JP2011007412A - Oil cooler - Google Patents

Abstract

PROBLEM TO BE SOLVED: To improve heat exchange efficiency and avoid generation of cracks due to thin walls during press working by increasing the total number of protrusions 31, 32 in cooling water flow paths 8.SOLUTION: In the core part 1 of an oil cooler, a number of first core plates 5 and second core plates 6, which have fundamental shapes in common, are alternately laminated and oil flow paths 7 and cooling water flow paths 8 are formed alternately between the respective core plates 5, 6. Fin plates 11 are put respectively in a sandwiched manner in the oil flow paths 7. The first protrusions 31 of a truncated cone shape are press-worked upward on the first core plates 5 and the second protrusions 32 of a truncated cone shape are press-worked downward on the second core plates 6, so that they protrude into the cooling water flow paths 8. The respective protrusions 31, 32 are arranged in a complementary relationship.

Description

  The present invention relates to a so-called multi-plate laminated type oil cooler used for cooling, for example, lubricating oil of an internal combustion engine or hydraulic oil of an automatic transmission.

  For example, as disclosed in Patent Document 1 or Patent Document 2, as an oil cooler for lubricating oil for internal combustion engines or hydraulic oil for automatic transmissions, an oil flow path and a cooling water flow path are formed by laminating many core plates. A so-called multi-plate laminated water-cooled oil cooler is known.

  When attention is paid to the cooling water flow path formed between the two core plates, a plurality of protrusions protruding into the cooling water flow path are formed on either one of the core plates. The top of the protrusion is joined to the flat surface of the other core plate. This protrusion contributes to an improvement in heat exchange efficiency with the cooling water flowing in the cooling water flow path and an improvement in the rigidity of the laminated core portion. In Patent Document 1, a relatively small protrusion that forms a truncated cone shape. A large number of so-called dimples are arranged, and in Patent Document 2, a hemispherical protruding portion is arranged so as to surround a central cylindrical portion.

  In other words, as the core plate, there are a plurality of protrusions formed by bulging and a flat surface not including the protrusions, and both are alternately laminated.

JP 2006-183903 A JP 2007-278614 A

  As described above, in the conventional multi-plate laminated type oil cooler, all the plurality of protrusions protruding into the cooling water flow path are provided on one core plate. In general, the protrusions are formed at the same time when the core plate is pressed from a base material made of an aluminum alloy or the like. Thinning occurs at the base of the base and the protrusions.

  Therefore, if more protrusions are arranged to improve the heat exchange efficiency, cracks due to thinning tend to occur during press working. Moreover, in order to avoid this, it is necessary to set the thickness of the core plate (base material) to be thicker, which leads to an increase in the weight and cost of the oil cooler.

  Therefore, in the present invention, the protrusions are arranged on both of the two core plates facing each other across the cooling water flow path. That is, according to the present invention, a plurality of first core plates and second core plates whose peripheral portions are joined to each other are alternately stacked, and the first surface of the first core plate and the second core plate are The oil flow path between the second surface and the cooling water flow path between the first surface of the second core plate and the second surface of the first core plate are alternately configured. In the oil cooler, the first core plate bulges and forms a large number of first protrusions that protrude toward the cooling water flow path and whose top abuts against the first surface of the second core plate. The second core plate is characterized in that a large number of second protrusions projecting toward the cooling water flow path and projecting from the top of the second core plate are in contact with the second surface of the first core plate.

  Preferably, the second protrusion is located in a region surrounded by the plurality of first protrusions, and at the same time, the first protrusion is in the region surrounded by the plurality of second protrusions. As shown, the arrangement of the first protrusions on the first core plate and the arrangement of the second protrusions on the second core plate are complementary.

  By providing protrusions on both the first core plate and the second core plate as described above, a part of the total number of necessary protrusions is on the first core plate and the remaining part is the second core. Each plate is processed, and the density of the protrusions to be processed on each core plate is reduced.

  According to the present invention, since the number of protrusions processed in each core plate is smaller than the total number of necessary protrusions, it is possible to suppress the occurrence of cracks due to thinning during processing, and the total number of protrusions Even when increasing the thickness, it is possible to use a thin core plate. In addition, it is possible to provide a large number of protrusions in the cooling water flow path, and heat exchange efficiency and rigidity can be improved by generating turbulent flow.

