A wind blade and hub connection system

Abstract

A wind blade and hub connection system, wherein the wind blade includes a blade stem; a stay rope is provided between the blade stem and the hub and / or between the blade stem and a main shaft provided on the hub, and the stay rope is in a tensioned state. On the one hand, the present invention can not only reduce the centrifugal force and torsion generated by the rotation of the blade, but also improve the anti-fatigue performance of the impeller and has a certain degree of light weight; on the other hand, it can ensure that the stay rope is not easily broken. Moreover, by combining with a loop rope, on the premise of ensuring the balanced force of each blade stem, the anti-torsion and anti-centrifugal force performance of the wind wheel can be further ensured, and the stay rope is not easily loosened.

Description

Technical Field

[0001] The present invention relates to a wind turbine, in particular to a connection system between a wind blade and a hub. Background Art

[0002] A wind turbine mainly includes a tower, a generator, a hub and an impeller, where the impeller includes multiple wind blades. When the existing wind wheel rotates too fast, a large centrifugal force will be generated. The existing way to solve the centrifugal force is to make the structure of the blade thicker, such as increasing the thickness of the blade housing and the rods or plates of the internal skeleton. However, this way will increase the weight of the wind wheel, and when the wind wheel becomes heavier, the tower also needs to be redesigned to increase its weight, which in turn makes the entire wind turbine very heavy and cannot achieve lightweight. Moreover, the existing wind blades will generate fatigue during the 360° rotation process because they will be subjected to both tensile and compressive forces during rotation. Once fatigued, the structural strength will be greatly reduced.

[0003] Therefore, the present invention urgently needs to design a structure that can solve the technical problems of the centrifugal force and fatigue of the wind wheel. Summary of the Invention

[0004] The purpose of the present invention is to overcome the above deficiencies of the prior art and provide a connection system between a wind blade and a hub with strong anti - centrifugal force, anti - torsion force and anti - fatigue ability.

[0005] The technical solution of the present invention is: a connection system between a wind blade and a hub, the wind blade includes a blade stem; an inclined stay rope is provided between the blade stem and the hub and / or between the blade stem and a main shaft provided on the hub, and the inclined stay rope is in a tensioned state.

[0006] Further, one end of the inclined stay rope is connected to the inner side of the blade stem, and the other end is connected to the edge side of the hub.

[0007] Further, the main shaft is fixed inside the hub, a connection part is provided on the main shaft, and the inclined stay rope is connected to the connection part of the main shaft.

[0008] Further, at least two cross - arranged inclined stay ropes are provided between the blade stem and the hub; or at least two inclined stay ropes that are inclined towards each other and do not cross are provided between the blade stem and the main shaft inside the hub.

[0009] Further, the connection points of the inclined stay rope with the blade stem and the hub are arranged diagonally, one connection point is arranged on the inner side of the blade stem, and the other connection point is arranged on one side of the surface where the hub is connected to the blade stem.

[0010] Further, the hub is a polyhedron structure, a column is provided between two adjacent surfaces connecting the blade stem, and the inclined stay rope is connected to the column; or a flange is provided on the main shaft, and the flange extends along the hub, and the inclined stay rope is connected to the flange.

[0011] Furthermore, a C-shaped seat is provided at the connection point of the hub, which can connect stay ropes to the leaf stems on both adjacent sides simultaneously.

[0012] Furthermore, the leaf stem is of a truss structure, and at least one stay rope seat for connecting stay ropes is provided on the rod body of the truss, and the stay rope seat is inclined.

[0013] Furthermore, the wind blade further includes a blade body, the leaf stem is arranged inside the blade body, and one end extends along the blade body to be connected to the hub, and the stay rope is connected to the extended section of the leaf stem.

[0014] Furthermore, the stay rope seat is a double-rope seat. One stay rope seat in the double-rope seat is arranged on the inner side of the leaf stem, and the other stay rope seat is arranged on the outer side of the leaf stem, and the two are symmetrically arranged; and a loop rope is connected between the outer sides of adjacent leaf stems, and the loop rope is connected to the stay rope seat on the outer side of the leaf stem.

[0015] Furthermore, the tension of the loop rope is greater than that of the stay rope.

