Passive explosive detector

Abstract

The invention provides a passive explosive detector, the passive explosive detector comprises a machine body, a heating head assembly, a detection assembly, a ventilation pipe and a rotational flow part, the heating head assembly is arranged at one end of the machine body, a heating cavity is formed in the heating head assembly, the detection assembly is arranged in the machine body, and the ventilation pipe is arranged in the machine body. An air inlet channel and an air outlet channel are formed in the ventilation pipe, the air inlet channel is communicated with the heating cavity and the outside, and the air outlet channel is communicated with the heating cavity and the detection assembly; the rotational flow component is located in the air inlet channel or located between the air inlet channel and the heating cavity. The passive explosive detector provided by the embodiment of the invention has the advantage of accurate detection result.

Description

Technical Field

[0001] The present invention relates to the technical field of explosive detectors, and in particular to a passive explosive detector. Background Art

[0002] Explosives detectors are commonly used in the security inspection field, and are considered one of the three major security inspection products, along with X-ray security inspection machines and walk-through security gates. These detectors primarily rely on ion mobility spectrometry technology to efficiently detect and identify explosive gas molecules. Ion mobility spectrometry is an effective method for rapidly analyzing trace amounts of chemical substances, particularly suitable for detecting dangerous goods such as explosives and drugs. This technology measures the migration behavior of ions in a sample in an electric field, enabling qualitative and quantitative analysis of substances based on the differences in the mobility of different ions under specific electric fields. Passive explosives detectors utilize this principle, integrating multiple functional modules such as detection and analysis, identification and alarm, and human-computer interaction, to provide an efficient and accurate security inspection method.

[0003] However, in actual application, when the detector is running, on the one hand, the explosive gas molecules are unevenly distributed, and on the other hand, the detector is easily disturbed by vibration factors, which affects the accuracy and reliability of the detection results. Summary of the Invention

[0004] The present invention provides a passive explosive detector, which is used to solve the problems in the prior art that explosive gas is unevenly distributed during operation of the passive explosive detector and the detection result is easily affected by vibration factors.

[0005] The present invention provides a passive explosive detector, comprising: body; A heating head assembly is provided at one end of the body, and a heating cavity is formed in the heating head assembly; A detection component is disposed within the body; A ventilation duct, wherein an air inlet duct and an air outlet duct are formed inside the duct, wherein the air inlet duct connects the heating chamber with the outside, and the air outlet duct connects the heating chamber with the detection component; The swirl component is located in the air inlet duct, or between the air inlet duct and the heating chamber.

[0006] In some embodiments, the air inlet duct surrounds the outer periphery of the air outlet duct, a blower is provided at one end of the air inlet duct away from the heating chamber, and an exhaust fan is provided at one end of the detection component away from the air outlet duct.

[0007] In some embodiments, the swirl component comprises: An air guide member, wherein the air guide member is formed with a vent and an air guide cavity, the vent is connected to the air inlet duct, and the air guide cavity is connected to the heating cavity; A plurality of blades are distributed at intervals on the periphery of the vent and are used to guide the airflow at the vent to the periphery of the vent and into the air guide cavity.

[0008] In some embodiments, the inner wall surface of the air guide comprises: a tapered surface, wherein the inner diameter of the tapered surface gradually increases in a direction from the ventilation tube to the heating head assembly; an annular surface connected to an end of the conical surface facing away from the ventilation pipe; The blades are used to guide the airflow at the vent toward the conical surface.

[0009] In some embodiments, an annular groove is provided on the air guide member corresponding to the vent, the blade is installed in the annular groove, an annular baffle is provided on the side of the blade facing away from the ventilation pipe, and the air outlet duct passes through the vent and the annular baffle.

[0010] In some embodiments, the outlet of the detection component is connected to the inlet of the exhaust fan through a connecting pipe, and the connecting pipe is a flexible pipe.

[0011] In some embodiments, the inner diameter of at least a portion of the connecting pipe gradually increases along a direction from the detection component to the exhaust fan.

[0012] In some embodiments, the passive explosives detector comprises: A plurality of support members, clamped with the ventilation pipe; The shock-absorbing member is provided in a one-to-one correspondence with the plurality of supporting members, and the shock-absorbing member is provided between the supporting member and the ventilation pipe.

[0013] In some embodiments, a plurality of the support members are arranged at intervals, a groove is provided on the outer peripheral surface of the ventilation pipe and one of the surfaces of the support member, a protrusion is provided on the outer peripheral surface of the ventilation pipe and one of the surfaces of the support member, and the protrusion extends into the groove.

[0014] In some embodiments, the passive explosives detector comprises: A flow guide member is provided in the air guide cavity, and the flow guide member is formed with a flow guide port and a flow guide cavity, the flow guide port is connected to the inlet of the air outlet duct, and the flow guide cavity is connected to the heating cavity.

[0015] First, the passive explosive detector of the embodiment of the present invention is provided with a swirl component, so that the external airflow is forced to form a swirl before entering the heating chamber, thereby significantly enhancing the disturbance effect of the airflow in the heating chamber, so that the objects to be detected in the heating chamber can be more evenly distributed in the airflow after being heated and volatilized, avoiding sampling deviations caused by local uneven concentrations.

