Waterproof breathable structure and device

Abstract

The utility model provides a waterproof breathable structure and device, and the structure comprises a housing which is internally provided with a housing inner cavity; the connecting seat is arranged at the upper part of the shell, and a vent hole communicated with the inner cavity of the shell is formed in the connecting seat; the dustproof cover covers the upper end of the connecting base, a dustproof gap is formed between the dustproof cover and the lower end face of the connecting base, a ventilation channel is defined between the dustproof cover and the connecting base, and the ventilation hole is communicated with the environment through the ventilation channel and the dustproof gap; the waterproof breathable film is sealed at one end of the inner side of the vent hole; and the lower end surface of the connecting seat and / or the surface of the shell opposite to the lower end surface of the connecting seat are / is coated with a hydrophobic film. The waterproof and breathable structure and device can prevent liquid from entering the dustproof cover in a large amount or multiple times and blocking the waterproof and breathable film.

Description

[0001] This application is a divisional application. The application number of the original application is 202322338513.0, the filing date of the original application is August 29, 2023, and the title of the original application is "A Waterproof and Breathable Structure and Device". The entire content of the original application is incorporated herein by reference. Technical Field

[0002] This application relates to the technical field of sensors, and particularly to a waterproof and breathable structure and device. Background Art

[0003] A pressure sensor is a sensor used to measure the pressure of an environment or a medium. Currently, pressure measurement is mostly carried out by the components forming a measurement bridge on an elastic membrane, and the resistance value changes correspondingly when stress is applied, thereby outputting a current or voltage signal. MEMS (Micro-Electro-Mechanical System) pressure sensors have been widely used due to advantages such as low cost and easy miniaturization. Among them, the middle part of the silicon core is set as a membrane-like shape, and the pressure applied to both sides of the silicon membrane causes the resistance value of the doped resistors on the silicon membrane to change. The current or voltage signal output by the measurement circuit composed of several resistors can be further processed by a conditioning circuit and then output the measurement result externally. When there is a vacuum chamber on one side of the diaphragm inside the silicon chip, the measured pressure is the pressure of the other side relative to the vacuum, that is, the absolute pressure; when atmospheric pressure is introduced on one side of the diaphragm, the measured pressure is the pressure relative to the atmosphere, that is, the gauge pressure; when different pressures are introduced on both sides of the diaphragm, the measured pressure is the difference between the two pressures, that is, the differential pressure. In some other pressure sensors, a temperature-sensitive element can also be integrated to measure the pressure and temperature of the medium simultaneously.

[0004] For a gauge pressure sensor, it needs to be connected to the atmosphere through a ventilation structure to obtain the atmospheric reference pressure. In a relatively harsh working environment such as particulate dust, a dust-proof structure also needs to be set up. CN111289167A discloses a pressure sensor which isolates the moisture in the environment from the main cavity by setting a waterproof breathable membrane inside the dust-proof connection seat, and covers a dust-proof cover outside the dust-proof connection seat. The atmospheric pressure is communicated to the waterproof breathable membrane through the microchannel between the dust-proof cover and the dust-proof connection seat. The microchannel therein can prevent particles from entering. When this waterproof breathable structure is used on a vehicle, the surface of the cover will often be contaminated with liquid, and these liquids are sucked into the capillary channel to produce liquid seal; on the other hand, when the temperature in the cavity of the sensor changes, the siphoned liquid will also be sucked in or discharged inward to a certain extent, but when more liquid is sucked in, the liquid will be adsorbed on the surface of the breathable membrane. Due to the evaporation of the liquid itself and the heat dissipation of the sensor during operation, these liquids will not be retained for a long time. However, there are inorganic salt additives such as sodium phosphate and sodium nitrate in windshield washer fluid and antifreeze coolant. After these liquids evaporate, some inorganic salts will remain on the breathable membrane. After repeating such a process many times, the breathable membrane will be partially or even completely blocked by inorganic salt particles, causing the reference pressure to deviate from the true atmospheric pressure in the environment, thereby causing measurement errors. Summary of the Utility Model

[0005] In view of the deficiencies of the prior art, the present application provides a waterproof breathable structure to solve at least one of the above-mentioned disadvantages, and the waterproof breathable structure is used to avoid blocking the waterproof breathable membrane due to the sucked-in liquid.

