Laminated article with acoustically active layer
FIELD: building units, particularly laminated articles of vegetable material providing high acoustic properties and adapted to be used in rooms, electromechanical audio transmitters, musical instruments and the same objects.
SUBSTANCE: laminated article comprises outer layer made of wooden material, namely of wood veneer, and inner layer comprising dried plant stems and made as chips or bars of dried burdock stems. The inner layer is active acoustic layer. The article has modulus of elasticity in static flexure of 2.63×1010N/m2, density of 190-215 kg/m3 and ratio between modulus of elasticity and density of (138.4 - 122.3)×106 m2/s2.
EFFECT: extended range of technical means for article production.
The invention relates to layered products of vegetable matter, in particular to the products, providing high acoustic properties 1) premises, especially recording and voice-over studios, concert halls, sound studios with high-quality acoustic electroacoustic equipment, 2) Electromechanical transducers of sound (speakers etc), 3) musical instruments and similar objects. The invention can be used in construction, in the manufacture of musical instruments, buildings and furniture for audio and recording equipment.
Known layered product described in U.S. patent No. 4207964, class E 04 1/99, publ. 17.06.1980 and represents a sound absorbing and distributing the sound element, the acoustic screen and decorative sound-absorbing panel. These products are used to improve the acoustic properties of the room and contain a layer of absorbent material, such as fiberglass, mineral wool or sponge, evenly distributed between the layers, which are, for example, panels of plywood or light metal, such as aluminum, as well as plaster or cement slab. The disadvantage of these products is harmful to the health of the sound-absorbing material, which is not environmentally Chi is tym in their production. Acoustic screen and decorative sound-absorbing panel should be large enough to produce the necessary sound absorption. Therefore, they are bulky and spoil the design space.
Known layered product described in U.S. patent No. 5975238, class E 04 1/82, published. 02.11.1999 and which is flat resonator for sound damping in the small room size. The product contains a thin (0.5-2 mm) front plate of metal (steel or aluminum), the back panel of oncocytoma elastomer commonly used for vibration isolation of machines and buildings, such as polyurethan or polyethylene. The connection between the front plate and the rear plate so that the vibration of the front plate, caused by the sound in the room is sent to the rear panel. This connection and the connection of the whole layered product with a wall of a building is provided, for example, double-sided adhesive tape. This invention eliminated the disadvantages of the previous solution: there is no synthetic fiber. However, due to the presence of steel and aluminum products are relatively expensive and has a fairly heavy weight.
Known layered product (copyright certificate №284587, CL 10 G C 3/06, publ. 14.10.1970) in the form of the soundboard, used in the manufacture of pianos and piano. The inner layer product which consists of wooden slats, installed with a gap and fixed to future piano. The surface layer of the rails on one or both sides with sealed it with a layer of sheet material, forming a continuous resonant surface. The sheet material may be a synthetic material, paper, fabric, impregnated with a special compound. This layered product in the form of the soundboard amplifies the sound of the piano or piano. The number of rails, their configuration, the size of the gaps between the rails and the characteristics of the layer of sheet metal in the product determine the timbre of a musical instrument. The disadvantage is the narrow scope.
Known layered product (copyright certificate №495698, CL G 10 D 3/02, publ. 15.12.75) in the form of a resonator for stringed musical instruments. The product is made in the form of a multilayer sheet, the layers of which are made of wood veneer and glued. The disadvantage of the product is limited acoustic properties.
It is known that to obtain good acoustic characteristics in a wide range of audible frequencies, it is desirable that the ratio of the modulus of the product to the density was as high as possible. Thus, in the description of U.S. patent No. 4337682, CL 10 G C 3/06, publ. 06.07.1982 in which it comes to the soundboard of the piano, it is proposed to increase the value of the ratio of elastic modulus to tight the tee due to the combination of steel as the inner layer and the wood or plastic for the outer layer. However, as practice has shown (patent RF №2185283, CL 27 To 3/15, 27 To 3/34, 27 M 3/16, publ. 20.07.2002, page 2), piano, manufactured under U.S. patent No. 4337682 did not have high acoustic performance in a wide range of audible frequencies and did not have the richness of sound of classical piano. In addition, the mechanical and physical properties of wood used for U.S. patent No. 4337682 for the outer layer exposed to climatic conditions, especially at high humidity. The tool is based on wood can undergo irreversible change in the environment, for example, there is a widespread cracking.
