Ventilation structure of on-vehicle device

Abstract

To provide a ventilation structure which achieves sufficient waterproofness and dust resistance together with air permeability without providing a ventilation member and a ventilation mechanism in a manner that these components protrude in a housing outer direction and also achieves lower manufacturing costs.SOLUTION: In a ventilation structure, an inner vent hole 20 provided on a housing inner wall surface 5 of a housing 1 and an outer vent hole 21 provided on a housing outer wall surface 6 communicate through a wall inner ventilation passage 18 provided at a wall inner part 7 of the housing.SELECTED DRAWING: Figure 1

Description

[Technical Field]

[0001] The present invention relates to a ventilation structure and a ventilation member for an in-vehicle device. [Background technology]

[0002] Conventionally, the housings of vehicle lighting fixtures such as headlamps, rear lamps, and lid lamps, in-vehicle devices such as electronic control devices, battery packs, radars, and cameras, and various electronic devices for home, medical, and office use, require ventilation between the interior and exterior of the housing to eliminate pressure differences that occur between the interior and exterior of the housing due to temperature changes. Vehicle lighting fixtures also face the problem of fogging of lenses due to condensation inside the lamp body, requiring ventilation to quickly eliminate fogging. While these devices are provided with ventilation holes to ensure ventilation, they also require dustproofness to prevent foreign objects from entering the housing through the ventilation holes and waterproofness to prevent water from entering. Therefore, ventilation members or ventilation structures with these breathable, dustproof, and waterproof properties are installed in the devices.

[0003] Here, we will explain a vehicle lamp, which, among other in-vehicle devices, is required to eliminate the pressure difference between the inside and outside of the housing and to shorten the time it takes for lenses to defog due to condensation. The entire vehicle lamp is referred to as the lamp body, the lens portion that transmits light from the lamp body when the lamp body is attached to the vehicle body is referred to as the lens cover 2, the portion that is hidden by the vehicle body when the lamp body is attached to the vehicle body is referred to as the rear surface of the lamp body, and the resin molded portion that covers the entire rear surface of the lamp body is referred to as the housing 1. The lens cover 2 and the housing 1 are combined to form the housing interior 4, and at least one light source 3 is provided in the housing interior 4. The space between the housing interior wall 5 of the housing 1 and the housing exterior wall 6 of the housing 1 is referred to as the housing interior wall 7. In in-vehicle devices other than vehicle lamps, the entire housing is referred to as the housing 1, and the space between the housing interior wall 5 of the housing 1 and the housing exterior wall 6 of the housing is referred to as the housing interior wall 7. In such a housing structure, the housing 1 is provided with a vent that communicates between the inside and outside of the housing and circulates air. For in-vehicle devices other than vehicle lighting fixtures, the entire enclosure is referred to as the housing 1.

[0004] 10(b) and 13(a), an inner vent is provided from the inside of the housing 4 on the back of the lamp body, a cylindrical protrusion 10 is provided from the inner vent, and the inside of the cylinder communicates with the inside of the housing 4. The tip of the protrusion is covered with a cap member 11 that is attached later, and the gap between a groove on the outer surface of the protrusion and the inner surface of the cap member forms a folded-back vent path, and the opening of the cap member serves as an outer vent for outside air, and the outer vent communicates with the inner vent through the vent path, forming a folded labyrinth structure that prevents dust and water from entering the inside of the housing 4. Another example is one in which an air path is formed by a synthetic resin or rubber tube bent into an L-shape or C-shape around the protrusion, as shown in Figure 13(c).

[0005] In some cases, a filter is inserted into the ventilation path to further improve dust resistance or to prevent insects from entering the housing, and in other cases, a PTFE breathable membrane is attached to the ventilation path to further improve waterproofing. [Prior art documents] [Patent documents]

[0006] [Patent Document 1] Japanese Patent Application Laid-Open No. 2001-143524 [Patent Document 2] Japanese Patent Application Laid-Open No. 2015-207529 [Patent Document 3] Japanese Patent Application Laid-Open No. 2006-324260 [Patent Document 4] Japanese Patent Application Laid-Open No. 2010-52613 [Patent Document 5] Japanese Patent Publication No. 2022-22939 Summary of the Invention [Problem to be solved by the invention]

[0007] However, the above-mentioned conventional techniques have the following technical problems to be solved.

