JP2008128600A - Fin structure, its manufacturing method, and heat transfer tube using the fin structure - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide fin structure, and a heat transfer tube for a heat exchanger using the fin structure capable of providing superior cooling efficiency by promoting an efficient heat exchanging. <P>SOLUTION: In the fin structure, by linearly folding up with respect to a rectangular metal sheet by a portion equivalent to a predetermined height with predetermined intervals, two of the sheets are joined on surfaces of the metal sheets, and plural linear edges are formed with the predetermined intervals with the predetermined height. The heat transfer tube is composed by attaching the fin structure on an inner side or an outer side of the tube, or both. <P>COPYRIGHT: (C)2008,JPO&INPIT

Description

  The present invention relates to a fin structure for fluid agitation in a heat exchanger, and more specifically, to a fluid composed of a cooling medium or a cooling medium that is built in a heat transfer tube in a heat exchange type cooling device and flows through the heat transfer tube. On the other hand, excellent heat is generated by agitating the turbulent flow and vortex, increasing the contact between the heat transfer tube wall surface and the fluid, and effectively separating the laminar flow of the fluid flowing through the heat transfer tube. The present invention relates to a fin structure, a method for manufacturing the fin structure, and a heat transfer tube using the fin structure, in which exchange performance is obtained.

  In recent years, heat exchangers for various forms of fluids such as liquid-liquid, liquid-gas, gas-gas, etc. such as EGR cooler for automobile exhaust gas recirculation, exhaust gas cooler, fuel cooler, oil cooler, intercooler, etc. However, in the heat transfer tubes through which these fluids flow, various devices have been made in order to efficiently radiate or absorb the heat held by the fluids. For example, a method of taking a part of exhaust gas from the exhaust system of a diesel engine, returning it to the intake system of the engine again, and adding it to the air-fuel mixture is called EGR (Exhaust Gas Recirculation) and is called NOx (nitrogen oxide) ), Reducing pump loss, reducing heat dissipation loss to the coolant due to lowering of combustion gas temperature, increasing specific heat ratio due to working gas volume / composition change, and accompanying improvement in cycle efficiency Therefore, it is widely adopted as an effective method for purifying exhaust gas from diesel engines and improving thermal efficiency.

  However, if the temperature of the EGR gas rises and the amount of EGR gas increases, the durability of the EGR valve deteriorates due to its thermal action, and there is a risk of early breakage. There is a need for a structure, and as the intake air temperature rises, the charging efficiency is lowered and the fuel consumption is lowered. In order to avoid such a situation, a device for cooling EGR gas with engine coolant, car air-conditioner refrigerant or cooling air is used, and in particular, gas-liquid that cools EGR gas, which is a gas, with engine coolant. Many heat exchange type EGR gas cooling devices have been proposed, and as means for improving the heat exchange performance, various forms of fins are provided in the pipe through which the EGR gas flows. Among these gas-liquid heat exchange type EGR gas cooling devices, there is still a strong demand for double-tube heat exchange type EGR gas cooling devices that have a simple structure and can be easily installed even in narrow installation spaces. For example, in an exchanger that arranges an outer tube through which liquid passes outside the inner tube through which high-temperature EGR gas passes and performs heat exchange between the gas and the liquid, a metal corrugated plate is inserted as a fin in the inner tube 2 A double-pipe heat exchanger (see, for example, Patent Document 1), an inner pipe through which a medium to be cooled is circulated, an outer pipe provided so as to surround and surround the outer circumference of the inner pipe, and the inner pipe A number of double-pipe heat exchangers have been proposed, including a double-pipe heat exchanger (see, for example, Patent Document 2) that is composed of heat dissipating fins having a thermal stress relaxation function disposed inside. ing.

According to the double-pipe heat exchanger having the fin structure with various improvements as described above, although its structure is simple and compact, excellent cooling efficiency can be expected. Therefore, many heat exchangers for EGR gas cooling that have limited installation space, such as small automobiles, have already been put to practical use, but because of their compact structure, the absolute amount of fluid that flows is naturally There was an unresolved problem that there was a limit and as a result the total heat exchange amount was insufficient.
In order to solve such problems, even if the structure is somewhat complicated and the size must be increased, so-called shell-and-tube multi-tubular heat exchangers must be adopted, and many of these heat exchangers are also used. There are proposals and various improvements have been made.
As an example of a shell-and-tube type multi-tube heat exchanger, a nozzle serving as a cooling water inlet and a cooling water outlet at one end of the outer peripheral portion of the shell main body constituting the cooling jacket are respectively attached to the shell. A bonnet for introducing high-temperature EGR gas is integrally provided at one end in the longitudinal direction of the main body, and a heat-exchanged EGR gas discharging bonnet is integrally provided at the other end via tube sheets attached to the inside of each bonnet. A plurality of flat heat transfer tubes are attached at intervals, and hot EGR gas flows through the flat heat transfer tubes so as to intersect with the cooling water flowing through the shell body, and In addition to the wide heat transfer area formed by the flat heat transfer tube, as shown in an enlarged view of the main part in FIG. A multi-tubular heat exchanger (for example, an excellent heat exchange efficiency can be obtained by increasing the heat transfer area at the same time as reducing the flow of the EGR gas flowing through the interior of the heat sink 40) Patent Document 3) is disclosed.

