EP1340221A1

EP1340221A1 - Layered material

Info

Publication number: EP1340221A1
Application number: EP00993916A
Authority: EP
Inventors: Thomas Wiegel
Original assignee: Individual
Current assignee: Individual
Priority date: 2000-11-21
Filing date: 2000-11-21
Publication date: 2003-09-03
Anticipated expiration: 2020-11-21
Also published as: EP1340221B1; DE50015321D1; AU2001228261A1; ATE405917T1; WO2002043047A1

Abstract

The invention relates to a layered material for influencing the vibrational, radiational and/or tonal behaviour of particularly flat sound-radiating elements. Said layered material comprises at least two layers which are disposed on top of each other and joined together, each layer consisting of parallel or angularly disposed bar-shaped support elements (1, 2) whose initial and the end points are joined to other support elements or installed in a sound-radiating element and connected thereto.

Description

Layer material

The present invention relates to a layered material for influencing the vibration, radiation and / or sound behavior of, in particular, flat sound-radiating elements.

Disturbing and damaging noises are the main stress factors in our acoustic environment. They arise when functional parts move in a structure that excite the structure itself and / or coupled light, flat parts to vibrate. The intensity and sound quality of this sound radiation are determined by functional requirements, in particular stability and weight, and are usually such that corrective measures are necessary.

A large number of measures for influencing (damping) the vibration, radiation and / or sound behavior of flat sound-emitting elements (components, molded parts, etc.) are known from the prior art. These include anti-drumming materials (increase in mass and friction), sandwich constructions (use of different material properties), spacers, changes in stiffness, resonance damping, reduction in vibration initiation, transfer to less radiant parts of the Construction, active measures with phase shifted movements etc.

However, the measures listed above are sometimes very complex and in particular inadequate if, on the one hand, stability and weight requirements have to be met, on the other hand there is a technical and economic wish / constraint to reduce sound radiation and vibration by a reasonable amount, to make them more pleasant or in addition to actively influence.

The invention has for its object to provide a layer material of the type specified, which, with a simple structure, a low weight and a simple installation option, has a particularly effective influence, in particular damping, of the vibration, radiation and / or sound behavior of in particular flat sound-emitting elements.

This object is achieved according to the invention in the case of a layer material of the type specified in that it comprises at least two layers arranged and connected to one another, each consisting of rod-shaped carrier elements spaced parallel or at an angle to one another, the starting and end points of which are with other carrier elements or in the most radiant manner Element installed state are connected to this and form the nodes with support elements arranged at an angle to the same layer and / or an adjacent layer.

The rod-shaped support or structural elements of the layers are the easiest way to achieve the slow wave speeds required for influencing / damping (especially low frequencies), since rods are not only slower (longitudinal) wave have speeds as flat elements, but the slowest at all, on the other hand, such rods enable particularly stiff and light structures.

Since each individual support or structural element can be defined in terms of material, dimensions and position in relation to the flat sound-emitting element, the basic acoustic elements of mass, spring, friction, stiffness can be freely assigned (ie largely independently of one another) to each individual surface element, and its amplitude , Frequency and phase can be designed within particularly wide limits. Due to the improved availability of energy (based on the same weight), the known optimization limits of damping are overcome. Due to the design of frequency and phase behavior as well as the controlled generation of near fields, psychoacoustic phenomena can also be used in the product area.

The layer material is completely modular due to the free definability of its structural elements and can therefore be adjusted to a wide variety of acoustic framework conditions (area size, excitation intensity, excitation spectra, excitation locations, area modes, area shape, boundary conditions). A wide variety of tasks can also be performed, for example Optima for all operating conditions, desired sound properties, minimal airborne sound radiation, minimal deflection, etc.

Due to the simple integration of active elements, this optimization can react even better to random influences from the environment or produce more differentiated results.

Each layer having the rod-shaped support elements (Support grid or support row / support coulter) must ensure a transfer function from the surface of the flat sound-radiating element on which the layer material is arranged to the layer material and an exchange function of the support layers with one another and be dimensioned so that the grid resolution (distance of corresponding nodes or . Contact points) of the acoustic task, which means, for example in the case of damping, that the spacing of the contact / grid points must be small compared to the wavelength of the wave type to be damped, and a material with such low wave speed is selected that several phase states of the lower limit frequency find space in the area. Furthermore, the grid (the structure) must withstand damage, such as temperature, shock or force effects (centrifugal forces, accelerations). This is achieved through appropriate shaping, structuring, dimensioning and material selection and, if necessary, through additional stabilizing or protective elements.