[0008] First, the rear of the lamp body of a vehicle lamp fixture is narrow due to the proximity of other vehicle components, such as vehicle panels. Furthermore, the rear space is limited due to the placement of a power cord connected to the light source, a socket for inserting the light source protruding from the rear of the lamp body, and a light distribution mechanism. Furthermore, in conventional technologies, the ventilation structure is provided in a tubular or vertical wall-like manner, with a ventilation passage protruding from the wall of the housing toward the exterior of the housing 13, and a cylindrical ventilation member or rubber tube attached to the end of the passage. This further limits the location of the ventilation structure to avoid interference with vehicle components. Furthermore, because water spraying toward the housing seeps in between the cylindrical opening and the outer wall of the tubular ventilation passage, the entire protruding ventilation structure must be surrounded by a waterproof wall 12, which further protrudes toward the exterior of the housing 13. Due to the protruding structure, it is not possible to provide a ventilation structure in a location that is effective in shortening the time it takes for the defogging to disappear, and a desiccant may be placed inside the housing 4, which increases the cost.

[0009] Furthermore, as shown in Figure 11(b), in the area 9 where the body 8 and housing 1 are close to each other, there is no space to install a ventilation structure by extending the ventilation path toward the vehicle body. Furthermore, in this area, the narrow gap between the lamp body housing 1 and lens 2 makes it impossible to install a ventilation mechanism inside the lamp. Therefore, a PTFE-made ventilation membrane 15, which is breathable, waterproof, and dustproof, is attached to the adhesive surface 16 of the ventilation hole 14 provided in the housing 1. However, the ventilation membrane 15 is expensive, increasing the cost of the finished product. Furthermore, the ventilation membrane has a very low rigidity and is susceptible to damage during installation or maintenance of the housing. To prevent damage, a protective cover is attached, or a ventilation path is provided toward the inside of the housing, with the ventilation membrane attached to its inner edge, resulting in a complex structure that protrudes inward. Another proposal has been made to attach a ventilation membrane made of ultra-high molecular weight polyethylene, but its large pore size raises concerns about waterproofing and dustproofing, and, like the PTFE ventilation membrane, its rigidity is very low.

[0010] Furthermore, the PTFE breathable membranes mentioned above use PFAS as a raw material, raising concerns about their toxicity to humans and ecosystems. Restrictions on their use are being tightened around the world, raising concerns about the sustainability of future production and supply. PFAS-free breathable membranes have also been developed, but they are expensive. Demand for fluorine compounds, the raw material for PTFE breathable membranes, is expanding for applications such as semiconductor manufacturing. Fluorite, the main raw material, is a natural mineral containing calcium fluoride, but its production and procurement sources are concentrated in certain countries, raising concerns about the stability of procurement, including geopolitical risks.

[0011] It is desirable to provide a ventilation structure for vehicle lighting and other in-vehicle equipment that can be provided in more effective locations by reducing protrusions to the outside 13 and inside 4 of the housing, and that is breathable, dustproof, waterproof, can reduce the time it takes for fogging due to condensation to disappear, and is rigid, has no adverse effects on the human body or the ecosystem, is free from concerns about the sustainability of production and supply, and is able to provide a ventilation structure with lower manufacturing costs. [Means for solving the problem]

[0012] The following describes the ventilation structure of the present invention for a vehicle lamp, which, among other in-vehicle equipment, requires not only breathability for eliminating pressure differences but also a reduction in the time required for lens fogging due to condensation inside the housing.

