Cold cathode X-ray vehicle detection emission box and optical arrangement method

Abstract

The invention belongs to the technical field of radiation imaging detection, and particularly discloses a cold cathode X-ray vehicle detection emission box and an optical arrangement method thereof. The emission box comprises an emission box shell, an emission unit and an X-ray source. According to the X-ray source, the cold cathode X-ray tube and the high-voltage part of the high-voltage power supply module are integrally immersed in the high-voltage insulating oil, natural heat dissipation is achieved through the emission box shell, and the structure is compact and reliable. And a replaceable optical filter assembly and a lead shielding lining are arranged in the transmitting unit, so that the safety and the flexibility are ensured. By designing the sizes and positions of the light guide strip and the light outlet aperture, the light guide strip and the light outlet aperture are accurately matched with the geometric parameters and the preset coverage range of the target lane. The invention further provides an optical arrangement method, according to parameters such as lane width and detector height, the installation position and size of each component are accurately determined through geometric calculation, accurate projection of X-ray beams is achieved, scattering is effectively reduced, and the imaging quality is remarkably improved while radiation safety is guaranteed.

Description

TECHNICAL FIELD

[0001] The present application relates to the technical field of radiation imaging detection, in particular to a cold cathode X-ray vehicle detection emission box and an optical arrangement method thereof, which is suitable for a vehicle rapid security check system in places such as highways, customs and logistics. BACKGROUND

[0002] X-ray imaging technology is widely used in the field of vehicle detection, and security inspection, contraband investigation and other purposes are achieved by perspective scanning of vehicles. At present, the technical scheme of the emission source for vehicle X-ray detection mainly includes two types.

[0003] The first type is an integrated closed scheme. The X-ray tube, high-voltage generator and oil circulation cooling system are all integrated and packaged in a metal shielding box to form a closed whole. Its advantages are good shielding effect, safety and reliability, strong environmental adaptability, and convenience for users to integrate the system (usually only low-voltage power supply and signal interface need to be provided). However, this scheme also has obvious disadvantages: the integrated device is large in size and weight, and lacks flexibility; the X-ray beam angle is usually fixed and cannot be adjusted, resulting in a large irradiation area range, which cannot accurately adapt to the detection needs of different lane widths and vehicle profiles, and may cause waste of radiation dose or mismatch of imaging area.

[0004] The second type is a split scheme. The heavy high-voltage generator is separated from the X-ray tube head with a cooling system, and the two are connected through a high-voltage cable. Its advantage is that the heavy generator can be placed remotely, making the X-ray tube head part very light and compact, which is convenient for installation on a mechanical arm, a narrow space or a mobile platform. However, its disadvantages are also prominent: the system needs to handle complex high-voltage connection and insulation problems, and the overall reliability is challenged; the beam angle is fixed and the irradiation range is large, making it difficult to achieve precise control of radiation dose and optimization of imaging area.

[0005] In summary, the existing technical schemes often sacrifice the flexibility of irradiation angle and the precision of radiation dose in the pursuit of miniaturization, lightness or ease of integration, making it difficult to adapt the optical arrangement to specific lane geometric parameters and vehicle characteristics, thereby affecting the further improvement of imaging quality and detection efficiency. Therefore, there is an urgent need for an X-ray emission device for vehicle detection and a design method that can balance compact structure, safety and reliability, and achieve precise adjustment of beam angle and irradiation range. SUMMARY

[0006] The present application aims to provide a cold cathode X-ray vehicle detection emission box and an optical arrangement method thereof, to realize efficient, stable and safe X-ray detection of vehicles and adapt to the geometric parameters and detection needs of different lanes.

[0007] To achieve the above object, the present application provides the following technical solutions.

[0008] In a first aspect, the present application provides a cold cathode X-ray vehicle detection emission box, comprising an emission box shell, an emission unit arranged in the emission box shell, and an X-ray source for providing X-rays for the emission unit. The X-ray source comprises a cold cathode X-ray tube and a high-voltage power supply module, the cold cathode X-ray tube and the high-voltage part of the high-voltage power supply module are integrally immersed in high-voltage insulating oil, and heat exchange with the outside is performed through the shell of the X-ray source. The emission unit comprises an emission unit shell and a filter assembly arranged in the emission unit shell and located in the beam direction of the X-ray source. The emission box shell is provided with a light guide strip, the emission unit shell is provided with a light outlet hole, and the size and relative position of the light guide strip and the light outlet hole are matched with the geometric parameters of the target lane and the preset X-ray coverage range.

