Structure of inflow part of storage tank

Abstract

The invention provides a structure of an inflow part of a storage tank. The storage tank is arranged in the cooling liquid circulation circuit, and when the side, closer to the storage tank body, of the inflow part is set as one end side, and the side, farther from the storage tank body, of the inflow part is set as the other end side, the flow channel area of the one end side is larger than that of the flow channel area of the other end side of the inflow part. The flow channel shape inside the inflow portion has a tapered shape in which the flow channel area gradually increases from the other end side toward the one end side.

Description

Technical Field

[0001] The present invention relates to a structure of an inflow portion of a storage tank provided in a coolant circulation circuit. Background Art

[0002] In the past, as disclosed in Japanese Patent Application Laid-Open No. 2022-53938, a coolant circulation circuit for cooling a device (heat generating component) accompanied by heat generation is provided in a vehicle, and the device is cooled by the coolant circulating in the coolant circulation circuit. In addition, a storage tank is provided in the coolant circulation circuit. The storage tank is used to replenish the coolant to the coolant circulation circuit, and has the function of absorbing the volume change caused by the thermal expansion of the coolant.

[0003] When air is mixed into the coolant in the storage tank, the air may flow into the coolant circulation circuit, thereby deteriorating the cooling efficiency of the equipment.

[0004] As technologies proposed in view of this, Japanese Patent Laid-Open No. 2021-169815 and Japanese Patent Laid-Open No. 2022-149429 are currently proposed. Japanese Patent Laid-Open No. 2021-169815 discloses a technology in which a structure is adopted to rotate the coolant in a storage tank, thereby separating the air mixed in the coolant by centrifugal force. In addition, in Japanese Patent Laid-Open No. 2022-149429, a partition plate having a hole at the bottom is provided in the storage tank, and the air mixed in the coolant is separated while the coolant is retained between the partition plates. Summary of the invention

[0005] However, these patent documents all disclose technologies for separating air mixed in the coolant.

[0006] The inventors of the present invention have considered that preventing air from being mixed into the coolant from the beginning is more effective in suppressing deterioration in cooling efficiency than separating the air mixed into the coolant.

[0007] Figure 6This is a cross-sectional view of the vicinity of a storage tank a for explaining the situation in which air (bubbles) are mixed into the coolant b in the storage tank a. An inflow portion e formed by a straight pipe is provided at the lower portion of the side wall d of the storage tank a, and an outflow portion g is provided on the bottom plate f of the storage tank a. The coolant b that flows into the storage tank a through the inflow portion e from the coolant circulation loop (not shown) collides with the side wall h of the storage tank a (the side wall opposite to the side wall d where the inflow portion e is provided) and the streamlines are directed upward. As a result, the liquid level of the coolant b fluctuates (fluctuates). The higher the flow rate of the coolant b that flows into the storage tank a, the greater the fluctuation of the liquid level. In this way, since the liquid level of the coolant b fluctuates, the air i existing in the upper layer of the storage tank a is drawn into the coolant b, so that the air c is mixed into the coolant b. Furthermore, when the air c flows out from the outflow portion g into the coolant circulation circuit and circulates in the coolant circulation circuit, the cooling efficiency will be deteriorated. Therefore, in order to suppress the deterioration of the cooling efficiency, it is more effective to prevent the air c from mixing into the coolant b in the storage tank a.

[0008] The present invention has been made in view of this point, and an object of the present invention is to provide a structure of an inflow portion of a reservoir tank that can suppress mixing of air into coolant.

[0009] The solution of the present invention for achieving the above object is based on the structure of the inlet portion of the storage tank provided in the coolant circulation circuit. The structure of the inlet portion of the storage tank is characterized in that, when the side closer to the storage tank body in the flow direction of the coolant in the inlet portion is set as one end side and the side farther from the storage tank body is set as the other end side, the flow channel area of ​​the one end side in the inlet portion is larger than the flow channel area of ​​the other end side.

[0010] According to this specific matter, when the coolant flows from the coolant circulation loop through the inflow portion into the storage tank (storage tank body), the flow channel area of ​​one end side in the inflow portion is larger than the flow channel area of ​​the other end side. The other end side is the side farther from the storage tank body in the flow direction of the coolant. The one end side is the side closer to the storage tank body in the flow direction of the coolant. As a result, the flow rate of the coolant can be reduced while suppressing the decrease in the flow rate in the inflow portion (the amount of coolant flowing into the storage tank body per unit time). Therefore, the situation in which the liquid level of the coolant in the storage tank body changes due to the coolant flowing into the storage tank body will be suppressed. Therefore, the situation in which the air in the upper layer of the storage tank body is drawn into the coolant and then mixed into the coolant will be suppressed. As a result, the amount of air flowing out of the coolant circulation loop can be greatly reduced, thereby suppressing the deterioration of the cooling efficiency.

