Oil fume particle detector and online zero calibration method thereof

Abstract

The application discloses an oil fume particle detector, which comprises a shell, a box door rotatably connected to one side of the shell, a monitoring device arranged in the shell, an air suction pump, a filter, a first particle sensor, a water-air separator, a detection pipe for connecting the air suction pump, the filter, the first particle sensor and the water-air separator, and a display screen arranged on the box door, wherein the air suction pump, the filter, the first particle sensor and the water-air separator are arranged in the shell and fixedly connected with the shell, the first particle sensor is electrically connected with the display screen, one side of the water-air separator is provided with an air inlet pipe which is in communication with the inside of the water-air separator, and the oil fume particle content can be monitored in real time through the technical scheme.

Description

A particulate matter detector for cooking fumes and its online zeroing method Technical Field

[0001] This invention relates to the field of detection instrument technology, and in particular to an oil fume particulate matter detector and its online zeroing method. Background Technology

[0002] In modern society, with increasing environmental awareness and ever-improving air quality requirements, the detection of particulate matter from cooking fumes has become increasingly important. Particulate matter from cooking fumes not only harms human health, causing respiratory diseases, but also negatively impacts atmospheric quality. Therefore, accurate and reliable detection of the concentration and characteristics of particulate matter from cooking fumes is crucial for environmental protection and safeguarding human health.

[0003] However, traditional methods for detecting cooking fumes typically employ offline sampling and laboratory analysis. While these methods can obtain accurate data on fume concentration to a certain extent, they also have several significant drawbacks. First, offline sampling requires collecting airborne fume samples into containers and sending them to a laboratory for analysis. This process is not only time-consuming but also requires a lengthy preparation time, resulting in delayed results. Second, offline sampling usually requires professional personnel for sampling, processing, and transportation, making the process cumbersome and susceptible to interference from external factors. Furthermore, traditional detection methods often cannot monitor changes in particulate matter concentration in real time. This means that when fume concentrations are too high, necessary protective measures or effective emission control cannot be implemented in a timely manner, thus negatively impacting human health and the environment. Summary of the Invention

[0004] The main objective of this invention is to provide an oil fume particulate matter detector and its online zeroing method, which aims to monitor the content of oil fume particulate matter in real time.

[0005] To achieve the above objectives, the present invention proposes an oil fume particulate matter detector, comprising a housing, a door rotatably connected to one side of the housing, and a monitoring device inside the housing. The monitoring device includes an air pump, a filter, a first particulate matter sensor, a water-gas separator, a detection tube for connecting the air pump, filter, first particulate matter sensor, and water-gas separator, and a display screen mounted on the door. The air pump, filter, first particulate matter sensor, and water-gas separator are all disposed inside the housing and fixedly connected to the housing. The first particulate matter sensor is electrically connected to the display screen. An air inlet pipe is provided on one side of the water-gas separator and communicates with the interior of the water-gas separator.

[0006] In one possible implementation, the first particulate sensor has a detection cavity inside, and the detection tube communicates with the inside of the detection cavity.

[0007] It also includes a calibration component, which includes a filter membrane, a membrane cover, a capillary tube with one end connected to the inside of the detection chamber, and a solenoid valve on the detection tube between the first particulate sensor and the water-air separator. The first particulate sensor has a accommodating space on one side, and a cleaning air hole is provided on the side of the accommodating space. The other end of the capillary tube is connected to the cleaning air hole. The filter membrane and the membrane cover are arranged sequentially inside the accommodating space.

[0008] In one possible implementation, the housing further includes a backup monitoring component, which comprises a second particulate sensor with the same structure as the first particulate sensor, a first gas splitter, a backup tube, and a switching housing. The first gas splitter is disposed on a detection tube between the first particulate sensor and the filter. The switching housing is disposed on a detection tube between the first particulate sensor and the water-gas separator. One end of the backup tube is connected to the first gas splitter, and the other end of the backup tube is connected to the interior of the switching housing. The second particulate sensor is disposed on the backup tube and is electrically connected to the display screen. The switching housing contains a switching component for inputting gas into the first particulate sensor or into the second particulate sensor.

[0009] In one possible implementation, the switching assembly includes an electric push rod, an optical axis, and closed sections disposed on both sides of the optical axis. The switching housing has a flow cavity inside, and a detection chamber and a backup chamber are respectively disposed on both sides of the flow cavity. The flow cavity, the detection chamber, and the backup chamber are connected through a flow port. The inner diameter of the flow port is larger than the diameter of the optical axis and smaller than the diameter of the closed section. The detection tube and the backup tube are respectively connected to the detection chamber and the backup chamber. The detection tube on the water-air separator is connected to the interior of the flow cavity. The telescopic rod of the electric push rod is fixedly connected to one of the closed sections.

[0010] In one possible implementation, the flow port is provided with a first sealing slope on both sides near the spare chamber and the detection chamber, and a sealing gasket is provided in the first sealing slope. A second sealing slope that abuts against the sealing gasket is provided on the opposite side of the two closed sections.

[0011] The switching housing has a receiving groove on the side away from the electric push rod, and a first elastic element is provided inside the receiving groove. The other closed section is slidably connected to the inner wall of the receiving groove and abuts against the first elastic element.