[0009] In addition to the above technical features, the present application is also optimized and improved in the following aspects:

[0010] As a preferred technical solution of the present application, the high-voltage power supply module adopts a distributed power supply module, the high-voltage components of which are immersed in the high-voltage insulating oil and electrically connected to the low-voltage control module located outside the oil through wires.

[0011] As a preferred technical solution of the present application, an open airbag in communication with the oil cavity containing the high-voltage insulating oil is further included, which is used to discharge gas to maintain the internal pressure of the oil cavity when the high-voltage insulating oil is heated and expanded.

[0012] As a preferred technical solution of the present application, the cold cathode X-ray tube is suspended and fixed in the interior of the X-ray source.

[0013] As a preferred technical solution of the present application, the filter assembly comprises a fixed filter and a movable filter; the fixed filter is a groove structure formed on the emission unit shell by machining; and the movable filter is a metal sheet that can be placed in the groove.

[0014] As a preferred technical solution of the present application, the material of the movable filter is aluminum or copper, and the shape is a square with a side length matching the groove.

[0015] As a preferred technical solution of the present application, a lead shielding lining is arranged on the inner side of the emission unit shell.

[0016] As a preferred technical solution of the present application, a constant temperature and humidity system arranged in the interior of the emission box shell is further included, which is used to maintain the ambient temperature in the box.

[0017] In a second aspect, the present application provides an optical arrangement method for the cold cathode X-ray vehicle detection emission box, comprising the following steps:

[0018] S1: According to the lane width (L), the detector installation height (Y0) and the target vehicle tire height (h), the angle θ between the X-ray underline of the emission box and the horizontal direction is calculated, and the vehicle runs in front of the roadside on the side of the emission box, then θ is maximum, wherein θ = arctan((h-Y0) / L);

[0019] S2: The installation position point of the cold cathode X-ray tube is determined, so that the beam center line of the point forms an angle β with the X-ray underline, and β is not greater than the maximum beam angle of the X-ray tube;

[0020] S3: Based on the geometric relationship determined in steps S1 and S2, the installation position (u) of the emission box and the total length (Z) of the light guide strip are calculated;

[0021] S4: Based on the results of step S3, the installation position of the emission unit in the box and the length (D) of the light hole gap are calculated;

[0022] S5: Based on the results of step S4, the installation position of the X-ray source in the emission unit and the corresponding square side length (n) of the light outlet are calculated.

[0023] The present application provides a further optimization scheme of the optical arrangement method, wherein based on the preset X-ray scattering angle (α), the width (i) of the light hole gap and the width (j) of the light guide strip are calculated respectively,

[0024] Wherein, i = 2 × e × tan α, j = 2 × a × tan α,

[0025] e is the distance from the tube position to the inner edge of the hole gap, a is the distance from the tube position to the inner edge of the light guide strip, and α is 2°-5°.

[0026] The cold cathode X-ray vehicle detection emission box and the optical arrangement method thereof provided by the present application can produce the following significant beneficial effects compared with the prior art:

[0027] 1. Structure simplification and reliability improvement: By immersing the cold cathode X-ray tube and the high-voltage part of the high-voltage power supply in high-voltage insulating oil as a whole, and utilizing the heat exchange between the X-ray source shell and the external environment to achieve natural air cooling heat dissipation. This design replaces the complex and bulky forced oil circulation or water circulation cooling system in the traditional scheme, not only greatly reduces the overall volume and weight of the emission box, but also simplifies the structure, improves the reliability and environmental adaptability of the system.

[0028] 2. Modularization and flexibility: The high-voltage power supply adopts a distributed module design (high-voltage oil immersion, low-voltage externalization), and uses ordinary wires for connection, reducing the insulation requirements and complexity of the high-voltage connection part. The filter assembly adopts a combination design of "fixed groove + replaceable metal sheet" (such as aluminum sheet or copper sheet), allowing users to quickly and conveniently replace the filter according to specific detection requirements (such as energy spectrum, dose), enhancing the flexibility and scene adaptability of the system.

[0029] 3. Enhanced safety: By connecting the open airbag with the oil chamber, the internal pressure changes caused by the thermal expansion and contraction of the high-voltage insulating oil can be adaptively adjusted, effectively protecting the internal electronic components and the performance stability of the insulating oil, prolonging the service life of the equipment. The inside of the emission unit is additionally provided with a lead or aluminum shielding lining, which, in combination with a precise mechanical structure design, can maximize the shielding of X-rays to prevent radiation leakage, ensuring the safety of operating personnel and the environment.

