A quasi-optical cavity-based dielectric property separation cylindrical resonator for powder materials

Abstract

The application relates to the technical field of resonant cavities, in particular to a powder material dielectric property separation type cylindrical resonant cavity based on a quasi-optical cavity, which comprises a box body, an upper cavity, a sample bin and a lower cavity are arranged in the box body, the upper cavity is in a cylindrical structure, the material of the sample bin is flexible polytetrafluoroethylene, magnetic attraction points are respectively arranged on the top and the bottom of the sample bin, the top of the sample bin is magnetically connected with the upper cavity, and the bottom of the sample bin is magnetically connected with the lower cavity; the lower cavity is in a cylindrical structure, a heat insulation sleeve is arranged on the surface of the lower cavity, and a wave-absorbing material layer is attached to the inner wall of the lower cavity; the diamond coating has superhard characteristics and extremely low surface roughness, can significantly reduce the scattering loss of electromagnetic waves on the inner wall of the cavity, can quickly dissipate the heat generated by electromagnetic energy in the cavity, and can inhibit the influence of temperature fluctuation on the Q value; the cavity is divided into three parts, i.e. an upper part, a middle part and a lower part, and is connected through the magnetic attraction points to form a modular quasi-optical cavity, and in combination with the wave-absorbing material layer and high-precision processing, single-mode purity can be realized.

Description

Technical Field

[0001] This invention relates to the field of resonant cavity technology, and in particular to a cylindrical resonant cavity based on quasi-optical cavity and dielectric properties of powder material. Background Technology

[0002] The resonant cavity is a core component in high-frequency technology and acoustics! The core conclusion is: the resonant cavity constrains specific waves through boundaries, causing them to form standing waves and resonate within the cavity, thereby concentrating energy and filtering specific frequencies; the resonant cavity combines the low-loss broadband characteristics of the quasi-optical cavity with the sample compatibility of the split cylindrical structure, and by measuring the changes in the resonant parameters within the cavity, the dielectric constant and dielectric loss of the powder material can be inferred.

[0003] Existing technologies mostly use single oxygen-free copper or ordinary metal materials without optimizing the surface coating design. The high surface roughness of the cavity wall easily leads to electromagnetic wave scattering loss; the heat generated by electromagnetic loss cannot be quickly dissipated, resulting in an increase in cavity temperature and a significant decrease in Q value. Summary of the Invention

[0004] The purpose of this invention is to provide a cylindrical resonant cavity based on a quasi-optical cavity and a powder material dielectric property separation method, which addresses the shortcomings of existing technologies.

[0005] To achieve the above objectives, the technical solution of the present invention is as follows:

[0006] A cylindrical resonant cavity based on quasi-optical cavity for separating the dielectric properties of powder materials includes a housing, which contains an upper cavity, a sample chamber, and a lower cavity.

[0007] The upper cavity has a cylindrical structure and is made of oxygen-free copper. The inner wall of the upper cavity has a polished surface with a surface roughness Ra≤0.1μm. The polished surface is electroplated with a 50nm thick nanodiamond coating. The bottom of the upper cavity is connected to the sample chamber.

[0008] The sample chamber includes a cylindrical hollow cavity made of flexible polytetrafluoroethylene. The inner wall of the cavity is coated with a 10μm thick hydrophobic nano-coating. An elastic pressure ring is installed at the top of the cavity, and a pressure sensor is installed at the bottom. Magnetic attraction points are installed at the top and bottom of the sample chamber. The top of the sample chamber is magnetically connected to the upper cavity, and the bottom of the sample chamber is magnetically connected to the lower cavity. The lower cavity is a cylindrical structure with a heat insulation sleeve on its surface, and a wave-absorbing material layer is attached to the inner wall of the lower cavity.

[0009] Furthermore: a guide opening is provided at the bottom of the housing, and a first drive plate, a second drive plate, and a third drive plate are hinged to the guide opening. The first drive plate, the second drive plate, and the third drive plate are respectively surrounding the periphery of the housing. The first drive plate, the second drive plate, and the third drive plate can swing to block the guide opening. A first sensing device is installed on the first drive plate, a second sensing device is installed on the second drive plate, and a third sensing device is installed on the third drive plate. The first drive plate and the second drive plate include a first plate body, and the two first plate bodies are arranged opposite each other. The housing is provided with a first swing drive mechanism that drives the first plate body to swing longitudinally and a second swing drive mechanism that drives the third drive plate to swing longitudinally.

