JP2020085178A - Bearing assembly, motor, and manufacturing method of motor - Google Patents

Abstract

To provide a bearing assembly which achieves stable rotation under a high temperature environment.SOLUTION: A bearing assembly 7 has: an outer holder 10 formed by a cylindrical member; an inner holder 20 formed by a cylindrical member and inserted into an inner periphery of the outer holder 10; a rolling bearing 30 which is fixed to an inner periphery of the inner holder 20 and in which a shaft member 4 is inserted to be fixed; and a preload spring 40 which is formed by a coil spring, held between a bottom surface 11 of the outer holder 10 and the rolling bearing 30, and applies a preload to the rolling bearing 30. Movement restriction mechanisms 12, 23, which restrict circumferential movement and axial movement of the inner holder 20 relative to the outer holder 10, are provided between the outer holder 10 and the inner holder 20.SELECTED DRAWING: Figure 2

Description

The present invention relates to a bearing assembly, a motor, and a motor manufacturing method.

Conventionally, there is known a motor in which a bearing assembly including a rolling bearing is arranged between a rotor portion and a stator portion. In such a motor, a bearing assembly in which a sleeve is provided so as to surround the bearing and the sleeve and the bearing are fixed with an adhesive is used in order to suppress co-rotation of the inner ring and the outer ring of the bearing (for example, See Patent Document 1).

JP, 2013-44435, A

However, adhesive properties are sensitive to temperature. Therefore, when the above bearing assembly is used in a motor that is intended to be used in a high temperature environment of 100° C. or higher, such as an in-vehicle motor, heat generation of the motor itself also affects the adhesive strength between the sleeve and the bearing. I have something to do. As a result, it becomes difficult to suppress co-rotation of the inner ring and the outer ring of the bearing, and there is a problem that it is difficult to realize stable rotation in a high temperature environment. Further, the motor provided with the above-mentioned bearing assembly has a problem that it is difficult to maintain stable rotation of the motor due to generation of vibrations and sounds, and the life of the motor is shortened.

Therefore, in view of the above problems, an object of the present invention is to provide a bearing assembly, a motor, and a method for manufacturing a motor, which realizes stable rotation even in a high-temperature environment, and thus realizes a long life. is there.

In order to solve the above problems, the bearing assembly of the present invention is an outer holder made of a cylindrical member, an inner holder made of a cylindrical member, inserted into the inner circumference of the outer holder, and fixed to the inner circumference of the inner holder. An outer holder having a rolling bearing in which the shaft member is inserted and fixed, and a coil spring, which is held between the bottom surface of the outer holder and the rolling bearing and which applies a preload to the rolling bearing. Between the inner holder and the inner holder, a movement restricting mechanism that restricts the movement of the inner holder with respect to the outer holder in the circumferential direction and the axial direction is provided.

In the bearing assembly of the present invention, it is possible to prevent the rolling bearing, that is, the inner holder from co-rotating with the relative rotation of the shaft member with respect to the outer holder without using an adhesive. As a result, stable rotation can be realized even in a high temperature environment. In addition, the outer holder can be held by the inner holder when the bearing assembly is assembled, and workability can be improved.

In the present invention, the movement restricting mechanism includes a first engaging portion formed on the outer holder and a second engaging portion formed on the inner holder and engaged with the first engaging portion in the circumferential direction and the axial direction. It consists of departments. In this case, the first engaging portion is a hole or a recess formed in the protruding wall that axially protrudes from the bottom surface of the outer holder, and the second engaging portion extends from the inner holder to the bottom surface of the outer holder. It is preferable that the locking claw is formed on a projecting piece that projects in the axial direction toward and engages with the hole or the recess by a snap fit. Furthermore, it is preferable that the projecting wall and the projecting piece extend axially inward in the radial direction of the pressurizing spring. With such a configuration, it becomes easy to arrange the pressurizing spring at an appropriate position when assembling the bearing assembly.

In the present invention, the movement restricting mechanism includes a first engagement portion formed on the outer holder and a second engagement portion formed on the inner holder and circumferentially engaged with the first engagement portion. Become. In this case, the first engaging portion is formed so as to penetrate from the outer peripheral surface to the inner peripheral surface of the outer holder, extends in the axial direction from the axial end surface of the outer holder, bends in the circumferential direction, and is further directed toward the axial end surface. It is preferable that the second engaging portion is a protruding portion that radially projects from the inner peripheral surface of the inner holder. Further, it is preferable that the outer holder has a cylindrical portion that projects in the axial direction from the bottom surface and extends radially inward of the pressurizing spring. With such a configuration, it becomes easy to arrange the pressurizing spring at an appropriate position when assembling the bearing assembly.