[0030] 4. Optimization of irradiation accuracy and imaging quality: A set of optical arrangement and calculation methods based on lane geometric parameters (width, detector height, vehicle feature height) is innovatively proposed. By accurately calculating key parameters such as the installation position of the emission box, the beam angle (such as the along-line angle θ), the light guide strip size (length Z, width j), and the internal light emission hole gap of the emission unit (length D, width i), the X-ray beam can be precisely controlled in the target detection area (such as vehicle tires, chassis). This effectively avoids the problem of excessive X-ray irradiation range and severe scattering in traditional solutions, achieving precise radiation dose control while significantly improving the contrast and clarity of the imaging.

[0031] 5. Prolonged equipment life: The cold cathode X-ray tube is installed in a suspended manner, reducing the mechanical stress on its anode target, which helps to reduce wear and tear, thereby prolonging the service life of the X-ray tube. Combined with the stable control of the constant temperature and humidity system on the box environment, better working conditions are provided for the internal precision electronic components and X-ray source, further ensuring the stability of the system in long-term operation.

[0032] In summary, the present application successfully realizes a cold cathode X-ray vehicle detection emission box with compact size, light weight, efficient heat dissipation, radiation safety, precise irradiation, and easy maintenance through integrated innovative structural design, modularized functional components, and precise optical arrangement methods. This solution is particularly suitable for vehicle security scenarios that have high requirements for installation space, system flexibility, and imaging quality. BRIEF DESCRIPTION OF DRAWINGS

[0033] Fig. 1 Figure 1 is a schematic diagram of the overall structure of the cold cathode X-ray vehicle detection emission box of the present application;

[0034] Fig. 2Structure diagram of the emission unit of the emission box of the cold cathode X-ray vehicle detection device of the present application;

[0035] Fig. 3 Structure diagram of the optical arrangement of the emission box of the cold cathode X-ray vehicle detection device of the present application;

[0036] Fig. 4 Structure diagram of the use state of the emission box of the cold cathode X-ray vehicle detection device of the present application.

[0037] Reference signs:

[0038] (I) Emission box shell part:

[0039] 1-emission box shell,

[0040] 11-light guide strip,

[0041] Emission unit part:

[0042] 2-emission unit,

[0043] 21-emission unit shell,

[0044] 211-light outlet hole gap,

[0045] 212-lead shielding lining,

[0046] 22-filter assembly,

[0047] 221-fixed filter,

[0048] 222-movable filter,

[0049] (II) X-ray source part:

[0050] 3-X-ray source,

[0051] 31-cold cathode X-ray tube,

[0052] (III) Other components:

[0053] 4-open air bag,

[0054] 5-constant temperature and humidity system. DETAILED DESCRIPTION

[0055] The preferred embodiments of the present application are described below in conjunction with the accompanying drawings, and it should be understood that the preferred embodiments described herein are only used to illustrate and explain the present application, and are not used to limit the present application.

[0056] I. Description of the descriptive language in the present application

[0057] The embodiments given in combination with the technical solutions of the present application are to make the present application more thorough and complete, and fully express the scope of the present application to those skilled in the art. It should be noted that: unless otherwise specified in the present application, the relative arrangement of the components set forth in these embodiments should be interpreted as merely exemplary, and not as a limitation on the technical solutions of the present application.

[0058] In the present application, if the terms such as "up", "down", "left", "right", "bottom", "top" and the like are used, they are defined with respect to the direction in the drawings, and are only used to represent the relative positional relationship. When the absolute position of the described object changes, the relative positional relationship may also change accordingly. These or other orientation terms should not be understood as limiting terms.

[0059] In the present application, the terms "one", "a", "an", "the", and the like similar words do not represent quantity limitation, and can represent singular or plural. The terms "include", "contain", "have", and any variations thereof in the present application are intended to cover non-exclusive inclusion; if the present application involves the terms "first", "second", "third", etc., they are only to distinguish similar objects, and do not represent a specific order of the objects.

[0060] In the present application, when it is described that a specific device is located between a first device and a second device, there can be an intermediate device between the specific device and the first device or the second device, or there can be no intermediate device. When it is described that a specific device is connected to other devices, the specific device can be directly connected to the other devices without an intermediate device, or it can not be directly connected to the other devices with an intermediate device.

[0061] In addition, the technologies and devices known to those of ordinary skill in the related art are not discussed in detail, but in appropriate cases, the technologies and devices should be considered as part of the specification.

