CN114719852B - High overload resistant inertial system with elastic double-ring buffer structure - Google Patents

Abstract

The invention discloses an anti-high overload inertia system with an elastic double-ring buffer structure, which includes an outer protective shell, an inner main body protective structure, an inertial measurement unit, a connecting piece, first to second elastic buffer rings, and an end cover; the outer protective Two grooves are distributed symmetrically along the radial direction of the housing for installing the antenna, and the lower part of the outer side of the housing is provided with threads; the internal main body protection structure is used to withstand external overload impact and prevent external electromagnetic interference, and two through holes are distributed on the side of the cylinder to lead out the antenna; The inertial measurement unit is divided into three layers: the processor board, the inertial measurement unit board and the GNSS receiving board; the connector connects the inertial measurement unit and the internal main body protection structure; the first ~ second elastic buffer rings form an elastic double ring structure, which is used to connect the internal main body protection The structure and the outer protective shell; the end cover is used to provide axial support for the inner main protective structure. The invention enables the micro-electromechanical inertial measurement unit to meet application requirements in measurement accuracy before and after experiencing high overload impacts.

Description

An anti-high overload inertial system with elastic double-ring buffer structure

technical field

The invention belongs to the technical field of mechanical protection and vibration reduction of micro-electromechanical devices, and in particular relates to an anti-high overload inertial system with an elastic double-ring buffer structure.

Background technique

With the development of chip technology and micro-nano processing technology, MEMS devices are gradually applied to various fields, including the navigation field, such as the use of MEMS gyroscopes and accelerometers to form an inertial navigation unit, compared with traditional inertial sensors. Said that the micro-electromechanical inertial sensor has the advantages of small size, small mass, and high reliability. It is suitable for mass production and can break through space constraints. It is more suitable for small unmanned aerial vehicles and high-speed aircraft. Navigation needs.

In actual missile-borne applications, there are high G-value overload shocks and high-frequency angular vibrations at the moment of launch and impact of the carrier, which will have a serious impact on the measurement accuracy of MEMS inertial devices. Therefore, at present, a vibration reduction system is designed for the navigation components on the missile to absorb vibration and shock, so as to ensure the measurement accuracy of the inertial sensor. For the design of the vibration reduction system, it is necessary to meet the rationality of the space composition of the inertial measurement coordinate system, ensure the achievability and effectiveness of machining and surface treatment, and try to use simple and direct structural forms and assembly relationships to improve the reliability of the structure. At the same time, it should have good insulation, high structural strength, light weight and small volume. At present, the design of vibration reduction system for MEMS inertial measurement unit has been one of the research hotspots.

The existing damping structures for inertial measurement units mainly have the following problems:

1. Although the design coincides the elastic center of the vibration-damping structure with the geometric center of the system as a whole when determining the overall vibration-damping scheme of the system, it is difficult to ensure complete coincidence in the actual processing, production and assembly process, and the elastic center of the vibration-damping structure deviates from the design The scheme leads to the coupling between linear vibration and angular vibration of the system, which affects the measurement accuracy of the inertial measurement unit;

2. When designing the vibration damping structure, it is not considered that the natural frequency of the system itself is within the bandwidth range of the inertial measurement unit, which resonates with the input signal, causing the interference signal to be amplified, which seriously affects the measurement accuracy of the micro inertial measurement unit;

3. The rigidity in the three linear vibration directions of the system is not uniform, resulting in inconsistent frequencies in the three linear vibration directions, so that the natural frequency range of the system becomes too wide.

Contents of the invention

The purpose of the present invention is to provide an anti-high overload inertial system with an elastic double-ring buffer structure, so as to ensure that the measurement accuracy of the system before and after a high G value impact meets the requirements of the ballistic application.

