EP0013513A1 - Sound absorbing structure - Google Patents

Sound absorbing structure Download PDF

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Publication number
EP0013513A1
EP0013513A1 EP79303073A EP79303073A EP0013513A1 EP 0013513 A1 EP0013513 A1 EP 0013513A1 EP 79303073 A EP79303073 A EP 79303073A EP 79303073 A EP79303073 A EP 79303073A EP 0013513 A1 EP0013513 A1 EP 0013513A1
Authority
EP
European Patent Office
Prior art keywords
foil
sheet material
sound absorbing
netting
absorbing structure
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.)
Granted
Application number
EP79303073A
Other languages
German (de)
French (fr)
Other versions
EP0013513B1 (en
Inventor
Kurt Hjelholt
Niels Christian Dyrving
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.)
Daempa AS
Original Assignee
Daempa AS
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 Daempa AS filed Critical Daempa AS
Priority to AT79303073T priority Critical patent/ATE9017T1/en
Publication of EP0013513A1 publication Critical patent/EP0013513A1/en
Application granted granted Critical
Publication of EP0013513B1 publication Critical patent/EP0013513B1/en
Expired legal-status Critical Current

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Classifications

    • E—FIXED CONSTRUCTIONS
    • E04—BUILDING
    • E04B—GENERAL BUILDING CONSTRUCTIONS; WALLS, e.g. PARTITIONS; ROOFS; FLOORS; CEILINGS; INSULATION OR OTHER PROTECTION OF BUILDINGS
    • E04B9/00—Ceilings; Construction of ceilings, e.g. false ceilings; Ceiling construction with regard to insulation
    • E04B9/04—Ceilings; Construction of ceilings, e.g. false ceilings; Ceiling construction with regard to insulation comprising slabs, panels, sheets or the like
    • E04B9/045—Ceilings; Construction of ceilings, e.g. false ceilings; Ceiling construction with regard to insulation comprising slabs, panels, sheets or the like being laminated
    • E—FIXED CONSTRUCTIONS
    • E04—BUILDING
    • E04B—GENERAL BUILDING CONSTRUCTIONS; WALLS, e.g. PARTITIONS; ROOFS; FLOORS; CEILINGS; INSULATION OR OTHER PROTECTION OF BUILDINGS
    • E04B1/00—Constructions in general; Structures which are not restricted either to walls, e.g. partitions, or floors or ceilings or roofs
    • E04B1/62—Insulation or other protection; Elements or use of specified material therefor
    • E04B1/74—Heat, sound or noise insulation, absorption, or reflection; Other building methods affording favourable thermal or acoustical conditions, e.g. accumulating of heat within walls
    • E04B1/82—Heat, sound or noise insulation, absorption, or reflection; Other building methods affording favourable thermal or acoustical conditions, e.g. accumulating of heat within walls specifically with respect to sound only
    • E04B1/84—Sound-absorbing elements
    • E04B1/8409—Sound-absorbing elements sheet-shaped
    • E—FIXED CONSTRUCTIONS
    • E04—BUILDING
    • E04B—GENERAL BUILDING CONSTRUCTIONS; WALLS, e.g. PARTITIONS; ROOFS; FLOORS; CEILINGS; INSULATION OR OTHER PROTECTION OF BUILDINGS
    • E04B1/00—Constructions in general; Structures which are not restricted either to walls, e.g. partitions, or floors or ceilings or roofs
    • E04B1/62—Insulation or other protection; Elements or use of specified material therefor
    • E04B1/74—Heat, sound or noise insulation, absorption, or reflection; Other building methods affording favourable thermal or acoustical conditions, e.g. accumulating of heat within walls
    • E04B1/82—Heat, sound or noise insulation, absorption, or reflection; Other building methods affording favourable thermal or acoustical conditions, e.g. accumulating of heat within walls specifically with respect to sound only
    • E04B1/84—Sound-absorbing elements
    • E04B2001/8457—Solid slabs or blocks
    • E04B2001/8461—Solid slabs or blocks layered
    • E—FIXED CONSTRUCTIONS
    • E04—BUILDING
    • E04B—GENERAL BUILDING CONSTRUCTIONS; WALLS, e.g. PARTITIONS; ROOFS; FLOORS; CEILINGS; INSULATION OR OTHER PROTECTION OF BUILDINGS
    • E04B1/00—Constructions in general; Structures which are not restricted either to walls, e.g. partitions, or floors or ceilings or roofs
    • E04B1/62—Insulation or other protection; Elements or use of specified material therefor
    • E04B1/74—Heat, sound or noise insulation, absorption, or reflection; Other building methods affording favourable thermal or acoustical conditions, e.g. accumulating of heat within walls
    • E04B1/82—Heat, sound or noise insulation, absorption, or reflection; Other building methods affording favourable thermal or acoustical conditions, e.g. accumulating of heat within walls specifically with respect to sound only
    • E04B1/84—Sound-absorbing elements
    • E04B2001/8457—Solid slabs or blocks
    • E04B2001/8476—Solid slabs or blocks with acoustical cavities, with or without acoustical filling

