Protective structure of micro-mark detection CT device and control method of protective structure
By using a labyrinthine protective structure with layered materials and a height-adjustable design, the problems of large footprint, difficult heat dissipation, and severe fluorescence interference in micro-trace detection CT devices have been solved, achieving efficient radiation shielding and heat dissipation, and improving detection accuracy and efficiency.
Patent Information
- Authority / Receiving Office
- CN · China
- Patent Type
- Applications(China)
- Current Assignee / Owner
- SHANDONG MEIHANLIN CONSTR GRP CO LTD
- Filing Date
- 2026-03-12
- Publication Date
- 2026-05-05
AI Technical Summary
In existing micro-trace detection CT devices, the labyrinth-style protective structure results in a large footprint, difficulty in heat dissipation, and severe fluorescence interference, which affects detection accuracy and efficiency.
The labyrinthine protective design employs a layered material structure, including lead, tin, copper, and aluminum layers, combined with a liftable and heat-conducting structure, to achieve stepwise absorption of radiation and effective heat dissipation.
It improves detection accuracy and efficiency, reduces fluorescence interference, minimizes thermal drift and artifacts, and is suitable for industrial cycle time requirements.
Smart Images
Figure CN121978139A_ABST
Abstract
Description
Technical Field
[0001] This invention belongs to the field of micro-detection technology, and relates to a micro-trace detection CT device, and more particularly to a protective device for the micro-trace detection device and its control method. Background Technology
[0002] In micro-trace detection CT, labyrinth shielding equipment faces three major technical challenges: inconvenient access, difficulty in internal heat dissipation, and interference from fluorescence in traditional lead layers, which severely restricts detection accuracy and efficiency. Regarding ease of access, labyrinth shielding relies on multiple reflections within the channel to achieve radiation attenuation; the longer the channel and the more bends, the better the shielding effect. However, this significantly increases the equipment's footprint and easily leads to material jamming, making it difficult to meet the time-per-second requirements of modern industry. On the other hand, simplifying the channel structure fails to meet the shielding effectiveness of the GBZ117 standard, creating an irreconcilable design contradiction.
[0003] Internal heat dissipation is also a significant challenge. Labyrinth-style shielding is typically designed as a sealed structure to ensure shielding performance, lacking effective heat dissipation measures. Microfocus X-ray tubes (especially transmission targets) have extremely high power densities, resulting in significant local temperatures at the focal point. In addition, the detector and motor driver continuously generate heat, leading to a continuous accumulation of heat. Even granite bases with good thermal inertia will experience micron-level thermal expansion due to continuous temperature increases, causing thermal drift, inconsistent projection data, and severe imaging artifacts. Traditional air cooling requires openings, which pose risks of radiation and noise leakage.
[0004] Furthermore, traditional labyrinth-style shielding often uses a single lead layer as the shielding material. While this effectively attenuates the main X-ray beam, the interaction of high-energy photons with lead atoms excites inner-shell electrons, which emit characteristic X-ray fluorescence with energies of approximately 72-88 keV during de-excitation. Because micro-trace detection detectors are extremely sensitive, this fluorescence forms a "background fog" on the detector, significantly reducing the signal-to-noise ratio and contrast resolution of the image. For detection needs such as finding subtle density differences like microcracks in carbon fiber composites or defects in lithium battery separators, this background noise may completely drown out the tiny defect signal, affecting detection accuracy.
[0005] Therefore, it is necessary to design a protective structure and control method for a micro-trace detection CT device to solve the problems in the existing technology. Summary of the Invention
[0006] The purpose of this invention is to provide a protective structure and control method for a micro-trace detection CT device to solve the technical problems in the prior art.
