Heat exchanger for a vehicle

Abstract

Heat exchanger (1) for a vehicle, wherein: the vehicle includes a drivetrain designed such that an engine coolant, an engine oil and a transmission oil flow through the drivetrain, and that the flow rate of the engine oil and the flow rate of the transmission oil are different from each other, the heat exchanger (1) comprises the following: a first flow passage (11) through which the engine coolant flows, a second flow passage (12) through which the engine oil flows, and a third flow passage (13) through which the transmission oil flows, the first flow passage (11), the second flow passage (12) and the third flow passage (13) are subdivided by laminating several plates (10), the heat exchanger (1) is designed such that heat exchange is carried out between the respective flow passages which are arranged next to each other in a lamination direction of the several of the plates (10), the heat exchanger (1) includes a region in which the first flow passage (11) is located only next to the third flow passage (13), the drivetrain is designed in such a way that the flow rate of the transmission oil is lower than the flow rate of the engine oil, the heat exchanger (1) comprises a first region and a second region, such that the first region comprises at least one flow passage group in which the first flow passage (11), the third flow passage (13) and the first flow passage (11) are located next to each other in succession, and a region in which the first flow passage (11) is located only next to the third flow passage (13), and that the second region comprises at least one flow passage group in which the second flow passage (12), the third flow passage (13), the second flow passage (12), the first flow passage (11) and the second flow passage (12) are located next to each other in succession, and the first region and the second region lie next to each other in the lamination direction.

Description

BACKGROUND OF THE INVENTION 1. Field of the Invention

[0001] The invention relates to a heat exchanger for a vehicle. 2. Description of the state of the art

[0002] A three-phase heat exchanger for a vehicle, mounted in a vehicle to exchange heat between an engine coolant (coolant), an engine oil, and a transmission oil, is known. For example, JP 2013-113578 A discloses a heat exchanger for a vehicle that exchanges heat between the engine coolant and both the engine oil and the transmission oil by disposing a flow passage for the engine coolant between a flow passage for the engine oil and a flow passage for the transmission oil.

[0003] Furthermore, WO 2008 / 061362 A1 discloses a heat exchanger device in which a multi-fluid or at least three-fluid heat exchanger is mounted externally but in combination with a two-fluid heat exchanger. The multi-fluid heat exchanger comprises three fluid passages or conduits, wherein heat energy can be efficiently transferred between at least one of the fluid conduits and each of the other fluid conduits. The multi-fluid heat exchanger and the two-fluid heat exchanger are arranged such that the two heat exchangers share a common fluid, so that the multi-fluid heat exchanger enables heat transfer to or from the common fluid to the two other fluids in the multi-fluid heat exchanger, thereby improving the overall heat transfer between the fluids.

[0004] JP 2013-113 578 A discloses a vehicle heat exchanger comprising: a heat dissipating part formed by laminating a plurality of plates so that first, second and third working fluids are separated into first, second and third working fluids, respectively.third passage and the first, second, and third working fluids circulate without mixing with each other; a branch part which connects an inflow port through which one of the first, second, and third working fluids can flow in with an outflow port for discharging a working fluid, and which allows one of the working fluids to bypass the heat-dissipating part depending on the temperature of the one of the working fluids; and a valve unit which is mounted in a position corresponding to the inflow port and which allows one of the working fluids to selectively flow into the heat-dissipating part or the branch part depending on the temperature of the one of the working fluids flowing into the inflow port.

[0005] In addition, DE 10 2012 105 644 A1 discloses a heat exchanger comprising: a heat radiating section which is provided with first, second and third connecting lines which are formed in a predetermined order by stacking a plurality of plates, and which accommodates first, second and third operating fluids in the first, second and third connecting lines, respectively, wherein the first, second and third operating fluids are cooled during passage through the first, second and third connecting lines, respectively.the third connection line exchanges heat with each other, and wherein the first, second, and third operating fluids are not mixed with each other during circulation, and a branch portion connecting an inflow hole for inflow of one of the first, second, and third operating fluids with an outflow hole for discharging the one operating fluid, which is adapted such that the one operating fluid bypasses the heat radiating portion according to a temperature of the one operating fluid, and which is mounted on an outer side of the heat radiating portion. SUMMARY OF THE INVENTION

[0006] In general vehicle powertrains, the flow rate of the transmission oil is often lower than the flow rates of the engine coolant and the engine oil. In this case, in the heat exchanger for the vehicle in which the flow passages are arranged such that the engine coolant exchanges heat with both the engine oil and the transmission oil, as described in JP 2013-113578 A, the amount of heat exchange between the transmission oil and the engine coolant is smaller than the amount of heat exchange between the engine oil and the engine coolant. Accordingly, if the flow rate of the transmission oil is lower than the flow rates of the other fluids, the conventional configuration may be unable to sufficiently raise or lower the temperature of the transmission oil.

[0007] Furthermore, in certain vehicle powertrains, the flow rate of the engine oil may be lower than the flow rates of the engine coolant and transmission fluid. In this case, in the vehicle heat exchanger, as described in JP 2013-113578 A, the amount of heat exchange between the engine oil and the engine coolant is smaller than the amount of heat exchange between the transmission fluid and the engine coolant. Accordingly, if the flow rate of the engine oil is lower than the flow rates of the other fluids, the conventional configuration may not be able to sufficiently raise or lower the temperature of the engine oil.

[0008] The above problems and the resulting object are / are solved by the subject matter of claims 1 and 2. Advantageous developments of the invention are the subject matter of the subsequent dependent claims.

[0009] The invention provides a heat exchanger for a vehicle capable of increasing the amount of heat exchange between a fluid whose flow rate is relatively low and an engine coolant when heat is exchanged between a plurality of fluids.

[0010] One aspect of the invention is a heat exchanger for a vehicle. The vehicle includes a powertrain configured such that an engine coolant, an engine oil, and a transmission oil flow through the powertrain, and such that a flow rate of the engine oil and a flow rate of the transmission oil are different from each other. The heat exchanger includes a first flow passage, a second flow passage, and a third flow passage. The engine coolant flows through the first flow passage. The engine oil flows through the second flow passage. The transmission oil flows through the third flow passage. The first flow passage, the second flow passage, and the third flow passage are divided by laminating a plurality of plates. The heat exchanger is configured such that heat exchange is performed between the respective flow passages arranged side by side in a lamination direction of the plurality of plates.The heat exchanger includes a region in which the first flow passage is located only adjacent to that of the second flow passage and the third flow passage through which a fluid flows at a lower flow rate.

[0011] Thus, the heat exchanger for the vehicle has a region in which the first flow passage is located adjacent to the second flow passage and the third flow passage, through which the fluid flows with a lower flow rate in the lamination direction. Therefore, in this region, heat can be exchanged between the fluid with a lower flow rate and the engine coolant without being affected by the other fluid.

[0012] In the heat exchanger for the vehicle, the powertrain is configured such that a flow rate of the transmission oil is lower than a flow rate of the engine oil. The heat exchanger includes a first region and a second region such that the first region includes at least one flow passage group in which the first flow passage, the third flow passage, and the first flow passage are sequentially located adjacent to each other, and includes a region in which the first flow passage is only adjacent to the third flow passage, and the second region includes at least one flow passage group in which the second flow passage, the third flow passage, the second flow passage, the first flow passage, and the second flow passage are sequentially located adjacent to each other. The first region and the second region are adjacent to each other in the lamination direction.

[0013] Thus, the heat exchanger for the vehicle has a region where the first flow passage is adjacent to the third flow passage in the lamination direction. Therefore, in this region, heat can be exchanged between the transmission oil and the engine coolant without being affected by the engine oil. Accordingly, even if the heat exchanger is installed in a vehicle with a powertrain where the flow rate of the transmission oil is lower than the flow rate of the engine oil, the temperature of the transmission oil can be sufficiently raised or lowered.

[0014] According to another aspect of the invention, in the heat exchanger for the vehicle, the powertrain is configured such that a flow rate of the engine oil is lower than a flow rate of the transmission oil. The heat exchanger includes a first region and a second region such that the first region includes at least one flow passage group in which the first flow passage, the second flow passage, and the first flow passage are sequentially adjacent to each other, and includes a region in which the first flow passage is only adjacent to the second flow passage, and the second region includes at least one flow passage group in which the third flow passage, the second flow passage, the third flow passage, the first flow passage, and the third flow passage are sequentially adjacent to each other. The first region and the second region are adjacent to each other in the lamination direction.

[0015] Thus, the heat exchanger for the vehicle has a region where the first flow passage is adjacent to the second flow passage in the lamination direction. Therefore, in this region, heat can be exchanged between the engine oil and the engine coolant without being affected by the transmission oil. Accordingly, even if the heat exchanger is installed in a vehicle with a powertrain where the engine oil flow rate is lower than the transmission oil flow rate, the engine oil temperature can be sufficiently raised or lowered.