In order to influence the vibration, radiation and / or sound behavior of a planar sound-radiating element, the layer material designed according to the invention is connected (attached) to the corresponding surface of the sound-radiating element, for example glued to it. The surface, the oscillation, radiation and / or sound behavior of which is to be changed, can be flat, spherical or of any shape. In addition, cylindrical and conical bodies, spheres, torus rings and all bodies and structures with thin-walled, light boundary surfaces are possible.

Vibrations of the flat element (bending shafts) are in principle fully absorbed on the layer material attached to it. areal transfer. Several coherent waves are excited in the material, at least two parallel to the surface. There can also be one wave perpendicular to the surface and two more parallel to the surface and Raleigh-like waves. The energy exchange of the waves takes place via the contact points / nodes.

The known conditions for coherent waves are given. A temporal and / or spatial statistical wave pattern is created in the material, because any number of points on the surface of the sound-emitting element are assigned in a phase-locked manner to any number of points in the material, and from one point on the surface of the sound-emitting element there are several phase-defined paths ^' to any point of the material , Since the phase, location and direction of the waves can be controlled, wave extinctions occur, whereby the mechanical energy is converted into heat (the large surface area of the material ensures good heat dissipation to the environment).

The carrier elements used in the layers according to the invention in principle enable very light, stable structures and / or have the lowest possible longitudinal wave speeds. They have a large, non-radiant surface and almost unlimited combination options.

The layer material designed according to the invention is in principle modular. This means that each individual or grouped support element (or a part thereof) and each group of support element groups can be assigned a special position, dimension, shape and material. In addition to this modular assignment, the carrier elements and also the associated planar sound-radiating element itself can have the basic acoustic elements of mass, rigidity. speed, friction and spring can be assigned to a determinable degree and within the scope of the available resources or specifications in accordance with the acoustic goals.

The flat sound-emitting element, the oscillation, radiation and / or sound behavior of which is to be changed, can be flat, spherical or arbitrarily curved.

In use, the layer material designed according to the invention is coupled to the flat sound-radiating element. The layer material transforms the excited bending waves into other types of waves, for example into quasi-longitudinal waves, i.e. wave fronts directed transversely to the direction of radiation. This means a transition from a one-dimensional concept of the sound-emitting surface to a surface with space close to the surface and establishes a spatial and wave-based (multi-dimensional) concept / treatment of the surface itself.

The movement of the flat sound-emitting element (flexible shaft) is controlled by a lever / deflection function (transmission of torques or shear forces) and a contact / coupling point matrix in several wave fronts running parallel to the surface (perpendicular to the radiation movement) and / or in non-radiation-capable structural elements that vibrate in the same direction transferred what happens through the layer material arranged in the vicinity of the surface, which has layered, transversely oriented and phase-defined functional elements coupled in the form of layered carrier grids or crossing carrier line sets.

In order to transport the wave fronts, the functional elements must be wave-capable, ie in wave propagation direction generally, statistically or periodically homogeneous, and generate definable wavefronts in phase and direction, which can be achieved by their shape, position and material properties.

To mutually dampen / influence the wave fronts generated in the layer material, all / selected wave fronts must be able to be coupled in a phase-defined manner, which can be achieved by crossing, i.e. through coupling points (a coupling point grid) designed as contact points and / or nodes of the wavefront-carrying functional elements. At the same time, these form the phase-defined transition points between the surface and more remote structural elements and create multiple phase-defined wave excitation centers, the prerequisite for coherent waves.

The further developments of the subject matter of the invention emerge from the subclaims. The following must be carried out in detail:

The carrier elements are preferably longer than their largest cross-sectional dimension. Here, the term "length" is defined as the distance from node to node.

Two or more layers arranged one above the other can be used, which form the layer material formed according to the invention. One or more intermediate layers neutral to sound radiation can be arranged between these layers of the individual carrier elements. Furthermore, the layer material can have a sound radiation-neutral end layer.

The carrier elements of a layer are preferably in straight the or kinking carrier lines and these arranged in parallel or angular groups, so that layers of carrier element groups or carrier element grids result.

As for the shape or the cross section of an individual carrier element, this can have a square, rectangular, polygonal, circular, elliptical or irregular cross-sectional contour. The cross section can be full or hollow, be hollow layered, have a core and one or more shells and consist of different materials in cross section or a part thereof. Any combination can be used.

As far as the shape of the support elements is concerned, they can have a cross-sectional contour that is constant over their length. However, the cross section can also change, in particular for the formation of special large-area nodes. In particular, variable cross-sectional changes and also variable cross-sections can be borrowed over the length

Material compositions can be realized. Typical cross-sectional dimensions of a carrier element are 0.01 to 10 mm (diameter).

As far as the material of the carrier elements is concerned, it can be plastic, plasto-elastic or elastic. There may be gaseous, liquid, solid, bubble-shaped, drop-shaped, fibrous, thread-like, amorphous, etc. inclusions. The surface can be rough, for example, but can also be smooth.

