JP2006284107A - Heat exchanger - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To reduce stress in all regions in a cross direction Z of a tube 10 while preventing stress concentration on the end in the cross direction Z of the tube 10 even when a temperature difference between the tubes 10 is greater. <P>SOLUTION: A rib 223 is provided extending from both ends in the cross direction Z of a tube insertion hole to the outside to increase the peripheral rigidity of the tube insertion hole, and so the tube insertion hole is hard to deform therearound into an approximately circular arc shape. Thus, an elongation difference between the center and the end in the cross direction Z of the tube 10 is smaller to prevent stress concentration on the end of the tube. Both ends in the cross direction Z of the rib 223 are not connected to an inside wall portion 23 and so a face 226 between the rib 223 and the inside wall portion 23 is easily deformable in a longitudinal direction X of the tube. Thus, the deformation of the face 226 absorbs the thermal distortion of the tube 10 to reduce stress in all regions of the tube. <P>COPYRIGHT: (C)2007,JPO&INPIT

Description

  The present invention relates to a heat exchanger, and is effective when applied to a radiator that cools cooling water by exchanging heat between cooling water and air of a water-cooled internal combustion engine.

  In the conventional heat exchanger, a large number of tubes and a large number of corrugated fins are alternately stacked to constitute a core portion. And the tank is arrange | positioned at the tube longitudinal direction edge part in the tube. The tank includes a core plate into which a tube is inserted and a tank portion that is caulked and fixed to the core plate to form a space in the tank together with the core plate.

In the core plate, a tube insertion hole into which a tube is inserted is formed in the tube joint surface, and a wall portion that is bent substantially perpendicular to the tube joint surface is formed on the outer periphery of the tube joint surface. Furthermore, a rib is formed on the tube joint surface of the core plate in parallel with the tube insertion hole, and both ends of the rib are connected to the wall portion, thereby increasing the rigidity of the core plate and mainly deforming the core plate due to internal pressure. (See, for example, Patent Document 1).
JP 2004-219044 A

  By the way, when this heat exchanger is used as a vehicle radiator, the temperature difference between the cooling water and the outside air is large especially in winter, so that the tube is easily damaged by thermal strain. Furthermore, in the cross flow type where the longitudinal direction of the tube tends to match the shape of the vehicle grille opening, there are tubes that are susceptible to cooling air and tubes that are difficult to receive cooling air, and the temperature difference between the tubes tends to increase. The tube is easily damaged by thermal strain.

  If the tank is flexible in the tube stacking direction, in other words, if the tank can be deformed independently in the tube longitudinal direction at each part in the tube stacking direction, the thermal strain due to the temperature difference between the tubes is reduced. In reality, it alone cannot absorb thermal strain.

  Here, in the heat exchanger in which the rib is not formed on the core plate, as shown in FIG. 11, the tube joining surface 22 of the core plate 20 is deformed in the tube longitudinal direction X, in other words, the core plate 20. When the tube joint surface 22 is deformed into a substantially arc shape, the thermal strain that could not be absorbed by the deformation of the tank described above is absorbed. In addition, in FIG. 11, the broken line shows the state when there is no temperature difference between the tubes 10, and the solid line shows the state when the temperature difference between the tubes is large.

  However, in the heat exchanger in which the ribs are not formed on the core plate 20, when the temperature difference between the tubes is large, the tube joining surface 22 of the core plate 20 is deformed into a substantially arc shape. The elongation in the tube width direction Z end portion is larger than that in the width direction Z center portion, and the influence of thermal strain is concentrated on the tube width direction Z end portion of the tube 10, and the tube width direction Z end portion of the tube 10 is concentrated. In particular, there is a problem that high stress is generated.

  On the other hand, in the heat exchanger described in Patent Document 1, since both ends of the rib formed on the core plate are connected to the wall portion to increase the rigidity of the core plate, the core plate is difficult to deform in the longitudinal direction of the tube. Therefore, there is a problem in that the heat-strain absorption margin of the tube is lowered, and an equally high stress is generated in the entire tube width direction of the tube.

  In view of the above points, an object of the present invention is to reduce stress in the entire tube width direction of the tube while preventing stress concentration in the tube width direction end of the tube.

