Broadband vibration isolator with periodic structure

文档序号:1812820 发布日期:2021-11-09 浏览:21次 中文

阅读说明:本技术 一种含周期结构的宽频隔振器 (Broadband vibration isolator with periodic structure ) 是由 刘海平 张世乘 吕琦 于 2021-07-09 设计创作,主要内容包括:本发明提供一种含周期结构的宽频隔振器,属于隔振技术领域。该隔振器包括变截面薄片梁、周期结构、连接件、压盖、基座和底座,变截面薄片梁头部与连接件下端面使用M5螺钉相连;薄片梁尾部与基座上端面使用M5螺栓相连;连接件上端面与压盖使用M5螺钉相连;周期结构与连接件通过周期结构上端面通孔的M6螺栓相连;橡胶填充在周期结构内部,周期结构与橡胶通过灌胶工艺相配合。基座上端面和连接件下端面都加工为斜置平面,便于使用螺钉与变截面薄片梁连接;周期结构下端面与底座利用M5螺栓固连。变截面薄片梁通过弯曲产生垂直方向的负刚度,周期结构提供正刚度,二者组合形成宽频隔振系统,降低峰值频率;周期结构中的橡胶提供阻尼,降低响应峰值。(The invention provides a broadband vibration isolator with a periodic structure, and belongs to the technical field of vibration isolation. The vibration isolator comprises a variable cross-section thin sheet beam, a periodic structure, a connecting piece, a gland, a base and a base, wherein the head of the variable cross-section thin sheet beam is connected with the lower end face of the connecting piece by using an M5 screw; the tail part of the thin plate beam is connected with the upper end surface of the base by using an M5 bolt; the upper end surface of the connecting piece is connected with the gland through an M5 screw; the periodic structure is connected with the connecting piece through an M6 bolt of a through hole on the upper end face of the periodic structure; the rubber is filled in the periodic structure, and the periodic structure is matched with the rubber through a glue pouring process. The upper end surface of the base and the lower end surface of the connecting piece are processed into inclined planes, so that the base and the connecting piece can be conveniently connected with the variable cross-section thin sheet beam by using screws; the lower end face of the periodic structure is fixedly connected with the base through M5 bolts. The variable cross-section thin sheet beam generates negative rigidity in the vertical direction through bending, the periodic structure provides positive rigidity, and the negative rigidity and the positive rigidity are combined to form a broadband vibration isolation system so as to reduce peak frequency; the rubber in the periodic structure provides damping and reduces the response peak.)

1. The utility model provides a broadband isolator that contains periodic structure which characterized in that: the vibration isolation device comprises a variable cross-section sheet beam (1), a periodic structure (2), a connecting piece (3), a gland (4), a base (5) and a base (6), wherein the lower end face of the base (5) is fixed on the base (6) through an M5 bolt (7), the upper end face of the base (5) is connected with the tail of the variable cross-section sheet beam (1) through an M5 bolt (7), the head of the variable cross-section sheet beam (1) is connected with the lower end face of the connecting piece (3) through an M5 screw (9), a cavity in the connecting piece (3) is used for placing a connecting part needing to be isolated from a vibration object, the gland (4) at the upper part of the connecting piece (3) is used for fixing, and the gland (4) is connected with the connecting piece (3) through an M5 screw (9); a through hole is reserved from the inner cavity of the connecting piece (3) to the lower end face of the connecting piece (3), and an M6 bolt (10) penetrates through the through hole to connect the periodic structure (2) with the connecting piece (3); the periodic structure (2) is fixed on the base (6) through an M5 bolt (7); the rubber (11) is filled in the periodic structure (2), and the periodic structure (2) is matched with the rubber (11) through a glue pouring process; a spring washer (8) is arranged at the joint of the M5 screw for preventing looseness; a spring washer (8) is arranged at the bolt joint of the M5 for preventing looseness.

2. The broadband vibration isolator with periodic structure according to claim 1, wherein: the widths of the upper end faces of the variable cross-section thin sheet beam (1) and the base (5) are the same, and the variable cross-section thin sheet beam (1) is made of a material with yield strength larger than 1600MPa and tensile strength larger than 1800 MPa; the base (5) is made of a material with good plasticity and easy processing.