1 is an exploded perspective view showing a basic configuration of an oil cooler according to the present invention. The top view of a 1st core plate. The top view of the 2nd core plate. The top view which projects and shows arrangement | positioning of a projection part when two types of core plates are piled up. Sectional drawing along the AA line of FIG. The top view of the 1st core plate in 2nd Example. The top view of the 2nd core plate in 2nd Example. The top view similar to FIG. 4 in 2nd Example. Sectional drawing along the BB line of FIG. Sectional drawing of 3rd Example from which the cone angle of a 1st projection part and a 2nd projection part differs.

  Hereinafter, an embodiment of the present invention will be described in detail with reference to the drawings. In the following description, in order to facilitate understanding, the terms “upper” and “lower” are used on the basis of the posture of FIG. 1, but the present invention is not limited to this.

  First, the basic configuration of the entire oil cooler will be described. As shown in the exploded perspective view of FIG. 1, the oil cooler includes a core portion 1 that performs heat exchange between oil and cooling water, This is generally composed of a relatively thick top plate 2 attached to the upper surface and bottom plates 3 and 4 attached to the lower surface of the core portion 1.

  The core portion 1 is formed by alternately laminating a large number of first core plates 5 and second core plates 6 having a common basic shape, and between each of the core plates 5 and 6, an oil flow path 7 and The cooling water flow paths 8 are alternately configured (see FIG. 5). In the illustrated example, an oil flow path 7 is formed between the lower surface of the first core plate 5 and the upper surface of the second core plate 6, and the lower surface of the second core plate 6 and the upper surface of the first core plate 5. The cooling water channel 8 is formed between the two. A substantially rectangular fin plate 11 is sandwiched in each oil flow path 6.

  The first core plate 5 and the second core plate 6 are formed by press-molding a thin base material of an aluminum alloy, and as shown in FIGS. Oil communication holes 12 are formed at two positions on the diagonal, and cooling water communication holes 13 are formed at two positions on different diagonal lines. In the first core plate 5, the periphery of the oil communication hole 12 is formed as a boss portion 14 so as to protrude to the cooling water flow path 8 side. In the second core plate 6, the cooling water communication hole is formed. 13 is formed as a boss 15 so as to protrude to the oil flow path 7 side. Accordingly, the two kinds of core plates 5 and 6 are alternately combined, so that a constant interval for forming the flow paths 7 and 8 is maintained between the core plates 5 and 6.

  Here, the boss portions 14 around the oil communication hole 12 in the first core plate 5 are joined to the periphery of the oil communication hole 12 in the adjacent second core plate 6, respectively. The flow paths 7 communicate with each other and are isolated from the cooling water flow path 8 therebetween. In this way, in a state where a large number of core plates 5 and 6 are joined, the oil flow paths 7 communicate with each other through a large number of oil communication holes 12, and the oil flows up and down in the core portion 1 as a whole. It can flow in the direction.

  In FIG. 1, the oil communication holes 12 of the core plates 5 and 6 are drawn at positions where they are vertically aligned. In the core plates 5 and 6, one of the pair of oil communication holes 12 is closed so that the oil flows while making a U-turn left and right as a whole.

  Further, the cooling water communication hole 13 has the same configuration as that of the oil communication hole 12, and the boss portion 15 around the cooling water communication hole 13 in the second core plate 6 is adjacent to the first core plate 5. The cooling water communication holes 13 are joined to each other so that the upper and lower cooling water flow paths 8 communicate with each other and are isolated from the oil flow path 7 between them. Therefore, in the state where a large number of core plates 5 and 6 are joined, the cooling water flow paths 8 communicate with each other via the large number of cooling water communication holes 13, and the cooling water flows vertically in the core portion 1 as a whole. To be able to flow through.

  The peripheral portions 5a and 6a of the core plates 5 and 6 are tapered outwardly, and in a state where the core plates 5 and 6 are stacked, the peripheral portions 5a and 6a come into close contact with each other. Yes. In addition, tapered cylindrical portions 5b and 6b projecting in a substantially conical shape are provided at the center of each of the core plates 5 and 6, and a large number of the tapered cylindrical portions 5b and 6b are sequentially overlapped to form the core portion. A central oil passage 17 penetrating up and down 1 is formed. The central oil passage 17 is not in direct communication with the oil passage 7 between the core plates 5 and 6.

