Liquid storage device

Abstract

To provide a liquid storage device capable of suppressing bubble generation with improved effectiveness.SOLUTION: A liquid storage device 10 comprises: a reservoir tank 12, which is mounted on a vehicle and stores cooling liquid 100; and a floating cover 30, which floats on a surface of the cooling liquid 100 in the reservoir tank 12 and covers at least a portion of the liquid surface. The reservoir tank 12 includes a barrel portion 14 that stores the cooling liquid 100 and a tank inlet 18 having a smaller diameter than the barrel portion 14. The floating cover 30 has elasticity sufficient to allow the same to change from a stored state, in which the same can pass through the tank inlet 18, to an expanded state, in which the same spreads along the surface of the liquid by elastic restoring force.SELECTED DRAWING: Figure 1

Description

Technical Field

[0001] This specification discloses a liquid storage device mounted on a vehicle for storing a liquid.

Background Art

[0002] Conventionally, many liquid storage devices mounted on vehicles for storing liquids have been proposed. For example, Patent Document 1 discloses a liquid cooling system for cooling an internal combustion engine, an electric element, an electronic substrate, etc. This liquid cooling system has a reservoir tank for storing a coolant. The reservoir tank of Patent Document 1 has a tank body, an inflow pipe for feeding the coolant into the tank body, a columnar member, and a guide member. Both the columnar member and the guide member are fixed inside the tank body. When the liquid fed into the tank body from the inflow pipe hits the columnar member and the guide member, the rippling of the coolant, and thus the generation of bubbles, is suppressed to some extent.

Prior Art Documents

Patent Documents

[0003]

Patent Document 1

Summary of the Invention

Problems to be Solved by the Invention

[0004] However, in the case of the technology of Patent Document 1, since both the columnar member and the guide member are fixed to the tank body, they cannot appropriately follow the change in the liquid level. Also, in the case of Patent Document 1, since the entire liquid surface is open, the rippling on the liquid surface cannot be sufficiently suppressed. And, due to the generation of many waves on the liquid surface, air is entrained in the liquid and bubbles are generated. That is, in the technology of Patent Document 1, the generation of bubbles cannot be sufficiently suppressed.

[0005] Therefore, this specification discloses a liquid storage device that can more effectively suppress the generation of bubbles.

Means for Solving the Problem

[0006] The liquid storage device disclosed in this specification is mounted on a vehicle and includes a reservoir tank for storing a liquid, and a floating cover that floats on the liquid level of the liquid in the reservoir tank and covers at least a part of the liquid level. The reservoir tank has a body portion for storing the liquid and a tank inlet having a smaller diameter than the body portion. The floating cover has elasticity such that it can change from a storage state in which it can pass through the tank inlet to a deployed state in which it spreads along the liquid level by an elastic restoring force. This is the feature.

[0007] By providing a floating cover that floats on the liquid level, generation of bubbles can be appropriately suppressed even when the liquid level changes.

[0008] In this case, the floating cover may have a float portion having a specific gravity smaller than that of the liquid.

[0009] With such a configuration, sinking of the floating cover into the liquid can be prevented, and bubbles can be more reliably suppressed.

[0010] Further, the floating cover may be umbrella-shaped, and the floating cover may include a covering sheet that covers at least a part of the liquid level, and a plurality of skeletons that are radially arranged and to which the covering sheet is fixed.

[0011] With such a configuration, the floating cover can be changed between a storage state and a deployed state with a simple configuration. Further, since the floating cover has a skeleton, unintentional bending of the floating cover is effectively suppressed.

[0012] Further, the reservoir tank is further provided on the first side wall of the body portion, has an inlet for guiding the liquid in a horizontal inflow direction, and the floating cover in the deployed state may be in a shape that contacts or is close to the second side wall facing the first side wall at a position directly facing the inlet in a plan view and in the inflow direction.

[0013] With such a configuration, the floating cover can cover the location where the liquid is likely to splash. And thereby, the generation of bubbles can be more effectively suppressed.

[0014] Also, in two horizontal directions intersecting each other, the dimensions of the floating cover may be substantially the same as or slightly smaller than the inner dimensions of the reservoir tank.

[0015] With such a configuration, the movement of the floating cover in the reservoir tank can be suppressed.

Advantages of the Invention

[0016] According to the liquid storage device disclosed in this specification, the generation of bubbles can be more effectively suppressed.

Brief Description of the Drawings

[0017]

Figure 1

Figure 2

Figure 3

Figure 4

Figure 5

Figure 6

Embodiments for Carrying Out the Invention

[0018] Hereinafter, the configuration of the liquid storage device 10 will be described with reference to the drawings. FIG. 1 is a schematic cross-sectional view of the liquid storage device 10. This liquid storage device 10 is mounted on a vehicle and stores a liquid. For example, the liquid storage device 10 is a device that stores a coolant 100 for cooling an in-vehicle battery. Such a liquid storage device 10 is provided to absorb the volume fluctuation of the coolant 100 accompanying temperature changes and to separate the coolant 100 into gas and liquid.

