Protective Structure

Abstract

This invention provides a technology for preventing foreign objects from entering a housing that contains a protected object. [Solution] The protective structure comprises a housing portion for housing an object to be protected, a through hole provided on the outer surface of the housing portion and penetrating between the inside and outside of the outer surface, and a rotating body disposed within the through hole and supported so as to be rotatable within the through hole.

Description

Technical Field

[0001] The technology disclosed in this specification relates to a protection structure for a protected object.

Background Art

[0002] For example, Patent Document 1 discloses a protection structure for protecting a protected object (such as a battery, etc.). The protection structure of Patent Document 1 includes a housing portion (such as a housing, etc.) for housing the protected object. A through-hole is formed in the outer surface of the housing portion. Through the through-hole, air can pass between the outside and the inside of the housing portion.

Prior Art Documents

Patent Documents

[0003]

Patent Document 1

Summary of the Invention

Problems to be Solved by the Invention

[0004] In the housing portion of Patent Document 1, air passes between the outside and the inside of the housing portion by forming a through-hole in the outer surface. However, there is a risk that foreign matter may enter the inside of the housing portion through the through-hole.

[0005] This specification discloses a technology for suppressing the intrusion of foreign matter into a housing portion that houses a protected object.

Means for Solving the Problems

[0006] In a first aspect of this technology, the protection structure includes a housing portion for housing a protected object, a through-hole provided on the outer surface of the housing portion and penetrating between the inside and the outside of the outer surface, and a rotating body disposed in the through-hole and rotatably supported in the through-hole.

[0007] In this configuration, when a foreign object attempts to enter the through-hole, it comes into contact with the rotating body inside the through-hole, causing the rotating body to rotate. This changes the direction in which the foreign object enters, making it more difficult for the foreign object to enter the through-hole.

[0008] In a second aspect of this technology, in the first aspect described above, the rotating body may be made of a material that increases the gap between the through hole and the rotating body when a predetermined threshold temperature is exceeded.

[0009] With this configuration, when the temperature exceeds a predetermined threshold temperature, the gap between the through-hole and the rotating body increases, making it easier for air to move between the inside and outside of the housing through the through-hole. Therefore, when the rotating body exceeds the predetermined threshold temperature, the inside of the housing can be maintained at an appropriate temperature.

[0010] In a third aspect of this technology, in the first aspect described above, the rotating body may be made of a material that reduces the gap between the through hole and the rotating body when a predetermined threshold temperature is exceeded.

[0011] With this configuration, when a predetermined threshold temperature is exceeded, the gap between the through-hole and the rotating body becomes smaller, making it difficult for material to move between the inside and outside of the containment through the through-hole. Therefore, when a situation occurs in which the rotating body exceeds a predetermined threshold temperature, it is possible to suppress the release of material (for example, gas generated inside the containment due to the high temperature inside the containment) from the inside to the outside.

[0012] In a fourth aspect of this technology, in any one of the first to third aspects described above, the rotating body may be spherical.

[0013] With this configuration, the rotating body can rotate in various directions within the through hole.

[0014] In a fifth aspect of this technology, in any one of the first to fourth aspects described above, the protective structure may further include a rotating shaft that penetrates the center of the rotating body and extends along the outer surface. The rotating body may rotate around the rotating shaft.

[0015] In this configuration, the rotating body rotates around the axis of rotation, thus stabilizing its rotation. This allows for a consistent gap to be maintained between the through-hole and the rotating body.

[0016] In a sixth aspect of this technology, in the fifth aspect described above, the rotating body may have a linear hole passing through the center. The rotating shaft may be positioned in the hole.

[0017] This configuration allows the rotating body and the rotating shaft to be formed as separate components. As a result, when foreign matter comes into contact with the rotating body inside the through hole, the rotating shaft is less likely to rotate, while only the rotating body rotates easily. Therefore, when the rotating body rotates, friction is less likely to occur between the rotating shaft and the through hole, and the rotating shaft is less likely to come out of the through hole.

[0018] In a seventh aspect of this technology, the rotating body and the rotating shaft may be formed integrally with each other, as in the fifth aspect described above.