As another example of the shell-and-tube multi-tube heat exchanger, as shown in FIG. 11, a cooling water inlet C1-a and an outlet C2-b are respectively provided at both ends of the shell body 20a, and the shell body A plurality of flat tubes 23a-1 are stacked inside 20b, and the high-temperature EGR gas flowing through the flow path inside the flat tubes 23a-1 is subjected to heat exchange via the tube wall of the flat tubes 23a-1. In the multi-tube type EGR cooler, the structure of the flat tube 23a-1 is composed of a first plate 23a-1a and a second plate 23a-1b as shown in FIG. An inner fin 26a having a rectangular cross section in the longitudinal direction is provided, and the inner fin 26a of the first plate 23a-1a and the second plate 23a-1b is provided in the inner fin 26a. A portion corresponding to the corrugated ridge line 26a-1 is defined as a turbulent flow forming portion 23a-4, and as shown in FIG. 5C, the turbulent flow forming portion 23a-4 is formed in the concave portion 23a-4a or FIG. As shown, the turbulent flow forming portion 23a-4 is formed with convex portions 23a-4b, and hot EGR gas flowing through the inner peripheral surface of the flat tube 23a-1 and cooling water flowing outside thereof. There has been proposed a heat exchanger (see, for example, Patent Document 4) in which turbulence is generated in both sides to improve heat exchange performance and at the same time, prevention of adhesion of soot of EGR gas in the flat tube 23a-1. .
Japanese Patent Laid-Open No. 11-23181 JP 2000-1111277 A JP 2002-107091 A JP 2004-263616 A

  In each of the above prior arts, in the case of the double-tube type EGR gas cooler disclosed in Patent Documents 1 and 2, by corrugated fins and cross fins, the gas flow is trickled to make contact with the fins. In terms of increasing the area, although some results are expected, the inner surface of the pipe constituting the EGR gas flow path has a smooth inner peripheral surface over the entire length. In many cases, the heat transfer near the center of the pipe becomes insufficient, and the gas flow flows straight along the EGR gas pipe, so that the turbulence of the gas flow becomes insufficient and the boundary layer of the heat transfer surface is sufficient. There is still a problem that the heat transfer performance does not become thin and the heat transfer performance is slightly insufficient, and the compact double pipe structure is bothersome and the absolute amount of exchange heat is insufficient. In multi-tube heat exchangers, the U-shaped plate fins built in the flat tube are formed straight with respect to the gas flow. It could not be said that the flow separation or stirring effect was sufficient.

  On the other hand, in the case of the multi-tube heat exchanger of Patent Document 4, the contact area is increased by making each heat transfer tube in which a plurality of heat transfer tubes are arranged to form a heat transfer tube group into a flat tube. The fin structure as an inner fin installed in the flat heat transfer tube is a corrugated plate fin having a rectangular cross section and a corrugated shape in the longitudinal direction. The flow path is divided into a plurality of small flow paths, and the flow is meandered to increase the heat transfer area, and the corrugated ridge line portion in the fluid flow direction is used as a turbulent flow formation portion, and at the same time, the inner fin Since the upper and lower plates that are not in contact with each other are made to be dotted with convex portions and concave portions as turbulent flow forming portions, initial results are achieved in heat exchange efficiency.

  However, even in the flat heat transfer tube in which the fin structure formed by applying a special plastic processing to a plate material made of a single metal thin plate is used, a small flow formed by the fin structure is used. The pressure loss of the fluid in the channel is unexpectedly low, and the gas or liquid streamline in the channel has the property of flowing down according to its inertia once a laminar flow is generated. Therefore, the heat is not efficiently absorbed from the high-temperature fluid that is the heating element, and the heat is not led to the tip of the fin, resulting in a problem that sufficient heat exchange efficiency cannot be obtained. It was left. That is, even in the fin structure that has been improved to improve the heat exchange efficiency, it does not lead to obtaining sufficient performance as compared to the difficulty in processing and mounting methods such as complicated plastic processing, There were still major issues that were desired to be improved.

  The present invention is intended to solve such problems, and by further improving the fin structure mounted inside and outside the heat exchanger tube for the heat exchanger, the heat exchange is performed despite the simple structure. The present invention provides a fin structure having excellent efficiency, a method for producing the same, and a heat transfer tube for a heat exchanger using the fin structure.

  The fin structure according to the present invention is formed on the surface of the metal thin plate by folding it in a straight line by a predetermined height with a predetermined interval with respect to the rectangular metal thin plate. Basically, two thin plates are combined and a plurality of linear edges are formed at a predetermined height with a predetermined interval, and the deformation corresponds to the height of the linear edges. The fin structure having wave edges whose entire height or any height is formed in a corrugated shape, with a predetermined distance from a rectangular metal sheet, corresponding to a predetermined height in a curved line By folding the sheet as much as possible, two sheets of the thin plate are combined on the surface of the thin metal plate, which corresponds to the height of a plurality of curved edges formed at a predetermined height with a predetermined interval. All parts or any height part has a small pitch waveform A plurality of fin structures having a microwave edge formed, a plurality of portions corresponding to the height of the linear edge, or a plurality of depths at predetermined intervals from the top of the height direction tip to the skirt portion. The gist of the present invention is a fin structure having divided piece-shaped edges formed by providing cuts and alternately bending left and right into arcs from the cut parts.

