JPH10213178A - Passive vibration damping device and vibration damping method - Google Patents

Abstract

PROBLEM TO BE SOLVED: To support a supported body flexibly to vibrational disturbance, effectively insulate transmission of vibrational input and support the supported body relatively with high rigidity against vibrational input or exciting force of excessive amplitude or action of steady acceleration. SOLUTION: A vibration damping device 1 is provided with upper and lower vibration damping units 2, 3 provided with housings 12 that can store a fluid, and a center shaft 5 for connecting the vibration damping units 2, 3 spaced by the specified distance, to eath other. Elastic films 4 of the upper and lower vibration damping units 2, 3 close fluid filled areas 8 in the housings 12. Fittings 6 disposed at both end parts of the center shaft 5 are connected so as to be integrally displaceable to the center areas of the elastic films 4, and the elastic films 4 generate responsive vibration in an out-of-plane direction to vibrational disturbance transmitted through the center shaft 5.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a passive vibration damping device and a vibration damping method, and more particularly, to an in-flight environment of a spacecraft, a flying object, a high-speed elevating device, or the like that fluctuates gravity over a relatively wide range. As in a low gravity environment such as a microgravity environment or a zero gravity environment, and under a special environment where gravity changes to a high gravity environment where a steady acceleration or a high gravity acceleration acts,
The present invention relates to a passive vibration damping device and a vibration damping method that can effectively insulate vibration input or excitation force of a whole vibration system including a supported body and a support body.

[0002]

2. Description of the Related Art Vibrations including a support and a supported member are interposed in a stress transmission path between a support such as a base or a base and a supported member such as a precision instrument disposed on the support. 2. Description of the Related Art Vibration damping devices such as vibration isolation devices or seismic isolation devices for achieving vibration isolation of a system are widely used in practice. The vibration damping device supports a supported device such as a precision device on a support to which vibration of the vibration source or the vibration generation source is input so as to be able to isolate the vibration, or supports a vibration device to be a vibration generation source. It is supported so as to be able to isolate vibration. For example,
In an engine mount device interposed between a vehicle engine that constitutes a vibration source and a vehicle body chassis that supports the engine, a liquid is injected into an elastic body such as rubber in order to adapt to a wide range of vibration frequency characteristics of the engine. A liquid-filled engine mount device or the like having a configuration in which the liquid crystal is sealed is known (see Japanese Utility Model Laid-Open No. 3-52442).

As a vibration control method of this type of vibration control device, a so-called passive control method (passive vibration control method), an active control method (active vibration control method) and a semi-active control method (quasi-active vibration control method) are used. Is generally known. The passive control method (passive vibration suppression method) considers the general characteristics of vibration disturbance, and preliminarily sets the structural characteristics and vibration of an elastic body such as a spring so as to avoid the resonance phenomenon of a supported body such as anti-vibration equipment. 2. Description of the Related Art It is known as a vibration control method in which a vibration control device whose damping characteristics and the like are adjusted is interposed between a vibration source and a stationary body or a structure. On the other hand, the active control method (active vibration suppression method) generally detects a change in vibration disturbance or vibration of a vibration source by vibration detecting means such as a vibration sensor, and externally detects the change based on a control signal of the vibration detecting means. The control force is applied to the
This is a vibration damping method in which a variable input is made to a stationary body or a vibration source, thereby actively canceling the excitation force and reducing the vibration response of the supported body or the stationary body. In addition, the semi-active control method (semi-active vibration suppression method) generally has a rigidity, a vibration damping characteristic, or a mass of a supported or stationary body corresponding to a situation or state of vibration detected by the vibration detecting means. This is a vibration suppression technique that suppresses the transmission of vibration while quickly changing the conditions. Vibration suppression devices to which the passive control method (passive vibration suppression method) is applied include peripheral devices and animals in various basic researches or experiments in a microgravity environment or a zero gravity environment (hereinafter, simply referred to as “microgravity environment”). It is used as vibration isolation means for reducing regular or irregular vibration disturbances caused by a human body or the like as a vibration source. This type of vibration damping device includes various experimental devices such as a measuring device or an image processing device, and a vibration insulator interposed between the experimental device mounting table or the support table. It is composed of a relatively low-rigidity material or component that flexibly supports the experimental equipment, and functions to insulate the vibration disturbance input to the experimental equipment via the experimental equipment mounting base or the like.

[0004]

In such a conventional vibration damping device, the rigidity and the like of a vibration insulator adapted in advance to the vibration characteristics are controlled against a vibration disturbance in which various factors such as frequency and amplitude are relatively stable. By setting as desired, it can function to some extent effectively. However, the actual vibration disturbance in the various researches and experiments under the microgravity environment tends to be unstable in both frequency and amplitude. For example, in the microgravity environment, the amplitude is transiently excessive due to unstable vibration disturbance. For example, vibration characteristics may be difficult to predict in advance, for example, may occur. Therefore, it is practically extremely difficult to design a vibration insulator having an optimum vibration insulation performance. In addition, various research and experiments under the above microgravity environment are performed at the drop test facility,
It is carried out in an experimental facility such as an aircraft, a small rocket or a space shuttle. The gravitational environment in this type of experimental facility is a variable gravitational environment showing a wide range of gravitational fluctuations from zero gravity or a microgravity value of about 0.01 G to a relatively large gravitational value of about 2 G. For this reason, it is necessary to design a vibration insulator that exhibits vibration insulation performance that can adapt to a wide range of gravity fluctuations. In particular, when an excessive amplitude of vibration or exciting force acts on the vibration system including the experimental equipment and the experimental equipment mounting base, or when relatively excessive gravity including a steady acceleration acts on the entire vibration system, As a result, the displacement or deformation of the flexible vibration insulator, which is generally designed to have low rigidity to adapt to the microgravity environment, is transiently amplified. A situation can arise where abutment or abutment occurs. Therefore, there is a demand for the development of a vibration damping device having a novel configuration capable of supporting a supported member in such a manner that vibrations can be insulated as desired under such a variable gravity environment.

The present invention has been made in view of the above problems, and has as its object to maintain a flexible and flexible support for stable vibration disturbance and effectively insulate transmission of vibration input. When the vibration input or the excitation force having an excessive amplitude acts on the vibration system, or when the steady acceleration acts on the entire vibration system, the supported body can be supported with relatively high rigidity. An object of the present invention is to provide a passive vibration damping device and a vibration damping method. The present invention also provides a good experimental environment that effectively isolates vibration disturbance input to a vibration system including an experimental device or an experimental device in various experiments utilizing the specialty of the microgravity environment, and is hardly affected by the vibration disturbance. It is an object of the present invention to provide a passive vibration damping device and a vibration damping method that can realize the above. The present invention can also be used as desired in vibration systems in which vibration inputs or excitation forces of unpredictable vibration characteristics can act due to sudden and wide variations in the surrounding environment or atmosphere, and , Passive vibration damping device that can effectively avoid the occurrence of rapid vibration amplification or resonance phenomenon of a vibration system including a vibration damping device and can exhibit effective vibration damping performance against amplitude fluctuation of a wide range of vibration systems And a vibration damping method.

[0006]

SUMMARY OF THE INVENTION In order to achieve the above object, the present invention relates to a support for forming a vibration system in order to regulate the transmission of vibration of the vibration system due to vibration disturbance acting on the vibration system. A passive vibration damping device including a flexible vibration responsive member interposed between a member and a supported member and having a vibration damping function, wherein the first vibration damping unit and the second vibration damping unit each including a housing; A shaft member interconnecting the first and second vibration damping units at a predetermined interval, wherein each of the first and second vibration damping units has an elastic film made of a flexible material, Both end portions of the shaft member are connected to the respective elastic films of the first and second vibration damping units so as to be integrally displaceable with the elastic film, and the elastic film is connected to the vibration disturbance transmitted through the shaft member. Causes out-of-plane response vibration to
The vibration disturbance is attenuated by a vibration response effect due to the elastic displacement of the elastic film, and the elastic film transiently receives an excessive amplitude vibration input to the elastic film via the shaft member. The elastic restoring force of the elastic film, which increases in accordance with the out-of-plane deformation of the elastic film, resists an increase in internal stress acting on the elastic film, and prevents the amplification of vibration of the shaft member by the out-of-plane rigidity of the elastic film. A passive vibration damping device is provided. According to the configuration of the present invention,
Both end portions of the shaft member are connected to the elastic films of the first and second vibration damping units at predetermined intervals, and interconnect the support and the supported member via the elastic films so as to transmit stress. In a low-gravity environment such as a microgravity environment, the vibration damping device supports the supported member on the support by the out-of-plane rigidity of the elastic film, and transmits vibration that can be transmitted between the supported member and the support to the elastic film. Damped by the vibration response characteristics of

According to the present invention, in the passive vibration damping device having the above-mentioned structure, the housing has an internal structure forming a fluid accommodating region capable of accommodating a fluid, and the elastic film closes the fluid accommodating region. And a vibration response function based on the viscosity of a fluid sealed in the fluid storage area and a vibration response function due to an elastic displacement of the elastic film, wherein the elastic disturbance attenuates the vibration disturbance. A vibration device is provided. According to such a configuration, the shaft member interconnects the support and the supported body via the elastic film and the sealed fluid so that stress can be transmitted, and the vibration damping device operates in a low gravity environment with the supported body and the support body. Is attenuated by the vibration response characteristics of the elastic film and the sealed fluid.