[0019] In this configuration, the rotating body rotates integrally with the axis of rotation. This allows the rotating body to rotate stably around the axis of rotation. Therefore, when foreign matter comes into contact with the rotating body inside the through hole and the rotating body rotates, the rotating body is less likely to come into contact with the through hole, and the rotation of the rotating body is less likely to be inhibited.

[0020] In the eighth aspect of this technology, in any one of the fourth to seventh aspects described above, the rotating body may have grooves formed on its surface.

[0021] According to this configuration, a gap is formed between the through-hole and the groove, so that air can easily pass through the through-hole. In addition, since the contact area between the through-hole and the rotating body is reduced, the friction when the rotating body rotates is reduced, and it becomes difficult to suppress the rotation of the rotating body.

Brief Description of the Drawings

[0022] [Figure 1] A diagram showing a schematic configuration of the protection structure according to Embodiments 1 and 2. [Figure 2] A diagram showing a rotating body, where (a) shows the rotating body of Embodiments 1 and 2, and (b) shows the rotating body of a modified example of Embodiments 1 and 2. [Figure 3] A diagram showing a schematic configuration of the protection structure according to Embodiment 3. [Figure 4] A diagram showing a rotating body, where (a) shows the rotating body of Embodiment 3, and (b) shows the rotating body of a modified example of Embodiment 3. [Figure 5] A diagram showing a schematic configuration of the protection structure according to Embodiment 4.

Modes for Carrying Out the Invention

[0023] (Embodiment 1) The protection structure 10 of this embodiment will be described with reference to the drawings. The protection structure 10 is a structure for protecting a protected body housed in a housing portion. As shown in FIG. 1, in this embodiment, the protected body is the battery cell 50, and the housing portion is the housing 12 that houses the battery cell 50. The housing 12 is a battery pack that houses a plurality of battery cells 50. In this embodiment, the housing 12 is in the shape of a rectangular parallelepiped box and is formed of aluminum. Note that the material of the housing 12 is not particularly limited. Also, the housing 12 may be a battery pack that houses only one battery cell 50.

[0024] Multiple through-holes 14 are formed on two opposing sides of the housing 12. Multiple through-holes 14 are formed on each side, and in this embodiment, three through-holes 14 are formed on each side. Each through-hole 14 extends in a direction perpendicular to the side and penetrates the side. The inside and outside of the housing 12 are in communication through each through-hole 14. By forming through-holes 14 on the sides, air can easily circulate between the inside and outside of the housing 12. This helps to suppress heat buildup inside the housing 12. The number of through-holes 14 formed on each side is not particularly limited. Also, the through-holes 14 may be formed on any side of the housing 12. The through-holes 14 only need to be formed on one or more of the six sides of the rectangular parallelepiped.

[0025] A rotating body 20 is positioned within each through-hole 14. The rotating body 20 is approximately spherical (see Figure 2(a)) and is rotatably supported within the through-hole 14. The through-hole 14 is slightly larger than the outer shape of the rotating body 20 and has a shape that conforms to the outer shape of the rotating body 20. As a result, a gap is formed between the through-hole 14 and the rotating body 20, and the through-hole 14 rotatably supports the rotating body 20. Because the rotating body 20 is spherical, it can rotate in various directions within the through-hole 14.

[0026] By placing the rotating body 20 inside the through-hole 14, it is possible to prevent foreign matter 52 from passing through the through-hole 14 and entering the housing 12. For example, if a foreign object 52 of a size that can pass through the through-hole 14 (e.g., a nail) 52 attempts to enter the through-hole 14, the foreign object 52 will come into contact with the rotating body 20. Since the rotating body 20 is rotatably supported inside the through-hole 14, it rotates inside the through-hole 14 upon contact with the foreign object 52. As the rotating body 20 rotates inside the through-hole 14, the direction of entry of the foreign object 52 is changed, making it more difficult for the foreign object 52 to enter the through-hole 14. Therefore, it becomes more difficult for foreign matter 52 to pass through the through-hole 14 and enter the housing 12. Furthermore, as described above, a gap is formed between the through-hole 14 and the rotating body 20, allowing air to circulate between the inside and outside of the housing 12 through the through-hole 14. Therefore, by placing the rotating body 20 inside the through-hole 14, it is possible to ensure ventilation while suppressing the entry of foreign matter 52 into the housing 12.

