HU231115B1 - Equipment for the utilization the energy of a free surface liquid, in particular watercourse - Google Patents

Description

Equipment for utilizing the energy of a free-flowing liquid, in particular running water

The present invention relates to an apparatus for utilizing the energy of a free-flowing fluid, in particular running water, which comprises a row of vanes comprising vanes capable of moving and rotating in an endless transmission path fixed to a support structure and a drive shaft in operative communication with the vanes.

The use of renewable energy sources is becoming an increasingly urgent problem worldwide, partly due to the depletion of fossil fuels and partly due to the increasing burden of air pollution,

One natural energy source that does not diminish during utilization is flowing water. Hydroelectric power plants can be installed and operated most economically in places where the waterfall has a high fall height, ie in the mountains (high-drop turbines), or a significant fall height can be created by a dam. It is not possible to build large-scale hydroelectric power plants in a flat area, and the installation of dams can have serious environmental damage, despite the high investment costs.

Rivers with a high mass flow, relatively slow and even very low fall heights offer a usable source of water energy, and the efforts and solutions for the utilization of their energy can be divided into three groups.

21655 / KO

SZTNH «ÍÓ02Ő5256

One possibility is to use an impeller, as exemplified by the XX. at the beginning of the century e.g. a ship mill widely used on the Danube and Tisza. The immersion of the blades of ship mills is limited, they build up congestion pressure, so the recoverable energy is small.

The next group includes axial turbines, which are used mainly in connection with the extraction of tidal water motion energy. However, different flow rates are difficult to make optimal use of with the same equipment.

The rotating shaft is under water, so the generator is also submerged, which makes operation and maintenance difficult.

The third group includes systems with row-mounted blades, and although many proposals have been made for their construction, at least significant implemented solutions are not known.

GB 7568 A method for extracting energy from flowing water comprising blades fixed rigidly and perpendicular to its longitudinal direction to an endless chain is disclosed in the patent specification, wherein the chain is passed through a barrel, above the water surface, from which the rotation of its central shaft can be transformed e.g. into electrical energy. Only the lower branch of the endless chain, shorter than the upper, is immersed in the water. The blades are driven by congestion pressure, the immersion is limited in this case as well, the position of the blades cannot be controlled, so with the solution rational, efficient energy extraction is practically not possible.

The hydraulic motor disclosed in GB 403 607 has a row of vanes arranged between two endless chains passed through sprockets with vertical axes. The trajectory and travel of the blades in the drive range are vertical, i.e. perpendicular to the flow, due to which the component of the direction of movement of the force generated on the number profile is relatively small, the available energy extraction efficiency hardly allows rational practical application.

An apparatus for extracting electrical energy from a flowing medium is described in U.S. Pat. No. 4,049,300. U.S. Pat. No. 4,092,607, which discloses the use of a series of vanes mounted between an endless chain running through a pair of lower and upper horizontal axle sprockets. Although the movement of the blades on one forward branch of the blade row of the apparatus provides favorable energy recovery efficiency, the other, the return branch, produces a loss. The practical application of the equipment is not likely to result in an economical solution.

According to Spanish publication ES 2274679 A1, the endless chain of a device for obtaining energy from flowing water, comprising blades, has two sections perpendicular to the flow, directed downwards and upwards. With this solution, the blade angle cannot be changed. A disadvantage is that the effective force generated by the two sections must overcome a considerable loss of mechanical resistance in order to produce usable power on its shaft.

The blades of the equipment for extracting the energy of flowing water, which is also known from the Hungarian patent specification HU 87934 B, is also infinite-chained, so that the performance cannot be optimized. Another problem is that the PTO shaft is under water, which makes it difficult to apply in practice.

SUMMARY OF THE INVENTION It is an object of the present invention to provide a series of paddle-bladed equipment for utilizing the flowing energy of a free semi-colored flowing liquid, in particular high mass flow, relatively slow, low drop rivers, which enables the most efficient extraction of energy, eliminating the disadvantages we have described in detail the known solutions for this purpose.

The invention is based on the recognition that the trajectory or direction of travel of the paddle row must be chosen so that all the paddles immersed in the water do not generate a buoyancy but a buoyancy, since its velocity component can be one and a half to two and a half times the buoyancy.

