JPH08107640A - Rotor of synchronous motor - Google Patents

Abstract

PURPOSE: To obtain a rotor of a synchronous motor which makes it possible to regulate the residual amount of an impregnating agent in individual gaps inside the rotor in a process of impregnation so that it be a desired amount. CONSTITUTION: A rotor 10 is equipped with a plurality of permanent magnets 14 disposed radially around a rotating shaft 12, a plurality of core members 16 holding the permanent magnets 14 in the circumferential direction respectively and provided around the rotating shaft 12 and end plate members 20 disposed at the opposite ends in the axial direction of the core members 16 and fixed to the rotating shaft 12. Each core member 16 is equipped with a plurality of second through holes 30 extending in the axial direction independently of a through hole holding a rod member 26, for the purpose of reducing the inertia of the rotor. Each end plate member 20 is equipped with a plurality of communication holes 32 provided respectively at positions whereat they can overlap the second through holes 30 of each core member 16. The communication holes 32 make the second through holes 30 of each core member 16 communicate with the surrounding air of the rotor 10 so that fluid can flow through.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a rotor of a synchronous motor, and more particularly to a rotary shaft, a plurality of permanent magnets radially arranged around the rotary shaft, and a permanent magnet sandwiched between the permanent magnets in a circumferential direction for rotation. A plurality of core members arranged around the shaft, end plate members arranged at both ends in the axial direction of the core member, fixedly connected to the rotating shaft, and housed in through holes penetrating the core member in the axial direction, A rotor for a synchronous motor, comprising: a rod member fixed to each of the end plate members at both ends; and a core member having a second through hole extending in the axial direction independently of a through hole for accommodating the rod member.

[0002]

2. Description of the Related Art A plurality of permanent magnets arranged radially around a rotary shaft and a plurality of core members arranged around the rotary shaft sandwiching each of the permanent magnets in the circumferential direction. Synchronous motor rotors are known. An annular end plate member fixedly connected to the rotary shaft is arranged at both axial ends of each core member, and a plurality of rod members axially penetrating each core member are provided at each end plate. By fixing to the member, each core member is fixedly supported at a predetermined position in the rotor. Further, each of the permanent magnets can be positioned in the radial direction by, for example, an outer hook and an inner hook protruding from the outer peripheral portion and the inner peripheral portion of the adjacent side surfaces of the rotor core. Such a structure is particularly effective when the core member is composed of a laminated body of a plurality of magnetic thin plates, but can also be adopted when a core member composed of a block body of a magnetic material is used.

The rotor having the above structure is impregnated with an impregnating agent after the members are combined together in order to secure a strong fixing between the plurality of core members and the plurality of permanent magnets. As an example, as shown in FIG. 14, in this impregnation step, the assembled rotor 1 is first immersed in the impregnating agent 3 in the tank 2, and the inside of the tank 2 is evacuated to impregnate all the gaps in the rotor 1. The agent 3 is permeated (FIG. 14 (a)). Then rotor 1
Of the impregnating agent 5 is taken out from the tank 2 and is rotated at a high speed around the rotating shaft 4 to remove the excess impregnating agent 5 (FIG. 14).
(B)). After that, the rotor 1 is placed in a high temperature environment, and the impregnating agent remaining in the inter-rotor gap is thermally cured to firmly fix the members.

In the rotor having such a structure, magnetic flux is applied to each core member as compared with a rotor in which a plurality of permanent magnets forming magnetic poles are attached to the outer peripheral surface of one substantially cylindrical core member. Since the concentration can be concentrated, there is an advantage that the magnetic flux density of the air gap between the stator and the rotor can be expanded, but there is a problem that the assembly strength is slightly inferior and the armature reaction is easily affected. Therefore, in order to reduce the inertia of the rotor and increase the magnetic resistance against armature reaction, each core member is provided with a second through hole that extends in the axial direction independently of the through hole that accommodates the rod member. Has already been proposed (see, for example, Japanese Patent Application Laid-Open No. 4-147509).

[0005]

In a rotor having a second through hole in the core member, the end plate member supports the rod member at a position aligned with the through hole for the rod member provided in each core member. The second through hole is generally closed at both ends by end plate members. Even with such a configuration, the impregnating agent surely permeates into the second through holes by making the inside of the tank a vacuum state in the impregnating step. The impregnating agent that has penetrated into the second through holes is an extra substance that is not essentially involved in the fixation between the members, but if the second through holes are closed by the end plate members at both ends, the next high speed rotation may occur. The excess impregnating agent is not easily removed in the removal step, but remains in the second through hole.