In the present invention, it is preferable that the rolling bearing is press fitted into the inner circumference of the inner holder. With such a configuration, it is possible to fix the rolling bearing and the inner holder without using an adhesive.

A motor of the present invention includes the above-mentioned bearing assembly, a rotor fixed to one of the outer holder and the shaft member, and a stator fixed to the other of the outer holder and the shaft member. .. With the motor of the present invention, it is possible to maintain stable rotation even in a high temperature environment, and in turn, it is possible to achieve a long service life of the motor.

In the present invention, the motor is formed of a cylindrical member, has a housing that fixes the outer holder to the inner circumference, an opening is formed in the bottom surface of the outer holder, and the inner peripheral surface of the housing has one of the outer holders. It is preferable that a communication groove extending in the axial direction from one end to the other end and communicating with the opening is formed. With such a configuration, even when air is sucked into the housing, it is possible to prevent such air from passing through the inside of the rolling bearing and axially flowing inside the outer holder. Further, when the housing is made of resin and the outer holder is fixed to the inner circumference of the housing by shrink fitting, it is possible to absorb the distortion due to the creep deformation of the housing.

Further, the motor manufacturing method of the present invention is characterized by including the steps of assembling the above-mentioned bearing assembly and fixing the assembled bearing assembly to the inner circumference of the housing made of a cylindrical member. .. In the motor manufacturing method of the present invention, since it is not necessary to fix the outer holder to the housing by insert molding in advance, workability in manufacturing the motor can be improved.

As described above, the bearing assembly of the present invention can realize stable rotation even in a high temperature environment. Further, in the motor of the present invention, it is possible to suppress co-rotation of the rolling bearing even under a high temperature environment and maintain stable rotation, and in turn, it is possible to extend the life of the motor.

It is a schematic sectional drawing of the motor provided with the bearing assembly of this invention. It is a schematic sectional view and a schematic exploded perspective view of a bearing assembly according to the first embodiment of the present invention. It is a schematic plan view of the housing which concerns on the 1st Embodiment of this invention. It is a schematic sectional drawing and a schematic disassembled perspective view of the bearing assembly which concerns on the 2nd Embodiment of this invention.

Hereinafter, embodiments of the present invention will be described with reference to the drawings. In the present specification, the bearing assembly of the present invention will be described by taking the case of being applied to a motor as an example. However, the present invention is not limited to this, and can be applied to a pump, a compressor, and the like. Further, as a motor to which the present invention is applied, as shown in the present specification, not only a motor in which a rotor is fixed to a shaft (shaft member) and a stator is fixed to an outer holder, but also a rotor is fixed to an outer holder. Needless to say, the stator may be fixed to the shaft.

(Overall structure of motor)
With reference to FIG. 1, the structure of a motor provided with the bearing assembly of the present invention will be described. FIG. 1 is a schematic cross-sectional view of a motor including a bearing assembly of the present invention, showing a cross section parallel to the rotation axis of the motor. Here, the case where the direction of the rotation axis R of the motor 1 is the vertical direction is shown, but this does not limit the posture of the motor 1 according to the present invention when it is used. Further, hereinafter, for convenience of description, the direction of the rotation axis R of the motor 1 is referred to as “axial direction”, and the radial direction and the circumferential direction with the rotation axis R as the center are simply referred to as “radial direction” and “circumferential direction”, respectively. I will call it. Although FIG. 1 shows a case where the bearing assembly according to the first embodiment is applied, the bearing assembly according to the second embodiment can be similarly applied.

The motor 1 has a rotor portion 2, a stator portion 3, a shaft 4, a housing 5, a flange 6, and a bearing assembly 7. The motor 1 is a molded motor in which a stator (stator portion 3) is integrally molded with a molding resin to form a motor frame (housing 5). Further, the motor 1 is an inner rotor type molded motor in which a stator is arranged inside the motor frame and a rotor (rotor portion 2) is arranged on the inner circumference of the stator.

(Rotor part)
The rotor portion 2 is a rotor that is fixed to a shaft 4 that is a cylindrical member made of metal and that rotates together with the shaft 4, and has a rotor magnet 2a, a magnet cover 2b, and a plate 2c.

