JP7321381B2 - Vibration suppression device - Google Patents

Description

The present disclosure relates to a vibration propagation suppression device.

Vibration propagation suppressing devices are used for the purpose of protecting precision equipment from vibrations and impacts applied from the outside when the precision equipment is installed. A vibration propagation suppressing device is generally a device that includes an elastic material or member, and is placed between a source of vibration or shock and the precision instrument to reduce vibration or shock to the precision instrument.

As one form of vibration propagation suppressing device, there is known one that utilizes a bandstop effect that blocks the propagation of vibration over a wide band by periodically arranging fluid mechanical elements that have inertia in addition to elasticity. This is inspired by a band-stop filter used for band elimination of electromagnetic waves, and by forming a periodic structure, it is possible to obtain a vibration propagation suppressing device that suppresses the propagation of elastic waves in a wide frequency band. The performance evaluation index of the vibration propagation suppressing device with such a periodic structure is the low frequency range, wide range, and low response of the frequency band in which the band stop effect appears. Therefore, in the prior art, the material of the fluid machine element is selected, the shape and periodic arrangement method are devised, and the improvement of these performances is pursued.

Patent Literature 1 discloses a uniaxial vibration propagation suppressing device in which fluid mechanical elements are periodically arranged in the vibration propagation direction. The hydromechanical element has two coaxially arranged volume chambers with an orifice having an intermediate mass therebetween and is filled with a fluid. In addition, the intermediate masses arranged in the fluid machine elements are connected to each other in the vibration propagation direction by means of elastic bodies. When an external load is input to the vibration propagation suppression device, the volume chamber of the fluid machine element expands and contracts in the axial direction, causing the internal fluid to flow through the orifice. At this time, since the fluid flows through the narrow orifice, the fluid is accelerated, producing a fluid mass effect in which the mass of the fluid mechanical element is increased when viewed from the load side. Due to the periodic arrangement of the fluid machine elements including this fluid mass effect, the vibration propagation suppressing device described in Patent Document 1 can stop while maintaining the external dimensions of the device compared to the vibration propagation suppressing device formed only by the conventional mechanical system. It is possible to achieve a lower band, a wider band, and a lower response.

WO2019/064669

In Patent Document 1, mechanical displacement is converted into fluid flow, and at that time, the fluid mass effect is amplified by causing the fluid to flow through a narrow orifice, realizing bandstop low-range, wide-range, and low responsiveness. are doing. In order to achieve this performance, the fluid machine element described in Patent Document 1 has a fluid-filled region formed by upper and lower volume chambers and an orifice as a closed space, and concentrates the flow of the fluid on the orifice. However, due to the requirement that the fluid-filled area be a closed space, it becomes necessary to combine independent parts such as a volume chamber, a flange, and an intermediate mass to close the space. They must be welded or bolted together as separate parts. As a result, the vibration propagation suppressing device described in Patent Literature 1 has a complicated structure, which poses a practical problem of increasing the number of parts.

The present disclosure has been made in view of the above, and an object thereof is to provide a vibration propagation suppressing device with a small number of parts.

In order to achieve the above object, a vibration propagation suppressing device according to the present disclosure includes a plurality of unit cells connected in series in the direction of vibration propagation between a support object and a base surface that undergoes forced displacement. each of the plurality of unit cells has a shape extending in a first direction that intersects the vibration propagation direction, partition walls forming a closed cross section, and a fluid filled in the space surrounded by the partition walls. The partition wall has a structure that causes a change in the area of the closed cross section with respect to a load applied in the direction of vibration propagation, at least one of both ends in the first direction is open, and the adjacent unit cells are , circumscribing each other with partition walls.

According to the present disclosure, a partition having a shape extending in a first direction that intersects the vibration propagation direction and forming a closed cross section, and a fluid filled in the space surrounded by the partition; It is possible to provide a vibration propagation suppressing device with a small number of points.

1 shows a vibration propagation suppressing device according to Embodiment 1. FIG. 1 is a perspective view showing a vibration propagation suppressing device according to Embodiment 1. FIG. The perspective view which shows the vibration propagation suppression apparatus which concerns on Embodiment 2. The perspective view which shows the vibration propagation suppression apparatus which concerns on Embodiment 3. FIG. 11 shows a vibration propagation suppressing device according to a third embodiment; The perspective view which shows the vibration propagation suppression apparatus which concerns on Embodiment 4. The figure which shows the vibration propagation suppression apparatus which concerns on Embodiment 4. The perspective view which shows the vibration propagation suppression apparatus which concerns on Embodiment 5. Sectional view showing a vibration propagation suppressing device according to Embodiment 6 The perspective view which shows the vibration propagation suppression apparatus which concerns on Embodiment 7. FIG. 11 is a top view showing a vibration propagation suppressing device according to Embodiment 7; XII-XII sectional view of FIG. XIII-XIII sectional view of FIG. The figure which shows the vibration propagation suppression apparatus which concerns on a modification

Hereinafter, a vibration propagation suppressing device according to embodiments for carrying out the present disclosure will be described with reference to the drawings.

