JP2022145140A - Rotary electric machine - Google Patents

Abstract

To provide a rotary electric machine having a novel structure improved so as to have more less inconvenience.SOLUTION: A rotary electric machine of an embodiment, comprises: a rotor; a stator; and a plurality of pair of pressing members. The rotor can be rotated around a center of a rotation. The stator includes a plurality of magnetic steel sheets laminated in an axial direction of the center of the rotation, and is arranged so as to face an external peripheral surface of the rotor. The plurality of pair of pressing members are provided to both sides of the axial direction of the stator, hold the plurality of magnetic steel sheets so as to nip them via a binding tool, and are arranged with an interval from each other in a peripheral direction of the center of the rotation. The pair of pressing members include: a first part facing an end surface of the axial direction of the stator; and a second part extending to the side opposite to the stator of the axial direction from the first part.SELECTED DRAWING: Figure 2

Description

An embodiment of the present invention relates to a rotating electric machine.

Conventionally, a stator having a plurality of magnetic steel sheets laminated in an axial direction and arranged to face the outer peripheral surface of a rotor is held in a state in which the magnetic steel sheets are sandwiched from both sides in the axial direction of the stator. A rotary electric machine is known that includes a pair of annular pressing members.

JP 2017-46466 A

In this type of rotating electrical machine, it would be beneficial to have a new and improved design with less inconvenience.

A rotating electric machine according to an embodiment includes a rotor, a stator, and a plurality of pairs of pressing members. The rotor is rotatable around a center of rotation. The stator has a plurality of electromagnetic steel plates laminated in the axial direction of the rotation center, and is arranged to face the outer peripheral surface of the rotor. A plurality of pairs of holding members are provided on both sides of the stator in the axial direction, hold the plurality of electromagnetic steel plates in a state of being sandwiched therebetween via couplings, and are arranged at intervals in the circumferential direction of the rotation center. be done. The pair of pressing members has a first portion facing the axial end face of the stator and a second portion extending from the first portion in the axial direction opposite to the stator.

FIG. 1 is an exemplary and schematic cross-sectional view of a rotating electric machine according to an embodiment. FIG. 2 is an exemplary and schematic front view of the rotating electric machine of the embodiment. FIG. 3 is an exemplary and schematic cross-sectional view of a rotating electric machine of a first modification. FIG. 4 is an exemplary and schematic front view of a rotating electrical machine of a first modification. FIG. 5 is an exemplary and schematic cross-sectional view of a rotating electrical machine of a second modification. FIG. 6 is an exemplary and schematic front view of a rotating electric machine of a second modification. FIG. 7 is an exemplary and schematic cross-sectional view of a rotating electrical machine of a third modification. FIG. 8 is an exemplary and schematic cross-sectional view of a rotating electrical machine of a fourth modification. FIG. 9 is an exemplary and schematic front view of a rotating electric machine of a fourth modification. FIG. 10 is an exemplary and schematic front view of a rotating electrical machine of a fifth modification.

Exemplary embodiments and variations of the invention are disclosed below. The configurations of the embodiments and modifications shown below, and the actions and effects brought about by these configurations, are examples. The present invention can be realized by configurations other than those disclosed in the following embodiments and modifications. Moreover, according to the present invention, at least one of various effects (including derivative effects) obtained by the configuration can be obtained.

Also, the embodiments and variations disclosed below include similar components. Therefore, hereinafter, common reference numerals are given to those similar components, and duplicate descriptions are omitted. In this specification, ordinal numbers are used only to distinguish parts, members, regions, positions, directions, etc., and do not indicate order or priority.

[Embodiment]
FIG. 1 is a schematic cross-sectional view of a rotating electrical machine 1 of the embodiment, and FIG. 2 is a schematic front view of the rotating electrical machine 1. As shown in FIG. A rotating electric machine 1 shown in FIGS. 1 and 2 is configured as a motor mounted on an elevator hoist, and includes a rotor 2, a stator 3, a pair of pressing members 7 described later, and the like.

In the following description, for convenience, the axial direction of the rotation center Ax of the rotary electric machine 1 is simply referred to as the axial direction, the radial direction of the rotation center Ax is simply referred to as the radial direction, and the circumferential direction of the rotation center Ax is simply referred to as the radial direction. It is called circumferential direction. Further, in the drawings, an arrow X indicates one axial direction, an arrow R indicates an outward radial direction, and an arrow C indicates one circumferential direction.

The rotor 2 is positioned radially inward of the stator 3 . The rotor 2 is configured in a cylindrical shape around the center of rotation Ax. The outer peripheral surface 2a of the rotor 2 faces the inner peripheral surface of the stator 3 with a small radial gap therebetween. In other words, the rotor 2 is arranged to face the stator 3 .

