CN110971025B

CN110971025B - Motor

Info

Publication number: CN110971025B
Application number: CN201910923630.9A
Authority: CN
Inventors: 野田伸一; 佐久间裕一; 佐佐木雅贵
Original assignee: Nidec Corp
Current assignee: Nidec Corp
Priority date: 2018-09-28
Filing date: 2019-09-27
Publication date: 2022-04-08
Anticipated expiration: 2039-09-27
Also published as: JP2020058115A; CN110971025A

Abstract

The invention provides a motor. The motor of the invention can reduce vibration and noise. A motor (1) is provided with: a stator core (20) having at least one radially protruding projection (22) or radially recessed recess (23); and a motor leg portion (40) located on one side of the motor shaft (10) in the axial direction, the motor leg portion (40) having an outer shape that is line-symmetrical with respect to a symmetry axis passing through the shaft center when viewed in the axial direction, and the protruding portion (31) or the recessed portion (32) being located in a direction that has an angle with respect to the symmetry axis when viewed in the axial direction.

Description

Motor

Technical Field

The present invention relates to a motor.

Background

A stator core of a rotating electric machine including a plurality of divided cores is known. For example, patent document 1 describes a configuration in which a recessed portion is disposed on the peripheral outer circumferential surface of the joint portion of the divided cores adjacent to each other. According to patent document 1, by increasing the holding force between the split stator core and the outer cylinder core, a stator of a rotating electric machine having a high vibration/noise reduction effect can be obtained.

Documents of the prior art

Patent document

Patent document 1: japanese patent laid-open publication No. 2017-204912

Disclosure of Invention

Problems to be solved by the invention

However, the stator core formed of a plurality of divided cores has a lower roundness than a stator core of a punching integrated structure due to the influence of mounting accuracy, dimensional error, and the like when formed into a ring shape. Thus, in the stator core including the plurality of divided cores, the circumferential width of the air gap between the rotor and the stator is not uniform, and thus variation in electromagnetic force due to eccentricity occurs. The fluctuation of the electromagnetic force may increase vibration and noise.

In view of the above problems, it is an object of the present invention to provide a motor capable of reducing vibration and noise.

Means for solving the problems

A motor according to an exemplary aspect of the present invention includes: a stator core having at least one protruding portion protruding in a radial direction or an immersing portion immersing in the radial direction; and a motor leg portion located on one side of the motor shaft in the axial direction, the motor leg portion having an outer shape that is line-symmetric with respect to a symmetry axis passing through the shaft center when viewed in the axial direction, and the protruding portion or the recessed portion being located in a direction having an angle with respect to the symmetry axis when viewed in the axial direction.

Effects of the invention

According to the present invention, a motor capable of reducing vibration and noise can be provided.

Drawings

Fig. 1 is a perspective view showing an external appearance of a motor according to the present embodiment.

Fig. 2 is a plan view showing an external appearance of the motor according to the present embodiment.

Fig. 3 is an axial sectional view showing an internal structure of the motor according to the present embodiment.

Fig. 4 is a plan view when the stator core is formed of a straight bar core.

Fig. 5A is a schematic view of a convex stator core when a straight core is molded into an annular shape.

Fig. 5B is a schematic view of a stator core having a concave shape when a straight core is molded into an annular shape.

Fig. 6A is a plan view when the stator core is formed of two divided cores.

Fig. 6B is a plan view when the stator core is formed of three divided cores.

Fig. 7 is a schematic view of the case where the motor having the straight core is disposed in the rectangular motor leg portion in the present embodiment.

Fig. 8 is a schematic view of the case where the motor having two split cores is disposed in a rectangular motor leg portion in the present embodiment.

Fig. 9 is a schematic view of the case where the motor having three split cores is disposed in a rectangular motor leg portion in the present embodiment.

Fig. 10 is a plan view of the stator core having slots in the present embodiment.

Fig. 11 is a diagram comparing vibration displacements of a conventional motor and the motor according to the present embodiment.

Fig. 12 is a schematic diagram for explaining a vertical modification of the conventional motor.

Fig. 13 is a schematic diagram for explaining a torsional deformation of a conventional motor.

Fig. 14 is a schematic diagram for explaining vibration of the motor foot.

