Helical-type sound absorbing element

FIELD: electronic engineering.

SUBSTANCE: invention relates to a helical-type sound absorbing element. Helical-type sound absorbing element comprising a smooth and perforated surface, between which there is a layer of sound-absorbing material of complex shape. Layer of complex shape is an alternation of solid sections and hollow sections. Hollow sections are formed by prismatic surfaces with cross-sections parallel to plane of drawing, parallelogram shape, which inner surface have toothed or wavy structure. Teeth tops face inside prismatic surfaces. Ribs of prismatic surfaces are secured on smooth and perforated walls respectfully. Cavities of hollow sections formed by prismatic surfaces are filled with a sound absorber. Between a smooth surface and solid sections of the layer of sound-absorbing material of complex shape, as well as between the perforated surface and solid sections, there are resonant plates with resonant inserts performing the functions of the neck of the Helmholtz resonators.

EFFECT: technical result is higher efficiency of sound proofing.

1 cl, 2 dwg



Same patents:

FIELD: construction.

SUBSTANCE: sound-absorbing element includes perforated surfaces, between which a sound-absorbing structure is arranged and consists of three layers of sound-absorbing material. The first layer, which is a stiffer one, is solid and shaped and fixed on upper perforated surface. The second layer, which is a softer one than the first layer is discontinuous and located in focus of sound reflecting surfaces of the first layer. The discontinuous sound absorbing layer located in focus of a solid shaped layer is made in the form of rotation bodies, for example in the form of balls, and attached by means of rods parallel to upper and lower perforated surfaces, which are rigidly attached to the upper perforated surface by means of vertical fasteners perpendicular to them, for example in the form of plates, one end of which is rigidly fixed on the upper perforated surface, and the other one is made in the form of a clamp enveloping the rod and tightening it by means of a screw.

EFFECT: improving noise control efficiency and reliability of the structure as a whole.

5 cl, 1 dwg

FIELD: machine building.

SUBSTANCE: invention relates to safe working facilities. An acoustic cabin comprises a base, a frame, life support equipment, window and door apertures and enclosures in the form of acoustic panels. The base is mounted on at least three pneumatic vibration isolators made as a rubber cord shell, and a cabin frame in the form of acoustic sound absorbing panels of parallelepiped shape is rigidly attached to the base, the parallelepiped is formed by the front and back walls of the panel with sound absorbing material placed in-between. Each wall is of U-shape. Slot perforation is made on the front wall and its perforation coefficient is equal to or exceeds 0.25. The front wall is glazed by sound reflecting translucent panel made as a polygon, for example, a rectangle, formed by U-shape ribs made from vibration damping material. A panel from solid plate out of extruded polycarbonate plastic is used as the sound reflecting translucent element. The frame also consists of a ceiling with luminaries, a back wall placed in the plane parallel to the front wall plane, and four side walls with a door provided in one of them. The area of the back wall is by at least 2 times greater than the area of the front wall, and side walls adjoining the front wall are inclined to it and glazed, and those adjoining the back wall are perpendicular to it. The cabin is leakproof and is equipped by a life support system in the form of an artificially maintained environment system with a control panel, for example, a cartridge conditioner produced by General Climate. Operator's workstation is equipped by a work table and a chair with vibration isolators in the form of elastomer plates attached to the chair legs. "Vibroflex EP/25A" type or "VEP" type vibration damping plates are used as the above elastomer.

EFFECT: invention allows for increased operator's work efficiency due to decreased levels of dust and noise.

9 dwg

FIELD: machine building.

SUBSTANCE: resonant acoustic absorber comprises a rigid frame consisting of an upper active part and a lower reactive part. The reactive part is made as three coaxial and axisymmetrical resonant cylinders with their cavities being fitted by holes of different diameter serving as Helmholtz resonator necks. Supporting disks set at the cylinder ends connect the latter to each other in rigid and leaktight manner forming the reactive part of the rigid frame of the acoustic absorber. The upper active part is made in the form of a rigid perforated cylindrical shell with a perforated cover and a solid base. The cavity of the cylindrical shell is filled with sound absorbing material. At least one spiral acoustic absorbing element in the form of a cylindrical coil spring enclosing the shell is mounted around the perforated cylindrical shell. The upper and lower parts are interconnected by a resilient damping element.

