Cooling heat exchanger

Abstract

Provided is a cooling heat exchanger having a novel structure with which a double-sided cooling structure having a cooling surface on both sides is realized in a simple structure, and with which excellent cooling performance can be stably obtained.　A cooling heat exchanger 10 has formed in the interior thereof a cooling channel 28 through which a cooling heat medium flows, and the cooling heat exchanger cools a cooling object 62 that is layered on a cooling surface 32 provided on the surface of the cooling heat exchanger. A hollow outer wall member 12 having the cooling channel 28 therein is provided. A pair of cooling wall parts 30, 30 each have the cooling surface 32 on a surface of the cooling wall parts, and the cooling wall parts are provided to mutually opposing sections of the outer wall member 12. In an internal region 28 of the outer wall member 12, arranged is a plate-like inner fin 34 bisecting the internal region 28 in the opposing direction of the pair of cooling wall parts 30, 30. A first projection 48a and a second projection 48b, each protruding to opposing surfaces, are formed integrally in the inner fin 34.

Description

cooling heat exchanger

[0001] The present invention relates to a cooling heat exchanger used to cool an object to be cooled, such as a battery used in an electric vehicle.

[0002] Conventionally, cooling heat exchangers used for cooling batteries and inverters have been known. As disclosed in, for example, Japanese Patent No. 7000777 (Patent Document 1), the cooling heat exchanger has a structure in which a cooling flow path through which a heat medium flows is formed inside an outer wall member. An object to be cooled, such as a battery, is placed on a cooling surface provided on the surface, and the object to be cooled is cooled by heat exchange between the object to be cooled and the heat medium.

[0003] In addition, the cooling heat exchanger of Patent Document 1 has a pair of cooling wall sections that constitute an outer wall member arranged opposite each other, and cooling surfaces are set on both outer surfaces of the pair of cooling wall sections, and has a double-sided cooling structure that can cool a cooling object that is superimposed on the cooling surfaces set on both sides.

[0004] Patent No. 7000777

[0005] In Patent Document 1, inner fins are housed inside the outer wall member in order to increase the contact area with the heat transfer medium and improve the cooling efficiency of the cooling surface by the heat transfer medium. In Patent Document 1, for the purpose of efficient double-sided cooling, the internal space of the outer wall member is divided by an intermediate plate in the opposing direction of the pair of cooling wall sections, and inner fins are arranged on both sides of the intermediate plate.

[0006] However, the structure of Patent Document 1 requires an intermediate plate and two inner fins, which increases the number of parts and makes the structure complicated.

[0007] In addition, since only the heat medium flowing in a position close to the object to be cooled becomes hot due to heat exchange with the object, there is a risk that the cooling performance due to heat exchange with the heat medium flowing in a position close to the object to be cooled will be reduced. Furthermore, since the heat medium flowing in a position far from the object to be cooled indirectly cools the object to be cooled via the intermediate plate and inner fins, the heat exchange efficiency is likely to be lower than that of the heat medium flowing in a position close to the object to be cooled, and the heat capacity of the entire heat medium cannot be effectively used, which may result in a reduction in cooling performance.

[0008] The problem to be solved by the present invention is to provide a cooling heat exchanger of a novel structure that can realize a double-sided cooling structure with cooling surfaces on both sides with a simple structure while stably obtaining excellent cooling performance.

[0009] The following describes preferred embodiments for understanding the present invention, but the embodiments described below are merely examples and may be appropriately combined with one another. Multiple components described in each embodiment may be recognized and employed independently to the greatest extent possible, and may also be appropriately combined with any of the components described in other embodiments. Accordingly, the present invention is not limited to the embodiments described below, and various other embodiments may be realized.

[0010] The first aspect is a cooling heat exchanger that has a cooling flow path formed inside through which a cooling heat medium flows and that cools a cooling object that is placed over a cooling surface provided on the surface, and that has a hollow outer wall member with the cooling flow path inside, and a pair of cooling wall portions with the cooling surface on their surfaces provided at mutually opposing portions of the outer wall member, and a plate-shaped inner fin is arranged in the internal region of the outer wall member, dividing the internal region into two in the opposing direction of the pair of cooling wall portions, and the inner fin has a first protrusion and a second protrusion integrally formed on each of the inner fins, protruding from one side.

[0011] In the heat exchanger for cooling constructed according to this aspect, the cooling flow path is divided into two by one inner fin in the direction in which the pair of cooling walls face each other, thereby realizing a divided cooling flow path suitable for double-sided cooling with a simple structure. Furthermore, for example, by providing the inner fin in the internal region of the outer wall member, the contact area with the heat medium is increased, and therefore the pair of cooling walls are also cooled by indirect heat exchange with the heat medium via the inner fin, thereby improving the cooling performance for the object to be cooled.

[0012] The inner fins are integrally formed with first and second protrusions that protrude from one surface of each fin. Therefore, the heat medium flowing on both sides of the inner fin is agitated by the first and second protrusions, for example, by generating vortices or turbulence, or by being guided away from the inner fin toward the cooling wall. The heat medium is then agitated by the heat medium flowing near the cooling wall, which has been heated by heat exchange with the object to be cooled, and the heat medium flowing far from the cooling wall (close to the inner fin), which is maintained at a relatively low temperature, and these heat mediums with different temperatures are mixed. This prevents a decrease in the efficiency of heat exchange with the object to be cooled due to a partial temperature increase of the heat medium, and effectively utilizes the entire heat capacity of the heat medium to cool the object to be cooled, thereby improving cooling performance.

[0013] Since the first and second protrusions are provided protruding from both sides of the inner fin that separates the cooling flow path, the stirring action of the protrusions can be obtained in the flow paths on both sides of the inner fin with a small number of parts and manufacturing processes.

[0014] In a second aspect, in the cooling heat exchanger described in the first aspect, the cooling flow path has a parallel flow path section composed of a plurality of flow path sections that are separated in the flow path width direction by the inner fins and extend adjacent to each other in parallel, and the flow direction of the heat medium in the plurality of flow path sections that make up the parallel flow path section is the same.

[0015] In the cooling heat exchanger constructed according to this aspect, the inner fins are used to form parallel flow passages consisting of a plurality of parallel flow passages, and the inner fins can also function as flow straightening fins to straighten the flow of the heat medium. Furthermore, the flow passage cross-sectional area of ​​each flow passage can be easily adjusted by the inner fins, and the flow rate and flow velocity of the heat medium in each flow passage can be adjusted to achieve the desired cooling performance.

[0016] Since the inner fins form walls that separate adjacent flow path sections, the contact area of ​​the inner fins with the heat medium is increased, thereby achieving more efficient indirect cooling of the cooling surface via the inner fins.

[0017] The size of the parallel flow path section consisting of multiple flow path sections in the flow path width direction can be adjusted by the number of flow path sections. Therefore, for example, by arranging the parallel flow path sections at positions corresponding to the cooling surface, the flow path cross-sectional area of ​​each flow path section can be appropriately set, and the size of the cooling surface in the flow path width direction can be set with greater freedom.

[0018] The flow direction of the heat medium in the multiple flow path sections that make up the parallel flow path section is the same as each other, so that a decrease in cooling performance due to heat exchange between adjacent flow path sections is unlikely to occur.

[0019] In a third aspect, in the cooling heat exchanger described in the first or second aspect, the outer wall member is constructed by stacking a first member constituting one of the cooling wall portions and a second member constituting the other cooling wall portion in the opposing direction of the pair of cooling wall portions, and the inner fin is arranged between the opposing first member and second member.

[0020] According to a cooling heat exchanger constructed in accordance with this aspect, by arranging inner fins between the overlapping surfaces of the first member and the second member, the inner fins can be easily accommodated and positioned in the internal region of the outer wall member.

[0021] A fourth aspect is a cooling heat exchanger described in any one of the first to third aspects, wherein the inner fin has a cross section that is folded back in a zigzag or wavy manner in the opposing direction of the pair of cooling wall portions, and the first protrusion and the second protrusion are formed between the tops of adjacent folds in the inner fin.

[0022] In the cooling heat exchanger constructed according to this aspect, the inner region of the outer wall member can be divided by the inner fins having a simple shape. In particular, if the inner fins have a zigzag or wavy cross section, it is possible to form multiple parallel flow passages separated by the inner fins.

[0023] Furthermore, since the inner fin has a cross section that is folded back in a zigzag or wave shape, it is easier to ensure the deformation rigidity of the inner fin, and it is possible to, for example, make the inner fin thinner. Moreover, by forming the first protrusion and the second protrusion between the apexes of the folds of the inner fin, the deformation rigidity of the inner fin can be further increased.

[0024] A fifth aspect is a cooling heat exchanger described in any one of the first to third aspects, wherein the inner fin is positioned away from both of the pair of cooling wall portions in the outer wall member and has an intermediate partition portion that divides the opposing surfaces of the pair of cooling wall portions into two in the opposing direction of the pair of cooling wall portions, the first protrusion and the second protrusion are formed on the intermediate partition portion, the inner fin has partition portions that protrude on both sides from the intermediate partition portion toward the pair of cooling wall portions, and the partition portions divide the internal region of the outer wall member into a plurality of flow path portions in the flow path width direction of the cooling flow path.

[0025] In a cooling heat exchanger constructed according to this aspect, the internal region of the outer wall member is divided by one inner fin not only in the opposing direction of the pair of cooling walls but also in the width direction of the cooling flow path to form a plurality of flow path sections, which makes it possible to easily set the number of flow path sections and the flow path cross-sectional area with a great degree of freedom by changing the spacing and number of partition walls provided on one inner fin.

[0026] Since the first and second protrusions are provided on the intermediate partition portion, the protrusions exert a turbulent flow promoting effect in each flow path region, thereby achieving excellent cooling performance.

[0027] In a sixth aspect, in the cooling heat exchanger described in any one of the first to fifth aspects, the first protrusion and the second protrusion are V-shaped on the surface of the inner fin and narrow toward the upstream side of the cooling flow path.

[0028] In a cooling heat exchanger constructed according to this aspect, when the heat medium passes over the first or second V-shaped protrusions, it flows in a direction inclined toward the center of the V in the flow path width direction so as to reduce flow resistance. As a result, the heat medium flows that have passed over the first or second protrusions merge with each other, generating vortexes and turbulence downstream of the first or second protrusions. As a result, the heat medium is more efficiently agitated, reducing the temperature difference of the heat medium (uniformizing the temperature) and improving cooling performance.

[0029] In a seventh aspect, in the cooling heat exchanger according to any one of the first to sixth aspects, the inner fins are arranged partially in the flow path length direction of the cooling flow path.

[0030] The cooling heat exchanger constructed according to this embodiment can achieve weight and cost reduction by, for example, eliminating inner fins in areas where double-sided cooling is not required. In areas where double-sided cooling is required, inner fins equipped with first and second protrusions are provided, which can be expected to provide high cooling performance by stirring the heat transfer medium.

