阅读说明：本技术 一种低频宽带特性的准零刚度隔振器 (Quasi-zero stiffness vibration isolator with low-frequency broadband characteristic ) 是由 韦天山 李占龙 杨强 何霞 班顶顺 于 2019-10-17 设计创作，主要内容包括：本发明公开了一种低频宽带特性的准零刚度隔振器,包括负刚度机构和正刚度机构,负刚度机构包括上下两个固定磁环和中间的自由磁环,自由磁环安装在中轴(2)上,中轴(2)和正刚度机构连接,正刚度机构是人工肌肉结构。本发明创新设计了负刚度三磁环结构(固定上下磁环,内磁环固定于中轴随轴移动),正刚度利用搭载PAM的平台,易于控制；正负结构都可随被隔振物体适应性调节；工程实用性上有隔振器配套有上下连接机构,上端的球铰结构更拓宽了隔振器的使用领域和使用寿命。(The invention discloses a quasi-zero stiffness vibration isolator with low-frequency broadband characteristics, which comprises a negative stiffness mechanism and a positive stiffness mechanism, wherein the negative stiffness mechanism comprises an upper fixed magnetic ring, a lower fixed magnetic ring and a middle free magnetic ring, the free magnetic rings are arranged on a middle shaft (2), the middle shaft (2) is connected with the positive stiffness mechanism, and the positive stiffness mechanism is an artificial muscle structure. The invention innovatively designs a negative-rigidity three-magnet ring structure (an upper magnet ring and a lower magnet ring are fixed, an inner magnet ring is fixed on a middle shaft and moves along with the shaft), and positive rigidity is easily controlled by utilizing a platform carrying PAM; the positive and negative structures can be adaptively adjusted along with the vibration-isolated object; have the isolator to join in marriage the cover and have upper and lower coupling mechanism on the engineering practicality, the ball pivot structure of upper end has more widened the application range and the life of isolator.)

1. The utility model provides a quasi-zero rigidity isolator of low frequency broadband characteristic, includes negative stiffness mechanism and positive stiffness mechanism, its characterized in that: the negative stiffness mechanism comprises an upper fixed magnetic ring, a lower fixed magnetic ring and a middle free magnetic ring, the free magnetic rings are arranged on the middle shaft (2), the middle shaft (2) is connected with the positive stiffness mechanism, and the positive stiffness mechanism is an artificial muscle structure.

2. The quasi-zero stiffness vibration isolator with the low-frequency broadband characteristic according to claim 1, wherein: the artificial muscle structure comprises a plurality of artificial muscle units (11), an upper cover (12) and a mounting seat (14), wherein two ends of each artificial muscle unit (11) are hinged to the mounting seat (14) or the upper cover (12) respectively.

3. The quasi-zero stiffness vibration isolator with the low-frequency broadband characteristic according to claim 2, wherein: the total number of the artificial muscle units (11) is six, every two artificial muscle units form a group, two artificial muscle units (11) in each group are symmetrical and inclined at a certain angle, and the three groups are arranged in a central symmetry manner.

4. The quasi-zero stiffness vibration isolator with the low-frequency broadband characteristic according to claim 2, wherein: the two fixed magnetic rings of the negative stiffness mechanism are respectively an upper magnetic ring (5) and a lower magnetic ring (7), the two fixed magnetic rings are fixed on the inner wall of the inner shell (8), the free magnetic ring is an inner magnetic ring (6), and the upper magnetic ring (5), the inner magnetic ring (6) and the lower magnetic ring (7) are all permanent magnets.

5. The quasi-zero stiffness vibration isolator with low-frequency broadband characteristics according to claim 4, wherein: the upper half section of the middle shaft (2) is arranged in the linear bearing (3), the linear bearing (3) is arranged in the upper end cover (4), and the upper end cover (4), the outer shell (9) and the base (13) form an installation cavity of the whole vibration isolator.