We have also discovered that it is important for efficient energy recovery that the return branch of the paddle row and the power take-off shaft of the equipment are located in an air space with virtually negligible resistance, and that the water-immersed portion of the entire paddle row substantially exceeds the airborne return. and there should be sufficient distance between the rows of paddles behind each other to arrange the flow from the previous paddle to the next paddle row, which can be achieved by selecting the endless trajectory with one of its vertices deep into the triangular trench. This ensures that the direction of travel of the blades can be at an angle of 090 ° to the direction of water flow, which allows an optimal power transmission blade position to be set. Finally, we have realized that by providing the controllability of the angle of the blades, the current flow parameters of the river can be adjusted, thus further optimizing the efficiency of energy extraction.

Based on the above findings, the object is achieved according to the invention by means of an apparatus for utilizing the energy of a free-flowing liquid, in particular running water, having a series of vanes capable of moving and rotating in an endless transmission path fixed to a support structure. and a pivot-shaped control path arranged parallel to the transmission path and having a closed curved shape identical to its shape, allowing the blades to rotate through a blade angle adjusting device, where the blades have an arcuate surface, the transmission path having a closed arc. , which has

- a first forward section obliquely downwards and in force relative to the fluid flow direction (a),

- a first forward section, a second forward section from the lower end upwards and forwards; and

- the return section of the second forward section extending from the end to the upper end of the first forward section and the position of the control track relative to the transmission path can be changed without interrupting the operation of the equipment.

The essence of the device is that the return section extends above the liquid surface.

Note that the direction of the transmission path corresponds to the direction of travel of the blades.

A preferred embodiment of the device is characterized in that the blades have in their central region a slot opening to one of their longitudinal edges, through which a pond a flexible force transmission means is passed and is fixed to the blade inside the slot so as to allow the blade to rotate; and the transmission means has means for converting the forward movement of the transmission means driven by the paddle row formed by the vanes in the region of the intersection of the forward section of the transmission path and the second return section into an axial rotational movement.

Preferably, the transmission means is a chain, the means for converting the forward movement of which into the rotational movement of the shaft is a sprocket through which the chain is passed, but as a transmission means other linear flexible means, ph belt, etc. can also be used.

According to one embodiment, the device for guiding the chain has a rigid guide rail with an opening of a shape corresponding to the shape of the transmission path, inside which rollers are arranged on its masonry as the row of blades passes, the axes of which are guided through the chain and rotate in a blade. they are embedded in a permissive way.

Preferably, the guide rail is formed by a C-profile made of material, in particular steel. It is also preferred that the width of the blade gap is selected to exceed the combined width of the chain and the guide rail; and if the control paths are rigid; they have a guide rail with an opening facing the blades, preferably a metal U-profile.

It is also advantageous if the blade angle adjusting device has a rigid spacer member, preferably in the form of a triangular plate, connected to the outer edge edges of the blades clamping fastening member, a rod fixed thereto and a longitudinally displaceable slider or roller therein, preferably in the guide rail. it fits movably in its longitudinal direction.

According to a further aspect of the invention, the blades are rectangular, one surface convex and the other surface concave, connected to the transmission means, in particular to a chain, in a longitudinal geometric center plane perpendicular to their side surface, and the blade gap parallel to their side surface. designed and its height exceeds the half-width of the blade. However, the blade may be square or even trapezoidal in shape and the side facing the direction of flow is concave. Since at the turning point of the first and second forward sections of the transmission path, the inlet and outlet edges of the blades are reversed, i.e., the flow direction relative to the blade is reversed, it is expedient for the blade section to be symmetrical to their transverse center axis.

The pulleys of the PTO shaft, the guide rail of the transmission device and the control rails of the control tracks are connected to a support structure.

According to a further preferred embodiment, the control tracks of the control tracks are fixed to the support structure in a manner suitable for changing their position relative to the track; the control path and the transmission path can be moved in a plane parallel to each other.

It is advisable if the support structure is a floating body; and if the device has a support structure in a fixed position, in particular a support frame.

Finally, according to another preferred embodiment, in the case of curved surface blades, the blade cross-section between the straight line connecting the inlet and outlet edges and the blade angle between the flowing medium, in particular running water, is set so that the direction of protection is at least approximately at the blade inlet tangent. , where the sketch line is the geometric position of the center of the circles inscribed in the blade cross section and the main direction is the vector of the difference between the flow direction of the fluid, in particular running water, and the blade travel direction, this is the energy - optimal blade angle.