  In addition, in each edge of the fin structure having the linear or curved edge, the microwave edge, and the divided piece-shaped edge according to the present invention described above, all the portions corresponding to a predetermined height in the edge, or arbitrary The cross section of the height portion is shaped so as to become thinner gradually from the mountain skirt portion toward the top of the tip in the height direction.

  Next, the manufacturing method of the fin structure according to the present invention is a method for producing a linear structure on the surface of a thin metal plate by performing press molding in a constant width or long width direction made of a thin metal plate. Alternatively, the curved cross section has a substantially triangular or flat round shape, and a plurality of edge portions are formed at a predetermined height and at a predetermined interval, and then the two edge portions are overlapped to adhere to each other. After the caulking, the pair of left and right forming rollers are formed so as to gradually become thinner from the crest of the edge portion toward the top in the height direction.

  Further, in the method of manufacturing the fin structure, the edge portion is formed into a corrugated shape by swinging the forming roller to the left and right with a predetermined width when forming with the pair of forming rollers. Is.

  Furthermore, the heat transfer tube according to the present invention includes a fin structure having a linear edge according to the present invention, a fin structure having a wave edge, a fin structure having a microwave edge, and a fin structure having a split piece-shaped edge. It is characterized in that at least one body is attached to the inside or outside of the tube main body or both. The fin structure in the heat transfer tube is preferably attached to the heat transfer tube by welding, brazing, or other joining means.

  Still another heat transfer tube according to the present invention uses two pieces of the fin structure having a predetermined length, and has one end or both ends on the left and right sides of each of the two fin structures. Folded into a circular arc shape, but the two edge portions are alternately butted together, and the edge portions are alternately arranged to form a fluid flow path by joining the end portions on both sides of each fin structure. It is characterized by that.

  In the heat transfer tube according to the present invention, the fin structure having a predetermined length is folded in two, the edge portions are alternately butted and the ends thereof are joined, whereby the edge portions are alternately arranged and the fluid is transferred. The flow path is formed.

  The joining means at the end of the fin structure in the heat transfer tube according to the present invention is appropriately selected from joining means such as welding, brazing and caulking.

The fin structure according to the present invention has a plurality of linear edges or curves formed by joining two thin plates on the surface of one metal thin plate and having a predetermined interval and a predetermined height. Wave edge by forming a part with a curved edge as a basic component and forming all or a part corresponding to the height of this linear edge or curved edge into a corrugated shape with a forming roller Alternatively, a plurality of cuts are provided at predetermined intervals in a microwave edge, all of the portion corresponding to the height of the linear edge, or an arbitrary depth from the top of the height direction tip to the mountain hem portion. , One obtained by dividing the cut portion into a circular arc in opposite directions, and forming a split piece-shaped edge, and the straight or curved edge portion. It is characterized in such that the thickness was molded into a gradually decrease towards the top in the height direction from the foot of the mountain part.
For example, when the fin structure having such a structure is incorporated in a heat exchanger for a high-temperature EGR gas cooling device and is installed in a flat heat transfer tube serving as a fluid flow path of the EGR gas, the fin structure is passed through the heat transfer tube. The EGR gas flow path that is a cooling medium is basically divided by a formed edge portion into a plurality of small flow paths having a rectangular cross section and a free shape in the longitudinal direction, and acts as a so-called plate fin. At this time, the fin structure has a longer edge length and a larger heat transfer area due to the action of the wave edge, the micro wave edge, the split piece edge, and the edge whose top portion is thinner than the skirt portion. The heat transfer is effectively promoted and excellent heat exchange performance is exhibited, and the fluid flowing through the flow path is separated and turbulent in all the laminar flow, and is sufficiently stirred so that the wall surface of the heat transfer tube Contact with Repeatedly, it is efficiently heat transfer to the cooling medium flowing through the outer heat exchange performance is further improved.

  Further, the method for manufacturing the fin structure according to the present invention includes a predetermined shape such as a straight line or a curved line in a width direction of a standard or long coil made of a metal thin plate, and a substantially triangular or flat round cross section. At a predetermined height on the surface of the thin metal plate by press-molding at a height and with a predetermined interval, and then adhering the triangular or flat-round edge portions to each other in a stacked manner And forming a plurality of edge portions with a predetermined interval, and further forming the edge portions with a forming roller so that the edge portions gradually become thinner from the crest of the edge portion toward the top of the tip in the height direction. Further, it is a method of making the forming roller a wave edge by swinging left and right with a predetermined width, and since the fin structure can be manufactured only by plastic working, its manufacturing cost is reduced. It can be reduced in width.

