An assembled resonator and a processing technology thereof

Abstract

The present application relates to the technical field of gyroscopes, and specifically relates to an assembled resonator and a processing technology thereof, comprising a hemispherical shell part and a center column part, a through connecting hole is formed at the top of the hemispherical shell part, the center column part is arranged in the connecting hole, and the hemispherical shell part and the center column part are detachably connected through a matching structure selected from any one of the following: an interference fit structure, the connecting hole is a cylindrical hole, the outer wall of the center column part is a cylindrical surface, a taper surface matching structure, the connecting hole is an inner circular taper hole with a large upper part and a small lower part, the outer wall of the center column part is an outer circular taper surface, a radial locking is formed by axial compression, and coaxiality deviation is compensated by self-centering; a threaded connection structure, the inner wall of the connecting hole and the outer periphery of the center column part are respectively processed with micro inner and outer threads directly formed on the quartz glass material body, and the fixing is realized through the engagement of the threaded pair, the present application replaces chemical bonding with mechanical connection, eliminates the influence of glue stress on the quality factor, and realizes detachable maintenance and self-reference assembly.

Description

Technical Field

[0001] This invention relates to the field of gyroscope technology, specifically to an assembled resonator and its fabrication process. Background Technology

[0002] The hemispherical resonator is the core sensing element of a hemispherical resonant gyroscope, and its manufacturing precision directly affects the gyroscope's key performance indicators such as quality factor and frequency splitting. The traditional manufacturing methods for hemispherical resonators mainly involve the following technical approaches and problems: Integrated machining approach: The hemispherical shell and central column are machined from a single piece of fused silica. The advantage of this approach is the absence of connecting interfaces, theoretically eliminating assembly stress. However, its disadvantages include extremely difficult machining of the inner surface of the hemispherical shell, requiring specialized and complex tooling and ultra-precision machining equipment, resulting in significant material waste, low yield, and high manufacturing costs.

[0003] Split-type bonding route: In order to solve the problem of integrated processing, the existing technology has developed a scheme to prepare the hemispherical shell and the central column separately and then fix them by bonding solution. For example, patent document CN118518086B discloses a technical solution to heat press the hemispherical shell and the central column into one piece, and then bond the two together by bonding solution. Although this scheme reduces the processing difficulty of individual parts, it introduces new problems: (1) shrinkage stress is generated during the curing process of the bonding solution and thermal stress is introduced during the welding process. These residual stresses act on the working area of ​​the resonator, resulting in a significant reduction in the quality factor; (2) chemical bonding is an irreversible connection. If the coaxiality is found to be unqualified after assembly or a single part is damaged during use, it cannot be disassembled and repaired, and the whole part can only be scrapped; (3) during assembly, it is necessary to rely on external molding molds and laser detection components for positioning and alignment. The system is complex, the reference is converted multiple times, the cumulative error is large, and the reliability is limited.

[0004] Therefore, how to provide a resonator structure and process that can retain the manufacturing convenience of split processing, eliminate the influence of chemical bonding stress on the quality factor, enable disassembly and maintenance, and simplify the assembly and positioning system has become a technical problem that urgently needs to be solved in this field. Summary of the Invention

[0005] This invention is achieved through the following technical solution: This invention provides an assembled resonator, in which a through-hole is formed at the top of the hemispherical shell portion. The outer periphery of the opening of this through-hole forms a positioning plane, which is perpendicular to the axis of the through-hole, constituting an axial assembly reference plane. A central column portion passes through the through-hole and is detachably connected to the hemispherical shell portion through a mating structure selected from any of the following.

[0006] The aforementioned positioning plane design directly integrates the assembly datum into the hemispherical shell itself, forming a self-datum assembly system. Its technical advantage lies in the fact that when the central column is inserted into the connecting hole for assembly, this positioning plane provides a clear and unique axial positioning reference, eliminating the need for external molds or complex optical alignment devices. Since the positioning plane and the connecting hole can be formed in the same mounting process, they possess extremely high perpendicularity accuracy, thus ensuring the coaxiality of the central column and the hemispherical shell during assembly.

[0007] This invention provides three optional mechanical connection structures, all of which use purely mechanical methods for bonding without introducing any chemical bonding solutions or welding materials. This fundamentally eliminates the damage to the quality factor caused by the curing shrinkage stress of the adhesive layer in chemical bonding schemes, as well as the long-term reliability issues caused by adhesive layer aging. Furthermore, the mechanical connection inherently possesses disassembly capability; if a component is found to be substandard in precision during the assembly and inspection phase, it can be disassembled, replaced, and reassembled, significantly reducing manufacturing costs.

[0008] The first type is an interference fit structure. The connecting hole is a cylindrical hole, and the corresponding position of the central column is a cylindrical surface with a slightly larger outer diameter. The interference is limited to the micrometer range of 0.001mm to 0.005mm. This parameter range is specifically designed for brittle materials such as quartz glass. Too small an interference cannot provide sufficient connecting force, while too large an interference will cause the material to crack during assembly. This solution uses a micro-interference combined with a special cryogenic assembly process to generate uniform radial positive pressure between the mating surfaces, achieving physical locking without any chemical adhesives while ensuring that the assembly process does not damage the quartz material.

