GB2025925A - Structural material for acoustic machines and instruments - Google Patents

Structural material for acoustic machines and instruments Download PDF

Info

Publication number
GB2025925A
GB2025925A GB7923241A GB7923241A GB2025925A GB 2025925 A GB2025925 A GB 2025925A GB 7923241 A GB7923241 A GB 7923241A GB 7923241 A GB7923241 A GB 7923241A GB 2025925 A GB2025925 A GB 2025925A
Authority
GB
United Kingdom
Prior art keywords
instruments
structural material
rubber
acoustic
ceramic
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
GB7923241A
Other versions
GB2025925B (en
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.)
Aikoh Co Ltd
Original Assignee
Aikoh Co Ltd
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 Aikoh Co Ltd filed Critical Aikoh Co Ltd
Publication of GB2025925A publication Critical patent/GB2025925A/en
Application granted granted Critical
Publication of GB2025925B publication Critical patent/GB2025925B/en
Expired legal-status Critical Current

Links

Classifications

    • C—CHEMISTRY; METALLURGY
    • C04—CEMENTS; CONCRETE; ARTIFICIAL STONE; CERAMICS; REFRACTORIES
    • C04B—LIME, MAGNESIA; SLAG; CEMENTS; COMPOSITIONS THEREOF, e.g. MORTARS, CONCRETE OR LIKE BUILDING MATERIALS; ARTIFICIAL STONE; CERAMICS; REFRACTORIES; TREATMENT OF NATURAL STONE
    • C04B41/00—After-treatment of mortars, concrete, artificial stone or ceramics; Treatment of natural stone
    • C04B41/009—After-treatment of mortars, concrete, artificial stone or ceramics; Treatment of natural stone characterised by the material treated
    • C—CHEMISTRY; METALLURGY
    • C04—CEMENTS; CONCRETE; ARTIFICIAL STONE; CERAMICS; REFRACTORIES
    • C04B—LIME, MAGNESIA; SLAG; CEMENTS; COMPOSITIONS THEREOF, e.g. MORTARS, CONCRETE OR LIKE BUILDING MATERIALS; ARTIFICIAL STONE; CERAMICS; REFRACTORIES; TREATMENT OF NATURAL STONE
    • C04B26/00—Compositions of mortars, concrete or artificial stone, containing only organic binders, e.g. polymer or resin concrete
    • C04B26/02—Macromolecular compounds
    • C—CHEMISTRY; METALLURGY
    • C04—CEMENTS; CONCRETE; ARTIFICIAL STONE; CERAMICS; REFRACTORIES
    • C04B—LIME, MAGNESIA; SLAG; CEMENTS; COMPOSITIONS THEREOF, e.g. MORTARS, CONCRETE OR LIKE BUILDING MATERIALS; ARTIFICIAL STONE; CERAMICS; REFRACTORIES; TREATMENT OF NATURAL STONE
    • C04B38/00—Porous mortars, concrete, artificial stone or ceramic ware; Preparation thereof
    • C04B38/0051—Porous mortars, concrete, artificial stone or ceramic ware; Preparation thereof characterised by the pore size, pore shape or kind of porosity
    • C—CHEMISTRY; METALLURGY
    • C04—CEMENTS; CONCRETE; ARTIFICIAL STONE; CERAMICS; REFRACTORIES
    • C04B—LIME, MAGNESIA; SLAG; CEMENTS; COMPOSITIONS THEREOF, e.g. MORTARS, CONCRETE OR LIKE BUILDING MATERIALS; ARTIFICIAL STONE; CERAMICS; REFRACTORIES; TREATMENT OF NATURAL STONE
    • C04B41/00—After-treatment of mortars, concrete, artificial stone or ceramics; Treatment of natural stone
    • C04B41/45—Coating or impregnating, e.g. injection in masonry, partial coating of green or fired ceramics, organic coating compositions for adhering together two concrete elements
    • C04B41/46—Coating or impregnating, e.g. injection in masonry, partial coating of green or fired ceramics, organic coating compositions for adhering together two concrete elements with organic materials
    • C04B41/48—Macromolecular compounds
    • C—CHEMISTRY; METALLURGY
    • C04—CEMENTS; CONCRETE; ARTIFICIAL STONE; CERAMICS; REFRACTORIES
    • C04B—LIME, MAGNESIA; SLAG; CEMENTS; COMPOSITIONS THEREOF, e.g. MORTARS, CONCRETE OR LIKE BUILDING MATERIALS; ARTIFICIAL STONE; CERAMICS; REFRACTORIES; TREATMENT OF NATURAL STONE
    • C04B41/00—After-treatment of mortars, concrete, artificial stone or ceramics; Treatment of natural stone
    • C04B41/80—After-treatment of mortars, concrete, artificial stone or ceramics; Treatment of natural stone of only ceramics
    • C04B41/81—Coating or impregnation
    • C04B41/82—Coating or impregnation with organic materials
    • C04B41/83—Macromolecular compounds
    • 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
    • G10K11/162—Selection of materials
    • G—PHYSICS
    • G11—INFORMATION STORAGE
    • G11B—INFORMATION STORAGE BASED ON RELATIVE MOVEMENT BETWEEN RECORD CARRIER AND TRANSDUCER
    • G11B19/00—Driving, starting, stopping record carriers not specifically of filamentary or web form, or of supports therefor; Control thereof; Control of operating function ; Driving both disc and head
    • G11B19/20—Driving; Starting; Stopping; Control thereof
    • G11B19/2009—Turntables, hubs and motors for disk drives; Mounting of motors in the drive
    • G—PHYSICS
    • G11—INFORMATION STORAGE
    • G11B—INFORMATION STORAGE BASED ON RELATIVE MOVEMENT BETWEEN RECORD CARRIER AND TRANSDUCER
    • G11B33/00—Constructional parts, details or accessories not provided for in the other groups of this subclass
    • G11B33/02—Cabinets; Cases; Stands; Disposition of apparatus therein or thereon
    • G11B33/08—Insulation or absorption of undesired vibrations or sounds