[0019] The liquid storage device 10 includes a reservoir tank 12 and a floating cover 30. The reservoir tank 12 is a container that stores the coolant 100. The reservoir tank 12 is, for example, a container made of resin or metal. In this specification, a container in which a small-diameter tank inlet 18 is disposed on a large-diameter body portion 14 will be described as an example. Note that a tapered shoulder portion 16 exists between the tank inlet 18 and the body portion 14.

[0020] As shown in FIG. 1, the inlet 20 protrudes horizontally outward from the side wall of the body portion 14. Hereinafter, the side wall on which the inlet 20 is disposed will be referred to as the "first side wall 24", and the protruding direction of the inlet 20 will be referred to as the "inflow direction". Also, the side wall facing the first side wall 24 in the inflow direction will be referred to as the "second side wall 26".

[0021] As described above, the inlet 20 protrudes outward in the inflow direction. In the process of passing through this inlet 20, a flow in the inflow direction occurs in the coolant 100. Therefore, even after the coolant 100 flows into the reservoir tank 12, it flows in the downstream side in the inflow direction, that is, in the direction approaching the second side wall 26. Arrow A in FIG. 1 indicates such a flow of the coolant 100. As shown in FIG. 1, a part of such coolant 100 further collides with the second side wall 26 and then advances upward along the second side wall 26.

[0022] On the bottom wall of the body portion 14, an outlet 22 is formed. The outlet 22 protrudes downward from the bottom wall and then extends horizontally. Both the inlet 20 and the outlet 22 communicate with a flow path such as a cooling circuit. The coolant 100 circulates through the cooling circuit via this reservoir tank 12. Here, during the period when the coolant 100 stays in the reservoir tank 12, the bubbles contained in the coolant 100 gather upward. As a result, the coolant 100 from which the bubbles have been removed is output from the outlet 22. And thereby, air locks and the like that make it difficult for the pressure of the pump to be transmitted to the coolant 100 due to bubbles are effectively prevented. Also, the volume of the reservoir tank 12 is sufficiently larger than the volume of the coolant 100 to be stored. By providing such a reservoir tank 12 in the circulation path of the coolant 100, the volume change of the coolant 100 caused by temperature changes is absorbed.

[0023] The floating cover 30 is a covering member that floats on the liquid surface of the coolant 100 and covers at least a part of the liquid surface. This floating cover 30 is deformable between a stored state and a deployed state. The deployed state is a state in which the floating cover 30 spreads along the liquid surface. FIG. 1 shows the floating cover 30 in the deployed state. On the other hand, the stored state is a state in which the floating cover 30 is small enough to pass through the small-diameter tank inlet 18 and is folded or compressed.

[0024] Normally, the floating cover 30 is pressed by a user's finger to be in the stored state. Also, when the user stops pressing, the floating cover 30 automatically changes to the deployed state by the elastic restoring force.

[0025] The shape and material of the floating cover 30 are not limited as long as it floats on the liquid surface and automatically restores from the stored state to the deployed state. Therefore, the floating cover 30 may be a sponge sheet or a rubber sheet having a certain thickness.

[0026] Further, the floating cover 30 may have one or more skeletons and a covering sheet. FIG. 2 is a view of such a floating cover 30 seen from above. Further, FIG. 3 is a cross-sectional view taken along line B-B of FIG. 2.

[0027] The floating cover 30 in FIG. 2 is substantially umbrella-shaped. More specifically, this floating cover 30 has a central joint 38, a plurality of skeletons 32 radially extending from the central joint 38, a covering sheet 34, and a float portion 36. One end of the skeleton 32 is connected to the central joint 38 by a hinge 40. Then, as the skeleton 32 swings around the hinge 40, the floating cover 30 changes between a stored state and a deployed state. Note that the materials of the central joint 38 and the skeleton 32 are not particularly limited, but in order to prevent rust, both may be made of resin or metal with a rust-preventive coating.

[0028] A float portion 36 described later is attached to the tip of each of the plurality of skeletons 32. The float portion 36 is a member that adjusts the buoyancy acting on the floating cover 30. In this example, the specific gravity of the float portion 36 is sufficiently smaller than the specific gravity of the coolant 100. Therefore, when the floating cover 30 in the stored state is inserted into the liquid, due to the buoyancy acting on the float portion 36, the skeleton 32 automatically opens and transitions to the deployed state. Note that in order to surely open the skeleton 32, a spring that biases the skeleton 32 in the opening direction may be provided. In this case, the float portion 36 may be omitted.

