JP2023127600A - Rotor and motor - Google Patents

Abstract

To provide a rotor or a motor having a structure capable of stably attaching a bearing without being affected by abrasion powder generated during press-in of the rolling bearing.SOLUTION: A rotor is provided with a protrusion 18 protruding in a cylindrical axis direction from a press-in jig facing surface 27 of a cylindrical inner ring 13. The protrusion 18 is configured to be provided all over the circumference of a disk face on an outer peripheral end than an inner peripheral end of the inner ring 13 and comprise a flat plane vertical to the cylindrical axis direction at a front end. By this configuration, it is enabled to always apply pressure to only the inner ring 13 via application of a uniform load, when pressing a rolling bearing 5 in a shaft 9. Further, even when cutting powder of the shaft 9, and abrasion powder via friction between the rolling bearing 5 and the shaft during press-in are generated, these foreign matters are stored in a storage space 20, thereby being able to obtain effects of preventing the abrasion powder from entering the rolling bearing 5, and preventing the abrasion powder from being attached to a press-in jig 19.SELECTED DRAWING: Figure 5

Description

The present invention relates to a rotor and a motor.

Conventionally, when inserting a rolling bearing into a shaft or a housing, a method of pressing using a press-fitting jig or the like has been known. The press-fitting surface of the press-fitting jig faces the press-fitted surface of the rolling bearing, and can press the press-fitted surface while applying an even load perpendicularly to the press-fitted surface. If a load misalignment occurs, the rolling bearing will be inserted at an angle, causing damage such as flaking and deterioration of the roundness of the rolling elements, and causing abnormal noise in the rolling bearing.

Therefore, methods for stably press-fitting rolling bearings in a plane perpendicular to the press-fitting direction have been studied, and one known example is a bearing mounting structure that is provided with a positioning part that allows loose insertion of rolling bearings (for example, , see Patent Document 1). The structure will be explained below with reference to FIG.

FIG. 9 is a cross-sectional view of the rolling bearing mounting structure in Patent Document 1. A positioning portion 114 is formed in the bearing housing 112 provided on the frame 103 by making the outer diameter of the bearing housing 112 slightly larger than the outer diameter of the rolling bearing 102 near the open end 113 thereof. Further, below the positioning portion 114 provided near the open end 113 of the inner circumferential surface of the bearing housing 112, the diameter of the inner circumferential surface of the bearing housing 112 is set such that the rolling bearing 102 can be press-fitted and fixed. It is formed slightly smaller than the outer diameter.

With the above configuration, when the rolling bearing 102 is loosely inserted into the open end 113 of the bearing housing 112, the rolling bearing 102 is held by the positioning portion 114 and can be correctly positioned in the press-fitting direction of the bearing housing 112.

Utility Model Publication No. 62-166324

Such a conventional configuration has the following problems.

In the conventional configuration, when the rolling bearing is press-fitted into the housing, wear particles are generated due to friction between the rolling bearing and the housing. Since there is no gap between the rolling bearing and the housing, there is a risk that foreign matter such as generated wear particles may enter the rolling bearing. Furthermore, if the press-fitting surface of the press-fitting jig becomes deformed due to abrasion powder adhering to the press-fitting jig used for press-fitting the rolling bearing, it becomes impossible to apply a uniform force to the rolling bearing during press-fitting. . As a result, there is a problem in that the rolling bearing cannot be press-fitted perpendicularly to the press-fitting surface, and abnormal noise is generated due to damage to the rolling bearing.

Additionally, even when a rolling bearing is press-fitted into a shaft, there is a similar problem in that the rolling bearing cannot be press-fitted perpendicularly to the press-fitting surface due to the effects of cutting debris from the shaft and wear debris between the rolling bearing and the shaft. .

Therefore, an object of the present invention is to provide a rotor having a structure in which a rolling bearing can be stably mounted without being affected by wear particles generated when the rolling bearing is press-fitted, and a motor equipped with the rotor. .

