Plate fins

Abstract

To provide a plate fin capable of ensuring strength even when made of a soft metal. [Solution] The plate fin 1 comprises a heat sink 10, a through hole 11, a raised portion 12, and a step portion 20. The through hole 11 provided in the heat sink 10 comprises, at its base, a peripheral protruding portion 11a that protrudes slightly in the penetration direction of the heat transfer tube, and a through hole main body 11b that protrudes further from the peripheral protruding portion 11a. The raised portion 12 provided in the heat sink 10 protrudes in the opposite direction to the protruding direction of the through hole 11. The step portion 20 provided in the heat sink 10 protrudes slightly in the vicinity of two opposing sides of the heat sink 10 in the opposite direction to the protruding direction of the through hole 11 more than other regions. By adopting such a shape, the heat sink has improved resistance to twisting, bending, etc., and can ensure strength even when made of a soft metal.

Description

[Technical field]

[0001] The present invention relates to a plate fin for use in a heat exchanger or the like. [Background technology]

[0002] Conventionally, an example of a heat exchanger equipped with this type of plate fin is described in Patent Document 1. This plate fin is a heat exchanger fin comprising a heat sink plate and a plurality of heat transfer tube openings, four or more of which are formed and arranged in two or more rows for the heat transfer tubes penetrating the heat sink plate, and the plurality of heat sink plates are surrounded between four adjacent heat transfer tube openings among the plurality of heat transfer tube openings, and have linear protrusions formed in a front view on the portion facing the heat transfer tube. With this configuration, a protrusion that is linear when viewed from the front is formed in the portion facing the heat transfer tube, and the air flowing in the space between the opening hole for the heat transfer tube and the protrusion flows in a direction different from the air flow direction, thereby forming a turbulent region between the opening hole for the heat transfer tube and the protrusion.

[0003] Furthermore, Patent Document 2 discloses a plate fin that includes a heat sink plate, a through hole, a deformation portion, a large diameter region, and a small diameter region. This through hole is for passing a heat transfer tube through it, and the deformed portion is formed by extruding and deforming the periphery of the through hole from the back side to the front side of the heat sink plate, and the large diameter region extends from the periphery of the through hole at a predetermined first angle inclined toward the inside of the through hole with respect to the penetration direction of the through hole, and the small diameter region extends from the periphery of the large diameter region at a predetermined second angle inclined toward the inside of the through hole with respect to the penetration direction of the through hole that is smaller than the first angle. [Prior art documents] [Patent documents]

[0004] [Patent Document 1] Patent Publication No. 2022-87576 [Patent Document 2] Utility Model Registration No. 3239049 Summary of the Invention [Problem to be solved by the invention]

[0005] However, if the heat sink plates of the plate fins, which were previously made of stainless steel, are made of aluminum or an aluminum alloy (hereinafter referred to as aluminum alloy) in order to reduce the material costs and processing costs of such plate fins and the heat exchangers constructed using them, the aluminum or aluminum alloy has a relatively low strength compared to stainless steel and is difficult to maintain its strength, resulting in a problem of increased maintenance costs in the long term.

[0006] The present invention has been made to solve the above-mentioned problems, and aims to provide a plate fin that can ensure strength without increasing long-term maintenance costs, even when the heat sink is made of a relatively soft metal such as aluminum or an aluminum alloy. [Means for solving the problem]

[0007] The plate fin of the present invention comprises a heat sink plate having a plurality of through holes for passing heat transfer tubes therethrough, the plurality of through holes being arranged adjacent to one another on the heat sink plate to form a plurality of through hole rows, and between each of the plurality of through hole rows a row of raised portions being arranged adjacent to one another is provided, and each through hole in the through hole row has a periphery protruding from one main surface side of the heat sink plate toward the other main surface side, and each raised portion in the raised portion row protrudes from the other main surface side of the heat sink plate toward one main surface side. As a result, the multiple rows of ridges and peripheral protrusions formed on the heat sink plate prevent the heat sink plate from deforming even when an external force is applied to the heat sink plate, making it possible for the heat sink plate to maintain its strength and hold the heat transfer tube even if it is made of a metal with low strength.