(Embodiment 1)
As shown in FIG. 1, the vibration propagation suppressing device 100 according to the first embodiment includes a plurality of unit cells 10a to 10f that are connected in series in a vibration propagation direction 400. It is placed between a certain precision instrument 200 and a base surface 300 that undergoes forced displacement. The precision instrument 200 is supported by the vibration propagation suppression device 100 on the base surface 300 . The vibration propagation suppression device 100, the precision device 200 to be supported, and the base surface 300 constitute a vibration isolation system. Each of the plurality of unit cells 10a to 10f has a shape extending in a first direction intersecting the vibration propagation direction 400, as shown in FIG. 2, and partition walls forming a closed section 11 perpendicular to the first direction 20 and a fluid 30 filled in the space surrounded by the partition wall 20 . Note that the shape extending in the first direction is a shape in which a cross section taken along a plane perpendicular to the first direction has a closed closed cross section 11, and the cross section 12 of the partition wall 20 is elliptical, circular, or polygonal. including any shape including In Embodiment 1, a vibration propagation suppressing device 100 having an elliptical cross section 12 will be described. Also, the first direction intersecting the vibration propagation direction 400 will be described as the direction orthogonal to the vibration propagation direction 400, but the first direction may be any direction as long as it intersects the vibration propagation direction 400. is not limited to FIG. 1 shows a case where there are six unit cells 10, but if vibration propagation between the precision device 200 and the base surface 300 is suppressed, how many unit cells 10 are there? It's okay.

To facilitate understanding, mutually orthogonal xyz coordinates are set and referred to as appropriate. The vibration propagation direction 400 is set as the z direction, the first direction in which the unit cells 10a to 10f extend is set as the x direction, and the direction perpendicular to the x and z directions is set as the y direction.

Each of the unit cells 10a to 10f has a partition wall 20 having a uniform cross section 12 and an elliptical cylindrical shape extending in the x-direction, and a fluid 30 filled in the space surrounded by the partition wall 20. FIG. The vibration propagation suppressing device 100 is a periodic structure in which a plurality of unit cells 10a to 10f are arranged in series in a vibration propagation direction 400. As shown in FIG. The unit cells 10a-10f are connected to adjacent unit cells 10a-10f outside the barrier ribs 20. As shown in FIG. That is, the adjacent unit cells 10a to 10f are circumscribed by the partition walls 20. As shown in FIG. The unit cells 10b to 10e located in the middle stage of the periodic structure by arranging a plurality of them in series are coupled to two adjacent unit cells 10a to 10f. Also, the unit cell 10a in the first stage is coupled with one adjacent unit cell 10b, and the unit cell 10f in the last stage is coupled with one adjacent unit cell 10e.

The partition wall 20 is made of an elastic material containing metal or resin, and is flexible enough to change the area of the closed cross section 11 against a load applied in the vibration propagation direction 400 and return to its original shape when the load is removed. have The closed cross section 11 is a plane perpendicular to the x direction. The thickness of the partition 20 is uniform, and the cross-sectional shape of the partition 20 is uniform in the first direction. The partition wall 20 is open at least one end 21 of both ends in the x direction.

Fluid 30 is a fluid comprising water, silicone oil or superfluid helium. When an external force that causes in-plane deformation is applied to the unit cell 10 , the filled fluid 30 is pushed out in the out-of-plane direction 13 . The fluid 30 preferably has a high density in order to maximize the fluid mass effect, which will be described later, and to achieve a stop band with a low frequency range, a wide range, and a low response. In addition, when the fluid 30 flows in the out-of-plane direction 13, frictional attenuation occurs due to the relative speed with the partition wall 20, so the frictional attenuation is reduced and the flow of the fluid 30 is increased. is preferably water or a fluid with a viscosity lower than that of water, and preferably has a kinematic viscosity of 1 mm ² /s or less. Note that when liquid is used as the fluid 30 , the vibration propagation suppressing device 100 is preferably used in a place filled with the fluid 30 . By doing so, the fluid 30 pushed out in the out-of-plane direction 13 returns to the space surrounded by the partitions 20 when the load applied to the partitions 20 is removed. Further, when air is used as the fluid 30, the opening provided at the one end portion 21 of the partition wall 20 should be made small in order to increase the reaction force of the air.

Next, the operation of the vibration propagation suppressing device 100 described above will be described.

