EP0452370A1 - Systeme amortisseur en materiau visco-elastique - Google Patents

Systeme amortisseur en materiau visco-elastique

Info

Publication number
EP0452370A1
EP0452370A1 EP90901498A EP90901498A EP0452370A1 EP 0452370 A1 EP0452370 A1 EP 0452370A1 EP 90901498 A EP90901498 A EP 90901498A EP 90901498 A EP90901498 A EP 90901498A EP 0452370 A1 EP0452370 A1 EP 0452370A1
Authority
EP
European Patent Office
Prior art keywords
viscoelastic
bodies
vibrations
spacers
plates
Prior art date
Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
Withdrawn
Application number
EP90901498A
Other languages
German (de)
English (en)
Other versions
EP0452370A4 (en
Inventor
Leonard N. Thomasen
Current Assignee (The listed assignees may be inaccurate. Google has not performed a legal analysis and makes no representation or warranty as to the accuracy of the list.)
LIMBACH & LIMBACH
Original Assignee
Limbach & Limbach
Priority date (The priority date is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the date listed.)
Filing date
Publication date
Application filed by Limbach & Limbach filed Critical Limbach & Limbach
Publication of EP0452370A1 publication Critical patent/EP0452370A1/fr
Publication of EP0452370A4 publication Critical patent/EP0452370A4/en
Withdrawn legal-status Critical Current

Links

Classifications

    • H—ELECTRICITY
    • H04—ELECTRIC COMMUNICATION TECHNIQUE
    • H04R—LOUDSPEAKERS, MICROPHONES, GRAMOPHONE PICK-UPS OR LIKE ACOUSTIC ELECTROMECHANICAL TRANSDUCERS; DEAF-AID SETS; PUBLIC ADDRESS SYSTEMS
    • H04R1/00—Details of transducers, loudspeakers or microphones
    • H04R1/02—Casings; Cabinets ; Supports therefor; Mountings therein
    • H04R1/026—Supports for loudspeaker casings
    • F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
    • F16—ENGINEERING ELEMENTS AND UNITS; GENERAL MEASURES FOR PRODUCING AND MAINTAINING EFFECTIVE FUNCTIONING OF MACHINES OR INSTALLATIONS; THERMAL INSULATION IN GENERAL
    • F16F—SPRINGS; SHOCK-ABSORBERS; MEANS FOR DAMPING VIBRATION
    • F16F7/00—Vibration-dampers; Shock-absorbers
    • F16F7/10—Vibration-dampers; Shock-absorbers using inertia effect
    • F16F7/104—Vibration-dampers; Shock-absorbers using inertia effect the inertia member being resiliently mounted
    • F16F7/108—Vibration-dampers; Shock-absorbers using inertia effect the inertia member being resiliently mounted on plastics springs
    • G—PHYSICS
    • G10—MUSICAL INSTRUMENTS; ACOUSTICS
    • G10K—SOUND-PRODUCING DEVICES; METHODS OR DEVICES FOR PROTECTING AGAINST, OR FOR DAMPING, NOISE OR OTHER ACOUSTIC WAVES IN GENERAL; ACOUSTICS NOT OTHERWISE PROVIDED FOR
    • G10K11/00—Methods or devices for transmitting, conducting or directing sound in general; Methods or devices for protecting against, or for damping, noise or other acoustic waves in general
    • G10K11/16—Methods or devices for protecting against, or for damping, noise or other acoustic waves in general
    • G10K11/172—Methods or devices for protecting against, or for damping, noise or other acoustic waves in general using resonance effects

