CN219777422U - Detection device and range hood - Google Patents

Abstract

The utility model discloses a detection device and a range hood provided with the detection device, wherein the detection device comprises a shell and a circuit board arranged in a containing cavity of the shell, the circuit board is provided with a transmitter and a receiver, the shell is provided with a first through hole and a second through hole which are communicated with the containing cavity, the transmitter can emit emergent light to the outside of the shell through the first through hole, and the receiver can receive the emergent light to act on retroreflected light formed after detected smoke or water vapor through the second through hole; wherein the first through hole and the second through hole are arranged such that an overlapping portion is formed between a light field of outgoing light formed by the emitter through the first through hole and a sensing range formed by the receiver through the second through hole. The utility model also discloses a range hood, which comprises a hood main body and the detection device. The detection device has smaller volume, and even if the detection device is arranged in the exhaust flue of the range hood, the detection device has smaller blocking influence on the exhaust flue and does not obstruct the normal discharge of smoke or water vapor.

Description

Detection device and range hood

Technical Field

The utility model relates to the technical field of smoke detection, in particular to a detection device and a range hood.

Background

The smoke detection technology is a measure means for the smoke concentration of the current environment and is commonly used in range hood equipment. The detection device generally includes a base and a detection light emitting structure and a detection light receiving structure that are independently provided on the base. The detection light emitted by the detection light emitting structure is reflected and refracted after meeting the smoke, and the reflected light and the refracted light of the detection light are captured by the detection light receiving structure, so that the concentration condition of the smoke is judged.

In the related art, the detecting device is disposed in the flue of the range hood, when the detecting device is disposed as a base and a structure of a detecting light emitting structure and a detecting light receiving structure independently disposed on the base. The whole detection device is large in size, and the area of the flue of the range hood occupied by the detection device is also large, so that the air quantity of the range hood can be reduced.

Disclosure of Invention

The utility model provides a detection device and a range hood with the detection device. The detection device has smaller volume, so that the blocking influence on the smoke exhaust channel of the range hood is smaller, and the normal emission of smoke or water vapor is not blocked.

In a first aspect, the present utility model provides a detection device comprising a housing, a circuit board, a transmitter, and a receiver. The shell is provided with a containing cavity, and a first through hole and a second through hole which are communicated with the containing cavity are formed in the shell. The circuit board sets up in holding the intracavity, and transmitter and receiver all set up on the circuit board. The emitter can emit emergent light to the outside of the shell through the first through hole, and the receiver can receive the retroreflected light formed after the emergent light acts on the detected smoke or water vapor through the second through hole; wherein the first through hole and the second through hole are arranged such that an overlapping portion is formed between a light field of outgoing light formed by the emitter through the first through hole and a sensing range formed by the receiver through the second through hole.

In some embodiments, the casing is further provided with an electromagnetic shielding structure surrounding the outer side of the circuit board, and the electromagnetic shielding structure is used for preventing external electromagnetic waves from interfering with the circuit board, the transmitter and the receiver.

In some embodiments, the electromagnetic shielding structure is an electromagnetic shielding film, and the electromagnetic shielding film is attached to the inner wall and/or the outer wall surface of the shell; or the electromagnetic shielding structure is a metal coating, and the metal coating is coated on the inner wall and/or the outer wall surface of the shell; or the electromagnetic shielding structure is metal shielding powder particles which are embedded in the wall body of the shell.

In some embodiments, the plurality of receivers are arranged around the emitter, the plurality of second through holes are arranged around the first through hole, the plurality of second through holes are in one-to-one correspondence with the plurality of receivers, and the receivers can receive the retroreflected light formed after the outgoing light acts on the detected smoke or water vapor through the corresponding second through holes.

In some embodiments, the housing includes an outer shell having a mounting slot and an inner shell having a second mounting slot and a cover plate for closing the first and second mounting slots. The cover plate is connected to the same side of the outer shell and the inner shell. The first through hole comprises a first sub through hole and a second sub through hole which are communicated with each other, the first sub through hole is formed in the outer shell, and the second sub through hole is formed in the inner shell. The second through hole comprises a third sub through hole and a fourth sub through hole which are communicated with each other, the third sub through hole is formed in the outer shell, and the fourth sub through hole is formed in the inner shell.

In some embodiments, the emitter comprises a light emitting part and a first connecting part which are connected with each other, the first connecting part is connected to the circuit board, the light emitting part penetrates through the first sub through hole and partially stretches into the second sub through hole, the receiver comprises a photosensitive part and a second connecting part which are connected with each other, the second connecting part is connected to the circuit board, and the photosensitive part penetrates through the third sub through hole and partially stretches into the fourth sub through hole; the optical domain that the transmitter is capable of forming and the detection area of the receiver at least partially overlap in a plane perpendicular to the axis of the first sub-via.