The vibration propagation suppressing device 100 is arranged in a load transmission path between the precision equipment 200 and the base surface 300 shown in FIG. Therefore, the effect that the load input to the first-stage unit cell 10a is not propagated to the final-stage unit cell 10f, and conversely, the effect that the load input to the final-stage unit cell 10f is not propagated to the first-stage unit cell 10a. have. When dynamic forced displacement in the vibration propagation direction 400 is applied to the first-stage unit cell 10a, the area of the closed cross section 11 changes due to the flexibility of the partition wall 20 of the first-stage unit cell 10a. , the fluid 30 is pushed in the out-of-plane direction 13 of the closed cross-section 11 . At this time, the elastic force due to the flexibility of the partition 20, the inertial force due to the accelerated motion of the partition 20 and the fluid 30 in the vibration propagation direction 400, and the inertial force due to the accelerated motion of the fluid 30 in the out-of-plane direction 13 are three. two forces arise as reaction forces to the forced displacement. Among these, the third effect of increasing the inertial force due to the acceleration motion of the fluid 30 in the out-of-plane direction 13 is called the fluid mass effect, and it is an effect that produces an inertial force greater than the mass actually possessed by the unit cells 10a to 10f. have.

A vibration propagation suppression device 100, which is a periodic structure including unit cells 10a to 10f having elasticity and inertia, has the effect of suppressing the propagation of elastic waves of specific frequencies. This effect is called the bandstop effect. A frequency band of elastic waves whose propagation is suppressed is called a stop band. The stop band is predicted and designed by deriving the dispersion relationship between the wave number κ (rad/m) and the frequency ω (rad/s) of the elastic wave propagating through the vibration propagation suppressing device 100 by theoretical analysis.

The vibration propagation suppressing device 100 having the above configuration is provided with a plurality of unit cells 10a to 10f each having a fluid 30 filled in a space surrounded by the partition wall 20, so that the load input to the first stage unit cell 10a is final. This has the effect of not propagating to the unit cell 10f of the stage, and conversely, the effect of not propagating the load input to the unit cell 10f of the final stage to the unit cell 10a of the first stage. As a result, the vibration propagation suppressing device 100 has the effect of preventing the vibration from propagating from the base surface 300 subjected to forced displacement to the precision equipment 200, which is the object to be supported. Further, the effect of expanding the inertial force due to the accelerated motion of the fluid 30 in the out-of-plane direction 13 is called the fluid mass effect, and has the effect of generating an inertial force greater than the mass actually possessed by the unit cells 10a to 10f. Since the unit cells 10a to 10f are periodic structures having elasticity and inertia, it is possible to obtain a bandstop effect that suppresses the propagation of elastic waves of specific frequencies. Since the unit cells 10a to 10f have a uniform cross-section 12, the periodic structure as a whole has a uniform cross-section and can be manufactured as an integral structure by wire electric discharge machining. In addition, the same periodic structure can be integrally formed using a three-dimensional printer. By forming the closed cross-section of the fluid-filled region, the effect of reducing the number of parts, downsizing and simplification of the device, and reducing the manufacturing cost can be obtained while obtaining the fluid mass effect.

On the other hand, in order to obtain the fluid mass effect by making the fluid-filled area a closed space, the closed space makes it impossible to access external processing tools, and the shape of the inside of the closed space is integrated. It is difficult to manufacture with For this reason, the closed space must be formed by manufacturing the volume chamber, the lid and the orifice as separate parts and welding or bolting them together. Therefore, the structure in which the fluid-filled region is a closed space has the problem that the number of parts is large, the structure is complicated, and the manufacturing process is time-consuming.

(Embodiment 2)
In the vibration propagation suppressing device 100 according to Embodiment 1, an example in which the partition wall 20 having a cylindrical shape with a uniform thickness has been described. Due to this structure, the bulkhead 20 is flexible as a whole, and the vibration propagation suppressing device 100 is likely to buckle against the load in the vibration propagation direction 400 . may become. The vibration propagation suppressing device 100 according to the second embodiment solves such an unstable state. Specifically, as shown in FIG. A bulkhead 20 having a wall 22 and a second rigid wall 23 and a first flexible wall 24 and a second flexible wall 25 connecting the first rigid wall 22 and the second rigid wall 23. .

The partition 20 has a first rigid wall 22, a second rigid wall 23, a first flexible wall 24 and a second flexible wall 25 connected to each other, and has a uniform cross section and extends in the x-direction. It has a hollow, flat cylindrical shape. A space surrounded by the partition wall 20 is filled with a fluid 30 . Also, FIG. 3 shows a case where there are six unit cells 10, but the number of unit cells 10 may be any number as long as vibration propagation is suppressed.