[0009] The second type is a conical mating structure. The connecting hole is an inner conical hole that is larger at the top and smaller at the bottom, and the corresponding position of the central column has a matching outer conical surface, with the taper controlled between 1:10 and 1:20. This specific taper range has a dual technical effect: firstly, during axial clamping, the wedge effect proportionally amplifies the axial force into a radial locking force, allowing a small axial force to generate sufficient connection strength; secondly, this taper has a self-centering characteristic. During the pressing process, even if there is a slight initial misalignment, the wedge action between the inner and outer conical surfaces will generate a centering restoring torque, automatically guiding the central column to be coaxial with the connecting hole, thereby actively compensating for coaxiality deviations during assembly.

[0010] The third type is a threaded connection structure. Internal and external threads are machined on the inner wall of the connecting hole and the outer circumference of the central column, respectively, and the two threads engage to form a mechanical mesh. Unlike using separate metal threaded inserts, the internal and external threads in this design are micro-threads directly machined into the quartz glass material itself. This machining method avoids thermal stress problems caused by the mismatch in the thermal expansion coefficients of dissimilar materials, ensuring the consistency of the overall material of the resonator and contributing to maintaining a high quality factor.

[0011] Furthermore, the aforementioned connecting hole is located in the central region of the top of the hemispherical shell, precisely within the intersection area of ​​the vibration nodal lines of the hemispherical resonator's operating modes. The technical advantage of this placement is that the hemispherical resonator vibrates in specific second or third-order resonance modes during operation, exhibiting a distinct regional distribution—the amplitude is largest in the equatorial lip region, while the amplitude is extremely low in the central region at the intersection of all vibration nodal lines. Placing the connecting hole and its mating structure in this low-amplitude region means that the material region affected by the localized stress field generated during assembly hardly participates in the vibration during resonance. Therefore, the contribution of this localized stress field to the dissipation of resonant energy is minimal, and its influence on the quality factor is naturally suppressed. In other words, it is not that the stress field is "isolated," but rather that it is precisely placed in a location insensitive to it.

[0012] The hemispherical shell and central column can be made of quartz glass or metal. When quartz glass is used, its outer surface has a surface metallization layer. The function of the surface metallization layer is that, since quartz glass itself is an insulator, a conductive thin film needs to be formed on its surface to form a capacitor structure with the external plate electrodes of the resonator, thereby realizing electrostatic drive and capacitive detection of vibration signals. In this solution, the surface metallization treatment is performed after all machining and assembly steps are completed, which can effectively protect the metallization film from mechanical damage caused by the aforementioned processes.

[0013] The present invention also provides a processing technology for the above-mentioned assembled resonator, which includes six core steps, forming a complete technical route of separate manufacturing, pre-annealing, mechanical integration, and post-processing compensation.

[0014] Step S1: Independently machine the hemispherical shell. Using the top end face of the hemispherical shell directly as the positioning plane and as the mounting datum, machine the connecting hole in the same mounting process, ensuring that the axis of the connecting hole is perpendicular to the positioning plane. The originality of this step lies in combining the machining of the datum surface required for subsequent assembly with the machining of the connecting hole under the same positioning datum. The machine tool's single-setup accuracy naturally ensures the perpendicularity relationship between the datum surface and the hole axis, eliminating the need for subsequent grinding or calibration.

[0015] Step S2: Independently process the central column. Machining the hemispherical shell and the central column separately significantly reduces the difficulty of complex machining of the inner surface of the hemispherical shell in traditional one-piece molding processes, enabling both components to be mass-produced with precision.

[0016] Step S3: Annealing. Vacuum annealing is performed on the finished hemispherical shell and central column separately. The unique aspect of this step lies in the timing and purpose of the annealing: it is precisely scheduled after the separate machining is completed and before mechanical assembly. The core purpose is to establish a low-stress baseline for subsequent mechanical connections. Because the two components are annealed independently, their respective residual machining stresses are completely eliminated, and the material returns to a low-stress state close to theoretical values. This makes the stresses introduced by subsequent assembly (interference stress, conical locking force, or thread preload) the only source of stress acting on the resonator, thus achieving precise prediction and control of assembly stress. Specifically, the vacuum annealing process includes: placing the hemispherical shell and central column separately in a vacuum environment, heating them at a controlled rate to the annealing temperature range of quartz glass, holding them at that temperature for a preset time, and then slowly cooling them to room temperature at a controlled rate. This heating, holding, and slow cooling process eliminates the residual stresses introduced during machining, allowing the material to return to a low-stress baseline state before assembly.

[0017] Step S4: Assembly. Using the axial assembly reference surface formed in step S1 as the sole reference, insert the central column into the connecting hole and assemble it through any one of the following methods: interference fit, tapered fit, or threaded connection, to obtain the assembled resonator blank.