Fig. 15 is a schematic diagram showing a conventional example of a positional relationship between a stator core formed of straight cores and a motor leg.

Description of the symbols

1 … … Motor

10 … … Motor shaft

20 … … stator core

30 … … connecting part

31 … … projection

32 … … immersion part

40 … … Motor foot

50 … … reinforcing rib

60 … … bolt hole

70 … … groove

Detailed Description

Embodiments suitable for the present invention will be described with reference to the accompanying drawings. In the drawings, the same reference numerals denote the same or similar components. In the present embodiment, the axial direction refers to the axial direction of the motor shaft, and the radial direction refers to the radial direction of the stator core.

[ Structure of Motor ]

First, the structure of an embodiment of the motor according to the present invention will be described with reference to fig. 1 to 9. Fig. 1 is a perspective view showing an external appearance of a motor according to the present embodiment. Fig. 2 is a plan view showing an external appearance of the motor according to the present embodiment. Fig. 3 is an axial sectional view showing an internal structure of the motor according to the present embodiment.

As shown in fig. 1 to 3, the motor 1 according to the present embodiment includes a motor shaft 10, a stator core 20, motor legs 40, reinforcing ribs 50, and bolt holes 60. Hereinafter, each constituent element will be described.

As shown in fig. 3,

bearings

4 and 4 are incorporated in the center portion of the upper surface flange portion 3 and the center portion of the motor leg portion 40 of the cylindrical motor main body (housing) 2. The motor shaft 10 is rotatably supported in the

bearings

4 and 4. A rotor 6 is fixed around the motor shaft 10. A stator core 20 is provided around the rotor 6 with an air gap therebetween. The rotor 6 rotates within the stator core 20.

Fig. 4 is a plan view when the stator core is formed of a straight bar core. Fig. 5A is a schematic view of a convex stator core when a straight core is molded into an annular shape. Fig. 5B is a schematic view of a stator core having a concave shape when a straight core is molded into an annular shape.

The stator core 20 covers the periphery of the rotor 6 in the cylindrical motor main body (housing) 2 (see fig. 3). The stator core 20 is configured by molding a plurality of segment cores 21 into an annular shape. The stator core 20 of the present embodiment is configured by molding 12 divided cores 21 into an annular shape. In fig. 4, the stator core 20 is formed of a straight bar core. That is, the stator core 20 is a single member, and is a member in which the plurality of divided cores 21 are connected to each other except for one connecting portion 30. The plurality of divided cores 21 are molded into an annular shape, and the connection portions 30 are connected by welding or the like, thereby forming the annular stator core 20. The stator core 20 includes an arc-shaped yoke 22 and T-shaped teeth 23 protruding radially inward on the inner periphery of the yoke 22. A coil (not shown) is wound around the teeth 23.

As shown in fig. 5A, when the straight core is molded into an annular shape, the radially inner outer shape of the stator core 20 (the line connecting the radially inner circumferential surfaces of the teeth in an imaginary manner) has a convex shape (water droplet shape) with a portion protruding radially outward. In this case, a protrusion 31 protruding in the radial direction is formed at the stator core 20. On the other hand, as shown in fig. 5B, when the straight core is molded into an annular shape, the outer shape of the radially inner side of the stator core 20 (the line connecting the radially inner peripheral surfaces of the teeth in an imaginary manner) may be a concave shape (apple shape) in which a part is recessed radially inwardly. In this case, an immersion portion 31 that is immersed in the radial direction is formed in the stator core 20. The radially inner outer shape (a line connecting the inner circumferential surfaces of the teeth in the radial direction in an imaginary manner) shown in fig. 5A and 5B is an outline that emphasizes the shape of the protruding portion or the recessed portion for the sake of explanation, and is different from an actual scale.

Thus, at least one protruding portion 31 protruding in the radial direction or an indented portion 32 indented in the radial direction is formed in the stator core 20. That is, the stator core 20 has at least one protruding portion or recessed portion. The protruding portion 31 or the recessed portion 32 is a connecting portion 30 that connects the divided cores 21. The number of the protruding portions 31 or the recessed portions 32 differs depending on the stator core 20 being composed of several parts. As shown in fig. 4, in the case where the stator core 20 is formed of a straight bar core, the connection portion 30 exists at one place.

