JP2009168382A - Heat exchanger - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To dispense with a conventional spacer plate which is a factor in a brazing failure and a fall of heat exchange efficiency. <P>SOLUTION: An oil cooler comprises a bottomed cylindrical casing 1 through which cooling water flows; a cover plate 4 closing the opening face of the casing 1; and a core 3 through the inside of which oil flows. The core 3 is formed by laminating a plurality of flat tubes 2 formed by joining first plates 21 and second plates 22, in multiple stages and integrating them by brazing-joining. A large number of embosses 26 are formed at the first plate 21 to ensure a clearance between the adjacent tubes 2. The uppermost second plate 22A differs from others and has a large number of embosses 46 projected to the bottom wall 1a side of the casing 1. The conventional spacer plate is thereby dispensed with. <P>COPYRIGHT: (C)2009,JPO&INPIT

Description

  The present invention relates to a heat exchanger used as an oil cooler of an internal combustion engine, for example.

Two metal plates are joined at the periphery to form a flat tube, and a plurality of tubes are stacked in multiple stages to form a heat exchange core, and the core is housed in a bottomed cylindrical casing. A heat exchanger is disclosed in, for example, Patent Document 1 previously proposed by the present applicant. In this Patent Document 1, the flat tubes at each stage have basically the same shape, one plate has a flat shape, and a number of embosses are formed on the other plate, and the tips of the embosses are adjacent to each other. By contacting the surface of the flat plate of the tube, a gap through which one fluid flows is secured between the tubes of each stage. In order to ensure a similar gap between the flat plate of the first stage and the bottom surface of the casing facing the plate, the spacer plate formed with a large number of embosses made of different parts is provided with a flat plate of the first stage. It is superimposed on the plate. Each of these plates is simultaneously brazed and joined in the furnace together with the casing and the cover plate that closes the opening surface. In addition, the mutual joining via the said embossing has also contributed to the rigidity improvement as the whole core.
JP 2006-10192 A

  In a heat exchanger equipped with a spacer plate as described above separately from the core plate, the position of the spacer plate is not strictly regulated during assembly. There is a concern that poor soldering may occur. In addition, the number of parts is not only large, but the first flat plate and the spacer plate are overlapped, so that it is substantially thick, and the heat exchange efficiency is partially reduced. There was a problem.

  Therefore, in the present invention, the same function is given to the first stage plate or the bottom wall of the casing without using the spacer plate.

  That is, the present invention includes a bottomed cylindrical casing having an open end, a cover plate that closes an opening surface of the casing and defines a space through which the first fluid flows together with the casing, A heat exchanger comprising a core housed in a flat tube comprising a first plate and a second plate joined to each other at a peripheral edge thereof, and a space inside thereof communicates with each other. Heat exchange in which the second fluid flows through the space inside each tube and the first fluid flows through the gap between adjacent tubes. In order to form the gap between adjacent tubes, the first plate positioned relatively to the cover plate in each tube is directed toward the cover plate. And a large number of embossing is bulged formed projecting I, the tip of the embossing is in contact respectively with the flat surface of the second plate in the adjacent tubes person. Further, the tip of the emboss of the first plate of the tube at the last stage of the core composed of a plurality of stages of tubes is in contact with the cover plate.

  In the first aspect of the present invention, a large number of embosses projecting toward the bottom surface side of the casing are bulged and formed on the second plate of the tube at the first stage, and the tip of the embossing contacts the bottom surface. It touches.

  Preferably, the first plate has the same shape in all stages of tubes, and the second plate has the same shape in all stages of tubes other than the first stage. That is, only the second plate of the first stage has a different shape from the second plate of the other stage.

  The contact portions at the tips of the embosses in these plates are brazed and joined.

  The embosses each have, for example, a truncated cone shape.

    Further, in the second aspect of the present invention, in place of the emboss formation in the second plate of the first stage tube, a large number of embosses protruding toward the cover plate are formed on the bottom wall of the casing. The tip of the emboss is in contact with the flat surface of the second plate of the first stage tube. The tip of this emboss is also joined by brazing.

