JP3302705B2 - Superconducting rotating electric machine rotor - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION [Object of the Invention]

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a rotor of a superconducting generator, for example, and more particularly to a rotor of a superconducting rotating electric machine having an improved support structure for a low-temperature rotor.

[0002]

2. Description of the Related Art Conventionally, there is a rotor of this type having a structure as shown in FIG. In FIG. 7, reference numeral 1 denotes a normal temperature damper which forms an outer cylinder of a rotor and has a damper function also serving as a vacuum vessel. Rotary shafts 2 are connected to both ends of the normal temperature damper 1, and each is supported by a bearing 3. ing. In this case, one rotation shaft 2 is provided with a refrigerant supply hole 2 a for supplying a refrigerant such as liquid helium into the normal temperature rotor 1.

Reference numeral 4 denotes a coil mounting shaft provided coaxially inside the normal temperature rotor 1 and having a center hole 4a for storing a refrigerant therein, and a plurality of slots provided on an outer peripheral portion of the coil mounting shaft. The superconducting field coil 5 is housed in the housing.

Further, torque tubes 6a and 6b forming thin-walled cylinders are provided on outer peripheral surfaces of both ends of the coil mounting shaft 4 in order to reduce heat penetration into the coil mounting shaft. Flexiblely connected to the inner surface of the normal temperature rotor 1 via a flexible support 7,
The other torque tube 6 b is attached to the inner surface of the end plate of the normal temperature rotor 1. Further, both torque tubes 6a, 6
A radiation shield 8 for reducing radiant heat to the coil mounting shaft 4 is attached to the outer peripheral surface of the coil b so as to surround the coil mounting shaft 4.

[0005] On the other hand, reference numeral 9 denotes a refrigerant transfer device attached to the other shaft end of the room temperature damper 1. This refrigerant transfer device 9 supplies or recovers refrigerant to the center hole 4a of the coil mounting shaft 4 through the refrigerant supply hole 2a. Things.

The superconducting rotor having the above configuration cools the superconducting field coil 5 to a predetermined temperature to reduce the electric resistance of the superconducting field coil 5 to zero and generate a strong magnetic field. Generate power.

Here, when one of the torque tubes 6a is mounted on the room temperature damper 1, the main purpose of providing the flexible support 7 is to cool the low-temperature rotor composed of the coil mounting shaft 4 and the torque tube 6a to a low temperature by the refrigerant. The purpose is to absorb the heat absorption deformation caused by the deformation by the deformation of the flexible support so as not to generate unnecessary stress between the flexible support and the normal temperature rotor.

FIG. 8 is a view of the conventionally used flexible support 7 viewed from the axial direction of the rotor. As shown in FIG. 8, the flexible support 7 has a spoke shape in which a part of a disk is cut away, and its outer diameter is connected to the room temperature damper 1 and its inner diameter is connected to the torque tube 6a by a reamer bolt 10. . Although not shown, a diaphragm-shaped disk without a notch is also used as a flexible support, but also in this case, a reamer bolt is used for the joint.

[0009]

When the size of the superconducting generator is increased, the length of the rotor shaft is increased, but the amount of heat shrinkage of the low-temperature rotor is increased and the amount of deformation of the flexible support is also increased. For this reason, the thickness of the diaphragm-shaped or spoke-shaped disks has been reduced due to the strength requirement of the flexible support, and a structure in which a plurality of disks are stacked has been adopted.

However, in such a structure, when a reamer bolt is used for connection with a normal temperature rotor or a low temperature rotor, the dimensional accuracy of the reamer hole drilling of a multilayer laminated plate is inferior to that of a single plate. Also, the reamer bolt itself requires a gap for assembly at least. As a result, there is a concern that minute backlash may occur between the normal temperature rotor and the low temperature rotor, resulting in deterioration or fluctuation of the vibration characteristics of the rotor.

An object of the present invention is to provide a rotor of a superconducting rotary electric machine which can securely connect a room-temperature rotor and a low-temperature rotor without play even in a flexible support having a multilayered structure for supporting a torque tube. With the goal. [Configuration of the Invention]

[0012]

SUMMARY OF THE INVENTION In order to achieve the above object, the present invention provides a low-temperature rotor having a coil mounting shaft containing a superconducting coil and having torque tubes at both ends, inside a normal-temperature rotor. At least one end of the low-temperature rotor has a disc-shaped diaphragm shape with respect to the normal-temperature rotor, or a flexible support formed by cutting a part of the disc into a spoke shape to have the outer diameter side and the inner diameter side correspond to the normal-temperature rotor and the low-temperature rotor, respectively. In the rotor of the superconducting rotary electric machine formed by coupling , the outer diameter side joint between the flexible support and the normal temperature rotor, and the inner diameter side joint between the flexible support and the low temperature rotor are located at positions facing each other, and
A radial dovetail-shaped groove and a projection are provided on the radial- side connecting portion and the inner-diameter-side connecting portion, respectively.