[0018] Step S5: Finishing. The assembled resonator blank undergoes overall micro-machining and dynamic balancing. This is a post-processing compensation step in this solution. Its function is to correct even minor errors during assembly through subsequent overall finishing and balancing, thereby relaxing the stringent precision requirements of the assembly process and improving the practicality and yield of the process. Overall micro-machining includes micro-machining of the inner and / or outer spherical surfaces of the assembled hemispherical shell to correct the coaxiality deviation between the hemispherical shell's center of symmetry and the central column axis caused by assembly, ensuring that the coaxiality error between the final resonator's center of symmetry and the central column axis does not exceed 0.005mm. Dynamic balancing includes localized material removal on the resonator blank for quality adjustment to suppress frequency fragmentation caused by assembly stress or geometric asymmetry, reducing it to below a preset threshold.

[0019] Step S6: Surface treatment. Perform surface metallization treatment on the finished resonator.

[0020] When using an interference fit for assembly, this invention employs a three-step method of freezing, pushing in, and restoring, specifically designed to overcome the technical obstacle of easily cracking or scratching quartz glass during room-temperature interference fitting. First, the central column is cryogenically frozen, causing its outer diameter to shrink to less than the diameter of the connecting hole due to thermal contraction. The freezing temperature is precisely calculated based on the interference amount and the thermal expansion coefficient of the quartz glass, ensuring that the radial clearance after shrinkage is positive and does not exceed 5 micrometers. At this point, the central column and the connecting hole have a clearance fit, allowing for unobstructed axial pushing in. During pushing in, the corresponding end face of the central column abuts against and fits against the positioning plane as the axial positioning reference. After restoring to room temperature, the central column's thermal expansion returns to its original size, forming a micro-interference of 0.001mm to 0.005mm between the mating surfaces. Because the locking force is gradually built up through the elastic deformation of the material itself after restoring to room temperature, rather than being generated instantaneously through forced pressing, the entire assembly process causes no impact or scratch damage to the brittle quartz material, achieving damage-free locking.

[0021] When using a conical fit for assembly, the connecting hole is an inner conical hole that is larger at the top and smaller at the bottom. The outer wall of the central column has an outer conical surface machined at the corresponding position to match its taper, with a taper of 1:10 to 1:20. During assembly, the outer conical surface of the central column is first inserted into the inner conical hole of the connecting hole, and then a controlled axial clamping force is applied to the central column. During the pressing process, the relationship curve between the pressing force and displacement is monitored in real time to determine whether the contact state of the conical surfaces is normal. When there is a slight initial misalignment, the wedge action between the inner and outer conical surfaces will automatically generate a centering restoring torque, guiding the central column to be coaxial with the connecting hole, overcoming the risk of misalignment and seizing. The clamping force is continued until the corresponding end face of the central column abuts against the positioning plane, and then the force is immediately stopped. The end face contact acts as a mechanical stop, preventing excessive force from causing the conical surface to crack due to excessive stress. After locking, the specific taper of 1:10 to 1:20 satisfies the self-locking condition of the quartz-quartz friction pair. After the external axial clamping force is removed, the conical surfaces can still maintain the locked state by friction and will not loosen.

[0022] When using a threaded connection for assembly, the inner wall of the connecting hole is machined with internal threads, and the outer circumference of the central post is machined with external threads at corresponding positions. Both internal and external threads are micro-threads directly machined into the quartz glass material. During assembly, a reverse threading operation is first performed: align the external thread end of the central post with the internal thread inlet of the connecting hole, and slowly rotate in the opposite direction without actively applying axial clamping force. When the end faces of the thread inlets cross each other, generating an axial runout signal, it is confirmed that the initial threads of the internal and external threads are accurately aligned. This operation avoids thread breakage caused by forced screwing due to thread misalignment. After successful threading, screw in the thread in the forward direction, keeping the axis of the central post parallel to the axis of the connecting hole throughout the screwing process, and using a special engagement tool with a preset torque limit for engagement. The preset torque limit is determined as follows: The maximum shear stress that the micro-thread can withstand during engagement is calculated based on the allowable shear strength of the quartz material. This maximum shear stress is then converted into an allowable engagement torque value, which is used as the preset torque limit for the engagement tool. When the engagement torque reaches this preset limit, the engagement tool automatically stops applying torque, fundamentally eliminating the risk of breaking the central post due to excessive torque and preventing shear fracture at the thread root. Finally, the thread is screwed in until the corresponding end face of the central post abuts against the positioning plane. This end face contact serves as a mechanical stop signal for complete engagement, ensuring consistent engagement depth and preventing over-tightening.

[0023] Compared with the prior art, the present invention has the following advantages and beneficial effects: (1) By replacing traditional chemical bonding with interference fit, tapered fit or threaded connection, the influence of adhesive stress on the quality factor of the resonator is fundamentally eliminated, and the resonator is given the ability to be disassembled and repaired, thus overcoming the technical problem that quartz glass is delicate and fragile and difficult to use interference fit in this field.