[0010] Furthermore: the first swing drive mechanism includes two spaced-apart first drive modules. Each first drive module includes a longitudinal rack arranged longitudinally on the housing. A rotatable first drive gear is installed on the side wall of the housing. The first drive gear meshes with the longitudinal rack for transmission. The first drive gear is mounted with a synchronously rotating first drive shaft. A second drive bevel gear is installed at the outer end of the first drive shaft. A third drive bevel gear that meshes with the second drive bevel gear is also installed on the side wall of the housing. A first synchronous pulley is coaxially mounted on the third drive bevel gear. A hinge structure is installed at the bottom of the housing. The hinge structure rotatably connects the first plate to the housing. A second synchronous pulley that cooperates with the first synchronous pulley is installed at the outer end of the hinge structure. A synchronous belt drives between the second synchronous pulley and the first synchronous pulley.

[0011] Furthermore: the housing is equipped with a first drive motor and a lead screw drive mechanism that is connected to the drive end of the first drive motor. The drive end of the lead screw drive mechanism is equipped with a transmission sleeve, which is connected to a longitudinal rack. The housing is formed with a longitudinally arranged transmission groove. A compression spring for buffering movement of the longitudinal rack is installed at the top of the transmission groove. The bottom of the compression spring is connected to the longitudinal rack. Laterally protruding sliding blocks are formed on both long sides of the longitudinal rack. A guide groove is formed along the length of the inner wall of the transmission groove. Guide balls that roll in cooperation with the guide groove are installed on the sliding blocks.

[0012] Furthermore: the hinge structure includes three transmission grooves formed on the three long sides of the bottom of the housing. A rotating shaft is installed in the transmission groove. One of the inner long sides of the first drive plate, the second drive plate, and the third drive plate is formed with a transmission plate embedded in the transmission groove. The transmission plate is fixedly connected to the rotating shaft. A part of the rotating shaft connected to the first plate is exposed outward. A second synchronous pulley is installed on the exposed part of the transmission shaft. A first torsion spring is provided in the transmission groove and sleeved on the transmission shaft. The torque force of the first drive motor is greater than the torque force of the first torsion spring. The elastic force of the first torsion spring can drive the rotating shaft to rotate and drive the first plate to swing outward.

[0013] Furthermore: the second swing drive mechanism includes two rotating wheels mounted on the outer side wall of the housing. The rotating wheels are wound with drive lines, and the outer ends of the drive lines are connected to the back of the third drive plate. The rotating wheels can rotate to wind or unwind the drive lines to drive the third drive plate to swing outward. A rotating shaft connected to the third drive plate is fitted with a second torsion spring. The torsion direction of the second torsion spring is opposite to that of the first torsion spring. The second torsion spring can drive the rotating shaft to rotate and drive the third drive plate to swing inward.

[0014] Furthermore: a fixed bracket is installed on the outer wall of the housing, and the fixed bracket is equipped with a variable frequency crane motor and a motor shaft. The drive end of the variable frequency crane motor is coaxially connected to the motor shaft, and the motor shaft is connected to the rotating wheel. A first guide wheel for guiding the drive line is also installed on the outer wall of the housing, and a second guide wheel for guiding the drive line is installed on the back of the third drive plate. The first guide wheel can move laterally, and the second guide wheel can move laterally in a direction perpendicular to the third drive plate.

[0015] Furthermore: an inclined auxiliary telescopic cylinder is also provided on the outer wall of the box, and a horizontally arranged drive linear module is provided on the outer wall of the box. A horizontal moving seat is installed on the drive end of the drive linear module, and the auxiliary telescopic cylinder is installed on the horizontal moving seat. The drive end of the auxiliary telescopic cylinder faces the bottom of the box, and a guide pressure block that contacts the drive end of the auxiliary telescopic cylinder is installed on the edge of the third drive plate.

[0016] Furthermore: the first drive board is equipped with a humidity sensor; the second drive board is equipped with an ambient temperature sensor; and the third drive board is equipped with a displacement sensor; the humidity sensor, ambient temperature sensor, and displacement sensor can be disassembled and replaced.

[0017] Furthermore: the outer wall of the box is formed with a side window, which is horizontally aligned with the sample chamber. The side window is hinged with a side door that can swing longitudinally. The side door is provided with a support rail along its length. The outer end of the sample chamber is equipped with a support sliding seat that slides with the support rail. A side top block is installed on the back of the side door.