[0031] In an eighth aspect, in a cooling heat exchanger described in any one of the first to seventh aspects, regions are set in the cooling flow path in which at least one of the plurality of first protrusions and the plurality of second protrusions has a different effect on disturbing the flow of the heat medium.

[0032] According to a cooling heat exchanger constructed in accordance with this embodiment, for example, when there are portions on the cooling surface where different cooling performance is required, by strengthening the effect of disturbing the flow of the heat medium in the portion where higher cooling performance is required, it is possible to achieve partial improvement of cooling performance by promoting turbulence.

[0033] In a ninth aspect, in the cooling heat exchanger described in the eighth aspect, the areas having different effects of disturbing the flow of the heat medium are set at different positions in the cooling flow path in the flow direction of the heat medium.

[0034] In a cooling heat exchanger constructed according to this embodiment, the turbulence-promoting effect that disturbs the flow of the heat medium differs depending on the flow direction of the heat medium. Therefore, for example, if a portion where the temperature difference between the heat medium close to the object to be cooled and the heat medium far from the object to be cooled is likely to become large and a portion where the temperature difference between the heat medium is unlikely to become large are located at different positions in the flow direction of the cooling flow path, the temperature difference in the flow direction of the heat medium can be reduced by setting an area with a strong turbulence-promoting effect in the portion where the temperature difference between the heat medium close to the object to be cooled and the heat medium far from the object to be cooled is likely to become large.

[0035] Furthermore, in the cooling flow path, in the portion where the temperature difference between the heat medium close to the object to be cooled and the heat medium far from the object to be cooled is unlikely to become large, a region where turbulence in the flow of the heat medium is suppressed can be set up, thereby realizing a smooth flow of the heat medium.

[0036] In a tenth aspect, in the cooling heat exchanger described in the ninth aspect, the regions set at different positions in the flow direction of the heat medium in the cooling flow path have different effects of disturbing the flow of the heat medium, and the more downstream the region is set, the stronger the effect of disturbing the flow of the heat medium.

[0037] With a cooling heat exchanger constructed in accordance with this embodiment, the temperature of the heat medium is made uniform by the stirring effect caused by turbulence in the flow of the heat medium downstream, where the temperature difference between the heat medium flowing in a position close to the object to be cooled and the heat medium flowing in a position far from the object to be cooled is likely to be large, thereby enabling high cooling performance to be achieved.

[0038] In an eleventh aspect, in the cooling heat exchanger described in any one of the eighth to tenth aspects, the cooling flow path has a parallel flow path section made up of a plurality of flow path sections that are separated by the inner fins and extend adjacent to each other in parallel, the flow direction of the heat medium in the plurality of flow path sections that make up the parallel flow path section is the same, and at least one pair of adjacent flow path sections in the parallel flow path section are set with the regions that have different effects of disturbing the flow of the heat medium.

[0039] With a cooling heat exchanger constructed in accordance with this aspect, for example, when the heat generation amount of the object to be cooled varies in the flow path width direction, it is possible to set the turbulence of the heat medium flow to be strong in areas where the heat generation amount of the object to be cooled is large, and to set the turbulence of the heat medium flow to be weak in areas where the heat generation amount of the object to be cooled is small, thereby making it possible to stabilize the cooling performance.

[0040] In a twelfth aspect, in the cooling heat exchanger described in any one of the eighth to eleventh aspects, the areas having different effects of disturbing the flow of the heat medium are set by at least one of a difference in the distance between the plurality of first protrusions in the flow direction of the heat medium and a difference in the distance between the plurality of second protrusions.

[0041] In a cooling heat exchanger constructed according to this aspect, for example, by shortening the distance between the first projections and / or the distance between the second projections in the heat medium flow direction, it is possible to set an area with a strong effect of turbulence promotion on the heat medium flow, and by lengthening the distance between the first projections and / or the distance between the second projections, it is possible to set an area with a weaker effect of turbulence promotion. In this way, by varying the spacing between the first projections and / or the second projections, it is possible to easily set areas with different effects of turbulence promotion on the heat medium flow.

[0042] In a thirteenth aspect, in the cooling heat exchanger described in any one of the eighth to twelfth aspects, the areas having different effects of disturbing the flow of the heat medium are set by at least one of the difference in height between the plurality of first protrusions and the difference in height between the plurality of second protrusions.

[0043] In a cooling heat exchanger constructed according to this aspect, for example, by partially increasing the height of the first protrusions and / or the second protrusions, it is possible to set an area with a strong effect of disturbing the flow of the heat medium (turbulence promotion effect), and by partially decreasing the height of the first protrusions and / or the second protrusions, it is possible to set an area with a weaker effect of promoting turbulence. In this way, by varying the heights of the multiple first protrusions and / or the multiple second protrusions, it is possible to easily set areas with different effects of disturbing the flow of the heat medium.

[0044] A fourteenth aspect is the cooling heat exchanger according to any one of the first to thirteenth aspects, wherein the object to be cooled is a battery.

[0045] With a cooling heat exchanger constructed according to this aspect, for example, when cooling a battery that is prone to local temperature increases at the output terminals, etc., adjusting the arrangement of the first protrusions and / or second protrusions makes it possible to efficiently cool high-temperature portions of the battery. Furthermore, for example, when cooling a battery unit consisting of multiple batteries, adjusting the arrangement of the first protrusions and / or second protrusions makes it possible to effectively cool all of the multiple batteries, preventing a decrease in performance of the entire battery unit due to deterioration of a specific battery.

[0046] In a fifteenth aspect, in a cooling heat exchanger described in any one of the first to fourteenth aspects, the inner fin is provided with an elastic deformation portion that allows the pair of cooling wall portions to be deformed closer to each other by elastic deformation.

[0047] In a cooling heat exchanger constructed according to this aspect, for example, when a battery, which is the object to be cooled, swells and deforms due to heating caused by charging and discharging, the pair of cooling walls are allowed to deform toward each other in response to the swelling and deformation of the battery by the elastic deformation of the elastic deformation portions of the inner fins arranged between the opposing surfaces of the pair of cooling walls. Therefore, even in a structure in which inner fins are arranged between the opposing surfaces of the pair of cooling walls, problems such as the overlapping surfaces of the cooled object and the cooled surface separating due to deformation of the cooled object are prevented by the cooling walls deforming to conform to the surface shape of the cooled object, and stable cooling performance is demonstrated.

[0048] In a sixteenth aspect, in the cooling heat exchanger described in any one of the first to fifteenth aspects, the first protrusions and the second protrusions each extend across the entire flow path width of the cooling flow path and are continuous with the side wall portions of the cooling flow path at both ends.

[0049] In a cooling heat exchanger constructed according to this aspect, the flow of the heat medium between the side wall of the cooling flow passage and the first and second protrusions can be prevented from bypassing the first and second protrusions, thereby efficiently improving cooling performance. Furthermore, if the first and second protrusions are spaced apart from the side wall of the cooling flow passage, the flow rate of the heat medium flowing between the side wall of the cooling flow passage and the first and second protrusions tends to increase, which may result in wear on the wall of the cooling flow passage and the first and second protrusions. However, in the cooling heat exchanger according to this aspect, the first and second protrusions extend across the entire width of the flow passage and are continuous with the side wall of the cooling flow passage, thereby preventing the heat medium from flowing between the side wall of the cooling flow passage and the first and second protrusions, thereby preventing wear on the wall of the cooling flow passage and the first and second protrusions.

[0050] In a seventeenth aspect, in the cooling heat exchanger described in any one of the first to sixteenth aspects, the protrusion height of at least one of the first protrusions and the second protrusions varies in the flow path width direction of the cooling flow path, and either a low protrusion with a low protrusion height or a high protrusion with a high protrusion height is located in the central portion in the flow path width direction, and either the low protrusion or the high protrusion is located at both end portions of the first protrusion and the second protrusion in the flow path width direction.

[0051] In a cooling heat exchanger constructed according to this aspect, the flow of heat medium that flows over the central portion of the protrusions in the flow path width direction can be made different in stirring effect, flow rate, etc. from the flow of heat medium that flows over the both end portions of the first protrusions and / or second protrusions in the flow path width direction. Therefore, the influence of the first protrusions and / or second protrusions on cooling performance can be made different between the central portion and both end portions in the flow path width direction, and cooling performance can be adjusted in the flow path width direction.

[0052] In an eighteenth aspect, in the cooling heat exchanger described in the seventeenth aspect, at least one of the multiple first protrusions and the multiple second protrusions arranged side by side in the flow path length direction of the cooling flow path is configured so that a central low protrusion in which the low protrusion is set in the central part of the flow path width direction of the cooling flow path and the high protrusions are set at both end parts, and a central high protrusion in which the high protrusion is set in the central part of the flow path width direction of the cooling flow path and the low protrusions are set at both end parts, are arranged alternately in the flow path length direction of the cooling flow path.

[0053] In a cooling heat exchanger constructed according to this aspect, central low protrusions, each having a low protrusion set in the center of the flow path width direction, and central high protrusions, each having low protrusions set at both ends of the flow path width direction, are alternately arranged in the flow path length direction, so that, for example, the flow of the heat medium connecting the low protrusions, which tend to have low flow resistance, snakes in the flow path width direction, thereby exerting the effect of stirring the heat medium in the flow path width direction. Furthermore, for example, by having the heat medium pass through the low protrusion of one protrusion and flow toward the high protrusion of the next protrusion, it can be expected that the heat medium that passes through the low protrusion smoothly with relatively low flow resistance will collide with the high protrusion and be efficiently stirred.

[0054] In a nineteenth aspect, in the cooling heat exchanger described in any one of the first to eighteenth aspects, at least one of the first protrusions and the second protrusions has a cross-sectional shape that tapers toward the protrusion tip in a cross section of the cooling flow path in the flow path length direction, and an arc-shaped protrusion apex, an upstream inclined portion extending at an angle from the protrusion apex toward the upstream side of the cooling flow path toward the protrusion base which is the bottom side of the cooling flow path, and a downstream inclined portion extending at an angle from the protrusion apex toward the downstream side toward the protrusion base are provided smoothly and continuously without corners.

[0055] In a cooling heat exchanger constructed according to this aspect, the surfaces of the protrusions are smoothly continuous in the cross section in the longitudinal direction of the flow passage, so that the heat medium flows smoothly over the protrusions.

[0056] In a twentieth aspect, in the cooling heat exchanger described in the nineteenth aspect, in a cross section of the cooling flow path in the flow path length direction, the radius of curvature of the protrusion top is within a range of 0.05 to 1.5 times the length dimension of the protrusion base, and in a cross section of the cooling flow path in the flow path length direction, the inclination angle of the upstream inclined portion with respect to the bottom surface of the cooling flow path is within a range of 20 to 70 degrees.

