WO2021175667A1

WO2021175667A1 - Reflector for waterborne sound transducers

Info

Publication number: WO2021175667A1
Application number: PCT/EP2021/054466
Authority: WO
Inventors: Torben PARDUN; Jakob Riemann; Kilian HELFMEIER
Original assignee: Atlas Elektronik Gmbh; Thyssenkrupp Ag
Priority date: 2020-03-04
Filing date: 2021-02-23
Publication date: 2021-09-10
Also published as: DE102020202776A1

Abstract

The invention relates to a reflector (20) for waterborne sound transducers (22), comprising a reflection plate (24) and a guide (26) for securing the reflection plate (24) to a watercraft (28). The reflection plate (24) is designed to reflect waterborne sound waves. A damping element (30) is arranged between the guide (26) and the reflection plate (24), wherein the damping element (30) has a progressive stiffness characteristic curve.

Description

Reflector for water-borne sound transducers

description

The invention relates to the attenuation of (water-borne) reflectors for water-borne transducers, in particular those water-borne transducers which are used for sonar applications.

Reflectors are used to reflect sound waves onto water-borne sound transducers arranged adjacent to the reflector in order to increase (ideally to double) the resulting signal strength of the water-borne sound waves. This enables improved detection by means of the water-borne sound transducer. The reflector is connected to a water vehicle, e.g. a ship or a submarine. The watercraft generates vibrations that are transmitted to the water-borne sound reflector. Due to the vibrations, however, the water-borne sound reflector in turn generates sound waves that overlay the water-borne sound waves that are actually to be detected and thus interfere with the actual detection.

The object of the present invention is therefore to create an improved concept for reflectors for water-borne sound converters.

The object is achieved by the subject matter of the independent claims. Further advantageous embodiments are the subject of the dependent claims.

Exemplary embodiments show a reflector for water-borne sound transducers with a reflection plate which is designed to reflect water-borne sound waves and a (first) damping element. The damping element connects the reflection plate to a watercraft (at least mechanically). Furthermore, the damping element has a progressive stiffness characteristic. Due to the progressive stiffness characteristic, the reflection plate is softly dampened with small deflections. The greater the deflection, the stiffer (or harder) the damping becomes. The damping element can be direct or indirect Establish a connection with the watercraft. The reflector can thus have a guide which connects the reflection plate to the watercraft via the damping element, the damping element being arranged between the guide and the reflection plate. The damping element here creates an indirect connection to the watercraft.

The idea is to decouple the reflector (more precisely the reflection plate) from the (mechanical) vibrations of the watercraft through the progressive stiffness characteristic of the damping element. Vibrations with small deflections are thus absorbed by the damping element and the reflection plate itself experiences an even smaller deflection. In the case of larger deflections, the reflection plate is nevertheless reliably damped before the reflection plate comes into contact, for example, with the watercraft or a suspension.

In exemplary embodiments, the damping element has a base and a top surface. The base surface and the top surface are each aligned parallel to the reflection plate, the base surface having a larger surface area than the top surface. In other words, the damping element tapers towards the reflection plate or towards the guide. Progressive damping is achieved through the taper.

In exemplary embodiments, the damping element forms a cone, in particular a truncated cone, the cone tapers, in particular converging towards the reflection plate. An axis of rotation of the cone can be oriented perpendicular to the reflection plate. Alternatively, the damping element can form a pyramid or a truncated pyramid, the pyramid or the truncated pyramid converging towards the reflection plate. In other words, the cone or the pyramid / the truncated pyramid tapers starting from its bearing surface to the reflection plate. Progressive damping is achieved by tapering the geometric shapes.

In exemplary embodiments, a guide, in particular perpendicular, is passed through the reflection plate. The reflection plate is along the guide movably arranged. The guide runs in particular parallel to an effective direction of the damping element. The guide prevents the reflection plate from executing a movement in the other spatial directions in addition to the desired movement in the reflection direction, ie in the direction of the water-borne sound transducer.

