An Adaptive Laser Methane Sensor Based on MEMS Optical System

Abstract

The present invention relates to the technical field of laser methane sensors, and particularly to an adaptive laser methane sensor based on a MEMS optical system, which includes a main controller, a housing, a laser assembly, and a receiver; it also includes a plurality of reflectors, an air inlet hood, an air inlet notch, and an air filter element. The emission end of the laser assembly and the receiving end of the receiver respectively extend into both ends of the housing. The cross-section of the gas chamber of the housing is a regular polygon. The plurality of reflectors are respectively installed on the inner wall of the gas chamber. The laser assembly emits a laser beam towards the reflectors, and the laser beam is spirally emitted between the plurality of reflectors towards the receiver. The air inlet hood is installed on the air inlet of the housing, and the air inlet notch is installed on the air inlet hood. The air inlet notch is close to the outer wall of the housing, and the air filter element is installed at the opening of the air inlet notch. The air inlet notch and the air inlet hood are communicated with the gas chamber through the air inlet of the housing; it adopts a broken-line spiral optical path, which greatly increases the optical path of the laser beam and improves the detection accuracy of methane.

Description

Technical Field

[0001] The present invention relates to the technical field of laser methane sensors, and particularly to an adaptive laser methane sensor based on a MEMS optical system. Background Art

[0002] A MEMS optical system is a system that realizes optical functions through tiny mechanical movements. It combines microelectronic technology, micro-nano processing technology, and mechanical engineering principles, and uses the mass manufacturing technology of the semiconductor industry to achieve miniaturization, extraordinary precision, and reliability.

[0003] A laser methane sensor is a sensor that uses laser spectroscopy technology to achieve high-precision gas detection. In the technical field of methane concentration detection, a MEMS optical system is widely used to realize the adaptability of detection equipment and improve the detection accuracy of methane. For example, a laser methane telemeter based on a VCM motor proposed in a Chinese patent application with publication number CN115508283A adjusts the position of the VCM motor based on distance parameters to keep the outgoing light spot of the collimating lens at the optimal size, so as to achieve the best detection effect regardless of the distance of the detection object.

[0004] In the prior art, a variety of compact laser methane sensors have also been proposed. For example, a compact long optical path laser methane sensor proposed in a Chinese utility model patent with publication number CN218917183U forms a folded reflection optical path by using four laser reflection lenses to obtain a long optical path, thereby improving the detection sensitivity and accuracy of the laser methane sensor.

[0005] However, the optical path formed by the reflection of the laser between multiple reflectors in the above-mentioned laser methane sensor is in a plane, and each reflector only reflects the laser beam once, resulting in an increase in the complexity of the structure but no obvious increase in the optical path of the laser beam, which is not conducive to improving the detection accuracy of methane. Summary of the Invention

[0006] To solve the above technical problems, the present invention provides an adaptive laser methane sensor based on a MEMS optical system, which adopts a broken-line spiral optical path to greatly increase the optical path of the laser beam and improve the detection accuracy of methane.