[0008] The plate fin of the present invention is configured so that each through hole in the row of through holes has a flat peripheral protrusion on its periphery that protrudes with a step that rises from one main surface side of the heat sink to the other main surface side, and a through hole main body that protrudes from the peripheral protrusion toward the other main surface side with its inner diameter becoming smaller. Therefore, the peripheral protrusion reduces the external force transmitted from the heat transfer tube via the through hole main body that is in direct contact with the heat transfer tube, and transmits the force to the heat sink, thereby reinforcing the through hole itself and, ultimately, the heat sink.

[0009] The plate fin according to the present invention is configured so that the heat sink plate has a step portion on its periphery that rises from one main surface side to the other main surface side, or from the other main surface side to the one main surface side. Therefore, the step portion can reduce the external force transmitted to the heat sink and reinforce the heat sink.

[0010] The plate fins according to the present invention are configured so that the heat sink is made of aluminum or an aluminum alloy. Even in this configuration, the strength of the heat sink is ensured, which is preferable for the present invention. Effect of the Invention

[0011] According to the present invention, it is possible to provide plate fins that can ensure the strength of the heat sink even if it is made of a soft metal such as aluminum or an aluminum alloy, and that can maintain their strength without increasing long-term maintenance costs. [Brief description of the drawings]

[0012] [Figure 1] FIG. 2 is a plan view of the plate fin according to the present invention. [Diagram 2] 1A is a cross-sectional view of the plate fin of the present invention taken along line AA, FIG. 1B is a cross-sectional view of the plate fin of the present invention taken along line BB, FIG. 1C is a cross-sectional view of the plate fin of the present invention taken along line CC, and FIG. 1D is a cross-sectional view of the plate fin of the present invention taken along line DD. [Diagram 3] 4 is a diagram showing the protruding direction of the through hole of the plate fin of the present invention and the angle formed by the outer protruding portion and the inner protruding portion. FIG. [Figure 4] 1A is a cross-sectional view showing the steps for manufacturing a heat exchanger using the plate fins of the present invention; FIG. 1B is a cross-sectional view showing the steps for manufacturing a heat exchanger using the plate fins of the present invention; FIG. 1C is a partially cut-away cross-sectional view showing the steps for manufacturing a heat exchanger using the plate fins of the present invention; and FIG. 1D is a partially cut-away cross-sectional view showing the steps for manufacturing a heat exchanger using the plate fins of the present invention. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0013] Hereinafter, an embodiment of the present invention will be described with reference to the drawings.

[0014] 1. Plate fin shape As shown in Figure 1, the plate fin 1 of the present invention comprises a rectangular heat sink 10, a plurality of through hole rows 11A each consisting of a plurality of through holes 11 formed in the heat sink 10, a plurality of raised portion rows 12A each consisting of a plurality of raised portions 12 formed between the through hole rows 11A, and a pair of step portions 20 formed along the peripheral edges of the opposing long sides of the heat sink 10.

[0015] The heat sink 10 is a rectangular plate having one main surface 10a and the other main surface 10b. The heat sink 10 is preferably made of, for example, aluminum or an aluminum alloy.

[0016] 4, the through holes 11 are for passing the heat transfer tubes H through. The through holes 11 are formed so that their centers coincide with the lattice points on the heat sink 10. The heat sink 10 is provided with a plurality of through hole rows 11A arranged adjacent to each other. The periphery of the through hole 11 has a flat peripheral protrusion 11a that protrudes from one main surface 10a of the heat sink 10 toward the other main surface 10b of the heat sink 10 to have a step. The peripheral protrusion 11a of the through hole 11 protrudes from one main surface 10a of the heat sink 10 toward the other main surface 10b of the heat sink 10. As a result, the periphery of the through hole 11 protrudes slightly higher in the protruding direction of the through hole 11. The periphery of the through hole 11 is formed, for example, by extrusion deformation. Furthermore, a through hole main body 11b is provided from the center of the peripheral protruding portion 11a, protruding further in the protruding direction of the through hole 11.

