US3756346A - Acoustical panel - Google Patents

Acoustical panel Download PDF

Info

Publication number
US3756346A
US3756346A US00268475A US3756346DA US3756346A US 3756346 A US3756346 A US 3756346A US 00268475 A US00268475 A US 00268475A US 3756346D A US3756346D A US 3756346DA US 3756346 A US3756346 A US 3756346A
Authority
US
United States
Prior art keywords
yarns
yarn
core yarn
core
woven
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.)
Expired - Lifetime
Application number
US00268475A
Other languages
English (en)
Inventor
L Burbank
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.)
BP Chemicals Hitco Inc
Original Assignee
BP Chemicals Hitco Inc
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 BP Chemicals Hitco Inc filed Critical BP Chemicals Hitco Inc
Application granted granted Critical
Publication of US3756346A publication Critical patent/US3756346A/en
Anticipated expiration legal-status Critical
Expired - Lifetime legal-status Critical Current

Links

Images

Classifications

    • 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
    • E04B1/86—Sound-absorbing elements slab-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
    • E04B2001/8423—Tray or frame type panels or blocks, with or without acoustical filling
    • 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
    • Y—GENERAL TAGGING OF NEW TECHNOLOGICAL DEVELOPMENTS; GENERAL TAGGING OF CROSS-SECTIONAL TECHNOLOGIES SPANNING OVER SEVERAL SECTIONS OF THE IPC; TECHNICAL SUBJECTS COVERED BY FORMER USPC CROSS-REFERENCE ART COLLECTIONS [XRACs] AND DIGESTS
    • Y10—TECHNICAL SUBJECTS COVERED BY FORMER USPC
    • Y10T—TECHNICAL SUBJECTS COVERED BY FORMER US CLASSIFICATION
    • Y10T428/00—Stock material or miscellaneous articles
    • Y10T428/24—Structurally defined web or sheet [e.g., overall dimension, etc.]
    • Y10T428/24174—Structurally defined web or sheet [e.g., overall dimension, etc.] including sheet or component perpendicular to plane of web or sheet
    • Y10T428/24182—Inward from edge of web or sheet
    • Y—GENERAL TAGGING OF NEW TECHNOLOGICAL DEVELOPMENTS; GENERAL TAGGING OF CROSS-SECTIONAL TECHNOLOGIES SPANNING OVER SEVERAL SECTIONS OF THE IPC; TECHNICAL SUBJECTS COVERED BY FORMER USPC CROSS-REFERENCE ART COLLECTIONS [XRACs] AND DIGESTS
    • Y10—TECHNICAL SUBJECTS COVERED BY FORMER USPC
    • Y10T—TECHNICAL SUBJECTS COVERED BY FORMER US CLASSIFICATION
    • Y10T428/00—Stock material or miscellaneous articles
    • Y10T428/30—Self-sustaining carbon mass or layer with impregnant or other layer