[0024] (2) By setting a positioning plane at the top of the hemispherical shell that is formed in the same process as the connecting hole, self-datum assembly is realized, eliminating the dependence on complex external forming molds and laser alignment systems in the existing technology, simplifying the assembly system and shortening the precision transfer chain.

[0025] (3) By placing the annealing process before the assembly and after the separate processing, a low stress background is established for the mechanical connection, making the assembly stress the only controllable variable, and forming a close process synergy with the separate manufacturing and mechanical connection.

[0026] (4) By performing micro-cutting finishing and dynamic balancing post-processing compensation after assembly, residual errors that may be introduced in the assembly process are corrected, the precision requirements of the assembly process are relaxed, and the practicality and yield of the overall process are improved.

[0027] (5) Targeted process solutions were developed for the cold shrinkage assembly of interference fit, the pressure and displacement monitoring stop of tapered fit, and the reverse toothing and preset torque control of threaded connection, which systematically overcame the specific process obstacles faced by brittle quartz materials in the three mechanical connection methods. Attached Figure Description

[0028] The accompanying drawings, which are included to provide a further understanding of embodiments of the invention and form part of this application, do not constitute a limitation thereof. In the drawings: Figure 1 This is a schematic diagram of the assembled resonator structure of the present invention; Figure 2 This is a schematic diagram of the interference fit connection of the present invention; Figure 3 This is a schematic diagram of the conical surface mating connection of the present invention; Figure 4 This is a schematic diagram of the threaded connection of the present invention; Figure 5 This is an overall flow chart of the processing technology of the present invention; Figure 6 This is a detailed flowchart of step S4 under the interference fit method of the present invention; Figure 7 This is a detailed flowchart of step S4 in the conical surface mating method of the present invention; Figure 8 This is a detailed flowchart of step S4 in the threaded connection method of the present invention; The attached diagram shows the markings and corresponding component names: 1. Hemispherical shell; 10. Connecting hole; 100. Cylindrical hole; 101. Inner conical hole; 102. Internal thread; 2. Central column; 20. Cylindrical surface; 21. Outer conical surface; 22. External thread. Detailed Implementation

[0029] To make the objectives, technical solutions, and advantages of this invention clearer, the invention will be further described in detail below with reference to embodiments and accompanying drawings. The illustrative embodiments and descriptions of this invention are for illustrative purposes only and are not intended to limit the invention. It should be noted that this invention is already in the actual research and development stage.

[0030] Example 1 like Figure 1 , Figure 2 , Figure 5 , Figure 6This embodiment provides an assembled resonator, including a hemispherical shell portion 1 and a central column portion 2. A through-hole 10 is formed at the top of the hemispherical shell portion 1. The outer periphery of the opening of the through-hole 10 forms a positioning plane, which is perpendicular to the axis of the through-hole 10, constituting an axial assembly reference plane. The central column portion 2 passes through the through-hole 10.

[0031] The connecting hole 10 is located in the central region at the top of the hemispherical shell 1. This central region is situated within the intersection area of ​​the vibration nodal lines of the working mode of the hemispherical resonator, where the amplitude is extremely low. This location choice confines the local stress field generated by the connecting hole 10 and its mating structure to a low-amplitude region, effectively suppressing its influence on the resonance quality factor.

[0032] The hemispherical shell 1 and the central pillar 2 are made of quartz glass. The outer surfaces of the hemispherical shell 1 and the central pillar 2 have a surface metallization layer, which is formed after all machining and assembly steps are completed. This metallization layer is used to form a capacitor structure with the external plate electrode to realize electrostatic drive and capacitive detection of vibration signals.

[0033] In this embodiment, the hemispherical shell 1 and the central column 2 are fixedly connected by an interference fit structure. The connecting hole 10 is a cylindrical hole 100, and the outer wall of the central column 2 is a cylindrical surface 20 at the corresponding position. The outer diameter of the cylindrical surface 20 is larger than the diameter of the cylindrical hole 100, and the interference is 0.003 mm.

[0034] The fabrication process of the above-mentioned assembled resonator is as follows: Step 1: Machining the hemispherical shell 1 independently. Using the top end face of the hemispherical shell 1 as the positioning plane and as the mounting reference, the connecting hole 10 is machined in the same mounting process, so that the axis of the connecting hole 10 is perpendicular to the positioning plane, thereby forming an axial assembly reference surface.

[0035] Step 2, independently machine the center column 2. Machin the center column 2 according to the design dimensions, and machine the outer diameter of the corresponding position to be 0.003mm larger than the diameter of the connecting hole 10.

[0036] Step 3, Annealing. The processed hemispherical shell 1 and central column 2 are placed in a vacuum annealing furnace and heated at a controlled rate to the annealing temperature range of quartz glass. After holding at this temperature for a preset time, they are slowly cooled to room temperature at a controlled rate. The above heating, holding, and slow cooling process eliminates the residual stress introduced during processing, allowing the material to return to its low-stress background state before assembly.