3. The broadband vibration isolator with periodic structure according to claim 1, wherein: the periodic structure (2) is a structure with a gap in the middle and integrally processed by 3D printing, and the periodic structure (2) is made of an alloy material with the tensile strength of more than 480MPa and the Mo content of 3%; the number of layers of the periodic structure (2) is not less than 2; and each layer is divided into n parts by not less than 2 supporting columns (12), wherein n is not less than 2, and each part is internally filled with rubber (11).

4. The broadband vibration isolator with periodic structure according to claim 1, wherein: the upper end face of the base (5) and the lower end face of the connecting piece (3) are processed into inclined planes, so that the M5 screw (9) can be conveniently connected with the variable-section thin-sheet beam (1).

5. The broadband vibration isolator with periodic structure according to claim 1, wherein: the variable cross-section thin sheet beam (1) is replaced by a constant cross-section thin sheet beam according to the vibration isolation requirement; the spring washer (8) is replaced by one of a stop washer and a self-locking nut for anti-loosening according to actual requirements.

6. The broadband vibration isolator with periodic structure according to claim 1, wherein: the variable cross-section thin sheet beams (1) are arranged in an axial array, and at least 6 groups of mounting positions are arranged.

7. The broadband vibration isolator with periodic structure according to claim 1, wherein: and a piezoelectric material (13) is arranged between the connecting piece (3) and the periodic structure (2), and the piezoelectric material (13) is externally connected with an energy consumption circuit (14), so that the damping characteristic of the system is improved, and active control is realized.

8. The broadband vibration isolator with periodic structure according to claim 1, wherein: the piezoelectric material (13) is adhered to the lower end face of the variable cross-section thin sheet beam (1), when the variable cross-section thin sheet beam (1) displaces, the piezoelectric material (13) is driven to displace, and the piezoelectric material (13) is externally connected with an energy consumption circuit (14).

9. The broadband vibration isolator with periodic structure according to claim 1, wherein: the periodic structure (2) is replaced by a spring (15), a coil (16) is arranged outside the spring (15), the upper end of the coil (16) is connected with the lower end face of the connecting piece (3), the lower end of the coil (16) is suspended, m groups of annular magnets (17) are arranged on the inner wall of the base (6), m is larger than or equal to 4, when the vibration isolator generates displacement in the working stage, the coil (16) moves relative to the magnets (17), voltage is generated in the coil (16), the coil (16) is externally connected with an energy consumption circuit (14), the damping characteristic of the system is improved, and active control is achieved.

10. The broadband vibration isolator with periodic structure according to claim 1, wherein: the section sheet beam (1) and the rubber (11) in the periodic structure (2) provide rigidity and damping when the periodic structure (2) is subjected to static pressure or the vibration isolation system is subjected to external environment disturbance, and the requirement of broadband high-stability vibration isolation of the system is met.

Technical Field

The invention relates to the technical field of vibration isolation, in particular to a broadband vibration isolator with a periodic structure.

Background

In the fields of aerospace satellite, precision machinery, photoelectric detection, medical instruments, laser ranging and other important engineering, vibration control is always one of the key points of engineering research. With the rapid development of economy, the requirement of the engineering field on the vibration isolation of equipment is higher and higher, and especially in some high-precision fields, the vibration of the surrounding environment, such as personnel walking, road driving, operation of large-scale equipment, installation and debugging, can affect the stability of the equipment performance and the accuracy of testing, and even cause irreversible damage. In order to ensure the stability of the equipment, the vibration isolation control is needed. The common vibration isolator generally adopts a linear vibration isolator such as a spring vibration isolator or a rubber vibration isolator, and the linear vibration isolator has the advantages of large static compression amount, lower natural frequency and good low-frequency vibration isolation performance. However, if the static pressure load of the equipment is too large, the linear vibration isolator has larger deformation, so that the stability of the equipment is greatly reduced, and even the safety of the equipment is irreversibly damaged. The stability of the equipment can be ensured when the equipment is subjected to a large static load; meanwhile, when the equipment vibrates due to the disturbance of the surrounding environment, the vibration isolation effect which is as good as possible can be ensured through the vibration isolator. Therefore, it is very important to make the vibration isolator have high static stiffness and simultaneously meet low dynamic stiffness so as to realize high static stiffness and low dynamic stiffness and obtain smaller natural frequency. Therefore, the development of the broadband vibration isolator has important significance for protecting high-precision equipment and improving the working stability of the high-precision equipment.