[0017] The through hole body 11b protrudes from the peripheral protrusion 11a toward the other main surface 10b with its inner diameter becoming smaller. The through hole body 11b includes an outer protrusion 11b1 on the peripheral protrusion 11a side and an inner protrusion 11b2 on the tip side. As shown in Fig. 3, the outer protrusion 11b1 protrudes substantially perpendicularly from the through hole 11 in the protruding direction of the through hole 11. The inner protrusion 11b2 protrudes at a predetermined angle α toward the inside of the through hole 11 from the protruding direction of the through hole 11.

[0018] The raised portion 12 is formed into a plurality of raised portion rows 12A in which a plurality of raised portions 12 are arranged adjacent to one another. Each raised portion 12 protrudes from the other main surface 10b side toward one main surface 10a side of the heat sink 10. The raised portions 12 are formed to protrude between four through holes 11 whose centers are located at four lattice points (those closest to each other) so that their longitudinal direction forms an approximately semi-cylindrical surface along the longitudinal direction of the heat sink 10 and both ends form approximately quarter-spheres.

[0019] The step portions 20 are provided along and near two opposing long sides of the heat sink 10. The step portions 20 are raised from one main surface 10a side toward the other main surface 10b side at the periphery of the heat sink 10. Due to the step portions 20, the heat sink 10 is raised slightly higher in the vicinity of the pair of long sides toward the protruding direction of the through holes 11 than the other regions. Note that the step portions 20 may be raised from the other main surface 10b side toward the one main surface 10a side at the periphery of the heat sink 10.

[0020] 2. Manufacturing of plate fins A plate fin having such a shape can be manufactured, for example, as follows. (i) Press processing First, an aluminum plate or an aluminum alloy plate to be used as a heat sink is set in a press. Next, dies (upper and lower dies) with shapes corresponding to the through holes, steps, and raised portions are attached to a press. The press is operated and an aluminum or aluminum alloy sheet is sandwiched between the upper and lower dies, thereby simultaneously forming the through holes, steps, and protrusions to obtain the plate fins. (ii) Machining First, an aluminum plate or an aluminum alloy plate is fixed to a machine tool such as a milling machine or a machining center. Next, a cutting tool is used to cut out the through holes, the steps, and the raised portions. (iii) Sheet metal processing The aluminum or aluminum alloy plate is bent and welded to form the through holes, steps, and protrusions. (iv) Casting Aluminum or an aluminum alloy is melted and poured into a mold to form the through holes, steps, and raised portions.

[0021] 3. Manufacturing of heat exchangers The heat exchanger can be manufactured as follows using the plate fins prepared according to any one of (i) to (iv) and heat transfer tubes. Specifically, a heat exchanger constructed using the plate fins of the present invention comprises at least two plate fins 1 and a heat transfer tube H, and the two plate fins 1 are stacked on top of each other so that the inner protrusion 11b2 of the through hole 11 of the lower plate fin 1 is in contact with the outer protrusion 11b1 of the upper plate fin 1, and the inner protrusion 11b2 of the lower plate fin is fitted into the outer protrusion 11b1 of the upper plate fin (see Figures 4(a) and (c)).

[0022] In this state, by passing (inserting) the heat transfer tube H through each of the through holes 11 of the upper plate fin 1 and the lower plate fin 1, the inner protrusion 11b2 of the lower plate fin 1, which is in close contact with the heat transfer tube H, is spread outward by the heat transfer tube H and comes into close contact with the outer protrusion of the upper plate fin 1 (see Figures 4(b) and (d)). As a result, the lower plate fins and the upper plate fins are held parallel to each other at a fixed distance by the heat transfer tubes H, completing the heat exchanger.

[0023] 4. Heat exchanger operation If a heat exchanger created in this way is used, for example, as an in-vehicle heater, air heated by exhaust heat from an engine, motor, etc. is sent as a heat medium to heat the heat transfer tube H. The heated air sent to the heat transfer tube H heats the heat transfer tube H. Here, air for heating the vehicle cabin, for example, flowing from the right side to the left side of the page in FIG. 4, hits the heat transfer tube H and is heated, and by sending this air to the vehicle cabin, the temperature in the vehicle cabin is raised.