The rotor magnet 2a is a permanent magnet made of ferrite and is arranged around the shaft 4 along the circumferential direction. A magnetic pole surface facing the stator portion 3 in the radial direction is formed on the outer peripheral side of the rotor magnet 2a, and the magnetic pole surface is alternately magnetized in the circumferential direction with N poles and S poles. The magnet cover 2b is provided so as to cover the rotor magnet 2a and prevents the rotor magnet 2a made of ferrite from scattering. Plates 2c made of a non-magnetic material such as stainless steel are provided on both sides in the axial direction. An elastic portion (not shown in detail) such as a disc spring is formed on the surface of the plate 2c facing the magnet cover 2b. By pressing the magnet cover 2b against the plate 2c, the rotor magnet 2a is securely fastened by the urging force of the elastic portion. The plate 2c has a function of adjusting the rotor balance of the motor 1 after the rotor unit 2 is assembled. Specifically, the rotor balance is measured, and holes are formed in the plate 2c for balance adjustment.

(Stator part)
The stator portion 3 is arranged in a cylindrical shape around the rotor portion 2, and the stator portion 3 that is a stator that functions as an armature of the motor 1 has a stator core 3a, a coil 3b, and an insulator 3c. .. The stator portion 3 is made of a heat-resistant insulating resin such as polyphenylene sulfide (PPS) with its inner peripheral surface exposed so that the inner peripheral surface faces the outer peripheral surface of the rotor magnet 2a with a space therebetween. It is embedded inside the housing 5.

The stator core 3a is made of a laminated steel plate in which a plurality of magnetic steel plates such as silicon steel plates are laminated in the axial direction. Each magnetic steel plate has an annular portion and a plurality of magnetic pole teeth projecting radially inward from the annular portion. That is, the inner peripheral surface of the stator portion 3 is formed by the end surfaces of the magnetic pole teeth. The coil 3b is composed of a winding wound around the magnetic pole teeth of the stator core 3a via the insulator 3c. The insulator 3c is made of an insulating resin such as PPS and electrically insulates the stator core 3a and the coil 3b.

Thus, by supplying the drive current to the coil 3b, magnetic flux is generated in the radial direction along the magnetic pole teeth that are the magnetic core. As a result, circumferential torque is generated between the magnetic pole teeth and the rotor magnet 2a, and the rotor 2 part rotates together with the shaft 4 with the central axis of the shaft 4 as the rotation axis R.

The housing 5 has a bottomed cylindrical shape opening to the output side of the motor 1, and the rotor portion 2 is housed in the internal space thereof. The housing 5 is composed of two mold parts 51 and 52, and one mold part 51 is formed by so-called insert molding. That is, it is formed by inserting the stator part 3 into the mold and then injecting resin into the mold to integrate the stator part 3 and the resin. The flange 6 is attached to the housing 5 so as to cover the opening of the housing 5, and holds the second rolling bearing 6.

(First embodiment)
The configuration of the bearing assembly according to the first embodiment of the present invention will be described with reference to FIG. FIG. 2A is a schematic cross-sectional view of the bearing assembly of the present embodiment taken along the axial direction, and FIG. 2B is a schematic exploded perspective view of the bearing assembly of the present embodiment. Note that the illustration of the preload spring is omitted in FIG. Bearing assemblies are used to provide sliding or rotary motion, and are typically used to support and rotate rotatable shaft elements with minimal friction.

The bearing assembly 7 supports the rotor portion 2 and the stator portion 3 of the motor 1 so as to be rotatable relative to each other, and includes an outer holder 10, an inner holder 20, and a first rolling bearing (hereinafter, simply referred to as “rolling bearing”). ”), a pressurizing spring 40, and a movement restricting mechanism 50 (first engaging portion 12 and second engaging portion 23).

The outer holder 10 is a bottomed cylindrical member that extends in the axial direction, and is fixed to the inner periphery of the housing 5 on the counter output side of the motor 1 by press fitting or shrink fitting. The inner holder 20 is a cylindrical member that extends in the axial direction, and is inserted into the inner circumference of the outer holder 10. A rubber sleeve 22 is provided on the outer peripheral surface 21 of the inner holder 20 for vibration damping, sound absorption, and axial alignment of the shaft 4. An O-ring may be provided instead of the rubber sleeve 22. The rolling bearing 30 is press-fitted and fixed to the inner circumference of the inner holder 20.