[0062] Second, the core technical problem to be solved by the technical solutions of the present application

[0063] The two mainstream technical solutions of the existing vehicle X-ray detection have obvious deficiencies. The integrated closed type solution integrates the ray tube, high voltage generator and the like, has good shielding effect and is convenient for integration, but the whole is heavy and the beam angle is fixed, which is difficult to flexibly match different lanes and vehicle profiles, and is easy to cause radiation waste or imaging area mismatch. The split type solution separates the generator and the tube head, improves the installation flexibility, but still cannot adjust the beam angle, and the high voltage connection is complex and the reliability faces challenges. The common defects of the two are that the irradiation range is fixed and the radiation dose control precision is low, and the optical arrangement cannot be adjusted adaptively according to the specific scene, which restricts the optimization of imaging quality and detection efficiency. Therefore, the current technology cannot meet the needs of compact structure, safety and reliability, and precise and adjustable irradiation.

[0064] III. Based on the above problems, the present application provides a technical solution to solve the above problems. The technical solution of the present application is described in detail below in combination with the accompanying drawings and specific embodiments. It should be understood that the specific embodiments described herein are only used to explain the present application and do not limit the protection scope of the present application. Figs. 1-4 The technical solution of the present application is described in detail below in combination with the accompanying drawings and specific embodiments. It should be understood that the specific embodiments described herein are only used to explain the present application and do not limit the protection scope of the present application.

[0065] Embodiment 1

[0066] As shown in the drawings, the present embodiment provides a cold cathode X-ray vehicle detection emission box for vehicle security check, which can realize accurate, safe and efficient X-ray scanning of vehicle area. Figs. 1 to 3 (I) Structure and detailed description

[0067] The cold cathode X-ray vehicle detection emission box of the present embodiment mainly includes an emission box shell 1, an emission unit 2, an X-ray source 3, and auxiliary open airbags 4 and constant temperature and humidity systems 5.

[0068] The emission box shell 1 is made of stainless steel and has sufficient mechanical strength and corrosion resistance. Its inside is lined with aluminum plate, which mainly functions to exchange heat with external air and assist in shielding scattered X-rays. The emission box shell 1 as a whole has an IP65 or above protection level, which can prevent dust and water.

[0069] On the side wall of the emission box shell 1 facing the lane, a long strip-shaped opening is provided, and a light guide strip 11 is installed.

[0070] The light guide strip 11 is made of engineering plastic (such as polycarbonate) with low X-ray absorption, which has the functions of sealing, dustproof, waterproof and guiding X-ray beam. Its length Z and width j (thickness direction) are accurately calculated according to the target lane parameters (calculation method see the "optical arrangement method" section below). This design, together with the subsequent optical arrangement method, converts external geometric requirements into internal precise mechanical constraints, which is the key interface to realize accurate irradiation.

[0071] The emission unit 2 is a separate shielding module installed inside the emission box shell 1.

[0072] The emission unit shell 21 is made of aluminum or steel structure, and the inner side of the key area (especially the non-beam direction) is provided with a lead shielding lining 212, which is used to prevent X-rays from leaking in unintended directions to the maximum extent and to ensure radiation safety.

[0073] The emission unit shell 21 is made of aluminum or steel structure, and the inner side of the key area (especially the non-beam direction) is provided with a lead shielding lining 212, which is used to prevent X-rays from leaking in unintended directions to the maximum extent and to ensure radiation safety.

[0074] At the position corresponding to the light guide strip 11 of the emission unit shell 21, an out-light hole 211 is opened. The length D and width i of the out-light hole 211 are also precisely calculated to ensure that the X-ray beam can pass without obstruction and to control the scattering range of the beam. The lead shielding lining 212 cooperates with the precisely calculated out-light hole 211 to form a unified body of "safety shielding" and "precise beam emission", which maximizes the utilization efficiency of useful rays under the premise of ensuring radiation safety.

[0075] The filter assembly 22 is arranged in the emission unit shell 21 and located on the beam path of the X-ray source 3. The filter assembly 22 includes:

[0076] The fixed filter 221 is not a separate part, but is arranged on the emission unit shell 21 (which is part of the X-ray source 3) and is a square groove structure with a side length of n and a depth of 3 mm directly milled by CNC machining. This integrated design of the fixed filter and the emission unit shell 21 not only has a stable structure, but also shortens the optical path and reduces unnecessary scattering interfaces.

