CN101036245A

CN101036245A - Active/passive distributed absorber for vibration and sound radiation control

Info

Publication number: CN101036245A
Application number: CNA2005800335589A
Authority: CN
Inventors: 克里斯托弗·R·福勒; 凯瑟琳·孔季拉斯
Original assignee: Virginia Tech Intellectual Properties Inc
Current assignee: Virginia Tech Intellectual Properties Inc
Priority date: 2004-08-02
Filing date: 2005-07-29
Publication date: 2007-09-12
Also published as: JP2008508493A; KR20070044478A; EP1774510A2; EP1774510A4; AU2005274088A1; WO2006020416A2; WO2006020416A3; JP5070527B2

Abstract

The active/passive absorber for extended vibration and sound radiation control includes principally two layers. The first layer has a low stiffness per unit area which allows motion in the direction perpendicular to its main plane. The second layer is principally a mass layer. These two combined layers have a frequency of resonance close to one of the main structure. The dynamic behavior of the coupled system makes the active/passive absorber a passive absorber; however, the first layer can be electrically actuated to induce motion in the direction perpendicular to its main plane. This addition property induces and/or changes the motion of the mass layer and therefore improves the dynamic properties of the active/passive absorber system. The active/passive absorber can have multiple mass layers and multiple elastic layers stacked one on top of the other. In addition, the mass layers can be continuous or discretized, and have varying thicknesses and shapes for sections and/or segments in the mass layer.The active/passive absorber for extended vibration and sound radiation control includes principally two layers (402) the first layer has a low stiffness per unit area which allows motion in the direction perpendicular to its main plane. The second layer is principally a mass layer (400'). These two combined layers have a frequency of resonance close to one of the main structure. The dynamic behavior of the coupled system makes the active/passive absorber a passive absorber; however, the first layer can be electrically actuated to induce motion in the direction perpendicular to its main plane. This additional property induces and/war changes the motion of the mass layer and therefore improves the dynamic properties of the active/passive absorber system. The absorber can be provided as multiple layers.Vibration or acoustic sound control is achieved using an elastic layer of thermal or insulation material in which a plurality of discrete masses are distributed throughout.

Description

Be used to control the distributed absorber of active of vibration and sound radiation

Technical field

The present invention relates generally to vibration isolator, relate more specifically to be used to control the distributed vibration isolator of active of vibration and sound radiation.

Background technology

Initiatively and passive noise reduction control technology be extensive known and be generally used for reducing and/or be controlled at the vibrating body for example vibration in the aircraft etc. and the acoustic radiation of following.The active noise reduction technology reduces vibration and noise fully under many situations, is cost with expensive and complicated control system still.Similarly, the passive noise reduction technology of also known minimizing vibration and noise, but these passive systems typically volume is big and heavy, and on low vibration frequency, be not effective.

Basically, the active vibration control system is used and is detected from the vibration of vibrating body and the transducer of noise.Transducer will vibrate or noise is transformed into signal, reverse then and amplify this signal.The signal feedback that to reverse is vibrated or noise thereby reduce to the actuator (or loudspeaker) that reverse signal is provided to vibrating body then.The ACTIVE CONTROL system is for example typically effective below the 1000Hz at low frequency.

In order to utilize the ACTIVE CONTROL system suitably, to the functional key of ACTIVE CONTROL system is the selection of right sensors and actuator.That is to say that if selected inappropriate transducer and actuator, the ACTIVE CONTROL system can not reverse and amplifying signal suitably, and therefore can not reduce the vibration and the noise of vibrating body fully.Transducer on the vibrating body and actuator also are crucial to the function of active vibration control system relative to each other and with respect to the suitable location of the vibration relevant with vibrational structure.For example, if transducer and actuator are not positioned properly, can not amplify the signal of counter-rotating suitably in order to offset the vibration on the vibrating body.In addition because corrective feedback loop determines the validity and the frequency range thereof of vibration control, so have can reverse signal this loop be very important.

System compares with ACTIVE CONTROL, the passive damping system simple many and considerably cheaper.But this damping system volume greatly and only effective in the frequency that is higher than 500Hz.Size in these big wavelength place passive damping systems is suitable with the wavelength of vibrating body vibration really.

In the practice of vibration control system, also commonly make up initiatively and passive vibrational system.But, this mixing active dynamic vibration control system at passive system by being to provide improved decay on the cost basis of realizing to add energy to system via control.

The point tuning damper is the other method of damping vibration body vibration.But the some absorber only is controlled at a frequency of a point, so its function of controlling vibration on the large tracts of land of vibrating body is limited.

Summary of the invention

The purpose of this invention is to provide distributed active damper and distributed passive vibration isolator.

Another object of the present invention provides the distributed active damper that comprises the transducer that is used to detect vibration, is used for the mechanism of controlled signal and uses control signal to realize the feedfoward control and/or the feedback control strategies of vibration isolator.

According to the present invention, provide distributed active damper with a plurality of resonant layers.In in an embodiment one, ground floor comprises the active elastic layers that preferably has low per unit area rigidity.The second layer is a quality layers, and adheres on the part at the top of each wavy part of active elastic layers.Resonant layer comprises the combination of active elastic layers and quality layers then.So a plurality of resonant layers can be positioned at the top of each other, and these resonant layers can have discrete mass (not being connected and not forming the quality of integral body " layer ") identical or varying dimensions and shape (for example ball bearing, thin flattened rectangular etc.).In another embodiment, initiatively and passive vibration level comprise elastomeric material, for example foam, glass fibre, polyurethane, rubber or materials similar, and quality layers to be distributed in elastomeric material interior or be fixed on the surface of elastomeric material.Quality layers can be made of the discrete mass fragment of different size, thickness or shape.In addition, actuator, for example polyvinylidene fluoride (PVDF), piezoelectric ceramic or other electromechanical assembly can embed in the elastomeric material.

Active elastic layers has low rigidity, and this allows along moving perpendicular to the direction of active elastic layers primary flat.Can also actuate active elastic layers electrically to bring out motion perpendicular to its primary flat.Should additional characteristic allow controller to bring out and/or change the motion of quality layers, thereby improve the dynamic characteristic of whole system.These two combination layers can have the resonance frequency that depends on main structure and rigidity, and preferably resonance frequency near one frequency in the main structure.

Active elastic layers can be crooked polyvinylidene fluoride (PVDF) layer; But it also can be piezoelectric ceramic, PZT rubber, electromechanical assembly etc.In addition, active elastic layers can also be made of the PVDF of complete bending, makes ripple surround fully and becomes the tubular structure that supports quality layers.Active elastic layers is included in its lip-deep electrode, makes can actuate active elastic layers electrically when voltage is applied between first and second electrodes.This electric power is actuated the generation electric field.What further be susceptible to is that active elastic layers can be a piezoelectric, and this piezoelectric mechanically shrinks and expands under electric field effects.For this reason, the distance between two planes of quality layers both sides changes when active elastic layers is mechanically shunk under electric field effects and expanded.

Preferably the quality of quality layers is no more than the about 10% of vibrational structure gross mass, and the weight on the per unit area of the thickness of quality layers and vibrational structure is proportional.But, it should be understood that quality layers can be more than 10% of this vibrational structure gross mass.The present invention further is susceptible to is that the attitude contribution situation of shaking that has a little amplitude with vibrational structure wherein compares, and vibrational structure has under the situation of the attitude contribution of shaking of large amplitude and has quality layers bigger on area therein.

According to the attitude contribution of shaking of vibrating body, quality layers also can have the invariant mass of constant thickness or have the invariant mass of variable thickness.The localized variation response characteristic of quality layers coupling vibrational structure preferably is particularly when the varied in thickness of quality.