The rolling bearing 30 is a ball bearing that includes an inner ring 30a, two or more rolling elements 30b, and an outer ring 30c, and rotatably supports the shaft 4. The inner ring 30a and the outer ring 30c are both metal annular members, and the outer ring 30b is arranged radially outside the inner ring 30a. The rolling element 30b is a spherical member, and is arranged between the outer peripheral surface of the inner ring 30a and the inner peripheral surface of the outer ring 30c. The shaft 4 is press-fitted and fixed to the inner circumference of the rolling bearing 30.

The pressurizing spring 40 is a coil spring, and is arranged between the bottom surface 11 of the outer holder 10 and the inner holder 20. The preload spring 40 applies a preload to the rolling bearing 30 by axially pressing the outer ring 30c through the annular bottom surface 24 of the inner holder 20 against the inner ring 30a of the rolling bearing 30 fixed to the shaft 4. There is.

The movement restricting mechanism 50 is formed on the first engaging portion 12 formed on the outer holder 10 and the inner holder 20, and is a second engaging portion that engages with the first engaging portion 12 in the circumferential and axial directions. It is composed of a joint portion 23. That is, the outer holder 10 is formed with a projecting wall 14 that projects in the axial direction from the peripheral edge of the opening 13 formed in the annular bottom surface 11, and the projecting wall 14 has a hole portion that opens radially inward ( A first engaging portion) 12 is formed. Further, the inner holder 20 is formed with a projecting piece 25 that projects in the axial direction toward the bottom surface 11 of the outer holder 10, and the projecting piece 25 is formed with a locking claw (second engaging portion) 23. There is. The protruding piece 25 is formed so as to be elastically deformable in the radial direction, and the locking claw 23 engages with the hole 12 by a snap fit when the inner holder 20 is inserted into the inner periphery of the outer holder 10. The movement restricting mechanism 50 restricts the circumferential movement and the axial movement of the inner holder 20 with respect to the outer holder 10.

Here, the communication groove formed around the outer holder will be described with reference to FIGS. 1 and 3. FIG. 3 is a schematic plan view of the housing of this embodiment as seen from the output side of the motor.

When a temperature difference suddenly occurs between the output side and the counter output side of the motor 1, air may be sucked into the housing 5 from the output side of the motor 1 toward the counter output side. When the sucked air passes through the inside of the rolling bearing 30, foreign matter may enter the rolling bearing 30 or the lubricating oil of the rolling bearing may be discharged, resulting in a shorter life of the rolling bearing 30. There is a risk. Therefore, on the inner peripheral surface 5a of the housing 5 to which the outer holder 10 is fixed, a first communication groove 5b extending axially from one end of the outer holder 10 to the other end is formed. Further, the bottom surface 5c of the housing 5 is formed with a second communication groove 5d connected to the first communication groove 5b. As a result, even if the air is sucked in as described above, the air will flow from the communication grooves 5b and 5d to the inside of the outer holder 10 through the opening 13 and pass through the inside of the rolling bearing 30. There is no.

The formation of such communication grooves 5b and 5d is realized by eliminating the need to integrally fix the outer holder 10 to the housing 5 by insert molding. This is possible because the inner holder with respect to the outer holder 10 can be formed. This is because the movement of 20 in the axial direction is restricted. That is, by restricting the axial movement of the inner holder 20 with respect to the outer holder 10, the outer holder 10 can be held by the inner holder 20 when the bearing assembly 7 is assembled, and the outer holder 10 is inserted. By molding, it is not necessary to integrally fix the housing 5. As a result, it becomes possible to form the communication grooves 5b and 5d on the inner peripheral surface 5a and the bottom surface 5c of the housing 5. The elimination of insert molding of the outer holder 10 leads to a reduction in the number of parts to be inserted and also leads to an improvement in workability of insert molding.

When the outer holder 10 is fixed to the inner circumference of the housing 5 by shrink fitting, a constant stress is continuously applied to the inner circumference of the housing 5 by the outer holder 10. Therefore, in a high temperature environment, creep deformation occurs in the housing 5, which causes a gap between the housing 5 and the outer holder 10, so that the outer holder 10 moves relative to the housing 5 as the shaft 4 rotates. There is a risk of idling. The first communication groove 5b also has a function of absorbing such strain due to creep deformation of the housing 5.