[0037] Step four, assembly. This embodiment uses an interference fit for assembly. First, the central column 2 is placed in a low-temperature environment for freezing treatment. The freezing temperature is calculated based on the interference amount of 0.003 mm and the thermal expansion coefficient of quartz glass, ensuring that the outer diameter of the central column 2 shrinks to a size smaller than the diameter of the connecting hole 10, and the radial clearance after shrinkage is positive and does not exceed 5 μm. Then, the frozen and shrunken central column 2 is pushed axially into the connecting hole 10 with a clearance fit until the corresponding end face of the central column 2 abuts and fits against the positioning plane. Finally, it is restored to room temperature, and the central column 2 thermally expands back to its original size, forming an interference fit of 0.003 mm between the inner wall of the connecting hole 10 and the outer wall of the central column 2. Uniform radial positive pressure is generated through the elastic deformation of the material, achieving damage-free locking.

[0038] Step 5, Finishing. The assembled resonator blank undergoes overall micro-machining and dynamic balancing. Overall micro-machining involves minor cutting of the inner and outer spherical surfaces of the hemispherical shell 1, directly correcting the coaxiality deviation between the center of symmetry of the hemispherical shell 1 and the axis of the central column 2 caused by assembly, ensuring the coaxiality error does not exceed 0.005mm. Dynamic balancing involves locally removing material from the resonator blank to adjust its quality, suppressing frequency fragmentation caused by assembly stress or geometric asymmetry, and reducing it to below a preset threshold.

[0039] Step 6, Surface Treatment. The assembled hemispherical resonator, after finishing, undergoes surface metallization treatment to form a conductive functional layer.

[0040] Example 2

[0041] like Figure 1 , Figure 3 , Figure 5 , Figure 7 As shown, the structural difference between this embodiment and Embodiment 1 is that the hemispherical shell 1 and the central column 2 are fixedly connected by a conical surface mating structure. The connecting hole 10 is an inner conical hole 101 that is larger at the top and smaller at the bottom, meaning that the opening diameter of the connecting hole 10 is larger at the top outer end face of the hemispherical shell 1 and gradually decreases as it extends downward to the inner surface of the hemispherical shell 1. The outer wall of the central column 2 is machined with an outer conical surface 21 at a corresponding position that matches the taper of the inner conical hole 101. The larger end of the outer conical surface 21 is at the top and the smaller end is at the bottom, with a taper of 1:15. The outer conical surface 21 is wedged into the inner conical hole 101 from top to bottom, forming a radial lock through axial compression and compensating for coaxiality deviations by self-centering.

[0042] In this embodiment, the choice of taper 1:15 is not arbitrary, but is derived based on the following mechanical principles and material properties.

[0043] First, the conical fit must maintain a locked state solely by friction after the axial clamping force is removed, without loosening. This requirement corresponds to the frictional self-locking condition, meaning the semi-cone angle α of the conical surface must be less than the static friction angle φ of the mating surface materials. The relationship between the static friction angle φ and the static friction coefficient μ is as follows: φ = arctan(μ) For a friction pair composed of quartz glass and quartz glass, the static friction coefficient μ is typically between 0.15 and 0.25. Taking a conservative value of μ = 0.15, the corresponding friction angle is: φ = arctan(0.15) ≈ 8.5° The relationship between taper C and half-cone angle α is: C = 2×tan(α) When the taper C = 1:15, the half-cone angle is: α= arctan(C / 2) = arctan(1 / 30) ≈ 1.91° This angle is significantly smaller than the friction angle of quartz glass (8.5°), satisfying the self-locking condition of α < φ, while retaining sufficient safety margin. Extending this, the half-cone angle corresponding to a taper range of 1:10 is approximately 2.86°, and the half-cone angle corresponding to a taper range of 1:20 is approximately 1.43°, both far smaller than the minimum friction angle of quartz glass, thus reliably achieving self-locking.

[0044] Secondly, during the clamping process, a contact stress σ is generated between the mating surfaces of the conical surface. This stress must be much less than the allowable compressive strength σ_allow of the quartz glass; otherwise, the material will crack. One of the core functions of the taper is "deceleration and force amplification," that is, through the wedge effect, the relatively small axial force F_a is proportionally amplified into a normal force N perpendicular to the conical surface. This normal force is decomposed into a radial component to produce a locking effect, and on the other hand, it determines the contact stress of the conical surface, ensuring that σ < σ_allow and avoiding cracking. In this embodiment, the 1:15 taper smoothly converts the axial clamping force F_a into the normal force N, allowing the operator to indirectly control the amplitude of N by precisely controlling F_a, ensuring that σ < σ_allow and avoiding conical surface cracking caused by excessive radial force.