The first rigid wall 22 and the second rigid wall 23 are made of metal or resin, have flat plate shapes perpendicular to the z-direction, and are arranged parallel to each other. The thickness t1 of the first rigid wall 22 and the thickness t2 of the second rigid wall 23 are smaller than the distance d1 between the first rigid wall 22 and the second rigid wall 23 . The first rigid walls 22 of the unit cells 10a-10e are joined to the second rigid walls 23 of the adjacent unit cells 10b-10f. That is, the first rigid wall 22 of one of the adjacent unit cells 10a-10f circumscribes the second rigid wall 23 of the other unit cell 10b-10f. For example, the first rigid wall 22 of one unit cell 10a and the second rigid wall 23 of the other unit cell 10b circumscribe. Thereby, the unit cells 10a to 10e are stably connected to each other. The thickness t1 of the first rigid wall 22 may be the same as or different from the thickness t2 of the second rigid wall 23 .

The first flexible wall 24 and the second flexible wall 25 are made of an elastic body containing metal or resin, and have a curved surface shape convex outward with the space formed by the partition wall 20 inside. The first flexible wall 24 and the second flexible wall 25 have the flexibility to change the area of the closed cross-section 11 with respect to the applied load and return to the original shape when the load is removed. The thickness t3 of the first flexible wall 24 and the thickness t4 of the second flexible wall 25 are smaller than the thickness t1 of the first rigid wall 22 and the thickness t2 of the second rigid wall 23 . Therefore, even if the first flexible wall 24 and the second flexible wall 25 are made of the same metal or resin as the first rigid wall 22 and the second rigid wall 23, Flexible wall 24 and second flexible wall 25 may be flexible. The thickness t3 of the first flexible wall 24 and the thickness t4 of the second flexible wall 25 are preferably the same. The first flexible wall 24 connects one end 22a of the first rigid wall 22 and one end 23a of the second rigid wall 23, and the second flexible wall 25 connects the first rigid wall 23. The other end 22b of the wall 22 and the other end 23b of the second rigid wall 23 are connected. As a result, the first flexible wall 24 and the second flexible wall 25 are arranged apart from each other, so that the moment arm can be secured and the bending rigidity of the unit cells 10a to 10e is improved. Since the thickness t3 of the first flexible wall 24 and the thickness t4 of the second flexible wall 25 are the same, the first flexible wall 24 and the second flexible wall 25 are made uniform. to prevent the first rigid wall 22 and the second rigid wall 23 from tilting with respect to the z-direction. As a result, the bending rigidity of the vibration propagation suppressing device 100 as a whole is improved, buckling can be suppressed, and structural stability is improved.

(Embodiment 3)
In vibration propagation suppressing device 100 according to Embodiment 2, in order to improve structural stability, vibration propagation suppressing device 100 includes first rigid wall 22 and second rigid wall 23 arranged to face each other, and second rigid wall 22 and second rigid wall 23 facing each other. An example has been described with a partition 20 having a first flexible wall 24 and a second flexible wall 25 connecting one rigid wall 22 and a second rigid wall 23 . On the other hand, the vibration propagation suppressing device 100 according to Embodiment 3 follows the basic structure of the vibration propagation suppressing device 100 according to Embodiment 2, and is formed of partition walls 20 as shown in FIG. The structure is such that the area of the closed cross section 11 is made relatively small.

The partition 20 has a first rigid wall 22, a second rigid wall 23, a first flexible wall 24 and a second flexible wall 25 connected to each other, and has a uniform cross section and extends in the x-direction. It has a flat cylindrical shape. A space surrounded by the partition wall 20 is filled with a fluid 30 . The closed cross section 11 formed by the partition walls 20 has an H shape when viewed in the x direction. Also, FIG. 4 shows a case where there are six unit cells 10, but the number of unit cells 10 may be any number as long as vibration propagation is suppressed.

The first rigid wall 22 and the second rigid wall 23 are made of metal or resin, have a plate-like shape perpendicular to z, and are arranged parallel to each other. As shown in FIG. 5, the thickness t5 of the first rigid wall 22 and the thickness t6 of the second rigid wall 23 are greater than the distance d2 between the first rigid wall 22 and the second rigid wall 23. As shown in FIG. The thickness t5 of the first rigid wall 22 and the thickness t6 of the second rigid wall 23 are preferably at least twice the distance d2. By manufacturing the barrier ribs 20 by wire electric discharge machining, it is possible to easily obtain the barrier ribs 20 having a small distance d2 between the first rigid wall 22 and the second rigid wall 23 . As a result, the area of the closed cross section 11 shown in FIG. 4 formed by the partition wall 20 can be made relatively small. The thickness t5 of the first rigid wall 22 may be the same as or different from the thickness t6 of the second rigid wall 23 .

