Emergency cutting method and shaft generator

Abstract

To provide a shaft generator capable of performing emergency cutting in a shorter time than in the related art.SOLUTION: According to another aspect of the present invention, there is provided an emergency cutting method of a rotor core and an intermediate shaft in a shaft generator including a bolt that fastens the rotor core and the intermediate shaft by being fitted into a first bolt hole and a second bolt hole in a state in which the first bolt hole that is provided in a rotor core flange and extends in a shaft direction of the intermediate shaft and the second bolt hole that is provided in the intermediate shaft flange and extends in the shaft direction are overlapped in the shaft direction. In a state in which a shaft movable ring provided between the rotor core and the intermediate shaft is brought into contact with an end portion of the bolt protruding from one of the first bolt hole and the second bolt hole, the ring is moved in a direction in which the bolt is pushed out from the first bolt hole and the second bolt hole by a feed screw mechanism.SELECTED DRAWING: Figure 5

Description

[Technical Field]

[0001] The present invention relates to an emergency disconnection method for a shaft generator used on a ship or the like, and to the shaft generator. [Background technology]

[0002] A shaft generator used on a ship is an electrical device that is attached to a shaft that transmits the rotation of the ship's main engine to the propeller, and converts rotational energy into electrical energy. Here, the structure of a conventional shaft generator used on a ship will be explained with reference to Figure 1. Figure 1 is a side cross-sectional view of a shaft generator.

[0003] The shaft generator has a cylindrical intermediate shaft 1 installed between the shaft on the main engine side and the shaft on the propeller side. This intermediate shaft 1 is arranged on the inner periphery of a cylindrical rotor core 3, and the rotor core 3 is fixed to the intermediate shaft 1 by fastening an intermediate shaft flange 2 protruding from the outer periphery of the intermediate shaft 1 to a rotor core flange 4 protruding from the inner periphery of the rotor core 3 with reamer bolts 5a and nuts 5b (Figure 2). In addition, a permanent magnet 6 is attached to the outer periphery of the rotor core 3.

[0004] A cylindrical stator core 7 is arranged on the outer periphery of the rotor core 3, and the stator core 7 is held by a stator frame 8. The stator core 7 is formed from steel plates stacked in the axial direction (left and right direction in the figure). The stator core 7 is also sandwiched from both axial ends by presser plates 9 arranged on one and the other axial ends, and the stacked steel plates are held in place to prevent displacement.

[0005] Furthermore, the stator core 7 has slots (not shown) that penetrate in the axial direction, and these slots house stator windings 10 made of copper wire. The shaft generator has this structure, and is designed to generate electromotive force by electromagnetic induction between the stator windings 10 and the permanent magnets 6.

[0006] In this type of shaft generator, if a malfunction occurs, it is necessary to urgently disconnect the intermediate shaft 1 and rotor core 3 to prevent the generation of electromotive force (i.e., to prevent the generation of electricity), which is called emergency disconnection. As shown in Figure 2, which is an enlarged view of the fastening portion between the intermediate shaft flange 2 and the rotor core flange 4, during emergency disconnection, the nut 5b must be removed from the reamer bolt 5a, and the reamer bolt 5a must be pulled out from the bolt hole 2a in the intermediate shaft flange 2 and the bolt hole 4a in the rotor core flange 4.

[0007] One method for pulling out the reamer bolt 5a is to use a burner or the like to heat the fastening portion between the intermediate shaft flange 2 and the rotor core flange 4, thereby expanding the bolt holes 2a and 4a through thermal expansion, and then pull out the reamer bolt 5a. Another method is to provide a threaded hole in the head of the reamer bolt 5a (the end opposite the tip), attach an eyebolt to this threaded hole, and pull out the reamer bolt 5a together with the eyebolt. Another known document relating to a method for pulling out a reamer bolt using an eyebolt is Patent Document 1 listed below. [Prior art documents] [Patent documents]

[0008] [Patent Document 1] Japanese Patent Application Laid-Open No. 2014-31872 Summary of the Invention [Problem to be solved by the invention]

[0009] In conventional shaft generators, the intermediate shaft and rotor core are connected by fastening with a reamer bolt, but the above-mentioned extraction method must be used to extract the reamer bolt, and the structure does not allow for easy extraction. Furthermore, conventional shaft generators use an interference fit, in which the cylindrical portion of the reamer bolt is press-fitted with a diameter larger than the bolt hole, or a clearance fit, in which the gap (difference in diameter) between the cylindrical portion of the reamer bolt and the bolt hole is minimized, but in either case it is difficult to extract the reamer bolt easily.