[0016] The beneficial effects of the present invention are as follows: on the one hand, it can not only reduce the centrifugal force and torsion generated by the rotation of the blade, but also improve the anti-fatigue performance of the impeller and have a certain degree of lightweight; on the other hand, it can ensure that the stay rope is not easily broken. Moreover, by combining the loop rope, it can further ensure the anti-torsion and anti-centrifugal force performance of the wind wheel on the premise of ensuring the balanced force of each leaf stem, and it is not easy to make the stay rope slack. BRIEF DESCRIPTION OF THE DRAWINGS

[0017] Figure 1 is a schematic structural diagram of Embodiment 1 of the present invention;

[0018] Figure 2 is a schematic structural diagram of Embodiment 2 and Embodiment 3 of the present invention.

[0019] DESCRIPTION OF THE REFERENCE NUMERALS:

[0020] 1. Wind blade; 2. Hub; 3. Stay rope; 4. Hub rope seat; 5. C-shaped seat; 6. Loop rope; 7. Loop rope seat; 8. Main shaft; 9. Shaft rope seat; 11. Leaf stem; 12. Blade body; 21. Cylinder; 81. Flange; 111. Longitudinal rod; 112. Cross bar; 113. Support rod. DETAILED DESCRIPTION OF THE INVENTION

[0021] The following will further describe the present invention in detail with reference to the accompanying drawings of the specification and specific embodiments.

[0022] Embodiment 1

[0023] As Figure 1As shown: A wind blade and hub connection system, wherein the wind blade 1 includes a blade stem 11; a stay rope 3 is provided between the blade stem 11 and the hub 2, and the stay rope is in a tensioned state.

[0024] The above solution has the following advantages: (1) By setting a stay rope between the blade stem and the hub and making it stay-cabled, its anti-centrifugal force and anti-torsion performance can be enhanced. Since it can withstand the centrifugal force, the key is the tensile strength of the wind blade. And the stay rope resists tension but not compression, so it can transfer the centrifugal force received by the wind blade to the stay rope. Moreover, the stay rope is light in weight and will not increase the weight of the wind wheel, greatly saving materials and improving the lightweight of the wind wheel. In addition, since the wind blade will generate fatigue during the 360° rotation process, because the wind blade is subjected to two kinds of forces, tension and pressure, fatigue is generated only under two-way stress, and no fatigue is generated under one-way stress. And the stay rope is under one-way stress, so the fatigue effect of the wind blade can be eliminated. It can be said that the present invention sets the stay rope, which can not only reduce the centrifugal force and torsion generated by the rotation of the wind blade, but also improve the anti-fatigue performance of the impeller and has a high lightweight level. (2) Although the blade stem itself has a certain stiffness, when the impeller rotates too fast, its stiffness still cannot resist the centrifugal force. By setting a stay-cabled stay rope between the blade stem and the hub and the stay rope is in a tensioned state, the tensile strength can be improved, and it cannot be directly pulled, because direct pulling cannot achieve the effect of resisting the centrifugal force; the tension degree of the stay cable should be such that it can resist the centrifugal force and will not damage the stiffness of the blade stem.

[0025] In this embodiment, the stay rope 3 can be a steel wire rope, or other metal ropes, or non-metal ropes such as carbon fiber ropes.