[0007] An adaptive laser methane sensor based on a MEMS optical system of the present invention includes a main controller, a housing, a laser assembly, and a receiver. The housing is mounted on the main controller, and both the laser assembly and the receiver are mounted on the housing. It further includes a plurality of reflectors, an air inlet hood, an air inlet notch, and an air filter element. The housing is provided with an air chamber along the axis. The air chamber is provided with an air inlet at the end of the housing away from the main controller, and an air outlet at the end of the housing close to the main controller. The emitting end of the laser assembly and the receiving end of the receiver respectively extend into both ends of the air chamber. The cross-section of the air chamber is a regular polygon. A plurality of reflectors are respectively mounted on the inner wall of the air chamber. The laser assembly emits a laser beam towards the reflectors, and the laser beam is reflected between the plurality of reflectors, so that the laser beam is spirally emitted towards the receiver between the plurality of reflectors. The air inlet hood is mounted on the air inlet of the housing, and the air inlet notch is mounted on the air inlet hood. The air inlet notch is close to the outer wall of the housing, and the air filter element is mounted on the opening of the air inlet notch. The air inlet notch and the air inlet hood are communicated with the air chamber through the air inlet of the housing. During operation, the gas is filtered by the air filter element and then enters the inner air chamber through the air inlet notch, the air inlet hood, and the air inlet of the housing. The gas is discharged through the air outlet after passing through the air chamber. The main controller controls the laser assembly to be turned on. The laser assembly emits a laser beam towards the reflectors. The laser beam is reflected by the plurality of reflectors and then emitted towards the receiver in a broken-line spiral shape. By adjusting the angle between the laser emitted by the laser assembly and the axis of the air chamber of the housing, the number of layers of the laser beam between the laser assembly and the receiver can be adjusted. The smaller the angle, the more layers, and the longer the optical path length. By adjusting the focus of the laser emitted by the laser assembly, the spot size of the laser beam reflected on the reflector can be adjusted. Since the spot diffuses each time the laser beam is reflected, the more laser reflection layers, the smaller the spot adjustment, so that the size of the laser spot received by the receiver is appropriate, realizing self-adaptation. Compared with the prior art, since the optical path formed by the laser beam reflected between the plurality of reflectors is not in a plane, each reflector reflects the laser beam multiple times, thereby greatly increasing the optical path of the laser beam with limited structural modification and improving the detection accuracy of methane.

[0008] Preferably, the laser assembly includes an angle adjustment micromotor, a laser emitter, and a VCM motor. The angle adjustment micromotor is mounted on the housing. The laser emitter is mounted on the movable end of the angle adjustment micromotor. The VCM motor is mounted on the emitting head of the laser emitter, and a collimating lens is mounted on the movable end of the VCM motor. The movable end of the angle adjustment micromotor drives the laser emitter to swing, thereby adjusting the angle between the laser beam and the axis of the gas chamber of the housing, thus adjusting the number of reflection levels of the laser beam, achieving an adaptive adjustment of the optical path length, being applicable to measurement requirements of different precisions. The movable end of the VCM motor extends and retracts to drive the collimating lens to approach or move away from the emitting head of the laser emitter, thereby adjusting the focal position of the laser beam, and further adjusting the size of the laser spot on the reflector and the receiver, so that the size of the spot received by the receiver is optimal. By comparing the intensity of the laser emitted by the laser emitter and the spectral change of the laser received by the receiver, the methane concentration in the gas chamber is detected, achieving an adaptive effect.

[0009] Preferably, the cross-section of the gas chamber of the housing is a regular triangle, a regular quadrilateral, or a regular pentagon, and the number of reflectors matches the number of side walls of the gas chamber of the housing.

[0010] Preferably, it further includes a first motor and an impeller. The first motor is installed inside the gas chamber of the housing. The first motor is located at the air outlet of the gas chamber, and the output shaft of the first motor is installed with the impeller. The first motor drives the impeller to rotate, discharging the gas in the gas chamber of the housing through the air outlet, and sucking the external gas into the gas chamber of the housing through the air filter element, the air intake slot, and the air intake cover, improving the air intake efficiency, and further improving the detection efficiency.

[0011] Preferably, it further includes a first mounting seat and a second mounting seat. A first mounting seat is provided at one end of the housing close to the air inlet, and a first mounting opening is provided at the outer end of the first mounting seat. The first mounting seat is used for mounting the laser assembly. A second mounting seat is provided at one end of the housing close to the air outlet, and a second mounting opening is provided at the outer end of the second mounting seat. The second mounting seat is used for mounting the receiver. By providing the first mounting seat and the second mounting seat, it is convenient to disassemble and assemble the laser assembly and the receiver, and the practicability is good.

[0012] Preferably, it further includes a sub-controller and an electric turntable. The stator of the electric turntable is mounted on the sub-controller, and the main controller is mounted on the rotor of the electric turntable. The sub-controller is electrically connected to the electric turntable. The sub-controller controls the operation of the electric turntable, and the rotor of the electric turntable drives the main controller to rotate, thereby rotating the housing, the air intake cover, and the air intake slot, so as to suck and detect the methane concentration of the gas in different directions of the housing.