[0016] In the heat exchanger for the vehicle according to another illustrative aspect of the disclosure, the powertrain may be configured such that a flow rate of the transmission oil is lower than a flow rate of the engine oil.The heat exchanger may comprise a first region, a second region, and a third region, such that the first region comprises at least one flow passage group in which the first flow passage, the third flow passage, and the first flow passage are located adjacent to one another in sequence, and a region in which the first flow passage is only adjacent to the third flow passage, the second region comprises at least one flow passage group in which the third flow passage, the second flow passage, and the third flow passage are located adjacent to one another in sequence, and the third region comprises at least one flow passage group in which the second flow passage, the first flow passage, and the second flow passage are located adjacent to one another in sequence.The first region, the second region, and the third region may be adjacent to each other in the lamination direction in the order of the first region, the third region, and the second region.

[0017] Thus, the heat exchanger for the vehicle has a region where the first flow passage is adjacent to the third flow passage in the lamination direction. Therefore, in this region, heat can be exchanged between the transmission oil and the engine coolant without being affected by the engine oil. Accordingly, even if the heat exchanger is installed in a vehicle with a powertrain where the flow rate of the transmission oil is lower than the flow rate of the engine oil, the temperature of the transmission oil can be sufficiently raised or lowered.

[0018] In the heat exchanger for the vehicle, the third flow passage included in the second region may be located upstream of the third flow passage included in the first region in a flow direction of the transmission oil flowing through the heat exchanger.

[0019] Thus, the heat exchanger for the vehicle can efficiently raise or lower the temperature of the transmission oil whose flow rate is low by first exchanging heat between the transmission oil and the engine oil whose temperatures differ from each other by a small value in the second region, and then exchanging heat between the transmission oil that has exchanged heat with the engine oil and the engine coolant in the first region.

[0020] In the heat exchanger for the vehicle, the plates forming the first flow passage, the second flow passage, and the third flow passage may be provided with inflow holes and outflow holes for the engine coolant, the engine oil, and the transmission oil such that flow directions of fluids flowing through adjacent ones of the flow passages are opposite to each other.

[0021] Thus, by designing the vehicle heat exchanger so that adjacent fluids move in countercurrent, the relative amount of heat that can be exchanged between adjacent fluids per unit time and the number of opportunities for heat exchange between adjacent fluids per unit time can be increased compared to the case of parallel flow. In this way, the temperature difference between adjacent fluids can be rapidly reduced, and heat exchange can be carried out more efficiently than in the case of parallel flow.

[0022] In the heat exchanger for the vehicle, the inflow holes and the outflow holes may be arranged respectively through the plates at such positions that a straight line connecting the inflow and outflow holes of the second flow passage and a straight line connecting the inflow and outflow holes of the third flow passage cross each other.

[0023] Thus, the vehicle heat exchanger can increase the relative heat exchange amount between the engine oil and the transmission oil and the number of opportunities for heat exchange between them, compared to, for example, a case where the flow directions of the two fluids do not cross each other, by ensuring that the flow direction of the engine oil and the flow direction of the transmission oil do cross each other. Therefore, heat can be exchanged efficiently between the engine oil and the transmission oil. BRIEF DESCRIPTION OF THE DRAWINGS

[0024] Features, advantages, and technical and industrial significance of exemplary embodiments of the invention are described below with reference to the accompanying drawings, in which like numerals designate like elements, and in which: Fig. 1 is a view schematically showing the configuration of a heat exchanger for the vehicle according to the first embodiment of the invention, Fig. 2 is a view schematically showing flow directions of respective fluids and a sequence of heat exchange of the heat exchanger for the vehicle according to the first embodiment of the invention, Fig. 3 is a view schematically showing positions of inflow holes and outflow holes for the respective fluids in each plate forming a first region among respective flow passages of the heat exchanger for the vehicle according to the first embodiment of the invention, Fig. 4 is a view schematically showing positions of inflow holes and outflow holes for the respective fluids in each plate forming a second region under the respective flow passages of the heat exchanger for the vehicle according to the first embodiment of the invention, Fig. 5 is a graph showing how temperatures of the respective fluids change at the time of a cold state before completion of the warm-up phase (during the warm-up phase) of an engine and a transmission in a vehicle in which the heat exchanger for the vehicle is mounted, Fig. 6 is a graph showing temperatures of the respective fluids at the time of a warm state after the warm-up phase of the engine and the transmission in the vehicle in which the heat exchanger for the vehicle is mounted, Fig. Fig. 7 is a view schematically showing the configuration of a heat exchanger for the vehicle according to the second embodiment of the invention, Fig. 8 is a view schematically showing flow directions of respective fluids and a sequence of heat exchange of the heat exchanger for the vehicle according to the second embodiment of the invention, Fig. 9 is a view schematically showing positions of inflow holes and outflow holes for the respective fluids in each plate forming a first region among respective flow passages of the heat exchanger for the vehicle according to the second embodiment of the invention, Fig. 10 is a view schematically showing positions of inflow holes and outflow holes for the respective fluids in each plate forming a second region among the respective flow passages of the heat exchanger for the vehicle according to the second embodiment of the invention, Fig. 11 is a view schematically showing the configuration of a heat exchanger for the vehicle according to the third embodiment of the invention, Fig. 12 is a view schematically showing flow directions of respective fluids and a sequence of heat exchange of the heat exchanger for the vehicle according to the third embodiment of the invention, Fig. 13 is a view schematically showing positions of inflow holes and outflow holes for the respective fluids in each plate forming a first region under respective flow passages of the heat exchanger for the vehicle according to the third embodiment of the invention, Fig. 14 is a view schematically showing positions of inflow holes and outflow holes for the respective fluids in each plate forming a third region among the respective flow passages of the heat exchanger for the vehicle according to the third embodiment of the invention, and Fig. 15 is a view schematically showing positions of inflow holes and outflow holes for the respective fluids in each plate forming a second region among the respective flow passages of the heat exchanger for the vehicle according to the third embodiment of the invention. DETAILED DESCRIPTION OF EMBODIMENTS

[0025] A heat exchanger for a vehicle according to embodiments of the invention will be described with reference to the drawings. Furthermore, the invention is not limited to the following embodiments. Furthermore, components in the following embodiments of the invention include those that can be easily replaced by those skilled in the art or are substantially identical thereto.

[0026] Each of the heat exchangers for the vehicle according to the invention is a three-phase heat exchanger mounted in a vehicle to exchange heat between three fluids: an engine coolant (hereinafter referred to as the "engine coolant"), an engine oil (hereinafter referred to as the "engine oil"), and a transmission oil (hereinafter referred to as the "transmission oil"). For example, an AT vehicle, a CVT vehicle, and an HV vehicle can be enumerated as the vehicle in which each of the heat exchangers for the vehicle according to the invention is mounted (which also applies to the "vehicle" in the following description).

[0027] The heat exchanger for the vehicle according to the first embodiment of the invention is designed to be mounted in a vehicle having a powertrain through which engine coolant and engine oil flow, and in which the flow rate of the engine oil and the flow rate of the coolant oil are different from each other, particularly a powertrain in which the flow rate of the coolant oil is lower than the flow rates of the engine coolant and the engine oil. The heat exchanger according to the first embodiment of the invention mainly aims to increase the amount of heat exchange between the coolant oil, whose flow rate is low, and the engine coolant.

[0028] As in Fig. As shown in Figure 1, the heat exchanger 1 is formed by laminating a plurality of plates (plate bodies) 10 made of aluminum alloy or the like on a base 20 and integrally bonding them. Furthermore, in the heat exchanger 1, a flat plate 10a serving as a top cover member and a plurality of cup-shaped plates 10b are combined (superimposed) with each other, so that flow passages through which respective fluids flow are formed between two adjacent ones of the plates 10. Furthermore, the heat exchanger 1 is directly mounted on an engine unit of the vehicle, for example, via the base 20.

[0029] Although in Fig. 1, fins (for example, corrugated fins) are each housed between the plates 10. The plates 10 and the fins are each integrally bonded to each other by heat treatment or the like. Furthermore, the word "cup-shaped" used above refers to a shape having a hollowed flat surface, a bottom surface, and a side surface, such as the cup-shaped plates 10b shown in the drawing.

[0030] In the heat exchanger 1, as in particular in Fig. As shown in FIG. 1, first flow passages 11 for inducing engine coolant flow, second flow passages 12 for inducing engine oil flow, and third flow passages 13 for inducing coolant oil flow are formed through the heat exchanger 1 by laminating the plurality of plates 10 (the flat plate 10a and the cup-shaped plates 10b) together. Thus, the heat exchanger 1 is configured such that the respective fluids between those of the flow passages that are vertically adjacent to each other in a laminating direction of the plates 10 (hereinafter referred to simply as the "laminating direction") exchange heat with each other via the plates 10 (specifically, the undersides of the cup-shaped plates 10b).

[0031] It should be noted here that in Fig. 1, spaces corresponding to the first flow passages 11 are not hatched, spaces corresponding to the second flow passages 12 are hatched diagonally, and spaces corresponding to the third flow passages 13 are hatched in a dotted manner. Furthermore, the "flow passages" in the present embodiment of the invention specifically mean predetermined spaces divided by combining the plurality of plates 10 together.