  The fin plate 11 sandwiched between the oil flow paths 7 is formed with openings 18 corresponding to the oil communication holes 12 and the cooling water communication holes 13 at four positions on the diagonal line, and the center. A through hole 19 corresponding to the central oil passage 17 (tapered cylindrical portions 5b, 6b) is formed in the portion. The opening 18 is slightly larger than the communication holes 12 and 13 so as to have a slight margin with respect to the boss 15. Note that the fin plate 11 in FIG. 1 is schematically drawn, and is actually formed in a so-called fin shape as a whole.

  The top plate 2 is further laminated on the top of the core portion 1. The top plate 2 includes a cooling water introduction pipe 21 that communicates with one of the pair of cooling water communication holes 13 at the top of the core section 1 and a cooling water discharge pipe 22 that communicates with the other. Further, the top plate 2 has a bulging portion 23 along one diagonal line, and by this bulging portion 23, one oil communication hole 12 at the top of the core portion 1 and the upper end of the central oil passage 17 are mutually connected. A communication path (not shown) that communicates is configured.

  As described above, the relatively thick bottom plates 3 and 4 having sufficient rigidity are laminated on the lower portion of the core portion 1. These bottom plates 3 and 4 are provided with an oil inlet 25 opened corresponding to one of the oil communication holes 12 at the lowermost part of the core portion 1 and an oil outlet 26 opened corresponding to the central oil passage 17. It is attached to a cylinder block or the like (not shown) via gaskets 27, 27 for sealing each.

  Accordingly, as the oil flow, oil that has become hot due to lubrication of each part of the internal combustion engine is introduced from the oil inlet 25 of the bottom plates 3 and 4 into the respective oil flow paths 7 of the core part 1 and is adjacently cooled. After being cooled by exchanging heat with the cooling water flowing through the water flow path 8, it flows to the central oil passage 17 via the communication path by the bulging portion 23 of the top plate 2, and finally the bottom plates 3, 4. From the oil outlet 26 to the internal combustion engine side. It is also possible to reverse the oil flow so that hot oil is introduced into the central oil passage 17 and heat exchange is performed in the core portion 1 and then returned to the internal combustion engine from the lowermost oil communication hole 12. is there. Further, the cooling water is distributed from the cooling water introduction pipe 21 to the respective cooling water flow paths 8 through the cooling water communication holes 13 arranged vertically, and the inside of each cooling water flow path 8 from the one cooling water communication hole 13 to the other. It flows toward the cooling water communication hole 13 and finally flows out to the cooling water discharge pipe 22.

  The numerous core plates 5 and 6, the fin plate 11, the top plate 2, and the bottom plates 3 and 4 described above are joined and integrated together by brazing. Specifically, each of these parts is formed using a so-called clad material in which a brazing material layer is coated on the surface of an aluminum alloy substrate, and each part is heated in a furnace in a temporarily assembled state at a predetermined position. By doing so, it is brazed together.

  The core plates 5 and 6 positioned at the uppermost and lowermost portions of the core portion 1 are generally core plates 5 positioned at the intermediate portion of the core portion 1 due to the relationship with the top plate 2 and the bottom plates 3 and 4. , 6 has a slightly different configuration.

  Next, the protrusion part which protrudes in the cooling water flow path 8 which is the principal part of this invention is demonstrated.

  As described above, the cooling water flow path 8 through which the cooling water flows is formed between the core plates 5 and 6, specifically between the lower surface of the second core plate 6 and the upper surface of the first core plate 5. However, the first core plate 5 positioned relatively below has a large number of first protrusions 31 protruding from the cooling water flow path 8 side, that is, upward. The bulging direction of the first protrusion 31 is on the same side as the peripheral portion 5a and the tapered cylindrical portion 5b of the first core plate 5 rise upward. The first protrusion 31 has a truncated cone shape, and its height is equal to the height of the boss 14 described above. Therefore, in the assembled state, as shown in FIG. Are joined to the lower surface (flat surface) by brazing.