  Furthermore, in the heat transfer tube according to the present invention, the edge portions are alternately formed by joining the left and right end portions of each of the various fin structure bodies so as to face each other, or by folding the two fin portions and joining the end portions. Since the fluid flow path is formed by the arrangement of the fin, the heat transfer is effectively promoted by the action of the fin structure, and excellent heat exchange performance is exhibited. All laminar flows are peeled off, sufficiently agitated and repeatedly contacted with the wall surface of the heat transfer tube, and heat is efficiently transferred to the cooling medium flowing outside thereof, thereby obtaining excellent heat exchange performance. Therefore, according to the heat transfer tube according to the present invention, the exhaust gas cooler, the EGR gas cooler, the fuel as well as for the multi-tube heat exchanger disposed in the EGR gas recirculation system due to its excellent heat exchange performance. A heat exchanger that can be reduced in size and weight, such as an air cooler, oil cooler, and intercooler, contributes to the compactness of the device, and can be easily installed in a limited space, at a relatively low cost. be able to.

  Hereinafter, embodiments of the present invention will be described in more detail with reference to the accompanying drawings and examples. However, the present invention is not restricted thereby, and design changes can be freely made within the scope of the gist of the present invention. Is possible.

  FIG. 1 shows a fin structure according to a first embodiment of the present invention. FIG. 1 (a) is a perspective view schematically showing a main part of a fin structure in which an edge portion is formed linearly, and FIG. FIG. 2A is an enlarged front view showing a single edge portion in FIG. 2A, and FIG. 2 shows a fin structure (fin structure having a wave edge) according to a second embodiment of the present invention and its manufacturing procedure. (A) is a principal part perspective view which shows typically the wave edge shaping | molding processing state by the forming roller with respect to the said linear edge part, (d) is a front view which shows typically a wave edge single-piece | unit, (e) is the wave. FIG. 3 is a schematic plan view for explaining the form of a single edge, and FIG. 3 shows a fin structure (fin structure having a microwave edge) according to a third embodiment of the present invention, and its manufacturing procedure, (a) Has a curved edge. The principal part perspective view which shows typically the state performed, (b) is a principal part perspective view which shows typically the micro wave edge shaping | molding processing state by the shaping | molding roller with respect to the curvilinear edge part in the figure (a), (c) ) Is a schematic enlarged front view of the main part for more specifically explaining the micro wave edge molding state in FIG. 4B, FIG. 4D is a front view schematically showing the micro wave edge alone, ) Is a schematic plan view for explaining the form of the single microwave edge, and FIG. 4 is a fin structure (fin structure having divided piece-shaped edges) according to the fourth embodiment of the present invention and its manufacturing procedure. (A) is a principal part perspective view schematically showing a fin structure in which the edge part is formed in a straight line shape, (b) is a principal part enlarged front view showing a single piece of the split piece edge part, c) The main part 5A and 5B show an example of a basic method for manufacturing a fin structure according to the present invention. FIG. 5A is a side view schematically showing a molding apparatus for explaining the example. FIG. Fig. 6 is an enlarged front view schematically showing a single unit of the fin structure formed by the apparatus shown in Fig. 6A, and Fig. 6 is another mold for a press forming apparatus in the manufacturing method of the fin structure shown in Fig. 5. FIG. 7 is a schematic side view showing a forming method, FIG. 7 illustrates a heat transfer tube using a fin structure having a straight edge shown in FIG. 1, and (a) is a fin structure having a straight edge having the same thickness. FIG. 8B is a schematic front view showing an example of a heat transfer tube using the heat transfer tube. FIG. 8B is a schematic front view showing an example of a heat transfer tube using a fin structure having linear edges with different thicknesses shown in FIG. Another example of heat transfer tube using fin structure with thick straight edge (A) is a front view schematically showing the state before the assembly, (b) is a schematic front view showing the assembled heat transfer tube, and FIG. 9 is shown in FIGS. 1 and 2. The heat transfer tube which mounted | wore with the substantially same fin structure was illustrated, (a)-(f) is the principal part which shows an example of the heat transfer tube which mounted this fin structure on the inner side or the outer side, or both It is an enlarged front view.

  The fin structure according to the present invention is basically composed of a rectangular metal thin plate, for example, by using a constant-width or long-length coil as a raw material, and performing press forming, roll forming, or the like in the width direction. Although it is molded, the standard or long coil used as the material is normally selected from austenitic stainless steel such as SUS303, SUS304L, SUS316, SUS316L, etc. with a plate thickness of about 0.05 to 0.5 mm. Adopted.

  The fin structure 1 according to the first embodiment of the present invention shown in FIG. 1 is shown in FIG. 1A in the lateral width direction of the thin plate 1-1 by press-molding a metal thin plate 1-1 as a material. In this way, a vertical straight edge 1-2 is formed with a predetermined interval, and the top 1-2a has a flat round shape with a predetermined height h, and at the same time, the straight edge 1-2. The bottom portion 1-2b of the metal plate 1-1 is closed, and the two thin metal plates 1-1 are overlapped to have a linear edge 1-2 closely adhered to each other.