[0032] The first flow passages 11, the second flow passages 12, and the third flow passages 13 are each arranged across the plates 10 (more precisely, the undersides of the cup-shaped plates 10b) and are divided such that the fluids flowing through the respective flow passages do not mix with each other. Furthermore, the flow passages through which the same fluid flows are in fluid communication with each other via interlayer flow communication passages 113, 123, and 133 (see Fig. 2), which will be described later.

[0033] As in Fig. 1, the heat exchanger 1 consists of a total of thirteen layers. The first flow passages 11 are arranged in the first, third, fifth, ninth, and thirteenth layers from the top, the second flow passages 12 are arranged in the sixth, eighth, tenth, and twelfth layers from the top, and the third flow passages 13 are arranged in the second, fourth, seventh, and eleventh layers from the top. In addition, numbers (1) to (13) shown in parentheses next to the respective flow passages in the drawing indicate layer numbers when the respective flow passages are counted from the top. The term "O-th layer" in the following description indicates the layer number when the respective flow passages are counted from the top, as is the case with the above-mentioned Fig. 1 is the case.

[0034] The heat exchanger 1 has two regions, namely a first region and a second region as regions where multiple fluids exchange heat with each other. The first region is a region aimed at increasing the amount of heat exchange between the engine oil and the engine coolant. The first region includes at least a three-layer flow passage group in which the first flow passage 11, the third flow passage 13, and the first flow passage 11 are arranged adjacent to each other in sequence, and the first flow passages 11 and the third flow passages 13 are arranged alternately in the lamination direction. As shown in Fig. 1, the first region according to the present embodiment of the invention consists of a total of five layers, namely the first flow passage 11, the third flow passage 13, the first flow passage 11, the third flow passage 13 and the first flow passage 11, which are arranged in this order from the top.

[0035] In addition, as in Fig. 1, the first region includes a region in which the first flow passage 11 is located only adjacent to the third flow passages 13 because it is the one of the second flow passage 12 and the third flow passage 13 through which the fluid flows at a lower flow rate. That is, the first region includes the first flow passages 11 arranged in such a manner that they are located adjacent to the third flow passages 13 on one side of the lamination direction and not adjacent to the second flow passages 12 on the other side of the lamination direction.

[0036] For example, the first flow passage 11 in the first layer is adjacent to the third flow passage 13 in the second layer only on one side (a bottom side) in the lamination direction, and not adjacent to another flow passage on the other side (a top side) in the lamination direction. Furthermore, the first flow passage 11 in the third layer is adjacent to the third flow passages 13 in the second and fourth layers on both sides (both surface sides) in the lamination direction. As described up to this point, the first region includes a region in which the first flow passage 11 is adjacent only to the third flow passage 13. Thus, the first region is configured so that the engine coolant and the engine oil can exchange heat with each other without being affected by the engine oil.

[0037] The second region includes at least one five-layer flow passage group in which the second flow passage 12, the third flow passage 13, the second flow passage, the first flow passage 11, and the second flow passage 12 are arranged adjacent to each other in sequence, and the respective flow passages are arranged such that the engine coolant and the engine oil exchange heat with each other, and that the engine oil and the engine oil exchange heat with each other. As shown in Fig. 1, the second region in the present embodiment of the invention consists of a total of eight layers, namely the second flow passage 12, the third flow passage 13, the second flow passage 12, the first flow passage 11, the second flow passage 12, the third flow passage 13, the second flow passage 12 and the first flow passage 11, which are arranged in this order from the top.

[0038] As in Fig. As shown in Figure 1, the first region and the second region are adjacent to each other in the lamination direction. Specifically, the first flow passage 11, located in the bottom layer (the fifth layer) of the first region, and the second flow passage 12, located in the top layer (the sixth layer) of the second region, are adjacent to each other.

[0039] In the following, flow directions of the fluids in the respective flow passages of the heat exchanger 1 are determined with reference to Fig. 2. In the drawing, each arrow drawn with a solid line represents a flow direction F11 of the engine coolant in the first flow passages 11, each arrow drawn with a dash-dot-dot-dash line represents a flow direction F12 of the engine oil in the second flow passages 12, and each arrow drawn with a dash-dot-dash line represents a flow direction F13 of the engine oil in the third flow passages 13. Furthermore, “flow direction” in the present embodiment of the invention means a direction from an inflow hole of each of the flow passages toward an outflow hole of each of the flow passages (see Fig. 3 and Fig. 4, which will be described later).

[0040] In addition, Fig. Two black circles on the routes of the arrows drawn with solid lines, the arrows drawn with dash-dot-dot lines, and the arrows drawn with dash-dot-dash lines conceptually represent inflow holes 111, 121, and 131 and outflow holes 112, 122, and 132 for the fluids, respectively. Furthermore, in the drawing, broken lines partially enclosing the routes of the arrows drawn with solid lines, the arrows drawn with dash-dot-dot lines, and the arrows drawn with dash-dot-dash lines conceptually represent interlayer flow connection passages 113, 123, and 133 for the fluids, respectively.

[0041] Furthermore, in the present embodiment of the invention, "inflow hole" means a hole formed most upstream in the flow direction of a fluid among holes through which fluid is introduced into a flow passage. For example, in addition to the first inflow hole 111, a hole (not shown) for introducing the engine coolant from the first flow passage 11 in the third layer into the first flow passage 11 in the first layer through the first flow passage 11 in the first layer is formed. Fig. 2. However, in the present embodiment of the invention, the hole located further upstream (see the black circle) is the first inflow hole 111.

[0042] Furthermore, in the present embodiment of the invention, "discharge hole" means a hole formed most downstream in the flow direction of a fluid among holes through which fluid is discharged from a flow passage. For example, in addition to the first discharge hole 112, a hole (not shown) for discharging the engine coolant from the first flow passage 11 in the first layer to the first flow passage 11 in the third layer through the first flow passage 11 in the first layer is formed. Fig. 2. However, in the present embodiment of the invention, the hole located further downstream (see the black circle) is the first discharge hole 112.

[0043] The first inflow hole 111 for causing the engine coolant flow from the engine or another flow passage into the first flow passage 11 and the first outflow hole 112 for causing the engine coolant flow from the first flow passage 11 to the engine or another flow passage are formed through the two plates 10 (the flat plate 10a and the cup-shaped plate 10b) forming each of the first flow passages 11. As shown particularly in Fig. 2, the first inflow hole 111 and the first outflow hole 112 are formed on both the right and left sides of the plate 10, which forms an upper surface of each of the first flow passages 11. Furthermore, in the drawing, only some of the first inflow holes 111 and the first outflow holes 112 are designated by their reference numerals, respectively, and the other first inflow holes and the other first outflow holes are not assigned reference numerals.

[0044] The engine coolant that flows from the first inflow hole 111 in the first layer (the first flow passage 11) into the first flow passage 11 branches and flows into the first flow passages 11 in the third, fifth, ninth, and thirteenth layers. Subsequently, the engine coolant flows through the first flow passages in the respective layers in a direction perpendicular to the lamination direction (a planar direction of the plates 10), then converges and flows out of the first outflow hole 112 in the first layer (the first flow passage 11) to the outside of the heat exchanger 1 (an engine).

[0045] An interlayer flow communication passage (e.g., cylindrical) that allows fluid to flow into and out of the flow passages located above and below each of the first flow passages 11 is formed in such a manner as to penetrate into the first flow passage 11 between the two plates 10 (the flat plate 10a and the cup-shaped plate 10b) that form the first flow passage 11. For example, an interlayer flow communication passage 123 for the engine oil is formed between the plates 10 that form the first flow passages 11 in the ninth and thirteenth layers. Furthermore, interlayer flow communication passages 133 for the fuel oil are formed between the plates 10 that form the first flow passages 11 in the first, third, fifth, ninth, and thirteenth layers, respectively.

[0046] A second inflow hole 121 for causing the engine oil flow from the engine or another flow passage into the second flow passage 12 and a second outflow hole 122 for causing the engine oil flow from the second flow passage 12 to the engine or another flow passage are formed through the two plates 10 (the cup-shaped plates 10b) forming each of the second flow passages 12. As shown particularly in Fig. 2, the second inflow hole 121 and the second outflow hole 122 are formed on both the right and left sides of the plate 10, which form the bottom surface of the second flow passage 12. Furthermore, only one of the second inflow holes 121 and one of the second outflow holes 122 are designated by their respective reference numerals, and the other second inflow holes 121 and the other second outflow holes 122 are not assigned reference numerals.

[0047] The engine oil that flows from the second inflow hole 121 in the twelfth layer (the second flow passage 12) into the second flow passage 12 via the interlayer flow communication passage 123 branches and flows into the second flow passages 12 in the tenth, eighth, and sixth layers. Subsequently, the engine oil flows through the second flow passages 12 in the respective layers in the direction perpendicular to the lamination direction, then converges and flows out of the second outflow hole 122 in the twelfth layer (the second flow passage 12) via the interlayer flow communication passage 123 to the outside of the heat exchanger 1 (the engine).