  Similarly, the second core plate 6 positioned relatively upward is formed with a large number of second protrusions 32 protruding from the cooling water flow path 8 side, that is, downward. The bulging direction of the second projecting portion 32 is opposite to the peripheral portion 6a and the tapered cylindrical portion 6b of the second core plate 6 rising upward. This second protrusion 32 also has the same truncated cone shape as the first protrusion 31, and its height is equal to the height of the boss 14 described above. Therefore, in the assembled state, as shown in FIG. The top is joined to the upper surface (flat surface) of the first core plate 5 by brazing. These protrusions 31 and 32 are both formed at the same time when the core plates 5 and 6 are pressed. However, in the actually formed state, the top is somewhat rounded, so that the dome shape is formed. The frustoconical shape approximates to.

  2 and 3 show an example of the arrangement of a large number of protrusions 31 and 32. In this example, a large number of protrusions 31 and 32 are arranged along a row / column direction inclined by 45 ° with respect to the quadrangle of the core plates 5 and 6. The protrusions 31 and 32 are regularly arranged at regular intervals. The position of the first protrusion 31 on the first core plate 5 (FIG. 2) and the position of the second protrusion 32 on the second core plate 6 (FIG. 3) are complementary to each other. As shown in FIG. 4 which is a projection of the arrangement when the two are overlapped, one second protrusion at the center of the quadrangular region surrounded by the four first protrusions 31 In contrast, one first protrusion 31 is positioned at the center of a rectangular region surrounded by the four second protrusions 32. In other words, as shown in FIG. 4, as a whole, the protrusions 31 and 32 combined with each other have a large number of protrusions 31 and 32 along the rectangular vertical and horizontal row and column directions of the core plates 5 and 6. Thus, the first protrusions 31 and the second protrusions 32 are alternately arranged when viewed in the row / column direction.

  In this way, by distributing the projections 31 and 32 evenly to the first core plate 5 and the second core plate 6 respectively, two adjacent projections 31 processed into the same core plates 5 and 6 are provided. The minimum distance between 32 is secured larger, and the risk of cracking due to thinning during press working is reduced accordingly. Further, it is not necessary to increase the thickness of the core plates 5 and 6 in consideration of thinning.

  Therefore, it is possible to set a sufficiently large total number of the protrusions 31 and 32 in the cooling water flow path 8 without being restricted by the occurrence of cracks or the like at the time of press working, and by generating turbulent flow at the protrusions 31 and 32. The heat exchange efficiency can be improved. Further, since the hydraulic pressure in the oil flow path 7 is considerably higher than the pressure of the cooling water in the cooling water flow path 8, the core plates 5 and 6 are pressed in the direction in which the cooling water flow path 8 becomes narrow. By disposing a large number of protrusions 31 and 32 in the water channel 8, the rigidity thereof is increased.

  Further, in the illustrated example, the first protrusion is formed in a narrow region between the oil communication hole 12 (boss portion 14) in the first core plate 5 and the peripheral edge portion 5a adjacent thereto (that is, a rectangular corner portion). The part 31 does not exist, and the second protrusion 32 indicated by reference numeral 32A in FIG. 4 is disposed at this position.

  As described above, in the first core plate 5, the first protrusion 31 is bulged and formed in the same direction as the peripheral edge 5a and the boss part 14 (that is, upward). If the first projecting portion 31 is to be formed, the boss portion 14, the projecting portion 31 and the peripheral portion 5a come close to each other, and drawing with a press becomes relatively difficult. On the other hand, if the protrusion of this part is provided on the second core plate 6 as the second protrusion 32A, the protrusion 32A bulges in the direction opposite to the peripheral edge 6a of the core plate 6. Since it is molded and the oil communication hole 12 is a simple opening (that is, it does not include the boss portion 14), drawing by a press is facilitated.

  As described above, in the present invention, an alternative protrusion is disposed on the other core plate 5 or 6 where it is difficult to provide the protrusion on one of the two types of core plates 5 and 6. As a result, the overall processing cost and yield can be improved.

  In the example of FIGS. 2 to 4, the protrusions 31 and 32 are arranged perfectly regularly for the sake of simplification. However, various requests, for example, from one cooling water communication hole 13 to the other. In order to improve the characteristics of the flow to the cooling water communication hole 13, the arrangement of the protrusions 31 and 32 is not completely regular but may be slightly distorted. Moreover, the 1st projection part 31 and the 2nd projection part 32 do not need to be completely equal arrangement | positioning.

