Micro-shell vibration gyroscope, gyroscope vibrator and gyroscope vibrator preparation method

Abstract

The present invention belongs to the field of micro-shell gyroscopes, and specifically relates to a micro-shell gyroscope vibrator, including a shell and a metal film. The shell includes a cylindrical shell wall and a disc-shaped shell bottom that are interconnected. A boss is provided at the center of the shell bottom toward one side of the shell wall, and a groove is provided from the shell bottom to the center of the boss. The metal film covers at least the bottom surface of the shell bottom and the surface of the groove. The shell bottom of the gyroscope vibrator of the present invention is a planar structure and is coated with a metal film. The entire planar portion of the shell bottom is deformed by electrostatic drive to generate a standing wave mode, which can greatly increase the area of the drive / detection electrode, improve sensitivity and output signal-to-noise ratio. In addition, there is no need to coat the shell wall with a metal film. The area of the metal film is greatly reduced compared to the metal film area of a conventional semicircular structure gyroscope vibrator, thereby effectively reducing the damping and stress effects of the metal film, which has a significant effect on improving the quality factor of the structure, and thus has higher precision potential. In this way, it is achieved that the output signal-to-noise ratio is improved while having an extremely high quality factor potential.

Description

Technical Field

[0001] The present invention belongs to the field of micro-shell gyroscopes, and in particular relates to a micro-shell vibration gyroscope, a gyroscope vibrator and a method for preparing the gyroscope vibrator. Background Art

[0002] The micro-shell vibrating gyroscope (MSG) is a new type of micro-electromechanical (MEMS) gyroscope that has emerged in recent years. It is derived from the miniaturization of the traditional hemispherical shell vibrating gyroscope. It features a completely symmetrical structure, high precision, excellent reliability, and strong resistance to shock and vibration. When operating in rate integration mode, it can achieve extremely high measurement ranges without incurring scale factor nonlinearity, making it an ideal choice for high-dynamic, high-precision angular velocity measurement. It has applications in a variety of fields, including attitude measurement and control, and inertial navigation.

[0003] The micro-shell vibrating gyroscope is mainly composed of a vibrator, an electrode base and a drive detection circuit. Its vibrator is a highly symmetrical thin-walled shell, generally made of fused quartz material, with extremely small thermal expansion coefficient, thermal conductivity and damping coefficient, ensuring the high sensitivity and temperature stability of the structure.

[0004] For example, in patent CN105698780A, a micro-shell vibrating gyroscope and its preparation method, current vibrators are generally hemispherical in structure. To enable the vibrator to form a capacitor with the drive circuit on the electrode substrate, the following requirements must be met simultaneously: 1. A gap must be provided between the side lip of the hemispherical shell and the drive electrode; 2. The center of the hemispherical shell must be connected to the electrode substrate; and 3. The entire hemispherical shell must be metal-plated so that the side lip is connected to the electrode substrate through the metal coating. This presents two problems: 1. The side lip area corresponding to the planar electrode on the electrode substrate is small, resulting in a small area for the vibrator's drive / detection electrode and high output noise; 2. The metal coating area on the inner wall of the hemispherical shell accounts for a large proportion of the hemispherical shell's surface area. Since the damping coefficient of the metal film is much greater than that of the fused quartz structural layer, a micro-shell vibrating gyroscope with a high quality factor should minimize the coating area. However, under the existing structure, increasing the lip area will further increase the area of the metal coating, making it impossible to optimize the vibrator's drive / detection electrode area and the metal coating area simultaneously. Summary of the Invention

[0005] The technical problem to be solved by the present invention is to provide a micro-shell vibration gyroscope, a gyroscope vibrator and a method for preparing the gyroscope vibrator, in which the driving / detecting electrode area and the metal coating area are simultaneously optimized.