[0011] More specifically, the flow path shape inside the inflow portion may be a tapered shape having a predetermined angle in which the flow path area gradually increases from the other end side toward the one end side.

[0012] According to this, it is possible to suppress a rapid change in the flow rate of the coolant flowing inside the inflow portion. Moreover, by appropriately defining the predetermined angle of the tapered shape, it is possible to suppress the peeling of the coolant on the inner surface of the inflow portion. As a result, it is possible to reduce the flow rate of the coolant flowing inside the inflow portion (since the generation of a dead water area caused by the peeling of the coolant can be suppressed, the flow rate of the coolant can be reduced). Therefore, as described above, by suppressing the mixing of air into the coolant in the storage tank body, it is possible to suppress the deterioration of the cooling efficiency.

[0013] Furthermore, a guide vane for dividing a flow path of the coolant flowing inside the inflow portion into a plurality of parts may be provided inside the inflow portion.

[0014] Accordingly, the direction of the streamline of the coolant can be changed by the inner surface (e.g., conical surface) of the inflow portion or the surface of the guide vane. Therefore, the inclination angle of the flow channel shape can be increased while reducing the angle between the direction of the streamline of the coolant and the inner surface of the inflow portion or the surface of the guide vane. The inclination angle is the magnification of the cross-sectional area inside the inflow portion. Therefore, while suppressing the peeling of the coolant, the length of the inflow portion required to reduce the flow rate of the coolant flowing into the storage tank body to a predetermined flow rate can be shortened. The predetermined flow rate is a flow rate that can suppress the mixing of air into the coolant in the storage tank body. Therefore, the miniaturization of the inflow portion can be achieved while suppressing the mixing of air into the coolant in the storage tank body.

[0015] Furthermore, a pressure loss member that applies pressure loss to the coolant flowing inside the inflow portion may be provided inside the inflow portion.

[0016] In this case, by applying a pressure loss to the coolant flowing inside the inflow portion, the flow rate of the coolant can be reduced. Therefore, the peeling of the coolant on the inner surface of the inflow portion can be suppressed, and the inclination angle of the flow channel shape can be increased. Therefore, while suppressing the peeling of the coolant, the length of the inflow portion required to reduce the flow rate of the coolant flowing into the storage tank body to a predetermined flow rate can be shortened. Thus, while suppressing the mixing of air into the coolant in the storage tank body, the inflow portion can be miniaturized.

[0017] Furthermore, one end side of the inflow portion may be opened in a direction intersecting the side wall of the tank body, and the other end side of the inflow portion may be opened in a direction along the extension direction of the side wall of the tank body.

[0018] According to this, the coolant flowing into the inflow portion from the other end side will flow in the direction along the extension direction of the side wall of the storage tank body while reducing the flow velocity. In other words, compared with a structure in which the flow velocity is reduced while flowing in a direction intersecting the side wall of the storage tank body, the length of the inflow portion in the direction intersecting the side wall of the storage tank body can be shortened. Thus, the inflow portion can be miniaturized while suppressing the mixing of air in the storage tank body into the coolant.

[0019] In the present invention, in the inflow portion of the storage tank, the flow channel area of ​​one end side, which is the side closer to the storage tank body, is increased compared to the flow channel area of ​​the other end side, which is the side farther from the storage tank body. Therefore, it is possible to suppress the flow rate of the coolant while also reducing the flow rate in the inflow portion. Therefore, it is possible to suppress the air in the upper layer portion of the storage tank body from being drawn into the coolant and mixing the air into the coolant. As a result, the amount of air flowing out into the coolant circulation circuit can be greatly reduced, thereby suppressing the deterioration of the cooling efficiency. BRIEF DESCRIPTION OF THE DRAWINGS

[0020] Features, advantages, and technical and industrial significance of exemplary embodiments of the present invention will be described below with reference to the accompanying drawings, in which like symbols represent like elements, and in which:

[0021] Figure 1 It is a diagram showing a schematic structure of a coolant circulation circuit provided with a storage tank according to an embodiment.

[0022] Figure 2 It is a cross-sectional view of the periphery of the storage tank involved in the embodiment.