For the coupling that the variation that helps vibrational structure responds, quality layers also can disperse along the axial direction of device.

In another embodiment, active elastic layers comprises and adheres to the plastic sheet on every side so that prevent the axial motion of active elastic layers.

Therefore, can be mechanically or tuning electrically DAVA to reduce harmful vibration and/or sound.Ground floor is made and is allowed the motion of the second layer made by dense material by the active material with low rigidity.Layer can be the multilayer with a plurality of resonance frequencys, or a plurality of discrete layer, and this layer is designed to change globally the distribution of kinetic energy.In addition, DAVA of the present invention controls vibration on the whole or large tracts of land at vibrational structure on a plurality of frequencies, and can be actuated electrically.

In another preferred embodiment, the invention provides the vibration isolator that is used for control vibration and sound radiation on the elongated area of vibrational structure, comprise: the matrix of at least two quality, wherein quality is relevant with distributed flexible member (for example polyvinylidene fluoride, piezoelectric ceramic, metal, polymer and electromechanical assembly etc.), and distributed flexible member is correspondingly distributed along the area of vibrational structure; And respective quality and the described vibrational structure relevant with corresponding distributed flexible member are spaced apart.

In another preferred embodiment, the invention provides and make vibration isolator ground method, comprise step at least: in the time will using vibration isolator to absorb vibration, determine pending frequency; (b) a plurality of quality (for example quality has weight in about 6 to 8 gram scopes etc. individually) is placed on the cover layer (cover layer of making by solid material for example; The cover layer of making by layer etc.) in at least one quality that is placed on specified location in the layer the uneven degree of depth and/or uneven quality and quality interval sentence with this cover layer absorber be tuned to the determined frequency of step (a).Randomly, the quality useful binders is inserted cover layer.Randomly, quality is mechanically inserted cover layer.Make in the preferred embodiment of inventive method of vibration isolator in practice, the weight that comprises the vibration isolator that quality is shaped is in 300 to 400 per 16 square inches scopes.In making vibration isolator, cover layer can comprise the quality of various sizes, various weight.

In another embodiment, vibration isolator is made of the three-dimensional foam material, and is included in and is distributed in appointed positions on the three-dimensional foam material X-Y size and along the z distribution of sizes of this three-dimensional foam material quality at the degree of depth place of appointment.The degree of depth of these appointed positions and appointment and the physics of described foamed material or chemical attribute allow the vibration damping at the assigned frequency place.This three-dimensional foam material can be made of a plurality of froth beds.Quality can be distributed in different layers and go up (this is similar with different designated depth along the z size).Quality can be inserted the opening in the three-dimensional foam material, covers with cladding material then.Optionally, if the opening in the three-dimensional foam material is to be form with the slit, slit can seal on the top of quality and the covering that need not to add (under any circumstance, should be understood that qualitative lid is optional and be the problem of design alternative).Although following discussion in a side upper shed of foamed material, it should be understood that opening can be formed on the offside of foamed material.The selection of quality can comprise metal (lead, iron and steel etc.) and nonmetallic materials (gelinite, liquid or fiber etc.) widely.

Description of drawings

With reference to the accompanying drawings, will understand above-mentioned better and other target, aspect and advantage by the following detailed description of the preferred embodiments of the invention, wherein:

Fig. 1 demonstrates the schematic diagram of the distributed active damper (DAVA) of first embodiment of the invention;

Fig. 2 demonstrates the motion of the active elastic layers of DAVA under the electric excitation effect;

Fig. 3 demonstrates the motion of the active elastic layers of DAVA under the mechanical excitation effect;

Fig. 4 demonstrates the schematic diagram of connection of the electrode of DAVA;

Fig. 5 demonstrates the experimental rig that is used to measure DAVA and the performance of some absorber contrast;

Fig. 6 demonstrate have 100 gram weight 6 " distributed absorber (non-active), the result of experimental rig among Fig. 5 of the some absorber of 100 grammes per square metres and the distributed mass layer of 100 gram weight;

Fig. 7 demonstrates result's the representative chart of the simulator of Fig. 5;

Fig. 8 demonstrates and uses DAVA of the present invention to carry out the ACTIVE CONTROL test;

Fig. 9 demonstrates the controller that uses in mode of the present invention and the layout of testing stand;

Figure 10 demonstrates the result of the ACTIVE CONTROL test with constant-quality distribution DAVA;

Figure 11 demonstrates the DAVA with optimum variation mass distribution; And

Figure 12 demonstrates the cutaway view of vibration isolator, and this vibration isolator has the quality layers of the quality of variable thickness;

Figure 13 demonstrates the cutaway view of vibration isolator, and this vibration isolator has the quality layers (be not as shown in figure 12 integral body) of discrete mass, and has the quality at the different-thickness at diverse location place;

Figure 14 demonstrates the DAVA with porous quality layers, this DAVA allows rattle or other vibration input on a side of this DAVA and the inverted configuration of bearing damping to run through elastic layer, and use the combination of elastic layer and quality layers to come damping, in addition, can use the structure of Figure 14 to reduce harmful acoustic radiation from the top quality layers;

Figure 15 demonstrates the cross section that has the vibration isolator of different size and difform discrete mass in different quality layers;

Figure 16 demonstrates by the quality layers that comprises that the active that is arranged in ducted PVDF or elastomeric material or passive spring layer support;

Figure 17 demonstrates according to exemplary heterogeneous tectal cutaway view of the present invention (seeing example I);

Figure 17 A demonstrates the guide wire of alternative shape of Figure 17;

Figure 18 demonstrates the tectal cutaway view (seeing example II) of invention;

Figure 19 and 19A demonstrate the tectal cutaway view (seeing example III) of invention;

Figure 20 demonstrates the tectal various examples (seeing example IV) of invention;

Figure 21 a-c demonstrates the end view of exemplary materials; This exemplary materials has the quality of embedding within it, and has at least one wavy, or jagged surface that coincide with certain body profile phase; And

Figure 22 a-b demonstrates the tectal side view of section of HG, and this HG cover layer comprises the thin quality layers of embedding and the HG quality of embedding.

Embodiment

The exemplary distributed active damper (DAVA) of the present invention preferably is limited to the quality that can be used in the structure of damping under oscillating action.Typically, the weight of DAVA of the present invention is no more than 10% of this structure gross mass; But the weight of DAVA can be more than 10% of the oeverall quality of this structure in application.Thereby have good attitude contribution ground, latent formula ground area for having main motion, the quality expection of comparing DAVA with the area with small motion is bigger.In addition, if the approaching driving frequency of disturbing of the local resonance of distributed absorber in this area, then the efficient of DAVA is higher.For other area, resonance frequency can be higher or lower than the frequency of this excitation.Partly, DAVA has and the known roughly the same resonance frequency of some absorber, make that the quality of local allocation is the sub-fraction of gross mass, and local stiffness is the sub-fraction of overall rigidity for this reason.The present invention ground DAVA is a distributed system, and this distributed system is controlled vibration in a plurality of frequencies on the whole or main area in vibrational structure ground, and preferably in some applications, can actuate electrically.

