Cooling system

Abstract

The invention provides a cooling system. In the present disclosure, the problem is solved by providing a cooling system having a circulation path through which a non-aqueous insulating cooling liquid is circulated, and a cooling liquid storage unit which is provided in the circulation path and stores the insulating cooling liquid, the specific gravity of the insulating cooling liquid being smaller than that of water, and the specific gravity of the insulating cooling liquid being smaller than that of water. The cooling liquid storage part has a moisture removal part in the interior thereof, and the moisture removal part is fixed to the cooling liquid storage part such that at least a part of the upper surface thereof is in direct contact with the insulating cooling liquid.

Description

Technical Field

[0001] The present disclosure relates to cooling systems. Background Art

[0002] In a cooling system that circulates a coolant to cool electrical components such as batteries, the coolant used is required to have high insulation properties. If water is mixed into the coolant, it is possible that the terminals of the electrical components will short-circuit due to the water, the components will corrode, and other undesirable conditions will occur. In order to prevent the increase in the conductivity of the coolant, for example, Japanese Patent Application Laid-Open No. 2022-158432 discloses a technology for providing a filter for removing water in the circulation path of a cooling system using a non-aqueous insulating coolant.

[0003] In addition, Japanese Patent Publication No. 2001-050624 discloses a cooling device, which is provided with a filter for removing moisture in a manner that blocks the coolant ejection portion of a coolant storage container provided in a circulation path of the coolant. Japanese Patent Publication No. 02-216855 discloses a liquid cooling device for electrical and electronic components, which is provided with a moisture capture material that can react with water to capture moisture in the refrigerant. Japanese Patent Publication No. 2022-097321 discloses a water remover in which a granular water-absorbing polymer is enclosed in a metal net with a mesh structure, and Japanese Patent Publication No. 2017-104817 discloses a method for removing water dispersed in an oil phase using a powder of a water-absorbing resin enclosed in a resin mesh bag. Summary of the invention

[0004] When the water removal unit is provided in a manner that blocks the circulation path of the coolant, the flow resistance increases, the flow rate of the coolant decreases, and the cooling performance decreases significantly, so it is necessary to increase the output of the pressure pump for ensuring the flow rate. In addition, since water often condenses in non-aqueous coolants such as oil and exists as large water droplets, when a water-absorbing resin is enclosed in the mesh, the water droplets may not pass through the mesh and may not reach the water-absorbing resin.

[0005] The present disclosure has been made in view of the above-mentioned actual situation, and a main object thereof is to provide a cooling system capable of maintaining high insulation properties of an insulating coolant while suppressing circulation energy loss.

[0006] [1] The cooling system comprises a circulation path for circulating a non-aqueous insulating coolant and a coolant storage portion provided in the circulation path and storing the insulating coolant, wherein the insulating coolant has a specific gravity smaller than that of water, and the coolant storage portion comprises a moisture removal portion therein, wherein the moisture removal portion is fixed to the coolant storage portion in such a manner that at least a portion of an upper surface thereof is in direct contact with the insulating coolant.

[0007] [2] In the cooling system described in [1], at least a portion of the moisture removal unit may be fixed to a bottom surface of the coolant storage unit.

[0008] [3] In the cooling system described in [1] or [2], the moisture removal unit contains porous zeolite or water-absorbing resin as a moisture absorber.

[0009] [4] In the cooling system described in [3], the water-absorbing resin may be at least one selected from the group consisting of partially neutralized crosslinked polyacrylic acid, neutralized starch-acrylic acid graft polymer, hydrolyzate of starch-acrylonitrile graft polymer, saponified vinyl acetate-acrylate copolymer, isobutylene-maleic anhydride copolymer, hydrolyzate of acrylonitrile copolymer or acrylamide copolymer or their crosslinked products, acrylate-acrylamide copolymer, polyvinyl alcohol crosslinked product, modified polyethylene oxide crosslinked product, acrylamide-2-methylpropane sulfonate copolymer, (meth)acryloyl alkane sulfonate copolymer, crosslinked carboxymethyl cellulose salt and crosslinked polymers of cationic monomers.

[0010] [5] In the cooling system described in [3] or [4], the water-absorbing resin may be a cross-linked product of a partially neutralized polyacrylic acid or a neutralized product of a starch-acrylic acid graft polymer.

[0011] The cooling system in the present disclosure has the effect of being able to maintain high insulation properties of the insulating coolant while suppressing circulation energy loss. BRIEF DESCRIPTION OF THE DRAWINGS

[0012] 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 reference numerals represent like elements.

[0013] Figure 1 This is a schematic configuration diagram showing an example of a cooling system in the present disclosure.

[0014] Figure 2 This is a schematic cross-sectional view showing an example of a cooling liquid storage portion in the present disclosure.