In order to solve the above problems, a rotor according to the present invention includes a rotor core, a shaft, and a rolling bearing inserted into the shaft, the rolling bearing being inserted into the shaft. The inner ring includes a cylindrical inner ring, an outer ring disposed on the outer periphery of the inner ring, and a plurality of rolling elements held rotatably between the outer periphery of the inner ring and the inner periphery of the outer ring. , a protrusion projecting in the axial direction of the cylindrical shape from at least one of the ends of the cylindrical shape, and between the protrusion and the shaft, when the inner ring is inserted into the shaft, A storage space is provided to store the generated wear debris, thereby achieving the intended purpose.

According to the present invention, it is possible to provide a rotor capable of suppressing the adverse effects of abrasion powder generated by press-fitting a rolling bearing, or a motor equipped with this rotor.

A sectional view of a motor according to Embodiment 1 of the present invention Cross-sectional view of the rolling bearing according to Embodiment 1 of the present invention when press-fitted A top view of the rolling bearing according to Embodiment 1 of the present invention, viewed from the press-fitting jig side A top view of the rolling bearing according to Embodiment 1 of the present invention, viewed from the press-fitting jig side Enlarged view of the rolling bearing press-fitted part in FIG. 2 according to Embodiment 1 of the present invention Cross-sectional view of a rolling bearing according to Embodiment 2 of the present invention when press-fitted A top view of a rolling bearing according to Embodiment 2 of the present invention, viewed from the press-fitting jig side A top view of a rolling bearing according to Embodiment 2 of the present invention, viewed from the press-fitting jig side Cross-sectional view of a rolling bearing mounting structure in a conventional configuration

Embodiments of the present invention will be described below with reference to the drawings. Note that the following embodiments are examples of embodying the present invention, and do not limit the technical scope of the present invention. In addition, throughout all the drawings, the same parts are given the same reference numerals and their explanations are omitted from the second time onwards. Further, in each drawing, detailed explanations of parts not directly related to the present invention are omitted or simplified.

(Embodiment 1)
A rotor and a motor according to Embodiment 1 of the present invention will be described with reference to FIG. 1. FIG. 1 is a sectional view schematically showing the internal configuration of a motor 1 equipped with a rotor according to the present invention.

The motor 1 is an inner rotor type DC motor, and for example, blades are attached to the shaft and air is blown by rotating the shaft. In the following explanation, the side of the top surface 23 of the mold body (the upper side in FIG. 1), which will be described later, will be referred to as the top surface direction, and the side facing the top surface 23 of the mold body (opening side of the mold body 2: the lower side in FIG. 1) will be referred to as necessary. ) is called the bottom direction.

The motor 1 includes a molded body 2, a bracket 6, and a rotor 7.

The mold body 2 has a hollow cylindrical shape with a circular mold body top surface 23 at one end and an open end, that is, a concave shape when viewed in cross section, and the rotor 7 is housed in the internal space of the concave shape. The mold body 2 is formed by processing resin, for example. The molded body 2 includes a stator 3, a winding 4, and a housing 21a.

Stator 3 is arranged around the outer periphery of rotor 7.

The winding 4 is a conductive wire mainly made of copper or aluminum alloy, and is wound around the stator 3. The winding 4 generates a magnetic field for rotating the rotor 7 by power supply.

The housing 21a has a hollow cylindrical shape protruding from the center of the mold body top surface 23 toward the top surface, and has a concave shape with an open end surface toward the bottom surface. The housing 21a houses a rolling bearing 5, which will be described later, in the concave internal space. The housing 21a is formed integrally with the mold body top surface 23. The housing 21a includes an insertion hole 24.

The insertion hole 24 is a through hole provided in the end surface of the housing 21a in the direction of the top surface. The shaft 9, which will be described later, is inserted into the insertion hole 24 from the inside of the molded body 2 to the outside. The insertion hole 24 is provided in a circular shape at the center of the end face in the direction of the top surface of the housing 21a.

The bracket 6 is arranged to cover the opening in the bottom direction of the mold body 2. In other words, the bracket 6 constitutes the outer shell of the motor 1 together with the molded body 2. The bracket 6 includes a housing 21b.