Landscapes

  • Chemical & Material Sciences (AREA)
  • Engineering & Computer Science (AREA)
  • Ceramic Engineering (AREA)
  • Materials Engineering (AREA)
  • Structural Engineering (AREA)
  • Organic Chemistry (AREA)
  • Multimedia (AREA)
  • Acoustics & Sound (AREA)
  • Physics & Mathematics (AREA)
  • Details Of Audible-Bandwidth Transducers (AREA)
  • Porous Artificial Stone Or Porous Ceramic Products (AREA)
  • Soundproofing, Sound Blocking, And Sound Damping (AREA)
  • Compositions Of Oxide Ceramics (AREA)
  • Powder Metallurgy (AREA)
  • Holding Or Fastening Of Disk On Rotational Shaft (AREA)
  • Compositions Of Macromolecular Compounds (AREA)
  • Ceramic Products (AREA)
  • Application Of Or Painting With Fluid Materials (AREA)

Abstract

A structural material for acoustic machines and instruments comprises a sintered ceramic body wherein porosity is more than 20%, the pore diameter being less than 300 microns on average, and at least part of the pores is impregnated with rubber and/or resin.

Description

SPECIFICATION Structural material for acoustic machines and instruments This invention relates to an improvement in or relating to a structural material fo acoustic machines and instruments.
As the materials for turntable, turntable sheet, stabilizer, speaker enclosure, floor system enclosure, head shell and tone arm of acoustic machines and instruments, particularly of record player there were hitherto employed mainly metals such as aluminium die casting and press worked steel plate and wood in view of easy workability, rigidity and appearance to some extent, and moderate cost, in the hope that (1) said materials may have a great equivalent mass and a high rigidity so as to hardly vibrate, and that (2) they may have a great damping ratio to vibration thereby attenuating vibration quickly, said two features (1) and (2) being of properties of making acoustic effects good.
Among said products, however, the metallic ones have a very small damping ratio to vibration but a high resonance sharpness fh so that they have demerits in likelihood of resonance to specific frequency. They are liable to receive the vibration of motor, the outside vibration transmitted through player board and the vibration of speaker so as to deteriorate the signal-to-noise ratio, thereby causing sometimes howling. Wooden speaker enclosure is resonant even with specific resonance. To prevent this unfavorable effect there has ben provided means that the upper or lower face of a turntable is coated or adhered with a substance having a great damping ratio of vibration, such as resin or rubber, or it is stuck together with composite plastics.However, in the former case it is impossible to completely control the properties innate to the metallic body because the resin or rubber is a complement to the metallic body. To answer the purpose, therefore, the resin or rubber must be greater in mass than the metallic body whereby the rigidity of metal can no longer be effectively used. In the latter case the main skeleton is of plastics so that it lacks in rigidity and the turntable causes damping action to swing the disc up and down, while causing a fear of troubling the tracing operation of stylus chip. Further being light in weight with regard to plastics, its mass is small when the content of filler is less to lack in the inertia mass of said turntable thereby causing wow and flutter as in a turntable of metal plate. Furthermore, wooden articles have a great damping ratio but they come short of rigidity.
The object of the invention is to provide materials for acoustic machines and instruments of the kind described at the beginning of the specification, said machines and instruments excluding the conventional demerits and having good performance.
The turntable according to the invention consists of a sintered ceramic body wherein porosity is more than 20% and the diameter of the pores is less than 300 microns on an average, or a body wherein at least part of the pores of said sintered body is impregnated with elastic materials such as rubber and/or resin; or of a moulding wherein ceramic powder is bonded with resins and/or rubber and then the bonded powder is moulded, or a moulding wherein at least part thereof is impregnated with elastic materials such as rubber and/or resin. The great rigidity and mass possessed by ceramic may serve formless sensitivity against vibration of the turntable and for quickly. attenuating the vibration thanks to the pores of ceramic. In the ceramic fit for the material of the acoustic machines and instruments according to the invention, the greater in rigidity the better.However, the allowable lower limit of the rigidity will be a Knoop harness of more than 5000 to fall under a range in which the strain by vibration does not badly affects the sound effects.