Note that when the outer holder 10 is not inserted to the bottom surface 5c of the housing 5, that is, there is a gap between the outer holder 10 and the bottom surface 5c of the housing 5 in the axial direction, and the first communication groove is provided through the gap. When 5b communicates with the opening 13 of the outer holder 10, the second communication groove 5d may be omitted.

(Main effects of the first embodiment)
As described above, the bearing assembly 7 of the present embodiment includes the outer holder 10 formed of a cylindrical member, the inner holder 20 formed of the cylindrical member and inserted into the inner periphery of the outer holder 10, and the inner holder 20. A preload that is fixed to the circumference and is formed of a coil spring and a shaft 4 is inserted and fixed, and is held between the bottom surface 11 of the outer holder 10 and the rolling bearing 30 to apply a preload to the rolling bearing 30. A spring 40 and a movement restricting mechanism 50 (first engagement member) that restricts the circumferential movement and the axial movement of the inner holder 20 with respect to the outer holder 10 between the outer holder 10 and the inner holder 20. A joining portion 12 and a second engaging portion 23) are provided. This makes it possible to prevent the rolling bearing 30, that is, the inner holder 10 from rotating together with the relative rotation of the shaft 4 with respect to the outer holder 20, without using an adhesive. As a result, stable rotation can be realized even in a high temperature environment. In addition, the outer holder can be held by the inner holder when the bearing assembly is assembled, and the workability can be improved.

In the present embodiment, the movement restricting mechanism 50 is formed on the first engaging portion 12 formed on the outer holder 10 and the inner holder 20, and engages with the first engaging portion 12 in the circumferential direction and the axial direction. And the second engaging portion 23. Therefore, it becomes possible to form the movement restricting mechanism 50 with a simple shape.

In the present embodiment, the projecting wall 14 of the outer holder 10 and the projecting piece 25 of the inner holder 20 respectively extend inward in the radial direction of the pressurizing spring 40 in the axial direction. Therefore, it becomes easy to dispose the pressurizing spring 40 at an appropriate position when the bearing assembly 7 is assembled.

In this embodiment, the rolling bearing 30 is press-fitted into the inner circumference of the inner holder 20. With such a configuration, the rolling bearing 30 and the inner holder 20 can be fixed without using an adhesive.

Further, in the motor 1 of the present embodiment, since the bearing assembly 7 described above is provided, it is possible to maintain stable rotation even in a high temperature environment (for example, 100° C. or higher), and thus the motor 1 It is possible to realize a long life.

The motor 1 according to the present embodiment is formed of a cylindrical member, has a housing 5 that fixes the outer holder 10 to the inner periphery, an opening 13 is formed in the bottom surface 11 of the outer holder 10, and the inner peripheral surface 5 a of the housing 5 is formed. A communication groove 5b is formed in the outer holder 10 so as to extend in the axial direction from one end of the outer holder 10 to the other end and communicate with the opening 13. With such a configuration, even when air is sucked into the housing 5, it is possible to suppress such air from passing through the inside of the rolling bearing 30 and axially flowing inside the outer holder 10. become. Furthermore, when the housing 5 is made of resin and the outer holder 10 is fixed to the inner circumference of the housing 5 by shrink fitting, it is possible to absorb the distortion due to the creep deformation of the housing 5.

Further, the method for manufacturing the motor 1 of the present embodiment includes a step of assembling the bearing assembly 7 described above and a step of fixing the assembled bearing assembly 7 to the inner circumference of the housing 5 made of a cylindrical member. I'm out. In such a manufacturing method, since it is not necessary to fix the outer holder 10 to the housing 5 by insert molding in advance, workability in manufacturing the motor 1 can be improved.

(Modification of the first embodiment)
The above-described embodiment is an example of a preferred mode of the present invention, but the present invention is not limited to this, and various modifications can be made to the above-described embodiment without departing from the scope of the present invention. Is possible.

The hole 12 and the locking claw 23 have a specific configuration as long as they engage with each other by a snap fit to restrict the circumferential movement and the axial movement of the inner holder 20 with respect to the outer holder 10. It is not limited to. For example, the number of the holes 12 or the protruding walls 14 may be one or three or more, and accordingly, the number of the locking claws 23 or the protruding pieces 25 may be one or three. It may be more than. Further, the locking claw 23 may engage with the hole 12 from the outside in the radial direction, instead of engaging with the hole 12 from the inside in the radial direction. There may be provided a recess not penetrating in the thickness direction. Further, the outer holder 10 may be formed with engaging claws, and the inner holder 20 may be formed with holes or recesses.