Definitions

  • This invention relates to a device and method for attenuating a selected wavelength band of vibrations produced by a vibrating member. More specifically, it is directed to a viscoelastic damping device which may be connected with a vibrating elastic member, such as a loudspeaker enclosure, so as to attenuate those vibrations. Additionally, the invention relates to a method of contacting an assembly including a viscoelastic material with a vibrating member, so as to attenuate a selected wavelength band of vibrations emanating therefrom.
  • the secondary vibrations of an enclosure are vibrations which may produce audible sound waves.
  • the acoustic output caused by these secondary vibrations may add or subtract from the output of the loudspeaker, thereby causing the listener to perceive the results as spectral changes or "coloration" of the sound being reproduced by the speaker.
  • the sound waves that are produced by a loudspeaker's enclosure panels are the result of energy that is injected into these panels by a low- frequency loudspeaker whose functional role is to reproduce the lower frequency range of the sound spectrum.
  • this low frequency energy is transferred into the enclosure panels, it is stored as periodic stress and recovered in the form of periodic deformations or, vibrations.
  • the resulting sound waves that these panel vibrations produce in the adjacent air will be dispersed along with the loudspeaker's main-signal energy.
  • the resulting two signals one being slightly delayed behind the other, will "smear" or interfere with the sound quality of the loudspeaker.
  • these delayed energy signals will alternately change in their phase relationship with the loudspeaker's main-signal sound waves. This disparity in phase relationships between the two signals over a wide range of frequencies will produce peaks and dips in the loudspeaker's frequency response causing the listener to perceive poorer quality reproduction.
  • braces which are secured against the inner walls of the enclosure to resist the periodic forces which cause the enclosure panels to vibrate.
  • the braces are made of materials which classify them as an elastic solid. Having elastic material properties makes these braces suitable for transmitting energy but not for attenuating or absorbing energy.
  • elastic solid it is meant a material composed of individual atoms or small molecules in crystalline lattices. In these materials, molecular motion is rapid and short-range.
  • spikes are intended to penetrate carpets and ultimately embed themselves into the floor. This was done to route the mechanical energy originating in the loudspeaker's enclosure by transmitting it directly into the floor. The attempt in this design was to inject some of the energy which causes panel vibrations in the enclosure into the floor where it might be dissipated in the floor material.
  • the absorption of mechanical energy in a floor using spikes as a medium of energy transmission and ultimate absorption is indeterminate and unpredictable in its results.
  • a floor may be made of concrete, hardwood, vitreous clay tile, linoleum or, for that matter, any number of materials, the physical properties of which vary as widely as does their ability to absorb energy in a useful way.
  • the use of steel spikes fails to provide the means necessary to reduce the velocity and, hence, the amplitude of the enclosure vibrations to a degree that will render the perceived acoustical affect of such vibrations less disturbing to the listener.
  • isolation pads are commonly made of materials such as silicone or rubber. These materials are composed essentially of extremely high-molecular-weight molecules having long chains of repeating smaller molecules. These chemical bonds give such materials as silicone and rubber their low molecular flexibility. As a result, whenever forces are exerted into such materials, including high velocity periodic forces such as those exhibited by a loudspeaker enclosure panel, these materials act as barriers which prevent such energy from further propagation, thereby isolating the vibrational energy in the loudspeaker enclosure. For this reason the energy will not transfer out of the enclosure but will continue to produce periodic panel vibrations along with the corresponding objectionable delayed- energy sound waves.
  • U.S. Patent No. 4,778,028 teaches the use of honeycomb-type structural layers mounted on opposite sides of a viscoelastic damping layer such that all of the layers have the same cross-sectional area. This design is said to provide structural stability to the surface to which the layer is attached, such as a satellite which will be subjected to various forces.
  • Japanese Patent No. 62-209996 discloses one type of damping device that can be attached to a speaker box.