[0057] In a cooling heat exchanger constructed according to this aspect, the radius of curvature of the projection apex is 0.05 times or more the length of the projection base, so that the projection apex has a smooth arc-shaped cross section without being substantially angular. Also, the radius of curvature of the projection apex is 1.5 times or less the length of the projection base, so that the length of the projection in the flow path direction is prevented from becoming excessively long, and the inclination angle of the upstream inclined portion and the downstream inclined portion, which are smoothly continuous with the projection apex, relative to the bottom surface can be set sufficiently large.

[0058] By setting the inclination angle of the upstream inclined portion relative to the bottom surface of the cooling channel to 20° or more, the flow of the heat transfer medium from the upstream side toward the protrusions is effectively disturbed by the upstream inclined portion, improving cooling performance through a stirring effect. Also, by setting the inclination angle of the upstream inclined portion relative to the bottom surface of the cooling channel to 70° or less, the flow of the heat transfer medium can be prevented from being excessively restricted by the protrusions.

[0059] A twenty-first aspect is a cooling heat exchanger according to the nineteenth aspect, wherein, in a cross section of the cooling flow path in the flow path length direction, the inclination angle of the upstream inclined portion relative to the bottom surface of the cooling flow path is 25° or less.

[0060] In the cooling heat exchanger constructed according to this embodiment, the inclination angle of the upstream inclined portion relative to the bottom surface of the cooling flow path is set to 25° or less, so that the pressure loss can be set sufficiently small, and it becomes possible to circulate the heat transfer medium using, for example, a less expensive pump with lower performance.

[0061] In a twenty-second aspect, in a cooling heat exchanger described in any one of the first to twenty-first aspects, at least one of the first protrusions and the second protrusions aligned in the cooling flow path in the flow path length direction has a protrusion height that decreases downstream.

[0062] In a cooling heat exchanger constructed according to this aspect, the protrusion height of the first protrusions and / or the second protrusions aligned in the flow path length direction increases toward the downstream side, so that the protrusions can more effectively disrupt the flow of the heat medium downstream, thereby more effectively improving the cooling performance of the protrusions downstream, where the heat medium flowing near the object to be cooled is likely to become hot due to heat exchange.

[0063] In a twenty-third aspect, in the cooling heat exchanger described in any one of the first to twenty-second aspects, at least one of the first protrusions and the second protrusions aligned in the cooling flow path in the flow path length direction has a spacing in the flow path length direction of the cooling flow path that narrows downstream.

[0064] In a cooling heat exchanger constructed according to this aspect, the spacing between the first and / or second protrusions arranged in the flow path length direction is narrowed toward the downstream side, so that the protrusions can exert a stronger effect of disrupting the flow of the heat medium downstream, thereby more effectively improving the cooling performance of the protrusions downstream, where the temperature is likely to increase due to heat exchange with the object to be cooled.

[0065] In a twenty-fourth aspect, in the cooling heat exchanger described in any one of the first to twenty-third aspects, at least one of the first protrusions and the second protrusions aligned in the cooling flow path in the flow path length direction has a protrusion height that decreases toward downstream, and the spacing between the first protrusions and the second protrusions in the flow path length direction of the cooling flow path becomes narrower toward downstream.

[0066] In a cooling heat exchanger constructed according to this aspect, the height of the protrusions increases and the spacing (pitch) between the protrusions decreases toward the downstream side, so that the protrusions exert a stronger stirring effect on the flow of the heat medium toward the downstream side, thereby more effectively suppressing a decrease in cooling performance downstream.

[0067] According to the present invention, in a cooling heat exchanger, a double-sided cooling structure having cooling surfaces on both sides can be realized with a simple structure, while excellent cooling performance can be stably obtained.

[0068] 3 is an exploded perspective view showing a cooling heat exchanger according to a first embodiment of the present invention; FIG. 4 is a cross-sectional view of the cooling heat exchanger shown in FIG. 1, corresponding to the II-II cross section of FIG. 3; FIG. 5 is a cross-sectional view of the cooling heat exchanger according to the third embodiment of the present invention; FIG. 6 is a plan view of an inner fin constituting the cooling heat exchanger shown in FIG. 1; FIG. 7 is an enlarged view of the V-V cross section of FIG. 4; 10 is a cross-sectional view of the inner fin shown in FIG. 10, showing an enlarged view of a portion of the XIII-XIII cross section of FIG. 11; an enlarged cross-sectional view corresponding to the XII-XII cross section of FIG. 10; an enlarged cross-sectional view corresponding to the XIII-XIII cross section of FIG. 10; a plan view of an inner fin constituting a cooling heat exchanger according to a sixth embodiment of the present invention; an enlarged cross-sectional view corresponding to the XV-XV cross section of FIG. 14; an enlarged cross-sectional view corresponding to the XVI-XVI cross section of FIG. 14; a cross-sectional view showing a portion of an inner fin constituting a cooling heat exchanger according to a seventh embodiment of the present invention; and a cross-sectional view showing a portion of an inner fin constituting a cooling heat exchanger according to another embodiment of the present invention.

[0069] Hereinafter, an embodiment of the present invention will be described with reference to the drawings.

[0070] 1 to 3 show a cooling heat exchanger 10 according to a first embodiment of the present invention. As shown in FIGS. 2 and 3 , the cooling heat exchanger 10 includes a hollow outer wall member 12, which is composed of a first member 14 and a second member 16. In the following description, the vertical direction generally refers to the vertical direction in FIG. 2 , the left-right direction generally refers to the left-right direction in FIG. 2 , and the front-rear direction generally refers to the left-right direction in FIG. 3 . The vertical, left-right, and front-rear directions are merely used for convenience of explanation. Therefore, for example, the vertical direction of the cooling heat exchanger 10 in use may be the vertical direction in the above-described embodiment, the left-right direction, or the front-rear direction, or it may be a direction that does not coincide with any of the vertical, left-right, or front-rear directions.

[0071] The first member 14 has a generally rectangular flat plate shape, with its length in the left-right direction being greater than its width in the front-rear direction. The first member 14 is preferably formed from a material with high thermal conductivity, such as an aluminum alloy, stainless steel, or copper alloy. The first member 14 may also be a clad plate, for example, in which a brazing filler metal is laminated on a base material. When the first member 14 is a clad plate, for example, the base material may be formed from an Al-Mn-based aluminum alloy in which manganese is added to aluminum, and the brazing filler metal may be formed from an Al-Si-based aluminum alloy in which silicon is added to aluminum. The first member 14 may also be a clad plate, for example, in which a stainless steel base material is combined with a nickel alloy brazing filler metal. Clad plates can be obtained by known manufacturing methods, such as pressure bonding the base material to the brazing filler metal or spraying the brazing filler metal onto the base material.

[0072] The second member 16 is an open rectangular box having a recess 18 that opens downward, and integrally includes a substantially rectangular flat upper bottom wall and a rectangular cylindrical peripheral wall that protrudes downward from the outer peripheral edge of the upper bottom wall. The second member 16 is preferably made of a material with high thermal conductivity, similar to the first member 14, such as an aluminum alloy, stainless steel, or copper alloy.

[0073] A supply hole 20 is formed in the left end portion of the second member 16, vertically penetrating the upper bottom wall of the recess 18, and a discharge hole 22 is formed in the right end portion of the second member 16, vertically penetrating the upper bottom wall of the recess 18. The second member 16 is provided with a substantially cylindrical supply port 24 that protrudes upward from the upper bottom wall of the recess 18 at the periphery of the opening of the supply hole 20, and a substantially cylindrical discharge port 26 that protrudes upward from the upper bottom wall of the recess 18 at the periphery of the opening of the discharge hole 22.

[0074] 2 and 3, the first member 14 and the second member 16 are stacked and fixed to each other in the vertical direction. The protruding tip surface of the peripheral wall of the recess 18 in the second member 16 abuts against the outer peripheral end of the first member 14, and the first member 14 and the second member 16 are fixed to each other by brazing with a brazing filler metal of the first member 14, which may be a clad plate, for example. By stacking and fixing the first member 14 and the second member 16 to each other in this way, the outer wall member 12 is formed by the first member 14 and the second member 16.

[0075] The opening of the recess 18 of the second member 16 is covered with the first member 14, thereby forming a cooling flow path 28 inside the outer wall member 12. The cooling flow path 28 is a flow path through which a heat transfer medium, for example, a liquid such as water or an ethylene glycol aqueous solution, or a gas such as air, flows. A low-temperature heat transfer medium is supplied to the cooling flow path 28 from the outside through the supply hole 20, and the heat transfer medium heated by heat exchange is discharged to the outside through the discharge hole 22. Therefore, the supply hole 20 is provided at the upstream end of the cooling flow path 28, and the discharge hole 22 is provided at the downstream end of the cooling flow path 28. Note that, since the cooling flow path 28 through which the heat transfer medium flows is formed inside the outer wall member 12, the joint between the first member 14 and the second member 16 is fluid-tight, preventing leakage of the heat transfer medium.

[0076] The outer wall member 12 is provided with a pair of cooling wall portions 30, 30. That is, the portion of the first member 14 that forms the wall portion of the cooling flow path 28 is the lower cooling wall portion 30. Furthermore, the bottom wall of the recess 18 in the second member 16 is the upper cooling wall portion 30. Therefore, the portions of the outer wall member 12 that face each other in the up-down direction are the pair of cooling wall portions 30, 30. The cooling wall portions 30, 30 are cooled by heat exchange with the heat medium flowing through the cooling flow path 28. The upper and lower outer surfaces of the cooling wall portions 30, 30 are flat surfaces that extend approximately perpendicular to the up-down direction, and each of these upper and lower outer surfaces is a cooling surface 32.

[0077] An inner fin 34 is housed in the cooling flow passage 28 formed between the opposing surfaces of the first member 14 and the bottom wall of the recess 18 in the second member 16. As shown in FIGS. 4 and 5 , the inner fin 34 has a generally rectangular plate shape with an overall left-to-right length greater than its front-to-back width. The inner fin 34 is formed of, for example, a metal such as an aluminum alloy or stainless steel, or a synthetic resin. In this embodiment, the inner fin 34 is a pressed metal piece made of an aluminum alloy. The inner fin 34 is preferably made of a material with high thermal conductivity, similar to the first and second members 14 and 16. The inner fin 34 has a shape and size that allows it to be inserted into the recess 18 of the second member 16.

[0078] An end wall portion 35 protruding in the vertical direction is provided at each end of the inner fin 34 in the front-to-rear direction. The end wall portion 35 protrudes upward, then bends downward at the end, and protrudes downward again, thereby protruding on both the top and bottom sides. More specifically, the end wall portion 35 integrally includes an end wall connecting portion 36 protruding upward and an end wall main portion 37 that bends downward from the upper end of the end wall connecting portion 36. The end wall connecting portion 36 is inclined in a direction away from the end wall main portion 37 in the front-to-rear direction. The end wall main portion 37 is substantially non-inclined in the vertical direction. The end wall main portion 37 extends further downward than the lower end of the end wall connecting portion 36. Note that the end wall portion 35 may be configured such that the end wall connecting portion 36 protrudes downward and the end wall main portion 37 extends upward from the lower end of the end wall connecting portion 36.