[0048] An interlayer flow communication passage (e.g., cylindrical) that allows fluid to flow into and out of the flow passages located above and below each of the second flow passages 12 is formed in such a manner as to penetrate into the second flow passage 12 between the two plates 10 (the cup-shaped plates 10b) that form the second flow passage 12. For example, the interlayer flow communication passage 113 for the engine coolant and the interlayer flow communication passage 133 for the fuel oil are formed between the plates 10 that form each of the second flow passages 12 in the sixth, eighth, tenth, and twelfth layers.

[0049] A third inflow hole 131 for causing the flow of the oil from a transmission or other flow passage into each of the third flow passages 13 and a third outflow hole 132 for causing the flow of the oil from each of the third flow passages 13 to the transmission or other flow passage are formed through the two plates 10 (the cup-shaped plates 10b) forming each of the third flow passages 13. As shown particularly in Fig. 2, the third inflow hole 131 is formed through the plate 10 forming the bottom surface of each of the third flow passages 13. Furthermore, as specifically shown in the drawing, the third outflow hole 132 is formed through the plate 10 forming the top surface of each of the third flow passages 13. Furthermore, in the drawings, only some of the third inflow holes 131 and the third outflow holes 132 are designated by their respective reference numerals, and the other third inflow holes and the other third outflow holes are not assigned reference numerals.

[0050] The GET oil that has flowed from the third inflow hole 131 in the eleventh layer (the third flow passage 13) into the third flow passage 13 via the interlayer flow connection passage 133 branches and flows into the third flow passage 13 in the seventh layer. Subsequently, the GET oil flows through the third flow passages 13 in the respective layers in the direction perpendicular to the lamination direction and then converges. Subsequently, the GET oil branches and flows into the third flow passages 13 in the fourth and second layers, respectively.Subsequently, the get oil flows through the third flow passages 13 in the respective layers in the direction perpendicular to the lamination direction, then flows together and flows out of the third outflow hole 132 in the second layer (the third flow passage 13) via the interlayer flow connection passage 133 to the outside of the heat exchanger 1 (the transmission).

[0051] An interlayer flow communication passage (which is cylindrical, for example), which allows fluid to flow into and out of the flow passages located above and below each of the third flow passages 13, is formed in such a manner as to penetrate into the third flow passage 13 between the two plates 10 (the cup-shaped plates 10b) that form the third flow passage 13. For example, the interlayer flow communication passages 113 for the engine coolant are formed between the plates 10 that respectively form the third flow passages 13 in the eleventh, seventh, fourth, and second layers. Furthermore, the interlayer flow communication passages 123 for the engine oil are formed between the plates 10 that respectively form the third flow passages 13 in the eleventh and seventh layers.

[0052] A relationship of the flow direction of the fluids under the respective flow passages of the heat exchanger 1 will be described below with reference to the Fig. 3 and Fig. 4 described. Fig. Fig. 3 shows, in a projected manner, the positions of the inflow holes and the outflow holes of the respective flow passages in the first region on each of the plates 10 in a plan view along the lamination direction in the heat exchanger 1. In addition, Fig. 4, in a projected manner, the positions of the inflow holes and the outflow holes of the respective flow passages in the second region, on each of the plates 10 in a plan view along the lamination direction, in the heat exchanger 1.

[0053] In addition, the Fig. 3 and Fig. 4. Each of the arrows drawn with solid lines represents a main flow direction F11 (a representative flow direction) of the engine coolant when the first inflow hole 111 and the first outflow hole 112 are connected to each other at the shortest distance. Furthermore, an arrow drawn with a dash-dot-dot line represents a main flow direction F12 of the engine oil when the second inflow hole 121 and the second outflow hole 122 are connected to each other at the shortest distance. Furthermore, each of the arrows drawn with dash-dot-dash lines represents a main flow direction F13 of the engine oil when the third inflow hole 131 and the third outflow hole 132 are connected to each other at the shortest distance.

[0054] Inflow holes and outflow holes for the engine coolant, the engine oil and the coolant oil are formed in each of the plates 10 constituting the respective flow passages of the heat exchanger 1, such that the flow directions of fluids between adjacent ones of the flow passages are opposite to each other in the lamination direction.

[0055] For example in Fig. 3, the respective inflow holes and the respective outflow holes are formed through each of the plates 10 constituting the first flow passage 11 and the third flow passage 13 included in the first region among the respective flow passages of the heat exchanger 1, at such positions that the flow direction F11 of the engine coolant in the first flow passage 11 and the flow direction F13 of the engine oil in the third flow passage 13 are opposite to each other.

[0056] It should be noted here that the above-mentioned state of “opposite each other” means a state in which main lines of flow directions of different fluids cross each other, or a state in which main lines of flow directions of different fluids are opposite each other, as in Fig. 3. In contrast, a state of "non-opposite flow," namely a state in which principal lines of flow directions of different fluids neither cross nor oppose each other, is called a state of "parallel flow."

[0057] It is determined whether the flow direction F11 of the engine coolant and the flow direction F13 of the engine oil are opposite to each other or not depending on a positional relationship between the respective inflow holes and the respective outflow holes formed through each of the plates 10. That is, as shown in Fig. 3, the first inflow hole 111, the first outflow hole 112, the third inflow hole 131, and the third outflow hole 132 are formed through the plate 10 at positions such that a straight line connecting the first inflow hole 111 and the first outflow hole 112 (the main line of the flow direction F11 of the engine coolant) and a straight line connecting the third inflow hole 131 and the third outflow hole 132 (the main line of the flow direction F13 of the engine oil) cross each other.

[0058] Specifically, the first inflow hole 111 and the first outflow hole 112 are formed at widthwise central positions of two opposite sides of each of the plates 10 in a plan view. Furthermore, the third inflow hole 131 and the third outflow hole 132 are formed at diagonal positions through corner portions (round corner portions) of each of the plates 10 in a plan view.

[0059] As described up to this point, in the first region among the respective flow passages of the heat exchanger 1, the main line of the flow direction F11 of the engine coolant and the main line of the flow direction F13 of the coolant oil cross each other, so that the flow direction F11 of the engine coolant and the flow direction F13 of the coolant oil are opposite to each other (see, for example, the first and second layers in Fig. 2). By means of a design in which the flow directions of adjacent fluids are thus opposite to each other, the relative amount of heat that can be exchanged between the adjacent fluids per unit time and the number of opportunities for heat exchange between the adjacent fluids per unit time can be increased compared to the case of parallel flow. Thus, the temperature difference between adjacent fluids can be rapidly reduced, and heat exchange can be carried out more efficiently than in the case of parallel flow.

[0060] As in Fig. 4, the respective inflow holes and the respective outflow holes are formed through each of the plates 10 constituting the first flow passage 11, the second flow passage 12, and the third flow passage 13 included in the second region among the respective flow passages of the heat exchanger 1, at such positions that the flow direction F11 of the engine coolant in the first flow passage 11, the flow direction F12 of the engine oil in the second flow passage 12, and the flow direction F13 of the engine oil in the third flow passage 13 are opposite to each other.

[0061] It is determined whether the flow direction F11 of the engine coolant, the flow direction F12 of the engine oil, and the flow direction F13 of the engine oil are opposite to each other or not depending on a positional relationship between the respective inflow holes and the respective outflow holes formed through each of the plates 10.That is, the first inflow hole 111, the first outflow hole 112, the second inflow hole 121, the second outflow hole 122, the third inflow hole 131, and the third outflow hole 132 are formed through each of the plates 10 at positions such that a straight line connecting the first inflow hole 111 and the first outflow hole 112 (the main line of the flow direction F11 of the engine coolant), a straight line connecting the second inflow hole 121 and the second outflow hole 122 (the main line of the flow direction F12 of the engine oil), and a straight line connecting the third inflow hole 131 and the third outflow hole 132 (the main line of the flow direction F13 of the engine oil) cross each other, as shown in FIG. Fig. 4 shown.

[0062] Specifically, the first inflow hole 111 and the first outflow hole 112 are formed at the center positions in the width direction of two opposite sides of each of the plates 10 in a plan view, respectively. Furthermore, the second inflow hole 121 and the second outflow hole 122 are formed at diagonal positions through corner portions (round corner portions) of each of the plates 10 in a plan view. Furthermore, the third inflow holes 131 and the third outflow holes 132 are formed at diagonal positions through corner portions (round corner portions) of each of the plates 10 in a plan view.

[0063] For example, in the rectangular plate 10, as in Fig. 4, when the second inflow hole 121 and the second outflow hole 122 are formed at diagonal positions through certain ones of four corners, the third inflow hole 131 and the third outflow hole 132 are formed at diagonal positions through certain ones of the four corners in such a manner that they do not overlap with the second inflow hole 121 and the second outflow hole 122, respectively, in a plan view.

[0064] As described up to this point, by arranging the second inflow hole 121, the second outflow hole 122, the third inflow hole 131, and the third outflow hole 132 in the four diagonal corners of each of the plates 10 and ensuring that the main flow direction F12 of the engine oil and the main flow direction F13 of the engine oil cross each other, the crossing amount of the engine oil and the engine oil can be increased compared to the case where the main flow direction line F12 of the engine oil and the main flow direction line F13 of the engine oil do not cross each other (for example, the respective inflow holes and the respective outflow holes are arranged in the four corners such that the main flow direction line F12 and the main flow direction line F13 are parallel to each other).