The stator 3 has a stator core 4 and coils 5 . The stator core 4 is configured in an annular shape around the rotation center Ax. The stator core 4 is a so-called laminated core configured by laminating a plurality of electromagnetic steel sheets 4a in the axial direction.

The coil 5 is wound around the teeth of the stator core 4 . The stator 3 generates a magnetic field inside the rotary electric machine 1 by energizing the coil 5, and rotates the rotor 2 in the circumferential direction around the rotation center Ax by interacting with the magnetic field.

A pair of pressing members 7 are provided to press the radially outer end of the stator 3 from both sides in the axial direction. The pair of pressing members 7 has a function of preventing the plurality of electromagnetic steel plates 4a from opening, a function of improving the core strength of the stator 3, a function of improving the assembling efficiency of the stator 3, and the like. A plurality of electromagnetic steel plates 4a are held in a state of being sandwiched in the axial direction.

The coupler 8 has a bolt 8a axially passing through the pressing member 7 and the electromagnetic steel plate 4a, and a nut 8b provided with a female thread that meshes with the male thread of the bolt 8a. In the coupler 8, the pressing member 7 and the electromagnetic steel plates 4a are sandwiched between the head of the bolt 8a and the nut 8b, and the male and female screws are fastened to connect the plurality of electromagnetic steel plates 4a into a pair. It is fixed between pressing members 7 .

Here, in the present embodiment, the rotary electric machine 1 is provided with a plurality of pairs of pressing members 7 spaced apart from each other in the circumferential direction. Specifically, in this embodiment, four pairs of pressing members 7 are arranged at equal intervals in the circumferential direction. The number of sets of pressing members 7 is not limited to four, and may be two, three, five or more. It can also be said that the pressing member 7 has a plurality of divided bodies 6 divided in the circumferential direction.

Each pressing member 7 has a first portion 7a and a second portion 7b. The first portion 7a extends along the axial end face 3a of the stator 3 and faces the end face 3a. The first portion 7a supports the radially outer end of the end surface 3a. The first portion 7a is also called a base portion or the like.

The second portion 7b is provided at the radially outer end of the first portion 7a and protrudes from the end in the axial direction opposite to the stator 3 . That is, the second portion 7b extends in a direction away from each other by the pair of pressing members 7. As shown in FIG. The pressing member 7 is formed in a substantially L shape by a first portion 7a and a second portion 7b when viewed perpendicularly to the axial direction (see FIG. 1). The second portion 7b is also referred to as a convex portion, a projecting portion, or the like.

The pressing member 7 is made of non-magnetic metal material such as SUS (stainless steel) or aluminum. When the pressing member 7 is made of SUS material, it becomes a non-magnetic material compared to when it is made of iron, so that magnetic flux leakage to both sides in the axial direction of the stator 3 can be suppressed, and the motor characteristics can be improved. can be planned. In addition, the SUS material is resistant to corrosion and can improve environmental resistance.

Further, when the pressing member 7 is made of aluminum, the thermal conductivity is higher than that of iron, so the thermal conductivity between the pressing member 7 and the stator 3 is improved. ) can be enhanced. In addition, since aluminum has a smaller specific gravity than iron, it is possible to reduce the weight of the pressing member 7 and the rotating electric machine 1 as well.

In the present embodiment, the pressing member 7 has a rectangular shape when viewed from the axial direction (see FIG. 2), but is not limited to this example. It may be configured in a circular arc shape or a fan shape. Also, the shape of the stator 3 is not limited to an annular shape when viewed from the axial direction (see FIG. 2), and may be a polygonal shape such as a square or a hexagon.

As described above, in the present embodiment, the rotary electric machine 1 has the rotor 2 rotatable around the rotation center Ax and the plurality of electromagnetic steel plates 4a laminated in the axial direction of the rotation center Ax. A stator 3 arranged to face the surface 2a, and a plurality of electromagnetic steel plates 4a provided on both sides in the axial direction of the stator 3, and holding a plurality of electromagnetic steel plates 4a in a state of being sandwiched via couplers 8, and mutually circumferentially. a plurality of pairs of pressing members 7 arranged at intervals, the pair of pressing members 7 having a first portion 7a facing the axial end surface 3a of the stator 3 and a stator axially extending from the first portion 7a. and a second portion 7b extending opposite to 3.

According to such a configuration, for example, compared to a conventional structure in which a pair of pressing members 7 are formed in an annular shape, it is possible to reduce the weight of the pressing members 7 and thus the rotating electric machine 1, while reducing the weight of the stator 3 in the axial direction. Since the exposed area of the end face 3a of the stator 3 is increased, the cooling performance (heat radiation performance) of the stator 3 can be further enhanced. Further, by holding the plurality of electromagnetic steel plates 4a via the coupler 8, welding is eliminated, iron loss can be reduced, and motor characteristics can be improved.