This means that materials harder than ceramic or glass can be used. Further, preferably the ratio of the pores which attenuate the damping ratio of vibration as quickly as possible is more than 20% porosity, and the porosity of less than 20% will have less effect because it cannot sufficiently form pores included between crystal particles of ceramic in order to promptly decrease the vibration added to the ceramic body. Accordingly, the less in the size of pores the wider they disperse so that the pores can be included more between the crystals and particles of ceramic to increase the attenuating properties of inside vibration, but ceramic having an average pore diameter of less than 300 microns can satisfy these requirements.
Further, it is effective for increasing the damping ratio of vibration to impregnate the interior or the pores of ceramic having said pores with elastic substances such as rubber and/or resin in place of air. That is, the rubber or resin is active for enclosing the vibration which was subject to the crystals or particles of ceramic to be a rigid body, into the crystals or particles, thereby attenuating the vibration. The impregnation may not necessarily be carried out over the entire pores, and it may be restricted to the upper face lower face and middle portion of the material to be treated or non-uniformly dispersed in its entirety.
Advantageously, the turntable which is impregnated with rubber or resin at its upper face will not require a turntable sheet made of rubber.
As the ceramic used for the turntable of the invention there can also be employed, besides said sintered body, a moulding in which ceramic particles are moulded with binding agent such as resin, rubber or the like and then solidified. In this case, however, the whole moulding might lose rigidity if elastic layers of the binder are produced among the ceramic particles, so that the binder should be used as little as possible and practically the binder within 3% will be suitable.
Even in this case, the pores should be more than 20% in porosity and less than 300 microns in diameter as in said sintered ceramic. It is likewise possible to impregnate the pores with said elastic substance.
The invention will now be described more in detail, by way of examples, with reference to a turntable.
(1) SINTERED ARTICLES Ceramic material is added with kaolin of more than 10% and then wet mixed with a small amount of combustible material and water. The mixture is moulded by pressing such as under hydraulic pressure, air pressure, oil pressure or friction, and after drying it is sintesed in a sintering furnace. After cooling the sintered article, its surface is faced thereby grinding and processing it to a desired extent of preciseness of dimension and shape. The mixed combustible materials are effective for forming pores, and there are used wax, fine powder of wood, starch, wheat powder and the like.
Impregnation of the elastic substances may be carried out in a liquid state of said substances, such as latex of natural or artificial rubber besides a carbon dioxide solution of rubber, and alcohol solution of resin or the like, by either coating it onto the surface of turntable or dipping the turntable in it thereafter drying.
Mixing examples and the properties of the sintered pieces of ceramic produced with said mixing are now described hereunder.
(a) Alumina (250,u) 87% Kaolin 13% Porosity 32% Average pore diameter 150 y Bulk specific gravity 2.47 Hardness 22000 Knoop (b) Silicon carbide (125pal) 85% Kaolin 1 5% Porosity 31% Average pore diameter 45,u Bulk specific gravity 2.04 Hardness 24000 Knoop (2) MOULDINGS Ceramic powder is added with thermosetting resin such as phenol resin as a binder, and further with an oil wetting agent such as kerosene in case the binder is powdery. The mixture is kneaded and then compressed and moulded by means of pressing. The moulding is solidified in a soliditying chamber at a temperature in the range 1 50#1800 C, and after cooling, its surface is faced.The mixing examples are as follows: (a) Alumina { 250y \ 97.8% 22000 Knoop Phenol resin powder 2.0% Kerosene (vanished when heated) 0.2% Porosity 35% Average pore diameter 150,u Bulk specific gravity 2.25 (b) Silicon carbidetl25y 97.2% 24000 Phenol resin powder 2.5% Kerosene 0.3% Porosity 33%.
Average pore diameter 45y Bulk specific gravity 2.01 As a mode of working of the invention, a test listening was carried out by acoustic specialists by using a disc turntable in which a turntable sheet made of baked ceramic impregnated with silicon rubber was adhered onto a conventional turntable made of aluminium die casting, with an adhesive or the like. As a result, it was proved that compared with conventional aluminium die casting disc turntable with rubber sheet, there was scarcely resonance caused by mechanical vibration, sound effects of high damping effect were exerted, and acoustic properties thanks to the rigidity and porosity of ceramic are very prominent, said properties being a technical idea of the invention.

