Waterproof ventilation structure and pressure sensor

Abstract

A waterproof ventilation structure is used for communicating an inner cavity of a shell to the environment and comprises a dustproof cover fixed to the upper portion of the shell, and the dustproof cover comprises a cover plate located on the upper side of the shell; the edge of the cover plate protrudes downwards to form a circle of enclosure bulkheads, and the enclosure bulkheads comprise a first enclosure bulkhead which downwards abuts against the shell and a second enclosure bulkhead which laterally abuts against the shell from the outside and forms a vertical ventilation channel with the outer wall of the shell; the lower end of the ventilation channel is communicated to the environment through an opening; the buckling surrounding wall is formed by the cover plate protruding downwards and located on the inner side of the surrounding wall, the buckling surrounding wall is buckled to the outer side of a ventilation part formed by the upper portion of the shell protruding upwards, a ventilation hole communicated to an inner cavity of the shell is formed in the ventilation part, and a waterproof ventilation film is arranged at one end of the inner side of the ventilation hole; one end of the outer side of the ventilation hole communicates with the ventilation channel through a ventilation gap reserved between the ventilation hole and the dustproof cover. According to the waterproof ventilation structure, the inner cavity of the electronic device such as the pressure sensor can be reliably communicated with the environment through the vertical ventilation channel of the dustproof cover.

Description

Technical Field

[0001] The present application relates to the technical field of sensors, and particularly to a waterproof ventilation structure and a pressure sensor. Background Art

[0002] For electronic devices such as pressure sensors that need to introduce ambient pressure into the inner cavity, ventilation is generally carried out through a waterproof ventilation membrane provided at the ventilation hole on the housing. In order to prevent dust, it is also necessary to prevent particulate matters such as dust from invading through the gap between the cover plate and the housing. Since these gaps are small, liquids such as rainwater will be adsorbed at the parts where these gaps communicate with the environment under the action of surface tension. When the entire gap is adsorbed with liquid, these liquids will form a certain liquid seal effect, thus causing ventilation failure, and further resulting in a certain deviation between the pressure in the inner cavity and the ambient pressure; for a pressure sensor, an error will occur when the ambient pressure is used as the reference pressure; in addition, due to the small gap, when the pressure changes violently, the pressure in the cavity will also deviate from the ambient pressure briefly. Summary of the Utility Model

[0003] Aiming at the deficiencies of the prior art, the present application provides a waterproof ventilation structure, which can reliably connect the inner cavity of an electronic device such as a pressure sensor to the environment.

[0004] To achieve the above object, the present application provides the following technical solution: A waterproof ventilation structure for connecting the inner cavity of a housing to the environment, which includes a dust-proof cover fixed to the upper part of the housing, and the dust-proof cover includes:

[0005] A cover plate located on the upper side of the housing;

[0006] A surrounding wall formed by protruding downward from the edge of the cover plate, including a first surrounding wall that abuts downward against the housing and a second surrounding wall that abuts against the housing from the outside laterally and forms a vertical ventilation channel between the second surrounding wall and the outer wall of the housing; the lower end of the ventilation channel is connected to the environment through an opening;

[0007] A fastening surrounding wall formed by protruding downward from the cover plate and located inside the surrounding wall, which is fastened to the outside of a ventilation part formed by protruding upward from the upper part of the housing. A ventilation hole communicating with the inner cavity of the housing is provided in the ventilation part, a waterproof ventilation membrane is provided at the inner end of the ventilation hole, and the outer end of the ventilation hole is connected to the ventilation channel through a ventilation gap left between the ventilation hole and the dust-proof cover.

[0008] Preferably, the surrounding wall includes a rear surrounding wall, a left surrounding wall, a front surrounding wall and a right surrounding wall that are sequentially connected end to end in the circumferential direction; the second surrounding wall includes at least a part of the rear surrounding wall.

[0009] Preferably, the rear enclosure wall extends downward to the lower side of the upper end of the housing, and includes a waist plate extending substantially left and right and two leg plates formed by extending substantially forward from the left and right sides of the waist plate respectively. The front ends of the leg plates abut forward against the housing.

