DE20115330U1 - Wind turbine with a casing surrounding the rotor blades - Google Patents

Description

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NEYMEYER & PARTNER GbR, patent attorneys · * 78052«VUlliigen-Se^eiinln5eji (DE) MN / mn 17 September 2001

Applicant ref.: K 263-Gbm

Applicant: KBE Engineering GmbH, Raiffeisenstraße 8

78658 Zimmern o.R·, (DE) Registration number:

Designation: Wind turbine with a rotor blades

surrounding casing

Description

The invention relates to a wind turbine with a rotor provided with rotor blades which drives an electric generator in rotation, wherein the rotor blades are surrounded by a circumferential casing to improve efficiency, the cross-sectional shape of which is aerodynamically similar to the cross-sectional shape of an aircraft wing and the front air inlet cross-section of which is smaller than the rear air outlet cross-section, whereby an increase in the flow velocity of the air flow through the casing is achieved at least in some areas.

Wind turbines of the generic type have been known for decades and are divided into so-called "free-running" wind turbines and so-called ducted turbines. Such ducted turbines of the generic type essentially consist of a rotor which is provided with two or more rotor blades. This rotor

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NEYMEYER& PARTNERGbR, Patent Attorneys » · 78052*'illingen-S< <tnvefinig£eji (DE) MN/mn ..····· September 17, 2001

To generate electrical energy, an electric generator is driven in rotation, with the rotor blades being surrounded by a circumferential casing to improve efficiency.

It has been shown, as can be seen in particular from US 4,132,499, that for certain cross-sectional shapes of the casing, the yield from wind energy can be significantly improved compared to a so-called free-running wind turbine by designing the cross-sectional shape similar to the cross-sectional shape of an aircraft wing. This wing profile is designed as a circumferential ring casing, the front air inlet cross-section of which is smaller than the rear air outlet cross-section. This type of "funnel shape" in conjunction with the aerodynamic cross-sectional shape achieves a significant increase in the flow speed of the air flowing through the casing compared to the environment. WO 00/50769, for example, also deals with the design of different cross-sectional shapes of the casing and an additional diffuser ring arranged in the air outlet area of the casing, in which the different variants of cross-sectional shapes of the casing and different angles of attack of the pre-determined

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NEYMEYER& PARTNERGbR ₁ patent attorneys « * "7»052<Vaiingt!n-SAji^nnin^n(DE) MN / mn * * * September 17, 2001

The cross-sectional profiles for the wind direction are shown.

However, the manufacture of both the casing itself and the diffuser ring additionally arranged on it is problematic, particularly for larger casing turbines whose effective diameter can be several meters. For example, WO 00/55440 proposes producing the casing from individual segments. These segments in turn consist of a tubular space frame, which is covered on the outside with a correspondingly shaped outer surface, for example in the form of individual metal sheets. By joining these individual segments together, a casing with an aerodynamic cross-section and diameters of over 40 meters is produced. Due to the extremely complicated structure, producing such a casing is extremely expensive. The advantage of this design, however, is that the casing itself is extremely stable, so that the rotor, together with a generator driven by this rotor, can be fixed centrally in the casing via a corresponding support structure, without there being any fear that the casing could be damaged due to the high loads, on the one hand due to the weight and on the other hand due to the high wind forces that occur.

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NEYMEYER & PARTNER GbR, patent attorneys ** * 78052 Viüjjj^n-SAwfnninjJen (DE) MN/mn 17 September 2001

In other known casings (US 4,021,135), the casing is made from a solid body into which the rotor is inserted together with the generator as a unit and is held centrally in the casing by means of tension wires. This bracing of the generator in the casing means that the casing must be extremely stable.

As is known, as can be seen from the documents cited, these casings are made of solid material, particularly for smaller casing turbines, and according to current knowledge, they are generally made of a metallic material for stationary casing turbines. This in turn means that extremely high manufacturing costs are involved, particularly in order to achieve an optimal aerodynamic shape of the casing cross-section.

Furthermore, it is known from DE 199 03 846 A1, for example, to manufacture the casing from concrete in order to achieve an extremely high level of stability for this casing. The disadvantage here, however, is that this casing according to this known wind turbine does not have an aerodynamic shape of the casing cross-section, so that a significant improvement in efficiency can only be achieved to a limited extent. On the other hand, a casing turbine with a concrete casing with optimized, ae-

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NEYMEYER & PARTNER GbR, patent attorneys » * 78052*Villiijs£n-SA^;etinigJiji (DE) MN/mn 17 September 2001

A rodynamically shaped casing is extremely difficult to manufacture, as this requires extremely expensive and large molds for casting the casing. In addition, a casing cast from concrete has an extremely high dead weight, so that special measures must be taken for the support or foundation of a column, for example, in order to ensure sufficient stability even at high wind pressures. This also makes such a wind turbine with a concrete casing considerably more expensive, so that it is difficult to imagine its economic use.