The fin structure 2 according to the second embodiment of the present invention shown in FIG. 2 is similar to the embodiment shown in FIG. 1 in that the thin plate 2-1 is formed by press-molding the metal thin plate 2-1. A vertical straight edge (see FIG. 1 a) having a predetermined interval in the width direction and having a predetermined height and a cross section of the top portion 2-2 a having a flat round shape is formed. After the bottom 2-2b is closed and the two metal thin plates 2-1 are overlapped to form a linear edge (not shown) that is in close contact with each other, a predetermined angle with respect to the linear edge is previously set. By the pair of left and right forming rollers R1 adjusted, the linear edge formed by overlapping the two sheets is formed so as to gradually become thinner from the mountain hem portion 2-2c toward the top portion 2-2a at the tip in the height direction. At the same time, the forming roller R1 is swung left and right with a predetermined width. The wave having a wave 2-2d that swings to the left and right with a predetermined width from the top 2-2a at the front end of the edge in the height direction to the crest 2-2c by being moved in the length direction. It has an edge 2-2.
That is, the fin structure 2 having the wave edge 2-2 is formed in the wave edge 2-2 in the lateral width direction of the metal thin plate 1 as a material, as schematically shown in FIG. The bottom portion 2-2b and the mountain skirt portion 2-2c are linear, and the wave 2-2d is formed at a predetermined pitch interval from the top portion 2-2a at the tip in the height direction toward the mountain skirt portion 2-2c. is there.

The fin structure 3 according to the third embodiment of the present invention shown in FIG. 3 is formed by press molding a metal thin plate 3-1 as a material in substantially the same process as the embodiment shown in FIGS. 1 and 2. At the same time as forming a vertical curved edge 3-2 in which the cross section of the apex 3-2a is flat with a predetermined height in the horizontal width direction of the thin plate 3-1, the curve The bottom edge 3-2b of the curved edge is closed to form a curved edge 3-2 in which the two metal thin plates 3-1 are stacked and adhered to each other, The pair of left and right forming rollers R2 adjusted to a predetermined angle causes the curved edge 3-2, which is overlapped by two sheets, to gradually rise from the crest portion 3-2c toward the top portion 3-2a at the tip in the height direction. At the same time, the molding roller R2 is formed into the same figure ( ) By moving in the length direction while swinging left and right with a predetermined width w, as shown in FIG. 3, from the top 3-2a at the tip of the edge in the height direction to the crest portion 3-2c, A curved microwave 3-2d that swings left and right with a predetermined width is formed. A gear roller may be used as the forming roller R2.
That is, the fin structure 3 having the curved edge 3-2 having the microwave 3-2d is curved in the lateral width direction of the metal thin plate 1 as a material, as shown in FIGS. The bottom portion 3-2c of the curved edge 3-2 is curved, and a microwave 3-2d is formed that swings to the left and right at a predetermined pitch interval from the top portion 3-2a at the tip in the height direction toward the mountain bottom portion 3-2c. It has been done.

The fin structure 4 according to the fourth embodiment of the present invention shown in FIG. 4 has a predetermined interval in the width direction of the thin plate 4-1 by press forming on the metal thin plate 4-1 as a material, as described above. And at the same time forming a vertical straight edge 4-2 having a flat cross section at the top 4-2a with a predetermined height, and simultaneously closing the bottom 4-2b of the straight edge, After the two metal thin plates 4-1 are stacked to form a linear edge 4-2 in close contact with each other, the linear edge is adjusted to a predetermined angle similar to that shown in FIG. By the pair of left and right forming rollers (not shown), the two straight edges are gradually thinned from the crest 4-2c toward the top 4-2a at the tip in the height direction. Forming while moving the forming roller, then the linear shape A plurality of cuts 4-2d at a predetermined interval from the entire portion corresponding to the height of the wedge 4-2 or an arbitrary depth from the apex portion 4-2a at the tip in the height direction toward the mountain skirt portion 4-2c. And by dividing the edge 4-2 alternately left and right in the arc shape from the notch 4-2d portion, it has divided piece-shaped edges 4-2e having a predetermined width that are alternately bent left and right in the arc shape. ing.
The width of the divided piece-shaped edge 4-2e of the fin structure 4 having the divided piece-shaped edge 4-2e depends on the size of the fin structure 4, the size of the heat transfer tube using the fin structure 4, and the like. In addition, if necessary, the divided piece-shaped edge 4-2e itself may be further cut to form a similar small divided piece-shaped edge. The plurality of cuts 4-2d may be processed before the bending process by press molding or before the molding process by the molding roller.

Next, the manufacturing method of the fin structure which concerns on this invention is demonstrated based on FIG. 5, FIG.
For example, the cross-sectional shape shown in FIG. 5A is triangular with respect to a metal thin plate 5-1 (hereinafter, abbreviated as “thin plate” for convenience of explanation) having a long coil made of SUS304L austenitic stainless steel and having a predetermined width. A male mold (lower mold) 6-1 having a linear chevron convex surface adjusted to a predetermined height, and a female having a triangular concave section corresponding to the male mold 6-1. A substantially triangular edge portion 5-2 is formed by performing press molding at a predetermined interval in the width direction of the thin plate 5-1 by a press molding machine 6 equipped with a mold (upper mold) 6-2. Then, the edge portion 5-2 is subjected to pressure contact processing, and the mountain skirt portion 5-2b is closed so as to adhere to each other as a two-layer stack, and is almost perpendicular to the surface lateral width direction of the thin plate 5-1. At a given height at an angle and for a given time A plurality of edge portions 5-2 are formed, and the edge portions 5-2 are further moved onto a guide 7 having a substantially right-angled corner 7-1, and the bottom portion 5-2c is moved to the corner of the guide 7. The edge portion 5-2 that protrudes on the corner 7-1 is bent from both sides by a pair of left and right forming rollers R3 adjusted to a predetermined angle. A thin metal plate is formed by forming so that the plate thickness gradually decreases from the crest 5-2b of the edge portion 5-2 toward the top portion 5-2a at the tip in the height direction. The fin structure 5 in which a plurality of linear edge portions 5-2 are formed on the surface can be obtained.