  • the damping device of this patent does not address the use of viscoelastic materials in such an application.
  • the present invention provides a device for attenuating a selected wavelength band of vibrations produced by a vibrating member comprising a viscoelastic body particularly shaped to attenuate vibrations within the selected wavelength band, and means for transmitting that selected wavelength band of vibrations from the vibrating member to the viscoelastic body.
  • attenuation of a selected wavelength band it is meant that the invention is designed to attenuate vibrations continuously over such a wavelength band, or at discrete, smaller, frequencies within an overall band.
  • the device of the present invention may include a transmitting or mounting means which is also used to mount the viscoelastic vibration absorbing body on the vibrating member.
  • the vibration absorbing body of the invention may be made from any suitable polymeric viscoelastic material.
  • Acrylonitrile- butadiene-styrene terpolymer and other butadiene- styrene copolymers are preferred.
  • the present invention is directed to a vibration absorbing assembly comprising a plurality of viscoelastic plates which are severed across their width and spaced apart, the outer edges of each plate being fastened to a spacer.
  • This assembly may be advantageously mounted to the inside of a loudspeaker enclosure panel to attenuate vibrations in the audible frequency range from 20 to 20,000 hertz, and is constructed to be especially absorbing in the range approximating 40 to 1000 hertz.
  • the present invention is directed to a vibration absorbing assembly comprising a plurality of viscoelastic plates, each plate separated from adjacent plates by a separator located near the center of the plate and having a smaller cro ⁇ s-sectional area than the plate.
  • This assembly may be advantageously mounted on a loudspeaker enclosure panel to attenuate vibrations in the audible frequency range from 20 to 20,000 hertz, and is constructed to be especially absorbing in the range approximating 40 to 1000 hertz.
  • the sound absorbing assembly may be mounted on a loudspeaker stand, where the stand is made from an elastic material which will transmit vibrations from a speaker enclosure to the assembly.
  • the invention further comprises a method of attenuating vibrations in a selected wavelength band emanating from a vibrating source comprising the step of contacting a viscoelastic body with a vibrating elastic source, where the viscoelastic body is particularly shaped to attenuate vibrations in a selected wavelength band.
  • the method further comprises mounting said viscoelastic body adjacent a loudspeaker enclosure panel, or alternatively, on a loudspeaker stand.
  • FIGURE 1 is a side view of the first embodiment of the vibration absorbing assembly of the present invention
  • FIGURE 2 is a perspective view of the sound absorbing assembly of FIGURE 1;
  • FIGURE 3 is a side view of the second embodiment of the vibration absorbing assembly of the present invention
  • FIGURE 4 is a perspective view of the sound absorbing assembly of FIGURE 3 ;
  • FIGURE 5 is a view of the vibration absorbing assembly of FIGURE 1 mounted on a loudspeaker stand;
  • FIGURE 6 is a side, partial cut away, view of a loudspeaker upon which the vibration absorbing assembly of FIGURE 1 is mounted;
  • FIGURE 7 is a line graph comparing the amplitude of enclosure panel vibrations without the damping system of FIGURE 3 secured to the panel, and with the damping system of FIGURE 3 secured to the panel.
  • FIG. 1 a side view of the structure of the first embodiment is shown, in this structure, plates 1 of assembly A are separated by spacers 2. Plates 1 and spacers 2 are securely fixed together so as to form a monolithic structure.
  • the spacers 2 serve two important functions according to the invention: first, they prevent the plates 1 from coming into contact with each other. Second, the cross-sectional area of the spacers relative to the plates can be made to govern the resonance frequency of plates 1 adjoining the spacers.
  • mounting block 3 and bolt 4 may be used to affix the combination of plates 1 and spacers 2 which make up the vibration attenuating assembly A of the invention to an appropriate vibrating surface, such as a loudspeaker enclosure. It is noted, however, that assembly A may be mounted on vibrating surfaces other than speaker enclosures and still provide beneficial attenuating characteristics.
  • the dimensions of plates 1, the dimensions of the spacers 2, the dimensions of the plates 1 versus spacers 2, the type of viscoelastic material used for the plates 1, the type of viscoelastic or elastic material used for the spacers 2, and the distance between the plates and the vibrating member will define the wavelength band or bands to which assembly A is tuned.
