
If the dimension is larger than the dimension of the slot 105, the tube unit 101 cannot be inserted or is extremely difficult to insert. On the other hand, if the size is smaller than that of the slot 105, it becomes difficult to liquid-tightly bond the both.

An object of the present invention is to pay attention to the above problems and to suppress an increase in the flow path resistance of the tube unit,
Prevents the bending of the end of the tube unit and at the same time gives the minimum degree of freedom for deformation, low flow resistance of the heat exchanger as a whole, liquid tight joint between the end of the tube unit and the slot of the header, The purpose is to ensure the ease of inserting the end of the tube unit into the slot of the header.

[0007]

In order to solve the above-mentioned problems, a tube unit for a heat exchanger according to the present invention has a pair of gutter-shaped plates facing each other so as to form a fluid passage therebetween. In a tube unit for a heat exchanger, which is joined to each other and whose longitudinal end is inserted into a slot formed in a header, in the tube unit having a gap between the longitudinal ends of the pair of plates and the opposing plates. It is characterized in that it is provided with a projecting portion projecting in one direction. That is, the protrusions that protrude inward of the tube unit are not abutted against the opposing plates.

The heat exchanger according to the present invention comprises such a tube unit and a header having a slot into which the longitudinal end of the tube unit is inserted.

In the tube unit as described above, the end portions of the plates are reinforced by forming the inwardly projecting portions at the longitudinal end portions of the pair of plates. This reinforcement is achieved by the effect of work hardening caused by deforming the metal plate, in addition to the geometrical effect (that is, the rib effect) of forming the protruding portion, and is particularly effectively reinforced by the latter. Particularly, when the tube unit is made of aluminum or aluminum alloy, effective reinforcement by work hardening is performed. Therefore, even if the protrusions are not in contact with each other, they have sufficient resistance to deformation, so that they are prevented from bending and liquid-tightly joined to the slots of the header.

Further, since a gap is secured between the projecting portion and the counter plate, the flow passage may be slightly narrowed at this portion, but it is not partially blocked and the flow passage resistance is reduced. A significant increase is prevented. Therefore, the flow path resistance of the heat exchanger as a whole can be suppressed to be small.

Further, since the protruding portion is not abutted against the opposing plate, it has sufficient rigidity (deformation resistance) as described above.
It is possible to have a degree of freedom for some deformation, that is, a minimum required degree of freedom while having the above. Therefore, when the tube unit is constructed, some flexibility in size is exerted, and even if some dimension error occurs with the slot of the header, the end portion of the tube unit is easily inserted into the slot.

[0012]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS Preferred embodiments of the present invention will be described below with reference to the drawings. 1 to 3 show a tube unit according to a first embodiment of the present invention and a relationship between the tube unit and a header plate of a header. FIG. 1 shows a state before the tube unit is inserted into the slot of the header plate, and FIGS. 2 and 3 show a state after the insertion.

The tube unit 1 is composed of a pair of gutter-shaped plates 2 which are opposed to each other so as to form a fluid passage 3 between them. Each plate 2 is connected to a flat bottom plate portion 21, side plate portions 22 that are integrally erected on both side edges parallel to the longitudinal direction of the bottom plate portion 21, and one end of the side plate portion 22. And a flange portion 23 extending in parallel therewith. The pair of plates 2 are butted against each other in the depth direction, and the flange portions 23 are joined to each other to form the tube unit 1, and the inside thereof is formed in the fluid passage 3.

The end bottom plates 21 of the pair of plates are integrally formed with protrusions 24 that protrude inward. In the present embodiment, each plate 2 is provided with two projecting portions 24, but it may be one or three or more. These projecting portions 24 slightly project toward the fluid passage 3 side, and when the plates 2 are butted against each other, a gap is secured between them and the facing plate 2.

Further, in this embodiment, the projecting portion 24 extends from the longitudinal edge of each plate 2 in the longitudinal direction by an appropriate length.

The end portion of the tube unit 1 is inserted into the slot 41 of the header plate 4 when constructing the heat exchanger. The shape of the slot 41 is formed to be substantially the same as the sectional shape of the end portion of the tube unit 1 including the protrusion 24. When the tube unit 1 is inserted into the slot 41, the protrusion 24 traverses the slot 41 as shown in FIG.