[0016] Secondly, the passive explosive detector of the embodiment of the present invention allows the swirl flow to be introduced into the heating chamber, and can also improve the mixing efficiency between the molecules of the object to be detected and the airflow under the premise of the same sample volatility concentration, thereby increasing the number of molecules of the object to be detected entering the detection component per unit time, thereby improving the detection sensitivity and the accuracy of the results, ensuring that the passive explosive detector can maintain high-precision detection capabilities.

[0017] In addition, since swirl can smooth the airflow path and reduce the occurrence of turbulence, the airflow is more orderly and stable, which also helps to reduce unnecessary vibration, thereby reducing the impact of vibration on the detection components and improving the accuracy of the detection results. BRIEF DESCRIPTION OF THE DRAWINGS

[0018] In order to more clearly illustrate the technical solutions in the present invention or the prior art, a brief introduction is given below to the drawings required for use in the embodiments or the description of the prior art. Obviously, the drawings described below are some embodiments of the present invention. For ordinary technicians in this field, other drawings can be obtained based on these drawings without paying any creative work.

[0019] Figure 1 It is a schematic diagram of the half-section structure of the passive explosive detector provided by the present invention.

[0020] Figure 2 It is a structural schematic diagram of the passive explosive detector provided by the present invention.

[0021] Figure 3 The figure is a schematic diagram of the installation of the support member and the connecting pipe of the passive explosive detector provided by the present invention.

[0022] Figure 4 It is a structural schematic diagram of the swirl component of the passive explosive detector provided by the present invention.

[0023] Figure 5 It is a schematic diagram of the half-section structure of the swirl component of the passive explosive detector provided by the present invention.

[0024] Figure 6 It is a structural schematic diagram of the blades and annular baffle of the passive explosive detector provided by the present invention.

[0025] Figure 7 The diagram is a structural diagram of an air guide member of a passive explosive detector provided by the present invention.

[0026] Figure 8 The diagram is a structural diagram of a swirl component and a flow guide member of a passive explosive detector provided by the present invention.

[0027] Figure 9 This is a gas flow path diagram of the passive explosive detector provided by the present invention.

[0028] Reference numerals: 100. Passive explosive detector; 1. Machine body; 2. Heating head assembly; 21. Heating chamber; 3. Detection assembly; 4. Ventilation duct; 41. Air inlet duct; 42. Air outlet duct; 5. Swirl component; 51. Air guide; 511. Ventilation port; 512. Air guide cavity; 513. Annular groove; 514. Conical surface; 515. Annular surface; 52. Blade; 53. Annular baffle; 6. Blower; 7. Exhaust fan; 8. Connecting pipe; 9. Support; 10. Flow guide; 11. Flow guide port; 12. Flow guide cavity; 13. Return air component; 130. First air inlet; 131. Return air outlet; 132. Return air chamber; 133. Return air switch; 14. Second air inlet. DETAILED DESCRIPTION

[0029] To make the objectives, technical solutions, and advantages of the present invention more clear, the technical solutions of the present invention will be clearly and completely described below in conjunction with the accompanying drawings. Obviously, the embodiments described are only some of the embodiments of the present invention, not all of them. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without making creative efforts shall fall within the scope of protection of the present invention.

[0030] like Figures 1 to 9 As shown, the passive explosive detector 100 according to the embodiment of the present invention includes a body 1 , a heating head assembly 2 , a detection assembly 3 , a ventilation pipe 4 and a swirl component 5 .

[0031] The heating head assembly 2 is disposed at one end of the body 1 , and a heating cavity 21 is formed in the heating head assembly 2 .

[0032] The detection component 3 is arranged in the body 1 .

[0033] An air inlet duct 41 and an air outlet duct 42 are formed inside the ventilation pipe 4 . The air inlet duct 41 connects the heating chamber 21 with the outside, and the air outlet duct 42 connects the heating chamber 21 with the detection component 3 .

[0034] The swirl component 5 is located in the air inlet duct 41 , or between the air inlet duct 41 and the heating chamber 21 .

[0035] For the convenience of description, the left and right directions are taken as the extending directions of the body 1, wherein the left and right directions are as follows: Figure 1 shown.

[0036] The heating head assembly 2 is arranged at the left end of the body 1, and a heating chamber 21 is provided inside the heating head assembly 2 for accommodating the sample and heating and burning it. The heating head assembly 2 includes an end cover and a heating element. The end cover is opened to allow the sample to be placed in the heating chamber 21, and the heating element is used to ignite the sample.

[0037] The external airflow enters the heating chamber 21 through the air inlet duct 41 in the ventilation pipe 4, and is fully mixed with the object to be detected after combustion in the heating chamber 21 to form a high-temperature airflow carrying the molecules of the object to be detected. The high-temperature airflow is then transported to the detection component 3 through the air outlet duct 42. The detection component 3 analyzes and identifies the components of the molecules of the object to be detected carried in the airflow to realize the detection of the sample components.

[0038] Detection component 3's detection principle is based on ion mobility spectrometry. This technology is a highly sensitive detection method that uses differences in ion mobility between different substances in an electric field to analyze their composition. Its operating process primarily involves the following: After the gas to be tested enters detection component 3, the ionization source ionizes the molecules within it into charged particles. Under the influence of a uniform electric field, these ions migrate toward the electrodes at speeds related to their mass and shape. Because the ion mobility of different substances varies, they arrive at the detector at different times, forming a characteristic migration spectrum. By comparing the migration times of known substances against a database, target molecules such as explosives can be rapidly identified and determined in the sample being tested. Ion mobility spectrometry offers advantages such as fast response, high sensitivity, and the absence of a complex vacuum system, making it particularly suitable for on-site detection of trace explosives.