Definitions

  • the specification of Danish Patent No. 128 947 discloses a sound absorbing ceiling lining consisting of elements of thin perforated sheet material and an absorption material, such as mineral wool batts, disposed in these elements, and an air and particle intercepting foil inserted between the sheet material and the absorption material, said foil being adhered to the sheet material in a cross pattern consisting of two intersecting sets of continuous glue stripes.
  • the foil is preferably a plastic foil having a thickness of about 10v or less, and that it forms a kind of checkered coating on the upper side of the sheet material, the glue stripes dividing the foil into a large number of generally rectangular, possibly square, sections having normally a side length of the order of one or a few centimetres.
  • the stated purpose is to prevent an air flow along the upper side of the sheet material and thereby also to counteract an air circulation through this perforated sheet material, without substantially reducing the sound absorbing effect, especially in the high frequency range, as would be the case when a tight foil were glued flat to the perforated sheet material.
  • the known ceiling lining when applied in practice, has proved not to come up, in all cases, to expectations with regard to the sound absorbing effect.
  • the plastic foil has turned out to have a reducing effect on the sound absorbing capacity of the mineral wool, to such extent, in some cases, that the mineral wool becomes almost ineffective, irrespective of its thickness.
  • this reducing effect varies substantially dependent on the physical characteristics of the plastic foil, especially its composition, its melting point, and its thickness and variations in thickness, and it has been found that these factors can vary in one and the same roll of plastic foil to such an extent as to strongly influence the said reducing effect.
  • the glue stripes constitute a further important factor, as it can be difficult to control their thickness and width with sufficient accuracy, and because they must be expected, by providing a direct contact between the foil and the sheet material, to reduce the effective absorption area proportionally to the area of the glue stripes.
  • the present invention has for its object to provide a sound absorbing structure consisting also of perforated sheet and foil but having a sound absorbing capacity which even under practical conditions can be controlled adequately.
  • the invention relates to a sound absorbing structure consisting, in a conventional manner, of thin, perforated sheet material, such as aluminium sheet, and a foil secured to one side of said sheet, preferably a plastic foil having af thickness of about 10-50p.
  • the structure according to the invention differs from the known designs of same type in that between its securing points, the foil is spaced a distance from the sheet material which is optimum as far as sound absorption is concerned. This can in practice be conveniently achieved by the insertion, between the sheet material and the foil, of a netting which by glueing or welding is attached to the sheet material as well as to the foil and which has a mesh size of the order of 1-5 mm.
  • the sound absorbing effect is due to the fact that the foil is divided into a great number of small areas or small diaphragms, which vibrate or oscillate independently and out of time with the vibrations of the perforated sheet material.
  • a further probable explanation may be that the provision is made between the foil and the sheet material of a layer of air-filled cells to which an access is provided through the perforations of the sheet material. These individual cells have a sound quenching effect.
  • the cavity absorption generally obtained by mineral wool is also obtained by the structure according to the invention, so that additional measures to that effect are reduced to a minimum.
  • the said diaphragms or cells are given a regular shape, for example a quadratic or hexagonal shape, but this is of minor importance, since a gauze-like material, such as glass fiber gauze, has also proved suitable instead of a netting provided with regular meshes.
  • An important advantage of the sound absorbing structure according to the invention is that unintended variations in the applied foil, especially variations in thickness and composition, have practically no importance for the sound absorbing capacity of the finished structure.
  • the desired distance between the sheet material and the foil can also be secured in another way than by sandwiching of netting or the like between the parts in question, as the netting may form part of the foil, or said foil and/or the sheet material may be provided with low ribs or protuberances to secure the required spacing.
  • the structure comprises a rectangular sheet 1 of steel or aluminium which is perforated between the parallel lines 2,2 so that a pair of opposite marginal portions 3,3 are left without perforations.
  • the netting 5 is adhesively attached to both the plastic foil 4 and the metal sheet 1 and forms a layer of air-filled cells therebetween which are closed by the plastic foil or film but communicate with the surrounding air through the perforations of the metal sheet 1.