In some embodiments, the first sub-via includes a first light-in end relatively close to the emitter and a first light-out end relatively far from the emitter, the first light-in end having a smaller aperture than the first light-out end;

the third sub-through hole comprises a second light inlet end relatively far away from the receiver and a second light outlet end relatively close to the receiver, and the aperture of the second light inlet end is larger than that of the second light outlet end.

In some embodiments, the aperture of the first sub-via increases gradually in a direction away from the second sub-via, or the first sub-via includes a first portion relatively close to the second sub-via and a second portion relatively far from the second sub-via, the aperture of the second portion increasing gradually in a direction away from the second sub-via, the aperture of the first portion being equal to the minimum aperture of the second portion;

the aperture of the third sub-through hole gradually increases in a direction away from the fourth sub-through hole, and the axis of the first sub-through hole and the axis of the third sub-through hole are parallel to each other.

In some embodiments, the emitter comprises a light emitting part and a first connecting part which are connected with each other, the first connecting part is connected to the circuit board, the light emitting part penetrates through the first sub through hole and partially stretches into the second sub through hole, the receiver comprises a photosensitive part and a second connecting part which are connected with each other, the second connecting part is connected to the circuit board, and the photosensitive part penetrates through the third sub through hole and partially stretches into the fourth sub through hole; wherein, the light-emitting part and the photosensitive part are fixedly connected with the inner shell through the bonding piece.

In some embodiments, the second mounting groove is filled with a potting compound that at least wraps the circuit board.

In a second aspect, the present utility model provides a range hood comprising a hood body and a detection arrangement as described above. The main body of the smoke machine is provided with a smoke discharge channel, and the detection device is arranged in the smoke discharge channel.

In the detection device of the present utility model, the transmitter and the receiver are integrated on the same circuit board, compared with the detection device in the related art, so that the circuit board is not required to be provided separately for the transmitter and the receiver, thereby contributing to downsizing of the detection device. Furthermore, in the present utility model, the integrated transmitter and receiver are provided in the housing, so that the contamination and corrosion effects of moisture and smoke in the air on the transmitter and receiver and the circuit board can be reduced. In the range hood, the detection device is adopted and is arranged in a smoke discharge channel of the range hood. Because the volume of the detection device is smaller than that of the detection device in the related technology, even if the detection device is arranged in the smoke exhaust channel of the smoke exhaust ventilator, the detection device has smaller blocking influence on the smoke exhaust channel of the smoke exhaust ventilator, and does not obstruct the normal emission of smoke or water vapor.

Drawings

In order to more clearly illustrate the embodiments of the present utility model or the technical solutions in the prior art, the drawings that are required in the embodiments or the description of the prior art will be briefly described, and it is obvious that the drawings in the following description are only some embodiments of the present utility model, and other drawings may be obtained according to the structures shown in these drawings without inventive effort for a person skilled in the art.

Fig. 1 is a schematic structural view of a range hood according to an embodiment of the present utility model;

FIG. 2 is a schematic diagram of a detecting device according to an embodiment of the present utility model;

FIG. 3 is a schematic cross-sectional view of the structure of FIG. 2 along the P-P direction;

FIG. 4 is an enlarged view of F1 of FIG. 3;

FIG. 5 is an enlarged view of F2 of FIG. 3;

FIG. 6 is an exploded view of a detection device according to an embodiment of the present utility model;

fig. 7 is a schematic diagram of the optical domain of the transmitter and the sensing range of the receiver of the detection device according to the embodiment of the present utility model.

Reference numerals illustrate:

100. a detection device; 1. a housing; 11. a housing; 111. a first mounting groove; 12. an inner case; 121. a second mounting groove; 122. a first collar; 123. a second convex ring; 13. a cover plate; 14. a first through hole; 141. a first sub-via; 141a, a first light inlet; 141b, a first light emitting end; 142. a second sub-via; 15. a second through hole; 151. a third sub-via; 151a, a second light inlet; 151b, a second light emitting end; 152. a fourth sub-via; 2. a circuit board; 3. a transmitter; 31. a light emitting section; 311. a first flange portion; 32. a first connection portion; 4. a receiver; 41. a photosensitive part; 411. a second flange portion; 42. a second connecting portion; 5. an electromagnetic shielding structure; 6. an adhesive member; 61. a first annular adhesive member; 62. a second annular adhesive member; 7. filling colloid; 200. a range hood; 210. a tobacco machine main body; 2101. a smoke collecting part; 2102. a smoke feeding pipe; 2103. a smoke exhaust pipe; a1, an accommodating cavity; a2, a first conical region; a3, a second conical region; a4, overlapping part; b1, positioning columns; b2, positioning holes.