[0013]

In the rotor of the superconducting rotary electric machine having such a configuration, the flexible support is deformed in the axial direction due to thermal contraction of the low-temperature rotor during normal operation, that is, out-of-plane deformation of the disk. Since the magnitude of the out-of-plane deformation during the operation is several times as large as the thickness of the flexible support, it indicates a state called so-called large deformation, whereby a radial tensile stress is generated between the inner circumference and the outer circumference. However, at the joints where the dovetails are fitted to the low-temperature rotor and the normal-temperature rotor on the inner and outer peripheries of the flexible support, the inclined contact surface of the dove table is reliably contacted by the tensile stress in the radial direction of the disk. The play of the part disappears.

Further, since the flexible support is located between the normal-temperature rotor and the low-temperature rotor, the flexible support itself is also cooled to some extent, causing heat shrinkage. This heat shrinkage also acts in the direction of contacting the dovetails on the inner and outer circumferences of the flexible support. Can be done.

[0015]

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

FIG. 1 is a cross-sectional view of a flexible support portion of a rotor, and FIG. 2 is a cross-sectional view taken along line AA of FIG. 1. The same portions as those of FIG. The description will be omitted, and only different points will be described here. In this embodiment, as shown in FIGS. 1 and 2, a plurality of dovetail-shaped protrusions 11 are formed on the outer peripheral surface of a cylindrical portion formed at the end of one torque tube 6 a and the inner peripheral surface of the normal temperature damper 1. 12 are provided in correspondence with each other. A flexible support 7 for flexibly mounting the torque tube 6a to the room temperature damper 1 is formed by laminating spoke-shaped thin discs, and has a dovetail-shaped protrusion 11 on its inner and outer peripheral portions. 12 are provided with dovetail-shaped grooves 13 and 14, respectively.

To assemble the flexible support 7,
The protrusion 11 on the outer peripheral surface of the cylindrical portion of the torque tube 6a is fitted into the groove 13 on the inner peripheral portion of the flexible support 7, and the protrusion 12 on the inner peripheral surface of the room temperature damper 1 is fitted into the groove 14 on the outer peripheral portion of the flexible support 7. , Flexible support 7
The inner peripheral portion and the outer peripheral portion are connected by tightening with a tightening bolt 16. In this case, when tightening the inner peripheral portion of the flexible support 7, a pressing plate 15 for applying a load evenly is fixed by a fixing bolt 16. Further, as shown in FIG. 3, the dovetail portions, which are the respective connecting portions of the outer peripheral portion of the flexible support 7, have a gap 17 between the dovetail groove 14 and the dovetail protrusion 12 in any direction. The gap 17 allows the flexible support to be easily assembled.

In the rotor having such a configuration, when the rotor is in the stopped state, the flexible support 7 is not subjected to an axial load as shown in FIG. 1, so that the thin plate constituting the flexible support 7 is bent. Absent. on the other hand,
In the operating state, the flexible support 7 is deformed in the axial direction by the heat shrinkage of the low-temperature rotor as shown in FIG. Flexible support 7 subjected to such deformation
Generates tensile forces in the radial direction with respect to the inner diameter portion and the outer diameter portion, respectively.

FIG. 5 shows the fitting relationship of the dove table section in this state. That is, in FIG. 5, for example, if the dovetail groove provided on the outer peripheral portion of the flexible support 7 is pulled toward the inner peripheral side by deformation, as a result, if the gap 17 at the time of assembly shown in FIG. , The gap becomes zero at the dovetail shoulder 18, leading to a contact condition where the two are subjected to compressive stress at the contact. In this case, although not shown, the dovetail groove 13 provided on the inner peripheral surface of the flexible support 7 is provided.
Is pulled to the outer peripheral side by the deformation, and is brought into contact with the dovetail projection 11 on the torque tube side.