[0079] An intermediate partition 38 is provided between the end wall portions 35, 35 of the inner fin 34. The intermediate partition 38 is integrally continuous with the end wall connecting portion 36 at the inner end portion in the front-to-rear direction. The end wall portion 35 protrudes on both sides in the vertical direction relative to the intermediate partition 38. The intermediate partition 38 is located midway between the end wall main body portion 37 in the vertical direction and extends in a direction approximately perpendicular to the vertical direction. In this embodiment, the intermediate partition 38 is divided into three protrusion-forming portions 40, 40, 40 by two partition walls 42, 42, which will be described later.

[0080] Two partition walls 42, 42 are provided in the inner fin 34 midway between the intermediate partition 38 in the front-rear direction, protruding from the intermediate partition 38 on both sides in the up-down direction. The partition wall 42 integrally includes a partition main body 44 protruding from both sides in the up-down direction relative to the intermediate partition 38, and a pair of partition connectors 46, 46 connecting the upper and lower ends of the partition main body 44 to the intermediate partition 38. The partition main body 44 is formed continuously over the entire length of the inner fin 34 in the left-right direction and is generally not inclined in the up-down direction. The partition connectors 46 are formed continuously over the entire length of the inner fin 34 in the left-right direction and extend inward in the up-down direction from both upper and lower ends of the partition main body 44. The partition connectors 46 are inclined in a direction away from the partition main body 44 in the front-rear direction. The partition connecting portions 46, 46 extending from both the upper and lower ends of the partition main body portion 44 are connected to each of two adjacent protrusion forming portions 40, 40 in the front-to-rear direction, and these two protrusion forming portions 40, 40 are integrally connected by the partition portion 42.

[0081] Each of the protrusion-forming portions 40, 40, 40 of the intermediate partition portion 38, which are separated by the partition walls 42, 42, has a plurality of protrusions 48. As shown in FIG. 4 , the protrusions 48 are generally V-shaped on the surface of the inner fin 34, and are generally V-shaped in a vertical view. When the inner fin 34 is disposed in the cooling flow passage 28 (described later), the protrusions 48 narrow in the front-to-rear direction toward the left, which is the upstream side of the cooling flow passage 28. The left side of the protrusion 48, which is the upstream side of the cooling flow passage 28, forms an upstream inclined surface 50 as an upstream inclined portion that is inclined so that the protrusion height increases toward the downstream side, and the right side of the protrusion 48 forms a downstream inclined surface 52 as a downstream inclined portion that is inclined so that the protrusion height decreases toward the downstream side. As a result, a ridge 54 with the maximum protrusion height is formed in a generally V-shaped manner in a vertical view at the left-to-right center of the protrusion 48, which is the connecting portion between the upstream inclined surface 50 and the downstream inclined surface 52.

[0082] The protrusions 48 are provided in a plurality, spaced at approximately equal intervals in the left-right direction. The protrusion-forming portions 40, 40, 40 have the same number of first protrusions 48a (described below) formed at approximately the same positions relative to each other in the left-right direction. The same number of second protrusions 48b (described below) formed at approximately the same positions relative to each other in the left-right direction. The protrusions 48 are provided over approximately the entire length of the intermediate partition portion 38 in the left-right direction. The protrusions 48 are scattered over approximately the entire area of ​​the protrusion-forming portion 40 in the front-rear direction. However, in this embodiment, the protrusions 48 are slightly spaced apart from the end wall portions 35, 35 and the partition wall portions 42, 42 in the front-rear direction, and there are portions at the front and rear ends of the protrusion-forming portion 40 that are free of protrusions 48. This prevents the protrusions 48 from interfering with the molding of the end wall portions 35, 35 and the partition wall portions 42, 42 when the end wall portions 35, 35 and the partition wall portions 42, 42 are formed by press working. The protrusion 48 may be provided continuously across the entire width (front-rear direction) of the protrusion forming portion 40 , with both ends directly connected to the partition wall portion 42 and / or the end wall portion 35 .

[0083] As shown in Figures 2 and 5, the protrusions 48 include first protrusions 48a that protrude from the lower surface of the intermediate partition portion 38 and second protrusions 48b that protrude from the upper surface of the intermediate partition portion 38. As shown in Figure 2, the first protrusions 48a and the second protrusions 48b are arranged alternately in the left-right direction. In this embodiment, the first protrusions 48a and the second protrusions 48b have approximately the same shape and size and protrude in opposite directions, but they may have different shapes and sizes. In this embodiment, the left-right arrangements of the first protrusions 48a and the second protrusions 48b on the three protrusion forming portions 40, 40, 40 are the same, but they may be different.

[0084] As shown in FIGS. 1 to 3 , the inner fin 34 is disposed between the first member 14 and the second member 16, and as shown in FIGS. 2 and 3 , the inner fin 34 is housed in the cooling flow passage 28 that constitutes the interior region of the outer wall member 12. The left-right length of the inner fin 34 is smaller than the left-right length of the cooling flow passage 28, and both left and right end surfaces of the inner fin 34 are spaced laterally inward from the outer wall member 12. In other words, the inner fin 34 is disposed partially in the length direction of the cooling flow passage 28 and is located approximately at the center of the cooling flow passage 28. Therefore, in this embodiment, the interior region of the outer wall member 12 divided in two by the inner fin 34 is, more specifically, the central portion in the left-right direction of the cooling flow passage 28, excluding both left-right end portions. In this embodiment, the inner fin 34 is located laterally inward of the supply holes 20 and discharge holes 22 formed at both end portions of the cooling flow passage 28 in the length direction, and is disposed without covering the supply holes 20 and discharge holes 22.

[0085] The inner fin 34 may be positioned relative to the outer wall member 12 by fitting the end wall portions 35, 35 against the side walls of the second member 16 in the front-to-rear direction, or by sandwiching at least one of the end wall portions 35, 35 and the partition portions 42, 42 between the bottom walls of the first member 14 and the second member 16. Note that a positioning structure other than the end wall portions 35, 35 and the partition portions 42, 42 may be provided between the inner fin 34 and the outer wall member 12. Specifically, for example, by providing a protrusion on at least one of the bottom wall and side wall of the second member 16 that engages with the left and right end surfaces of the inner fin 34 in the left-to-right direction, the inner fin 34 can be positioned relative to the outer wall member 12 in the front-to-rear, left-to-right, and up-to-down directions without having to fit the end wall portions 35, 35 into the recesses 18 or sandwich the end wall portions 35, 35 and / or the partition portions 42, 42 between the first and second members 14, 16. In addition, the inner fin 34 may be unattached to the outer wall member 12, or, for example, at least one of the end wall portions 35, 35 and the partition portions 42, 42 may be fixed to the outer wall member 12 by means of adhesion, brazing, etc.

[0086] By disposing the inner fins 34 in the cooling flow passage 28, the cooling flow passage 28 is divided into multiple sections by the inner fins 34 in the intermediate portion in the flow passage length direction. That is, the intermediate partition portion 38 of the inner fin 34 is located midway between the end wall portions 35, 35 and the partition wall portions 42, 42 in the up-down direction, and is therefore separated from both the cooling wall portions 30, 30. As a result, the cooling flow passage 28 is divided into two, upper and lower, by the inner fin 34, and the region of the cooling flow passage 28 below the inner fin 34 is used as a region for cooling the cooling wall portion 30 of the first member 14, and the region above the inner fin 34 is used as a region for cooling the cooling wall portion 30 of the second member 16.

[0087] Since the cooling flow path 28 is divided into two halves, upper and lower, by the intermediate partition 38 of the inner fin 34, in a cooling heat exchanger 10 with a double-sided cooling structure in which cooling surfaces 32 are provided on both the upper and lower surfaces, it becomes easy to control the flow rate and flow velocity of the heat medium by adjusting the flow path cross-sectional area of ​​the upper and lower regions of the cooling flow path 28 that cools the cooling surfaces 32, 32 (cooling wall portions 30, 30).

[0088] Since the inner fins 34 are disposed in the middle of the cooling flow passage 28 in the flow passage length direction, both ends of the cooling flow passage 28 in the flow passage length direction, where the supply holes 20 and the discharge holes 22 are provided, are not divided into upper and lower sections by the inner fins 34. Therefore, the heat medium supplied from the supply holes 20 to the cooling flow passage 28 flows into both the upper and lower regions of the cooling flow passage 28 without being obstructed by the inner fins 34, and the heat medium that has passed through both the upper and lower regions of the cooling flow passage 28 is also discharged to the outside from the discharge holes 22 without being obstructed by the inner fins 34.

[0089] The regions of the cooling flow path 28 on both the upper and lower sides of the inner fin 34 are divided into three sections in the front-to-rear direction by two partition walls 42. As a result, the cooling flow path 28 is divided into six flow path sections 56, 56..., 56 in which the heat medium flows in the same direction, and these six flow path sections 56, 56..., 56 arranged in parallel form a parallel flow path section 58 of this embodiment.

[0090] In this way, the upper and lower regions of the cooling flow path 28 are divided into three sections each in the flow path width direction by the partition sections 42, 42, so that the flow rate and flow speed of the heat transfer medium flowing through each flow path section 56 can be appropriately controlled, while the size in the flow path width direction of the cooling surfaces 32, 32 on which the cooling action is exerted by those flow path sections 56 can be set with greater freedom.

[0091] As shown in FIGS. 2 and 3 , either the first protrusion 48a or the second protrusion 48b protrudes from the intermediate partition portion 38 of the inner fin 34 into each flow passage portion 56. The first protrusion 48a is spaced upward relative to the lower cooling wall portion 30. A first narrowed flow passage 60a, whose flow passage cross-sectional area is smaller than that of the remaining portions, is formed between the first protrusion 48a and the lower cooling wall portion 30 in the lower flow passage portion 56. The second protrusion 48b is spaced downward relative to the upper cooling wall portion 30. A second narrowed flow passage 60b, whose flow passage cross-sectional area is smaller than that of the remaining portions, is formed between the second protrusion 48b and the upper cooling wall portion 30 in the upper flow passage portion 56. In this embodiment, the first narrowed flow passage 60a and the second narrowed flow passage 60b have substantially the same flow passage cross-sectional area and flow passage cross-sectional shape, but they may be different from each other.

[0092] As shown in FIG. 6 , the cooling heat exchanger 10 having such a structure is equipped with a battery pack 62 as a cooling target. The battery pack 62 is a battery used in an electrically powered vehicle such as an electric vehicle or a hybrid car. The battery pack 62 has, for example, a generally rectangular parallelepiped shape with a front-to-rear width dimension greater than a left-to-right length dimension. Furthermore, terminals 64 protruding forward are provided at both upper and lower ends of the battery pack 62. The terminals 64 serve as output terminals for outputting a large current through a bus bar (not shown). Therefore, in use, the upper and lower end portions of the battery pack 62, which include the terminals 64, tend to become hotter than the upper and lower central portions.