According to another aspect of the present invention, there is further provided a passive vibration damping device having the above-mentioned structure, wherein the housing has an internal hollow region which is in communication with an external atmosphere or an external gas region.
A passive vibration damping device is provided, wherein the constituent surface of the elastic film faces the hollow region.

According to the present invention, in the passive vibration damping device having the above-mentioned structure, the shaft member extends through the elastic film into an internal region of the housing, and the extending portion of the shaft member is A seat portion displaceable integrally with the shaft member and the elastic film; the housing inner region includes a bearing surface on which the seat portion can be elastically seated; and the bearing surface includes the housing inner region. The present invention provides a passive vibration damping device characterized by being formed of an elastic material disposed on a bottom wall of the passive vibration damping device. According to the above configuration of the present invention, the upper and lower vibration damping units approach each other due to deformation of the elastic film in a high gravity environment such as on the ground, and the seating portion of the shaft member is supported on the bearing surface in the area inside the housing. As a result, the stress in the axial direction of the shaft member is directly transmitted to the supported member and the support member via the elastic material. Therefore, the supported body is supported on the support substantially by the supporting force of the shaft member. On the other hand, the upper and lower vibration damping units are separated from each other due to deformation of the elastic film in a low gravity environment such as outer space, and the seating portion of the shaft member is separated from the bearing surface in the area inside the housing. As a result, the axial stress of the shaft member is transmitted to the supported member and the support member through the out-of-plane rigidity of the elastic film. Therefore, the vibration damping device supports the supported member on the support by the out-of-plane rigidity of the elastic film in a low gravity environment, and transmits the vibration transmitted between the supported member and the support to the vibration response of the elastic film. Attenuated by characteristics.

[0010] The present invention further provides a vibration damping device in which a flexible member is interposed between a supported member and a supporting member constituting a vibration system on which a vibration disturbance acts to attenuate the vibration of the vibration system due to the vibration disturbance. In the method, the vibration system is disposed in an environment with gravity fluctuation, a plurality of flexible membrane members spaced at a predetermined interval, and is oriented in a direction intersecting a constituent surface of the membrane member, and The supported member is placed on the support member through a shaft member interconnected so as to transmit a stress, and the supported member is supported by the out-of-plane rigidity of the membrane member under a low gravity environment. A vibration damping method is provided, wherein the vibration transmitted between the supported member and the support member is attenuated by a vibration response characteristic of the membrane member. According to the above configuration of the present invention, for example, in various experiments utilizing the specialty of the microgravity environment, the vibration disturbance input to the vibration system including the supported member such as an experimental apparatus or an experimental device causes the vibration response of the membrane member. The vibration is attenuated by the characteristics, the vibration transmission path between the supported member and the support member is effectively insulated, and a favorable experimental environment that is not easily affected by vibration disturbance can be realized in a low gravity environment.

[0011] The vibration damping method according to the present invention according to the above structure further comprises the step of deforming the membrane member under a high gravity environment.
The shaft member is displaced to a directly connected position where the axial stress of the shaft member is directly transmitted to the supported member and / or the support member, and the supported member is substantially moved by the support force of the shaft member. Supported on a support, and in a low-gravity environment, the shaft member is displaced to a separated position for transmitting an axial stress of the shaft member to the film member by an elastic restoring force of the film member; Releasing a direct stress transmission path between the substrate and the supported member and / or the support member, interconnecting the supported member and the support member through the membrane member so as to transmit the stress, and A vibration damping method is provided, wherein a body is substantially supported on the support by the membrane member. According to the above configuration, the shaft member is displaced to the directly connected position under a high gravity environment such as on the ground, and directly transmits the axial stress of the shaft member to the supported member and the support member via the soft member or the like. The supporting member is supported on the supporting member substantially by the supporting force of the shaft member.On the other hand, in a low gravity environment such as outer space, the shaft member is displaced to the separated position by the elastic restoring force of the membrane member, The supported member and the support member are interconnected via the membrane member so that stress can be transmitted, and the supported member is substantially supported on the support member by the membrane member. Therefore, in a vibration system in which a vibration input or an excitation force having unpredictable vibration characteristics can act due to sudden and wide fluctuations in the surrounding environment or surrounding atmosphere, the vibration control device includes a vibration system including the vibration control device. It is possible to reliably avoid the occurrence of rapid vibration amplification or resonance phenomenon, and to exhibit effective vibration damping performance against amplitude fluctuations of a wide range of vibration systems.

[0012] The present invention further provides the vibration damping method having the above-mentioned structure, wherein the supported member is interposed through the flexible membrane member and the shaft member, and a sealed fluid entirely in contact with the constituent surface of the membrane member. Is mounted on the support. According to such a configuration, the shaft member
The support and the supported body are interconnected so as to transmit stress through the membrane member and the sealing fluid. Therefore, the vibration damping device attenuates the vibration that can be transmitted between the supported member and the support member in a low gravity environment by the vibration response characteristics of the membrane member and the sealed fluid, and transmits the vibration between the supported member and the support member. Suppress.

[0013]

According to a preferred embodiment of the present invention, the distance between the housings constituting the first and second vibration damping units is different from the distance between the seating surface of the seating portion and the bearing surface. The distance is set to more than twice the distance. Therefore, each housing of the first and second vibration suppression units secures a predetermined separation distance at a position directly connected to the shaft member. More preferably, the axis of the shaft member is oriented so as to be substantially perpendicular to the plane of construction of the elastic membrane, and the amplitude of the elastic membrane occurs in a direction out of the plane perpendicular to the plane of construction of the elastic membrane. Preferably, the structure or form of the first and second vibration damping units is formed symmetrically with respect to the center plane of the vibration damping device. In a preferred embodiment of the present invention, the fluid is a liquid having a predetermined viscosity, and is formed in the housing and sealed in the fluid storage area closed by the elastic film, and is provided in the fluid storage area. The entire surface of the elastic membrane facing the region is in contact. More preferably, the elastic membrane has a generally circular contour, the center of the elastic membrane substantially coincides with the central axis of the shaft member. Preferably, the opening through which the reduced diameter portion formed at the end of the shaft member can be inserted,
It is formed at the center of the elastic membrane. According to another preferred embodiment of the present invention, the hollow region is interconnected with an external atmosphere or an external gas region through orifice means, and the fluid containing region is connected with the external atmosphere or an external gas region through the orifice means. Intercommunicate with the area. Preferably, the sealed fluid is made of a gas that can flow through the orifice means, flows through the orifice means in accordance with the volume fluctuation of the fluid storage area, and thus the sealed fluid passing through the orifice means is a gas of the orifice means. Subject to friction.

According to a preferred embodiment of the present invention, the bearing surface defines a recess in the bottom region of the interior region of the housing in which the seating portion can be at least partially received. More preferably, the seating portion includes an enlarged member fixed to each end of the shaft member, and an outer contour of the enlarged member is formed in a form substantially complementary to the concave form of the bearing surface, The seating surface of the seating portion is formed on the bottom surface and / or the side surface of the expanding member, and the bearing surface is formed on the bottom wall surface and / or the side wall surface of the recess. Preferably, the expanding member is a fluid that interconnects a first intermediate region or a fluid region between the elastic membrane and the expanding member and a second intermediate region or the fluid region between the bearing surface and the seating surface. A communication path is provided. According to a further preferred embodiment of the present invention, an elastically deformable soft member is interposed between the shaft member and the supported member or the support member. The soft member elastically supports the end portion of the shaft member so that stress can be transmitted at the directly connected position of the shaft member, and secures the separated state of the membrane members, and at the separated position of the shaft member. The shaft member is separated from an end of the shaft member so as to release a direct stress transmission path between the shaft member and the supported member and / or the support member.