Definitions

  • An acoustical panel as disclosed, comprises a woven ABSTRACT fabric having internal ribs integrally woven with opposite planar faces so as to form compartments which trap and dissipate sound wave energy passed by at least one of the faces.
  • At least one of the faces, and in some cases selected ones of the internal ribs, are provided with a controlled porosity by being woven of combination yarns, each of which comprises a low-twist core yarn and at least one other low-twist yarn wound around the core yam.
  • the yarns which are wound around the core yarns prevent the core yarns from flattening excessively during weaving and subsequent resin impregnation and thereby prevent the resin from filling the voids between yarns.
  • each combination yarn is comprised of a core yarn of fiberglass or other appropriate material having a smaller yam of nylon or other appropriate material served thereon.
  • each combination yarn comprises a plurality of yarns braided onto the outside of a larger core yarn.
  • the present invention relates to acoustical panels, and particularly to acoustical panels of the type comprising a three-dimensional, integrally woven, resin impregnated fabric.
  • acoustical panels typically have a plurality of internal ribs which are integrally woven with opposite faces so as to form compartments therein. At least one of the faces, and in some cases selected ones of the ribs, are provided with a plurality of apertures appropriately dimensioned and configured so as to admit. and thereby trap sound waves within the compartments from outside the face.
  • the apertures within the various plies of the acoustical panel play a key role in its sound deadening capabilities.
  • the face must be provided with a sufficient number of apertures to be of sufficient size so as to pass a considerable volume of sound waves to the inside compartments for dissipation.
  • the face as well as the other portions of the acoustical panel must have the necessary strength and rigidity so as to be useful for the particular applications in question.
  • a common problem in making a panel which is rigid and strong and .yet adequately apertured arises from the fact that the yarns used to weave the faces and the interconnecting ribs of such fabrics undergo considerable flattening during weaving of the fabric and during subsequent resin impregnationthereof.
  • Such yarns are typically comprised of a plurality of fibers or filaments which have been twisted a few turns per inch to form low-twist yarns.
  • a yarn I which is initially generally circular in cross-section and of 0.0l0 inch diameter will be flattened so as to have a width on the order of 0.620 inch upon completion of the weaving.
  • the yarns which are subjected to elevated pressures as well as temperatures tend to undergo even further flattening against mandrels inserted therein.
  • the spaces between adjacent yarns in the fabric become extremely small, and during resin impregnation the resin tends to flow over and enclwe such spaces.
  • the present invention eliminates many of the prob lems of the prior art noted above in providing a wover fabric acoustical panel having porbus portions thereol which resist flattening while at the same time providing a suitable fabric density in terms of number of yarns per inch.
  • at least one face and in some cases selected ones of the ribs are woven of combination yarns, each of which comprises a core yarn and at least one other yamwound about the core yarn.
  • a yarn of selected composition and size is served onto a core yarn of typically greater size and appropriate composition.
  • a plurality of yarns of appropriate thickness and composition are braided on the outside of a core yarn of considerably larger diameter and of appropriate composition.
  • the serving or braiding of small, low-twist yarns on the outside of a larger low-twist core yarn greatly resists flattening of the core yarn during weaving and during suuent resin impregnation and curing. At the same time the slight increase in the overall density of the core yarn is not so great as to resist a thorough impregnation thereof by the resin.
  • the serving or braiding of the core yarns may be accomplished using conventional equipment for this purpose so as to in many cases provide a combination yarn of desired characteristics at a minimum of time and expense.
  • Serving or braiding in accordance with the invention is particularly well suited to fragile yams such as those comprised of carboaaceous materials, making practical the use of such yarns as the core yarns in woven fabric acoustical panels.
  • H6. 1 is a perspective view of a portion of a woven fabric acoustical panel in accordance with the invention
  • H6. 2 is a plan view of a portion of the face of the panel of FIG. I showing a pattern of apertures formed therein;
  • FIGS. 3A-3C are cross-sectional illustrations of a plurality of yarns during the different states of manufacture of the panel of FIG. 1 illustrating the advantages of the invention
  • FIG. 4 is a perspective view of a length of core yarn being served in accordance with the invention.
  • FEG. 5 is aperspective view of a length of core yarn being braided in accordance with the invention.