In exemplary embodiments, a second damping element is arranged between the guide and the reflection plate, the second damping element having a progressive stiffness characteristic, the second damping element being arranged on a side of the reflection plate opposite the (first) damping element. So that the second damping element can be arranged between the reflection plate and the guide, the guide can have a T-shape on the side opposite the first damping element. This means that the reflection plate is attenuated both in the direction of the water-borne sound transducer and in the direction of the watercraft (along the guide). Furthermore, the oscillation of the reflection plate after a (single) excitation is dampened by the opposing damping elements.

In other words, the second damping element can be designed in the same way as the damping element. That is to say, in particular, that the second damping element can have a base surface and a top surface which are each aligned parallel to the reflection plate, the base surface having a larger surface area than the top surface. Furthermore, the second damping element can form a cone, in particular a truncated cone, wherein the cone tapers, in particular tapers towards the reflection plate. Alternatively, the second damping element can form a pyramid or a truncated pyramid, the pyramid or the truncated pyramid converging towards the reflection plate.

The reflection plate can thus be fixed along the guide by the damping element and the second damping element and held in position by the guide perpendicular to the guide. In exemplary embodiments, the guide has a further damping element, in particular an O-ring, surrounding the reflection plate. The reflection plate is damped in the other (two) spatial directions in which the reflection plate should not move by the further damping element. The further damping element is advantageously more rigid than the damping element and / or the second damping element. The further damping element can be stiffer on average than the damping element and / or the second damping element. Thus, the reflection plate is guided in a stable manner perpendicular to the guide, along the guide it is initially softly damped by means of the damping element and optionally the second damping element and, as the deflection increases, it is dampened more rigidly or harder.

Analogously, a method for positioning a reflector for water-borne sound transducers is shown with the following steps: providing a reflection plate which is designed to reflect water-borne sound waves; Connecting the reflection plate (24) to a watercraft (28) by means of a damping element (30), the damping element having a progressive stiffness characteristic.

Preferred exemplary embodiments of the present invention are explained below with reference to the accompanying drawings. Show it:

1: a schematic sectional illustration of a reflector for water-borne sound transducers in a side view;

2: a schematic sectional illustration of a detail of the reflector in a side view according to exemplary embodiments;

3: a schematic sectional illustration of the detail of the reflector in a side view according to further exemplary embodiments; and

4: a schematic perspective illustration of a damping element arrangement with a multiplicity of damping elements, the damping elements having a progressive stiffness characteristic. Before exemplary embodiments of the present invention are explained in more detail below with reference to the drawings, it is pointed out that identical, functionally identical or identically acting elements, objects and / or structures in the different figures are provided with the same reference numerals, so that those shown in different exemplary embodiments Description of these elements is interchangeable or can be applied to one another.

1 shows a schematic representation of a reflector 20 for water-borne sound transducers 22. The reflector 20 has a reflection plate 24 which is fastened to a watercraft 28 by means of two damping elements 30. To illustrate this, a schematic outer skin of the watercraft 28 is shown as an example. Instead of the damping elements 30, the reflection plate 24 can also be attached to the watercraft 28 by means of a suspension (not shown). The damping elements 30 can then be arranged between the reflector and the suspension. The suspension can also form the shock mount of the reflector. One possible configuration of the suspension is a (laterally open) U-shape.

The water-borne sound transducers 22 can be (mechanically) connected to the watercraft outside the cutting plane. This connection can lead through the reflection plate or laterally past the reflection plate.

A (first) damping element 30 is arranged between the reflection plate 24 and the watercraft 28. The reflection plate 24 rests on the damping element 30. Optionally, a further damping element 30 is arranged between the watercraft 28 and the reflection plate 24. In other words, the reflector 20 can then be constructed symmetrically.