Detailed Description

For the purpose of making the objects, technical solutions and advantages of the present utility model more apparent, the following detailed description of the embodiments of the present utility model will be given with reference to the accompanying drawings.

When the following description refers to the accompanying drawings, the same numbers in different drawings refer to the same or similar elements, unless otherwise indicated. The implementations described in the following exemplary examples do not represent all implementations consistent with the utility model. Rather, they are merely examples of apparatus and methods consistent with some aspects of the utility model as detailed in the accompanying claims.

In the description of the present utility model, it should be understood that the terms "first," "second," and the like are used for descriptive purposes only and are not to be construed as indicating or implying relative importance. The specific meaning of the above terms in the present utility model will be understood in specific cases by those of ordinary skill in the art. Furthermore, in the description of the present utility model, unless otherwise indicated, "a plurality" means two or more. "and/or", describes an association relationship of an association object, and indicates that there may be three relationships, for example, a and/or B, and may indicate: a exists alone, A and B exist together, and B exists alone. The character "/" generally indicates that the context-dependent object is an "or" relationship.

Unless defined otherwise, all technical and scientific terms used herein have the same meaning as commonly understood by one of ordinary skill in the art to which this utility model belongs. The terminology used in the description presented herein is for the purpose of describing particular embodiments only and is not intended to be limiting of the utility model. The term "and/or" as used herein includes any and all combinations of one or more of the associated listed items.

It will also be understood that when an element is referred to as being "fixed to" another element, it can be directly on the other element or intervening elements may also be present. When an element is referred to as being "connected" to another element, it can be directly connected to the other element or intervening elements may also be present. When an element is referred to as being "disposed on" another element, it can be directly on the other element or intervening elements may also be present.

The present utility model will be described in further detail with reference to the drawings and examples, in order to make the objects, technical solutions and advantages of the present utility model more apparent.

The embodiment of the utility model provides a range hood 200. As shown in fig. 1, the range hood 200 of the present embodiment includes a hood main body 210 and the detection device 100 provided in the above embodiment. The main body 210 of the cigarette maker is formed with a discharge flue in which the detecting device 100 is disposed. The main body 210 includes a smoke collecting portion 2101, a smoke feeding tube 2102 and a smoke discharging tube 2103. One end of the smoke feeding pipe 2102 is connected with the smoke collecting part 2101, the other end of the smoke feeding pipe 2102 is connected with the smoke discharging pipe 2103, and the smoke discharging pipe 2103 is communicated with a chimney. The smoke feed tube 2102 and the smoke discharge tube 2103 together form a smoke discharge channel of the main body 210 of the cigarette machine.

As shown in fig. 2 and 3, the detection device 100 includes a housing 1, a circuit board 2, a transmitter 3, and a receiver 4. The housing 1 has a housing cavity A1, a circuit board 2 is provided in the housing cavity A1, and the transmitter 3 and the receiver 4 are both provided on the circuit board 2. Wherein, the shell 1 is provided with a first through hole 14 and a second through hole 15 which are communicated with the accommodating cavity A1. The emitter 3 is capable of emitting outgoing light to the outside of the housing 1 via the first through hole 14. The outgoing light passes through a transparent medium such as: light is easily refracted when water drops or oil drops are dropped. Optionally, the outgoing light is light with a wavelength less than 400 nm. When the emitted light irradiates the particles in the air, such as smoke or moisture, the scattered light is generated due to the reflection on the surface of the opaque particles and the refraction of the transparent particles, and a part of the scattered light is received by the receiver 4 through the second through hole 15.

Hereinafter, the scattered light that can be received by the receiver 4 through the second through-hole 15 is defined as the retroreflected light (the retroreflected light is the same meaning as described below).

In the detecting device 100 of the present embodiment, the transmitter 3 and the receiver 4 are integrated on the same circuit board 2, compared with the detecting device in the related art, and therefore, it is not necessary to provide the circuit board 2 for the transmitter 3 and the receiver 4 separately, which is advantageous in reducing the volume of the detecting device 100. Since the volume of the detection device 100 of the present embodiment is smaller than that of the detection device in the related art, even if the detection device is disposed in the exhaust duct of the range hood 200, the blocking effect on the exhaust duct of the range hood 200 is small, and the normal emission of the smoke or moisture of the range hood 200 of the present embodiment is not hindered.