[0023] Figure 3 This is a cross-sectional view showing an enlarged inflow portion of the storage tank according to the embodiment.

[0024] Figure 4A It is a diagram showing an inflow portion of a storage tank according to a first modification, and is a cross-sectional view showing the inflow portion in an enlarged manner.

[0025] Figure 4B 1 is a diagram showing an inflow portion of a storage tank according to a first modification example, and is a cross-sectional view in a direction orthogonal to a streamline when a flow velocity reducing portion of the inflow portion is formed in a truncated cone shape.

[0026] Figure 4C1 is a diagram showing an inflow portion of a storage tank according to a first modification example, and is a cross-sectional view in a direction orthogonal to a flow line when a flow velocity reducing portion of the inflow portion is formed in a quadrangular pyramid shape.

[0027] Figure 5A It is a side view showing an inflow portion of a storage tank according to a second modification.

[0028] Figure 5B It is a perspective view showing an inflow portion of a storage tank according to a third modified example.

[0029] Figure 5C It is a perspective view showing an inflow portion of a storage tank according to a fourth modified example.

[0030] Figure 6 This is a cross-sectional view of the vicinity of the reservoir tank for explaining a situation in which air is mixed into the coolant in the reservoir tank in the prior art. DETAILED DESCRIPTION

[0031] Hereinafter, an embodiment of the present invention will be described based on the accompanying drawings. This embodiment describes a case where the present invention is applied to a structure of an inflow portion of a storage tank in a coolant circulation circuit provided in a battery cooling system of a battery electric vehicle. In addition, the coolant circulation circuit to which the present invention can be applied is not limited to the coolant circulation circuit in the battery cooling system of a battery electric vehicle. Examples of coolant circulation circuits to which the present invention can be applied include coolant circulation circuits in various cooling systems such as a cooling system for an inverter, a cooling system for an electric motor, and an engine cooling system in an engine-mounted vehicle.

[0032] Coolant circulation circuit schematic

[0033] Figure 1 1 is a diagram showing a schematic structure of a cooling liquid circulation circuit 1 provided with a storage tank 5 according to the present embodiment. Figure 1 As shown, in the coolant circulation circuit 1, a pump 2, a heat exchanger 3, a battery as a cooling target device (for example, a coolant flow channel provided inside the battery) 4, and a storage tank 5 are connected together by a pipe 6 in a manner that enables the circulation of the coolant.

[0034] The pump 2 is configured as an electric pump, for example, and circulates the coolant in the coolant circulation circuit 1 by operating.

[0035] The heat exchanger 3 performs heat exchange between the coolant circulating in the coolant circulation circuit 1 and the outside air, and releases the heat of the coolant to the outside air, thereby cooling the coolant. In addition, the medium for heat exchange with the coolant is not limited to the outside air.

[0036] The battery 4 stores electric power for feeding the driving motor or other electrical equipment as the driving force source of the battery electric vehicle. The battery 4 generates heat during charging and discharging. In recent battery electric vehicles, the energy density of the battery 4 is on the rise in order to improve the driving performance of the vehicle or extend the driving range. Therefore, effective cooling of the battery 4 is required. Therefore, it is required to reduce the amount of air in the coolant circulation circuit 1 to suppress the deterioration of the cooling efficiency.

[0037] The storage tank 5 includes a storage tank body 51 formed of a substantially cylindrical container for storing the coolant. The storage tank body 51 is connected to the pipe (the pipe extending from the battery 4) 6 via the inflow portion 52. The storage tank body 51 is connected to the pipe (the pipe extending to the suction side of the pump 2) 6 via the outflow portion 53. In addition, the storage tank 5 has a function of absorbing the volume change caused by the thermal expansion of the coolant. In addition, the storage tank 5 is used to replenish the coolant to the coolant circulation circuit 1.

[0038] Storage tank structure

[0039] Next, the structure of the storage tank 5 will be described. Figure 2 4 is a cross-sectional view of the storage tank 5 and its surroundings according to the present embodiment. Figure 2 As shown in FIG. 1 , the storage tank 5 is configured to include a storage tank body 51 , and an inflow portion 52 and an outflow portion 53 that are integrally connected to the storage tank body 51 .