[0010] As described above, in conventional shaft generators, it is difficult to easily remove the reamer bolt, making it difficult to perform emergency cutting in a short time.

[0011] The present invention has been made to solve the above-mentioned problems, and aims to provide an emergency cutting method and a shaft generator that can perform emergency cutting in a shorter time than conventional methods. [Means for solving the problem]

[0012] In order to achieve the above object, the emergency disconnection method of the present invention is an emergency disconnection method for a shaft generator including a cylindrical stator core, a cylindrical rotor core provided on the inner periphery of the stator core, a cylindrical intermediate shaft provided on the inner periphery of the rotor core, a first bolt hole extending in the axial direction of the intermediate shaft provided in a rotor core flange protruding from the inner periphery of the rotor core, and a second bolt hole extending in the axial direction provided in an intermediate shaft flange protruding from the outer periphery of the intermediate shaft, the first bolt hole and the second bolt hole being overlapped in the axial direction, and bolts fastening the rotor core and the intermediate shaft by being inserted into the first bolt hole and the second bolt hole, and the emergency disconnection method includes an emergency disconnection method for a shaft generator including a rotor core and an intermediate shaft, the emergency disconnection method comprising: an emergency disconnection mechanism for an axially movable ring provided between the rotor core and the intermediate shaft, the axially movable ring being brought into contact with an end of the bolt protruding from one of the first bolt hole and the second bolt hole, and the emergency disconnection mechanism for an axially movable ring being moved in a direction pushing the bolt out of the first bolt hole and the second bolt hole, the emergency disconnection method comprising: an emergency disconnection mechanism for an axially movable ring provided between the rotor core and the intermediate shaft, the emergency disconnection mechanism being moved in a direction pushing the bolt out of the first bolt hole and the second bolt hole ...

[0013] Furthermore, a shaft generator according to the present invention includes a cylindrical stator core, a cylindrical rotor core provided on the inner periphery of the stator core, a columnar intermediate shaft provided on the inner periphery of the rotor core, a first bolt hole extending in the axial direction of the intermediate shaft provided in a rotor core flange protruding from the inner periphery of the rotor core, and a second bolt hole extending in the axial direction provided in an intermediate shaft flange protruding from the outer periphery of the intermediate shaft, with the first bolt hole and the second bolt hole being overlapped in the axial direction, bolts fastening the rotor core and the intermediate shaft by being fitted into the first bolt hole and the second bolt hole, a ring provided between the rotor core and the intermediate shaft and movable in the axial direction, and a feed screw mechanism for moving the ring in a direction pushing the bolt out of the first bolt hole and the second bolt hole with the ring in contact with an end of the bolt protruding from one of the first bolt hole and the second bolt hole. Equipped with.

[0014] In the event of an emergency disconnection, the present invention allows the ring, which is in contact with the end of the fastening member, to be moved by a feed screw mechanism in a direction that pushes the bolt out of the first bolt hole and the second bolt hole, thereby releasing the fastening by the bolt. [Effects of the Invention]

[0015] According to the present invention, it is possible to provide an emergency disconnection method and a shaft generator that can perform emergency disconnection in a shorter time than conventional methods. [Brief explanation of the drawings]

[0016] [Figure 1] FIG. 10 is a side cross-sectional view showing an example of the configuration of a conventional shaft generator. [Figure 2] FIG. 10 is an enlarged view showing a fastening portion between an intermediate shaft flange and a rotor core flange in a conventional shaft generator. [Figure 3] 1 is a side cross-sectional view showing an example of the configuration of a shaft generator according to a first embodiment. [Figure 4] 3 is an enlarged view showing a configuration example of a fastening portion between an intermediate shaft flange and a rotor core flange according to the first embodiment. FIG. [Figure 5] FIG. 10 is a diagram illustrating an operation at the time of emergency disconnection according to the first embodiment. [Figure 6] FIG. 10 is a side cross-sectional view showing an example of the configuration of a shaft generator according to a second embodiment. [Figure 7] FIG. 10 is an enlarged view showing a configuration example of a fastening portion between an intermediate shaft flange and a rotor core flange according to a second embodiment. [Figure 8] FIG. 10 is a plan view showing the configuration of a ring according to a second embodiment. [Figure 9] FIG. 10 is a diagram illustrating an operation at the time of emergency disconnection according to the first embodiment. [Figure 10] FIG. 10 is an enlarged view showing a configuration example of a fastening portion between an intermediate shaft flange and a rotor core flange according to another embodiment. DETAILED DESCRIPTION OF THE INVENTION

[0017] Hereinafter, an embodiment of the present invention will be described with reference to the drawings.