The invention will now be described in more detail with reference to the accompanying drawings, which show a preferred embodiment of the device and some structural details. In the drawings: Figure 1 is a schematic side view of the apparatus;

Figure 2 is a perspective view of the apparatus of Figure 1;

Figure 3 is an enlarged perspective view of the environment of the transmission wheel of the apparatus;

Fig. 4 shows a detail A marked in Fig. 1 on a larger scale;

the. Figure 5 is a plan view of a blade of the apparatus with a sectional power transmission device attached thereto;

Figure 6 is a sectional view taken along line B-B in Figure 5;

Figure 7 is an enlarged view taken in the direction of the arrow C in Figure 5;

Fig. 8 shows the detail D marked in Fig. 5 on a larger scale;

Figure 9 is a detail E as indicated in Figure 6;

Fig. 10 shows the detail F marked in Fig. 6 on a larger scale;

Figure 1L is an enlarged view of detail G marked in Figure 5;

Figure 12 is an enlarged scale view of a blade located in the first forward section of the transmission path;

Figure 13 also shows the position of a vane in the second forward section of the transmission path on a larger scale.

The device according to the invention is connected to a support structure in a fixed position, such as a frame structure, which is not shown in the figures for the sake of clarity. For example, the support structure may be located at a point anchored on river water between its floating bodies and fixed to them.

As shown in Figures 1 and 2, the device has rows of paddles I to which a drive device in the form of a closed curve, preferably flexible and operatively connected to a power take-off shaft 3, is connected in the case of the present embodiment to a chain 2 which is passed through a sprocket 4 with teeth 4a (see Fig. 3) firmly attached to the shaft. The shaft 3 is rotatably mounted at its ends in bearings 5 and 6 known per se, which are firmly attached to a support structure (not shown). The chain links or chain members of the chain 2, as can be seen in particular in FIG. 9, which will be described in more detail later, delimiting the gap 2c. They comprise side plates 2b and the teeth 4a of the sprocket 4 fit into the slots 2c, whereby the chain 2 moving in the direction of the arrow x rotates the sprocket 4 and with it the shaft 3 in the direction of the arrow b marked in FIG. At the joints of the adjacent chain links, shafts 10a and 10b are sewn, passing through the sections 10a between the two laths 1 of the chain 2; the shaft ends of the shafts 10b are rotatably mounted in the narrow side plate of the blade 1, as can be seen in particular in Figures 8 and 9.

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Figure 1 shows a side view of a preferred shape of the endless trajectory of the blades 1, i.e. the transmission path. This shape is an isosceles triangle with one vertex ht at depth M below water level v; the flow direction of the water is indicated by the arrow, The flow side of the triangle corresponds to the first forward section la of the transmission path: Here the l-blades lined up line move obliquely from top to bottom in the direction of the arrow x, then turn at the bridge point and the row of blades y arrow, in the direction of obliquely moving from bottom to top ah? points. This is the second Ib forward section of the transmission path and the trajectory of the section between points In and he.

The second forward section Ib at the apex of the triangle already above the water level v passes to the return section II of the transmission path in the air, where the row of blades moves horizontally to the sprocket 4 and turns downwards again in the first forward section 1a. The angles a and δ of the force transmission path, i.e. the forward sections 1a and 1b of the trajectory, are the same as in this example, preferably about 45 ^ -0 ^, but may be different, and the respective conditions (fall height, kinetic energy density, level) can vary widely. It is noted that the combined length of the forward sections 1a, 1b immersed in water is preferably substantially longer than the length of the air return section II, which in this example is the longest side of the isosceles triangle.

As can be clearly seen in Figures 1-3, the chain 2 is guided by rollers 11 in a guide rail 7 firmly attached to a support structure (not shown); each roller 11 is mounted on a shaft I Db, which extends from the inner narrow side plate of the blade 1 and is guided through the chain 2, carrying it by means of the advancing movement of the blades 1. Each of the vanes 1 rotates about its respective axis 10b.