Known layered product in the form of enclosures loudspeakers or other electro-mechanical transducers of sound. For example, the well-known case speakers, made of layers of plywood glued together (patent RF №2124818, CL H 04 R 1/28, publ. 10.01.1999). This case has a low acoustic characteristics due to the strong vibration of the layers under the action of sound waves. The sound, in addition, many reflected from the walls of the shell, distorting the sound and reducing the quality of the reproduced music and sound.
To improve the acoustic properties of buildings loudspeakers and similar devices the walls of their buildings may include an absorbent layer such as a layer of fiberglass, mi is analnogo fiber, felt, powder-like material that fills the space inside the walls of the casing (U.S. patent No. 4869340, CL H 05 K 5/00, publ. 26.09.1989), zamenopoulos mixture, for example, a mixture of gipsoteca and shale (U.S. patent No. 4445730, class. And 47 In 81/06, publ. 30.07.1981). However, these layers do not resolve to the desired extent, the problem of absorption of sound, and therefore do not improve the acoustic properties of buildings. Use as a layer of powdery material (sand, graphite, silica), filling capacity within the casing, and cement mixtures weight to the product and is not technological.
In U.S. patent No. 4678715, CL 32 In 21/04, 32 21/06, B 05 D 1/18, B 05 D 3/02, publ. 07.07.1987 described technical solution relating to a resonant products, such as musical instruments, body acoustic equipment or wall cladding in the form of panels concert halls, etc. These products can be made according to the above patent plates of wood, which was consistently akoumianakis, then processed pairs of monomer to saturate them with the surface layer of the wood, re-akoumianakis, were subjected to excessive pressure of the inert gas at an elevated temperature (140°-200°). As a result, the surface of the wood (on the walls of the pores and capillaries) was formed polymer layer monomial is RA. The modulus of elasticity was 1,36-1,38, N/m2(PA)density of 480 kg/m3the ratio of elastic modulus to density - (28,3-28,7)×106m2/s2.
In the patent of Russian Federation №2185283, CL 27 To 3/15, 27 To 3/34, 27 M 3/16, publ. 20.07.2002, for the invention "Method of processing wood for musical instruments" describes the top layer of wood formed by the polymerization of: a layer of native wood fibres, bonded together by a carbon material obtained by polymerization of acetylene or other hydrocarbon ratio s/N close to unity) in glow discharge plasma.
The disadvantage of the layered product according to the above U.S. patent No. 4678715 and the Russian Federation No. 2185283 is that their manufacture requires considerable expenditure of energy, the technology is complex and the use of environmentally hazardous substances. In addition, their production should be a tree whose availability is currently declining due to environmental problems.
For the closest analogue (prototype) of the selected technical solution described in U.S. patent No. 4364990, CL 32 In 7/02, publ. 21.12.1982. This patent proposes the soundboard stringed musical instruments to perform in the form of a layered product in which the increase of elastic modulus to density is achieved by performing vneshnej the layer of fibers, in particular, graphite fibers with a modulus of elasticity of 1.8×1011(PA) density not less than 2000 kg/m3and accordingly the ratio of elastic modulus to density 90×106m2/s2. Fiber embedded in a matrix of polymeric material. As the inner layer using a material with a density lying in the range 150 kg/m3and 1000 kg/m3preferably cardboard or heavy paper. The disadvantage of these decks is that they are expensive and do not have a sufficiently high acoustic performance in a wide range of audible frequencies, characteristic of classic high-quality musical instruments. And the production of cardboard or paper is environmentally harmful and requires as raw material of the same wood.
Objective of the claimed invention is an expanding Arsenal of layered products that are intended for different objects, which have to meet specific acoustic requirements, for example, for indoor recording studios, for enclosures loudspeakers, musical instruments. At the same time declared layered product has a high acoustic properties based on the organic matter of vegetable origin, receipt of which is simple and low-cost technology. The latter, in particular, due to available the ability and easy reproducibility of raw materials.
The technical result is to achieve the layered product of the above purposes.
As the closest analogue (prototype), the claimed product is layered, that is, contains layers.
Unlike the prototype declared layered product includes a layer containing vegetable matter on the basis of the dry stems of burdock (Arctium).
In the layer containing vegetable matter on the basis of the dry stems of burdock, burdock stalk can be ground to a flour.
The drawing shows an example of a specific implementation of the declared layered products with the following symbols: 1 - layer containing vegetable matter on the basis of the dry stems of burdock (Arctium), 2 - another layer. In this particular accomplishment of stated layered product may include layer 1 containing vegetable matter on the basis of the dry stems of burdock (Arctium). Layer 1 may be the inner layer, surrounded by the other 2 layers. Other layer 2 may be made of wood, plastic veneer, or any other solid (sheet) material, serving, for example, as a wall of the casing of the musical instrument or the speaker, as the walls of the building. The choice of material of the other layer 2 may depend on where you use a layered product.