EFFECT: improved efficiency of noise suppression at high frequencies.

2 cl, 1 dwg

FIELD: construction.

SUBSTANCE: invention relates to the industrial acoustics and can be used to reduce the noise of the machine drives, covering of industrial premises. Device comprises the perforated surfaces, between which the sound-absorbing multilayer structure is arranged. Layers of sound-reflecting and sound-absorbing materials of different densities are disposed between the perforated walls. Layers of sound-reflecting material are made of complex profile, consisting of uniformly distributed hollow tetrahedrons, located at the perforated walls. Layers of sound-reflecting material are made of heat-insulating material, capable to support the specified microclimate in the promise. Sound-absorbing element over the entire surface is covered with acoustically transparent material. Porous material or material in the form of the compressed crumbs made of solid vibration-damping materials is used as the sound-absorbing material.

EFFECT: increases efficiency of noise suppression and reliability of the design.

3 cl, 1 dwg, 1 tbl

FIELD: machine building.

SUBSTANCE: in sound-absorbing structure containing solid and perforated surfaces a multi-layer sound-absorbing material is located between the surfaces. The sound-absorbing element is made out of three layers: central layer out of sound reflecting material with complex profile, containing uniformly distributed hollow tetrahedrons, and symmetrically abutting to it sound-absorbing layers out of the materials with different density. As the sound-absorbing material the mats out of mineral wool "Rockwool", or "URSA", or out of basalt wool P-75 are used. The sound-absorbing element is lined with acoustically transparent material.

EFFECT: enhanced efficiency of sound absorption and reliability of the structure.

5 cl, 1 dwg

FIELD: physics, acoustics.

SUBSTANCE: invention relates to means of ensuring safe operation of operators in emergency situations, particularly at high noise levels. A system for acoustic protection of an operator, comprising an operator workstation located between acoustic shields and a suspended ceiling; in the upper area of the building, to reduce sound vibration, the operator workstation is fitted with a floor with an elastic base, wherein the operator is provided with two-stage vibration protection.

EFFECT: high efficiency of soundproofing.

2 tbl, 7 dwg

FIELD: machine building.

SUBSTANCE: sound absorber of combined type contains sound absorbers of active and reactive types located on rigid framework, framework is out of two parts, at that bottom part, i.e. reactive part, is made as rigid hollow cylinder, its bottom is connected with a support disk connecting it with a support disk on which via the resilient dampening element a top part of the framework is installed, it is made as rigid perforated cylindrical shell with perforated cover and solid base connected with the support disk, the cylindrical shell cavity is filled with sound-absorbing material, and the top and the bottom parts are connected by means of the resilient dampening element ensuring dampening of HF oscillations; at that to the perforate cover of the cylindrical shell the element is hingedly connected, using this element the framework is secured to the required object, for example, ceiling of the production room, and around the rigid perforated cylindrical shell at least one helical sound-absorbing element is installed made as cylindrical screw spring enclosing it and resting against the support disk; at that the cylinder cavity of the framework reactive part is tightly covered by the support disk with at least one hole functioning as mouth of Helmholtz resonator, that is crated together with the cylinder cavity, and around the hollow cylinder at least one helical sound-absorbing element is installed, that is made as cylindrical screw spring enclosing the hollow cylinder and resting against the support disks.

EFFECT: improved efficiency of noise suppression at high frequencies.

2 cl, 1 dwg

FIELD: transport.