In the next thermosetting step, the viscosity of the impregnating agent temporarily decreases, but the impregnating agent remaining in a relatively large gap such as the second through hole is retained in the second through hole as the viscosity decreases. There is a case where it cannot flow completely, and for example, it may flow out of the rotor from the gap between the core member and the end plate. In particular, if the impregnating agent is hardened in the state of flowing out to the outer peripheral surface of the rotor, it cannot be used as it is because the outer diameter of the rotor increases, and post-processing such as grinding is required. In order to avoid such inconvenience, if the removal amount is increased by increasing the rotation speed of the rotor or the like in the step of removing the excess impregnating agent, there is a risk that even the impregnating agent necessary for fixing the members will be removed. Occurs.

An object of the present invention is to adjust the residual amount of the impregnating agent in the inner clearance of the rotor in the rotor impregnation step to a desired amount in a rotor in which a second through hole is provided in the core member for the purpose of reducing inertia. Therefore, it is an object of the present invention to provide a rotor of a synchronous motor to which excellent mechanical strength is given.

[0008]

In order to solve the above-mentioned problems, the present invention provides a rotating shaft, a plurality of permanent magnets radially arranged around the rotating shaft and magnetized in the circumferential direction, and a permanent magnet. A plurality of core members each sandwiching each of them in the circumferential direction and arranged around the rotary shaft, and forming a magnetic pole of the rotor between adjacent permanent magnets, and arranged at both axial ends of the core member,
The core member includes an end plate member fixedly connected to the rotating shaft, and a rod member housed in a through hole penetrating the core member in the axial direction and fixed to each of the end plate members at both ends. In a rotor of a synchronous motor having a second through hole independently extending in the axial direction, the second through hole of each core member is provided with opening means for communicating the atmosphere around the rotor so that fluid can flow. A rotor for a synchronous motor is provided.

[0009]

With the opening means, the second through hole of each core member is communicated with the atmosphere surrounding the rotor so that the fluid can flow therethrough, so that the second through hole of each core member permeates in the impregnation step of the rotor. At least part of the impregnating agent spontaneously flows out of the rotor through the opening means when the rotor is taken out from the impregnation tank. Further, when the rotor is rotated at a high speed, for example, about the rotation axis in the stage of removing the excess impregnating agent, the impregnating agent remaining in the second through holes of each core member is forcibly discharged to the outside of the rotor through the opening means. At this time, by properly adjusting the rotation speed, it is possible to almost completely discharge the residual impregnating agent in the second through holes without removing even the impregnating agent necessary for fixing between the constituent members of the rotor.

[0010]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS The present invention will be described in more detail based on its embodiments with reference to the accompanying drawings. Throughout the drawings, the same components are denoted by the same reference numerals. 1 to 3 are
1 shows a rotor 10 of a synchronous motor according to a first embodiment of the present invention. The rotor 10 includes a rotary shaft 12, a plurality of (six in the illustrated example) permanent magnets 14 radially arranged around the rotary shaft 12, and the rotary shaft 1 with the permanent magnets 14 sandwiched in the circumferential direction.
2 and a plurality of (six in the illustrated example) core members 16 disposed around the periphery of the two. The permanent magnet 14 has a plate shape with a substantially rectangular cross section that extends in the axial direction over substantially the entire length of the core member 16. The permanent magnets 14 are alternately magnetized in the circumferential direction around the rotary shaft 12, and the core members 16 alternately form the magnetic poles of the rotor 10 between the adjacent permanent magnets 14. Each core member 16 is formed by laminating substantially fan-shaped magnetic thin plates such as silicon steel plates in the axial direction, or is made of a block body of magnetic material having a substantially fan-shaped cross section, and has permanent magnets on each side surface extending in the radial direction. Close to 14. Further, at both ends of the arcuate outer peripheral surface of the core member 16, hooks 1 projecting in the circumferential direction from both side surfaces are provided.
8 is formed, and the permanent magnets 14 are radially positioned by the hooks 18 of the adjacent core members 16.

Annular end plate members 20 are arranged at both axial ends of the permanent magnet 14 and the core member 16, respectively. Each of the end plate members 20 is in contact with both end faces in the axial direction of the permanent magnet 14 and the core member 16 at one end face in the axial direction, and is shrink-fitted to the rotary shaft 10 by a shaft hole 22 provided at the center thereof. Fixed by. Each core member 16 has one through hole 24 penetrating in the axial direction at each substantially central position, and a rod member 26 is inserted into each through hole 24. Both ends of each rod member 26 are fixed to each end plate member 20 by penetrating through the rod holes 28 provided in each end plate member 20 at positions aligned with the respective through holes 24.