[0040] The storage tank body 51 is composed of a substantially cylindrical container and includes a side wall 51a, a top plate 51b, and a bottom plate 51c. A predetermined amount of coolant 7 is stored inside the storage tank body 51. When the coolant 7 stored inside the storage tank body 51 is reduced to a predetermined amount (when the liquid level of the coolant 7 drops to a predetermined position), the coolant 7 is replenished from the top plate 51b side of the storage tank body 51. Since the structure for replenishment is a well-known structure, it is omitted from the illustration. In addition, the storage tank body 51 is not limited to a substantially cylindrical container, and can also be composed of a square cylindrical container.

[0041] In one side wall (at the Figure 2The inflow portion 52 is integrally connected to the lower portion of the side wall 51a (the side wall on the left side in the figure). In addition, the outflow portion 53 is integrally connected to the bottom plate 51c of the storage tank body 51 at a position close to the side wall 51a' on the opposite side to the side wall 51a to which the inflow portion 52 is connected. The side wall on the opposite side to the side wall 51a is the side wall opposite to the side wall 51a (in the figure). Figure 2 The side wall located on the right side in the middle) 51a'.

[0042] Inflow section structure

[0043] Next, the structure of the inflow portion 52 which is a feature of this embodiment will be described. Figure 3 This is a cross-sectional view showing the inflow portion 52 in an enlarged manner. Figure 3 As shown, the inflow portion 52 includes a straight pipe portion 52a and a flow rate reducing portion 52b. The straight pipe portion 52a is a portion connected to the pipe 6 of the coolant circulation circuit 1, and the flow rate reducing portion 52b is a portion connected to the side wall 51a of the storage tank body 51.

[0044] The straight pipe portion 52a is formed by a straight pipe having a uniform inner diameter over the entire length direction. The outer diameter of the straight pipe portion 52a is substantially consistent with the inner diameter of the pipe 6. Figure 2 As shown, the pipe 6 and the inflow portion 52 are connected by inserting the straight pipe portion 52a into the pipe 6. Conversely, the pipe 6 and the inflow portion 52 may be connected by inserting the pipe 6 into the straight pipe portion 52a. In the present embodiment, the inner diameter and outer diameter of the straight pipe portion 52a are substantially the same as the inner diameter and outer diameter of the outflow portion 53 formed by the straight pipe.

[0045] The side of the flow velocity reducing portion 52b that is closer to the storage tank body 51 (the side connected to the storage tank body 51) is set as one end side of the flow velocity reducing portion 52b. The side of the flow velocity reducing portion 52b that is farther from the storage tank body 51 (the side connected to the straight pipe portion 52a) is set as the other end side of the flow velocity reducing portion 52b. In this case, the flow channel area of ​​the one end side of the flow velocity reducing portion 52b is larger than the flow channel area of ​​the other end side. More specifically, the flow channel shape inside the flow velocity reducing portion 52b is a tapered shape in which the flow channel area gradually increases as it approaches from the other end side to the one end side.

[0046] Thus, the flow passage area at one end of the flow velocity reduction portion 52b is larger than the flow passage area at the other end. As a result, the cooling liquid ( Figure 3 The cooling liquid 7 with a flow rate V1 in the inflow portion 52 is prevented from decreasing the flow rate and the flow rate of the cooling liquid 7 is also reduced. Figure 3 The flow rate in the inflow portion 52 is the amount of the coolant 7 flowing into the storage tank body 51 per unit time.

[0047] As the flow channel shape inside the flow velocity reducing portion 52b, more specifically, the inclination angle (opening angle) θ of the tapered shape is set to be less than 5°. This is because, since there is a possibility of peeling of the coolant 7 on the inner surface of the inflow portion 52 when the inclination angle θ of the tapered shape is too large, such peeling is suppressed. In other words, in the case where the coolant 7 peels off on the inner surface of the inflow portion 52, a dead water area is generated, and there is a possibility that the flow velocity of the coolant 7 cannot be reduced. In view of this, the inclination angle of the tapered shape is specified as described above, so that the peeling of the coolant 7 on the inner surface of the inflow portion 52 is suppressed, and by suppressing the generation of the dead water area, the flow velocity of the coolant 7 can be reduced.

[0048] The flow velocity reduction portion 52b is configured as follows. Therefore, in order to reduce the flow velocity of the coolant 7 to a predetermined flow velocity while setting the inclination angle θ of the tapered shape to the inclination angle described above, it is necessary to extend the length dimension of the flow velocity reduction portion 52b as the ratio C=A2 / A1 increases. A1 is the cross-sectional area of ​​the other end side of the flow velocity reduction portion 52b (the end on the upstream side of the flow direction of the coolant 7). A2 is the cross-sectional area of ​​one end side of the flow velocity reduction portion 52b (the end on the downstream side of the flow direction of the coolant 7).