[0024] 5.Improved heat transfer efficiency At that time, as described above, the inner protruding portion 11b2 of the lower plate fin 1 is deformed outward and comes into a tight fit with the outer protruding portion 11b1 of the upper plate fin 1. As a result, the heat transfer tube H is supported straight along its penetration direction, and the plate fins 1 are securely held by the heat transfer tube H. The heat of the heat transfer tube H heated by the heated air is conducted to the heat sink plates 10 of each plate fin 1 via each inner protrusion 11b2, and the heat of these heat sink plates 10 also heats the air for heating the cabin that flows between the heat sink plates.

[0025] In addition, the surface area of ​​the plate fin 1 is increased by the raised portion 12, the outer protrusion 11b1 of the through hole 11, and the inner protrusion 11b2, which also enables the heat conducted by the heat transfer tube H to be transferred to the air for heating the cabin, thereby improving thermal conduction.

[0026] Furthermore, by providing the peripheral protrusion 11a, the strength of the periphery of the through hole 11 is increased, so that even if a heat transfer tube H is inserted into the through hole 11 of the plate fin 1, deformation is less likely to occur in the outer protrusion 11b1 of the upper plate fin 1 or the inner protrusion 11b2 of the lower plate fin 1, and the inner protrusion 11b2 of the lower plate fin 1 can be closely attached to the heat transfer tube H, thereby improving thermal conduction.

[0027] Furthermore, a raised portion 12 is formed in the center of every four mutually adjacent through holes 11, and both ends of the semi-cylindrical shape are parts of a quarter sphere. This quarter sphere generates turbulence in the cabin heating air that hits the raised portion 12, increasing the amount of cabin heating air that hits the heat transfer tube H. Therefore, this raised portion 12 can also more efficiently improve the heat transfer from the heat transfer tube to the cabin heating air.

[0028] 6. Effects of plate fin shape Incidentally, the plate fin 1 having such a shape is strengthened by providing the through holes 11, the raised portions 12, and the stepped portions 20 in the heat sink 10. This is because by forming the through holes 11, raised portions 12, and stepped portions 20 in the shapes described above, the cross-sectional shape of the heat sink, which was originally a flat plate, changes, increasing the resistance of the heat sink to bending. As a result, the heat sink has increased strength against bending, flexure, twisting, etc. Furthermore, by forming the through hole 11 as consisting of the peripheral protrusion 11a, the outer protrusion 11b1, and the inner protrusion 11b2, the strength of the heat sink 10 is further enhanced, and resistance to bending, flexure, twisting, etc. is improved.

[0029] As a result, no unnecessary deformation occurs when the heat transfer tubes are installed, and even if external forces are applied to the plate fins or the heat exchanger in which they are incorporated, or if corrosion, deterioration, creep, or other causes of strength deterioration occur over long-term use, these can be minimized as much as possible. Furthermore, since the through holes and the protruding portions protrude in opposite directions, resistance to bending, flexure, twisting, etc. in any direction can be increased. As a result, even if a soft metal such as aluminum or an aluminum alloy is used as the plate fin heat sink, the strength is ensured and the strength can be maintained without increasing long-term maintenance costs.

[0030] 7.Other Although the heat sink 10 is rectangular in shape, it may have any other shape. There is no particular limit to the thickness of the heat sink 10, but it can be within the range of 0.1 mm or more and 1.0 mm or less, for example.

[0031] In addition, the diameter of the through hole 11 is not particularly limited, but can be changed as appropriate according to, for example, the diameter of the heat transfer tube H. The shape of the through hole 11 is also not particularly limited, but can be, for example, a shape corresponding to the cross-sectional shape of the heat transfer tube.

[0032] The configuration of the peripheral protrusion 11a is not particularly limited, but may be, for example, an annular shape corresponding to the periphery of the through-hole 11. The extrusion deformation of the peripheral protrusion 11a may be performed, for example, by pressing. In addition, there is no particular restriction on the size of the peripheral protrusion 11a in the direction perpendicular to the penetration direction of the heat transfer tube H (e.g., the width of the annulus), but the size can be, for example, in the range of 1 / 6 or more and 1 / 2 or less of the diameter of the through hole 11. Furthermore, there is no particular limit to the extrusion depth of the peripheral projection 11a, but it can be within the range of 0.1 mm or more and 1.0 mm or less, for example.