[0010] Preferably, the second enclosure wall further includes at least a part of the left enclosure wall and / or the right enclosure wall.

[0011] Preferably, the second enclosure wall further includes the whole of the first side enclosure wall among the two side enclosure walls of the left enclosure wall and the right enclosure wall and at least a part of the second side enclosure wall.

[0012] Preferably, reinforcing ribs are provided on the lower side of the cover plate, and the reinforcing ribs are located between the first side enclosure wall and the buckling enclosure wall.

[0013] Preferably, the upper end of the ventilation hole is recessed downward to form a depression.

[0014] Preferably, the cover plate protrudes downward to form a baffle that shields the upper part of the front side of the ventilation passage.

[0015] Preferably, the rear enclosure wall protrudes forward to form two opposing left and right extending portions, and the left and right ends of the baffle are respectively connected to the two extending portions. The extending portions abut downward against the housing.

[0016] The present utility model also claims to protect a pressure sensor, which includes the above waterproof ventilation structure. Description of the Drawings

[0017] Figure 1 Is a top view of the pressure sensor of the first embodiment;

[0018] Figure 2 Is the sectional view of the pressure sensor of the first embodiment along Figure 1 A-A shown in;

[0019] Figure 3 Is a bottom view of the dust cover of the first embodiment;

[0020] Figure 4 Is a perspective view of the dust cover of the first embodiment;

[0021] Figure 5 Is a perspective view of the dust cover of a variant of the first embodiment;

[0022] Figure 6 Is a top view of the pressure sensor of the second embodiment;

[0023] Figure 7 Is the sectional view of the pressure sensor of the second embodiment along Figure 6 B-B shown in;

[0024] Figure 8 Bottom view of the dust cover of the second embodiment;

[0025] Figure 9 Stereogram of the dust cover of the second embodiment;

[0026] In the figure: 10, sensor main body; 110, pressure introduction channel; 111a, sealing groove; 111, main housing; 112a, sealing flange; 112, upper cover; 113a, seal; 113, pressure interface; 11a, inner cavity; 11, housing; 12, electrical plug-in part; 130, through hole; 131, substrate; 132, pressure sensitive element; 133, frame; 134, first lead; 135, second lead; 13, electronic module assembly; 14, terminal; 15, waterproof and breathable membrane; 161, ventilation hole; 162, depression; 165a, ventilation groove; 165, fastening part; 16, ventilation part; 191, cover plate; 192a, bottom gap; 192c, front side part; 192d, rear side part; 192, fastening enclosure wall; 1930, ventilation channel; 1931, waist plate; 1932, leg plate; 193a, rear enclosure wall; 193b, front enclosure wall; 193c, left enclosure wall; 193d, right enclosure wall; 193e, first part; 193f, second part; 193g, opening; 193h, extension part; 193, enclosure wall; 194, baffle; 195, spacer; 196, reinforcing rib; 19a, cavity; 19, dust cover; 201, cover plate; 202a, bottom gap; 202b, circumferential notch; 202, fastening enclosure wall; 2030, ventilation channel; 2031, waist plate; 2032, leg plate; 203a, rear enclosure wall; 203b, front enclosure wall; 203c, left enclosure wall; 203d, right enclosure wall; 203g, opening; 203, enclosure wall; 204a, end; 204b, side notch; 204, baffle; 205, spacer; 20a, cavity; 20, dust cover. Detailed implementation manners

[0027] 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.

[0028] In the description of the present application, it should be understood that the orientation or positional relationship indicated by the terms "upper", "lower", "inner", "outer", "left", "right", etc. is based on the orientation or positional relationship shown in the drawings, or the orientation or positional relationship in which the product of the present 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 the present application and simplifying the description, rather than indicating or implying that the device or component referred to must have a specific orientation, be constructed and operated in a specific orientation, and therefore should not be construed as a limitation to the present application.