Moreover, in the present embodiment, the circuit board 2 is disposed in the housing 1, so that the contact between the circuit board 2 and moisture and smoke in the air can be reduced, and the contamination and corrosion of the circuit board 2 by moisture and smoke can be reduced, which is advantageous for improving the durability of the detection device 100.

In this embodiment, the setting position of the detecting device 100 can be reasonably adjusted according to actual needs. For example: the detection device 100 may be provided on the smoke collecting portion 2101, whereby the smoke concentration of the stove hearth can be directly detected. Another example is: the detecting device 100 may be disposed in the smoke exhaust pipe 2103 or the smoke delivery pipe 2102 so as not to be exposed to the outside of the range hood 200, so that the overall appearance of the range hood 200 is tidy.

In the present embodiment, as shown in fig. 7, in order for the receiver 4 to be able to receive the retroreflected light, the first through hole 14 and the second through hole 15 are provided in such a manner that at least an overlapping portion A4 must exist between the optical field of the outgoing light formed by the emitter 3 through the first through hole 14 and the sensing range formed by the receiver 4 through the second through hole 15.

Here, the light field of the outgoing light formed by the emitter 3 means a region filled with the outgoing light, as the first cone region A2 shown in fig. 7. Any part of the object such as soot, water drop, and oil drop entering the first tapered region is irradiated with the emitted light (the meaning of the light field described below is the same).

The sensing range of the receiver 4 means a region that can be sensed by the receiver 4 when the reflected light enters the range, as the second cone region A3 shown in fig. 7. When the reflected light generated by the light emitted from the object such as soot, water droplet, or oil droplet enters the second cone region, the reflected light is sensed by the receiver 4 (the meaning of the sensing range is the same).

Therefore, when there is at least an overlapping portion A4 between the light field of the outgoing light formed by the emitter 3 and the sensing range formed by the receiver 4, if the microparticles in the air enter the overlapping portion A4 between the light field and the sensing range, the outgoing light is immediately irradiated to generate the retroreflected light, and at the same time, the retroreflected light is also sensed by the receiver 4, thereby completing the detection of the concentration of the microparticles in the air. Based on the above principle, the overlapping portion A4 between the optical domain and the sensing range of the present embodiment can be flexibly set according to actual design needs.

In some of these embodiments, as shown in fig. 3, the housing 1 is further provided with an electromagnetic shielding structure 5 surrounding the outside of the circuit board 2, and the electromagnetic shielding structure 5 is made of a metal material. When the electromagnetic shielding structure 5 surrounds the outer side of the circuit board 2, an electromagnetic barrier wrapping the circuit board 2 can be formed, so that interference of external electromagnetic waves to the circuit board 2, the transmitter 3 and the receiver 4 can be prevented, and the anti-interference performance of the detection device 100 can be improved. In an alternative of this embodiment, the electromagnetic shielding structure 5 is an electromagnetic shielding film such as a metal thin film or a metal paper. The electromagnetic shielding film is attached to the inner wall or the outer wall of the housing 1. Of course, the electromagnetic shielding films can also be adhered to the inner wall and the outer wall of the shell 1 to form a dual electromagnetic barrier, so that interference of external electromagnetic waves to the circuit board 2, the transmitter 3 and the receiver 4 is further reduced. In another alternative of this embodiment, the electromagnetic shielding structure 5 is a metal coating. The metal coating is coated on the inner wall or the outer wall of the housing 1. As above, the metal coating may also be coated on both the inner wall and the outer wall of the housing 1. In a further alternative of the present embodiment, the electromagnetic shielding structure 5 is a metallic shielding powder embedded in the wall of the housing 1. For example: the housing 1 of this alternative is manufactured by an injection molding process in which metal powder is uniformly mixed in the molten raw material of the housing 1, and after the injection molding is completed, the metal powder is uniformly distributed in the wall of the housing 1, thereby enabling the electromagnetic shield to be formed.

In some of these embodiments, as shown in connection with fig. 3 and 6, the number of receivers 4 is plural, with plural receivers 4 being enclosed around a single transmitter 3. Correspondingly, a plurality of second through holes 15 are formed in the housing 1, and the plurality of second through holes 15 are surrounded by a single first through hole 14. The plurality of second through holes 15 are in one-to-one correspondence with the plurality of receivers 4, and the receivers 4 can receive the retroreflected light formed by the outgoing light applied to the detected smoke or water vapor through the corresponding second through holes 15.

In the present embodiment, the plurality of receivers 4 are disposed around the single emitter 3, so that the overlapping area between the light field formed by the emitter 3 and the sensing range of the receiver 4 is increased, so that the detecting device 100 can collect more retro-reflected light, which is beneficial to improving the accuracy of the detection result of the smoke or moisture concentration of the detecting device 100.