Fig. 6A is a plan view when the stator core is formed of two divided cores. Fig. 6B is a plan view when the stator core is formed of three divided cores.

In fig. 6A, the stator core 20 is formed of two divided cores. That is, the stator core 20 is two members, and is a member in which the plurality of divided cores 21 are connected to each other except for two connecting portions 30. The two divided cores are molded into an annular shape, and the two connection portions 30 are connected by welding or the like, thereby forming the annular stator core 20. In the case where the stator core 20 is formed of two divided cores, the connection portions 30 exist at two places. In the case of two divided cores, the connecting portions 30 are arranged at an angle of 180 degrees from each other in the circumferential direction and face each other in the radial direction.

In fig. 6B, the stator core 20 is formed of three divided cores. That is, the stator core 20 is three members, and is a member in which the plurality of divided cores 21 are connected to each other except for three connecting portions 30. The two divided cores are molded into an annular shape, and the three connection portions 30 are connected by welding or the like, thereby forming the annular stator core 20. In the case where the stator core 20 is formed of three divided cores, the connection portions 30 exist at three places. In the case of three divided cores, the connecting portions 30 are arranged at an angle of 120 degrees from each other in the circumferential direction.

Referring to fig. 1 and 2, the motor leg 40 is located on one axial side of the motor shaft 10. In the present embodiment, the motor leg portion 40 is located at the bottom portion of the motor shaft 10 on the side opposite to the upper surface flange portion 80. The motor leg 40 and the motor main body (housing) 2 are formed as an integral structure. The outer shape of the motor leg portion 40 is a line-symmetric shape with respect to a symmetry axis passing through the shaft center when viewed from the axial direction. The shaft center is the center of the motor shaft.

Examples of the line-symmetric shape of the motor leg 40 include a polygonal shape, a rectangular shape, a triangular shape, an elliptical shape, and an oblong shape when viewed from the axial direction. The polygonal shape is a concept including a substantially polygonal shape obtained by chamfering corners. The rectangular shape is a concept including a substantially rectangular shape obtained by chamfering a corner portion. The triangular shape is a concept including a substantially triangular shape obtained by chamfering corners. In the case where the motor leg 40 has the illustrated shape, the protruding portion 31 or the recessed portion 32 is located in a direction having an angle with respect to the axis of symmetry when viewed from the axial direction. In the present embodiment, the protruding portion 31 or the recessed portion 32 is not parallel to the axis of symmetry. In the present embodiment, the protruding portion 31 or the recessed portion 32 is not perpendicular to the axis of symmetry.

Fig. 7 is a schematic view of the case where the motor having the straight core is disposed in the rectangular motor leg portion in the present embodiment. Fig. 8 is a schematic view of the case where the motor having two split cores is disposed in a rectangular motor leg portion in the present embodiment. Fig. 9 is a schematic view of the case where the motor having three split cores is disposed in a rectangular motor leg portion in the present embodiment.

As shown in fig. 7 to 9, when the outer shape of the motor leg 40 is rectangular, the protruding portion 31 is located in a diagonal direction of the outer shape of the motor leg 40 with respect to the shaft center when viewed from the axial direction. In fig. 7, the motor 1 in which the stator core is formed of a straight core is disposed in the rectangular motor leg 40, and one of the projections 31 is located in the direction of the rectangular diagonal line 41. In fig. 8, the motor 1 in which the stator core is formed by two divided cores is arranged in the rectangular motor leg 40, and two protrusions 31 facing each other in the radial direction are located in the direction of the rectangular diagonal line 41. In fig. 9, the motor 1 in which the stator core is formed by three divided cores is arranged in a rectangular motor leg 40, and three protrusions 31 that are separated by an angle of 120 degrees in the circumferential direction are located in a direction close to the direction of a rectangular diagonal line 41. In the case of three divided cores, all of the three protruding portions or the three recessed portions do not face the short-side direction or the longitudinal direction of the motor leg portion 40 when viewed from the axial direction. That is, all three of the projections or dips are in an angled orientation relative to the axis of symmetry of the motor foot 40 through the shaft center.