[0093] The cooling heat exchanger 10 has a double-sided cooling structure in which cooling surfaces 32 are provided on both the top and bottom surfaces, and the battery packs 62 are respectively superimposed on the cooling surfaces 32, 32 on both the top and bottom of the cooling heat exchanger 10. In this embodiment, a plurality of battery packs 62 are arranged side by side in the left-right direction, which is the flow path length direction of the cooling flow path 28, on both the top and bottom of the cooling heat exchanger 10, and the plurality of battery packs 62 are superimposed on the cooling surfaces 32, 32.

[0094] In the cooling heat exchanger 10, cooling surfaces 32, 32 set on the surfaces of the cooling walls 30, 30 are cooled by heat exchange between the cooling heat medium flowing through the cooling flow passage 28 and the cooling wall portions 30, 30 of the first and second members 14, 16. A battery pack 62 that generates heat during operation is set on the cooling surfaces 32, 32, and the battery pack 62 is cooled by heat exchange between the first and second members 14, 16 having the cooling surfaces 32, 32 and the battery pack 62 placed on each cooling surface 32. In other words, the battery pack 62 is cooled by heat exchange between the battery pack 62 and the heat medium flowing through the cooling flow passage 28 via the first and second members 14, 16.

[0095] Inner fins 34 are arranged in the cooling flow passages 28, and the inner fins 34 are in contact with the outer wall member 12 (first and second members 14, 16). Therefore, the inner fins 34 increase the substantial contact area between the outer wall member 12 and the heat medium, and the cooling surfaces 32, 32 are efficiently cooled by the heat medium.

[0096] The temperature of the heat medium rises as it receives heat from the battery pack 62. In particular, the heat medium flowing near the cooling walls 30 is heated by the heat of the battery pack 62 and becomes hotter. On the other hand, the heat medium flowing far from the cooling walls 30, in other words, near the inner fins 34, is less affected by the heat of the battery pack 62, and therefore the temperature rise is relatively suppressed and the heat medium is likely to be maintained at a low temperature. As a result, a temperature distribution in which the temperature of the heat medium in the cooling flow path 28 increases toward both the top and bottom due to heat exchange with the battery pack 62 is likely to occur. As a result, the temperature difference between the high-temperature heat medium flowing near the cooling walls 30 and the battery pack 62 becomes smaller, resulting in a decrease in the efficiency of heat exchange between the battery pack 62 and the heat medium.

[0097] Therefore, in the cooling heat exchanger 10, the inner fins 34 are provided with first and second protrusions 48a, 48b that protrude into the cooling flow path 28, and the heat medium is agitated when it passes over the first and second protrusions 48a, 48b, thereby reducing the temperature difference in the vertical direction of the heat medium. This prevents only the heat medium flowing near the battery pack 62 from becoming hot, and ensures a large temperature difference between the battery pack 62 and the heat medium flowing nearby, thereby improving the heat exchange efficiency between the battery pack 62 and the heat medium.

[0098] In this embodiment, the first and second protrusions 48a, 48b are formed over substantially the entire width of the inner fin 34 in the left-right direction. As a result, the first and second protrusions 48a, 48b agitate the heat medium in the parallel flow path section 58 formed by the inner fin 34, and the battery packs 62 are efficiently cooled by the heat medium flowing through the parallel flow path section 58. Note that in the cooling heat exchanger 10 of this embodiment, the inner fins 34 are provided outward on both sides in the left-right direction beyond the area where the battery packs 62 are overlapped, so that the effect of the inner fins 34 in improving heat exchange efficiency is effectively applied to all of the battery packs 62.

[0099] In this embodiment, the protrusions 48 are V-shaped on the surface of the inner fin 34, narrowing toward the upstream side of the flow path 56. In other words, the protrusions 48 are V-shaped in a plan view. When the heat medium passes over the protrusions 48, it attempts to flow in a direction perpendicular to the protrusions 48, where flow resistance is reduced, and therefore flows in a direction inclined inward in the flow path width direction with respect to the flow path length direction (left-right direction) of the flow path 56. The heat medium flows inward in the flow path width direction merge downstream of the protrusions 48, generating vortices and turbulence downstream of the protrusions 48, which agitate the heat medium. This reduces the temperature difference between the heat medium in the vertical direction and suppresses a decrease in cooling performance due to the heat medium being heated by the battery pack 62.

[0100] The battery pack 62 may deform so that its surface bulges due to heat generation during use. In such a case, the cooling wall portions 30, 30 including the cooling surfaces 32, 32 are elastically deformable to follow the deformation of the battery pack 62. That is, the flat cooling wall portions 30, 30 are allowed to elastically flex and deform, and the partition portions 42 of the inner fins 34, which are overlaid on the cooling wall portions 30 from the cooling flow path 28 side, are allowed to elastically flex and deform at at least one of the partition main body portions 44 and the partition connecting portions 46, 46. As a result, when the surface of the battery pack 62 bulges and deforms toward the cooling surface 32 and the cooling surface 32 is pressed toward the cooling flow path 28, the elastic flex and deformation of the cooling wall portions 30 including the cooling surface 32 occurs without being hindered by the partition portions 42 of the inner fins 34. In this way, the cooling surface 32 elastically deforms in response to deformation of the surface of the battery pack 62, thereby preventing gaps from occurring between the overlapping surfaces of the cooling surface 32 and the battery pack 62, plastic deformation of the first and second members 14, 16 having the cooling wall portions 30, 30, and plastic deformation of the inner fins 34. As can be seen from the above, in the inner fin 34 of this embodiment, the partition portions 42, 42 are elastically deforming portions that allow the cooling wall portions 30, 30 to approach each other (approaching deformation) due to elastic deformation.

[0101] Because the partition walls 42 are allowed to elastically flex and deform, even if the vertical height of the partition walls 42 is slightly greater than the depth of the recess 18 due to an error, the partition walls 42 can elastically flex and deform to accommodate the partition walls 42 within the cooling flow path 28. In this embodiment, the end wall portions 35 of the inner fin 34 are also allowed to elastically flex and deform in the same way as the partition walls 42, so that the end wall portions 35 are also prevented from being improperly accommodated within the cooling flow path 28. Therefore, it is possible to employ a structure in which the inner fin 34 is sandwiched and supported between the cooling wall portions 30 while allowing for dimensional differences due to tolerances of the second member 16 and the inner fin 34.

[0102] 7 shows a cooling heat exchanger 70 according to a second embodiment of the present invention. The cooling heat exchanger 70 has a structure in which inner fins 72 are disposed between the first member 14 and the second member 16. In the following description, components and parts that are substantially the same as those in the previous embodiment are denoted by the same reference numerals in the drawings, and description thereof will be omitted.

[0103] The inner fin 72 is formed of a metal, a synthetic resin, or the like, and has a thin plate shape. The inner fin 72 has a cross section that is folded back in a zigzag or wave shape in the up-down direction. In this embodiment, a plurality of flat inclined plate portions 74 that extend at an angle in the up-down direction and the front-rear direction are provided so as to be integrally connected in the front-rear direction at the apexes 76 of the folds, forming a zigzag cross section. The inner fin 72 has a zigzag cross section that extends linearly in the left-right direction. Note that the number of folds (the number of apexes 76) of the zigzag or wave-shaped inner fin 72 is not particularly limited and can be appropriately set taking into consideration, for example, the width of the cooling surface and the cross-sectional area of ​​the flow passage portion defined by the inner fin 72.

[0104] The inner fin 72 is formed with protrusions 78. The protrusions 78 are generally V-shaped on the surface of the inner fin 72 and taper (narrow) toward the upstream side of the cooling flow path. In other words, the protrusions 78 are generally V-shaped when viewed from the top. The protrusions 78 are composed of first protrusions 78a protruding from the upper surface of the inner fin 72 and second protrusions 78b protruding from the lower surface of the inner fin 72. The first protrusions 78a and the second protrusions 78b are arranged in pairs spaced apart from each other in the left-right direction, which is the flow path length direction of the cooling flow path. In this embodiment, the first protrusions 78a and the second protrusions 78b are arranged in two rows in the front-rear direction, which is the flow path width direction of the cooling flow path, with five pairs in each row. Therefore, the inner fin 72 of this embodiment has ten first protrusions 78a and ten second protrusions 78b.

[0105] The V-shaped protrusions 78 are formed so that their narrower upstream ends are positioned at the zigzag crests 76 of the inner fin 72, which are the connecting portions of the swash plate portions 74, 74. The downstream ends of the V-shaped protrusions 78 do not reach the ends of the swash plate portion 74, and adjacent protrusions 78, 78 in the fore-aft direction are spaced apart from each other in the fore-aft direction. The protrusions 78 may be provided so as to reach the crests 76, or may be provided at a portion outside the crests 76. It is sufficient that the protrusions 78 are provided on at least the swash plate portion 74 between adjacent crests 76, 76. However, it is preferable that the protrusions 78 are also provided on the swash plate portion 74 between the fore-aft end of the inner fin 72 and the adjacent crest 76.

[0106] In this embodiment, the inner fins 72 are formed as pressed metal fittings, and the protrusions 78 are formed by press working, so that there are V-shaped recesses on the surface opposite to the protruding side of the protrusions 78. Note that if the protrusions 78 are formed at the same time as a flat metal plate is formed into a zigzag cross section by press working, the number of processing steps can be reduced.

[0107] In the cooling heat exchanger 70 equipped with such inner fins 72, the cooling flow passage (not shown) formed between the first member 14 and the second member 16 is divided in the up-down direction, which is the flow passage height direction, by the inner fins 72. Moreover, because the inner fins 72 have a cross-sectional shape folded back in a zigzag pattern, the apexes 76 of the folds are overlapped with the first member 14 or the second member 16, thereby dividing the cooling flow passage into multiple sections in the front-to-rear direction, which is the flow passage width direction. As a result, the cooling surfaces 32 provided on the upper and lower outer surfaces of the first member 14 and the second member 16 are each effectively cooled by the flow passage portions of the divided cooling flow passages.

[0108] The inner fin 72 of this embodiment has a simpler shape than the inner fin 34 of the first embodiment, and can divide the cooling flow passage not only into upper and lower sections but also in the width direction of the flow passage, thereby improving cooling performance. The inner fin 72 may be disposed between the first member 14 and the second member 16 without being fixed thereto, or the top portion 76 and both front and rear end portions may be fixed to the first and second members 14, 16.

[0109] Furthermore, since the inner fin 72 is provided with first and second protrusions 78a, 78b that protrude into the flow path region of the cooling flow path, the heat medium flowing through these flow path regions is stirred by the first and second protrusions 78a, 78b, preventing only the heat medium flowing near each cooling surface 32 from becoming hot, thereby improving cooling performance.