[0015] Preferably, the elastic restoring force of the membrane member has a non-linear elastic body characteristic, and increases relatively sharply with an increase in the amount of displacement of the membrane member. More preferably, the pressure fluctuation of the sealed fluid is compensated by the elastic deformation of the membrane member.
According to a preferred embodiment of the present invention, silicone oil is used as the sealed fluid, and silicon gel is used as the soft member. According to another preferred embodiment of the present invention, as the gas, air in an external atmosphere or an inert gas is employed. In a preferred embodiment of the present invention, the housing defines a fluid accommodating region capable of accommodating a fluid, the elastic membrane or the membrane member closes the fluid accommodating region, and the vibration suppression device further includes a fluid accommodating device. Orifice means are provided for interconnecting the region and the housing exterior or external fluid region in fluid communication. The fluid containing area is interconnected with the outside world or an outside fluid area via orifice means;
Fluid flows through the orifice means in response to volume fluctuations in the fluid storage area. The frictional force of the fluid generated when passing through the orifice means acts on the elastic film as a vibration damping force of the vibration system. Thus, the elastic membrane attenuates vibration disturbance by vibrating response action due to the viscosity of the fluid sealed in the fluid storage area and vibrating response action due to the elastic displacement of the elastic membrane.

[0016]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS Hereinafter, a vibration damping device according to a first embodiment of the present invention will be described in detail with reference to the accompanying drawings. FIG.
FIG. 2 is a perspective view showing an overall configuration of the vibration damping device according to the first embodiment of the present invention, and FIG. 2 is a perspective view of the vibration damping device shown in FIG. It is an exploded perspective view. In addition, in order to simplify the drawing and facilitate understanding of the entire configuration of the vibration damping device, the fluid filling means (fluid filling tool and discharging tool) shown in FIG. 3 is not shown in FIGS. 1 and 2. is there. The vibration damping device 1 includes an upper vibration damping unit 2 and a lower vibration damping unit 3 that can be relatively displaced, and a cylindrical central shaft 5 that interconnects the upper vibration damping units 2 and the lower vibration damping units 3. Upper and lower vibration suppression units 2,
Numerals 3 are arranged vertically above and below the center axis of the vibration damping device 1 and have a form and structure that is plane-symmetric (plane-symmetric) with respect to the central horizontal plane of the vibration damping apparatus 1 and face each other. The upper and lower vibration damping units 2 and 3 each have a horizontal base or base plate 1 having a substantially square planar shape.
0 is provided. A cylindrical housing 12 extends in the center axis direction from the base 10 toward the other vibration damping unit, and a horizontal elastic membrane 4 having a circular flat shape is disposed at a free end portion of the housing 12. Circular through holes 11 are formed in each corner region of the horizontal base 10, and each through hole 11 has an inner diameter through which a locking tool such as a locking bolt or a fixing bolt or a fixing tool (not shown) can be inserted. . The locking device or the fixing device is fastened to an experimental device support base S (FIG. 7) that supports the vibration damping device 1 or an experimental device E (FIG. 7) to be supported by the vibration damping device 1. Further, an annular film member holding portion 13 for holding the elastic film 4 in the housing 12 is formed at the lower end (the vibration damping unit 2) or the upper end (the vibration damping unit 3) of the housing 12. The base 10, the housing 12, and the holding portion 13 that constitute each of the vibration damping units 2 and 3 are aligned around the central axis of the vibration damping device 1. The central axis 5 extends vertically along the central axis of the upper and lower vibration damping units 2, 3, and the upper end and the lower end of the central axis 5 penetrate the elastic film 4. , 3 extend into the housing 12.

FIG. 3 is a longitudinal sectional view showing the entire structure of the vibration damping device shown in FIGS. 1 and 2, and includes a partially enlarged view of the elastic membrane supporting structure ("A" portion). FIG. 4 is a sectional view of the vibration damping device 1 taken along the line VI-VI in FIG.
6 is a cross-sectional view of the vibration damping device 1 along the line VV in FIG. 3, and FIG. 6 is a cross-sectional view of the vibration damping device 1 along the line IV-IV in FIG. As shown in FIG. 3, the housing 12 of each of the vibration damping units 2 and 3 forms a hollow area 8 in which the fitting 6 and the fitting bush 7 can be housed inside the cylindrical wall body 15. The hollow region 8 is defined by a bottom wall 14 formed by the base 10, an inner peripheral wall surface of the cylindrical wall 15, and the elastic film 4 having a stretched film structure in which the outer peripheral region is fixed by the holding portion 13. Thus, a fluid-tight region capable of enclosing a fluid adjusted to a predetermined pressure is formed. As shown in a partially enlarged view of FIG. 3 (FIG. 3: an enlarged view of “A” portion), the outer peripheral edge of the elastic membrane 4 having a generally circular outer contour is formed by a membrane member holding portion 13 and a cylindrical wall body. 15 is inserted. Ring holding grooves 18 are formed in the distal end portion of the cylindrical wall body 15 and the base end surface of the membrane member holding portion 13, respectively, and the O-ring 42 is inserted into each ring holding groove 18. An annular outer spacer 41 abutting on the O-ring 42 is arranged in a pair with the outer peripheral edge of the elastic film 4, and the outer spacer 41 sandwiches the outer peripheral portion of the elastic film 4. A screw portion 16 formed on the inner peripheral wall of the membrane member holding portion 13 is screwed with a screw portion 17 formed on the outer peripheral surface of the distal end portion of the cylindrical wall body 15. The outer peripheral edge portion of the elastic film 4 is fixed to the O-ring 42 by fastening the screw portions 16 and 17.
And, it is sandwiched between the membrane member holding portion 13 and the cylindrical wall body 15 via the outer spacer 41. Thus, the outer peripheral region of the elastic membrane 4 is integrally restrained by the outer peripheral region of the end of the housing 12 and hermetically seals the hollow region 8 in a gas-tight and liquid-tight state.

The elastic film 4 is made of synthetic rubber, natural rubber, elastomer, a mixed material of synthetic rubber and natural rubber, a synthetic resin such as a soft vinyl chloride resin, or an elastic soft material such as a mixed material of a rubber material and a resin material. It is formed of a circular thin plate-like molded product obtained by molding a material as a membrane material. If desired, a reinforcing material such as short fibers or a mixed material may be contained in the elastic soft material. Due to the out-of-plane geometrical rigidity of the rubber-based sheet or the soft resin-based sheet stretched in the end region of the housing 12, the elastic film 4 is used for the vibration damping units 2, 3 and the center shaft 5, especially in a microgravity environment. Responds according to the vibration amplitude and exhibits a dynamic behavior that absorbs vibration disturbance. Preferably, the thickness of the elastic film 4 is set as thin as possible within a manufacturable range and an allowable strength range. Preferably, the thickness or thickness of the elastic film 4 is designed to be 0.1 mm to several mm, and more preferably, 0.1 mm to about 2 to 3 mm. The central shaft 5 has a cylindrical shaft portion 50 constituting a main body portion and relatively small diameter reduced portions 51 protruding from both ends of the shaft portion 50, while the fitting 6 has a reduced diameter. Female screw part 6 that can be screwed with the male screw of part 51
0 is provided. The enlarged diameter portions 52 formed at both ends of the shaft portion 50 are
The reduced diameter portion 51 that comes into contact with the surface of the elastic film 4 and protrudes from the enlarged diameter portion 52 penetrates the center circular hole 40 of the elastic film 4 and is screwed into the female screw portion 60 of the fitting 6. Female screw part 60
Receives the reduced diameter portion 51 and is screwed with a male screw of the reduced diameter portion 51. The small-diameter holding surface 61 of the fitting 6 facing the back surface of the elastic film 4 is tightly and airtightly attached to the back surface of the elastic film 4 by screwing the reduced diameter portion 51 to the female screw portion 60. Each fitting 6 is formed of a substantially solid metal integrally molded member formed into a predetermined shape, and has a frusto-conical shape that is entirely enlarged from the small-diameter holding surface 61 toward the inside of the hollow region 8. The enlarged inclined surface 65 and the enlarged inclined surface 65
And a substantially frusto-conical reduced inclined surface 66 that generally decreases in diameter from the periphery of the bottom surface 14 to the bottom wall 14, and a substantially horizontal seating surface that extends radially inward from the small diameter periphery of the reduced inclined surface 66. 63. The seating surface 63 faces the fitting bush 7 provided on the bottom wall 14.