Referring to fig. 1 and 2, the motor leg 40 has a reinforcing rib 50. The reinforcing ribs 50 reinforce the motor leg 40. The reinforcing ribs 50 are plate-shaped. The reinforcing ribs 50 prevent the motor foot 40 from being deformed by vibration. The reinforcing ribs 50 connect the motor leg 40 and the motor main body (housing) 2. Referring to fig. 7 to 9, the reinforcing rib 50 is arranged in the direction of the protruding portion 31 (or the recessed portion 32) with respect to the motor main body 2 when viewed from the axial direction. That is, the reinforcing ribs 50 are arranged in the direction of the diagonal line 41 of the motor leg 40. As shown in fig. 1, the plate thickness T of the reinforcing rib 50 has a thickness equal to the axial thickness T of the motor leg 40. The axial height H of the reinforcing rib 50 is equal to the axial height H of the stator core 20.

As shown in fig. 7 to 9, the bolt hole 60 is a hole for inserting a bolt (not shown) to fix the motor 1 to the apparatus main body and mount the motor to the apparatus. The motor foot 40 has a plurality of bolt holes 60. Preferably, the reinforcing rib 50 is located radially inward of the bolt hole 60. That is, in the motor leg 40, the bolt hole 60 is located radially inward of the radially outer distal end portion of the reinforcing rib 50.

Fig. 10 is a plan view of the stator core having slots in the present embodiment. As shown in fig. 10, a radially recessed groove 70 is provided in a part of the outer circumferential surface of the stator core 20. The slots 70 are slot portions for positioning the stator core 20. Positioning of stator core 20 in the circumferential direction can be easily performed by inserting a tool into groove 70 or the like. In the present embodiment, the groove 70 is formed at one position on the outer peripheral surface of the stator core 20, but two or more positions may be formed. It is preferable that the groove 70 is formed at a position opposite to a position where the connection portion 30 (the protruding portion or the recessed portion) is located in the radial direction. This is because the position of the connecting portion 30 (protruding portion or recessed portion) can be easily confirmed at the time of assembly.

Preferably, the number of poles of the motor 1 according to the present embodiment is 10, and the number of grooves is 12. This is because, in the motor 1 having 10 poles and 12 slots, the electromagnetic force pattern is elliptical, and vibration and noise due to electromagnetic force fluctuation due to eccentricity are likely to occur, and therefore, it is desirable to apply the present invention.

[ Effect of Motor ]

Next, the operation of the motor 1 according to the present embodiment will be described with reference to fig. 7 to 9 and 11. In the following description, a motor having a rectangular motor leg portion is exemplified.

Fig. 12 is a schematic diagram for explaining a vertical modification of the conventional motor. As shown in fig. 12, in a conventional motor having rectangular motor legs and a cylindrical motor body (housing), electromagnetic force acts, and the cylindrical housing is deformed into an elliptical shape. Since the motor main body (housing) and the motor leg portion are integrally structured, if the cylindrical housing is deformed into an elliptical shape in the X-X direction and the Y-Y direction, the motor leg portion is deformed in the Z-Z direction.

As a specific example, for example, in a motor having 10 poles and 12 slots, the above-described elliptical deformation is easily generated by an electromagnetic force. The vibration and noise generated by the above-described elliptical deformation are likely to be a problem in the operating region (rotational speed) of the practical washing machine. In order to reduce vibration and noise, the motor leg needs to be configured so as not to be easily displaced in the Z-Z direction.

Fig. 13 is a schematic diagram for explaining a torsional deformation of a conventional motor. Assuming that the Y-Y axis is a 0 degree rotational position, the rotational position of the rotor increases in the counterclockwise direction of rotation. The vibration is generated with respect to the direction from the center of the shaft to the position of the rotor. As shown in fig. 13, the deformation of the motor leg portion becomes a torsional deformation at the 45-degree rotation position. In the torsional deformation, the displacement in the Z-Z direction is small, and the amount of vibration displacement converted into sound in the motor mounting plate is reduced, thereby reducing noise. That is, the motor leg is hardly damaged by vibration in the direction of the 45-degree rotation position, and vibration and noise are hardly generated.

Fig. 14 is a schematic diagram for explaining vibration of the motor foot. In fig. 14, a motor 101 is attached to a motor attachment plate 104. Motor 101 drives gear 103 via drive belt 102. The motor mounting plate 104 is mounted on a device to be mounted, such as a washing machine. The vibration of the motor is propagated from the motor foot to the motor mounting plate 104. The entire motor mounting plate 104 vibrates as one, two, or three times by the propagation of the vibration, and the radiation area increases, thereby causing the noise to spread.