[0013] The ventilation structure of the present invention provides a ventilation structure for in-vehicle equipment, characterized in that an internal air vent (20) is provided from the internal wall surface (5) of the housing toward the inside wall (7) of the housing without penetrating the external wall surface (6) of the housing, an external air vent (21) is provided from the side of the external wall surface (6) of the housing at an appropriate position spaced apart from the position of the internal air vent (20) along the internal wall surface (5) of the housing toward the inside wall (7) of the housing without penetrating the internal wall surface (5), and an internal air passage (18) is provided in the inside wall (7) of the housing to communicate with the internal air vent (20) and the external air vent (21), thereby communicating the inside (4) of the housing with the outside (13) of the housing.

[0014] Within the in-wall air passage 18, one or more blocking walls 24 are provided to block part of the in-wall air passage 18 while ensuring some ventilation, thereby forming a first labyrinth structure 23, and the bending of the air passage by the first labyrinth structure 23 and the expansion chamber 25 formed by the blocking walls 24 ensure pressure loss of outside air entering the housing, thereby preventing water, dirt, and dust from entering the housing.

[0015] The inner walls of the in-wall air passage 18 are an inner wall 27 on the lamp chamber side and an outer wall 28 on the outside of the housing, and at least one or more outer wall barriers 33 are provided on the external air vent 21 side of the outer wall 28 of the outer wall member 19 and outer wall member 35 toward the inner wall 27 to block a part of the in-wall air passage 18 and allow a part of it to be ventilated, and at least one or more inner wall barriers 34 are provided from the inner wall 27 toward the outer wall 28 to block a part of the in-wall air passage 18 and allow a part of it to be ventilated, and the outer wall barriers 33 and the inner wall barriers 34 provide a second labyrinth structure within the in-wall air passage 18.

[0016] In the case where the environment where the vehicle is used is one with a high dust concentration or where the lamp is attached to the vehicle body and there is a concern that insects may get into the housing, a filter 22 is installed in the ventilation path 18 to prevent dust and insects from getting into the housing 4.

[0017] The outer wall members 19 and 35 are collectively referred to as the outer wall members. The outer wall members are flexible, and the pressure of the water spraying onto the outer vent 21 causes the outer wall members to bend toward the inner wall 27, blocking the opening from the outer vent 21 to the intra-wall air passage 18 and preventing water from entering the intra-wall air passage 18.

[0018] A drainage channel 54 is provided between the joint between the outer wall barrier 33 and the joint groove 36, and is connected to the ventilation port 21 so that water that has entered the enclosure can flow out from the ventilation port 21 to the outside 13 of the housing.

[0019] When water splashes on the exterior vent 21, a water film may form between the inner wall 27 and the outer wall barrier 33 due to the surface tension of the water. When the vehicle is placed in cold weather, the water film may freeze and impede the ventilation of the housing. In the present invention, a water film concentrating protrusion 42 is provided so that its tip comes into contact with the water film, which guides the water film downward and prevents it from forming between the inner wall 27 and the outer wall 28. [Effects of the Invention]

[0020] Unlike conventional cap-type and tube-type ventilation systems, the ventilation structure for vehicle-mounted equipment of the present invention does not require the ventilation path to protrude outside the housing. This eliminates the need to consider interference with other vehicle components or the body when designing the ventilation structure, greatly expanding the range of possible ventilation structures. Furthermore, the interior and exterior vents can be spaced apart, allowing the interior vent to be located in a location that is more effective in shortening the time it takes to eliminate condensation-related fogging. The exterior vent can be located without interfering with or obstructing other components. The interior and exterior vents can be connected via an in-wall ventilation path within the housing wall. Furthermore, the present invention addresses the challenges of conventional PTFE ventilation systems, such as reduced vehicle equipment costs, improved ventilation structure rigidity, and sustainability of material procurement, production, and supply. [Brief explanation of the drawings]