[0065] As described up to this point, in the second region under the respective flow passages of the heat exchanger 1, the main flow direction line F11 of the engine coolant, the main flow direction line F12 of the engine oil, and the main flow direction line F13 of the engine oil intersect each other. Thus, the flow direction F11 of the engine coolant and the flow direction F12 of the engine oil are opposite to each other (see, for example, the thirteenth and twelfth layers in Fig. 2), and the flow direction F12 of the engine oil and the flow direction F13 of the coolant oil are opposite to each other (see, for example, the twelfth and eleventh layers in the figure). Accordingly, heat exchange can be carried out more efficiently than if the respective flow directions were parallel to each other.

[0066] It should be noted here that the third inflow hole 131 into which the gear oil flows from the transmission is located on the second region side (see the third inflow hole 131 in the eleventh layer), and the third outflow hole 132 from which the gear oil flows from the transmission is located on the first region side (see the third outflow hole 132 in the second layer) in the heat exchanger 1, as shown in Fig. 2. Therefore, the third flow passage 13 included in the second region is arranged upstream of the third flow passage 13 included in the first region in the flow direction of the coolant flowing through the heat exchanger 1. Accordingly, when attention is paid to the heat exchange between the coolant flow and the other fluids in the heat exchanger 1, the coolant flow and the engine coolant first exchange heat with each other in the second region, and then the coolant flow and the engine coolant exchange heat with each other in the first region, as shown in Fig. 2 shown.

[0067] Furthermore, a heat exchange in the above-mentioned second region refers, for example, to a heat exchange in the twelfth layer (the second flow passage 12) to the tenth layer (the second flow passage 12) and a heat exchange of the eighth layer (the second flow passage 12) to the sixth layer (the second flow passage 12) in Fig. 2. In addition, a heat exchange in the above-mentioned first region refers, for example, to a heat exchange of the fifth layer (the first flow passage 11) to the first layer (the first flow passage 11) in the drawing.

[0068] It should be noted here that Fig. Figure 5 shows how the temperatures of the respective fluids change at the time of cold state before completion of warm-up (during the warm-up phase) of an engine and a transmission in a general vehicle. As shown in the figure, overall, among the temperatures of the respective fluids before completion of warm-up, the engine coolant temperature is the highest, the engine oil temperature is the second highest, and the engine oil temperature is the lowest. Under this condition, among the three fluids, it is preferable to first exchange heat between the engine oil and the engine oil, whose temperatures differ from each other by a small amount, and then exchange heat between the engine oil and the engine coolant.The amount of heat accumulated in the coolant can be increased compared to the case where heat is first exchanged between the coolant and the engine coolant, whose temperatures differ by a large amount, and then heat is exchanged between the coolant and the engine coolant by exchanging heat between the respective fluids in this order. Accordingly, the temperature of the coolant can be raised more rapidly and efficiently than in the case of temperature changes occurring in [the original text]. Fig. 5 are shown.

[0069] For example, in Fig. 5, the temperature of the GET oil is raised to approximately 85°C at a time of 1800 s. However, the temperature of the GET oil can also be raised to approximately 85°C at a time before 1800 s by first exchanging heat between the GET oil and the ENGINE oil, and then exchanging heat between the GET oil and the ENGINE coolant, as described above. Furthermore, the warm-up phase of the transmission is assisted, and the amount of friction is reduced by exchanging heat between the respective fluids in the above-mentioned order. Therefore, fuel economy is also improved.

[0070] In addition, Fig. 6 exemplary temperatures of the respective fluids at the time of warm-up after warm-up of an engine and a transmission in a general vehicle. As shown in the figure, among the temperatures of the respective fluids, in the case of the vehicle traveling at high speed or traveling uphill (traveling with a high load), the temperature of the GET oil is the highest, the temperature of the ENGINE oil is the second highest, and the temperature of the ENGINE coolant is the lowest. Under this condition, it is preferable that, among the three fluids, heat is first exchanged between the GET oil and the ENGINE oil, whose temperatures differ from each other by a small value, and then heat is exchanged between the GET oil and the ENGINE coolant.The amount of heat released by the get oil can be made to a large value, and the temperature of the get oil can be efficiently lowered by exchanging heat among the respective fluids in this order.

[0071] For the reason stated above, in the heat exchanger 1, the third flow passage 13 included in the second region is arranged upstream of the third flow passage 13 included in the first region in the flow direction of the GET oil, as described above. Thus, heat is first exchanged between the GET oil and the MOT oil, whose temperatures differ from each other by a small amount, in the second region, and then heat is exchanged between the GET oil that has exchanged heat with the MOT oil and the MOT coolant in the first region. In this way, the temperature of the GET oil, whose flow rate is low, can be efficiently raised or lowered.

[0072] The heat exchanger 1 configured as described above has the region in which the first flow passage 11 is adjacent only to the second flow passage 12 and the third flow passage 13 through which the fluid with a lower flow rate (the third flow passage 13) flows in the lamination direction. Therefore, in this region, heat can be exchanged between the fluid whose flow rate is low (the GET oil) and the engine coolant without being affected by the other fluid (the GET oil). Accordingly, even if the heat exchanger 1 is mounted in a vehicle having a powertrain in which the GET oil flow rate is lower than the GET oil flow rate, the amount of heat exchange between the GET oil and the engine coolant can be increased, and the GET oil temperature can be sufficiently raised or lowered.

[0073] In the heat exchanger of the above-mentioned JP 2013-113578 A, the three fluids exchange heat with each other simultaneously. Therefore, it is difficult, for example, to adjust the amount of heat exchange between the GET oil and the ENGINE coolant to an optimal value (a desired specification). On the other hand, in the heat exchanger 1 according to the present embodiment of the invention, the specification of the amount of heat exchange between the GET oil and the ENGINE coolant can be easily changed, for example, by increasing or decreasing the number of repetitions of the first flow passages 11 and the third flow passages 13 in the first region. That is, the heat exchanger 1 is designed as a three-phase heat exchanger, but has the first region in which only the two fluids exchange heat with each other.Therefore, the amount of heat exchange between the two fluids can be easily adjusted by increasing or decreasing the number of layers of the respective flow passages in this region.

[0074] The vehicle heat exchanger according to the second embodiment of the invention is designed to be installed, for example, in a vehicle having a powertrain in which the flow rate of the engine oil is lower than the flow rates of the engine coolant and the coolant oil. This vehicle heat exchanger primarily aims to increase the amount of heat exchange of the engine oil, whose flow rate is low.

[0075] As in Fig. 7, a heat exchanger 1A for a vehicle is formed by laminating the plurality of plates 10. In this respect, the heat exchanger 1A is identical to the heat exchanger for the vehicle according to the above-described first embodiment of the invention. On the other hand, as shown in the drawing, the heat exchanger 1A differs from the heat exchanger for the vehicle according to the above-described first embodiment of the invention in the arrangement of flow passages in the first region and the second region. Moreover, in the following description, components that are the same as those of the first embodiment of the invention are denoted by the respective reference numerals, and their description will be omitted.

[0076] As in Fig. As shown in Figure 7, the heat exchanger 1A consists of a total of thirteen layers. The first flow passages 11 are arranged in the first, third, fifth, ninth, and thirteenth layers, the second flow passages 12 are arranged in the second, fourth, seventh, and eleventh layers, and the third flow passages 13 are arranged in the sixth, eighth, tenth, and twelfth layers. As described up to this point, in the present embodiment of the invention, the positions where the second flow passages 12 are arranged and the positions where the third flow passages 13 are arranged are respectively reversed from those in the first embodiment of the invention.

[0077] The heat exchanger 1A has two regions, namely a first region and a second region, as regions where multiple fluids exchange heat with each other. The first region aims to increase the amount of heat exchange between the engine oil and the engine coolant. The first region includes at least a three-layer flow passage group in which the first flow passage 11, the second flow passage 12, and the first flow passage 11 are arranged adjacent to each other in sequence. The first flow passages 11 and the second flow passages 12 are alternately laminated to each other in the lamination direction. As shown in Fig. 7, the first region in the present embodiment of the invention consists of a total of five layers, namely the first flow passage 11, the second flow passage 12, the first flow passage 11, the second flow passage 12 and the first flow passage 11, which are arranged in this order from the top.

[0078] In addition, as in Fig. As shown in Figure 7, the first region includes a region in which the first flow passage is adjacent only to the second flow passage 12 and the third flow passage 13 through which the fluid flows at a lower flow rate. That is, the first region includes the first flow passage 11 arranged to be adjacent to the second flow passage 12 on one side in the lamination direction and not adjacent to the third flow passage 13 on the other side of the lamination direction.