[0049] Coolant inflow status

[0050] Next, the flow state of the coolant 7 into the reservoir tank body 51 achieved by the inflow portion 52 having the above-described configuration will be described. Figure 2 The dashed arrows in refracted FIG. 5 represent the respective flows of the coolant 7 flowing into the lower reservoir tank body 51 and the coolant 7 flowing out from the reservoir tank body 51 to the coolant circulation circuit 1 .

[0051] The coolant 7 flowing into the inflow portion 52 from the pipe 6 of the coolant circulation circuit 1 flows through the flow velocity reduction portion 52b after passing through the straight pipe portion 52a. The flow channel shape inside the flow velocity reduction portion 52b is a tapered shape in which the flow channel area gradually increases as it tends toward the flow direction of the coolant 7. Therefore, while suppressing the decrease in the flow rate of the coolant 7 in the inflow portion 52 (the amount of the coolant 7 flowing into the storage tank body 51 per unit time), the flow velocity of the coolant 7 is also reduced. Therefore, the flow velocity of the coolant 7 flowing into the storage tank body 51 is also reduced.

[0052] In the prior art, the coolant (coolant with a relatively high flow rate) flowing into the storage tank body collides with the side wall of the storage tank body (the side wall opposite to the side wall provided with the inflow portion), and the streamline is turned upward. As a result, the coolant level fluctuates, and the air in the upper layer of the storage tank body is likely to be drawn into the coolant. Therefore, the air flows out from the outflow portion into the coolant circulation circuit, resulting in a deterioration in cooling efficiency.

[0053] In contrast, in the present embodiment, since the flow rate of the coolant 7 flowing into the storage tank body 51 is reduced, the liquid level of the coolant 7 is suppressed from changing. As a result, it is possible to suppress the air A in the upper layer portion of the storage tank body 51 from being drawn into the coolant 7. Therefore, the amount of air flowing out into the coolant circulation circuit 1 can be greatly reduced, thereby suppressing the deterioration of the cooling efficiency.

[0054] Effects of implementation methods

[0055] As described above, in the present embodiment, the flow passage area of ​​one end side, which is the side closer to the tank body 51, is increased compared to the flow passage area of ​​the other end side, which is the side farther from the tank body 51, in the inflow portion 52 of the tank 5. Therefore, it is possible to suppress the decrease in the flow rate in the inflow portion 52 and also to reduce the flow rate of the coolant 7. As a result, it is possible to suppress the air A in the upper layer portion of the tank body 51 from being drawn into the coolant 7 and mixing the air into the coolant 7. As a result, it is possible to significantly reduce the amount of air flowing out of the coolant circulation circuit 1, thereby suppressing the deterioration of the cooling efficiency. Moreover, since it is possible to suppress the deterioration of the cooling efficiency in this way, it is possible to achieve effective cooling of the battery 4, thereby contributing to the improvement of the energy consumption rate (power consumption rate).

[0056] In addition, the inventors of the present invention calculated the amount of air flowing out of the outflow portion 53 (the amount of air flowing out to the coolant circulation circuit 1) by numerical analysis. Specifically, as in the prior art, the ratio of the cross-sectional area of ​​the downstream end of the inflow portion to the upstream end was set to 1, while in the present invention, the ratio of the cross-sectional area of ​​the downstream end of the inflow portion 52 to the upstream end was set to 2. As a result, it was confirmed that the amount of air flowing out of the outflow portion 53 was reduced by about 50% in the storage tank 5 according to the present invention compared to the storage tank of the prior art. As a result, it was confirmed that the deterioration of the cooling efficiency could be suppressed.

[0057] First change example

[0058] Next, the first modification example is described. The structure of the flow velocity reduction portion 52b in this modification example, especially the structure inside the flow velocity reduction portion 52b, is different from the structure of the embodiment described above. Since the other structures are the same as those of the embodiment, only the differences from the embodiment are described here.

[0059] FIG. 4A to FIG. 4C It is a diagram showing an inflow portion 52A of the storage tank 5 according to the present modification. Figure 4A It is a cross-sectional view showing the inflow portion 52A in an enlarged manner. Figure 4B It is a cross-sectional view in a direction orthogonal to the streamline when the flow velocity reduction portion 52b of the inflow portion 52A is formed in a truncated cone shape.