The first flexible wall 24 and the second flexible wall 25 are made of an elastic body containing metal or resin, and have a curved surface shape convex outward with the space formed by the partition wall 20 inside. The first flexible wall 24 and the second flexible wall 25 have the flexibility to change the area of the closed cross-section 11 with respect to the applied load and return to the original shape when the load is removed. The thickness t7 of the first flexible wall 24 and the thickness t8 of the second flexible wall 25 are smaller than the thickness t5 of the first rigid wall 22 and the thickness t6 of the second rigid wall 23, respectively. Therefore, even if the first flexible wall 24 and the second flexible wall 25 are made of the same metal or resin as the first rigid wall 22 and the second rigid wall 23, Flexible wall 24 and second flexible wall 25 may be flexible. The thickness t5 of the first flexible wall 24 and the thickness t6 of the second flexible wall 25 are preferably the same. The first flexible wall 24 connects one end 22a of the first rigid wall 22 and one end 23a of the second rigid wall 23, and the second flexible wall 25 connects the first rigid wall 23. The other end 22b of the wall 22 and the other end 23b of the second rigid wall 23 are connected.

Since the thickness t5 of the first rigid wall 22 and the thickness t6 of the second rigid wall 23 are larger than the distance d2 between the first rigid wall 22 and the second rigid wall 23, the closed cross section 11 shown in FIG. can be made relatively small. By making the area of the closed cross section 11 relatively small, an external force is applied to the vibration propagation suppressing device 100 in the vibration propagation direction 400, thereby increasing the acceleration that the fluid 30 receives in the x direction. This increases the inertial force of the fluid 30 and enhances the fluid mass effect. As a result, the stop band effect of the vibration propagation suppressing device 100 according to the third embodiment has a lower frequency range and a wider range than the vibration propagation suppressing device 100 according to the second embodiment. The unit cells 10a to 10f included in the vibration propagation suppressing device 100 according to the third embodiment have a uniform cross section 12, and the distance d2 between the first rigid wall 22 and the second rigid wall 23 is relative to each other. Since it is relatively small, it can be easily manufactured by wire electric discharge machining as a monolithic structure.

(Embodiment 4)
In vibration propagation suppressing device 100 according to Embodiment 3, the area of closed cross section 11 is relatively small, so that an external force is applied to vibration propagation suppressing device 100 in vibration propagation direction 400, causing fluid 30 to move in x direction. Examples have been described in which the directionally experienced acceleration is increased, resulting in a greater fluid mass effect. In this case, when an external force is applied to the unit cells 10a to 10f in the vibration propagation direction 400, the first flexible wall 24 and the second flexible wall 25 bulge outward. Thereby, the gap between the first flexible wall 24, the one end 22a of the first rigid wall 22 and the one end 23a of the second rigid wall 23, the second flexible wall 25, The gap between the other end 22b of the first rigid wall 22 and the other end 23b of the second rigid wall 23 widens, the amount of fluid 30 moving in the x direction is reduced, and a sufficient fluid mass effect is obtained. may be difficult to obtain.

In contrast, as shown in FIGS. 6 and 7, the vibration propagation suppressing device 100 according to the fourth embodiment includes the first flexible wall 24 and the second flexible wall 24 having convex curved surfaces facing each other. It has a flexible wall 25 . In this case, when an external force is applied to the unit cells 10a to 10f in the vibration propagation direction 400, the first flexible wall 24 and the second flexible wall 25 exhibit further necking deformation. Thereby, the gap between the first flexible wall 24, the one end 22a of the first rigid wall 22 and the one end 23a of the second rigid wall 23, the second flexible wall 25, The gap between the other end 22b of the first rigid wall 22 and the other end 23b of the second rigid wall 23 narrows, and deformation occurs to further reduce the area of the closed cross section 11 shown in FIG. As a result, the amount by which the fluid 30 moves in the x direction is relatively increased compared to the vibration propagation suppressing device 100 according to the third embodiment, and a sufficient fluid mass effect can be easily obtained. Further, the stop band of the vibration propagation suppressing device 100 according to the fourth embodiment can obtain a lower frequency range and a wider range than the vibration propagation suppressing device 100 according to the third embodiment. Further, in the vibration propagation suppressing device 100 according to Embodiment 4, similarly to the vibration propagation suppressing device 100 according to Embodiment 4, the partition walls 20 are manufactured by wire electric discharge machining, so that the first rigid wall 22 and the second rigid wall 22 are formed. It is possible to easily obtain the partition wall 20 with a small distance d2 from the two rigid walls 23.