[0013] Preferably, it further includes a flange plate. The flange plate is mounted at the bottom of the sub-controller, and the flange plate is provided with mounting holes. The flange plate is mounted on a designated bracket or a designated position through the mounting holes, which is convenient for installation and disassembly.

[0014] Preferably, it further includes an electric slip ring. The electric slip ring is sleeved on the rotor end of the electric turntable. The cable of the sub-controller is electrically connected to the outer ring of the electric slip ring, and the cable of the main controller is electrically connected to the inner ring of the electric slip ring. By setting the electric slip ring, the cable between the main controller and the sub-controller will not be entangled due to the rotation of the main controller, avoiding cable damage and improving reliability.

[0015] Preferably, it further includes an air guide cover, a plurality of metal sheets and a plurality of contacts. The air guide cover is sleeved on the outer wall of the housing. The air guide cover is provided with a cutout for avoiding the air inlet notch. A plurality of air inlet notches are circumferentially arranged on the outer wall of the air guide cover. The plurality of metal sheets are located between the outer wall of the air guide cover and the housing. Both ends of the plurality of metal sheets are not connected to the inner wall of the air guide cover. The plurality of metal sheets are respectively arranged on both sides of the plurality of air inlet notches of the air guide cover. Contacts are installed in the middle of the opposite surfaces of the two metal sheets located on both sides of the same air inlet notch. The plurality of metal sheets located on the left side of the plurality of air inlet notches are electrically connected to one end of the signal cable, and the plurality of metal sheets located on the right side of the plurality of air inlet notches are electrically connected to the other end of the signal cable. The signal cable is electrically connected to the main controller. When the air flow passes through the air guide cover, the air flow blows through the corresponding pairs of metal sheets between several air inlet notches on the windward surface of the air guide cover. Since the air flow velocity between the two metal sheets is faster than the air flow velocity outside the two metal sheets, a pressure difference is generated. The pressure difference causes the two opposite metal sheets to approach each other, making the two contacts on the two metal sheets contact, so that the signal cable is connected to generate a signal. The main controller receives the signal and sends it to the sub-controller through the cable and the electric slip ring. The sub-controller controls the operation of the electric turntable, causing the housing to drive the air guide cover to start rotating. When the air inlet notch rotates to the windward surface, since the air guide cover is provided with a cutout for avoidance at the air inlet notch, the air flow no longer enters the inside of the air guide cover, causing the signal to disappear and the electric turntable to stop, enabling the air inlet notch to automatically face the direction of the air flow, so that methane in the air flow can enter the housing more efficiently for detection, improving the reliability of detection.

[0016] Preferably, the plurality of metal sheets are divided into left and right groups. The plurality of metal sheets located on the left side of the middle plane of the air inlet notch are set as the left group, and the plurality of metal sheets located on the right side of the middle plane of the air inlet notch are set as the right group. The left and right groups of metal sheets are respectively connected to the left signal cable and the right signal cable, and the left signal cable and the right signal cable are both electrically connected to the main controller. When the air flow blows to the left part of the air guide cover, the plurality of metal sheets in the left group approach and drive the plurality of contacts on them to contact, causing the left signal cable to be connected to generate a left signal. The main controller sends the left signal to the sub-controller through the cable and the electric slip ring. The sub-controller controls the rotor of the electric turntable to rotate to the left. Similarly, when the air flow blows to the right part of the air guide cover, the rotor of the electric turntable rotates to the right, so that the air inlet notch can face the direction blown by the air flow more quickly, improving the detection efficiency.