The technical solution to realize the purpose of the present invention is: a high overload inertial system with an elastic double-ring buffer structure, including an outer protective shell, an inner main body protective structure, an inertial measurement unit, a connector, a first elastic buffer ring, a second Elastic buffer ring, end cap;

The outer protective shell is used to accommodate the MEMS inertial measurement device, and the shell is radially symmetrically distributed with two first grooves for installing the GNSS antenna, and the lower half of the outer shell is provided with a screw structure for the overall installation of the system on the carrier;

The internal main protection structure is a cylinder as a whole, which is used to withstand external overload impact and prevent external electromagnetic interference. Two through holes are distributed radially and equidistantly on the side of the cylinder to lead out the antenna;

The inertial measurement unit is divided into three layers, which are respectively a processor board, an inertial measurement unit board and a GNSS receiving board. The inertial measurement unit board is used to measure the inertial data of the carrier, the GNSS receiving board is used to obtain satellite data, and the processor board is used for Fusion data to calculate the attitude of the carrier;

The connecting piece is used to connect the inertial measurement unit and the internal main body protection structure. Eight through holes evenly distributed on the outside of the connection piece are connected to the internal main body protection structure by screws, and six threaded holes are evenly distributed on the inside to connect with the inertial measurement unit;

The first elastic buffer ring and the second elastic buffer ring form an elastic double-ring structure, and the elastic double-ring structure is used to connect the internal main body protection structure and the external protection shell, and limit the relative positional relationship between the internal main body protection structure and the external protection shell ;

The end cap is used to provide axial support for the inner main body protection structure.

Further, the outer protective shell is a cylindrical structure, which is made of oxidized alloy steel; the first boss is arranged inside the outer protective shell to support the elastic double-ring structure and the inner main body protective structure, and through the form of grooves Snap together to limit displacement and rotation of the inner body guard structure.

Further, the inner body protection structure is made of alloy steel and the surface of the structure is coated with antimagnetic material, and four second bosses are radially distributed on the side, and second grooves are arranged on the second bosses.

Further, the inertial measurement unit is divided into three layers, and the layers are electrically connected by flexible wires, and the mutual positions are fixed by copper pillars; a high-precision gyroscope and an accelerometer are arranged on the inertial measurement unit board, Make the sensors orthogonal to each other by installing the positioning holes.

Further, the connecting piece is made of alloy steel, and the outer through hole and the inner threaded hole are kept coaxial through numerical control machining.

Further, the elastic double-ring structure is distributed along the axial direction, and the elastic center of the elastic double-ring structure coincides with the geometric center of the internal main body protection structure; the first elastic buffer ring and the second elastic buffer ring have the same structure, and four symmetrical The distributed grooves are used to absorb high-frequency angular vibration, and four third bosses are evenly distributed along the circumference of the elastic buffer ring, and the third bosses are used to form a connection with the outer protective shell and the inner main body protective structure; the second The second groove provided on the boss is connected with the third boss to form a supporting structure.

Further, the end cover is connected with the external protective shell by screws to form a closed space for filling the potting material; four third grooves are evenly distributed on the protruding part of the end cover, and the third groove of the elastic buffer ring The bosses form a fit that limits the degrees of freedom of the elastic double ring structure.

Further, the first elastic buffer ring and the second elastic buffer ring are distributed along the axial direction, and the size of the third boss on the ring is the same as that of the first groove on the outer protective shell and the first groove on the inner main body protective structure. The size of the second groove and the third groove on the end cover are suitable, so that the internal body protection structure is limited between the first elastic buffer ring and the second elastic buffer ring, and the first elastic buffer ring, the second elastic buffer ring The ring and the inner main body protective structure are integrally connected to the outer protective shell to maintain the relative positional relationship between the inner main protective structure and the outer protective shell.

Further, there is a set gap between the outer protective shell and the upper end of the inner main protective structure, and a gap of the same size is set between the end cover and the inner main protective structure, and the size of the gap is larger than the maximum radial displacement of the inner main protective structure; the end cover and the inner main protective structure The second elastic buffer rings are kept in close contact and fastened with screws to limit the axial movement of the elastic buffer rings.

Further, the elastic center of the elastic double-ring structure coincides with the center of mass of the internal main body protection structure, specifically: ensuring the coaxiality of the elastic double-ring structure and the parallelism between the inner convex surface of the housing and the upper plane of the end cover, so that The elastic center is along the vertical direction and runs through the center of mass; at the same time, the screws are installed diagonally to ensure that the elastic double-ring structure is evenly stressed.