SUBSTANCE: invention relates to industrial safety. Proposed cabin comprises the bed, carcass, life-supporting hardware, window and door openings and guards composed of acoustic panels. Said bed is installed at, at least, three pneumatic bumpers composed of rubber-cord shell whereto secured is cabin carcass composed by acoustic noise-absorbing panels shaped to parallelepiped composed by front and rear panel walls with noise absorber arranged there between. Every wall features U-like shape. Front wall has perforation. Front wall has glazing composed of noise-reflecting translucent polygonal panel. Said noise-reflecting translucent polygonal panel is composed by solid extruded polycarbonate plastic. Ceiling section is provided with illuminators. rear wall is located in the plane parallel with front wall plane. Side walls abutting on front wall are inclined thereto and glazed while those abutting on rear wall are perpendicular thereto. Sealed cabin is equipped with life supporting system composed by artificial microclimate system with control board. Noise absorber is composed of stiff and perforated walls with sound reflecting plies and sound absorbing materials plies arranged in two plies. Note here that sound-reflecting plies feature complex profile composed of uniformly distributed hollow tetrahedrons to allow reflection of sound waves falling in all directions which are arranged nearby stiff and perforated walls. Said plies are made of heat-insulating material to sustain preset micro climate in a room. Boards of mineral wool or glass wool with glass felt are used as noise absorbing material. Sound-translucent material is sued to line said sound absorbing material over its entire surface.

EFFECT: higher efficiency of operator's work.

8 dwg

FIELD: physics, acoustics.

SUBSTANCE: invention relates to means of protecting industrial areas from negative acoustic-noise action. The resonance noise absorber comprises interconnected panel with working holes in which removable elements are inserted, and a box. The removable elements have holes which act as orifices, the diameter of which, as well as the length of said elements, the distance between the centres of the orifices and between the back inner wall of the box and the end of the removable element are selected to ensure the required range of absorbed frequencies. Stiffening ribs can be used to increase rigidness of the device. The removable elements are installed to ensure tight contact between the elements and the panel.

EFFECT: creating conditions for more effective protection from acoustic-noise contamination of open technospheric areas while reducing the cost of each separate device.

6 cl, 7 dwg

FIELD: physics, acoustics.

SUBSTANCE: invention relates to industrial acoustics. Acoustic structure comprises shop carcass, load-bearing walls with guards composed of the floor and walls lined with sound absorbing structures, window and door frames and single sound dampers. Single sound dampers are composed of noise killers consisting of the case with flap cover and filled with sound absorbing material placed in protective shell. Case walls are composed by sound absorbing structure composed by cylindrical perforated coaxial shells, inner and outer, with sound absorber arranged there between. Sound absorber is composed of at least one shaped porous sheet. Note here that sheet cross-section profile can be triangular, rectangular, trapezoidal, circle arc or sinusoidal.

EFFECT: higher efficiency of noise killing.

7 dwg

Acoustic panel // 2268966

FIELD: industrial acoustic engineering, particularly broadband sound-absorbing means used in all industries to reduce noise generated by processing equipment.

SUBSTANCE: acoustic panel comprises smooth and perforated walls and sound-absorbing material arranged between the walls. Profiled sound-absorbing material surfaces are located between smooth and perforated walls and are inclined one to another at an angle less than 180°. The profiled surfaces are composed of separate members spaced predetermined intervals one from another. The smooth wall has one continuous shaped layer of sound-absorbing material.

EFFECT: increased sound-absorbing efficiency due to increased sound-absorbing surface and reduced labor inputs for panel production and source material consumption.

4 dwg

FIELD: industrial acoustics, particularly wideband sound-absorbing structures to reduce noise caused by industrial equipment operation.

SUBSTANCE: cells are formed by solids of revolution from perforated wall side. Method for cell creation involves forming sound-absorbing material by tool having shape congruent with cell shape; creating basic cell surfaces and creating additional cell surfaces. Cell forming tool is punch mating in shape with cell shape and having vertical displacement drive. The tool also has conical rod, which cooperates with inner surface formed in the punch and having the same taper angle as conical rod. Punch wall is provided with cylindrical orifices for additional shaping members receiving. The shaping members are spring-loaded relatively the wall. Compression spring is also provided. The first end of compression spring abuts annular shoulder formed in orifice. The second spring end thereof cooperates with tab washer made at additional shaping member end. The shaping member consists of two parts, namely cylindrical part and part defined by body of revolution, connected with each other.