[0021] [Figure 1] Fig. 1(a) is a perspective view of the ventilation structure of Example 1 of the present invention installed in part B of Fig. 12, viewed from the outside 13 of the housing. Fig. 1(b) is a perspective view of the ventilation structure of Example 1 of the present invention installed in part B of Fig. 12, viewed from the inside 4 of the housing. Fig. 1(c) is a perspective view of the ventilation structure of Fig. 1(a) with an outer wall member 19 serving as the outer wall 6 of the housing removed so that the internal structure can be described. [Figure 2] Fig. 2(a) is a front view of the ventilation structure of Example 1 from outside the housing 13, Fig. 2(b) is a front view of Example 1 from inside the housing 4, Fig. 2(c) is a cross-sectional view taken along CC, Fig. 2(d) is an enlarged view of part D in Fig. 2(c), Fig. 2(e) is a view showing a state in which the outer wall member 19 is made of a flexible material, and when water is sprayed toward the outer vent 21, the end of the outer wall member 19 is bent by water pressure, and the outer wall barrier 33 blocks the outer vent 21, stopping the water. Fig. 2(f) is an enlarged view of the MM cross-section, showing a cross-sectional view of the water film aggregation protrusion 42. [Figure 3] Fig. 3(a) is a perspective view of a ventilation structure according to a second embodiment of the present invention installed in part B of Fig. 12 and viewed from the outside 13 of the housing. Fig. 3(b) is a perspective view of the ventilation structure shown in Fig. 3(a) with the outer wall member 35 forming the housing side wall 6 removed so that the internal structure can be explained. Fig. 3(c) is a view showing three internal ventilation openings 20 in the second embodiment. [Figure 4] 4(a) is a front view of the ventilation structure of Example 2 of FIG. 3 from the outside 13 of the housing, FIG. 4(b) is a front view of the ventilation structure from the inside 4 of the housing, FIG. 4(c) is an E-E cross-sectional view, FIG. 4(d) is an enlarged view of part G of FIG. 4(c), and FIG. 4(e) is an F-F cross-sectional view. [Figure 5] Fig. 5(a) is a perspective view of a ventilation structure according to a third embodiment of the present invention installed in part B of Fig. 12. Fig. 5(b) is a perspective view of the ventilation structure shown in Fig. 5(a) with the outer wall member 35 forming the housing outer wall 6 removed to enable explanation of the internal structure. Fig. 5(c) is a front view of the ventilation path Z of the third embodiment. [Figure 6] 6(a) is a front view of the ventilation structure of Example 3 of FIG. 5 from the outside 13 of the housing, FIG. 6(b) is a front view of the ventilation structure from the inside 4 of the housing, FIG. 6(c) is a cross-sectional view taken along line HH, FIG. 6(c) is an enlarged view of part J in FIG. 6(c), and FIG. 6(e) is a cross-sectional view taken along line K-K. [Figure 7] Fig. 7(a) is a front view from outside 13 of a housing provided with the ventilation structure of Example 4 in part P of Fig. 12, Fig. 7(b) is a front view from inside 4 of the housing of the ventilation structure of Example 4, Fig. 7(c) is a cross-sectional view taken along line N-N, Fig. 7(d) is a perspective view showing the internal structure with outer wall member 19 of Fig. 7(a) removed, and Fig. 7(e) is a perspective view showing the internal structure with inner wall member 51 of Fig. 7(b) removed. [Figure 8] FIG. 8 is a diagram of Example 5, in which the ventilation structure of Example 1 is provided with a detachable ventilation member at the opening of the housing 1. FIG. 8(a) is a perspective view before the outer wall member 19 is attached to the internal ventilation port 20 and the intra-wall ventilation path 18. FIG. 8(b) is a perspective view of the ventilation member 43. FIG. 8(c) is a perspective view of the back side of the ventilation member 43. FIG. 8(d) is a perspective view of the opening before the ventilation member 43 is fitted to part B in FIG. 12. FIG. 8(e) is a perspective view of the opening of FIG. 8(d) with the ventilation member 43 attached, as viewed from the outside 13 of the housing. FIG. 8(f) is a perspective view of FIG. 8(e) as viewed from inside the housing 4. [Figure 9]Fig. 9(a) is a perspective view of the housing 1 of the in-vehicle device. Fig. 9(b) is a perspective view of the housing 1 of the in-vehicle device with the top cover open. Fig. 9(c) is a front view of the housing 1 of the in-vehicle device. Fig. 9(d) is a cross-sectional view taken along the line LL. [Figure 10] Fig. 10(a) is a front view of a typical vehicle, and Fig. 10(b) is a cross-sectional view taken along line A-A. [Figure 11] Fig. 11(a) is a cross-sectional view taken along line BB in Fig. 10(a), and Fig. 11(b) is a cross-sectional view taken along line AA, including a part of the vehicle body. [Figure 12] Fig. 12(a) is a view seen from the arrow A of the lamp body in Fig. 11. Fig. 12(b) is a view seen from the arrow A of Fig. 11 in which the ventilation structure of Example 1, the ventilation structure of Example 2, and the ventilation structure of Example 4 are installed in the housing. Fig. 12(c) is a cross-sectional view taken along the line HH. [Figure 13] FIG. 12(a) shows a prior art cap vent, FIG. 12(b) shows a tortuous path vent, and FIG. 12(c) shows a rubber tube vent. DETAILED DESCRIPTION OF THE INVENTION

