JPH0676699U - Anti-vibration device for rotor - Google Patents

Abstract

(57) [Summary] [Purpose] The rotor is assembled without restrictions on the inner diameter of the rotor parts, and the fastening bolts are restricted. [Structure] Rotor parts 1, 2 and 3 are sequentially fitted and joined to the outside of a fastening bolt 4 having one end fixed, and the fastening bolt 4
When fastening with, the vibration preventing metal fitting 10 having the multiple crack structure is press-fitted into the gap between the fastening bolt 4 and the rotor component 2 on the outside thereof. The vibration prevention metal fitting 10 has a small diameter portion 10a press-fitted inside the rotor component 2 and a large diameter portion 10b having a diameter larger than the small diameter portion 10a. The large-diameter portion 10b is fixed by the rotor parts 2 and 3, and the fastening bolt 4 is restrained to suppress vibration. Since the vibration prevention fitting 10 can be mounted from the side, the rotor component 1 can have a small inner diameter.

Description

[Detailed description of the device]

[0001]

[Industrial applications]

 The present invention relates to an apparatus for suppressing vibration of a fastening bolt during rotation and preventing the rotor from vibrating in a rotor in which a plurality of rotor parts are integrally joined to each other and fastened with a fastening bolt. It is a thing.

[0002]

[Prior art]

 When a plurality of rotor parts are joined together to form a rotor, the rotor parts are joined together in a rotating direction by means of a Kabic coupling, such as gear meshing, and then the fastening bolts passed inside. At this time, the rotor is fastened in the axial direction to form a double structure rotor.

FIG. 4 shows, as an example, an electric fan 1 of a compressor as a rotor component and turbine impellers 2 and 3 of a turbine as rotor components arranged side by side in the axial direction and joined together, and these bolts are used for fastening. 4 shows a rotor which is fastened in the axial direction. In the case of the conventional rotor shown in FIG. 4, the fan 4 of the compressor and the turbine are attached to the fastening bolts 4 in which the screw portion 4a on one end side is screwed and fixed to the axial center position of the compressor side bearing portion 5. The impellers 2 and 3 and the turbine side bearing 6 are sequentially inserted and arranged, and the compressor side bearing 5 and the fan 1, the fan 1 and the impeller 2, the impellers 2 and 3, and the impeller 3 The turbine-side bearing portion 6 is sequentially meshed and joined by the curvic coupling portion 7, and finally, the shaft end nut 8 is screwed onto the threaded portion 4b on the other end side of the fastening bolt 4 to make several tons. I try to tighten it with force.

As described above, when a plurality of rotor parts are joined at the curvic coupling portion 7 and fastened by the fastening bolts 4, the rotor is rotated at a high speed. As shown in FIG. Since there is a gap between the wheel 1 and the impellers 2 and 3, when the rotation speed of the rotor reaches the vicinity of the natural frequency of the fastening bolt 4, the fastening bolt 4 vibrates. When the fastening bolt 4 vibrates, the rotor vibrates.

Therefore, conventionally, as shown in FIG. 4, a protrusion 9 is integrally formed at or near the antinode of the vibration mode of the fastening bolt 4, and the protrusion 9 is brought into contact with the inner surface of the impeller 2. Thus, the fastening bolts 4 are constrained and vibrations of the fastening bolts 4 are prevented.

[0006]

[Problems to be solved by the device]

 However, in the conventional method in which the projection 9 is formed at an intermediate position of the fastening bolt 4 to restrain the fastening bolt 4, the clearance between the fan wheel 1 of the compressor and the fastening bolt 4 is considered in terms of strength. It is better to reduce the inner diameter of the fan 1 in order to reduce the inner diameter of the fan 1. However, if the inner diameter of the fan 1 is reduced, the inner diameter of the fan 1 will hit the projection 9 when the fan 1 is fitted along the fastening bolt 4, The rotor cannot be assembled, the inner diameter of the fan wheel 1 cannot be reduced due to the above, and strength problems remain. The fan wheel 1 and the impellers 2 and 3 as rotor parts outside the fastening bolts 4 cannot be assembled. Since the centrifugal force during rotation of the rotor causes large elongation, the gap between the rotor component and the protrusion 9 of the fastening bolt 4 becomes large when the rotor rotates. The fastening bolt 4 is used for fastening the rotor component. Because several tons of axial force is applied Or provided with projections 9, when provided with a groove serving as a cooling air passage projections 9 parts, here stress is concentrated, the life of the fastening bolt is short, there are problems like.

