JP3733574B2 - Sliding bearing of variable stator blade for gas turbine - Google Patents

Description

[0001]
[Industrial application fields]
The present invention relates to a sliding bearing for a variable stationary blade for a gas turbine, and more particularly to a sliding bearing for a variable stationary blade for a gas turbine used in an aircraft, a vehicle, a ship, a power generation facility, and the like.
[0002]
[Prior art]
A gas turbine is a gas prime mover that compresses gas and heats it to extract the output to the outside by expanding the generated high-temperature and high-pressure gas in the turbine.
In recent gas turbines, the trend toward higher temperatures and higher pressure ratios is significant.
A plurality of plain bearings for a variable stationary blade for a gas turbine support the variable stationary blade in a swingable manner, and are provided along the inner peripheral surface of a turbine or compressor casing.
[0003]
Teflon materials are generally used for bearings used for compressors at temperatures of 200 ° C. or lower. When using Teflon material, there is no need to prevent rotation.
[0004]
With the recent increase in the temperature of gas turbines, for example, when the temperature becomes higher than 200 ° C., the Teflon material cannot be used, and metal or ceramics must be used.
[0005]
A conventional sliding bearing for a variable stationary blade for a gas turbine has a configuration as shown in FIG. 3, for example. FIG. 3 is a side sectional view of a conventional sliding bearing for a variable stationary blade for a gas turbine.
[0006]
In FIG. 3, the rotating shaft b of the variable stator vane a is supported by a bearing c, which is made of Teflon and is fitted to a casing d. The variable stationary blade a adjusts the angle by the operation of a drive lever e fixed to the end of the rotating shaft b by a nut f, and controls the flow rate of gas flowing into the moving blade and the inflow angle in the turbine or compressor. . g is a washer inserted between the drive lever e and the casing d, and h is a rotating surface of the gas turbine.
[0007]
[Problems to be solved by the invention]
When the bearing c is made of Teflon, there is no particular detent as shown in the figure, and there is no particular problem even if the bearing c rotates with the rotary shaft b in the casing d. However, when the bearing is at a high temperature exceeding 200 ° C., metal and ceramics are also used for the bearing c. In this case, when the bearing c rotates with the casing d, particularly the inner part of the casing d is abnormally worn. There is a fear, and a rotation stopper is required between the bearing c and the casing d.
[0008]
However, when the above-described sliding bearing c of the variable turbine vane for gas turbine is fixed in the casing d with a key or a pin (not shown), stress concentration occurs in the bearing c or the casing d, causing cracking. Otherwise, deformation or damage may occur.
[0009]
Further, in the example of FIG. 3, since the rotating shaft b is supported by one bearing c, when the bearing gap is large or the load is large, the rotating shaft b is inclined to cause one-side contact. The surface pressure increases, and excessive wear and friction torque are likely to increase.
[0010]
The present invention is intended to solve the above-described problems, and supports the rotating shaft of a variable stationary blade even when a metal or ceramic having low toughness is used for a bearing as the temperature of a gas turbine increases. It is an object of the present invention to provide a sliding bearing for a variable stationary blade for a gas turbine in which the bearing does not rotate in the bush and the rotating shaft and the bearing do not come into contact with each other.
[0011]
[Means for Solving the Problems]
In order to achieve the above object, the gas turbine variable stator blade slide bearing of the present invention is a gas turbine turbine or compressor variable stator blade slide bearing,
The inner bearing has an inner bearing and an outer bearing that support the rotating shaft of the variable stator blade on the inner side and the outer side. The inner bearing has an inner end abutting on the inner bush and an outer end abutting on the outer bush. The outer bearing is fitted into the outer end of the outer bush, the outer bush and the inner bush are fixed to the casing, the outer end surface of the inner bearing and the inner end surface of the outer bush. Are inclined at a required angle with respect to a plane perpendicular to the axis of the rotation shaft so as to contact each other.
[0012]
[Action]
According to the sliding bearing of the variable stationary blade for gas turbine configured as described above, the rotating shaft of the variable stationary blade is supported by the inner bearing and the outer bearing, and the outer end face of the inner bearing and the inner end face of the outer bush rotate. The bearings are fixed in the inner bush and do not rotate because they are in contact with each other at a required angle with respect to a plane perpendicular to the axis of the shaft. Further, the rotating shaft and the bearing of the variable stationary blade do not come into contact with each other.
[0013]
【Example】
Hereinafter, preferred embodiments of the present invention will be described with reference to the drawings. 1 and 2 show an embodiment of the present invention. FIG. 1 is a side sectional view of a plain bearing of a variable stationary blade for a gas turbine, and FIG. 2 is a view taken along the line AA of FIG.
[0014]
