Ventilation parts

Abstract

A ventilation component 1 includes a ventilation passage 10 for ventilation between an interior space 2u and an exterior space 2s of a housing 2. The ventilation passage 10 is a passage for ventilation between the interior space 2u and the exterior space 2s when the ventilation component 1 is mounted on an edge 2f. The ventilation component 1 includes a support part 12, a ventilation film 11, a protruding part 13, and a seal member 14. The support part 12 surrounds the ventilation passage 10. The ventilation film 11 is fixed to the support part 12 and blocks the ventilation passage 10 in a breathable manner. The protruding part 13 is formed so as to protrude from the support part 12 and surround one end of the ventilation passage 10. The protruding part 13 is a cylindrical part that contacts the edge 2f when the ventilation component 1 is mounted on the edge 2f. The ventilation component 1 satisfies the condition of 0.7 ≤ D / W ≤ 1.3.

Description

[Technical field]

[0001] The present invention relates to a ventilation component. [Background technology]

[0002] Conventionally, ventilation parts are known that are attached to the edge of an opening of a housing having an opening. The ventilation parts can be used to eliminate pressure differences that occur inside the equipment due to temperature changes in equipment such as automobile lamps, inverters, converters, electronic control units (ECUs), battery packs, millimeter wave radars, and in-vehicle cameras. In such equipment, it can be required to prevent substances such as foreign matter, water, oil, and salt from entering the equipment. In response to such requirements, ventilation parts are attached to the housing of the equipment.

[0003] For example, Patent Document 1 describes a ventilation unit including a ventilation member attached to an opening of a housing, a sealing member, and a washer. The sealing member seals the gap between the housing and the ventilation member. The washer is a ring-shaped member surrounding the sealing member. This configuration can prevent foreign matter from entering the housing through the gap between the ventilation member and the housing even in an environment where high external pressure acts due to, for example, the injection of high-pressure water to an automobile electrical component.

[0004] Patent Document 2 describes a ventilation structure including a housing, a ventilation member, and a sealing member. The housing has an opening. The ventilation member is attached to the opening of the housing. The sealing member is held by the ventilation member. The opening has a tapered surface. The ventilation member includes a support having an air passage, a waterproof air-permeable membrane that blocks the air passage, and a cover that covers the waterproof air-permeable membrane. The sealing member seals the gap between the housing and the support around the air passage. The support has a pressing part that presses the sealing member against the tapered surface. According to this configuration, the sealing member is contained within the opening, so that it is possible to prevent water from the outside from directly contacting the sealing member due to reasons such as the injection of high-pressure water to an automobile electrical component.

[0005] Patent Document 3 describes a ventilation structure including an opening in a housing, a ventilation member, and a shield. The ventilation member is fixed to the opening and includes a ventilation membrane. The shield is a protrusion formed on the surface of the housing. According to the ventilation structure described in Patent Document 3, when this ventilation structure is applied to an ECU in an engine room of an automobile, durability against water flow during high-pressure washing of the engine room is improved. Since the shield blocks part of the water flow, the water pressure applied to the ventilation member can be reduced. [Prior art documents] [Patent documents]

[0006] [Patent Document 1] JP 2012-231089 A [Patent Document 2] JP 2012-243536 A [Patent Document 3] JP 2007-048585 A Summary of the Invention [Problem to be solved by the invention]

[0007] The techniques described in Patent Documents 1 to 3 require a washer, an opening with a tapered surface, or a shield, which imposes restrictions on the design and manufacture of the ventilation structure.

[0008] Therefore, the present invention provides a ventilation component that can prevent water from entering the inside of a housing when it is subjected to a high-pressure water flow, while reducing constraints in design and manufacturing. [Means for solving the problem]

[0009] The present invention relates to A ventilation part that is attached to an edge of an opening that communicates an internal space and an external space of a housing, a ventilation passage for ventilating between the internal space and the external space when the ventilation part is attached to the edge; A support portion surrounding the air passage; An air permeable membrane that is fixed to the support portion and closes the air passage in an air permeable manner; a cylindrical protrusion that protrudes from the support portion and is formed to surround one end of the ventilation passage and that contacts the edge when the ventilation component is attached to the edge; a seal member disposed around the protrusion and configured to seal a gap between an outer surface of the housing and the ventilation part when the ventilation part is attached to the edge; A distance D from an outer end of the outer surface of the support portion in contact with the protrusion to a boundary between the protrusion and the support portion when the outer surface is viewed in plan, and a line diameter W of the seal member satisfy the condition of 0.7≦D / W≦1.3. Provide ventilation components. Effect of the Invention