Disclosure of Invention

The technical problem to be solved by the invention is to provide a broadband vibration isolator with a periodic structure, which is used as a broadband vibration reduction and isolation device with high stability and can realize high static and low dynamic, namely: the static rigidity of the vibration isolator is increased, so that the static deformation is effectively reduced; meanwhile, the dynamic stiffness of the vibration isolator is effectively reduced, and the good vibration isolation performance of the vibration isolator and the stability of working equipment are ensured. The variable cross-section thin sheet beam is adopted to provide negative rigidity, the periodic structure provides positive rigidity, the broadband vibration isolator is combined, and meanwhile, the periodic structure also has a band gap characteristic, so that the vibration reduction and isolation performance of the periodic structure can be further enhanced. The vibration isolator is installed on equipment, so that vibration caused by the surrounding environment is effectively isolated, and the vibration isolator is stable in vibration isolation, high in reliability, simple in structure and convenient to install. The problem of unstable vibration isolation performance in the prior art is solved by improving the static stiffness of the vibration isolator and reducing the dynamic stiffness of the vibration isolator.

The vibration isolator comprises a variable cross-section thin sheet beam, a periodic structure, a connecting piece, a gland, a base and a base, wherein the lower end face of the base is fixed on the base through an M5 bolt, the upper end face of the base is connected with the tail of the variable cross-section thin sheet beam through an M5 bolt, the head of the variable cross-section thin sheet beam is connected with the lower end face of the connecting piece through an M5 screw, a cavity in the connecting piece is used for placing a connecting part of an object to be isolated and vibrated, the connecting part is fixed through the gland on the upper part of the connecting piece, and the gland is connected with the connecting piece through an M5 screw; through holes are reserved from the inner cavity of the connecting piece to the lower end face of the connecting piece, and M6 bolts penetrate through the through holes to connect the periodic structure with the connecting piece; the periodic structure is fixed on the base through M5 bolts; the rubber is filled in the periodic structure, and the periodic structure is matched with the rubber through a glue pouring process; a spring washer is arranged at the joint of the M5 screw for preventing looseness; the M5 bolt joint is provided with a spring washer for preventing looseness.

The widths of the upper end faces of the variable cross-section thin sheet beam and the base are the same, and the thickness and the length of the variable cross-section thin sheet beam can be adjusted according to specific requirements. The variable cross-section thin-sheet beam is made of material with yield strength more than 1600MPa and tensile strength more than 1800MPa, such as 60Si2CrVA, which is helpful for vibration reduction and can provide negative rigidity; the base is made of a material which is good in plasticity and easy to process, such as 10F.

The periodic structure is a structure with a gap in the middle and integrally processed by 3D printing, and is made of an alloy material with the tensile strength of more than 480MPa and the Mo content of 3 percent, such as 316L stainless steel; the number of the periodic structure layers is not less than 2; and each layer is divided into n parts by at least 2 supporting columns, wherein n is more than or equal to 2, rubber is filled in each part, the selection of rubber materials can be adjusted according to specific working conditions, and the selection is based on indexes such as elastic modulus, Poisson's ratio, damping ratio and the like of the rubber.

The upper end surface of the base and the lower end surface of the connecting piece are processed into inclined planes, so that M5 screws can be conveniently used to be connected with the variable-section sheet beam, and the angle of the inclined planes can be changed according to specific requirements.

The variable cross-section sheet beam is replaced by the constant cross-section sheet beam according to the vibration isolation requirement; the spring washer is replaced by one of a stop washer and a self-locking nut for anti-loosening according to actual requirements.

The variable cross-section thin sheet beams are axially arranged in an array mode, at least 6 groups of installation positions are arranged, and the number of the variable cross-section thin sheet beams can be adjusted according to specific vibration reduction and isolation requirements.

And a piezoelectric material is arranged between the connecting piece and the periodic structure, and is externally connected with an energy dissipation circuit, so that the damping characteristic of the system is improved, and active control is realized.

The piezoelectric material is pasted on the lower end face of the variable cross-section thin sheet beam, when the variable cross-section thin sheet beam displaces, the piezoelectric material is driven to displace, and the piezoelectric material is externally connected with an energy consumption circuit.