  In order to achieve the above object, in the invention according to claim 1, a flat tube (10) arranged in a large number of layers, and an end portion in the tube longitudinal direction (X) of the tube (10) are arranged. A tank (2, 3) communicating with the tube (10) is provided, and an end of the tube (10) in the tube longitudinal direction (X) is a tube insertion hole in the tube joining surface (22) of the tank (2, 3). In the heat exchanger inserted and joined in (221), when the direction perpendicular to both the tube stacking direction (Y) and the tube longitudinal direction (X) is the tube width direction (Z), the tube joining surface (22 ) Is formed with a plurality of ribs (223) extending in the tube width direction (Z), and both ends of the rib (223) in the tube width direction (Z) are in the tube insertion hole (221). The tube extends in the tube width direction (Z) outside from both ends in the width direction (Z), and the tube joining surface (22) has a tube outside the tube width direction (Z) both ends in the rib (223). There is a deformation allowing portion (226) that facilitates deformation of the joint surface (22) in the tube longitudinal direction (X).

  According to this, since the rib extends to the outside in the tube width direction from the tube insertion hole, the vicinity of the tube insertion hole is not easily deformed into a substantially arc shape, and therefore, the elongation is uniform throughout the tube width direction in the tube. Stress concentration at the end in the tube width direction can be prevented.

  In addition, since the thermal strain of the tube is absorbed by deformation of the deformation-permitting portion existing on the outer side of both ends of the rib in the tube width direction, the stress can be reduced in the entire tube width direction of the tube.

  In this way, stress can be reduced in the entire tube width direction of the tube while preventing stress concentration on the tube width direction end of the tube.

  In the invention described in claim 2, the flat tube (10) arranged in a number of layers and the tube (10) are arranged at the end of the tube longitudinal direction (X) and orthogonal to the tube longitudinal direction (X). Tanks (2, 3) that extend in the direction and communicate with a large number of tubes (10), and the ends of the tubes (10) in the tube longitudinal direction (X) are connected to the tube joining surfaces ( 22) In the heat exchanger inserted and joined in the tube insertion hole (221), when the tube width direction (Z) is the direction orthogonal to both the tube stacking direction (Y) and the tube longitudinal direction (X) The tank (2, 3) has a wall portion (23) bent from the outer peripheral portion of the tube joint surface (22), and the tube joint surface (22) has a plurality extending in the tube width direction (Z). A rib (223) is formed, and both ends of the rib (223) in the tube width direction (Z) extend outward from the tube width direction (Z) in the tube insertion hole (221). The both ends of the rib (223) in the tube width direction (Z) are not connected to the wall (23).

  According to this, since the rib extends to the outside in the tube width direction from the tube insertion hole, the vicinity of the tube insertion hole is not easily deformed into a substantially arc shape, and therefore, the elongation is uniform throughout the tube width direction in the tube. Stress concentration at the end in the tube width direction can be prevented.

  In addition, since both ends of the rib in the tube width direction are not connected to the wall, the core plate is easily deformed in the tube longitudinal direction, and the deformation absorbs the thermal strain of the tube, reducing the stress in the entire tube width direction of the tube. can do.

  In this way, stress can be reduced in the entire tube width direction of the tube while preventing stress concentration on the tube width direction end of the tube.

  According to a third aspect of the present invention, in the heat exchanger according to the first or second aspect, a rib (223) is provided between adjacent tube insertion holes (221). According to this, it can suppress reliably that the tube insertion hole vicinity deform | transforms into a substantially circular arc shape.

  According to a fourth aspect of the present invention, in the heat exchanger according to any one of the first to third aspects, the tank (2, 3) includes a metal core to which the tube (10) is inserted and joined. It has a plate (20) and a resin tank part (21) joined to the core plate (20) to form a space (20a) in the tank (2, 3) together with the core plate (20). And

  Thus, when the tank part is made of resin, the rigidity of the metal core plate greatly affects the rigidity of the entire tank. As a result, in a heat exchanger in which the tank portion is made of resin, the effect of installing the rib on the metal core plate is relatively increased. Therefore, the present invention is particularly effective for a heat exchanger in which the tank portion is made of resin and the core plate has high rigidity.

  In addition, the code | symbol in the bracket | parenthesis of each said means shows the correspondence with the specific means as described in embodiment mentioned later.

(First embodiment)
In this embodiment, the heat exchanger according to the present invention is applied to a radiator for cooling a water-cooled internal combustion engine, and FIG. 1 is a front view of the heat exchanger according to the first embodiment of the present invention. 2 is a perspective sectional view of a tank and a tube in the heat exchanger of FIG. 1, FIG. 3A is a front view of the core plate alone of FIG. 2, FIG. 3B is a bottom view of FIG. Is a cross-sectional view taken along the line AA in FIG. 3, FIG. 5 is a cross-sectional view taken along the line BB in FIG. 3, and FIG. 6 is a schematic view of the deformation state of the core plate and the tube when the temperature difference between the tubes is large. FIG.