[0039] During this process, the swirl component 5 is arranged inside the air inlet duct 41, or located at the connection between the air inlet duct 41 and the heating chamber 21, so that the airflow entering from the air inlet duct 41 is guided into a rotating flow state when passing through the swirl component 5.

[0040] First, the passive explosive detector 100 provided in the embodiment of the present invention is provided with a swirl component 5, so that the external airflow is forced to be guided to form a rotating flow state before entering the heating chamber 21, which is the so-called "swirl". The formation of this swirl not only changes the original relatively straight motion trajectory of the airflow, but also significantly enhances the disturbance effect of the airflow inside the heating chamber 21. Since the swirl has a strong lateral diffusion ability, it can effectively destroy the boundary layer that may be formed near the wall surface of the heating chamber 21, thereby promoting the molecules released by the object to be detected after being heated to be more quickly and evenly distributed in the entire airflow. In this way, the sampling deviation problem caused by local uneven concentration is avoided, providing a more stable and reliable gas sample basis for the subsequent detection process.

[0041] Secondly, in the embodiment of the present invention, the introduction of swirl into the interior of the heating chamber 21 not only improves the fluidity of the airflow itself, but more importantly, under the premise of the same sample volatile concentration, significantly improves the mixing efficiency between the molecules of the object to be detected and the airflow. Specifically, the strong disturbance effect brought by the swirl greatly increases the heat and mass transfer rate in the airflow, thereby accelerating the volatilization rate of the target substance in the sample and enhancing its diffusion ability in the airflow. This efficient mixing process directly leads to a significant increase in the number of molecules of the object to be detected entering the detection component 3 per unit time, which is manifested macroscopically as an increase in the detection signal intensity and a shortening of the response time. This not only helps to improve the sensitivity of the detection, but also further guarantees the accuracy and repeatability of the detection results, so that the passive explosive detector 100 can still maintain high detection accuracy and stability under complex environmental conditions.

[0042] In addition, from the perspective of airflow dynamics, the flow path of swirl is more orderly and smooth than that of ordinary turbulent airflow. This smooth airflow state reduces to a certain extent the unstable phenomena such as local vortex and backflow that may occur during the operation of the airflow inside the equipment, thereby effectively reducing the mechanical vibration caused by the turbulent airflow inside the system. Especially for high-precision analysis modules such as the detection component 3, any tiny mechanical vibration may interfere with the detection signal and affect the final judgment result. Therefore, by providing the swirl component 5, not only the flow state of the airflow is optimized, but also the effect of shock absorption and noise reduction is objectively achieved, further reducing the impact of vibration on the detection component 3.

[0043] Therefore, the passive explosive detector 100 of the embodiment of the present invention has significant advantages such as accurate detection results, high sensitivity, and fast response speed, and has good application prospects and promotion value.

[0044] In some embodiments, as Figure 1 As shown, the air inlet duct 41 surrounds the outer periphery of the air outlet duct 42 , and a blower 6 is provided at one end of the air inlet duct 41 away from the heating chamber 21 , and an exhaust fan 7 is provided at one end of the detection component 3 away from the air outlet duct 42 .

[0045] The ventilation duct 4 includes an inner tube and an outer tube. The inner tube is inserted into the outer tube. The inner peripheral wall of the inner tube defines an air outlet duct 42. The outer peripheral wall of the inner tube and the inner peripheral wall of the outer tube define an air inlet duct 41. The air inlet duct 41 surrounds the outer periphery of the air outlet duct 42, forming a nested air duct design. This design not only optimizes the internal space layout of the equipment, but also improves the compactness and efficiency of the air flow path.

[0046] For ease of description, Figure 1 The up and down directions are marked in FIG. The blower 6 and the exhaust fan 7 are both arranged below the ventilation pipe 4.

[0047] A blower 6 is provided at one end of the air inlet duct 41 away from the heating chamber 21, that is, a blower 6 is provided at the right end of the air inlet duct 41, and the blower 6 is used to force the outside air into the heating chamber 21; The detection component 3 is arranged at the right end of the air outlet duct 42, and an exhaust fan 7 is provided at the end of the detection component 3 away from the air outlet duct 42, that is, the exhaust fan 7 is provided at the right end of the detection component 3. The exhaust fan 7 can ensure that the high-temperature airflow containing the molecules of the object to be detected coming out of the heating chamber 21 can be effectively extracted and transported to the detection component 3 through the air outlet duct 42.

[0048] The passive explosive detector 100 of the embodiment of the present invention introduces a coordinated driving mechanism of the blower 6 and the exhaust fan 7 in its overall structural design, thereby significantly enhancing the flow performance and flow speed of the airflow during the entire detection process. Through this design, fresh air from the outside can be introduced into the interior of the device at a higher pressure and a more stable flow rate, and fully mixed with the substance to be detected that is volatilized after being heated in the heating chamber 21. This enhanced gas flowability not only improves the diffusion efficiency of the sample molecules in the airflow, but also ensures that the mixed gas can be transported to the detection component 3 in a shorter time and in a more uniform state, providing a high-quality gaseous sample for subsequent component analysis. Compared with the traditional structure that relies on natural convection or a single airflow drive, this solution effectively overcomes the problems of gas transmission lag and uneven mixing through the active control strategy of the dual fans, further improving the detection response speed and data accuracy.