In such a structure, since the projection 24 does not partially block the fluid passage 3, the flow passage resistance of the tube unit 1, and hence the flow passage resistance of the entire heat exchanger, is not significantly increased.

Further, the work hardening due to the formation of the protrusions 24 sufficiently reinforces the bottom plate portion 21 of each plate 2 to prevent the deflection and the like, so that a gap is formed between the bottom plate portion 21 and the slot 41 of the header plate 4 during brazing. There is no risk of leakage.

Further, since the protruding portion 24 is not abutted against the opposing plate 2, each plate 2 has some dimensional freedom while maintaining the sufficient deformation resistance strength. Therefore, even if a slight dimensional error occurs between the slot 41 and the tube unit 1,
It is easily absorbed by the above degrees of freedom. As a result, the ease of inserting the tube unit 1 is ensured, and the liquid-tight joint between the slot 41 and the tube unit 1 is also ensured.

4 to 6 show the tube unit according to the second embodiment of the present invention and the relationship between the tube unit and the header plate of the header. FIG. 4 shows a state before the tube unit is inserted into the slot of the header plate, and FIGS. 5 and 6 show a state after the insertion.

The tube unit 5 is composed of a pair of trough-shaped plates 6, and the pair of plates 6 are opposed to each other and bonded to each other so as to form a fluid passage 7 therebetween. Each plate 6 is connected to a flat bottom plate portion 61, side plate portions 62 that are integrally erected on both side edges parallel to the longitudinal direction of the bottom plate portion 61, and one end of the side plate portion 62. And a flange portion 63 extending in parallel therewith. The pair of plates 6 are butted against each other in the depth direction, and the flange portions 63 are joined to each other to form the tube unit 5, and the inside thereof is formed in the fluid passage 7.

At the end bottom plate portions 61 of the pair of plates 6,
Each of them is integrally formed with a protrusion 64 that protrudes inward. In the present embodiment, one protrusion 64 is formed on each plate 6, but two or more protrusions 64 may be formed. These projecting portions 64 slightly project toward the fluid passage 7 side, and when the plates 6 are butted against each other, a gap is secured between the projecting portions 64 and the facing plate 6.

Further, in the present embodiment, the projecting portion 64 is provided at the longitudinal end portion of each plate 6 at a position apart from the longitudinal end edge. Further, when the end of the tube unit 5 is inserted into the slot 81 of the header plate 8, as shown in FIG.
Is located between the edge of the plate 6 and the edge of the plate 6.

In such a structure, the same action and effect as in the first embodiment described above can be obtained, and in addition, since the projecting portion 64 is located between the slot 81 and the edge of the plate 6. The outer peripheral surface of the joint portion of the tube unit 5 with the header plate 8 is a flat surface. Therefore, the shape of the slot 81 formed in the header plate 8 may be a simple substantially rectangular shape, the formation of the slot 81 is further facilitated, and the shape between the cross-sectional shape of the tube unit 5 and the slot shape is small. This substantially eliminates the need for precise alignment, prevents dimensional inconsistencies from occurring, and improves the ease of inserting the tube unit 5.

FIG. 7 shows an example of a heat exchanger constructed by using the tube unit having the above-mentioned end structure. This heat exchanger 9 includes a tube unit 91,
First and second header bodies 92, 93, first and second header plates 94, 95, corrugated fins 96, fluid inlet pipe 97 and fluid outlet pipe 98.
Contains.

The tube unit 91 is shown in FIGS.
The tube unit 91 of the present embodiment has one end in the longitudinal direction opened and the other end closed, and the fluid passage formed therein has a substantially U shape. Thus, a partition (not shown) extending along the longitudinal direction is provided at the center of the tube unit 91. Therefore, one side of the open end of the tube unit 91 serves as a fluid inlet, and the other side serves as a fluid outlet.