The housing 21b has a hollow cylindrical shape and has the same size as the housing 21a, and is provided so as to protrude from the center of the bracket 6 toward the bottom surface. The housing 21b has a concave shape with an open end face toward the top, and stores the rolling bearing 5 in the internal space of the concave shape.

The rotor 7 is rotatably fixed inside the motor 1 by a rolling bearing 5, which will be described later. The rotor 7 includes a shaft 9, a rotor core 11, and a permanent magnet 8. When the motor 1 is driven, the shaft 9 serves as a rotation axis and the rotor 7 rotates.

The shaft 9 has a cylindrical rod shape. Here, "cylindrical shape" means a round tube or columnar shape with a circular bottom surface. The shaft 9 virtually includes a rotation axis 22 passing through the center of both end surfaces of the cylindrical shape. The shaft 9 rotates around a rotating shaft 22 as a central axis. The shaft 9 includes a rolling bearing 5 and an E-ring 10.

The rolling bearing 5 rotatably fixes the shaft 9 inside the motor 1. The rolling bearing 5 has a hollow cylindrical shape and has an inner diameter equivalent to the outer diameter of the shaft 9 and an outer diameter equivalent to the inner diameters of a housing 21a and a housing 21b, which will be described later. One rolling bearing 5 is press-fitted from each end of the shaft 9. Details of the rolling bearing 5 will be described later.

The E-ring 10 is a locking portion that positions the rolling bearing 5 on the shaft 9. The E-ring 10 is, for example, in the shape of a hollow disk having an inner diameter equivalent to the outer diameter of the shaft 9. One E-ring 10 is provided at a position corresponding to the opening in the mold body 2 and at a position corresponding to the top surface 23 of the mold body.

The rotor core 11 has a cylindrical shape and has an inner diameter equivalent to the outer diameter of the shaft 9, and is inserted into the shaft 9. The rotor core 11 has a cylindrical shape by laminating a plurality of electromagnetic steel plates in the longitudinal direction of the shaft 9.

The permanent magnets 8 are, for example, sintered ferrite magnets, and are arranged at equal intervals around the outer circumference of the rotor core 11. Permanent magnet 8 is integrally formed with rotor core 11 by connecting member 12.

The connecting member 12 is made of, for example, a resin, and the permanent magnet 8 and the rotor core 11 are integrated by pouring melted resin between the permanent magnet 8 and the rotor core 11 and solidifying the resin.

Next, the structure of the rolling bearing 5 will be explained with reference to FIGS. 1 and 2. FIG. 2 is a cross-sectional view showing the movement when the rolling bearing 5 is press-fitted into the shaft 9.

A press-fit jig 19 is used to insert the rolling bearing 5 into the shaft 9 in this embodiment. The inner diameter of the rolling bearing 5 is equal to the outer diameter of the shaft 9, and as shown in FIG. Press in until you reach ring 10. As a result, the rolling bearing 5 is fitted onto the shaft 9. Here, the press-fitting direction in FIG. 2 is the bottom direction for the rolling bearing 5a in FIG. 1, and the top direction for the rolling bearing 5b in FIG.

The rolling bearing 5 of this embodiment includes an inner ring 13 and an outer ring 14.

The inner ring 13 has a cylindrical shape and has an inner diameter equivalent to the outer diameter of the shaft 9, and is inserted into the shaft 9. Inner ring 13 has an outer diameter smaller than the outer diameter of E-ring 10. Inner ring 13 is a rotating ring and rotates together with shaft 9. The inner ring 13 includes a press-fit jig facing surface 27, an E-ring facing surface 28, and a protrusion 18.

The press-fit jig facing surface 27 is a disk surface that faces the press-fit surface of the press-fit jig 19.

The E-ring opposing surface 28 is a disc surface that faces the E-ring 10.