[0018] The beneficial effects of this invention are as follows: The diamond coating possesses ultra-hard properties and extremely low surface roughness, significantly reducing the scattering loss of electromagnetic waves on the inner wall of the cavity. It can quickly dissipate the heat generated by electromagnetic energy within the cavity and suppress the influence of temperature fluctuations on the Q value. The cavity is divided into upper, middle, and lower parts, connected by magnetic attraction points to form a modular quasi-optical cavity. Combined with the absorbing material layer and high-precision processing, single-mode purity can be achieved, ensuring the accuracy of dielectric parameter calculations. The middle cavity is made of flexible PTFE material, whose low dielectric constant and low loss tangent minimize interference to the test signal. Simultaneously, the flexible material can adapt to the shape of powder particles, avoiding electric field distortion caused by uneven powder filling in rigid containers. The 10μm hydrophobic nano-coating on the inner wall of the middle cavity further prevents powder adsorption, ensuring sample reusability. Furthermore, the elastic pressure ring at the top of the middle cavity compensates for volume changes during powder compaction through elastic deformation, and the pressure sensor at the bottom monitors the pressure on the sample in real time. Attached Figure Description

[0019] Figure 1 This is a schematic diagram of a cylindrical resonant cavity.

[0020] Figure 2 This is a schematic diagram of the cross-sectional structure of the box.

[0021] Figure 3 This is a schematic diagram of the box structure viewed from below.

[0022] Figure 4 This is a schematic diagram of the structure of the first swing drive mechanism.

[0023] Figure 5 This is a schematic diagram of a hinged structure.

[0024] Figure 6 This is a schematic diagram of the structure where the third drive board is in a vertical position.

[0025] Figure 7 This is a schematic diagram of the structure when the third drive plate closes the guide opening.

[0026] The reference numerals in the figures include:

[0027] 1-Box,

[0028] 11-Upper cavity, 12-Sample chamber, 13-Lower cavity, 14-Middle cavity, 15-Elastic pressure ring

[0029] 16-Insulation sleeve, 17-Magnetic attachment point, 18-Side window, 19-Side opening door, 191-Support sliding seat,

[0030] 192-Side Top Block,

[0031] 2-Guide opening,

[0032] 21-First drive board, 22-Second drive board, 23-Third drive board, 24-First swing drive mechanism, 25-First drive module, 26-First drive motor, 27-Screw drive mechanism

[0033] 3-Transmission long slot,

[0034] 31-Longitudinal rack, 32-Compression spring, 33-Guide groove, 34-Sliding block, 35-First drive shaft

[0035] 36-First drive gear, 37-Second drive bevel gear, 38-Third drive bevel gear

[0036] 4- Hinged structure

[0037] 41-First synchronous pulley, 42-Second synchronous pulley, 43-Synchronous belt, 44-Rotating shaft, 45-Transmission groove

[0038] 46-Transmission plate, 47-First torsion spring,

[0039] 5-Second swing drive mechanism

[0040] 51-Rotating wheel, 52-Drive line, 53-Fixed bracket, 54-Variable frequency crane motor

[0041] 55-First guide wheel, 56-Second guide wheel, 57-Auxiliary telescopic cylinder

[0042] 58-Drive linear module, 59-Horizontal moving seat, 60-Guide pressure block, 61-First sensing device

[0043] 62-Second sensing device, 63-Third sensing device. Detailed Implementation

[0044] The present invention will now be described in detail with reference to the accompanying drawings.

[0045] like Figure 1-7 As shown, a cylindrical resonant cavity based on quasi-optical cavity and dielectric properties of powder materials is disclosed. It includes a housing 1, within which an upper cavity 11, a sample chamber 12, and a lower cavity 13 are disposed. The upper cavity 11 has a cylindrical structure and is formed from oxygen-free copper. The inner wall of the upper cavity 11 has a polished surface with a surface roughness Ra≤0.1μm, which is electroplated with a 50nm thick nanodiamond coating. The bottom of the upper cavity 11 is connected to the sample chamber 12. The diamond coating possesses ultra-hard properties and extremely low surface roughness, significantly reducing the scattering loss of electromagnetic waves on the inner wall of the cavity, rapidly dissipating the heat generated by electromagnetic energy within the cavity, and suppressing the influence of temperature fluctuations on the Q value.

[0046] The cavity is divided into three parts: upper, middle and lower, which are connected by magnetic attraction point 17 to form a modular quasi-optical cavity. Combined with the absorbing material layer and high-precision processing, single-mode purity can be achieved, ensuring the accuracy of dielectric parameter calculation.

[0047] The sample chamber 12 includes a cylindrical hollow cavity 14 made of flexible polytetrafluoroethylene (PTFE). The inner wall of the cavity 14 is coated with a 10 μm thick hydrophobic nano-coating. An elastic pressure ring 15 is installed at the top of the cavity 14, and a pressure sensor is installed at the bottom. Magnetic attraction points 17 are installed at the top and bottom of the sample chamber 12. The top of the sample chamber 12 is magnetically connected to the upper cavity 11, and the bottom of the sample chamber 12 is magnetically connected to the lower cavity 13. The cavity 14 is made of flexible PTFE, whose low dielectric constant and low loss tangent can minimize interference with the test signal. At the same time, the flexible material can adapt to the shape of powder particles, avoiding electric field distortion caused by uneven powder filling in rigid containers. The 10 μm hydrophobic nano-coating on the inner wall of the cavity 14 further prevents powder adsorption, ensuring sample reusability. In addition, the elastic pressure ring 15 at the top of the cavity 14 compensates for volume changes during powder compaction through elastic deformation, and the pressure sensor at the bottom monitors the pressure on the sample in real time.