[0010] According to the above ventilation part, it is possible to reduce restrictions in designing and manufacturing the ventilation structure, and in addition, the above ventilation part can prevent water from entering the inside of the housing when it is subjected to a high-pressure water flow. [Brief description of the drawings]

[0011] [Figure 1] FIG. 1 is a cross-sectional view showing an example of a ventilation part according to the present invention. [Figure 2A] FIG. 2A is a cross-sectional view showing an example of a ventilation structure provided by the ventilation component shown in FIG. [Figure 2B] FIG. 2B is a cross-sectional view showing an example of a ventilation structure provided by a ventilation part according to a comparative example. [Diagram 3] FIG. 3 is a plan view showing a specific portion of the ventilation part shown in FIG. [Figure 4] FIG. 4 is a cross-sectional view showing a part of the ventilation component shown in FIG. [Diagram 5] FIG. 5 is a cross-sectional view showing another example of a ventilation part according to the present invention. [Figure 6] FIG. 6 is a cross-sectional view showing the ventilation parts used in the examples and comparative examples. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0012] Hereinafter, an embodiment of the present invention will be described with reference to the accompanying drawings. The following description is an example of the present invention, and the present invention is not limited to the following embodiment.

[0013] As shown in FIG. 1 and FIG. 2A, the ventilation part 1 is attached to the edge 2f of the opening 21 that communicates the internal space 2u and the external space 2s of the housing 2. The ventilation part 1 has an air passage 10. The air passage 10 is a path for ventilation between the internal space 2u and the external space 2s when the ventilation part 1 is attached to the edge 2f. The ventilation part 1 includes a support part 12, a ventilation film 11, a protruding part 13, and a seal member 14. The support part 12 surrounds the ventilation path 10. The ventilation film 11 is fixed to the support part 12 and closes the ventilation path 10 in a breathable manner. The protruding part 13 is formed so as to protrude from the support part 12 and surround one end of the ventilation path 10, and is a cylindrical part that contacts the edge 2f when the ventilation part 1 is attached to the edge 2f. The seal member 14 is disposed around the protrusion 13 and seals the gap between the outer surface 2g of the housing 2 and the ventilation part 1 when the ventilation part 1 is attached to the edge 2f. The ventilation part 1 satisfies the condition of 0.7≦D / W≦1.3. FIG. 3 is a plan view of a portion of the support part 12 between the outer end 12e of the outer surface 12g of the support part 12 contacting the protrusion 13 and the boundary 12b between the protrusion 13 and the support part 12 when the outer surface 12g of the support part 12 contacting the protrusion 13 is viewed in plan. As shown in FIG. 3, D is the distance from the outer end 12e to the boundary 12b. As shown in FIG. 4, W is the wire diameter of the seal member 14.

[0014] As shown in Fig. 2A, a ventilation structure 50 can be provided by attaching the ventilation part 1 to the edge 2f of the opening 21 of the housing 2. Fig. 2B shows a ventilation structure 50a provided by using a ventilation part 1a according to a comparative example. The ventilation part 1a is configured in the same manner as the ventilation part 1, except for parts that will be particularly described. The same reference numerals are used to denote components of the ventilation part 1a that are the same as or correspond to the components of the ventilation part 1.

[0015] For example, German Industrial Standard DIN 400 50 Part 9 describes a waterproof test involving spraying high-temperature, high-pressure water at angles of 30° and 60° against a product. In the ventilation structure 50a, from the viewpoint of protecting the seal member 14 from such an oblique water flow J1, the seal member 14 is disposed in a position recessed from the outside of the ventilation structure 50. For this reason, in the ventilation part 1a, the D / W is adjusted to a value greater than 1.3. This makes it difficult for the seal member 14 to be directly subjected to the water flow J1. Thus, in the past, it was considered natural to set the D / W value of the ventilation part to be significantly greater than 1.3 from the viewpoint of waterproofness against spraying of high-temperature, high-pressure water.

[0016] On the other hand, according to the study by the present inventors, it has been found that when a high-pressure water flow J2 occurs toward the seal member 14 of the ventilation part 1a, a large value of D / W is not advantageous in terms of promoting drainage from around the seal member 14. This is because the space between the support part 12 of the ventilation part 1a and the outer surface 2g of the housing 2 around the seal member 14 becomes long, and high water pressure continues to be applied to that space when a high-pressure water flow J2 occurs toward the seal member 14. If high water pressure continues to be applied to the seal member 14, unintended deformation of the seal member 14 may occur, and water may enter the inside of the housing 2.