The protrusion 18 is provided in the inner ring 13 so as to protrude from the press-fitting jig facing surface 27 in the opposite direction to the press-fitting direction. In other words, the protrusion 18 protrudes in the axial direction of the cylindrical inner ring 13. The protrusion 18 directly transmits the load from the press-fit jig 19 only to the inner ring 13 without directly transmitting it to the outer ring 14. The protruding portion 18 is provided on the outer circumferential side of the disk surface of the press-fitting jig facing surface 27 with respect to the inner circumferential end (the pressure contact portion with the shaft 9). In other words, the protrusion 18 is provided spaced apart from the shaft 9 in the outer circumferential direction. The protrusion 18 is, for example, integrally molded with the inner ring 13. The protrusion 18 includes a press-fitting surface 29. Furthermore, the protrusion 18 includes a storage space 20 between it and the shaft 9. Details of the press-fit surface 29 will be described later.

The storage space 20 is a space for storing wear powder generated when the rolling bearing 5 is press-fitted. The storage space 20 has a concave shape in cross-section surrounded by the protrusion 18, the press-fitting jig facing surface 27, and the shaft 9, and the opening in the concave shape faces the press-fitting surface of the press-fitting jig 19. provided.

The outer ring 14 has a cylindrical shape having an inner diameter larger than the outer diameter of the E-ring 10 and an outer diameter equivalent to the outer diameter of the housing 21, and is arranged on the outer periphery of the inner ring 13. The outer ring 14 is a fixed ring and does not rotate together with the shaft 9.

Note that U-shaped grooves 26 are provided on the outer periphery of the inner ring 13 and the inner periphery of the outer ring 14, respectively, in order to hold rolling elements 15, which will be described later.

Moreover, rolling elements 15, a retainer 16, and a shield 17 are provided between the outer circumference of the inner ring 13 and the inner circumference of the outer ring 14. Grease is filled between the outer circumference of the inner ring 13 and the inner circumference of the outer ring 14 to reduce wear on the rolling elements 15. As the grease, for example, a known grease for rolling bearings can be used.

The U-shaped groove 26 is provided over the entire outer circumference of the inner ring 13 and the inner circumference of the outer ring 14.

The rolling elements 15 are, for example, made of metal and formed into a spherical shape. A plurality of rolling elements 15 are held rotatably between two U-shaped grooves 26 provided on the outer periphery of the inner ring 13 and the inner periphery of the outer ring 14.

The retainer 16 is a member provided to keep the circumferential spacing between the plurality of rolling elements 15 constant. The retainer 16 holds the rolling element 15 from the press-fit jig facing surface 27 side and the E-ring facing surface 28 side.

The shield 17 has a hollow disk shape. The shield 17 is provided at both ends of the rolling bearing 5, with its inner circumferential side matching the outer circumference of the inner ring 13 and its outer circumferential side matching the inner circumference of the outer ring 14. In other words, the shield 17 is arranged to cover the openings at both ends of the rolling bearing 5 formed by the inner ring 13 and the outer ring 14.

Next, the structure of the protrusion 18 will be explained in detail with reference to FIGS. 3 and 4. 3 and 4 are top views of the rolling bearing 5 viewed from the press-fitting jig 19 side.

For example, as shown in FIG. 3, the projection 18 is provided over the entire circumference of the press-fitting jig facing surface 27, which is a disk surface and is on the outer peripheral side of the inner peripheral end of the inner ring 13. With this configuration, when the rolling bearing 5 is press-fitted into the shaft 9, the press-fitting jig 19 can apply a uniform load to the inner ring 13 and press the rolling bearing 5. Furthermore, the protrusion 18 does not necessarily need to be provided over the entire circumference of the press-fitting jig facing surface 27, and may be provided as long as the press-fitting jig 19 can apply an even load to the cylindrical plane of the inner ring 13 and press it. It may be provided in any way. For example, as shown in FIG. 4, the protrusions 18 are provided at at least two points symmetrically with respect to the center 30 of the disk surface of the press-fitting jig facing surface 27, or with the diameter 31 of the disk surface as the axis of symmetry. The structure may be such that they are provided in at least two locations along the line. With these configurations, when press-fitting the rolling bearing 5 into the shaft 9, the press-fitting jig 19 can always press only the inner ring 13 with a uniform load, and damage to the rolling elements 15 can be prevented.

Next, the effects of the protrusion 18 and the storage space 20 will be explained with reference to FIG.