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The device also has two control paths 111¾ IHb from the middle guide track, i.e. on either side of the guide rail 7, which are formed by the guide rails 8, 9 according to this example. These are also fixed to the support structure (not shown), but not fixedly, but in such a way that the longitudinal axis f of the blade 1 can rotate, which, as will be explained in detail later, allows the blades l to flow in that direction (Fig. 1). ), so as to control the movement of the entire row of vanes. The closed curve - Here triangular - shaped 8.9 guide rails are continuous, not interrupted.

Hereinafter referred to as 1 »6. and with reference to Figures 8, 9, the exemplary construction of the connection of the blades 1 and the chain 2 and the contempt in the guide rail 7 will be described in detail.

The construction shown in perspective on a larger scale in Figure 3 is shown in Figure 5.6. and Figures 8, 9 are partly in section and partly in view. Accordingly, as already mentioned below, a shaft 10b rotatably mounted in each of the blades 1 extends transversely in the front view in a rectangular shape. I of a gap formed in the central axis of the geometric transverse edge I, which starts from below and ends above the longitudinal geometric center axis f of the paddle 1. The axis 10b falls in this geometric center axis f.

Since the inlet and outlet edges of the blades 1 are reversed at the apex of the bridge at the apex of the first feed section 1a and the second feed section Ib of the transmission path, the flow direction relative to the blade 1 is reversed. Accordingly, according to the present embodiment, the section of the blades 1 is symmetrical about the transverse axis e, as can be clearly seen in FIG.

The shaft 10b passes through the chain 2 extending through the gap 1a, i.e. the side panels 2a, 2b of each chain member, between them the gap 2c, which, as mentioned, fits the teeth 4a of the sprocket 4 and drives it. At the end of the shaft 10b extending beyond the chain 2 is a roller 11 which fills the guide rail 7, according to this embodiment, a steel C-profile, with a small lateral gap so that it can roll therein. The width I of the gap 1a marked in Fig. 8 exceeds the combined width of the chain 2 and the guide rail 7. The shaft 10b extends through the gap 7a of the C-profile into the interior of the guide rail 7. By means of the shafts 10b, the rollers 11 belonging to the blades 1, which roll in the guide rail 7, only allow movement in the direction of the rail, thus forcing the row of blades to move in the corresponding direction.

In Fig. 7, a paddle 1 provided with a paddle angle adjustment device 13 is shown in a larger side view. The side 20 of the vane 1, viewed from the direction of water flow (also Fig. 1 1), is concave, the other side 21 is convex and ends at its edges at the edges (rounding is allowed). The central region of the blade t is thick enough to accommodate the shaft 10b of the blade 1 and to retain the fixing member 12 for connecting said blade angle adjusting device 13. In the case of the simplest blade profile, it is advisable to form the blade surface facing the flow direction into a concave.

As already mentioned, the individual blades 1 are connected on both sides here to the control tracks IIIa, IIIb formed by the controls 8, 9 by means of a blade angle adjusting device 13, by means of which it is possible to ensure that the blades 1 have different power flow and chain speeds. set the optimal angle with the direction of the track and their direction of travel. The length of the blade angle adjusting device 13 can be varied accordingly, and as a result the distance of the outer end of the blade 1 from the transmission path or the guide rail 7 can be varied. The blades 1 have an optimal position in relation to the flow direction corresponding to the respective water velocity, and this can be adjusted by moving the blade 1 transversely to the flow direction by means of the blade angle adjustment device 13 within its adjustable limits. By varying the length of the blade angle adjuster 13, the range in which the blades can be controlled during operation can be set during operation by shifting the tracks relative to each other when the device is assembled.

The paddle angle adjusting device 13, as shown in particular in FIGS. and 10, 11, a spacer rod 14 rigidly attached thereto and a slider or roller 15 movable thereon in the longitudinal direction of the rod, which fits into the guide rails 8 and 9 formed in this case as steel, The eccentricity of the slider 15 is provided by a spacer 14 which is angularly connected to the blade 1 by means of a fastening member 12. The closed curved shape of the control paths 8, 9 - here is an equilateral triangle in side view - is the same as the central transmission. parallel to the shape of the track and the guide rail 7, and all three tracks run in a vertical plane in the same direction as the flow of water, as indicated above, while the guide rail 7 is in a fixed position, the guides 8, 9 are fixed to the support structure (not shown). that their positions can be adjusted horizontally and fixed at the optimal working point at any given time.