[0022] Hereinafter, an embodiment of the present invention will be described with reference to the drawings. The upper and lower sides are based on the state in which the vehicle equipment is installed on the vehicle. The right and left sides are based on the direction of illumination of the vehicle lamp as the front. [Example]

[0023] FIG. 1(a) is a diagram of the first embodiment, showing a perspective view of a housing 1 provided with a ventilation structure of the present invention, as viewed from the outside 13 of the housing. FIG. 1(b) is a perspective view illustrating the internal structure of a ventilation structure according to Example 1 of the present invention, with the outer wall member 19 removed. An internal ventilation port 20 from the housing interior 4 communicates with an internal ventilation channel 18 inside the housing wall 7, which in turn communicates with an external ventilation port 21. The ventilation mechanism of the present invention was installed in the area B in FIG. 12(b), where a PTFE ventilation membrane had been attached to the adjacent area 8. The ventilation structure of Example 1 was formed by molding the internal ventilation port 20 and the internal ventilation channel 18, which lacks the housing outer wall surface 6, in the mold used when molding the housing 1. The outer wall member 19 was then attached to the housing outer wall surface 6 so that a portion of the housing outer wall surface 6 was open. This opening became the external ventilation port 21, forming the ventilation structure of the present invention. The outer wall member 19 could be assembled in the same amount of time as a conventional PTFE ventilation membrane. The ventilation structure of Example 1 can be formed using a 3D printer or the like, but the above formation method was chosen in consideration of the printing process time and the work time required to remove the support material.

[0024] A shielding wall 24 and an expansion chamber 25 are provided within the ventilation path 18, forming a first labyrinth structure 23. The shielding wall 24 and the expansion chamber 25 increase the pressure loss of the airflow from the outside of the housing 13 compared to the airflow from the inside of the housing 4, providing breathability and high waterproof and dustproof properties. An ventilation path Z is formed, and this ventilation path Z connects the inside of the lamp housing 1 to the outside. The molds for the internal ventilation port 20 and the in-wall ventilation path 18 have a nested structure, so that the structure within the in-wall ventilation path 18 can be changed by replacing the nesting parts to meet the performance requirements imposed by the environment in which the on-board equipment is used.

[0025] A filter 22 can be provided inside the air passage 18. In Example 1, urethane foam was used as the material for the filter 22, but since it is protected by the outer wall member 19, any breathable and dustproof material such as nonwoven fabric, microfiber, or ultra-high molecular weight polyethylene sintered body can be used. In combination with the first labyrinth structure, this can meet the requirements for waterproofness and dustproofness that vary depending on the environment in which the vehicle body is used and the location where it is attached to the vehicle body.

[0026] In this example, the manufacturing method involves molding an internal ventilation port 20 and an in-wall ventilation passage 18 in the housing 1, fitting a filter inside the in-wall ventilation passage 18, and covering it with an outer wall member 19 molded from a thermoplastic elastomer to form the outer wall, which is then adhered with double-sided tape to produce the ventilation structure of the present invention. The outer wall member can be adhered to the housing 1 by ultrasonic welding, high-frequency welding, laser welding, or by adhesive or pressure-sensitive adhesive. Attaching the filter 22 to the outer wall member 19 before assembly improves assembly efficiency.