[0077] The movable filter 222 is a square metal sheet with a side length of n and a thickness slightly less than 3 mm. The material can be selected as aluminum or copper with a purity of more than 95% according to the imaging requirements. When in use, the metal sheet is directly placed in the groove. This design makes the replacement of the filter very convenient without the need to disassemble the complex structure. The modular combination of the movable filter 222 and the fixed filter 221 enables the system to quickly adjust the energy spectrum according to different detection objects, which further cooperates with the precise beam control to realize the full-range imaging optimization from "dose" to "energy spectrum".

[0078] The X-ray source 3 generates X-rays and is installed as a whole in the emission unit 2.

[0079] Specifically, the X-ray source 3 includes a metal shell, and a sealed oil cavity is formed inside.

[0080] The cold cathode X-ray tube 31 and the high-voltage components (such as high-frequency transformers and high-voltage rectifier circuits) of the high-voltage power supply module are immersed as a whole in the high-voltage insulating oil in the oil cavity. The insulating oil also plays the roles of insulation, heat dissipation and moisture prevention.

[0081] The high-voltage power module adopts a distributed design. The core circuit (high-voltage components) for generating high voltage is immersed in oil, while the low-voltage control circuit (such as switch control, signal interface, etc.) is arranged outside the oil cavity. The two are connected by ordinary insulated wires without the need for heavy high-voltage cables. This distributed design of "high-voltage oil immersion and low-voltage externalization" cooperates with the overall oil immersion heat dissipation scheme and is the core of realizing miniaturization and high reliability in this embodiment: it not only solves the problem of high-voltage components by taking advantage of the excellent insulation and heat dissipation performance of oil, but also greatly reduces the complexity and failure points of the system by simplifying the connection.

[0082] Suspension installation: the cold cathode X-ray tube 31 is fixed on its mounting bracket in a suspended manner through a flexible silicone sleeve and fasteners. This installation method effectively buffers the vibration during transportation and use, reducing the mechanical stress on the anode target. The suspension installation cooperates with the subsequent constant temperature and humidity system 5 to protect the fragile X-ray tube from mechanical vibration and environmental constant temperature, respectively, and together ensure the beam stability and service life.

[0083] The shell of the emission unit shell 21 serves as one of the walls of the oil cavity, and is made of aluminum with a purity of more than 95%, which is beneficial to heat dissipation and the grooves on the shell constitute the fixing of the filter 221.

[0084] The open air bag 4 is a flexible rubber or silicone air bag, which is connected to the top of the oil cavity containing high-voltage insulating oil through a pipeline. When the oil temperature rises and the insulating oil expands, the air in the oil cavity is pressed into the air bag; when the oil temperature decreases, the air in the air bag is sucked back into the oil cavity. This design cooperates with the sealed oil cavity to form a self-adaptive pressure buffer system. It can automatically balance the change of oil volume caused by temperature change, maintain the stability of the pressure in the oil cavity, and protect the integrity of the sealing element, prevent the performance degradation of the insulating oil, and ensure the long-term reliable operation of the internal high-voltage circuit under thermal cycling.

[0085] The constant temperature and humidity system 5 is installed in the internal space of the emission box shell 1, but is not connected to the oil cavity. The system includes semiconductor refrigeration pieces, heaters, fans and humidity sensors, which are used to maintain the temperature and humidity of the inside of the emission box (mainly the environment where the low-voltage control circuit is located) in a stable range (for example, 25℃±3℃, relative humidity <60%), to ensure the reliable work of electronic components. As mentioned earlier, the constant temperature and humidity system 5 cooperates with the suspension installation, oil immersion heat dissipation and other technical features to provide a stable internal micro-environment for the entire system, which is an important part of ensuring long-term accuracy and reliability.

[0086] (II) Working principle

[0087] System start: After the control system receives the start detection signal, the constant temperature and humidity system 5 first works to ensure the stability of the environment in the box. Then, the low-voltage control circuit supplies power to the high-voltage power module.

[0088] X-ray generation: The low-voltage part of the high-voltage power module controls the operation of the high-voltage components immersed in oil, generates pulsed high voltage, and applies it to the cold cathode X-ray tube 31 also immersed in oil. The cathode of the cold cathode X-ray tube 31 emits electrons under the action of a high-voltage electric field, bombards the anode target, and generates X-rays. The entire process benefits from the oil immersion heat dissipation and pressure balancing system, heat is efficiently dissipated, internal pressure is stable, and the operating point is maintained.