Layer 1 containing vegetable matter on the basis of the dry stalk burdock is (Arctium), can be manufactured as follows. The dry stems of burdock split, for example, on a long narrow strip of arbitrary shape. The chips pressed with a binder in the form of a single layer. Or stems of burdock carefully cut into rectangular strips and glue the side surfaces of the rails to each other before the formation of a continuous layer.
In layer 1, the dry stalk of burdock can be crushed to the powder. The stems of burdock, crushed to the powder, mix with the binder. The mixture gives the desired shape under pressure. If another layer 2 is, for example, veneer or similar sheet material, and the dry stems of burdock crushed state chips or flour, then another layer 2 link layer 1 containing vegetable matter on the basis of the dry stems of burdock, simultaneously with the pressing. However, their bonding occurs through the binder, speaking at the surface of the layer 1 in the pressing of the layer 1. The connection layers 1 and 2 can be performed after the molding or after the formed layer of the rails on the basis of dry stems of burdock. Binder (adhesive) can be, for example, adhesive stamps PVA.
Other layer 2 can be formed of a polymeric film formed from the dried binder (adhesive), speaking at the surface of isdel what I'm after pressing, flour or chips or specially imposed from above.
For said layered product, in which layer 1 is made of internal and containing chips or Reiki from the dry stems of burdock, and the other outer layer 2 is wood veneer, the modulus of elasticity in static bending for said layered product is 2,63×1010N/m2the density depending on the performance of the product is within 190-215, kg/m3the ratio of elastic modulus to density, respectively (138,4-122,3)×106m2/s2. Thus, the ratio of elastic modulus to density, indicating a good acoustic characteristics in a wide frequency range, has a high value.
In mild shock to the claimed product, it sounds no less clear than when the same attack on the wood of the musical instrument.
When placing speakers the speaker enclosure as claimed layered products, increases the volume of the speaker on a separate frequency range from 200 Hz to 10,000 Hz in comparison with the prototype.
Tested speakers with dynamic heads of speaker brands HDS-7, HDS-5-4, DS-X-4, in which a rectangular resonant case was made as stated layered product with an outer layer of wood veneer. If this were filmed graphics according to what astate and volume which in appearance was similar to the graphs presented in U.S. patent No. 4364990 for the prototype and for the resonant spruce. This indicates a good acoustic properties declared layered products. The speaker cabinets provide a low characteristic harmonic coefficients, which also indicates their good acoustic properties. Thus, column-based head DS-X-4 has the following characteristic harmonic coefficients: 0,81% at 250 Hz and 0.22% at 1000 Hz, 1,76% at 2000 Hz and 0.48 per cent at 6300 Hz. For the columns based on the heads GDS-7-1 and GDS-5-4 characteristic harmonic coefficients are slightly higher, but also testify to the good acoustic properties of their resonant enclosures. So, for the column with dynamic head GDS-7-1 characteristic harmonic coefficients was 8,32% at 250 Hz, 7,28% at 1000 Hz, 1,32% at 2000 Hz and 0.57% at 6300 Hz. For columns with dynamic head GDS-5-4 characteristic harmonic coefficients was 5,62% at 250 Hz, 0.16 per cent at 1000 Hz, 0,74% at 2000 Hz and 0.63% at 6300 Hz. In addition, in columns with dynamic heads HD-X-4 and GDS-5-4 no coloration of the sound at the frequency of 250 Hz, about which there is the greatest range of movement of the cone and the volume in these columns. For columns with dynamic head GDS-7-1 this coloration of the sound at a frequency of about 250Hz was only 21.5 per cent.
Moist stated the product after drying in air at a temperature of 50°not deformed and does not change the geometric dimensions.
Declared layered product may be substituted for the purposes of achieving good acoustic characteristics of wood products whose availability in some areas currently is reduced because of the reduction of the area of forests. Burdock is a malicious weed growing everywhere, as well as renewable raw materials, the cost of cultivation and processing for use in the claimed layered product are very low.
Layered product with acoustic properties that include the outer layer, made of wood material, and the inner layer containing the dry stems of plants as active acoustic layer, characterized in that the quality of wood material used wood veneer, as the dry stalks of the plants used chips or Reiki from the dry stems of burdock, when this layered product is characterized by a modulus of elasticity in static bending 2,63·1010N/m2density 190-215 kg/m3, the ratio of elastic modulus to density, respectively (138,4-122,3)·106m2/s2.
FIELD: hydro-acoustics, namely, engineering of means for hydro-acoustic protection of structures operated in water environment.