  As shown in FIGS. 1 and 2, the heat exchanger includes a rectangular parallelepiped core portion 1, and the core portion 1 includes a large number of tubes 10 and a large number of corrugated fins 11 stacked alternately in the vertical direction. Configured. The stacking direction of the tube 10 and the corrugated fin 11 is hereinafter referred to as a tube stacking direction Y.

  The corrugated fins 11 are made of an aluminum alloy and are formed in a corrugated shape to promote heat exchange between air and cooling water.

  The tube 10 has a passage through which cooling water of a water-cooled internal combustion engine (not shown) mounted on the vehicle flows, and is formed by bending or welding or brazing an aluminum alloy plate material into a predetermined shape. Is done.

  In this embodiment, the tube 10 has a flat shape in which the longitudinal direction (hereinafter referred to as the tube longitudinal direction X) coincides with the horizontal direction and the cross-sectional shape thereof coincides with the air flow direction C. Is formed. The direction orthogonal to both the tube stacking direction Y and the tube longitudinal direction X is hereinafter referred to as a tube width direction Z. Incidentally, the tube width direction Z coincides with the major axis direction of the tube 10 and the air flow direction C.

  At both ends of the tube 10 in the tube longitudinal direction X, tanks 2 and 3 extending in a direction substantially orthogonal to the tube longitudinal direction X and having a space formed therein are disposed. The ends of the tubes 10 in the longitudinal direction X of the tube 10 are inserted into and joined to the tanks 2 and 3 in tube insertion holes 221 (details will be described later). It communicates with the space.

  One tank 2 distributes and supplies the high-temperature cooling water flowing out from the engine to a number of tubes 10. The one tank 2 is provided with an inlet pipe 20 connected to the cooling water outlet side of the internal combustion engine via a hose (not shown).

  The other tank 3 collects and collects the cooling water cooled by heat exchange with air and drains it toward the internal combustion engine. The other tank 3 is provided with an outlet pipe 30 connected to the coolant inlet side of the internal combustion engine via a hose.

  Side plates 4 that reinforce the core portion 1 are disposed at both ends of the core portion 1 in the tube stacking direction Y. The side plate 4 is made of an aluminum alloy, extends in a direction parallel to the tube longitudinal direction X, and both ends thereof are connected to the tanks 2 and 3.

  The tanks 2 and 3 have a core plate 20 in which the tube 10 and the side plate 4 are inserted and fixed, a tank portion 21 that forms a space 2a in the tanks 2 and 3 together with the core plate 20, and a packing (not shown). Configured.

  In the present embodiment, the core plate 20 is made of an aluminum alloy, the tank portion 21 is made of a resin such as glass fiber reinforced nylon 66, and the rubber packing for maintaining hermeticity is bonded to the core plate 20 and the tank portion 21. In a state of being sandwiched between them, a projecting piece 251 of the core plate 20 to be described later is plastically deformed so as to press against the tank portion 21, and the tank portion 21 is caulked and fixed to the core plate 20.

  As shown in FIGS. 3 to 5, the core plate 20 has a tube joining surface 22 to which a tube is joined, and the cross section of the end of the tank portion 21 and the packing is inserted around the tube joining surface 22. A rectangular groove 20a is formed over the entire circumference.

  The groove 20a is formed by three surfaces. That is, an inner wall portion 23 that is bent substantially vertically from the outer peripheral portion of the tube joining surface 22 and extends in the tube longitudinal direction X, and a bottom wall portion 24 that is bent substantially vertically from the inner wall portion 23 and extends in the tube stacking direction Y. A groove 20 a is formed by the outer wall portion 25 that is bent substantially perpendicularly from the bottom wall portion 24 and extends in the tube longitudinal direction X. A large number of protruding pieces 251 are formed at the end of the outer wall portion 25. The inner wall portion 23 corresponds to the wall portion of the present invention.

  A number of tube insertion holes 221 into which the tube 10 is inserted and brazed are formed along the tube stacking direction Y on the tube joint surface 22 of the core plate 20. Further, one side plate insertion hole 222 into which the side plate 4 is inserted and brazed is formed on each end of the tube joining surface 22 in the tube stacking direction Y. The tube insertion hole 221 and the side plate insertion hole 222 are formed by punching.

  Furthermore, ribs 223 that protrude from the tube joint surface 22 to the outside of the tank are pressed, for example, between the tube insert holes 221 adjacent to each other and between the tube insert holes 221 and the side plate insert holes 222. Is formed by.

  By punching the insertion holes 221, 222, the periphery of the insertion holes 221, 222 is convex toward the inside of the tank. Since the tube pitch in this embodiment is relatively large, the reference surface 224 remains between the convex portions around the insertion holes 221 and 222 and the ribs 223. The boundary line 225 between the convex portion around the tube insertion hole 221 and the reference surface 224 when the tube joining surface 22 is viewed from the inside of the tank is hereinafter referred to as an insertion hole boundary line 225.