The first opening 62 has one end on the enlarged inclined surface 65.
a and the other end of the second opening 62 on the seating surface 63
A through hole 62 opening at b is formed in the fitting 6. The second opening 62b on the seating surface 63 is located on the center axis of the vibration damping units 2 and 3, and the first opening 62a on the enlarged inclined surface 65 is spaced apart from the center axis by a predetermined distance in the radial direction. Position. Therefore, the through hole 62
Are entirely inclined with respect to the center axis, and the second opening 62
“a” is disposed at an interval from the back surface of the elastic film 4. The central shaft 5 and the fitting 6 are made of an integrally molded product or processed product of a metal or alloy such as aluminum, a titanium alloy or a stainless steel alloy, and have a required rigidity and proof strength capable of supporting the experimental equipment E on the support S under gravity. Is provided. On the other hand, the fitting bush 7 is made of a tangible soft material such as a gel-like substance such as silicone gel or a soft rubber or an elastomer molded into a predetermined shape, and abuts or fits the fitting bush 7 under a high gravity of 1 G to 2 G. It has elasticity that can elastically support the fitting 6 that comes into contact.

The fitting bush 7, which is arranged over the entire surface of the bottom wall 14, protrudes along the inner peripheral wall surface of the cylindrical wall body 15, and has a substantially horizontal annular raised surface adjacent to the inner peripheral wall surface. Terminate at 70. A substantially frustoconical side bearing surface 71 extends from the inner periphery of the raised surface 70 toward the bottom wall 14, and a circular flat bottom bearing surface 72 extends radially inward from the bottom edge of the bearing surface 71. Extend to. The bearing surfaces 71, 72
It has a form which is generally complementary to the outer contour of the fitting 6 and forms a concave receiving means capable of receiving the fitting 6. An arc-shaped ridge 73 centered on the center axis of the vibration damping units 2 and 3 is formed in a radially central region of the bottom bearing surface 72. The top of the raised portion 73 is the fitting 6
Is arranged at a position separated by a predetermined distance h from the seating surface 63 of the second member. The hollow region 8 thus defines in the housing 12 a fluid filling zone substantially defined by the cylindrical wall 15, the fitting 6 and the fitting bush 7. A fluid filling tool 9 for filling a liquid having a desired viscosity such as silicone oil into the hollow region 8 is provided on the cylindrical wall 15.

As shown in FIG. 5, the fluid injection pipe 91 of the fluid filling tool 9 has an injection port which penetrates the cylindrical wall body 15 and opens to the hollow region 8 at the distal end. An external thread engraved on the outer peripheral surface of the fluid injection pipe 91 is screwed with a female screw formed in the injection pipe insertion hole of the cylindrical wall 15. The base end of the fluid injection pipe 91 is connected to a first end face of an on-off valve device 93 such as a cock valve. The on-off valve device 93 includes an operating tool 94 such as a rotary lever for opening and closing a valve in the valve device. Prepare. Fluid filling tube 92
Is connected to the second end face of the on-off valve device 93, and the fluid filling pipe 92 has an inflow opening that opens to the side of the vibration damping unit 1. The fluid filling tube 92 is connected to a fluid supply source via a flexible tube or the like at the time of fluid filling, and the operating tool 94 is operated so as to open the valve body of the on-off valve device 93. The fluid of the fluid supply source is injected into the hollow region 8 via the fluid filling pipe 92, the on-off valve device 93, and the injection flow path of the fluid injection pipe 93. The fluid pressure in the hollow region 8 is a desired pressure, for example, 1
When the pressure is increased to the pressure equivalent to the atmospheric pressure, the valve element of the on-off valve device 93 closes the injection flow path.

A fluid discharging device 90 for discharging the fluid filled in the hollow region 8 from the vibration damping units 2 and 3 is disposed on the cylindrical wall 15 at a position facing the fluid filling device 9. The nipple-shaped fluid discharger 90 is provided on the cylindrical wall 15.
An outlet pipe 95 which is screwed into the cylinder wall and penetrates the cylindrical wall body 15;
It is substantially composed of an enlarged portion 97 having a nut structure, and a discharge pipe 96 extending from the enlarged portion 97 to the side of the vibration damping device 1.
A cap 98 for closing the discharge port of the discharge pipe 96 is screwed to an external thread portion of the discharge pipe 96. Upon discharge of the fluid in the hollow area 8, the cap 98 is removed from the discharge pipe 96, and the fluid in the hollow area 8 is discharged from the discharge pipe 95, the enlarged portion 97 and the discharge pipe 9.
The liquid is drained out of the vibration damping device 1 through the flow path 6. As the fluid to be injected into the hollow region 8, for example, silicon oil, water, pure water, ultrapure water, a fluorine-based inert liquid, or
Viscous oils whose viscosity has been appropriately adjusted can be exemplified. The fluid filled in the hollow region 8 suppresses the transmission of vibration disturbance and controls the dynamic behavior of the elastic film 4 by vibrating response of the liquid viscosity to the vibration input.

Each of the vibration damping units 2 configured as described above,
The vibration damping units 3 and 3 are interconnected via a center shaft 5, and the two vibration damping units 2 and 3 stand still at a predetermined interval H at an end face of the holding portion 13 in a microgravity environment as shown in FIG. The seating surface 63 of the fitting 6 is located at a predetermined distance h from the top of the raised portion 73. The distance H is set to a distance that is at least twice the distance h. As shown in FIG. 3, the vibration damping device 1 is positioned at a predetermined position on the upper surface of the support base S, and a fixing tool F1 such as a fixing bolt that can be fastened to the support base S is inserted into the circular through hole 11 of the lower base 10. Is done. By fastening the fixture F1 to the support S,
The vibration damping unit 3 is fixed to the upper surface of the support S. On the other hand, a fixture F2 such as a fixing bolt that can be fastened to the bottom surface of the experimental device E is inserted into the circular through hole 11 of the upper base 10, and is fastened to the experimental device E. As a result, the experimental device E
It is supported on the support base S substantially horizontally via the vibration damping device 1. Thus, the vibration damping device 1 includes the upper surface of the support S,
It is interposed between the lower surface of the experimental equipment E and the like.

FIG. 7 is a perspective view illustrating a use form of the vibration damping device 1. 7, a plurality (four) of vibration damping devices 1 are interposed between the experimental equipment E and the experimental equipment support S. The vibration damping device 1 is positioned at a predetermined position on the upper surface of the support base S corresponding to the square region of the experimental equipment E, and is supported by inserting the fixture F1 into the circular through hole 11 and fastening the fixture F1 to the support base S. It is fixed to the upper surface of the table S. The square area on the bottom surface of the experimental equipment E illustrated in a generally square shape is placed on the vibration damping device 1, and the fixture F2 is inserted into the circular through hole 11 and the fastener F2 is fastened to the experimental equipment E. It is fixed to the upper vibration suppression unit 2. As a result, the experimental equipment E is supported on the support S substantially horizontally via the vibration damping device 1.