Further, since the surface area of the pressing member 7 is increased by the first portion 7a and the second portion 7b, heat dissipation due to heat exchange between the pressing member 7 and the air flow is improved, and cooling of the stator 3 is further enhanced. can. In addition, since the pressing member 7 has an increased section modulus due to the first portion 7a and the second portion 7b, the rigidity and strength of the pressing member 7 can be easily increased, and the holding force of the plurality of electromagnetic steel plates 4a can be further increased.

As described above, according to the present embodiment, both weight reduction and high rigidity can be achieved by the plurality of pairs of pressing members 7. Therefore, the natural frequency of the rotating electric machine 1 can be increased, and the power supply frequency can also be increased. Can be detuned. As a result, the range of use of the rotary electric machine 1 is expanded, and the degree of freedom in design and expansion of specifications can be achieved. In addition, when the pressing member 7 is configured in an annular shape, the inner peripheral portion of the pressing member 7 is not used as a product, but the divided shape improves the yield in manufacturing the parts, thereby reducing the cost and improving the productivity. and make effective use of resources possible.

[First modification]
FIG. 3 is a cross-sectional view of a rotating electrical machine 1A of a first modified example, and FIG. 4 is a front view of the rotating electrical machine 1A. The rotary electric machine 1A has the same configuration as the rotary electric machine 1 of the above embodiment. Therefore, the rotary electric machine 1A can obtain the same actions and effects as those of the above embodiment based on the same configuration.

However, in this modified example, as shown in FIGS. 3 and 4, the second portion 7b is provided on the inner peripheral side of the first portion 7a, that is, on the radially inner end portion, unlike the above-described embodiment. are different. The second portion 7 b protrudes from the first portion 7 a in the axial direction opposite to the stator 3 , and is positioned radially outward adjacent to (adjacent to) the coil 5 . That is, the radially inner surface of the second portion 7 b faces the coil 5 .

The pressing member 7 is configured in a substantially L shape when viewed perpendicularly to the axial direction (see FIG. 3). In this modified example, the second portion 7b is configured in a straight line when viewed from the axial direction (see FIG. 4), but is not limited to this example. It may be configured in a circular arc shape along.

As described above, according to the present modification, the second portion 7b is provided at the end portion of the inner peripheral side of the first portion 7a, so that the second portion 7b can be arranged closer to the coil 5 as the heat source. can be done. This makes it easier for the heat of the coil 5 to escape to the second portion 7b by thermal radiation (radiation), and thus the cooling performance of the stator 3 can be further enhanced.

[Second modification]
FIG. 5 is a cross-sectional view of the rotating electric machine 1B of the second modification, and FIG. 6 is a front view of the rotating electric machine 1B. The rotary electric machine 1B has the same configuration as the rotary electric machine 1 of the above embodiment. Therefore, the rotary electric machine 1B can obtain the same actions and effects as those of the above embodiment based on the same configuration.

However, as shown in FIG. 5, this modified example differs from the above-described embodiment in that a heat radiating member 9 is provided between a pair of pressing members 7 . The heat dissipation member 9 has a plurality of fins 9a arranged in the axial direction and a base portion 9b connecting the plurality of fins 9a.

The base portion 9 b is formed in an arcuate plate shape extending along the outer peripheral surface 3 b of the stator 3 . The base portion 9b is thermally connected to the outer peripheral surface 3b of the stator 3 via a heat conducting member. The thermally conductive member is an adhesive, grease, or the like having thermal conductivity.

In this embodiment, by filling the gap between the base portion 9b and the outer peripheral surface 3b of the stator 3 with the heat conducting member, the thermal conductivity between the stator 3 and the heat radiating member 9 is improved through the heat conducting member. As a result, the cooling performance of the stator 3 can be further enhanced.

Each of the plurality of fins 9a protrudes radially outward from the base portion 9b and extends in an arc shape along the circumferential direction. In this embodiment, the height of the radially outer ends of the plurality of fins 9a and the height of the radially outer ends of the pressing member 7 are substantially the same.

Further, the plurality of fins 9a are fixed to a pair of pressing members 7 via couplings 8. As shown in FIG. In this embodiment, a nut 8b is fastened to a bolt 8a axially penetrating a portion of the pressing member 7 located radially outward of the outer peripheral surface 3b of the stator 3 and the plurality of fins 9a. , a plurality of electromagnetic steel plates 4 a are held between a pair of pressing members 7 .

In this modified example, the heat radiating member 9 and the pressing member 7 are thermally connected to each other through the coupler 8. , and the heat radiating member 9 and the pressing member 7 may be directly thermally connected.