[0018] 1. First Embodiment [1-1. Shaft generator configuration] First, a first embodiment of the present invention will be described. Fig. 3 is a side cross-sectional view showing an example of the configuration of a shaft generator 20 according to the first embodiment, and Fig. 4 is an enlarged view of the area around the fastening portion between the intermediate shaft flange 2 and the rotor core flange 4 in Fig. 3.

[0019] First, we will briefly explain the parts of the shaft generator 20 that are the same as in the conventional configuration. The shaft generator 20 is a permanent magnet shaft generator used on ships and the like, and is an electrical device in which the intermediate shaft 11 is attached to a shaft that transmits the rotation of the ship's main engine to the propeller, and converts rotational energy into electrical energy.

[0020] 3, in the shaft generator 20, a cylindrical intermediate shaft 11 is arranged inside a cylindrical rotor core 3, and the rotor core 3 is fixed to the intermediate shaft 11 by fastening a hollow disk-shaped intermediate shaft flange 2 provided so as to protrude from the outer periphery of the intermediate shaft 11 and a hollow disk-shaped rotor core flange 4 provided so as to protrude from the inner periphery of the rotor core 3 with reamer bolts 15a and nuts 5b. In addition, a permanent magnet 6 is attached to the outer periphery of the rotor core 3 so as to be integral with it.

[0021] A cylindrical stator core 7 is arranged on the outer periphery of the rotor core 3, and this stator core 7 is held by a stator frame 8. The stator core 7 is formed from steel plates stacked in the axial direction (left and right direction in the figure). The outer periphery of the stator core 7 is sandwiched from both axial ends by presser plates 9 arranged on one and the other axial ends, thereby holding the stacked steel plates in place. Furthermore, slots (not shown) that pass through in the axial direction are provided on the inner periphery of the stator core 7, and stator windings 10 made of copper wire are housed in these slots.

[0022] Next, we will explain the parts of the configuration of the shaft generator 20 that are different from the conventional ones. As shown in Fig. 4, in the shaft generator 20, the shape of the reamer bolt 15a is different from that of the conventional reamer bolt 5a. Specifically, the reamer bolt 15a has a small diameter portion 15d on a cylindrical portion 15c. This small diameter portion 15d has a diameter that is about half the diameter of the cylindrical portion 15c, and is thinner than the other portions of the cylindrical portion 15c.

[0023] Furthermore, the shaft generator 20 has a hollow disk-shaped ring 22 arranged between the rotor core 3 and the intermediate shaft 11. The ring 22 has a threaded hole 22a on its inner periphery. The intermediate shaft 11 has a threaded portion 11a on its outer periphery. In the shaft generator 20, the threaded portion 11a of the intermediate shaft 11 is screwed into the threaded hole 22a of the ring 22, so that the ring 22 can be moved in the axial direction of the intermediate shaft 11 by rotating it around the intermediate shaft 11. In other words, the threaded hole 22a of the ring 22 and the threaded portion 11a of the intermediate shaft 11 function as a feed screw mechanism for moving the ring 22 in the axial direction.

[0024] The intermediate shaft flange 2 and the rotor core flange 4 are arranged such that the intermediate shaft flange 2 is on the right side (one axial end) in the drawing and the rotor core flange 4 is on the left side (the other axial end) in the drawing, and the axially extending bolt holes 2a provided in the intermediate shaft flange 2 and the axially extending bolt holes 4a provided in the rotor core flange 4 are overlapped so as to be connected in the axial direction. The intermediate shaft flange 2 and the rotor core flange 4 are fastened together with reamer bolts 15a inserted into the bolt holes 2a and 4a and nuts 5b attached to the threaded portions 15e at the tip ends of the reamer bolts 15a. The intermediate shaft flange 2 is provided with a plurality of bolt holes 2a spaced apart in the circumferential direction, and similarly, the rotor core flange 4 is provided with a plurality of bolt holes 4a spaced apart in the circumferential direction. In the shaft generator 20, reamer bolts 15a are inserted into all (or some of) the plurality of bolt holes 2a and 4a.