In order to reduce the inertia and increase the magnetic resistance to the armature reaction, the rotor 10 has a plurality of first core members 16 extending independently from the through holes 24 for accommodating the rod members 26 in the axial direction. 2 through hole 3
0 is provided for each. The second through holes 30 are a pair of second through holes 30 a having a substantially oval cross section formed near the arc-shaped outer circumferential surface of the core member 16, and a cross section formed near the inner circumferential surface of the core member 16. One second through hole 30 having a substantially triangular shape
b. Any of the second through holes 30a, 30b,
The core members 16 extend linearly in the axial direction without intersecting with each other, and open at both axial end faces of the core member 16.

Each end plate member 20 is the second member of each core member 16.
A plurality of communication holes 32 are provided at positions that can overlap the through holes 30a and 30b. These communication holes 32
Constitutes the opening means of the present invention, and connects the second through holes 30a, 30b of each core member 16 and the atmosphere around the rotor 10 so that the fluid can flow. The communication hole 32 has a size that allows the impregnating agent to easily flow within a range that does not significantly reduce the rigidity of the end plate member 20. The end plate member 2
Zero can be formed, for example, by punching and punching from an original plate of a magnetic or non-magnetic metal material or a hard resin material.

According to the rotor 10 having the above structure, in the impregnation step, the second through holes 30a of the core members 16 are
A part of the impregnating agent that has penetrated into 30b spontaneously flows out of the rotor 10 through the communication hole 32 of each end plate member 20 when the rotor 10 is taken out from the impregnation tank. Further, the rotor 10 is attached to the rotary shaft 1 at the stage of removing the excess impregnating agent.
When rotated at a high speed about 2, the impregnating agent remaining in the second through holes 30a and 30b of each core member 16 is removed from each end plate member 20.
It is forcibly discharged to the outside of the rotor 10 through the communication hole 32. At this time, the impregnating agent necessary for fixing between the constituent members of the rotor 10 (for example, between each permanent magnet 14 and each core member 16) is not removed, but the second through holes 30a and 30b.
The rotation speed is properly adjusted so that the remaining impregnating agent in the inside is almost completely discharged. As described above, in the rotor 10, since the amount of the impregnating agent remaining in the individual gaps in the rotor can be adjusted to a desired amount in the impregnating step, it is possible to prevent the unwanted outflow of the excessive impregnating agent in the thermosetting stage, and to prevent the excessive impregnating agent from flowing out after grinding. A rotor having excellent mechanical strength can be easily obtained without adjusting the outer dimensions by processing.

In the step of removing the excess impregnating agent, for example, 100 to 200 rpm is applied to a rotor having an output of 1 to 4 kw equipped with an effective portion (a portion including a core member) having an outer diameter of 80 to 106 mm and a length of 50 to 300 mm. The rotation is performed for 5 to 10 seconds. The posture of the rotor during rotation may be horizontal or upright. In this case, the thickness of the end plate member is, for example, 1.
2 to 1.5 mm, and the diameter of the communication hole is, for example, 2 to 3 mm.

FIG. 4 shows a rotor 34 of a synchronous motor according to a second embodiment of the present invention. The rotor 34 is an enlarged version of the rotor 10 in FIG. 1 in the axial direction, and can be used for a high-output electric motor. Like the rotor 10, the rotor 34 includes six permanent magnets 14 radially arranged around the rotary shaft 12.
And two rotor portions 36, each of which is provided with six core members 16 arranged around the rotary shaft 12 by sandwiching each permanent magnet 14 in the circumferential direction, with a disc member 38 interposed therebetween. It is formed by connecting in the axial direction. At this time, the two rotor portions 36 have the permanent magnets 14 and the core members 16 respectively.
Are connected so that they are aligned with each other without being displaced in the circumferential direction. Alternatively, as is well known, in order to reduce the rotational unevenness when the rotor is operating, the respective permanent magnets 14 and the respective core members 16 are displaced by a predetermined angle in the circumferential direction and both rotor portions 36 are moved.
Can also be connected. Further, in the rotor 34, the end plate member 20 similar to the rotor 10 is arranged on the axial end surface of each rotor portion 36 on the side away from the disc member 38.