[0015] Figure 3A It is a schematic cross-sectional view showing an example of a cooling liquid storage portion in the present disclosure.

[0016] Figure 3B It is a schematic cross-sectional view showing another example of the cooling liquid storage portion in the present disclosure.

[0017] Figure 4 It is a schematic cross-sectional view showing another example of the cooling liquid storage portion in the present disclosure.

[0018] Figure 5It is a schematic cross-sectional view showing an example of a coolant storage unit in which a conventional moisture removal unit is arranged. DETAILED DESCRIPTION

[0019] Hereinafter, the cooling system in the present disclosure will be described in detail.

[0020] Figure 1 This is a schematic configuration diagram showing an example of a cooling system in the present disclosure. Figure 1 The illustrated cooling system 100 includes a circulation path 1 for circulating a non-aqueous insulating coolant and a coolant storage unit 2 provided in the circulation path 1 and storing the insulating coolant. The flow of the insulating coolant in the circulation path 1 can be formed by using a pump 10 or the like. The cooling system 100 of the present disclosure can be mounted on a vehicle, for example, and can be used to cool heat generating devices such as an inverter 11, an oil cooler 12, and a battery 13 provided in series in the circulation path 1. By providing a radiator 14 in the circulation path 1 to perform heat exchange with the outside air, the heat generating device can be cooled to cool the heated insulating coolant.

[0021] Figure 2 1 is a schematic cross-sectional view showing an example of a cooling liquid storage unit in the present disclosure. The moisture removal unit 4 is fixed to the cooling liquid storage unit 2 in such a manner that at least a portion of its upper surface is in direct contact with the insulating cooling liquid 3. The insulating cooling liquid 3 used in the present disclosure has a smaller specific gravity than water, so the water mixed into the insulating cooling liquid 3 sinks in the cooling liquid storage unit 2, condenses to form droplets 21, is absorbed by the moisture removal unit 4 (moisture absorber 5), and is removed from the insulating cooling liquid 3.

[0022] In the cooling system of the present disclosure, the moisture removal unit is fixed to the cooling liquid storage unit in such a manner that at least a portion of its upper surface is in direct contact with the insulating cooling liquid, thereby being able to efficiently remove moisture from the insulating cooling liquid without stagnating the flow of the insulating cooling liquid in the circulation path. Therefore, the insulating property of the insulating cooling liquid can be maintained at a high level while suppressing the circulation energy loss.

[0023] If a moisture removal unit is provided in the form of blocking the circulation path of the coolant, the inlet and outlet of the coolant storage unit so that all the coolant passes through the moisture removal unit, the flow path resistance becomes larger, the flow rate of the coolant decreases, and the cooling performance is greatly reduced. Therefore, it is necessary to increase the output of the pressure pump to ensure the flow rate. On the other hand, as described above, in the present disclosure, since an insulating coolant with a specific gravity smaller than that of water is used, the water mixed in the insulating coolant sinks in the coolant storage unit and gathers at the bottom of the coolant storage unit. Therefore, by arranging a moisture removal unit at the location where water droplets gather in the coolant storage unit to absorb the water, it is possible to remove water from the insulating coolant without increasing the output of the pressure pump.

[0024] In addition, in a non-aqueous coolant such as oil, if a moisture absorber is enclosed in a mesh bag or the like, sometimes large condensed water droplets cannot pass through the mesh and cannot reach the water-absorbing resin. On the other hand, in the present disclosure, the moisture removal unit is fixed to the coolant storage unit in such a manner that at least a portion of its upper surface is in direct contact with the insulating coolant, so that the moisture removal unit is not blocked by a structure such as a mesh bag interposed between the moisture absorber of the moisture removal unit and the insulating coolant, and can absorb water droplets smoothly and quickly.

[0025] The cooling system in the present disclosure includes a circulation path for circulating an insulating coolant and a coolant storage unit for storing the insulating coolant. Hereinafter, each structure of the cooling system in the present disclosure will be described.

[0026] 1. Insulation coolant

[0027] The insulating coolant used in the present disclosure is not particularly limited as long as it is a non-aqueous liquid with a specific gravity lower than that of water and has insulating properties. For example, mineral oil containing hydrocarbon compounds such as aromatic hydrocarbons, paraffin hydrocarbons, and cycloalkane hydrocarbons can be used.

[0028] 2. Cycle Path

[0029] The circulation path in the cooling system disclosed herein is a path for circulating the insulating coolant. The circulation path is not particularly limited as long as it has piping for circulating the insulating coolant between the object to be cooled and the coolant storage unit, and can use common piping similar to piping for circulating lubricating oil, etc.