  Each insertion hole 221, 222 and rib 223 extend long in the tube width direction Z, and the rib 223 is longer than each insertion hole 221, 222. Moreover, the tube width direction Z both ends in the rib 223 are extended to the tube width direction Z outer side rather than the tube width direction Z both ends in each insertion hole 221,222. More specifically, the tube width direction Z both ends of the rib 223 extend to the outside in the tube width direction Z rather than the tube width direction Z both ends of the insertion hole boundary line 225.

  Incidentally, the dimension in the tube width direction Z from the tube width direction Z end portion to the inner wall portion 23 in the tube insertion hole 221 is defined as the insertion hole outer interval L1, and from the tube width direction Z end portion in the tube insertion hole 221 to the rib 223. When the dimension in the tube width direction Z to the tube width direction Z end is the rib protrusion length L2, the rib protrusion length L2 is preferably about 1/3 of the insertion hole outer space L1.

  Both ends of the rib 223 in the tube width direction Z do not reach the inner wall portion 23. In other words, the tube width direction Z both ends of the rib 223 are not connected to the inner wall portion 23. Therefore, a flat surface 226 exists outside the tube width direction Z both ends of the insertion holes 221 and 222 and the ribs 223 and over the entire region in the tube stacking direction Y on the tube joining surface 22. The flat surface 226 facilitates deformation of the tube joint surface 22 in the tube longitudinal direction X, as will be described later, and corresponds to a deformation allowing portion of the present invention.

  Next, the effect of this embodiment is demonstrated.

  In the present embodiment, both ends of the rib 223 in the tube width direction Z extend to the outside in the tube width direction Z rather than both ends of the tube width direction Z in the tube insertion hole 221, and the rigidity around the tube insertion hole 221 is increased. Therefore, even when the temperature difference between the tubes 10 is large, as shown in FIG. 6, the vicinity of the tube insertion hole 221 is hardly deformed into a substantially arc shape, and a state close to a straight line is maintained. Therefore, the difference in elongation between the tube width direction Z center portion and the tube width direction Z end portion of the tube 10 is reduced, that is, the elongation is uniform in the entire tube width direction Z region of the tube 10. Therefore, stress concentration on the tube width direction Z end portion of the tube 10 can be prevented.

  Moreover, since both ends of the rib width 223 in the tube width direction Z are not connected to the inner wall portion 23, the flat surfaces 226 existing outside the tube width direction Z both ends of the insertion holes 221 and 222 and the rib 223 are It can be easily deformed in the longitudinal direction X. Therefore, when the temperature difference between the tubes 10 is large, the core plate 20 is deformed in the tube longitudinal direction X by the deformation of the flat surface 226 as shown in FIG. 6, and the deformation of the tube 10 is absorbed by the deformation. Thus, the stress can be reduced in the entire tube width direction Z of the tube 10.

  Thus, even when the temperature difference between the tubes 10 is large, stress can be reduced in the tube width direction Z entire region Z of the tube 10 while preventing stress concentration on the tube width direction Z end portion of the tube 10. it can.

  Moreover, since the rib 223 is formed between the adjacent tube insertion holes 221, the rigidity around the tube insertion holes 221 is reliably increased, and the vicinity of the tube insertion holes 221 is reliably suppressed from being deformed into a substantially arc shape. be able to.

  Further, when both ends of the tube width direction Z in the rib 223 are extended to the outside in the tube width direction Z rather than both ends of the tube width direction Z in the insertion hole boundary line 225, the insertion hole It deforms outside the boundary line 225, and therefore stress concentration on the insertion hole boundary line 225, which is a bent portion, can be prevented.

Furthermore, by setting the rib protrusion length L2 to about 1/3 of the insertion hole outer interval L1, the rigidity around the tube insertion hole 221 is increased, and the vicinity of the tube insertion hole 221 is prevented from being deformed into a substantially arc shape. The flat surface 226 can be easily deformed in the tube longitudinal direction X.
(Second Embodiment)
A second embodiment of the present invention will be described. FIG. 7 is a bottom view of a single core plate in a heat exchanger according to the second embodiment of the present invention, and FIG. 8 is a cross-sectional view taken along the line DD of FIG. In addition, the same code | symbol is attached | subjected to the same or equivalent part as 1st Embodiment, and the description is abbreviate | omitted.

  In the first embodiment, the tube insertion hole 221 is formed by punching, but the tube insertion hole 221 may be formed by burring as in the second embodiment shown in FIGS.