[0079] For example, the first flow passage 11 in the first layer is adjacent to the second flow passage 12 in the second layer only on one side of the lamination direction (the bottom side), and not adjacent to another flow passage on the other side of the lamination direction (the top side). Furthermore, the first flow passage 11 in the third layer is adjacent to the second flow passages 12 in the second and fourth layers on both sides of the lamination direction (both side surfaces). As described up to this point, the first region includes a region in which the first flow passage 11 is adjacent only to the second flow passage 12. Thus, the heat exchanger 1A is configured so that the engine coolant and the engine oil can exchange heat with each other without being affected by the engine oil.

[0080] The second region includes at least one five-layer flow passage group in which the third flow passage 13, the second flow passage 12, the third flow passage 13, the first flow passage 11, and the third flow passage 13 are arranged adjacent to each other in sequence. The respective flow passages are arranged such that the engine coolant and the coolant oil exchange heat with each other, and the engine oil and the coolant oil exchange heat with each other. As shown in Fig. 7, the second region in the present embodiment of the invention consists of a total of eight layers: the third flow passage 13, the second flow passage 12, the third flow passage 13, the first flow passage 11, the third flow passage 13, the second flow passage 12, the third flow passage 13 and the first flow passage 11, which are arranged in this order from the top.

[0081] As in Fig. As shown in Figure 7, the first region and the second region are adjacent to each other in the lamination direction. Specifically, the first flow passage 11, located in the lowermost layer of the first region (the fifth layer), and the third flow passage 13, located in the uppermost layer of the second region (the sixth layer), are adjacent to each other.

[0082] Flow directions of the fluids in the respective flow passages of the heat exchanger 1A are described below with reference to Fig. 8 described.

[0083] The engine coolant that has flowed from the first inflow hole 111 in the first layer (the first flow passage 11) into the first flow passage 11 branches and flows into the first flow passages 11 in the third, fifth, ninth, and thirteenth layers. Subsequently, the engine coolant flows through the first flow passages in the respective layers in the direction perpendicular to the lamination direction, then converges and flows out of the first outflow hole 112 in the first layer (the first flow passage 11) to the outside of the heat exchanger 1A (the engine).

[0084] The engine oil that has flowed from the second inflow hole 121 in the eleventh layer (the second flow passage 12) into the second flow passage 12 via the interlayer flow communication passage 123 branches and flows into the second flow passages 12 in the seventh, fourth, and second layers. Subsequently, the engine oil flows through the second flow passages 12 in the respective layers in the direction perpendicular to the lamination direction, then converges and flows out of the second outflow hole 122 in the eleventh layer (the second flow passage 12) via the interlayer flow communication passage 123 to the outside of the heat exchanger 1A (the engine).

[0085] The GET oil that has flowed from the third inflow hole 131 in the twelfth layer (the third flow passage 13) into the third flow passage 13 via the interlayer flow connection passage 133 branches and flows into the third flow passage 13 in the tenth layer. Then, the GET oil flows through the third flow passages 13 in the respective layers in the direction perpendicular to the lamination direction and then converges. Subsequently, the GET oil branches and flows into the third flow passages 13 in the eighth and sixth layers. Subsequently, the get oil flows through the third flow passages 13 in the respective layers in the direction perpendicular to the lamination direction, then flows together and flows out of the third discharge hole 132 in the sixth layer (the third flow passage 13) via the interlayer flow communication passage 133 to the outside of the heat exchanger 1A (the transmission).

[0086] A relationship in the flow direction of fluid among the respective flow passages of the heat exchanger 1A will be described below with reference to the Fig. 9 and Fig. 10 described. Fig. Fig. 9 shows, in a projected manner, the positions of the inflow holes and outflow holes of the respective flow passages in the first region on the plate 10 in a plan view along the lamination direction in the heat exchanger 1A. In addition, Fig. 10, in a projected manner, the positions of the inflow holes and outflow holes of the respective flow passages in the second region, on the plate 10 in a plan view along the lamination direction, in the heat exchanger 1A.

[0087] As in Fig. 9, the respective inflow holes and the respective outflow holes are formed through each of the plates 10 constituting the first flow passage 11 and the second flow passage 12 included in the first region among the respective flow passages of the heat exchanger 1A, such that the flow direction F11 of the engine coolant in the first flow passage 11 and the flow direction F12 of the engine oil in the second flow passage 12 are opposite to each other.

[0088] As in Fig. 9, the first inflow hole 111, the first outflow hole 112, the second inflow hole 121, and the second outflow hole 122 are formed through each of the plates 10 such that a straight line connecting the first inflow hole 111 and the first outflow hole 112 (the main line of the flow direction F11 of the engine coolant) and a straight line connecting the second inflow hole 121 and the second outflow hole 122 (the main line of the flow direction F12 of the engine oil) cross each other.

[0089] Specifically, the first inflow hole 111 and the first outflow hole 112 are formed at widthwise central positions of two opposite sides of each of the plates 10 in a plan view. Furthermore, the second inflow hole 121 and the second outflow hole 122 are formed at diagonal positions through corner portions (round corner portions) of each of the plates 10 in a plan view.

[0090] As described up to this point, in the first region among the respective flow passages of the heat exchanger 1A, the main line of the flow direction F11 of the engine coolant and the main line of the flow direction F12 of the engine oil cross each other, so that the flow direction F11 of the engine coolant and the flow direction F12 of the engine oil are opposite to each other (see, for example, the first and second layers in Fig. 8). Accordingly, heat exchange can be carried out more efficiently than if the flow directions were parallel to each other.

[0091] As in Fig. 10, the respective inflow holes and the respective outflow holes are formed through each of the plates 10 constituting the first flow passage 11, the second flow passage 12, and the third flow passage 13 included in the second region among the respective flow passages of the heat exchanger 1A, at such positions that the flow direction F11 of the engine coolant in the first flow passage 11, the flow direction F12 of the engine oil in the second flow passage 12, and the flow direction F13 of the engine oil in the third flow passage 13 are opposite to each other. Moreover, the positions of the respective inflow holes and the respective outflow holes shown in the drawing are the same as those of the above-described Fig. 4 are identical, so their detailed description is omitted.

[0092] In the second region under the respective flow passages of the heat exchanger 1A, the main flow direction line F11 of the engine coolant, the main flow direction line F12 of the engine oil, and the main flow direction line F13 of the coolant oil intersect each other. Thus, the flow direction F11 of the engine coolant and the flow direction F13 of the coolant oil are opposite to each other (see, for example, the ninth and eighth layers in Fig. 8), and the flow direction F12 of the engine oil and the flow direction F13 of the engine oil are opposite to each other (see, for example, the twelfth and eleventh layers in Fig. 8). Accordingly, heat exchange can be carried out more efficiently than if the flow directions were parallel to each other.

[0093] The heat exchanger 1A configured as described above has the region where the first flow passage 11 is adjacent to the second flow passage 12 in the lamination direction. Therefore, in this region, heat can be exchanged between the engine oil and the engine coolant without being affected by the coolant. Accordingly, even if the heat exchanger 1A is mounted in a vehicle having a powertrain in which the flow rate of the engine oil is lower than the flow rate of the coolant, the amount of heat exchange between the engine oil and the engine coolant can be increased, and the temperature of the engine oil can be sufficiently raised or lowered.

[0094] Furthermore, in the heat exchanger of the above-mentioned JP 2013-113578 A, the three fluids exchange heat with each other simultaneously. Therefore, it is difficult, for example, to adjust the amount of heat exchange between the engine oil and the engine coolant to an optimal value (a desired specification). On the other hand, in the heat exchanger 1A according to the present embodiment of the invention, the specification of the amount of heat exchange between the engine oil and the engine coolant can be easily changed, for example, by increasing or decreasing the number of repetitions of the first flow passages 11 and the second flow passages 12 in the first region.

[0095] The heat exchanger for the vehicle according to the third embodiment of the invention aims at increasing the amount of heat exchange between the fluid whose flow rate is low (the GET oil or the ENGINE oil) and the ENGINE coolant as in the above-described first and second embodiments of the invention, and at changing the specification of the amount of heat exchange among the respective fluids more easily than in the above-described first and second embodiments of the invention.

[0096] As in Fig. 11, a heat exchanger 1B is formed by laminating the plurality of plates 10. In this respect, the heat exchanger 1B is identical to the heat exchangers 1 and 1A according to the above-described first and second embodiments of the invention. On the other hand, as shown in the drawing, the heat exchanger 1B differs from the heat exchangers according to the above-described first and second embodiments of the invention in the number of regions into which the respective flow passages are divided. Moreover, in the following description, components that are the same as those of the first and second embodiments of the invention are denoted by the reference numerals, respectively, and their description will be omitted.

[0097] As in Fig. As shown in Figure 11, the heat exchanger 1B consists of a total of twelve layers. The first flow passages 11 are arranged in the first, third, fifth, and seventh layers, the second flow passages 12 are arranged in the sixth, eighth, tenth, and twelfth layers, and the third flow passages 13 are arranged in the second, fourth, ninth, and eleventh layers.