  • the assembly can be sized to absorb vibrations over a wide range of wavelengths.
  • FIG. 2 A perspective view of the plates 1 of the first embodiment is shown in FIG. 2. Of course, spacers can not be seen in this view.
  • the vibration damping device contains three absorption plates 1 with two intermediate spacers 2 between the plates.
  • the thickness of the absorption plates 1 is 1/8 of an inch and the thickness of the intermediate spacers 2 measures 1/4 inch.
  • the plates are of the same size and measure about 8 inches in height by 6 inches in width. It is to be noted, however, that these thicknesses and shapes may be substantially varied yet still obtain good attenuation characteristics. Varying thicknesses and cross-sectional areas of plates versus spacers, relative to one another simply adjusts the natural resonances of the assembly to different wavelength bands, and the particular wavelength band for a given construction is easily determined by applying vibrational stress to the assembly and measuring the resulting degree of absorption.
  • hole 5 (FIG. 2) with a diameter of approximately 3/8 inch, located at the center of the damping plates, passes directly through the vibration damping device, thereby providing a means for attaching the damping device directly onto a vibrating member.
  • Mounting block 3 preferably made of the same material as the enclosure panel (usually particle board) , has a threaded connector at its center (not shown) .
  • bolt 4 passes through to thread into the threaded connector of the mounting block.
  • the block is preferably glued to the enclosure panel before the speaker enclosure is assembled.
  • Mounting block 3 serves three important functions.
  • FIG. 3 a side view of the structure of the second embodiment is shown.
  • one-piece plates 1A and two-piece plates 1 of assembly C are separated by spacers 2.
  • a two- piece plate 1 differs from a one-piece plate 1A in that the two-piece plate 1 is completely severed across its width so as to form two pieces of the plate. The two pieces are then spaced apart from each other so as not to be in vibrational contact with each other.
  • the longitudinal location at which the plate is to be severed across its width will be chosen according to the wavelengths to be attenuated, and can vary from one two-piece plate to another.
  • One-piece plates 1A, two-piece plates 1 and spacers 2 are securely fixed together so as to create a monolithic structure.
  • the mounting blocks 3 and bolts 4 may be used to affix the combination of plates 1 and spacers 2 which make up the vibration attenuating assembly C of the invention to an appropriate vibrating surface, such as a loudspeaker enclosure.
  • assembly C may be mounted on vibrating surfaces other than speaker enclosures and still provide beneficial attenuating characteristics.
  • the dimensions of the one-piece plates 1A, the dimensions of the two-piece plates 1, the dimensions of the spacers 2, the dimensions of the one-piece plates 1A and the two-piece plates 1 versus spacers 2, the viscoelastic material of the one-piece plates 1A and the two-piece plates 1, the elastic or viscoelastic material of the spacers 2, and the distance between the plates and the vibrating member will define the wavelength band or bands to which assembly C is tuned.
  • the assembly can be sized to absorb vibrations over a wide range of wavelengths.
  • FIG. 4 A perspective view of the one-piece plates 1A and the two-piece plates 1 of the second embodiment is shown in FIG. 4. Spacers 2 can be seen in this view.
  • the vibration damping device contains two one-piece absorption plates 1A, three two-piece absorption plates 1, and four pair of two intermediate spacers 2 between the plates such that one spacer separates each plate at either end of the plates.
  • the thickness of the one-piece plates 1A and two-piece plates 1 is 1/8 of an inch and the thickness of the intermediate spacers 2 measures 1/4 inch.
  • the plates are of the same size and measure about 8 inches in height by 6 inches in width.
  • the lowest two-piece plate is severed across Its width at a longitudinal point 3.5 inches from its left longitudinal end
  • the middle two-piece plate is severed across its width at a longitudinal point 4 inches from its left longitudinal end
  • the highest two-piece plate is severed across its width at a longitudinal point 4.5 inches from its left longitudinal end, as shown in FIG. 3.
  • the frequency range attenuated most substantially by the lower one- piece plate in FIG. 3 is approximately 190-350 hertz.
  • FIG. 3 is approximately 750-1000 hertz, and is nearly identical to the range substantially attenuated by the right segment of the highest two-piece segment.
  • the frequency range attenuated most substantially by the right segment of the lowest two-piece plate in FIG.3 is approximately 300-625 hertz, and is nearly identical to the range substantially attenuated by the left segment of the highest two-piece segment.