[0027] Furthermore, the rotating body 20 is made of a material that increases the gap between the through hole 14 and the rotating body 20 when a predetermined threshold temperature is exceeded. In this embodiment, the rotating body 20 is made of a material with a lower coefficient of thermal expansion than the housing 12, and the gap between the through hole 14 and the rotating body 20 increases when the temperature rises above the predetermined temperature. Specifically, the rotating body 20 is made of copper, and the coefficient of thermal expansion of copper is 17.7 × 10⁻⁶. -6 The temperature is °C. Also, as mentioned above, the housing 12 is made of aluminum, and the thermal expansion coefficient of aluminum is 23.9 × 10⁻⁶. -6 The temperature is °C. Note that the rotating body 20 only needs to be made of a material with a lower coefficient of thermal expansion than the housing 12, and the material of the rotating body 20 is not limited to copper. For example, the rotating body 20 could be made of chromium steel (coefficient of thermal expansion 11.3 × 10°C). -6 (°C) or alumina (coefficient of thermal expansion 7.2 × 10⁻⁶) -6It may be formed in °C. For example, when the temperature inside the housing 12 rises to 150 °C, the housing 12, which has a high coefficient of thermal expansion, expands more than the rotating body 20, which has a low coefficient of thermal expansion. That is, as the entire housing 12 expands, the size of the through hole 14 increases, while the rotating body 20 does not expand much, so the size of the rotating body 20 hardly changes. As a result, the gap between the through hole 14 and the rotating body 20 increases. This allows more air to circulate inside the housing 12, and the inside of the housing 12 can be cooled.

[0028] In this embodiment, the rotating body 20 was made of a material with a lower coefficient of thermal expansion than the housing 12 so that the gap between the through hole 14 and the rotating body 20 would increase when the temperature rose above a predetermined level. However, the embodiment is not limited to this configuration. For example, the rotating body 20 may be made of a material that softens when the temperature rises above a predetermined level. Specifically, the rotating body 20 may be made of low-density polyethylene with a melting point of 100 to 115°C. The melting point of the aluminum that forms the housing 12 is 660°C. Therefore, when the temperature inside the housing 12 rises to 150°C, the housing 12, with its high melting point, does not change shape, while the rotating body 20, with its low melting point, softens and changes shape. As a result, the rotating body 20 is no longer spherical, and the gap between the through hole 14 and the rotating body 20 increases. This allows more air to circulate inside the housing 12, thus cooling the inside of the housing 12.

[0029] Furthermore, in this embodiment, the rotating body 20 was made of a material that increases the gap between the through hole 14 and the rotating body 20 when the temperature rises above a predetermined level, but the configuration is not limited to this. For example, the rotating body 20 may be made of a material that increases the gap between the through hole 14 and the rotating body 20 when the temperature falls below a predetermined level. In this case as well, when the temperature falls below a predetermined level, air can circulate more easily inside and outside the housing 12, and the decrease in temperature inside the housing 12 can be suppressed.

[0030] (Example 2) In the above-described embodiment 1, the rotating body 20 was made of a material that increased the gap between the through hole 14 and the rotating body 20 when a predetermined threshold temperature was exceeded, but the configuration is not limited to this. For example, the rotating body 20 may be made of a material that decreased the gap between the through hole 14 and the rotating body 20 when a predetermined threshold temperature was exceeded. In this embodiment, the rotating body 20 is made of a material with a higher coefficient of thermal expansion than the housing 12, and the gap between the through hole 14 and the rotating body 20 increases when the temperature rises above a predetermined level. Specifically, in this embodiment, the housing 12 is made of silicon nitride, and the coefficient of thermal expansion of silicon nitride is 2.8 × 10⁻⁶. -6 The temperature is °C. The rotating body 20 is made of polytetrafluoroethylene, and the coefficient of thermal expansion of polytetrafluoroethylene is 10.0 × 10⁻⁶. -5 The temperature is °C. The rotating body 20 only needs to be made of a material with a greater coefficient of thermal expansion than the housing 12; the material of the rotating body 20 is not limited.