[0027] As shown in Figure 2(d), two exterior wall barriers 33 are provided on the outer wall 28 of the exterior wall member 19 on the exterior vent 21 side, and an interior wall barrier 34 is provided on the interior wall 27, forming a second rubble ring structure 26. The exterior wall member 19 is made of an elastic, flexible material, and as shown in Figure 2(e), it bends when water sprays from any direction, blocking the exterior vent 21 and preventing water from entering. The stronger the water pressure, the more water-resistant the structure becomes. In addition, the exterior vent peripheral wall 53 acts as a waterproof wall against water spraying into the exterior vent, eliminating the need for the conventional cylindrical ventilation path and waterproof wall 12 of the bottomed cylindrical ventilation structure.

[0028] When water gets on the exterior air vent 21, a water film forms between the inner wall 27 and the outer wall 28 due to the surface tension of the water. When the vehicle is placed in cold weather, the water film may freeze and impede ventilation. In the present invention, water film condensing protrusions 42 are provided so as to come into contact with the water film formed between the inner wall 27 and the outer wall 28, which guide the water molecules of the water film downward, causing the water film to flow downward and preventing the water film from forming between the inner wall 27 and the outer wall barrier 33.

[0029] A comparative test was conducted to compare the defogging time of the ventilation structure of Example 1 with that of a standard PTFE ventilation membrane. The PTFE ventilation membrane has an area of ​​280 square millimeters, while the narrowest cross-sectional area of ​​the inner ventilation port 20, outer ventilation port 21, and in-wall ventilation channel 18 of Example 1 is 13 square millimeters, roughly one-twentieth of the area of ​​the vent hole. The defogging time was measured using the ventilation structure of Example 1, which showed a reduction of approximately 20% compared to the PTFE ventilation membrane. [Example]

[0030] 3 and 4 are diagrams of a second embodiment of the ventilation structure of the present invention, and Fig. 3(b) is a perspective view of the inside of the ventilation structure with the outer wall member 35 removed. The inner ventilation port 20 from the inside of the housing 4 is bent inside the wall 7 of the housing and communicates with the inner-wall ventilation path 18, and the inner-wall ventilation path 18 extends and communicates with the outer ventilation port 21, so that the ventilation structure communicates between the inside of the housing 4 and the outside of the housing 13.

[0031] The outer wall member 35 is molded from EPDM rubber. Materials other than rubber can also be used. Unlike the adhesive bonding and welding of Example 1, the outer wall barrier 33 provided on the outer wall member 35 is pressed against the mating groove 36 to tightly fit and fix it. By making the outer wall member 35 round and concentrically shaped, it has a symmetrical shape in the vertical and horizontal directions. This means that the assembly direction when mating the outer wall member 35 to the housing 1 is not limited, improving assembly workability and facilitating assembly by robot.

[0032] The outer wall barrier 33 of the outer wall member 35 is a fitting portion for the fitting groove 36 of the housing 1, but the fitting groove 36 is not present in the portion covering the intra-wall air passage 18, and instead functions as the outer wall barrier 33 for waterproofing the intra-wall air passage 18. Furthermore, together with the inner wall barrier 34 provided on the inner wall 27, the second labyrinth structure 26 is formed, as in Example 1. The outer wall member 35 is made flexible, so that it bends under the pressure of water from a fountain directed toward the external air vent 21, blocking the external air vent 21 and preventing water from entering. Furthermore, to prevent water from seeping into the ventilation structure due to capillary action between the housing 1 and the outer wall member 35, a drainage channel 54 is provided at the fitting portion between the outer wall barrier 33 and the fitting groove 36, allowing any water that seeps in to flow out to the external air vent 21.