FIG. 2 shows a section of the reflector 20 from FIG. 1 in an exemplary embodiment. A guide 32 is shown here, which is passed through the reflection plate 24. The water-borne sound converters 22 (or at least one water-borne sound converters) are connected to the watercraft 28 by means of the guide 32. The reflection plate 24 is along the guide 32, ie in the direction of Water-borne sound transducer, that is to say in the z-direction, is movably mounted on the guide 32. In addition to the damping element 30, a symmetrically arranged damping element 30a can be provided, in particular to establish symmetry. The symmetrically arranged damping element 30a is advantageously identical to the damping element 30. The guide 32 can be connected to the watercraft 28 in order to fasten the reflection plate 24 to the watercraft 28. The guide 32 can, however, also be arranged on the suspension (not shown) so that the guide is indirectly connected to the watercraft 28 via the suspension. In order to form a support surface for the damping elements 30, 30a, the guide 32 can have a widening on one side. In order to form the widening, the guide 32 is shaped, for example, T-shaped. A widening is understood to mean an enlargement of the area of the guide 32.

FIG. 3 shows the detail of the reflector 20 from FIG. 2 in further exemplary embodiments. Here, a second damping element 34 is arranged between the guide 32 and the reflection plate 24. A second symmetrically arranged damping element 34a can also be provided in this exemplary embodiment. In order to exert a force effect of the guide 32 on the second damping element 34, the guide can have a (further) widening on a side facing the reflection plate 22. Here too, the widening can be T-shaped. Together with the widening already shown in FIG. 2, the guide 32 is then designed to be double T-shaped. The second damping element 34 and also the second symmetrically arranged damping element 34a can then be arranged between the reflection plate 22 and the widening of the guide 32. The widening of the guide means that part of the guide can run parallel to the reflection plate. The second damping element (optionally also the second symmetrically arranged damping element) is arranged between this part of the guide and the reflection plate.

In order to be able to freely set a distance between the reflection plate 24 and the water-borne sound transducers 22, a recess 36 is provided in the reflection plate 24, in which the second damping element 34 (as well as the optional second symmetrically arranged damping element) are arranged. So that magnifies Second damping element 34 does not cover the distance between the water-borne sound transducers 22 and the reflection plate 24.

In a further exemplary embodiment, which is independent of the actual configuration of the guide 32, the guide 32 has, in particular circumferentially, a further damping element 38 for the reflection plate. The further damping element 38 is, for example, an O-ring. The further damping element 38 can be arranged within a bore 40 through which the guide 32 is passed. Thus, the further damping element 38 can dampen a movement of the reflection plate 24 in the x-direction and in the y-direction. In addition, it is advantageous if the further damping element 38, in particular on average, is stiffer than the damping element 30 or the second damping element 34. The x-direction and the y-direction are perpendicular to the desired direction of movement (z-direction) of the reflection plate 24 , which points in the direction of the water-borne sound transducer 22 or in the direction of the watercraft. The further damping element 38 can be used in any configuration of the reflector 20 with the guide 32 separately from the further features shown in FIG. 3.

4 shows a schematic perspective illustration of a damping arrangement 42. The damping arrangement 42 comprises a multiplicity (here 8) damping elements 30 and a multiplicity (here also 8) symmetrically arranged damping elements 30a. The damping arrangement 42 can have an opening 44 through which the guide can be passed. The damping arrangement can thus provide the required number of damping elements. The damping arrangement can, for example, rest on the guide and / or (in the recess) on the reflection plate. Analogously, the damping arrangement can also provide the second damping elements 34 and optionally the symmetrically arranged second damping elements 34a.

The design of the damping elements 30, 34, 30a, 34a can also be seen in FIG. 4. The damping elements 30, 34, 30a, 34a can have a base surface 46 and a top surface 48. The base surface 46 and the top surface 48 run parallel to the reflection plate. In other words, one runs Direction of use of the damping elements perpendicular to the reflection plate, so that the damping elements 30, 34, 30a, 34a can dampen a movement of the reflection plate in the direction of the water-borne sound transducer. The damping element in FIG. 4 is, for example, shaped as a cone, here in the form of a truncated cone. The cone can run from the guide to the reflection plate. Alternatively, the damping element 30, 34, 30a, 34a can also be pyramid-shaped or shaped as a truncated pyramid. In other words, the damping element 30, 34, 30a, 34a tapers in order to maintain the progressive stiffness characteristic.