Accordingly, the invention is based on the object of equipping a wind turbine of the generic type with a stable, easy to manufacture and thus cost-effective casing.

The object is achieved according to the invention in that the casing is formed from an aerodynamically shaped, surface-coated rigid foam body, or in that the casing is made of plastic and is formed from a peripheral, separate inner wall and a peripheral, separate outer wall, which are connected to one another in their front and rear end regions in the axial direction of the rotor axis, in particular by a welded or adhesive connection, or in that the casing is made from one or more transversely

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NEYMEYER & PARTNER GbR, patent attorneys * * 78052 «VUnngten-SAw^eftnin^eji (DE) MN/mn .···-- September 17, 2001

formed from continuously cast hollow profiles that are aerodynamically shaped and bent all the way around into a circular shape.

The design of the casing according to the invention allows it to be manufactured in a cost-effective manner. Three different embodiments are provided as an alternative.

For example, the casing can be made from an aerodynamically shaped, surface-coated rigid foam body. Such rigid foam bodies have the advantage that they can be precisely machined in a simple manner, so that the profiled cross-sectional shape of the casing is easy to achieve. In order to achieve the most aerodynamically favorable surface possible, the rigid foam body is also coated. Various laminates are used as the coating, which form an extremely precise and smooth surface. Furthermore, this surface coating also significantly increases the inherent stability of the casing, so that it can withstand greater loads, especially during storms or the like.

As a second alternative, the casing can be made of plastic and form a surrounding, separate inner wall and a surrounding, separate outer wall. This means that the casing can be easily made of

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NEYMEYER& PARTNERGBR, patent attorneys »* * ^! 7»)52VillIng%nS«ftw^nnin^n(DE) MN/mn - -- ₁₇ , September 2001

dimensionally stable injection-molded parts can be produced which are connected to one another, for example, in their front and rear end areas in the axial direction of the rotor axis. The connection of these plastic walls can preferably be made by welding and adhesive joints.

As a third variant, the casing is made from one or more continuously cast hollow profiles with an aerodynamic cross-section and bent all the way around into a circular shape. This design makes it particularly easy to produce casings with larger dimensions of up to 20 meters in diameter and corresponding length. Due to the use of hollow profiles, for example aluminum hollow profiles, which can be produced using the continuous casting process, an extremely low weight is achieved with extremely high stability of the entire casing. The cross-section of the continuously cast hollow profiles already corresponds to the wall cross-section of the casing and is bent into a circular shape to form a closed casing ring.

According to claim 2, it can be provided that the casing is divided in the circumferential direction into two or more identically designed individual segments. This

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NEYMEYER & Partner GbR, Patent Attorneys » &diams; MN/mn ~ 17 September 2001

has the advantage, particularly in the manufacture of larger casings, that the individual components are smaller and thus take up less space, particularly for transport, and are also lighter themselves. This division into two or more individual segments is provided for all three design variants of the casing according to claim 1.

Furthermore, according to claim 3, for the second alternative of the design of the plastic casing, it can be provided that the inner wall and the outer wall of the casing form a single or multi-part cavity which is filled with a hardening rigid foam. This additional foaming of the cavity between the inner wall and the outer wall also results in considerable stiffening of the entire casing, so that the plastic variant also has an extremely high inherent stability and is therefore also suitable for greater loads and for larger dimensions.

In a further advantageous embodiment, according to claim 4, it can be provided that the casing is divided in the axial direction of the axis of rotation of the rotor into two or more continuous cast hollow profiles lying one behind the other and connected to one another to form a housing body.

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NEYMEYER& PARTNERGbR, patent attorneys »^ , _# .* ~ ⁷⁸ °5?^UUij^SAfti^ MN /mn "" 17 September 2001

This subdivision also makes it easier to transport larger casings. The individual continuous cast hollow profiles, which are arranged one behind the other and connected to one another, form a section of the aerodynamic cross-sectional shape in the area of their respective axial length. This means that the axial continuous cast hollow profiles are designed like boxes and, in their assembled structure, form the finished cross-sectional shape of the entire casing.