[0025] Here, reamer bolt 15a is fitted into bolt holes 2a and 4a with threaded portion 15e on the tip side facing the intermediate shaft flange 2 (one axial end) and head portion 15f facing the rotor core flange 4 (the other axial end). Reamer bolt 15a is composed of head portion 15f and a cylindrical portion 15c with a smaller diameter than head portion 15f, and the tip of cylindrical portion 15c forms threaded portion 15e.

[0026] The ring 22 is provided on the right side of the intermediate shaft flange 2 of the intermediate shaft 1 in the drawing (one axial end side), and faces the threaded portion 15e at the tip side of the reamer bolt 15a. Furthermore, a handle 23 is provided on the surface of the ring 22 opposite to the intermediate shaft flange 2 side (one axial end side). In the shaft generator 20, by operating this handle 23 to rotate the ring 22, the ring 22 can be moved in a direction toward the intermediate shaft flange 2 and a direction away from the intermediate shaft flange 2. The shaft generator 20 is configured as described above.

[0027] [1-2. Emergency disconnection behavior] Next, the operation of the shaft generator 20 during emergency disconnection will be described with reference to Figures 5(A) and (B). As shown in Figure 4, the shaft generator 20 is fastened so that the head 15f of the reamer bolt 15a faces the rotor core flange 4, and the threaded portion 15e at the tip end of the reamer bolt 15a and the nut 5b face the intermediate shaft flange 2, with the rotor core flange 4 and the intermediate shaft flange 2 sandwiched between the head 15f of the reamer bolt 15a and the nut 5b.

[0028] In emergency disconnection, first remove the nut 5b from the threaded portion 15e on the tip side of the reamer bolt 15a, as shown in Figure 5(A). At this time, the threaded portion 15e on the tip side of the reamer bolt 15a protrudes from the bolt hole 2a of the intermediate shaft flange 2.

[0029] In this state, the handle 23 of the ring 22 is operated to move the ring 22 in a direction approaching the intermediate shaft flange 2. Then, the surface of the ring 22 on the intermediate shaft flange 2 side comes into contact with the tip of the reamer bolt 15a protruding from the bolt hole 2a of the intermediate shaft flange 2.

[0030] If the handle 23 of the ring 22 is further operated to move the ring 22 closer to the intermediate shaft flange 2, the ring 22 will push the threaded portion 15e at the tip end of the reamer bolt 15a into the bolt hole 2a, and the head 15f of the reamer bolt 15a will be pushed out so as to move away from the bolt hole 4a.

[0031] When the ring 22 is further moved, the small diameter portion 15d of the cylindrical portion 15c of the reamer bolt 15a reaches the boundary between the rotor core flange 4 and the intermediate shaft flange 2, as shown in FIG. 5(B).

[0032] In this state, if the rotor core 3 is fixed and the intermediate shaft 11 is rotated (or the intermediate shaft 11 is fixed and the rotor core 3 is rotated), the small diameter portion 15d of the reamer bolt 15a can be easily twisted off, thereby releasing the fastening between the intermediate shaft 11 and the rotor core 3 and separating them. The operation in the event of an emergency disconnection is as described above.

[0033] Furthermore, for example, a mark may be provided on the tip side of the cylindrical portion 15c of the reamer bolt 15a, so that when this mark reaches the bolt hole 2a of the intermediate shaft flange 2, the small diameter portion 15d of the reamer bolt 15a is positioned at the boundary between the rotor core flange 4 and the intermediate shaft flange 2. In this way, it becomes clear at a glance that the small diameter portion 15d of the reamer bolt 15a has been positioned at the boundary between the rotor core flange 4 and the intermediate shaft flange 2.

[0034] Furthermore, without being limited to this, for example, the position of the small diameter portion 15d may be selected so that when the reamer bolt 15a is pushed out until the ring 22 abuts against the intermediate shaft flange 2, the small diameter portion 15d is positioned at the boundary between the rotor core flange 4 and the intermediate shaft flange 2. In this way, by moving the ring 22 until it abuts against the intermediate shaft flange 2, the small diameter portion 15d of the reamer bolt 15a will be positioned at the boundary between the rotor core flange 4 and the intermediate shaft flange 2.

