Rolling bearing and rotating apparatus

Abstract

Provided is a rolling bearing capable of suppressing the occurrence of slippage of a raceway ring. A rolling bearing (1) is provided with: an inner ring (10) and an outer ring (20) disposed coaxially with each other; and a rolling body (30) disposed between the inner ring (10) and the outer ring (20). The outer ring (20) is attached to the base (120). The outer ring (20) is provided with a resin cover (60) having a fitting part (27) that is fitted to the base part (120) so as not to rotate relative to the base part (120).

Description

Technical Field

[0001] The invention relates to rolling bearings and rotating equipment. Background Art

[0002] Generally speaking, a rolling bearing comprises: an outer ring and an inner ring, which are arranged on the same axis; a plurality of rolling elements, which are arranged between the inner ring and the outer ring; and a retainer, which holds each rolling element in a rolling manner so that the plurality of rolling elements are evenly arranged in the circumferential direction. Various rolling bearings are known according to the type of load supported (radial load, axial load, etc.) or the purpose, and are installed in various rotating devices such as fan motors for use. In particular, ball bearings that use balls as rolling elements are suitably used in rotating devices having a shaft portion of a rotating body that rotates at high speed.

[0003] With the high-speed rotation of rotating equipment in recent years, the phenomenon of slippage between the assembled component equipped with the raceway ring and the mounting surface of the raceway ring due to the associated rotation of the raceway ring has become a problem. If the raceway ring slips, noise or wear powder may be generated, or the sliding part may heat up. In this case, the transfer surface (transfer surface) of the raceway ring and the ball may be damaged due to the invasion of wear powder, or the internal grease of the rolling bearing may deteriorate due to the heat of the sliding part, and the life of the rolling bearing may be reduced. The same undesirable conditions may also occur in the case of creep or micro-vibration wear.

[0004] In order to suppress the occurrence of the above-mentioned inconvenience, there is a technique of applying grease to the mounting surface of a rolling bearing (for example, see Patent Document 1). This can reduce the friction coefficient on the mounting surface and suppress creep. Prior Art Literature Patent Literature

[0005] Patent Document 1: Japanese Patent Application Publication No. 2013-60990. Summary of the invention Problems to be solved by the invention

[0006] However, even if grease is applied to the mounting surface of the raceway ring, it is not enough to suppress the slip of the raceway ring itself. In addition, if the grease applied to the mounting surface of the raceway ring is used up, there is a problem that the above-mentioned undesirable conditions may occur. Therefore, in rotating equipment equipped with rolling bearings, there is still the problem of suppressing the slip of the raceway ring of the rolling bearing.

[0007] Therefore, the present invention provides a rolling bearing capable of suppressing the occurrence of slippage of a raceway ring, and a rotating device including the rolling bearing. Solutions to Solve Problems

[0008] The rolling bearing involved in the first embodiment of the present invention comprises: an inner ring and an outer ring, which are arranged coaxially with each other; and a rolling element, which is arranged between the aforementioned inner ring and the aforementioned outer ring. The rolling bearing is a rolling bearing in which one of the aforementioned inner ring and the aforementioned outer ring has a raceway ring assembled on an assembled component, and the aforementioned one raceway ring has a resin portion, and the aforementioned resin portion has an engaging portion that is engaged with the aforementioned assembled component in a manner that cannot rotate relative to each other.

[0009] According to the first scheme, the rotation of one raceway ring relative to the assembled component can be restricted. Furthermore, the fitting portion is provided in the resin portion of one raceway ring, so compared with the case where the fitting portion is provided in the metal component of one raceway ring, the processability of one raceway ring is improved, and the decrease in the roundness of one raceway ring due to the formation of a complex shape can be suppressed. Therefore, the decrease in the precision of the rolling bearing can be suppressed, and at the same time, the occurrence of slippage of the raceway ring can be suppressed.

[0010] A rolling bearing according to a second aspect of the present invention may be the rolling bearing according to the first aspect, wherein the one raceway ring has an end surface facing outward in the axial direction, and the fitting portion is provided on the end surface.