[0007] To achieve the above objectives, the present invention adopts the following technical solution: On one hand, a protective structure for a micro-trace detection CT device is provided, including a first cover, a second cover, a third cover, a pit, a lifting mechanism, a base plate, a base, a vibration isolation mechanism, and bearings; the first cover, the second cover, and the third cover are nested concentrically and coaxially; the first cover is the innermost cover, which is installed on the base via the vibration isolation mechanism, and the base is installed inside the pit, forming a detection space, in which the X-ray micro-trace detection device is embedded; the second cover is placed outside the first cover, and its bottom is rotatably installed on the base plate via bearings, the base plate is installed in the pit via the lifting mechanism, and the rotation mechanism is installed on the base plate to drive the second cover to rotate; the third cover is placed outside the second cover, and its bottom is fixedly installed on a plate structure in the pit; the wall thickness of the top wall and bottom plate of the first cover, the top wall of the second cover, and the top wall of the third cover is uniform, while the wall thickness of the cylindrical sidewalls of the first cover, the second cover, and the third cover is non-uniform.
[0008] Preferably, the first cover, the second cover, and the third cover are layered material structures, with the innermost layer being a lead material layer, which constitutes the main structure of the cover; the inner and outer sides of the lead material layer are tin material layers; the outer side of the tin material layer is covered with a copper material layer; and the outer side of the copper material layer is covered with an aluminum material layer.
[0009] Preferably, the cylindrical sidewall of the first cover has a smaller thickness at the top and a larger thickness at the bottom, the second cover has a larger thickness at the top and a smaller thickness at the bottom, and the third cover has a smaller thickness at the top and a larger thickness at the bottom. A wedge-shaped fitting structure is formed between the outer side of the first cover and the inner side of the second cover, and a wedge-shaped fitting structure is formed between the outer side of the second cover and the inner side of the third cover. Both the inner side of the first cover and the outer side of the third cover are vertical cylindrical surfaces.
[0010] Preferably, a flow channel for coolant flow is formed between the copper material layer and the aluminum material layer. A groove with a cold-rolled semi-circular cross-section is provided on the outer side of the copper material layer, and a groove with a cold-rolled semi-circular cross-section is provided on the inner side of the aluminum material layer at a relatively opposite position. The grooves one and two merge to form the flow channel.
[0011] Preferably, the flow channels are divided into transverse flow channels and longitudinal flow channels, which are interconnected to form a grid pattern and distributed on the inner and outer surfaces of the cover structure.
[0012] Preferably, the flow channels inside the housing and the flow channels outside the housing are connected to form a cooling circuit, and a pump is installed on the circuit to pump the coolant in the flow channels from the inside of the housing to the outside of the housing.
[0013] Preferably, the second cover is adjustable relative to the first and third covers, and the second cover has two working positions: a low position and a high position.
[0014] Preferably, when the second cover is in a low position, the outer side of the first cover and the inner side of the second cover are in contact, and the outer side of the second cover and the inner side of the third cover are in contact.
[0015] Preferably, when the second cover is in a high position, the first cover, the second cover, and the third cover are out of contact, and there is a first gap and a second gap.
[0016] On the other hand, a control method for the protective structure of the aforementioned micro-trace detection CT device is provided, including: During the process of placing or removing the workpiece into or from the protective structure, the micro-trace detection CT device stops and lowers the position of the second cover through the lifting mechanism, so that the outer side of the first cover and the inner side of the second cover come into contact, and the outer side of the second cover and the inner side of the third cover come into contact. When the micro-trace detection CT device is in detection mode, the second cover is raised to a high position by the lifting mechanism.
[0017] The beneficial effects of this invention are: The three enclosures and three entrance channels form a labyrinthine protective structure. Radiation is attenuated by multiple reflections between the first gap C1 and the second gap C2 between the three enclosures. The design of the three enclosures and the lifting design of the middle enclosure ensure both the shielding requirements of the labyrinthine protective channels and the heat dissipation requirements of the labyrinthine protective structure, increasing the heat conduction efficiency between the three enclosures.
[0018] The layered structure design of this invention enables radiation to be absorbed through a "stepwise absorption" physical mechanism. This involves stacking a series of materials with decreasing atomic numbers, ensuring that each layer effectively absorbs the high-energy fluorescence generated by the previous layer, while its own fluorescence energy is low enough to be completely absorbed by the next layer or air. Ultimately, compared to bare lead shielding, the Pb-Sn-Cu-Al gradient structure effectively reduces the low-energy scattering background at the detector, improving the dynamic range of the micro-trace detection system and the visibility of minute defects.