[0035] [1-3. Summary and Effects] As described above, the shaft generator 20 of the first embodiment includes the cylindrical stator core 7, the cylindrical rotor core 3 provided on the inner circumferential side of the stator core 7, the cylindrical intermediate shaft 11 provided on the inner circumferential side of the rotor core 3, the rotor core flange 4 protruding from the inner circumferential side of the rotor core 3, the intermediate shaft flange 2 protruding from the outer circumferential side of the intermediate shaft 11 and abutting the rotor core flange 4 and the intermediate shaft 11 in the axial direction, the bolt hole 4a which is an example of a first bolt hole provided in the rotor core flange 4 and extending in the axial direction, and the bolt hole 4b which is an example of a second bolt hole provided in the intermediate shaft flange 2 and extending in the axial direction. The rotor core 3 is provided with a reamer bolt 15a which is an example of a bolt that fastens the rotor core 3 and the intermediate shaft 11 by being inserted into the bolt holes 2a and 4a while connecting the rotor core 3 and the intermediate shaft 11 in the axial direction, a ring 22 which is provided between the rotor core 3 and the intermediate shaft 11 and is movable in the axial direction, and a screw hole 22a of the ring 22 and a screw portion 11a of the intermediate shaft 11 which are an example of a feed screw mechanism for moving the ring 22 in the direction of pushing the reamer bolt 15a out of the bolt holes 2a and 4a while the ring 22 is in contact with a screw portion 15e on the tip side of the reamer bolt 15a protruding from the bolt hole 2a.

[0036] In emergency cutting, after removing the nut 5b from the threaded portion 15e on the tip side of the reamer bolt 15a, the ring 22 is brought into contact with the tip of the reamer bolt 15a, and the feed screw mechanism moves the ring 22 in a direction that pushes the reamer bolt 15a out of the bolt holes 2a and 4a.

[0037] At this time, the reamer bolt 15a is pushed out until the small diameter portion 15d of the reamer bolt 15a is positioned at the boundary between the rotor core flange 4 and the intermediate shaft flange 2, and then the intermediate shaft 11 is rotated with the rotor core 3 fixed, thereby easily twisting off the small diameter portion 15d of the reamer bolt 15a, thereby releasing the fastening between the intermediate shaft 11 and the rotor core 3 and separating them.

[0038] In this way, in the shaft generator 20 of the first embodiment, the ring 22 pushes the reamer bolt 15a out of the bolt holes 2a, 4a until the small diameter portion 15d of the reamer bolt 15a is positioned at the boundary between the rotor core flange 4 and the intermediate shaft flange 2, and then the reamer bolt 15a is twisted off to separate the intermediate shaft 11 and the rotor core 3.

[0039] As a result, in the shaft generator 20 of the first embodiment, there is no need to heat the fastening portion between the intermediate shaft flange 2 and the rotor core flange 4 with a burner or the like, there is no need to use eye bolts or the like, and there is no need to completely pull out the reamer bolt 15a from the bolt holes 2a, 4a, so emergency cutting can be performed in a shorter time than in the past.

[0040] 2. Second Embodiment Next, a second embodiment of the present invention will be described. Fig. 6 is a side cross-sectional view showing an example of the configuration of a shaft generator 100 according to the second embodiment, and Fig. 7 is an enlarged view of the fastening portion between the intermediate shaft flange 2 and the rotor core flange 14 in Fig. 6. Here, the parts of the configuration of the shaft generator 100 that differ from the shaft generator 20 of the first embodiment will be described.

[0041] [2-1. Shaft generator configuration] As shown in Fig. 7, in the shaft generator 100, the shape of the rotor core flange 14 is different from that of the rotor core flange 4 of the first embodiment. Specifically, the rotor core flange 14 has a notch 14b formed on the inner circumferential side of the surface opposite the intermediate shaft flange 2 (the other axial end side). This notch 14b is for fitting a ring 21, which will be described later, into the rotor core flange 14, and when the ring 21 is fitted into the notch 14b of the rotor core flange 14, the rotor core flange 14 has approximately the same shape as the rotor core flange 4 as a whole. Furthermore, the rotor core flange 14 has a bolt hole 14a extending in the axial direction formed within the notch 14b (i.e., on the inner circumferential side).

[0042] Furthermore, the shaft generator 100 includes a ring 21 instead of the ring 22 of the first embodiment. Fig. 8 is a plan view of the ring 21 as viewed from the axial direction. As shown in Figs. 6 to 8, the ring 21 is hollow and disc-shaped, and is disposed between the rotor core 3 and the intermediate shaft 11. As shown in Fig. 8, the ring 21 is provided with a plurality of bolt holes 21a spaced apart in the circumferential direction. The ring 21 is also provided with a plurality of screw holes 21b spaced apart in the circumferential direction. The screw holes 21b are provided, for example, between the bolt holes 21a and the bolt holes 21a.