  • FIG. I illustrates a portion of an acoustical panel which includes upper and lower generally parallel faces 12 and 14 respectively and a plurality of interconnecting rihs 16.
  • the faces 12 and 14 are generally planar, sheet-like elements integrally woven with the ribs 16.
  • the ribs I6 are parallel to one anomer and extend between and join the faces 12 and 14.
  • selected portions of the panel which may include the upper face I2 and in some cases some or all of the ribs 1'5 have a plurality of apertures which extend therethrough and which serve to pass sound waves into and between internal cements 18 formed by the ribs 16 and the faces I2 and 14.
  • the faces 12 and I4 and the ribs 16 are comprised of an integrally woven fabric which is resin impreghated and cured for strength and rigidity.
  • Integrally woven fabrics of this general configuration as well as the techniques and materials used to resin impregnate and cure them are well known in the art.
  • One example of such a fabric and the technique for weaving the same is disclosed in U. S. Pat. No. 3,538,957, Rheaume, issued Nov. 10, I970.
  • FIG. 2 A portion of the upper face 12 of the acoustical panel 10 is illustrated in FIG. 2.
  • the face I2 includes a plurality of warp yarns 20 ii rwoven with a plurality of fill yarns 22 in convention fashion.
  • the face 12 is provided with a sufficient number of the 4 yarns 20 or 22 per inch thereof so as to achieve a satisfactory density.
  • the weave of the face I2 is loose enough so as to define a plurality of apertures 24 between the various warp and fill yarns 20 and 22.
  • the fabric portion illustrated in FIG. 2 could also comprise part of the bottom face 14 or the ribs I6 which are similarly interwoven from warp and fill yarns.
  • the warp yarns 20 and the fill yarns 22 undergo considerable fiattening. This greatly reduces the size of the resulting apertures 24.
  • the various yarns 20 and 22 are thereafter impregnated with resin and cured the resulting pressure increase which typically accompanies the curing process may cause even further flattening of the yarns 20 and 22 against mandrels inserted in the compartments 18 so as to reduce the size of the apertures 24. If the apertures 24 become too small the resin tends to cover over and thereby enclose most or all of the apertures 24, rendering the panel 10 useless for acoustical purposes.
  • the various yarns 20 and 22 are comprised of a plurality of low-twist yarns which are interwound such as by serving or braiding so as to substantially resist flattening of the yarns during weaving and subsequent resin impregnation and curing while at the same time maintaining the density of the individual yarns at a sufficiently low level so as to readily accept or absorp the resin during the impregnation process.
  • FIG. 3A depicts in cross-section four of the warp yarns 20 as they might be positioned relative to one another at the start of the weaving process. While in actual practice the yarns which are made up of plural fibers or filaments are generally other than perfectly circular in cross-section, the various yarns 20 are assumed to be perfectly circular in cross-section and to have a diameter of 0.010 inch for purposes of the present example. In addition the various yarns 20 are assumed to be separated from adjacent yarns by distances very slightly greater than their 0.010 inch diameters.
  • FEG. 3B depicts the amount of flattening of the yarns 20 which is typically present at the end of the weaving process where low-twist yarns are used.
  • the various yarns 20 have dimensions in the plane of the cloth which are on the order of 0.020 inch or approximately twice the diameters of the various yarns 2% prior to weaving.
  • the resulting apertures 24 between the yarns 20 are of very small size and may even be nonexistent between some of the yarns.
  • the yarns 20 are thereafter resin impregnated and cured the resin will typically fill the apertures 24 in the example of FIG. 38, resulting in a fabric having an insumcient number of the apertures 24 of adequate size to be useful as an acoustical panel. '1
  • the various yams 20 are assumed to be low-twist yams which have been twisted approximately I to 4 turns per inch of length thereof.
  • FIG. 3C depicts the results when the various yarns 20 comprise served or braided yarns in accordance with the invention. As seen in FIG. 3C the various yarns 20 undergo some flattening during weaving and curing but new;
  • yarns 20 which initially have diameters on the order of 0.010 inch as shown in FIG. 3A are typically flattened to the extent that the dimensions of such yarns within the plane of the cloth are on the order of 0.015 inch after weaving, impregnation and curing. As will be seen this leaves the cloth with apertures 24 of sufficient size so as to pennit resin impregnation and curing without severely reducing the size of or eliminating the apertures 24.
  • FIG. 4 depicts a portion of the yarn which is being served for use as the warp yarns 20 and the fill yarns 22.
  • a sewing yarn 26 is wrapped around or served on the outside of a core yarn 28.
  • core yarn 28 which is typically on the order of about 0.0l0-0.030 inch thick may be comprised of fiberglass. carbon or any other suitable material.