[0098] The heat exchanger 1B has three regions, namely a first region, a second region, and a third region, as regions where multiple fluids exchange heat with each other. The first region is a region aimed at increasing the amount of heat exchange between the engine oil and the engine coolant. The first region has at least a three-layer flow passage group in which the first flow passage 11, the third flow passage 13, and the first flow passage 11 are arranged adjacent to each other in sequence, and the first flow passages 11 and the third flow passages 13 are arranged alternately in the lamination direction. As shown in Fig. 11, the first region in the present embodiment of the invention consists of a total of four layers, namely the first flow passage 11, the third flow passage 13, the first flow passage 11 and the third flow passage 13, which are arranged in this order from the top.

[0099] In addition, as in Fig. 11, the first region includes a region in which the first flow passage 11 is located only adjacent to the second flow passage 12 and the third flow passage 13 through which the fluid flows at a lower flow rate. That is, the first region includes the first flow passage 11 arranged to be adjacent to the third flow passage 13 on one side of the lamination direction and not adjacent to the second flow passage 12 on the other side of the lamination direction.

[0100] For example, the first flow passage 11 in the first layer is adjacent to the third flow passage 13 in the second layer only on one side of the lamination direction (the bottom side), and not adjacent to another flow passage on the other side of the lamination direction (the top side). Furthermore, the first flow passage 11 in the third layer is adjacent to the third flow passages 13 in the second and fourth layers on both sides of the lamination direction (on both side surfaces). As described up to this point, the first region includes a region in which the first flow passage 11 is adjacent only to the third flow passage 13. Thus, the heat exchanger is configured so that the engine coolant and the engine oil can exchange heat with each other without being affected by the engine oil.

[0101] The second region comprises at least one three-layer flow passage group in which the third flow passage 13, the second flow passage 12, and the third flow passage 13 are arranged adjacent to each other in sequence, and the second flow passages 12 and the third flow passages 13 are arranged alternately in the lamination direction. As shown in Fig. 11, the second region in the present embodiment of the invention consists of a total of four layers, namely the third flow passage 13, the second flow passage 12, the third flow passage 13 and the second flow passage 12, which are arranged in this order from the top.

[0102] The third region comprises at least one three-layer flow passage group in which the second flow passage 12, the first flow passage 11, and the second flow passage 12 are arranged adjacent to each other in sequence, and the first flow passages 11 and the second flow passages 12 are arranged alternately in the lamination direction. As shown in Fig. 11, the third region in the present embodiment of the invention consists of a total of four layers, namely the first flow passage 11, the second flow passage 12, the first flow passage 11 and the second flow passage 12, which are arranged in this order from the top.

[0103] In addition, as in Fig. 11, the third region includes the first flow passage 11 arranged to be adjacent to the second flow passage 12 on one side of the lamination direction and not adjacent to the third flow passage 13 on the other side of the lamination direction.

[0104] For example, the first flow passage 11 in the seventh layer is adjacent to the second flow passages 12 in the sixth and eighth layers, respectively, on both sides in the lamination direction (on both side surfaces). As described up to this point, the third region has a region in which the first flow passage 11 is adjacent only to the second flow passage 12. Thus, the heat exchanger is configured so that the engine coolant and the engine oil can exchange heat with each other without being affected by the engine oil.

[0105] As in Fig. As shown in Figure 11, the first region, the third region, and the second region are arranged adjacent to each other in the lamination direction. Specifically, the third flow passage 13 located in the lowest layer of the first region (the fourth layer) and the first flow passage 11 located in the uppermost layer of the third region (the fifth layer) are arranged adjacent to each other, and the second flow passage 12 located in the lowest layer of the third region (the eighth layer) and the third flow passage 13 located in the uppermost layer of the second region (the ninth layer) are arranged adjacent to each other.

[0106] Flow directions of the fluids in the respective flow passages of the heat exchanger 1B are described below with reference to Fig. 12 described.

[0107] The engine coolant that has flowed from the first inflow hole 111 in the first layer (the first flow passage 11) into the first flow passage 11 branches and flows into the first flow passages 11 in the third, fifth, and seventh layers. Subsequently, the engine coolant flows through the first flow passages 11 in the respective layers in the direction perpendicular to the lamination direction, then converges and flows out of the first outflow hole 112 in the first layer (the first flow passage 11) to the outside of the heat exchanger 1B (the engine).

[0108] The engine oil that has flowed from the second inflow hole 121 in the twelfth layer (the second flow passage 12) into the second flow passage 12 branches and flows into the second flow passages 12 in the tenth, eighth, and sixth layers. Subsequently, the engine oil flows through the second flow passages 12 in the respective layers in the direction perpendicular to the lamination direction, then converges and flows out of the second outflow hole 122 in the twelfth layer (the second flow passage 12) to the outside of the heat exchanger 1B (the engine).

[0109] The GET oil that has flowed from the third inflow hole 131 in the eleventh layer (the third flow passage 13) into the third flow passage 13 via the interlayer flow connection passage 133 branches and flows into the third flow passage 13 in the ninth layer. Then, the GET oil flows through the third flow passages 13 in the respective layers in the direction perpendicular to the lamination direction and then converges. Subsequently, the GET oil branches and flows into the third flow passages 13 in the fourth and second layers. Subsequently, the get oil flows through the third flow passages in the respective layers in the direction perpendicular to the lamination direction, then flows together and flows out of the third outflow hole 132 in the second layer (the third flow passage 13) via the interlayer flow connection passage 133 to the outside of the heat exchanger 1B (the transmission).

[0110] A relationship in the flow direction of the fluids under the respective flow passages of the heat exchanger 1B will be described below with reference to the Fig. 13 to 15 described. Fig. Fig. 13 shows, in a projected manner, the positions of the inflow holes and outflow holes of the respective flow passages in the first region on each of the plates 10 in a plan view along the lamination direction in the heat exchanger 1B. In addition, Fig. 14 shows, in a projected manner, the positions of the inflow holes and outflow holes of the respective flow passages in the third region on each of the plates 10 in a plan view along the lamination direction in the heat exchanger 1B. In addition, Fig. 15 shows, in a projected manner, the positions of the inflow holes and outflow holes of the respective flow passages in the second region on each of the plates 10 in a plan view along the lamination direction in the heat exchanger 1B.

[0111] As in Fig. 13, the respective inflow holes and the respective outflow holes are formed through each of the plates 10 constituting the first flow passage 11 and the third flow passage 13 included in the first region among the respective flow passages of the heat exchanger 1B, at such positions that the flow direction F11 of the engine coolant in the first flow passage 11 and the flow direction F13 of the engine oil in the third flow passage 13 are opposite to each other. Moreover, the positions of the respective inflow holes and outflow holes shown in the drawing are identical to those shown in the above-described Fig. 3, so their detailed description is omitted.

[0112] In the first region among the respective flow passages of the heat exchanger 1B, the main line of the flow direction F11 of the engine coolant and the main line of the flow direction F13 of the coolant oil cross each other, so that the flow direction F11 of the engine coolant and the flow direction F13 of the coolant oil are opposite to each other (see, for example, the third and second layers in Fig. 12). Accordingly, the heat exchange can be carried out more efficiently than in the case where the flow directions are parallel to each other.

[0113] As in Fig. 14, the respective inflow holes and the respective outflow holes are formed through each of the plates 10 constituting the first flow passage 11 and the second flow passage 12 included in the third region among the respective flow passages of the heat exchanger 1B, at such positions that the flow direction F11 of the engine coolant in the first flow passage 11 and the flow direction F12 of the engine oil in the second flow passage 12 are opposite to each other.

[0114] As in Fig. 14, the first inflow hole 111, the first outflow hole 112, the second inflow hole 121, and the second outflow hole 122 are formed through each of the plates 10 at positions such that a straight line connecting the first inflow hole 111 and the first outflow hole 112 (the main line of the flow direction F11 of the engine coolant) and a straight line connecting the second inflow hole 121 and the second outflow hole 122 (the main line of the flow direction F12 of the engine oil) cross each other.

[0115] Specifically, the first inflow hole 111 and the first outflow hole 112 are formed at widthwise central positions of two opposite sides of each of the plates 10 in a plan view. Furthermore, the second inflow hole 121 and the second outflow hole 122 are formed at diagonal positions through corner portions (round corner portions) of each of the plates 10 in a plan view.

[0116] As described up to this point, in the third region among the respective flow passages of the heat exchanger 1B, the main line of the flow direction F11 of the engine coolant and the main line of the flow direction F12 of the engine oil cross each other, so that the flow direction F11 of the engine coolant and the flow direction F12 of the engine oil are opposite to each other (see, for example, the seventh and sixth layers in Fig. 12). Accordingly, the heat exchange can be carried out more efficiently than in the case where the flow directions are parallel to each other.

[0117] As in Fig. 15, the respective inflow holes and the respective outflow holes are formed through each of the plates 10 constituting the second flow passage 12 and the third flow passage 13 included in the second region among the respective flow passages of the heat exchanger 1B, at such positions that the flow direction F12 of the engine oil in the second flow passage 12 and the flow direction F13 of the coolant oil in the third flow passage 13 are opposite to each other.