The first header is substantially pipe-shaped and comprises a header plate 94 and a header body 92. The header plate 94 has slots (similar to the slots shown in FIGS. 1, 2, 4, and 5) formed at regular intervals. The first header has a fluid inlet pipe 97,
Also, a fluid outlet pipe 98 is attached, and a partition (not shown) for partitioning the inside of the header is provided between these pipes 97, 98. The second header is also substantially pipe-shaped and includes a header plate 95 and a header body 93.
The header plate 95 has slots formed at regular intervals. The first header and the second header communicate with each other. A plurality of tube units 91 are joined to the first and second headers at regular intervals by inserting one longitudinal end (open end) of each tube unit 91 into each slot of the first and second headers. It The corrugated fins 96 are arranged between the adjacent tube units 91 arranged at regular intervals.

In the present invention, the slot is not limited to the shape shown in FIGS. 1, 2, 4 and 5, but may be a burring slot 99 as shown in FIG. 8, for example. By doing so, it becomes easier to insert the tube unit.

Further, in each of the above embodiments, the header plate is formed in a flat plate shape, but it may be curved in order to improve pressure resistance.

[0030]

As described above, according to the heat exchanger tube unit of the present invention and the heat exchanger using the same, the end portions of the pair of plates constituting the tube unit are butted against the opposing plate. Since there is no inward protruding part, it is possible to improve the deformation resistance strength while suppressing the increase of flow path resistance and giving the necessary minimum degree of freedom, and the flow path of the heat exchanger as a whole. It is possible to simultaneously achieve reduction of resistance, liquid-tight connection between the tube unit and the header, and ease of insertion of the tube unit into the slot of the header.

[Brief description of drawings]

FIG. 1 is a partial perspective view showing a pre-insertion state of a tube unit and a header plate according to a first embodiment of the present invention.

FIG. 2 is a partial perspective view showing a state after the tube unit of the apparatus of FIG. 1 is inserted.

FIG. 3 is a partial side view of the device of FIG.

FIG. 4 is a partial perspective view showing a pre-insertion state of the tube unit and the header plate according to the second embodiment of the present invention.

5 is a partial perspective view showing a state after the tube unit of the apparatus of FIG. 4 is inserted.

FIG. 6 is a partial side view of the apparatus of FIG.

FIG. 7 is a perspective view of a heat exchanger according to an embodiment of the present invention.

FIG. 8 is a partial perspective view of a header plate showing a modified example of the slot.

FIG. 9 is a partial perspective view showing a state before insertion of a conventional tube unit and a header plate.

FIG. 10 is a partial perspective view showing a state after the tube unit of the apparatus of FIG. 9 is inserted.

[Explanation of symbols]

 1, 5, 91 Tube unit 2, 6 Plate 3, 7 Fluid passage 4, 8, 94, 95 Header plate 21, 61 Bottom plate part 22, 62 Side plate part 23, 63 Flange part 24, 64 Projection part 41, 81, 99 Slots 92, 93 Header body 96 Corrugated fins 97 Fluid inlet pipe 98 Fluid outlet pipe

Claims (6)

[Claims] 1. A pair of gutter-shaped plates, which are opposed to each other so as to form a fluid passage therebetween and are joined to each other, have a longitudinal end inserted into a slot formed in a header. A tube unit for a heat exchanger, wherein in the tube unit for an exchanger, a projecting portion that projects inwardly of the tube unit with a gap between the pair of plates is provided at a longitudinal end of the pair of plates. 2. The tube unit for a heat exchanger according to claim 1, wherein the protruding portion extends in the longitudinal direction from longitudinal edges of the pair of plates. 3. The tube unit for a heat exchanger according to claim 1, wherein the protruding portion is formed at a position apart from a longitudinal edge of longitudinal ends of the pair of plates. 4. The protrusion of claim 3, wherein the protrusion is formed so as to be located between the slot and a longitudinal edge of the plate when the tube unit is inserted into the slot of the header. Tube unit for heat exchanger. 5. The tube unit for a heat exchanger according to claim 1, which is made of aluminum or an aluminum alloy. 6. A heat exchanger comprising: the tube unit for a heat exchanger according to claim 1; and a header having a slot into which a longitudinal end of the tube unit is inserted. vessel.