[0110] When the cooling wall sections 30, 30 are deformed toward each other due to, for example, the action of pressing force from the battery pack, the inner fins 72 can allow the deformation of the cooling wall sections 30, 30 by elastically bending and deforming the swash plate sections 74. In this way, the swash plate sections 74 function as elastic deformation sections, which improves the ability of the cooling surfaces 32 provided on the cooling wall sections 30, 30 to follow the battery pack and prevents unintended plastic deformation due to external input.

[0111] Although Figure 7 illustrates an inner fin 72 having a zigzag cross section, it is also possible to use an inner fin having a wavy cross section in which the entire cross section is curved without having a flat inclined plate portion 74.

[0112] 8 shows a cooling heat exchanger 80 according to a third embodiment of the present invention. The cooling heat exchanger 80 has a structure in which inner fins 82 are disposed between the first member 14 and the second member 16.

[0113] The inner fin 82 is a plate-like member having a zigzag or wavy cross section, similar to the inner fin 72 of the second embodiment. The inner fin 82 differs from the inner fin 72 of the second embodiment in the size of the protrusions 84 (first protrusions 84a and second protrusions 84b). The protrusions 84 of this embodiment are V-shaped, similar to the protrusions 78 of the second embodiment, and are provided continuously over the entire fore-and-aft direction of the swash plate portion 74, with their downstream ends reaching the fore-and-aft ends of the swash plate portion 74.

[0114] As shown in this embodiment, the protrusions 84 may be formed over substantially the entire inner fin 82 in the flow path width direction of the cooling flow path. The protrusions 84 may be provided up to the apex 76 of the folded portion of the inner fin 82, but are preferably provided in a portion outside the apex 76 to facilitate processing.

[0115] 9 shows an inner fin 90 constituting a cooling heat exchanger according to a fourth embodiment of the present invention. Since the inner fin 90 of this embodiment can be used in place of the inner fin 34 of the first embodiment, in the following description, the same reference numerals as in the first embodiment will be used to designate components and parts that are substantially the same as those in the first embodiment for ease of understanding.

[0116] A plurality of protrusions 48 (first protrusions 48a and second protrusions 48b) are formed on the intermediate partition portion 38 (protrusion-forming portions 40, 40, 40) of the inner fin 90. In this embodiment, the protrusions 48 are not provided on the left portion of the inner fin 90 located on the upstream side of the cooling flow passage 28, but are provided only on the right portion of the inner fin 90 located on the downstream side of the cooling flow passage 28. As a result, the effect of the protrusions 48 on disrupting the flow of the heat medium is stronger on the downstream side of the cooling flow passage 28 than on the upstream side, and regions having different effects of disrupting the flow of the heat medium are set at different positions in the flow passage length direction of the cooling flow passage 28.

[0117] Furthermore, in this embodiment, the three protrusion-forming portions 40, 40, 40 differ in the number and arrangement of the protrusions 48. Specifically, the more forward the protrusion-forming portion 40 is located in the flow path width direction of the cooling flow path 28, the greater the number of protrusions 48 formed, and the closer the spacing between the protrusions 48 is in the flow path length direction, the narrower the spacing. As a result, downstream of the parallel flow path portion 58, the more forward the flow path portion 56 is located, and the regions having different effects of disrupting the flow of the heat medium are set at different positions in the flow path width direction of the cooling flow path 28.

[0118] In this way, by adopting the inner fin 90 according to this embodiment, the effect of disturbing the flow of the heat medium to generate vortices and turbulence (turbulence promotion effect) is set to differ partially in the parallel flow path section 58, so that high cooling performance can be achieved in the areas where the turbulence promotion effect is strong, making it possible to efficiently cool the battery pack 62.

[0119] In particular, in this embodiment, the turbulence promotion effect is more pronounced downstream of the cooling flow path 28 (parallel flow path section 58), and the downstream heat medium that has been warmed in the area close to the cooling wall sections 30, 30 by heat exchange with the battery pack 62 is stirred, thereby ensuring effective cooling performance downstream as well. Also, in this embodiment, the turbulence promotion effect is more pronounced in the front, and therefore the front section of the battery pack 62, where the terminal sections 64 are provided and where heat generation is likely to be large, can be efficiently cooled.

[0120] The arrangement of the protrusions 48 shown in this embodiment is merely an example and can be changed as appropriate, taking into consideration, for example, the heat generation pattern (temperature distribution) of the battery pack 62, the required cooling performance, etc. Furthermore, the turbulence promotion effect of the protrusions 48 differs not only depending on the number and arrangement of the protrusions 48, but also on the size (including the height) of the protrusions 48, the shape, the surface friction resistance, etc., and therefore, regions with different turbulence promotion effects can be set by varying the size of the protrusions 48, etc.

[0121] Furthermore, for example, if it is necessary to set areas with different turbulence-promoting effects only for the battery pack 62 that is overlaid on one of the cooling surfaces 32, the setting of areas with different turbulence-promoting effects due to differences in the arrangement, number, shape, size, surface friction resistance, etc. of the protrusions 48 as shown in this embodiment may be applied to only one of the first protrusions 48a and the second protrusions 48b.

[0122] 10 to 13 show an inner fin 100 constituting a cooling heat exchanger according to a fifth embodiment of the present invention. The inner fin 100 of this embodiment can be used in place of the inner fin 72 of the second embodiment. The left side of Fig. 10 is the upstream side of the cooling flow path, and the right side of Fig. 10 is the downstream side of the cooling flow path.

[0123] The inner fin 100 is a thin plate made of metal, synthetic resin, or the like, and extends in the left-right direction with a cross-sectional shape that is folded back in a zigzag or wave shape, similar to the inner fin 72 of the second embodiment. The inner fin 100 of this embodiment is a pressed metal piece.

[0124] The inner fin 100 is formed with protrusions 102. The protrusions 102 extend in a generally V-shape on the surface of the inner fin 100 and taper (become narrower) toward the upstream side of the cooling flow path. The protrusions 102 are generally V-shaped when viewed from the up-down direction. The protrusions 102 are composed of a first protrusion 102a protruding from the upper surface side of the inner fin 100 and a second protrusion 102b protruding from the lower surface side of the inner fin 100.

[0125] Fig. 11 shows an enlarged cross section of one protrusion 102 in the flow channel length direction. In the cross section shown in Fig. 11, the protrusion 102 has a tapered cross section that narrows in the flow channel length direction toward the protrusion tip. More specifically, in the cross section shown in Fig. 11, the protrusion 102 has a cross-sectional outer shape that continuously includes an arc-shaped protrusion apex 104, an upstream inclined portion 108 that extends at an incline upstream from the upstream end of the protrusion apex 104 toward a protrusion base 106 (the end of the protrusion 102 connected to the swash plate portion 74), and a downstream inclined portion 110 that extends at an incline downstream from the downstream end of the protrusion apex 104 toward the protrusion base 106. The cross section of the protrusion 102 shown in FIG. 11 is a cross section in the flow path length direction passing through the center in the flow path width direction, but any cross section of the protrusion 102 perpendicular to the ridge line 54 has a cross-sectional shape similar to that shown in FIG. 11, and the same numerical ranges and the like as explained in FIG. 11 are suitably applied to any cross section perpendicular to the ridge line 54.

[0126] In the cross section in the flow channel length direction shown in FIG. 11 , the radius of curvature R of the protrusion apex 104, including the ridge line 54, is within a range of 0.05 to 1.5 times the length dimension L of the protrusion base 106 in the flow channel length direction, and more preferably within a range of 0.2 to 1.45 times. By making the radius of curvature R of the protrusion apex 104 0.05 times or more the length dimension L of the protrusion base 106, the protrusion apex 104 has a smooth arc-shaped cross section without any substantial corners. Furthermore, by making the radius of curvature R of the protrusion apex 104 1.5 times or less the length dimension L of the protrusion base 106, it is possible to prevent the length dimension of the protrusion 102 in the flow channel length direction from becoming excessively long, and it is possible to set the inclination angles α and β of the upstream inclined portion 108 and the downstream inclined portion 110, which smoothly connect to the protrusion apex 104, to be sufficiently large. In this embodiment, the radius of curvature R of the projection top 104 is set to be within the range of 0.05 to 0.5 times the length dimension L of the projection base 106 .

[0127] Although the upstream inclined portion 108 may have a curved shape, in this embodiment it has a linear shape. The upper end of the upstream inclined portion 108 extends tangentially from the upstream end of the protrusion apex 104 and smoothly connects to the protrusion apex 104 without any corners. The lower end of the upstream inclined portion 108 may be curved in an arc shape, in which case it is desirable that the lower end of the upstream inclined portion 108 smoothly connect to the swash plate portion 74 that forms the bottom surface of the cooling flow path 28 without any corners.

[0128] The inclination angle α of the upstream inclined portion 108 relative to the swash plate portion 74 that forms the bottom surface of the cooling flow channel 28 is set to be within a range of 20 to 70 degrees, and more preferably within a range of 30 to 60 degrees. Note that when the upstream inclined portion 108 has a curved shape, the inclination angle α of the upstream inclined portion 108 relative to the swash plate portion 74 can be understood as, for example, the average value of the inclination angles of the upstream inclined portion 108 relative to the swash plate portion 74.

[0129] By setting the inclination angle α of the upstream inclined portion 108 to 20° or more, the flow of the heat medium from the upstream side toward the protrusions 102 is effectively disturbed by the upstream inclined portion 108, which forms a sufficiently large angle with the flow direction of the heat medium, thereby improving cooling performance through a stirring effect. Furthermore, by setting the inclination angle α of the upstream inclined portion 108 to 70° or less, it is possible to prevent the flow of the heat medium from being excessively restricted by the protrusions 102.

[0130] Although the downstream inclined portion 110 may have a curved shape, in this embodiment it has a linear shape. The upper end of the downstream inclined portion 110 extends tangentially from the downstream end of the protrusion apex 104 and smoothly connects to the protrusion apex 104 without any corners. The lower end of the downstream inclined portion 110 may be curved in an arc shape, in which case it is desirable that the lower end of the downstream inclined portion 110 smoothly connect to the swash plate portion 74 that forms the bottom surface of the cooling flow path 28 without any corners.

[0131] The inclination angle β of the downstream inclined portion 110 relative to the swash plate portion 74 that forms the bottom surface of the cooling flow channel 28 is set to a range of 20 to 70 degrees, and more preferably a range of 30 to 60 degrees. When the downstream inclined portion 110 has a curved shape, the inclination angle β of the downstream inclined portion 110 relative to the swash plate portion 74 can be understood as, for example, the average value of the inclination angle of the downstream inclined portion 110 relative to the swash plate portion 74.

[0132] By setting the inclination angle β of the downstream inclined portion 110 to 20° or more, it is expected that the flow of the heat medium that passes over the protrusions 102 will easily separate from the downstream inclined portion 110, thereby making it easier for a turbulent flow such as a vortex to occur downstream of the protrusions 102. Furthermore, by setting the inclination angle β of the downstream inclined portion 110 to 70° or less, the flow of the heat medium along the downstream inclined portion 110 is also ensured, and it is expected that the heat medium will be efficiently stirred by merging with the flow that has separated from the downstream inclined portion 110.