[0017] The beneficial effects of the present invention compared with the prior art are as follows: Since the optical path formed by the reflection of the laser beam between multiple mirrors is not in a plane, each mirror reflects the laser beam multiple times, thereby greatly increasing the optical path of the laser beam with limited structural modifications and improving the detection accuracy of methane. BRIEF DESCRIPTION OF THE DRAWINGS

[0018] Figure 1 is an axonometric partial sectional structural schematic diagram of the present invention;

[0019] Figure 2 is a front sectional structural schematic diagram of the present invention;

[0020] Figure 3 is a side sectional structural schematic diagram of the present invention;

[0021] Figure 4 is a schematic diagram of the reflection route of the optical path of the present invention;

[0022] Figure 5 is an axonometric structural schematic diagram of the present invention;

[0023] Figure 6 is a structural schematic diagram of the present invention in a disassembled state;

[0024] Figure 7 is a structural schematic diagram of structures such as the housing, the first motor, and the impeller;

[0025] Figure 8 is a structural schematic diagram of structures such as the laser assembly, the receiver, and the mirror;

[0026] Figure 9 is a structural schematic diagram of structures such as the air inlet hood, the air inlet notch, and the air filter element;

[0027] Figure 10 is a structural schematic diagram of structures such as the air guide hood, the metal sheet, and the contact point.

[0028] Reference numerals in the drawings: 1, main controller; 2, housing; 3, laser assembly; 4, receiver; 5, mirror; 6, air inlet hood; 7, air inlet notch; 8, air filter element; 9, angle adjustment micro-motor; 10, laser emitter; 11, VCM motor; 12, first motor; 13, impeller; 14, first mounting seat; 15, second mounting seat; 16, sub-controller; 17, electric turntable; 18, flange plate; 19, electrical slip ring; 20, air guide hood; 21, metal sheet; 22, contact point. DETAILED DESCRIPTION OF THE INVENTION

[0029] To facilitate the understanding of the present invention, the present invention will be described more comprehensively below with reference to the relevant drawings. The present invention can be implemented in many different forms and is not limited to the embodiments described herein. On the contrary, these embodiments are provided to make the disclosure of the present invention more thorough and comprehensive. Embodiment 1

[0030] As Figures 1 to 9 shown, an adaptive laser methane sensor based on a MEMS optical system includes a main controller 1, a housing 2, a laser assembly 3, and a receiver 4. The housing 2 is mounted on the main controller 1, and both the laser assembly 3 and the receiver 4 are mounted on the housing 2. It further includes a plurality of reflectors 5, an air inlet hood 6, an air inlet notch 7, and an air filter element 8. The housing 2 is provided with an air chamber along the axis. The air chamber is provided with an air inlet at the end of the housing 2 away from the main controller 1 and an air outlet at the end of the housing 2 close to the main controller 1. The emitting end of the laser assembly 3 and the receiving end of the receiver 4 respectively extend into both ends of the air chamber. The cross-section of the air chamber is a regular polygon. The plurality of reflectors 5 are respectively mounted on the inner wall of the air chamber. The laser assembly 3 emits a laser beam towards the reflector 5, and the laser beam is reflected between the plurality of reflectors 5, so that the laser beam spirally shoots towards the receiver 4 between the plurality of reflectors 5. The air inlet hood 6 is mounted on the air inlet of the housing 2, and the air inlet notch 7 is mounted on the air inlet hood 6. The air inlet notch 7 is close to the outer wall of the housing 2, and the air filter element 8 is mounted on the opening of the air inlet notch 7. The air inlet notch 7 and the air inlet hood 6 are communicated with the air chamber through the air inlet of the housing 2. The laser assembly 3 includes an angle adjustment micro-motor 9, a laser emitter 10, and a VCM motor 11. The angle adjustment micro-motor 9 is mounted on the housing 2, the laser emitter 10 is mounted on the movable end of the angle adjustment micro-motor 9, the VCM motor 11 is mounted on the emitting head of the laser emitter, and a collimating lens is mounted on the movable end of the VCM motor 11. The cross-section of the air chamber of the housing 2 is a regular triangle, a regular quadrilateral, or a regular pentagon, and the number of the reflectors 5 matches the number of the side walls of the air chamber of the housing 2. It further includes a motor 12 and an impeller 13. The motor 12 is mounted inside the air chamber of the housing 2, the motor 12 is located at the air outlet of the air chamber, and the output shaft of the motor 12 is mounted with the impeller 13. It further includes a mounting seat 14 and a mounting seat 15. A mounting seat 14 is provided at one end of the housing 2 close to the air inlet, an installation port 1 is provided at the outer end of the mounting seat 14, and the mounting seat 14 is used for mounting the laser assembly 3. A mounting seat 15 is provided at one end of the housing 2 close to the air outlet, an installation port 2 is provided at the outer end of the mounting seat 15, and the mounting seat 15 is used for mounting the receiver 4.