[0029] In addition, the terms "mounted", "connected", and "coupled" 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 directly connected or indirectly connected through an intermediate medium, and it can be the communication inside two components. For those of ordinary skill in the art, the specific meanings of the above terms in the present application can be understood according to specific circumstances.

[0030] It should be further understood that the term "and / or" used in the specification of the present application and the corresponding claims refers to any combination of one or more of the listed items and all possible combinations.

[0031] As Figures 1 to 4 shown, in the first example of the present utility model, the waterproof and breathable structure of this embodiment is used to connect the inner cavity 11a of the housing 11 of the electronic device to the environment. Such an electronic device can be a pressure sensor or other electronic devices that need to communicate with the atmosphere. As Figure 1 、 Figure 2 shown, the pressure sensor 100 of this embodiment may include a sensor body 10 and the above-mentioned waterproof and breathable structure.

[0032] The following only exemplarily describes the sensor body 10. It should be understood that in some other embodiments, the sensor body 10 may be other known structures. The sensor body 10 includes a housing 11. The housing 11 includes a main housing 111 and an upper cover 112 fixedly disposed downward at the upper end of the main housing 111. The main housing 111 and the upper cover 112 enclose the inner cavity 11a of the sensor body 10. Only by way of example, an opening is provided at the upper end of the main housing 111, and a sealing groove 111a is provided at the edge of the opening. The edge of the upper cover 112 protrudes downward to form a sealing flange 112a. The sealing flange 112a is inserted downward into the sealing groove 111a and is fixed and sealed by a sealing glue (not shown) filled in the sealing groove 111a.

[0033] On the front side of the main housing 111, a shell-shaped electrical connector part 12 may be provided. A plurality of terminals 14 are provided on the electrical connector part 12. One end of the terminal 14 is located inside the electrical connector part 12, and the other end of the terminal 14 extends into the inner cavity 11a. At the lower end of the main housing 111, a pressure interface 113 for introducing a pressure medium to be measured is provided, and the inner end of the pressure interface 113 communicates with the inner cavity 11a. The sensor main body 10 further includes an electronic module assembly 13 disposed in the inner cavity 11a. The substrate 131 includes a sealing part fixed to the inner end of the pressure interface 113, and a through hole 130 is provided thereon. The sensor main body 10 further includes a pressure sensitive element 132 fixedly sealed at a side of the through hole 130 away from the pressure introduction channel 110. The pressure sensitive element 132 is electrically connected to a processing circuit (not shown) provided on the corresponding side of the substrate 131 through a first lead 134. The processing circuit is also electrically connected to the inner end of the terminal 14 through a second lead 135. Wherein, a frame 133 may be fixedly provided on a side of the substrate 131 away from the pressure introduction channel 110. The frame 133 surrounds the outside of the pressure sensitive element 132, and a protective material (such as gel) covering the pressure sensitive element 132 and the first lead 134 is filled inside it. A seal 113a may be sleeved outside the pressure interface 113 to seal with a container filled with the pressure medium to be measured.

[0034] The waterproof and breathable structure of this embodiment includes a dust cover 19 fixed to the upper part of the housing 11. The dust cover 19 includes a cover plate 191 located on the upper side of the housing 11, a surrounding wall 193 formed by protruding downward from the edge of the cover plate 191, and a surrounding wall 192 formed by protruding downward from the cover plate 191 and located inside the surrounding wall 193. Among them, the surrounding wall 193 includes a first surrounding wall that abuts downward against the housing 11 and a second surrounding wall that abuts against the housing 11 from the outside and forms a vertical ventilation channel 1930 between the outer wall of the housing 11. The lower end of the ventilation channel 1930 is connected to the environment through an opening 193g. The surrounding wall 192 is buckled outside a ventilation part 16 formed by protruding upward from the upper part of the housing 11. A ventilation hole 161 communicating with the inner cavity 11a of the housing 11 is provided inside the ventilation part 16. A waterproof and breathable membrane 15 is provided at the inner end of the ventilation hole 161. The outer end of the ventilation hole 161 is connected to the ventilation channel 1930 through a ventilation gap left between it and the dust cover 19. Specifically, the lower end of the first surrounding wall abuts downward against the upper end of the upper cover 112 or the upper end of the main housing 111, the lower end of the second surrounding wall extends downward beyond the upper end of the upper cover 112 and the upper end of the main housing 111, and the inner side wall abuts inward against the upper cover 112 or the main housing 111. Among them, the ambient pressure is sequentially connected to the inner cavity 11a through the opening 193g, the ventilation channel 1930, the cavity 19a inside the dust cover 19, the bottom gap 192a, the ventilation groove 165a, the top gap, the ventilation hole 161, and the waterproof and breathable membrane 15. In this way, through the vertical ventilation channel, it is possible to effectively prevent liquid from invading the inner cavity 11a through the ventilation hole 161.