As shown in FIG. 5, the disk member 38 is provided with a shaft hole 40 for inserting the rotary shaft 12 at the center thereof, and six rod holes 42 through which the rod member 26 can be inserted are provided in each core member. It is provided at a position aligned with the 16 through holes 24 (FIG. 3). The inner diameter of the shaft hole 40 is set to be substantially equal to or slightly larger than the outer diameter of the rotary shaft 12. As a result, the disk member 38 prevents radial deflection of the elongated rotor 34 that may occur during rotation. When the rotating shaft 10 and the disk member 38 are in contact with each other, or when the rotor portions 36 are connected by shifting a predetermined angle, the disk member 38 is preferably made of a non-magnetic material such as stainless steel.

Further, the disk member 38 is provided with a plurality of communication holes 44 respectively provided at positions which can overlap the second through holes 30a and 30b of each core member 16. These communication holes 44 form the opening means of the present invention, and connect the second through holes 30a and 30b of the core members 16 of both rotor portions 36 to each other so that fluid can flow. The communication hole 44 provided in the disk member 38 promotes the discharge of the impregnating agent that has penetrated into the second through holes 30a and 30b of the core members 16 of both rotor portions 36 from the communication hole 32 of each end plate member 20. To do. The disk member 38 can be formed, for example, by stamping and punching a magnetic or nonmagnetic metal material or a hard resin material original plate.

In the rotor 34 described above, the disk member 38
The communication hole 44 may be omitted. In addition, each core member 16
The communication hole 44 corresponding to the second through hole 30a is formed in a notch shape (see FIG. 8) opening on the outer peripheral surface of the disk member 38 to discharge the impregnating agent from the area of the disk member 38. Can also be possible. In that case, the communication hole 32 of the end plate member 20 corresponding to the second through hole 30a can be omitted.

The rotor of the synchronous motor according to the present invention can have various sizes and shapes other than the above. For example, the rotor 46 shown in FIGS. 6 to 9 is a modified example of the rotor 34 of FIG. 4, and includes an end plate member 48 and a disk member 50 having different shapes from the end plate member 20 and the disk member 38. The shape of the second through hole 30b of each core member 16 is also slightly modified. The other configuration of the rotor 46 is substantially the same as that of the rotor 34, and thus the description thereof is omitted.

The end plate member 48 is provided on each of the outer peripheral surface and the inner peripheral surface defining the shaft hole 52 at a position where it can be at least partially overlapped with the second through holes 30a, 30b of each core member 16. It is provided with a plurality of communication notches 54 provided. Similarly, the disc member 50 is provided on each of the outer peripheral surface and the inner peripheral surface that defines the shaft hole 56 at a plurality of positions that can be superposed on the second through holes 30a and 30b of the core members 16. A communication cutout 58 is provided. These communicating notches 54 and 58 form the opening means of the present invention, and each core member 1
The second through holes 30a, 30b of No. 6 and the atmosphere around the rotor 46 are connected to each other so that the fluid can flow.

In the rotor 46 described above, the communicating cutouts 5 are formed on the outer peripheral surface and the inner peripheral surface of the end plate member 48 and the disk member 50.
Since 4, 58 are arranged, the end plate member 48 and the disk member 5
In the pressing step for forming 0, the communication notches 54 and 58 can be formed at the same time when the contours of the outer peripheral surface and the inner peripheral surface are formed by punching. The rotor 34 of FIG. 4 requires a dedicated punch and die for forming the communication holes 32 and 44 in the end plate member 20 and the disc member 38, whereas the rotor 46 requires the end plate member 48 and the circle. Since the plate member 50 has a simple mold, the manufacturing cost can be reduced.

The rotor 60 shown in FIGS.
Is another modified example of the rotor 34, and further includes an end plate member 62 and a disk member 64 having different shapes from the end plate member 20 and the disk member 38. Further, each core member 16 includes an additional second through hole 30c extending substantially parallel to the second through hole 30a. The configuration of the rotor 60 other than that is substantially the same as that of the rotor 34, and thus the description thereof is omitted.

The end plate member 62 has an outer diameter smaller than the maximum outer diameter of the effective portion (the portion including the core member 16) of the rotor 60, whereby the second through hole 30a of each core member 16, 30c partially opens outside the outer peripheral surface of the end plate member 62. Further, the end plate member 62 includes a plurality of communication notches 68 arranged along the inner peripheral surface defining the shaft hole 66. The communication cutout 68 is formed in the core member 16 as illustrated.
The second through hole 30b does not have to overlap.

The disc member 64 has an outer diameter smaller than the maximum outer diameter of the effective portion of the rotor 60 and an inner diameter larger than the minimum inner diameter of the effective portion of the rotor 60. Thereby, the second through holes 30a, 30c of each core member 16 are formed.
Partially open outside the outer peripheral surface of the disk member 64, and the second through holes 30b of each core member 16 partially open inside the inner peripheral surface of the disk member 64 defining the axial hole 70. To do.