[0026] In this embodiment, the wind blade 1 includes a blade stem 11 and a blade body 12. The blade stem 11 is disposed inside the blade body 12, and one end extends along the blade body and is connected to the hub 2 through a flange. The stay rope 3 is connected to the extended section of the blade stem and is connected to the inner end away from the hub 2. That is, a hub rope seat 4 for connecting the stay rope is provided on the side of the blade stem 11 close to the blade body. A sealing plate is provided at the end where the blade stem 11 extends out of the blade body 12 to seal the inner cavity of the blade body. The blade stem 11 is preferably designed in a quadrilateral structure, including four longitudinal rods 111 and cross bars 112 connected between the longitudinal rods. A number of support rods 113 are also provided between the longitudinal rods. When the four longitudinal rods 111 of the blade stem 11 are connected to the hub 2 through a flange, hub rope seats 4 can be respectively arranged inside the four longitudinal rods 111, and then four stay ropes 3 are connected to the blade stem. The reason for connecting the stay rope 3 to the inner side of the blade stem in this embodiment, that is, to the inner side of the longitudinal rod of the blade stem, is that the torsional resistance of the inner side is worse than that of the outer side, and it bears the combined action of all the centrifugal forces on the outer side. Therefore, the torsional resistance and the resistance to centrifugal force of the wind wheel can be greatly improved in this embodiment. In this embodiment, the stay rope is preferably connected to the root position of the blade stem. On the one hand, the longer the stay rope, the greater the pressure it bears, and it is easy to break the wire or even break as a whole. Moreover, the force at the root is relatively uniform, and it is not easy to make the stay rope slack. On the other hand, it is convenient to set the hub rope seat. If the stay rope is connected to the blade stem extending into the cavity of the blade body, it is not easy to set the hub rope seat, which will lead to a more complex structure.

[0027] In this embodiment, the two stay ropes 3 on the adjacent longitudinal rods of the blade stem are arranged in a cross shape to form an X-shaped structure to further improve the torsional resistance and the resistance to centrifugal force. When four stay ropes 3 are connected to the blade stem, the four stay ropes cross each other in pairs, that is, the two stay ropes on the windward side of the blade stem cross each other, and the two stay ropes on the leeward side of the blade stem cross each other.

[0028] In this embodiment, the hub 2 is a polyhedron structure. A column 21 is provided between two adjacent faces connecting the blade stem. A C-shaped seat 5 for connecting the stay rope is provided on the column 21. Specifically, the hub 2 is designed according to the number of wind blades. For example, the wind wheel in this embodiment includes three wind blades 1, then the hub 2 is preferably designed in a triangular prism structure. The wind blades arranged on the three faces of the triangular prism are symmetrically distributed, and the C-shaped seats 5 arranged on the three columns are also symmetrically distributed. The blade stem 11 is connected to the hub through a flange. The hub rope seat 4 on the blade stem and the C-shaped seat 5 on the hub 2 are arranged diagonally, so that the stay rope 3 connected between the two is in a tilted state and is tightened.

[0029] The reason for designing the C-shaped seat 5 in this embodiment is that it can connect the stay ropes with the blade stems on the adjacent two sides at the same time, that is, one C-shaped seat connects two stay ropes, which not only simplifies the structure but also ensures the force balance of the C-shaped seat.

[0030] In this embodiment, the hub rope seat 4 is inclined and arranged at an acute angle with the longitudinal rod 111 of the blade stem, and the inclination angle of the hub rope seat 4 is parallel or nearly parallel to the inclination angle of the stay rope 3, so as to reduce the force on the hub rope seat 4.

[0031] It can be understood that only two intersecting stay ropes can also be arranged on the blade stem of the present invention. For example, two stay ropes are arranged on the windward side and no stay rope is arranged on the leeward side.

[0032] It can be understood that a sheath, a rope clamp, etc. can be arranged on the stay rope; the stay rope can be a single rope or multiple ropes connected to each other through connection structures such as slings.

[0033] Embodiment 2

[0034] As Figure 2 shown: On the basis of Embodiment 1, in addition to arranging the hub rope seat 4 on the inner side of the longitudinal rod of the blade stem, a ring rope seat 7 is also arranged on the outer side of the longitudinal rod of the blade stem. The ring rope seat 7 is symmetrically arranged with the hub rope seat 4 to form a double rope seat. And a ring rope 6 is connected between the outer sides of adjacent blade stems, and the ring rope 6 is connected to the ring rope seat 7.

[0035] In this embodiment, by arranging the ring rope, the blade stems can be tightened between each other to form an annular stay rope structure, which can improve the strength of the entire wind wheel, eliminate the fatigue influence of the entire wind wheel, and improve the stability of the wind wheel rotation. Among them, the tension of the ring rope is greater than the tension of the stay rope. On the premise of ensuring the force balance of each blade stem, it can further ensure the anti-torsion and anti-centrifugal force performance of the wind wheel, and it is not easy to make the stay rope slack.