[0035] Among them, the lower end of the cover plate 191 forms a top gap (not marked) through a plurality of pads 195 protruding from its lower end and supporting on the upper end of the ventilation part 16. In addition to the top gap, the ventilation gap may also include a bottom gap 192a reserved between at least a part of the bottom of the surrounding wall 192 and the upper end surface of the upper cover 112. The top gap and the bottom gap 192a can be vertically connected through a vertically extending ventilation groove 165a provided on the outer wall of the buckling part 165.

[0036] Please refer to Figure 3 、 Figure 4 and, the surrounding wall 193 may include a rear surrounding wall 193a, a left surrounding wall 193c, a front surrounding wall 193b, and a right surrounding wall 193d that are sequentially connected end to end in the circumferential direction. The lower end of the rear surrounding wall 193a extends downward to the lower side of the upper end of the housing 11, and it includes a waist plate 1931 that extends substantially left and right and two leg plates 1932 that are respectively formed by extending substantially forward from the left and right sides of the waist plate 1931. The leg plate 1932 is part of the second surrounding wall, and the upper part of its front end abuts forward against the housing 11. In this way, the front-to-back width of the ventilation channel 1930 is the front-to-back width of the leg plate 1932.

[0037] In order to be able to assist in positioning the dust cover 19 in the left - right direction, the second surrounding wall may further include at least a part of the left surrounding wall 193c and / or the right surrounding wall 193d. Specifically, as Figure 3 shown, the inner side of the left surrounding wall 193c abuts against the main housing 111 towards the right, and the second part 193f of the right surrounding wall 193d connected to the rear surrounding wall 193a abuts against the main housing 111 towards the left. The first part 193e of the right surrounding wall 193d and the front surrounding wall 193b serve as the first surrounding wall, most of which abuts against the upper end of the upper cover 112 downward, and a small part abuts against the main housing 111. It should be noted that "abutting" here and in other positions in the specification includes abutting connection. Among them, the buckling surrounding wall 192 can be partially connected to the first part 193e.

[0038] In some other solutions, like the right surrounding wall 193d, the part of the left surrounding wall 193c close to the front side belongs to the first surrounding wall (i.e., abuts against the housing 11 downward), and the part close to the rear side belongs to the second surrounding wall (i.e., abuts against the housing 11 laterally from the outside). Among them, the second surrounding wall can make the gap between it and the housing 11 hidden downward, avoiding liquid being adsorbed in the gap between the two or entering the inner cavity 11a from the gap. In some other solutions, the left surrounding wall 193c and / or the right surrounding wall 193d can also entirely belong to the first surrounding wall, that is, they both abut against the housing 11 downward. Among them, a reinforcing rib 196 can be provided on the lower side of the cover plate 191. The reinforcing rib 196 is located between the first side surrounding wall and the buckling surrounding wall 192.

[0039] In some other solutions, the upper end of the ventilation hole 161 can be recessed downward to form a depression 162, thereby improving the ventilation capacity between the upper end of the ventilation hole 161 and the top gap.

[0040] In each implementation scheme of this embodiment, the cover plate 191 can protrude downward to form a baffle 194 that blocks the upper front part of the ventilation channel 1930. This can prevent the jet flow from entering the inner cavity 11a. Among them, the rear surrounding wall 193a protrudes forward to form two extending parts 193h that face each other left and right, and the left and right ends of the baffle 194 are respectively connected to the two extending parts 193h, and the extending parts 193h abut against the housing 11 downward.