Compared with the prior art, the present invention has significant advantages in that:

1) The present invention uses an elastic double-ring buffer structure to protect the inertial components. Two elastic damping rings are distributed along the axial direction and form an interference fit with the main protection structure to ensure that the two elastic damping rings experience high overload impact It can play a protective role at all times, avoiding the poor effect of using a single damping ring; through the connection and cooperation between the boss on the elastic damping ring and the groove of the main protective structure, the vibration damping structure is reduced. The gap between the main protective structure and the main protective structure limits the movement of the main protective structure in the axial direction, so that the vibration-damping structure can fully absorb the load and ensure no deformation when experiencing high overload shocks, avoiding the distribution of multiple vibration-damping structures. The problem of poor stiffness;

2) There are four evenly distributed annular grooves on the side of the elastic damping ring of the present invention, and the radial symmetry of the elastic damping ring is ensured, which can effectively absorb high-frequency angular vibration, reduce the system frequency, and avoid exciting the natural vibration modes of sensitive devices , to prevent the impact on the measurement accuracy of the inertial measurement components; the elastic center of the elastic double-ring structure of the present invention coincides with the geometric distribution center of the MEMS inertial sensor, so as to avoid vibration in one direction of the system caused by eccentricity and vibration in another direction, which is easy System decoupling; at the same time, the symmetrical distribution ensures that the overall force of the vibration-damping structure is evenly distributed during the impact process, improving the overall anti-high overload capacity;

3) The main body protection junction of the present invention adopts the form of a central cavity to reduce the system stiffness and natural frequency of the system, so as to ensure that the displacement transmission rate is within the required range and improve the vibration reduction effect. In addition, the external protection shell adopts the method of screw connection It improves the connection strength between the system device and the carrier, and is more suitable for applications in high overload environments.

Description of drawings

Figure 1 is an exploded view of the vibration damping structure of the present invention.

Fig. 2 is a schematic diagram of the assembly of the vibration damping structure of the present invention.

Fig. 3 is the structural diagram of the elastic damping ring of the present invention

Fig. 4 is a cross-sectional view of the vibration damping structure of the present invention.

Fig. 5 is a partial enlarged view of the vibration damping structure.

The symbols in the figure include: outer protective shell 1, first boss 1-1, thread structure 1-2, first groove 1-3, inner convex surface 1-1-1 of the shell; first elastic buffer ring 2. The second elastic buffer ring 5, the third boss 2-1, the groove 2-2; the internal main body protection structure 3, the second groove 3-1, the through hole 3-2; the inertial measurement unit 4, the processor Board 4-1, IMU board 4-2 and GNSS receiving board 4-3; connector 6; end cover 7, third groove 7-1, end cover upper plane 7-1-1.

Detailed ways

It is easy to understand that, according to the technical solution of the present invention, without changing the essential spirit of the present invention, those skilled in the art can imagine various implementations of the present invention for protecting the micro-electromechanical inertial measurement unit in a high overload environment . Therefore, the following specific embodiments and drawings are only for exemplary illustration, and should not be regarded as the whole of the present invention or as a limitation or limitation on the technical solution of the present invention.

In combination with Figures 1 to 5, an anti-high overload inertial system with an elastic double-ring buffer structure of the present invention includes an outer protective shell 1, an inner main body protective structure 3, an inertial measurement unit 4, a connecting piece 6, and a first elastic buffer ring 2. The second elastic buffer ring 5, the end cover 7;

The outer protective shell 1 is used to accommodate the micro-electromechanical inertial measurement device 4, and the shell is symmetrically distributed along the radial direction with two first grooves 1-3 for installing the GNSS antenna, and the lower part of the outer shell is threaded to set the thread Structure 1-2, used to install the system as a whole on the carrier;

The internal main protection structure 3 is a cylinder as a whole, which can withstand external overload impact and prevent external electromagnetic interference. Two through holes 3-2 are distributed radially and equidistantly on the side of the cylinder for leading out the antenna;

The inertial measurement unit 4 is used to observe navigation information, and adopts a reliable algorithm to fuse the data and calculate the attitude of the carrier; the inertial measurement unit 4 is divided into three layers, which are respectively a processor board 4-1 and an inertial measurement unit Board 4-2 and GNSS receiving board 4-3, the inertial measurement unit board 4-2 is used to measure the inertial data of the carrier, the GNSS receiving board 4-3 is used to obtain satellite data, and the processor board 4-1 is used to fuse data, Calculate the attitude of the carrier;