[0006] The waterproof breathable structure provided by the present utility model includes:

[0007] A housing, which forms a housing cavity therein;

[0008] A connection seat provided on the upper part of the housing, which is provided with a ventilation hole communicating with the housing cavity;

[0009] A dust-proof cover covering the upper end of the connection seat, which has a dust-proof gap between its lower end surface and the lower end surface of the connection seat, and forms a breathable channel with the connection seat. The ventilation hole communicates with the environment through the breathable channel and the dust-proof gap;

[0010] And a waterproof breathable membrane sealed at the inner end of the ventilation hole;

[0011] Wherein, the lower end surface of the connection seat and / or the surface of the housing at a position facing the lower end surface of the connection seat is covered with a hydrophobic membrane.

[0012] Preferably, the upper surface of the housing is lifted upward to form a lifting seat, and the connection seat is connected to the upper end surface of the lifting seat; the dust-proof gap is formed between the lower end surface of the dust-proof cover and the upper end surface.

[0013] Preferably, the dust cover includes a plate portion and a wall portion protruding from the plate portion toward the housing side; at least one ventilation groove is circumferentially and spacedly provided on the outer side of the connecting seat; the ventilation channel includes a horizontal channel formed between the inner wall of the plate portion and the top surface of the connecting seat and a vertical channel surrounded by the inner wall of the wall portion and the ventilation groove; the upper end of the vertical channel communicates with the horizontal channel, and the lower end communicates with the dust prevention gap.

[0014] Preferably, a first expansion cavity is formed by inwards recessing at the inner edge of the lower end of the wall portion.

[0015] Preferably, a third expansion cavity is formed by inwards recessing at the connection between the plate portion and the wall portion.

[0016] Preferably, a plurality of protruding stoppers are formed by outwards protruding on the inner side of the plate portion, and the protruding stoppers abut against the top end of the connecting seat.

[0017] Preferably, the connecting seat includes a cylindrical portion extending vertically and a first positioning portion formed by outwards protruding from the upper end of the cylindrical portion; a second positioning portion for snap-connecting with the first positioning portion is correspondingly provided at the lower end of the dust cover, and the ventilation hole is arranged inside the cylindrical portion.

[0018] Preferably, a circular groove is formed by inwards recessing between the bottom of the cylindrical portion and the first positioning portion, and the inner end of the inner side of the circular groove extends radially inwards to the inner surface of the ventilation groove.

[0019] Preferably, a second expansion cavity is formed by inwards recessing at the outer edge of the top end of the cylindrical portion.

[0020] The present utility model also claims protection for a device including the waterproof and breathable structure. Description of the Drawings

[0021] Figure 1 It is a schematic structural view of the waterproof and breathable structure according to the first embodiment of the present utility model;

[0022] Figure 2 It is a schematic structural view of the waterproof and breathable structure according to the second embodiment of the present utility model;

[0023] Figure 3 It is a schematic structural view of the waterproof and breathable structure according to the third embodiment of the present utility model;

[0024] Figure 4 It is a schematic structural view of the waterproof and breathable structure according to the third embodiment of the present utility model when the liquid at the storage upper limit is inhaled into the dust cover;

[0025] Figure 5 It is a schematic structural view of the waterproof and breathable structure according to the fourth embodiment of the present utility model when the liquid at the storage upper limit is inhaled into the dust cover;

[0026] Description of reference numerals: 10, inner cavity of the housing; 11, upper cover of the housing; 120, upper end surface; 12, lifting seat; 13a, dust-proof gap; 13, mounting surface; 19, upper surface; 1s, cavity; 1, housing; 20, ventilation hole; 21a, annular groove; 21, cylindrical part; 22, first positioning part; 23a, second expansion cavity; 23, chamfered part; 24, gradually expanding part; 25, top end; 2, connecting seat; 30a, horizontal channel; 30b, vertical channel; 30c, third expansion cavity; 30, plate part; 31, second positioning part; 32, protruding stop part; 33a, first expansion cavity; 33, concave part; 34, lower end surface; 35, wall part; 3, dust-proof cover; 4, waterproof and breathable membrane; 35a, first conical surface; 12a, second conical surface; Detailed implementation mode

[0027] The following definitions of terms shall apply throughout the application document:

[0028] The orientation or positional relationship indicated by the terms "upper", "lower", "left", "right", "front", "rear", "inner", "outer", "far", "near" and their combinations, etc. is based on the orientation or positional relationship shown in the drawings, or the orientation or positional relationship in which the product of this application is usually placed during use, or the orientation or positional relationship commonly understood by those skilled in the art. It is only for the convenience of describing this application and simplifying the description, rather than indicating or implying that the device or element referred to must have a specific orientation, be constructed, operated and used in a specific orientation, and therefore should not be construed as a limitation to this application; and, when the terms "horizontal" and "horizontal plane" are not limited by their special relationship with the direction of the earth's gravity, they refer to a direction or plane that is roughly perpendicular to the "upper" and "lower", and when "longitudinal" and "transverse" are not limited by the plane they are in, they refer to two orthogonal directions on the "horizontal plane";

[0029] The term "and / or" means any combination of one or more of the listed items and all possible combinations;

[0030] The terms "mount", "connect", and "couple" should be understood in a broad sense. For example, it can be a fixed connection, a detachable connection, or an integral connection; it can be a mechanical connection or an electrical connection; it can be a direct connection or an indirect connection through an intermediate medium, and it can be the communication inside two elements. For those of ordinary skill in the art, the specific meanings of the above terms in this application can be understood according to specific circumstances;

[0031] The term "comprising" means including but not limited to, and should be interpreted in the way commonly used in the patent context;

[0032] When terms such as "about" or "approximately" are used in conjunction with a number, they may mean the specific number, or alternatively, a range close to the specific number as understood by those skilled in the art; and if the specification states that a component or feature "can", "may", "might", "possibly", "be able to", "is capable of", "preferably", "more preferably", "best", "particularly", "generally", "optionally", "for example", "frequently", "specifically" (or other such words) is included or has a certain property, then the specific component or feature is not necessarily included or has the property, but is optional, that is, such a component or feature may optionally be included in some embodiments, or may be excluded;

[0033] Phrases such as "in one embodiment", "according to one embodiment", "in other embodiments", "in additional embodiments", etc. generally mean that the specific feature, structure or property following such a phrase may be included in at least one embodiment of the present utility model, and may be included in more than one embodiment of the present utility model (importantly, such phrases do not necessarily refer to the same embodiment); if the specification describes something as "exemplary" or "an example", it should be understood to mean a non-exclusive example;

[0034] The technical solutions of the present application will be clearly and completely described below with reference to the accompanying drawings. The following embodiments are exemplary and are only used to explain the present application, and cannot be construed as a limitation of the present application. In the following description, the same reference numerals are used to represent the same or equivalent elements, and repeated descriptions are omitted.

[0035] As Figure 1 shown, the first embodiment of the present application provides a waterproof and breathable structure, which includes a housing 1, a connecting seat 2, a dust cover 3, and a waterproof and breathable membrane 4. Among them, a housing cavity 10 is formed inside the housing 1. The connecting seat 2 is arranged on the upper part of the housing 1, and an air vent 20 communicating with the housing cavity 10 is provided therein. The dust cover 3 covers the upper end of the connecting seat 2, and a dust-proof gap 13a is provided between its lower end surface and the lower end surface of the connecting seat 2. A breathable channel is formed between the dust cover 3 and the connecting seat 2. The air vent 20 communicates with the environment through the breathable channel and the dust-proof gap 13a. The waterproof and breathable membrane 4 is sealed at one inner end of the air vent 20. A part of the upper surface 19 of the housing 1 is lifted upward to form a lifting seat 12. The connecting seat 2 is connected to the upper end surface 120 of the lifting seat 12. A dust-proof gap 13a is formed between the lower end surface 34 of the dust cover 3 and the upper end surface 120. Among them, the housing 1 may be composed of a main housing (not shown) and a housing upper cover 11.

[0036] The waterproof and breathable structure of this embodiment can effectively protect the film-like liquid remaining on the upper surface of the housing upper cover 11. That is, when the thickness of the film-like liquid is less than the lifting height of the lifting seat 12 (the height difference between the upper end surface 120 and the upper surface 19), it will not enter the dust-proof gap 13a. Since the aqueous liquids such as antifreeze and windshield washer fluid below the lower end surface 34 will adhere to the lower end surface 34 under vibration and form a wall adhesion due to the surface tension effect (the dust-proof cover 3 is usually hydrophilic, that is, the contact angle with water is less than 90°), that is, although the overall height of the liquid on the upper surface 19 is lower than the lower end surface 34, it will not break away from the lower end surface 34 due to the surface tension near the lower end surface 34, and liquid sealing will occur. This will cause part of the liquid to be sucked into the dust-proof cover 3 when the temperature inside the housing upper cover 11 drops, and adhere to the surface of the waterproof and breathable membrane 4 under vibration or when the height exceeds the top of the connecting seat 2; and be sucked above the mating gap under the siphon effect of the mating gap between the connecting seat 2 and the dust-proof cover 3. To solve this defect, in some other embodiments, a hydrophobic film can be sprayed on at least one of the lower end surface 34 and the upper end surface 120. The hydrophobic film will not cause the aqueous liquid to form a wall adhesion and capillary siphon, but on the contrary, it will prevent the aqueous liquid from adhering to the lower end surface 34 and rising along the mating gap. Preferably, the lower cross-sectional area of the ventilation hole 20 gradually expands to form a tapered portion 24, which can correspondingly increase the ventilation area of the waterproof and breathable membrane 4 and relatively reduce the degree of blockage.