The periodic structure is replaced by a spring, a coil is arranged outside the spring, the upper end of the coil is connected with the lower end face of the connecting piece, the lower end of the coil is suspended, m groups of annular magnets are arranged on the inner wall of the base, m is larger than or equal to 4, when the vibration isolator generates displacement in the working stage, the coil makes relative motion relative to the magnets, voltage is generated in the coil, the coil is externally connected with an energy dissipation circuit, the damping characteristic of the system is improved, and active control is achieved.

The rigidity and the damping are provided by the thin sheet beam with the time-varying section and the rubber in the periodic structure when the periodic structure is subjected to static pressure or the vibration isolation system is subjected to external environment disturbance, and the requirement of wide-frequency and high-stability vibration isolation of the system is met.

The technical scheme of the invention has the following beneficial effects:

1. the periodic structure is adopted as a supporting structure, and the rubber is filled in the inner gap of the periodic structure, so that the periodic structure has proper rigidity and damping.

2. The variable cross-section thin sheet beam and the periodic structure are combined and installed, so that negative rigidity in the vertical direction is generated through bending of the variable cross-section thin sheet beam, and compared with the horizontal compression bar, the inclined linear spring, the Euler bent beam and other forms, the creep resistance of the variable cross-section thin sheet beam is better, the light weight is easy to realize, and the high-frequency vibration isolation performance of the system is effectively improved.

3. According to the invention, the periodic structure and the variable cross-section sheet beam are combined and mounted, the periodic structure provides positive rigidity, the variable cross-section sheet beam provides negative rigidity in the vertical direction, and the periodic structure and the variable cross-section sheet beam are combined to form the broadband vibration isolation system, so that the response peak value is effectively reduced, and broadband high-stability vibration isolation is realized.

4. The invention has simple structure, convenient installation, reliable work, easy replacement of parts, relatively independent rigidity and damping of the vibration isolator, and can increase the number of the sheet beams according to the vibration isolation requirement, so that the vibration isolation effect of the system is more stable.

5. The invention can reasonably design the structural parameters according to different vibration isolation requirements, improve the working efficiency of the vibration isolator and realize the adjustability of the amplitude attenuation performance.

6. The invention can be popularized and applied in the field of high-precision engineering vibration isolation, and effectively increases the static rigidity of the vibration isolation system, thereby reducing the static deformation of the vibration isolation system and enhancing the stability of the system; meanwhile, when high-frequency vibration is guaranteed, low dynamic stiffness is provided, the characteristic of high static and low dynamic is realized, and the requirement of wide-frequency and high-stability vibration isolation of a system is met.

7. The gland and the connecting piece device used by the invention can be conveniently connected with an object needing vibration isolation, and have the advantages of simple structure, no need of maintenance, cost saving, reliable work, long service life and strong practicability.

8. The invention can realize active and passive control by combining various schemes according to specific vibration isolation requirements.

Drawings

FIG. 1 is a schematic structural diagram of the appearance of the broadband vibration isolator including a periodic structure according to the present invention;

FIG. 2 is an isometric view of the broadband vibration isolator including periodic structures according to the present invention;

FIG. 3 is a cross-sectional view of the broadband vibration isolator including a periodic structure according to the present invention;

FIG. 4 is an isometric view of a periodic structure of the present invention;

FIG. 5 is a cross-sectional view of a first embodiment of the vibration isolator incorporating piezoelectric material in accordance with the present invention;

FIG. 6 is a sectional view of a second embodiment of the vibration isolator incorporating piezoelectric material in accordance with the present invention;

fig. 7 is a cross-sectional view of the isolator incorporating an electromagnetic shunt device according to the present invention.

Wherein: 1-a variable cross-section sheet beam; 2-a periodic structure; 3-a connector; 4-pressing the cover; 5-a base; 6-a base; 7-M5 bolt; 8-a spring washer; 9-M5 screw; 10-M6 bolt; 11-rubber; 12-a support column; 13-a piezoelectric material; 14-a power consuming circuit; 15-a spring; 16-a coil; 17-magnet.

Detailed Description

In order to make the technical problems, technical solutions and advantages of the present invention more apparent, the following detailed description is given with reference to the accompanying drawings and specific embodiments.

The invention provides a broadband vibration isolator with a periodic structure.