6. The quasi-zero stiffness vibration isolator with the low-frequency broadband characteristic according to claim 5, wherein: the inner shell (8) is arranged in the outer shell (9), the inner wall of the inner shell (8) is provided with an upper ring groove and a lower ring groove for mounting and embedding the upper magnetic ring (5) and the lower magnetic ring (7), the mounting seat (14) is fixed on the base (13), and the outer diameter of the inner magnetic ring (6) is smaller than the inner diameters of the upper magnetic ring (5) and the lower magnetic ring (7).

7. The quasi-zero stiffness vibration isolator with low-frequency broadband characteristics according to claim 4, wherein: the magnetic pole direction of the inner magnetic ring (6) is along the axial direction or the radial direction, and the upper magnetic ring (5) and the lower magnetic ring (7) attract the inner magnetic ring (6).

8. The quasi-zero stiffness vibration isolator with low-frequency broadband characteristics according to claim 4, wherein: at least one negative stiffness mechanism is arranged, and the negative stiffness mechanisms are connected in series along the central shaft (2) when the number of the negative stiffness mechanisms is more than one.

9. The quasi-zero stiffness vibration isolator according to any one of claims 1 to 8, wherein: the top of the middle shaft (2) is provided with a bearing platform (1) through a spherical hinge (21).

10. The quasi-zero stiffness vibration isolator with the low-frequency broadband characteristic according to claim 9, wherein: a seat is arranged on the bearing platform (1).

Technical Field

The invention relates to a vibration isolator.

Background

The quasi-zero stiffness means that the negative stiffness mechanism and the positive stiffness mechanism are connected in series for use, and a vibration system comprising the negative stiffness mechanism has the advantages of low natural frequency, high bearing capacity, good vibration isolation effect and the like. At present, a spring mechanism and a magnetic force mechanism are generally used as a positive stiffness mechanism and a negative stiffness mechanism respectively, for example, a quasi-zero stiffness vibration isolator disclosed in chinese patent CN 109681573 a adopts an electromagnetic negative stiffness mechanism and a spring positive stiffness mechanism to form the quasi-stiffness mechanism, but the bearing capacity of a spring is weak, the deformation amplitude is large, and the human body experience as a vehicle seat is not good. And the negative stiffness mechanism it uses requires power to be applied.

Disclosure of Invention

The technical problem to be solved by the invention is as follows: aiming at the problem that the current quasi-zero stiffness vibration isolation mechanism is low in bearing capacity, the quasi-zero stiffness mechanism with high bearing capacity is provided, and can be used for seat vibration isolation of engineering vehicles.

The technical scheme of the invention is as follows: a quasi-zero stiffness vibration isolator comprises a negative stiffness mechanism and a positive stiffness mechanism, wherein the negative stiffness mechanism comprises an upper fixed magnetic ring, a lower fixed magnetic ring and a middle free magnetic ring, the free magnetic rings are arranged on a middle shaft, the middle shaft is connected with the positive stiffness mechanism, and the positive stiffness mechanism is an artificial muscle structure.

The artificial muscle structure comprises a plurality of artificial muscle units, an upper cover and a mounting seat, wherein two ends of each artificial muscle unit are hinged with the mounting seat or the upper cover respectively.

The total number of the artificial muscle units is six, every two artificial muscle units form a group, two artificial muscle units in each group are symmetrical and inclined at a certain angle, and the three groups are arranged in a central symmetry manner.

The two fixed magnetic rings of the negative stiffness mechanism are respectively an upper magnetic ring and a lower magnetic ring which are fixed on the inner wall of the inner shell, the free magnetic ring is an inner magnetic ring, and the upper magnetic ring, the inner magnetic ring and the lower magnetic ring are permanent magnets.

The upper half section of the middle shaft is arranged in a linear bearing, the linear bearing is arranged in an upper end cover, and the upper end cover, the outer shell and the base form an installation cavity of the whole vibration isolator.