Furthermore, according to claim 5, particularly for larger casings, it can be provided that only one front and one rear continuous cast hollow profile are provided, the shape of which corresponds to the cross-sectional shape of the casing in the corresponding axial areas. Between these continuous cast hollow profiles, which are spaced apart from one another in the axial direction, inner and outer guide plates are provided to achieve the remaining cross-sectional shape, by means of which the continuous cast hollow profiles are fixedly connected to one another. These guide plates form the inner wall and the outer wall of the casing in the corresponding axial area. It goes without saying that the guide plates are also bent in the circumferential direction and also have a correspondingly bent profile in the axial direction, so that the guide plates together with the continuous cast hollow profiles form the aerodynamic cross-sectional shape of the casing.

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NEYMEYER & PARTNER GbR, Patent Attorneys » ^ ₄₄ " MN/mn " 17 September 2001

According to claim 6, it can be provided that, particularly with a greater axial length of the casing and thus with a greater axial distance between the two continuously cast hollow profiles according to claim 5, stiffening webs are introduced between the inner and outer guide plates. This makes it possible to achieve an extremely high inherent rigidity of the casing and, on the other hand, a precise cross-sectional shape.

In order to subject the casing designed according to the invention to as little external load as possible, according to claim 7, the rotor is mounted together with the generator on a column-like support device that projects radially through the casing and can be mounted in a fixed position on a base. It is also provided that the casing is supported by a separate support device. This support device can be attached either to the base, to the support device of the rotor or to the generator. The invention also provides for attachment, for example by means of corresponding support struts of the casing directly to the generator. Due to this self-supporting mounting of the casing, no additional loads are transferred to the casing, for example due to the dead weight of the rotor together with the generator or the wind pressure acting on the rotor.

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NEYMEYER & PARTNER GbR, Patent Attorneys MN/mn

17 September 2001

The coupling of the separate support device of the casing and the separate support device of the rotor or generator is designed in such a way that, according to claim 8, the rotor, the generator and the casing are jointly mounted so that they can rotate about an essentially vertical axis of rotation running at right angles to the rotor axis. A rotationally fixed connection of the support device and the support device is provided so that when the entire wind turbine is aligned depending on the wind direction, the rotor with the generator together with the casing are aligned together with this corresponding wind direction.

To further improve the efficiency, according to claim 9, at least one diffuser ring with a larger diameter is provided in the area of the air outlet on the casing, which is conically widened in the direction of the air flow. Towards the casing, an essentially completely circumferential air gap is formed between the diffuser ring and the casing, which, in conjunction with the radially outward deflection of the air flow, causes an additional increase in the flow speed of the air flow passed through the casing. This diffuser ring thus further improves the efficiency of the wind turbine according to the invention.

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NEYMEYER & PARTiNER GBR, patent attorneys MN / mn

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17 September 2001

Depending on the size and design of the casing, several diffuser rings with increasing diameters can also be provided in the area of the air outlet on the casing according to claim 10. These are arranged one behind the other in the direction of flow and also form an essentially completely circumferential air gap between them. This design also further improves the efficiency of the wind turbine.

The fact that the air gaps provided according to claims 9 and 10 are to run "essentially" all the way around means that they are to be interrupted only by corresponding retaining webs between the rings or the first diffuser ring on the casing in order to optimize the effect of the additionally introduced and radially outwardly deflected air flow as much as possible.

An embodiment of the wind turbine according to the invention and different variants of the design of the casing are shown below with the aid of the drawing. The invention is not limited to the specific embodiment or designs of the casing, but also includes other variants not specifically described as embodiments, which are the subject of the patent claims. It shows:

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NEYME YER & PARTNER GbR, patent attorneys MN/mn

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Fig. 1 is a perspective view of a wind turbine of the type according to the invention;

Fig. 2 is a vertical section through the wind turbine of Fig. l;

Fig. 3 shows the pivot bearing of the wind turbine from Figs. 1 and 2 as an enlarged section III from Fig. 2;

Fig. 4 a cross-section through the casing of the wind turbine consisting of a surface-coated rigid foam body;

Fig. 5 a cross-section through the casing made of plastic with a surrounding, separate inner and outer wall;

Fig. 6 a cross section through the casing, which consists of a front and rear continuous casting

hollow profile, which are connected to each other via an inner and an outer guide plate,-

Fig. 7 the embodiment of the housing cross-section according to Fig. 5 with additional stiffening

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NeymeYER & PARTNER GbR, patent attorneys · _e * 7»052Vill|n^fen-S MN/mn * 17 September 2001

Fig. 8 shows a casing divided in axial direction into several continuous cast profiles in cross section;

Fig. 9 shows a cross-section of a casing made in one piece as an extruded profile.