FIG. 8 is a diagram showing the relationship between the amount of displacement and the restoring force in the elastic film 4, and FIG. 9 is a response diagram showing the free vibration waveform of the vibration damping device 1. FIG.
FIG. 2 is a longitudinal sectional view showing an operation state of the vibration damping device 1.
3 and 8 to 10, the vibration damping device 1
The operation of will be described. As shown in FIG. 3, the upper and lower vibration damping units 2 and 3 separated by a predetermined distance H in a microgravity environment support the experimental apparatus E on a support S substantially horizontally. The center axis 5 is located at the separated position shown in FIG. 3, and the respective fittings 6 of the upper and lower vibration damping units 2 and 3 are separated from the raised portion 73 of the fitting bush 7 by a predetermined distance h. The load of the experimental equipment E is supported by the support base S via a flexible support system including the sealed fluid in the upper vibration damping units 2 and 3, the elastic film 4 and the central shaft 5,
The axial stress of the central shaft 5 is transmitted as an out-of-plane stress of the elastic film 4. Vibration disturbance such as free vibration, forced vibration, or irregular vibration transmitted to the support base S, or self-excited vibration of a vibration system including the experimental equipment E causes vibration of the elastic films 4 of the vibration damping units 2 and 3. I do. The elastic film 4 having an extremely low elastic restoring force is quickly elastically displaced with respect to vibration of a small amplitude,
A membrane vibration having an amplitude and a frequency in response to the vibration of the center shaft 5 or the housing 12 is generated, and the vibration of the center shaft 5 or the housing 12 is absorbed by dynamic behavior. Therefore, the vibration transmission path between the support base S and the experimental equipment E depends on each elastic membrane 4.
And the mutual transmission of vibration disturbances between the support S and the experimental equipment E is prevented. Further, when a vibration disturbance or a self-excited vibration having a relatively large amplitude acts on the vibration system, the elastic restoring force of the elastic film 4 increases exponentially, and the displacement of the experimental equipment E is suppressed to an appropriate range. To work.

The properties of the amount of displacement of the elastic film 4 in the out-of-plane direction and the elastic restoring force are set to be non-linear as shown in FIG. 8, and the elastic film 4 has a relatively small amount of displacement in the out-of-plane direction. At the same time, it functions as a soft spring that generates a relatively small restoring force, and on the other hand, functions as a hard spring that generates a relatively large restoring force in a region where the displacement amount is relatively increased. FIG. 8 shows that the elastic film 4 is 1 kg / mm ² , 3 kg / mm ² and 5 kg / mm ^2.
For a case with an equivalent elastic modulus E (Eeq) of mm ² ,
The functions of the displacement and the restoring force are illustrated. Since the internal pressure of the vibration damping units 2 and 3 fluctuates with the change in the volume of the liquid filled in the liquid chambers (hollow regions 8) in the vibration damping units 2 and 3, the equivalent elastic modulus shown in FIG. E is an equivalent elastic coefficient in the in-plane expansion and contraction direction of the elastic film 4 that can be set as a result of reflecting the effect or effect of the restoring force due to the internal pressure fluctuation. This is adopted as an index for indicating the elastic coefficient of the film 4. The equivalent elastic modulus of the elastic film 4 can be appropriately set in accordance with the mass of the supported body such as the experimental device E and the suitable response frequency characteristics of the vibration damping device 1. As the elastic film 4 of the present example,
Preferably, a material having an equivalent elastic modulus of about 1 to 15 kg / mm ² , more preferably about 3 to 10 kg / mm ² can be selected. The elastic film 4 under the microgravity environment forms a flexible support system that supports the experimental equipment E with an extremely small restoring force, and inputs (disturbance vibration) that can be transmitted to the experimental equipment E via the support base S. Insulated and laboratory equipment E
Is held substantially and stably at rest. Further, the out-of-plane deformation of the elastic film 4 causes a change in the fluid pressure in the fluid accommodating region 8 and increases the tensile stress of the elastic film 4 due to local expansion and local contraction of the elastic film 4. The tensile stress acts as an out-of-plane restoring force of the elastic film 4, and as a result, the elastic restoring force of the elastic film 4 increases relatively sharply as shown in FIG. Accordingly, when a vibration disturbance having a relatively large amplitude is transmitted to the support base S in a microgravity environment, the elastic film 4 relatively sharply accompanies the out-of-plane deformation of the film member constituting surface as shown in FIG. Increase resilience,
A relatively large elastic restoring force corresponding to the amplitude of the vibration disturbance regulates the displacement of the experimental equipment E to a value within an appropriate range and suppresses the vibration disturbance.

On the other hand, under the gravitational environment, the upper vibration damping unit 2 and the central shaft 5 are displaced downward as a whole by the load of the experimental equipment E, and the respective fittings 6 of the upper vibration damping unit 2 and the lower vibration damping unit 3 are As shown in FIG. 10, the fitting bush 7 is seated on the concave support portions (the support surfaces 71, 72 and the raised portion 73). The raised portion 73 elastically abuts or abuts on the seating surface 63 of the fitting 6 and is flattened by the load of the experimental equipment E, and the side bearing surface 71 abuts or abuts on the reduced inclined surface 66 of the fitting 6. . As a result, the upper and lower vibration damping units 2 and 3 stop at a position separated by the distance Hs. With the relative displacement of the fitting 6 and the fitting bush 7, the fluid interposed between the fitting 6 and the bush 7 causes the fluid between the fitting 6 and the elastic membrane 4 to pass through the gap around the fitting 6 and the through hole 62. Out into the area. The elastic membrane 4 is used to compensate for a change in volume of the fluid containing area 8 as shown in FIG.
As shown in FIG. Thus, the vibration damping device 1 in the directly connected position where the fitting 6 is seated on the bush 7.
Is connected to the central shaft 5 via the fitting 6 and the bush 7.
The stress in the vertical direction is transmitted directly to the support table S, and the load of the experimental equipment E is supported with relatively high strength substantially without the intervention of the elastic film 4. Further, due to the flexibility of the appropriate fitting bush 7, vibration disturbance to the vibration system of the experimental equipment E is appropriately damped.

FIG. 9 exemplifies a free vibration waveform of the vibration damping device 1 in which the position of the elastic film 4 at the separated position (FIG. 3) is the origin (Omm) of the displacement amount. As a result of forcibly bringing the upper and lower vibration damping units 2 and 3 close to each other by about 1 cm and releasing the vibration damping units 2 and 3, the free vibration of the vibration damping device 1 is substantially reduced within about 2 seconds. Attenuated. Therefore, when the environment changes from a high-gravity environment such as the ground to a low-gravity environment, the vibration damping device 1 moves from the direct connection position (FIG. 10) to the separation position (FIG. 3).
However, the vibration acting on the vibration damping device 1 due to the displacement quickly converges due to the viscous damping caused by the viscosity of the fluid in the fluid storage area 8.

As described above, the passive type vibration damping device 1 includes the upper vibration damping unit 2 and the lower vibration damping unit 3 having the housing 12 capable of storing the liquid, and the upper vibration damping unit and the lower vibration damping unit 3 separated by a predetermined distance. And a center shaft 5 interconnecting the vibration damping units 2 and 3. The upper and lower vibration damping units 2 and 3 each have an elastic film 4 made of a flexible material,
The elastic membrane 4 closes the liquid sealing area 8 formed in the housing 12. Both ends of the central shaft 5 are connected to the elastic film 4 so as to be integrally displaceable with the central region of the elastic film 4 by fastening the reduced diameter portion 51 to the fitting 6. An out-of-plane response vibration is generated in response to a vibration disturbance transmitted through the actuator 50. According to the configuration of the vibration damping device 1, the vibration disturbance acting on the vibration system is:
The vibration is attenuated by the vibration response effect of the viscosity of the fluid sealed in the fluid storage area 8 and the vibration response effect of the elastic displacement of the elastic film 4. In addition, the elastic film 4 transiently moves the shaft member 5.
The internal force acting on the elastic film 4 due to the elastic restoring force of the elastic film 4 which increases relatively rapidly according to the out-of-plane deformation of the elastic film 4 in response to an excessive vibration input inputted to the elastic film 4 via While resisting an increase in stress, the out-of-plane rigidity of the elastic film 4 prevents amplification of the vibration of the shaft member 5. Further, the reduced diameter portion 51 of the shaft member 4 penetrates the elastic membrane 4 and
Reach inside. The fitting 6 fastened to the compression system portion 51 includes a seating surface 63 and a reduced inclined surface 66 that can be displaced integrally with the shaft member 5 and the elastic film 4. A fitting bush 7 is provided in the fluid containing area 8, and the fitting bush 7 is formed of an elastic material provided on the bottom wall 14 of the fluid containing area 8. The seating surface 63 and the reduced inclined surface 66 of the fitting 6 can elastically seat on the side bearing surface 71 and the arc-shaped ridge 73 of the fitting bush 7.