[0043] In the shaft generator 100, the ring 21 is fitted into the notch 14b of the rotor core flange 14, and the bolt holes 2a of the intermediate shaft flange 2, the bolt holes 14a of the rotor core flange 14, and the bolt holes 21a of the ring 21 are connected in the axial direction. Then, the intermediate shaft flange 2 and the rotor core flange 14 are fastened together with the ring 21 by means of reamer bolts 5a fitted into the bolt holes 2a, 14a, and 21a and nuts 5b attached to the threaded portions 5e on the tip ends of the reamer bolts 5a. In other words, the intermediate shaft flange 2 and the rotor core flange 14 are fastened together with the ring 21 sandwiched between the heads 5f of the reamer bolts 5a and the rotor core flange 14. The shaft generator 100 is configured as described above.

[0044] [2-2. Emergency disconnection behavior] Next, the operation of the shaft generator 100 during emergency disconnection will be described with reference to Fig. 9. During emergency disconnection, first, the nut 5b is removed from the threaded portion 5e on the tip side of the reamer bolt 5a.

[0045] In this state, the set screws 101 are screwed into each of the multiple screw holes 21b provided in the ring 21. Note that in FIG. 9, the positions of the screw holes 21b are shifted downward from their actual positions for ease of viewing. Here, because there are no holes on the rotor core flange 14 side facing the screw holes 21b, when the set screws 101 are screwed into the screw holes 21b, the tips of the set screws 101 come into contact with the rotor core flange 14. If the set screws 101 are further screwed in from this state, the ring 21 is pushed in a direction away from the rotor core flange 14. At this time, the heads 5f of the reamer bolts 5a are pushed out by the ring 21, and the reamer bolts 5a are pushed out of the bolt holes 2a and 14a. In other words, the screw holes 21b of the ring 21 and the set screws 101 function as a feed screw mechanism for moving the ring 21 in the axial direction.

[0046] In this way, in the shaft generator 100, by pushing the reamer bolt 5a out of the bolt holes 2a, 14a together with the ring 21, the reamer bolt 5a can finally be pulled out of the bolt holes 2a, 14a, thereby releasing the fastening between the intermediate shaft 1 and the rotor core 3 and separating them. Note that the entire reamer bolt 5a may be pushed out of the bolt holes 2a, 14a together with the ring 21, or after pushing out a portion of the reamer bolt 5a from the bolt holes 2a, 14a, the reamer bolt 5a may be pulled out using a predetermined jig or the like. The operation in the event of an emergency disconnection is as described above.

[0047] [2-3. Summary and Effects] As described above, the shaft generator 100 of the second embodiment includes the cylindrical stator core 7, the cylindrical rotor core 3 provided on the inner circumferential side of the stator core 7, the columnar intermediate shaft 1 provided on the inner circumferential side of the rotor core 3, the rotor core flange 14 protruding from the inner periphery of the rotor core 3, the intermediate shaft flange 2 protruding from the outer periphery of the intermediate shaft 1 and abutting against the rotor core flange 14 in the axial direction, the ring 21 provided between the rotor core 3 and the intermediate shaft 1 and abutting against the rotor core flange 14 on the side opposite to the intermediate shaft flange 2 side, the bolt holes 14a which are an example of first bolt holes provided in the rotor core flange 14 and extending in the axial direction, and the intermediate shaft flange 2. Bolt hole 2a, which is an example of a second bolt hole extending in the axial direction and provided in flange 2, and bolt hole 21a, which is an example of a third bolt hole extending in the axial direction and provided in ring 21, are connected in the axial direction. Reamer bolt 5a, which is an example of a bolt that is inserted into bolt holes 2a, 14a, and 21a to fasten rotor core 3 and intermediate shaft 1, and screw hole 21b of ring 21 and push screw 101, which are an example of a feed screw mechanism for moving ring 21 in a direction away from rotor core flange 14, are provided, and rotor core 3 and intermediate shaft 1 are fastened together with ring 21 sandwiched between head 15f of reamer bolt 5a and rotor core flange 14.