Fig. 15 is a schematic diagram showing a conventional example of a positional relationship between a stator core formed of straight cores and a motor leg. The stator core of the conventional example shown in fig. 15 is formed of a straight core, and the protruding portion is present at one position. The motor leg is rectangular when viewed in the axial direction. In the conventional example shown on the left side, the protruding portion is located in a direction perpendicular to the long side of the motor leg portion when viewed from the axial direction. In the conventional example shown on the right side, the protruding portion is located in a direction perpendicular to the short side of the motor leg portion when viewed from the axial direction. The local electromagnetic force of the projection is likely to be lower than that of other portions, and the radial exciting force at that position is increased. Therefore, in the conventional example, the vibration direction of the vibration mode of the motor leg portion coincides with the direction of the excitation force, and the vibration tends to increase. In the present embodiment, since the protruding direction of the protruding portion does not coincide with the direction of the vibration mode of the motor leg portion, vibration can be suppressed.

In order to avoid the deformation of the motor from increasing relative to the exciting force, a resin molding part is arranged around the stator core to enhance the rigidity. However, it is not preferable to increase the thickness of the resin mold portion to increase the overall weight greatly.

Therefore, as shown in fig. 7 to 9, in the motor 1 according to the present embodiment, the reinforcing ribs 50 are formed only at four positions in the direction of the longest diagonal line 41 in the rectangular motor leg portion 40. By providing the reinforcing ribs 50 in the direction of the diagonal line 41, it is possible to minimize an increase in weight and to suppress deformation of the stator core 20 to the maximum extent to reduce vibration.

Further, the connection portion (protruding portion 31 or recessed portion 32) of the divided core 21 is arranged toward the position of the reinforcing rib 50. Even if an exciting force is generated due to a variation in electromagnetic force generated in the direction of the protruding portion 31 or the recessed portion 32 of the divided core 21, the reinforcing rib 50 can be suppressed from being deformed.

In a motor of a type in which electromagnetic forces of relative positions are generated simultaneously, such as a motor having 10 poles and 12 slots, vibration is likely to be a problem. In the motor 1 according to the present embodiment, since the "exciting force in the direction of the connection portion of the divided cores" depends on the reinforcing structure of the reinforcing rib 50, the vibration does not increase.

Fig. 11 is a diagram comparing vibration displacements of a conventional motor and the motor according to the present embodiment. As shown in fig. 11, the motor 1 according to the present embodiment has significantly reduced vibration compared to the conventional motor. That is, according to the motor 1 of the present embodiment, the vibration transmitted to the motor leg portion from the top to the bottom is reduced. Even when the circularity of the stator core is impaired by using the split cores, vibration can be reduced, and the motor capable of reducing vibration transmitted to a device to be mounted can be provided.

As described above, the motor 1 according to the present embodiment includes: a stator core 20 having at least one protrusion 31 protruding in a radial direction or an immersion 32 sinking in the radial direction; and a motor leg 40 located on one axial side of the motor shaft 10. The outer shape of the motor leg portion 40 is line-symmetrical with respect to a symmetry axis passing through the shaft center when viewed from the axial direction, and the protruding portion 31 or the recessed portion 32 is located in a direction having an angle with respect to the symmetry axis when viewed from the axial direction. According to this aspect, since the protruding portion 31 or the recessed portion 32 is located in the direction intersecting the extension line of the side of the outer shape of the motor leg 40 when viewed from the axial direction, the direction of the vibration of the motor leg 40 is shifted from the direction of the excitation force generated by the discontinuous portion of the stator core 20, and therefore the vibration and noise of the motor 1 can be reduced.

The protruding portion 31 or the recessed portion 32 of the motor 1 according to the present embodiment is a connecting portion 30 that connects the divided cores 21. According to this aspect, vibration and noise of the motor 1 due to a dimensional error in the connection portion 30 can be reduced.

The stator core 20 of the motor 1 according to the present embodiment is formed of a straight core, and the connection portion 30 is present at one location. According to this mode, the vibration and noise of the motor 1 formed of the straight iron core are effectively reduced.