[0019] The design of the liftable enclosure, heat-conducting structure, and uneven wall thickness enables the labyrinthine protective structure to effectively dissipate heat while ensuring shielding performance, avoiding continuous heat accumulation, reducing the effects of thermal drift and artifacts, and avoiding the radiation and noise leakage risks of traditional air cooling. Attached Figure Description
[0020] Figure 1 This is a schematic diagram of the protective longitudinal structure of the micro-trace detection CT device of the present invention; Figure 2 This is a top sectional view of the protective structure of the micro-trace detection CT device of the present invention; Figure 3This is another top sectional view of the protective structure of the micro-trace detection CT device of the present invention; Figure 4 This is a schematic diagram of the protective structure rotation mechanism of the micro-trace detection CT device of the present invention; Figure 5 This is a schematic diagram of the layered structure of the cover material of the present invention; Figure 6 This is a schematic diagram of the second cover of the present invention in a low position. Figure 7 This is a schematic diagram of the second cover of the present invention in a high position structure; Figure 8 This is a schematic diagram of the cooling flow channel of the present invention; Figure 9 This is a schematic diagram of the flow channel structure of the present invention; In the figure, the meanings of the reference numerals are as follows: 1 - First cover, 1a - First inlet channel, 1b - Base plate, 1c - Wiring space, 1d - Lead material layer, 1f - Tin material layer; 2 - Second cover, 2a - Second inlet channel, 2b - Bearing ring, 2c - Gear ring; 3 - Third cover, 3a - Third inlet channel; 4 - Foundation pit; 5 - Lifting mechanism; 6 - Base plate; 7 - Rotating mechanism, 7a - Gear, 7b - Gearbox; 8 - Base; 9 - Vibration isolation mechanism; 10 - Bearing, 10a - Upper bearing ring, 10b - Lower bearing ring; 11 - Aluminum material layer, 11a - Groove II; 12 - Copper material layer, 12a - Groove I; 13 - Flow channel, 13a - Transverse flow channel, 13b - Longitudinal flow channel; 14 - Pump; 15 - Cooling circuit; C1 - First gap, C2 - Second gap; A - Inner side of the first cover, B - Outer side of the first cover, C - Inner side of the second cover, D - Outer side of the second cover, E - Inner side of the third cover, F - Outer side of the third cover. Detailed Implementation
[0021] To enable those skilled in the art to better understand the technical solutions in the embodiments of this specification, the technical solutions in the embodiments of this specification will be described in detail below with reference to the accompanying drawings. Obviously, the described embodiments are only a part of the embodiments of this specification, and not all of the embodiments. Based on the embodiments in this specification, all other embodiments obtained by those skilled in the art should fall within the scope of protection.
[0022] like Figure 1-4The diagram shows the protective structure of the micro-trace detection CT device of the present invention. It includes a first cover 1, a second cover 2, a third cover 3, a base pit 4, a lifting mechanism 5, a base plate 6, a rotating mechanism 7, a base 8, a vibration isolation mechanism 9, and a bearing 10.
[0023] The radiation protection structure is mainly composed of three concentric, coaxially nested cylindrical covers, namely the first cover 1, the second cover 2, and the third cover 3. The three covers are structurally compatible and tightly connected, presenting a regular cylindrical shape. This radiation protection structure is installed in a circular concrete pit 4, with a base 8 at the center of the pit 4, which is made of granite.
[0024] The first cover 1, being the innermost cover, has the smallest diameter and forms an inspection space within it. The micro-trace detection CT device is securely embedded within this inspection space. A first inlet channel 1a is formed on the cylindrical sidewall of the first cover 1. A base plate 1b is fixed to the bottom of the first cover 1. The base plate 1b and the interior of the cylindrical sidewall of the first cover 1 form its inspection space. The micro-trace detection CT device is fixedly installed on the base plate 1b. The first inlet channel 1a connects the inspection space and the external space. The workpiece to be inspected is fed into the micro-trace detection CT device within the inspection space through the first inlet inspection channel 1a. A vibration isolation mechanism 9 is installed at the bottom of the base plate 1b and is fixedly mounted on the granite base 8.