  • FIG. 3 is approximately 390-750 hertz, and is nearly identical to the range substantially attenuated by the right segment of the middle two-piece plate.
  • the frequency range attenuated most substantially by the upper one-piece plate in FIG. 3 is approximately 750- 1000 hertz. It is to be noted, however, that these thicknesses, points of severance and shapes may be substantially varied to obtain attenuation characteristics at selected wavelengths. Varying thicknesses and cross-sectional areas of plates versus spacers, relative to one another simply adjusts the natural resonances of the assembly to different wavelength bands, and the particular wavelength band for a given construction is easily determined by applying vibrational stress to the assembly and measuring the resulting degree of absorption. This is most easily achieved by trial and error with the aid of standard accelerometer measuring techniques.
  • the holes 5 with a diameter of approximately 3/8 inch, located at either end of the damping plates so as to be centered along the width of the plates, passes directly through the vibration damping device, thereby providing a means for attaching the damping device directly onto a vibrating member.
  • the mounting blocks 3, preferably made of the same material as the enclosure panel (usually particle board) have a threaded connector at there center (not shown) . Through each of the holes 5 in the vibration damping device, a bolt 4 passes through to thread into the threaded connector of each mounting block.
  • the blocks are preferably glued to the enclosure panel before the speaker enclosure is assembled.
  • the mounting blocks 3 serve three important functions according to the invention: first; they separate the vibration damping system away from the enclosure panel to prevent the absorption plate nearest the enclosure panel from striking the enclosure. Second, their size can be made to govern the resonance frequency of the absorption plate located nearest to the enclosure panel. Third, they form the means necessary to secure the damping device onto the vibrating surface.
  • the embodiment of FIGS. 3 and 4 is especially advantageous in practice because of the flexibility allowed by using the two piece plates to tune the assembly to attenuate at whatever wavelengths are desired, but still maintaining a small size so that the entire assembly will easily fit inside a speaker cabinet.
  • the number of plates and spacers can be varied.
  • a single viscoelastic plate spaced by a single spacer or mounting block from a vibrating surface will absorb energy therefrom.
  • the assembly may comprise a single plate and spacer, or two plates and two spacers. More plates provide greater ability to absorb energy, however, and a three plate assembly has been shown to be effective with loudspeakers for vibrations in the audible range. Other applications may require more, or larger or smaller, plates and spacers.
  • the absorption plates 1 may be made of any suitable viscoelastic material.
  • viscoelastic it is meant materials which have both elastic properties like a solid, and viscous properties like a liquid.
  • the strain on the body is neither exactly in phase with the oscillating stress, as it would be with a perfectly elastic solid, nor 90 degrees out of phase, as it would be with a perfectly viscous liquid. Rather, it is somewhere between these conditions.
  • some of the vibrational energy input to the viscoelastic material of the plates is stored and recovered in each cycle of the vibrations, while some of the energy is dissipated as heat.
  • Viscoelastic polymeric materials that can be used to form the absorption plates and intermediate spacers include ABS (terpolymer of acrylonitrile, butadiene and styrene) , polyamides such as nylon 66, polycarbonates, polyethylene, polypropylene, polystyrene, styrene-butadiene copolymers, polyfluorocarbons such as polytetrafluoroethylene and rubber-modified polystyrene.
  • ABS terpolymer of acrylonitrile, butadiene and styrene
  • polyamides such as nylon 66
  • polycarbonates polyethylene, polypropylene, polystyrene, styrene-butadiene copolymers
  • polyfluorocarbons such as polytetrafluoroethylene and rubber-modified polystyrene.
  • a preferred material is high-impact polystyrene. These polymers have 8-10% butadiene or butadiene- styrene copolymers dispersed in a polystyrene matrix. An intermediate graft copolymer may be introduced to increase the compatibility between the polystyrene and butadiene phases. High-impact styrene is particularly advantageous material for the absorption plates. As the periodic or sinusoidally oscillating forces originating in the vibrations transfer into the polystyrene matrix, these forces propagate directly through the polystyrene, which being the more rigid phase of the polystyrene matrix, facilitates energy propagation.