[0031] For example, when the temperature inside the housing 12 rises to 150°C, the rotating body 20, which has a high coefficient of thermal expansion, expands more than the housing 12, which has a low coefficient of thermal expansion. As a result, the gap between the through hole 14 and the rotating body 20 becomes smaller. Alternatively, the gap between the through hole 14 and the rotating body 20 is sealed. When the temperature inside the housing 12 becomes high, gas may be generated from the protected object (in this embodiment, the battery cell) 50 inside the housing 12. By forming the rotating body 20 from a material that reduces the gap between the through hole 14 and the rotating body 20 when the temperature rises above a predetermined temperature, it is possible to suppress the release of gas generated inside the housing 12 to the outside of the housing 12.

[0032] In this embodiment, the rotating body 20 was made of a material that reduces the gap between the through hole 14 and the rotating body 20 when the temperature rises above a predetermined level, but the configuration is not limited to this. For example, the rotating body 20 may be made of a material that reduces the gap between the through hole 14 and the rotating body 20 when the temperature falls below a predetermined level. In this case as well, when the temperature falls below a predetermined level, air can circulate more easily inside and outside the housing 12, and the decrease in temperature inside the housing 12 can be suppressed.

[0033] In the above embodiments 1 and 2, the rotating body 20 had a roughly spherical shape, but the invention is not limited to this configuration. For example, as shown in Figure 2(b), the rotating body 20a may have grooves 21a formed on its surface. In Figure 2(b), the rotating body 20a has two grooves 21a, but the number of grooves 21a formed on the rotating body 20a is not limited. By forming grooves 21a on the surface of the rotating body 20a, the gap between the rotating body 20a and the through hole 14 becomes larger. As a result, air can pass through the through hole 14 more easily, improving ventilation. Also, by forming grooves 21a on the surface of the rotating body 20a, the contact area between the rotating body 20a and the through hole 14 becomes smaller. As a result, friction when the rotating body 20a rotates is reduced, and the rotation of the rotating body 20a is less likely to be suppressed.

[0034] (Example 3) In the above embodiments 1 and 2, the rotating body 20 was supported by the through hole 14, but the configuration is not limited to this. As shown in Figure 3, the rotating body 120 of the protective structure 110 may be supported by the rotating shaft 124. Note that in Figure 3, multiple battery packs housed in the housing 112 are shown together as a single protected object 50.

[0035] The rotating body 120 is approximately spherical (see Figure 2(a)) and has a linear hole passing through its center. The rotating shaft 124 is cylindrical and passes through the hole formed in the rotating body 120. In this embodiment, three rotating bodies 120 are supported by one rotating shaft 124, and the three rotating bodies 120 are arranged in series with respect to one rotating shaft 124. The one rotating shaft 124 and the three rotating bodies 120 are integrally formed.

[0036] Multiple through holes 114 are formed on the side of the housing 112. Each through hole 114 extends in a direction perpendicular to the side and penetrates the side. Inside the side of the housing 112, there is a hole 116 that extends parallel to the side. A rotating body 120 is placed in each through hole 114, and a rotating shaft 124 is placed in the hole 116. The rotating body 120 is supported by the rotating shaft 124 so as to be rotatable around the rotating shaft 124 within the through hole 114. That is, the through hole 114 is slightly larger than the outer shape of the rotating body 120 and has a shape that follows the outer shape of the rotating body 120. Similarly, the hole 116 is slightly larger than the outer shape of the rotating shaft 124 and has a shape that follows the outer shape of the rotating shaft 124. Therefore, the rotating shaft 124 is positioned along the side of the housing 12 (i.e., the hole 116) and extends in a direction perpendicular to the direction of penetration of the through hole 114. Since the one rotation axis 124 and the three rotating bodies 120 are integrally formed, the one rotation axis 124 and the three rotating bodies 120 rotate integrally around the rotation axis 124.