In some of these embodiments, as shown in fig. 3 to 5, the housing 1 includes an outer shell 11, an inner shell 12, and a cover plate 13. The outer housing 11 has a first mounting groove 111 defined by an inner wall of the outer housing 11, and the inner housing 12 is disposed within the first mounting groove 111. The inner case 12 has a second mounting groove 121 defined by an inner wall of the inner case 12, and the circuit board 2 is placed in the second mounting groove 121. The cover plate 13 is coupled to the same side of the outer case 11 and the inner case 12 to cover the first mounting groove 111 and the second mounting groove 121. Wherein, the cover plate 13 and the inner shell 12 cooperate to form a containing cavity A1, that is, the cover plate 13 and the second mounting groove 121 enclose to form the containing cavity A1. The first through hole 14 includes a first sub through hole 141 and a second sub through hole 142, which are mutually communicated, the first sub through hole 141 is formed on the outer shell 11, and the second sub through hole 142 is formed on the inner shell 12. The second through hole 15 includes a third sub through hole 151 and a fourth sub through hole 152 which are communicated with each other, the third sub through hole 151 is opened on the outer case 11, and the fourth sub through hole 152 is opened on the inner case 12.

In the present embodiment, the housing 1 has a double-layered structure of the outer case 11 and the inner case 12, and when the detecting device 100 is subjected to an external impact, the outer case 11 and the inner case 12 play a role of buffering, so that the circuit board 2 is not directly affected by the external impact force, and the connection breakage of the transmitter 3 and the receiver 4 and other electronic components on the circuit board 2 due to the impact is reduced, thereby improving the impact resistance of the detecting device 100.

Moreover, the emitter 3 may be inserted into the first and second sub through holes 141 and 142, and the receiver 4 may be inserted into the third and fourth sub through holes 151 and 152, and at this time, the emitter 3 blocks the first and second sub through holes 141 and 142, and the receiver 4 blocks the third and fourth sub through holes 151 and 152, and on the basis of this structure, the cover 13 and the second mounting groove 121 may be engaged with each other to form an additional sealing chamber in addition to the sealed receiving chamber A1, so that even if the microparticles in the air flow into the housing 11, the circuit board 2 and the emitter 3 and the receiver 4 disposed in the receiving chamber A1 are not directly affected, thereby reducing the adhesion of the microparticles in the air to the circuit board 2, resulting in the occurrence of a short circuit between the emitter 3 and the receiver 4 and other electronic components, thereby improving the environmental resistance of the detection apparatus 100. As shown in fig. 3, the second mounting groove 121 is filled with a potting body 7 at least wrapping the circuit board 2, and the potting body 7 is manufactured by a potting process. The potting compound 7 may also encapsulate the electronic components of the circuit board 2 other than the transmitter 3 and the receiver 4, as desired. Since the circuit board 2 is wrapped by the potting compound 7, even if the microparticles in the air flow into the accommodating cavity A1, the microparticles cannot contact with the circuit board 2, so that the situation that the microparticles adhere to the circuit board 2, and the short circuit of the transmitter 3, the receiver 4 and other electronic components or the corrosion of the circuit board 2 and the functional modules and electronic devices on the circuit board 2 occurs can be reduced.

In this embodiment, as shown in fig. 4, the emitter 3 includes a light emitting portion 31 and a first connecting portion 32 connected to each other, the first connecting portion 32 is connected to the circuit board 2, and the light emitting portion 31 is disposed through the first sub-through hole 141 and partially extends into the second sub-through hole 142. As shown in fig. 5, the receiver 4 includes a photosensitive portion 41 and a second connection portion 42 connected to each other, the second connection portion 42 being connected to the circuit board 2, the photosensitive portion 41 being disposed through the third sub-through hole 151 and partially extending into the fourth sub-through hole 152. After the outgoing light emitted from the light-emitting portion 31 irradiates the micro particles in the air, such as smoke or moisture, through the second sub-through holes 142, the light-sensing portion 41 receives the reflected light through the fourth sub-through holes 152 due to reflection on the surface of the smoke particles and refraction of the water drops, so as to achieve the concentration of the smoke or moisture in the external environment. Wherein the light field that the emitter 3 is capable of forming and the detection area of the receiver 4 at least partially overlap in a plane perpendicular to the axis of the first sub-via 141, thereby enabling the receiver 4 to sense the retro-reflected light.