[0011] If one of the raceways is an outer ring and a fitting portion is provided on the outer peripheral surface as the mounting surface of the outer ring, the processability of the outer peripheral surface may be reduced when the outer peripheral surface is formed, and the dimensional accuracy of the outer peripheral surface may be deteriorated. The same is true when one of the raceways is an inner ring. According to the second scheme, the dimensional accuracy of the mounting surface of one of the raceways can be suppressed from being deteriorated. Therefore, the precision of the rolling bearing can be suppressed from being reduced.

[0012] A rolling bearing according to a third aspect of the present invention may be the rolling bearing according to the first aspect, wherein the one raceway ring has a peripheral surface facing the mounted component in the radial direction, and the fitting portion is provided on the peripheral surface.

[0013] According to the third aspect, during the process of assembling the rolling bearing to the mounted component, the engagement state of the engagement portion and the engaged portion of the mounted component can be visually confirmed. Therefore, a rolling bearing having excellent operability when assembled to the mounted component can be obtained.

[0014] The rolling bearing involved in the fourth embodiment of the present invention may be a rolling bearing involved in any one of the first to third embodiments, wherein the aforementioned one raceway ring has a metal raceway ring body having a raceway surface for the aforementioned rolling element to roll on, and the aforementioned resin portion is a resin cover covering the aforementioned raceway ring body.

[0015] According to the fourth scheme, the contact portion of one raceway ring with the rolling element is formed of a metal material, and thus, by providing a resin portion, it is possible to suppress a decrease in the durability of the rolling bearing. In addition, the resin portion and the raceway ring body can be integrally embedded and molded, and thus, it is possible to suppress the positional deviation of the resin portion relative to the raceway ring body and form one raceway ring with good precision. Furthermore, the raceway ring body is covered with a resin cover, and thus, electrical corrosion can be prevented.

[0016] The rolling bearing according to the fifth aspect of the present invention may be the rolling bearing according to the fourth aspect, wherein the resin cover is arranged only on one side in the axial direction of the raceway surface of the one raceway ring relative to the axial center position.

[0017] According to the fifth aspect, compared with a configuration in which the resin cover is arranged over the entire axial length of one raceway ring, the amount of resin used in the resin cover can be reduced, thereby reducing the manufacturing cost.

[0018] A rolling bearing according to a sixth aspect of the present invention may be the rolling bearing according to any one of the first to third aspects, wherein the entirety of the one raceway ring is the resin portion.

[0019] According to the sixth aspect, compared with a case where a portion of a raceway ring is made of metal, the raceway ring can be easily formed, and the productivity of the raceway ring can be improved. Furthermore, it is possible to suppress the electric current flowing inside the rolling bearing and causing electrical corrosion in the rolling bearing.

[0020] A rolling bearing according to a seventh aspect of the present invention may be the rolling bearing according to the sixth aspect, wherein the other raceway ring of the inner ring and the outer ring is made of resin.

[0021] According to the seventh scheme, compared with the case where a part of the other raceway is made of metal, the other raceway is easier to form, and the productivity of the other raceway can be improved. Furthermore, by forming the inner ring and the outer ring from a resin material that absorbs less moisture, the dimensional change of the inner ring and the outer ring due to moisture absorption is suppressed. Therefore, it can be used as a rolling bearing suitable for use in water.

[0022] A rolling bearing according to an eighth aspect of the present invention may be the rolling bearing according to any one of the first to seventh aspects, wherein the resin portion includes potassium titanate whiskers.

[0023] According to the eighth aspect, the resin portion can be made into a component having excellent wear resistance and surface smoothness. In addition, compared with the case where the resin portion includes glass fiber or carbon fiber as a reinforcing material, the processability when the resin portion is formed by cutting or grinding can be improved.