Fig. 1 shows a perspective view of a wind turbine 1 according to the invention with a casing 2, a rotor 3, a generator 4 and a diffuser ring 5 arranged at the rear end of the casing 2. In the present embodiment, the rotor 3 is provided with five rotor blades 6, by means of which the rotor is driven in rotation when an appropriate air flow flows through the casing 2. This rotational movement of the rotor 3 is transmitted via a corresponding mechanical coupling to the generator 4 (not shown in detail in the drawing), so that the generator generates electrical energy.

The casing 2 has an aerodynamic shape, the cross-sectional shape of which is similar to the shape of the wing of an aircraft, as can be seen in particular from Fig. 2. As can be seen from Figs. 1 and 2, the rotor 3 together with the generator 4 is arranged on a column-like support device 7 that can be mounted in a fixed position on the ground. To mount the rotor 3 together with the generator 4 on the support device,

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Neymeyer & PARTNER GbR, patent attorneys? . ,· » « * 780.5Wi]]jij^fen-SA|jVpnnin^n (DE) MN / mn 17 September 2001

device 7, a type of cross slide 8 is provided, which in the present embodiment is fixedly mounted on the support device 7 with a vertically downward-directed mounting cylinder 9.

In the present embodiment, the cross slide 8 consists of a lower support plate 10 on which a second bearing plate II is provided, which is adjustably mounted with the support plate 10 via a dovetail connection 12 (Fig. 2) in the horizontal direction transverse to the axis of rotation 13 of the rotor 3. Furthermore, a mounting plate 14 is provided on this bearing plate II, on which the generator 4 is fixedly mounted. This mounting plate 14 is in turn connected to the middle bearing plate II in the axial direction of the axis of rotation 13 via a dovetail connection 15 running transversely to the dovetail connection 12. By means of these two dovetail connections 12 and 15, the generator 4 and thus also the rotor 3 can be aligned centrally with respect to the casing 2 on the one hand and an optimal axial position of the rotor 3 with its rotor blades 6 can be set as far as possible in the narrowest cross-sectional area of the air passage of the casing 2.

Furthermore, the support plate 10 and the bearing plate 11 have an extension section 16 and 17 respectively on the rear side.

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NEYMEYER & PARTNER GbR, patent attorneys *-«·#»* 7*Q5WiI}jnj(lSÄ MN / mn 17 September 2001

which is provided for supporting a bearing module 18 for a total of four closing flaps 19 arranged in the rear end area of the outflow area of the casing 2. Furthermore, this bearing module 18 has an actuator, which is shown in simplified form in particular in Figs. 1 and 2 as an actuating shaft 20 and in the present embodiment is used for exact axial positioning in the direction of the axis of rotation 13 of the rotor 3 for the generator 4 together with the rotor 3.

Such an axial position should be selected in such a way that the rotor in the operating state with its rotor blades 6 is arranged essentially in the area of the narrowest inner point of the casing 2. Such an axial adjustment can also be carried out manually by simply turning the adjusting shaft 20, which can be locked when the optimal axial position of the rotor blades 6 is reached. The same applies to the dovetail connection 12, which can also be adjusted and fixed in its horizontal transverse position to the support plate 10 using corresponding adjusting spindles. Furthermore, a corresponding height adjustment of the entire arrangement, consisting of rotor 3, generator 4, mounting plate 14, bearing plate II and support plate 10, is also provided, which can be provided in the area of the mounting cylinder 9 and has a corresponding vertical, relative

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ve adjustment of the axis of rotation 13 for its concentric alignment with respect to the casing 2.

As can also be seen from Fig. 1 and 2, the casing 2 can be connected to the substrate in a self-supporting manner via a separate support device S 21.

As can be seen in particular from Fig. 3, this support device 21 is a component of the casing. The support device 7 of the rotor 3 and the generator 4 extends through both the casing 2 and the support device 21 of the casing 2. In the present exemplary embodiment, the support device 7 and the support device 21 are essentially cylindrical and are each provided with a lower mounting flange 22 and 23, respectively. Via these two mounting flanges 22 and 23, the support device 7 and the support device 21 are mounted together on a rotatable bearing ring 24, which in turn is rotatably received on a bearing plate 25.