In the figure, reference numeral 1 denotes a variable stationary blade for a gas turbine that is directly connected to a rotating shaft 2. Reference numeral 3 denotes an inner bearing that supports the inner side of the rotating shaft 2, and reference numeral 4 denotes an outer bearing that supports the outer side of the rotating shaft 2. The inner bearing 3 and the outer bearing 4 support the rotating shaft 2 at two places. The inner bearing 3 has a cylindrical shape, and an inner end thereof is in contact with the inner bush 7 and an outer end thereof is in contact with the outer bush 6.
[0015]
The outer bearing 4 has a cylindrical shape having a flange 4 a on the outer side, and is fitted into the outer end of the outer bush 6. A gap 16 is provided between the outer peripheral surface of the rotating shaft 2 and the inner peripheral surface of the outer bush 6 between the inner bearing 3 and the outer bearing 4.
[0016]
As shown in FIG. 2, a screw portion 8 and a square drive lever fitting portion 11 are provided at the tip of the rotating shaft 2, and the drive lever 5 has a square hole. It is fitted to the part 11 and is fixed by a nut 10. Instead of the drive lever 5, for example, a drive mechanism using a rack and a pinion may be used.
[0017]
The outer bush 6 and the inner bush 7 are overlapped with a flange 6 a provided so as to project at the center of the outer peripheral surface of the outer bush 6 and a flange 7 a provided at the outer end of the inner bush 7 with a fixing bolt 15. It is fixed.
[0018]
The outer end surface of the inner bearing 3 and the inner end surface of the outer bush 6 are inclined at a required angle α with respect to a plane perpendicular to the axis of the rotating shaft 2 and are in contact with each other.
[0019]
Reference numeral 12 denotes a washer with a tongue provided between the drive lever 5 and the nut 10. One end of the tongue is bent toward the nut 10 and one end thereof is bent toward the drive lever 5. 13 is a washer provided between the outer bearing 4 and the drive lever 5, 14 is a concave relief provided on the outer peripheral surface of the outer bush 6, and 16 is a gap between the outer peripheral surface of the rotating shaft 2 and the outer bush 6. It is. 17 is a rotating surface of the gas turbine, and 18 is a gas fluid.
[0020]
Next, the operation of the above embodiment will be described.
The rotating shaft 2 is supported by an inner bearing 3 and an outer bearing 4 and is rotated by the operation of a drive lever 5 to adjust the angle of the variable stationary blade 1, and the gas flow rate and inflow flowing to the moving blade in the turbine or the compressor. Control the angle. The variable stationary blade 1 is subjected to a load by the gas fluid 18, and the force is borne by the inner bearing 3 and the outer bearing 4 that support the rotating shaft 2.
[0021]
Thus, since the rotating shaft 2 of the variable stator blade 1 is supported by the inner bearing 3 and the outer bearing 4, there is little contact between the rotating shaft 2 and the bearing.
[0022]
The inner bearing 3 tries to rotate by friction with the rotating shaft 2, but the outer end surface thereof and the inner end surface of the outer bush 6 are inclined at a required angle α with respect to a plane perpendicular to the axis of the rotating shaft 2. Since they are in contact with each other, they cannot rotate and are securely fixed in the inner bush 7. Although the outer bearing 4 has no rotation stop, the outer bearing 4 has a low temperature, so there is no fear of harming with the rotating shaft 2.
[0023]
【The invention's effect】
As described above, according to the sliding bearing of the variable stationary blade for gas turbine of the present invention, the rotating shaft of the variable stationary blade is supported by the inner bearing and the outer bearing, and the outer end surface of the inner bearing and the inner end surface of the outer bush. Are inclined at a required angle with respect to a plane perpendicular to the axis of the rotary shaft and are in contact with each other, so that the inner bearing can be securely fixed in the inner bush. Furthermore, even if the load is large, the rotating shaft is not inclined and does not come into contact with one another, so that it is possible to prevent the excessive wear and the increase in the friction torque, thereby providing excellent effects.
[Brief description of the drawings]
FIG. 1 is a side sectional view of a sliding bearing of a variable stationary blade for a gas turbine showing an embodiment of the present invention.
FIG. 2 is a view taken in the direction of arrows AA in FIG.
FIG. 3 is a side sectional view of a conventional one.
[Explanation of symbols]
DESCRIPTION OF SYMBOLS 1 Variable stator blade 2 Rotating shaft 3 Inner bearing 4 Outer bearing 4a Outer bearing flange 5 Drive lever 6 Outer bush 7 Inner bush 7a Inner bush flange 8 Screw part 9 Casing 10 Nut 11 Drive lever fitting part 12 Washer with tongue 13 Washer 14 Relief 15 Fixing bolt 16 Frame 17 Gas turbine rotating surface 18 Gas fluid a Variable vane b Rotating shaft c Bearing d Casing e Drive lever f Nut g Washer h Gas turbine rotating surface

Claims (1)

A sliding bearing for a variable vane of a turbine or compressor of a gas turbine,
The inner bearing has an inner bearing and an outer bearing that support the rotating shaft of the variable stator blade on the inner side and the outer side. The inner bearing has an inner end abutting on the inner bush and an outer end abutting on the outer bush. The outer bearing is fitted into the outer end of the outer bush, the outer bush and the inner bush are fixed to the casing, the outer end surface of the inner bearing and the inner end surface of the outer bush. Is a sliding bearing for a variable stationary blade for a gas turbine, characterized in that it is inclined at a required angle with respect to a plane perpendicular to the axis of the rotating shaft and is in contact with each other.

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