[0024] The rolling bearing involved in the 9th scheme of the present invention can also be a rolling bearing involved in any one of the above-mentioned 1st scheme to 8th scheme, wherein the resin material forming the above-mentioned resin part is formed by one or more of polybutylene terephthalate, polyphenylene sulfide and polyetheretherketone.

[0025] According to the ninth aspect, it is possible to suppress moisture absorption of the resin portion and dimensional change of one raceway due to moisture absorption. Therefore, a rolling bearing suitable for use in water can be obtained.

[0026] The rotating device involved in the tenth embodiment of the present invention comprises: the rolling bearing involved in any one of the above-mentioned embodiments 1 to 9; the aforementioned assembled component, which has an engaged portion engaged with the aforementioned engaging portion; and a rotating body, which is supported on the aforementioned assembled component via the aforementioned rolling bearing and is configured in a manner capable of rotating relative to the aforementioned assembled component.

[0027] According to the tenth aspect, it is possible to provide a rotating device in which slippage of the raceway ring of the rolling bearing is suppressed.

[0028] The rotating device involved in the 11th scheme of the present invention comprises: the rolling bearing involved in the above-mentioned 4th scheme or 5th scheme; the aforementioned assembled component, which has an engaged portion engaged with the aforementioned engaging portion; a rotating body, which is supported on the aforementioned assembled component via the aforementioned rolling bearing and is configured in a manner capable of rotating relative to the aforementioned assembled component; and a force-applying component, which applies force to one side of the aforementioned inner ring and the other raceway ring of the aforementioned outer ring along the axial direction, and the aforementioned resin cover has a contact portion relative to the aforementioned assembled component only at a position of the aforementioned raceway surface that is closer to the other side of the aforementioned axial direction than the center position in the aforementioned axial direction.

[0029] In the 11th scheme, the rolling element is subjected to the force of the force-applying member and contacts a portion of the raceway surface that is closer to the axial side than the axial center position. Here, if the resin cover is sandwiched between the contact point of the raceway surface with the rolling element and the assembled component in the radial direction, when the resin cover generates strain and the strain is transmitted to the raceway ring body, there is a possibility that the contact point of the raceway surface with the rolling element changes and the rolling bearing may malfunction. According to the 10th scheme, the resin cover does not contact the assembled component at a position of the raceway surface that is closer to the axial side than the axial center position, so even if strain is generated in the resin cover near the contact point between the outer ring and the rolling element, the strain can be prevented from affecting the raceway ring body. Therefore, it is possible to suppress the change of the contact point of the raceway surface with the rolling element and the malfunction of the rolling bearing. Effects of the Invention

[0030] According to the present invention, it is possible to suppress the occurrence of slippage of the raceway ring. BRIEF DESCRIPTION OF THE DRAWINGS

[0031] Figure 1 It is a longitudinal sectional view showing the fan motor according to the embodiment. Figure 2 It is a top view of the rolling bearing according to the first embodiment. Figure 3 is a longitudinal sectional view of a rolling bearing according to the first embodiment, showing Figure 2 The cross section on line III-III. Figure 4 It is a top view of the outer ring of the first embodiment. Figure 5 is a cross-sectional view of the fan motor of the first embodiment, which is equivalent to Figure 1 A portion of the V portion is shown enlarged. Figure 6 is a longitudinal sectional view of a rolling bearing according to the second embodiment, which is equivalent to Figure 3 . Figure 7 It is a top view of the outer ring of the second embodiment. Figure 8 It is a top view of the outer ring of the third embodiment. Figure 9 is a cross-sectional view of a fan motor according to a third embodiment, which is equivalent to Figure 5 . Figure 10 is a cross-sectional view of a fan motor according to a fourth embodiment, which is equivalent to Figure 5 . DETAILED DESCRIPTION

[0032] Hereinafter, embodiments of the present invention will be described based on the accompanying drawings. In the following description, components having the same or similar functions are denoted by the same reference numerals, and repeated descriptions of these components may be omitted.