SUBSTANCE: hydro-acoustic protection device consists of metallic base and pressed rubber plates mounted on its outside forming hydro-acoustic cover, made of external solid layer and co-vulcanized to it and positioned below aforementioned solid layer and metallic base of peripheral layer with air hollows in form of cones, cross-section of which expands towards aforementioned metallic base and which are hermetically sealed on one side by aforementioned solid layer, and on other side - by metallic base. Plates of hydro-acoustic cover are made of rubber mixtures on basis of butadiene-nitrile rubbers with paraffin emulsifier.
EFFECT: improved ecological safety of environment, during production of hydro-acoustic protection devices without replacement of available expensive technological accessories and equipment, used during manufacture of devices and during mounting, with maximal possible degree of preservation of whole complex of their technological, acoustic and operation properties.
FIELD: mechanical engineering, in particular, devices, decreasing vibro-acoustic activity of supporting elements, for example, shafts, rotors, bearing units.
SUBSTANCE: resiliently damping support contains body, bearing unit with shaft in bushing, and resilient element, positioned between bushing and body, resilient element is made in form of at least two resiliently held blocks, positioned in a gap between body and bushing of bearing unit, each on of which blocks consists if two resilient bushings, made of polyurethane for example, positioned on both sides of profiled aperture of body, and holding element, made in form of resilient rod, passing through bushings, profiled aperture in the body and apertures in bushing of bearing unit.
EFFECT: increased efficiency of vibro-isolation.
FIELD: mechanical engineering, in particular, engineering of devices for lowering vibro-acoustic activity of supporting elements such as shafts, rotors, bearing units.
SUBSTANCE: resiliently damping support contains body, bearing unit with shaft in a bushing, and resilient element positioned between bushing and body, resilient element being made in form of at least two resiliently held blocks, positioned in a gap between body and bushing of bearing unit, each one of which blocks consists of resilient bushing made of polyurethane for example, and holding element, made in form of four-leaf bushing, inserted into resilient bushing and held by spreader rod. Resiliently holding block is positioned by one section in aperture of body, and by another section - in the gap between two leaves made in bushing of bearing unit.
EFFECT: increased vibro-isolation efficiency.
FIELD: methods for transferring messages in systems with check connection and special multi-band processing of transmitted and received messages.
SUBSTANCE: in method and device, algorithm for calculation and generation of delays of components of message being transferred is improved. Invention describes variants of construction of single-channel and multi-channel communication systems, making it possible to realize broadband and multi-band methods for transferring messages of any physical origin using new algorithm for calculation and generation of phase-frequency or time-frequency characteristic of optimally pre-distorting filter.
EFFECT: increased precision of transfer of messages.
2 cl, 8 dwg
FIELD: engineering of piezo-electric transformers.
SUBSTANCE: ultrasound piezo-transformer with dry acoustic contact contains solid sound duct, having internal working side for dry acoustic contact with environment being researched. Solid sound duct consists of two parts of similar or different compositions, combined as single block, one of which, containing internal working side, is made of solid material, and another one, containing external working side, is made in form of plate of porous material, having solid matrix, with volume of pores not less than 17% of plate volume.
EFFECT: increased transfer coefficient, expanded working range of temperatures.
8 cl, 1 dwg
FIELD: mechanical engineering; transport engineering.
SUBSTANCE: according to invention, engine compartment of car accommodates both noise-and-vibration generating base members of power unit, unit and system of internal combustion engine and no-noise base members of units and systems of car. External surfaces of walls of at least part of noise-and-vibration generating and no-noise parts and/or units, and/or systems are either partially or fully lined with porous noise-absorbing members-panels, linings of covering whose external surface is protected by noise-transparent film.
EFFECT: provision of effective absorption of sound waves of diffuse sound field of car hood space, damping energy of sound waves generated by structural vibrations of walls of noise and vibration generating parts.
9 cl, 9 dwg
FIELD: technologies for emitting intensive sound waves, technology for transferring sound energy over large distances, possible use in active location equipment - long range hydro-locators, underwater communication systems, hydro-acoustic detection and control systems.
SUBSTANCE: method for suppressing nonlinear sound absorption includes, in the same direction as signal wave movement and together with wave, study of additional wave, frequency f2, phase φ2 and amplitude A2 of which is selected in accordance to following relations: f2=3f1, φ2=3φ1, A2=A1/4, where f1 - frequency, φ1 - phase, A1 - signal wave amplitude.
EFFECT: increased manufacturability of method for suppressing nonlinear sound absorption.
FIELD: automotive industry.