[0029] The covering sheet 34 is a sheet material that covers the entire plurality of skeletons 32 and is fixed to the skeletons 32. As shown in FIG. 2, the covering sheet 34 may be fixed to the lower side of the deployed skeleton 32 and the float portion 36. With such a configuration, a gap is less likely to occur between the covering sheet 34 and the liquid surface, and the wave formation described later can be effectively suppressed.

[0030] The covering sheet 34 is composed of, for example, a waterproof sheet that does not allow water to pass through, such as a polyester sheet or the like. The waterproof sheet may be a moisture-permeable waterproof sheet that does not allow water to pass through but allows vapor to pass through. Also, if the floating cover 30 can be kept in a floating state, the covering sheet 34 may be a sheet that allows water to pass through, such as cloth or the like. Further, the covering sheet 34 has flexibility enough to sufficiently follow the swinging of the frame 32. That is, when the plurality of frames 32 are closed, the covering sheet 34 forms large pleats like the fabric of a closed umbrella. Also, when the plurality of frames 32 are open, the covering sheet 34 spreads flatly so as not to wrinkle.

[0031] Next, the reason for providing such a floating cover 30 will be described. The coolant 100 stored in the reservoir tank 12 may be agitated due to vibrations of the vehicle, water flow, or the like. In particular, when the coolant 100 flows vigorously into the reservoir tank 12 from the inlet 20, a water flow as indicated by the arrow A in FIG. 1 is generated, and the coolant 100 may jump up from the liquid surface. Due to such agitation, air may be entrained in the liquid, and bubbles may be generated in the coolant 100.

[0032] When a large amount of bubbles are mixed into the coolant 100, the pressure of the pump cannot be properly transmitted to the coolant 100, leading to a decrease in cooling efficiency and an increase in power consumption. Therefore, many techniques for suppressing the agitation of the coolant 100 have been proposed conventionally. For example, it has been proposed to provide a predetermined guide member inside the reservoir tank 12 and strike the water flow against the guide member to change the flow direction of the water or dampen the momentum of the water, thereby suppressing the agitation.

[0033] Here, the liquid level of the coolant 100 stored in the reservoir tank 12 changes according to the situation. When the liquid level changes, the arrangement of the guide member suitable for suppressing bubbles also changes. However, conventionally, the guide member has been fixedly installed with respect to the reservoir tank 12. Therefore, the conventional guide member could not follow the change in the liquid level, and the generation of bubbles could not be sufficiently suppressed. Moreover, originally, in the prior art, since the entire liquid surface of the coolant 100 was open, the rippling on the liquid surface could not be sufficiently suppressed.

[0034] On the other hand, the technology disclosed in this specification includes a floating cover 30 that floats on the liquid surface. Since the floating cover 30 is configured to float on the liquid surface, it can always follow the change in the liquid level. As a result, according to the technology disclosed in this specification, the rippling on the liquid surface is suppressed, and the generation of bubbles is effectively suppressed. Further, the floating cover 30 covers a part of the liquid surface in a state of being in contact with the liquid surface. In other words, there is no or a small air layer between the covering sheet 34 and the liquid surface. Therefore, even if the coolant 100 tries to jump up from the liquid surface, the coolant 100 hits the covering sheet 34. As a result, the coolant 100 does not touch the air layer, and the flow direction of the coolant 100 changes. And thereby, the rippling, and thus the generation of bubbles, are effectively suppressed.

[0035] By the way, as repeatedly described, when the coolant 100 vigorously flows into the reservoir tank 12 from the inlet 20, a water flow as shown by the arrow A in FIG. 1 occurs. This water flow proceeds in the inflow direction from the inlet 20 and, when hitting the second side wall 26, goes upward. Therefore, when the water flow of arrow A occurs, in a plan view, at the position directly facing the inlet 20 in the inflow direction, that is, at portion C in FIGS. 1 and 2, the coolant 100 is likely to jump up.

[0036] In order to effectively suppress the splashing of the coolant 100 in this C part, the floating cover 30 may be shaped to contact or be close to the second side wall 26 in the C part. In the C part, by eliminating or reducing the gap between the floating cover 30 and the second side wall 26, the splashing of the coolant 100 in the C part is effectively suppressed.

[0037] Also, in two horizontal directions intersecting each other, the dimensions of the floating cover 30 are approximately the same as or slightly smaller than the inner dimensions of the reservoir tank 12. For example, in the case of FIG. 2, the dimension of the floating cover 30 in the left - right direction on the paper surface is slightly smaller than the dimension of the reservoir tank 12 in the left - right direction on the paper surface. Also, the dimension of the floating cover 30 in the up - down direction on the paper surface is slightly smaller than the inner dimension of the reservoir tank 12 in the up - down direction on the paper surface. Thereby, the horizontal movement of the floating cover 30 is effectively suppressed. And thereby, in the C part, the gap between the floating cover 30 and the second side wall 26 can be kept small, and the generation of bubbles can be effectively suppressed.