[0037] In some other solutions, a hydrophobic film can also be coated between the outer wall of the connecting seat 2 and the inner wall of the dust-proof cover 3 (that is, on the inner wall of the cavity communicating with the ventilation channel). The hydrophobic film can be formed on the above surfaces by common methods such as spraying a hydrophobic liquid or pasting a solid hydrophobic film.

[0038] Among them, the dust-proof cover 3 can include a plate portion 30 and a wall portion 35 protruding from the plate portion 30 toward the housing upper cover 11. At least one circumferentially spaced ventilation groove (not marked) is provided on the outside of the connecting seat 2. The ventilation channel includes a horizontal channel 30a formed between the inner wall of the plate portion 30 and the top surface 25 of the connecting seat 2 and a vertical channel 30b formed by the inner wall of the wall portion 35 and the ventilation groove. The upper end of the vertical channel 30b communicates with the horizontal channel 30a. The lower end communicates with the dust-proof gap 13a. A plurality of protruding blocking portions 32 protrude outward from the inner side of the plate portion 30, and the protruding blocking portions 32 abut against the top 25 of the connecting seat 2, so that a horizontal channel 30a can be formed between the inner wall of the plate portion 30 and the top surface 25 of the connecting seat 2.

[0039] The connecting base 2 includes a cylindrical portion 21 extending vertically and a first positioning portion 22 protruding outward from the upper end of the cylindrical portion 21. A second positioning portion 31 is correspondingly provided at the lower end of the dust cover 3 for snap - connection with the first positioning portion 22. The ventilation hole 20 is arranged inside the cylindrical portion 21. An installation surface 13 is recessed on the inner wall of the housing upper cover 11. The edge of the waterproof and breathable membrane 4 is adhered to the installation surface 13.

[0040] To further prevent the liquid entering the dust cover 3 from being sucked into the ventilation hole 20 due to the pressure drop in the inner cavity 10 of the housing, the volume of the cavity 1s communicating with the breathable channel and located outside the top of the connecting base 2 can be relatively enlarged. For example, as Figure 2 shown in the second embodiment, the inner edge at the lower end of the wall portion 35 can be recessed inward to form an inner recess 33, and a first enlarged cavity 33a is formed between it and the upper surface 120; the outer edge at the top of the cylindrical portion 21 can form a chamfered portion 23, and a second enlarged cavity 23a is formed between the chamfered portion 23 and the dust cover 3; as Figure 3 、 Figure 4 shown in the third embodiment, the connection between the plate portion 30 and the wall portion 35 can also be recessed inward to form a third enlarged cavity 30c. In addition, a circular groove 21a is recessed inward between the bottom of the cylindrical portion 21 and the first positioning portion 22, and the inner end of the circular groove 21a extends radially inward to the inner surface of the ventilation groove. In this way, when the pressure change in the inner cavity 10 of the housing is not too large, as long as the liquid entering the dust cover 3 does not exceed a certain volume, the liquid can be stored in the cavity without being sucked into the ventilation hole 20, thereby ensuring temporary breathability and preventing or reducing the blockage of the waterproof and breathable membrane caused by non - volatile particles in the liquid.