  Next, FIGS. 6 to 9 show a second embodiment in which the protrusions 31 and 32 are arranged differently. 6 shows the arrangement of the first protrusions 31 on the first core plate 5, FIG. 7 shows the arrangement of the second protrusions 32 on the second core plate 6, and FIG. The state is projected. In this embodiment, the basic positions of the protrusions 31 and 32 are similar to those of the above-described embodiment, but in particular, in the outer peripheral portions of the core plates 5 and 6, the protrusions compared to FIGS. The number of 31 and 32 has decreased. In other words, the central portions of the core plates 5 and 6 are dense and the outer peripheral portions of the core plates 5 and 6 are rough as the distribution density of the total protrusions 31 and 32 shown in FIG. According to such distribution of the protrusions 31 and 32, when the cooling water flows from one cooling water communication hole 13 to the other cooling water communication hole 13, the flow does not flow linearly between the two and to the outer peripheral portion. In this case, the cooling water is guided, and heat exchange is performed using the entire surface of the core plates 5 and 6 widely. In particular, in the present invention, by using both the core plates 5 and 6 in the portions where the protrusions 31 and 32 should be densely arranged, more protrusions can be obtained without being restricted by cracks due to thinning. It is possible to arrange | position 31 and 32 intensively, and can adjust the flow of a cooling water appropriately.

  Next, FIG. 10 shows a third embodiment of the present invention. In this embodiment, a first projection 31 having a truncated cone shape and a second projection 32 having a truncated cone shape, respectively. The cone angle is different. For example, the cone angle of the first protrusion 31 is larger than the cone angle of the second protrusion 32. Thus, when the cone angles of the projecting portions 31 and 32 having a truncated cone shape are different, the first projecting portion 31 and the second projecting portion 32 are combined even in a region where both are arranged very densely. In the state, the flow path, that is, the gap remains reliably between the two, and the flow of the cooling water is ensured. In FIG. 10, the first protrusion 31 and the second protrusion 32 are drawn at positions relatively separated for the sake of explanation.

  As mentioned above, although one Example of this invention was described, this invention is not restricted to the said Example, A various change is possible. For example, in the above embodiment, the first core plate 5 and the second core plate 6 are provided with approximately the same number of protrusions 31 and 32, respectively. For example, the distance between the protrusions is compared. Compare the number of protrusions by placing protrusions only on one of the core plates in a large area and placing protrusions on both core plates in areas where the protrusions are densely arranged. You may make it differ greatly. Further, the shape of the protruding portion may be a shape other than the above-mentioned frustoconical shape, such as a cylindrical shape, and the first protruding portion and the second protruding portion may be different in shape. Further, in the above embodiment, the top of the first protrusion and the lower surface (flat surface) of the second core plate and the top of the second protrusion and the upper surface (flat surface) of the first core plate are brazed. However, when the oil pressure in the oil flow path is low, it is possible to simply contact each other without brazing.

DESCRIPTION OF SYMBOLS 1 ... Core part 5 ... 1st core plate 6 ... 2nd core plate 7 ... Oil flow path 8 ... Cooling water flow path 11 ... Fin plate 12 ... Oil communication hole 13 ... Cooling water communication hole 31 ... 1st protrusion part 32. Second protrusion

Claims (4)

A plurality of first core plates and second core plates whose peripheral portions are joined to each other are alternately stacked, and the first surface of the first core plate and the second surface of the second core plate In the oil cooler, wherein the oil flow path between and the cooling water flow path between the first surface of the second core plate and the second surface of the first core plate are alternately configured,
The first core plate bulges and forms a large number of first protrusions that protrude toward the cooling water flow path and whose top abuts against the first surface of the second core plate.
An oil cooler characterized in that a large number of second protrusions protruding from the second core plate and projecting toward the cooling water flow path are in contact with the second surface of the first core plate. .   The second protrusion is positioned in the region surrounded by the plurality of first protrusions, and at the same time, the first protrusion is positioned in the region surrounded by the plurality of second protrusions. 2. The oil cooler according to claim 1, wherein the arrangement of the first protrusions on the first core plate and the arrangement of the second protrusions on the second core plate are complementary.   The said 1st protrusion part and the said 2nd protrusion part each comprise a truncated cone shape, The flow of the cooling water in the said cooling water flow path is adjusted with the density of the distribution, The 1 or 2 characterized by the above-mentioned. Oil cooler described in 1.   4. The oil cooler according to claim 1, wherein each of the first protrusion and the second protrusion has a truncated cone shape and has a different cone angle.

Images