[0049] Moreover, in the embodiment of the present invention, by providing a blower 6 and an exhaust fan 7, and on this basis, combined with the optimization effect of the swirl component 5 on the airflow morphology, the three form a synergistic effect: the blower 6 provides a stable and continuous air inlet airflow, the exhaust fan 7 maintains the negative pressure environment at the air outlet, and the swirl component 5 guides the direction of the airflow, so that the air before entering the heating chamber 21 forms a rotating flow state. This rotating airflow has a stronger disturbance ability, which helps to improve the uniformity of the distribution of the molecules of the object to be detected in the airflow, and can also effectively reduce the turbulence caused by sudden changes in the airflow and disordered direction. As a result, not only the overall efficiency of gas transmission is improved, but also the mechanical vibration problem caused by unstable airflow is greatly reduced.

[0050] Due to the stable airflow environment formed by the combined action of the blower 6, the exhaust fan 7 and the swirl component 5, the internal vibration of the passive explosive detector 100 is significantly reduced during operation, thereby reducing the interference that these vibrations may cause to the detection component 3. Especially when the detection component 3 adopts high-sensitivity ion mobility spectrometry technology, even tiny mechanical vibrations may cause signal drift or misjudgment. Therefore, by optimizing the airflow path and suppressing the generation of vibrations, the present invention effectively ensures that the detection component 3 operates in a stable environment, thereby further improving the accuracy and repeatability of the detection results. In some embodiments, such as Figures 4 to 8 As shown, the swirl component 5 includes an air guide 51 and a plurality of blades 52. The air guide 51 is formed with a vent 511 and an air guide cavity 512. The vent 511 is connected to the air inlet duct 41, and the air guide cavity 512 is connected to the heating chamber 21. The plurality of blades 52 are spaced apart around the vent 511 to guide the airflow at the vent 511 to the surrounding areas of the vent 511 and into the air guide cavity 512.

[0051] A plurality of blades 52 are arranged in a sequentially spaced arrangement around the outer circumference of the vent 511, and the blades 52 are arranged at an angle to facilitate the generation of swirl. The number of blades 52 can be set according to actual needs and is not limited here.

[0052] After entering the air inlet duct 41, the external airflow enters the air guide cavity 512 through the vent 511, and then flows to the heating cavity 21. The blades 52 guide the external airflow entering through the vent 511 in all directions, so that it enters the air guide cavity 512 in a rotating manner, thereby forming a vortex.

[0053] The passive explosive detector 100 of the embodiment of the present invention is provided with a plurality of blades 52 arranged in an inclined manner at the vent 511. These blades 52 are arranged according to a certain angle and distribution pattern, and can effectively guide the airflow entering from the outside. Through this structural design, the external airflow is forced to change its flow direction before entering the heating chamber 21, forming a stable airflow state with rotational characteristics, namely a vortex. This vortex structure significantly enhances the disturbance ability of the airflow inside the heating chamber 21, so that the airflow has stronger lateral diffusion and mixing efficiency when moving in the heating chamber 21. After being heated and volatilized, the object to be detected can be integrated into the vortex more quickly and evenly, thereby improving the distribution consistency of the sample molecules in the entire airflow, thereby improving the accuracy of the detection results of the detection component 3.

[0054] In some embodiments, the inner wall surface of the air guide 51 includes a conical surface 514 and an annular surface 515. The inner diameter of the conical surface 514 gradually increases in the direction from the ventilation pipe 4 to the heating head assembly 2. The annular surface 515 is connected to the end of the conical surface 514 facing away from the ventilation pipe 4. The blade 52 is used to guide the airflow at the vent 511 to the conical surface 514.

[0055] An annular surface 515 is located to the left of the conical surface 514 and is connected to the left end of the conical surface 514. The inner diameter of the conical surface 514 gradually increases from right to left. The multiple blades 52 are used to evenly direct the external airflow entering through the vent 511 onto the surface of the conical surface 514, causing the external airflow to diffuse along the inclined structure of the conical surface 514 and gradually transform into a rotating flow state. The annular surface 515 further guides the swirling flow into the heating chamber 21.

[0056] The passive explosive detector 100 of the embodiment of the present invention realizes effective guidance of the external airflow path by providing a conical surface 514 and an annular surface 515 on the air guide 51. The inner diameter of the conical surface 514 gradually increases along the direction from the ventilation pipe 4 to the heating head assembly 2, so that the incoming swirl airflow can gradually diffuse during the flow process, reducing the airflow disturbance caused by the sudden change of the cross section; the annular surface 515 is located on one side of the conical surface 514, playing the role of transition and stabilizing the airflow, so that the swirl enters the interior of the heating chamber 21 more smoothly. In some embodiments, such as Figure 6 As shown, an annular groove 513 is provided on the air guide 51 corresponding to the vent 511 , the blade 52 is installed in the annular groove 513 , an annular baffle 53 is provided on the side of the blade 52 facing away from the ventilation pipe 4 , and the air outlet duct 42 passes through the vent 511 and the annular baffle 53 .