[0041] To prevent muddy water from entering the dust - proof gap 13a, it is preferably to form a flared opening (not marked, refer to Figure 5 shown in the fourth embodiment) that opens upward and downward on the outside of the dust - proof gap 13a. This can avoid the adsorption effect of the narrow space of the dust - proof gap 13a on the muddy water and ultimately prevent the muddy water from blocking the dust - proof gap. Preferably, the upper surface 19 of the housing 1 can be lifted upward to form a lifting seat 12. The connecting base 2 is connected to the upper surface 120 of the lifting seat 12. The above - mentioned dust - proof gap 13a is formed between the lower surface 34 of the dust cover 3 and the upper surface 120. Among them, the upper surface 120 of the lifting seat 12 and the upper surface 19 of the housing 1 can be connected by a first conical surface 12a, and the first conical surface 12a forms the lower edge of the flared opening; additionally or alternatively, a second conical surface 35a is formed on the lower part of the outer surface of the wall portion 35, and the second conical surface 35a forms the lower edge of the flared opening. Similarly, the surface of the flared opening can be covered with a hydrophobic membrane.

[0042] The above - mentioned waterproof and breathable structure is very suitable for pressure sensors, especially absolute - pressure sensors, and does not exclude its applicability to other sensors or devices that require waterproof and breathable functions.

[0043] The scope of the present disclosure is not limited by the detailed description, but rather by the claims and their equivalents, and all variations within the scope of the claims and their equivalents are construed as being included in the present disclosure.

Claims

1. A waterproof and breathable structure, characterized in that, Comprising: A housing (1) within which a housing inner cavity (10) is formed; A connecting seat (2) provided at the upper part of the housing (1), having a ventilation hole (20) provided therein that communicates with the housing inner cavity (10); A dust-proof cover (3) covering the upper end of the connecting seat (2), having a dust-proof gap (13a) between its lower end surface and the lower end surface of the connecting seat (2), and surrounding a ventilation channel with the connecting seat (2), and the ventilation hole (20) communicates with the environment through the ventilation channel and the dust-proof gap (13a); And a waterproof and breathable film (4) sealed at the inner end of the ventilation hole (20); Wherein, a hydrophobic film is covered on the lower end surface (34) of the connecting seat (2) and / or the surface of the housing (1) at a position facing the lower end surface (34) of the connecting seat (2).

2. The waterproof and breathable structure according to claim 1, characterized in that, The upper surface (19) of the housing (1) is lifted upward to form a lifting seat (12), and the connecting seat (2) is connected to the upper end surface (120) of the lifting seat (12); the dust-proof gap (13a) is formed between the lower end surface (34) of the dust-proof cover (3) and the upper end surface (120).

3. The waterproof and breathable structure according to claim 1, characterized in that, The dust-proof cover (3) includes a plate portion (30) and a wall portion (35) protruding from the plate portion (30) toward the housing (1); at least one ventilation groove is circumferentially spaced and provided on the outer side of the connecting seat (2); the ventilation channel includes a horizontal channel (30a) formed between the inner wall of the plate portion (30) and the surface of the top end (25) of the connecting seat (2) and a vertical channel (30b) formed by the inner wall of the wall portion (35) and the ventilation groove; the upper end of the vertical channel (30b) communicates with the horizontal channel (30a), and the lower end communicates with the dust-proof gap (13a).

4. The waterproof and breathable structure according to claim 3, characterized in that, An inward depression is formed at the inner edge of the lower end of the wall portion (35) to form a first expansion cavity (33a).

5. The waterproof and breathable structure according to claim 3, characterized in that, An inward depression is formed at the connection between the plate portion (30) and the wall portion (35) to form a third expansion cavity (30c).

6. The waterproof and breathable structure according to claim 3, characterized in that, A plurality of protruding stop portions (32) protrude outward from the inner side of the plate portion (30) and the protruding stop portions (32) abut against the top end (25) of the connecting seat (2).

7. The waterproof and breathable structure according to claim 1, characterized in that, The connecting seat (2) includes a cylindrical portion (21) extending vertically and a first positioning portion (22) protruding outward from the upper end of the cylindrical portion (21); a second positioning portion (31) for snap-connecting with the first positioning portion (22) is correspondingly provided at the lower end of the dust-proof cover (3), and the ventilation hole (20) is provided in the cylindrical portion (21).

8. The waterproof and breathable structure according to claim 7, characterized in that, An annular groove (21a) is formed by inward depression between the bottom of the cylindrical portion (21) and the first positioning portion (22), and the inner end of the annular groove (21a) extends radially inward to the inner surface of the ventilation groove.

9. The waterproof and breathable structure according to claim 7, characterized in that, An inward depression is formed at the outer edge of the top end of the cylindrical portion (21) to form a second expansion cavity (23a).

10. A device, characterized in that, Comprising the waterproof and breathable structure according to any one of claims 1 to 9.

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