[0017] In order to prevent the sealing member from being subjected to high water pressure, it is possible to apply the techniques described in Patent Documents 1 to 3. However, the techniques described in Patent Documents 1 to 3 require a washer, an opening with a tapered surface, or a shield, which creates restrictions in the design and manufacture of the ventilation structure. For example, the techniques described in Patent Documents 1 to 3 are not advantageous in terms of high design freedom and reduced manufacturing costs. Therefore, the present inventors have conducted extensive research to develop a new ventilation part that can prevent water from entering the inside of a housing when it is subjected to a high-pressure water flow while reducing restrictions in the design and manufacture of the ventilation structure. As a result, they have newly discovered that by adjusting the D / W value of the ventilation part to the above range, it is possible to prevent water from entering the inside of a housing when it is subjected to a high-pressure water flow while reducing restrictions in design and manufacture.

[0018] Because the ventilation part 1 satisfies the condition 0.7≦D / W≦1.3, when a high-pressure water flow occurs toward the sealing member 14 in the ventilation structure 50, the water can easily escape from around the sealing member 14 as shown in Fig. 2A, and drainage can be promoted around the sealing member 14. As a result, it is possible to prevent high water pressure from being continuously applied to the sealing member 14, and to prevent water from entering the housing 2.

[0019] The value of D may be constant or may vary around the axis A1 of the ventilation part 1. When the value of D varies around the axis A1, for example, the condition 0.7≦D / W≦1.3 is satisfied in a region of 50% or more of the entire circumference of 360° around the axis A1. This region may exist continuously around the axis A1, or may exist in a plurality of separate regions. Desirably, the condition 0.7≦D / W≦1.3 is satisfied in a region of 60% or more of the entire circumference of 360° around the axis A1. More desirably, the condition 0.7≦D / W≦1.3 is satisfied in a region of 70% or more of the entire circumference of 360° around the axis A1. Even more desirably, the condition 0.7≦D / W≦1.3 is satisfied in a region of 80% or more of the entire circumference of 360° around the axis A1. It is particularly desirable that the condition 0.7≦D / W≦1.3 be satisfied over 90% or more of the entire 360° circumference around the axis A1. It is particularly desirable that the condition 0.7≦D / W≦1.3 be satisfied over the entire 360° circumference around the axis A1.

[0020] The wire diameter W typically corresponds to the maximum dimension of the cross section of the seal member 14 along a plane including the axis A1 in a direction perpendicular to the axis A1. The value of the wire diameter W is typically constant around the axis A1. Note that when the difference between the maximum and minimum values ​​of the wire diameter W around the axis A1 is less than 10% of the minimum value, the value of the wire diameter W may be considered to be constant around the axis A1.

[0021] The value of D / W is not limited to a specific value as long as it satisfies the condition 0.7≦D / W≦1.3. As shown in FIG. 4, D may be equal to or greater than W, and as shown in FIG. 5, D may be less than W. The value of D / W may be equal to or greater than 0.75, equal to or greater than 0.8, or equal to or greater than 0.85. The value of D / W may be equal to or less than 1.25, equal to or less than 1.2, or equal to or less than 1.15.

[0022] The value of the wire diameter W is not limited to a specific value as long as the condition 0.7≦D / W≦1.3 is satisfied. The value of the wire diameter W is, for example, 2.8 mm or more and 6.0 mm or less. In this case, in the ventilation structure 50, the contact area between the seal member 14 and the support part 12 and the contact area between the seal member 14 and the outer surface 2g of the housing 2 tend to be large. Therefore, in the ventilation structure 50, when a high-pressure water flow is generated toward the seal member 14, it is possible to more reliably prevent water from entering the inside of the housing 2.

[0023] The wire diameter W may be 2.9 mm or more, 3.0 mm or more, 3.2 mm or more, 3.4 mm or more, 3.6 mm or more, 4.0 mm or more, or 4.5 mm or more. The wire diameter W may be 5.9 mm or less, 5.6 mm or less, 5.3 mm or less, or 4.8 mm or less.

[0024] The value of the distance D is not limited to a specific value as long as the condition 0.7≦D / W≦1.3 is satisfied. The value of the distance D is, for example, 1.96 mm or more and 7.8 mm or less.