[0041] Please refer to Figure 5 , in a variant implementation scheme of the first embodiment, the lower end of the rear part 192d of the buckling surrounding wall 192 can be shortened upward relative to the lower end of the front part 192d, that is, it has a higher gap than the bottom gap between the front part 192d and the housing 11, thereby improving the ventilation capacity. More particularly, the rear part 192d can be completely cut off at the entire height to form a circumferential notch with a circumferential angle less than half of the circumference (please refer to Figure 8 ).

[0042] As Figures 6 to 9 shown, in the second example of the present utility model, the waterproof and breathable structure of this embodiment is used to connect the inner cavity 11a of the housing 11 of the electronic device to the environment. Such an electronic device can be a pressure sensor or other electronic devices that need to communicate with the atmosphere. As Figure 1 、 Figure 2 shown, the pressure sensor 100 of this embodiment may include a sensor body 10 and the above-mentioned waterproof and breathable structure.

[0043] The following only exemplarily describes the sensor body 10. It should be understood that in some other embodiments, the sensor body 10 may be other known structures. The sensor body 10 includes a housing 11, and the housing 11 includes a main housing 111 and an upper cover 112 fixedly disposed downward at the upper end of the main housing 111. The main housing 111 and the upper cover 112 enclose the inner cavity 11a of the sensor body 10. Only by way of example, an opening is provided at the upper end of the main housing 111, and a sealing groove 111a is provided at the edge of the opening. The edge of the upper cover 112 protrudes downward to form a sealing flange 112a, and the sealing flange 112a is inserted downward into the sealing groove 111a and fixed and sealed by a sealing glue (not shown) filled in the sealing groove 111a.

[0044] A shell-shaped electrical connector part 12 may be provided on the front side of the main housing 111. A plurality of terminals 14 are provided on the electrical connector part 12. One end of the terminal 14 is located inside the electrical connector part 12, and the other end of the terminal 14 extends into the inner cavity 11a. A pressure interface 113 for introducing a pressure medium to be measured is provided at the lower end of the main housing 111, and the inner side end of the pressure interface 113 communicates with the inner cavity 11a. The sensor body 10 further includes an electronic module assembly 13 disposed in the inner cavity 11a. The substrate 131 includes a sealing fixed to the inner side end of the pressure interface 113, and a through hole 130 is provided thereon. The sensor body 10 further includes a pressure sensitive element 132 fixedly sealed to the side of the through hole 130 away from the pressure introduction channel 110. The pressure sensitive element 132 is electrically connected to a processing circuit (not shown) provided on the corresponding side of the substrate 131 through a first lead 134. The processing circuit is also electrically connected to the inner side end of the terminal 14 through a second lead 135. Among them, a frame 133 may also be fixedly provided on the side of the substrate 131 away from the pressure introduction channel 110. The frame 133 surrounds the outside of the pressure sensitive element 132, and a protective material (such as gel) covering the pressure sensitive element 132 and the first lead 134 is filled inside it. A sealing member 113a may be sleeved outside the pressure interface 113 to seal with the container containing the pressure medium to be measured.