[0045] Furthermore, the self-centering capability of the conical mating surface relies on the centering restoring torque generated when the inner and outer conical surfaces come into contact. If the taper is too large, the restoring torque is insufficient to effectively overcome the initial misalignment; if the taper is too small, the axial dimension is too long, which is detrimental to structural compactness. A 1:15 taper strikes a balance between providing sufficient centering restoring torque and maintaining structural compactness. Taking the central column with a nominal diameter d = 3 mm as an example, the axial length of the conical mating section only needs to be a few millimeters to achieve a complete contact area, meeting the requirements of the miniaturized hemispherical harmonic oscillator structure.

[0046] Considering the constraints of the above four aspects—self-locking condition α<φ, anti-cracking requirement σ<σ_allow, self-centering capability, and structural compactness—a taper range of 1:10 to 1:20 is the preferred range of the present invention. In this embodiment, 1:15 is specifically selected as the optimal implementation value.

[0047] In the processing technology of this embodiment, steps one to three and steps five to six are the same as in embodiment one. Step four is as follows: With the small end of the outer conical surface 21 of the central column 2 facing downwards, align it with the upper large opening of the connecting hole 10 from the outer side of the top of the hemispherical shell 1. Since the diameter d_small of the small end of the outer conical surface 21 is smaller than the diameter D_top of the upper opening of the connecting hole 10, the central column 2 can be easily initially inserted into the connecting hole 10 with a clearance fit, without the need for freezing. Subsequently, a controlled axial clamping force F_a is applied to the central column 2, causing it to move downwards axially. During the pressing process, the gap between the outer conical surface 21 and the inner conical hole 101 gradually decreases until the inner and outer conical surfaces begin to contact. At this time, the contact state of the conical surfaces is determined by monitoring the relationship curve between the pressing force F and the displacement s. When there is a slight initial misalignment, the wedge action between the inner and outer conical surfaces will automatically generate a centering restoring torque, guiding the central column 2 to be coaxial with the connecting hole 10, overcoming the possibility of conical surface seizing or one-sided contact caused by misalignment. The axial clamping force F_a continues to be applied, and the outer conical surface 21 continues to wedge downwards. The 1:15 taper amplifies F_a proportionally into a normal force N perpendicular to the conical surface. This normal force is further decomposed into a radial locking force component and an axial component, where the radial locking force component achieves uniform clamping of the hole wall. When the corresponding end face of the central column 2 abuts against the positioning plane at the top of the hemispherical shell 1, the force is immediately stopped, and the contact of this end face serves as a mechanical stop for assembly. At this time, a uniform radial lock is formed between the mating surfaces, and the taper satisfies the self-locking condition α < φ. After F_a is removed, the static friction force determined by the normal force N between the conical surfaces can still prevent the central column 2 from loosening upwards, ensuring that it will not loosen due to vibration or temperature changes during long-term use.

[0048] Example 3

[0049] like Figure 1 , Figure 4 , Figure 5, Figure 8 As shown, the structural difference between this embodiment and Embodiment 1 is that the hemispherical shell 1 and the central column 2 are fixedly connected by a threaded connection structure. The inner wall of the connecting hole 10 is machined with an internal thread 102, and the outer periphery of the central column 2 is machined with an external thread 22 at a corresponding position. The external thread 22 is screwed into the internal thread 102 to form a mechanical engagement. Both the internal thread 102 and the external thread 22 are micro-threads directly machined onto the quartz glass material body.

[0050] In the processing technology of this embodiment, steps one to three and steps five to six are the same as in embodiment one. Step four is as follows: Align the external thread 22 end of the central post 2 with the inlet of the internal thread 102 of the connecting hole 10. First, without actively applying axial clamping force, slowly rotate the central post 2 in the opposite direction until the end face of the thread inlet produces an axial runout signal, confirming that the external thread 22 and the internal thread 102 are successfully aligned, thus avoiding misalignment or thread breakage caused by forced screwing. Then, screw the central post 2 in the forward direction, keeping the axis of the central post 2 parallel to the axis of the connecting hole 10 during the screwing process, and use a screwing tool with a preset torque limit for screwing.

[0051] The preset torque limit is determined according to the following steps: The first step is to obtain the allowable shear strength τ_allow of the quartz glass material. This allowable shear strength can be found in a material handbook or obtained through standard mechanical testing. For example, the allowable shear strength τ_allow of a certain type of fused silica glass is 50 MPa.

[0052] The second step is to determine the effective shear cross-sectional area A of the micro-thread in the engaged state. When a micro-thread is subjected to engagement torque, failure typically occurs at the thread root, where the shear surface is the thread root shear surface based on the nominal thread diameter d. The effective shear cross-sectional area can be calculated using the following formula: A=π×d×L In the formula, d is the nominal diameter of the thread, and L is the thread engagement length. For example, when d = 3mm and L = 2mm, A = π × 3mm × 2mm ≈ 18.85mm².

[0053] The third step is to calculate the maximum shear force F_max that the micro-thread can withstand during engagement: F_max=τ_allow×A Following the above example, F_max = 50MPa × 18.85mm² = 942.5N.

