JPS6217306A - Rotary machine vane - Google Patents

Abstract

PURPOSE:To aim at the reduction of vibrational stress by loosely fitting a movable piece between the vane root part of a rotary vane and a rotary disc. CONSTITUTION:The vane root part 3 of a rotary vane 4 is planted on a rotary disc 12. A groove 6a, being directed outward at the radial direction, is formed on the rotary disc 12 between the vane root part 3 and the adjacent vane part 3. A movable piece 6 is loosely fitted to the groove 6a so as to prevent the disconnection thereof by a disconnection suppressing piece 21. Therefore, the movable piece 6a is slightly moved in the groove 6a and thereby the damping energy is generated between the vane root part and the rotary disk 12 so that it is possible to reduce vibrational stress generated on the vane.

Description

DETAILED DESCRIPTION OF THE INVENTION [Field of Industrial Application] The present invention relates to improvement of the blade root portion of a rotary machine blade such as a turbine blade, a compressor blade, a prower blade, or the like.

[Conventional technology]

5 to 7 are diagrams showing conventional examples of single-rotation mechanical blades. Conventionally, side entry type blade roots of rotary machine blades have shapes shown in FIGS. 5 and 6.

In FIG. 5, reference numeral 1 denotes a rotating shaft, and 2 denotes a rotating disk that is integrally connected to the rotating shaft 1 or connected by shrinkage fit.

Reference numeral 3 indicates a blade root portion of the rotary machine blade, and 4 indicates a fluid passage portion (also referred to as a blade profile portion or blade effective portion) of the rotary machine blade.

The blade root 3 and rotating disk 2 are as shown in FIG.

The blade root portion 3 is inserted into the outer circumferential recess of the one-rotation disk 2 by using the interlocking uneven portions to mechanically connect the blade root portion 3.

This structure can withstand the centrifugal force that occurs when the blade profile section 4 rotates at high speed, and the blade can also be
The structure is designed to withstand vibrations caused by external force.

It has had a good track record in the past.

However, in recent years, the output of rotating machines has increased significantly. Correspondingly, the vibration stress of single-rotation mechanical blades has generally increased, and there is an urgent need to reduce the vibration stress particularly at the blade root portion of the blade.

[Problem that the invention seeks to solve]

As mentioned earlier, when the output of a one-rotation machine increases, the fluid force acting on the blade increases, and the resulting vibration stress increases, but the vibration mode is, for example.

In the case of the bending mode in the circumferential direction of the disk, the cross section taken along the line ■-■ in FIG. 6 (point 8a) shown in the seventh factor.

3b, 3c, 3d) section constant z
, =a·b2/6 is larger, the vibration stress of the blade can be in one region.

However, with the conventional blade root structure, it is difficult to increase the section modulus 2. In addition, since the connection between the blade root 3 and the rotating disk 2 is strongly connected by centrifugal force, there is no relative slip that would cause sufficient structural damping during vibration, so it is not possible to sufficiently reduce vibration stress by structural damping. I could not do it.

[Means for solving problems]

The present invention is a rotary machine blade characterized in that a movable piece is loosely fitted between a blade root of a blade implanted in a rotary disk of the rotary machine and the rotary disk.

[Effect]

In the present invention, a groove is provided between the blade root of a one-rotation mechanical blade and the above-mentioned rotating disk, and a movable piece is loosely fitted into the groove. The number of contact points increases, and the friction and impact at each contact surface causes structural damping to be greater than in conventional models.

〔Example〕

1 to 2 are diagrams showing an embodiment of the present invention.

This embodiment differs from the conventional example shown in FIGS. 5 to 7 in that the rotating disk 12 between adjacent blade roots 3 of the blades installed in the rotating disk 12 of a one-rotation machine is A groove 6a is provided in the outer radial direction, and the movable piece 6 is loosely fitted into the groove 6a.

It should be noted that the same reference numerals in FIG. 1 as those in FIGS. 5 to 7, which indicate the conventional example, have almost the same structure, and the explanation thereof will be omitted.

In this embodiment, the movable piece 6 is connected to the rotating disk 1 during operation of the rotating machine.
2, the retainer 21 is inserted into the groove 6 in the axial direction to prevent it from falling off.
It is fixed at both ends inside a. This can be accomplished by caulking the nine-turn disc 12 after inserting the movable piece 6 into the groove 6a.

With this structure, the movable piece 6 moves slightly within the groove 6a, and damping energy is generated between the blade root 3 and the rotating disk 12, thereby reducing the vibration stress of the mechanical blade per rotation.

FIGS. 3 and 4 are diagrams showing other embodiments of the present invention. This embodiment is different from the previous embodiments in that the blade root 13 of a single-rotation mechanical blade is branched into two, and a groove N edge membrane is provided between two adjacent blade roots 13 and the blade root 13 and rotating disk 22. The movable piece 16 is loosely fitted to increase the number of contact points.

In addition, in this embodiment, a claw-shaped stopper 81 is provided to prevent the movable piece 16 from falling off the rotating disk 22 during operation of the rotating machine.
are provided on the axial side of the blade root portion 18. It is sufficient to do this by loosely fitting the movable piece 16 into the groove 16a and then caulking the blade root 18. Experimental results using the above two embodiments of the present invention showed that vibration stress could be reduced to 1/2 to 1/10 compared to the conventional example without a movable piece.

〔Effect of the invention〕

By loosely fitting a movable piece between the blade root of a blade installed on the rotating disk of a rotating machine and the rotating disk, it is possible to connect the adjacent blade root to the movable piece or the same movable piece to the rotating disk. The present invention greatly contributes to the development of industry, such as increasing the contact surface and increasing the damping capacity.

[Brief explanation of drawings]

1 to 2 are diagrams showing one embodiment of the present invention, and FIG. 1 is a diagram showing an assembly state of main parts of a rotating machine.
FIG. 2 is a front view as viewed from the I-line arrow, and FIG. FIGS. 3 and 4 are diagrams showing other embodiments of the present invention. 3 is a front view taken along the line 1-11I in FIG. 4 showing the state of assembly of the main parts, and FIG. 5 to 7 are views showing conventional examples according to the present invention. FIG. 5 is a front view of main parts assembled, FIG. 6 is a perspective view of the wing, and FIG. ■It is a sectional view taken along the line. 1...Rotating shaft, 2,12.22...Rotating disk, 3°13...Blade root of rotary machine blade, 6.16...Movable piece. 6a, 16a...Groove.

Claims (1)

[Claims] 1. A rotary machine blade, characterized in that a movable piece is loosely fitted between a blade root of a blade implanted in a rotary disk of the rotary machine and the rotary disk.