As shown in fig. 1, 2, 3 and 4, the vibration isolator comprises a variable cross-section thin sheet beam 1, a periodic structure 2, a connecting piece 3, a gland 4, a base 5 and a base 6, wherein the lower end surface of the base 5 is fixed on the base 6 through an M5 bolt 7, the upper end surface of the base 5 is connected with the tail part of the variable cross-section thin sheet beam 1 through an M5 bolt 7, the head part of the variable cross-section thin sheet beam 1 is connected with the lower end surface of the connecting piece 3 through an M5 screw 9, the inner cavity of the connecting piece 3 is used for placing a connecting part of an object needing to be isolated from vibration and is fixed through the gland 4 on the upper part of the connecting piece 3, and the gland 4 is connected with the connecting piece 3 through an M5 screw 9; through holes are reserved from the inner cavity of the connecting piece 3 to the lower end face of the connecting piece 3, and M6 bolts 10 penetrate through the through holes to connect the periodic structure 2 with the connecting piece 3; the periodic structure 2 is fixed on the base 6 through M5 bolts 7; the rubber 11 is filled in the periodic structure 2, and the periodic structure 2 is matched with the rubber 11 through a glue pouring process; a spring washer 8 is arranged at the joint of the M5 screw for preventing looseness; the M5 bolt joint is provided with a spring washer 8 for preventing looseness.

The widths of the upper end surfaces of the variable cross-section thin sheet beam 1 and the base 5 are the same, and the thickness and the length of the variable cross-section thin sheet beam 1 can be adjusted according to specific requirements. The cavity of the connecting piece 3 and the gland 4 can be adjusted according to the shape and size of the vibration isolation object as required, so that a reliable connection mode is guaranteed, and effective vibration isolation is carried out. The variable cross-section thin sheet beam 1 is made of materials with yield strength larger than 1600MPa and tensile strength larger than 1800 MPa; the base 5 is made of a material which is good in plasticity and easy to process.

The periodic structure 2 is a structure with a gap in the middle and integrally processed by 3D printing, and the periodic structure 2 is made of an alloy material with the tensile strength of more than 480MPa and the Mo content of 3%; the number of the 2 layers of the periodic structure is not less than 2; and each layer is divided into n parts by not less than 2 supporting columns 12, wherein n is not less than 2, the inside of each part is filled with rubber 11, the material selection of the rubber 11 can be adjusted according to specific working conditions, and the selection is based on indexes such as elastic modulus, Poisson's ratio, damping ratio and the like of the rubber 11.

The upper end surface of the base 5 and the lower end surface of the connecting piece 3 are processed into inclined planes, so that the M5 screw 9 can be conveniently used for being connected with the variable-section thin-sheet beam 1, and meanwhile, the angle of the inclined planes can be changed according to specific requirements.

In specific application, the variable cross-section thin sheet beam 1 is replaced by a constant cross-section thin sheet beam according to the vibration isolation requirement; the spring washer 8 is replaced by one of a stop washer and a self-locking nut for anti-loosening according to actual requirements.

The variable cross-section thin sheet beams 1 are arranged along the axial direction in an array mode, and at least 6 groups of installation positions are arranged.

As shown in fig. 5, a piezoelectric material 13 is disposed between the connecting member 3 and the periodic structure 2, and the piezoelectric material 13 is externally connected with an energy consumption circuit 14, so as to improve the damping characteristic of the system and realize active control.

As shown in fig. 6, a piezoelectric material 13 may be further adhered to the lower end surface of the variable cross-section sheet beam 1, and when the variable cross-section sheet beam 1 displaces, the piezoelectric material 13 is driven to displace, and the piezoelectric material 13 is externally connected to an energy consumption circuit 14.

As shown in fig. 7, in application, the periodic structure 2 may be replaced by a spring 15, a coil 16 is disposed outside the spring 15, the upper end of the coil 16 is connected to the lower end face of the connecting member 3, the lower end of the coil 16 is suspended, m sets of annular magnets 17 are disposed on the inner wall of the base 6, m is greater than or equal to 4, when the vibration isolator generates displacement in the working stage, the coil 16 makes relative motion with respect to the magnets 17, voltage is generated in the coil 16, and the coil 16 is externally connected with an energy consumption circuit 14, so that the damping characteristic of the system is improved, and active control is realized.