The bearing ring 24 and the bearing plate 25 together form a rolling bearing, wherein the bearing plate 25 can be fixedly mounted on a base, such as a support column (not shown in detail in the drawing), for the final assembly of the entire wind turbine.

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NEYMEYER& PARTNER GbR, patent attorneys · i * · · 78052 Viyin|en^ckwenningen (DE) MN/mn ·· "" September 17, 2001

By jointly mounting the support device 7 with its mounting flange 22 and the support device 21 with its mounting flange 23 on the bearing ring 24 and their concentric arrangement with respect to the vertical axis of rotation 26 of the rolling bearing consisting of the bearing ring 24 and the bearing plate 25, a joint pivoting movement of the mounting housing 2 and the rotor 3 together with the generator 4 is achieved. By this rotatable mounting of the casing 2 together with the rotor 3 and the generator 4, the entire wind turbine 1 automatically aligns itself to the prevailing wind direction.

This is shown by way of example in Fig. 1 and 2 by arrows 27 and 28. It can be seen that such an alignment is carried out in such a way that the air flow enters the casing 2 in the area of the rotor blades 6, i.e. at the front, and exits the casing 2 again at the rear in the area of the diffuser ring 5. Due to the "conical" profiled expanded shape in the flow direction of the arrows 2 7 and 2 8 and the aerodynamic shape of the casing 2, as can be seen in particular from Fig. 2, a considerable acceleration of the flow velocity within the casing 2, in particular in the axial area of the rotor blades 6, is achieved, so that the efficiency of utilizing wind energy is significantly increased.

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NEYMEYER & Partner GbR, Patent Attorneys MN/mn ······· * September 17, 2001

As can already be seen from Fig. 1 and 2, the casing 2 has an inner wall 34 and an outer wall 35 in cross section. Different structures are provided for the casing 2, which are explained in more detail in Fig. 4 to 9 described below.

As can also be seen from Fig. 1 and 2, the diffuser ring 5 has a larger diameter than the rear end region of the casing 2. Several radial webs 29 are used to mount the diffuser ring 5, which are embedded, for example, in the rear end region of the casing 2. These radial webs 29 can be an integral part of the diffuser ring 5 or an integral part of the casing 2. A separate design of these radial webs 29 is also provided, whereby screw, adhesive or other suitable connections can be provided between the radial webs 29 and the casing 2 on the one hand and the radial webs 29 and the diffuser ring 5 on the other.

As can be seen in particular from Fig. 2, the diffuser ring 5 is also designed to be conically widened in the flow direction of the arrows 28, so that this increases the acceleration effect of the air flow. Another decisive factor for this effect is that the diffuser ring 5 is mounted on the

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NEYMEYER& PARTNER GBR, patent attorneys « J * i · 78052 fiJlingemSchwenningen (DE) MN/mn ....····* September 17, 2001

entire circumference and thus an essentially completely circumferential annular gap 3 0 is formed. A flow of air (arrow 31) flowing along the outer surface of the casing 2 flows through this annular gap 3 0 and is also deflected radially outwards again by the conical, also aerodynamically designed cross-sectional shape of the diffuser ring 5, as is already known from the prior art, which in turn increases the suction effect at the end of the casing 2. This in turn leads to an acceleration of the air flow within the casing 2, in particular in the area of the rotor blades 6. To further increase the flow speed, further diffuser rings can be provided, which in turn are radially larger than the diffuser ring 5 shown in Figs. 1 and 2, so that a further flow amplification can be achieved.

Fig. 4 shows a cross-sectional structure of a jacket housing 2/1, as can be used in particular for jacket housings of smaller diameters, for example from 1.5 to 5 m. Such a structure is, however, not limited to this diameter size of the jacket housing 2/1.

According to the embodiment of Fig. 3, it is provided that the casing 2/1 is formed from an aerodynamically shaped, surface-coated hard foam body 32.

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NEYMEYER & PARTNER GbR, patent attorneys · J * &iacgr; * 78052 tjJ]jngei»S*wenningen (DE) MN/mn ** 17 September 2001

This hard foam body 32 can be machined in a very simple manner so that a precise cross-sectional shape, as shown by way of example in Fig. 3, can be achieved extremely cost-effectively. To improve the mechanical properties, in particular the inherent stability, of a casing 2 designed as a hard foam body 32, a surface coating 33 is provided which surrounds the entire surface of the hard foam body 32. This coating, which can be designed as a GRP laminate, for example, significantly improves the stability of the hard foam body 32 in terms of its rigidity and also dimensional stability. Furthermore, such laminates are extremely easy to machine so that an extremely smooth, aerodynamic surface structure can be achieved. It can be seen that in this embodiment of Fig. 4 the diffuser ring 5/1 is also formed from a coated hard foam body. The radial web shown in simplified form can also be made from such a material, which results in an extremely low overall weight of the casing 2/1.