[0012] In one possible implementation, an annular slide rail is fixedly connected inside the filter, and a rotating plate is rotatably connected inside the annular slide rail. The rotating plate is provided with a plurality of filter screens arranged circumferentially around the rotating plate. The detection tube inside the filter is divided into a detection tube one and a detection tube two, and the opposite sides of the detection tube one and the detection tube two respectively abut against the two sides of the rotating plate. The interiors of the detection tube one and the detection tube two are connected through the filter screens on the rotating plate. The filter is also provided with a rotating assembly that allows switching between the various filter screens.

[0013] In one possible implementation, a receiving block is fixedly connected to one side of each of the detection tubes. A sealing assembly is provided on the side of the receiving block near the rotating plate. The sealing assembly includes an annular sealing block, a sealing ring, and several second elastic elements. An annular groove is provided on the side of the receiving block near the rotating plate. One end of each second elastic element is fixedly connected to the side of the annular groove, and the other end of each second elastic element is fixedly connected to the annular sealing block. The annular sealing block is slidably connected to the inner wall of the annular groove. An annular groove is provided on the rotating plate near the periphery of each filter screen, and the sealing ring is disposed inside the annular groove. The annular sealing block abuts against the sealing ring. A first annular inclined surface is provided around the annular groove, and a second annular inclined surface is provided on the outer surface of the annular sealing block, which is slidably connected to the first annular inclined surface.

[0014] In one possible implementation, the rotating assembly includes a worm gear, a worm meshing with the worm gear, a micro motor, and a support plate. The support plate is fixedly connected to the inside of the filter. The worm gear is rotatably connected to the support plate via a rotating shaft, and the other end of the rotating shaft is fixedly connected to a rotating plate. A support block is fixedly connected to the top of the support plate. The worm is rotatably connected to the support block. The micro motor is fixed to the side of the support block, and the output end of the micro motor is fixedly connected to the worm.

[0015] In one possible implementation, the filter is further provided with an air jet assembly for cleaning particulate matter on the filter screen. The air jet assembly includes a second gas splitter, an air jet pipe, a discharge pipe, and a one-way valve. The second gas splitter is disposed on the detection pipe, and one end of the air jet pipe is connected to the interior of the second gas splitter. The other end of the air jet pipe abuts against the rotating plate, and the interior of the air jet pipe faces one of the filter screens. One side of the discharge pipe abuts against the rotating plate, and the position of the discharge pipe corresponds to the position of the air jet pipe. The one-way valve is disposed on the air jet pipe, and the outlet of the one-way valve faces the direction of the rotating plate.

[0016] The bottom of the filter is also provided with a collection assembly, which includes a collection shell and a partition plate. The inside of the collection shell is slidably connected to the outer surface of the filter, and the partition plate is fixedly connected to the inside of the filter. One side of the discharge pipe passes through the partition plate and extends into the inside of the collection shell. The bottom of the collection shell is provided with several screens, and the collection shell is fixedly connected to the filter by bolts.

[0017] To achieve online zeroing of oil fume particulate matter, this invention also provides an online zeroing method for an oil fume particulate matter detector. This method utilizes the aforementioned equipment and specifically includes the following steps:

[0018] S1. Close the solenoid valve on the detection tube between the first particulate matter sensor and the water-gas separator;

[0019] S2. Start the air pump;

[0020] S3. Observe the value of the particulate matter sensor on the display screen. When the value returns to zero, open the solenoid valve to continue the measurement.

[0021] This invention utilizes a monitoring device to sequentially pass oily fumes through an inlet pipe, a water-gas separator, a detection tube, a particulate matter sensor, a filter, and an air pump, forming a complete detection system to ensure accurate and reliable results. A display screen is located on the door for easy real-time viewing of data by operators. Compared to traditional offline sampling methods, this solution eliminates the need to send samples to a laboratory, enabling on-site testing, significantly reducing testing time and rapidly obtaining results. This allows users to monitor particulate matter concentration in oily fumes in real time, taking timely protective measures or implementing effective emission control to minimize negative impacts on human health and the environment.

[0022] In addition, the water-air separator can effectively remove moisture from the gas drawn in through the intake pipe, thereby improving the detection accuracy of the particulate matter sensor. Attached Figure Description

[0023] To more clearly illustrate the technical solutions in the embodiments of the present invention or the prior art, the drawings used in the description of the embodiments or the prior art will be briefly introduced below. Obviously, the drawings described below are only some embodiments of the present invention. For those skilled in the art, other drawings can be obtained based on the structures shown in these drawings without creative effort.

[0024] Figure 1 is a structural schematic diagram of this embodiment;

[0025] Figure 2 is a schematic diagram of the structure of the first particulate matter sensor in Embodiment 1;

[0026] Figure 3 is a partial structural exploded view of the first particulate matter sensor in Embodiment 1;

[0027] Figure 4 is a schematic diagram of the structure of this embodiment 2;

[0028] Figure 5 is a cross-sectional view of the switching shell in Embodiment 2;

[0029] Figure 6 is a partial cross-sectional view of the filter mechanism in Embodiment 3;

[0030] Figure 7 is an exploded view of the rotating plate and sealing assembly in Embodiment 3;

[0031] Figure 8 is a cross-sectional schematic diagram of the rotating plate, detection tube one, and detection tube two in Example 3;

[0032] Figure 9 is an enlarged view of point A in Figure 8;

[0033] Figure 10 is a schematic diagram of the rotating assembly structure in Embodiment 3;

[0034] Figure 11 is an exploded view of the filter and collection shell in Example 3.