[0025] The vibration isolation mechanism 9 adopts an air isolation structure, which mainly consists of an upper load-bearing plate, a lower load-bearing plate, an air spring assembly, and a sealing and protective mechanism. The upper load-bearing plate is fixedly installed at the bottom of the base plate 1b, and the bottom of the lower load-bearing plate is fixedly installed at the top of the base 8. Both the upper and lower load-bearing plates are made of high-strength steel plates. The air spring assembly is arranged between the two load-bearing plates and uses a sealed rubber airbag filled with high-pressure dry air. The airbag wall is reinforced with multiple layers. In addition, the structure is equipped with a pressure regulating device, which can precisely adjust the air pressure inside the airbag according to the load size to ensure stable vibration isolation effect and stable support for the first housing 1. The sealing and protective mechanism wraps around the outside of the air spring to prevent dust and moisture corrosion. The vibration isolation mechanism 9 supports the first housing 1 on the base 8 and isolates the vibration transmitted from the pit 4 and the base 8 to the first housing 1, thereby reducing artifacts of the micro-trace detection CT device and improving detection accuracy.
[0026] In addition, such as Figure 4 As shown, the bottom of the cylindrical sidewall of the first enclosure 1 extends downward from the base plate 1b by a certain distance, and the inner surface of this sidewall forms a wiring space 1c with the outer peripheral surface of the vibration isolation mechanism 9. The conduit leading out from the inside of the first enclosure 1 can be led out from the wiring space 1c through the perforation of the base plate 1b, thereby avoiding the need to open holes in the sidewall of the first enclosure 1 and reducing the risk of radiation leakage.
[0027] The diameter of the second cover 2 is slightly larger than that of the first cover 1. Its inner wall matches the outer wall of the first cover 1 and is fitted onto the outside of the first cover 1. A first gap C1 is formed between the inner wall of the second cover 2 and the outer wall of the first cover 1. The bottom of the second cover 2 is rotatably mounted on the base plate 6 via a bearing 10. The bottom of the base plate 6 is vertically mounted inside the pit 4 via a lifting mechanism 5.
[0028] like Figure 4 As shown, a support ring 2b is provided on the inner side of the bottom of the second cover 2. The support ring 2b is a stepped structure that protrudes inward from the inner wall of the second cover 2. The support ring 2b is located at the bottom of the first cover 1, and a first gap C1 is formed between the top of the support ring 2b and the bottom of the first cover 1.
[0029] The bearing 10 includes an upper bearing ring 10a, a lower bearing ring 10b, and a plurality of rollers located between the upper bearing ring 10a and the lower bearing ring 10b. The upper bearing ring 10a is fixedly embedded in the bottom of the bearing ring 2b, and the lower bearing ring 10b is fixedly mounted on the top of the base plate 6.
[0030] The base plate 6 is a circular steel plate, with a central through hole fitted onto the outside of the base 8. The bottom of the base plate 6 is fixedly installed on the top of the lifting mechanism 5, and the bottom of the lifting mechanism 5 is fixedly installed inside the pit 4. The lifting mechanism 5 is a multi-screw lifting mechanism. The synchronous lifting structure of this multi-screw lifting mechanism uses a central bevel gear as its core component. The central bevel gear is fixedly installed on a fixed shaft in the middle of the mechanism, and its outer circumference is evenly meshed with multiple driven bevel gears. The number of driven bevel gears is consistent with the number of screw lifting mechanisms and corresponds one-to-one. Each driven bevel gear is fixedly fitted onto the lower end of the screw of the corresponding screw lifting mechanism. The screw is arranged vertically, and its outer side is equipped with a nut seat, which is fixedly connected to the external bearing structure. The above-mentioned lifting mechanism 5 is prior art and will not be described in detail here. This lifting mechanism 5 supports the second cover 2 to achieve a small degree of rise and fall relative to the first cover 1.