[0048] In the event of emergency cutting, the nut 5b is removed from the threaded portion 5e at the tip end of the reamer bolt 5a, and then the ring 21 is moved in a direction away from the rotor core flange 14 by the feed screw mechanism.

[0049] At this time, the head 5f of the reamer bolt 5a is pushed out by the ring 21, allowing the reamer bolt 5a to be easily pulled out of the bolt holes 2a, 14a, thereby releasing the fastening between the intermediate shaft 1 and the rotor core 3 and separating them.

[0050] By doing this, in the shaft generator 100 of the second embodiment, there is no need to heat the fastening portion between the intermediate shaft flange 2 and the rotor core flange 4 with a burner or the like, and there is also no need to use an eye bolt or the like, so the reamer bolt 5a can be easily pulled out, and emergency cutting can be performed in a shorter time than in the conventional case.

[0051] [3. Other embodiments (modifications)] [3-1. Other embodiment 1] In the first embodiment described above, the reamer bolt 15a is pushed out until the small diameter portion 15d of the reamer bolt 15a is positioned at the boundary between the rotor core flange 4 and the intermediate shaft flange 2, and then the small diameter portion 15d of the reamer bolt 15a is twisted off, thereby separating the intermediate shaft 11 and the rotor core 3.

[0052] Here, for example, as shown in FIG. 10, the reamer bolt 15a may be replaced with a longer reamer bolt 25a, and the reamer bolt 25a may be pushed out by the ring 22 and then pulled out instead of being twisted all the way through.

[0053] In this case, for example, if tip side portion 25g of cylindrical portion 25c of reamer bolt 25a (for example, the portion protruding from bolt hole 2a of intermediate shaft flange 2) is made slightly smaller in diameter than head side portion 25h (for example, the portion that fits within bolt holes 2a and 4a) (specifically, slightly smaller in diameter than bolt hole 4a of rotor core flange 4), reamer bolt 25a can be pushed out and easily pulled out when head side portion 25h comes out of bolt hole 4a of rotor core flange 4. Also, in this case, if threaded portion 25e is provided on the head side of tip side portion 25g, it becomes easier to attach and detach nut 5b.

[0054] [3-2. Other embodiment 2] In the first embodiment described above, the reamer bolt 15a is pushed out of the bolt holes 2a and 4a by the ring 22 to twist off the small diameter portion 15d, and in the second embodiment, the reamer bolt 5a is pushed out of the bolt holes 2a and 14a by the ring 21 to be pulled out.

[0055] However, the present invention is not limited to this, and the first and second embodiments may be combined to push the reamer bolt 15a out of the bolt holes 2a and 14a by the ring 21, thereby twisting off the small diameter portion 15d.

[0056] [3-3. Other embodiment 3] Furthermore, in the first embodiment described above, the intermediate shaft flange 2 and the rotor core flange 4 are arranged so that the intermediate shaft flange 2 is at one axial end and the rotor core flange 4 is at the other axial end, the intermediate shaft flange 2 and the rotor core flange 4 are overlapped in the axial direction, the reamer bolt 15a is inserted into the bolt holes 2a and 4a with the head 15f facing the rotor core flange 4, and the ring 21 is arranged on the intermediate shaft flange 2 side. However, this is not limitative, and the arrangement of the intermediate shaft flange 2 and the rotor core flange 4 may be reversed, or the orientation of the reamer bolt 15a and the arrangement of the ring 21 may be reversed. The same applies to the second embodiment.

[0057] [3-4. Other embodiment 4] Furthermore, in the above-described embodiments, the present invention is applied to the shaft generators 20 and 100, which are permanent magnet shaft generators used on ships and the like. However, the present invention is not limited to this, and may be applied to a shaft generator having a configuration partially different from that of the above-described embodiments, as long as the rotor core is held only by an intermediate shaft and is configured to be separated from the intermediate shaft in the event of an emergency disconnection, etc. For example, the present invention may be applied to a shaft generator in which the intermediate shaft and rotor core are fastened together by a fastening member such as a bolt other than a reamer bolt.

[0058] Furthermore, the present invention is not limited to the above-described embodiments, and the scope of application of the present invention extends to embodiments in which the first and second embodiments are combined with part or all of the other embodiments, or embodiments in which parts are extracted. [Industrial Applicability]

[0059] The present invention can be widely used in permanent magnet shaft generators used on ships and the like, for example. [Explanation of symbols]

[0060] 1...Intermediate shaft, 2...Intermediate shaft flange, 2a, 4a, 14a, 21a...Bolt holes, 3...Rotor core, 4, 14...Rotor core flange, 5a, 15a, 25a...Reamer bolt, 15d...Small diameter portion, 5b...Nut, 6...Permanent magnet, 7...Stator core, 8...Stator frame, 9...Press plate, 10...Stator winding, 20, 100...Shaft generator, 21, 22...Ring, 21b, 22a...Screw holes, 23...Handle, 101...Push screw.