[0035] Explanation of reference numerals: 1. Housing; 101. Door; 1011. Display screen; 102. Air pump; 103. Filter; 104. First particulate matter sensor; 105. Detection tube; 1051. Detection tube 1; 1052. Detection tube 2; 106. Water-air separator; 107. Air inlet pipe;

[0036] 2. Detection chamber; 201. Filter membrane; 202. Membrane cover; 203. Capillary tube; 204. Solenoid valve; 205. Accommodation space; 206. Cleaning vent;

[0037] 3. Second particulate matter sensor; 301. First gas splitter; 302. Spare tube; 303. Switching housing; 304. Electric push rod; 305. Optical axis; 306. Closed section; 307. Flow chamber; 308. Detection chamber; 309. Spare chamber; 310. Flow port; 312. First sealing slope; 313. Second sealing slope; 314. Receiving groove; 315. First elastic element;

[0038] 4. Annular slide rail; 401. Rotating plate; 402. Filter screen; 403. Receiving block; 404. Annular sealing block; 405. Second elastic element; 406. Sealing ring; 407. Annular receiving groove; 408. Annular groove; 409. First annular inclined surface; 410. Second annular inclined surface;

[0039] 5. Worm gear; 501. Worm; 502. Support plate; 503. Shaft; 504. Support block; 505. Miniature motor;

[0040] 6. Second gas distributor; 601. Jet pipe; 602. Discharge pipe; 603. Check valve; 604. Collection shell; 605. Divider plate; 606. Screen; 607. Bolt.

[0041] The realization of the objective, functional features and advantages of the present invention will be further explained in conjunction with the embodiments and with reference to the accompanying drawings. Detailed Implementation

[0042] To make the objectives, technical solutions, and advantages of this application clearer, the following detailed description is provided in conjunction with the accompanying drawings and embodiments. It should be understood that the specific embodiments described herein are merely illustrative and not intended to limit the scope of this application.

[0043] Example 1:

[0044] This invention proposes an oil fume particulate matter detector, referring to Figures 1-3. It includes a housing 1, with a door 101 rotatably connected to one side. A monitoring device is installed inside the housing 1, comprising an air pump 102, a filter 103, a first particulate matter sensor 104 (which can be an optical particulate matter sensor), a water-gas separator 106, a detection tube 105 connecting the air pump 102, filter 103, first particulate matter sensor 104, and water-gas separator 106, and a display screen 1011 mounted on the door 101. The air pump 102, filter 103, first particulate matter sensor 104, and water-gas separator 106 are all located inside the housing 1 and fixedly connected to it. Since oil fume gas may contain moisture, which can scatter light and affect the accurate measurement of scattered light from particulate matter, leading to an overestimation of the measured particulate matter concentration, this design incorporates a water-gas separator 106. It is worth noting that the main function of the water-gas separator 106 is to remove moisture (such as water vapor and water droplets) from the gas, but it cannot separate particulate matter in the gas.

[0045] The first particulate matter sensor 104 is electrically connected to the display screen 1011. An air inlet pipe 107 is provided on one side of the water-gas separator 106, and the air inlet pipe 107 is connected to the inside of the water-gas separator 106. An exhaust pipe is provided on the side of the air pump away from the detection pipe 105 for discharging filtered gas.

[0046] When the detector is in use, after the suction pump 102 is started, it generates negative pressure inside the detection tube 105 and the inlet pipe 107. Under the action of the external pressure difference, the oily fume gas enters the water-gas separator 106 through the inlet pipe 107. After passing through the water-gas separator 106, the liquid water is removed, and the separated flue gas enters the first particulate matter sensor 104 through the detection tube 105 for detection. The first particulate matter sensor 104 displays the detection result on the display screen 1011. The detected flue gas then enters the filter 103 through the detection tube 105 to remove oily fume particles, ensuring that the gas entering the air pump is clean and extending the service life of the air pump. Finally, the flue gas is discharged through the outlet pipe after passing through the air pump.

[0047] The monitoring system, consisting of an inlet pipe 107, a water-gas separator 106, a detection tube 105, a particulate matter sensor, a filter 103, and an air pump, forms a complete detection system, ensuring accurate and reliable test results. A display screen 1011 is mounted on the door 101 for easy real-time viewing of the data by operators. Compared to traditional offline sampling methods, this solution eliminates the need to send samples to a laboratory, enabling on-site testing, significantly reducing testing time and rapidly obtaining results. This allows users to monitor particulate matter concentration in the fumes in real time, take timely protective measures, or implement effective emission control, reducing negative impacts on human health and the environment.

[0048] In addition, the water-air separator 106 can effectively remove moisture from the gas drawn in by the air intake pipe 107, thereby improving the detection accuracy of the particulate matter sensor.