The connecting piece 6 is used to connect the inertial measurement unit 4 and the internal main body protection structure 3. Eight through holes evenly distributed on the outside of the connecting piece 6 are connected with the internal main body protection structure 3 by screws, and six threaded holes are evenly distributed on the inside and the inertial The measuring unit 4 is connected;

The first elastic buffer ring 2 and the second elastic buffer ring 5 form an elastic double-ring structure, which is used to connect the internal main body protection structure 3 and the external protection shell 1, and limit the internal main body protection structure 3 and the external protection shell 1 The relative positional relationship between;

The end cap 7 is used to provide axial support for the inner body protection structure 3 .

Further, the outer protective shell 1 is a cylindrical structure, using alloy steel as the basic material, and undergoing oxidation treatment, which increases the hardness of the structure and improves the ability of the structure to resist stress changes in a high overload environment; the outer protective shell 1 is internally set The first boss 1-1 is used to support the elastic double-ring structure and the internal main body protection structure 3, and is clamped together in the form of a groove to limit the displacement and rotation of the internal main body protection structure 3; the lower half of the side of the external protection shell 1 Perform thread processing to improve the connection strength through the connection between the thread and the carrier;

Further, the internal main protective structure 3 adopts alloy steel as a whole as the main material to ensure the strength of the internal main protective structure. The surface of the structure is coated with anti-magnetic materials to improve the anti-electromagnetic interference capability of the system. Two sides of the internal main protective structure 3 are processed with two suitable Through the hole 3-2, the GNSS antenna is led out through the through hole 3-2; four second bosses are distributed along the radial direction on the side, and the second groove 3-1 and the boss on the elastic double ring structure are processed on the second boss. The platform is connected to form a support structure;

Further, the inertial measurement unit 4 is divided into three layers, and the layers are electrically connected by flexible wires, and the mutual positions are fixed by copper pillars; three uniaxial Gyroscopes and accelerometers, in order to ensure that the system accurately measures the inertial data of the carrier in three-dimensional space, the gyroscopes and accelerometers for measuring the z-axis are installed on the horizontal inertial device board, and the gyroscopes and accelerometers for the other two axes are arranged vertically The form of the inertial device board is installed to ensure that the three-axis sensors are orthogonal to each other. In order to improve the installation accuracy of the sensor, three positioning holes are processed on the inertial device board for positioning during installation;

Further, the connecting piece 6 is made of alloy steel material, and the coaxiality between the outer through hole and the inner threaded hole is ensured through numerical control machining, and the thickness of the connecting piece is thick enough to ensure the reliability of the connection;

Further, the elastic double-ring structure is distributed along the axial direction, and ensure that the elastic center of the elastic double-ring structure coincides with the geometric center of the inner main body protection structure 3 to avoid vibration coupling; the first elastic buffer ring 2 and the second elastic buffer ring 5 have the same structure, Four symmetrically distributed grooves 2-2 are arranged on the sides to absorb high-frequency angular vibration, and four third bosses 2-1 are evenly distributed along the circumference of the elastic buffer ring, and the third bosses 2-1 are used for It forms a connection and cooperation with the outer protective shell 1 and the inner main body protective structure 3; the second groove 3-1 provided on the second boss is connected with the third boss 2-1 to form a supporting structure.

Further, the end cap 7 is connected with the external protective shell 1 by screws to form a closed space for filling the potting material; the protruding part of the end cap 7 is evenly distributed with four third grooves 7-1, which are connected with the elastic buffer The third boss 2-1 of the ring forms a fit to limit the degree of freedom of the elastic double ring structure and ensure the reliability of the system.

The present invention will be described in further detail below in conjunction with the accompanying drawings and specific embodiments.