Fig. 1 demonstrates the schematic diagram of the distributed active damper (DAVA) of first embodiment of the invention.In this preferred embodiment, double layer design is adopted in design of the present invention.Ground floor 14 is the active elastic layers with low rigidity unit are that can electricity activation, and preferably has the polyvinylidene fluoride (PVDF) of 10 μ m thickness.Ground floor 14 can also be piezoelectric ceramic, piezoelectric transition (PZT) rubber (PZT rubber), metal, electromechanical assembly etc.Active elastic layers 14 can also be the elastomeric material by dotted line 15 signs (for example foam) as the electric actuator with embedding (for example layer 14).Can use almost any material, for example acoustic foam, rubber, polyurethane, acoustics glass fibre, and electric actuator can be PVDE, PZT rubber, metal (metal with elastic force identical with the quality of for example spring steel), polymer (having the elasticity identical with the quality of for example plastics or the polymer of elastic force), piezoelectric ceramic or other electromechanical assembly.

After this running through whole specification and will use active elastic layers 14 for illustrative purpose.But, be understood that fully that well-known any material mentioned above can similarly be used the invention process with other material or multilayer material in the vibration control field.In addition, identical Reference numeral will be used for identical composition in running through the remainder of specification.

Still with reference to figure 1, active elastic layers 14 is that preferred crooked (for example corrugated) is with amplitude that increases motion and the rigidity that reduces system.In a preferred embodiment of the invention, active elastic layers 14 in light weight and anti-bendings, and preferably have the design performance identical with corrugated cardboard.The second layer 16 is the distributed mass layer (for example absorbed layer) that can have constant thickness and be made up of rolled lead.But what fully understand is when putting into practice when of the present invention, the mass distribution of quality layers 16 can be included in the quality layers 16 along the variable-quality or the discrete mass of the whole or main area of structure 12 overall shapes, and can use other suitable light sheet material, for example iron and steel, aluminium, lead, composite glass fiber material etc.In the embodiment that uses variable-quality to distribute, variable-quality distributes will change the local attribute of DAVA to mate the locally variable response characteristic of foundation structure ideally.What also will fully understand is the two layer system that DAVA is not limited to active elastic layers and quality layers, but can be to use the multilayer system of inventive concept described here, for example have one deck active elastic layers at least and three layers of one deck quality layers or at least more than three layers system.

Quality layers 16 is designed to have 10% weight of structure 12, and the thickness of quality layers 16 directly depends on the weight of structure 12 per unit areas.For example, for girder steel or sheet, ignore the weight of active elastic layers 14, evenly the maximum ga(u)ge of lead layer can easily be calculated as follows:

h _m/h _p＝(ρ _b/ρ _m)*10％＝78000/11300*10％＝7％

Therefore, for the girder steel of 6.35mm, the maximum ga(u)ge of DAVA quality layers 16 of the present invention is 0.44mm.Whole or the main area on this supposition DAVA covered structure 12 (for example beams) surface.Under the situation of this weight limits, active elastic layers 14, for example crooked PVDF layer should have low-down rigidity.This control to low frequency is especially correct.For example, under the situation of the thick quality layers 16 (making) of 1mm, for the rigidity of the thick active elastic layers 14 of the resonance frequency 2mm that obtains 1000Hz is 9e+5N/m by lead.But such as previously discussed, DAVA can be in control vibration on the whole area of vibrational structure or main area on a plurality of frequencies.

As concise and to the point discussion, what also will fully understand is the multilayer that can comprise active elastic layers 14 and quality layers 16.By example, two-layer at least active elastic layers 14 is optionally stacked with two-layer at least quality layers 16.In a further embodiment, in order to control the different frequency of vibrational structure, every layer of active elastic layers 14 can be tuning individually, and every layer of quality layers 16 can have different quality.Certainly, embodiments of the invention are not limited to above-mentioned exemplary embodiment, and can similarly comprise active elastic layers 14 (being suitable for controlling different frequency) more or less and comprise more or less quality layers 16 (having different quality).

Preferably, at actuator, for example on each side of active elastic layers 14 thin layer as the silver of electrode 15.When voltage is applied between these electrodes 17 (these electrodes 17 can be placed on the active elastic layers Anywhere, preferably are placed on the offside of active elastic layers), in active elastic layers 14, produce electric field.The piezoelectric that active elastic layers 14 is preferably mechanically shunk and expanded under electric field effects.

Fig. 2 demonstrates the motion of the active elastic layers 14 under the electric excitation effect.Fig. 2 optionally 14 usefulness epoxy resin of the active elastic layers shown in the presentation graphs 1 is glued on the sheet plastic 18 and the point of active elastic layers 14 contact structures 12 and quality layers 16 (this quality layers 16 can be plumbous or other suitable material).Two layers of plastic 18 in active elastic layers 14 both sides prevents any axial motion.Line 30 be illustrated in the position of active elastic layers 14 in the inactive state and line 32 expressions when applying-active elastic layers 14 during V.In addition, line 34 expression is when applying+active elastic layers 14 during V.As clearly seeing from Fig. 2, the length of this active elastic layers 14 changes when voltage is applied on the active elastic layers 14, the result, and the distance between two planes of each side of quality layers 16 changes.The design of DAVA will be moved outside the plane that is transformed into active elastic layers 14 of moving in the plane of active elastic layers 14.The shape that Fig. 2 has enlarged active elastic layers 14 crooked mode under different stress tectonisms, and in fact the motion of active elastic layers 14 is small and therefore be presumed to linear.

For analyzing for simplicity, be understood that wavy member, for example active elastic layers 14 (see figure 1)s constitute a plurality of springs.In a single day these springs easily are compressed under the situation that does not have quality 16, but apply quality 16, they just are not easy to be compressed.In addition, in case the quality 16 that applies be distributed in then on a plurality of springs.

Fig. 3 demonstrates the motion of the active elastic layers under the mechanical excitation effect.In particular, line 40 is illustrated in the active elastic layers 14 in the inactive state, and the active elastic layers 14 of line 42 expressions when negative load is applied on the active elastic layers 14.In addition, the active elastic layers 14 of line 44 expressions when positive load is applied on the active elastic layers 14.When DAVA was subjected to the mechanical force constraint, the length of active elastic layers 14 did not change; But, the alteration of form of active elastic layers 14.It is to be noted owing to ignoring the shearing of quality layers 16, so in emulation, do not consider the bending rigidity of quality layers 16.

Be pointed out that the rigidity on the unit are is low, still, whole DAVA is distributed in the rigidity height on the vibrational structure elongated area with having importance.Also importantly be pointed out that DAVA rigidity (and quality) thereby and resonance frequency can be depending on the specific application adjustment of DAVA; But bending rigidity depends on the space wavelength and the amplitude of the wavy part of active elastic layers 14, makes that bigger wavelength reduces bending rigidity along normal direction.It should be appreciated that DAVA bending rigidity vertically is very high, and preferably be similar to honeycomb.In addition, the lateral stiffness of DAVA is partly little, and DAVA has and the identical rigidity of some absorber with similar quality globally.Although the therefore independent sheet softness very of active elastic layers 14, the very anti-globally extruding of DAVA.

Thereby the lateral stiffness of active elastic layers 14 and resonance frequency can be by height, the wavelength of wavy active elastic layers 14, the thickness of active elastic layers 14 and the electric shunt adjustment between active elastic layers 14 electrodes of active elastic layers 14.Particularly, the thickness of increase active elastic layers 14 just reduces the lateral stiffness of DAVA.In order to make device consistent with the elongated area of (as among the present invention) vibrational structure, this thickness can not increase very many.Second wavelength that parameter is an active elastic layers 14 can revising makes bigger wavelength reduce the lateral stiffness of active elastic layers 14.Because wavelength is compared with the wavelength of disturbance and should be kept lessly, so the variation of this parameter also is limited, otherwise the DAVA feasible solution removes its distributed nature.

