JPH07310645A - Windmill blade - Google Patents

Abstract

PURPOSE:To eliminate the need for the blade guide of a windmill blade, to simplify structure, and to reduce weight by a method wherein a blade part is supported through a revolving wheel bearing simultaneously supporting a radial load and a thrust load, in a windmill blade having a blade part supported to a rotor head in such a manner that a pitch is variable. CONSTITUTION:In a windmill used for wind power generation, a four-point support type revolving wheel bearing 1 to simultaneously support loads in a radial direction and a thrust direction is prepared. The outer wheel 11 of the bearing 1 and a rotor head 3 are intercoupled by means of a bolt and the inner wheel 12 of the bearing 1 and the coupling shaft 2 of a blade part 6 and a blade 5 on the rotor head 3 side are intercoupled by means of a bolt. A drive part 4 is coupled to a plate 5 on the rotor head 3 side and a rotational drive force generated by the drive part 4 is transmitted to a blade part 6 through the coupling shaft 2 to vary the pitch of the blade part 6. By using the revolving wheel bearing 1 this way, the structure of a coupling part between the coupling shaft 2 and the rotor head 3 is simplified and weight is relieved.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a wind turbine blade in a wind turbine applied to wind power generation and the like.

[0002]

2. Description of the Related Art FIG. 2 is an explanatory view of a wind turbine blade in a conventional wind turbine used for wind power generation and the like. In the figure,
In the conventional wind turbine blade, the blade portion 3f and the rotor head 3 are connected by the deep groove type ball bearing 3a, the connecting shaft 3b, the blade guide 3c, etc., and by the rolling radial thrust bearing mechanism and the blade guide 3c by the ball bearing 3a. The sliding radial bearing 3d mechanism supports the connecting shaft 3b. Usually, the load in the thrust direction of the ball bearing 3a due to the centrifugal force generated by the rotation of the rotor head 3 is applied to the connecting shaft 3b of the wind turbine blade, and the blade portion 3
Aerodynamic force acting on f (including fluctuation component due to changes in wind speed and wind direction), sliding radial bearing 3d due to blade 3f own weight, radial load, aerodynamic force acting on blade part 3f (variation component due to changes in wind speed and wind direction) (Including) and bending moment due to the blade's own weight.

[0003]

As described above, in the conventional wind turbine blade, the deep groove type two-point support type ball bearing 3a for supporting the connecting shaft 3b in the radial direction, the blade guide 3c and the connecting shaft 3b. It has a structure to be supported at two places by the sliding radial bearing 3d between them, and the structure at the connecting portion between the blade portion 3f and the rotor head 3 becomes complicated and the weight also increases.
Further, since the sliding radial bearing 3d portion by the blade guide 3c has a large friction coefficient, a heavy load is imposed on the linkage mechanism 3e required to rotate the blade portion 3f to change the pitch.

[0004]

SUMMARY OF THE INVENTION A wind turbine blade according to the present invention is intended to solve the above-mentioned problems, and in a wind turbine blade in which a rotor head supports a blade portion with a variable pitch and rotates, a radial load and a thrust load are applied. And the wing portion are supported via a slewing ring bearing capable of simultaneously supporting and.

[0005]

That is, in the wind turbine blade according to the present invention, the blade portion of the wind turbine blade that rotates the blade portion by the rotor head while supporting the blade portion with a variable pitch provides the slewing ring bearing capable of simultaneously supporting the radial load and the thrust load. By supporting the blade portion via the slewing ring bearing capable of simultaneously supporting the radial load and the thrust load, the blade guide in the conventional wind turbine blade can be omitted. Therefore, since the slide bearing by the blade guide is also abolished, the friction coefficient when rotating the blade portion and changing the pitch becomes small.

[0006]

1 is an explanatory view of a wind turbine blade according to an embodiment of the present invention. In the figure, the wind turbine blade according to the present embodiment is for a wind turbine used for wind power generation, etc., and is capable of simultaneously supporting a radial load and a thrust load in place of a deep groove type ball bearing in a conventional wind turbine blade. The four-point support type slewing ring bearing 1 that can be used is also used, and the sliding radial bearing by the blade guide is also eliminated, so that the weight is reduced and the friction coefficient when rotating the blade portion 6 to change the pitch becomes small. , The load on the linkage mechanism required to change the pitch is lightened, and the size can be reduced. That is,
As shown in the figure, the rotor head 3 and the outer ring 11 of the slewing ring bearing 1 of the four-point support type are connected by bolts to form a slewing ring bearing 1
The inner ring 12 is connected to the connecting shaft 2 of the blade portion 6 and the plate 5 on the rotor head 3 side by bolts. The plate 5 on the rotor head 3 side is connected to the drive unit 4, and the rotational drive force generated by the drive unit 4 is transmitted to the connecting shaft 2 and the blade unit 6 so that the pitch of the blade unit 6 can be smoothly changed. It has become. The slewing ring bearing 1 has sufficient strength against the weight of the blade portion 6 and the centrifugal force and moment generated by the rotation of the rotor head 3. The slewing ring bearing 1 uses a ball type so that it can swivel sufficiently smoothly even if grease for lubrication leaks out and a seizure prevention effect is obtained, but a roller type may be used. Further, the balls in the slewing ring bearing 1 make almost linear contact with the groove-shaped ball guides engraved in the outer ring 11 and the inner ring 12 at four points of the arcs 11a, 11b, 12a, 12b, and the load applied to the inner ring 12. Is supporting. In this way, four-point support is possible because the swirling speed when rotating the blade 6 to change the pitch is slow, so there is no need to consider friction and the like as compared with bearings for high-speed rotating shafts and the like. Because.