[0089] Beam shaping and emission: The generated X-rays first pass through the groove (fixed filter 221) on the emission unit shell 21 and the movable filter 222 placed in the groove for energy spectrum filtering. Then, the ray beam passes through the precisely calculated opening (light emission hole 211) on the emission unit shell 21 and then through the light guide strip 11 on the emission box shell 1, finally forming a fan-shaped beam surface matching the lane geometry, accurately irradiating the tire and chassis area of the vehicle in motion. This is the final embodiment of the coordinated action of each component: the oil immersion source provides stable rays, the filter optimizes the energy spectrum, the lead shielding ensures safety, and the precisely determined aperture and light guide strip by the optical arrangement method accurately guide the rays to the target area, achieving the upgrade from "area coverage" to "line precision" in the irradiation range.

[0090] Heat dissipation and protection: The heat generated by the high-voltage components and X-ray tube is transferred to the high-voltage insulating oil. The hot oil transfers heat to the emission unit shell 21 and the emission box shell 1 through convection, and finally dissipates through natural convection (air cooling) between the emission box shell 1 and the outside air. The open airbag 4 balances the oil cavity pressure in real time. The suspended cold cathode X-ray tube 31 avoids stress concentration. The three systems of heat dissipation, pressure equalization, and anti-vibration work together to form a protection system that ensures the long-term, reliable, and stable operation of the equipment in complex outdoor environments.

[0091] (Three) Optical arrangement method of the embodiment

[0092] The installation and internal structure size of the embodiment are strictly determined according to the following method to achieve accurate irradiation. This method is the key bridge connecting external requirements and internal structure, and its coordination with the above hardware features is the soul of the invention to achieve excellent technical effects.

[0093] Assume the target lane width L = 3.5 meters, the detector installation height Y0 = 0.4 meters, and the tire height of the truck to be inspected h = 0.8 meters. The vehicle drives along the road in front of the emission box side, then θmax.

[0094] S1: Calculate the angle θ of the lower edge

[0095] θ = arctan((h-Y0) / L) = arctan((0.8-0.4) / 3.5)≈6.5° This angle defines the lower boundary that the X-ray beam needs to cover, and is the reference for all subsequent calculations.

[0096] S2: Determine the tube exit angle β

[0097] The maximum exit angle of the cold cathode X-ray tube 31 is selected as £ (Eta) = 80°. To ensure full coverage of the required area, the angle β between the center of the X-ray tube and the top of the side of the car (i.e., the upper X-ray line) is £ = 80°. From this, the theoretical installation position of the X-ray tube in space can be determined.

[0098] S3: Calculate the position of the emission box u and the length of the light guide strip Z

[0099] According to the principle of geometric similar triangles, combined with the known θ, β (η = β), and the height of the car h, the horizontal distance w from the X-ray tube to the car can be solved by simultaneous equations.

[0100] Then, according to the installation site conditions, the reserved distance u of the emission box from the car is determined (e.g., u = 0.2 meters).

[0101] Finally, the segment lengths Z1 and Z2 of the light guide strip above and below the horizontal line are calculated, and the total length Z = Z1 + Z2. In this example, Z ≈ 0.25 meters is calculated. The calculation of the length Z of the light guide strip makes the opening on the emission box shell no longer a simple opening, but a first precise constraint in the vertical direction of the light beam.

[0102] S4: Calculate the position of the emission unit and the length of the light-emitting hole D

[0103] The distance b from the inner wall of the emission box shell (light guide strip position) to the outer wall of the emission unit shell is known. Using similar triangles, the segment lengths d1 and d2 of the light-emitting hole can be calculated from Z1, Z2, and a (the distance from the X-ray tube to the light guide strip, which is obtained from the previous step), and the total length D = d1 + d2. In this example, D ≈ 0.20 meters is calculated. This step precisely locks the geometric relationship between the light-emitting hole 211 inside the emission unit and the light guide strip 11 outside, forming a second precise checkpoint for light beam constraints.

[0104] S5: Calculate the position of the X-ray source and the side length n of the light-emitting port

[0105] The distance f from the inner wall of the emission unit housing (the aperture position) to the outer wall of the emission unit housing is known. Similarly, using the geometric relationship, the segment lengths g1 and g2 of the X-ray source light outlet in the vertical direction are calculated from d1, d2, e (the distance from the ray tube to the aperture, obtained in the previous step). Since the light outlet is square, its side length n = g1 + g2. In this example, n ≈ 0.05 meters is calculated. This is also the side length of the fixed filter groove and the movable filter. This step finally unifies the size of the innermost emission unit housing (and the filter assembly thereon) with the geometry of the entire optical link, ensuring that the beam shape from the source is consistent with the final required illumination profile.