[0048] The lower cavity 13 has a cylindrical structure with a heat insulation sleeve 16 covering its surface. An absorbing material layer is attached to the inner wall of the lower cavity 13. The heat insulation sleeve 16 reduces the impact of ambient temperature fluctuations on the cavity, ensuring that the test is conducted under constant temperature conditions. The absorbing material layer attached to the inner wall absorbs stray electromagnetic waves, increasing the internal reflection loss of the cavity to below -30dB and eliminating the influence of multipath interference on the dielectric constant calculation.

[0049] Furthermore, the sample chamber 12 is quickly connected to the upper and lower cavities 13 via magnetic attraction points 17, facilitating rapid disassembly and replacement of the sample chamber 12. The magnetic attraction points 17 can be made of high-temperature resistant permanent magnet materials, such as samarium-cobalt alloy, which maintains good adsorption force within a temperature range of -40℃ to 200℃, adapting to complex testing environments. This achieves high-precision measurement of all parameters and a wide frequency band of the dielectric properties of powder materials, representing a technological breakthrough.

[0050] Furthermore, the outer wall of the housing 1 is formed with a side window 18, which is laterally aligned with the sample chamber 12. The side window 18 is hinged to a side door 19 that can swing longitudinally. The side door 19 has a support rail arranged along its length. The outer end of the sample chamber 12 is equipped with a support sliding seat 191 that slides with the support rail. A side top block 192 is installed on the back of the side door 19. When testing lithium battery electrode powder, the side door 19 swings longitudinally through the hinge. The support rail arranged along the length direction cooperates with the support sliding seat 191 of the sample chamber 12, allowing the sample chamber 12 to move laterally. The operator can pull out the sample chamber 12 laterally through the side door 19 to quickly change the powder. In addition, after the side door 19 swings longitudinally to a straight position through the hinge, the side top block 192 located on the back of the side door 19 just abuts against the side wall of the housing 1, thereby supporting the side door 19, preventing it from falling, and maintaining a straight position for the sample chamber 12 to move, disassemble, and replace.

[0051] Specifically, since different powders require different targeted sensors for dielectric property testing, a guide opening 2 is provided at the bottom of the housing 1 to avoid damaging the cavity structure. The guide opening 2 is hinged to a first drive plate 21, a second drive plate 22, and a third drive plate 23. The first drive plate 21, second drive plate 22, and third drive plate 23 surround the periphery of the housing 1. The first drive plate 21, second drive plate 22, and third drive plate 23 can swing to block the guide opening 2. A first sensing device 61 is installed on the first drive plate 21, a second sensing device 62 is installed on the second drive plate 22, and a third sensing device 63 is installed on the third drive plate 23. The first drive plate 21 and second drive plate 22 each include a first plate body, which are arranged opposite each other. The housing 1 is provided with a first swing drive mechanism 24 that drives the first plate body to swing longitudinally, and a second swing drive mechanism 5 that drives the third drive plate 23 to swing longitudinally. The first sensing device 61, second sensing device 62, and third sensing device 63 are different sensors.

[0052] In this embodiment, when different powder properties need to be tested, the first swing drive mechanism 24 and the second swing drive mechanism 5 drive the corresponding first drive plate 21, second drive plate 22, and third drive plate 23 to swing inward, so that the drive plate is located at the bottom of the guide opening 2 and can be aligned with the powder in the sample chamber 12. When the resonant cavity tests the dielectric properties of the powder, the sensor can obtain the corresponding test data. There is no need to disassemble and replace the sensor, thereby improving the replacement efficiency and facilitating the testing of different types of powders.