Claims (5)

1. A structural material for acoustic machines and instruments, which comprises a sintered ceramic body having a porosity of more than 20% with an average pore diameter of less than 300 microns.
2. A structural material for acoustic machines and instruments as claimed in Claim 1 wherein at least some of the pores are impregnated with rubber arid/or resin.
3. A structural material for acoustic machines and instruments, which comprises a ceramic moulding bonded with resin and/or rubber, said moulding having a porosity of more than 20% with an average pore diameter of less than 300 microns.
4. A structural material for acoustic machines and instruments as claimed in Claim 3 wherein at least some of the pores are impregnated with rubber and/or resin.
5. A composite structure material for acoustic machines and instruments wherein any structural material of Claim 1, 2, 3 or 4 is adhered with a conventional structural material for acoustic machines and instruments by means of an adhesive or the like.
6 A structural material for acoustic machines and instruments substantially as described in any one of the foregoing Examples.
GB7923241A 1978-07-20 1979-07-04 Structural material for acoustic machines and instruments Expired GB2025925B (en)

Applications Claiming Priority (1)

Application Number Priority Date Filing Date Title
JP8768578A JPS5515147A (en) 1978-07-20 1978-07-20 Structure material for sound equipment

Publications (2)

Publication Number Publication Date
GB2025925A true GB2025925A (en) 1980-01-30
GB2025925B GB2025925B (en) 1982-09-15

Family

ID=13921775

Family Applications (1)

Application Number Title Priority Date Filing Date
GB7923241A Expired GB2025925B (en) 1978-07-20 1979-07-04 Structural material for acoustic machines and instruments

Country Status (14)

Country Link
JP (1) JPS5515147A (en)
AU (1) AU525975B2 (en)
BE (1) BE877666A (en)
CA (1) CA1129269A (en)
DE (1) DE2927884C2 (en)
DK (1) DK304879A (en)
FR (1) FR2431742A1 (en)
GB (1) GB2025925B (en)
IN (1) IN151078B (en)
IT (1) IT1121187B (en)
LU (1) LU81531A1 (en)
NL (1) NL7905657A (en)
NO (1) NO152715C (en)
SE (1) SE7905653L (en)

Cited By (1)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
WO1997010426A1 (en) * 1995-09-13 1997-03-20 Nederlandse Organisatie Voor Toegepast-Natuurwetenschappelijk Onderzoek Tno Exhaust device for a turbine engine

Families Citing this family (8)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
JPS56169991A (en) * 1980-06-03 1981-12-26 Onkyo Corp Member for acoustic device
JPS6232738Y2 (en) * 1980-12-21 1987-08-21
JPS6066182U (en) * 1983-10-13 1985-05-10 オンキヨー株式会社 speaker box
JPS6068780U (en) * 1983-10-15 1985-05-15 オンキヨー株式会社 speaker stand
JPS6068783U (en) * 1983-10-15 1985-05-15 オンキヨー株式会社 speaker cabinet
DE3581300D1 (en) * 1984-03-28 1991-02-21 Reinhard Friedrich Hering METHOD FOR THE ELASTOMER COATING OF MINERAL MATERIALS AND PRODUCT PRODUCED BY THIS METHOD.
EP0196865B1 (en) * 1985-03-27 1990-09-12 Ibiden Co, Ltd. Electronic circuit substrates
DE202013000358U1 (en) * 2013-01-15 2013-02-27 Rüdiger Wichmann Turntable pad for record player