[0006] The present invention provides a micro-shell vibrating gyroscope vibrator, comprising a shell and a metal film. The shell comprises a cylindrical shell wall and a disc-shaped shell bottom connected to each other. A boss is provided at the center of the shell bottom toward one side of the shell wall. A groove is provided from the shell bottom to the center of the boss. The metal film at least covers the bottom surface of the shell bottom and the surface of the groove.

[0007] Furthermore, the housing is blow-molded from a single substrate.

[0008] Furthermore, the substrate is a fused quartz sheet.

[0009] Furthermore, the substrate has a thickness of 50 μm-200 μm.

[0010] Furthermore, the shell wall has a height of 5mm-10mm and a diameter of 8mm-11mm.

[0011] Furthermore, the connection between the shell wall and the shell bottom is an arc transition.

[0012] Furthermore, the metal film covers the arc at the connection between the shell wall and the shell bottom.

[0013] Furthermore, a skirt is provided on the side of the shell wall that extends outward away from the shell bottom.

[0014] The present invention also provides a method for preparing a micro-shell vibrating gyroscope vibrator, the method comprising the following steps:

[0015] The substrate is placed on the circular groove-shaped forming cavity and heated and softened by a heating device;

[0016] The molding cavity is vacuumed, and the softened substrate is deformed along the inner wall of the circular groove-shaped molding cavity until it is formed into a cylindrical shell wall, a disc-shaped shell bottom, a boss, and a groove;

[0017] The bottom surface of the shell and the surface of the groove are coated with a metal film by a coating device.

[0018] The present invention also provides a micro-shell vibrating gyroscope, comprising a micro-shell vibrating gyroscope vibrator and an electrode base, wherein the electrode base comprises a substrate, on which a plurality of fixed capacitor plates arranged in a circular array are provided, and a support column is protruding from the center of the plurality of fixed capacitor plates on the substrate, and the groove of the micro-shell vibrating gyroscope vibrator cooperates with the support column.

[0019] The beneficial effect of the present invention is that the shell bottom of the gyroscope vibrator of the present invention is a planar structure and is coated with a metal film. The entire flat part of the shell bottom is deformed by electrostatic drive to generate a standing wave mode, which can greatly increase the area of the drive / detection electrode, improve the sensitivity and output signal-to-noise ratio. In addition, there is no need to coat the shell wall with a metal film. At this time, the area of the metal film is greatly reduced compared to the metal film area of the conventional semicircular structure gyroscope vibrator, thereby effectively reducing the damping and stress effects of the metal film, which has a significant effect on improving the quality factor of the structure, and thus has higher precision potential. In this way, it is achieved while improving the output signal-to-noise ratio and having the potential for extremely high quality factors. In addition, since there is no need to coat the shell wall with a metal film, it is convenient to modulate the end of the shell wall by a laser. BRIEF DESCRIPTION OF THE DRAWINGS

[0020] Attachment Figure 1 It is a schematic structural diagram of the first angle of the gyroscope vibrator in the present invention.

[0021] Attachment Figure 2 It is a schematic diagram of the structure of the gyro vibrator at the second angle in the present invention.

[0022] Attachment Figure 3 It is a cross-sectional view of the gyro vibrator in the present invention.

[0023] Attachment Figure 4 It is a structural schematic diagram of the micro-shell vibrating gyroscope in the present invention.

[0024] Attachment Figure 5 Schematic diagram of the preparation process of the gyro vibrator in the present invention.

[0025] Attachment Figure 6 It is a structural schematic diagram of the forming mold in the present invention.

[0026] Attachment Figure 7 This is a schematic diagram showing the first angle of completion of the preparation of the gyro vibrator in the present invention.

[0027] Attachment Figure 8 This is a schematic diagram showing the second angle of completion of the preparation of the gyro vibrator in the present invention.

[0028] Attachment Figure 9 Schematic diagram of the modulation process of the gyro vibrator in the present invention.

