JPH06313440A - Damping structure of diaphragm joint - Google Patents

Abstract

PURPOSE:To enable axial vibration to be restrained by enlarging the axial stiffness to be applied to a diaphragm pack through a process of enabling large pressure-contact force to be obtained by centrifugal force. CONSTITUTION:A friction cylinder 11 is attached to a diaphragm attaching flange 2. A centrifugal spindle holder 13 supported by a long thin bolt 14 is arranged in the axial center part of a diaphragm pack 3. A centrifugal spindle 12 is held on the holder 13. One end of the long thin bolt 14 is insertd into a sleeve 15, and the other end is held to a shaft flange 4 through a bolt holder 18. Moreover, the sleeve 15 is held by the friction cylinder 11 through a rubber liner 17 fixed by means of a thimble 16. The centrifugal spindle 12 is brought in pressure contact with the inner surface of the friction cylinder 11 in rotating, so as to restrain the axial vibration.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a vibration control structure for a diaphragm joint applied to an output shaft system of a marine gas turbine.

[0002]

2. Description of the Related Art Diaphragm joints are used in the shaft systems of various rotary machines such as output shaft systems of marine gas turbines, and as flexible shaft joints that absorb the deviation of the shaft center.

Therefore, an example of a conventional diaphragm joint is shown in FIGS. 3 and 4, and its structure will be briefly described. A pair of diaphragm mounting flanges 2 connected to both sides of the intermediate shaft 1 (only the driven shaft side of the intermediate shaft 1 is shown in FIG. 3) are respectively connected to a diaphragm pack 3, and both diaphragm packs 3 are respectively connected to the driven shafts. The shaft flange 4 and the shaft flange of the drive shaft (not shown) (the other end side of the intermediate shaft 1) are integrally formed. In a marine gas turbine,
The shaft flange on the drive shaft side is connected to the output shaft of the gas turbine, and the shaft flange 4 on the driven shaft side is connected to the speed reducer.

An elastic arm 5 penetrating the inside of the diaphragm pack 3 is mounted on the diaphragm mounting flange 2 described above. As shown in FIG. 4, this elastic arm 5 has a slit 6 formed by wire cutting in the circumferential portion of a cylindrical member, and a tip 5a that receives centrifugal force during rotation is radially (indicated by a dashed arrow). It is configured so as to spread and come into pressure contact with the inner circumference of the cylindrical portion 7 formed integrally with the shaft flange 4. A liner member 8 is provided on the inner circumference of the cylindrical portion 7, and the tip 5 a is brought into pressure contact with the liner member 8.

[0005]

In the case of a marine gas turbine, the propeller shaft system may be displaced in the axial direction or axially due to the vibration of the hull due to wave forces. These are a long intermediate shaft 1 and a diaphragm. It is absorbed by the pack 3.
That is, the intermediate shaft 1 is inclined with respect to the displacement of the axial center, and the diaphragm pack 3 is elastically deformed in the axial displacement,
It is configured to protect the shaft system from each external force.

By the way, a diaphragm joint constituted by a pair of diaphragm packs and a long intermediate shaft vibrates in the axial direction, and its natural frequency is higher as the rigidity of the diaphragm pack is higher. However, if the rigidity is increased, the function of the flexible joint is deteriorated, and an unreasonable vibration stress is generated in the shaft system. Therefore, the natural frequency becomes lower than the normal speed, and when used in a wide speed range such as a marine turbine, it may be operated at a speed corresponding to the natural frequency, and the diaphragm pack may be damaged due to resonance. I'm worried. An elastic arm was considered as a countermeasure for this problem.

[0007] This elastic arm is elastically deformed outward by the centrifugal force of the rotation of the shaft system, and its tip is pressed against the shaft flange side to transmit a part of the torque, but its axial rigidity is in the diaphragm pack. It is added to suppress axial vibration.
However, it is difficult to obtain a large pressure contact force with the above-mentioned conventional structure, and therefore, the effect of damping the axial vibration is insufficient.

Therefore, an object of the present invention is to provide a vibration damping structure capable of obtaining a large pressure contact force by centrifugal force, and to improve the vibration damping effect of the axial vibration in the diaphragm pack.

[0009]

DISCLOSURE OF THE INVENTION The present invention is to solve the above-mentioned problems, and in a vibration damping structure of a diaphragm joint in which the rotation speed changes in a wide range, a friction cylinder fixed to a diaphragm mounting flange and a centrifugal force. A centrifugal weight that presses against the friction cylinder, a centrifugal weight holder that guides the centrifugal weight, an elongated bolt that holds the centrifugal weight holder, and one end of the elongated bolt that holds the friction cylinder integrally with the friction cylinder. A vibration damping structure for a diaphragm joint comprising a formed sleeve and a bolt holder that holds the other end of the elongated bolt and is integrally formed with a shaft flange of a driven shaft or a drive shaft.