[0037] In this embodiment, one rotating shaft 124 supports three rotating bodies 120, but the configuration is not limited to this. One rotating shaft 124 may support one or two rotating bodies 120. Also, if there are four or more through holes 114 formed on the side surface of the housing 112, one rotating shaft 124 may support four or more rotating bodies 120.

[0038] In this embodiment as well, by placing the rotating body 120 inside the through hole 114, it is possible to prevent foreign matter 52 from passing through the through hole 114 and entering the housing 12. Furthermore, in this embodiment, the rotating body 120 rotates around the rotation axis 124. As a result, the rotating body 120 rotates in a constant direction and rotates stably. This makes it possible to form a constant gap between the through hole 114 and the rotating body 120.

[0039] In this embodiment, the rotating body 120 and the rotating shaft 124 were integrally formed, but the configuration is not limited to this. For example, the rotating body 120 may be a separate component from the rotating shaft 124. In this case, the rotating shaft 124 may be fixed within the hole 116, and only the rotating body 120 may be rotatable around the rotating shaft 124.

[0040] Furthermore, as shown in Figure 4(b), in this embodiment as well, grooves 121a may be formed on the surface of the rotating body 120a. The number of grooves 121a formed on the surface of the rotating body 120a is not limited. By forming grooves 121a on the surface of the rotating body 120a, the gap between the rotating body 120a and the through hole 114 becomes larger, and the area in contact between the rotating body 120a and the through hole 114 becomes smaller. As a result, ventilation is improved, friction when the rotating body 120a rotates is reduced, and the rotation of the rotating body 120a is less likely to be suppressed.

[0041] (Example 4) In the above embodiments 1 to 3, the rotating bodies 20 and 120 were substantially spherical, but the configuration is not limited to this. As long as the rotating body can rotate within the through hole, for example, as shown in Figure 5, the rotating body 220 may be cylindrical.

[0042] The housing 212 of the protective structure 210 has a through hole 214 formed therein, and a rotating body 220 is positioned within the through hole 214. The rotating body 220 is cylindrical and has a hole formed through its center. A rotating shaft 224 is positioned in the hole formed in the rotating body 220. The rotating shaft 224 is positioned along the side surface within the side surface of the housing 12 and extends in a direction perpendicular to the through-direction of the through hole 214. The through hole 214 is slightly larger than the rotating body 220. Specifically, the through hole 214 is larger than the axial dimension of the rotating body 220 and smaller than the axial dimension of the rotating shaft 224. The rotating body 220 is rotatably supported in the housing 212 by the rotating shaft 224. The rotating body 220 may be formed integrally with the rotating shaft 224, or it may be a separate part from the rotating shaft 224.

[0043] As in this embodiment, even when the rotating body 220 is formed in a cylindrical shape, by placing the rotating body 220 inside the through hole 214, it is possible to suppress the intrusion of foreign matter 52 into the housing 212 while ensuring ventilation. Furthermore, because the rotating body 220 is formed in a cylindrical shape, the through hole 214 can be made larger, thereby improving ventilation.

[0044] In this embodiment, the rotating body 220 was supported by the rotating shaft 224, but the configuration is not limited to this. If the through hole 214 is formed in a shape that conforms to the rotating body 220, the rotating body 220 will be supported by the through hole 214. Therefore, the rotating body 220 does not need to be supported by the rotating shaft 224, and the rotating shaft 224 does not need to be present at all.

[0045] Furthermore, while the rotating bodies 20 and 120 in Examples 1 to 3 above were substantially spherical, and the rotating body 220 in Example 4 above was substantially cylindrical, the configuration is not limited to these. As long as it can rotate within a through hole formed in the housing, its shape is not limited. For example, the rotating body may be flattened or lenticular.

[0046] Furthermore, in the above embodiments 1 to 4, the protected object protected by the protective structures 10, 110, and 210 was the battery cell 50, and the housing that accommodates the protected object was the casing 12 that accommodates the battery cell 50. However, the configuration is not limited to this. As long as the protected object is housed in a housing with through holes, the same configuration as the protective structures 10, 110, and 210 in the above embodiments 1 to 4 can be applied.