[0029] In the figure, 1-shell; 11-shell wall; 12-shell bottom; 13-boss; 14-groove; 15-skirt; 2-metal film; 3-electrode base; 31-substrate; 32-fixed capacitor plate; 33-support column; 4-molding mold; 41-mold body; 42-molding cavity; 43-cylinder; 44-negative pressure through hole; 5-heating device; 6-laser; 7-substrate. DETAILED DESCRIPTION

[0030] The following will clearly and completely describe the technical solutions in the embodiments of the present invention in conjunction with the accompanying drawings. Obviously, the described embodiments are only part of the embodiments of the present invention, not all of the embodiments. All other embodiments obtained by ordinary technicians in this field based on the embodiments of the present invention without making any creative efforts shall fall within the scope of protection of the present invention.

[0031] It should be noted that all directional indications in the embodiments of the present invention (such as up, down, left, right, front, back, etc.) are only used to explain the relative position relationship, movement status, etc. between the various components under a certain specific posture (as shown in the accompanying drawings). If the specific posture changes, the directional indication will also change accordingly.

[0032] In addition, the terms "first," "second," and so on, used in this disclosure are for descriptive purposes only and should not be construed as indicating or implying relative importance or implicitly specifying the number of the technical features being referenced. Thus, a feature specified as "first" or "second" may explicitly or implicitly include at least one such feature. In the description of this disclosure, "plurality" means at least two, such as two or three, unless otherwise specifically defined.

[0033] In the present invention, unless otherwise specified or limited, the terms "connection" and "fixation" should be understood in a broad sense. For example, "fixation" can mean fixed connection, detachable connection, or integration; it can mean mechanical connection, electrical connection, physical connection, or wireless communication connection; it can mean direct connection or indirect connection through an intermediate medium; it can mean internal communication between two elements or interaction between two elements, unless otherwise specified. For those skilled in the art, the specific meanings of the above terms in the present invention can be understood according to specific circumstances.

[0034] In addition, the technical solutions between the various embodiments of the present invention can be combined with each other, but it must be based on the fact that ordinary technicians in this field can implement it. When the combination of technical solutions is mutually contradictory or cannot be implemented, it should be deemed that such a combination of technical solutions does not exist and is not within the scope of protection required by the present invention.

[0035] As attached Figure 1-9 As shown, the present invention provides a micro-shell vibrating gyroscope vibrator, including a shell 1 and a metal film 2. The shell 1 includes a cylindrical shell wall 11 and a disc-shaped shell bottom 12 connected to each other. The center of the shell bottom 12 is provided with a boss 13 protruding toward one side of the shell wall 11. The shell bottom 12 is provided with a groove 14 from the center of the boss 13. The metal film 2 covers at least the bottom surface of the shell bottom 12 and the surface of the groove 14.

[0036] The shell bottom 12 of the gyroscope vibrator of the present invention is a planar structure and is coated with a metal film 2. The entire planar portion of the shell bottom 12 is deformed by electrostatic drive to generate a standing wave mode, which can greatly increase the area of the drive / detection electrode, improve sensitivity and output signal-to-noise ratio; specifically, the effective capacitance area of the traditional micro-hemispherical resonator is only the bowl mouth area, while the entire shell bottom 12 of the gyroscope resonator provided by the present invention can be used for electrode drive or detection. The area of the multiple fixed capacitor plates 32 of the electrode base 3 matched with the present invention can also be increased synchronously. When the metal film 2 covers the bottom surface of the shell bottom 12 and the surface of the groove 14 and forms multiple high-efficiency capacitors with the multiple fixed capacitor plates 32 of the electrode base 3, due to its larger area, a greater driving force can be applied to detect weaker vibrations. In addition, the shell wall 11 does not need to be coated with a metal film 2. At this time, the area of the metal film 2 is greatly reduced compared to the area of the metal film 2 of the conventional semicircular structure gyroscope vibrator, thereby effectively reducing the damping and stress effects of the metal film 2, which has a significant effect on improving the structural quality factor, and thus has higher precision potential. This achieves the potential for extremely high quality factors while improving the output signal-to-noise ratio.