[0036] Embodiment 3

[0037] As Figure 2 shown: The difference from Embodiment 1 or 2 is that a shaft rope seat 9 is also arranged on the inner side of the longitudinal column of the blade stem 11, and the shaft rope seat 9 is arranged below the hub rope seat 4. A main shaft 8 is connected inside the hub 2, and the main shaft 8 can rotate under the drive of the hub 2, and then is connected to a generator set through a bearing seat to generate electricity for the generator. One end of the main shaft 8 extends into the hub 2 and is fixed, and the main shaft extends into the hub from one end and extends out from the other end. The extended end is connected with a flange 81, and there are connection parts, such as bolts, inside the flange 81. The stay rope 3 is buckled on the connection parts. That is, one end of the stay rope is connected to the flange and the other end is connected to the shaft rope seat, showing a tightened state.

[0038] In addition, stay ropes can also be arranged on the original hub rope seat 4 and C-shaped seat 5 at the same time and can also be used as a backup. For example, stay ropes are only arranged between the flange and the shaft rope seat, and the hub rope seat and C-shaped seat are used as a backup; or stay ropes are only arranged between the hub rope seat and C-shaped seat, and the flange and shaft rope seat are used as a backup. The present invention can be arranged according to different models of wind wheels.

[0039] In this embodiment, by arranging a stay rope between the blade stem and the main shaft, the functions of resisting centrifugal force and torsional force are also achieved.

[0040] In summary, on the one hand, the present invention can not only reduce the centrifugal force and torsional force generated by the rotation of the blades, improve the anti-fatigue performance of the impeller, and have a certain degree of lightweight; on the other hand, it can ensure that the stay rope is not easily broken. Moreover, by combining the loop rope, on the premise of ensuring the balanced force of each blade stem, the anti-torsion and anti-centrifugal force performance of the wind wheel can be further ensured, and the stay rope is not easily loosened.

Claims

1. A wind blade and hub connection system, wherein the wind blade includes a blade stem; characterized in that, A stay rope is provided between the blade stem and the hub and / or between the blade stem and the main shaft provided on the hub, and the stay rope is in a tensioned state; one end of the stay rope is connected to the inner side of the blade stem, and the other end is connected to the edge side of the hub; at least two criss-crossed stay ropes are provided between the blade stem and the hub, or at least two stay ropes that are inclined towards each other and do not cross are provided between the blade stem and the main shaft inside the hub; the blade stem is a truss structure, and at least one rope seat for connecting the stay rope is provided on the rod body of the truss, and the rope seat is inclined.

2. The wind blade and hub connection system according to claim 1, wherein, The main shaft is fixed inside the hub, and a connecting portion is provided on the main shaft, and the stay rope is connected to the connecting portion of the main shaft.

3. The wind blade and hub connection system according to claim 1, characterized in that, The connection points of the stay rope with the blade stem and the hub are arranged diagonally, one connection point is provided on the inner side of the blade stem, and the other connection point is provided on one side of the surface where the hub is connected to the blade stem.

4. The wind blade and hub connection system according to claim 1 or 2 or 3, characterized in that, The hub is a polyhedron structure, a cylinder is provided between two adjacent surfaces connecting the blade stem, and the stay rope is connected to the cylinder; or a flange is provided on the main shaft, and the flange extends along the hub, and the stay rope is connected to the flange.

5. The wind blade and hub connection system according to claim 3, characterized in that, A C-shaped seat is provided at the connection point of the hub, and stay ropes can be connected between the hub and the blade stems on both adjacent sides at the same time.

6. The wind blade and hub connection system according to claim 1, characterized in that, The wind blade further includes a blade body, the blade stem is arranged inside the blade body, and one end extends along the blade body to be connected to the hub, and the stay rope is connected to the extended section of the blade stem.

7. The wind blade and hub connection system according to claim 1, characterized in that, The rope seat is a double-rope seat, one of the rope seats in the double-rope seat is arranged on the inner side of the blade stem, and the other rope seat is arranged on the outer side of the blade stem, and they are symmetrically arranged; and a loop rope is connected between the outer sides of adjacent blade stems, and the loop rope is connected to the rope seat on the outer side of the blade stem.

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