The thickness of active elastic layers 14 is another parameters that can adjust for the rigidity that influences DAVA.For example, active elastic layers 14 is thin more, and the rigidity of active elastic layers 14 is low more.The final solution of revising the lateral stiffness of active elastic layers 14 is to use the piezoelectric property of active elastic layers 14.For example, electric shunt can provide the minor alteration of rigidity in the active elastic layers 14.Therefore, when when active elastic layers 14 provides effective input, its mechanical stiffness is less or equally turn round greatly seemingly just can to control active elastic layers 14.

DAVA can prepare by cutting these sheets along PVDF sheet or above-mentioned other principal direction of similar (PVDF has the bigger direction of strain under the effect of effectively excitation, and this direction is the principal oscillation direction of absorber and foundation structure).Then, preferably remove 1 to 2mm silver electrode at the edge of PVDF sheet.In a preferred embodiment, acetone is the extraordinary solvent that is used to remove silver electrode 17.The 3rd step was that the connector that is connected to each electrode 17 is installed.Fig. 4 demonstrates the schematic diagram of the connection of DAVA electrode.Particularly, be chosen in two areas of active elastic layers 14 1 ends with a bucking a rivet 22.These areas should a side at them have electrode 17.Removing an electrode 17 from each area makes 20 in rivet contact an electrode 17.The hole that diameter is slightly smaller than rivet 20 cuts in these areas, and the welded top of each rivet 20 makes lead 22 can use riveting pliers correctly to locate to lead 22.In an embodiment, can be placed on the back side of active elastic layers 14 for the extra block that firmer connection plastics 24 are provided.Use riveting pliers known in the art that rivet 20 is placed in the rivet hole then.The additive wire (not shown) is connected to other electrode, and two guiding are welded to electric connector then.Because very high voltage can drive the PVDF active part of DAVA, be important so set up the precision that this connection has.Those skilled in the art should be understood that the electrical connection that can use many other forms in practical framework of the present invention.

The given structure for the treatment of the vibration of damping can make active elastic layers become the wavy of appropriate size.This can be with accomplished in many ways.A kind of preferable methods imagination is arranged on PVDF between one group of calibration survey fibre and with PVDF and is maintained fixed the time in place several days.The plastic sheet (not shown) can be attached to the either side (top or the end) of PVDF so that PVDF is adhered to the structure that damping is treated in vibration, and quality is adhered to PVDF (for example glue or other suitable jointing material can be coated on this sheet equably) after plastic sheet is fixed to wavy texture.In addition, plastic sheet can be used for flexibly PVDF is isolated from vibrational structure and/or the quality that applies.In addition, wavy PVDF can be positioned in foam or other elastomeric material.This can be inserted in the elastomeric material by deposition elastomeric material on the surface of PVDF or with PVDF and realize.As above explanation is such, also can use optional material (for example metal, piezoelectric ceramic etc.) to replace PVDF.PVDF also fully bending make ripple encirclement itself so that form to support the tubular structure of quality.In some passive application, other materials such as plastics or spring steel can be used in and constitute as the pipeline in the waved spring layer.

Fig. 5 demonstrates the experimental rig that is used to measure DAVA and the performance of some absorber contrast.This identical test is also at the tuning of emulation and checking.It is 0 to 1600Hz white noise signal that noisemaker 40 provides frequency band.This signal is exaggerated at amplifier 44 places and then by boost in voltage transformer 44.The output of transformer 44 is used to drive PZT, and this PZT actuates brace summer then.The normal velocity that laser velocimeter 46 is measured along beam, and the output of this laser velocimeter is obtained by data acquisition system 48 (for example personal computer, capture card and relevant software).Personal computer 50 is used for the reprocessing data then.

Fig. 6 represents the mean square velocity of beam.These data are relevant with the mean kinetic energy of beam, and by calculating to every square speed summation and divided by count (for example 23).Mean square velocity is with every volt excitation normalization, and appearance is from 100Hz to 1600Hz.This frequency band is not included in the beam of first pattern at 40Hz place.Fig. 6 except line 50 wired have equal in quality vibration control system of (for example local and distributed absorber have 100g) of demonstrating.The independent measurement of line 50 expression beams makes it possible to observe in turn second to the 6th pattern of beam.Line 52 expression has the state of beam of the some absorber of 100g.The resonance frequency of this absorber is 850Hz, and influential to the 5th pattern.This mode abruption becomes to have two resonance than small leak.Attention: although the some absorber reduces vibration at its attachment point, in fact the some absorber increases the mean square velocity of beam.By tuning (resonance frequency of absorber is at 1000Hz) preferably, these peak values will be the center to the right of axis motion and with 1000Hz.Line 54 expressions have the state of the beam of DAVA.In this test, DAVA is as passive device.Can notice that the decay that is provided by DAVA is different from an absorber.Provide the overall situation decay of the beam vibration better at nearly all frequency DAVA, especially at mode resonance crest place than an absorber.Similarly structure is presented in the simulation configurations of Fig. 7.The line 50,52,54 of Fig. 6 is identical with the line 50,52,54 of Fig. 7.Also realized tangible minimizing for the 3rd, the 4th and the 6th pattern.Attention: put absorber by contrast and realized very little minimizing.In resonance frequency, only show small change and only increase a little damping by the additional mass of the line among the line among Fig. 6 55 and Fig. 7 55 indication.The distributed mass of identical weight does not provide the almost vibration attenuation of as much with DAVA.So as can seeing, DAVA works by using dynamic effect (active force), controlling beam vibration, but on distribution area in the conceptive mode that is similar to an absorber, its new can improvement thus.

The emulation of Fig. 6 and Fig. 7 clearly shows two types absorber, for example puts the difference between absorber and the DAVA of the present invention.For example, the some absorber single-frequency and the independent point of vibrational structure be in reduce in the response very effective.Energy only moves to different frequency bands and produces two new resonance.But DAVA is this defective not, and all square vibrational energy of beam reduces for all resonance frequencys of beam and any new resonance can not occur.Therefore, DAVA can control several patterns in different frequencies with diving formula simultaneously.For example the damping of plate is very useful for the mode compact structure for this characteristic.

Fig. 8 demonstrates the ACTIVE CONTROL test of using illustrative DAVA of the present invention to carry out.Control system is used three accelerometers 60, band pass filter 64 and feedforward LMS (lowest mean square) controller 62 (the realizing) as error pick-up on DSP (Digital Signal Processing) plate.Vibration measurement is carried out with laser velocimeter 46 once more.Disturb still the white noise that produces by the identical DSP that is used to realize controller 62.Controller 62 makes error pick-up signal minimum by the beam attempt that control has the DAVA active part.The all input and output of controller are filtered with band pass filter 64.In order to make the error signal minimum under the situation of known one group of input, control algolithm is well-known and make one group of optimized LMS algorithm of N sef-adapting filter in the vibration control field.Algorithm can be used in modeling linear system.Gradient method is used to find N the optimum weight that past value is relevant with system's input.The error signal that is used for gradient search is the true output of system and the difference between the sef-adapting filter output.

Fig. 9 demonstrates the controller of test DAVA performance and the layout of testing stand.In this test, interference signal is still filtered as reference signal and by the DAVA of Fig. 8 and the estimation of the transfer function between each error pick-up (accelerometer) 60.These transfer functions are obtained by the system identification of using the LMS algorithm, and the active input on the controller software use DAVA makes the vibration minimum in the error pick-up position.The parameter of this ACTIVE CONTROL test is presented in the table 1.