The nodes provided according to the invention arise as an intersection of carrier elements of a layer and / or of touching layers and / or a selection / of all existing layers. Nodes arise when a Layer is formed as a grid and / or when two sets of support elements of layers in contact intersect at an angle. Depending on the coordination of beam spacing, beam position and beam length, there are one or more coupling grids. To achieve material compaction, the start and / or end points of the support elements in the crossing area can be tapered in height on one or both sides.

The material of the nodes (points of contact / surfaces) can differ from that of the surface of the support elements.

The layer material formed according to the invention consists of at least two layers arranged one above the other. Adjacent layers are in contact with each other via nodes (points of contact). Adjacent layers can have the same or different designs. In particular, there are embodiments in which layers have different material properties.

As mentioned, the layer material can have a sound radiation-neutral end layer in order to provide a cover. This final layer can consist, for example, of thin foils, nonwovens, fabrics, foamed flat materials. The cover acts against mechanical stress and / or heat / cold, aggressive media. It is also possible to install the material between two surfaces.

The individual layers are attached to one another or the layer material is attached to the flat sound-emitting element, preferably by means of adhesive, in particular by means of melt, reaction, UV-curing, contact and pressure-sensitive adhesive systems. An alternative ultrasonic welding represents this.

The layered material can be produced as a molded part or as a flat semi-finished product. Corresponding cuts can be made, for example, by laser or water jet cutting techniques.

Elastomers are used as the preferred material for the carrier elements, in particular made of plastic, non-flowing, especially polyisobutyl.

The invention is described below using exemplary embodiments in conjunction with the drawing. Show it:

FIG. 1 shows a spatial view of a first embodiment of a laminate material part consisting of several layers;

FIG. 2 shows a second embodiment of a layer material part consisting of several layers,

Figure 3 is a transverse view of the part of Figure 2;

Figure 4 is a longitudinal view of the part of Figure 2;

FIG. 5 shows a plan view of a further embodiment of a layer material part;

FIG. 6 shows a plan view of yet another embodiment of a layered material part,

FIG. 7 shows an enlarged spatial detailed view of a layered material part, which is essentially correspond to the embodiment of FIG. 1;

Figure 8a-g seven different embodiments of a layer material in section;

Figure 9a-k eleven different embodiments of carrier elements for layer materials;

FIG. 10 shows a spatial view of a further embodiment of a layered material part; and

Figure 11 is a spatial view of yet another

Embodiment of a layered material part.

The layered material part shown in FIG. 1 in a three-dimensional view has a rectangular shape and consists of five layers arranged one above the other, each consisting of grid elements 1 and 2, which are arranged at right angles to one another and form nodes 3 at their crossing points. Adjacent layers are in contact with one another via their nodes 3.

FIG. 2 shows an embodiment in which the layered material part is slightly curved in the longitudinal and transverse directions. In this embodiment, too, several layers of carrier elements 2, 3 crossing at right angles are arranged one above the other, with more layers being arranged one above the other in the central region of the part than in the edge region 4. The side view of FIG. 3 shows that seven layers are arranged one above the other in the central region are, while there are only four in the edge regions 4. The side view of FIG. 4 shows the same embodiment, but here the end region on the right in FIG. 4 has the same number of layers as that has middle area. In this embodiment too, the layers are composed of support elements 1, 2 arranged in a lattice shape, which intersect at a right angle. Adjacent layers are in contact with one another via the corresponding nodes 3.

In the embodiment of Figure 5, the support elements 1 a layer extending circular while the carrier elements 2 extend ^this' layer radially. Here again, nodes 3 are formed.

Figure 6 shows an embodiment; in which the carrier elements 1 of a layer extend in a spiral or involute form, while the other carrier elements 2 of this layer extend radially. Here again, nodes 3 are formed.

In the embodiment shown in FIG. 7, a total of seven layers are arranged one above the other. One layer consists of a family of carrier elements 1, 2, which in this embodiment are arranged in a layer parallel and at a distance from one another. The carrier elements of adjacent layers are arranged at right angles to one another. This results in nodes 3 at the points of contact of the carrier elements of adjacent layers 6. At 5, an obliquely arranged strut is shown, which serves to stabilize the layer material. Furthermore, 6 support points are shown in order to reduce the span of the support elements between two contact points. For these support points 6, the rectified support elements 2 are in contact with one another.

FIG. 8 shows various exemplary embodiments of the structure of the layer material. In the embodiment of Figure 8a the carrier elements 1, 2 of a layer are arranged parallel to one another and at a distance from one another. The carrier elements of adjacent layers are arranged at right angles to one another, so that the layer structure shown in FIG. 8a results. FIG. 8a also corresponds to a case in which foils are arranged between the carrier elements of the individual layers.