[0037] In addition, since the shell wall 11 does not need to be coated with the metal film 2, it is convenient to modulate the end of the shell wall 11 by the laser 6, thereby facilitating the improvement of the structural mass balance of the gyroscope oscillator. While modulating the end of the shell wall 11 to remove mass, the action position of the laser 6 is at a certain distance from the metal film 2, and therefore does not affect the metal film 2, thereby avoiding the situation where the metal film 2 is ablated due to excessive local temperature during the adjustment process of the laser 6. Compared with the hemispherical structure gyroscope oscillator that requires full coating, the gyroscope oscillator of the present invention is also greatly facilitated by adjustment while simultaneously improving the output signal-to-noise ratio and the quality factor.

[0038] The shell 1 is blow-molded through a base material 7. In this embodiment, the shell 1 can be made into a diameter less than 10 mm. Compared with traditional mechanical processing methods such as grinding and polishing, the volume of the gyroscope vibrator can be greatly reduced, and the material cost and processing cost can be reduced. At the same time, the shell 1 is blow-molded, and the connection parts between the shell wall 11 and the shell bottom 12, and the connection parts between the shell bottom 12 and the groove 14 in the shell 1 have smooth transitions. When the metal film 2 is plated, the thickness of the metal film 2 can be ensured to be uniform and the connection is uniform.

[0039] In one embodiment, the substrate 7 is a fused quartz sheet, wherein the thickness of the substrate 7 is 50 μm-200 μm, the height of the shell wall 11 is 5 mm-10 mm, and the diameter is 8 mm-11 mm, so that the size of the gyroscope vibrator meets the miniaturization requirements and is suitable for more application scenarios.

[0040] The connection between the shell wall 11 and the shell bottom 12 is an arc transition. In this embodiment, the arc transition is naturally formed during the blow molding process of the base material 7, which can avoid stress concentration and improve the structural strength of the shell 1.

[0041] The metal film 2 covers the arc at the connection between the shell wall 11 and the shell bottom 12, thereby increasing the electrode area.

[0042] The shell wall 11 is further extended outwardly to the side away from the shell bottom 12 to form a skirt 15. The skirt 15 is formed when the substrate 7 is blow-molded. When the excess mass block is cut off after blow-molding, part of the skirt 15 is retained, which greatly facilitates the adjustment of the mass balance of the gyro vibrator structure. Figure 9 As shown, after testing the gyro oscillator, the symmetry of the mass adjustment structure can be removed at skirt 15 using laser 6. Since skirt 15 is located at a distance from metal film 2, the high temperature of the laser 6 during mass adjustment does not affect the metal film 2, thus preventing ablation of the metal film 2 caused by localized overheating during the laser 6 adjustment process. Furthermore, skirt 15 can be used to optimize its topology. For example, by modulating it into a periodic corrugated structure, vibration sensitivity can be enhanced. This structural optimization is decoupled from the bottom electrode shape and has no impact on the area of the drive and detection electrodes, providing design flexibility.

[0043] The present invention also provides a method for preparing a micro-shell vibrating gyroscope vibrator, which uses a forming mold 4 and a heating device 5, wherein the heating device 5 is used to generate a high-temperature flame, wherein the forming mold 4 includes a mold body 41, and a circular groove-shaped forming cavity 42 is provided on the mold body 41, and a cylinder 43 is provided at the center of the bottom of the forming cavity 42, and a negative pressure through hole 44 is provided at the bottom of the forming cavity 42, which passes through the mold body 41, wherein the negative pressure through hole 44 is used to generate negative pressure in the forming cavity 42.