Table 1

Error pick-up	3
Error pick-up	3	The active absorption device	1
Disturb	The PZT sheet	The active absorption device	1
Disturb	The PZT sheet	Benchmark	Inner
Sample frequency	5000Hz	Benchmark	Inner
Sample frequency	5000Hz	The system identifier filter coefficient	120
Control path filters coefficient	180	The system identifier filter coefficient	120

Table 1: the parameter that is used for ACTIVE CONTROL

Error pick-up 60 is positioned at the center-7.5 apart from beam respectively " ,-1.5 " and 5.5 " locate.Use laser velocimeter that per inch beam (for example whole 23 points) is carried out vibration measurement.

Mean square velocity is by to square summation of the velocity amplitude of every bit response and average and start at.Therefore the whole energy that vibrate in mean square velocity and this beam are proportional and be presented among Figure 10.Particularly, Figure 10 demonstrates the have DAVA of the present invention ACTIVE CONTROL test of (constant mass distribution).Line 70 is illustrated in the state that does not have device to be connected to this beam under the situation on the beam, and therefore expression is used for the baseline of comparison.Line 72 is illustrated in DAVA with connection and this DAVA state as this beam under the situation of passive device (just not applying control signal).The result of passive DAVA demonstrates the good decay at all whole beam energy in resonance frequency place.The frequency band that reduces 100 to 1600Hz of the mean square velocity that obtains in this passive structure is 10dB.Therefore two passive aspects of key of this presentation of results DAVA: spread all over the control of whole vibration of beam and side by side control in a plurality of frequencies.This should with typically only form contrast on one point and at the conventional point vibration isolator of single-frequency control vibration.Under the situation of ACTIVE CONTROL effect, obtain additional 3dB decay in mean square velocity.State by the beam of DAVA ACTIVE CONTROL is presented by line 74.The active system performance reduce aspect the resonance peak very good, for example, the minimizing of most important crest 600Hz place acquisition 20dB before control.Between resonating, ACTIVE CONTROL strengthens vibration (being called the control leakage), and this can be easily by using controller and more error pick-up correction preferably.Under the situation of ACTIVE CONTROL effect, this structure does not have resonance state, and DAVA increases tangible damping to system.Because the response of PVDF and absorber itself, so below 400Hz, there is not initiatively control.Other is composition initiatively, and for example electromagnetic actuators will reduce this operation active frequency.

In order to improve the efficient of DAVA, make the mass distribution optimization.That is to say, for the decay of enhancing is provided, quality layers 16 will be preferably along the length variations of the whole or main area of beam.The mass distribution that changes will change the local characteristics of DAVA to mate the localized variation response characteristic of foundation structure ideally.But, because beam/DAVA response is complicated along this beam, so need to derive the optimal process that is used to select mass distribution sometimes.

Figure 11 demonstrates the DAVA with optimum variation mass distribution.Mark on the every part of the DAVA top refers to the polarity of elasticity PVDF sheet 14 with respect to piezoelectric driving plate (interference).Attention: interference position is depended in the response of the beam that uses in the optimizing process consumingly, and the maximum idle dynamic effect of DAVA appears at and disturbs opposite direction.Can change the thickness of quality layers 16, quality remains unchanged simultaneously.Quality changes can be as continuous component or in zone of dispersion as shown in figure 11.

In another structure, can use to have a plurality of quality resonant layers that change mass property.Figure 12 demonstrates has a layout that embeds as this system of the two-layer resonance mass layer 150 of the foam of spring material 154 and 152.Be appreciated that quality layers can be continuous or in zone of dispersion.This device has the advantage of two resonance, and therefore has the wider frequency range of vibration control.Figure 12 demonstrates in the thin position of quality layers 152 has the quality layers 150 of bigger thickness.Quality layers 150 or 152 thickness that change will provide the vibration isolator with different resonance characteristicss, and quality layers 150 relative to each other can allow simultaneously at two different resonance along the thickness of Z axle in the variation of identical relative position with 152.

In another structure shown in Figure 13, quality layers 160 for example is positioned at the different degree of depth in the foam with 162 divisions and at spring material 166.The different degree of depth changes the rigidity of the spring material that supports each quality.Because a plurality of degree of depth and so a plurality of spring rate that quality embeds are so this layout causes a plurality of resonance frequencys of this device.A plurality of resonance frequencys cause the broadband of this device non-constant width on effective frequency.Attention: the discrete mass of embedding can have any common shape.Except the above-mentioned different materials that can be used for spring system (for example rubber, glass fibre cotton-wool, spring metal, polyurethane etc.), Figure 13 demonstrates and can use many different quality layers, quality layers can be (segmentation just) of dispersing, and quality layers can have the fragment of different-thickness.These layers 160,162 and 164 can be made in a controlled manner with tuning in the specified frequency appointed positions, but more preferably, thereby can be applied to the vibration absorber that obtains to be suitable for a plurality of resonance frequencys in the random fashion.In addition, device shown in Figure 13 can use in active discussed below and passive vibration control system.

In the variant on Figure 12 and 13 illustrated embodiments, can be with the active composition, for example piezopolymer and pottery and electromagnetic actuators embed in the spring material applying active force, thereby change the motion of mass component.This device will have the performance of improvement when the electrical control method with previous discussion uses.Especially, the ACTIVE CONTROL that combines with the quality of variation of the inherent one or more height of elastic layer will be considered the vibration damping of obvious improvement in many application.

Figure 14 demonstrates quality layers 170 another embodiment by the device of porous material (for example porous lead or iron and steel or the like) formation.By this layout, vibration isolator also can absorb and be easy to pass through the sound wave that eyelet 174 is propagated on the surface of vibration isolator, and the vibration that is controlled at the foundation structure under the elastomeric material 174.This embodiment prevent quality layers 170 effect just as sound source (in some applications just, " layer " of quality integral body future the self-damping structure the audible signal that elastomeric material disperses of passing through be transferred to external environment).In addition, except by resistance of shock absorber from the structural vibrations (elastic layer 174 below), the vibration of the environment that comes from the outside or audible signal also can be by eyelets and by resistance of shock absorber.Such as discussed above in conjunction with Figure 12 and 13, the structure of Figure 14 can with initiatively and the mode of passive device use that (aggressive device is to comprise that the PVDF of embedding or piezoelectric ceramic or other are applying the material that can expand or shrink under the voltage effect; Passive device comprises quality layers 172 and elastomeric material 174 spring material (for example metal etc.) of embedding (but also can have) simply).In addition, the structure of Figure 14 also can the discrete mass in place, one or more plane and embedding in elastomeric material shown in Figure 13 and 15 be used in combination, and discrete mass can change aspect size, shape and the weight.

Figure 15 demonstrates the discrete mass layer 180 that has embedding in

elastomeric material

184 and 182 vibration isolator.Figure 15 illustrates the use of the quality of different size and shape.These can distribute randomly to realize the broadband damping of resonance frequency, perhaps they with the pattern of regulation apply with the frequency response of ad-hoc location in the vibration isolator be tuned to specific frequency.Some quality can be the spheroid of ball type, and other can be flat thin rectangle simultaneously.The shape of quality will be to influence the response to different vibration frequencies as the desired controllable distinct methods of producer.

The vibration isolator that Figure 12 to 15 demonstrates can be by the multiple technologies manufacturing, and be coated with one deck foam wherein the simplest comprising, one or the discrete quality of deposition one deck, and foam and quality layers process several times are repeated in the back.Optionally, quality layers can embed in the elastomeric material during the making of elastomeric material.Optionally, can embed elastomeric material via this otch at selected position cutting elastic material and mass fragment.In case embed, the elasticity of material keeps quality in position and closure of incisions.