[0033] Furthermore, the outer protrusion 11b1 may be, for example, approximately perpendicular to the other main surface 10b of the heat sink 10. Furthermore, there is no particular limit to the height of the outer protrusion 11b1, but it may be, for example, within the range of 0.5 mm to 3 mm. The second angle α of the inner protrusion 11b2 is not particularly limited, but may be, for example, within a range of 5 degrees or more and 30 degrees or less. The height of the inner protrusion 11b2 is preferably higher than the height of the outer protrusion 11b1, and may be, for example, within a range of 1 mm or more and 8 mm or less.

[0034] Further, the through-hole body 11b has outer protrusion 11b1 and inner protrusion 11b2 each having a different angle, but it is preferable that the through-hole body 11b is formed as a single piece so that the diameter narrows continuously toward the tip.

[0035] Furthermore, the stepped portions 20 cause the areas near the pair of long sides of the heat sink 10 to rise slightly higher in the protruding direction of the through-hole than the other areas, but conversely, they may be formed to be slightly lower.

[0036] In addition, there are no particular restrictions on the arrangement of the through holes 11 in the heat sink 10, and the center of the through hole 11 does not have to strictly coincide with a lattice point on the heat sink 10. The multiple through holes 11 may be evenly arranged along a straight line, may be arranged in a staggered pattern, or may be arranged in an arc or serpentine pattern.

[0037] In addition, there is no particular limit to the number of through holes 11 in the heat sink 10, but the number may be changed as appropriate depending on the type of heat exchanger to be applied, for example, 12 or 18 per heat sink 10 as shown in FIG. 1.

[0038] Furthermore, there are no particular limitations on the arrangement of the raised portions 12, and they do not have to strictly coincide with the centers of the four through holes. Multiple raised portions 12 may be evenly arranged along a straight line, or may be arranged in a staggered pattern, or may be arranged in an arc or serpentine pattern.

[0039] Furthermore, examples of applications of the plate fins 1 and the heat exchanger constructed using the same include industrial boilers and steam generators, as well as air conditioners, refrigerators, automobiles, robots, and any other devices that require heat exchange.

[0040] Furthermore, the above-described embodiment of the plate fin is merely an example, and other structures and functions may be added. [Industrial Applicability]

[0041] As described above, the plate fin of the present invention is useful for all types of heat exchangers, and is effective as a plate fin that can maintain its strength even when a relatively soft metal such as aluminum or an aluminum alloy is used as the metal that constitutes the heat sink. [Explanation of symbols]

[0042] 1 Plate fin 10 Heat sink 10a One main surface 10b Other main surface 11 Through hole 11A Through hole row 11a Peripheral protrusion 11b Through-hole body 11b1 Outer protrusion 11b2 Inner protrusion 12 Ridges 12A Ridge row 20 Step H Heat exchanger tube

Claims

1. A heat sink plate having a plurality of through holes for passing the heat transfer tubes therethrough is provided, The plurality of through holes are A plurality of through-hole rows are provided on the heat sink, the through-hole rows being arranged adjacent to each other, a row of raised portions is provided between each of the rows of through holes, the row of raised portions being arranged adjacent to each other; Each through hole in the through hole row is The peripheral edge of the heat sink protrudes from one main surface side to the other main surface side of the heat sink, Each ridge in the row of ridges comprises: A plate fin protruding from the other main surface side of the heat sink plate toward one main surface side.

2. Each through hole in the through hole row is a flat peripheral protrusion that protrudes from one main surface of the heat sink to the other main surface of the heat sink, the flat peripheral protrusion having a step; a through hole main body protruding from the peripheral protruding portion toward the other main surface while decreasing an inner diameter thereof; The plate fin according to claim 1 , having

3. The plate fin according to claim 1 , wherein the heat sink has a stepped portion on a periphery thereof that rises from one main surface side to the other main surface side or from the other main surface side to the one main surface side.

4. The plate fin according to claim 1 , wherein the heat sink is made of aluminum or an aluminum alloy.

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