[0044] The method comprises the following steps:

[0045] S1, such as Figure 5 As shown, the substrate 7 is placed on the circular groove-shaped molding cavity 42, and the substrate 7 is heated and softened by the heating device 5;

[0046] S2, such as Figure 7 and Figure 8 As shown, the molding cavity 42 is evacuated through the negative pressure through hole 44, and the softened substrate 7 is deformed along the inner wall of the circular groove-shaped molding cavity 42 until it is formed into a cylindrical shell wall 11 and a disc-shaped shell bottom 12. The presence of the cylinder 43 forms a boss 13 and a groove 14 in the center of the shell bottom 12;

[0047] S3 , coating the bottom surface of the shell bottom 12 and the surface of the groove 14 with a metal film 2 using a coating device.

[0048] The present invention also provides a micro-shell vibrating gyroscope, comprising a micro-shell vibrating gyroscope vibrator and an electrode substrate 3, wherein the electrode substrate 3 comprises a base plate 31, on which a plurality of fixed capacitor plates 32 arranged in a circular array are provided, and a support column 33 is provided protruding from the base plate 31 at the center of the plurality of fixed capacitor plates 32, and the groove 14 of the micro-shell vibrating gyroscope vibrator cooperates with the support column 33. Figure 4 As shown, the fixed capacitor plates 32 are in the form of a plurality of fan-shaped structures in a ring array, which can effectively increase the area of the driving / detecting electrodes.

[0049] The contents not described in detail in this specification belong to the prior art known to professional and technical personnel in this field.

Claims

1. A micro-shell vibrating gyroscope vibrator, characterized in that: The invention comprises a shell (1) and a metal film (2), wherein the shell (1) comprises a cylindrical shell wall (11) and a disc-shaped shell bottom (12) connected to each other, a boss (13) is provided at the center of the shell bottom (12) protruding toward one side of the shell wall (11), a groove (14) is provided from the shell bottom (12) to the center of the boss (13), and the metal film (2) covers at least the bottom surface of the shell bottom (12) and the surface of the groove (14); The connection between the shell wall (11) and the shell bottom (12) is an arc transition, which is naturally formed during the substrate blowing process. The metal film (2) covers the arc at the connection between the shell wall (11) and the shell bottom (12), and the shell wall does not need to be plated with a metal film.

2. The micro-shell vibrating gyroscope vibrator according to claim 1, wherein: The housing (1) is blow-molded from a base material (7).

3. The micro-shell vibrating gyroscope vibrator according to claim 2, wherein: The substrate (7) is a fused quartz plate.

4. The micro-shell vibrating gyro vibrator according to claim 3, wherein: The thickness of the substrate (7) is 50 μm-200 μm.

5. The micro-shell vibrating gyroscope vibrator according to claim 3, wherein: The shell wall (11) has a height of 5mm-10mm and a diameter of 8mm-11mm.

6. The micro-shell vibrating gyroscope vibrator according to any one of claims 1 to 5, characterized in that: The shell wall (11) is further provided with a skirt (15) extending outward on the side facing away from the shell bottom (12).

7. A method for preparing a micro-shell vibrating gyroscope vibrator according to any one of claims 1 to 6, characterized in that: The method comprises the following steps: Placing a substrate (7) on a circular groove-shaped molding cavity (42), and heating and softening the substrate (7) by a heating device (5); The molding cavity (42) is vacuumed, and the softened substrate (7) is deformed along the inner wall of the circular groove-shaped molding cavity (42) until it is formed into a cylindrical shell wall (11), a disc-shaped shell bottom (12), a boss (13) and a groove (14); The metal film (2) is plated on the bottom surface of the shell bottom (12) and the surface of the groove (14) by using a coating device.

8. A micro-shell vibrating gyroscope, characterized in that: The invention comprises a micro-shell vibrating gyroscope vibrator according to any one of claims 1 to 6 and an electrode substrate (3), wherein the electrode substrate (3) comprises a base plate (31), a plurality of fixed capacitor plates (32) arranged in a ring array are provided on the base plate (31), a support column (33) is protruded from the center of the plurality of fixed capacitor plates (32), and a groove (14) of the micro-shell vibrating gyroscope vibrator cooperates with the support column (33).

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