EFFECT: increased sound-absorbing efficiency due to increased acoustical absorption factor by sound-absorbing surface increase along with structure size conservation.

3 cl, 8 dwg

FIELD: industrial acoustics, particularly broadband noise reduction of industrial equipment.

SUBSTANCE: cylindrical acoustic absorbing member comprises rigid cage suspended to industrial building ceiling by cables. The cage is filled with sound-absorbing material covered with caprone netting. The cage comprises lower and upper round perforated lids tightly connected with each other by central rod axially aligned with horizontal lid projection centers. At least three cage side forming rods are located around lid perimeters so that the cage side may have cylindrical shape.

EFFECT: increased sound absorbing efficiency due to extended frequency range and improved performance.

2 cl, 1 dwg

FIELD: industrial acoustics, particularly broadband noise reduction of industrial equipment.

SUBSTANCE: conical acoustic absorbing member comprises rigid cage suspended to industrial building ceiling by cables. The cage is filled with sound-absorbing material covered with caprone netting. The cage is made as cone and provided with semi-sphere fastened to lower cage flange. The sound-absorbing material may be placed in the case so that air cavities are formed around semi-sphere perimeter and inside the semi-sphere. The air cavities are arranged in staggered order along three perpendicular planes. Height/diameter ratio of acoustic absorbing member is H:D=2:1 ÷ 2:0.5.

EFFECT: increased sound absorbing efficiency due to extended frequency range and improved performance.

1 cl, 1 dwg

FIELD: industrial acoustic means, particularly broadband sound absorbing units adapted to decrease noise from industrial equipment.

SUBSTANCE: cylindrical acoustic absorbing unit comprises rigid case suspended to industrial building ceiling by means of hooks and cables. Acoustic absorbing material covered with netted capron tissue is placed in the case. The case has cylindrical shape and made as perforated cup with perforated lid. The case is provided with fixed central rod extending along case axis. Round partitions are connected to the rod so that the partitions may be retained in place. The partitions define cavities filled with acoustic absorbing material covered with netted capron tissue. Acoustic absorbing material has any three-dimensional shape, for instance, spherical shape.

EFFECT: increased efficiency.

1 cl

FIELD: venting systems, particularly noise-reduction of industrial ventilation and conditioning systems.

SUBSTANCE: air duct includes a number of box-like sections connected with each other by locking devices. The sections are made of light-weight sound-absorbing structures having perforated linings and facings filled with sound-absorbing filler. The filler is made of sound-absorbing materials. Facings and linings have perforation factor of not less than 0.25. Sound-absorbing filler thickness is within optimal range, namely within 20-50 mm. Covering is made of stainless steel or galvanized sheet with 0.7 mm thickness and has polymeric protective-and-decorative coating having thickness depending on coating type. Covering may be also made of aluminum sheet of 1.0 mm thickness and may be covered with 25 μm coating.

EFFECT: decreased aerodynamic and structural noise, simplified assembling and disassembling and increased comfort in rooms.

FIELD: construction, superstructures.