(Embodiment 5)
In the vibration propagation suppressing device 100 according to Embodiments 1 to 4, the vibration propagation suppressing device 100, which is a periodic structure in which a plurality of unit cells 10a to 10f are arranged in one direction of the vibration propagation direction 400, has been described. As a result, a band-stop effect is realized in the vibration propagation direction 400 uniaxially. However, there are cases where a load is applied to the vibration propagation suppressing device 100 or the precision device 200, which is the object to be supported, along two axes in the z direction and the y direction, and it is desired to suppress the propagation of these along the two axes. In order to deal with such a case, the vibration propagation suppressing device 100 according to the fifth embodiment has a vibration propagation suppressing device which is a two-dimensional periodic structure in which the unit cells 10 are periodically arranged in two directions of two axes of the z-direction and the y-direction. A restraining device 100 is disclosed. As shown in FIG. 8, in addition to the vibration propagation direction 400, a vibration propagation direction 410 that is orthogonal is defined, and the unit cells 10 are also periodically arranged in this direction. As a result, the propagation of the two-dimensional load applied to the outside of the vibration propagation suppressing device 100, which is a two-dimensional periodic structure, is suppressed by the vibration propagation suppressing device 100, which is a two-dimensional periodic structure. It should be noted that the closed cross-section 11 of the unit cell 10 of the vibration propagation suppressing devices 100 according to Embodiments 3 and 4 may be reduced, and the first unit cell 10 having curved surfaces convex in the facing directions shown in Embodiment 4 may be used. The flexible wall 24 and the second flexible wall 25 are periodically arranged in the two directions of the z direction and the y direction, as shown in the vibration propagation suppressing device 100 according to the fifth embodiment. It may be applied to the vibration propagation suppressing device 100 which is a two-dimensional periodic structure. By doing so, it is effective in improving the structural stability and improving the band stop effect.

(Embodiment 6)
In the vibration propagation suppressing devices 100 according to Embodiments 1 to 5, when external loads are applied in the vibration propagation directions 400 and 410, the partition walls 20 of the unit cells 10 are deformed and the fluid 30 flows in the x direction. However, one end 21 of the unit cell 10 is not sealed, and the fluid 30 leaks to the outside when it is not used where it is filled with the fluid 30 . Therefore, the vibration propagation suppressing device 100 according to Embodiment 6 has flexible sealing walls 27 at the one end 21 and the other end 26 of the unit cell 10, as shown in FIG. As a result, the fluid 30 can be prevented from leaking to the outside, and the vibration propagation suppressing device 100 can be used even when it is not used in a place filled with the fluid 30 . Other configurations are similar to those of the vibration propagation suppressing device 100 according to the first embodiment.

Note, however, that the sealing wall 27 degrades the fluid mass effect in two respects. First, the sealing wall 27 has finite rigidity in the vibration propagation direction 400 , thereby suppressing in-plane deformation of the unit cell 10 due to an external load and reducing the discharge amount of the fluid 30 in the out-of-plane direction 13 . Furthermore, since the discharge direction is covered, the discharged fluid 30 has nowhere to go and is less likely to flow. If the sealing wall 27 does not have flexibility, the fluid mass effect becomes small, and the band stop effect of the vibration propagation suppressing device 100 cannot exhibit the expected performance.

Therefore, in the sixth embodiment, the sealing wall 27 is flexible in the out-of-plane direction 13 in addition to the vibration propagation direction 400 . The sealing wall 27 preferably has a higher flexibility than the partition wall 20 . As a result, the vibration propagation suppression device 100 or an external device due to the leakage of the fluid 30 is prevented from being adversely affected by the vibration propagation suppression device 100 or an external device. A propagation suppression device 100 is obtained. As a specific example of the sealing wall 27 having flexibility, a viscoelastic plug or a bellows structure extending in the out-of-plane direction 13 may be employed. By doing so, the vibration propagation suppressing device 100 of Embodiment 6 can prevent the fluid 30 from leaking to the outside. Alternatively, it is effective when there is a risk of causing a malfunction in an external device. Similarly, flexible sealing walls 27 may be provided at the one end 21 and the other end 26 of the unit cell 10 of the vibration propagation suppressing device 100 according to the second to fifth embodiments.

(Embodiment 7)
In the vibration propagation suppressing device 100 according to the sixth embodiment, sealing walls 27 are provided at the one end 21 and the other end 26 of each unit cell 10 in order to suppress leakage of the fluid 30 in the out-of-plane direction 13 . However, if the sealing wall 27 is provided in each unit cell 10, it is difficult to secure the flexibility of the sealing wall 27, and the change in the cross-sectional area of the closed cross-section 11 itself shown in FIG. flow is not sufficiently excited. As a result, the fluid mass effect becomes small, and the bandstop effect of the vibration propagation suppressing device 100 cannot sufficiently exhibit the expected performance.