[0060] As shown in these drawings, in the flow velocity reduction portion 52b according to the present modification, a plurality of guide vanes 52c, 52c, ... are provided to divide the flow path of the coolant 7 flowing therein into a plurality of portions. Figure 4B As shown, each guide vane 52c extends in the horizontal direction and is connected to the inner surface of the flow velocity reduction portion 52b at both ends. As a result, the interior of the flow velocity reduction portion 52b spans the vertical direction to form a plurality of independent flow channels. In addition, as the inclination angle (inclination angle relative to the horizontal direction) of each guide vane 52c, 52c, ..., the more the guide vane 52c is located on the outside (located on the outside in the vertical direction), the larger the inclination angle. More specifically, the inclination angle of each guide vane 52c, 52c, ... is configured so that the angle formed with the adjacent wall surface (the inner surface of the flow velocity reduction portion 52b or the wall surface of the adjacent guide vane 52c) is less than a predetermined angle (for example, 5°).

[0061] In this way, when the guide vanes 52c, 52c, ... are provided inside the flow velocity reduction portion 52b, the direction of the streamline of the coolant 7 can be changed (slightly changed to the outside) by the inner surface of the flow velocity reduction portion 52b or the surface of the guide vane 52c. The inner surface of the flow velocity reduction portion 52b is, for example, a conical surface. As a result, while the angle between the direction of the streamline of the coolant 7 and the inner surface of the flow velocity reduction portion 52b or the surface of the guide vane 52c is reduced, the inclination angle of the flow path shape can be increased. The inclination angle of the flow path shape is the magnification of the cross-sectional area inside the flow velocity reduction portion 52b. Therefore, while suppressing the peeling of the coolant 7, the length of the inflow portion 52A required to reduce the flow velocity of the coolant 7 flowing into the storage tank body 51 to a predetermined flow velocity can be shortened. The predetermined flow velocity is a flow velocity that can suppress the mixing of air into the coolant 7 in the storage tank body 51. Therefore, it is possible to reduce the size of the inflow portion 52A while suppressing the mixing of the air in the reservoir tank body 51 into the coolant 7 .

[0062] in addition, Figure 4C 2 is a cross-sectional view in a direction perpendicular to the streamline when the flow velocity reduction portion 52b of the inflow portion 52A is set to a quadrangular pyramid shape. Figure 4C In the structure shown, a plurality of guide vanes 52c, 52c, ... are provided inside the flow velocity reduction portion 52b. In this structure, as described above, while suppressing the separation of the coolant 7, it is also possible to shorten the length of the inflow portion 52A required to reduce the flow velocity of the coolant 7 flowing into the storage tank body 51 to a predetermined flow velocity. Therefore, it is possible to suppress the mixing of air in the storage tank body 51 into the coolant 7 and also to achieve miniaturization of the inflow portion 52A.

[0063] Second modification example

[0064] Next, the second modification example will be described. The structure of the flow velocity reduction portion 52b in this modification example is also different from the structure of the embodiment described above. Since the other structures are the same as those of the embodiment, only the differences from the embodiment will be described here.

[0065] Figure 5A 1 is a perspective view showing the inflow portion 52B of the storage tank 5 according to the present modification. Figure 5A As shown, the enlarged diameter portion 52d, the cylindrical portion 52e, and the reduced diameter portion 52f of the flow velocity reducing portion 52b of the inflow portion 52B according to the present modification are integrally arranged along the flow direction of the coolant 7.

[0066] The flow path shape inside the expanded diameter portion 52d is a tapered shape in which the flow path area gradually increases as it moves from the other end side to the one end side. Figure 5A The left side in the figure is an example of "the other end side which is farther from the storage tank body" in the present invention. The downstream side ( Figure 5A The right side in the figure) is an example of “an end side which is closer to the storage tank body” as referred to in the present invention.

[0067] In addition, a pressure loss component 52g (in the cylinder 52e) made of a mesh material or a porous body is accommodated inside. Figure 5AIndicated by dotted lines in the figure). The shape of the pressure loss component 52g is a cylindrical shape that is roughly consistent with the shape of the inside of the cylindrical portion 52e. Thus, when the coolant 7 passes through the inside of the cylindrical portion 52e, pressure loss will be applied to the coolant 7. Therefore, the coolant 7 flowing into the inflow portion 52B has a reduced flow rate in the expanded diameter portion 52d, and thus becomes difficult to peel off. Therefore, as the flow channel shape inside the expanded diameter portion 52d, the inclination angle can be increased, so that it is difficult to peel off even when the inclination angle is set to more than 5°. Therefore, while suppressing the peeling of the coolant 7, the length of the inflow portion 52B required to reduce the flow rate of the coolant 7 flowing into the storage tank body 51 to a predetermined flow rate can be shortened. Thus, while suppressing the mixing of air into the coolant 7 in the storage tank body 51, the miniaturization of the inflow portion 52B can be achieved.