[0031] During operation, Motor 1 drives the impeller 13 to rotate, exhausting the gas in the air chamber of the housing 2 through the air outlet, and sucking the outside gas into the air chamber of the housing 2 through the air filter 8, the air intake slot 7 and the air intake cover 6. After passing through the air chamber, the gas is exhausted through the air outlet. The main controller 1 controls the laser emitter 10 to turn on, and the laser emitter 10 emits a laser beam. After being reflected by multiple reflectors 5, the laser beam is emitted to the receiver 4 in a broken-line spiral shape. The movable end of the angle adjustment micro-motor 9 drives the laser emitter 10 to swing, thereby adjusting the angle between the laser beam and the axis of the air chamber of the housing 2, and being able to adjust the number of layers of the laser beam between the laser assembly 3 and the receiver 4. The smaller the angle, the more layers there are, and the longer the optical path length. The movable end of the VCM motor 11 expands and contracts to drive the collimating lens to approach or move away from the emitting head of the laser emitter 10, thereby adjusting the focal position of the laser beam, and further adjusting the size of the laser spot on the reflector 5 and the receiver 4. Since the laser spot diffuses each time the laser beam is reflected, the more laser reflection layers there are, the smaller the spot adjustment is, making the size of the laser spot received by the receiver 4 appropriate. By comparing the intensity of the laser emitted by the laser emitter 10 and the spectral change of the laser received on the receiver 4, the methane concentration in the air chamber is detected to achieve an adaptive effect. Compared with the prior art, since the optical path formed by the laser beam reflected between multiple reflectors 5 is not in a plane, each reflector 5 reflects the laser beam multiple times, thereby greatly increasing the optical path of the laser beam with limited structural changes and improving the detection accuracy of methane. Embodiment 2

[0032] As Figure 1 、 Figure 2 、 Figure 5 and Figure 6 shown, on the basis of Embodiment 1, it further includes a sub-controller 16 and an electric turntable 17. The stator of the electric turntable 17 is installed on the sub-controller 16, and the main controller 1 is installed on the rotor of the electric turntable 17. The sub-controller 16 is electrically connected to the electric turntable 17; it further includes a flange plate 18, and the flange plate 18 is installed at the bottom of the sub-controller 16, and the flange plate 18 is provided with mounting holes; it further includes a slip ring 19, and the slip ring 19 is sleeved on the rotor end of the electric turntable 17. The cable of the sub-controller 16 is electrically connected to the outer ring of the slip ring 19, and the cable of the main controller 1 is electrically connected to the inner ring of the slip ring 19.

[0033] The flange plate 18 is installed on the specified bracket or specified position through the mounting holes, which is convenient for installation and disassembly. The sub-controller 16 controls the operation of the electric turntable 17, and the rotor of the electric turntable 17 drives the main controller 1 to rotate, thereby rotating the housing 2, the air intake cover 6 and the air intake slot 7, so as to suck and detect the methane concentration of the gas in different directions of the housing 2. By setting the slip ring 19, the cable between the main controller 1 and the sub-controller 16 will not be entangled due to the rotation of the main controller 1, avoiding cable damage and improving reliability. Embodiment 3