In an alternative of the present embodiment, as shown in fig. 3 and 6, a plurality of positioning holes B2 are formed in the circuit board 2, and a plurality of positioning posts B1 corresponding to the plurality of positioning holes B2 are disposed on the bottom of the second mounting groove 121, where each positioning post B1 is inserted into a corresponding positioning hole B2 to limit the relative movement between the circuit board 2 and the inner case 12. As shown in fig. 4 and 5, the light emitting portion 31 and the light receiving portion 41 are fixedly connected to the inner case 12 by the adhesive 6, and the first connecting portion 32 and the second connecting portion 42 are connected to the circuit board 2, respectively, so that the relative movement between the light emitting portion 31 and the first connecting portion 32 and the relative movement between the light receiving portion 41 and the second connecting portion 42 can be reduced, and the possibility of breakage between the light emitting portion 31 and the first connecting portion 32 or between the light receiving portion 41 and the second connecting portion 42 can be reduced.

In an alternative of this embodiment, as shown in fig. 4, a first flange portion 311 is protruding from an end of the light emitting portion 31 relatively near the first connecting portion 32, and a first annular adhesive member 61 is further sleeved on the light emitting portion 31, where the first annular adhesive member 61 is used to connect the first flange portion 311 and a side surface of the inner case 12 facing the circuit board 2. As shown in fig. 5, a second flange 411 is protruding from an end of the photosensitive portion 41 that is relatively close to the second connection portion 42, and a second annular adhesive member 62 is further sleeved on the photosensitive portion 41, where the second annular adhesive member 62 is used to connect the second flange 411 and a side surface of the inner case 12 facing the circuit board 2. In the present embodiment, the first flange portion 311 is fixedly connected to the inner case 12 by the first annular adhesive member 61, and the second flange portion 411 is fixedly connected to the inner case 12 by the second annular adhesive member 62, so that the gap formed between the light emitting portion 31 and the inner case 12 and the gap formed between the light sensing portion 41 and the inner case 12 are closed, thereby further improving the sealing property of the accommodating chamber A1, and reducing the possibility that the microparticles in the air flow into the accommodating chamber A1 through the gap between the light emitting portion 31 and the second sub-through hole 142 or through the gap between the light sensing portion 41 and the fourth sub-through hole 152 to contaminate the circuit board 2.

In another alternative of the present embodiment, as shown in fig. 4 and 5, the side of the inner case 12 facing the circuit board 2 is provided with a first collar 122 surrounding the second sub-through hole 142 and a second collar 123 surrounding the fourth sub-through hole 152. The first annular adhesive 61 is located inside the first collar 122 and the second annular adhesive 62 is located inside the second collar 123. The inner side walls of the first and second collars 122, 123 restrict radial movement of the first and second annular adhesive members 61, 62, respectively, preventing relative movement between the first and second annular adhesive members 61, 62 and the inner casing 12 along the surface of the inner casing 12, thereby enabling a reduced likelihood of peeling of the first and second annular adhesive members 61, 62 from the inner casing 12.

In some embodiments, as shown in fig. 3 and 6, an electromagnetic shielding structure 5 is disposed between the outer shell 11 and the inner shell 12 and on the cover plate 13, and the electromagnetic shielding structure 5 surrounds the outer side of the circuit board 2 in space, so that an electromagnetic barrier wrapping the circuit board 2 can be formed, thereby preventing interference of external electromagnetic waves to the circuit board 2, the transmitter 3 and the receiver 4, and being beneficial to improving the anti-interference performance of the detection device 100.

In an alternative of this embodiment, the electromagnetic shielding structure 5 is an electromagnetic shielding film such as a metal thin film or a metal paper. Wherein:

the electromagnetic shielding film can be attached to the side of the cover plate 13 facing away from the housing 11 and the inner wall or the outer wall of the housing 11, so as to facilitate the attachment work of the electromagnetic shielding film.

The electromagnetic shielding film may also be attached to the side of the cover plate 13 facing the housing 11, and to the inner wall or outer wall of the housing 11, to reduce the possibility of contamination of the electromagnetic shielding film by external micro particles.

The electromagnetic shielding film may also be attached to a side of the cover plate 13 facing away from the outer case 11, and to an outer wall of the inner case 12, so as to be able to maximize an electromagnetic shielding range of the electromagnetic shielding film.

The electromagnetic shielding films can be attached to the opposite sides of the cover plate 13, the inner wall and the outer wall of the outer shell 11 and the outer wall of the inner shell 12 to form a multi-cell barrier, so as to improve the electromagnetic interference resistance of the detection device 100.

In another alternative of the present embodiment, the electromagnetic shielding structure 5 is a metal coating, and the metal component used to form the metal coating may be at least one of silver, copper, iron, nickel, zinc, and gold, but is not limited thereto. Wherein:

a metal coating may be coated on a side of the cover plate 13 facing away from the housing 11, and on an inner wall or an outer wall of the housing 11 to facilitate a coating work of the metal coating.