Family Cites Families (6)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
DE1072543B (en) * 1959-12-31 Metallgesellschaft Aktiengesell schaft, Frankfurt/M Porous filter bodies and process for their manufacture
DE1027582B (en) * 1953-08-31 1958-04-03 Dynamidon Werk Engelhorn & Co Process for the production of highly refractory bricks
BE795941A (en) * 1972-03-03 1973-08-27 Siemens Ag HIGH POROSITY PERMEABLE CERAMIC SUPPORT, IN PARTICULAR FOR CATALYSTS AS WELL AS ITS PREPARATION PROCESS
JPS5265418A (en) * 1975-11-27 1977-05-30 Pioneer Electronic Corp Sound insulator
JPS52108111A (en) * 1976-03-08 1977-09-10 Sanyo Electric Co Ltd Diaphragm for speaker
DE2627912C3 (en) * 1976-06-22 1979-10-04 Institut Vysokich Temperatur Akademii Nauk Ssr, Moskau Porous high temperature construction material

Cited By (3)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
WO1997010426A1 (en) * 1995-09-13 1997-03-20 Nederlandse Organisatie Voor Toegepast-Natuurwetenschappelijk Onderzoek Tno Exhaust device for a turbine engine
NL1001183C2 (en) * 1995-09-13 1997-03-20 Tno Exhaust device for a turbine engine.
US6257366B1 (en) 1995-09-13 2001-07-10 Nederlandse Organisatie Voor Toegepast-Natuurwetenschappelijk Onderzoek Exhaust device for a turbine engine

Also Published As

Publication number Publication date
NO152715B (en) 1985-07-29
IT7909494A0 (en) 1979-07-19
IT1121187B (en) 1986-03-26
FR2431742B1 (en) 1984-09-07
DE2927884C2 (en) 1982-06-09
GB2025925B (en) 1982-09-15
NL7905657A (en) 1980-01-22
FR2431742A1 (en) 1980-02-15
SE7905653L (en) 1980-01-21
LU81531A1 (en) 1979-10-31
NO792386L (en) 1980-01-22
CA1129269A (en) 1982-08-10
DK304879A (en) 1980-01-21
IN151078B (en) 1983-02-19
NO152715C (en) 1985-11-13
AU525975B2 (en) 1982-12-09
JPS5515147A (en) 1980-02-02
AU4867379A (en) 1980-01-24
BE877666A (en) 1979-11-05
DE2927884A1 (en) 1980-01-31

Similar Documents

Publication Publication Date Title
US2986455A (en) Bonded abrasive articles
CA1129269A (en) Structural material for acoustic machines and instruments
US4022302A (en) Disc brake pads
WO1998048948A1 (en) Porous metal/organic polymeric composites
AU580720B2 (en) Method of preparing wood-fibre boards
US4026384A (en) Reconstituted mica acoustic diaphragm
US3923309A (en) Cartridge shell for phonograph pickup
USRE31589E (en) Thermal insulation molten metal
JPH08297492A (en) Damping sound insulating material
CN213382363U (en) Gas-powder separation device of full-automatic plastic-powder dust-free stirrer
JPS61275175A (en) Inorganic hardened body composition
US2826505A (en) Porous media
JPS5916280B2 (en) composite material
US2314340A (en) Coating granular materials and product thereof
JPH01896A (en) Diaphragm for speaker
GB2106300A (en) Construction of record playing apparatus
JPH027324Y2 (en)
SU1114943A1 (en) Ultrasonic converter and method producing thereof
JP2551268Y2 (en) Formwork
JPH071910Y2 (en) Speaker-cabinet
JPS6315025Y2 (en)
JPH04357003A (en) Manufacture of porous pzt ceramics
JPS5538739A (en) Acoustic diaphragm
JPS589499A (en) Speaker cone
JPS5853558B2 (en) Diaphragm for speaker

Legal Events

Date Code Title Description
PCNP Patent ceased through non-payment of renewal fee