[0033] FIG. 3(c) shows the ventilation structure of Example 2, which has three internal ventilation openings 20. Each internal ventilation opening 20 connects to the internal ventilation passage 18 within the housing wall 7. The internal ventilation passages 18 extend to the center of the ventilation structure, merge, and connect to the external ventilation opening 21. A filter is installed at the central junction to ensure dust and insect protection. By providing three internal ventilation openings 20, the time required to clear lens fogging caused by condensation over a wider area can be reduced. Furthermore, by combining the internal ventilation passages 18 from the three internal ventilation openings 20 in one location at the center of the circular ventilation structure, the outer wall member 35 is made round and has the same shape as a concentric circle. This creates a symmetrical shape in the vertical and horizontal directions, eliminating limitations on the orientation of the outer wall member 35 when assembling it to the housing 1, improving assembly workability.

[0034] In Figure 3(c), a filter locking portion 39 is provided in the center of the outer wall member 35 to prevent the filter from falling off, and a cap locking portion 40 is provided at the tip of the filter locking portion 39.The cap locking portion 40 is fitted into a cap locking hole 41 provided in the inner wall 27 of the intra-wall air passage 18, thereby preventing the outer wall member 35 from falling off. [Example]

[0035] 5 and 6 show a third embodiment of the ventilation structure of the present invention. An internal ventilation port 20 from inside the housing 4 communicates with an internal ventilation channel 18, which is circumferentially arranged around the inside of the circular ventilation structure within the housing wall 7. The internal ventilation channel 18 communicates with an external ventilation port 21, connecting the inside of the housing 4 to the outside of the housing 13. The internal ventilation channel 18 is provided with a first labyrinth structure and a second labyrinth 26. When ventilation air enters the internal ventilation channel 18 from the outside of the housing 13, pressure loss occurs due to the large expansion chamber 25. The internal ventilation channel 18 branches into two directions, and pressure loss is further reduced by the refraction caused by the blocking wall 24 and the expansion chamber 25. The elimination of the filter further reduced costs.

[0036] A cap locking hole 41 is provided in the center where the filter of Example 2 was provided, and the outer wall member 35 is molded from rubber, has a cap locking portion 40 in the center, and is fitted into the cap locking hole 41 provided in the housing. [Example]

[0037] The embodiment in Figure 7 is a diagram of Example 4 of the ventilation structure of the present invention, and is an example for when it is desired to install the ventilation mechanism of the present invention in a location suitable for shortening the time it takes to eliminate condensation, and when there is another component storage section 52 or the like on the outside of the casing of the housing 1, as in section P in Figure 12(a), and a conventional ventilation mechanism or ventilation member cannot be installed.

[0038] The external ventilation port 21 is provided at a location on the outside of the housing 1 where there are no other component storage sections 52, etc., and the internal ventilation port 20 is provided at a location suitable for shortening the time it takes for the ventilation mechanism of the present invention to eliminate condensation, and the external ventilation port 21 and the internal ventilation port 20 are connected by the internal ventilation path 18 in the wall. Grooves that will become the exterior ventilation port 21 and the in-wall ventilation path 18 are formed in advance in the housing 1 during molding, and an exterior wall member is attached to the in-wall ventilation path 18 on the exterior side 13 of the housing to form the exterior ventilation path 21, and an interior wall member 51 equipped with the interior ventilation port 20 is attached from the interior side of the housing 4. The ventilation mechanism of the present invention makes it possible to install the interior ventilation port 20 in an appropriate location to shorten the time it takes to eliminate condensation. [Example]

[0039] 8 is a diagram of Example 5, which is a ventilation member that forms the ventilation structure of the present invention when attached to housing 1, and ventilation member 43 has inner ventilation port 20, outer ventilation port 21, and in-wall ventilation passage 18 that communicates between inner ventilation port 20 and outer ventilation port 21 when attached to housing 1, and is structured so that slide groove 44 of ventilation member 43 is fitted into slide portion 47 provided on the inner periphery of an opening provided in housing 1, and locking portion 45 of ventilation member 43 is fitted and fixed into drop prevention wall 46 provided on housing 1. This type is used when the structure of the casing makes it impossible to mold complex in-wall ventilation passage 18 into housing 1 due to the structure of the mold, when the housing is made of a material such as metal that makes it difficult to form an in-wall ventilation passage, or when the housing is in the design prototype stage. [Example]

[0040] Figure 9 is a diagram of Example 6, in which an internal air vent 20, an internal air passage 18, an internal wall surface 5 of the housing, and an external wall surface 6 of the housing are formed using a mold when molding the housing 1 for the in-vehicle device, a filter 22 is inserted into the internal air passage 18, an external wall member 19 is fixed by ultrasonic welding, and an external air vent 21 is formed.