A metal coating may also be coated on the side of the cover plate 13 facing the housing 11, as well as on the inner or outer wall of the housing 11, to reduce the possibility of contamination of the metal coating by external micro particles.

The metal coating may also be coated on the side of the cover plate 13 facing away from the outer shell 11, and on the outer wall of the inner shell 12, to enable the electromagnetic shielding range of the metal coating to be maximized.

The metal coating may be coated on the opposite sides of the cover plate 13, the inner and outer walls of the outer case 11 and the outer wall of the inner case 12 to form a multi-cell barrier, thereby improving the electromagnetic interference resistance of the detection apparatus 100.

In some embodiments, as shown in fig. 4 and 5, the first sub-through hole 141 includes a first light-entering end 141a relatively close to the emitter 3 and a first light-exiting end 141b relatively far from the emitter 3, and the aperture of the first light-entering end 141a is smaller than that of the first light-exiting end 141b, so that the diffusion of the outgoing light is facilitated, and the irradiation area of the emitter 3 is further facilitated to be increased. And the third sub-through hole 151 includes a second light incident end 151a relatively far from the receiver 4 and a second light emergent end 151b relatively close to the receiver 4, where the aperture of the second light incident end 151a is larger than that of the second light emergent end 151b, which is beneficial to expanding the sensing area of the receiver 4, thereby increasing the sensing range of the receiver 4.

As an example, the first sub-via 141 includes a first portion relatively close to the second sub-via 142 and a second portion relatively far from the second sub-via 142. Wherein the aperture of the second portion gradually increases in a direction away from the second sub-through hole 142, and the aperture of the first portion is equal to the minimum aperture of the second portion, so that the cross section of the first sub-through hole 141 along the hole axis has one section with the same aperture and another section with a trapezoid shape.

The aperture of the third sub-through hole 151 is gradually increased in a direction away from the fourth sub-through hole 152, that is, the aperture of the third sub-through hole 151 is gradually increased in a direction in which the third sub-through hole 151 is away from the fourth sub-through hole 152, so that the cross section of the third sub-through hole 151 along the hole axis is trapezoidal. Of course, the aperture of the first sub-through hole 141 may also be gradually increased in a direction away from the second sub-through hole 142, that is, the aperture of the first sub-through hole 141 is gradually increased in a direction away from the second sub-through hole 142, so that the cross section of the first sub-through hole 141 along the hole axis is trapezoidal.

Since the first sub-through hole 141 and the third sub-through hole 151 each have a trapezoid-shaped portion in cross section along the hole axis, that is, the first sub-through hole 141 and the third sub-through hole 151 are horn-shaped through holes, so that the optical field formed by the emitter 3 through the first sub-through hole 141 and the sensing range formed by the receiver 4 through the third sub-through hole 151 are gradually widened in the group in the propagation direction of the outgoing light, even if the axis of the first sub-through hole 141 and the axis of the third sub-through hole 151 are arranged in parallel with each other, an overlapping portion A4 can be formed between the optical field formed by the emitter 3 and the sensing range of the receiver 4 to enable detection of the concentration of fine particles in the air. Of course, when the axis of the first sub-through hole 141 and the axis of the third sub-through hole 151 intersect, the overlapping portion A4 is more easily formed between the optical field formed by the emitter 3 and the sensing range of the receiver 4, which is more favorable for completing the detection of the concentration of the micro particles in the air.

The same or similar reference numerals in the drawings of the present embodiment correspond to the same or similar components; in the description of the present utility model, it should be understood that, if there is an azimuth or positional relationship indicated by terms such as "upper", "lower", "left", "right", etc., based on the azimuth or positional relationship shown in the drawings, it is only for convenience of describing the present utility model and simplifying the description, but it is not indicated or implied that the apparatus or element referred to must have a specific azimuth, be constructed and operated in a specific azimuth, and thus terms describing the positional relationship in the drawings are merely illustrative and should not be construed as limitations of the present patent, and specific meanings of the terms described above may be understood by those skilled in the art according to specific circumstances.

The foregoing description of the preferred embodiments of the utility model is not intended to be limiting, but rather is intended to cover all modifications, equivalents, and alternatives falling within the spirit and principles of the utility model.