  In the heat exchanger of the present invention, a spacer plate made of a separate part on the bottom surface side of the casing is unnecessary, and there is no fear of poor soldering due to the positional deviation, the number of parts is reduced, and the addition of the spacer plate Deterioration of heat exchange efficiency can be avoided. Further, in any of the abutting portions of the emboss, the counterpart surface that receives the tip of the emboss is basically a flat surface, and stable brazing joining is possible.

  Hereinafter, an embodiment of the present invention will be described in detail with reference to the drawings.

  1 and 2 show an embodiment in which the present invention is configured as an oil cooler attached to a cylinder block of an internal combustion engine. The oil cooler includes a casing 1 having a cup shape, that is, a bottomed cylindrical shape, a core 3 including a plurality of flat tubes 2 accommodated in the casing 1, a cover plate 4 that covers the opening surface of the casing 1, The packing guide 5 stacked on the lower surface of the cover plate 4 and the sheet plate 6 stacked on the upper surface of the bottom wall 1a of the casing 1 are roughly configured. In order to facilitate understanding, in the following description, for the sake of convenience, the directions of “up” and “down” are used with reference to the posture of FIG.

  In the casing 1, cooling water flows through an internal space 7, and a cooling water inlet 8 and a cooling water outlet 9 are provided on the outer peripheral surface. In addition, a mounting hole 10 is formed in the center of the bottom wall 1a of the casing 1 and the seat plate 6, and is inserted through an opening similarly provided in the center of the core 3, the packing guide 5, and the like. The entire oil cooler is attached to a cylinder block (not shown) by a center bolt (not shown). In this mounted state, a cartridge type oil filter (not shown) is mounted on the seat plate 6, and the oil cooler as a whole has an opening provided at a position eccentric to one side of the cover plate 4. 11, the opening at the center of the packing guide 5 through which the center bolt passes is an oil outlet 12 to the cylinder block side. Further, oil communication holes 13 and 14 to an oil filter (not shown) are formed in the bottom wall 1a of the casing 1 and the seat plate 6, respectively.

  In the present embodiment, the core 3 includes twelve flat tubes 2 stacked in the axial direction of a cylindrical oil cooler. Each tube 2 is formed at the first stage (the uppermost stage in the figure). The first and second plates 21 and 22 have the same configuration except for the first plate 21 and the second plate 22 on the upper side. These first and second round plates 21 and 22 have fitting walls 21a and 22a having inclined tapered surfaces on their outer peripheral edges, and these fitting walls 21a and 22a are fitted to each other. By doing so, the disk-shaped tube 2 which has a flat space is comprised. In addition, you may make it enclose the fin plate of an appropriate shape inside each tube 2 as needed.

  FIG. 3 is a plan view of the first plate 21 as viewed from the upper side of FIG. 1. A central opening 23 through which oil flows is formed at the center of the first plate 21 having a true circle shape. In addition, two communication holes 24 and 25 are formed at positions approximately 180 ° apart. As shown in FIG. 1, the opening edge 23 a of the central opening 23 is bent in a short cylindrical shape downward, and when the core 3 is laminated in multiple stages, the cylindrical opening edge 23 a of each tube 2. Are successively arranged to form one cylindrical passage. Further, the opening edges 24a and 25a of the communication holes 24 and 25 protrude in a step shape downward. Further, a large number of fine embosses 26 are pressed on the entire surface of the first plate 21. The emboss 26 has a truncated cone shape, and protrudes downward, that is, toward the cover plate 4.

  FIG. 4 is a plan view of the second plate 22 as viewed from the upper side of FIG. 1, and a central opening portion through which the cylindrical opening edge 23a can pass at the central portion of the second plate 22 having a true circle shape. 28 is formed as an opening, and two communication holes 29 and 30 are formed at positions approximately 180 ° apart. As shown in FIG. 1, the opening edge 28 a of the central opening 28 protrudes in a step shape so as to come into contact with the first plate 21 of the adjacent tube 2. A stepped portion 31 that is recessed downward is formed so as to surround the entire circumference of the opening edge 28a. As shown in FIG. 1, the step portion 31 is joined to the first plate 21 and partitions the inner peripheral side of the space in the tube 2. As is apparent from FIG. 4, the second plate 22 has a flat surface with no irregularities except for the step portion 31 and the three openings 28, 29, and 30.