The inner shell is arranged in the outer shell, an upper ring groove and a lower ring groove are formed in the inner wall of the inner shell and used for being embedded with an upper magnetic ring and a lower magnetic ring, the mounting seat is fixed on the base, and the outer diameter of the inner magnetic ring is smaller than the inner diameters of the upper magnetic ring and the lower magnetic ring.

The magnetic pole direction of the inner magnetic ring is along the axial direction or the radial direction, and the upper magnetic ring and the lower magnetic ring attract the inner magnetic ring.

At least one negative stiffness mechanism is arranged, and the negative stiffness mechanisms are connected in series along the central axis when the number of the negative stiffness mechanisms is more than one.

The top of the middle shaft is provided with a bearing platform through a spherical hinge.

And a seat is arranged on the bearing platform.

The invention has the beneficial effects that:

the positive stiffness mechanism adopts a multi-dimensional PAM supporting platform with the same air path, and comprises three groups of six PAMs, wherein two adjacent PAMs form an included angle of 60 degrees, two groups of PAMs form a plane, and the three groups form an included angle of 60 degrees with each other. The structure based on the multi-PAM can provide extremely strong positive rigidity and has enough bearing capacity; the multi-dimensional platform can be used for applying force to a heavy load in a balanced manner to a certain extent, so that the purpose of preventing unbalance loading is achieved. The regulation and control are accurate, the operation is simple, and the control is easy. The positive rigidity support for heavy load is more reliable. In actual operation, an initial position can be set, and then appropriate inflation amount is automatically given according to loads with different masses, so that the stability of the PAM supporting mechanism is maintained.

The negative stiffness mechanism is a three-magnet ring structure with brand new design. The inner magnetic ring is directly fixed at a certain position of the middle shaft, the middle shaft drives the fixed inner magnetic ring to move between the upper fixed magnetic ring and the lower fixed magnetic ring along with the change of load, the specific magnetizing mode has two choices, and the most suitable magnetizing direction can be selected according to the arrangement and the size of different three magnetic rings, so that more stable negative rigidity characteristic is brought. Full reference is made here to the actual case of the magnet ring magnetizing method and the magnetic pole arrangement. The variable load-bearing negative stiffness mechanism can be changed according to load, a plurality of negative stiffness mechanisms can be accumulated, and the negative stiffness performance is enhanced under the same magnetizing condition. The inner magnetic ring directly generates negative rigidity along with the movement of the middle shaft between the upper magnetic ring and the lower magnetic ring.

In conclusion, the negative stiffness can be enhanced by the accumulation of the magnetic rings, and the positive stiffness multi-dimensional PAM platform is good in heavy-load supporting performance. The whole matching can realize low-frequency vibration isolation. The two advantages of heavy-load support and low-frequency vibration isolation are integrated. No matter from three magnetic ring principles or structural, no matter from the flexibility ratio of structure or the magnetic ring arrange the diversity on, my patent structure is clear, the simple operation, and the innovation advantage is obvious. A negative-rigidity three-magnet ring structure (an upper magnet ring and a lower magnet ring are fixed, and an inner magnet ring is fixed on a middle shaft and moves along with a shaft) is created, so that the magnetic pole arrangement and the magnetizing direction of the magnet rings are created; the positive rigidity utilizes a platform carrying PAM, and the control is easy; the positive and negative structures can be adaptively adjusted along with the vibration-isolated object; have the isolator to join in marriage the cover and have upper and lower coupling mechanism on the engineering practicality, the ball pivot structure of upper end has more widened the application range and the life of isolator.

Description of the drawings:

fig. 1 is a schematic view of the overall structure of the present invention.

Fig. 2 is a perspective view of the invention in half section.

FIG. 3 is a schematic diagram of a series of negative stiffness mechanisms.

Fig. 4 and 5 are schematic views of a magnetic pole arrangement, respectively.

Fig. 6 is a schematic structural view of a positive stiffness mechanism.

Fig. 7 is a schematic view of the installation structure of the pneumatic artificial muscle.

Detailed Description