[0045] The waterproof and breathable structure of this embodiment includes a dust-proof cover 20 fixed to the upper part of the housing 11. The dust-proof cover 20 includes a cover plate 201 located on the upper side of the housing 11, a surrounding wall 203 formed by protruding downward from the edge of the cover plate 201, and a clamping surrounding wall 202 formed by protruding downward from the cover plate 201 and located inside the surrounding wall 203. Among them, the surrounding wall 203 includes a first surrounding wall that abuts downward against the housing 11 and a second surrounding wall that abuts against the housing 11 from the outside and forms a vertical ventilation channel 2030 with the outer wall of the housing 11. The lower end of the ventilation channel 2030 is connected to the environment through an opening 203g. The clamping surrounding wall 202 is clamped outside a ventilation part 16 formed by protruding upward from the upper part of the housing 11. A ventilation hole 161 communicating with the inner cavity 11a of the housing 11 is provided inside the ventilation part 16. A waterproof and breathable membrane 15 is provided at the inner end of the ventilation hole 161. The outer end of the ventilation hole 161 is connected to the ventilation channel 2030 through a ventilation gap left between it and the dust-proof cover 20. Specifically, the lower end of the first surrounding wall abuts downward against the upper end of the upper cover 112 or the upper end of the main housing 111, the lower end of the second surrounding wall extends downward beyond the upper end of the upper cover 112 and the upper end of the main housing 111, and the inner side wall abuts inward against the upper cover 112 or the main housing 111. Among them, the ambient pressure is sequentially connected to the inner cavity 11a through the opening 203g, the ventilation channel 2030, the cavity 20a inside the dust-proof cover 20, the bottom gap 202a, the ventilation groove 165a, the top gap, the ventilation hole 161, and the waterproof and breathable membrane 15. In this way, through the vertical ventilation channel, it is possible to effectively prevent liquid from invading the inner cavity 11a through the ventilation hole 161.

[0046] Among them, the lower end of the cover plate 201 forms a top gap (not marked) through a plurality of pads 205 protruding from its lower end and supporting on the upper end of the ventilation part 16. In addition to the top gap, the ventilation gap may also include a bottom gap 202a reserved between at least a part of the bottom of the clamping surrounding wall 202 and the upper end surface of the upper cover 112. The top gap and the bottom gap 202a can be vertically connected through a vertically extending ventilation groove 165a provided on the outer wall of the clamping part 165.

[0047] Please refer to Figure 8 、 Figure 9, the surrounding wall 203 may include a rear surrounding wall 203a, a left surrounding wall 203c, a front surrounding wall 203b, and a right surrounding wall 203d that are sequentially connected end to end in a circumferential manner. The lower end of the rear surrounding wall 203a extends downward to the lower side of the upper end of the housing 11, and it only includes a waist plate 2031 that extends substantially left and right, and two leg plates 2032 that are formed by extending substantially forward from the left and right sides of the waist plate 2031 respectively. The leg plate 2032, as a part of the second surrounding wall, has its upper part in front of the front end pressing forward against the housing 11. In this way, the front-to-back width of the ventilation passage 2030 is the front-to-back width of the leg plate 2032. The left surrounding wall 203c and the right surrounding wall 203d may all belong to the first surrounding wall, that is, they both press downward against the housing 11.

[0048] In some other solutions, the upper end of the ventilation hole 161 may be recessed downward to form a depression 162, thereby improving the ventilation ability between the upper end of the ventilation hole 161 and the top gap.

[0049] In each implementation of this embodiment, the cover plate 201 may protrude downward to form a baffle 204 that shields the upper part of the front side of the ventilation passage 2030. This can prevent the jet from entering the inner cavity 11a. Among them, there is a side gap 204b left between each of the two ends of the baffle 204 and the left surrounding wall 203c and the right surrounding wall 203d respectively. In some other solutions, the side gap 204b may be provided only at one of the left and right ends of the baffle 204. Preferably, the rear side of the buckling surrounding wall 202 is provided with a circumferential gap 202b with a circumferential angle less than half of the circumference. Preferably, the left and right ends of the side gap 204b respectively cross the left and right end parts 204a of the baffle 204 toward the left and right inner sides correspondingly.

[0050] In this embodiment, the buckling surrounding wall 202 may extend integrally with the front surrounding wall 203b inside the front surrounding wall 203b, or the front surrounding wall 203b directly replaces the buckling surrounding wall 202 and buckles on the outside of the ventilation part 16.