[0054] The fourth step is to convert the maximum shear force F_max into the allowable engagement torque T_max. Based on the relationship between engagement torque and axial force in threaded drives, the following formula is used for the conversion: T_max=K×F_max×d In the formula, K is the tightening torque coefficient, and d is the nominal diameter of the thread. For a miniature threaded friction pair between quartz glass pieces, considering both the friction and contact state between the threads, the value of K ranges from 0.15 to 0.25. For example, if K = 0.2 and d = 3mm = 0.003m, then: T_max=0.2×942.5N×0.003m≈0.566N·m Fifth, use T_max as the preset torque limit for the engagement tool. The engagement tool should be a torque-controlled wrench or precision engagement device with torque setting and automatic release functions, and the preset torque limit should be set to T_max.

[0055] When the engagement torque reaches the preset limit, the engagement tool automatically stops applying torque to prevent excessive torque from causing the central post 2 to break and to prevent shearing fracture at the thread root.

[0056] Screw it in until the corresponding end face of the central column 2 abuts against the positioning plane. The contact of this end face serves as a stop signal for the screw to be in place, ensuring consistent screw depth and preventing over-screwing.

[0057] Example 4

[0058] The difference between this embodiment and embodiments one to three is that the hemispherical shell 1 and the central pillar 2 are made of metal. When metal is used, the surface metallization treatment in step six can be performed or not, depending on actual needs.

[0059] The specific embodiments described above further illustrate the purpose, technical solution, and beneficial effects of the present invention. It should be understood that the above description is only a specific embodiment of the present invention and is not intended to limit the scope of protection of the present invention. Any modifications, equivalent substitutions, improvements, etc., made within the spirit and principles of the present invention should be included within the scope of protection of the present invention.

Claims

1. An assembled resonator, comprising a hemispherical shell (1) and a central pillar (2), characterized in that: The top of the hemispherical shell (1) is provided with a through connecting hole (10). The outer periphery of the opening of the connecting hole (10) forms a positioning plane. The positioning plane is perpendicular to the axis of the connecting hole (10) and constitutes an axial assembly reference surface. The central column (2) passes through the connecting hole (10) and is detachably connected to the hemispherical shell (1) by any of the following fitting structures: The interference fit structure is as follows: the connecting hole (10) is a cylindrical hole (100), and the outer wall of the central column (2) is a cylindrical surface (20) at the corresponding position. The outer diameter of the cylindrical surface (20) is larger than the diameter of the cylindrical hole (100), and the interference is 0.001mm to 0.005mm. The conical mating structure has a connecting hole (10) that is larger at the top and smaller at the bottom. The outer wall of the central column (2) has an outer conical surface (21) that matches the taper of the inner conical hole (101) at the corresponding position. The taper is 1:10 to 1:

20. The outer conical surface (21) is wedged into the inner conical hole (101). Axial compression is used to form radial locking and self-centering is used to compensate for coaxiality deviation. The threaded connection structure has an internal thread (102) machined on the inner wall of the connecting hole (10), and an external thread (22) machined on the outer periphery of the central column (2) at the corresponding position. The external thread (22) is screwed into the internal thread (102) to form a mechanical engagement. Both the internal thread (102) and the external thread (22) are micro threads directly machined on the quartz glass material body.

2. The assembled resonator according to claim 1, characterized in that: The connecting hole (10) is opened in the central region at the top of the hemispherical shell (1), and the central region is located in the intersection area of ​​the vibration nodal lines of the working mode of the hemispherical harmonic oscillator.

3. The assembled resonator according to claim 1, characterized in that: The hemispherical shell (1) and the central column (2) are made of quartz glass or metal; When the material is quartz glass, the outer surfaces of the hemispherical shell (1) and the central column (2) have a surface metallization layer.

4. A fabrication process for the assembled resonator according to any one of claims 1-3, characterized in that, Includes the following steps: S1. Independently process the hemispherical shell part (1): Using the end face of the top of the hemispherical shell part (1) as the positioning plane and as the mounting reference, process the connecting hole (10) in the same mounting process, so that the axis of the connecting hole (10) is perpendicular to the positioning plane, thereby forming an axial assembly reference surface. S2, Independent machining center column (2); S3. Annealing treatment: Vacuum annealing treatment is performed on the hemispherical shell (1) and central column (2) after processing to eliminate residual stress and restore the material to a low stress background state. S4. Assembly: Using the axial assembly reference surface as a reference, insert the central column (2) into the connecting hole (10) and assemble it by any of the following fitting methods: interference fit, tapered fit or threaded connection, to obtain the assembled resonator blank. S5. Finishing: Perform overall micro-cutting finishing and dynamic balancing on the assembled resonator blank to compensate for assembly errors, and suppress frequency fragmentation to below the preset threshold through local adjustment. S6. Surface treatment: When the material of the hemispherical shell (1) and the central column (2) is quartz glass, the assembled hemispherical harmonic oscillator that has been finely processed is subjected to surface metallization treatment.