[0057] An annular groove 513 is provided on the outer periphery of the vent 511. The right ends of the blades 52 are fixedly mounted in the annular groove 513, and the left sides of the blades 52 are fixedly connected to the annular baffle 53. In this embodiment of the present invention, by providing the annular groove 513 on the air guide 51 and fixing the blades 52 therein, and simultaneously providing the annular baffle 53 on the side of the blades 52 facing away from the ventilation pipe 4, the blades 52 are securely mounted. This structural design not only strengthens the connection strength between the blades 52 and the air guide 51, but also effectively prevents undesirable phenomena such as displacement, loosening, or even falling off of the blades 52 under the impact of high-speed airflow, thereby ensuring the stability and reliability of the overall operation of the swirl component 5.

[0058] The outlet duct 42 is arranged between the vent 511 and the annular baffle 53, making the inlet duct 41 and the outlet duct 42 spatially independent and non-interfering, further optimizing the internal air path structure of the device. This design not only improves the overall compactness of the structure, but also helps reduce the size of the device, improves space utilization, and facilitates subsequent assembly and maintenance.

[0059] Optionally, the plurality of blades 52 and the annular baffle 53 are integrally formed.

[0060] In some embodiments, the outlet of the detection component 3 is connected to the inlet of the exhaust fan 7 through a connecting pipe 8, and the connecting pipe 8 is a flexible pipe.

[0061] The connecting tube 8 is a flexible tube to prevent the vibration generated by the exhaust fan 7 from being directly transmitted to the detection component 3, thereby preventing such vibration from interfering with the precise measurement of the detection component 3 and affecting the accuracy of the detection result.

[0062] Furthermore, the flexible tube's bendability allows for flexible adjustment of the relative position between the detection assembly 3 and the exhaust fan 7 according to actual installation requirements, facilitating layout optimization and maintenance of the passive explosive detector 100. Whether adapting to tight space constraints or facilitating maintenance and component replacement, the flexible tube provides significant convenience, making the passive explosive detector 100 not only more stable but also easier to install and debug. Furthermore, the flexible tube can compensate for assembly errors between the detection assembly 3 and the exhaust fan 7, thereby simplifying the assembly process of the passive explosive detector 100.

[0063] Optionally, the connecting tube 8 is a silicone tube or a polyurethane hose.

[0064] In some embodiments, the inner diameter of at least a portion of the connecting pipe 8 gradually increases along the direction from the detection component 3 to the exhaust fan 7 .

[0065] The entire connecting pipe 8 is a tapered pipe, that is, the inner diameter of the connecting pipe 8 gradually decreases from top to bottom, or the upper end of the connecting pipe 8 is a tapered pipe, the inner diameter of the tapered pipe gradually decreases from top to bottom, and the lower end of the connecting pipe 8 is an annular pipe.

[0066] In the passive explosives detector 100 of the present embodiment, the connecting tube 8 features a tapered design, meaning its inner diameter gradually decreases from the detection assembly 3 to the exhaust fan 7, or at least exhibits this tapering characteristic in a certain section. This design ensures a smooth transition of airflow during outward flow, avoiding the sudden cross-sectional changes that can occur in traditional straight tube designs. Airflow flows smoothly within the gradually changing pipe diameter, minimizing turbulence and reducing drag losses. This not only improves the overall airflow transmission efficiency but also ensures the stability and consistency of airflow during delivery.

[0067] Furthermore, the tapered tube design helps reduce vibrations caused by the outflow of air. This improved airflow stability and uniformity reduces mechanical vibrations caused by turbulent airflow, thereby preventing these vibrations from affecting the detection assembly 3. Especially for highly sensitive ion mobility spectrometry, any slight vibration can cause signal drift or misinterpretation. Therefore, reducing unnecessary vibration is crucial for improving the accuracy and repeatability of test results.

[0068] In some embodiments, as Figure 3 As shown, the passive explosive detector 100 includes multiple support members 9 and shock absorbers, and the multiple support members 9 are clamped with the ventilation pipe 4. The shock absorbers are arranged one-to-one with the multiple support members 9, and the shock absorbers are arranged between the support members 9 and the ventilation pipe 4.

[0069] A plurality of support members 9 are sequentially spaced apart along the left-right direction. The support members 9 are provided below the ventilation pipe 4 , and the shock-absorbing member is provided between the support members 9 and the ventilation pipe 4 .

[0070] By arranging a shock-absorbing member between the support member 9 and the ventilation pipe 4, the mechanical vibrations from the external environment or generated during the operation of the equipment can be effectively isolated, preventing these vibrations from being directly transmitted to the inside of the ventilation pipe 4, so that the airflow in the ventilation pipe 4 can flow in a more stable and stable environment, avoiding airflow disturbances or pressure fluctuations caused by vibrations, thereby ensuring the continuity and uniformity of the gas transmission process, and further ensuring the accuracy of the detection results.

[0071] For example, the number of the supporting members 9 and the shock absorbing members is 3 to 6. Optionally, the shock absorbing member is a flexible pad, for example, a silicone pad or a rubber pad.