In FIG. 8b, essentially the same structure has been chosen, with the carrier elements 1, 2 of adjacent layers being arranged at right angles to one another.

In the embodiment of FIG. 8c, the carrier elements are tapered at the contact points, so that there is a closer distance from adjacent layers.

In the embodiment of FIG. 8d, the layer material is curved, this curvature being pronounced in each individual layer.

The embodiment in FIG. 8e shows carrier elements of different layers which are displaced relative to one another.

According to FIG. 8f, struts 5 are provided as separate transfer supports.

Finally, the embodiment of FIG. 8g shows a stratification of different heights, which is less in the edge areas than in the middle area.

FIG. 9 shows different cross-sectional contours of carrier elements, FIG. 9k showing a longitudinal view of a carrier element which is composed of different materials over its length. Figure 9a shows a rectangular and an elliptical cross-sectional shape. Figure 9b shows a square, circular, hexagonal and teardrop-shaped cross-sectional shape. Figure 9c shows a hollow cross-sectional shape, while Figure 9d shows a cross-sectional shape made of solid material.

According to FIG. 9e, the cross section is composed of a large number of individual threads or individual fibers, so that the shape of a "strand" (bundle) results. According to FIG. 9f, the cross section consists of a jacket and a core. In FIG. 9g, gaseous inclusions in the form of bubbles or tubes are provided. ^'Referring to Figure 9h are solid or liquid inclusions in the form of granules, chips, filaments, fibers, etc. provided balls. The embodiments of FIGS. 9i and 9j show different materials in a cross section.

Finally, FIGS. 10 and 11 show two schematic spatial representations of further embodiments of layer materials, the layer material being formed from several layers in FIG. 10, in which the carrier elements partially assume the same and different angular positions. FIG. 11 shows a case in which the carrier elements of the different layers are arranged essentially parallel to one another.

Points of contact can be realized via electromechanical elements.

In the case of moving (rotating) parts, the material can be attached using positioning aids.

The rod-shaped carrier elements can expediently also consist of several layers, i.e. Show laminates.

Claims

claims

1. layered material for influencing the vibration, radiation and / or sound behavior of, in particular, flat sound-radiating elements, characterized in that it has at least two layers (6) arranged one above the other and connected to one another, each consisting of rod-shaped support elements (1 , 2), the start and end points of which are connected to other support elements (1, 2) or in the state installed on the sound-radiating element, and the support elements (1, 2) of the same layer (6) and / or arranged at an angle thereto an adjacent layer (6) form nodes (3), and that the material of the support elements

(1,2) is plastic, plasto-elastic or elastic.

2. Layered material according to claim 1, characterized in that the carrier elements (1 or 2) of a layer (6) are arranged in straight or kinking lines which form parallel or angled groups.

3. Layer material according to claim 1, characterized in that the carrier elements of a layer are arranged in a lattice shape.

4. Layer material according to one of the preceding claims, characterized in that between two carrier elements (1, 2) having layers (6) a sound radiation neutral intermediate layer is arranged.

5. Layer material according to one of the preceding claims, characterized in that it has a sound-neutral end layer.

6. Layer material according to one of the preceding claims, characterized in that the nodes (3) have a coating.

7. Layer material according to one of the preceding claims, characterized in that the nodes (3) are tapered.

8. Layered material according to one of the preceding claims, characterized in that the rod-shaped carrier elements (1, 2) are round, elliptical, polygonal in cross-section in an irregular or regular manner.

9. Layered material according to one of the preceding claims, characterized in that the carrier elements (1, 2) are designed to be full, hollow and / or coated in cross section.

10. Layered material according to one of the preceding claims, characterized in that the carrier elements consist of individual threads or individual fibers or have such.

11. Layered material according to one of the preceding claims, characterized in that the carrier elements (1, 2) have inclusions of gaseous, solid and / or liquid materials.

12. Layer material according to one of the preceding claims, characterized in that the carrier elements (1, 2) are longer than their largest cross-sectional dimension.

13. Layered material according to one of the preceding claims, characterized in that the carrier elements have electro-mechanical elements (actuators / reactors).

14. Layer material according to claim 4, characterized in that the sound radiation neutral intermediate layer contains electrical conductors, electrical connections and / or electromechanical elements.

15. Layered material according to claim 13 or 14, characterized in that the electromechanical elements perform and / or record movements perpendicular and / or parallel to the corresponding point of the surface element.

16. Layered material according to one of the preceding claims, characterized in that the material of the carrier elements is generally, statistically or periodically high.

17. Layered material according to one of the preceding claims, characterized in that the carrier elements have segments with different properties in the longitudinal direction.

8. Layered material according to one of the preceding claims, characterized in that the rod-shaped carrier elements (1, 2) consist of several layers.