[0038] Also, as described above, in the example of FIG. 2, the floating cover 30 has a framework 32. Since the framework 32 has appropriate rigidity, it will not buckle and can maintain its shape even when receiving some water pressure. As a result, even if a strong water flow occurs in the reservoir tank 12, the shape of the floating cover 30 is maintained in a shape suitable for suppressing undulations. For example, by providing the framework 32, problems such as "the end of the floating cover 30 breaks under water pressure" do not occur. As a result, by providing the framework 32, the generation of bubbles can be more effectively suppressed.

[0039] The configurations described so far are all examples. As long as the configuration of claim 1 is provided, other configurations may be appropriately changed. For example, in the above description, the float portion 36 is provided at the end of the skeleton 32. However, if the floating cover 30 can appropriately transition to the deployed state and can float on the liquid surface, the float portion 36 may be omitted. In that case, the size and specific gravity of the skeleton 32 and the covering sheet 34 may be adjusted so that the floating cover 30 in the deployed state floats on the liquid surface.

[0040] Also, in the previous description, substantially the entire floating cover 30 is covered with the covering sheet 34. However, if the generation of bubbles can be suppressed, holes may be formed in the covering sheet 34. For example, as shown in FIG. 4, a central hole 42 may be formed substantially at the center of the covering sheet 34. Even in this case, since the portion where the coolant 100 is likely to splash, that is, part C, is covered with the covering sheet 34, the generation of bubbles can be effectively suppressed. Further, by providing the central hole 42, the bubbles floating on the liquid surface can be efficiently discharged into the upper space. In this case, as shown in FIG. 5, the floating cover 30 may be formed in a mortar shape that gradually becomes higher from the outer peripheral edge toward the center. With such a configuration, the bubbles 110 that have floated up to the covering sheet 34 are then further guided to the central hole 42. In this case, the specific gravity of the float portion 36 may be slightly larger than the specific gravity of the coolant 100 so that the tip of the skeleton 32 slightly sinks below the liquid surface.

[0041] In addition, in FIGS. 1 to 5, a simple shape, for example, a reservoir tank 12 having a square cross section is taken as an example. However, the technology disclosed in this specification may also be applied to a reservoir tank 12 having a more complex shape. For example, as shown in FIG. 6, the reservoir tank 12 may have a gourd-shaped cross section formed by connecting two circles. In this case, the floating cover 30 does not have to cover the entire liquid surface, and may cover only the portion where the splashing of the coolant 100 is expected. For example, in the case of the example in FIG. 6, splashing of the coolant 100 is predicted at the D portion facing the inlet 20. Therefore, as long as the floating cover 30 can cover the D portion, it does not have to cover the other portions.

Description of Reference Numerals

[0042] 10 Liquid storage device, 12 Reservoir tank, 14 Body portion, 16 Shoulder portion, 18 Tank inlet, 20 Inlet, 22 Outlet, 24 First side wall, 26 Second side wall, 30 Floating cover, 32 Skeleton, 34 Coating sheet, 36 Float portion, 38 Central joint, 40 Hinge, 42 Central hole, 100 Coolant.

Claims

1. A reservoir tank mounted on a vehicle for storing a liquid, a floating cover that floats on the liquid surface in the reservoir tank and covers at least a part of the liquid surface, and the reservoir tank includes a body portion for storing the liquid, a tank inlet having a smaller diameter than the body portion, and the floating cover has elasticity such that it can change from a storage state in which it can pass through the tank inlet to a deployed state in which it spreads along the liquid surface by elastic restoring force. A liquid storage device characterized by the above.

2. The liquid storage device according to Claim 1, wherein the floating cover has a float portion having a specific gravity smaller than that of the liquid.

3. The liquid storage device according to Claim 1, wherein the floating cover has an umbrella shape, and the floating cover includes a covering sheet that covers at least a part of the liquid surface, and a plurality of skeletons arranged radially and to which the covering sheet is fixed. A liquid storage device characterized by the above.

4. The liquid storage device according to Claim 1, wherein the reservoir tank further has an inlet provided on a first side wall of the body portion for guiding the liquid in a horizontal inflow direction, and the floating cover in the deployed state has a shape that contacts or is close to a second side wall facing the first side wall at a position directly facing the inlet and the inflow direction in plan view. A liquid storage device characterized by the above.

5. The liquid storage device according to any one of Claims 1 to 4, wherein in two horizontal directions intersecting each other, the dimensions of the floating cover are substantially the same as or slightly smaller than the inner dimensions of the reservoir tank.

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