The stator core 20 of the motor 1 according to the present embodiment may be formed of two split cores, and the connection portions 30 may be present at two locations, the two connection portions 30 facing each other in the radial direction. According to this mode, the vibration and noise of the motor 1 formed of the two divided cores are effectively reduced.

The stator core of the motor 1 according to the present embodiment may be formed of three divided cores, and the three connection portions 30 may be present at three positions, and the three connection portions 30 may be arranged at angles of 120 degrees in the circumferential direction. According to this mode, the vibration and noise of the motor 1 formed of the three divided cores are effectively reduced.

The motor leg 40 of the motor 1 according to the present embodiment has a polygonal shape when viewed from the axial direction. According to this embodiment, in the motor with the transmission belt, the polygonal motor leg portion 40 easily receives the tension of the transmission belt, and the vibration and noise of the motor 1 having the polygonal motor leg portion 40 are effectively reduced.

Further, the protruding portion 31 or the recessed portion 32 of the motor 1 according to the present embodiment is preferably located in the diagonal direction of the outer shape of the motor leg portion 40 with respect to the axial center when viewed from the axial direction. According to this embodiment, since the projection 31 or the recessed portion 32 is positioned in the diagonal direction of the outer shape of the motor leg 40, which is less likely to generate vibration, vibration and noise of the motor due to the exciting force of the projection 31 or the recessed portion 32 can be reduced.

The motor leg 40 of the motor 1 according to the present embodiment may have a rectangular shape when viewed from the axial direction. According to this aspect, the space in the motor leg other than the region supporting the motor main body (housing) can be made small. Therefore, the motor can be easily attached to the motor attachment plate, and the cost can be reduced. In the motor with the belt, if the rectangular corners are arranged in the direction in which the tension of the belt is applied, the rectangular motor leg portions 40 easily receive the tension of the belt, and the vibration and noise of the motor 1 having the rectangular motor leg portions 40 are effectively reduced.

The motor leg 40 of the motor 1 according to the present embodiment may have a triangular shape when viewed from the axial direction. According to this aspect, in the motor with the belt, if the rectangular corner portion is disposed in the direction in which the tension of the belt is applied, the triangular motor leg portion easily receives the tension of the belt, and the vibration and noise of the motor having the triangular motor leg portion 40 are effectively reduced. The triangular motor leg is less likely to create a wasted space when arranged as described above, compared to other shapes.

Further, the motor leg portion 40 of the motor 1 according to the present embodiment may be elliptical or oblong when viewed from the axial direction. According to this aspect, the space in the motor leg other than the region supporting the motor main body (housing) can be made small. Therefore, the motor can be easily attached to the motor attachment plate, and the cost can be reduced.

Further, the motor leg 40 of the motor 1 according to the present embodiment preferably has a reinforcing rib 50 connected to the motor main body 2. According to this embodiment, since the motor leg 40 has the reinforcing ribs 50, deformation of the stator core 20 is suppressed, and vibration and noise of the motor 1 can be reduced.

Further, the reinforcing ribs 50 of the motor 1 according to the present embodiment are preferably arranged in the direction of the protruding portion 31 or the recessed portion 32 from the motor main body 2. According to this embodiment, since the motor leg 40 has the reinforcing ribs 50, deformation of the stator core 20 is suppressed, and vibration and noise of the motor 1 can be reduced.

Further, the reinforcing rib 50 of the motor 1 according to the present embodiment is preferably plate-shaped, and the plate thickness T of the reinforcing rib 50 is equal to the axial thickness T of the motor leg 40. According to this embodiment, by making the plate thickness T of the reinforcing rib 50 equal to the axial thickness T of the motor leg 40, it is possible to reduce vibration and noise of the motor 1 while suppressing an increase in weight due to the formation of the reinforcing rib 50.

Further, it is preferable that the motor leg portion 40 of the motor 1 according to the present embodiment has the bolt hole 60, and the reinforcing rib 50 is located radially inward of the bolt hole 60. According to this aspect, since the reinforcing rib 50 is located radially inward of the bolt hole 60, it is possible to reduce vibration and noise of the motor 1 while suppressing an increase in weight due to the formation of the reinforcing rib 50.

