JPS601380A - Bearing unit for wind-driven electricity generation apparatus - Google Patents

Abstract

PURPOSE:To prevent the bending load and thrust of a propeller from acting to the bearing of an overdrive in a wind-driven electricity generation apparatus in which the rotary power of the propeller is transmitted to an electricity generator through the overdrive, by providing two bearings between the propeller and the overdrive. CONSTITUTION:A propeller 1 is rotated by the pressure of natural wind. The rotatory power of the propeller 1 is transmitted to a transmission shaft 3 through a hub 2. An electricity generator 5 is driven, by an overdrive 4, at a higher revolution speed than the shaft 3. An intermediate transmission shaft 11 is provided between the hub 2 and the overdrive 4 and supported by bearings 12a, 12b, which are supported on a bearing stand 13 and held by a bearing cover 14 so that the bearings are imovable in the axial direction. The bending load and thrust of the propeller 1 are thus prevented from acting to the bearing of the overdrive 4, so that the overdrive is kept safe.

Description

DETAILED DESCRIPTION OF THE INVENTION [Field of Application of the Invention] The present invention relates to a wind power generation device, and particularly to a bearing device for a propeller-type wind power generation device.

[Background of the invention]

The structure of a conventional propeller type wind power generator will be explained with reference to FIG.

The propeller windmill 1 rotates under the pressure of natural wind. The rotational force of the propeller windmill is transmitted to the transmission shaft 3 via the hub 2, and the rotational speed is increased by the speed increaser 4 to drive the generator 5.

Natural wind constantly fluctuates in wind direction and speed, but generators must maintain a constant rotational speed in order to maintain a constant output.

For this reason, the pitch angle of each propeller is controlled by the pitch control device 6 so that the number of rotations does not change even if the wind speed changes.

Additionally, if the propeller windmill rotates at a higher speed than the rated speed, the centrifugal force applied to the rotating part will become excessive and pose a danger to the mechanical strength, so if the rotation speed exceeds a predetermined number, the brake 7 will be activated to mechanically brake it. .

These generators are stored in the rear chamber 8, and the generator chamber is fastened to the main pillar 9. The tail nlo controls the direction of the wind receiving surface of the propeller wind turbine so that the propeller wind turbine can efficiently receive wind pressure in response to changes in wind direction.

In propeller wind turbines, the wind direction and speed are constantly changing, and the thrust is also constantly changing. In addition, the wind pressure applied to the front surface of the propeller wind turbine is uneven both vertically and horizontally. For example, in Fig. 1, if the wind pressure on the upper side of the wind turbine is Pl and the wind pressure on the lower side of the wind turbine is P2, and assuming that Pi>P2, a bending moment will be generated on the transmission shaft in the direction of the arrow, and this bending moment will be The direction and magnitude are constantly changing with changes in wind pressure.

In the conventional structure, the weight and thrust of the propeller wind turbine are supported by bearings built into the speed increaser.

However, in general, the bearings of the speed increaser do not have the strength to handle the load of the directly connected machine, so the bearings bear the weight of the propeller wind turbine.
If thrust is applied, it will cause an overload, which may cause damage to the gearbox itself, not to mention damage to the bearings.

Also, Publication No. 51-340. Japanese Patent Publication No. 53-5463
2, there is an example in which the propeller wind turbine and the bearing of the speed increaser are arranged to reduce the negative phase of the bearing of the speed increaser.

An example of a conventional bearing arrangement will be explained with reference to FIGS. 2 and 3.

FIG. 2 shows a load diagram when there is no bearing between the propeller wind turbine and the speed increaser, and FIG. 3 shows a load diagram when there is a bearing between the propeller wind turbine and the speed increaser.

The state of the load on the bearings 15a, 15b of the speed increaser in this state will be explained. To simplify the explanation, the load M applied to the transmission shaft is assumed to be only the weight of the propeller wind turbine, hub, and pitch control, and the load M applied to the transmission shaft is the thrust and fluctuating load caused by the weight of the transmission shaft and changes in wind pressure, or the rotating part of the speed increaser. Explain by ignoring the weight of

W: Sum of weights of propeller wind turbine, hub, and pitch control device [K9] Rs, R2: Reaction force of bearings 15a and 15b of speed increaser (
Kz] R3: Reaction force of bearing 16a [K9] L* 4 * Z2: Bearing span [(7)] In the case of Fig. 2, Rt = W 1 R2 R2 = 'A' X l 2 / L In the case of FIG. 3, Rt=V~X22/L R2=O R,s=W +Rx.

Even if a bearing is disposed between the propeller wind turbine and the speed increaser in this way, the bearing of the speed increaser is still affected by the above-mentioned own weight W.

[Purpose of the invention]

The purpose of the present invention is to reduce the bending load and thrust of a propeller wind turbine.
It is an object of the present invention to provide a bearing device for a wind power generator which has a structure that does not interfere with the bearing of the speed increaser, and which aims at the safety of the speed increaser.

[Summary of the invention]

The key point of the present invention is that two bearings are provided between the propeller wind turbine and the speed increaser.

[Embodiments of the invention]

An embodiment of the present invention will be described based on FIGS. 4 and 5.

An intermediate transmission shaft 11 is disposed between the hub 2 and the speed increaser 4, and the rotational force of the propeller is transmitted from the transmission shaft to the speed increaser via the intermediate power transmission shaft 11.

As shown in FIG. 5, a bearing 12a is attached to this intermediate transmission shaft 11.
, 12b are arranged. 13 is a bearing stand that supports the bearing;
The bearing is held down by a bearing cover 14 to prevent it from moving in the axial direction.

An example of the bearing arrangement of the present invention is shown in FIG. 6, and the bearing reaction force will be explained.

If the load W applied to the transmission shaft is the sum of the weights of the propeller wind turbine, hub, and pitch control device according to the calculation method for the conventional structure described above, then the bearing reaction force due to W is R1=O R2=O Ra = W 10R < 几4 = W X t2 / L.

The relationship between the self-weight of a propeller wind turbine and the reaction force of the gearbox bearing is the seventh
It is reduced as shown in the figure.

〔Effect of the invention〕

According to the present invention, it is possible to use a flexible coupling to reduce the bending stress of the transmission shaft caused by the shaft vibration and thrust induced by the wind pressure fluctuations that the propeller wind turbine receives, and the wind pressure difference on the wind receiving surface of the propeller wind turbine. can.

[Brief explanation of drawings]

Figure 1 is a cross-sectional view of a conventional propeller-type wind power generator;
3 is an arrangement diagram of a bearing with a conventional structure, FIG. 4 is a sectional view of a propeller-type wind power generator of the present invention, FIG. 5 is a sectional view of the main part of the present invention, and FIG. 6 is a sectional view of the present invention. bearing arrangement diagram, No. 7
The figure is a diagram showing a comparison of the effects on the conventional structure and the speed increaser of the present invention. Vine l concave number 21! ] Part 3

Claims (1)

[Claims] 1. A propeller-type wind power generation device that transmits the rotational force of a propeller wind turbine to a generator via a speed increaser, characterized by two bearings provided between the propeller wind turbine and the speed increaser. Equipment bearing device.