The periodic structure 2 is subjected to static pressure or the vibration isolation system is subjected to external environment disturbance, the time-varying section thin sheet beam 1 and the rubber 11 in the periodic structure 2 provide rigidity and damping, and the requirement of system broadband high-stability vibration isolation is met.

The following description is given with reference to specific examples.

According to the broadband vibration isolator with the periodic structure, the gland is of a two-piece annular structure, the connecting part of an object needing vibration isolation extends into the cavity of the connecting piece, and the gland and the connecting piece are fixed through the screw, so that the connection stability of the gland and the connecting piece is ensured. 6 groups of variable cross-section sheet beams are arranged, so 6 inclined planes are processed on the lower end face of the connecting piece so as to be connected with the heads of the variable cross-section sheet beams, and the inclination angles of the planes are determined according to specific vibration isolation working conditions; the tail part of the variable cross-section thin sheet beam is connected with the upper end surface of the base through a bolt, a through hole is reserved from the inner cavity of the connecting piece to the lower end surface of the connecting piece, and the bolt penetrates through the through hole to connect the periodic structure with the connecting piece; the bolt penetrates through a flange of the periodic structure to fixedly connect the periodic structure with the base, rubber is filled in the periodic structure, the periodic structure is matched with the rubber through a glue pouring process, and the whole base is of a circular structure.

The specific connection sequence is as follows: firstly, the variable cross-section thin sheet beam and the connecting piece are combined into a negative stiffness mechanism through screws, secondly, M6 bolts sequentially penetrate through the connecting piece and the periodic structure from top to bottom from the inner cavity of the connecting piece and are fixedly connected with each other, and the periodic structure is fixedly connected with the base through 6M 5 bolts. And then respectively connecting the variable cross-section thin sheet beam with the base, and fixedly connecting the base with the upper end surface of the base through M5 bolts. And finally, placing the connecting part of the object needing vibration isolation into the inner cavity of the connecting piece, covering the gland and fixing the connecting part through the M5 screw.

As shown in fig. 1, when the vibration isolation system is in an operating state, the vibration isolation system is in a balanced position due to the load gravity, i.e., the vertical gravity and the reaction force of the vibration isolator cancel each other out. The reaction force of the vibration isolator is provided by the deformation of the variable cross-section thin sheet beam and the periodic structure. Wherein the deformation amount is the deformation of the vibration isolator from the initial position to the equilibrium position after the static load is applied. When the vibration isolation system vibrates under the influence of the surrounding environment, the negative rigidity provided by the variable cross-section thin sheet beam and the band gap characteristic attached to the periodic structure can play a good role in inhibiting the vibration of the system.

In the scheme of the vibration isolator with the periodic structure of the piezoelectric material, as shown in fig. 5, the piezoelectric material is positioned between the connecting piece and the periodic structure, the piezoelectric material is externally connected with an energy consumption circuit, the damping characteristic of a system is improved, mechanical energy is converted into electric energy after the piezoelectric material is stressed, then the electric energy is consumed through components in a shunt circuit, the damping effect is achieved, and active control is achieved.

In addition to the above scheme containing piezoelectric material, the piezoelectric material can be adhered to the lower end face of the variable cross-section sheet beam, as shown in fig. 6, when the variable cross-section sheet beam displaces, the piezoelectric material is driven to displace, and the piezoelectric material is externally connected with an energy dissipation circuit, so that the damping characteristic of the system is improved, and active control is realized.

In the scheme of the periodic structure vibration isolator containing the magnet, as shown in fig. 7, the periodic structure is replaced by a spring, the upper end of the coil is connected with the lower end face of the connecting piece, and the lower end of the coil is suspended, so that the spring is ensured to be in the coil. The inner wall of the base is provided with n groups of annular magnets, n is larger than or equal to 4, when the vibration isolator generates displacement in the working stage, the coil makes relative motion relative to the magnets, voltage is generated in the coil according to the Faraday's law of electromagnetic induction, the coil is externally connected with an energy consumption circuit, the damping characteristic of the system is improved, and active control is achieved.

While the foregoing is directed to the preferred embodiment of the present invention, it will be understood by those skilled in the art that various changes and modifications may be made without departing from the spirit and scope of the invention as defined in the appended claims.

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