In this embodiment, a ball bearing is used as the rolling bearing 30, but a rolling bearing other than the ball bearing, for example, a tapered roller bearing may be used. Further, the fixing of the shaft 4 is not limited to press fitting, and the shaft 4 inserted in the rolling bearing 30 may be fixed by using another method such as bolting.

(Second embodiment)
FIG. 4A is a schematic cross-sectional view taken along the axial direction of the bearing assembly according to the second embodiment of the present invention, and FIG. 4B is a schematic exploded perspective view of the bearing assembly according to the present embodiment. It is a figure. Note that the preload spring is not shown in FIG. Hereinafter, regarding the same configuration as the first embodiment, the same reference numerals are given to the drawings, the description thereof will be omitted, and only the configuration different from the first embodiment will be described.

The movement restricting mechanism 50 according to the second embodiment includes a first engaging portion 15 formed on the outer holder 10 and a second engaging portion 26 formed on the inner holder 20. Specifically, the movement restricting mechanism 50 includes a locking groove (first engaging portion) 15 formed by penetrating from the outer peripheral surface 16 to the inner peripheral surface 17 of the outer holder 10 and the inner peripheral surface of the inner holder 20. It is composed of a convex portion (second engaging portion) 26 that projects radially from the surface 21. The locking groove 15 extends in the axial direction from the axial end surface 18 of the outer holder 10, is bent in the circumferential direction, and is further bent in the axial direction toward the axial end surface 18. The convex portion 26 is inserted along the locking groove 15, and engages with the locking groove 15 in the circumferential direction and the axial direction at the tip thereof. With such a configuration, circumferential movement and axial movement of the inner holder 20 with respect to the outer holder 10 are restricted. In addition, in this embodiment, instead of the protruding wall 14 and the protruding piece 25 of the first embodiment not being provided, the outer holder 10 protrudes axially from the bottom surface 11 and extends radially inward of the pressurizing spring 40. It has a cylindrical portion 19 that extends and forms the opening 13. The pressurizing spring 40 is housed between the cylindrical portion 19 and the inner peripheral surface 17 of the outer holder 10.

(Main effects of the second embodiment)
As described above, the bearing assembly 7 of the present embodiment includes the outer holder 10 formed of a cylindrical member, the inner holder 20 formed of the cylindrical member and inserted into the inner periphery of the outer holder 10, and the inner holder 20. A preload that is fixed to the circumference and is formed of a coil spring, which is fixed by inserting the shaft 40, and is held between the bottom surface 11 of the outer holder 10 and the rolling bearing 30 to apply a preload to the rolling bearing 30. A spring 40 and a movement restricting mechanism 50 (first engagement member) that restricts the circumferential movement and the axial movement of the inner holder 20 with respect to the outer holder 10 between the outer holder 10 and the inner holder 20. A mating portion 15 and a second engaging portion 26) are provided. This makes it possible to prevent the rolling bearing 30, that is, the inner holder 10 from rotating together with the relative rotation of the shaft 4 with respect to the outer holder 20, without using an adhesive. As a result, stable rotation can be realized even in a high temperature environment. In addition, the outer holder can be held by the inner holder when the bearing assembly is assembled, and the workability can be improved.

In the present embodiment, the movement restricting mechanism 50 is formed on the first engaging portion 15 formed on the outer holder 10 and the inner holder 20, and engages with the first engaging portion 15 in the circumferential direction and the axial direction. And the second engaging portion 26. Therefore, it becomes possible to form the movement restricting mechanism 50 with a simple shape.

In the present embodiment, the outer holder 10 has a cylindrical portion 19 which projects axially from the bottom surface 11 and extends radially inward of the pressurizing spring 40. Therefore, it becomes easy to dispose the pressurizing spring 40 at an appropriate position when the bearing assembly 7 is assembled.

Further, in the motor 1 of the present embodiment, since the bearing assembly 7 described above is provided, it is possible to maintain stable rotation even in a high temperature environment (for example, 100° C. or higher), and thus the motor 1 It is possible to realize a long life.