The protruding portion 18 includes a press-fitting surface 29 that is parallel to the press-fitting jig facing surface 27 and facing the press-fitting surface of the press-fitting jig 19 at the protruding tip. In other words, the press-fitted surface 29 is a plane perpendicular to the cylindrical axis direction of the cylindrical inner ring 13. Since the protrusion 18 has the press-fitted surface 29, it becomes possible to further equalize the load from the press-fit jig 19 to the inner ring 13.

Furthermore, as mentioned in the problem section, conventionally there was a problem in that the rolling bearing 5 could not be press-fitted perpendicularly to the press-fitting jig facing surface 27 due to abrasion powder generated by friction with the shaft when the rolling bearing 5 was inserted.

To solve the above problem, the storage space 20 is provided as a concave space between the protrusion 18 and the shaft 9, and an opening in the concave shape faces the press-fitting jig 19. In other words, as shown in FIG. 5, even if abrasion powder is generated due to friction between the shaft 9 and the inner ring 13, and the abrasion powder also adheres to the press-fitting surface of the press-fitting jig 19, the abrasion powder on the press-fitting jig 19 The part to which the wear powder has adhered, in other words, the wear powder itself is stored in the storage space 20. Therefore, the press-fitting jig 19 can stably attach the rolling bearing 5 without being affected by wear particles, that is, without disturbing uniform pressing. Further, the protrusion 18 can prevent the abrasion powder stored in the storage space 20 from entering the inside of the rolling bearing 5.

With this configuration, it is possible to provide a rotor having a structure in which a rolling bearing can be stably mounted without being affected by abrasion powder generated by press-fitting the rolling bearing, and a motor equipped with the rotor.

(Embodiment 2)
A rotor and a motor according to Embodiment 2 of the present invention will be described with reference to FIG. 6. FIG. 6 is a sectional view showing the movement when the rolling bearing 5 according to the second embodiment is press-fitted into the housing 21.

The motor 1 according to the second embodiment is an outer rotor type. Therefore, the rotor 7 includes a housing 21, a rotor core 11, and a permanent magnet 8. For example, a blade is attached to the housing 21 and air is blown by rotating the housing 21.

In the rolling bearing 5 according to this embodiment, the outer ring 14 is a rotating ring that rotates together with the housing 21.

The outer ring 14 has a press-fitting jig facing surface 27, and includes a protrusion 18 protruding from the press-fitting jig facing surface 27 in the opposite direction to the press-fitting direction. In other words, the protrusion 18 protrudes in the axial direction of the cylindrical outer ring 14.

The protrusion 18 is provided to apply the load from the press-fit jig 19 only to the outer ring 14 without applying it to the inner ring 13. The protruding portion 18 is provided on the inner circumferential side of the disk surface of the press-fitting jig facing surface 27 with respect to the outer circumferential end (the pressure contact portion with the housing 21). In other words, the protrusion 18 is provided spaced apart from the housing 21 in the inner circumferential direction. The protrusion 18 is, for example, integrally molded with the outer ring 14. The protrusion 18 includes a press-fitting surface 29. Furthermore, the protrusion 18 includes a storage space 20 between it and the housing 21.

The storage space 20 is a space for storing wear powder generated when the rolling bearing 5 is press-fitted. The storage space 20 has a concave shape in cross-section surrounded by the protrusion 18, the press-fit jig facing surface 27, and the housing 21, and the opening in the concave shape faces the press-fit surface of the press-fit jig 19. provided.

With these configurations, similarly to the first embodiment, the press-fitting jig 19 can stably attach the rolling bearing 5 without being affected by wear powder. Further, the protrusion 18 can prevent the wear powder stored in the storage space 20 from entering the inside of the rolling bearing 5.

Next, the structure of the projection 18 will be explained in detail with reference to FIGS. 7 and 8. 7 and 8 are top views of the rolling bearing 5 according to the second embodiment, viewed from the press-fitting jig 19 side.