Thus, in the rotor 60, the end plate member 62
Outer diameter and communication notch 68 of small size, and disk member 6
The small outer diameter and the large inner diameter of 4 constitute the opening means of the present invention, and the second through holes 30a, 30 of each core member 16 are formed.
b and 30c are communicated with the atmosphere around the rotor 60 so that the fluid can flow. With such a configuration, the molds of the end plate member 62 and the disk member 64 can be further simplified, which greatly contributes to the reduction of manufacturing cost.

Although the preferred embodiments of the present invention have been described above, the present invention is not limited to the description of the embodiments, particularly regarding the opening means, and various changes and modifications can be made. For example, the end plate member and the disc member can have various shapes and combinations other than the above. When the core member is made of a laminated body of thin plate cores, the second core member
Each core member can also be formed by forming the second through-hole element of the thin plate core forming the through hole as a notch opening to the outer peripheral surface and the inner peripheral surface of only one thin plate core in the laminated core member. The second through hole can be communicated with the atmosphere surrounding the rotor so that the fluid can flow therethrough.

[0028]

As is apparent from the above description, according to the present invention, in a rotor in which a second through hole is provided in a core member for the purpose of reducing inertia, etc., the second through hole of each core member and ambient air around the rotor are provided. By providing the opening means for communicating with and so that the fluid can flow, since the impregnating agent that has penetrated into the second through holes of each core member in the impregnation step of the rotor can be easily discharged to the outside of the rotor, In the step of removing the excess impregnating agent in the impregnating step, the impregnating agent remaining in the second through hole can be almost completely removed without removing even the impregnating agent necessary for fixing between the constituent members of the rotor. Therefore, according to the present invention, there is provided a rotor for a synchronous motor, which can be manufactured inexpensively without performing dimension adjustment by post-processing such as grinding, and has excellent mechanical strength and operational reliability.

[Brief description of drawings]

FIG. 1 is a partially cutaway perspective view of a rotor according to a first embodiment of the present invention, in which a second through hole and a communication hole are indicated by broken lines.

2 is a cross-sectional view taken along the line II-II of FIG. 1, showing the permanent magnet and the core member in broken lines.

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

FIG. 4 is a partially cutaway perspective view of a rotor according to a second embodiment of the present invention, in which a second through hole and a communication hole are indicated by broken lines.

5 is a cross-sectional view taken along the line VV of FIG. 4, showing the permanent magnet and the core member in broken lines.

6 is a perspective view of a modified example of the rotor of FIG. 4, in which a second through hole is indicated by a broken line.

7 is a cross-sectional view taken along the line VII-VII of FIG. 6, showing the permanent magnet and the core member in broken lines.

8 is a cross-sectional view taken along the line VIII-VIII of FIG. 6, showing the permanent magnet and the core member in broken lines.

9 is a cross-sectional view taken along the line IX-IX in FIG.

FIG. 10 is a perspective view of another modification of the rotor of FIG.

11 is a cross-sectional view taken along the line XI-XI of FIG. 10, showing the permanent magnet and the core member in broken lines.

12 is a cross-sectional view taken along the line XII-XII of FIG. 10, showing the permanent magnet and the core member in broken lines.

13 is a cross-sectional view taken along the line XIII-XIII in FIG.

FIG. 14 is a diagram showing a rotor impregnation step, and schematically shows (a) an impregnating agent dipping step and (b) an excessive impregnating agent removing step.

[Explanation of symbols]

 12 ... Rotating shaft 14 ... Permanent magnet 16 ... Core member 20, 48, 62 ... End plate member 26 ... Rod member 30a, 30b, 30c ... Second through hole 32, 44 ... Communication hole 38, 50, 64 ... Disc member 54, 58, 68 ... Communication notches

Claims (1)

[Claims] 1. A rotary shaft, a plurality of permanent magnets radially arranged around the rotary shaft and magnetized in the circumferential direction, and a circumference of the rotary shaft by sandwiching each of the permanent magnets in the circumferential direction. A plurality of core members each of which forms a magnetic pole of the rotor between adjacent permanent magnets, and end plate members which are arranged at both axial ends of the core member and are fixedly connected to the rotating shaft, A rod member that is housed in a through hole that penetrates the core member in the axial direction and is fixed to each of the end plate members at both ends, and the core member extends in the axial direction independently of the through hole. Second
A rotor of a synchronous motor having a through hole, comprising: an opening means for communicating the second through hole of each of the core members and an atmosphere around the rotor so that a fluid can flow therethrough. Rotor.