[0133] As shown in Figures 12 and 13, the protrusion height of the protrusions 102 in this embodiment varies in the front-to-rear direction, which is the width direction of the flow channel. The multiple protrusions 102 are each composed of a central low protrusion 116, which has a low protrusion 112 with a low protrusion height at the front-to-rear center and high protrusions 114 with a high protrusion height at both front and rear ends, and a central high protrusion 118, which has a high protrusion 114 with a high protrusion height at the front-to-rear center and low protrusions 112 with a low protrusion height at both front and rear ends. Both the first protrusion 102a and the second protrusion 102b are composed of a plurality of central low protrusions 116 and a plurality of central high protrusions 118. For ease of viewing, Figures 11 and 12 show only the protrusion 102 located closest to the user in each cross-sectional view.

[0134] 10 , the plurality of first protrusions 102a and second protrusions 102b arranged in the flow path length direction each have a central low protrusion 116 and a central high protrusion 118 arranged alternately in the left-right direction, which is the flow path length direction. Therefore, in the center of the flow path section 56 in the flow path width direction, the low protrusions 112 of the central low protrusion 116 and the high protrusions 114 of the central high protrusion 118 are arranged alternately in the flow path length direction. In addition, at both end portions of the flow path section 56 in the flow path width direction, the high protrusions 114, 114 of the central low protrusion 116 and the low protrusions 112, 112 of the central high protrusion 118 are arranged alternately in the flow path length direction.

[0135] According to the inner fin 100 of this embodiment, the high protruding portion 114 with a large protruding height dimension can achieve a stronger stirring effect of the heat medium, and the low protruding portion 112 with a small protruding height dimension suppresses the flow resistance of the heat medium, thereby reducing pressure loss.

[0136] In this embodiment, the low-protrusion portions 112 and the high-protrusion portions 114 are arranged adjacent to each other in the flow path length direction, and the heat transfer medium that flows smoothly through the low-protrusion portions 112 is efficiently agitated by the high-protrusion portions 114 located downstream of the low-protrusion portions 112, thereby efficiently improving cooling performance. Furthermore, the heat transfer medium whose flow has been strongly disturbed by the high-protrusion portions 114 flows relatively smoothly through the low-protrusion portions 112 located downstream of the high-protrusion portions 114, and therefore is less likely to stagnate.

[0137] Furthermore, the heat medium flows more easily through the low protrusions 112, which have lower flow resistance than the high protrusions 114, but by arranging the central low protrusions 116 and the central high protrusions 118 alternately in the flow path length direction, the low protrusions 112 are alternately located in the center and both end portions in the flow path width direction in the flow path length direction. Therefore, in the flow path section 56, a flow of the heat medium meanders in the flow path width direction so as to connect the low protrusions 112, which is expected to have the effect of eliminating bias in the temperature distribution of the heat medium in the flow path width direction.

[0138] 14 to 16 show an inner fin 120 constituting a cooling heat exchanger according to a sixth embodiment of the present invention. The inner fin 120 has a zigzag cross-sectional shape similar to the inner fin 100 according to the fifth embodiment.

[0139] The inner fin 120 is provided with protrusions 122. The protrusions 122 are composed of multiple first protrusions 122a protruding from the upper surface and multiple second protrusions 122b protruding from the lower surface. Like the protrusions 102 of the inner fin 100, the protrusions 122 are V-shaped as a whole when viewed in the vertical direction, but are not continuous at the end on the upstream side (left side in FIG. 14 ). That is, the protrusions 122 of this embodiment are composed of two mutually spaced convex portions 124, 124 that extend obliquely from the center in the flow channel width direction to both sides and downstream (right side in FIG. 14 ).

[0140] Like the protrusion 102 of the fifth embodiment, the protrusion 122 of this embodiment includes a central low protrusion 116 and a central high protrusion 118. Furthermore, in this embodiment, the multiple central low protrusions 116 and the multiple central high protrusions 118 are arranged alternately in the flow channel length direction. Note that the protrusion 122 of this embodiment is composed of two protrusions 124, 124 that are spaced apart from each other in the center portion in the flow channel width direction, and therefore the low protrusion 112 of the central low protrusion 116 and the high protrusion 114 of the central high protrusion 118, which are located on the center side in the flow channel width direction, are provided on the two protrusions 124, 124, respectively.

[0141] The inner fin 120 having the structure according to this embodiment can also achieve the same effects as the inner fin 100 of the fifth embodiment. Furthermore, since the protrusions 122 are provided only on the swash plate portion 74 and not on the top portion 76, it is expected that the protrusions 122 can be easily formed by press working.

[0142] 17 shows a part of an inner fin 130 constituting a cooling heat exchanger according to a seventh embodiment of the present invention. The inner fin 130 has a plurality of protrusions 102 arranged in the longitudinal direction of the flow path, the protrusion heights and intervals of which vary.

[0143] More specifically, the protrusion height of the multiple protrusions 102 increases toward the downstream side (the right side in FIG. 17 ), and the spacing between adjacent protrusions 102 in the flow path length direction decreases toward the downstream side. Note that the rate of change in the protrusion height of the protrusions 102 and the rate of change in the spacing between the protrusions 102 may vary, but in this embodiment, these rates of change are constant. The protrusion height of the protrusions 102 varies in the flow path width direction, but the protrusion height increases toward the downstream side when comparing the low protrusions 112 and / or the high protrusions 114.

[0144] In this way, by setting the protrusion height of the protrusions 102 to increase toward the downstream side, the stirring action of the protrusions 102 can be more efficiently exerted on the downstream side where the temperature difference between the upper heat medium and the lower heat medium is likely to become large due to heat exchange, and cooling performance can be maintained further downstream. Also, by setting the spacing between the protrusions 102, 102 to become narrower toward the downstream side, the stirring action of the protrusions 102 can be more efficiently obtained on the downstream side, and cooling performance can be maintained further downstream.

[0145] Although the embodiments of the present invention have been described in detail above, the present invention is not limited to the specific descriptions. For example, the specific shape of the inner fin is not limited to the shapes shown in the first to fourth embodiments, and is not particularly limited as long as it can divide the cooling flow path 28 in two in the opposing direction of the pair of cooling wall portions 30, 30 to achieve a double-sided cooling structure. Furthermore, while the inner fin preferably also divides the cooling flow path 28 in the flow path width direction, division in the flow path width direction is not essential, and the inner fin may only define two flow path regions, one on the side of the first member 14 facing the cooling wall portion 30 and the other on the side of the second member 16 facing the cooling wall portion 30.

[0146] The outer wall member is not necessarily limited to a structure in which the first member 14 and the second member 16 are stacked together. For example, a structure in which a pair of lids, each with a supply hole and a discharge hole, are attached to both ends of a cylindrical outer wall body integrally provided with a pair of cooling walls, can be adopted. In this structure, for example, the inner fins can be housed and arranged in the internal region of the outer wall member by inserting them into the inner periphery of the outer wall body in the axial direction of the outer wall body before attaching the lids to the outer wall body. Note that the cylindrical outer wall body can be easily manufactured by, for example, extrusion molding or pultrusion molding of a metal material.

[0147] The inner fin may not have an elastically deformable portion and may be entirely rigid. In this case, the inner fin can be expected to function as a reinforcing member, thereby increasing the deformation rigidity of the cooling heat exchanger and improving its load-bearing capacity.

[0148] The protrusions are not necessarily limited to a V-shape, and may be, for example, hemispherical, columnar, or stepped. The protrusions may also be formed as ridges extending in a direction substantially perpendicular to the heat medium flow direction. The V-shaped protrusions are not necessarily limited to a strict V-shape; as long as they are V-shaped overall on the surface of the inner fin, they may be curved, partially separated, or have different angles of inclination relative to the flow path direction on both sides of the width direction. The protrusions may also be V-shaped in the opposite direction to the above-described embodiments, narrowing toward the downstream side.

[0149] While FIG. 11 shows the protrusion 102 in which the inclination angle of the upstream inclined portion 108 is within the range of 20 to 70 degrees, a protrusion 140 as shown in FIG. 18 may also be employed. That is, the protrusion 140 shown in FIG. 18 has a large radius of curvature at the protrusion apex 142, and both the upstream inclined portion 144, which is the upstream side, and the downstream inclined portion 146, which is the downstream side, are curved surfaces. The protrusion apex 142 and the swash plate portion 74 are smoothly connected without corners in a cross section taken along the flow path length direction. Therefore, the entire cross-sectional outline of the protrusion 140 in the flow path length direction has a continuous curved shape. In the protrusion 140 shown in FIG. 18, the radius of curvature R of the protrusion apex 142, which is arc-shaped in a cross section taken along the flow path length direction, is preferably 0.7 times or more, and more preferably 1 time or more, the length L of the protrusion base 148. 18 , the inclination angle α of the upstream inclined portion 144 of this embodiment relative to the bottom surface of the flow path section 56 is 25° or less, and the inclination angle β of the downstream inclined portion 146 of this embodiment is 25° or less. In short, compared to the protrusion 102 shown in FIG. 11 , the protrusion 140 of this embodiment has a flatter shape in the cross section of the flow path length direction, with a smaller ratio of the protrusion height dimension to the length dimension L of the protrusion base 148, and the rate of change in the flow path cross-sectional area due to the protrusion 140 is smaller. Such protrusions 140 reduce pressure loss caused by the heat medium flowing over the protrusions 140, making it possible to circulate the heat medium using an inexpensive pump with relatively low performance.

[0150] The protrusions do not necessarily need to be provided continuously across the entire width of the flow path section. However, the width of the protrusions in the width direction is preferably 50% or more, more preferably 70% or more, of the width of the flow path section. This restricts the flow that bypasses the protrusions and makes it easier for the flow to overcome the protrusions, thereby efficiently disrupting the flow of the heat medium. Note that, when a zigzag inner fin is used, for example, and the flow path width of the flow path section varies in the depth direction, the width of the protrusions is preferably 50% or more, more preferably 70% or more, of the maximum width of the flow path section (the width between the apexes of the zigzag inner fins). Note that, when the flow path width of the flow path section varies in the length direction, the width of the protrusions is preferably set within the above-mentioned range with respect to the flow path width at the position where the protrusions are provided.

[0151] The first and second members 14, 16 may be made of synthetic resin. In this case, in order to ensure a high heat transfer rate, the first and second members 14, 16 are formed of a thermally conductive synthetic resin obtained by mixing a thermally conductive filler such as aluminum oxide (alumina), silica, or silicon carbide with a synthetic resin material such as polyphenylene sulfide (PPS), polyamide, polypropylene, or polybutylene terephthalate (PBT).