[0030] 3. Coolant storage

[0031] The coolant storage unit is provided in the circulation path and stores the insulating coolant. The coolant storage unit may be made of any material, shape, or size as long as it can store the insulating coolant therein. For example, the coolant storage unit may be appropriately set according to the shape of a place where the coolant storage unit is arranged, such as a rectangular or cylindrical container made of resin or metal, and the amount of the insulating coolant stored therein.

[0032] The type of the coolant storage unit is not particularly limited, and for example, a container with a single opening such as a pressurized water storage tank of a radiator can be used (see Figure 3A ). Alternatively, you can also use Figure 3B In the case of a two-port container, one port may be open to the atmosphere like an atmosphere-opening water storage tank, and the insulating coolant may flow in / out from the other port, or a circulation-type water storage tank may be used in which the insulating coolant flows in from one port and is discharged from the other port.

[0033] A moisture removal unit is fixed inside the coolant storage unit. The location of the moisture removal unit in the coolant storage unit is not particularly limited as long as it does not hinder the flow of the insulating coolant, and it can be arranged on the bottom surface and side surface of the coolant storage unit in a manner that does not block the inlet and outlet of the insulating coolant. Among them, it is preferred that at least a portion of the moisture removal unit is arranged on the bottom surface of the coolant storage unit. This is because the water droplets that sink to the bottom surface of the coolant storage unit can be effectively absorbed by utilizing the specific gravity difference. At this time, the moisture removal unit can be arranged only on a portion of the bottom surface of the coolant storage unit, or it can be arranged on the entire surface of the above-mentioned bottom surface.

[0034] The fixing of the moisture removal unit to the cooling liquid storage unit can be performed by directly or indirectly fixing the moisture absorber of the moisture removal unit to the cooling liquid storage unit. For example, when the moisture absorber of the moisture removal unit is a granular or block-shaped substance with a size of 5 mm or more, Figure 2 As shown in the example, the water removal unit 4 consisting of only the water absorber 5 can be directly bonded and fixed to the bottom surface of the cooling liquid storage unit 2. When the size of the particles or blocks of the water absorber is small, the surface area is large, so high water absorption performance can be exerted. On the other hand, when the size of the particles or blocks of the water absorber is large, high adhesion can be exerted. Therefore, the size of the water absorber is preferably small enough to exert stable adhesion, and can be appropriately selected for use according to the characteristics required by the water removal unit.

[0035] In addition, when the moisture absorber is a powder or granular substance with a size less than 5 mm, Figure 4 As shown in the example, the moisture absorber 5 is dispersed in the resin sheet (resin embedding portion 6), and the resin embedding portion 6 containing the moisture absorber 5 is bonded and fixed to the bottom surface of the coolant storage portion 2, so that the moisture absorber 5 can be indirectly fixed to the coolant storage portion 2. When the moisture removal portion has a moisture absorber and a resin filling portion, the moisture absorber is arranged so that at least a part of the surface of the moisture absorber is exposed to the surface (upper surface) of the resin embedding portion. By arranging such a moisture removal portion so as to be immersed in the insulating coolant, the moisture absorber can be directly in contact with the insulating coolant.

[0036] As the above-mentioned moisture absorber, for example, porous zeolites such as molecular sieves and water-absorbing resins can be cited. As the water-absorbing resin, for example, crosslinked products of partially neutralized polyacrylic acid, neutralized products of starch-acrylic acid graft polymers, hydrolyzates of starch-acrylonitrile graft polymers, saponified products of vinyl acetate-acrylate copolymers, crosslinked products of isobutylene-maleic anhydride copolymers, hydrolyzates of acrylonitrile copolymers or acrylamide copolymers or crosslinked products thereof, crosslinked products of acrylate-acrylamide copolymers, crosslinked products of polyvinyl alcohol, crosslinked products of modified polyethylene oxide, crosslinked products of acrylamide-2-methylpropanesulfonate copolymers, crosslinked products of (meth)acryloyl alkanesulfonate copolymers, crosslinked polymers of crosslinked carboxymethyl cellulose salts and cationic monomers can be cited. Among them, crosslinked products of partially neutralized polyacrylic acid and neutralized products of starch-acrylic acid graft polymers can be preferably used.

[0037] The resin used in the above-mentioned resin filling part is not particularly limited as long as it is resistant to the insulating coolant. For example, thermosetting resins such as epoxy resin, multifunctional cyanate resin, multifunctional maleimide-cyanate resin, multifunctional maleimide resin, unsaturated polyester resin, and polyphenylene ether resin containing unsaturated groups can be used.