As described above, according to this modification, since the heat radiating member 9 is provided using the space between the pair of pressing members 7, heat exchange between the plurality of fins 9a of the heat radiating member 9 and the air flow Heat dissipation is improved, and cooling of the stator 3 can be further enhanced.

In this modified example, the case where the pressing member 7 is not provided with the second portion 7b is exemplified. In addition, the second portion 7b may be provided at the end on the inner peripheral side of the first portion 7a.

According to such a configuration, the heat dissipation member 9 having the second portion 7b facing the coil 5 as a heat source and the plurality of fins 9a arranged in the axial direction further enhances the cooling performance (heat dissipation performance) of the stator 3. can be enhanced.

[Fourth Modification]
FIG. 8 is a cross-sectional view of a rotating electric machine 1D of a fourth modification, and FIG. 9 is a front view of the rotating electric machine 1D. A rotating electric machine 1D has a configuration similar to that of the rotating electric machine 1 of the above-described embodiment. Therefore, the rotary electric machine 1D can obtain the same actions and effects as those of the above-described embodiment based on the same configuration.

However, in this modified example, as shown in FIGS. 8 and 9, the pressing member 7 is provided with a plurality of second portions 7b, which is different from the above embodiment. Specifically, in this modified example, two second portions 7b are provided radially spaced apart from each other. The second portion 7b protrudes axially away from the stator 3 from the first portion 7a.

The pressing member 7 is configured in a substantially U shape with a first portion 7a and two second portions 7b as viewed perpendicularly to the axial direction (see FIG. 8). In addition, the number of the second portions 7b is not limited to two, and may be three or more. The second portion 7b is also referred to as a convex portion, a projecting portion, or the like.

As described above, according to the present modification, the surface area of the holding member 7 is increased by the plurality of second portions 7b. Coolability can be further enhanced. In addition, since the section modulus of the pressing member 7 is increased by the plurality of second portions 7b, the rigidity and strength of the pressing member 7 can be easily increased, and the holding force of the plurality of electromagnetic steel plates 4a can be further increased.

In this modified example, when viewed from the axial direction (see FIG. 9), the pressing member 7 protrudes radially outward from the outer peripheral surface 3b of the stator 3, but is not limited to this example. As in a rotating electric machine 1E of a fifth modified example shown in FIG. 10, the pressing member 7 may be provided so as to be aligned with the outer peripheral surface 3b of the stator 3 in the axial direction.

According to such a configuration, the casing of the rotating electrical machine 1E that houses the stator 3 and the pressing member 7, and thus the rotating electrical machine 1E, can be configured more compactly and lighter.

Although the embodiments and modifications of the present invention have been illustrated above, the above-described embodiments and modifications are examples and are not intended to limit the scope of the invention. The above embodiments and modifications can be implemented in various other forms, and various omissions, replacements, combinations, and modifications can be made without departing from the scope of the invention. In addition, specifications such as each configuration and shape (structure, type, direction, format, size, length, width, thickness, height, number, arrangement, position, material, etc.) may be changed as appropriate. can be implemented.

DESCRIPTION OF SYMBOLS 1, 1A-1E... Rotating electric machine, 2... Rotor, 2a... Outer peripheral surface, 3... Stator, 3a... End surface, 4a... Electromagnetic steel plate, 5... Coil, 7... Pressing member, 7a... First part, 7b... Second part , 8... Coupler, 9... Heat radiating member, 9a... Fin, Ax... Center of rotation, C... Circumferential direction, R... Radial direction, X... Axial direction.

Claims (4)

a rotor rotatable around the center of rotation;
a stator having a plurality of electromagnetic steel sheets laminated in the axial direction of the rotation center and arranged to face the outer peripheral surface of the rotor;
A plurality of magnetic steel plates are provided on both sides of the stator in the axial direction, hold the plurality of magnetic steel plates in a state of being sandwiched therebetween via couplings, and are spaced apart from each other in the circumferential direction of the rotation center. a pair of pressing members;
with
The pair of pressing members has a first portion facing the axial end face of the stator, and a second portion extending from the first portion in the axial direction opposite to the stator. . The stator has a coil,
The rotating electric machine according to claim 1, wherein the second portion is provided so as to face the coil from an inner peripheral side end portion of the first portion. 3. The electric rotating machine according to claim 1, further comprising a heat radiating member thermally connected to an outer peripheral surface of said stator and having a plurality of fins arranged in said axial direction, provided between said pair of pressing members. . 4. The electric rotating machine according to claim 1, wherein said pair of holding members are provided with a plurality of said second portions spaced apart from each other in a radial direction of said rotation center.

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