Figure 16 demonstrates DAVA or vibration isolator, and wherein the drive spring layer is made of the pipeline 190 of PVDF or plastic-like material etc., is respectively applied for initiatively or passive application.Because tubular form is the complete extension of crooked wave shape and keeps curvature along the plane of absorber, so electric excitation will think that also quality provides normal direction initiatively to import.But by this tubular structure, the size of the damping of the caused DAVA of viscous loss of fluid that provides owing to pump into and pump pipeline or vibration isolator can more easily be adjusted and be had to the diameter of pipeline.

(this vibration isolator comprises the matrix of at least two kinds of quality to the vibration isolator of invention, and wherein quality is relevant with distributed flexible member, and distributed flexible member is respectively along the area distributions of vibrational structure; And respective quality and the described vibrational structure relevant with corresponding distributed flexible member are spaced apart) can randomly comprise elastomeric material (for example acoustic foam, acoustics glass fibre, glass fibre cotton-wool, distributed spring material, polyurethane, rubber etc.), this elastomeric material has the distributed flexible member that is embedded in the described elastomeric material.The example of vibration isolator of invention be for example be included as rubber elastomeric material and for the vibration isolator and the wherein said elastomeric material of the distributed flexible member of polyvinylidene fluoride be that solid polyurethane and described flexible member are the vibration isolator of the elastomeric material of polyvinylidene fluoride.The vibration isolator of invention can randomly comprise the distributed flexible member that has waveform along at least one size.

In the vibration isolator of invention, quality can adhere on the surface of the distributed flexible member that uses in the vibration isolator.The quality of using in the vibration isolator of invention can randomly be made up of distributed discrete mass fragment.Use in vibration isolator under the situation of two discrete mass fragments, in the optional described discrete mass fragment at least two relative to each other randomly different aspect at least one in size, shape and thickness.In the vibration isolator that uses discrete mass fragment and elastomeric material, the discrete mass fragment can embed in the elastomeric material, and for example the discrete mass fragment embeds in two interior Different Plane of elastomeric material at least.In the vibration isolator that uses discrete mass fragment and elastomeric material, the discrete mass fragment can be included in lip-deep at least one mass fragment of elastomeric material and embed another interior mass fragment of elastomeric material.In the vibration isolator that uses two discrete mass fragments and elastomeric material, these two discrete mass fragments can embed elastomeric material on different planes.In the vibration isolator that uses two discrete mass fragments and elastomeric material, the first discrete mass fragment can appear on the surface of elastomeric material, and the second discrete mass fragment can embed in the elastomeric material.

The distributed flexible member that uses in the vibration isolator can comprise one or more tube elements.Tube element can be by formations such as for example polyvinylidene fluoride (PVDF), metal, plastics.

The quality of using in the vibration isolator can be perforated.For example, eyelet is included in the quality in the mode that the eyelet amount in the quality is enough to reduce or eliminate the acoustic vibration of dispersing from described quality layers top; Be included in the quality by the mode that described quality layers runs through described distributed flexible member be enough to allow the to come from the outside sound of environment of the eyelet amount in the quality; Or the like.

The quality of using in the vibration isolator can be made up of metal (for example lead, steel etc.), plastics, pottery, glass, fiber quality, carbon, solid, gelinite, fiber etc.When using more than a kind of quality, for example in matrix, use two or more quality, these quality can be identical or different.

The exemplary configurations of the vibration isolator that is used to invent is the structure that comprises the matrix of a plurality of quality, for example comprises the matrix of quality of the regular shape of one or more geometry; The matrix that comprises one or more erose quality; Be included in different quality and place the degree of depth and/or the different quality and the matrix of quality interval.

In order to understand the other example of explanation below the present invention better, but the invention is not restricted to these examples.

Below with reference to example, heterogeneous (HG) cover layer of the invention that is used for the control of vibration control harmony is discussed.

The cover layer of example I to IV invention can use in any application of using sound dampening or shock material.Existing melamine/polyurethane foam that the cover layer of invention can replace using in commercial or industrial noise control (wherein acoustic foam is used as absorbent material individually to reduce radiation and repercussion) traditionally uses.

Advantageously, the HG cover layer of example invention is used for a plurality of purposes, includes but not limited to: reduce the structure transmitting vibrations, loss is provided and reduces repercussion.

In another embodiment of the present invention, the HG cover layer is made of elastomeric material, and this elastomeric material has in different positions at least two quality and one or more continuous thin-material layers that embed elastomeric material in the different degree of depth that embeds this material with the degree of depth.The continuous material layer can be selected from following material system, for example soft quality fence (limp mass barrier), thin elastic metal sheet, thin polymer plate or their combination.Should can punish into section in the length in cycle by thin non-individual body, but these length are longer than the thickness of this pantostrat.In this embodiment, this embodiment can construct to be suspended at unbraced structure and freely hang the HG cover layer in the space.So the quality of this embedding works to improve its sound transmission loss to the thin layer that embeds.We after tested these have the layout of good result.Existing sound dampening or vibration damping structure need the structure (as airframe) of connection.Therefore by this open standard form (freestandard version) of this embodiment imagination with this structural engagement to wherein.

Example I

With reference to Figure 17 and 17A, the HG cover layer of this example I comprises the froth bed 171,172,173 and 174 of the quality 179 with the one or more tops that are positioned at each layer.(in Figure 17 and 17A, demonstrate four layers, but be understood that according to using in the cover layer of the present invention than four layers of number of plies more or less.) layer 171,172,173 and 174 is by bonding method or reagent, for example gluing, foaming foams etc. are bonded to each other.Layer 171,172,173 and 174 can have identical or different thickness.Layer 171,172,173 and 174 has appointed thickness and the quantity relevant with the degree of depth of quality 179.In each of layer 171,172,173 and 174, can use identical or different foamed material.Different sound-absorbing materials, for example the glass fibre cotton-wool can replace in layer 171,172,173 and 174 using one or more in foam use.

The interfacial adhesion agent can be used for example interfacial adhesion agent 178 between the layer 172 and 171.The foam at reference point 177 places, foam can be on whole surface fully contact quality 179 or partly contact quality 179.

Example II

With reference to Figure 18, in example II, the HG cover layer comprises the quality 189 that is positioned at designated depth and position.Consider the rigidity of material 181 (for example foam, glass fibre cotton-wool etc.) and the weight of quality 189, the quality 189 that the degree of depth that quality is placed just embeds is designed to target frequency resonance and determines.The position based target model shape that quality 189 is placed is determined.Measure or calculate the rigidity (for example foam stiffness) of material 181.

The degree of depth of quality 189 is determined the resonance frequency of quality 189.The model shape of the definite structure that will control in position.For the cover layer of design, for the quality 189 of a plurality of embeddings is specified the one group of position and the degree of depth.

Example III

With reference to Figure 19 and 19A, in this example III, the HG cover layer of invention comprises sound-absorbing material layer 191 (for example foam, glass fibre cotton-wool etc.), and this sound-absorbing material 191 has the quality 199 that is arranged in from the hole 192 of foam coring.The stopper of being made by sound-absorbing material (for example foam, glass fibre cotton-wool etc.) 193 is placed in the core so that quality 199 is kept in position then.Bonding method, for example gluing, foaming foam etc. is used for maintenance in position.Figure 19 A demonstrates by the hole 192 of removing core; Insert quality 199; With insertion stopper 193 and with the stopper 193 fixing HG cover layers of finishing 1999 that form in position.Figure 19 demonstrates in the cover layer of finishing 1999 of shop drawings 19A than step early.

In optional method, sound-absorbing material 191 (for example foam, glass fibre cotton-wool etc.) is cut slit and quality and is inserted in the slit to the degree of depth (just not needing stopper) that needs.Joint method is for example gluing, and foaming foam etc. is used to seal slit and quality is kept in position.