[0106] S6: Determine the aperture and light guide strip width i, j

[0107] Considering the scattering of X-rays, set the scattering angle α = 5°.

[0108] Aperture width i: i = 2 × e × tan α. Calculated i ≈ 0.017 meters.

[0109] Light guide strip width j: j = 2 × a × tan α. Calculated j ≈ 0.022 meters.

[0110] The design of widths i and j is based on the understanding of the physical properties of X-rays (scattering angle) and the aforementioned calculations based on geometric optics, which together ensure the efficient passage of useful rays within the allowed scattering range, while strictly limiting invalid scattering to the minimum range. This directly reduces the environmental background radiation and improves the signal-to-noise ratio of imaging.

[0111] (Four) Technical effect description

[0112] Through the systematic integration and deep synergy of the above technical features, the embodiment achieves overall technical effects far beyond the simple addition of individual component functions: synergistically achieving miniaturization, high reliability, and long life: "oil immersion heat dissipation", "distributed high-voltage power supply", "open airbag", and "suspended installation" work together with "constant temperature and humidity system". They replace the large and complex forced cooling system and high-loss components, significantly reducing the volume and weight, and greatly improving the operation reliability and core device life of the system in harsh outdoor environments through multiple protection mechanisms (pressure equalization, anti-vibration, constant temperature).

[0113] Synergistic realization of safety, precision and flexible imaging: "Lead shielding lining" and "replaceable filter" provide basic safety and imaging flexibility. The core is that "optical arrangement method" and the above-mentioned hardware (light guide strip 11, light emitting hole gap 211, filter assembly 22, installation position of X-ray source 3) form a closed-loop collaborative design. This method converts the lane geometric parameters (L, Y0, h) and physical parameters (scattering angle a) into a series of precise mechanical dimensions and installation positions (u, Z, D, n, i, j), so that the whole system is "calibrated" to the specific detection scene from the source. As a result, the X-ray dose is highly concentrated on the target scanning line, the scattered radiation is minimized, and the environmental radiation safety level is improved to a new height while significantly improving the imaging contrast and clarity.

[0114] System-level optimization solves industry pain points: Through the above-mentioned deep cooperation, the invention successfully solves the long-standing contradiction between the traditional integrated solution (heavy, large irradiation range) and the split solution (complex, high-voltage connection risk). Finally, a highly integrated, intelligent adaptive, precise irradiation, safe and reliable vehicle X-ray detection and emission solution is provided.

[0115] Embodiment 2

[0116] The main difference between this embodiment and embodiment 1 is the material of the movable filter 222 and the scattering angle selection in the optical arrangement. The other structural features and connection relationships are the same.

[0117] In this embodiment, the movable filter 222 is made of a copper sheet with a thickness of 0.5 mm. The filtering effect of copper sheet on low-energy X-rays is stronger than that of aluminum sheet, which can produce X-ray beams with higher hardness and stronger penetration, suitable for detecting heavy vehicles or container vehicles.

[0118] Corresponding optical arrangement adjustment: When implementing the sixth and seventh steps of the optical arrangement method, considering that the scattering characteristics of the rays may change slightly after using a copper filter, this embodiment selects a more conservative scattering angle a = 3° for calculation. Therefore, the width of the light emitting hole gap 211 i = 2 × e × tan 3° and the width of the light guide strip 11 j = 2 × a × tan 3°, compared with embodiment 1 (a = 5°), the calculated i and j values are smaller, which means that the transverse size of the light emitting hole gap and the light guide strip is narrower, and the transverse constraint of the X-ray beam is more strict, further reducing the possible scattering to adapt to the precise control requirements of the higher penetration beam.

[0119] Due to the adoption of the copper movable filter, the average energy of the X-ray output by the transmitting box is higher, the penetrating power is stronger, and the chassis structure of the heavy vehicle can be effectively detected. Meanwhile, cooperating with the smaller scattering angle design (α=3°), the boundary of the high-energy ray beam is clearer, the penetrating ability is improved, the excellent irradiation precision and low scattering characteristics are still maintained, the application requirements in the specific high-strength detection scene are met, and the flexibility of the modular design of the application is embodied.

[0120] The above only describes the preferred embodiments of the present application and is not used to limit the present application. Any modification, equivalent replacement, improvement, etc. made within the spirit and principle of the present application shall be included in the protection scope of the present application.

