JPH05149237A - Variable pitch device for windmill - Google Patents

Abstract

PURPOSE:To provide a variable blade pitch device of easy maintenance at a low cost. CONSTITUTION:A rod 7 is inserted into a through hole, provided in the center of a main rotary shaft 3, and moved longitudinally by a hydraulic cylinder 9 behind the main rotary shaft 3. A rod point end is connected to the root of a blade 1 by a link mechanism 6 to change a pitch angle of the blade 1 by longitudinal motion of the rod 7. Since necessity for providing a hydraulic system and an electric system to the inside of a rotor head 2 is eliminated, oil is prevented from scattering to the outside, even when the oil leaks in an emergency, by simplifying a structure and facilitating also maintenance.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a blade pitch varying device for a propeller type wind turbine generator.

[0002]

2. Description of the Related Art FIG. 3 is a vertical sectional view showing an example of a conventional propeller type wind turbine generator. The main body of the propeller type wind turbine generator is installed on the top of the tower (01), and has a blade (02), a blade connecting shaft (03), a rotor head (0).
4), a planetary gearbox (06) with a built-in main shaft (05), a generator (07), and a blade pitch variable mechanism for operating the blade angle.

The blade pitch varying mechanism controls the computer so that the blade pitch is in accordance with the wind speed in order to keep the generator output constant. The components include a hydraulic unit (08), a servo valve (09), an accumulator (010), a rotary joint (011), a hydraulic cylinder (012), a link (013), a blade pitch position detecting potentiometer (014), and a slip. Ring (0
15). The hydraulic cylinder (012) and potentiometer (014) are mounted on the rotating rotor head (0
4), the rotary joint (011) for transmitting hydraulic pressure from the stationary portion to the rotating portion and the slip ring (015) for transmitting electricity are required. Further, when an abnormality occurs during operation of the power generator, a mechanism for interrupting the input and stopping the operation is required as an emergency stop measure. For that purpose, an accumulator (010) is provided in the hydraulic system.

[0004]

The conventional blade pitch varying device for a wind turbine has the following problems to be solved. 1) Because of its function, the rotary joint has a rotating part and a stationary part, and slides between them, so wear is inevitable and replacement is necessary. 2) The slip ring requires maintenance, although it depends on the type, but with the sliding type, life problems and disconnection problems due to vibration occur. 3) Due to the structure, the maintenance space inside the rotor head is narrow, and it is difficult to maintain rotary joints and slip rings. 4) It is necessary to pass oil holes (3) and cables through the stationary part of the planetary gearbox, but since the pressure inside the oil holes is as high as 120 kg / cm ² , strict measures against oil leakage are necessary. .. 5) Since there is a hydraulic system inside the rotor head, if oil leaks, it will scatter outside, causing problems such as dirt on the tower and ground pollution. 6) During an emergency stop, the blade pitch is operated and held at the feathering position by the hydraulic pressure and accumulator pressure. However, if the station electricity is lost and the electricity in the station is lost, the pump stops and the hydraulic pressure is lost. It becomes impossible to do so, and the blade (rotating part) turns around due to the wind force, which is a problem.

[0005]

SUMMARY OF THE INVENTION In order to solve the above-mentioned conventional problems, the present invention provides a rotor head having a plurality of blades attached, and a tip portion attached to the rotor head. A main rotating shaft having a through hole, a two-axis parallel gearbox connecting the main rotating shaft to a generator, a rod inserted in the through hole and capable of reciprocating in the longitudinal direction, a tip portion of the rod, and the blade. Link mechanism provided between the base and the root of the hydraulic cylinder, a hydraulic cylinder provided at the rear of the main rotary shaft and having a piston rod attached to the base of the rod, and an emergency stop provided in the through hole. A pitch variable device for a wind turbine, which is characterized by comprising a spring for use.

[0006]

Since the present invention is configured as described above,
It has the following effects. 1) Since the two-axis parallel gearbox is adopted, the hydraulic cylinder can be arranged behind the end of the main rotary shaft by passing the rod through the through hole provided at the center of the main rotary shaft. Therefore, the hydraulic system and the electric system can be provided on the stationary part side, and the maintenance space can be widened to facilitate the work. 2) A slip ring, rotary joint, and accumulator are not required, resulting in cost reduction and labor saving in maintenance. 3) Since high pressure oil does not pass through the parts of the stationary part of the gearbox,
Design and manufacture of gearbox becomes easy. 4) Even if oil leaks from the hydraulic system, it can be prevented from splashing outside. 5) By providing a spring for emergency stop in the through hole of the main rotating shaft, the blade pitch can be held at the feathering position by the force of this spring even when the electricity in the office is lost.

[0007]

1 is a perspective view showing an embodiment of the present invention, FIG.
Is also a vertical sectional view.

Wind rotational energy is generated by the blade (1)
It is transmitted from (three) to the rotor head (2) and the main shaft (3). Then, it is accelerated to a rated speed by a biaxial parallel gearbox (4) incorporating the main shaft (3) and transmitted to a generator (5) to be converted into electric energy.

The blade pitch changing mechanism comprises a link (6), a rod (7), an emergency stop spring (8), a hydraulic cylinder (9) and a potentiometer (10), and changes the blade pitch according to the wind speed. At the time of emergency stop, the blade is operated to the feathering position by the hydraulic pressure and the force of the spring (8), and even if the hydraulic pressure is lost, the position can be maintained only by the force of the spring (8). The hydraulic system and electric system are all located in a wide maintenance space on the stationary side.

[0010]

According to the present invention, the following effects can be obtained. 1) Maintenance can be saved. 2) The structure is simple and the overall cost can be reduced. 3) Even if an oil leak occurs, it can be treated without scattering it to the outside. 4) The blade pitch can be mechanically held at the emergency stop position (feathering state).

[Brief description of drawings]

FIG. 1 is a perspective view of a wind turbine generator according to an embodiment of the present invention.

FIG. 2 is a vertical cross-sectional view of FIG.

FIG. 3 is a vertical cross-sectional view showing an example of a conventional propeller-type wind turbine generator.

[Explanation of symbols]

 (1) Blade (2) Rotor head (3) Main shaft (4) Two-axis parallel speed increasing device (5) Generator (6) Link (7) Rod (8) Emergency stop spring (9) Hydraulic cylinder (10) Potentiometer

Claims (1)

[Claims] 1. A rotor head having a plurality of blades attached, a main rotary shaft having a tip end attached to the rotor head and having a through hole along an axial center, and the main rotary shaft connected to a generator. A two-axis parallel gearbox, a rod that is inserted into the through hole and can reciprocate in the longitudinal direction, a link mechanism that is provided between the tip of the rod and the root of the blade, and the main rotating shaft. A pitch variable device for a wind turbine, comprising: a hydraulic cylinder provided at a rear portion of the rod, and a piston rod attached to a root portion of the rod; and an emergency stop spring provided in the through hole.