5. The processing technology according to claim 4, characterized in that, When the fit is an interference fit, step S4 specifically includes: The central column (2) is placed in a low-temperature environment for freezing treatment, so that its outer diameter shrinks to be smaller than the diameter of the connecting hole (10). The freezing temperature is determined according to the interference and the thermal expansion coefficient of the quartz glass, so that the gap after shrinkage is positive and does not exceed 5μm. The frozen and shrunken central column (2) is pushed into the connecting hole (10) axially with a clearance fit until the corresponding end face of the central column (2) is flush with the positioning plane; After returning to normal temperature, the central column (2) expands thermally and forms an interference fit with an interference of 0.001mm to 0.005mm between the mating surfaces. The uniform radial positive pressure is generated by the elastic deformation of the material to achieve damage-free locking.

6. The processing technology according to claim 4, characterized in that, When the fitting method is a conical fit, the connecting hole (10) is an inner conical hole (101) that is larger at the top and smaller at the bottom, and the outer wall of the central column (2) is machined with an outer conical surface (21) at the corresponding position that matches the taper of the inner conical hole (101), with a taper of 1:10 to 1:20; Step S4 specifically includes: Insert the outer conical surface (21) of the central column (2) into the inner conical hole (101) of the connecting hole (10); A controlled axial clamping force is applied to the central column (2), and the contact state of the conical surface is determined by monitoring the clamping force and displacement curve. During the clamping process, the outer conical surface (21) generates a centering restoring torque through the wedge action between the inner and outer conical surfaces, automatically guiding the central column (2) to be coaxial with the connecting hole (10). Continue to apply axial clamping force until the corresponding end face of the central column (2) abuts against the positioning plane and the force is stopped. The taper amplifies the axial clamping force proportionally into a radial locking force, and the taper satisfies the self-locking condition of the quartz-quartz friction pair. It remains locked after the axial clamping force is removed.

7. The processing technology according to claim 4, characterized in that, When the mating method is a threaded connection, the inner wall of the connecting hole (10) is machined with an internal thread (102), and the outer periphery of the central column (2) is machined with an external thread (22) at the corresponding position. Both the internal thread (102) and the external thread (22) are micro threads directly machined on the quartz glass material body; Step S4 specifically includes: Align the external thread (22) end of the central column (2) with the internal thread (102) entrance of the connecting hole (10). First, rotate the central column (2) slowly in the opposite direction without actively applying axial clamping force until the end face of the thread entrance generates an axial runout signal to confirm successful thread alignment. Screw the central column (2) in the forward direction. During the screwing process, keep the axis of the central column (2) parallel to the axis of the connecting hole (10). Use a screwing tool with a preset torque limit to screw in the thread. Stop screwing when the screwing torque reaches the preset limit. The preset torque limit is calculated and determined based on the allowable shear strength of the quartz material and the nominal diameter of the micro thread. The corresponding end face of the central column (2) is screwed in and abuts against the positioning plane, and the contact of the end face serves as a stop signal for the screwing in place; The engagement torque reaching a preset limit and the end face contact are designed to occur synchronously. When the torque reaches the limit before the end face contact, engagement stops and is determined to be an assembly abnormality.

8. The processing technology according to claim 4, characterized in that: In step S3, the vacuum annealing process includes: placing the hemispherical shell (1) and the central column (2) in a vacuum environment, heating them at a controlled rate to the annealing temperature range of quartz glass, holding them at the temperature for a preset time, and then slowly cooling them down to room temperature at a controlled rate. The residual stress introduced during the processing is eliminated through the above heating, holding, and slow cooling process, so that the material can be restored to a low stress background state before assembly.

9. The processing technology according to claim 4, characterized in that: In step S5, the overall micro-cutting finishing includes: performing micro-cutting on the inner spherical surface and / or outer spherical surface of the assembled hemispherical shell (1) to correct the coaxiality deviation between the center of symmetry of the hemispherical shell (1) and the axis of the central column (2) caused by assembly, so as to ensure that the coaxiality error between the center of symmetry of the final harmonic oscillator and the axis of the central column (2) is ≤0.005mm; The dynamic balancing includes: performing quality adjustment on the resonator blank by locally removing material to suppress frequency fragmentation caused by assembly stress or geometric asymmetry, reducing it to below a preset threshold.

10. The processing technology according to claim 7, characterized in that: The method for determining the preset torque limit is as follows: the maximum shear stress that the micro thread can withstand during engagement is calculated based on the allowable shear strength of the quartz material, and then the maximum shear stress is converted into an allowable engagement torque value in combination with the nominal diameter of the micro thread, and the allowable engagement torque value is used as the preset torque limit of the engagement tool; when the engagement torque reaches the preset limit, the engagement tool automatically stops applying torque to prevent the engagement torque from exceeding the bearing capacity of the thread and causing shear fracture at the thread root, and to prevent the central column (2) from being twisted off due to excessive torque.

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