In the motor 1 according to the present embodiment, the axial height H of the reinforcing rib 50 is preferably equal to the axial height H of the stator core 20. According to this embodiment, by making the axial height H of the reinforcing rib 50 equal to the axial height H of the stator core 20, it is possible to reduce vibration and noise of the motor 1 while suppressing an increase in weight due to the formation of the reinforcing rib 50.

Further, in the motor 1 according to the present embodiment, it is preferable that the outer peripheral surface of the stator core 20 is provided with a groove 70. According to this embodiment, by providing the slots 70 on the outer peripheral surface of the stator core 20, positioning of the stator core 20 in the circumferential direction is facilitated when the stator core 20 is mounted.

Further, the number of poles of the motor 1 according to the present embodiment is preferably 10, and the number of grooves is preferably 12. In the motor 1 having the divided cores with 10 poles and 12 slots, the electromagnetic force pattern is elliptical, and noise is a problem. According to this aspect, the motor 1 can exhibit a noise reduction effect.

The above-described embodiments are for facilitating understanding of the present invention, and should not be construed as limiting the present invention. The elements, the arrangement, the materials, the conditions, the shapes, the specifications, and the like of the embodiments are not limited to the examples, and can be appropriately modified. Further, the configurations shown in the different embodiments can be partially replaced or combined with each other.

In the above-described embodiment, the motor having the motor leg portion having the rectangular shape is exemplified, but the motor having the motor leg portion having the polygonal shape, the triangular shape, the elliptical shape, and the oblong shape has the same operational effect. In the above-described embodiment, the motor having the stator core formed of the straight core or the two split cores or the three split cores is exemplified, but the stator core formed of four split cores or a larger number of components may be used. The present invention can also be applied to a motor in which the motor body (housing) and the motor leg have the same shape when viewed in the axial direction.

[ industrial applicability ]

The motor according to the present embodiment can be applied not only to a washing machine but also to a flange motor used in a machine tool, a pump, or the like, as long as the motor has a cylindrical motor body (housing) and a motor leg.

Claims

1. A motor, comprising:

a stator core having at least one protruding portion protruding in a radial direction or an immersing portion immersing in the radial direction; and

a motor leg portion located at one side of the motor shaft in an axial direction,

the outer shape of the motor leg portion is a shape that is line-symmetrical with respect to a symmetry axis passing through a shaft center when viewed from the axial direction, and the protruding portion or the recessed portion is located in a direction having an angle with respect to the symmetry axis when viewed from the axial direction.

2. The motor of claim 1,

the protruding portion or the recessed portion is a connecting portion connecting the divided cores.

3. The motor of claim 2,

the stator core is formed of straight bar cores, and the connecting portion exists at one place.

4. The motor of claim 2,

the stator core is formed of two divided cores, and the connecting portions exist at two places, the connecting portions being opposed to each other in the radial direction.

5. The motor of claim 2,

the stator core is formed of three divided cores, the connecting portions are present at three positions, and the three connecting portions are arranged at angles of 120 degrees in the circumferential direction.

6. The motor according to any one of claims 1 to 5,

the motor leg is polygonal in shape when viewed from the axial direction.

7. The motor of claim 6,

the protruding portion or the recessed portion is located in a diagonal direction of an outer shape of the motor leg portion with respect to an axial center when viewed from an axial direction.

8. The motor of claim 6,

the motor leg is rectangular when viewed in the axial direction.

9. The motor of claim 6,

the motor foot is triangular in shape when viewed axially.

10. The motor of claim 1,

the motor leg has a reinforcing rib connected to the motor main body.

11. The motor of claim 10,

the reinforcing rib is disposed in a direction in which the protruding portion or the recessed portion is located with respect to the motor main body when viewed from the axial direction.

12. The motor of claim 10,

the reinforcing ribs are plate-shaped, and the plate thickness of the reinforcing ribs is equal to the axial thickness of the motor leg.

13. The motor of claim 10,

the motor leg has a bolt hole, and the reinforcing rib is located radially inward of the bolt hole.

14. The motor of claim 10,

the axial height of the reinforcing rib is equal to the axial height of the stator core.

15. The motor of claim 1,

the motor foot is oval or oblong when viewed axially.

16. The motor of claim 1,

a slot is provided on the outer peripheral surface of the stator core.

17. The motor of claim 1,

the number of poles of the motor is 10 poles, and the number of grooves is 12 grooves.