  The first plate 21 and the second plate 22 are made of a clad material provided with a brazing material layer on both sides of the base material together with the cover plate 4 and the like, and are temporarily assembled as shown in FIG. The parts are brazed by heating in a furnace. At the time of this brazing and joining, an appropriate pressure is applied by a weight in the axial direction of the oil cooler (up and down direction in FIG. 1) to keep the parts in close contact.

  In the state where the first plate 21 and the second plate 22 are combined and stacked in multiple stages, as shown in FIG. 1, the fitting walls 21a and 22a of both the plates 21 and 22 are fitted to each other and the inner peripheral side The step portion 31 abuts on the first plate 21 to form one tube 2. Between the adjacent tubes 2, the emboss 26 of the first plate 21 of the tube 2 positioned above abuts the upper surface of the second plate 22 of the tube 2 positioned below and the second of the tubes 2 positioned below is located. The opening edge 28a of the central opening 28 of the two plates 22 contacts the lower surface of the first plate 21 of the tube 2 positioned above, and further, as shown in the sectional view of FIG. The opening edges 24a and 25a of the communication holes 24 and 25 of the 1 plate 21 are in contact with the upper surface of the second plate 22 of the tube 2 positioned below, so that a gap between the tubes 2 is secured. Note that the contact portions of these portions are finally brazed and joined. Here, since the many embosses 26 of the 1st plate 21 contact | abut on the plane of the 2nd plate 22 between adjacent tubes 2, the stable positional relationship is always acquired.

  Further, the relationship between the tube 2 at the last stage, that is, the lowermost stage in FIG. 1 and the cover plate 4 is the same as the relationship between the two tubes 2, and the first plate 21 is formed on the upper surface of the cover plate 4 forming a flat surface. The large number of the embosses 26 and the opening edges 24a and 25a of the communication holes 24 and 25 are in contact with each other, and a similar gap is secured. Further, the opening edge of the center opening of the cover plate 4 rises upward in a stepped manner, and supports the periphery of the center opening 23 of the first plate 21. These contact portions are also finally joined by brazing.

  On the other hand, in the first stage, that is, the uppermost tube 2 in FIG. 1, the first plate 21 is the same as the first plate 21 of the other tubes 2, but the second plate 22 </ b> A combined therewith is It is slightly different from the second plate 22 of the other tube 2. That is, FIG. 5 shows a plan view of the second plate 22A as viewed from the upper side of FIG. 1. Like the other second plates 22, the center of the second plate 22A having a true circle is centered. An opening 41 is formed, and two communication holes 42 and 43 are formed at positions approximately 180 ° apart. As shown in FIG. 1, the opening edge 41 a of the center opening 41 protrudes upward in a step shape so as to abut on the peripheral edge of the mounting hole 10 in the bottom wall 1 a of the casing 1. It stands up in a short cylindrical shape so that it can enter. A stepped portion 44 that is recessed downward is formed so as to surround the entire periphery of the opening edge 41a. The step portion 44 has the same shape as the step portion 31 of the other second plate 22, and is joined to the first plate 21 as shown in FIG. 1 to partition the inner peripheral side of the space in the tube 2. Further, the opening edges 42 a and 43 a of the communication holes 42 and 43 protrude upward in a step shape so as to contact the lower surface of the bottom wall 1 a of the casing 1. The uppermost second plate 22A, like the first plate 21, has a large number of fine embosses 46 pressed on the entire surface. The embossing 46 has a truncated cone shape and protrudes on the side opposite to the embossing 26 of the first plate 21, that is, toward the bottom wall 1 a side of the casing 1.