[0031] A rotating mechanism 7 is also provided on the substrate 6. For example... Figure 4 As shown, a gear ring 2c is provided at the bottom of the side wall of the second cover 2, and a plurality of rotating mechanisms 7 are provided on the base plate 6 relative to the periphery of the second cover 2. The rotating mechanism 7 includes a gear 7a and a reduction motor 7b. The reduction motor 7b is fixedly mounted on the base plate 6, and its output shaft is fixedly mounted with the gear 7a, which meshes with the gear ring 2c of the second cover 2. Since the second cover 2 is rotatably mounted on the base plate 6 via bearings, the plurality of rotating mechanisms 7 synchronously drive the second cover 2 to rotate coaxially with respect to the first cover 1.
[0032] The third cover 3 is the outermost cover, and its inner wall is adapted to the outer wall of the second cover 2, forming a second gap C2 between the third cover 3 and the outer wall of the second cover 2. The bottom of the third cover 3 is fixedly installed on the plate structure on the foundation pit 4.
[0033] The second cover 2 and the third cover 3, at the same position relative to the first cover 1, respectively have a second entrance channel 2a and a third entrance channel 3a, which are the same size as the first entrance channel 1a. For example... Figure 2 , 3 This is a cross-sectional schematic diagram of the three enclosure structures. Since the first enclosure 1 and the third enclosure 3 are fixedly installed, the positions of the first entrance channel 1a and the third entrance channel 3a remain unchanged. The second enclosure 2 can rotate coaxially relative to the first enclosure 1 and the third enclosure 3, and the second enclosure 2 has an opening position (e.g., Figure 2 (as shown) and closing station (such as) Figure 3 As shown). Figure 2 As shown, when the second enclosure 2 is located at the door opening station, the first entrance channel 1a, the second entrance channel 2a, and the third entrance channel 3a are in phase. The detection space inside the first enclosure 1 is directly connected to the outside through the first entrance channel 1a, the second entrance channel 2a, and the third entrance channel 3a. The staff can directly place the workpiece to be detected onto the micro-trace detection CT device inside the first enclosure 1.
[0034] After the workpiece is stably installed in place, the rotating mechanism 7 drives the second cover 2 to rotate 180°, as follows: Figure 3 As shown, the second entrance channel 2a rotates to a position where the angle between its position and the positions of the first entrance channel 1a and the third entrance channel 3a is 180°. When the micro-trace detection CT device inside the first housing 1 is working, a labyrinthine protective structure is formed between the three housings and the three entrance channels. The radiation is attenuated by multiple reflections between the first gap C1 and the second gap C2 between the three housings. The design of the three housings and the rotation design of the middle housing ensure both the shielding requirements of the labyrinthine protective channel and the convenient entry of workpiece materials, adapting to the requirements of industrial cycle time.
[0035] The shielding materials of the three enclosures will be described below.
[0036] Traditional labyrinth-style shielding typically uses a single lead layer as the shielding material. While this effectively attenuates the main X-ray beam, the interaction of high-energy photons with lead atoms excites inner-shell electrons, which emit characteristic X-ray fluorescence with energies of approximately 72-88 keV during de-excitation. Because micro-trace detection detectors are extremely sensitive, this fluorescence forms a "background fog" on the detector, significantly reducing the signal-to-noise ratio and contrast resolution of the image. For detection needs such as finding subtle density differences like microcracks in carbon fiber composites or defects in lithium battery separators, this background noise can completely drown out the minute defect signal, affecting detection accuracy.
[0037] like Figure 5 The image shown is a partial longitudinal cross-sectional view of the cylindrical sidewall of the first cover 1 of the present invention, illustrating the material structure of the three covers of the present invention. For ease of explanation, Figure 5 Side A represents the inner side of the first shield 1, i.e., the side forming the detection space; side B represents the outer side of the first shield 1. In the material structure, the innermost layer is a lead material layer 1d, which constitutes the main structure of the shield. Tin material layers 1f are located on both the inner and outer sides of the lead material layer 1d. A copper material layer 12 is wrapped around the outside of the tin material layer 1f. An aluminum material layer 11 is wrapped around the outside of the copper material layer 12. In the above-mentioned layered structure, the lead material layer 1d is the thickest, constituting the main supporting structure of the shield, and its thickness is designed according to radiation protection requirements. The tin material layer 1f is a layered structure composed of tin plates. The copper material layer 12 and the aluminum material layer 11 are made of thin copper plates and thin aluminum plates, respectively.