The vibration system including the experimental equipment support S, the experimental equipment E, and the vibration damping device 1 is arranged in an environment accompanied by a large change in gravity. The elastic films 4 of the respective vibration damping units 2 and 3 separated by a predetermined distance have a component surface orthogonal to the center axis of the shaft member 5, and the shaft member 5 enables the upper and lower elastic films 4 to transmit stress. Interconnect. The experimental equipment E includes a membrane member 4 and a shaft member 5
And the sealed fluid in the fluid storage area 8 that is entirely in contact with the constituent surface of the membrane member. The elastic film 4 elastically deforms under the pressure of the sealed fluid in a high gravity environment such as on the ground, the fitting 6 is seated on the fitting bush 7, and the shaft member 5 is connected via the fitting 6 and the fitting bush 7. The shaft unit 50, the experimental equipment E, and the support S are interconnected so as to directly transmit stress, and in such a directly connected position, the experimental equipment E is supported on the support S by substantially the supporting force or strength of the shaft 50. I do.

When the surrounding environment changes to a microgravity environment,
The fitting 6 is separated from the fitting bush 7 by the elastic restoring force of the elastic film 4, and the shaft member 5 releases a direct stress transmission path of the shaft portion 50, the experimental equipment E, and the support S. When the fitting 6 separates from the bush 7, the fluid in the region between the fitting 6 and the elastic membrane 4 flows between the seating surface 63 and the arc-shaped ridge 73 through the through hole 62, The fitting 6 quickly detaches, and the elastic membrane 4 smoothly returns to the flat position. In such a separated position, the vibration damping device 1 interconnects the experimental equipment E and the support base S via the elastic membrane 4 and the sealed fluid so that stress can be transmitted, and substantially connects the experimental equipment E to the elastic membrane 4. And it is supported on the support base S by the enclosed fluid. In a microgravity environment such as a space environment, the experimental equipment E is provided with an elastic film 4
The vibration transmitted between the experimental equipment E and the support S is supported on the experimental equipment support S by the out-of-plane rigidity of the elastic film 4.
And damping due to the vibration response characteristics of the enclosed fluid.

FIG. 11A is a longitudinal sectional view showing the entire structure of a vibration damping device according to a second embodiment of the present invention and the orifice structure of the vibration damping device. In the vibration damping device shown in FIG. 11, components or components substantially the same as those of the vibration damping device of the first embodiment are denoted by the same reference numerals. As shown in FIG. 11A, the vibration damping device 1 of this example includes upper and lower vibration damping units 2 and 3 having substantially the same structure as the vibration damping device of the first embodiment. However, the hollow region 8 of the housing 12 communicates with the outside atmosphere of the vibration damping device 1 via the fluid communication device 100. The fluid communication device 100 includes a first fluid communication pipe 101 penetrating the cylindrical wall body 15.
The communication pipe 101 has a vent at the distal end that opens into the hollow region 8. An outer screw on the outer peripheral surface of the communication pipe 101 is screwed with a female screw formed in a through-hole of the cylindrical wall body 15, and the communication pipe 1 is formed.
01 airtightly engages the cylindrical wall 15.

The communication pipe 101 is connected to an open-air pipe 102 via a throttle valve device 103 whose opening ratio can be variably controlled. Each of the communication pipe 101 and the open pipe 102 is connected to the valve element 1.
06 and the valve seat of the throttle valve device 103 defined by the valve seat, the valve body 106 is connected to the valve opening / closing operation mechanism 104 in accordance with the rotational position of the valve opening / closing operation. The flow area is variably set. Thus, the throttle valve device 10
3. Communication channel 105 that can variably control fluid communication at 3
Are formed between the hollow region 8 and the outside atmosphere. FIG.
The vibration damping device 1 interposed between the experimental equipment support base S and the experimental equipment E as shown in FIG. 1 responds to various vibration disturbances or self-excited vibrations acting on the support base S and the equipment E. A few elastic films 4 are vibrated. The elastic film 4 is quickly elastically displaced in response to a vibration of a small amplitude acting in a microgravity environment, and a film vibration of an amplitude and a frequency in response to the vibration of the center shaft 5 or the vibration of the housing 12 is generated. In response to the volume change of the hollow region 8 caused by the elastic displacement of the elastic film 4, the gas or gas in the hollow region 8 flows out from the communication channel 105 to the outside, and the external atmosphere passes through the communication channel 105. Flows into the hollow region 8 via

The opening of the throttle valve device 103 constituting the fluid communication device 100 is arbitrarily set to an appropriate opening capable of exhibiting an appropriate vibration damping effect based on various experiments or test data conducted in advance. You. The valve opening of the throttle device 103 whose flow path area is restricted by the valve body 106 regulates the fluid flow flowing between the hollow region 8 and the external region (outside atmosphere), and reduces the local flow resistance. It functions as an orifice for the flow. The gas flow or gas flow passing through the orifice is subjected to frictional resistance due to gas friction, and the frictional resistance acts as a damping force for gas vibration in the hollow region 8. Thus, when the fluid in the hollow region 8 sucked and exhausted through the throttle valve device 103 flows through the orifice formed in the valve opening, the fluid undergoes an energy damping effect due to gas friction, and as a result, the communication flow The vibration energy or pulsation energy of the fluid flowing into and out of the vibration damping device 1 through the passage 105 is attenuated by the vibration damping effect of the orifice. Such an energy damping action acts on the elastic membrane 4 as a vibration damping force, damping the vibration of the elastic membrane 4, and therefore, the vibration that can be transmitted between the support S and the experimental equipment E is a response of the vibration membrane 4. Attenuates as the vibration decreases and the amplitude converges.

In this embodiment, the material, physical properties and function of the elastic film 4, the vibration damping action of the elastic film 4 itself, or the structure and function of other components or components constituting the vibration damping device 1, Further, the operation mode and the like of the vibration damping device 1 displaced to the direct connection position under a high gravity environment such as on the ground are substantially the same as those described in the first embodiment, and thus a further detailed description will be made. Omitted.

FIGS. 11B, 11C and 11D are schematic sectional views of an orifice structure illustrating various forms of the orifice. The orifice of the vibration damping device 1 can be formed not only as a variable orifice whose opening ratio or opening can be variably set as in the throttle valve device 103, but also as a fixed orifice set to a predetermined opening ratio in advance. be able to. Orifice 1 that can be arranged in communication channel 105
07 are illustrated in FIGS. 11B, 11C, and 11D. As the structure and form of the orifice 107, various cross-sectional characteristics protruding inward of the communication flow path 105, for example, a rectangular protrusion (FIG. 11B), a triangular protrusion (FIG. 11C), or a semicircular protrusion Various structures and forms such as a part (FIG. 11D) can be adopted.

FIG. 12 is a perspective view and a partially enlarged sectional view of a vibration damping device 1 showing a modification of the fluid communication device. FIG.
The vibration damping device 1 shown in (A) includes a bolt-shaped or screw-shaped fluid communication device 110 having a flow path 112 having a predetermined inner diameter. As shown in FIG. 12B, the fluid communication device 110
Includes a head portion 111 having a relatively large diameter and a shank portion 113 having a relatively small diameter. Shank part 1 with external thread
The reference numeral 13 penetrates the cylindrical wall 15 of the housing 12 and hermetically screw-engages the wall 15. The flow channel 112 arranged at the center axis position of the fluid communication device 110
The hollow region 8 and the outside atmosphere are communicated with each other through the shank portion 113.

In use, a plurality of fluid communication devices 110 having channels 112 of different diameters are prepared in advance. For example, the first fluid communication device 110 shown in FIG.
With a channel 112 having a relatively large diameter, FIG.
The second fluid communication device 110 shown in (D) includes a channel 112 having a relatively small diameter. The first and second fluid communication devices 110 are appropriately selected according to the type and conditions of the gas or gas held in the hollow region 8 and the environmental conditions of the external atmosphere. (Screw hole) so as to be exchangeable. Channels 112 having substantially the same inner diameter over their entire length constitute an orifice as a whole. By appropriately setting the total length and the diameter of the flow path 112, the action of the gas passing through the fluid communication device 110 or the fluid friction acting on the gas is regulated, whereby the vibration damping action of the vibration damping device 1 is appropriately controlled. You. By exchanging the fluid communication device 110, the vibration damping effect of the vibration damping device 1 is variably set, and exhibits an appropriate vibration damping effect suitable for the intended use.