[0047] For example, the same configuration as the through-holes 14, 114, 214 and rotating bodies 20, 120, 220 of the above-described embodiments 1 to 4 may be applied to ventilation openings formed in the exterior wall of a building. In this case as well, by arranging the rotating bodies 20, 120, 220 inside the through-holes 14, 114, 214, it is possible to ensure ventilation of the through-holes 14, 114, 214 while suppressing the entry of foreign matter into the building. Alternatively, the same configuration as in embodiment 1 may be applied, and the rotating bodies 20, 120, 220 may be formed from a material that increases the gap between the through-holes 14, 114, 214 and the rotating body 20 when the temperature rises above a predetermined temperature. In this case, the predetermined temperature is, for example, the temperature when the temperature inside the building rises due to a fire. When the temperature rises above the predetermined temperature, the gap between the through-holes 14, 114, 214 and the rotating body 20 increases, making it easier for carbon monoxide generated by the fire to be discharged outside the building.

[0048] Furthermore, the same configuration as the through-holes 14, 114, 214 and rotating bodies 20, 120, 220 of the above-described examples 1 to 4 may be applied to the water inlets and outlets of fish farms and aquaculture plants. In this case as well, by arranging the rotating bodies 20, 120, 220 inside the through-holes 14, 114, 214, it is possible to ensure ventilation while suppressing the entry of foreign matter into the fish farms and aquaculture plants. In particular, if the gap between the through-holes 14, 114, 214 and the rotating bodies 20, 120, 220 is designed to be larger than plankton but smaller than foreign matter such as garbage, it is possible to allow plankton and water (or seawater) to pass through the fish farms and aquaculture plants while suppressing the passage of foreign matter such as garbage. Furthermore, if the rotating bodies 20, 120, and 220 are made of an opaque material, fish in the fish farm or aquaculture facility will perceive the rotating bodies 20, 120, and 220 as walls or nets, making it difficult for them to enter the through-holes 14, 114, and 214.

[0049] The specific examples of the technology disclosed herein have been described in detail above, but these are merely illustrative and do not limit the scope of the claims. The technology described in the claims includes various modifications and changes to the specific examples described above. Furthermore, the technical elements described herein or in the drawings exhibit technical usefulness individually or in various combinations, and are not limited to the combinations described in the claims at the time of filing. In addition, the technology illustrated herein or in the drawings achieves multiple objectives simultaneously, and achieving even one of these objectives itself constitutes technical usefulness. [Explanation of Symbols]

[0050] 10, 110, 210: Protective structure 12, 112, 212: Enclosure 14, 114, 214: Through holes 20, 20a, 120, 120a, 220: Rotating bodies 21a, 121a: Groove 124, 224: Rotation axis 50: Battery cell 52: Foreign matter

Claims

1. A housing section for housing the protected object, A through hole is provided on the outer surface of the housing portion, and penetrates between the inside and outside of the outer surface, A protective structure comprising a rotating body disposed within the through hole and supported so as to be rotatable within the through hole.

2. The protective structure according to claim 1, The rotating body is a protective structure formed of a material that increases the gap between the through hole and the rotating body when a predetermined threshold temperature is exceeded.

3. The protective structure according to claim 1, The rotating body is a protective structure formed of a material that reduces the gap between the through hole and the rotating body when a predetermined threshold temperature is exceeded.

4. The protective structure according to claim 1, The rotating body is a spherical protective structure.

5. The protective structure according to claim 1, The rotating body is further provided with a rotating shaft that penetrates the center of the rotating body and extends along the outer surface, The rotating body is a protective structure that rotates around the axis of rotation.

6. The protective structure according to claim 5, The rotating body has a straight hole passing through the center, The rotating shaft is a protective structure positioned in the hole.

7. The protective structure according to claim 5, The rotating body and the rotating shaft are integrally formed protective structure.

8. A protective structure according to claim 4 or 5, The rotating body is a protective structure having grooves formed on its surface.

Images