[0118] As in Fig. 15, the second inflow hole 121, the second outflow hole 122, the third inflow hole 131, and the third outflow hole 132 are formed through each of the plates 10 at positions such that a straight line connecting the second inflow hole 121 and the second outflow hole 122 (the main line of the flow direction F12 of the engine oil) and a straight line connecting the third inflow hole 131 and the third outflow hole 132 (the main line of the flow direction F13 of the engine oil) cross each other.

[0119] Specifically, the second inflow hole 121 and the second outflow hole 122 are formed at diagonal positions through corner portions (round corner portions) of each of the plates 10 in a plan view. Furthermore, the third inflow hole 131 and the third outflow hole 132 are formed at diagonal positions through corner portions (round corner portions) of each of the plates 10 in a plan view.

[0120] As described up to this point, in the second region under the respective flow passages of the heat exchanger 1B, the main line of the flow direction F12 of the engine oil and the main line of the flow direction F13 of the coolant oil intersect each other. Thus, the flow direction F12 of the engine oil and the flow direction F13 of the coolant oil are opposite to each other (see, for example, the tenth and eleventh layers in Fig. 12). Accordingly, the heat exchange can be carried out more efficiently than in the case where the flow directions are parallel to each other.

[0121] The heat exchanger 1B configured as described above has the region where the first flow passage 11 is adjacent to the third flow passage 13 in the lamination direction. Therefore, in this region, heat can be exchanged between the GET oil and the engine coolant without being affected by the engine oil. Accordingly, even if the heat exchanger 1B is mounted in a vehicle having a powertrain in which the flow rate of the GET oil is lower than the flow rate of the engine oil, the amount of heat exchange between the GET oil and the engine coolant can be increased, and the temperature of the GET oil can be sufficiently raised or lowered.

[0122] Furthermore, in the heat exchanger 1B according to the present embodiment of the invention as well as those according to the above-described first and second embodiments of the invention, the specification of the amount of heat exchange between the engine oil and the engine coolant can be easily changed by increasing or decreasing the number of repetition of the first flow passages 11 and the third flow passages 13 in the first region, and the specification of the amount of heat exchange between the engine oil and the engine coolant can be easily changed by increasing or decreasing the number of repetition of the first flow passages 11 and the second flow passages 12 in the first region.

[0123] The heat exchangers according to the invention have been described above specifically with reference to the modes for carrying out the invention. However, the spirit of the invention is not limited to the above description, but should be interpreted broadly based on the claims. Furthermore, it is to be understood that the spirit of the invention also encompasses various changes, modifications, and the like based on the above description.

[0124] For example, as in Fig. As shown in Figure 1, the above-described heat exchanger 1 consists of a total of thirteen layers, the first region consists of a total of five layers, and the second region consists of a total of eight layers. However, the number of laminated flow passages of the heat exchanger 1 can be appropriately changed according to a desired specification of the amount of heat exchange. That is, as long as the first region in the heat exchanger 1 includes at least a three-layer flow passage group in which the first flow passage 11, the third flow passage 13, and the first flow passage 11 are arranged adjacent to each other in sequence, the number of laminated flow passages is not particularly limited.Furthermore, as long as the second region in the heat exchanger 1 comprises at least one five-layer flow passage group in which the second flow passage 12, the third flow passage 13, the second flow passage 12, the first flow passage 11 and the second flow passage 12 are arranged adjacent to each other in sequence, the number of laminated flow passages is not particularly limited.

[0125] In addition, as in Fig. As shown in Fig. 7, the above-described heat exchanger 1A consists of a total of thirteen layers, the first region consists of a total of five layers, and the second region consists of a total of eight layers. However, the number of laminated flow passages of the heat exchanger 1A can be appropriately changed according to a desired specification of the amount of heat exchange. That is, as long as the first region in the heat exchanger 1A includes at least a three-layer flow passage group in which the first flow passage 11, the second flow passage 12, and the first flow passage 11 are arranged adjacent to each other in sequence, the number of laminated flow passages is not particularly limited.Furthermore, as long as the second region in the heat exchanger 1A includes at least a five-layer flow passage group in which the third flow passage 13, the second flow passage 12, the third flow passage 13, the first flow passage 11, and the third flow passage 13 are arranged adjacent to each other in sequence, the number of laminated flow passages is not particularly limited.

[0126] In addition, as in Fig.As shown in FIG. 11, the above-described heat exchanger 1B consists of a total of twelve layers, and each of the first region, the second region, and the third region consists of a total of four layers. However, the number of laminated flow passages of the heat exchanger 1B can be appropriately changed according to a desired specification of the amount of heat exchange. That is, as long as the first region in the heat exchanger 1B includes at least a three-layer flow passage group in which the first flow passage 11, the third flow passage 13, and the first flow passage 11 are arranged adjacent to each other in sequence, the number of laminated flow passages is not particularly limited.Furthermore, as long as the second region in the heat exchanger 1B includes at least one three-layer flow passage group in which the third flow passage 13, the second flow passage 12, and the third flow passage 13 are arranged adjacent to each other in sequence, the number of laminated flow passages is not particularly limited. Furthermore, as long as the third region in the heat exchanger 1B includes at least one three-layer flow passage group in which the first flow passage 11, the second flow passage 12, and the first flow passage 11 are arranged adjacent to each other in sequence, the number of laminated flow passages is not particularly limited.

Claims

[1] Heat exchanger (1) for a vehicle, wherein: the vehicle comprises a drive train configured such that an engine coolant, an engine oil, and a transmission oil flow through the drive train, and that a flow rate of the engine oil and a flow rate of the transmission oil are different from each other, the heat exchanger (1) comprises: a first flow passage (11) through which the engine coolant flows, a second flow passage (12) through which the engine oil flows, and a third flow passage (13) through which the transmission oil flows, the first flow passage (11), the second flow passage (12) and the third flow passage (13) are divided by laminating several plates (10), the heat exchanger (1) is designed such that heat exchange is carried out between the respective flow passages arranged side by side in a lamination direction of the plurality of plates (10), the heat exchanger (1) comprises a region in which the first flow passage (11) is located only adjacent to the third flow passage (13), the drive train is designed so that a flow rate of the transmission oil is lower than a flow rate of the engine oil, the heat exchanger (1) comprises a first region and a second region, such that the first region comprises at least one flow passage group in which the first flow passage (11), the third flow passage (13) and the first flow passage (11) are arranged next to one another in sequence, and a region in which the first flow passage (11) is arranged only next to the third flow passage (13), and the second region comprises at least one flow passage group in which the second flow passage (12), the third flow passage (13), the second flow passage (12), the first flow passage (11) and the second flow passage (12) are arranged next to one another in sequence, and the first region and the second region are adjacent to each other in the lamination direction. [2] Heat exchanger (1) for a vehicle, wherein: the vehicle comprises a drive train configured such that an engine coolant, an engine oil, and a transmission oil flow through the drive train, and that a flow rate of the engine oil and a flow rate of the transmission oil are different from each other, the heat exchanger (1) comprises: a first flow passage (11) through which the engine coolant flows, a second flow passage (12) through which the engine oil flows, and a third flow passage (13) through which the transmission oil flows, the first flow passage (11), the second flow passage (12) and the third flow passage (13) are divided by laminating a plurality of plates (10), the heat exchanger (1) is designed such that heat exchange is carried out between the respective flow passages arranged side by side in a lamination direction of the plurality of plates (10), the heat exchanger (1) comprises a region in which the first flow passage (11) is located only adjacent to the second flow passage (12), the drive train is designed such that a flow rate of the engine oil is lower than a flow rate of the transmission oil, and the heat exchanger (1) comprises a first region and a second region, such that the first region comprises at least one flow passage group in which the first flow passage (11), the second flow passage (12) and the first flow passage (11) are arranged next to one another in sequence, and a region in which the first flow passage (11) is arranged only next to the second flow passage (12), and the second region comprises at least one flow passage group in which the third flow passage (13), the second flow passage (12), the third flow passage (13), the first flow passage (11) and the third flow passage (13) are arranged next to one another in sequence, and the first region and the second region are adjacent to each other in the lamination direction. [3] Heat exchanger (1) according to claim 1, wherein: the third flow passage (13) included in the second region is arranged upstream of the third flow passage (13) included in the first region in a flow direction of the transmission oil flowing through the heat exchanger (1). [4] Heat exchanger (1) according to one of claims 1 to 3, wherein: the plates (10) forming the first flow passage (11), the second flow passage (12) and the third flow passage (13) are each provided with inflow holes (111, 121, 131) and outflow holes (112, 122, 132) for the engine coolant, the engine oil and the transmission oil, such that flow directions of fluids flowing through adjacent ones of the flow passages are opposite to each other. [5] Heat exchanger (1) according to claim 4, wherein: the inflow holes (111, 121, 131) and the outflow holes (112, 122, 132) are each arranged through the plates (10) at such positions that a straight line connecting the inflow holes (121) and the outflow holes (122) of the second flow passage (12) and a straight line connecting the inflow holes (131) and the outflow holes (132) of the third flow passage (13) cross each other.

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