FIGS. 13 and 14 are perspective views of the vibration damping device 1 showing a further modified example of the vibration damping device 1. FIG. As the gas or gas to be held in the hollow region 8 of the vibration damping device 1, air or clean air can be generally exemplified. However, as the fluid to be charged into the hollow region 8, various special gases depending on the purpose of use can be appropriately used. For example,
An inert gas such as a nitrogen gas, a carbon dioxide gas, or an argon gas can be loaded into the hollow region 8 with an emphasis on the noncombustibility of the gas. The vibration damping device 1 shown in FIG. 13 and FIG. 14 is provided with a fluid conduit 121 for filling and holding such a specific gas in the vibration damping device 1. The upstream end portion of the fluid conduit 121 is
Connected to a suitable gas source (not shown) (FIG. 13), or a gas filled accumulator or pressure regulating tank 12
2 (FIG. 14).

The downstream end of the fluid line 121 is connected to the line connecting portion 1.
It is connected to the cylindrical wall 15 of the housing 12 via 20. A conduit connection 120 having a suitable inner diameter penetrates the cylindrical wall 15 and interconnects the hollow region 8 and the fluid conduit 121. It flows out of the hollow region 8 through the relatively small-diameter conduit connection portion 120 and the fluid conduit 121 or
The inert gas or the like flowing into the inside receives the damping force due to the resistance of the flow paths in the pipes 120 and 121, and suppresses the gas vibration of the hollow region 8 and the film vibration of the elastic film 4. In addition, the pipe connection part 120 is provided with a suitable diameter reducing means which protrudes inward as shown in FIGS. 11 (B), (C) and (D), if desired.

As described above, in the vibration damping device 1 according to the second embodiment, the vibration damping device 1 holds gas or gas in the hollow region 8, and the hollow region 8 is a valve device that functions as an orifice. , And communicate with the outside atmosphere or a gas source through a reduced diameter portion or a small diameter pipeline. The vibration damping device 1 generates a response vibration of the elastic film 4 in an out-of-plane direction with respect to a vibration disturbance transmitted through the shaft portion 50 of the center shaft 5, and
Not only attenuates the vibration by the vibration response action due to the elastic displacement of the gas, but also receives the vibration damping force by the gas or the gas friction of the gas in the hollow area 8 controlled to be sucked and discharged through the orifice. The vibration of the membrane 4 is damped. The vibration damping device 1 also has an elastic restoring force of the elastic film 4 which increases relatively rapidly according to the out-of-plane deformation of the elastic film 4 and a fluid flow resistance of the orifice with respect to a vibration input having an excessive amplitude. In addition to preventing the internal stress acting on the central shaft 5 from increasing, the vibration of the central shaft 5 is prevented from being amplified by the out-of-plane rigidity of the elastic film 4 and the damping action of the fluid passing through the orifice.

It should be noted that the present invention is not limited to the above embodiment, and various modifications or changes can be made within the scope of the present invention described in the appended claims. Needless to say, they are included in the scope of the present invention. For example, the elastic film 4 is not limited to a circular or disk shape, but may be formed into various shapes such as an ellipse, a square, a triangle, a quadrangle, or a polygon.
It is also possible to form Further, the shapes or outer contours of the central shaft 5 and the housing 12 are not limited to a columnar shape or a cylindrical shape. A form may be employed. Further, the center shaft 5 may be formed in a hollow shape or a double tube structure.

Further, a bypass pipe for interconnecting the hollow regions 8 of the upper and lower vibration damping units 2 and 3 is provided in the vibration damping device 1 as a fluid pressure adjusting means, or a fluid in the hollow region 8 is provided. It is also possible to provide an accumulator or an additional membrane member with adjustable pressure on the vibration damping device 1. Further, a plurality of the fluid communication devices 100 and 110 that allow the hollow region 8 to communicate with the outside atmosphere may be provided in the housing 12. Further, the fluid communication device 100,
Various types of valve structures, such as a butterfly valve structure, a gate valve structure, or a regulating valve structure, can be appropriately adopted as the structure type of the throttle valve constituting 110.

[0044]

According to the above configuration of the present invention, the flexible and flexible support can be maintained against the stable vibration disturbance, the transmission of the vibration input can be effectively insulated, and the vibration system can be oversized. Provided is a passive vibration damping device and a vibration damping method capable of supporting a supported member with relatively high rigidity when a vibration input or excitation force having a large amplitude acts or a steady acceleration acts on the entire vibration system. It is possible to do. Further, according to the above configuration of the present invention, in various experiments utilizing the specialty of the microgravity environment, the vibration disturbance input to the vibration system including the experimental apparatus or the experimental equipment is effectively insulated, and the influence of the vibration disturbance is reduced. It is possible to provide a passive vibration damping device and a vibration damping method that can realize a favorable experimental environment that is difficult to receive. Further, according to the above configuration of the present invention, it is possible to use as desired in a vibration system in which a vibration input or an excitation force having an unpredictable vibration characteristic can be applied due to a sudden and wide fluctuation of the surrounding environment or surrounding atmosphere. In addition to avoiding rapid vibration amplification or resonance phenomenon of the vibration system including the vibration damping device, it can also exhibit effective vibration damping performance against amplitude fluctuations of a wide range of vibration systems. It is possible to provide a passive damping device and a vibration damping method that can be obtained.

[Brief description of the drawings]

FIG. 1 is a perspective view showing an overall configuration of a vibration damping device according to a first embodiment of the present invention.

FIG. 2 is an exploded perspective view of the vibration damping device shown in FIG. 1 in a state where the vibration damping device is divided on a central horizontal plane.

FIG. 3 is a longitudinal sectional view showing the entire structure of the vibration damping device shown in FIGS. 1 and 2, including a partially enlarged view of an elastic membrane supporting structure (“A” portion).

FIG. 4 is a sectional view of the vibration damping device taken along the line VI-VI in FIG. 3;

FIG. 5 is a cross-sectional view of the vibration damping device taken along line VV in FIG. 3;

6 is a cross-sectional view of the vibration damper taken along line IV-IV in FIG.

FIG. 7 is a perspective view illustrating a usage form of the vibration damping device shown in FIGS. 1 to 7;

FIG. 8 is a diagram showing a correlation between an amount of displacement and an elastic restoring force of an elastic film provided in the vibration damping device shown in FIGS. 1 to 7;

9 is a free vibration response diagram showing a free vibration waveform of an elastic film provided in the vibration damping device shown in FIGS. 1 to 7. FIG.

FIG. 10 is a longitudinal sectional view showing an operation mode of the vibration damping device shown in FIGS. 1 to 7 at a position directly connected to a shaft member.

FIG. 11 is a longitudinal sectional view showing an entire structure of a vibration damping device according to a second embodiment of the present invention and an orifice structure in the vibration damping device.

12 is a perspective view and a partially enlarged sectional view of a vibration damping device showing a modification of the vibration damping device shown in FIG.

FIG. 13 is a perspective view of a vibration damping device showing a further modified example of the vibration damping device shown in FIG.

FIG. 14 is a perspective view of a vibration damping device showing still another modified example of the vibration damping device shown in FIG.