[0152] In the state in which the battery packs 62 are attached to the cooling heat exchanger 10 shown in Fig. 6, it is also possible to overlap the lower cooling surface 32 of another cooling heat exchanger 10 with the upper surface of the battery pack 62 that is overlapped with the upper cooling surface 32, thereby allowing the battery pack 62 to be cooled from both above and below. Similarly, it is also possible to overlap the upper cooling surface 32 of another cooling heat exchanger 10 with the lower surface of the battery pack 62 that is overlapped with the lower cooling surface 32 in Fig. 6. In short, by arranging the cooling heat exchangers 10 and battery packs 62 in a stacked configuration by overlapping them alternately in the vertical direction, it is possible to cool each of the multiple battery packs 62 from both above and below.

[0153] When multiple cooling heat exchangers 10 are arranged in a stacked configuration, for example, supply holes and discharge holes may be formed at both left and right ends of the second member 16, and the supply holes 20 and discharge holes 22 of the first member 14 of one cooling heat exchanger 10 arranged adjacent to each other in the vertical direction may be interconnected and communicated with the supply holes and discharge holes of the second member 16 of the other cooling heat exchanger 10. In this way, the cooling flow paths 28 of the multiple cooling heat exchangers 10 arranged in a stacked configuration can be connected to a single external flow path, and the heat medium can be supplied to and discharged from those cooling flow paths 28 collectively.

[0154] The object to be cooled is not necessarily limited to a battery for an electric vehicle, and may be, for example, a stationary battery for industrial use, etc. Furthermore, while the first embodiment illustrates a case in which multiple battery packs 62 are arranged on the cooling surface 32 of one cooling heat exchanger 10, for example, one battery pack 62 may be arranged on the cooling surface 32 of one cooling heat exchanger 10. Furthermore, for example, one battery pack 62 may be arranged across multiple cooling heat exchangers 10.

[0155] REFERENCE SIGNS LIST 10 Cooling heat exchanger (first embodiment) 12 Outer wall member 14 First member 16 Second member 18 Recess 20 Supply hole 22 Discharge hole 24 Supply port 26 Discharge port 28 Cooling flow path 30 Cooling wall portion 32 Cooling surface 34 Inner fin 35 End wall portion 36 End wall connecting portion 37 End wall main body portion 38 Intermediate partition portion 40 Protrusion forming portion 42 Partition wall portion 44 Partition wall main body portion 46 Partition wall connecting portion 48 Protrusion 48a First protrusion 48b Second protrusion 50 Upstream inclined surface 52 Downstream inclined surface 54 Ridge line 56 Flow path portion 58 Parallel flow path portion 60a First narrowed flow path 60b Second narrowed flow path 62 Battery pack (cooling target) 64 Terminal portion 70 Cooling heat exchanger (second embodiment) 72 Inner fin 74 Swash plate portion 76 Top portion 78 Protrusion 78a First protrusion 78b Second protrusion 80 Cooling heat exchanger (third embodiment) 82 Inner fin 84 Protrusion 84a First protrusion 84b Second protrusion 90 Inner fin (fourth embodiment) 100 Inner fin (fifth embodiment) 102 Protrusion 102a First protrusion 102b Second protrusion 104 Protrusion top portion 106 Protrusion base portion 108 Upstream inclined portion 110 Downstream inclined portion 112 Low protrusion portion 114 High protrusion portion 116 Central low protrusion 118 Central high protrusion 120 Inner fin (sixth embodiment) 122 Protrusion 122a First protrusion 122b Second protrusion 124 Convex portion 130 Inner fin (seventh embodiment) 140 Protrusion (another embodiment) 142 Protrusion apex 144 Upstream inclined portion 146 Downstream inclined portion 148 Protrusion base R Curvature radius of protrusion apex L Length dimension of protrusion base α Inclination angle of upstream inclined portion β Inclination angle of downstream inclined portion

Claims

1. A cooling heat exchanger having a cooling flow path formed inside through which a cooling heat medium flows, for cooling an object to be cooled that is placed over a cooling surface provided on the surface, wherein a hollow outer wall member having the cooling flow path inside is provided, and a pair of cooling wall sections having the cooling surface on their surfaces are provided at mutually opposing portions of the outer wall member, and a plate-shaped inner fin is arranged in the inner region of the outer wall member, dividing the inner region into two in the opposing direction of the pair of cooling wall sections, and the inner fins have first and second protrusions integrally formed on each side.

2. A cooling heat exchanger as claimed in claim 1, wherein the cooling flow path comprises a parallel flow path section made up of a plurality of flow path sections that are separated in the flow path width direction by the inner fins and extend adjacent to each other in parallel, and the flow direction of the heat transfer medium in the plurality of flow path sections that make up the parallel flow path section is the same.

3. A cooling heat exchanger as claimed in claim 1 or 2, wherein the outer wall member is constructed by stacking a first member constituting one of the cooling wall sections and a second member constituting the other of the cooling wall sections in the opposing direction of the pair of cooling wall sections, and the inner fin is disposed between the opposing first member and second member.

4. A cooling heat exchanger as claimed in any one of claims 1 to 3, wherein the inner fin has a cross section that is folded back in a zigzag or wave pattern in the opposing direction of the pair of cooling wall sections, and the first protrusion and the second protrusion are formed between the apexes of adjacent folds on the inner fin.

5. A cooling heat exchanger as claimed in any one of claims 1 to 3, wherein the inner fin is arranged apart from both of the pair of cooling wall sections in the outer wall member and has an intermediate partition section that divides the space between opposing surfaces of the pair of cooling wall sections in the opposing direction of the pair of cooling wall sections, the first protrusion and the second protrusion are formed on the intermediate partition section, the inner fin has partition sections that protrude on both sides from the intermediate partition section towards the pair of cooling wall sections, and the partition sections divide the internal area of ​​the outer wall member into a plurality of flow path sections in the flow path width direction of the cooling flow path.

6. A cooling heat exchanger as claimed in any one of claims 1 to 5, wherein the first protrusion and the second protrusion are V-shaped on the surface of the inner fin and narrow toward the upstream side of the cooling flow path.

7. A cooling heat exchanger according to any one of claims 1 to 6, wherein the inner fins are arranged partially in the length direction of the cooling flow path.

8. A cooling heat exchanger as claimed in any one of claims 1 to 7, wherein the cooling flow path has regions in which the effect of disrupting the flow of the heat medium differs from one another due to at least one of the plurality of first protrusions and the plurality of second protrusions.

9. A cooling heat exchanger according to claim 8, wherein the regions having different effects of disturbing the flow of the heat medium are set at different positions in the flow direction of the heat medium in the cooling flow passage.

10. A cooling heat exchanger as described in claim 9, wherein the regions set at different positions in the flow direction of the heat medium in the cooling flow path have different effects of disturbing the flow of the heat medium, and the more downstream the region is set, the stronger the effect of disturbing the flow of the heat medium.

11. A cooling heat exchanger as claimed in any one of claims 8 to 10, wherein the cooling flow path comprises a parallel flow path section made up of a plurality of flow path sections separated by the inner fins and extending adjacent to each other in parallel, the heat medium flows in the same direction in the plurality of flow path sections making up the parallel flow path section, and at least one pair of adjacent flow path sections in the parallel flow path section are set with the regions having mutually different effects of disturbing the flow of the heat medium.

12. A cooling heat exchanger as claimed in any one of claims 8 to 11, wherein the regions having different effects of disrupting the flow of the heat medium are set by at least one of a difference in the distance between the plurality of first projections in the flow direction of the heat medium and a difference in the distance between the plurality of second projections.

13. A cooling heat exchanger as set forth in any one of claims 8 to 12, wherein the regions having different effects of disrupting the flow of the heat medium are set by at least one of differences in height between the plurality of first projections and differences in height between the plurality of second projections.

14. A cooling heat exchanger according to any one of claims 1 to 13, wherein the object to be cooled is a battery.

15. A cooling heat exchanger according to any one of claims 1 to 14, wherein the inner fins are provided with elastically deforming portions that allow the pair of cooling wall portions to approach each other by elastic deformation.

16. A cooling heat exchanger as claimed in any one of claims 1 to 15, wherein the first protrusion and the second protrusion each extend across the entire width of the cooling flow path and are continuous with the side wall portions of the cooling flow path at both ends.

17. A cooling heat exchanger as set forth in any one of claims 1 to 16, wherein the protrusion height of at least one of the first protrusions and the second protrusions varies in the width direction of the cooling flow path, with either a low protrusion with a low protrusion height or a high protrusion with a high protrusion height being located in the central portion in the width direction of the flow path, and the other of the low protrusions and the high protrusions being located at both end portions of the first protrusions and the second protrusions in the width direction of the flow path.

18. A cooling heat exchanger as described in claim 17, wherein at least one of the plurality of first protrusions and the plurality of second protrusions arranged in a line in the flow path length direction of the cooling flow path is configured by alternatingly arranging in the flow path length direction of the cooling flow path a central low protrusion in which the low protrusion is set in the central part of the flow path width direction of the cooling flow path and a high protrusion is set at both end parts, and a central high protrusion in which the high protrusion is set in the central part of the flow path width direction of the cooling flow path and a low protrusion is set at both end parts.

19. A cooling heat exchanger as claimed in any one of claims 1 to 18, wherein at least one of the first protrusions and the second protrusions has a cross-sectional shape that tapers towards the protrusion tip in a cross section of the cooling flow path in the flow path length direction, and wherein an arc-shaped protrusion apex, an upstream inclined portion that extends at an angle from the protrusion apex towards the upstream side of the cooling flow path towards the protrusion base which is the bottom side of the cooling flow path, and a downstream inclined portion that extends at an angle from the protrusion apex towards the downstream side towards the protrusion base are provided smoothly and continuously without corners.

20. A cooling heat exchanger as set forth in claim 19, wherein, in a cross section of the cooling flow path in the flow path length direction, the radius of curvature of the projection top is within a range of 0.05 to 1.5 times the length dimension of the projection base, and, in a cross section of the cooling flow path in the flow path length direction, the inclination angle of the upstream inclined portion relative to the bottom surface of the cooling flow path is within a range of 20 to 70 degrees.

21. A cooling heat exchanger according to claim 19, wherein the inclination angle of the upstream inclined portion relative to the bottom surface of the cooling flow path is 25° or less in a cross section of the cooling flow path in the flow path length direction.

22. A cooling heat exchanger as set forth in any one of claims 1 to 21, wherein at least one of the first protrusions and the second protrusions aligned in the cooling flow path in the flow path length direction has a protruding height that increases downstream.

23. A cooling heat exchanger as set forth in any one of claims 1 to 22, wherein at least one of the first protrusions and the second protrusions arranged in the cooling flow path in the flow path length direction has a spacing in the flow path length direction that narrows toward downstream.

24. A cooling heat exchanger as set forth in any one of claims 1 to 23, wherein at least one of the first protrusions and the second protrusions aligned in the cooling flow path in the flow path length direction has a protruding height that increases toward downstream, and the spacing between the protrusions in the flow path length direction of the cooling flow path narrows toward downstream.

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