  The cross-sectional shape of the obtained fin structure 5 is an enlarged view of FIG. 5 (b), in which the two thin plates 5-1 are stacked on the thickness t of the thin plate 5-1. The thickness of the mountain skirt portion 5-2b is 2t, and it is desirable that the top portion 5-2a be formed and processed so as to have the same thickness t to 0.5t. In addition, although the elongation corresponding to the thinning to 0.5t-1t arises in the top part 5-2a of this fin structure 5 by the shaping | molding process in this case, this elongation becomes distortion as it is and becomes an irregular waveform. In this molding process, the pair of left and right molding rollers R3 are swung left and right with a predetermined width w as shown in FIG. A wave having a constant wave width (wave) can be formed at a pitch interval of 5 mm, and this wave can be regularly formed at the apex portion 5-2a at the tip of the fin structure 5 in the height direction. Become.

  The fin structure 5 was press-molded by attaching the molds 6-1 and 6-2 having a triangular cross section to the press molding machine 6 for forming the edge portion 5-2. Instead of the mold, as shown in FIG. 6, a male mold (lower mold) 6 a-1 having a flat circular shape in cross-sectional shape and adjusted to a predetermined height, and the male mold 6 a- Corresponding to 1, a female mold (upper mold) 6a-2 having a flat round concave surface is mounted and press-molded. Thereafter, the fin structure can be obtained by the same procedure as described above. Note that the edge portion 3-2 formed on the surface of the thin plate 3-1 as shown in FIG. 3 is obtained by replacing the pair of dies with a die having corrugated irregularities at a predetermined pitch in advance during press molding. However, the shape of the fin structure 3 in this case may be a fin structure as shown in FIGS. 3 (a) to 3 (e). Not only the top part 3-2a of the body 3 but also the crest part 3-2c thereof is formed into a waveform at a predetermined pitch interval.

The fin structure according to the present invention formed as described above can constitute the various heat transfer tubes 10 to 18 illustrated in FIGS.
First, the heat transfer tubes 10 and 11 shown in FIG. 7 are configured using the same fin structure 1 having a linear edge as shown in FIG. 1, and the heat transfer tube 10 shown in FIG. The two fin structures 10-1 having straight edges 10-2 having the same thickness are overlapped so that the straight edges 10-2 are alternately arranged, and the left and right end portions 10-3 are overlapped. By joining, a plurality of fluid flow paths 10-4 are formed by the straight edges 10-2 of the two fin structures 10-1.
Further, the heat transfer tube 11 shown in FIG. 2B has a straight edge 11-2 formed so that its plate thickness gradually decreases from the crest portion of the edge portion toward the top of the tip in the height direction. The two fin structures 11-1 are stacked by overlapping the fin structures 11-1 so that the respective linear edges 11-2 are alternately arranged, and joining the left and right ends 11-3 thereof. A plurality of fluid flow paths 10-4 are formed by the straight edges 11-2. In addition, the top part of an edge may contact | abut with the non-edge part of the fin structure which opposes, and the applicable contact part may be joined.

  The heat transfer tube 12 shown in FIG. 8 is configured by using one fin structure 12-1 having a straight edge 12-2 having the same thickness, and the interval between the straight edges 12-2 is substantially at the center. The fin structure 12-1 having a predetermined length and a large length is used, and the fin structure 12-1 is folded inward at approximately the center so that the linear edges 12-2 are alternately arranged. A plurality of fluid flow paths 12-4 are formed by the linear edges 12-2 by joining both end portions 12-3. In addition, the top part of an edge may contact | abut with the non-edge part of the fin structure which opposes, and the applicable contact part may be joined.

  In addition, when joining the end portions of the fin structure 12-1 in the heat transfer tubes 10, 11, and 12 shown in FIGS. 7 and 8, they are joined in a state of maintaining airtightness with a predetermined pressure resistance. In general, it is desirable to join by welding, brazing, caulking or the like alone or in combination. Moreover, you may braze the joining part of each edge mutually.