As an alternative to this design of the casing, it can also be made of plastic, as shown in Fig. 5. It is provided that the casing 2/2 consists of a separate inner wall 36 and a separate outer wall 37. This inner wall 36 and this outer

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Neymeyer & PARTNER GbR, Patent Attorneys MN/mn 17 September 2001

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wall 3 7 can be manufactured as an injection-molded part, whereby an extremely high precision of the cross-sectional shape of the casing 2/2 can be achieved. In the front end area 3 8 and in the rear end area 39, an adhesive connection or a plastic welded connection can be provided to connect the inner wall 36 and the outer wall.

The inner wall 36 and the outer wall 37 thus form a closed, circumferential cavity 40, which can also be filled with foam to further stabilize the casing 2/2. As can also be seen from Fig. 5, the diffuser ring 5/2 can be manufactured in the same way and also consist of plastic and have a separate inner wall 41 and a separate outer wall 42, which can also be glued or welded in their contact areas. In the case of the diffuser ring 5/2, its cavity 34 can also be filled with foam, which increases the stability of the diffuser ring 5/2.

These two embodiments of the casing 2/1 and 2/2 according to the embodiments in Fig. 4 and 5 have in common that they are characterized by extremely high dimensional stability and extremely low weight. This in turn means that no heavy foundations or the like are used.

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NEYMEYER & PARTNER GbR, patent attorneys · i » · _# 7,8052 ViJUngere-Srfiwenningen (DE) MN/mn 17 September 2001

in order to be able to anchor a wind turbine of the type according to the invention to the ground. In particular, in comparison to a free-running wind turbine, the total weight is only slightly higher for the same effective diameter of the rotor, i.e. for the same size.

Fig. 6 shows a further embodiment of the cross-sectional shape of a casing 2/3, in which the front end region 45 and the rear end region 46 of the casing 2/3 are formed from a prefabricated continuously cast hollow profile 47 or 48. The two continuously cast hollow profiles 47 and 48 form part of the desired cross-sectional shape of the casing 2/3 in the respective axial front end region 45 and rear end region 46. As can also be seen from Fig. 6, these two continuously cast hollow profiles 47 and 48 have a relatively large axial distance from one another, which in the embodiment according to Fig. 6 are connected to one another by correspondingly curved guide plates 49 and 50 which form the remainder of the aerodynamic cross-sectional shape of the casing 2/3.

These guide plates 49 and 50 have a slightly curved shape in their respective axial areas, so that the entire aerodynamic cross-sectional shape of the casing 2/3 is determined by the common surface

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NEYMEYER & PARTNERGBK, Patent Attorneys _% · J · · , J90S2 ^UüngemS^iwenningen (DE)

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forming continuous cast hollow profiles 47 and 48 and the two guide plates 49 and 50. In the present embodiment of Fig. 6, the guide plate 49 forms the inner wall of the casing 2/3, while the guide plate 50 forms the outer wall of this casing 2/3. To increase stability, particularly in the area of the guide plates 49 and 50, the cavity 51 formed between them can also be filled with foam.

As an alternative to this foaming, between the

10' guide plates 49 and 50, corresponding support struts 52, 53 and 54 can also be provided, as is shown for the embodiment of the jacket housing 2/4 in Fig. 7. The front and rear end regions 55 and 56 of the jacket housing 2/4 are in this case again designed as continuously cast hollow profiles 57 and 58, respectively, the shape of which in the present embodiment corresponds to the shape of the two continuously cast hollow profiles 47 and 48 of the embodiment according to Fig. 6. The two guide plates 59 and 60 of the casing 2/4 also correspond to the guide plates 49 and 50 of the embodiment of the casing 2/3 according to Fig. 6. In both embodiments of the casing 2/3 and 2/4, the continuously cast hollow profiles 47 and 48 or 57 and 58 are bent in the circumferential direction to form a circumferential circular ring and are welded or glued, for example, in the region of their butt-jointed ends.

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NEYMEYER & Partner GbR, Patent Attorneys _§ · J · · _# ^«0S2 ViUingeit-Schwenningen (DE) MN/mn ...···· September 17, 2001

It can also be provided that the jacket housing 2/1, 2/2, 2/3 and 2/4 is divided in the circumferential direction into several identically designed segments, which are connected to one another by adhesive, welding or other suitable connections and form the respective complete jacket housing 2/1, 2/2, 2/3 or 2/4.