[0025] The value of the distance D may be 2.2 mm or more, 2.4 mm or more, 2.6 mm or more, 2.8 mm or more, 3.0 mm or more, 3.2 mm or more, or 3.5 mm or more. The value of the distance D may be 7.5 mm or less, 7.0 mm or less, 6.5 mm or less, or 6.0 mm or less.

[0026] The shape of the seal member 14 is not limited to a specific shape. The seal member 14 is typically an annular member. A cross section obtained by cutting the seal member 14 along a plane including the axis of the seal member 14 is, for example, a circle, an ellipse, or a plane having corners. The plane having corners may be a polygon or a figure combining curved lines and straight lines. The seal member 14 may have a hollow structure having an annular internal space.

[0027] As shown in FIG. 4, the seal member 14 has, for example, an inclined portion 14k. The inclined portion 14k forms an inclined surface between a first position 14f and a second position 14s located on the outer periphery of the seal member 14. The second position 14s is located closer to the support portion 12 than the first position 14f, and is located closer to the boundary 12b than the first position 14f. With this configuration, in the ventilation structure 50, when a high-pressure water flow occurs toward the seal member 14, the water flow is likely to be guided in a direction away from the outer surface 2g of the housing 2 after colliding with the inclined portion 14k. This makes it easy to promote drainage around the seal member 14. The first position 14f is located, for example, at the outer end of the seal member 14 in a direction perpendicular to the axis of the seal member 14.

[0028] As shown in FIG. 1, the protrusion 13 includes, for example, a plurality of legs 13a. The plurality of legs 13a are spaced apart from each other around the central axis of the protrusion 13 by slits 13s extending from the tip of the protrusion 13 along the central axis of the protrusion 13. At least one of the plurality of legs 13a has an engagement portion 13k that engages with the housing 2. The engagement portion 13k protrudes outward in a direction perpendicular to the central axis of the protrusion 13. According to this configuration, when the tip of the protrusion 13 contacts the edge 2f during mounting of the ventilation part 1 to the housing 2, including inserting the protrusion 13 into the opening 21, the leg 13a is elastically deformed inward. After that, when the engagement portion 13k passes through the opening 21, the deformation of the leg 13a is released, and the engagement portion 13k contacts, for example, the inner surface 2n of the housing 2. In this manner, the engagement portion 13k engages with the housing 2 by snap-fitting, and the ventilation part 1 is mounted on the edge 2f of the housing 2.

[0029] The support portion 12 and the protrusion portion 13 may be integrally molded parts, or the support portion 12 and the protrusion portion 13 may be separately manufactured parts. The material of the support portion 12 and the protrusion portion 13 is, for example, a thermoplastic resin from the viewpoint of moldability. The thermoplastic resin may be, for example, polyamide (PA), polyethylene terephthalate (PET), polyphenylene sulfide (PPS), polybutylene terephthalate (PBT), polycarbonate (PC), polypropylene (PP), polyphenylene ether (PPE), and a thermoplastic elastomer. The material of the support portion 12 and the protrusion portion 13 may be a thermosetting resin or a metal. The material of the support portion 12 and the protrusion portion 13 may be rubber. The rubber is, for example, nitrile butadiene rubber (NBR), ethylene propylene rubber (EPDM), silicone rubber, fluororubber, acrylic rubber, or hydrogenated nitrile rubber.

[0030] 1, the support 12 typically has a mounting surface 12s to which the breathable membrane 11 is attached. The mounting surface 12s is, for example, an annular surface. The breathable membrane 11 is disposed, for example, along a direction perpendicular to the central axis of the protrusion 13.

[0031] The breathable membrane 11 is not limited to a specific breathable membrane as long as it has the desired breathability. The breathable membrane 11 may be a single layer membrane or a multilayer membrane. When the breathable membrane 11 is a multilayer membrane, each layer may be one selected from the group consisting of a porous membrane, a nonwoven fabric, a cloth, and a mesh. The breathable membrane 11 may include a porous membrane and a nonwoven fabric, may include at least one of a cloth and a mesh and a porous membrane, or may include a plurality of nonwoven fabrics. The breathable membrane 11 is typically composed of an organic polymer material (resin). The material of the porous membrane is, for example, a fluororesin. As the fluororesin, for example, polytetrafluoroethylene (PTFE), polychlorotrifluoroethylene, tetrafluoroethylene-hexafluoropropylene copolymer, or tetrafluoroethylene-ethylene copolymer can be used. The material of the porous membrane may be a polyolefin such as a polymer or copolymer of a monomer such as ethylene, propylene, and 4-methylpentene-1,1 butene. The porous membrane may be a nanofiber porous membrane such as polyacrylonitrile, nylon, or polylactic acid. The porous membrane can be manufactured by known drawing or extraction methods. Materials for nonwoven fabrics, cloths, and meshes include, for example, polyesters such as polyethylene terephthalate, polyolefins such as polyethylene and polypropylene, nylon, aramid, or ethylene vinyl acetate copolymers.