(Modification of the second embodiment)
The above-described embodiment is an example of a preferred mode of the present invention, but the present invention is not limited to this, and various modifications can be made to the above-described embodiment without departing from the scope of the present invention. Is possible.

The structure of the locking groove 15 and the convex portion 26 is limited to a specific structure as long as they are engaged with each other and restrict the circumferential movement and the axial movement of the inner holder 20 with respect to the outer holder 10. Not something. For example, the number of locking grooves 15 may be one or three or more. In this case, the number of convex portions 26 does not necessarily have to be the same as the number of locking grooves 15, and It may be less than 15. Further, the length and width of the locking groove 15 are not particularly limited as long as the locking groove 15 accommodates the convex portion 26 and exerts a desired function. For example, a part of the locking groove 15 is provided. May be extended in the axial direction so as to function as an air passage similarly to the communication groove 5b of the first embodiment.

1 Motor 2 Rotor Part 2a Rotor Magnet 2b Magnet Cover 2c Plate 3 Stator Part 3a Stator Core 3b Coil 3c Insulator 4 Shaft 5 Housing 51, 52 Mold Part 6 Flange 7 Bearing Assembly 8 Second Rolling Bearing 10 Outer Holder 11 Bottom 12 Hole Part 13 Opening Part 14 Projecting Wall 15 Locking Groove 16 Outer Surface 17 Inner Surface 18 Axial End Surface 19 Cylindrical Part 20 Inner Holder 21 Outer Surface 22 Rubber Sleeve 23 Locking Claw 24 Bottom 25 Projecting Piece 26 Convex 30 First Rolling bearing (rolling bearing)
30a Inner ring 30b Ball 30c Outer ring 40 Preload spring 50 Movement restriction mechanism

Claims (10)

An outer holder made of a cylindrical member,
An inner holder made of a cylindrical member and inserted into the inner circumference of the outer holder,
A rolling bearing fixed to the inner circumference of the inner holder, and having a shaft member inserted and fixed;
A coil spring, which is held between the bottom surface of the outer holder and the rolling bearing, and which has a preload spring for applying a preload to the rolling bearing,
A bearing assembly, wherein a movement restricting mechanism that restricts circumferential movement and axial movement of the inner holder with respect to the outer holder is provided between the outer holder and the inner holder. The movement restricting mechanism includes a first engaging portion formed on the outer holder and a second engaging portion formed on the inner holder and engaged with the first engaging portion in a circumferential direction and an axial direction. The bearing assembly according to claim 1, wherein the bearing assembly comprises: The first engaging portion is a hole or a recess formed in a protruding wall that axially protrudes from the bottom surface of the outer holder, and the second engaging portion extends from the inner holder to the outer holder. 3. The bearing assembly according to claim 2, wherein the bearing assembly is a locking claw that is formed on a projecting piece that projects in the axial direction toward the bottom surface and that engages with the hole or the recess by a snap fit. The bearing assembly according to claim 3, wherein each of the projecting wall and the projecting piece extends axially inward in a radial direction of the pressurizing spring. The first engaging portion is formed so as to penetrate from the outer peripheral surface to the inner peripheral surface of the outer holder, extends in the axial direction from the axial end surface of the outer holder, bends in the circumferential direction, and further extends to the axial end surface. It is a locking groove which bends toward the axial direction toward, and the said 2nd engaging part is a convex part which protrudes radially from the inner peripheral surface of the said inner side holder, The Claim 2 characterized by the above-mentioned. Bearing assembly. The bearing assembly according to claim 5, wherein the outer holder has a cylindrical portion that projects axially from the bottom surface and extends radially inward of the pressurizing spring. The bearing assembly according to any one of claims 1 to 6, wherein the rolling bearing is press-fitted into an inner circumference of the inner holder. A bearing assembly according to any one of claims 1 to 7, a rotor fixed to one of the outer holder and the shaft member, and a stator fixed to the other of the outer holder and the shaft member. A motor characterized by being provided. A cylindrical member, the outer holder has a housing fixed to the inner periphery,
An opening is formed in the bottom surface of the outer holder, and an inner peripheral surface of the housing has a communication groove that extends in the axial direction from one end of the outer holder to the other end and communicates with the opening. The motor according to claim 8, wherein the motor is formed. A manufacturing method for manufacturing the motor according to claim 8 or 9,
Assembling the bearing assembly,
And a step of fixing the assembled bearing assembly to an inner circumference of a housing made of a cylindrical member.

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