Fig. 8 shows a further alternative 2/5 for the design of a casing. In this case, it is provided that a continuous cast hollow profile 64 or 65 with a corresponding cross-sectional shape is also provided in the front end region 62 and in the rear end region 63. Instead of the two inner and outer guide plates 50 and 59 and 60 according to the embodiments according to Figs. 6 and 7, the axial space between the axially spaced continuous cast hollow profiles 64 and 65 is designed with three further continuous cast hollow profiles 66, 67 and 68. These continuous cast hollow profiles 66, 67, 68 can be axially inserted into one another and glued or screwed together, for example, as can be seen in Fig. 8. Thus, a uniform casing 2/5 is formed from these continuously cast hollow profiles 64 to 66, the cross-sectional shape of which is identical to the previously described embodiments according to Figs. 4 to 7.

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NEYMEYER& PARTNER GbR, patent attorneys _t * S * · · _# .'Ä052 ViUingeft-&euro;ehwenningen (DE) MN/mn .··&diams;··· _{17 Sep} te _m ber2001

Fig. 9 shows a further variant 2/6 of a casing, in which its cross-sectional shape is formed by a single, uniform continuous-cast hollow profile 70. This continuous-cast hollow profile 70 forms a corresponding inner wall 71 and a corresponding outer wall 72, the shape of which also corresponds to the shape of the cross-sectional shape of the previous embodiments according to Figs. 4 to 8. This continuous-cast hollow profile 70 with its inner and outer walls 70, 72 is reinforced in the present embodiment by two circumferential radial walls 73 and 74, respectively.

The design of the casing 2/5 is also characterized by an extremely lightweight and cost-effective construction. The design variants with the continuously cast hollow profiles are particularly suitable for larger casings, as they are characterized by a high level of inherent rigidity, which means that they can reliably withstand the wind forces and pressures that occur. Furthermore, extremely high contour accuracy can be achieved by using continuously cast hollow profiles. After the continuous casting process, these continuously cast hollow profiles, which already have the corresponding cross-sectional shape, as shown in the drawing as an example, are bent with the corresponding radius so that they form a complete ring casing after the entire casing has been completed.

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NEYMEYER & Partner GbR, patent attorneys ₄ « years. · _## 7*052 ViUingeiHSchwenningen (DE)

₄ MN/mn."····· September 17, 2001

These casings or continuously cast hollow profiles can also form only partial segments of the entire casing in the circumferential direction and can be firmly connected to one another in the area of their ring joint in a suitable manner, for example by welding, gluing or screwing. The mounting of such casings made from continuously cast hollow profiles takes place in an equivalent manner to the connecting elements described in Fig. 1 and 2 or Fig. 3.

It is understood that in this case the support device 21 is not designed as a one-piece component of one of these continuous cast hollow profiles, but is attached as a separate support cylinder to the underside of the corresponding casing. The known types of connection are also provided for this. A circumferential ring flange can be provided on the support device, which can be arranged, for example, sunk into a corresponding depression in the outer contour of the casing.

Thus, the design according to the invention with all its alternatives provides a casing for wind turbines which has an extremely low dead weight, is easy and inexpensive to manufacture and also has an extremely high quality of cross-sectional shape while at the same time being very stable. In particular, the type of assembly of a

K263-Gbm.doc

NEYMEYER & PARTNER GbR, patent attorneys · * * · · _m ^052 VjUingen-HSthwenningen (DE) MN/mn .*»*··· September 17, 2001

Such a casing can be carried out easily and safely due to the separate support device.

As an alternative to the support device 21 shown in Fig. 1 and 2, a bracing from the inner wall 34 (Fig. 2) to the generator 4 or also to the support device 7 can be provided in order to achieve a precisely aligned assembly of the casing 2 or one of its variants relative to the rotor 3 with its rotor blades 6.