[0053] Specifically, the first swing drive mechanism 24 includes two spaced-apart first drive modules 25. Each first drive module 25 includes a longitudinal rack 31 arranged longitudinally on the housing 1. A rotatable first drive gear 36 is installed on the side wall of the housing 1. The first drive gear 36 meshes with the longitudinal rack 31 for transmission. The first drive gear 36 is equipped with a synchronously rotating first drive shaft 35. The first drive shaft 35 is mounted on the side wall of the housing 1 via a bracket. A second drive bevel gear 37 is installed at the outer end of the first drive shaft 35. A third drive bevel gear 38 that meshes with the second drive bevel gear 37 is also installed on the side wall of the housing 1. A first synchronous pulley 41 is coaxially mounted on the third drive bevel gear 38. A hinge structure 4 is installed at the bottom of the housing 1. The hinge structure 4 rotatably connects the first plate to the housing 1. A second synchronous pulley 42 that cooperates with the first synchronous pulley 41 is installed at the outer end of the hinge structure 4. A synchronous belt 43 is connected between the second synchronous pulley 42 and the first synchronous pulley 41 for transmission. When the first drive plate 21 or the second drive plate 22 needs to be oscillated, the corresponding first drive module 25 works. Through the longitudinal movement of the longitudinal rack 31, and with the transmission of the first drive gear 36, the second drive bevel gear 37 and the third drive bevel gear 38, the first synchronous pulley 41 is rotated. Under the transmission of the synchronous belt 43, the second synchronous pulley 42 rotates synchronously, so as to drive the hinge structure 4 coaxially connected to the second synchronous pulley 42 to rotate, thereby realizing the oscillation of the first plate. The first plate can be flipped inward at the bottom of the guide opening 2 or flipped outward at the periphery of the guide opening 2.

[0054] In addition, the drive board adopts an oxygen-free copper substrate and a beryllium copper spring edge structure. When the drive board swings to block the guide opening 2, the spring fits tightly with the gold-plated sealing groove at the bottom of the housing 1, forming a metal-to-metal sealing structure. With the carbonyl iron powder absorbing layer on the inner wall of the drive board, the electromagnetic leakage in the guide opening 2 area can be suppressed to below -55dB, while reducing the temperature conduction loss, ensuring that the electromagnetic environment and thermal stability of the cavity are consistent before and after the sensor switching.

[0055] Furthermore, the housing 1 is equipped with a first drive motor 26 and a lead screw drive mechanism 27 that is connected to the drive end of the first drive motor 26. A transmission sleeve is installed at the drive end of the lead screw drive mechanism 27, and the transmission sleeve is connected to the longitudinal rack 31. The housing 1 has a longitudinally arranged transmission groove 3. A compression spring 32 for buffering the movement of the longitudinal rack 31 is installed at the top of the transmission groove 3. The bottom of the compression spring 32 is connected to the longitudinal rack 31. Laterally protruding sliding blocks 34 are formed on both long sides of the longitudinal rack 31. A guide groove 33 is formed along the length of the inner wall of the transmission groove 3. Guide balls that roll in cooperation with the guide groove 33 are installed on the sliding blocks 34. Under the transmission cooperation of the first drive motor 26 and the lead screw drive mechanism 27, the longitudinal rack 31 located in the transmission groove 3 moves with buffering, and the longitudinal rack 31 can mesh with the first drive gear 36 for transmission; thereby realizing the flipping of the first plate, i.e., the flipping of the first drive plate 21 or the second drive plate 22. When the longitudinal rack 31 moves up and down, it slides with the guide groove 33 through the sliding block 34 and guide ball, which further improves the movement stability of the longitudinal rack 31.

[0056] It should be noted that the first drive motor 26 is a permanent magnet synchronous servo motor.

[0057] Furthermore, the hinge structure 4 includes three transmission grooves 45 formed on the three long sides of the bottom of the housing 1. The transmission grooves 45 are equipped with rotating shafts 44. One of the inner long sides of the first drive plate 21, the second drive plate 22 and the third drive plate 23 are respectively formed with transmission plates 46 embedded in the transmission grooves 45. The transmission plates 46 are fixedly connected to the rotating shafts 44. A part of the rotating shafts 44 connected to the first plate is exposed outward. The second synchronous wheel 42 is installed on the exposed part of the transmission shaft. The transmission grooves 45 are provided with a first torsion spring 47 sleeved on the transmission shaft. The elastic force of the first torsion spring 47 can drive the rotating shaft 44 to rotate and drive the first plate to swing outward. The torque force of the first drive motor 26 is greater than the torque force of the first torsion spring 47.

[0058] The first torsion spring 47 is sleeved on the rotating shaft 44, with one end fixed to the inner wall of the transmission groove 45 and the other end connected to the transmission plate 46. It continuously applies an outward swinging preload torque to the first plate. When the first drive motor 26 drives the first plate to swing inward through the transmission system (i.e., close the guide opening 2), because the motor's torque is greater than the spring torque of the first torsion spring 47, the first plate continuously swings its angle, ensuring a gradual pressure loading between the sealing surface of the first plate and the guide opening 2 during the closing process. When the first plate closes to the working position, the torque of the first drive motor 26 and the torque of the first torsion spring 47 form a stable balance. The corresponding drive plate can cooperate with the guide opening 2 to perform dielectric property testing on the powder inside the resonant cavity.