  • the serving yarn 26 which typically has a diameter considerably smaller than that of the core yarn 28 may be made of any appropriate material such as nylon or Dacron of approximately 30-200 denier. The serving yarn 26 is served onto the core yarn 28 using conventional techniques at an appropriate speed and at an appropriate tension so as to greatly increase the resistance of the yarn to flattening while at the same time making the yarn porous enough toaccept the resin during impregnation.
  • yarns 26 of the type typically used as described above may be served on the core yarns 28 of the type described above at a rate on the order of 5-15 turns of the serving yarn 26 per inch of length of the core yarn 28 with satisfactory results.
  • Serving at a rate lower than 5 turns per inch produces a combination yarn which may undergo excessive flattening.
  • serving at greater than turns per inch typically produces a combination yarn which has more than adequate resistance to flattening but which is too densely bound to properly receive the resin during impregnation.
  • FIG. 5 depicts an alternative technique of preparing the yarns and 22 in accordance with the invention.
  • a plurality of braiding yarns 30 are braided onto the outside of a core yarn 32 using any of a number of braiding techniques known in the art.
  • the braiding yarns 30 are of considerably smaller diameter than the core yarn 32 and may comprise, for exampie, fibers of approximately the same I time have adequate resistance to flattening.
  • the techniques of the present invention are particularly advantageous over those of the prior art where relatively fragile yarns are used.
  • relatively fragile yarns are used.
  • the processing of yarns of this type into a high twist state frequently produces a yarn too fragile for successful weaving.
  • the present invention produces greatly improved results.
  • the techniques of the present invention do not damage or destroy the fragile yarns through twisting or undesirable operations.
  • the serving or 6 braiding of more durable yarns onto the outside of the fragile yarns greatly increases the resistance of the fragile yarns to abrasion during the weaving process. This is particularly true of the braiding technique of FIG. 5 which covers enough of the outside surface of the core yam so as to greatly resist abrasion of a core yarn of fragile or easily abraided composition.
  • the various ribs 16 are generally parallel with each other and form compartments 18 of generally rectangular cross-section.
  • other fabric configurations can be used in accordance with the invention such as those in which the internal ribs extend in zig zag fashion between the op posite faces so as to form compartments of generally triangular cross-section.
  • one of the faces such as the upper face I2, and in some cases selected ones of the ribs 16, have a degree of openness such as is provided by the invention. This is accomplished in accordance with the invention by weaving such parts of served or braided yarns. By the same token it may be necessary or desirable that other parts of the fabric such as the bottom face 14 and the remaining ribs I6 be generally impervious to sound such as by providing them with little or no openings. This can be accomplished using any of a number of appropriate techniques. One such technique is to use conventional low-twist yarns to the extent possible in weaving those parts which are not to be porous.
  • conventional low-twist yarns which have been neither served nor braided in accordance with the invention are used as both the warp yarns and the fill yarns of the face 14. Such yarns undergo substantial flattening so as to produce little or no porosity in the finished product..Sirnilar considerations apply to the ribs where at least the till yarns and in some cases the warp yarns of those ribs to be formed with little or not porosity are comprised of conventional low-twist yarns.
  • An acoustical panel comprising a woven fabric having a generally planar face portion and a plurality of internal rib portions integraily woven with and extending-from the face portion to form acoustical compartments within the fabric, at least the face portion being woven'of combination yarns, each of which comprises a core yarn and at least one other yarn wound around the core yarn.
  • each of the combination yarns comprises a core yam having a serving yarn served about the outside thereof.
  • each of the combination yarns comprises a core yarn having a plurality of braiding yarns braided about the outside thereof.
  • each of the core yarns has between 1 and 4 twists per inch of length thereof.
  • serving yarn has a diameter considerably smaller than the diameter of the core yarn and is served on the core length of the core yarn.
  • the core yarn comprises fiberglass having a diameter between 0.0l0 inch and 0.030 inch and the serving yarr comprises nylon of between 30 and 200 denier.
  • An acoustical panel comprising a woven fabric having generally planar front and back face portion: and a plurality of rib portions integrally woven with and extending between the front and back face portions, a1 least a portion of the fabric being woven of yams, each of which comprises a core yarn and a plurality of braiding yarns braided onto the outside of the core yarn.