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  • Physics & Mathematics (AREA)
  • Engineering & Computer Science (AREA)
  • Architecture (AREA)
  • Acoustics & Sound (AREA)
  • Electromagnetism (AREA)
  • Civil Engineering (AREA)
  • Structural Engineering (AREA)
  • Building Environments (AREA)
  • Vehicle Interior And Exterior Ornaments, Soundproofing, And Insulation (AREA)
  • Soundproofing, Sound Blocking, And Sound Damping (AREA)
  • External Artificial Organs (AREA)
  • Golf Clubs (AREA)
  • Waveguide Aerials (AREA)
  • Pharmaceuticals Containing Other Organic And Inorganic Compounds (AREA)
  • Nitrogen And Oxygen Or Sulfur-Condensed Heterocyclic Ring Systems (AREA)
  • Nitrogen Condensed Heterocyclic Rings (AREA)

Abstract

A sound absorbing structure, for instance in the form of a ceiling lining element, consisting of perforated sheet material (3) covered on one side by the foil (4), suitably of plastics, which by means of a netting (5) or in another manner, is spaced a short distance from the sheet material.

Description

  • The specification of Danish Patent No. 128 947 discloses a sound absorbing ceiling lining consisting of elements of thin perforated sheet material and an absorption material, such as mineral wool batts, disposed in these elements, and an air and particle intercepting foil inserted between the sheet material and the absorption material, said foil being adhered to the sheet material in a cross pattern consisting of two intersecting sets of continuous glue stripes. The specification states that the foil is preferably a plastic foil having a thickness of about 10v or less, and that it forms a kind of checkered coating on the upper side of the sheet material, the glue stripes dividing the foil into a large number of generally rectangular, possibly square, sections having normally a side length of the order of one or a few centimetres. The stated purpose is to prevent an air flow along the upper side of the sheet material and thereby also to counteract an air circulation through this perforated sheet material, without substantially reducing the sound absorbing effect, especially in the high frequency range, as would be the case when a tight foil were glued flat to the perforated sheet material.
  • The known ceiling lining, when applied in practice, has proved not to come up, in all cases, to expectations with regard to the sound absorbing effect. Thus, the plastic foil has turned out to have a reducing effect on the sound absorbing capacity of the mineral wool, to such extent, in some cases, that the mineral wool becomes almost ineffective, irrespective of its thickness. Furthermore, this reducing effect varies substantially dependent on the physical characteristics of the plastic foil, especially its composition, its melting point, and its thickness and variations in thickness, and it has been found that these factors can vary in one and the same roll of plastic foil to such an extent as to strongly influence the said reducing effect. The glue stripes constitute a further important factor, as it can be difficult to control their thickness and width with sufficient accuracy, and because they must be expected, by providing a direct contact between the foil and the sheet material, to reduce the effective absorption area proportionally to the area of the glue stripes.
  • Starting from the above known technique, the present invention has for its object to provide a sound absorbing structure consisting also of perforated sheet and foil but having a sound absorbing capacity which even under practical conditions can be controlled adequately.
  • More specifically, the invention relates to a sound absorbing structure consisting, in a conventional manner, of thin, perforated sheet material, such as aluminium sheet, and a foil secured to one side of said sheet, preferably a plastic foil having af thickness of about 10-50p. The structure according to the invention differs from the known designs of same type in that between its securing points, the foil is spaced a distance from the sheet material which is optimum as far as sound absorption is concerned. This can in practice be conveniently achieved by the insertion, between the sheet material and the foil, of a netting which by glueing or welding is attached to the sheet material as well as to the foil and which has a mesh size of the order of 1-5 mm.
  • In spite of comprehensive experiments and theoretical analyses, it has not been possible to find an unambiguous explanation of the reason why the distance between the foil and the sheet material is of decisive importance to the sound absorbing capacity, but it has been found that in the structure according to the invention, there is such an interaction between the perforated sheet material, the air-filled cavity, and the foil that a satisfactory sound absorption can be achieved without using any mineral wool or other porous material. This is, needles to say, , of great interest not only from an economic point of view but also for the quality of environment, as such materials are liable to cause dust nuisances.
  • It can be regarded as established that the sound absorbing effect, at any rate to a great extent, is due to the fact that the foil is divided into a great number of small areas or small diaphragms, which vibrate or oscillate independently and out of time with the vibrations of the perforated sheet material. A further probable explanation may be that the provision is made between the foil and the sheet material of a layer of air-filled cells to which an access is provided through the perforations of the sheet material. These individual cells have a sound quenching effect. It has also been established that the cavity absorption generally obtained by mineral wool is also obtained by the structure according to the invention, so that additional measures to that effect are reduced to a minimum. When using a netting as stated above, the said diaphragms or cells are given a regular shape, for example a quadratic or hexagonal shape, but this is of minor importance, since a gauze-like material, such as glass fiber gauze, has also proved suitable instead of a netting provided with regular meshes.
  • An important advantage of the sound absorbing structure according to the invention is that unintended variations in the applied foil, especially variations in thickness and composition, have practically no importance for the sound absorbing capacity of the finished structure. Said capacity may, on the other hand, be varied within a rather wide=range, if so desired, in particular according to the prevailing frequency range, by changing the thickness and perforation ratio of the sheet material, the thickness of the foil and the netting, and the size and shape of the net meshes. This enables an economical manufacture of structures having specific sound absorbing characteristics, in order, for instance, to meet requirements as to tailored sound absorption.
  • The desired distance between the sheet material and the foil can also be secured in another way than by sandwiching of netting or the like between the parts in question, as the netting may form part of the foil, or said foil and/or the sheet material may be provided with low ribs or protuberances to secure the required spacing.
  • A preferred embodiment of the sound absorbing structure is illustrated on the accompanying drawing.
  • In the embodiment of the drawing the structure comprises a rectangular sheet 1 of steel or aluminium which is perforated between the parallel lines 2,2 so that a pair of opposite marginal portions 3,3 are left without perforations.
  • A piece of plastic foil or film 4 having a thickness of e.g. 25u and provided with a netting 5 on its lower surface, covers the perforated area of the metal sheet 1 and extends slightly therebeyond as indicated by the lines 6,6. The netting 5 is adhesively attached to both the plastic foil 4 and the metal sheet 1 and forms a layer of air-filled cells therebetween which are closed by the plastic foil or film but communicate with the surrounding air through the perforations of the metal sheet 1.