[0032] The breathable membrane 11 preferably includes a PTFE porous membrane. The PTFE porous membrane can ensure breathability even in a small area and can effectively prevent the intrusion of foreign matter. The PTFE porous membrane may be laminated on a breathable support material such as a nonwoven fabric.

[0033] The gas-permeable membrane 11 may be subjected to a liquid-repellent treatment as necessary. The liquid-repellent treatment is performed, for example, by forming a liquid-repellent coating containing a fluorine-based surface modifier having a perfluoroalkyl group on the gas-permeable membrane 11. The method for forming the liquid-repellent coating is not limited to a specific method. The liquid-repellent coating is formed by coating the resin porous membrane with a solution or dispersion of a fluorine-based surface modifier having a perfluoroalkyl group by a method such as air spraying, electrostatic spraying, dip coating, spin coating, roll coating, curtain flow coating, or impregnation. The liquid-repellent coating may also be formed by electrodeposition coating or plasma polymerization.

[0034] The breathable membrane 11 is, for example, adhered to the adherend surface 12s. The breathable membrane 11 may be welded to the adherend surface 12s. As a welding method, heat welding, ultrasonic welding, and laser welding may be used. In addition, when molding the support part 12, the breathable membrane 11 may be attached to the adherend surface 12s by insert molding in which a resin is poured into a mold with the breathable membrane 11 placed at a predetermined position inside the mold for molding. The breathable membrane 11 may be attached to the adherend surface 12s by double-sided tape.

[0035] The material of the seal member 14 is not limited to a specific material as long as it can exhibit the desired sealing properties. For example, the materials exemplified as the materials of the support portion 12 and the protrusion portion 13 can be used as the material of the seal member 14. The seal member 14 is typically an elastic body that is elastically deformable, and the material of the seal member 14 can be an elastomer such as natural rubber, synthetic rubber, or a thermoplastic elastomer.

[0036] 1, the ventilation part 1 further includes, for example, a cover 16. The cover 16 is connected to the support part 12. The cover 16 covers the ventilation membrane 11 and forms a space 17 between the cover 16 and the ventilation membrane 11, the space 17 being in communication with the external space of the ventilation part 1. The space 17 forms a part of the ventilation path 10. This allows the ventilation membrane 11 to be appropriately protected.

[0037] The cover 16 may be a part that is molded integrally with the support part 12, or may be a part that is produced separately from the support part 12. As the material of the cover 16, for example, the materials exemplified as the material of the support part 12 can be used.

[0038] At least one of the support part 12 and the cover 16 may have a side wall 18 arranged on the outer periphery of the space 17. The side wall 18 may include a plurality of side walls arranged at a predetermined interval in the circumferential direction. Each of the support part 12 and the cover 16 may have a plurality of side walls arranged at a predetermined interval in the circumferential direction. In this case, the side wall of the support part 12 and the side wall of the cover 16 may partially overlap in the circumferential direction.

[0039] In the ventilation structure 50, the housing 2 is, for example, a housing for an electronic device. The electronic device is, for example, an electronic device for an automobile, such as an automobile lamp, an electronic control unit (ECU), an electric power system (EPS), a battery pack, an inverter, a converter, a millimeter wave radar, and an in-vehicle camera. The electronic device may be used for purposes other than automobiles. According to the ventilation structure 50, the pressure difference generated between the internal space 2u and the external space 2s of the housing 2 due to a temperature change can be eliminated by the ventilation path 10. In addition, since the ventilation film 11 closes the ventilation path 10 in a breathable manner, it is possible to prevent foreign matter from entering the internal space 2u, and for example, the ventilation structure 50 has dustproof properties. In addition, the ventilation structure 50 can prevent water, oil, salt, and the like from entering the internal space 2u. EXAMPLES

[0040] The present invention will be described in more detail below using examples, but the present invention is not limited to the following examples.