Therefore, the present invention is intended to enable the rotor to be assembled and to prevent the vibration of the fastening bolt even if the gap between the rotor component and the fastening bolt is reduced.

[0008]

[Means for Solving the Problems]

 In order to solve the above-mentioned problems, the present invention joins a plurality of rotor parts arranged on the outer side of a fastening bolt so as to be integrated with each other in the rotation direction, and fastens each rotor part with the fastening bolt. The outer part of the rotor, which has a multi-split structure and can be press-fitted into the gap between the rotor parts outside the intermediate position of the fastening bolt, at or near the antinode of the vibration mode, which is the intermediate position of the fastening bolt. A vibration prevention metal fitting having a small diameter portion and a large diameter portion that is larger in diameter than the small diameter portion so that it can be engaged with a rotor component is mounted, and the fastening bolt is restrained by the vibration prevention metal fitting. The structure is designed to prevent rotor vibration.

Further, the vibration prevention fitting is provided with a cooling air passage.

[0010]

[Action]

 Since the anti-vibration metal fitting is attached to the middle position of the fastening bolt to restrain the fastening bolt, the vibration of the fastening bolt can be prevented. The rotor component that does not engage with the vibration prevention fitting can have a smaller inner diameter and a smaller clearance between the rotor component and the fastening bolt, so the strength of the rotor component can be increased.

[0011]

【Example】

 An embodiment of the present invention will be described below with reference to the drawings.

FIGS. 1 to 3 show an embodiment of the present invention. Like the case shown in FIG. 4, a fan fan 1 of a compressor and an impeller 2 of a turbine 2 are used as rotor parts constituting a rotor. An example is shown in which 3 is joined in the axial direction and is fastened in the axial direction by fastening bolts 4. That is, the fan 1 of the compressor, the impellers 2 and 3 of the turbine, and the turbine of the turbine are provided outside the fastening bolts 4 that are fixed by screwing the threaded portion 4a on the one end side to the shaft center portion of the bearing 5 on the compressor side. The side bearing portions 6 are fitted in order and joined so as to be united in the direction of rotation by the curvic coupling portion 7, respectively, and the shaft end nut 8 is screwed into the screw portion 4b on the other end side of the fastening bolt 4. In the structure configured to be fastened, in order to restrain the antinode of the vibration mode of the fastening bolt 4 or its vicinity when the rotor rotates, the antivibration metal fitting 10 having a multiple crack (two cracks in the embodiment) structure is provided. It is mounted at an intermediate position of the fastening bolt 4, and the vibration prevention metal fitting 10 is fixed by the impellers 2 and 3 to restrain the fastening bolt 4 and prevent vibration.

The vibration prevention fitting 10 has an inner diameter substantially equal to the outer diameter of the fastening bolt 4 so that it can be fitted to the outer side of the fastening bolt 4, and has the inner diameter of the impeller 2 at the outer peripheral portion. A small-diameter portion 10a having a combined outer diameter and a large-diameter portion 10b having a larger diameter than the small-diameter portion 10a are sandwiched between the impellers 2 and 3 so as to be engaged and prevented from coming off. In addition, the inner diameter of the large diameter portion 10b is set to be slightly larger than the outer diameter of the fastening bolt 4, and further, a passage 11 for flowing cooling air is provided in the inner diameter portion over the entire length in the axial direction. One end side is partially notched to have a protrusion 12 so that an air passage is formed.

When the fastening bolts 4 of the rotor are restrained by using the vibration prevention fittings 10 to prevent vibration, the fan wheel 1 and the impeller 2 as rotor parts are provided outside the fastening bolts 4. Is fitted from the other end side of the fastening bolt 4, and the both are joined by the curvic coupling portion 7, and then the vibration-preventing metal fitting 10 which is a two-break type is fitted from the lateral direction of the fastening bolt 4. The small diameter portion 10a is attached and moved along the fastening bolt 4 in the axial direction, and the small diameter portion 10a is press-fitted into the gap between the impeller 2 and the fastening bolt 4. Next, the impeller 3 is fitted on the outside of the fastening bolt 4 to be joined to the impeller 2 at the curvic coupling portion 7, and the large diameter portion 10b of the vibration prevention metal fitting 10 is formed between the inner diameter portions of both impellers 2 and 3. So that the turbine side bearing portion 6 is fitted and the fastening bolt 4 is fastened with the shaft end nut 8 with an axial force of several tons, so that the vibration preventing metal fitting 10 is engaged with the impellers 2 and 3. To fix it.