Claims (2)

1. A sound absorbing structure consisting of thin, perforated sheet material, such as aluminium or steel sheet, and a foil secured to one side of said sheet, preferably a plastic foil having a thickness of about 10-50p, characterized in that between its securing points the foil is spaced a distance from the sheet material which is optimum as far as sound,absorption is concerned.
2. A structure according to claim 1, characterized in that a netting is sandwiched between the sheet material and the foil and by glueing or welding is attached to the sheet material as well as to the foil, said netting having a mesh size of the order of 1-5 mm.
EP79303073A 1979-01-04 1979-12-28 Sound absorbing structure Expired EP0013513B1 (en)

Priority Applications (1)

Application Number Priority Date Filing Date Title
AT79303073T ATE9017T1 (en) 1979-01-04 1979-12-28 SOUNDPROOF STRUCTURE.

Applications Claiming Priority (2)

Application Number Priority Date Filing Date Title
DK4379A DK4379A (en) 1979-01-04 1979-01-04 SOUND ABSORPTION UNIT
DK43/79 1979-01-04

Publications (2)

Publication Number Publication Date
EP0013513A1 true EP0013513A1 (en) 1980-07-23
EP0013513B1 EP0013513B1 (en) 1984-08-15

Family

ID=8089085

Family Applications (1)

Application Number Title Priority Date Filing Date
EP79303073A Expired EP0013513B1 (en) 1979-01-04 1979-12-28 Sound absorbing structure

Country Status (11)

Country Link
EP (1) EP0013513B1 (en)
JP (1) JPS5592446A (en)
AT (1) ATE9017T1 (en)
AU (1) AU533557B2 (en)
DE (1) DE2967185D1 (en)
DK (1) DK4379A (en)
EG (1) EG14896A (en)
ES (1) ES256657Y (en)
FI (1) FI800007A (en)
MX (1) MX149377A (en)
NO (1) NO794220L (en)

Cited By (10)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
GB2133431A (en) * 1982-11-20 1984-07-25 Hans Julius Schmitt A sound-proofing building element
EP0445431A2 (en) * 1990-03-09 1991-09-11 G + H Montage Gmbh Resonator screen for a sound damping screen
US5192624A (en) * 1990-04-26 1993-03-09 Unix Corporation Ltd. Sound absorbing materials
GB2264895A (en) * 1992-03-13 1993-09-15 Toru Morimoto Membranous sound-absorbing materials
EP0615032A1 (en) * 1993-03-03 1994-09-14 EUROFIBRE S.p.A. Thermally insulating and sound absorbent panel
WO2001071116A1 (en) 2000-03-20 2001-09-27 Newmat, S.A. Flexible sheet fabrics for tensile structures, method for making same, tensile false ceilings comprising same
US7445828B2 (en) 2003-08-18 2008-11-04 Silu Verwaltung Ag Assembly tape with sectional protective film
FR2926099A1 (en) * 2008-01-09 2009-07-10 Normalu Soc Par Actions Simpli COVER FOR ACCOUSTIC TIGHTS SEALED AND PARTIALLY TRANSLUCENT
EP2472018A1 (en) * 2010-12-30 2012-07-04 Normalu Acoustically absorbing assembly
WO2018206998A1 (en) * 2017-05-08 2018-11-15 Kvadrat Soft Cells A/S Building panel adapted to be mounted at a ceiling or wall of a room and method of manufacturing such building panel