[0038] The mechanism by which the above-mentioned layered materials reduce background noise is explained below.
[0039] First, the lead material layer 1d, as the innermost layer, is responsible for blocking the vast majority of the primary X-ray beam. Tin material layers 1f, located on both sides of the lead material layer 1d, are tightly attached to the inner side of the lead layer. Since the K absorption edge of tin is approximately 29.2 keV, although it cannot efficiently absorb the 88 keV fluorescence of lead (this is mainly due to the thickness margin of lead itself), it can effectively absorb the L-series fluorescence and some scattered rays produced by lead. More importantly, the fluorescence energy generated by the tin layer after excitation is approximately 25-29 keV, which is much lower than the fluorescence of lead. A copper material layer 12, covering the outside of the tin material layer 1f, is tightly attached to the inner side of the tin layer. Copper can efficiently absorb the 25-29 keV fluorescence generated by tin. The fluorescence energy generated by copper after excitation is approximately 8-9 keV. An aluminum material layer 11, covering the outside of the copper material layer 12, serves as the outermost layer. Aluminum can completely absorb the 8-9 keV fluorescence generated by copper. Aluminum itself produces extremely low fluorescence energy (approximately 1.5 keV), which is attenuated after traveling a very short distance in air and is typically below the energy threshold of the detector or filtered out by the detector window. The layered structure design of this invention enables radiation to be absorbed through a "stepwise absorption" physical mechanism. This involves stacking a series of materials with decreasing atomic numbers, allowing each layer to effectively absorb the high-energy fluorescence produced by the previous layer, while its own fluorescence energy is low enough to be completely absorbed by the next layer or by the air. Ultimately, compared to bare lead shielding, the shielding using a Pb-Sn-Cu-Al gradient structure effectively reduces the low-energy scattering background at the detector, improving the dynamic range of the micro-trace detection system and the visibility of minute defects.
[0040] The aforementioned layered material design is applied to the circumferential sidewalls, top wall, and bottom plate 1b of the first cover 1, the circumferential sidewalls and top wall of the second cover 2, and the circumferential sidewalls and top wall of the third cover 3.
[0041] Furthermore, in one embodiment, the wall thicknesses of the circumferential sidewalls, top wall, and bottom plate 1b of the first cover 1, the circumferential sidewalls and top wall of the second cover 2, and the circumferential sidewalls and top wall of the third cover 3 are uniform.
[0042] In one embodiment, a flow channel 13 for coolant flow is formed between the copper material layer 12 and the aluminum material layer 11. Figure 5 As shown, a cold-rolled semi-circular cross-section groove 12a is provided on the outer side of the copper material layer 12, and a cold-rolled semi-circular cross-section groove 11a is provided on the inner side of the aluminum material layer 11 at a relatively opposite position. The first groove 12a and the second groove 11a merge to form a flow channel 13. Figure 9 As shown, the flow channel 13 is divided into a transverse flow channel 13a and a longitudinal flow channel 13b. The transverse flow channel 13a and the longitudinal flow channel 13b are interconnected to form a grid, which is distributed on the inner and outer surfaces of the cover structure.
[0043] In one embodiment, such as Figure 5 , 8 As shown, taking the first housing 1 as an example, the inner flow channel 13 and the outer flow channel 13 are connected to form a cooling circuit 15. A pump 14 is installed on the circuit, and the pump 14 pumps the coolant in the flow channel 13 from the inside of the housing to the outside of the housing. The coolant absorbs the heat generated by the X-ray detection device through the copper-aluminum metal layer structure constituting the flow channel 13 inside the housing. Then, the coolant is pumped by the pump 14 into the flow channel 13 on the outside of the housing, and conducts the absorbed heat to the copper-aluminum metal layer on the outside of the housing.