Normally, the fastening bolt 4 of the rotor resonates when the rotation speed of the rotor reaches the vicinity of the natural frequency of the fastening bolt 4, but in the present invention, the vibration prevention tool 10 is used. Restrains the vibration of the fastening bolt 4, so that it acts to increase the apparent natural frequency of the fastening bolt 4, and the vibration can be prevented.

In the present invention, the multi-breaking type vibration prevention metal fitting 10 is attached to the fastening bolt 4 so that it can be inserted and removed without providing the shaft portion of the fastening bolt 4 with a projection as in the conventional method. Therefore, it is not necessary to increase the inner diameter of the fan wheel 1 of the compressor as the rotor part, and the gap between the fan wheel 1 and the fastening bolt 4 can be reduced, so that the strength can be increased. it can.

Note that the present invention is not limited to the above-described embodiment, and the fan fan 1 of the compressor and the impellers 2 and 3 of the turbine are illustrated as the rotor parts, but other parts may be used as the rotor parts. Although the cooling air passage 11 is provided along the inner peripheral surface of the vibration prevention metal fitting 10, it may be provided at the outer peripheral portion. In this case, the size of the passage changes depending on the amount of air flow. Needless to say, various changes can be made without departing from the scope of the present invention.

[0018]

[Effect of device]

 As described above, according to the vibration preventing device for a rotor of the present invention, in the rotor having the double structure in which a plurality of rotor parts are joined by the curvic coupling and fastened by the fastening bolts, the fastening bolts are In order to prevent the rotor from vibrating due to vibration, a multi-breaking anti-vibration metal fitting is detachably attached to the fastening bolt, and the anti-vibration metal fitting is engaged by engaging the anti-vibration metal fitting with the outer rotor component. Since the fastening bolts are restrained via the fastening bolts, the fastening bolts are restrained when the rotor rotates and vibrations of the rotor can be prevented without vibrating. Therefore, it is not necessary to increase the inner diameter of the other rotor parts because the fastening bolts themselves can be free from processing such as protrusions, and there are few restrictions on the inner diameter shape of the rotor parts. As a result, the gap between the rotor part and the fastening bolt can be reduced, which is advantageous in terms of strength. Furthermore, the fastening bolt itself can be free from processing such as protrusions, and the vibration-preventing metal fitting can be used for cooling. By providing the air passage, stress can be prevented from concentrating on the fastening bolt, and the life of the fastening bolt can be extended.

[Brief description of drawings]

FIG. 1 is a cross-sectional view showing an embodiment of an anti-vibration device for a rotor according to the present invention.

FIG. 2 is an enlarged view of a portion II in FIG.

3 is a view taken along the line III-III in FIG.

FIG. 4 is a cross-sectional view showing an example of a conventional rotor vibration prevention device.

[Explanation of symbols]

 1 Fan (rotor part) 2, 3 Impeller (rotor part) 4 Fastening bolt 10 Vibration prevention metal fitting 10a Small diameter part 10b Large diameter part

 ─────────────────────────────────────────────────── ─── Continuation of front page (72) Inventor Masaru Sakaki, 1-1-15 Toyosu, Koto-ku, Tokyo Ishikawajima Harima Heavy Industries Ltd. Technical Research Institute

Claims (1)

[Scope of utility model registration request] 1. A fastening method for a rotor, wherein a plurality of rotor parts arranged outside of fastening bolts are joined to each other so as to be integrated in a rotation direction, and each rotor component is fastened by the fastening bolts. A small-diameter portion having a multi-split structure at the intermediate position of the bolt and having an outer diameter that can be press-fitted into the gap between the rotor component and the outside of the intermediate position of the fastening bolt, and the diameter from the small-diameter portion are made large to engage the rotor component. An anti-vibration device for a rotor, characterized in that an anti-vibration metal fitting having a large diameter portion adapted to be fitted is attached, and the anti-vibration metal fitting restrains a fastening bolt to prevent vibration of the rotor.