Example

Referring to Figure 1, Figure 2 and Figure 3, as a preferred embodiment of the present invention, it includes an outer protective shell 1, a first elastic buffer ring 2, a second elastic buffer ring 5, a main body protection structure 3, and an inertial measurement unit 4. The inertial measurement unit connector 6 and the end cover 7; the outer protective shell 1 is used to accommodate the micro-electromechanical inertial measurement unit, and there is a boss structure 1-1 inside to limit the position of the elastic double-ring structure, and the side of the cylinder is distributed Two symmetrical grooves 1-3 are used to install the GNSS antenna; the first elastic buffer ring 2 and the second elastic buffer ring 5 are distributed along the axial direction, and the size of the protrusion 2-1 on the ring is the same as that of the housing 1 The size of the groove on the top, the groove 3-1 on the main body protection structure 3 and the groove 7-1 on the end cover 7 are adapted, so that the main body protection structure 3 can be limited to the first elastic buffer ring 2, the second elastic between the buffer rings 5, and the first elastic buffer ring 2, the second elastic buffer ring 5 and the main protective structure 3 are integrally connected to the outer protective shell 1 to ensure the relative relationship between the main protective structure 3 and the shell 1. Positional relationship; the main protective structure 3 is a cylinder as a whole, and two through holes 3-2 are distributed on the side of the cylinder for leading out the antenna; the inertial measurement unit 4 is composed of a processor board 4-1, an inertial measurement unit board 4-2 and GNSS receiving board 4-3, used to measure the carrier navigation information and solve the carrier attitude; the inertial measurement unit connector 6 is used to connect the inertial measurement unit 4 and the internal main body protection frame 3, and its outer side is evenly distributed The eight through holes are connected with the internal main body protection frame by screws, and the six threaded holes are evenly distributed on the inside to connect with the inertial measurement unit 4; the end cover 7 is used to provide axial support for the internal main body protection structure; the end cover 7 and The shell 1 forms a closed space for potting;

In conjunction with Fig. 2, as a preferred embodiment, there should be a certain gap between the upper end of the housing 1 and the main protective structure 3, and there should also be a gap of the same size between the end cover 7 and the main protective structure 3, and the size of the gap should be larger than that of the main protective structure. to avoid contact with the end cover during vibration and affect the measurement accuracy; the end cover 7 is in close contact with the elastic buffer ring 5 and fastened with screws to limit the axial movement of the elastic buffer ring ;

With reference to Fig. 2, Fig. 3 and Fig. 4, as a preferred embodiment, the first elastic buffer ring 2 and the second elastic buffer ring 5 are made of titanium alloy, and the shape and structure of the elastic buffer ring are optimized by means of finite element analysis , it is calculated that the elastic buffer ring should adopt a radially symmetrical structure to ensure that all parts are evenly stressed during the impact process, enhance the ability to absorb periodic vibrations, and reduce the frequency close to the natural frequency of the MEMS inertial sensitive device itself. The effect of vibration on the measurement accuracy of inertial sensors. The side of the elastic double-ring structure adopts four symmetrically distributed grooves 2-2. Without destroying the radial symmetry of the elastic buffer ring, the contact area between the elastic buffer ring and the potting material is increased, and the potting material can be better used. The sealing material absorbs the impact load;

As a preferred embodiment, the method of making the elastic center of the elastic double-ring structure coincide with the center of mass of the internal main body protection structure is as follows: ensure the coaxiality of the elastic double-ring structure and the inner convex surface 1-1-1 of the housing and the upper plane of the end cover The parallelism between 7-1-1 makes the elastic center run through the center of mass along the vertical direction; at the same time, when installing the screws, adopt a diagonal installation method to ensure that the double-ring structure is evenly stressed, as shown in Figure 5.

As a preferred embodiment, for this example, six threaded holes are used to connect the IMU to the IMU. In fact, the IMU connector can be designed by itself according to different requirements;

Referring to Figure 1, Figure 2, Figure 3, as a preferred embodiment, when assembling, the inertial measurement unit 4 is first installed on the connector 6, and then the connector is installed on the inner protective frame by screws to complete the assembly of the inner protective frame . Then install the elastic buffer ring 2 on the groove of the shell 1, and then align the groove 3-1 of the main protective structure with the protrusion 2-1 on the elastic buffer ring 2 for installation, and then pass the groove and the protrusion Install the elastic buffer ring 5 and the end cover 7 in sequence, and finally connect them tightly with screws. The threaded structure 1-2 on the outer protective shell installs the system as a whole on the carrier.