[0049] Furthermore, the first particulate matter sensor 104 has a detection cavity 2 inside, and the detection tube 105 is connected to the inside of the detection cavity 2. The detection cavity 2 also has an optical detection component for detecting particulate matter concentration, which typically includes a light emitter, a light trap, and a photodetector. The specific detection principle is a well-known prior art in the field, so it will not be described in detail here.

[0050] The system also includes calibration components, which include a filter membrane 201, a membrane cover plate 202, a capillary tube 203 with one end connected to the inside of the detection chamber 2, and a solenoid valve 204 disposed on the detection tube 105 between the first particulate sensor 104 and the water-air separator 106. A receiving space 205 is provided on one side of the first particulate sensor 104, and a cleaning air hole 206 is provided on the side of the receiving space 205. The other end of the capillary tube 203 is connected to the cleaning air hole 206. The filter membrane 201 and the membrane cover plate 202 are sequentially disposed inside the receiving space 205. The membrane cover plate 202 can be fixedly connected to the receiving space 205 by bolts 607 to ensure the secure fixation of the filter membrane 201. It should be noted that the capillary tube 203 can be made of polytetrafluoroethylene or silicone rubber.

[0051] When zeroing the first particulate matter sensor 104, the user closes the solenoid valve 204 on the detection tube 105 between the first particulate matter sensor 104 and the water-gas separator 106, and starts the vacuum pump 102. The vacuum pump 102 creates a negative pressure in the detection chamber 2 inside the first particulate matter sensor 104. Under the action of external atmospheric pressure, external gas passes through the filter membrane 201 and enters the cleaning pore 206, thereby allowing the gas to enter the detection chamber 2 through the capillary tube 203, blowing off the particulate matter adhering to the optical components inside the detection chamber 2, thus achieving zero-point self-calibration of the optical detection system. This zeroing method is simple to operate, effectively improves the accuracy of detection data, and avoids deviations in detection results caused by sensor zero-point drift.

[0052] The membrane can filter the gas entering the capillary tube 203, preventing secondary contamination of the optical components in the detection chamber 2, thereby reducing the time required for zeroing the first particulate sensor 104 and improving its practicality.

[0053] It is important to note that the side of the capillary tube 203 closest to the detection chamber 2 should be located at the edge of the detection chamber 2. This minimizes the dilution effect of the zeroing gas blown in from the capillary tube 203 on the concentration of contaminants within the detection area, thus reducing its impact on the detection results.

[0054] Meanwhile, to avoid this effect, a miniature solenoid valve can be installed on the capillary tube 203. When the particulate matter sensor detects the particulate matter content in the atmosphere, the miniature solenoid valve can be closed to ensure that no gas enters the capillary tube 203, thereby avoiding its impact on the sensor's detection effect. When zeroing, the miniature solenoid valve is opened.

[0055] Secondly, a main control board can be set on the outside of the housing 1, and the solenoid valve 204 and the miniature solenoid valve can be electrically connected to the main control board respectively, so that the user can control the opening and closing status of the two solenoid valves 204.

[0056] Example 2:

[0057] Based on Embodiment 1, and referring to Figures 4-5, this embodiment also includes a backup monitoring component inside the housing 1. The backup monitoring component includes a second particulate sensor 3 with the same structure as the first particulate sensor 104, a first gas splitter 301, a backup tube 302, and a switching housing 303. The first gas splitter 301 is located on the detection tube 105 between the first particulate sensor 104 and the filter 103. The switching housing 303 is located on the detection tube 105 between the first particulate sensor 104 and the water-gas separator 106. One end of the backup tube 302 is connected to the first gas splitter 301, and the other end of the backup tube 302 is connected to the inside of the switching housing 303. The second particulate sensor 3 is located on the backup tube 302 and is electrically connected to the display screen 1011. The switching housing 303 is equipped with a switching component for inputting gas into the first particulate sensor 104 or into the second particulate sensor 3.

[0058] The inclusion of a backup monitoring component significantly improves the reliability of the detector. When the first particulate sensor 104 malfunctions or requires maintenance, the gas can be introduced into the second particulate sensor 3 for detection by switching components, ensuring uninterrupted detection and providing continuous and reliable data support for environmental monitoring and production safety.

[0059] Specifically, the switching assembly includes an electric push rod 304, an optical axis 305, and closed sections 306 disposed on both sides of the optical axis 305. The switching housing 303 has a flow cavity 307 inside. The flow cavity 307 has a detection chamber 308 and a backup chamber 309 on both sides. The flow cavity 307, the detection chamber 308, and the backup chamber 309 are connected through a flow port 310. The inner diameter of the flow port 310 is larger than the diameter of the optical axis 305 and smaller than the diameter of the closed section 306. The detection tube 105 and the backup tube 302 are connected to the detection chamber 308 and the backup chamber 309, respectively. The detection tube 105 on the water-air separator 106 is connected to the inside of the flow cavity 307. The telescopic rod of the electric push rod 304 is fixedly connected to one of the closed sections 306.