[0044] In another embodiment, in order to better conduct heat from the first cover 1 to the second cover 2 and the third cover 3 in sequence, the wall thickness of the top wall of the first cover 1, the bottom plate 1b, the top wall of the second cover 2, and the top wall of the third cover 3 is uniform, while the wall thickness of the cylindrical sidewalls of the first cover 1, the second cover 2, and the third cover 3 is non-uniform.
[0045] Specifically, such as Figure 6 As shown, the cylindrical sidewall of the first cover 1 has a thinner wall at the top and a thicker wall at the bottom, the second cover 2 has a thicker wall at the top and a thinner wall at the bottom, and the third cover 3 has a thinner wall at the top and a thicker wall at the bottom. This creates a wedge-shaped fit between the outer side (B) of the first cover 1 and the inner side (C) of the second cover 2, and also between the outer side (D) of the second cover 2 and the inner side (E) of the third cover 3. Furthermore, for ease of assembly and transportation, the inner side (A) of the first cover 1 and the outer side (F) of the third cover 3 are both vertical cylindrical surfaces.
[0046] As described above, the second cover 2 is vertically adjustable relative to the first cover 1 and the third cover 3, and the second cover 2 has the following characteristics: Figure 6 The lower bits shown are as follows Figure 7 The high position is shown. For example... Figure 6As shown, when the second cover 2 is in a low position, the outer side B of the first cover 1 and the inner side C of the second cover 2 are in contact. Specifically, this can be the contact of the metal arc-shaped surfaces of the corresponding flow channels 13. At this time, the copper-aluminum metal plate on the outer side of the first cover 1 can conduct heat to the copper-aluminum metal plate on the inner side of the second cover 2. Similarly, the flow channels 13 on the second cover 2 conduct heat from its interior to its outer side D. At this time, the outer side D of the second cover 2 and the inner side E of the third cover 3 are in contact, specifically the contact of the metal arc-shaped surfaces of the corresponding flow channels 13. Likewise, the flow channels 13 on the third cover 3 conduct heat from its inner side E to its outer side F. Finally, the heat inside the first cover 1 is conducted step by step to the external space, reducing the heat accumulation inside the labyrinth-type shielding structure. This step-by-step heat conduction process specifically occurs when the micro-trace detection CT device is in a non-detection state, preventing the contact of the covers from causing external vibrations to be conducted to the micro-trace detection CT device. In actual production cycle, the process of heat conduction in stages can occur during the process of placing or removing the workpiece into or from the protective structure. That is, during the process of placing or removing the workpiece into or from the protective structure, the position of the second cover 2 is lowered by the lifting mechanism 5 so that the outer side B of the first cover 1 and the inner side C of the second cover 2 come into contact, and the outer side D of the second cover 2 and the inner side E of the third cover 3 come into contact.
[0047] like Figure 3 As shown, when the micro-trace detection CT device is in detection mode, the second cover 2 is raised to a high position by the lifting mechanism 5. The first cover 1, the second cover 2, and the third cover 3 are no longer in contact, with a first gap C1 and a second gap C2. At this time, heat can still be conducted from the first cover 1 through the air in the first gap C1 to the second cover 2, and then through the second gap C2 to the third cover 3. However, the heat conduction efficiency is not as high as when the second cover 2 is in a low position.
[0048] Through the design of the liftable cover, heat-conducting structure and uneven wall thickness, the labyrinth-style protective structure can effectively dissipate heat while ensuring shielding performance, avoiding the continuous accumulation of heat, reducing the effects of thermal drift and the generation of artifacts, and avoiding the radiation and noise leakage risks of traditional air cooling.
[0049] The above description is merely a specific implementation of the embodiments of this specification. It should be noted that for those skilled in the art, several improvements and modifications can be made without departing from the principles of the embodiments of this specification, and these improvements and modifications should also be considered within the protection scope of the embodiments of this specification.