[0041] By processing the outer surface of the support part of the TEMISH Z series Z3-NTF210SE ventilation part manufactured by Nitto Denko Corporation shown in Figure 6, ventilation parts with distances D from the outer edge of the outer surface of the support part to the boundary between the protruding part and the support part of 1.5 mm, 1.8 mm, 2.5 mm, 3.0 mm, 3.5 mm, 4.0 mm, and 5.0 mm were prepared. As shown in Figure 6, in the ventilation part before processing, the outer diameter of the protruding part was 10 mm, and the outer diameter of the engagement part was 12.4 mm. TEMISH is a registered trademark of Nitto Denko Corporation. An O-ring α with a wire diameter W2.40 mm and an O-ring β with a wire diameter W3.85 mm were prepared. The hardness of the O-ring α and the O-ring β was measured using a type A durometer, and the hardness of the O-ring α was 70, and the hardness of the O-ring β was 50. An O-ring α or an O-ring β was attached to each of the processed ventilation parts, and as shown in Table 2, samples according to Examples 1 to 4 and samples according to Comparative Examples 1 to 4 were prepared.

[0042] <Water resistance test> The protruding portion of each sample according to Examples 1 to 4 and Comparative Examples 1 to 4 was inserted and fixed into a housing having a circular opening with a diameter of 10.4 mm. The compression ratio of the O-ring α or O-ring β when each sample was fixed into the housing (O-ring compression ratio [%] = O-ring crushing allowance (length in the compression direction when compressed) / O-ring wire diameter W × 100) was 15%. A water resistance test (main test) was performed on each of the samples according to Examples 1 to 4 and Comparative Examples 1 to 4 in accordance with the German Industrial Standard DIN400 50 Part 9, except for the change to the conditions in Table 1, and the presence or absence of water penetration was visually confirmed. The results are shown in Table 2.

[0043] [Table 1]

[0044] [Table 2]

Claims

1. A ventilation part that is attached to an edge of an opening that communicates an internal space and an external space of a housing, a ventilation passage for ventilating between the internal space and the external space when the ventilation part is attached to the edge; A support portion surrounding the air passage; An air permeable membrane that is fixed to the support portion and closes the air passage in an air permeable manner; a protrusion that protrudes from the support portion, includes a cylindrical portion that surrounds a part of the ventilation path and is in contact with the support portion, and that contacts the edge when the ventilation component is attached to the edge; a sealing member (excluding a sealing member having an annular inner peripheral portion, an annular outer peripheral portion provided outside the inner peripheral portion, and an annular recessed portion provided between the inner peripheral portion and the outer peripheral portion) that is disposed around the protruding portion and seals a gap between the outer surface of the housing and the ventilation part when the ventilation part is attached to the edge, When the outer surface of the support part in contact with the protrusion is viewed in plan, a distance D from an outer end of the outer surface to a boundary between the protrusion and the support part and a line diameter W of the seal member satisfy the condition of 0.75≦D / W≦1.25 around the entire circumference of the axis of the seal member before the ventilation part is attached to the edge. Ventilated parts.

2. A ventilation part that is attached to an edge of an opening that communicates an internal space and an external space of a housing, a ventilation passage for ventilating between the internal space and the external space when the ventilation part is attached to the edge; A support portion surrounding the air passage; An air permeable membrane that is fixed to the support portion and closes the air passage in an air permeable manner; a protrusion that protrudes from the support portion, includes a cylindrical portion that surrounds a part of the ventilation path and is in contact with the support portion, and that contacts the edge when the ventilation component is attached to the edge; a seal member disposed around the protrusion and configured to seal a gap between an outer surface of the housing and the ventilation part when the ventilation part is attached to the edge; a cross section obtained by cutting the seal member along a plane including an axis of the seal member is a circle or an ellipse, When the outer surface of the support part in contact with the protrusion is viewed in plan, a distance D from an outer end of the outer surface to a boundary between the protrusion part and the support part and a line diameter W of the seal member satisfy the condition of 0.75≦D / W≦1.25 around the entire circumference around the axis before the ventilation part is attached to the edge. Ventilated parts.

3. The ventilation part according to claim 1 or 2, wherein the wire diameter W is 2.8 mm or more and 6.0 mm or less.

4. The ventilation part according to any one of claims 1 to 3, wherein the distance D is equal to or greater than 1.96 mm and equal to or less than 7.8 mm.

5. The ventilation part according to any one of claims 1 to 4, wherein the protrusion has an engagement portion that engages with the housing.

6. The ventilation part according to any one of claims 1 to 5, further comprising a cover that covers the ventilation membrane and forms a space between the ventilation membrane and the cover that communicates with an external space of the ventilation part.

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