[0034] As Figure 6 and Figure 10 shown, on the basis of Embodiment 2, it further includes an air guide cover 20, a plurality of metal sheets 21 and a plurality of contacts 22. The air guide cover 20 is sleeved on the outer wall of the housing 2. The air guide cover 20 is provided with a slot for avoiding the air inlet notch 7. A plurality of air inlet notches are circumferentially arranged on the outer wall of the air guide cover 20. A plurality of metal sheets 21 are located between the outer walls of the air guide cover 20 and the housing 2. Both ends of the plurality of metal sheets 21 are not connected to the inner wall of the air guide cover 20. The plurality of metal sheets 21 are respectively arranged on both sides of the plurality of air inlet notches of the air guide cover 20. Contacts 22 are installed in the middle of the opposite surfaces of the two metal sheets 21 located on both sides of the same air inlet notch. The plurality of metal sheets 21 located on the left side of the plurality of air inlet notches are electrically connected to one end of a signal cable. The plurality of metal sheets 21 located on the right side of the plurality of air inlet notches are electrically connected to the other end of the signal cable. The signal cable is electrically connected to the main controller 1. The plurality of metal sheets 21 are divided into left and right groups. The plurality of metal sheets 21 located on the left side of the middle plane of the air inlet notch 7 are set as the left group, and the plurality of metal sheets 21 located on the right side of the middle plane of the air inlet notch 7 are set as the right group. The left and right groups of metal sheets 21 are respectively connected to a left signal cable and a right signal cable. The left signal cable and the right signal cable are electrically connected to the main controller 1.

[0035] When the air flow blows to the left part of the air guide cover 20, the air flow blows through several air inlet notches on the windward surface of the left part of the air guide cover 20 between the corresponding pairs of metal sheets 21. Since the air flow velocity between the two metal sheets 21 is faster than the air flow velocity outside the two metal sheets 21, a pressure difference is generated. The pressure difference causes the two opposite metal sheets 21 to approach each other, so that the two contacts 22 on the two metal sheets 21 are in contact, making the left signal cable connected to generate a left signal. The main controller 1 receives the left signal and sends it to the sub-controller 16 through the cable and the electric slip ring 19. The sub-controller 16 controls the operation of the electric turntable 17, so that the housing 2 drives the air guide cover 20 to start rotating to the left. When the air inlet notch 7 rotates to the windward surface, since the air guide cover 20 is provided with a slot for avoidance at the air inlet notch 7, the air flow no longer enters the inside of the air guide cover 20, causing the signal to disappear and the electric turntable 17 to stop, so that the air inlet notch 7 can automatically face the direction of the air flow, enabling the methane in the air flow to enter the housing 2 more efficiently for detection and improving the reliability of the detection. Similarly, when the air flow blows to the right part of the air guide cover 20, the rotor of the electric turntable 17 rotates to the right, so that the air inlet notch 7 faces the direction blown by the air flow more quickly, improving the detection efficiency.

[0036] As Figures 1 to 10As shown in the figure, an adaptive laser methane sensor based on a MEMS optical system of the present invention, when working, first installs the sensor to a specified position through a flange plate 18. When the air flow blows to the left part of the air guide cover 20, the air flow blows through several air inlet notches on the windward surface of the left part of the air guide cover 20 between multiple pairs of metal sheets 21 on the left. The multiple metal sheets 21 on the left group approach and drive the multiple contacts 22 thereon to contact, so that the left signal cable is connected to generate a left signal. Then, the main controller 1 receives the left signal and sends it to the sub-controller 16 through a cable and an electric slip ring 19. The sub-controller 16 controls the operation of the electric turntable 17, so that the housing 2 drives the air guide cover 20 to rotate leftward. When the air inlet notch 7 rotates to the windward surface, since the air guide cover 20 is provided with a relief slot at the air inlet notch 7, the air flow no longer enters the inner side of the air guide cover 20, causing the signal to disappear and the electric turntable 17 to stop, so that the air inlet notch 7 can automatically face the direction of the air flow. Then, the motor 12 drives the impeller 13 to rotate, discharges the gas in the air chamber of the housing 2 through the air outlet, and inhales the outside gas into the air chamber of the housing 2 through the air filter 8, the air inlet notch 7 and the air inlet cover 6. The main controller 1 controls the laser emitter 10 to turn on. The laser emitter 10 emits a laser beam to the reflector 5. The laser beam is reflected by multiple reflectors 5 and then emits to the receiver 4 in a broken-line spiral shape. By adjusting the angle between the laser emitted by the laser emitter 10 and the axis of the air chamber of the housing 2 through the angle adjustment micro-motor 9, the number of laser beam levels between the laser module 3 and the receiver 4 can be adjusted. The smaller the angle, the more levels, and the longer the optical path length. By adjusting the focus of the laser emitted by the laser emitter 10 through the VCM motor 11, the spot size of the laser beam reflected on the reflector 5 can be adjusted. Since the laser beam spot diffuses once every time it is reflected, the more laser reflection levels, the smaller the spot adjustment, so that the size of the laser spot received by the receiver 4 is appropriate. Finally, the methane concentration in the air chamber can be detected by comparing the intensity of the laser emitted by the laser emitter 10 and the spectral change of the laser received on the receiver 4.