Claims
1. A protective structure for a micro-trace detection CT device, characterized in that: The system includes a first cover, a second cover, a third cover, a pit, a lifting mechanism, a base plate, a base, a vibration isolation mechanism, and bearings. The first cover, second cover, and third cover are nested concentrically and coaxially. The first cover is the innermost cover and is mounted on the base via the vibration isolation mechanism. The base is installed inside the pit, forming a detection space within which an X-ray micro-trace detection device is embedded. The second cover is placed outside the first cover and is rotatably mounted on the base plate via bearings. The base plate is mounted inside the pit via the lifting mechanism, and a rotating mechanism mounted on the base plate drives the second cover to rotate. The third enclosure is placed outside the second enclosure, and its bottom is fixedly installed on the plate structure on the foundation pit; the wall thickness of the top wall and bottom plate of the first enclosure, the top wall of the second enclosure, and the top wall of the third enclosure are uniform, while the wall thickness of the cylindrical side walls of the first enclosure, the second enclosure, and the third enclosure are not uniform.
2. The protective structure of the micro-trace detection CT device according to claim 1, characterized in that: The first, second, and third covers are layered material structures. The innermost layer is a lead material layer, which constitutes the main structure of the cover. The lead material layer is surrounded by tin material layers on both the inside and outside. The tin material layer is covered by a copper material layer on the outside. The copper material layer is covered by an aluminum material layer on the outside.
3. The protective structure of the micro-trace detection CT device according to claim 2, characterized in that: The cylindrical sidewall of the first cover has a smaller thickness at the top and a larger thickness at the bottom, the second cover has a larger thickness at the top and a smaller thickness at the bottom, and the third cover has a smaller thickness at the top and a larger thickness at the bottom. A wedge-shaped fit structure is formed between the outer side of the first cover and the inner side of the second cover, and a wedge-shaped fit structure is also formed between the outer side of the second cover and the inner side of the third cover. The inner side of the first cover and the outer side of the third cover are both vertical cylindrical surfaces.
4. The protective structure of the micro-trace detection CT device according to claim 3, characterized in that: A flow channel for coolant is formed between the copper material layer and the aluminum material layer. A groove with a cold-rolled semi-circular cross-section is provided on the outer side of the copper material layer, and a groove with a cold-rolled semi-circular cross-section is provided on the inner side of the aluminum material layer at a relatively opposite position. The grooves one and two merge to form the flow channel.
5. The protective structure of the micro-trace detection CT device according to claim 4, characterized in that: The flow channels are divided into transverse flow channels and longitudinal flow channels. The transverse and longitudinal flow channels are interconnected to form a grid, which is distributed on the inner and outer surfaces of the cover structure.
6. The protective structure of the micro-trace detection CT device according to claim 5, characterized in that: The flow channels inside and outside the enclosure are connected to form a cooling circuit. A pump is installed on the circuit to pump the coolant in the flow channels from the inside of the enclosure to the outside of the enclosure.
7. The protective structure of the micro-trace detection CT device according to claim 6, characterized in that: The second cover can be raised and lowered relative to the first and third covers, and has two working positions: a low position and a high position.
8. The protective structure of the micro-trace detection CT device according to claim 7, characterized in that: When the second cover is in a low position, the outer side of the first cover and the inner side of the second cover are in contact, and the outer side of the second cover and the inner side of the third cover are in contact.
9. The protective structure of the micro-trace detection CT device according to claim 8, characterized in that: When the second cover is in a high position, the first cover, the second cover, and the third cover are no longer in contact, and there is a first gap and a second gap.
10. A control method for the protective structure of the micro-trace detection CT device as described in claim 9, characterized in that: include: During the process of placing or removing the workpiece into or from the protective structure, the micro-trace detection CT device stops and lowers the position of the second cover through the lifting mechanism, so that the outer side of the first cover and the inner side of the second cover come into contact, and the outer side of the second cover and the inner side of the third cover come into contact. When the micro-trace detection CT device is in detection mode, the second cover is raised to a high position by the lifting mechanism.