[0059] Furthermore, the flipping of the third drive plate 23 is oscillated by the second swing drive mechanism 5. The second swing drive mechanism 5 includes a rotating wheel 51 mounted on the outer wall of the housing 1. The rotating wheel 51 is wound with a drive line 52. The outer end of the drive line 52 is connected to the back of the third drive plate 23. The rotating wheel 51 can rotate to wind or unwind the drive line 52 to drive the third drive plate 23 to swing outward. The transmission shaft connected to the third drive plate 23 is fitted with a second torsion spring. The torsion direction of the second torsion spring is opposite to the torsion direction of the first torsion spring 47. The second torsion spring can drive the rotating shaft 44 to rotate and drive the third drive plate 23 to swing inward.

[0060] In this embodiment, the drive wire 52 of the second drive module is made of high-strength aramid fiber braided yarn and wound around the rotating wheel 51; the flexibility of the drive wire 52 can adapt to the complex curved surface of the outer wall of the housing 1. The second torsion spring is opposite in direction to the first torsion spring 47 and always applies an inward swinging preload torque to the third drive plate 23. When the drive wire 52 pulls the third drive plate 23 to swing outward, it overcomes the spring torque. When the rotating wheel 51 unwinds, the spring torque of the second torsion spring dominates the inward swing of the third drive plate 23, and the preload of the second torsion spring ensures that the third drive plate 23 always stays close to the guide opening 2 during the closing process.

[0061] Furthermore, a fixed bracket 53 is installed on the outer wall of the housing 1. The fixed bracket 53 is equipped with a variable frequency crane motor 54 and a motor shaft. The drive end of the variable frequency crane motor 54 is coaxially connected to the motor shaft, and the motor shaft is connected to the rotating wheel 51. A first guide wheel 55 for guiding the drive line 52 is also installed on the outer wall of the housing 1. A second guide wheel 56 for guiding the drive line 52 is installed on the back of the third drive plate 23. The first guide wheel 55 can move laterally, and the second guide wheel 56 can move laterally in a direction perpendicular to the third drive plate 23.

[0062] The first guide wheel 55 achieves lateral extension and retraction via a micro linear module. Its position is controlled in real-time by the swing angle of the third drive plate 23. When the third drive plate 23 swings from 0° to 90°, the horizontal angle between the drive line 52 and the rotating wheel 51 increases from 0° to 30°, and the first guide wheel 55 synchronously extends and retracts outward, ensuring that the drive line 52 always remains aligned with the tangential direction of the groove of the rotating wheel 51. The second guide wheel 56 adaptively extends and retracts in a direction perpendicular to the drive plate via a spring-return telescopic structure. When the third drive plate 23 swings, its vertical distance from the first guide wheel 55 changes, and the second guide wheel 56 automatically compensates for the height difference through extension and retraction, stabilizing the wrap angle of the drive line 52 on the surface of the third drive plate 23. The stability of the wrap angle ensures that the pulling force of the drive line 52 on the third drive plate 23 is always perpendicular to the plate body, avoiding deformation of the drive plate caused by the lateral component of the pulling force and ensuring the sealing surface's fitting accuracy.

[0063] In addition, the motor shaft integrates a magneto-electric encoder to provide real-time feedback on the angle of the rotating wheel 51. Through a PID algorithm and the swing angle of the third drive board 23, which is monitored by a laser displacement sensor, a closed-loop control is formed. When the drive line 52 experiences a sudden increase in tension due to jamming, the machine immediately stops and reverses to release the tension, thus preventing the drive line 52 from breaking.

[0064] In addition, when the first drive board 21, the second drive board 22 and the third drive board 23 switch alternately, the control signal of the variable frequency motor and the signal of the first drive motor 26 are synchronized through the same PLC to ensure that the swinging motion of different drive boards does not interfere with each other.

[0065] Furthermore, an inclined auxiliary telescopic cylinder 57 is also provided on the outer wall of the housing 1, and a transversely arranged drive linear module 58 is provided on the outer wall of the housing 1. A transverse moving seat 59 is installed on the drive end of the drive linear module 58, and the auxiliary telescopic cylinder 57 is installed on the transverse moving seat 59. The drive end of the auxiliary telescopic cylinder 57 faces the bottom of the housing 1, and a guide pressure block 60 is installed on the edge of the third drive plate 23, which contacts the drive end of the auxiliary telescopic cylinder 57. The driving force of the drive linear module 58 in conjunction with the auxiliary telescopic cylinder 57 is greater than the preload of the second torsion spring.

[0066] The auxiliary telescopic cylinder 57 and the second swing drive mechanism 5 are linked by PLC timing control. When the third drive plate 23 needs to be flipped outward, the piston rod of the auxiliary telescopic cylinder 57 extends, so that the third drive plate 23 can be flipped outward. At the same time, the rotating wheel 51 rotates and winds up the drive line 52. Under the dual force, the third drive plate 23 continuously flips outward, while the driving linear module 58 drives the auxiliary telescopic cylinder 57 to move, so that the guide block 60 at the end of the piston rod always presses against the third drive plate 23.