[Explanation of symbols]

 REFERENCE SIGNS LIST 1 damping device 2 upper damping unit 3 lower damping unit 4 elastic film 5 center axis 6 fitting 7 fitting bush 8 hollow area (fluid accommodation area) 10 base 11 circular through hole 12 housing 13 membrane member holding portion 14 bottom wall 15 Cylindrical wall 50 Shaft part 51 Reduced diameter part 52 Enlarged diameter part 60 Female screw part 61 Small diameter clamping surface 62 Through hole 63 Seating surface 65 Enlarged inclined surface 66 Reduced inclined surface 70 Raised surface 71 Side bearing surface 72 Bottom bearing surface 73 Arc-shaped ridge 100, 110 Fluid communication device 105 Communication flow path 107 Orifice 120 Pipe connection section 121 Fluid pipe H, h, Hs Interval (distance) FI, F2 Fixture S Experimental equipment support E Experimental equipment

Claims (25)

[Claims] 1. A vibration damping function which is interposed between a supporting member and a supported member constituting the vibration system so as to restrict the transmission of vibration of the vibration system due to vibration disturbance acting on the vibration system. A passive vibration damping device having a flexible vibration response member, wherein a first vibration damping unit and a second vibration damping unit each having a housing are interconnected with the first and second vibration damping units separated by a predetermined distance. The first and second vibration damping units each have an elastic film made of a flexible material, and both end portions of the shaft member are displaceable integrally with the elastic film. The elastic film is connected to each elastic film of the first and second vibration damping units, and the elastic film generates an out-of-plane response vibration to a vibration disturbance transmitted through the shaft member, and the elastic film has an elasticity. The vibration disturbance is attenuated by a vibration response action by displacement, In response to an excessively large vibration input that is transiently input to the elastic film through the shaft member, the elastic film has an elastic restoring force of the elastic film that increases according to out-of-plane deformation of the elastic film. A passive vibration damping device that resists an increase in internal stress acting on an elastic film and prevents amplification of vibration of the shaft member by out-of-plane rigidity of the elastic film. 2. The housing has an internal structure forming a fluid storage area capable of storing a fluid, and the elastic film includes:
The fluid accommodating region is closed, and the elastic film attenuates the vibration disturbance by a vibration response effect due to viscosity of a fluid sealed in the fluid accommodation region and a vibration response effect due to elastic displacement of the elastic film. The passive vibration damping device according to claim 1, wherein: 3. The housing according to claim 1, wherein the housing has an internal hollow area that is in communication with an external atmosphere or an external gas area, and a constituent surface of the elastic membrane faces the hollow area. Passive damping device. 4. The shaft member penetrates the elastic film and extends into an internal region of the housing, and the extending portion of the shaft member is displaceable integrally with the shaft member and the elastic film. A seating portion, wherein the inner region of the housing includes a bearing surface on which the seating portion can resiliently seat, and the bearing surface is formed of an elastic material disposed on a bottom wall of the inner region of the housing. The passive vibration damping device according to any one of claims 1 to 3, wherein: 5. A relative distance between the respective housings constituting the first and second vibration damping units is set to a distance exceeding twice a relative distance between a seating surface of the seating portion and the bearing surface. The passive vibration damping device according to claim 4, wherein: 6. The passive member according to claim 1, wherein an axis of the shaft member is oriented so as to be substantially orthogonal to a constituent surface of the elastic film. Mold damping device. 7. The vibration damping unit according to claim 1, wherein the first and second vibration damping units are formed so as to be symmetric with respect to a center plane of the vibration damping device. Passive damping device. 8. The fluid, comprising a liquid having a predetermined viscosity, sealed in the fluid storage area formed in the housing and closed by the elastic film, and the elastic face facing the fluid storage area. 3. The passive vibration damping device according to claim 2, wherein the passive vibration damping device is in contact with the entire constituent surface of the membrane. 9. The method according to claim 3, wherein the hollow region is interconnected with an outside atmosphere or an external gas region via an orifice means, and the fluid is made of a gas which can flow through the orifice means. Passive damping device. 10. The elastic membrane according to claim 1, wherein the elastic membrane has a generally circular contour, and a center of the elastic membrane substantially coincides with a center axis of the shaft member. 2. The passive vibration damping device according to claim 1. 11. The passive surface according to claim 4, wherein the bearing surface defines a recess in the bottom area of the inner region of the housing, the recess being capable of at least partially receiving the seating portion. Mold damping device. 12. The seating portion includes an enlarged member fixed to each end of the shaft member, and an outer contour of the enlarged member has a shape substantially complementary to a concave shape of the bearing surface. The seating surface of the seating portion is formed by a bottom surface and / or a side surface of the enlarging member, and the bearing surface is formed by a bottom wall surface and / or a side wall surface of the recess. Comprises a fluid communication path that interconnects a first intermediate region between the elastic membrane and the expanding member and a second intermediate region between the bearing surface and the seating surface. The passive vibration damping device according to claim 11. 13. A vibration damping method for interposing a flexible member between a supported member and a support member constituting a vibration system on which a vibration disturbance acts to attenuate vibration of the vibration system due to the vibration disturbance. The vibrating system is disposed under an environment with gravitational fluctuation, a plurality of flexible membrane members spaced at a predetermined interval, and is oriented in a direction intersecting the constituent surface of the membrane member and capable of transmitting stress to the membrane member. The supported member is placed on the support member through a shaft member interconnected with the supporting member, and the supported member is supported on the support member by the out-of-plane rigidity of the membrane member in a low gravity environment. A vibration damping method, wherein the vibration transmitted between the supported member and the support member is attenuated by a vibration response characteristic of the membrane member. 14. In a high gravity environment, the shaft member is displaced by a deformation of the film member to a directly connected position where an axial stress of the shaft member is directly transmitted to the supported member and / or the support member. And supporting the supported member on the support substantially by the support force of the shaft member. Under a low gravity environment, the elastic restoring force of the film member reduces the axial stress of the shaft member. Displacing the shaft member to a separated position for transmitting to the membrane member, releasing a direct stress transmission path between the shaft member and the supported member and / or the support member, and allowing the shaft member to move through the membrane member; 14. The method of claim 13, wherein the support and the support are interconnected so as to transmit stress, and the supported body is substantially supported on the support by the membrane member. 15. The method according to claim 15, wherein the supporting member is placed on the supporting member via the flexible film member and the shaft member, and a sealed fluid that is entirely in contact with a constituent surface of the film member. The vibration damping method according to claim 13 or 14, wherein 16. In a low gravity environment, the supported member and the support member are interconnected so that stress can be transmitted through the film member and the sealed fluid, and the supported member is substantially connected to the film member and the sealing member. The vibration damping method according to claim 15, wherein the support is supported on the support by the sealed fluid. 17. An elastically deformable soft member is interposed between the shaft member and the supported member and / or the support member, and the soft member is connected to the shaft member at a position directly connected to the shaft member. While elastically supporting the end of the shaft member so that stress can be transmitted, and ensuring a separated state between the membrane members, wherein the soft member is configured such that the shaft member, the supported body, and 17. A shaft as claimed in any one of claims 14 to 16, characterized in that it is spaced from an end of the shaft member so as to release a direct stress transmission path between the shaft member and the support.
The vibration damping method according to the item. 18. The method according to claim 15, wherein the pressure fluctuation of the sealed fluid is compensated by elastic deformation of the membrane member.
Or the vibration damping method according to 16. 19. The storage area for the sealed fluid is interconnected with an outside atmosphere or an external gas area via an orifice means, and the sealed fluid is made of a gas which can flow through the orifice means, and the capacity of the storage area is 17. The vibration damping method according to claim 15 or 16, wherein the sealed fluid flowing through the orifice means in response to the fluctuation is subjected to a gas friction action of the orifice means. 20. The elastic member according to claim 13, wherein the elastic restoring force of the film member has a non-linear elastic body characteristic and increases relatively sharply with an increase in the amount of displacement of the film member. 20. The vibration damping method according to any one of claims 19 to 19. 21. The fluid according to claim 15, wherein the fluid is silicone oil.
The vibration damping method according to the item. 22. The vibration damping method according to claim 17, wherein the soft member is a silicon gel. 23. The method according to claim 19, wherein the gas is an inert gas. 24. The housing includes an orifice means defining a fluid storage area capable of storing a fluid, and interconnecting the fluid storage area in fluid communication with an external environment or an external fluid area of the housing. An elastic membrane closes the fluid storage area, and the elastic membrane attenuates the vibration disturbance due to a vibration response action due to the viscosity of the fluid sealed in the fluid storage area and a vibration response action due to the elastic displacement of the elastic membrane. The passive vibration damping device according to claim 1, wherein the orifice means generates a vibration damping force of the elastic film by a frictional action of a fluid flowing through the orifice means. 25. A constituent surface of the membrane member defines a fluid accommodating region capable of accommodating a fluid, the membrane member having a vibration response effect due to the viscosity of a fluid accommodated in the fluid accommodating region and the membrane member. The vibration disturbance is attenuated by a vibration response effect of the elastic displacement of the fluid storage region, and the fluid storage region communicates with the outside or an external fluid region through an orifice means, and the fluid corresponds to a volume change of the fluid storage region. Flowing through the orifice means,
14. The vibration damping method according to claim 13, wherein a frictional force of the fluid generated when passing through the orifice means acts on the membrane member as a vibration damping force of the vibration system.