Landscapes

  • Physics & Mathematics (AREA)
  • Acoustics & Sound (AREA)
  • Engineering & Computer Science (AREA)
  • Architecture (AREA)
  • Electromagnetism (AREA)
  • Civil Engineering (AREA)
  • Structural Engineering (AREA)
  • Soundproofing, Sound Blocking, And Sound Damping (AREA)
  • Building Environments (AREA)
  • Laminated Bodies (AREA)
US00268475A 1972-07-03 1972-07-03 Acoustical panel Expired - Lifetime US3756346A (en)

Applications Claiming Priority (1)

Application Number Priority Date Filing Date Title
US26847572A 1972-07-03 1972-07-03

Publications (1)

Publication Number Publication Date
US3756346A true US3756346A (en) 1973-09-04

Family

ID=23023170

Family Applications (1)

Application Number Title Priority Date Filing Date
US00268475A Expired - Lifetime US3756346A (en) 1972-07-03 1972-07-03 Acoustical panel

Country Status (4)

Country Link
US (1) US3756346A (enrdf_load_html_response)
JP (1) JPS4964217A (enrdf_load_html_response)
FR (1) FR2237560A5 (enrdf_load_html_response)
GB (1) GB1430448A (enrdf_load_html_response)

Cited By (6)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US3960236A (en) * 1974-06-17 1976-06-01 Mcdonnell Douglas Corporation Lock core panel
US3966522A (en) * 1974-05-23 1976-06-29 Hitco Method of making woven acoustical panel
US4600619A (en) * 1984-12-31 1986-07-15 The Boeing Company Continuously wound filament structure for use in noise attenuation element
US5166480A (en) * 1988-04-23 1992-11-24 Vorwerk & Co. Interholding Gmbh Knitted fabric panel structure and process of manufacture
US5240533A (en) * 1987-07-17 1993-08-31 Vorwerk & Co. Interholding Gmbh Method of fabricating a structural element formed of a resin-hardened velour fabric
US11485048B2 (en) * 2012-10-23 2022-11-01 Albany Engineered Composites, Inc. Circumferential stiffeners for composite fancases

Families Citing this family (2)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
FR2480741A1 (fr) * 1980-04-18 1981-10-23 Aerospatiale Couche poreuse pour structure composite destinee a l'absorption d'energie sonore et son procede de fabrication
GB9001358D0 (en) * 1990-01-20 1990-05-30 Scapa Group Plc Deformable fabric for composite materials

Citations (7)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US3147820A (en) * 1955-01-25 1964-09-08 Johns Manville Acoustical panel unit with porous resinous facing
US3231042A (en) * 1961-06-28 1966-01-25 Mohasco Ind Inc Foldable sound insulating material and partition
US3481427A (en) * 1968-11-29 1969-12-02 Mc Donnell Douglas Corp Acoustical panel structure
US3502171A (en) * 1968-05-31 1970-03-24 Boeing Co Composite laminar structure for noise attenuation of fast moving gas streams,and method of making the same
US3565127A (en) * 1968-10-22 1971-02-23 Monsanto Co Inextensible filamentary structures, and fabrics woven therefrom
US3631667A (en) * 1967-08-29 1972-01-04 Owens Corning Fiberglass Corp Method of making reinforcement for tires
US3700067A (en) * 1970-06-01 1972-10-24 Mc Donnell Douglas Corp Acoustic face sheet