[0037] The main functions achieved by the present invention are as follows:

[0038] 1. Adopt a broken-line spiral optical path to greatly increase the optical path of the laser beam with limited structural changes and improve the detection accuracy of methane;

[0039] 2. Realize the adaptive adjustment of the laser beam angle and the laser beam focus through the MEMS optical system;

[0040] 3. Improve the methane detection efficiency by active air extraction;

[0041] 4. Can automatically adjust the orientation of the air inlet notch 7 to make the air inlet notch 7 face the direction of the air flow and improve the detection accuracy.

[0042] An adaptive laser methane sensor based on a MEMS optical system of the present invention has common mechanical installation, connection, or setting methods, and any method that can achieve its beneficial effects can be implemented; the main controller 1, housing 2, laser assembly 3, receiver 4, mirror 5, air filter element 8, angle adjustment micromotor 9, laser emitter 10, VCM motor 11, motor 1 12, impeller 13, sub-controller 16, electric turntable 17, electrical slip ring 19, metal sheet 21, contact 22, cables, and signal cables of an adaptive laser methane sensor based on a MEMS optical system of the present invention are purchased on the market, and those skilled in the art only need to install and operate according to the attached instruction manual without the need for creative labor from those skilled in the art.

[0043] The above are only the preferred embodiments of the present invention. It should be noted that for those of ordinary skill in the art in the technical field, without departing from the technical principle of the present invention, several improvements and modifications can be made, and these improvements and modifications should also be regarded as the protection scope of the present invention.