[0121] In addition, the technical solutions of each embodiment can be combined with each other, but it must be based on the realization of the ordinary skilled in the art; when the combination of technical solutions appears contradictory or unachievable, it should be considered that the combination of technical solutions does not exist, nor is it within the protection scope required by the present application.

Claims

1. A cold cathode X-ray vehicle inspection transmitter box, characterized in that, It includes a transmitter housing (1), a transmitter unit (2) disposed within the transmitter housing (1), and an X-ray source (3) that provides X-rays to the transmitter unit; The X-ray source (3) includes a cold cathode X-ray tube (31) and a high-voltage power supply module. The cold cathode X-ray tube (31) and the high-voltage part of the high-voltage power supply module are immersed in high-voltage insulating oil and exchange heat with the outside through the outer shell of the X-ray source (3). The emitting unit (2) includes an emitting unit housing (21) and a filter assembly (22) disposed inside the emitting unit housing (21) and located in the beam output direction of the X-ray source (3). The outer shell (1) of the transmitter box is provided with a light guide strip (11), and the outer shell (21) of the transmitter unit is provided with a light outlet slit (211). The size and relative position of the light guide strip (11) and the light outlet slit (211) are matched with the geometric parameters of the target lane and the preset X-ray coverage range.

2. The cold cathode X-ray vehicle detection transmitter according to claim 1, characterized in that, The high-voltage power supply module adopts a distributed power supply module. The high-voltage components of the high-voltage power supply module are immersed in the high-voltage insulating oil and are electrically connected to the low-voltage control module located outside the oil through wires.

3. The cold cathode X-ray vehicle inspection transmitter according to claim 1, characterized in that, It also includes an open air bladder (4) connected to the oil cavity containing the high-voltage insulating oil, for discharging gas when the high-voltage insulating oil expands due to heat to maintain the pressure inside the oil cavity.

4. The cold cathode X-ray vehicle inspection transmitter according to claim 1, characterized in that, The cold cathode X-ray tube (31) is suspended and fixed inside the X-ray source (3).

5. The cold cathode X-ray vehicle inspection transmitter according to claim 1, characterized in that, The filter assembly (22) includes a fixed filter (221) and a movable filter (222); the fixed filter (221) is a groove structure formed on the outer shell (21) of the transmitting unit by mechanical processing; the movable filter (222) is a metal sheet that can be placed into the groove structure.

6. The cold cathode X-ray vehicle detection transmitter according to claim 5, characterized in that, The movable filter (222) is made of aluminum or copper, and is square in shape, with its side length matching the groove.

7. The cold cathode X-ray vehicle inspection transmitter according to claim 1, characterized in that, The inner side of the outer shell (21) of the transmitting unit is provided with a lead shielding liner (212).

8. The cold cathode X-ray vehicle inspection transmitter according to claim 1, characterized in that, It also includes a constant temperature and humidity system (5) installed inside the outer shell (1) of the launch box to maintain the ambient temperature inside the box.

9. An optical arrangement method for the cold cathode X-ray vehicle inspection transmitter box according to any one of claims 1-8, characterized in that, Includes the following steps: S1: Based on the lane width L, detector installation height Y0, and target vehicle tire height h, calculate the angle θ between the lower edge of the X-ray from the transmitter box and the horizontal direction. When the vehicle moves along the side of the road next to the transmitter box, θ is at its maximum, where θ = arctan((h-Y0) / L). S2: Determine the installation position of the cold cathode X-ray tube (31) such that the beam center line of the point forms an angle β with the lower edge of the X-ray, and β is not greater than the maximum beam angle £ of the X-ray tube; S3: Based on the geometric relationship determined in steps S1 and S2, calculate the installation position u of the transmitter box and the total length Z of the light guide strip (11); S4: Based on the results of step S3, calculate the installation position of the transmitting unit (2) in the box and the length D of the light output hole slit (211); S5: Based on the results of step S4, calculate the installation position of the X-ray source (3) in the emission unit (2) and the square side length n corresponding to its light outlet.

10. The optical arrangement method according to claim 9, characterized in that, Based on the preset X-ray scattering angle α, the width i of the light-emitting aperture (211) and the width j of the light guide strip (11) are calculated respectively, wherein: i=2×e×tanα, j=2×a×tanα, e is the distance from the position of the X-ray tube to the inner edge of the aperture, a is the distance from the position of the X-ray tube to the inner edge of the light guide strip, and α is 2° to 5°.

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