K263-Gbm.doc

Claims (10)

1. Wind power turbine ( 1 ) with a rotor ( 3 ) provided with rotor blades (6) which drives an electric generator ( 4 ) in rotation, the rotor blades ( 6 ) being surrounded by a circumferential casing ( 2 , 2/1 , 2/2 , 2/3 , 2/4 , 2/5 , 2/6 ) to improve efficiency, the cross-sectional shape of which is aerodynamically similar to the cross- sectional shape of an aircraft wing and the front air inlet cross-section (arrows 27 ) of which is smaller than the rear air outlet cross-section (arrows 28 ), whereby at least in some areas an increase in the flow velocity of the air flowing through the casing ( 2 , 2/1 , 2/2 , 2/3 , 2/4 , 2/5 , 2/6 ) is achieved . air flow is achieved, characterized in that
that the casing ( 2 , 2 / 1 ) is formed from an aerodynamically shaped, surface-coated hard foam body ( 32 ), or
that the casing ( 2/2 ) consists of plastic and is formed from a circumferential, separate inner wall ( 36 ) and a circumferential, separate outer wall ( 37 ), which are connected to one another in their front and rear end regions ( 38 , 39 ) in the axial direction of the rotor axis ( 13 ), in particular by a welded or adhesive connection, or
that the casing ( 2/3 , 2/4 , 2/5 , 2/6 ) is formed from one or more continuously cast hollow profiles ( 70 ) or continuously cast hollow profiles ( 47 , 48 , 57 , 58 , 64 , 65 , 66 , 67 , 68 ) which are aerodynamically shaped in cross-section and bent all the way around into a circular shape. 2. Wind power turbine ( 1 ) according to claim 1, characterized in that the casing ( 2 , 2/1 , 2/2 , 2/3 , 2/4 , 2/5 , 2/6 ) is divided in the circumferential direction into two or more identically designed individual segments. 3. Wind power turbine ( 1 ) according to claim 1 or 2, characterized in that the inner wall ( 36 , 49 ) and the outer wall ( 37 , 50 ) of the casing ( 2/2 , 2/3 ) form a one-part or multi-part cavity ( 40 , 51 ) which is filled with a hardening rigid foam. 4. Wind power turbine ( 1 ) according to claim 1 or 2, characterized in that the casing ( 2/5 ) is divided in the axial direction of the axis of rotation (13) of the rotor (3 ) into two or more continuously cast hollow profiles ( 64 , 65 , 66 , 67 , 68 ) lying one behind the other and connected to one another to form a casing body, and that the continuously cast hollow profiles ( 64 , 65 , 66 , 67 , 68 ) form a partial section of the aerodynamic cross-sectional shape of the casing ( 2/5 ) over their respective axial length. 5. Wind power turbine ( 1 ) according to claim 4, characterized in that the front and rear continuously cast hollow profile or the front and rear continuously cast hollow profiles ( 47 , 57 and 48 , 58 ) are spaced apart from one another in the axial direction and are fixedly connected to one another via inner and outer guide plates ( 49 , 59 and 50 , 60 ) forming the inner wall and the outer wall, and that the guide plates ( 49 , 50 , 59 , 60 ) together with the continuously cast hollow profiles ( 47 , 48 , 57 , 58 ) form the aerodynamic cross-sectional shape of the casing ( 2/3 , 2/4 ) . 6. Wind power turbine ( 1 ) according to claim 5, characterized in that, particularly in the case of a larger axial distance between the continuously cast hollow profiles ( 57 , 58 ) from one another, support struts ( 52 , 53 , 54 ) are provided between the inner guide plates ( 59 ) and the outer guide plates ( 6 ). 7. Wind power turbine ( 1 ) according to one of claims 1 to 6, characterized in that the rotor ( 3 ) together with the generator ( 4 ) is mounted on a column-like support device ( 7 ) which projects radially through the casing ( 2 ) and can be mounted in a fixed manner on a base, and that the casing ( 2 ) is fastened to the base, to the support device ( 7 ) or to the generator ( 4 ) via a separate support device ( 21 ). 8. Wind power turbine ( 1 ) according to claim 7, characterized in that the rotor ( 3 ), the generator ( 4 ) and the casing ( 2 ) are jointly mounted for rotation about a substantially vertical axis of rotation ( 26 ) running at right angles to the rotor axis ( 13 ) and are connected to one another in a rotationally fixed manner. 9. Wind power turbine ( 1 ) according to one of claims 1 to 8, characterized in that in the region of the air outlet (arrows 28 ) on the casing ( 2 ) at least one diffuser ring ( 5 ) of larger diameter is provided, which is conically widened in the direction of the air flow (arrows 27 , 28 ) and forms an essentially completely circumferential air gap ( 30 ) towards the casing ( 2 ). 10. Wind turbine according to claim 9, characterized in that in the region of the air outlet on the casing several diffuser rings with increasing diameter are provided, which are arranged one behind the other in the direction of flow and form between them a substantially completely circumferential air gap.