[0038] 4. Cooling system

[0039] The use of the cooling system of the present disclosure is not particularly limited, and can be used, for example, for cooling batteries, inverters, oil coolers, etc. of hybrid electric vehicles (HEV), plug-in hybrid electric vehicles (PHEV), battery electric vehicles (BEV), gasoline vehicles, diesel vehicles, etc. In addition, the cooling system of the present disclosure can also be used for cooling electrical-related components such as working equipment and information processing devices of mobile bodies other than vehicles (for example, railways, ships, and airplanes).

[0040] A pressure pump for generating a circulation flow of the insulating coolant and a heat exchanger such as a radiator for reducing the temperature of the insulating coolant after cooling the object to be cooled may be arranged in the cooling system. In addition, a sensor for measuring the temperature, conductivity, water content, etc. of the insulating coolant, a reporting unit for notifying the surroundings of the situation when the measured value exceeds a threshold value, a control unit for controlling these components, etc. may be arranged in the circulation path.

[0041] The present disclosure is not limited to the above-mentioned embodiments. The above-mentioned embodiments are illustrative, and any structure having substantially the same structure and achieving the same function and effect as the technical concept described in the claims of the present disclosure is included in the technical scope of the present disclosure.

[0042] Example 1

[0043] like Figure 2As shown in the example, the coolant storage part 2 has a moisture removal part 4 in which a water-absorbing resin as a moisture absorber 5 is bonded and fixed to the bottom surface of the coolant storage part 2. The coolant storage part 2 is filled with non-aqueous insulating coolant 3, water droplets 21 are added, and it is left to stand for a certain period of time.

[0044] Example 2

[0045] like Figure 4 As shown in the example, the moisture removal part 4 in which the water-absorbing resin serving as the moisture absorber 5 is exposed on the upper surface of the resin embedding part 6 is fixed to the bottom surface of the coolant storage part 2, the coolant storage part 2 is filled with non-aqueous insulating coolant 3, water droplets 21 are added, and it is left to stand for a certain period of time.

[0046] Comparative Example

[0047] like Figure 5 As shown in the example, the bottom surface of the coolant storage portion 2 has a moisture removal portion 25 in which a water-absorbing resin serving as a moisture absorber 23 is sealed in a mesh bag 24 with a mesh size of about 1 mm. The coolant storage portion 2 is filled with non-aqueous insulating coolant 3, water droplets 21 are added, and the coolant is left to stand for a certain period of time.

[0048] evaluate

[0049] In Examples 1 and 2, water droplets sink due to the difference in specific gravity and reach the upper surface of the moisture removal section, where they are absorbed by the moisture absorber, and the moisture in the insulating coolant is removed. On the other hand, in the comparative example, as in Examples 1 and 2, water droplets reach the upper surface of the moisture removal section, but the water droplets remain on the moisture removal section and are not absorbed by the moisture removal section, so the moisture in the insulating coolant cannot be removed. It is presumed that this is because the surface tension is stronger than the force that causes the water droplets to settle in the mesh bag due to their own weight, and the water droplets cannot pass through the mesh structure and cannot reach the surface of the moisture absorber in the mesh bag.

Claims

1. A cooling system comprising: A circulation path for circulating a non-aqueous insulating coolant; and A cooling liquid storage unit is provided in the circulation path and stores the insulating cooling liquid, wherein: The insulating coolant has a lower specific gravity than water. The cooling liquid storage unit has a moisture removal unit therein. The moisture removal portion is fixed to the cooling liquid storage portion such that at least a portion of an upper surface thereof is in direct contact with the insulating cooling liquid.

2. The cooling system according to claim 1, wherein: At least a portion of the moisture removal unit is fixed to a bottom surface of the cooling liquid storage unit.

3. The cooling system according to claim 1 or 2, wherein: The moisture removal unit contains porous zeolite or a water-absorbing resin as a moisture absorber.

4. The cooling system according to claim 3, wherein: The water-absorbing resin is at least one selected from the group consisting of a partially neutralized cross-linked product of polyacrylic acid, a neutralized product of starch-acrylic acid graft polymer, a hydrolyzate of starch-acrylonitrile graft polymer, a saponified product of vinyl acetate-acrylate copolymer, an isobutylene-maleic anhydride copolymer cross-linked product, a hydrolyzate of acrylonitrile copolymer or acrylamide copolymer or a cross-linked product thereof, an acrylate-acrylamide copolymer cross-linked product, a polyvinyl alcohol cross-linked product, a modified polyethylene oxide cross-linked product, an acrylamide-2-methylpropane sulfonate copolymer cross-linked product, a (meth)acryloyl alkane sulfonate copolymer cross-linked product, a cross-linked carboxymethyl cellulose salt and a cross-linked polymer of a cationic monomer.

5. The cooling system according to claim 4, wherein: The water-absorbing resin is a cross-linked product of partially neutralized polyacrylic acid or a neutralized product of starch-acrylic acid graft polymer.

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