[0067] The first drive board 21 is equipped with a humidity sensor; the second drive board 22 is equipped with an ambient temperature sensor; and the third drive board 23 is equipped with a displacement sensor. The humidity sensor, ambient temperature sensor, and displacement sensor are all removable and replaceable. The first drive board 21, second drive board 22, and third drive board 23 each have three pre-drilled universal mounting holes with a hole spacing of 10mm. All sensors are uniformly designed with an outer diameter ≤3mm and a length ≤10mm, allowing any sensor to be inserted into any mounting hole. The testing software has a built-in sensor model database, including pressure, temperature, humidity, and vibration sensors. After sensor replacement, the model is automatically identified via Bluetooth, eliminating the need for manual parameter modification and directly matching the corresponding data processing algorithm.

[0068] Hygroscopic powders, upon absorbing moisture, experience a significant increase in εr and tanδ, necessitating a humidity sensor for early warning and detection. High-temperature sensitive powders experience dielectric parameter drift due to temperature increases, requiring an ambient temperature sensor for compensation. Powders prone to agglomeration exhibit distorted field distribution due to uneven packing, requiring pressure and displacement sensors to monitor density and morphology. Therefore, this solution can separately test the dielectric properties of commonly used hygroscopic powders, high-temperature sensitive powders, and powders prone to agglomeration, ensuring test diversity. For testing less commonly used powders, one or more sensors can be replaced to further diversify detection methods.

[0069] In summary, the present invention possesses the excellent characteristics described above, which enhances its effectiveness in use compared to previous technologies, making it a highly practical product.

[0070] The above description is only a preferred embodiment of the present invention. For those skilled in the art, there will be changes in the specific implementation and application scope based on the ideas of the present invention. The content of this specification should not be construed as a limitation of the present invention.

Claims

1. A cylindrical resonant cavity for separating the dielectric properties of powder materials based on a quasi-optical cavity, comprising a housing, wherein an upper cavity, a sample chamber, and a lower cavity are disposed within the housing, characterized in that: The upper cavity has a cylindrical structure and is made of oxygen-free copper. The inner wall of the upper cavity has a polished surface with a surface roughness Ra≤0.1μm. The polished surface is electroplated with a 50nm thick nanodiamond coating. The bottom of the upper cavity is connected to the sample chamber. The sample chamber includes a cylindrical hollow cavity. The sample chamber is made of flexible polytetrafluoroethylene, and the inner wall of the cavity is coated with a hydrophobic nano-coating with a thickness of 10 μm. An elastic pressure ring is installed at the top of the middle cavity and a pressure sensor is installed at the bottom; magnetic attraction points are installed at the top and bottom of the sample chamber respectively, the top of the sample chamber is magnetically connected to the upper cavity, and the bottom of the sample chamber is magnetically connected to the lower cavity. The lower cavity is a cylindrical structure with a heat insulation sleeve on its surface and a wave-absorbing material layer attached to the inner wall of the lower cavity.

2. The cylindrical resonant cavity based on a quasi-optical cavity and featuring discrete dielectric properties of powder materials, as described in claim 1, is characterized in that: The bottom of the housing is provided with a guide opening, and a first drive plate, a second drive plate and a third drive plate are hinged to the guide opening. The first drive plate, the second drive plate and the third drive plate are respectively surrounding the periphery of the housing. The first drive plate, the second drive plate and the third drive plate can swing to block the guide opening. The first drive plate is equipped with a first sensing device, the second drive plate is equipped with a second sensing device and the third drive plate is equipped with a third sensing device. The first drive plate and the second drive plate include a first plate body. The two first plate bodies are arranged opposite each other. The housing is provided with a first swing drive mechanism that drives the first plate bodies of the first drive plate and the second drive plate to swing longitudinally, and a second swing drive mechanism that drives the third drive plate to swing longitudinally.

3. The cylindrical resonant cavity based on a quasi-optical cavity and with separated dielectric properties of powder materials according to claim 2, characterized in that: The first swing drive mechanism includes two spaced-apart first drive modules. Each first drive module includes a longitudinal rack arranged longitudinally on the housing. A rotatable first drive gear is installed on the side wall of the housing. The first drive gear meshes with the longitudinal rack for transmission. The first drive gear is mounted on a synchronously rotating first drive shaft. A second drive bevel gear is installed at the outer end of the first drive shaft. A third drive bevel gear that meshes with the second drive bevel gear is also installed on the side wall of the housing. A first synchronous pulley is coaxially mounted on the third drive bevel gear. A hinge structure is installed at the bottom of the housing. The hinge structure rotatably connects the first plate to the housing. A second synchronous pulley that cooperates with the first synchronous pulley is installed at the outer end of the hinge structure. A synchronous belt drives between the second synchronous pulley and the first synchronous pulley.