Example IV

With reference to Figure 20, the HG cover layer of invention can comprise circle, bent segments, rectangle and the box-shaped HG cover layer as limiting examples.Circular HG cover layer 200C comprises the quality 209 of embedding and sound-absorbing material 201 (for example foam etc.).Bent segments HG cover layer 200V comprises quality 209 and sound-absorbing material 201.Rectangle HG cover layer 200R comprises quality 209 and sound-absorbing material 201.The HG cover layer 200L in L shaped cross section comprises quality 209 and sound-absorbing material 201.The HG cover layer 200B of box section has hollow interior and comprises quality 209 and sound-absorbing material 201.

Example V

With reference to Figure 21, comprise that the HG cover layer of the invention of the quality 219 of embedding and sound-absorbing material 211 (for example foam, glass fibre cotton-wool etc.) can comprise difform surface, for example mentioned ridge-shaped, shaped form, waveform is linear and peak shape (for example unimodal or multimodal).The HG cover layer also can comprise example I to IV and combine with them.Surface 212 is examples of bending or waved surface.Surface 213 is examples of serrated-surface.Single wedge shape 214 is embodiment of wedge shape.

Example I to V is a limiting examples.Can design and construct the multiple matrix of the quality that comprises sound-absorbing material and embedding.Comprise that at structure different shape can be used for quality in the matrix of the effectiveness in vibration suppression that will have expection of sound-absorbing material and quality, for example sphere, disc, plate shape or other rule of how much or irregularly shaped.Quality can be identical shape or different shapes.Quality can be same size or different size, and can be identical weight or Different Weight.The example of material of structure quality is for example metal, plastics, pottery, glass, fiber quality, carbon or the like; Solid, gelinite, fiber or the like.Quality can be in sound-absorbing material and the degree of depth place that is placed on variation with the quality that changes and quality interval.

In the time will using vibration isolator the selection of quality and their weight, size and placement by at main frequency determine.Vibration isolator (for example HG cover layer) can be tuned to and show bigger loss and/or absorption in specific frequency or group of frequencies.The size of quality, shape and weight influence sound or vibration reaction.Because place quality group part " tuning " cover layer more or less in the specific degree of depth, so the placement of quality especially merits attention.The HG cover layer can also improve performance by near the quality basis material (sound-absorbing material just) edge in application-specific.

Vibration isolator (for example HG cover layer) can be made or be had the stratification ground, inclusion ground that is placed on certain location place in each layer and make by solid material.Layer can be gone up variation to satisfy the commercial geometry of using of expection at thickness and structure (for example square, circle, ellipse, rectangle etc.).The number of plies in specifying the HG cover layer depends on uses total admissible thickness and resonance frequency.The HG cover layer in layer or the shape that changes on the solid comprise, for example circular, crooked, rectangle, L shaped section and, box-shaped or the like.The number of plies is determined by the quantity of the quality of application, thickness, weight, frequency and/or needs insertion in the HG cover layer.The layer that is included in the HG cover layer can have the thickness of homogeneous thickness or variation according to required tuning process.Quality can enough adhesive or is mechanically inserted layered material or solid material.

The HG cover layer comprises use mechanical clamp or screw by any suitable method, and use glue or adhesive etc. can apply or be fixed to structure or the device that is used for vibration control.Tuning can finishing in advance according to above-mentioned technology, or can finish with eyesight via empirical method is for example by applying the HG cover layer or be fixed on structure or the device, then with quality (for example lead or weight metal; Viscosity inclusion body etc.) insert inherent diverse location of HG cover layer and/or differing heights (near or leave this device or structure) opening or the slit located.

Example VIII

Figure 22 a and 22b demonstrate the continuous or semi-continuous thin quality layers 400 and 400 ' that is arranged in foamed material 402.Foamed material 402 can be monolithic (thick individual layer) or the multilayer as above described in detail.Thin quality layers 400 and 400 ' can be any multiple different materials that comprises metal, plastics, thin elastic qualities etc.The major function of thin quality layers is for example to cross over the length and the width of foamed material along the X-Y size, and provides suitable rigidity to foamed material.The soft quality fence that only comprises the soft quality that is embedded in the foam before had been used to absorb low frequency audible signal and noise.But the present invention improves this device significantly by the inclusion of the quality 404 of the embedding that distributes along X-Y plane and Z axle on a plurality of surfaces in foamed material 402.What as above go through is such, and the quality 404 that a plurality of embeddings are set is used to adjust can be by the frequency of the device damping shown in Figure 22 a and the 22b.This is because the quality that embeds works with damping vibration (for example audible signal and noise) with continuous or semi-continuous quality layers 400 or 400 '.The quality 402 that graphical display goes out to embed is at offside continuous or semi-continuous quality 400 or 400 '; But, should be understood that the quality of embedding can be at a side or offside.For above-mentioned reasons, should be understood that since the utilization of the present invention quality that is attributable to embed with respect to the damping of spring/relationship between quality of quality layers 400 or 400 ', and consider continuous or half two quality layers of being permitted 400 or 400 ' that weight is very light, in Figure 22 a and 22b so the soft quality fence of imagining is lighter significantly than existing technology.Allow the material bending shown in Figure 22 b to become the user desired or use needed various structure in cutting apart of 405 places, space.

For example airframe is with respect to, material with being applied directly to vibrational structure, and for example the felted device shown in Figure 22 a and the 22b has ability self-support or that hang.For example, because soft quality layers 400 and 400 ' absorbs vibrational energy, then by the mode damping of the quality 404 that embeds with above detailed description, the sound or the noise that prevent tent inside or outside generation are thus propagated by material, make quiet or very quiet tent so the material shown in Figure 22 a and the 22b can be used in.Imagination also will be recognized many other application fully by among those skilled in the art, for example this material is placed on the inside of the door of car or other vehicle, place house interior (for example wall, from ceiling suspension etc.) to be used for the undesirable sound wave of damping this material, and many other application.

Example VII (prototype)

Use is used for different shape, weight, interval and the degree of depth of quality (inclusion) and has made prototype.Tested prototype.The inclusion of 6 to 8 grammes per square metres is used in most test, and the total weight that increases material is between/16 square feet of 300 and 400 grams.Test is in all frequencies, but especially at low frequency be higher than the decay that demonstrates improvement in the frequency of 100Hz.The layout of the variation of the inclusion of different size, layout and weight has shown that tuning is actual.Test is carried out on the HG cover layer, and this HG cover layer comprises multiple size and weight, places to strengthen the inclusion of sound absorbing capabilities in specific frequency strategicly.Therefore, inclusion (quality) can have at random or the unified shape of placing with pattern and weight or at random or the multiple shape and the weight of placing with pattern.

Demonstrated tectal purpose of the HG that comprises the matrix that embeds quality or use and be following one or more: reduce the structure transmitting vibrations, compare the loss (TL) that obvious enhancing is provided with independent matrix (acoustics) material and reduce repercussion.Can not increase significantly under the condition of material ground total weight, inclusion is not having to strengthen sound absorbing capabilities on the absorbent material of filler.Test has relatively verified that the material that does not have inclusion to be bonded together can not provide the performance of the enhancing with same material that inclusion is bonded together.

Although described the present invention according to a preferred embodiment of the invention, in the spirit and scope that person of skill in the art will appreciate that in claims, can put into practice the present invention with modification.