  • An example of a high-impact polystyrene suitable for absorption plates and intermediate spacers according to the invention is STYRON R 479 impact polystyrene resins.
  • This high-impact polystyrene contains 8-10% butadiene and has a specific gravity of 1.05 g/cm 3 and a flexural strength of 4,700 lbs/in 2 .
  • the plate and spacer design of the vibration damping assembly of this invention is an important feature of the invention.
  • the absorption plates and intermediate spacers should be bonded together to form a monolithic structure.
  • monolithic it is mean that all elements of the absorbing structure are -17- firmly in contact with one another, with no loose plates or spacers.
  • an important feature of the invention is the cross-sectional area of the absorption plates relative to the cross-section of the intermediate spacers. These areas can be varied to produce a desired resonance frequency or combination of resonance frequencies for the vibration damping device.
  • the intermediate spacers and absorption plates are bonded together to form a monolithic structure and therefore, the absorption plates, being much larger in size than the intermediate spacers form a mass-spring system which will resonate sympathetically to a prescribed excitation frequency governed by the equation;
  • damping assembly A of the first configuration of the invention is shown mounted on speaker stand 7 which supports loudspeaker enclosure 8. It should be noted that, while damping assembly A effectively attenuates speaker vibrations when attached to a speaker stand as shown in FIG. 5, damping assembly A is shown for illustrative purposes only, and that damping assembly C of the second configuration of the invention can be mounted on the speaker stand in place of damping assembly A to effectively attenuate speaker vibration.
  • the geometry of stand 7 may be any configuration which is aesthetically desirable as long as the material from which it is made is sufficiently elastic to efficiently transmit vibrations received from enclosure 8 to damping assembly A.
  • the type of structure shown in FIG. 5 is desirable in that such a stand may be purchased by a consumer who already owns loudspeakers.
  • the damping assembly may be mounted by any means which provides direct contact between the mounting block 9 and the base of speaker stand 7.
  • the damping assembly may be bolted or glued to the stand.
  • the damping assembly may be sufficiently affixed to the stand (or speaker enclosure panel as further described below with regard to FIG. 6) by adhering a magnet to the speaker stand, or speaker enclosure itself, and a mating metal piece on the opposing surface of the damping assembly.
  • the size of the magnet necessary will, of course, depend on the size and weight of the damping assembly used in a particular instance.
  • the material from which the spacers of the invention are made may be any suitable viscoelastic or elastic material, but may not be an insulating material such as soft rubber.
  • metal spacers may be used since these will readily transmit vibrations to the assembled vibration absorbing plates.
  • loudspeaker 10 is shown housed within loudspeaker enclosure 11.
  • the damping assembly A of the first configuration is shown mounted on the rear panel of enclosure 8. While damping assembly A is shown mounted on the exterior of enclosure 8, it has been found that equally effective damping is obtained if the assembly is mounted wholly within enclosure 8.
  • damping assembly A has been chosen for illustrative purposes only, and that damping assembly C of the second configuration can be mounted in place of damping assembly A on the exterior or interior of the enclosure 8 to effectively attenuate loudspeaker vibrations.
  • damping assembly is included as an original piece by the loudspeaker manufacturer, it may be aesthetically desirable to contain the assembly within the enclosure.
  • damping assembly On the side walls and the rear wall of the enclosure since these panels exhibit the greatest periodic deformations during operation of the loudspeaker. Adequate damping may, however, be achieved by placing the damping assembly in any portion of the loudspeaker enclosure where a modal analysis of the enclosure indicates portions which would benefit most.
  • the invention further includes a novel method of attenuating vibrations in a selected wavelength band emanating from a vibrating source by contacting a viscoelastic absorbing body to the source.
  • the viscoelastic body may be mounted to and contacted directly with the vibrating source.
  • the body may be mounted on any material which will transmit vibrations from the vibrating source to the viscoelastic assembly, such as a stand formed from an elastic material, upon which the vibrating source rests.