Claims (11)

1. A detection apparatus, characterized by comprising:

the shell is provided with a containing cavity, and a first through hole and a second through hole which are communicated with the containing cavity are formed in the shell;

the circuit board is arranged in the accommodating cavity;

an emitter disposed on the circuit board, the emitter being capable of emitting outgoing light to an outside of the housing through the first through hole; and

the receiver is arranged on the circuit board and can receive the retroreflected light formed after the emergent light acts on the detected smoke or water vapor through the second through hole;

wherein the first through hole and the second through hole are arranged such that an overlapping portion is formed between a light field of outgoing light formed by the emitter through the first through hole and a sensing range formed by the receiver through the second through hole.

2. The detecting device according to claim 1, wherein an electromagnetic shielding structure surrounding the outside of the circuit board is further provided on the housing, and the electromagnetic shielding structure is used for preventing external electromagnetic waves from interfering with the circuit board, the transmitter and the receiver.

3. The detection device according to claim 2, wherein the electromagnetic shielding structure is an electromagnetic shielding film, and the electromagnetic shielding film is attached to an inner wall and/or an outer wall surface of the housing; or alternatively

The electromagnetic shielding structure is a metal coating, and the metal coating is coated on the inner wall and/or the outer wall surface of the shell; or alternatively

The electromagnetic shielding structure is made of metal shielding powder particles which are embedded in the wall body of the shell.

4. The detecting device according to claim 1, wherein the plurality of receivers are provided, the plurality of receivers are provided around the emitter, the plurality of second through holes are provided around the first through hole, the plurality of second through holes are provided in one-to-one correspondence with the plurality of receivers, and the receivers can receive the reflected light formed by the outgoing light applied to the detected smoke or water vapor through the corresponding second through holes.

5. The detection apparatus according to any one of claims 1 to 4, wherein the housing includes:

a housing having a first mounting slot;

an inner housing having a second mounting groove, the inner housing being disposed within the first mounting groove; and

the cover plate is connected to the same side of the outer shell and the inner shell so as to cover the first mounting groove and the second mounting groove, and the cover plate and the inner shell are matched to form the accommodating cavity;

the first through hole comprises a first sub through hole and a second sub through hole which are communicated with each other, the first sub through hole is formed in the outer shell, and the second sub through hole is formed in the inner shell;

the second through hole comprises a third sub through hole and a fourth sub through hole which are communicated with each other, the third sub through hole is formed in the outer shell, and the fourth sub through hole is formed in the inner shell.

6. The detecting device according to claim 5, wherein the emitter includes a light-emitting portion and a first connecting portion connected to each other, the first connecting portion being connected to the circuit board, the light-emitting portion being provided to pass through the first sub-through hole and partially extend into the second sub-through hole, the receiver including a light-sensing portion and a second connecting portion connected to each other, the second connecting portion being connected to the circuit board, the light-sensing portion being provided to pass through the third sub-through hole and partially extend into the fourth sub-through hole;

the light field that the emitter is capable of forming and the detection area of the receiver at least partially overlap in a plane perpendicular to the axis of the first sub-via.

7. The detection device of claim 5, wherein the first sub-aperture comprises a first light entry end relatively close to the emitter and a first light exit end relatively far from the emitter, the first light entry end having a smaller aperture than the first light exit end;

the third sub-through hole comprises a second light inlet end relatively far away from the receiver and a second light outlet end relatively close to the receiver, and the aperture of the second light inlet end is larger than that of the second light outlet end.

8. The detecting device according to claim 7, wherein the aperture of the first sub-through hole gradually increases in a direction away from the second sub-through hole, or the first sub-through hole includes a first portion relatively close to the second sub-through hole and a second portion relatively away from the second sub-through hole, the aperture of the second portion gradually increasing in a direction away from the second sub-through hole, the aperture of the first portion being equal to the minimum aperture of the second portion;

the aperture of the third sub-through hole gradually increases in a direction away from the fourth sub-through hole, and the axis of the first sub-through hole and the axis of the third sub-through hole are parallel to each other.

9. The detecting device according to claim 5, wherein the emitter includes a light-emitting portion and a first connecting portion connected to each other, the first connecting portion being connected to the circuit board, the light-emitting portion being provided to pass through the first sub-through hole and partially extend into the second sub-through hole, the receiver including a light-sensing portion and a second connecting portion connected to each other, the second connecting portion being connected to the circuit board, the light-sensing portion being provided to pass through the third sub-through hole and partially extend into the fourth sub-through hole;

wherein, the light-emitting part and the photosensitive part are fixedly connected with the inner shell through an adhesive piece.

10. The device of claim 5, wherein the second mounting groove is filled with a potting compound that encapsulates at least the circuit board.

11. A range hood comprising a hood body and a detection apparatus as claimed in any one of claims 1 to 10, the hood body being formed with a smoke outlet, the detection apparatus being disposed within the smoke outlet.