The optimal working point has an optimal blade angle γ as shown in Fig. 12. The concept of the optimal blade angle and the possibility of adjustment of the blades 1 are illustrated in Figures 12 and 13. In these figures, the. The line connecting the inlet and outlet edges of the blade 1, namely the string of the blade 1 with a curved outer and inner surface, is denoted by the reference letter h; in this respect, the leading edge is the edge at which the blade 1 in the home position is.

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flowing medium, in particular flowing water, first and the outlet edge at which the paddle 1 leaves the flowing medium.

The angle γ of the blade 1 is closed by the direction of travel indicated by the arrows x and y and the string h.

Figures 12 and 13 also show the frame line g, i.e. the center line, of the blades 1, which is the geometric position of the centers of the circles which can be written into the blade profile or drawn.

The position angle y is optimal if the direction of contact of the curved frame line g is the same or substantially the same as the blowing direction. The blowing! by direction is meant the direction of the fluid flowing undisturbed in the vicinity of the blade 1, in this example the water, relative to the blade 1. In the coordinate system for blade 1, the direction of blowing is given by the relative water velocity vector, which is the difference between the flow medium, here running water, the velocity vector corresponding to the flow direction x and y, respectively. and in Fig. 13 it is denoted by the reference letter m '.

By adjusting the horizontal position of the guide rails 8, 9 relative to the guide rail 7 (even during operation), the direction of blowing at its inlet edges can be adjusted to the direction of the tangent to the frame line. The blade angle γ is optimal.

The relative positions of the guide rail 7, the guide rails 8, 9 and the blade 1 and the blade angle adjusting device 13, as well as the chain 2 and the rollers 11, are shown in a side view in FIG.

1-10. The apparatus of Figures 1 to 4 operates as follows;

according to Fig. 1, the water flowing in the direction of the arrow keeps the row of blades formed by the blades 1 in a motion corresponding to the arrows x, y and z. Meanwhile, the vanes 1 locally change the flow direction of the fluid, the pressure on the concave side of the vanes near their surface is higher than the ambient pressure, and on the convex side the pressure near the surface is less than the ambient pressure. As a result, a buoyancy force is generated on each blade 1, which creates a force on the blade 1. During the advancing movement of the row of vanes, the movement of the vane 1, which can rotate about the axis Ob 1, forms an angle with the flow direction indicated by the arrow, first descends in the forward section Ja according to the arrow x marked in Fig. 1, then the lowest h; leaving the vertex, it moves upwards in the first return section Ib according to the arrow y, if it already rises above the water level v at the vertex and changes its direction of travel in the direction of the arrow z in the second return section II, it finally returns to the starting point. The chain 2 moved by the row of blades 1 rotates the shaft 3 and the shaft 3 continuously through it, thus extracting the flow energy of the water from the shaft 3; e.g. rotational energy that can be used to generate electricity is displayed.

The beneficial effects of the invention can be summarized as follows:

The paddles enter the water such that the relative water velocity at the inlet paddle edge is tangent to the skeleton line. In water forced into an arcuate trajectory along the paddle, local velocities increase relative to ambient pressure on the concave side and decrease on the convex side. The resultant force resulting from the difference in motion is nearly perpendicular to the blade section string. Thus, the device according to the invention takes advantage of the physical phenomenon that the moving component of the force thus generated is greater than the force due to the throttling pressure on the known impeller blades, and the device according to the invention works much more blades at a time than e.g. the number of simultaneously reacting blades of a water wheel. The leading and trailing edges of the blades symmetrical to the longitudinal and transverse planes of the device are interchanged at the deepest point of the trajectory. Incidentally, the above statement is also valid during the uplift that, although already in disturbed flow, the relative water velocity at its inlet is the same as the direction of the skeletal tangent.

The variability of the angle of the blades relative to the direction of water flow is. the relative displacement of the transmission path and control paths! can be varied so that the optimal blade angle can always be set as a function of the water flow rate and the speed of the blade row or chain.

Displacement of the guide rail 7 corresponding to the transmission path and the control rails 8, 9 of the control tracks relative to each other and to the fixed frame structure (not shown) in a manner known per se, for example by means of a screwing mechanism mounted on the frame structure! can happen. The optimal blade angle can be set according to the respective flow conditions, even during operation.