[0060] When the second particulate sensor 3 is damaged or requires maintenance, the user can activate the electric push rod 304. The telescopic rod of the electric push rod 304 will simultaneously move the two closed sections 306 and the optical axis 305. Since the diameter of the closed section 306 is larger than the inner diameter of the flow port 310, the closed section 306 in the spare chamber 309 will directly seal the flow port 310, thereby preventing flue gas from entering the second particulate sensor 3 through the spare pipe 302. At the same time, the closed section 306 in the detection chamber 308 will move away from the flow port 310, connecting the flow chamber 307, the flow port 310, and the detection chamber 308, thus allowing flue gas to enter the first particulate sensor 104 for detection through the detection pipe 105. The switching assembly controls the movement of the optical axis 305 and the closed section 306 through the electric push rod 304 to achieve precise switching of gas between the first particulate sensor 104 and the second particulate sensor 3. Similarly, when the first particulate sensor 104 needs maintenance, the telescopic rod of the electric push rod 304 can be retracted.

[0061] Furthermore, the electric push rod 304 can also be electrically connected to the main control board for user operation. The switching mechanism can only allow flue gas to pass through one of the first particulate matter sensor 104 or the second particulate matter sensor 3; it cannot simultaneously supply flue gas to both sensors. That is, when the detection chamber 308 is open, the backup chamber 309 is closed; when the backup chamber 309 is open, the detection chamber 308 is closed.

[0062] When the vacuum pump 102 is working, it creates negative pressure inside both the backup tube 302 and the detection tube 105 simultaneously through the first gas distributor 301. When the switching mechanism closes the detection chamber 308, the gas will pass through the filter membrane 201 and enter the capillary tube 203 under external air pressure because the detection tube 105 on the first particulate sensor 104 is closed, automatically zeroing the first particulate sensor 104. When either the first particulate sensor 104 or the second particulate sensor 3 needs zeroing, the switching mechanism can be used to automatically zero one of the particulate sensors, thereby improving the system's practicality.

[0063] Secondly, a second solenoid valve can be installed on the detection tube 105 between the first particulate sensor 104 and the first gas splitter 301, and a third solenoid valve can be installed on the spare tube 302 between the second particulate sensor 3 and the first gas splitter 301. When zeroing of the first particulate sensor 104 or the second particulate sensor 3 is not required, and only maintenance or repair is needed, the corresponding second or third solenoid valve can be closed.

[0064] In this embodiment, a first sealing slope 312 is provided on both sides of the flow port 310 near the spare cavity 309 and the detection cavity 308 respectively, and a sealing gasket is provided in the first sealing slope 312. A second sealing slope 313 that abuts against the sealing gasket is provided on the opposite side of the two closed sections 306.

[0065] The inside of the switching housing 303 is provided with a receiving groove 314 on the side away from the electric push rod 304, and a first elastic member 315 is provided inside the receiving groove 314. Another closed section 306 is slidably connected to the inner wall of the receiving groove 314 and abuts against the first elastic member 315.

[0066] By setting the first sealing slope 312, the second sealing slope 313, and the sealing gasket, the contact area between the closed section 306 and the flow port 310 can be increased, ensuring a tight fit between the two, preventing gas leakage, and ensuring that the gas can enter the corresponding sensor along a predetermined path. At the same time, the first elastic element 315 can buffer the impact force generated when the electric push rod 304 extends, thereby ensuring the reliability and stability of the optical axis 305 and the closed section 306 during long-term use.

[0067] Example 3:

[0068] Based on Embodiment 1, referring to Figures 6-11, in this embodiment, an annular slide rail 4 is fixedly connected inside the filter 103, and a rotating plate 401 is rotatably connected inside the annular slide rail 4. The rotating plate 401 is provided with a plurality of filter screens 402 arranged circumferentially with the rotating plate 401 as the center. The detection tube 105 inside the filter 103 is divided into a detection tube 1051 and a detection tube 1052, and the opposite sides of the detection tube 1051 and the detection tube 1052 respectively abut against the two sides of the rotating plate 401. The interiors of the detection tube 1051 and the detection tube 1052 are connected through the filter screens 402 on the rotating plate 401. The filter 103 is also provided with a rotating assembly that allows switching between the various filter screens 402.

[0069] When a filter 402 becomes clogged, the rotating plate 401 is rotated by the rotating assembly, switching other clean filters 402 between detection tube 1051 and detection tube 1052, ensuring that the filter 103 continues to work normally without the need to manually replace the filter 402, reducing the time required to replace the filter 402, improving detection efficiency, and extending the service life of the filter 103.

[0070] Furthermore, a receiving block 403 is fixedly connected to the opposite side of the first detection tube 1051 and the second detection tube 1052. A sealing assembly is provided on the side of the receiving block 403 near the rotating plate 401. The sealing assembly includes an annular sealing block 404, a sealing ring 406, and several second elastic elements 405. An annular containing groove 407 is provided on the side of the receiving block 403 near the rotating plate 401. One end of each second elastic element 405 is fixedly connected to the side of the annular containing groove 407, and the other end of each second elastic element 405... All ends are fixedly connected to the annular sealing block 404, and the annular sealing block 404 is slidably connected to the inner wall of the annular placement groove 407. The rotating plate 401 is provided with annular grooves 408 near the periphery of each filter screen 402, and the sealing ring 406 is disposed inside the annular groove 408. The annular sealing block 404 abuts against the sealing ring 406. The periphery of the annular groove 408 is provided with a first annular inclined surface 409, and the outer surface of the annular sealing block 404 is provided with a second annular inclined surface 410 that is slidably connected to the first annular inclined surface 409.