Citations (3)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US2192653A (en) * 1937-11-13 1940-03-05 Schenk Eduard Acoustic construction
US2966954A (en) * 1957-07-11 1961-01-03 Celotex Corp Acoustical correction element
US3948347A (en) * 1974-11-25 1976-04-06 Gallagher-Kaiser Corporation Acoustical panel

Family Cites Families (2)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US3821999A (en) * 1972-09-05 1974-07-02 Mc Donnell Douglas Corp Acoustic liner
JPS5719759Y2 (en) * 1976-01-28 1982-04-26

Patent Citations (3)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US2192653A (en) * 1937-11-13 1940-03-05 Schenk Eduard Acoustic construction
US2966954A (en) * 1957-07-11 1961-01-03 Celotex Corp Acoustical correction element
US3948347A (en) * 1974-11-25 1976-04-06 Gallagher-Kaiser Corporation Acoustical panel

Cited By (17)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
GB2133431A (en) * 1982-11-20 1984-07-25 Hans Julius Schmitt A sound-proofing building element
EP0445431A2 (en) * 1990-03-09 1991-09-11 G + H Montage Gmbh Resonator screen for a sound damping screen
EP0445431A3 (en) * 1990-03-09 1992-10-21 G + H Montage Gmbh Resonator screen for a sound damping screen
US5192624A (en) * 1990-04-26 1993-03-09 Unix Corporation Ltd. Sound absorbing materials
GB2264895A (en) * 1992-03-13 1993-09-15 Toru Morimoto Membranous sound-absorbing materials
GB2264895B (en) * 1992-03-13 1996-01-10 Toru Morimoto Membranous sound-absorbing materials
US5545861A (en) * 1992-03-13 1996-08-13 Toru Morimoto Membranous-vibration sound absorbing materials
EP0615032A1 (en) * 1993-03-03 1994-09-14 EUROFIBRE S.p.A. Thermally insulating and sound absorbent panel
WO2001071116A1 (en) 2000-03-20 2001-09-27 Newmat, S.A. Flexible sheet fabrics for tensile structures, method for making same, tensile false ceilings comprising same
US7445828B2 (en) 2003-08-18 2008-11-04 Silu Verwaltung Ag Assembly tape with sectional protective film
FR2926099A1 (en) * 2008-01-09 2009-07-10 Normalu Soc Par Actions Simpli COVER FOR ACCOUSTIC TIGHTS SEALED AND PARTIALLY TRANSLUCENT
EP2078796A1 (en) 2008-01-09 2009-07-15 Normalu Cloth for watertight acoustic and partially translucid stretched walls
EP2472018A1 (en) * 2010-12-30 2012-07-04 Normalu Acoustically absorbing assembly
FR2970009A1 (en) * 2010-12-30 2012-07-06 Normalu ACOUSTICALLY ABSORBENT ASSEMBLY
WO2018206998A1 (en) * 2017-05-08 2018-11-15 Kvadrat Soft Cells A/S Building panel adapted to be mounted at a ceiling or wall of a room and method of manufacturing such building panel
KR20200028888A (en) * 2017-05-08 2020-03-17 크바드라트 소프트 셀스 에이/에스 Architectural panels configured to be mounted on the ceiling or wall of a room and how to manufacture such architectural panels
US11091909B2 (en) 2017-05-08 2021-08-17 Kvadrat Soft Cells A/S Building panel adapted to be mounted at a ceiling or wall of a room and method of manufacturing such building panel

Also Published As

Publication number Publication date
AU5426880A (en) 1980-07-10
JPS6310258B2 (en) 1988-03-04
ATE9017T1 (en) 1984-09-15
NO794220L (en) 1980-07-07
EP0013513B1 (en) 1984-08-15
JPS5592446A (en) 1980-07-12
ES256657U (en) 1981-07-01
AU533557B2 (en) 1983-12-01
MX149377A (en) 1983-10-28
DK4379A (en) 1980-07-05
DE2967185D1 (en) 1984-09-20
EG14896A (en) 1986-12-30
FI800007A (en) 1980-07-05
ES256657Y (en) 1981-12-16

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