Furthermore, the heat transfer tubes 13 to 18 shown in FIG. 9 are configured by mounting various fin structures on the inside or the outside of the heat transfer tubes or both, and the heat transfer tubes 13 shown in FIGS. 16 to 16 show the fin structure inside the tube, the heat transfer tube 17 shown in FIG. 8E shows the fin structure outside the tube, and the heat transfer tube 18 shown in FIG. It is configured to be worn on both the inside and outside of the body.
That is, the heat transfer tube 13 shown in FIG. 9A has a tubular structure in which a fin structure 13a having substantially the same linear edge 13a-1 as the fin structure shown in FIG. 1 is bent inward. The heat transfer tube 14 attached to the inner peripheral surface of the tube 13-1, shown in FIG. 5B, is a flat heat transfer tube such that the fin structures 14a having the wave edges 14a-1 are opposed to each other. The heat transfer tube 15 shown in FIG. 14 (c), which is internally fixed to 14-1, is provided in the flat heat transfer tube 15-1 by alternately shifting the positions of the edges of the fin structure 15a having the wave edge 15a-1. The fixed one, the heat transfer tube 16 shown in FIG. 2D, has the fin structure 16a having the wave edge 16a-1 internally fixed to the flat heat transfer tube 16-1 having the same thickness as the fin structure 16a. Thing, figure ( The heat transfer tube 17 shown in FIG. 4 is a tube structure 17a having a fin structure 17a having a wave edge 17a-1 attached to the outer peripheral surface of the tube 17-1, and the heat transfer tube 18 shown in FIG. 1 shows a state in which a fin structure 18a having a wave edge 18a-1 is mounted on the inner peripheral surface and the outer peripheral surface of FIG. The fin and the pipe are preferably joined by brazing or welding.

  In the various heat transfer tubes of the present invention described above, efficient heat transfer is promoted by the fin structure incorporated therein, and the laminar flow such as EGR gas flowing through the tube is effectively separated and stirred. Excellent heat exchange performance can be obtained. Furthermore, in the case of the heat transfer tube having the fin structure mounted on both the inner peripheral surface and the outer peripheral surface of the tube, the heat dissipating action of the fin structure on the outer peripheral surface is also added, so that more excellent heat exchange performance can be obtained.

  According to the above fin structure according to the present invention, it is attached to the inner peripheral surface or the outer peripheral surface of various heat transfer tubes including flat tubes, or both, or the fin structure itself forms a heat transfer tube independently, The flow path of the fluid to be cooled or flowing through the inside and outside of the heat transfer tube is divided into a plurality of small flow paths having a substantially rectangular cross section and a free shape in the longitudinal direction, and at the same time, the tip of the fin structure The heat transfer through the tip of the fin is efficiently promoted, and the laminar flow is separated from the fluid flowing through the flow path. The heat exchanging performance inside and outside the heat transfer tube is further improved.

  Furthermore, the fin structure according to the present invention can be manufactured easily and efficiently by two-stage processing means by press forming and rolling on a single metal thin plate, greatly increasing the manufacturing cost. In addition, the heat exchange performance of the heat transfer tubes equipped with the fin structure obtained in addition is extremely excellent. In particular, it is suitable for heat exchangers for exhaust heat recovery from exhaust gas, EGR gas coolers, fuel coolers and oil coolers, and heat exchanger tubes for intercoolers, etc. Heat transfer tubes and multi-tube heat exchangers incorporating the heat transfer tubes enable their devices to be smaller and lighter due to their excellent heat exchange performance, contributing to the compactness of the devices Te, the heat exchanger can be easily installed in a limited space, it is possible to provide a relatively low cost, expected spread in a wide range of applications in the art.

The fin structure which concerns on 1st Example of this invention is shown, (a) is a principal part perspective view which shows typically the fin structure in which the edge part was shape | molded linearly, (b) is the figure ( It is a front view which expands and shows the simple substance of the edge part in a). The fin structure (fin structure which has a wave edge) which concerns on 2nd Example of this invention, and its manufacturing procedure are shown, (a) is a wave edge shaping | molding process state with the shaping | molding roller with respect to the said linear edge part. (D) is a front view schematically showing a single wave edge, and (c) is a schematic plan view for explaining the form of the single wave edge. The fin structure (fin structure which has a microwave edge) which concerns on 3rd Example of this invention, and its manufacturing procedure are shown, (a) is the principal part which shows typically the state by which the edge part was shape | molded in curve shape. A perspective view, (b) is a principal part perspective view which shows typically the micro wave edge shaping | molding state by the shaping | molding roller with respect to the curvilinear edge part in the figure (a), (c) is the micro wave in the figure (b). In order to more specifically explain the state of edge forming, a schematic enlarged front view of the main part, (d) is a front view schematically showing the microwave edge unit, and (e) is a form of the microwave edge unit. It is a typical top view for demonstrating. The fin structure (fin structure which has a division | segmentation piece shape edge) which concerns on 4th Example of this invention, and its manufacturing procedure are shown, (a) is a fin structure with which the edge part was shape | molded linearly typically. The principal part perspective view shown, (b) is the principal part expansion front view which shows the single-piece | unit of the division | segmentation piece shape edge part, (c) is the principal part perspective view. An example of the manufacturing method of the basic fin structure which concerns on this invention is shown, (a) is a side view which shows typically the shaping | molding apparatus for demonstrating the example, (b) is the figure (a) It is an enlarged front view which shows typically the single-piece | unit of the fin structure shape | molded by the apparatus shown in FIG. It is a schematic side view which shows the shaping | molding method by the metal mold | die for another press molding apparatus in the manufacturing method of the fin structure shown in FIG. FIG. 1 illustrates a heat transfer tube using a fin structure having a straight edge shown in FIG. 1, and (a) is a schematic front view illustrating an example of a heat transfer tube using a fin structure having a straight edge having the same thickness. FIG. 6B is a schematic front view showing an example of a heat transfer tube using a fin structure having linear edges with different thicknesses shown in FIG. The other example of the heat exchanger tube using the fin structure which has the straight edge of the same thickness is shown, (a) is a front view which shows the state before the assembly typically, (b) is an assembly. It is a schematic front view which shows the heat exchanger tube. FIGS. 1 and 2 illustrate a heat transfer tube equipped with a fin structure substantially similar to that shown in FIGS. 1 and 2, wherein (a) to (f) are attached to the inside or outside of the tube or both. It is a principal part enlarged front view which shows an example of the made heat exchanger tube. It is a principal part enlarged front view of the heat exchanger tube which equipped the conventional fin structure. An example of a conventional multi-tube heat exchanger is shown, (a) is a partially broken perspective view of the multi-tube heat exchanger, and (b) a flat heat transfer tube alone installed in the multi-tube heat exchanger. An exploded perspective view, (c) is a cross-sectional view of a single flat heat transfer tube, and (d) is a cross-sectional view of another flat heat transfer tube.