Claims

1. vibration isolator that is used on the elongated area of vibrational structure the control vibration and sound radiation, comprise: the matrix of at least two mass, the mass in wherein said at least two mass is relevant with the distributed flexible member of locating along the area of vibrational structure; And respective quality body and the described vibrational structure relevant with corresponding distributed flexible member are spaced apart.

2. vibration isolator as claimed in claim 1 also comprises elastomeric material, and described distributed flexible member embeds in the described elastomeric material.

3. vibration isolator as claimed in claim 2, wherein said elastomeric material is selected from the group that following material constitutes: acoustic foam, acoustics glass fibre, glass fibre cotton-wool, distributed spring material, polyurethane and rubber.

4. vibration isolator as claimed in claim 1, wherein said distributed flexible member is selected from the group that following material constitutes: polyvinylidene fluoride, piezoelectric ceramic, metal, polymer and electromechanical assembly.

5. vibration isolator as claimed in claim 2, wherein said elastomeric material is a rubber, and described distributed flexible member is a polyvinylidene fluoride.

6. vibration isolator as claimed in claim 2, wherein said elastomeric material is a solid polyurethane, and described distributed flexible member is a polyvinylidene fluoride.

7. vibration isolator as claimed in claim 2, wherein said elastomeric material are foam or distributed spring material, and described distributed flexible member is a polyvinylidene fluoride.

8. vibration isolator as claimed in claim 1, wherein said distributed flexible member has waveform shape along at least one size.

9. vibration isolator as claimed in claim 1 is on the surface of wherein said mass attached to described distributed flexible member.

10. vibration isolator as claimed in claim 1, wherein said mass is made up of distributed discrete mass fragment.

11. vibration isolator as claimed in claim 10, in the wherein said discrete mass fragment at least two relative to each other different in following at least one: in difference aspect the size; In the vpg connection difference and in difference aspect the thickness.

12. vibration isolator as claimed in claim 10, wherein said discrete mass fragment is embedded in the described elastomeric material.

13. vibration isolator as claimed in claim 10, wherein said discrete mass fragment embeds in the described elastomeric material at least two Different Plane.

14. vibration isolator as claimed in claim 10, wherein said discrete mass fragment are included in lip-deep at least one mass fragment of described elastomeric material and embed another interior mass fragment of described elastomeric material.

15. vibration isolator as claimed in claim 11, wherein said two discrete mass fragments embed in the described elastomeric material at different places, plane.

16. vibration isolator as claimed in claim 11, first in wherein said two discrete mass fragments is present on the described elastomeric material surface, and in second described elastomeric material of embedding in described two discrete mass fragments.

17. vibration isolator as claimed in claim 1, wherein said distributed flexible member comprises one or more tube elements.

18. vibration isolator as claimed in claim 17, wherein said one or more tube elements are made of polyvinylidene fluoride (PVDF).

19. vibration isolator as claimed in claim 17, wherein said one or more tube elements are made of the material of selecting from the group that metal and plastics are formed.

20. vibration isolator as claimed in claim 1, wherein said mass is a porous.

21. vibration isolator as claimed in claim 20, wherein said mass is made up of metal.

22. vibration isolator as claimed in claim 21, wherein said metal is selected from the group of plumbous and steel composition.

23. vibration isolator as claimed in claim 20, the amount of wherein said mass perforations are enough to reduce or eliminate the acoustic vibration of sending from described quality layers top.

24. vibration isolator as claimed in claim 20, the amount of wherein said mass perforations are enough to allow the sound from surrounding enviroment to extend through in the described distributed flexible member by described quality layers.

25. vibration isolator as claimed in claim 1 comprises the matrix of a plurality of mass.

26. vibration isolator as claimed in claim 25, wherein said matrix comprises the mass of one or more regular geometry.

27. vibration isolator as claimed in claim 25, wherein said matrix comprise one or more mass in irregular shape.

28. vibration isolator as claimed in claim 25, wherein said matrix comprise that the mass of different depth is arranged and/or different mass and mass intervals.

29. vibration isolator as claimed in claim 1, wherein said mass is selected from the group that following mass constitutes: metal, plastics, pottery, glass, fiber and carbon.

30. vibration isolator as claimed in claim 25, wherein said mass is selected from the group that following mass constitutes: metal, plastics, pottery, glass, fiber and carbon, and wherein said mass can be identical or different.

31. vibration isolator as claimed in claim 1, wherein said mass is selected from the group that following mass constitutes: solid, gelinite or fiber.

32. vibration isolator as claimed in claim 25, wherein said mass is selected from the group that following mass constitutes: solid, gelinite or fiber, and wherein said mass can be identical or different.

33. a method of making vibration isolator may further comprise the steps at least:

In the time will using vibration isolator to absorb vibration, determine pending frequency; (b) a plurality of mass are placed in the cover layer the uneven degree of depth and/or uneven mass and mass interval with this cover layer absorber be tuned to the determined frequency of step (a).

34. method as claimed in claim 33, wherein said cover layer is made by solid material.

35. method as claimed in claim 33, wherein said cover layer manufactures stratiform, and at least one mass is placed on specified location in the layer.

36. method as claimed in claim 35 comprises the layer thickness and/or the layer structure of variation.

37. method as claimed in claim 33, wherein said mass is inserted described cover layer with adhesive.

38. method as claimed in claim 33, wherein said mass is mechanically inserted described cover layer.

39. method as claimed in claim 33, wherein said mass have the weight in about 6 to 8 gram scopes individually.

40. method as claimed in claim 33, comprising the weight of the vibration isolator of the shaping of described mass in the per 16 square feet scope of about 300 to 400 grams.

41. method as claimed in claim 33 wherein comprises the mass of various sizes, various weight in cover layer.

42. a vibration isolator comprises:

The three-dimensional foam material;

A plurality of mass, these mass are distributed in the appointed positions place on the X-Y of described three-dimensional foam material size, and at the degree of depth place of appointment, the described appointed positions of described foamed material and the degree of depth of described appointment and physics or chemical attribute allow the vibration damping at the assigned frequency place along the z distribution of sizes of described three-dimensional foam material.

43. vibration isolator as claimed in claim 42, wherein said three-dimensional foam material is constructed by a plurality of froth beds.

44. vibration isolator as claimed in claim 42, each in wherein said a plurality of mass is inserted the opening in the described three-dimensional foam material.

45. vibration isolator as claimed in claim 44 also is included in the foam cap that is positioned in each opening on each mass.

46. vibration isolator as claimed in claim 42, at least some of wherein said a plurality of mass are metals.

47. vibration isolator as claimed in claim 42, at least some of wherein said a plurality of mass are gelinite, liquid or fiber.

48. one kind is used to vibrate or the dissimilar materials of sound dampening, comprises:

Foamed material;

Continuous or semi-continuous quality layers, this continuous or semi-continuous quality layers embeds in the described foamed material; With

One or more embedding mass, these mass are positioned at the position of variation and the degree of depth place that is changing along length or Width in described foamed material.

49. dissimilar materials as claimed in claim 48, wherein said foamed material is a sandwich construction.

50. a dissimilar materials, wherein said continuous or semi-continuous quality layers is along its length segmentation.

51. dissimilar materials as claimed in claim 50, wherein the segmentation position allows crooked.

52. dissimilar materials as claimed in claim 48, the mass of wherein said one or more embeddings is on described opposite side continuous or semi-continuous quality layers.

53. dissimilar materials as claimed in claim 48, the mass of wherein said one or more embeddings is on described same side continuous or semi-continuous quality layers.

54. dissimilar materials as claimed in claim 48, wherein said continuous or semi-continuous quality layers is a metal.

55. dissimilar materials as claimed in claim 41, the mass of wherein said embedding is of different sizes and shape.