[0068] The reason why the reduced diameter portion 52f is provided on the downstream side of the cylindrical portion 52e is to rectify the flow of the coolant 7 and allow it to flow into the reservoir tank body 51. This is because it is considered that when the coolant 7 flows through the cylindrical portion 52e, the velocity distribution of the coolant 7 may be disturbed due to passing through the pressure loss component 52g.

[0069] The third modification example

[0070] Next, a third modification example will be described. The overall structure of the inflow portion 52 in this modification example is different from that of the embodiment described above. Since the other structures are the same as those of the embodiment, only the differences from the embodiment will be described here.

[0071] Figure 5B 5 is a perspective view showing the inflow portion 52C of the storage tank 5 according to the present modification. Figure 5B As shown, the inflow portion 52C according to the present modification example is configured integrally with an upstream straight pipe portion 52h, a cylindrical portion 52i, and a downstream straight pipe portion 52j.

[0072] The upstream straight pipe portion 52h extends in the vertical direction (the extension direction of the side wall 51a of the storage tank body 51). The upstream end side of the upstream straight pipe portion 52h in the flow direction of the coolant 7 is opened downward, and the open portion is connected to the pipe 6.

[0073] The cylindrical portion 52i is formed into a cylindrical shape with the horizontal direction (the direction intersecting the side wall 51a of the storage tank body 51) as the direction of the center line. In addition, the upstream straight pipe portion 52h is connected to the cylindrical portion 52i from the lower side of the tangential direction of the outer peripheral surface of the cylindrical portion 52i. Therefore, when the coolant 7 flows into the cylindrical portion 52i from the upstream straight pipe portion 52h, the coolant 7 becomes a swirling flow along the inner peripheral surface of the cylindrical portion 52i and flows inside the cylindrical portion 52i. In addition, the flow rate of the coolant 7 is reduced by increasing the internal area of ​​the cylindrical portion 52i (the area in the direction orthogonal to the direction of the streamline of the swirling flow) compared to the flow channel area of ​​the upstream straight pipe portion 52h. Therefore, the portion of the cylindrical portion 52i to which the upstream straight pipe portion 52h is connected is an example of "the other end side as the side farther from the storage tank body" as mentioned in the present invention. The downstream side portion of the inner space of the cylindrical portion 52i in the flow direction of the coolant 7 is an example of "one end side which is closer to the reservoir tank body" as referred to in the present invention.

[0074] In addition, the downstream straight pipe portion 52j is connected to the center of the side wall of the cylindrical portion 52i that is opposite to the storage tank body 51. The opening direction of the downstream straight pipe portion 52j is a horizontal direction (a direction intersecting the side wall 51a of the storage tank body 51). The open portion is connected to the side wall 51a of the storage tank body 51. In addition, the inner diameter of the downstream straight pipe portion 52j is set larger than the inner diameter of the upstream straight pipe portion 52h, so that when the coolant 7 flows inside the downstream straight pipe portion 52j, the flow rate of the coolant 7 does not become too high.

[0075] In this modification, the coolant 7 flowing into the inflow portion 52C decreases in flow velocity while flowing in the direction along the extension direction of the side wall 51a of the reservoir tank body 51. That is, compared with the case where the flow velocity decreases while flowing in the direction intersecting the side wall 51a of the reservoir tank body 51, the length of the inflow portion 52C in the direction intersecting the side wall 51a of the reservoir tank body 51 can be shortened. Thus, it is possible to suppress the mixing of air in the reservoir tank body 51 into the coolant 7 and also to achieve miniaturization of the inflow portion 52C.

[0076] Fourth Modification

[0077] Next, the fourth modification will be described. The structure of the upstream straight pipe portion 52h in this modification is different from that of the third modification described above. Since the other structures are the same as those of the third modification, only the differences from the third modification will be described here.

[0078] Figure 5C 2 is a perspective view showing the inflow portion 52D of the storage tank 5 according to the present modification. Figure 5C As shown, the inflow portion 52D according to this modification also integrally configures the upstream straight pipe portion 52h, the cylindrical portion 52i, and the downstream straight pipe portion 52j. The structures of the cylindrical portion 52i and the downstream straight pipe portion 52j are the same as those of the third modification described above.