Claims

1. a cylindrical stator core; a cylindrical rotor core provided on the inner periphery of the stator core; a cylindrical intermediate shaft provided on the inner circumferential side of the rotor core; A method for emergency disconnection of a rotor core and an intermediate shaft in a shaft generator, the method comprising: first bolt holes extending in the axial direction of the intermediate shaft and provided in a rotor core flange protruding from an inner periphery of the rotor core; and second bolt holes extending in the axial direction and provided in an intermediate shaft flange protruding from an outer periphery of the intermediate shaft, the first bolt holes and the second bolt holes being overlapped in the axial direction, and bolts fastening the rotor core and the intermediate shaft by being inserted into the first bolt holes and the second bolt holes, a ring that is provided between the rotor core and the intermediate shaft and is movable in the axial direction is brought into contact with an end of the bolt that protrudes from one of the first bolt hole and the second bolt hole, and the ring is moved by a feed screw mechanism in a direction that pushes the bolt out of the first bolt hole and the second bolt hole; An emergency disconnection method characterized by the above.

2. The bolt has a tip end opposite to the head side protruding from one of the first bolt hole and the second bolt hole, and after the nut is removed from the tip end of the bolt, the ring is brought into contact with the tip end of the bolt, and the ring is moved by the feed screw mechanism in a direction that pushes the bolt out of the first bolt hole and the second bolt hole.

2. The emergency disconnection method according to claim 1.

3. the feed screw mechanism is composed of a screw hole provided on the inner periphery of the ring and a screw portion provided on the outer periphery of the intermediate shaft, The ring is movable in the axial direction by threading a threaded portion of the intermediate shaft into a threaded hole of the ring, The ring is rotated around the intermediate shaft to move the bolt in a direction to push it out of the first bolt hole and the second bolt hole.

3. The emergency disconnection method according to claim 2.

4. the rotor core and the intermediate shaft are fastened together in a state in which the ring is sandwiched between the head of the bolt and one of the rotor core flange and the intermediate shaft flange, The bolt has a tip end opposite to the head side protruding from one of the first bolt hole and the second bolt hole, and after the nut is removed from the tip end of the bolt, the ring is moved by the feed screw mechanism in a direction away from one of the rotor core flange and the intermediate shaft flange, thereby pushing the bolt out of the first bolt hole and the second bolt hole.

2. The emergency disconnection method according to claim 1.

5. The feed screw mechanism The ring has a screw hole extending in the axial direction, and a push screw is screwed into the screw hole. The ring is moved in a direction away from one of the rotor core flange and the intermediate shaft flange by rotating the set screw threaded into the screw hole.

5. The emergency disconnection method according to claim 4.

6. The bolt is composed of a head and a cylindrical portion having a diameter smaller than that of the head, and the cylindrical portion is further provided with a small diameter portion that is thinner than other portions, The bolt is pushed out until the small diameter portion of the bolt reaches the boundary between the rotor core flange and the intermediate shaft flange, and then one of the rotor core and the intermediate shaft is fixed and the other is rotated to twist off the small diameter portion.

2. The emergency disconnection method according to claim 1.

7. Cylindrical stator core and a cylindrical rotor core provided on the inner periphery of the stator core; a cylindrical intermediate shaft provided on the inner circumferential side of the rotor core; a first bolt hole extending in the axial direction of the intermediate shaft and provided in a rotor core flange protruding from the inner periphery of the rotor core, and a second bolt hole extending in the axial direction and provided in an intermediate shaft flange protruding from the outer periphery of the intermediate shaft, the first bolt hole and the second bolt hole being overlapped in the axial direction, thereby fastening the rotor core and the intermediate shaft together; a ring disposed between the rotor core and the intermediate shaft and movable in the axial direction; a feed screw mechanism for moving the ring in a direction for pushing the bolt out of the first bolt hole and the second bolt hole while the ring is in contact with the end of the bolt protruding from one of the first bolt hole and the second bolt hole; Equipped with A shaft generator characterized by:

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