[0072] In some embodiments, multiple support members 9 are arranged at intervals, a groove is provided on the outer peripheral surface of the ventilation pipe 4 and one of the surfaces of the support member 9, and a protrusion is provided on the outer peripheral surface of the ventilation pipe 4 and one of the surfaces of the support member 9, and the protrusion extends into the groove.

[0073] One of the outer peripheral surface of the ventilation pipe 4 and the surface of the support member 9 is provided with a groove, while the other is provided with corresponding protrusions. These protrusions extend into the corresponding grooves, and the shock absorber is arranged in the groove.

[0074] The passive explosive detector 100 of an embodiment of the present invention utilizes protrusions and grooves to achieve a stable connection between the ventilation pipe 4 and the support member 9, and further arranges a shock absorber inside the groove so that the shock absorber can be tightly embedded in the groove and form effective contact with the ventilation pipe 4 or the support member 9, thereby reducing the impact of external vibrations on the ventilation pipe 4.

[0075] In other embodiments, Figure 9 As shown, the passive explosive detector 100 includes an air return member 13 , which is disposed in the heating chamber 21 . A plurality of first air inlet holes 130 are disposed on the outer periphery of the air return member 13 , and the first air inlet holes 130 are used to connect the air inlet duct 41 and the heating chamber 21 .

[0076] The air return member 13 is formed with an air return port 131 and an air return cavity 132 , and the heating cavity 21 , the air return port 131 , the air return cavity 132 and the air outlet duct 42 are fluidically connected in sequence.

[0077] The return air member 13 is located on the left side of the flow guide 10. The first air inlet 130 on its outer edge is connected to the air guide cavity 512. Once a swirl is generated in the air guide cavity 512, it enters the heating cavity 21 through the first air inlet 130, forming a stable swirling flow within the heating cavity 21. This allows the incoming external airflow to fully mix with the heated and volatilized molecules to be detected, improving the uniformity of their distribution within the airflow. The mixed air then passes through the return air port 131 and the return air cavity 132, and is delivered to the detection assembly 3 via the outlet duct 42 for component analysis.

[0078] Optionally, a plurality of first air inlet holes 130 are arranged at intervals in the circumferential direction around the air return member 13 .

[0079] Optionally, the cross-section of the first air inlet hole 130 is long and arc-shaped, so that the swirl flow can maintain its rotation characteristics without being destroyed when passing through the first air inlet hole 130 .

[0080] In other embodiments, the air return member 13 forms an air guide side wall, and the air guide side wall gradually tilts toward the central axis of the air return member 13 in the direction from the first air inlet 130 toward the return air outlet 131 .

[0081] In other words, the air guide side wall is tapered, that is, the inner diameter of the air guide side wall gradually increases from left to right.

[0082] Since the swirl flow needs to turn back in the heating chamber 21 before it can enter the return air outlet 131, the air flow velocity at the return air outlet 131 is relatively high, and the inner diameter of the air guide side wall gradually increases from left to right, so that after the high-temperature air flow enters the return air chamber 132, the conical air guide side wall causes the air flow to diffuse to disperse the energy of the high-speed air flow, guiding the air flow to be more evenly distributed in the entire return air chamber 132.

[0083] In some embodiments, the passive explosive detector includes a flow guide 10, which is arranged in the air guide cavity 512. The flow guide 10 is formed with a flow guide port 11 and a flow guide cavity 12. The flow guide port 11 is connected to the entrance of the air outlet duct 42, and the flow guide cavity 12 is connected to the heating cavity 21.

[0084] The return air member 13, the flow guide member 10, and the air guide member 51 are arranged sequentially from left to right, and the heating chamber 21, the flow guide chamber 12, the flow guide port 11, and the inlet of the air outlet duct 42 are fluidically connected in sequence. The high-temperature airflow carrying the molecules of the object to be detected flows from the heating chamber 21 through the return air port 131 into the return air chamber 132, then into the flow guide chamber 12, and then through the flow guide port 11 into the air outlet duct 42, and finally flows to the detection component 3.

[0085] The outer periphery of the air guide 10 is provided with a second air inlet 14, which corresponds to and is connected to the first air inlet 130. The air in the air guide cavity 512 passes through the second air inlet 14 and the first air inlet 130 in sequence before entering the heating cavity 21.

[0086] In other embodiments, the inner diameter of the diversion cavity 12 gradually decreases from left to right.

[0087] Therefore, when the high-temperature airflow enters the return air chamber 132, it will first encounter a gradually expanding space, which allows the airflow to gradually diffuse in this area. Through this diffusion process, the airflow is able to consume the kinetic energy generated by the return in the heating chamber 21, reduce turbulence and local pressure fluctuations, and thus achieve a smoother transition. Subsequently, as the airflow continues to move forward, the inner diameter of the guide cavity 12 begins to gradually decrease, guiding the airflow to gradually converge. This tapered design helps to re-centralize the airflow that has diffused and stabilized, forming a more orderly and compact flow state, which facilitates its smooth flow to the outlet duct 42 and ultimately enters the detection component 3 for analysis.

[0088] In other embodiments, Figure 9 As shown, a return air switch 133 is provided at the return air port 131 . The return air switch 133 is electrically connected to the controller of the passive explosive detector 100 . When a preset condition is met, the controller controls the return air switch 133 to open.