[0079] The upstream straight pipe portion 52h extends in the direction along the up-down direction (the extension direction of the side wall 51a of the storage tank body 51). In addition, the upstream end side of the upstream straight pipe portion 52h in the flow direction of the coolant 7 is opened upward, and the open portion is connected to the pipe 6. In addition, the upstream straight pipe portion 52h is connected to the cylindrical portion 52i from the upper side in the tangential direction of the outer peripheral surface of the cylindrical portion 52i.

[0080] In this modification, the coolant 7 flowing into the inflow portion 52D decreases in flow velocity while flowing in the direction along the extension direction of the side wall 51a of the reservoir tank body 51. That is, compared with the case where the flow velocity decreases while flowing in the direction intersecting the side wall 51a of the reservoir tank body 51, the length of the inflow portion 52D in the direction intersecting the side wall 51a of the reservoir tank body 51 can be shortened. Thus, it is possible to suppress the mixing of air in the reservoir tank body 51 into the coolant 7 and also to achieve miniaturization of the inflow portion 52D.

[0081] Furthermore, in the configurations of the third and fourth modified examples described above, since the opening direction of the upstream straight pipe portion 52h can be arbitrarily set, the degree of freedom in mounting the reservoir tank 5 on the vehicle can be increased.

[0082] Other Implementations

[0083] The present invention is not limited to the above-described embodiment and modifications, and all modifications and applications included in the scope of the claims and the scope equivalent to the scope are possible.

[0084] For example, in the above-described embodiment and the above-described modifications, the storage tank body 51, the inflow portion 52 (52A, 52B, 52C, 52D), and the outflow portion 53 may be integrally formed to constitute the storage tank 5. The present invention is not limited thereto. The storage tank body 51, the inflow portion 52 (52A, 52B, 52C, 52D), and the outflow portion 53 may be separately formed and integrally assembled to constitute the storage tank 5.

[0085] In addition, in the embodiment and the first modified example, the shape of the flow velocity reduction portion 52b is a conical shape. The conical shape is a conical shape in which the flow channel area gradually increases as it approaches from the other end side to the one end side across the entire periphery. The other end side is the side farther from the storage tank body 51 in the flow direction of the coolant 7. The one end side is the side closer to the storage tank body 51 in the flow direction of the coolant 7. The present invention is not limited to this, and it can also be a shape in which a part of the periphery of the flow velocity reduction portion 52b is inclined as it approaches from the other end side to the one end side so that the flow channel area gradually increases. For example, it can also be a shape in which only the upper part of the flow velocity reduction portion 52b expands upward. In addition, as the flow channel shape inside the inflow portion 52, as long as the flow channel area of ​​the one end side is larger than the flow channel area of ​​the other end side, it is not necessarily a conical shape. For example, the inner surface of the inflow portion 52 can also be set to a stepped shape so that the flow channel area of ​​the one end side is larger than the flow channel area of ​​the other end side.

[0086] The present invention can be applied to the structure of an inflow portion of a reservoir tank in a coolant circulation circuit provided in a battery cooling system of a battery electric vehicle.

Claims

1. A structure of an inflow portion of a storage tank, wherein the storage tank is disposed in a coolant circulation circuit, wherein the structure of the inflow portion of the storage tank is characterized in that: When the side closer to the storage tank body in the flow direction of the coolant in the inflow portion is set as one end side, and the side farther from the storage tank body is set as the other end side, the flow channel area of ​​the one end side in the inflow portion is larger than the flow channel area of ​​the other end side.

2. The structure of the inflow portion of the storage tank according to claim 1, characterized in that: The flow path shape inside the inflow portion is a tapered shape having a predetermined angle in which a flow path area gradually increases as it goes from the other end side toward the one end side.

3. The structure of the inflow portion of the storage tank according to claim 1 or 2, characterized in that: A guide vane is provided inside the inflow portion to divide a flow path of the coolant flowing inside the inflow portion into a plurality of parts.

4. The structure of the inflow portion of the storage tank according to claim 1 or 2, characterized in that: A pressure loss member for imparting pressure loss to the cooling liquid flowing in the inlet portion is provided inside the inlet portion.

5. The structure of the inflow portion of the storage tank according to claim 1 or 2, characterized in that: One end of the inflow portion is open in a direction intersecting the side wall of the tank body, and the other end of the inflow portion is open in a direction along an extension direction of the side wall of the tank body.

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