Further, since the flexible support 7 exists between the normal temperature rotor and the low temperature rotor, the flexible support itself is cooled while having a certain temperature gradient.
Thermal shrinkage also occurs in the radial direction, making the inner and outer dovetails more in contact.

The tightening bolts 16 in FIG. 1 are for tightening the flexible support 7 in the laminating direction, and do not need to be used for positioning, torque transmission, and load transmission unlike the prior art. Need not be a reambolt. FIG. 6 is a sectional view similar to FIG. 2 showing another embodiment of the present invention.

In this embodiment, as shown in FIG. 6, dovetail grooves 13-1 and 14-1 are provided on the room temperature damper 1 side and the torque tube 6a side, and the dovetail protrusions 11-1 and 12-1 are provided on the flexible support 7 side. Is provided. With such a configuration, the same operation and effect as those of the above-described embodiment can be obtained. Also, the inner diameter side of the flexible support 7 may be a dovetail groove, and the outer diameter side may be a dovetail protrusion, or a combination of the opposite.
Further, the configuration of the flexible support may be a single-layer structure or a diaphragm shape.

In the case of a flexible support in which the outer diameter side is connected to a low-temperature rotor and the inner diameter side is connected to a normal-temperature rotor, the effect of heat shrinkage of the flexible support itself acts on the side that loosens the dovetail, but the effect due to out-of-plane deformation does not occur. This embodiment is the same as the above embodiment, and can be applied and implemented in the same manner as described above by appropriately selecting the gap 17.

[0024]

As described above, according to the present invention, dovetail-shaped grooves or projections are provided on the inner and outer peripheral portions of the flexible support and are connected to the room-temperature rotor and the torque tube. On the other hand, during operation, the contact between the dovetail groove and the protrusion is automatically made due to the out-of-plane deformation of the flexible support due to the thermal shrinkage of the low-temperature rotor and the radial thermal shrinkage of the flexible support itself during operation. , The centering of the low temperature rotor with respect to the normal temperature rotor is automatically performed,
Transmission of torque and load between the low-temperature rotor and the normal-temperature rotor can be reliably performed. That is, the characteristics and strength of the joint between the low-temperature rotor and the normal-temperature rotor are stabilized, and the bending and torsional vibration characteristics of the entire rotor are stabilized, so that it is possible to provide a highly reliable rotor for a superconducting rotary electric machine. .

[Brief description of the drawings]

FIG. 1 is a sectional view showing an embodiment of a rotor of a superconducting generator according to the present invention.

FIG. 2 is a sectional view taken along the line AA of FIG. 1;

FIG. 3 is a view showing a fitted state of a dovetail portion in FIG. 2;

FIG. 4 is a view showing a deformed state of the flexible support in the operating state of the embodiment.

FIG. 5 is a view showing a fitting state of a dovetail portion in an operation state of the embodiment.

FIG. 6 is a sectional view similar to FIG. 2, showing another embodiment of the present invention.

FIG. 7 is a sectional view showing a rotor of a conventional superconducting generator.

FIG. 8 is a front view showing the structure of a conventional flexible support.

[Explanation of symbols]

1 ... room temperature damper, 2 ... end shaft, 3 ... bearing, 4 ...
Coil mounting shaft, 5 ... Superconducting field coil, 6a, 6b ...
... torque tube, 7 ... flexible support, 8 ...
... radiation shield, 9 ... refrigerant conveying device, 11, 12 ...
Dovetail protrusion, 13, 14 ... dovetail groove, 15 ...
... holding plate, 16 ... tightening bolt, 17 ... gap,
18 ... Dovetail shoulder.

Claims (1)

(57) [Claims] A low-temperature rotor accommodating a superconducting coil and having a coil mounting shaft having torque tubes at both ends is provided inside a normal-temperature rotor, and at least one end of the low-temperature rotor is disc-shaped with respect to the normal-temperature rotor. In the rotor of the superconducting rotary electric machine, the outer diameter side and the inner diameter side of a flexible support formed in a spoke shape by notching a part of the diaphragm or the disk are respectively connected to the normal temperature rotor and the low temperature rotor. The outer diameter side connecting portion between the rotor and the normal temperature rotor, and the inner diameter side connecting portion between the flexible support and the low temperature rotor
A rotor for a superconducting rotating electrical machine, wherein a radial dovetail-shaped groove and a projection are provided on an outer-diameter side coupling portion and an inner-diameter side coupling portion, respectively.