Therefore, as shown in FIGS. 10 and 11, the vibration propagation suppressing device 100 according to Embodiment 7 includes an outer shell wall 40 that seals and houses the entire unit cell 10, and the fluid 30 is The space surrounded by the outer shell wall 40 is filled. This can prevent the fluid 30 from leaking to the outside of the outer shell wall 40 . Other configurations are the same as those of the vibration propagation suppressing device 100 according to the fourth embodiment.

As shown in FIG. 12, the outer shell wall 40 includes a first flange 41 connected to the unit cell 10a, a second flange 42 connected to the unit cell 10f, and a first flange 41 and a second flange 42 connected to the unit cell 10f. It has a side wall 43 that connects the flange 42 and is at least partially flexible, and the unit cells 10a to 10f are accommodated in an internal closed space 44. FIG. The first flange and the second flange are arranged across the plurality of unit cells 10a-10f in the vibration propagation direction 400. As shown in FIG. A space surrounded by the closed space 44 and the partition wall 20 is filled with the fluid 30 . The outer shell wall 40 has flexibility in at least a part of the side wall 43 so that the volume of the internal closed space 44 can be changed when a force is applied in the vibration propagation direction 400 , and the load on the vibration propagation suppressing device 100 is reduced. In contrast, the structure is such that displacement occurs in the internal unit cells 10a to 10f.

Side wall 43 may be made of a viscoelastic or metallic membrane and may have a bellows structure. Thereby, the outer shell wall 40 deforms when a force is applied in the direction of vibration propagation 400, and when the first flange 41 is fixed, the second flange 42 can move in the z-direction and the inner , the volume of the closed space 44 changes. Further, as shown in FIGS. 11 and 13, the sidewalls 43 are arranged with clearances in the x direction between the unit cells 10a to 10f. The distance d3 between the side wall 43 and the unit cells 10a to 10f is preferably of a size that allows the fluid 30 filled in the unit cells 10a to 10f to be discharged smoothly. On the other hand, as shown in FIGS. 11 and 12, the distance d4 between the side wall 43 and the unit cells 10a to 10f in the y direction is a size that prevents the unit cells 10a to 10f and the side wall 43 from interfering with each other. It is preferable that However, in the y direction, even if the distance d4 is 0, the fluid 30 filled in the unit cells 10a to 10f cannot be discharged. It is not always necessary to provide a clearance for

Since the outer shell wall 40 dynamically serves as a spring element parallel to the unit cells 10a to 10f, it must be designed flexibly without having excessive rigidity in the vibration propagation direction 400. FIG. However, when minimum strength is required for the vibration propagation suppressing device 100, it is important to design appropriately so that both the band stop effect and the strength are achieved.

Next, the operation of the vibration propagation suppressing device 100 having the above configuration will be described.

When an external load is applied to the vibration propagation suppressing device 100 in the vibration propagation direction 400, the load is transmitted through the first flange 41 or the second flange 42 to the internal unit cells 10a to 10f. As a result, the partition walls 20 of the respective unit cells 10a to 10f are crushed in-plane, and the fluid 30 is discharged at an accelerated rate in the x direction or -x direction, resulting in a fluid mass effect.

At this time, since clearances exist in the x direction between the side walls 43 and the unit cells 10a to 10f, the flow of the fluid 30 in the x direction is not hindered. As a result, the vibration propagation suppressing device 100 according to the seventh embodiment can suppress the leakage of the fluid 30 to the outside while obtaining the vibration propagation suppressing effect in which the stop band has a low-range property and a wide-range property due to the fluid mass effect. can. It should be noted that the vibration propagation suppressing device 100 according to the sixth embodiment is provided with the outer shell wall 40 that collectively seals and accommodates the entire unit cells 10 of the vibration propagation suppressing device 100 according to the fourth embodiment. However, the vibration propagation suppressing device 100 according to the seventh embodiment has the vibration propagation suppressing device 100 according to the first to third and fifth embodiments instead of the unit cell 10 of the vibration propagation suppressing device 100 according to the fourth embodiment. A unit cell 10 may be used.

(Modification)
In the above-described embodiments, examples were described in which the partition wall 20 was made of a flexible member or had the first flexible wall 24 and the second flexible wall 25 . The partition wall 20 may have any structure as long as it changes the area of the closed cross section 11 shown in FIG. 2 in response to the applied load. may have a structure that produces As an example, as shown in FIG. 14, the partition wall 20 includes a fixed wall 51 having a plate-like shape, a pair of sliding walls 53 arranged perpendicularly to the ends 52 of the fixed wall 51, and a plate-like wall. and is arranged between a pair of sliding walls 53 and moves in the z direction along the sliding walls 53, and an elastic wall 54 arranged between the fixed wall 51 and the moving wall 54. A body 55 may be provided. The fixed wall 51 and the moving wall 54 are arranged parallel to each other. The moving wall 54 is supported by an elastic body 55 to maintain a distance from the fixed wall 51 . The fluid 30 fills the space surrounded by the fixed wall 51 , the sliding wall 53 and the moving wall 54 . With this structure, when a load is applied, the elastic body 55 is elastically deformed and the moving wall 54 moves in the z direction, thereby pushing out the fluid 30 . As a result, it is possible to obtain a vibration propagation suppressing effect in which the stop band has both low-frequency and wide-range characteristics due to the fluid mass effect.