As a result of the factors below and the structural design of the equipment, e.g. high energy density and low fall height e.g. The large cross-sectional area of the water of rivers with a flow rate of 4.0 to 12.0 km / h can be used, which enables very efficient energy extraction. In natural running water, the equipment can be operated continuously and its operation does not depend on the water level.

The invention is, of course, not limited to the embodiment of the device described in detail above, but can be implemented in several ways within the scope of the claims.

Claims (14)

Claims 1. An apparatus for utilizing the energy of a free winter-colored flowing liquid, in particular running water, having a row of vanes (1) capable of moving and rotating in an endless transmission path fixed to a support structure, a power take-off shaft in rotation with the vanes (1) 3) and a control curve (II la, IIIb) arranged parallel to the transmission path and having a closed curved shape identical to its shape, allowing the blades (1) to rotate through a blade angle adjusting device (13), where the blades (1) are curved surface, the transmission path has a closed curve shape that has - a first forward section (la) obliquely downwards and in relation to the direction of fluid flow (a), - one, that. a second forward section (Ib) extending upwardly and forward from the lower end of the first forward section (Ia); and - a return section (Π) of the second forward section (Ib) extending from the end to the upper end of the first forward section (Ia), and - the position of the control path (Illa, lllb) relative to the transmission path can be changed without interrupting the operation of the device, characterized in that the return section (II) extends above the liquid surface. SZTHH «<00265257 Apparatus according to claim 1, characterized in that the blades (1) have in their central region a slot (1a) opening to one of their longitudinal edges, through which a flexible force transmission means is passed, and inside the slot (1a) attached to the blade (1) in a manner that allows the blade to rotate; and the transmission means has means for converting the forward movement of the transmission means driven by the paddle row formed by the vanes (1) into the rotational movement of the power take-off shaft (3) in the region of the junction of the second forward section (Ib) and the return section (II) of the transmission path. Apparatus according to claim 2, characterized in that the transmission means is a chain (2), the means of which converts the forward movement into a rotating movement of the shaft (3), a sprocket (4) through which the chain (2) is guided. Apparatus according to claim 3, characterized in that the chain (2) is guided by a rigid guide rail (7) with an opening (7a) in the shape of the transmission path, inside which rollers ( 11), the shafts (10b) of which are guided through the chain (2) and are mounted in a blade (1) in such a way as to allow it to rotate. Device according to Claim 4, characterized in that the guide rail (7) is formed by a profile C of metal material. Device according to Claim 4 or 5, characterized in that the width (1) of the gap (1a) of the blade (1) is chosen to exceed the combined width of the chain (2) and the guide rail (7). 7. Figures 1-6. Device according to one of Claims 1 to 4, characterized in that the guide tracks (IIIa, III) have a rigid guide rail (8,9) with an arrow facing the blades (1), preferably a U-profile of metal. Device according to Claim 6 or 7, characterized in that the blade angle adjustment device (13) is connected to a fastening member (12) which grips the outer edge of the blade (1). preferably a rigid spacer member (14) in the form of a triangular plate, having a rod (16) fixed thereon and a slider (15) or roller which is movable in its longitudinal direction, which movably moves into the guide track (IHaJIlb), preferably the guide rail (8, 9) fit. 9. A 2-8. Apparatus according to any one of claims 1 to 4, characterized in that the blades (1) are rectangular, one surface is convex and the other surface is concave, connected to the transmission means, in particular the chain (2), in a longitudinal geometric median plane perpendicular to their side surface. ) and the gap (1a) is formed parallel to their side surface and its height exceeds the half-width (S / 2) of the blade (1). 10. A 2-9. Device according to one of Claims 1 to 4, characterized in that the section of the blades (1) is symmetrical about their transverse central axis (f). Device according to Claim 7 or 8, characterized in that the bearings (5, 6) of the power take-off shaft (3), the guide rail (7) of the transmission device and the control rails (8, 9) of the control tracks (IIIa, IIIb) ) are attached to the support structure. Device according to Claim 11, characterized in that the control rails (8, 9) of the control tracks (IIIa, IIIb) are connected to the support structure in a manner suitable for changing their position relative to the transmission path. 13. Figures 1-12. Apparatus according to any one of claims 1 to 4, characterized in that the support structure is a float. 14. Figures 1-12. Device according to one of Claims 1 to 4, characterized in that it has a support structure in a fixed position, in particular a support frame.