The invention adopts the elastic double-ring buffer structure to protect the inertial components, and the two elastic damping rings are distributed along the axial direction to form an interference fit with the main body protection structure, so as to ensure that the two elastic damping rings are not damaged when experiencing high overload shocks. It can play a protective role, avoiding the situation where the vibration damping effect of a single damping ring is not good; through the connection and cooperation between the boss on the elastic damping ring and the groove of the main protective structure, the vibration damping structure and the main body are reduced. The gap between the protective structures restricts the movement of the main protective structure in the axial direction, so that the vibration-damping structure can fully absorb the load and ensure no deformation when experiencing high overload shocks, and avoids poor stiffness when multiple vibration-damping structures are distributed. The problem;

The side of the elastic damping ring of the present invention has four evenly distributed annular grooves, and ensures the radial symmetry of the elastic damping ring, which can effectively absorb high-frequency angular vibration, reduce the system frequency, avoid exciting the natural vibration modes of sensitive devices, and prevent It has an impact on the measurement accuracy of inertial measurement components; the elastic center of the elastic double-ring structure of the present invention coincides with the geometric distribution center of the micro-electromechanical inertial sensor, avoiding the vibration in one direction of the system caused by eccentricity and causing vibration in another direction, which is easy for the system to solve Coupling; at the same time, the symmetrical distribution ensures that the overall force of the vibration-damping structure is evenly distributed during the impact process, improving the overall anti-high overload capacity;

The main body protection junction of the present invention adopts the form of a central cavity to reduce the system stiffness and natural frequency of the system, thereby ensuring that the displacement transmission rate is within the required range and improving the vibration reduction effect. The connection strength between the system device and the carrier is more suitable for applications in high overload environments.

Finally, it should be noted that: the above-described embodiments are only specific implementations of the present invention, used to illustrate the technical solutions of the present invention, rather than limiting them, and the scope of protection of the present invention is not limited thereto, although referring to the foregoing The embodiment has described the present invention in detail, and those of ordinary skill in the art should understand that any person familiar with the technical field can still modify the technical solutions described in the foregoing embodiments within the technical scope disclosed in the present invention Changes can be easily thought of, or equivalent replacements are made to some of the technical features; and these modifications, changes or replacements do not make the essence of the corresponding technical solutions deviate from the spirit and scope of the technical solutions of the embodiments of the present invention, and should be included in the scope of the present invention within the scope of protection. Therefore, the protection scope of the present invention should be based on the protection scope of the claims.

Claims (7)

1. The anti-overload inertial system with the elastic double-ring buffer structure is characterized by comprising an outer protective shell (1), an inner main body protective structure (3), an inertial measurement unit (4), a connecting piece (6), a first elastic buffer ring (2), a second elastic buffer ring (5) and an end cover (7);

the outer protective shell (1) is used for accommodating a micro-electromechanical inertial measurement device (4), two first grooves (1-3) are symmetrically distributed in the radial direction of the shell and used for installing a GNSS antenna, and a thread structure (1-2) is arranged at the lower half part of the outer side of the shell and used for integrally installing the system on a carrier;

the inner main body protection structure (3) is integrally a cylinder and is used for bearing external overload impact and preventing external electromagnetic interference, and two through holes (3-2) are radially and equidistantly distributed on the side surface of the cylinder and are used for leading out an antenna;

the inertial measurement unit (4) is divided into three layers, namely a processor board (4-1), an inertial measurement unit board (4-2) and a GNSS receiving board (4-3), wherein the inertial measurement unit board (4-2) is used for measuring inertial data of a carrier, the GNSS receiving board (4-3) is used for acquiring satellite data, and the processor board (4-1) is used for fusing the data and calculating the posture of the carrier;

the connecting piece (6) is used for connecting the inertial measurement unit (4) with the internal main body protection structure (3), eight through holes are uniformly distributed on the outer side of the connecting piece (6) and are connected with the internal main body protection structure (3) by adopting screws, and six threaded holes are uniformly distributed on the inner side of the connecting piece to be connected with the inertial measurement unit (4);

the first elastic buffer ring (2) and the second elastic buffer ring (5) form an elastic double-ring structure, and the elastic double-ring structure is used for connecting the inner main body protection structure (3) and the outer protection shell (1) and limiting the relative position relationship between the inner main body protection structure (3) and the outer protection shell (1);