Explanation of symbols

DESCRIPTION OF SYMBOLS 1, 5 Fin structure 1-12, 3-1, 4-1, 5-1 Metal thin plate 1-2 Straight edge 2 Fin structure 2-2 which has a wave edge Wave edge 2-2d Wave 3 Fin structure with micro wave edge 3-2 Curved edge 3-2d Micro wave 4 Fin structure with split piece edge 4-2 Straight edge 4-2e Split piece edge 5 -2 Edge part 6 Press molding machine 6-1 Male mold 6-2 Female mold 7 Guide 10-18 Heat transfer tube 10-1 to 18-1 Fin structure 10-4 to 12-4 Fluid flow path 13-1, 17 -1 Tubes 14-1, 15-1, 16-1, 18-1 Flat heat transfer tubes 10-2, 11-2, 12-2, 13a-1 Linear edges 13a-18a Fin structures 14a-1 18a-1 Wave edge R1-R3 Forming roller

Claims (12)

  By folding the rectangular metal thin plate in a straight line by a predetermined height with a predetermined interval, the two thin plates are combined on the surface of the metal thin plate. A fin structure in which a plurality of linear edges are formed with a predetermined height and a predetermined height.   By folding the rectangular metal thin plate in a straight line by a predetermined height with a predetermined interval, the two thin plates are combined on the surface of the metal thin plate. A fin structure having a wave edge in which all or a portion corresponding to the height of a plurality of linear edges formed at a predetermined height with a predetermined interval is formed into a waveform.   By folding the rectangular metal thin plate at a predetermined interval and by an amount corresponding to a predetermined height, the two thin plates are combined on the surface of the metal thin plate. All of the portions corresponding to the heights of the plurality of curved edges formed at a predetermined height and at a predetermined height, or any height portion has a microwave edge formed into a small pitch waveform Fin structure.   By folding the rectangular metal thin plate in a straight line by a predetermined height with a predetermined interval, the two thin plates are combined on the surface of the metal thin plate. At a predetermined depth to all of the portions corresponding to the heights of a plurality of linear edges formed at a predetermined height and at an arbitrary depth from the top of the height direction tip to the skirt portion. The fin structure which has the division | segmentation piece-shaped edge formed by providing several notches in the space | interval, and bend | folding in the circular arc shape from the said notch part alternately right and left.   In the straight or curved edge formed by combining two metal thin plates, all of a portion corresponding to a predetermined height at the edge, or a cross section of an arbitrary height portion is height from the mountain skirt portion. The fin structure according to any one of claims 1 to 4, wherein the fin structure is formed so as to be gradually thinner toward a top portion of a direction tip.   The surface of the metal thin plate is formed in a straight or curved shape by pressing in the width direction of a constant width or long coil made of a metal thin plate, and the cross-section is substantially triangular or flat round. After forming a plurality of edge portions at a predetermined height and with a predetermined interval, the two edge portions are overlapped and adhered to each other, and then the edge portions are formed with a pair of left and right forming rollers. A method for manufacturing a fin structure, wherein the fin structure is formed so as to be gradually thinner from a mountain skirt portion toward a top portion in a height direction.   The fin structure according to claim 6, wherein the edge portion is formed into a corrugated shape by swinging the forming roller left and right with a predetermined width when forming with the pair of forming rollers. Method.   At least one of the fin structure in which the straight edge is formed, the fin structure having a wave edge, the fin structure having a micro wave edge, and the fin structure having a divided piece-shaped edge is arranged inside or outside of the pipe or its A heat transfer tube mounted on both sides.   The heat transfer tube according to claim 8, wherein the fin structure is attached to the heat transfer tube by welding, brazing, or other joining means.   Two pieces of the fin structure having a predetermined length are used, and one or both ends of the two fin structures are bent in an arc shape on both the left and right sides of each of the two fin structures. A heat transfer tube in which the edge portions are alternately abutted and end portions on both sides of each fin structure are joined to form the fluid flow path by alternately arranging the edge portions.   A heat transfer tube in which the edge portions are alternately arranged by joining the end portions by alternately folding the fin structure having a predetermined length into two, thereby forming a fluid flow path.   The heat transfer tube according to claim 10 or 11, wherein a joining means at an end portion of the fin structure is appropriately selected from joining means such as welding, brazing, and caulking.

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