(Third embodiment)
A third embodiment of the present invention will be described. FIG. 9 is a bottom view of a single core plate in a heat exchanger according to the third embodiment of the present invention, and FIG. 10 is a cross-sectional view taken along line EE of FIG. In addition, the same code | symbol is attached | subjected to the same or equivalent part as 1st Embodiment, and the description is abbreviate | omitted.

  When the pitch between adjacent tubes 10 is narrow, as shown in FIGS. 9 and 10, there is no reference plane 224 between the tube insertion hole 221 and the rib 223, and the tube insertion hole 221 and the rib 223 are It may be a connected shape. In this case, the tube insertion hole 221 is formed at the peak of the mountain shape.

(Other embodiments)
In each of the above embodiments, the ribs 223 are formed in the entire area between the adjacent tube insertion holes 221. However, even if the ribs 223 are formed only in a part (for example, every other) between the adjacent tube insertion holes 221. Good.

It is a front view of the heat exchanger which concerns on 1st Embodiment of this invention. It is a perspective sectional view of a tank and a tube in the heat exchanger of FIG. (A) is the front view of the core plate single-piece | unit of FIG. 2, (b) is a bottom view of (a). It is sectional drawing which follows the AA line of FIG. It is sectional drawing which follows the BB line of FIG. It is a figure which shows typically the deformation | transformation state of the core plate and tube in the heat exchanger of FIG. It is a bottom view of the core plate single-piece | unit in the heat exchanger which concerns on 2nd Embodiment of this invention. It is sectional drawing which follows the DD line | wire of FIG. It is a bottom view of the core plate single-piece | unit in the heat exchanger which concerns on 3rd Embodiment of this invention. It is sectional drawing which follows the EE line | wire of FIG. It is a figure which shows typically the deformation | transformation state of the core plate and tube in the conventional heat exchanger.

Explanation of symbols

  2, 3 ... Tank, 10 ... Tube, 22 ... Tube joint surface, 221 ... Tube insertion hole, 223 ... Rib, 226 ... Flat surface (deformation allowable part), X ... Tube longitudinal direction, Y ... Tube stacking direction, Z … Tube width direction.

Claims (4)

A flat tube (10) arranged in multiple layers;
A tank (2, 3) disposed at an end of the tube (10) in the tube longitudinal direction (X) and communicating with the multiple tubes (10);
In the heat exchanger in which the tube longitudinal direction (X) end of the tube (10) is inserted and joined to the tube insertion hole (221) of the tube joining surface (22) of the tank (2, 3),
When the direction perpendicular to both the tube stacking direction (Y) and the tube longitudinal direction (X) is the tube width direction (Z),
A plurality of ribs (223) extending in the tube width direction (Z) are formed on the tube joining surface (22),
The tube width direction (Z) both ends in the rib (223) extend to the tube width direction (Z) outside than the tube width direction (Z) both ends in the tube insertion hole (221),
The tube joining surface (22) can be easily deformed in the tube longitudinal direction (X) of the tube joining surface (22) at a portion outside the both ends of the tube width direction (Z) of the rib (223). A heat exchanger characterized in that there is a deformable portion (226) that is present. A flat tube (10) arranged in multiple layers;
Tanks (2, 3) arranged at the end of the tube (10) in the tube longitudinal direction (X) and extending in a direction perpendicular to the tube longitudinal direction (X) and communicating with the multiple tubes (10). Prepared,
In the heat exchanger in which the tube longitudinal direction (X) end of the tube (10) is inserted and joined to the tube insertion hole (221) of the tube joining surface (22) of the tank (2, 3),
When the direction perpendicular to both the tube stacking direction (Y) and the tube longitudinal direction (X) is the tube width direction (Z),
The tank (2, 3) has a wall portion (23) bent from the outer peripheral portion of the tube joint surface (22),
A plurality of ribs (223) extending in the tube width direction (Z) are formed on the tube joining surface (22),
The tube width direction (Z) both ends in the rib (223) extend to the tube width direction (Z) outside than the tube width direction (Z) both ends in the tube insertion hole (221),
The tube width direction (Z) both ends in the said rib (223) are not connected to the said wall part (23), The heat exchanger characterized by the above-mentioned. The heat exchanger according to claim 1 or 2, wherein the rib (223) is provided between the adjacent tube insertion holes (221). The tank (2, 3) includes a metal core plate (20) into which the tube (10) is inserted and joined, and the tank together with the core plate (20) joined to the core plate (20). The heat exchanger according to any one of claims 1 to 3, further comprising a resin tank portion (21) that forms a space (20a) in (2, 3).

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