In the above-described embodiment, an example in which vibration propagation suppressing device 100 is arranged between precision instrument 200, which is an object to be supported, and base surface 300 that undergoes forced displacement has been described. The vibration propagation suppressing device 100 may be arranged between a vibration generating device having a mechanical configuration including a motor and the base surface 300 . A vibration generator includes a device having a mechanical configuration including a HDD (hard disk drive) or a motor. By doing so, there is an effect that the vibration generated by the vibration generator does not propagate to the base surface 300 . This has the effect of not propagating the vibration to other devices installed on the base surface 300 .

This disclosure is capable of various embodiments and modifications without departing from the broader spirit and scope of this disclosure. In addition, the embodiments described above are for explaining this disclosure, and do not limit the scope of this disclosure. That is, the scope of this disclosure is indicated by the claims rather than the embodiments. Various modifications made within the scope of the claims and within the scope of equivalent disclosure are considered to be within the scope of this disclosure.

10, 10a to 10f unit cell 11 closed section 12 section 13 out-of-plane direction 20 partition wall 21, 22a, 23a one end 22 first rigid wall 22b, 23b, 26 ... Other end 23... Second rigid wall 24... First flexible wall 25... Second flexible wall 27... Sealing wall 30... Fluid 40... Outer shell wall 41... First 42... Second flange 43... Side wall 44... Closed space 51... Fixed wall 52... End 53... Sliding wall 54... Moving wall 55... Elastic body 100... Vibration propagation suppression Apparatus 200... Precision instrument 300... Base surface 400, 410... Vibration propagation direction.

Claims (10)

A plurality of unit cells connected in series in the vibration propagation direction between the support object and the base surface that receives forced displacement,
Each of the plurality of unit cells has a shape extending in a first direction that intersects with the vibration propagation direction, and includes a partition wall forming a closed cross section, and a fluid filled in a space surrounded by the partition wall. have
The partition wall has a structure that changes the area of the closed cross section with respect to the load applied in the vibration propagation direction, and at least one of both ends in the first direction is open,
the adjacent unit cells are circumscribed by the partition walls;
Vibration propagation suppression device. The vibration propagation suppressing device according to claim 1, wherein the cross-sectional shape of the partition wall is uniform in the first direction. The partition includes a first rigid wall and a second rigid wall arranged to face each other, and a flexible first flexible wall connecting the first rigid wall and the second rigid wall. and a second flexible wall,
the first rigid wall of one of the adjacent unit cells and the second rigid wall of the other unit cell circumscribe;
3. The vibration propagation suppressing device according to claim 1 or 2. the distance between the first rigid wall and the second rigid wall is smaller than the thickness of the first rigid wall or the second rigid wall;
The vibration propagation suppressing device according to claim 3. each of the first flexible wall and the second flexible wall has a convex curved surface shape facing each other,
5. The vibration propagation suppression device according to claim 3 or 4. each of the plurality of unit cells are arranged side by side in a direction intersecting the vibration propagation direction and the first direction;
The vibration propagation suppressing device according to any one of claims 1 to 5. A plurality of unit cells connected in series in the vibration propagation direction between the support object and the base surface that receives forced displacement,
Each of the plurality of unit cells has a shape extending in a first direction that intersects with the vibration propagation direction, and includes a partition wall forming a closed cross section, and a fluid filled in a space surrounded by the partition wall. have
The partition wall has a structure that changes the area of the closed cross section with respect to the load applied in the direction of propagation of the vibration,
The adjacent unit cells are circumscribed by the partition walls and have flexible sealing walls at both ends in the first direction,
Vibration propagation suppression device. The vibration propagation suppressing device according to claim 7, wherein the sealing wall has higher flexibility than the partition wall. An outer shell wall that hermetically accommodates the plurality of unit cells,
The fluid is filled in a space surrounded by the outer shell wall,
The vibration propagation suppressing device according to any one of claims 1 to 6. The outer shell wall connects a first flange and a second flange arranged across the plurality of unit cells in the vibration propagation direction, and connects the first flange and the second flange, and at least a partially flexible sidewall;
The vibration propagation suppressing device according to claim 9.

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