[0071] When the filter 402 between the detection tube 1051 and the detection tube 1052 becomes clogged, the user can rotate the rotating plate 401 by rotating the rotating assembly. At the same time, the first annular inclined surface 409 around the annular groove 408 presses the second annular inclined surface 410 on the annular sealing block 404, causing it to gradually move in the direction of compressing the second elastic element 405 until it is completely removed from the interior of the annular groove 408.

[0072] When the changing groove of the next filter screen 402 aligns with the annular sealing block 404, the annular sealing block 404 engages with the annular groove 408 under the action of multiple second elastic elements 405 and contacts the sealing ring 406. Because the second elastic elements 405 have the ability to recover their deformation, they ensure that the annular sealing block 404 remains in contact with the sealing ring 406, thereby improving the sealing between the first detection tube 1051, the second detection tube 1052, and the rotating plate 401, reducing the possibility of gas leakage, and ensuring the filtration efficiency of the filter screen 402.

[0073] When replacing the filter 402, simply rotate the assembly to overcome the elastic force of multiple second elastic elements 405 to complete the replacement, avoiding complicated operations and thus improving the convenience of operation.

[0074] In this embodiment, the sealing components are placed on the receiving block 403 instead of in each annular groove 408 on the rotating plate 401 in order to reduce the number of sealing components and thus reduce manufacturing costs.

[0075] Specifically, the rotating assembly includes a worm gear 5, a worm 501 meshing with the worm gear 5, a micro motor 505, and a support plate 502. The support plate 502 is fixedly connected to the inside of the filter 103. The worm gear 5 is rotatably connected to the support plate 502 via a rotating shaft 503, and the other end of the rotating shaft 503 is fixedly connected to a rotating plate 401. A support block 504 is fixedly connected to the top of the support plate 502. The worm 501 is rotatably connected to the support block 504. The micro motor 505 is fixed to the side of the support block 504, and the output end of the micro motor 505 is fixedly connected to the worm 501.

[0076] The rotating assembly employs a combination of a worm gear 5, a worm 501, and a micro motor 505 to achieve automated control of the filter 402 switching. The micro motor 505 drives the worm gear 5 to rotate via the worm 501, which in turn drives the rotating plate 401 to rotate. Simultaneously, the worm gear 5 and worm 501 transmission can provide a large torque so that the rotating plate 401 can press the annular sealing block 404 into the annular positioning groove 407.

[0077] In this embodiment, an air jet assembly for cleaning particles on the filter screen 402 is also provided inside the filter 103. The air jet assembly includes a second gas splitter 6, an air jet pipe 601, a discharge pipe 602, and a one-way valve 603. The second gas splitter 6 is installed on the detection tube 1052, and one end of the air jet pipe 601 is connected to the inside of the second gas splitter 6. The other end of the air jet pipe 601 abuts against the rotating plate 401, and the inside of the air jet pipe 601 faces one of the filter screens 402. One side of the discharge pipe 602 abuts against the rotating plate 401, and the position of the discharge pipe 602 corresponds to the position of the air jet pipe 601. The one-way valve 603 is installed on the air jet pipe 601, and the outlet of the one-way valve 603 faces the rotating plate 401. The purpose of setting the one-way valve 603 is to avoid negative pressure inside the air jet pipe 601 and ensure that the air jet pipe 601 can only blow air.

[0078] The bottom of the filter 103 is also provided with a collection assembly, which includes a collection shell 604 and a partition plate 605. The inside of the collection shell 604 is slidably connected to the outer surface of the filter 103, and the partition plate 605 is fixedly connected to the inside of the filter 103. One side of the discharge pipe 602 passes through the partition plate 605 and extends into the inside of the collection shell 604. The bottom of the collection shell 604 is provided with several screens 606. The collection shell 604 is fixedly connected to the filter 103 by bolts 607.

[0079] The air jet pipe 601 cleans particulate matter from the filter screen 402. Air is sprayed through the air jet pipe 601 onto the filter screen 402, blowing off the particulate matter, which then enters the collection assembly through the discharge pipe 602. The collection housing 604 and screen 606 in the collection assembly effectively collect particulate matter. The pores on the screen 606 ensure that gas can be discharged from the interior of the filter 103. The collection housing 604 is connected to the filter 103 by bolts 607 to facilitate user disassembly of the collection housing 604 for cleaning the internal particulate matter.

[0080] The specific principle is as follows:

[0081] When the air pump 102 is working, it will generate negative pressure inside the second gas distributor 6, the detection tube 105, the first particulate sensor 104, and the air inlet pipe 107. However, due to the presence of the one-way valve 603, the jet pipe 601 cannot generate negative pressure. The oil fume gas will enter the detection tube 1051 of the filter 103 through the detection tube 105 and enter the detection tube 1052 through the filter screen 402. The particulate matter will adhere to the surface of the filter screen 402. When the gas enters the second gas distributor 6, the filtered oil fume gas will be divided into two airflows. One airflow enters the air pump through the detection tube 1052 and is discharged through the exhaust pipe. The other airflow will be sprayed onto the surface of the filter screen 402 through the jet pipe 601, so that the particulate matter attached to the side of the filter screen 402 away from the jet pipe 601 will fall into the collection shell 604 through the discharge pipe 602.