SUBSTANCE: principle applies to production acoustics, in particular wideband silencing, and can be used in all sectors of national economy in silencing production machinery using the method of noise absorption. The technical result is to ensure the effectiveness of noise absorption on account of increasing the frequency diapason and improving operational characteristics. Resonant acoustic absorber consists of firm frame, suspended on the ceiling of the production building, and has a sound absorbing material in the frame. The frame is made in the form of a bowl. The side surface of the bowl, the bottom and lid, to which the fastening element, that fasten the facility to the ceiling of the production building, is connected, is in the form of a perforated cable segment. In the frame, there's a central rod, firmly connected onto the bowl's bottom axis, on which on the full height of the central rod, at least, one internal partition is fixed. This internal partition forms with another or the other partitions, roof or bottom of the resonant cavity bowl. At least, in one of the partitions, there's a sound absorbing material, wrapped in acoustic transparent material. Perforation is done by slotting. The perforation coefficient of the side surface, bottom, frame lid and also the internal partition is the same and equal or greater than 0.3. The side surface of the perforated bowl in the section perpendicular to the bowl axis, has circular, elliptic, triangular or polygonal form.

EFFECT: increasing the silencing effectiveness.

2 cl, 1 dwg

FIELD: construction.

SUBSTANCE: single-piece sound absorber consists of a rigid frame suspended to the ceiling of an industrial building, with sound-absorbing material inside the frame, wrapped in an acoustically transparent material. The frame is designed as a cup with perforated lateral surface and a perforated bottom; a perforated cover is attached to the top part of the cup; a fastener in the form of a cable piece is attached to the cover, for fastening the cup to the industrial building ceiling. Inside of the frame, a central rod if fixed rigidly in the cup bottom along the cup axis; on the rod, at least one internal partition is installed so that it can be latched at a certain central rod height; forming resonant cavities with the other partition(s), the cup cover, and the cup bottom; sound-absorbing material wrapped in acoustically transparent material is located in at least one of the cavities. The perforation is slotted, the lateral surface, the bottom, and the frame cover have the same perforation ratios equal to or more than 0.3, and the internal partition has a perforation ratio less than or equal to the perforation ratio of the lateral surface, the bottom, and the frame cover; the lateral surface of the perforated cup has a rectangular or square shape in the section perpendicular to the cup axis. The frame is made of stainless steel or galvanised sheet with a thickness of 0.7 mm, with polymeric protective and ornamental coating with a thickness of 50 mcm or 25 mcm, or of aluminium sheet with a thickness of 1.0 mm and a coating thickness of 25 mcm.

EFFECT: increase in sound absorbing efficiency and performance enhancement.

4 cl, 1 dwg

FIELD: construction.

SUBSTANCE: cubic custom-made acoustic absorber consists of rigid frame that is suspended to production building ceiling with sound absorbing material that is wrapped in cloth and installed inside the frame. Frame is shaped as two cubic surfaces, one of which - external one - is made as perforated, and the other - internal one - as acoustically transparent. Sound absorbing material, which is wrapped with meshy capron fabric, is installed in the gap between the frames, which are connected between each other by means of resonance inserts of different diameter, and internal cavity is separated by partition into two resonance cavities, one of which is filled with acoustic absorber, at that lamps with power supply are installed in resonance inserts.

EFFECT: increase of sound-suppression efficiency and improvement of performance properties.

1 dwg

FIELD: construction; physics.

SUBSTANCE: acoustic baffle contains framework with metal-plated slopes and acoustic panel sections. Sections contain acoustic panels implemented as both noise-reflecting translucent panels and non-translucent noise-absorbing panels. Layout of panels in acoustic baffle may vary in any combination of vertical and horizontal lines. Baffle contains metal-plated slopes, translucent noise-reflecting panels. Framework of acoustic noise-absorbing panel is in the shape of parallelepiped formed by front and rear perforated walls with perforation factor equal to or more than 0.25. Each -shaped wall has side edges. Perforation is represented as slotted perforation aligned as lines of rectangles. Adjoining lines are shifted. There is even number of slots in one line and odd number of slots in the other. Odd lines width b1 ratio to even line width b2 is in the optimal interval of values b1: b2 = 0.7-0.9, ratio of distance between lines h1 and h2 is h1: h2 = 2.0.

EFFECT: effective noise absorption due to increase of acoustic reduction factor by increasing noise-absorbing surfaces while keeping baffle dimensions.

3 cl, 6 dwg