[0089] For example, the controller controls the return air switch 133 according to time. At the initial startup of the passive explosive detector 100, the return air switch 133 remains closed, allowing the sample in the heating chamber 21 enough time to be fully heated, thereby avoiding interference with the sample heating process caused by premature introduction of airflow.

[0090] When the preset time threshold is reached, the controller automatically turns on the return air switch 133 and simultaneously starts the blower 6 and exhaust fan 7. At this time, fresh air from the outside is forcefully pushed into the heating chamber 21 by the blower 6, fully mixed with the volatilized molecules of the object to be detected, and then enters the detection component 3.

[0091] The passive explosive detector 100 of the embodiment of the present invention effectively improves the detection accuracy through two aspects of design. On the one hand, by providing the swirl component 5, the airflow entering the heating chamber 21 forms a stable rotating flow state under the action of the blades 52 and the air guide 51, thereby significantly enhancing the disturbance effect of the airflow in the heating chamber 21, so that the molecules of the object to be detected after volatilization by heat can be more evenly distributed in the airflow, thereby increasing the number and distribution uniformity of the molecules of the object to be detected delivered to the detection component 3 per unit time, and improving the detection sensitivity and the accuracy of the results.

[0092] On the other hand, in terms of shock absorption and noise reduction, firstly, since the swirl can smooth the airflow path, it reduces the occurrence of turbulence, making the airflow more orderly and stable, which also helps to reduce unnecessary vibration. Secondly, the passive explosive detector 100 of the embodiment of the present invention provides a plurality of support members 9 to support the ventilation pipe 4 in an interval manner, and configures a shock absorber between the support member 9 and the ventilation pipe 4 to effectively isolate and absorb vibrations from the outside or generated during the operation of the equipment. At the same time, the connecting pipe 8 is made of a flexible material, such as a silicone tube or a polyurethane hose, which further blocks the transmission path of vibration from the exhaust fan 7 to the detection component 3, avoids airflow disturbances or signal fluctuations caused by vibration, and ensures that the detection component 3 operates in a stable environment. Thus, while improving the gas flowability, it also greatly improves the operational stability of the entire system and the repeatability and reliability of the detection results, achieving an all-round performance improvement from airflow optimization to structural shock absorption.

[0093] The passive explosives detector 100 of the present invention is a portable trace explosives detection device based on a combination of thermal desorption and ion mobility spectrometry. It features a compact structure, fast response, high sensitivity, and ease of operation. The following details its complete operating process and the resulting technical benefits.

[0094] The entire detector 100 is mainly composed of a body 1, a heating head assembly 2, a detection assembly 3, a ventilation pipe 4, a swirl component 5, a blower 6, an exhaust fan 7, a connecting pipe 8, a support member 9 and a shock absorber. Among them, the heating head assembly 2 is arranged at one end of the body 1, and a heating chamber 21 is provided inside for accommodating the sample and heating and burning it; the ventilation pipe 4 runs through the inside of the body 1 to form an air inlet duct 41 and an air outlet duct 42, which are respectively responsible for the introduction of external air and the discharge of gas after detection; the detection assembly 3 is located at the other end of the body 1, and is used to identify and analyze the target molecules carried in the air flow; the swirl component 5 is arranged in the air inlet duct 41 or the connection area between it and the heating chamber 21, and is used to optimize the airflow shape; the blower 6 and the exhaust fan 7 are respectively arranged at the ends of the air inlet duct 41 and the air outlet duct 42, and cooperate to drive the airflow circulation; the connecting pipe 8 uses a flexible material (such as silicone or polyurethane hose) to connect the detection assembly 3 and the exhaust fan 7 to reduce shock and noise; multiple support members 9 are arranged at intervals below the ventilation pipe 4, and shock absorption members are used to achieve shock absorption protection for the entire system.

[0095] When the device is started, the sample to be tested is first placed in the heating chamber 21 by opening the heating head assembly 2. Subsequently, the controller controls the return air switch 133 to remain in a closed state to ensure that the sample is not disturbed by the airflow in the initial stage and is fully heated and volatilized. After a preset time, the controller automatically turns on the return air switch 133 and starts the blower 6 and the exhaust fan 7 at the same time. At this time, the external air enters the air inlet duct 41 under the action of the blower 6, and forms a stable rotating airflow under the guidance of the blades 52 in the swirl component 5. After being further stabilized by the conical surface 514 and the annular surface 515 of the air guide 51, the swirl airflow enters the heating chamber 21, is fully mixed with the molecules of the object to be tested that are heated and volatilized, and forms a high-temperature carrying airflow.

[0096] The mixed airflow passes sequentially through the return air port 131, the return air chamber 132, and the guide chamber 12, ultimately being delivered to the detection assembly 3 via the air outlet duct 42. The detection assembly 3 uses ion mobility spectrometry to ionize, separate, and detect molecules in the gas under test. Different types of explosive molecules exhibit different migration times due to their unique ion mobility, enabling qualitative and quantitative analysis. To improve detection accuracy, the connecting tube 8 utilizes a flexible tapered design, which not only enhances airflow transmission efficiency but also effectively reduces turbulence caused by vibration and sudden changes in cross-section, thereby preventing any impact on detection signal stability.