Patent Citations (7)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US3147820A (en) * 1955-01-25 1964-09-08 Johns Manville Acoustical panel unit with porous resinous facing
US3231042A (en) * 1961-06-28 1966-01-25 Mohasco Ind Inc Foldable sound insulating material and partition
US3631667A (en) * 1967-08-29 1972-01-04 Owens Corning Fiberglass Corp Method of making reinforcement for tires
US3502171A (en) * 1968-05-31 1970-03-24 Boeing Co Composite laminar structure for noise attenuation of fast moving gas streams,and method of making the same
US3565127A (en) * 1968-10-22 1971-02-23 Monsanto Co Inextensible filamentary structures, and fabrics woven therefrom
US3481427A (en) * 1968-11-29 1969-12-02 Mc Donnell Douglas Corp Acoustical panel structure
US3700067A (en) * 1970-06-01 1972-10-24 Mc Donnell Douglas Corp Acoustic face sheet

Cited By (6)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US3966522A (en) * 1974-05-23 1976-06-29 Hitco Method of making woven acoustical panel
US3960236A (en) * 1974-06-17 1976-06-01 Mcdonnell Douglas Corporation Lock core panel
US4600619A (en) * 1984-12-31 1986-07-15 The Boeing Company Continuously wound filament structure for use in noise attenuation element
US5240533A (en) * 1987-07-17 1993-08-31 Vorwerk & Co. Interholding Gmbh Method of fabricating a structural element formed of a resin-hardened velour fabric
US5166480A (en) * 1988-04-23 1992-11-24 Vorwerk & Co. Interholding Gmbh Knitted fabric panel structure and process of manufacture
US11485048B2 (en) * 2012-10-23 2022-11-01 Albany Engineered Composites, Inc. Circumferential stiffeners for composite fancases

Also Published As

Publication number Publication date
GB1430448A (en) 1976-03-31
FR2237560A5 (enrdf_load_html_response) 1975-02-07
JPS4964217A (enrdf_load_html_response) 1974-06-21

Similar Documents

Publication Publication Date Title
US4257835A (en) Method of manufacture of material reinforced with a three-dimensional textile structure
US4680213A (en) Textile reinforcement used for making laminated complexes, and novel type of laminate comprising such a reinforcement
US5939338A (en) Warp and weft fabric based on predominantly untwisted multifilament technical threads and method for producing same
US5465760A (en) Multi-layer three-dimensional fabric and method for producing
US3645833A (en) Article and method of quasi-isotropic core filaments
US4001478A (en) Three-dimensional fabric material
US3966522A (en) Method of making woven acoustical panel
RU2518378C2 (ru) Волокнистый композиционный материал и способ его изготовления
JPS6468536A (en) Fabric structure for production of laminate having high mechanical strength
US4038440A (en) Three dimensional fabric material
US6447886B1 (en) Base material for a printed circuit board formed from a three-dimensional woven fiber structure
US3943980A (en) Multi-ply woven article having double ribs
US3955602A (en) Apparatus for fabricating three-dimensional fabric material
US3756346A (en) Acoustical panel
Mohamed Three-dimensional textiles
US4103055A (en) Porous structure
US5270094A (en) Three-dimensional fabric with symmetrically arranged warp and bias yarn layers
US10023981B2 (en) 3D woven preforms with channels
JPH0781225B2 (ja) 結合部材用三次元織物
US4976550A (en) Expanded fiber-reinforced bearings
US5358767A (en) Textile structure useful as reinforcements in the manufacture of composite materials, and technical yarns for such structures
CN107956024A (zh) 一种梯度结构三维织物及其制备方法
US5154965A (en) Deformable fabric for composite materials
US3966013A (en) Multi-ply woven article having acoustical elements between double plies
KR900000523A (ko) 다수의 날실층과 씨실층을 갖는 직물 및 이의 제조방법