A conventional wind turbine blade has a structure in which a connecting shaft is supported at two places, a deep groove type two-point support type ball bearing for supporting a load in a radial direction and a sliding radial bearing between the blade guide and the connecting shaft. Therefore, the structure of the connecting portion between the blade portion and the rotor head becomes complicated and the weight also increases. further,
Since the sliding radial bearing portion by the blade guide has a large friction coefficient, a heavy load is imposed on the linkage mechanism required to rotate the blade portion and change the pitch. However, in this wind turbine blade, the rotor head 3 and the blade portion 6 are connected. A slewing ring bearing 1 of a four-point support type capable of simultaneously supporting a load in the radial direction and a load in the thrust direction is used in a connecting portion with the shaft 2, and an inner ring 12 of the slewing ring bearing 1 and a wing portion 6 are connected. The shaft 2 and the drive unit 4 having the blade portion 6 pitch are integrated to form an outer ring 11 of the slewing ring bearing 1.
The rotor head 3 is integrated with the rotor head 3 so that the blade portion 6 can freely rotate to change the pitch of the blade portion 6 even when the rotor head 3 is rotating, and the load in the radial direction and the load in the thrust direction can be changed. By using the slewing ring bearing 1 capable of supporting both and at the same time, the structure of the connecting portion between the connecting shaft 2 of the blade portion 6 and the rotor head 3 is simplified and the blade guide in the conventional wind turbine blade can be omitted. It is possible, and the weight is reduced by omitting the wing guide. Further, the rotation when changing the pitch of the wing portion 6 is caused only by the rolling of the balls in the slewing ring bearing 1, and the friction coefficient becomes smaller than in the case of using the conventional sliding radial bearing together. The mechanical load is small. Further, in the present wind turbine blade, for example, a blade guide having a weight of about 400 kg can be omitted, and since the strength is increased by using the slewing ring bearing 1, the ball bearing of about 30 kg is replaced with the slewing ring bearing 1 of about 150 kg. The weight is reduced by about 280kg per connecting part. Since a normal wind turbine has three blades 6, a total weight of about 840 kg is reduced. Further, the friction coefficient of the sliding radial bearing between the connecting shaft and the shaft guide in the conventional wind turbine blade is about 0.1, but the friction coefficient is about 0.01 in the structure of only the spherical swivel bearing 1. , Wings 6
The load on the drive unit 4 and its linkage mechanism, which rotate to change the pitch, is significantly reduced.

[0008]

The wind turbine blade according to the present invention is constructed as described above, and since the blade guide in the conventional wind turbine blade can be omitted, the structure of the connecting portion between the blade portion and the rotor head can be simplified. And the weight is reduced. Further, since the friction coefficient when rotating the blade portion to change the pitch is reduced, the load on the drive unit and the linkage mechanism for changing the pitch of the blade portion is reduced.

[Brief description of drawings]

FIG. 1 (a) is a sectional view of a connecting shaft in a wind turbine blade according to an embodiment of the present invention, and FIG. 1 (b) is a sectional view of a slewing wheel bearing thereof.

2A is a sectional view of a rotor head in a conventional wind turbine, and FIG. 2B is a sectional view of a connecting shaft thereof.

[Explanation of symbols]

 1 slewing wheel bearing 2 connecting shaft of blades 3 rotor head 4 drive unit 5 drive side plate 6 blade unit

[Procedure amendment]

[Submission date] June 13, 1994

[Procedure Amendment 1]

[Document name to be corrected] Drawing

[Name of item to be corrected] Figure 1

[Correction method] Change

[Correction content]

[Figure 1]

Claims (1)

[Claims] 1. A wind turbine blade, in which a rotor head supports a blade portion with a variable pitch for rotation, wherein the blade portion is supported via a slewing ring bearing capable of simultaneously supporting a radial load and a thrust load. And a windmill wing.