[0041] Furthermore, instead of filter 22, a breathable membrane was attached to cover the internal ventilation port 20, ensuring dustproofness. Because the breathable membrane is protected by the housing outer wall surface 6, it will not be damaged during installation or maintenance of the housing. This eliminates the need for a complex structure, such as creating a protruding ventilation path on the inside of the housing 4 and attaching a breathable membrane to that side, expanding the range of locations where a breathable structure can be installed. Furthermore, because it is not directly exposed to water, a hydrophobic PTFE breathable membrane was not used, and instead a polyester nonwoven fabric was attached. This resulted in a significant cost reduction and ensured the sustainable production and supply of breathable structures for in-vehicle equipment, as well as the procurement of materials.

[0042] The above-described embodiments are merely examples in all respects, and the present invention should not be construed as being limited by these descriptions. [Industrial Applicability]

[0043] The present invention can be used in a ventilation structure for equipment. [Explanation of symbols]

[0044] 1. Housing 2 Lens cover 3 light source 4 Inside the enclosure 5. Inner wall of the housing 6. Outer wall of the housing 7 Inside the housing wall 8. Body 9. Close Area 10 Protrusion 11 Cap member 12 Waterproof wall 13 Outside the housing 14 Ventilation hole 15 PTFE breathable membrane 16 Adhesive surface 17 Conventional cap ventilation material 18 In-wall ventilation channel 19 Exterior wall components 20 Internal ventilation opening 21 External ventilation opening 22 filters 23 First labyrinth structure 24 Barrier 25 Expansion chamber 26 Second Labyrinth Structure 27 Inner wall 28 Outer wall 29 Right side wall 30 Left side wall 31 Upper wall 32 Lower wall 33 Exterior Wall Barrier 34 Inner Wall Barrier 35 Exterior wall components 36 Engagement groove 37 Rectangular ventilation structure 38 Round ventilation structure 39 Filter retaining part 40 Cap locking part 41 Cap locking hole 42 Water film condensation protrusion 43 Ventilation material 44 Slide groove 45 Locking part 46 Fall prevention wall 47 Slide section 48 Opening 49 Breathable membrane 50 Fountain backflow prevention slope wall 51 Inner wall member 52 Other parts storage area 53 External ventilation wall 54 Drainage Channel

Claims

1. The ventilation structure of the present invention is characterized in that an internal air vent is provided from the internal wall surface of the housing toward the inside of the wall of the housing without penetrating the external wall surface of the housing, an external air vent is provided from the external wall surface of the housing at an appropriate position spaced along the internal wall surface of the housing from the position of the internal air vent toward the inside of the wall of the housing without penetrating the internal wall surface of the housing, and an internal air passage is provided inside the wall of the housing to communicate the internal air vent and the external air vent, thereby communicating the inside of the housing with the outside of the housing.

2. 2. The ventilation structure for an in-vehicle device according to claim 1, wherein a labyrinth structure is formed in the in-wall ventilation passage.

3. 2. The ventilation structure for an in-vehicle device according to claim 1, wherein an outer barrier wall and an inner barrier wall are provided in the in-wall ventilation passage.

4. 2. The ventilation structure for an in-vehicle device according to claim 1, wherein a filter is installed in the air passage within the wall.

5. 2. The ventilation structure for an in-vehicle device according to claim 1, wherein the outer wall member is a flexible member.

6. 2. The ventilation structure for vehicle-mounted equipment according to claim 1, wherein a drainage channel communicating with an external ventilation port is provided between the outer wall barrier and the groove.

7. 2. The ventilation structure for an in-vehicle device according to claim 1, wherein the ventilation mechanism has a water film condensation protrusion on an inner wall of the outer vent opening.

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