  Therefore, in the uppermost tube 2, the embossing 46 of the second plate 22 </ b> A contacts the lower surface of the flat bottom wall 1 a of the casing 1, and the opening edge 41 a of the central opening 41 and the opening edges of the communication holes 42 and 43. Similarly, 42a and 43a (see FIG. 2) abut against the lower surface of the bottom wall 1a, and a gap through which cooling water flows is secured. These contact portions are also finally joined by brazing.

  Thus, in the above embodiment, the embossing 46 is provided on the second plate 22A of the uppermost tube 2, thereby eliminating the need for the conventional spacer plate, reducing the number of components, and adding the spacer plate. A decrease in heat exchange efficiency is avoided. Further, the second plate 22A provided with the emboss 46 is combined with the first plate 21 so that its position is defined, and the other surface with which the emboss 46 abuts is a simple flat surface. It is possible to realize brazing with a low defect occurrence rate without the need for accurate positioning or the like.

  Next, FIG. 6 shows an essential part of the second embodiment of the present invention. In this embodiment, the tube 2 at the uppermost stage of the core 3 is attached to the bottom wall 1a of the adjacent casing 1 and the tube 2 is attached. A large number of embosses 51 projecting toward the press are pressed. In this case, the second plate 22 of the uppermost tube 2 can be the same as the second plate 22 of the other tubes 2, and the upper surface with which the emboss 51 abuts is a flat surface. The abutting portions of the emboss 51 are also brazed and joined together.

BRIEF DESCRIPTION OF THE DRAWINGS Sectional drawing of the oil cooler used as one Example of this invention. Sectional drawing which shows the cross section along a pair of communicating hole. The top view of a 1st plate. The top view of the 2nd plate. The top view of the 2nd plate in the uppermost tube. Sectional drawing of the principal part which shows 2nd Example of this invention.

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 ... Casing 2 ... Tube 3 ... Core 4 ... Cover plate 21 ... 1st plate 22, 22A ... 2nd plate 26, 46, 51 ... Emboss

Claims (4)

A bottomed cylindrical casing having one open end, a cover plate that closes the opening surface of the casing and defines a space through which the first fluid flows together with the casing, and a core accommodated in the space; The core is composed of a plurality of flat tubes each composed of a first plate and a second plate joined to each other at the periphery so that the internal space communicates with each other. In a heat exchanger that is laminated and integrated, the second fluid flows through the space inside each tube, and the first fluid flows through the gap between adjacent tubes.
In order to form the gap between the adjacent tubes, a large number of embosses projecting toward the cover plate swell in each of the first plates positioned relatively to the cover plate in each tube. The tip of this emboss is in contact with the flat surface of the second plate in the adjacent tube,
The tip of the emboss of the first plate of the tube at the last stage is in contact with the cover plate,
In the second plate of the first stage tube, a large number of embosses projecting toward the bottom surface side of the casing are bulged, and the tip of the emboss is in contact with the bottom surface,
A heat exchanger characterized in that a contact portion at the tip of each emboss is joined by brazing.   The heat exchanger according to claim 1, wherein each of the embosses has a truncated cone shape.   The first plate has the same shape in all stages of tubes, and the second plate has the same shape in all stages of tubes other than the first stage. The heat exchanger as described in. A bottomed cylindrical casing having one open end, a cover plate that closes the opening surface of the casing and defines a space through which the first fluid flows together with the casing, and a core accommodated in the space; The core is composed of a plurality of flat tubes each composed of a first plate and a second plate joined to each other at the periphery so that the internal space communicates with each other. In a heat exchanger that is laminated and integrated, the second fluid flows through the space inside each tube, and the first fluid flows through the gap between adjacent tubes.
In order to form the gap between the adjacent tubes, a large number of embosses projecting toward the cover plate swell in each of the first plates positioned relatively to the cover plate in each tube. The tip of this emboss is in contact with the flat surface of the second plate in the adjacent tube,
The tip of the emboss of the first plate of the tube at the last stage is in contact with the cover plate,
Furthermore, a large number of embosses projecting toward the cover plate are bulged and formed on the bottom wall of the casing, and the tips of the embosses are in contact with the flat surface of the second plate of the first stage tube,
A heat exchanger characterized in that a contact portion at the tip of each emboss is joined by brazing.

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