For example, as shown in FIG. 7, the protrusion 18 is provided over the entire circumference of the press-fitting jig facing surface 27, which is a disc surface and is on the inner peripheral side of the outer peripheral end of the outer ring 14. With this configuration, when the rolling bearing 5 is press-fitted into the housing 21, the press-fitting jig 19 can apply a uniform load to the outer ring 14 and press the rolling bearing 5. Furthermore, the protrusion 18 does not necessarily have to be provided over the entire circumference of the press-fitting jig facing surface 27, and may be provided in any way as long as the press-fitting jig 19 can press the outer ring 14 with an even load. It's okay. For example, as shown in FIG. 8, the protrusions 18 are arranged in at least two points symmetrically with respect to the center 30 of the disk surface of the press-fitting jig facing surface 27, or with the diameter 31 of the disk surface as the axis of symmetry. The structure may be such that they are provided in at least two locations along the line. With these configurations, when press-fitting the rolling bearing 5 into the housing 21, the press-fitting jig 19 can always press only the outer ring 14 with a uniform load, and damage to the rolling elements 15 can be prevented.

Therefore, even if the motor 1 is an outer rotor type, the rotor has a structure in which the rolling bearing can be stably mounted without being affected by the abrasion powder generated by press-fitting the rolling bearing, and the motor equipped with the rotor. can be provided.

A motor equipped with a rotor according to the present invention can be applied to, for example, a drive motor for a ventilation fan or the like.

1: Motor 2: Molded body 3: Stator 4: Winding 5: Rolling bearing 6: Bracket 7: Rotor 8: Permanent magnet 9: Shaft 10: E-ring 11: Rotor core 12: Connection member 13: Inner ring 14: Outer ring 15: Rolling element 16: Cage 17: Shield 18: Protrusion 19: Press-fitting jig 20: Storage space 21: Housing 22: Rotating shaft 23: Top surface of mold body 24: Insertion hole 26: U-shaped groove 27: Opposing press-fitting jig Surface 28: E-ring opposing surface 29: Press-fitted surface 30: Center 31: Diameter 102: Rolling bearing 103: Frame 112: Bearing housing 113: Open end 114: Positioning part

Claims (9)

A rotor comprising a rotor core, a shaft, and a rolling bearing inserted into the shaft,
The rolling bearing is
a cylindrical inner ring inserted into the shaft;
an outer ring disposed on the outer periphery of the inner ring;
A plurality of rolling elements are rotatably held between the outer circumference of the inner ring and the inner circumference of the outer ring,
The inner ring is
comprising a protrusion projecting in the axial direction of the cylindrical shape from at least one end of the cylindrical axial direction,
Between the protrusion and the shaft,
A rotor comprising a storage space for storing abrasion powder generated when the inner ring is inserted into the shaft. A rotor comprising a rotor core, a housing, and a rolling bearing inserted into the housing,
The rolling bearing is
a cylindrical outer ring inserted into the housing;
an inner ring disposed on the inner periphery of the outer ring;
A plurality of rolling elements are rotatably held between the outer circumference of the inner ring and the inner circumference of the outer ring,
The outer ring is
comprising a protrusion projecting in the axial direction of the cylindrical shape from at least one end of the cylindrical axial direction,
Between the protrusion and the housing,
A rotor comprising a storage space for storing abrasion powder generated when the outer ring is inserted into the housing. The protrusion is
The rotor according to claim 1 or 2, wherein the tip has a plane perpendicular to the cylindrical axis direction of the cylindrical shape. The protrusion is
4. The rotor according to claim 1, wherein at least two rotors are provided point-symmetrically with respect to the center of the disk surface in the cylindrical shape. The protrusion is
4. The rotor according to claim 1, wherein at least two rotors are provided line-symmetrically with respect to the diameter of the disk surface in the cylindrical shape. The protrusion is
The rotor according to claim 4 or 5, wherein the rotor is provided over the entire circumference of the disk surface in the cylindrical shape. The protrusion is
The rotor according to claim 1, wherein the rotor is integrally formed with the inner ring. The protrusion is
The rotor according to claim 2, wherein the rotor is integrally formed with the outer ring. A motor comprising the rotor according to any one of claims 1 to 8.

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