[0082] The jet assembly in this embodiment does not require an external air source, meaning that the detector does not need complex air source access pipes or other related components inside. This greatly simplifies the overall structure of the device, making the detector smaller and reducing costs.

[0083] Secondly, the reverse airflow directly impacts the particles adhering to the filter screen 402, using the reverse impact force of the airflow to blow the particles out of the pores of the filter screen 402. Compared to forward airflow, reverse airflow can more effectively loosen and remove stubborn particles adhering to the inside of the filter screen 402, improving cleaning efficiency and ensuring that the filtration performance of the filter screen 402 is maintained continuously.

[0084] Furthermore, unlike traditional methods that require manual cleaning or replacement of filter 402, this air-jet cleaning method can be performed during normal equipment operation without stopping the machine to remove filter 402. This significantly saves cleaning time and improves testing efficiency.

[0085] Example 4:

[0086] Based on Example 1, this example proposes an online zeroing method for an oil fume particulate matter detector, which specifically includes the following steps:

[0087] S1. Close the solenoid valve 204 on the detection tube 105 between the first particulate matter sensor 104 and the water-gas separator 106.

[0088] S2. Start the air pump 102;

[0089] S3. Observe the value of the particulate matter sensor on the display screen 1011. When the value returns to zero, open the solenoid valve 204 to continue the measurement.

[0090] In the accompanying drawings of this embodiment, the same or similar reference numerals correspond to the same or similar components. In the description of this application, it should be understood that if terms such as "upper," "lower," "left," "right," etc., indicate the orientation or positional relationship based on the orientation or positional relationship shown in the accompanying drawings, they are only for the convenience of describing this application and simplifying the description, and do not indicate or imply that the device or element referred to must have a specific orientation, or be constructed and operated in a specific orientation. Therefore, the terms used to describe positional relationships in the accompanying drawings are only for illustrative purposes and should not be construed as limiting this patent. For those skilled in the art, the specific meaning of the above terms can be understood according to the specific circumstances.

[0091] The above are merely preferred embodiments of this application and are not intended to limit this application. Any modifications, equivalent substitutions, and improvements made within the spirit and principles of this application should be included within the protection scope of this application.

Claims

1. A particulate matter detector for cooking fumes, comprising a housing (1), wherein a door (101) is rotatably connected to one side of the housing (1), characterized in that: The housing (1) is equipped with a monitoring device, which includes an air pump (102), a filter (103), a first particulate matter sensor (104), a water-gas separator (106), a detection tube (105) for connecting the air pump (102), the filter (103), the first particulate matter sensor (104), and the water-gas separator (106), and a display screen (1011) installed on the door (101). The air pump (102), the filter (103), the first particulate matter sensor (104), and the water-gas separator (106) are all installed inside the housing (1) and are fixedly connected to the housing (1). The first particulate sensor (104) is electrically connected to the display screen (1011). An air inlet pipe (107) is provided on one side of the water-air separator (106), and the air inlet pipe (107) communicates with the interior of the water-air separator (106). An annular slide rail (4) is fixedly connected inside the filter (103). A rotating plate (401) is rotatably connected inside the annular slide rail (4). Several filter screens (402) are arranged circumferentially around the rotating plate (401). The detection tube (105) inside the filter (103) is divided into a detection tube one (1051) and a detection tube two (1052). 1052), and the opposite sides of the detection tube (1051) and the detection tube (1052) respectively abut against the two sides of the rotating plate (401). The interiors of the detection tube (1051) and the detection tube (1052) are connected through the filter screen (402) on the rotating plate (401). The filter (103) is also provided with a rotating assembly for switching between the various filter screens (402). The filter (103) is also provided with an air jet assembly for cleaning particles on the filter screen (402). The air jet assembly includes a second gas splitter (6), an air jet pipe (601), a discharge pipe (602), and a one-way valve (602). 603), the second gas splitter (6) is set on the detection tube (1052), and one end of the jet pipe (601) is connected to the inside of the second gas splitter (6), the other end of the jet pipe (601) is in contact with the rotating plate (401), and the inside of the jet pipe (601) faces one of the filters (402), one side of the discharge pipe (602) is in contact with the rotating plate (401), and the position of the discharge pipe (602) corresponds to the position of the jet pipe (601), the one-way valve (603) is set on the jet pipe (601), and the outlet of the one-way valve (603) faces the rotating plate (401);The bottom of the filter (103) is also provided with a collection assembly, which includes a collection shell (604) and a partition plate (605). The inside of the collection shell (604) is slidably connected to the outer surface of the filter (103), and the partition plate (605) is fixedly connected to the inside of the filter (103). One side of the discharge pipe (602) passes through the partition plate (605) and extends into the inside of the collection shell (604). The bottom of the collection shell (604) is provided with several screens (606). The collection shell (604) is fixedly connected to the filter (103) by bolts (607).