A rubber liner may be interposed between the friction cylinder and the sleeve.

[0011]

According to the above-mentioned means, when the shaft system rotates, the centrifugal weight radially projects due to the centrifugal force and presses against the inner surface of the friction cylinder. Therefore, a large pressure contact force can be obtained, the axial rigidity added to the diaphragm pack is increased, and the axial vibration of the diaphragm joint is reliably suppressed.

Further, by interposing the rubber liner between the friction cylinder and the sleeve, the inclination of the diaphragm joint is absorbed by the rubber liner and the elongated bolt, and no fatigue stress occurs.

[0013]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENT An embodiment of the present invention is shown in FIGS. FIG. 1 is a vertical cross-sectional view of a diaphragm joint according to the present invention, and FIG. 2 is a horizontal cross-sectional view (cross section AA of FIG. 1).

A friction cylinder 11 is attached to the diaphragm attachment flange 2 formed integrally with the intermediate shaft 1.
A centrifugal weight 12 is provided at the center of the diaphragm pack 3 in the axial direction.
Centrifugal weight holder 13 for holding is supported by elongated bolts 14.

One end of the elongated bolt 14 is inserted into the sleeve 15. The sleeve 15 is held by the friction cylinder 11 via a rubber liner 17 fixed by a fitting ring 16. The other end of the elongated bolt 14 is held by the shaft flange 4 of the driven shaft or the drive shaft via the bolt holder 18. Reference numeral 19 is a nut.

As the above-mentioned rubber liner 17, silicon rubber or fluororubber having excellent heat resistance and aging resistance and high strength is generally used.

The operation of the vibration damping structure of the diaphragm joint according to the present invention will be described below. When a shaft system connected to a marine gas turbine (not shown) rotates, the intermediate shaft 1 and the diaphragm mounting flange 2, the friction cylinder 11, the rubber liner 17 are rotated.
The sleeve 15 and the like rotate together. Also, the intermediate shaft 1
Rotation is transmitted to the shaft flange 4 via the diaphragm pack 3, so the bolt holder 18 and the elongated bolt 1
4, the centrifugal weight holder 13, the centrifugal weight 12, etc. also rotate integrally. Since centrifugal force acts on the centrifugal weights 12 that rotate in this manner, each centrifugal weight 12 protrudes in the radial direction and the friction cylinder 11
Is strongly pressed against the inner surface of the.

When the centrifugal weight 12 and the inner surface of the friction cylinder 11 are brought into pressure contact with each other, a part of the driving torque of the marine gas turbine is transmitted through the pressure contact portion, and axial rigidity corresponding to the pressure contact force is generated. To do. Since this axial rigidity is added to the rigidity of the diaphragm pack 3, the diaphragm pack 3
The axial vibration of can be suppressed.

When the diaphragm joint is inclined, the rubber liner 17 and the elongated bolt 14 absorb it, so that no fatigue stress occurs.

[0020]

As described above, according to the present invention, a strong pressure contact force due to the centrifugal force can be obtained, so that the effect of suppressing the axial vibration of the diaphragm joint is improved, the diaphragm is damaged, and the bearing is damaged by the vibration. It is possible to prevent the trouble of operation failure due to large vibration alarm.

[Brief description of drawings]

FIG. 1 is a vertical cross-sectional view showing a vibration damping structure of a diaphragm joint according to an embodiment of the present invention.

FIG. 2 is a sectional view taken along the line AA of FIG.

FIG. 3 is a vertical cross-sectional view showing a vibration damping structure of a conventional diaphragm joint.

FIG. 4 is a partial perspective view showing an example of the shape of the elastic arm of FIG.

[Explanation of symbols]

 11 Friction Cylinder 12 Centrifugal Weight 13 Centrifugal Weight Holder 14 Elongated Bolt 15 Sleeve 17 Rubber Liner 18 Bolt Holder

 ─────────────────────────────────────────────────── ─── Continuation of the front page (72) Inventor Taku Ichiyanagi 2-8-25, Niihama, Arai-cho, Takasago-shi, Hyogo Takahishi Engineering Co., Ltd.

Claims (2)

[Claims] 1. In a vibration damping structure of a diaphragm joint in which a rotation speed changes in a wide range, a friction cylinder fixed to a diaphragm mounting flange, a centrifugal weight that presses against the friction cylinder by receiving a centrifugal force, and a centrifugal weight of the centrifugal weight. A centrifugal weight holder for guiding, an elongated bolt for holding the centrifugal weight holder, a sleeve which holds one end of the elongated bolt and is integrally formed with the friction cylinder, and a driven shaft which holds the other end of the elongated bolt. Alternatively, a vibration suppressing structure for a diaphragm joint is configured by a shaft holder of a drive shaft and a bolt holder formed integrally with the shaft flange. 2. The vibration damping structure for a diaphragm joint according to claim 1, wherein a rubber liner is interposed between the friction cylinder and the sleeve.