[0097] Furthermore, in terms of mechanical structure, multiple supports 9 are evenly distributed along the left and right sides below the ventilation duct 4. A shock absorber (such as a silicone or rubber pad) is placed between each support 9 and the ventilation duct 4, forming a multi-point vibration reduction system. This design effectively isolates external environmental vibrations from the mechanical vibrations generated during equipment operation, preventing vibrations from being transmitted into the ventilation duct 4, ensuring smooth airflow and further improving the accuracy and repeatability of test results.

[0098] In summary, the passive explosive detector 100 of the embodiment of the present invention achieves efficient regulation of the airflow path through the synergistic effect of the swirl component 5, the blower 6 and the exhaust fan 7, significantly enhances the mixing efficiency between the sample molecules and the airflow, and improves the detection sensitivity and response speed. At the same time, through structural optimization means such as flexible connections and shock-absorbing supports, the vibration interference during the operation of the instrument is effectively reduced, providing a more stable working environment for the detection component 3. Overall, the detector has the advantages of high detection accuracy, stable operation, and strong anti-interference ability. It is suitable for a variety of explosive rapid detection scenarios such as airport security, border inspection, and security in key locations, and has broad prospects for promotion and application.

[0099] Finally, it should be noted that the above embodiments are only used to illustrate the technical solutions of the present invention, rather than to limit it. Although the present invention has been described in detail with reference to the aforementioned embodiments, those skilled in the art should understand that they can still modify the technical solutions described in the aforementioned embodiments, or make equivalent replacements for some of the technical features therein. However, these modifications or replacements do not deviate the essence of the corresponding technical solutions from the spirit and scope of the technical solutions of the various embodiments of the present invention.

Claims

1. A passive explosive detector, characterized in that: include: Body (1); A heating head assembly (2) is arranged at one end of the body (1), and a heating cavity (21) is formed in the heating head assembly (2); A detection component (3) is arranged in the body (1); A ventilation pipe (4) having an air inlet duct (41) and an air outlet duct (42) formed therein, wherein the air inlet duct (41) is connected to the heating chamber (21) and the outside, and the air outlet duct (42) is connected to the heating chamber (21) and the detection component (3); The swirl component (5) is located in the air inlet duct (41), or between the air inlet duct (41) and the heating chamber (21).

2. The passive explosive detector according to claim 1, characterized in that: The air inlet duct (41) surrounds the outer periphery of the air outlet duct (42); an air blower (6) is provided at one end of the air inlet duct (41) away from the heating chamber (21); and an exhaust fan (7) is provided at one end of the detection component (3) away from the air outlet duct (42).

3. The passive explosive detector according to claim 2, characterized in that: The swirl component (5) comprises: An air guide member (51), the air guide member (51) being formed with a vent (511) and an air guide cavity (512), the vent (511) being connected to the air inlet duct (41), and the air guide cavity (512) being connected to the heating cavity (21); A plurality of blades (52) are distributed at intervals on the periphery of the vent (511) and are used to guide the airflow at the vent (511) to the periphery of the vent (511) and into the air guide cavity (512).

4. The passive explosive detector according to claim 3, characterized in that: The inner wall surface of the air guide member (51) comprises: a conical surface (514), wherein the inner diameter of the conical surface (514) gradually increases in a direction from the ventilation pipe (4) to the heating head assembly (2); an annular surface (515), the annular surface (515) being connected to an end of the conical surface (514) facing away from the ventilation pipe (4); The blades (52) are used to guide the airflow at the vent (511) toward the conical surface (514).

5. The passive explosive detector according to claim 3, characterized in that: An annular groove (513) is provided on the air guide member (51) corresponding to the vent (511), the blade (52) is mounted in the annular groove (513), an annular baffle (53) is provided on the side of the blade (52) facing away from the ventilation pipe (4), and the air outlet duct (42) is provided through the vent (511) and the annular baffle (53).

6. The passive explosive detector according to claim 2, characterized in that: The outlet of the detection component (3) is connected to the inlet of the exhaust fan (7) via a connecting pipe (8), and the connecting pipe (8) is a flexible pipe.

7. The passive explosive detector according to claim 6, characterized in that: The inner diameter of at least part of the connecting pipe (8) gradually increases in a direction from the detection component (3) to the exhaust fan (7).

8. The passive explosive detector according to any one of claims 1 to 7, characterized in that: The passive explosive detector comprises: A plurality of support members (9) are clamped to the ventilation pipe (4); The shock absorbing member is provided in a one-to-one correspondence with the plurality of support members (9), and the shock absorbing member is provided between the support member (9) and the ventilation pipe (4).

9. The passive explosive detector according to claim 8, characterized in that: A plurality of the support members (9) are arranged at intervals, a groove is provided on the outer peripheral surface of the ventilation pipe (4) and one of the surfaces of the support members (9), and a protrusion is provided on the outer peripheral surface of the ventilation pipe (4) and one of the surfaces of the support members (9), and the protrusion extends into the groove.

10. The passive explosive detector according to claim 3, characterized in that: The passive explosive detector comprises: A flow guide member (10), the flow guide member (10) being arranged in the air guide cavity (512), the flow guide member (10) being formed with a flow guide port (11) and a flow guide cavity (12), the flow guide port (11) being connected to the inlet of the air outlet duct (42), and the flow guide cavity (12) being connected to the heating cavity (21).

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