2. The oil fume particulate matter detector according to claim 1, characterized in that: The first particulate sensor (104) has a detection chamber (2) inside, and the detection tube (105) is connected to the inside of the detection chamber (2); it also includes a calibration component, which includes a filter membrane (201), a membrane cover plate (202), a capillary tube (203) with one end connected to the inside of the detection chamber (2), and a solenoid valve (204) set on the detection tube (105) between the first particulate sensor (104) and the water-air separator (106). The first particulate sensor (104) has a accommodating space (205) on one side, and a cleaning vent (206) is provided on the side of the accommodating space (205). The other end of the capillary tube (203) is connected to the cleaning vent (206). The filter membrane (201) and the membrane cover plate (202) are arranged in sequence inside the accommodating space (205).

3. The oil fume particulate matter detector according to claim 2, characterized in that: The housing (1) is also equipped with a backup monitoring component, which includes a second particulate sensor (3) with the same structure as the first particulate sensor (104), a first gas splitter (301), a backup tube (302), and a switching shell (303). The first gas splitter (301) is located on the detection tube (105) between the first particulate sensor (104) and the filter (103), and the switching shell (303) is located between the first particulate sensor (104) and the water-gas separator (106). On the detection tube (105) between, one end of the spare tube (302) is connected to the first gas splitter (301), and the other end of the spare tube (302) is connected to the inside of the switching housing (303). The second particulate sensor (3) is installed on the spare tube (302) and is electrically connected to the display screen (1011). The switching housing (303) is provided with a switching component for inputting gas into the first particulate sensor (104) or into the second particulate sensor (3).

4. The oil fume particulate matter detector according to claim 3, characterized in that: The switching assembly includes an electric push rod (304), an optical axis (305), and closed sections (306) arranged on both sides of the optical axis (305). The switching housing (303) has a flow chamber (307) inside. The flow chamber (307) has a detection chamber (2) and a spare chamber (309) on both sides. The flow chamber (307), detection chamber (2), and spare chamber (309) are connected through a flow port (310). The inner diameter of the flow port (310) is larger than the diameter of the optical axis (305) and smaller than the diameter of the closed section (306). The detection tube (105) and the spare tube (302) are connected to the detection chamber (2) and the spare chamber (309) respectively. The detection tube (105) on the water-air separator (106) is connected to the inside of the flow chamber (307). The telescopic rod of the electric push rod (304) is fixedly connected to one of the closed sections (306).

5. The oil fume particulate matter detector according to claim 4, characterized in that: The flow port (310) is provided with a first sealing slope (312) on both sides near the spare chamber (309) and the detection chamber (2), and a sealing gasket is provided in the first sealing slope (312). The two closed sections (306) are provided with a second sealing slope (313) on the opposite side that abuts against the sealing gasket. The switching shell (303) is provided with a receiving groove (314) on the side away from the electric push rod (304), and a first elastic element (315) is provided in the receiving groove (314). The other closed section (306) is slidably connected to the inner wall of the receiving groove (314) and abuts against the first elastic element (315).

6. The oil fume particulate matter detector according to claim 4, characterized in that: Each of the detection tubes (1051) and (1052) has a fixedly connected receiving block (403) on one side. A sealing assembly is provided on the side of the receiving block (403) near the rotating plate (401). The sealing assembly includes an annular sealing block (404), a sealing ring (406), and several second elastic elements (405). An annular receiving groove (407) is provided on the side of the receiving block (403) near the rotating plate (401). One end of each second elastic element (405) is fixedly connected to the side of the annular receiving groove (407), and the other end of each second elastic element (405) is... The annular sealing block (404) is fixedly connected to the annular sealing block (404), and the annular sealing block (404) is slidably connected to the inner wall of the annular placement groove (407). The rotating plate (401) is provided with annular grooves (408) near the periphery of each filter screen (402), and the sealing ring (406) is disposed inside the annular groove (408). The annular sealing block (404) abuts against the sealing ring (406). The periphery of the annular groove (408) is provided with a first annular inclined surface (409), and the outer surface of the annular sealing block (404) is provided with a second annular inclined surface (410) that is slidably connected to the first annular inclined surface (409).

7. The particulate matter detector for cooking fumes according to claim 1, characterized in that: The rotating assembly includes a worm gear (5), a worm (501) meshing with the worm gear (5), a micro motor (505), and a support plate (502). The support plate (502) is fixedly connected to the inside of the filter (103). The worm gear (5) is rotatably connected to the support plate (502) through a rotating shaft (503), and the other end of the rotating shaft (503) is fixedly connected to a rotating plate (401). A support block (504) is fixedly connected to the top of the support plate (502). The worm (501) is rotatably connected to the support block (504). The micro motor (505) is fixed to the side of the support block (504), and the output end of the micro motor (505) is fixedly connected to the worm (501).

8. An online zeroing method for an oil fume particulate matter detector, comprising the oil fume particulate matter detector as described in any one of claims 1 to 7, characterized in that: Specifically, the following steps are included: S1. Close the solenoid valve (204) on the detection tube (105) between the first particulate matter sensor (104) and the water-air separator (106); S2. Start the air pump (102); S3. Observe the value of the particulate matter sensor on the display screen (1011). When the value returns to zero, open the solenoid valve (204) to continue the measurement.

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