[0051] It should be noted that in each implementation of this embodiment, due to the existence of the circumferential gap 202b, either or both of the ventilation groove 165a and the bottom gap between the rear part of the buckling surrounding wall 202 and the housing 11 may be omitted. At this time, the top gap is directly connected to the cavity 20a inside the dust cover 20 through the circumferential gap 202b, and thus connected to the ventilation passage 2030; in addition, the bottom gap 202a may not be reserved between the lower end of the front part of the buckling surrounding wall 202 and the housing 11 (such as Figure 8As shown, the lower end of the buckling enclosure wall 202 can be flush with the lower end of the front enclosure wall 203b). The lower end of the front side portion of the buckling enclosure wall 202 and / or the front enclosure wall 203b can be directly sealed with the housing 11 through a sealant (not shown). The portions of the left enclosure wall 203c and the right enclosure wall 203d that are located on the upper cover 112 can also be sealed with the upper end surface of the upper cover 112 through a sealant in the same manner.

[0052] The scope of the present disclosure is not limited by the detailed description, but is defined 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 ventilation structure, used for connecting the inner cavity (11a) of a housing (11) to the environment, characterized in that: It comprises a dust cover (19) fixed to the upper part of the housing (11), and the dust cover (19) comprises: A cover plate (191) located on the upper side of the housing (11); A circle of surrounding walls (193) formed by the edge of the cover plate (191) protruding downwards comprises a first surrounding wall approaching the shell (11) downwards and a second surrounding wall approaching the shell (11) from the outside and forming a vertical ventilation channel (1930) with the outer wall of the shell (11); the lower end of the ventilation channel (1930) is connected to the environment through an opening (193g); and a snap-fitting surrounding wall (192) formed by the cover plate (191) protruding downward and located on the inner side of the surrounding wall (193), which is snap-fitted to the outer side of a vent (16) formed by the upper part of the shell (11) protruding upward, wherein the vent (16) is provided with a vent hole (161) connected to the inner cavity (11a) of the shell (11), and a waterproof ventilation membrane (15) is provided at one end of the inner side of the vent hole (161), and the outer end of the vent hole (161) is connected to the ventilation channel (1930) through a ventilation gap left between the vent hole (161) and the dust cover (19).

2. The waterproof ventilation structure according to claim 1, characterized in that: The surrounding wall (193) includes a rear surrounding wall (193a), a left surrounding wall (193c), a front surrounding wall (193b) and a right surrounding wall (193d) which are connected end to end in the circumferential direction; the second surrounding wall includes at least a portion of the rear surrounding wall (193a).

3. The waterproof ventilation structure according to claim 2, characterized in that: The rear surrounding wall (193a) extends downward to the lower side of the upper end of the shell (11), and includes a waist plate (1931) extending substantially left and right, and two leg plates (1932) formed by the left and right sides of the waist plate (1931) respectively extending substantially forward, and the front end of the leg plate (1932) is forwardly close to the shell (11).

4. The waterproof ventilation structure according to claim 2, characterized in that: The second surrounding wall also includes at least a portion of the left surrounding wall (193c) and / or the right surrounding wall (193d).

5. The waterproof ventilation structure according to claim 2, characterized in that: The second surrounding wall also includes the entire first side surrounding wall and at least a portion of the second side surrounding wall of the left side surrounding wall (193c) and the right side surrounding wall (193d).

6. The waterproof ventilation structure according to claim 5, characterized in that: A reinforcing rib (196) is provided on the lower side of the cover plate (191), and the reinforcing rib (196) is located between the first side surrounding wall and the buckled surrounding wall (192).

7. The waterproof ventilation structure according to claim 2, characterized in that: The upper end of the vent hole (161) is concave downward to form a depression (162).

8. The waterproof ventilation structure according to any one of claims 1 to 7, characterized in that: The cover plate (191) protrudes downward to form a baffle plate (194) that blocks the upper front portion of the ventilation channel (1930).

9. The waterproof ventilation structure according to claim 3, characterized in that: The rear surrounding wall (193a) protrudes forward to form two extension parts (193h) facing each other on the left and right. The left and right ends of the baffle (194) are respectively connected to the two extension parts (193h). The extension parts (193h) are downward and close to the shell (11).

10. A pressure sensor, characterized in that: The waterproof ventilation structure comprises the waterproof ventilation structure as claimed in any one of claims 1 to 9.

Images