Landscapes

  • Engineering & Computer Science (AREA)
  • Physics & Mathematics (AREA)
  • Acoustics & Sound (AREA)
  • General Engineering & Computer Science (AREA)
  • Signal Processing (AREA)
  • Multimedia (AREA)
  • Mechanical Engineering (AREA)
  • Vibration Prevention Devices (AREA)

Abstract

Dans l'ensemble amortisseur de vibrations décrit est incorporé un corps atténuateur (A) formé à partir d'un matériau visco-élastique. Dans un mode de réalisation préféré, le corps (A) peut être constitué de plusieurs plaques (1) empilées les unes sur les autres et séparées par des pièces d'espacement (2). Un matériau visco-élastique est de préférence constitué par du polystyrène à haute résistance aux chocs. Un tel système amortisseur est de préférence monté sur un panneau, d'enceinte d'un haut-parleur (8) pour atténuer les vibrations du panneau, réduisant ainsi au minimum les signaux audio qui en émanent généralement et qui interfèrent avec la sortie de haut-parleur désirée.
EP19900901498 1988-12-30 1989-12-29 Viscoelastic damping system Withdrawn EP0452370A4 (en)

Applications Claiming Priority (2)

Application Number Priority Date Filing Date Title
US29241288A 1988-12-30 1988-12-30
US292412 1988-12-30

Publications (2)

Publication Number Publication Date
EP0452370A1 true EP0452370A1 (fr) 1991-10-23
EP0452370A4 EP0452370A4 (en) 1991-12-18

Family

ID=23124556

Family Applications (1)

Application Number Title Priority Date Filing Date
EP19900901498 Withdrawn EP0452370A4 (en) 1988-12-30 1989-12-29 Viscoelastic damping system

Country Status (3)

Country Link
EP (1) EP0452370A4 (fr)
JP (1) JPH04504621A (fr)
WO (1) WO1990007673A1 (fr)

Cited By (1)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
EP0658872A2 (fr) * 1993-12-16 1995-06-21 Daimler-Benz Aerospace Aktiengesellschaft Dispositif d'absorption à résonance

Families Citing this family (7)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
FR2777409A1 (fr) * 1998-04-10 1999-10-15 Alain Pratali Procede de fabrication d'enceinte acoustique pour hauts parleurs electrodynamiques
GB2339002A (en) * 1998-07-01 2000-01-12 Neville Spencer Francis Vibration suppressing support table
GB2350965B (en) * 1999-06-10 2001-08-22 Stefan Gamble Loudspeaker cabinet and microphone housing internal damping system
FR2850484B1 (fr) * 2003-01-24 2005-12-09 Hutchinson Structure mecanique presentant une propriete vibratoire modifiable
ES2314762T3 (es) * 2005-02-22 2009-03-16 Franz Mitsch Amortiguador ajustable de tras ejes.
JP5330887B2 (ja) * 2009-04-07 2013-10-30 積水化学工業株式会社 床構造、建物ユニット及びユニット建物
WO2013023724A1 (fr) 2011-08-18 2013-02-21 Fm Energie Gmbh & Co. Kg Absorbeur de vibrations indépendant de la température

Citations (1)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
GB2021501A (en) * 1978-04-17 1979-12-05 Krupp Ag Huettenwerke Rail wheel and rail system equipped with resonance absorbers

Family Cites Families (9)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US2270902A (en) * 1939-11-25 1942-01-27 George A Rubissow Antivibration means and method of use of same
US2541159A (en) * 1946-01-22 1951-02-13 Paul H Geiger Sound deadener for vibratory bodies
US3160549A (en) * 1960-12-29 1964-12-08 Minnesota Mining & Mfg Vibration damping structures
US3102722A (en) * 1961-12-11 1963-09-03 Hugh C Hamontre Self damping shock and vibration mount
US3386527A (en) * 1965-08-05 1968-06-04 Daubert Chemical Co Adhesive sound damping tape for application to vibrating panels
US3388772A (en) * 1966-06-16 1968-06-18 Continental Motors Corp Vibration absorber
JPS6152153A (ja) * 1984-08-20 1986-03-14 Hitachi Metals Ltd スイツチングレギユレ−タ
US4734323A (en) * 1986-04-22 1988-03-29 Toyoda Gosei Co., Ltd. Vibration damping soundproof sheets for use in vehicles
US4778028A (en) * 1986-11-03 1988-10-18 General Electric Company Light viscoelastic damping structure

Patent Citations (1)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
GB2021501A (en) * 1978-04-17 1979-12-05 Krupp Ag Huettenwerke Rail wheel and rail system equipped with resonance absorbers

Non-Patent Citations (1)

* Cited by examiner, † Cited by third party
Title
See also references of WO9007673A1 *

Cited By (2)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
EP0658872A2 (fr) * 1993-12-16 1995-06-21 Daimler-Benz Aerospace Aktiengesellschaft Dispositif d'absorption à résonance
EP0658872A3 (fr) * 1993-12-16 1996-02-07 Daimler Benz Aerospace Ag Dispositif d'absorption à résonance.

Also Published As

Publication number Publication date
JPH04504621A (ja) 1992-08-13
EP0452370A4 (en) 1991-12-18
WO1990007673A1 (fr) 1990-07-12

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