4. The cylindrical resonant cavity based on a quasi-optical cavity and with separated dielectric properties of powder materials according to claim 3, characterized in that: The housing contains a first drive motor and a lead screw drive mechanism that is connected to the drive end of the first drive motor. The drive end of the lead screw drive mechanism is equipped with a transmission sleeve, which is connected to a longitudinal rack. The housing is formed with a longitudinally arranged transmission groove. A compression spring for buffering movement of the longitudinal rack is installed at the top of the transmission groove. The bottom of the compression spring is connected to the longitudinal rack. Laterally protruding sliding blocks are formed on both long sides of the longitudinal rack. A guide groove is formed along the length of the inner wall of the transmission groove. Guide balls that roll in cooperation with the guide groove are installed on the sliding blocks.

5. A cylindrical resonant cavity based on a quasi-optical cavity and featuring discrete dielectric properties of powder materials, as described in claim 3, characterized in that: The hinge structure includes three transmission grooves formed on the long sides of the bottom of the housing. A rotating shaft is installed in the transmission groove. One of the inner long sides of the first drive plate, the second drive plate, and the third drive plate is formed with a transmission plate embedded in the transmission groove. The transmission plate is fixedly connected to the rotating shaft. A part of the rotating shaft connected to the first plate is exposed outward. A second synchronous pulley is installed on the exposed part of the transmission shaft. A first torsion spring is provided in the transmission groove and sleeved on the transmission shaft. The torque force of the first drive motor is greater than the torque force of the first torsion spring. The elastic force of the first torsion spring can drive the rotating shaft to rotate and drive the first plate to swing outward.

6. The cylindrical resonant cavity based on a quasi-optical cavity and featuring discrete dielectric properties of powder materials, as described in claim 5, is characterized in that: The second swing drive mechanism includes two rotating wheels mounted on the outer wall of the housing. The rotating wheels are wound with drive lines, and the outer ends of the drive lines are connected to the back of the third drive plate. The rotating wheels can rotate to wind or unwind the drive lines to drive the third drive plate to swing outward. A second torsion spring is sleeved on the rotating shaft connected to the third drive plate. The torsion direction of the second torsion spring is opposite to that of the first torsion spring. The second torsion spring can drive the rotating shaft to rotate and drive the third drive plate to swing inward.

7. A cylindrical resonant cavity based on a quasi-optical cavity and featuring separated dielectric properties of powder materials, as described in claim 6, characterized in that: A fixed bracket is installed on the outer wall of the housing. The fixed bracket is equipped with a variable frequency crane motor and a motor shaft. The drive end of the variable frequency crane motor is coaxially connected to the motor shaft, and the motor shaft is connected to a rotating wheel. A first guide wheel for guiding the drive line is also installed on the outer wall of the housing. A second guide wheel for guiding the drive line is installed on the back of the third drive plate. The first guide wheel can move laterally, and the second guide wheel can move in a direction perpendicular to the third drive plate.

8. A cylindrical resonant cavity based on a quasi-optical cavity and featuring discrete dielectric properties of powder materials, as described in claim 7, characterized in that: The outer wall of the box is also provided with an inclined auxiliary telescopic cylinder, and the outer wall of the box is provided with a horizontally arranged drive linear module. The drive end of the drive linear module is equipped with a horizontal moving seat, the auxiliary telescopic cylinder is installed on the horizontal moving seat, the drive end of the auxiliary telescopic cylinder faces the bottom of the box, and the edge of the third drive plate is equipped with a guide pressure block that contacts the drive end of the auxiliary telescopic cylinder.

9. A cylindrical resonant cavity based on a quasi-optical cavity and featuring discrete dielectric properties of powder materials, as described in claim 7, characterized in that: The first drive board is equipped with a humidity sensor; the second drive board is equipped with an ambient temperature sensor; and the third drive board is equipped with a displacement sensor. The humidity sensor, ambient temperature sensor, and displacement sensor can be removed and replaced.

10. A cylindrical resonant cavity based on a quasi-optical cavity and featuring discrete dielectric properties of powder materials, as described in claim 1, characterized in that: The outer wall of the box is formed with a side window, which is horizontally aligned with the sample chamber. The side window is hinged to a side door that can swing longitudinally. The side door is provided with a support rail along its length. The outer end of the sample chamber is equipped with a support sliding seat that slides with the support rail. A side top block is installed on the back of the side door.

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