The disclosed (water) sound transducers are designed for use under water, in particular in the sea. The sound transducers are designed to convert water-borne sound into an electrical signal (e.g. voltage or current) corresponding to the sound pressure, the water-borne sound signal. In addition, the sound transducers are designed to convert an applied electrical voltage into water-borne sound. The sound transducers can accordingly be used as water-borne sound converters and / or as water-borne sound transmitters. The sound transducers have a piezoelectric material, for example a piezoceramic, as the sensor material. The transducers can be used for (active and / or passive) sonar (sound navigation and ranging). The sound transducers are not suitable for medical applications.

Although some aspects have been described in connection with a device, it goes without saying that these aspects also represent a description of the corresponding method, so that a block or a component of a device is also to be understood as a corresponding method step or as a feature of a method step. Analogously to this, aspects that have been described in connection with or as a method step also represent a description of a corresponding block or details or features of a corresponding device.

The above-described embodiments are merely illustrative of the principles of the present invention. It is to be understood that modifications and variations of the arrangements and described herein can be made Details will be apparent to other experts. It is therefore intended that the invention be limited only by the scope of protection of the following patent claims and not by the specific details presented herein with reference to the description and explanation of the exemplary embodiments.

List of reference symbols:

20 reflector 22 water-borne sound transducer 24 reflection plate

28 watercraft 30 damping element 32 guide

34 second damping element 36 recess

38 further damping element 40 bore 42 damping arrangement 44 opening 46 base area of the damping element

48 Top surface of the damping element

Claims

1. A reflector (20) for water-borne sound transducers (22) having the following features: a reflection plate (24) which is designed to reflect water-borne sound waves; a damping element (30) which connects the reflection plate (24) to a watercraft (28), the damping element (30) having a progressive stiffness characteristic.

2. Reflector (20) according to claim 1, wherein the damping element (30) has a base surface (46) and a top surface (48) which are each aligned parallel to the reflection plate (24), the base surface (46) having a larger surface area has than the top surface (48).

3. reflector (20) according to any one of the preceding claims, wherein the damping element (30) forms a cone, wherein the cone tapers, in particular tapers to the reflection plate (24).

4. reflector (20) according to any one of the preceding claims, wherein the damping element (30) forms a pyramid or a truncated pyramid, wherein the pyramid or the truncated pyramid runs to the reflection plate (24).

5. reflector (20) according to any one of the preceding claims, with a guide (32) which connects the reflection plate via the damping element (30) to the watercraft, wherein the damping element is arranged between the guide and the reflection plate.

6. reflector (20) according to one of the preceding claims, wherein a guide (32), in particular perpendicular, is passed through the reflection plate (24).

7. reflector (20) according to claim 5 or 6, wherein between the guide (32) and the reflection plate (24) a second damping element (34) is arranged, wherein the second damping element (34) has a progressive stiffness characteristic, the second damping element (34) is arranged on a side of the reflection plate (24) opposite the damping element (30).

8. reflector (20) according to claim 7, wherein the second damping element (34) has a base surface (46) and a top surface (48) which are each aligned parallel to the reflection plate (24), the base surface (46) having a larger one Has surface area than the top surface (48).

9. reflector (20) according to claim 7 or 8, wherein the second damping element (34) forms a cone, wherein the cone tapers, in particular tapers to the reflection plate (24).

10. reflector (20) according to claim 7 or 8, wherein the second damping element (34) forms a pyramid or a truncated pyramid, wherein the pyramid or the truncated pyramid runs to the reflection plate (24).

11. Reflector (20) according to one of claims 5 to 10, wherein the guide (32) has a further damping element (38), in particular an O-ring, to the reflection plate (24).

12. reflector (20) according to claim 11, wherein the further damping element (38) is stiffer than the first and / or the second damping element.

13. A method for producing a reflector for water-borne sound transducers (22), comprising the following steps: providing a reflection plate (24) which is designed to reflect water-borne sound waves;

Connecting the reflection plate (24) to a watercraft (28) by means of a damping element (30), the damping element (30) having a progressive stiffness characteristic.