SUBSTANCE: invention relates to multilayer noise-isolating structures designed for improving acoustic and climatic conditions and riding comfort in passenger compartment (cab) of vehicle, for instance, automobile. Proposed integral noise-isolating structure of cab and/or passenger compartment of vehicle has solid-formed skeleton made of tight weight-carrying layer of gastight material, at least part of mounting surface of which is mated with layer of porous foamed material permeable to gas, and face surface of weight layer is mated with layer of decorative carpet coating. Structure of porous layer is of homogeneous chemical composition with different value of rigidity within the limits of mounting surface mated with panel of body. Separate more rigid sections of structure of porous layer are formed by isolated groups of close-meshed formations within the limits of thickness of porous layer at place of formation and separate more soft sections of structure are formed by isolated groups of wide-meshed formations within the limits of entire thickness of porous layer in place of said formations, moreover said isolated groups of close - and wide-meshed formations are arranged on surface of structure in alternating manner, according to proposed version.
EFFECT: reduced weight of vehicle and simplified mounting of structure in confined space of cab and/or vehicle passenger compartment, preservation of high acoustic properties of integral noise-isolating structure in process of storing, transporting and long operation on vehicle.
7 cl, 20 dwg
FIELD: noise-absorbing panels.
SUBSTANCE: multilayer noise-absorbing panel has a layer of porous, gas-penetrable, open-cell foam noise-absorbing material, which is protected by thin layer of sound-transparent gas-impenetrable film-like material. Structure of porous layer of sound-absorbing material, for given space direction of structure volume, is formed by a set of directionally grouped in a certain way, at least two types of families of alternating pores of different geometric dimensions, forming an appropriate specifically given non-homogenous rigid skeleton frame structure. Groups of families of lesser pore groups form volumetric zones of structure with higher rigidity in comparison with volumetric, softer zones of structure, formed by families of larger pore groups of porous layer. Face surface of porous sound-absorbing material layer is in thermal-adhesive and gapless way is connected to thin protective layer of gas-impenetrable sound-transparent film-like material with forming of resulting, having appropriate non-homogeneousness of rigidity, density, resistance to blowing-through sound-absorbing structure in form of alternating volumetric zones and local surface projections and recesses of waving-wrinkled shape.
EFFECT: higher efficiency, broader functional capabilities.
FIELD: nondestructive ultrasonic methods of inspection.
SUBSTANCE: in the offered ultrasonic objective, having a body, with a piezoelectric transducer located on one of its end faces, and a tapered concentrator on the opposite end face, having an acoustic contact with the test piece through immersion oil and positioned coaxially with the piezoelectric transducer, the body is made electroconducting. The body includes coaxially positioned outer and inner conductors provided between which is a dielectric filling. The tapered concentrator base is located on one of the end faces of the body by means of the first conduction layer connecting the concentrator to the outer electrode. The piezoelectric transducer is positioned in the center of the concentrator base and connected to the central conductor of the coaxial line by means of the second conduction layer.
EFFECT: improved electric matching at high operating frequencies at conservation of a high resolution and efficiency of electroacoustic transformation.
FIELD: aircraft construction, building industry and mechanical engineering.
SUBSTANCE: panel comprises sheeting and filler of corrugated sheet material. Corrugation walls extend at an angle to horizontal plane, in which projections and valleys alternate in zigzag order.
EFFECT: reduced noise due to sound wave dissipation.
FIELD: building units, particularly for heat insulation.
SUBSTANCE: article comprises layer of heat-insulation material and mineral fiber material having opposite sides, two major surfaces and thickness defined by above surfaces. Article includes fastening means to provide article fixation. Fastening means extends from the first article end in the first direction substantially parallel to one major surface. The first and the second ends of fastening means adjoin corresponding layer side. Fixing means may be increased in length to secure article to building structure so that fixing means may extend outwards from article sides. Length increase is carried out by applying pulling force to fixing means end.
EFFECT: provision of article adjustment in length and shape, possibility to connect article to itself, to adjoining sheets, to structure to be insulated and so on.
26 cl, 6 dwg, 2 ex
FIELD: manufacturing of nonwoven fabrics.
SUBSTANCE: reinforcing nonwoven fabric comprises two groups of fibers arranged at a right angle one to the other in the longitudinal and transverse direction of fibers. The fivers are locked by means of a binder. The both of the groups of fibers define a three-layered structure so that the group of transverse fibers is interposed between the top and bottom groups of the longitudinal fibers. The fibers of each group are made of glass roving with the linear density no less than 400 text. The method of making reinforcing nonwoven grid is proposed.
EFFECT: enhanced strength.
5 cl, 1 tbl, 4 ex