the end cap (7) is used for providing axial support for the inner main body protection structure (3);

the outer protective shell (1) is of a cylindrical structure and adopts alloy steel subjected to oxidation treatment; the inner part of the outer protective shell (1) is provided with a first boss (1-1) for supporting the elastic double-ring structure and the inner main body protective structure (3) and is clamped together in a groove mode to limit the displacement and rotation of the inner main body protective structure (3);

the inner main body protection structure (3) is made of alloy steel, the surface of the structure is coated with antimagnetic materials, four second bosses are radially distributed on the side surface, and second grooves (3-1) are formed in the second bosses;

the elastic double-ring structures are distributed along the axial direction, and the elastic center of the elastic double-ring structures coincides with the geometric center of the internal main body protection structure (3); the first elastic buffer ring (2) and the second elastic buffer ring (5) have the same structure, four symmetrically distributed grooves (2-2) are respectively arranged on the side surfaces and used for absorbing high-frequency angular vibration, four third bosses (2-1) are uniformly distributed on the elastic buffer ring along the circumference, and the third bosses (2-1) are used for forming connection fit with the outer protective shell (1) and the inner main body protective structure (3); and a second groove (3-1) arranged on the second boss is connected with the third boss (2-1) to form a supporting structure.

2. The anti-overload inertial system with the elastic double-ring buffer structure according to claim 1, wherein the inertial measurement unit (4) is divided into three layers, and the layers are electrically connected by flexible wires and are mutually fixed in position by copper columns; the inertial measurement unit board (4-2) is provided with a high-precision gyroscope and an accelerometer, and the sensors are mutually orthogonal in pairs through the installation of positioning holes.

3. The anti-overload inertial system with the elastic double-ring buffer structure according to claim 1, wherein the connecting piece (6) is made of alloy steel material, and the outer through hole and the inner threaded hole are kept coaxial by numerical control machining.

4. The anti-high overload inertial system with the elastic double-ring buffer structure according to claim 1, wherein the end cover (7) and the external protective shell (1) are connected by adopting screws to form a closed space for filling potting materials; four third grooves (7-1) are uniformly distributed on the protruding part of the end cover (7) and are matched with the third boss (2-1) of the elastic buffer ring, so that the degree of freedom of the elastic double-ring structure is limited.

5. The anti-high overload inertial system with the elastic double-ring buffer structure according to claim 4, wherein the first elastic buffer ring (2) and the second elastic buffer ring (5) are distributed along the axial direction, the third boss (2-1) on the ring is sized to be matched with the first groove (1-3) on the outer protection shell (1), the second groove (3-1) on the inner main body protection structure (3) and the third groove (7-1) on the end cover (7), so that the inner main body protection structure (3) is limited between the first elastic buffer ring (2) and the second elastic buffer ring (5), and the first elastic buffer ring (2), the second elastic buffer ring (5) and the inner main body protection structure (3) are integrally fixed on the outer protection shell (1), and the relative position relationship between the inner main body protection structure (3) and the outer protection shell (1) is maintained.

6. The anti-high overload inertial system with the elastic double-ring buffer structure according to claim 5, wherein a set gap is reserved between the upper ends of the outer protective shell (1) and the inner main body protective structure (3), a gap with the same size is arranged between the end cover (7) and the inner main body protective structure (3), and the size of the gap is larger than the maximum radial displacement of the inner main body protective structure (3); the end cap (7) is held in close contact with the second elastic buffer ring (5) and tightened with a screw to limit axial movement of the elastic buffer ring.

7. The anti-high overload inertial system with elastic double-ring buffer structure according to claim 6, characterized in that the elastic center of the elastic double-ring structure coincides with the centroid of the internal body protection structure (3), in particular: the coaxiality of the elastic double-ring structure and the parallelism between the convex surface (1-1-1) in the shell and the upper plane (7-1-1) of the end cover are ensured, so that the elastic center runs through the mass center along the vertical direction; meanwhile, a diagonal mounting mode is adopted when the screw is mounted, so that the stress uniformity of the elastic double-ring structure is ensured.

Images