Claims

1. An adaptive laser methane sensor based on a MEMS optical system, comprising a main controller (1), a housing (2), a laser component (3) and a receiver (4), wherein the housing (2) is mounted on the main controller (1), and the laser component (3) and the receiver (4) are both mounted on the housing (2); characterized in that: The invention also comprises a plurality of reflectors (5), an air intake cover (6), an air intake slot (7) and an air filter element (8); an air chamber is arranged along the axis of the housing (2); an air intake is arranged at an end of the housing (2) away from the main controller (1); an air outlet is arranged at an end of the housing (2) close to the main controller (1); a transmitting end of the laser component (3) and a receiving end of the receiver (4) extend into two ends of the air chamber respectively; the cross section of the air chamber is a regular polygon; a plurality of reflectors (5) are respectively mounted on the inner wall of the air chamber; and the laser component (3) is arranged on the inner wall of the air chamber. (3) emitting a laser beam toward the reflector (5), wherein the laser beam is reflected between the plurality of reflectors (5), so that the laser beam is emitted toward the receiver (4) in a spiral shape between the plurality of reflectors (5); an air intake cover (6) is mounted on the air intake port of the housing (2); an air intake slot (7) is mounted on the air intake cover (6); the air intake slot (7) is close to the outer wall of the housing (2); an air filter element (8) is mounted on the opening of the air intake slot (7); the air intake slot (7) and the air intake cover (6) are connected to the air chamber through the air intake port of the housing (2); The laser assembly (3) comprises an angle-adjusting micromotor (9), a laser emitter (10) and a VCM motor (11); the angle-adjusting micromotor (9) is mounted on the housing (2); the laser emitter (10) is mounted on the movable end of the angle-adjusting micromotor (9); the VCM motor (11) is mounted on the emitter head of the laser emitter; and a collimating lens is mounted on the movable end of the VCM motor (11); It also includes a sub-controller (16) and an electric turntable (17), wherein the stator of the electric turntable (17) is mounted on the sub-controller (16), the main controller (1) is mounted on the rotor of the electric turntable (17), and the sub-controller (16) is electrically connected to the electric turntable (17); It also includes an electric slip ring (19), which is mounted on the rotor end of the electric turntable (17), the cable of the auxiliary controller (16) is electrically connected to the outer ring of the electric slip ring (19), and the cable of the main controller (1) is electrically connected to the inner ring of the electric slip ring (19); The invention also comprises an air guide cover (20), a plurality of metal sheets (21) and a plurality of contacts (22); the air guide cover (20) is sleeved on the outer wall of the shell (2); the air guide cover (20) is provided with a slot for avoiding the air inlet slot (7); a plurality of air inlet slots are provided on the circumference of the outer wall of the air guide cover (20); the plurality of metal sheets (21) are located between the air guide cover (20) and the outer wall of the shell (2); the two ends of the plurality of metal sheets (21) are not connected to the inner wall of the air guide cover (20); and the plurality of metal sheets (21) are not connected to the inner wall of the air guide cover (20). The thin sheets (21) are respectively arranged on both sides of the multiple air inlet slots of the air guide cover (20), and contacts (22) are installed in the middle of the opposite surfaces of the two metal sheets (21) located on both sides of the same air inlet slot. The multiple metal sheets (21) located on the left side of the multiple air inlet slots are electrically connected to one end of the signal cable, and the multiple metal sheets (21) located on the right side of the multiple air inlet slots are electrically connected to the other end of the signal cable, and the signal cable is electrically connected to the main controller (1).

2. The adaptive laser methane sensor based on MEMS optical system according to claim 1, characterized in that: The cross section of the air chamber of the shell (2) is a regular triangle, a regular quadrilateral or a regular pentagon, and the number of the reflectors (5) matches the number of side walls of the air chamber of the shell (2).

3. The adaptive laser methane sensor based on MEMS optical system according to claim 1, characterized in that: It also includes a motor 1 (12) and an impeller (13), wherein the motor 1 (12) is mounted inside the air chamber of the housing (2), the motor 1 (12) is located at the air outlet of the air chamber, and the impeller (13) is mounted on the output shaft of the motor 1 (12).

4. The adaptive laser methane sensor based on MEMS optical system according to claim 1, characterized in that: The invention also comprises a mounting seat 1 (14) and a mounting seat 2 (15), wherein the mounting seat 1 (14) is arranged at one end of the housing (2) close to the air inlet, and a mounting opening 1 is arranged at the outer end of the mounting seat 1 (14), and the mounting seat 1 (14) is used to mount the laser assembly (3); the mounting seat 2 (15) is arranged at one end of the housing (2) close to the air outlet, and a mounting opening 2 is arranged at the outer end of the mounting seat 2 (15), and the mounting seat 2 (15) is used to mount the receiver (4).

5. The adaptive laser methane sensor based on MEMS optical system according to claim 1, characterized in that: It also includes a flange plate (18), which is mounted on the bottom of the auxiliary controller (16), and the flange plate (18) is provided with a mounting hole.

6. The adaptive laser methane sensor based on MEMS optical system according to claim 1, characterized in that: The plurality of metal sheets (21) are divided into two groups, the left and right groups. The plurality of metal sheets (21) located on the left side of the middle plane of the air inlet slot (7) are the left group, and the plurality of metal sheets (21) located on the right side of the middle plane of the air inlet slot (7) are the right group. The left and right groups of metal sheets (21) are respectively connected to a left signal cable and a right signal cable, and the left signal cable and the right signal cable are electrically connected to the main controller (1).

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