[0033] Figure 1 This is a longitudinal sectional view showing a fan motor according to an embodiment. Figure 1The fan motor 100 shown is an example of a rotating device. The fan motor 100 includes: a rotating body 110 having a shaft 111; a base 120 that supports the rotating body 110; a driving unit 130 that rotates the rotating body 110 relative to the base 120; and a pair of rolling bearings 1 that are mounted on the base 120 and support the shaft 111 in a rotatable manner. In the following description, the rolling bearing 1 is sometimes referred to as just bearing 1. In addition, in the present embodiment, the direction in which the central axis O of the shaft 111 of the rotating body 110 extends is referred to as the axial direction, the direction that is orthogonal to the central axis O and extends radially from the central axis O is referred to as the radial direction, and the direction that surrounds the central axis O is referred to as the circumferential direction. In addition, one of the directions that are parallel to the axial direction and point in opposite directions to each other is defined as the upper direction, and the other is defined as the lower direction.

[0034] The base 120 has a cylindrical portion 121 extending in the axial direction. The shaft portion 111 of the rotating body 110 is inserted into the cylindrical portion 121 . The rotating body 110 is arranged above the base 120. The rotating body 110 includes a shaft 111 and a fan 112 connected to the shaft 111 outside the cylinder 121. The fan 112 is fixed to the upper end of the shaft 111. The fan 112 includes: a flange 113 extending outward in the radial direction from the upper end of the shaft 111 and extending throughout the entire circumferential direction; a peripheral wall 114 extending downward from the outer peripheral edge of the flange 113 as a whole; and a plurality of blades 115 arranged at intervals in the circumferential direction outside the radial direction of the peripheral wall 114. The peripheral wall 114 surrounds the cylinder 121 throughout the entire circumference in a state of being spaced apart in the radial direction relative to the cylinder 121.

[0035] The driving unit 130 is a motor and includes a stator 131 having a coil and a rotor 132 having a magnet. The stator 131 is fixed to the base 120 outside the shaft 111. The rotor 132 is fixed to the peripheral wall 114 of the fan 112 outside the stator 131 in the radial direction.

[0036] The pair of bearings 1 are respectively interposed between the inner peripheral surface of the cylinder portion 121 and the outer peripheral surface of the shaft portion 111. Each bearing 1 is a ball bearing. The pair of bearings 1 are coaxially arranged with each other. The pair of bearings 1 are arranged side by side with a gap in the axial direction.

[0037] A pair of bearings 1 is a first bearing 1A and a second bearing 1B. The first bearing 1A is inserted into the cylinder 121 from the rotating body 110 side. The end surface of the first bearing 1A facing downward from the outer ring 20 contacts the step surface 122 of the inner circumferential surface of the cylinder 121. The first bearing 1A contacts the force member 101. The force member 101 is a coil spring. The force member 101 is arranged on the opposite side of the step surface 122 with the first bearing 1A clamped. The force member 101 is inserted into the shaft 111 of the rotating body 110 and is arranged coaxially with the center axis O. The force member 101 is between the inner ring 10 of the first bearing 1A and the flange 113 of the fan 112. The force member 101 applies force to the first bearing 1A downward relative to the rotating body 110.

[0038] The second bearing 1B is inserted into the cylinder 121 from the opposite side of the rotating body 110. The upper end surface of the outer ring 20 of the second bearing 1B contacts the step surface 123 of the inner circumferential surface of the cylinder 121. The outer ring 20 of the second bearing 1B is restricted in displacement on the rotating body 110 side by the step surface 123 of the inner circumferential surface of the cylinder 121. The lower end surface of the inner ring 10 of the second bearing 1B contacts the C-shaped ring 103 mounted on the shaft 111. The displacement of the inner ring 10 of the second bearing 1B in the direction away from the rotating body 110 relative to the shaft 111 is restricted by the C-shaped ring 103.

[0039] [First embodiment] Figure 2 It is a top view of the rolling bearing according to the first embodiment. Figure 3 is a longitudinal sectional view of a rolling bearing according to the first embodiment, showing Figure 2 In addition, Figure 2 In FIG. 1 , a part of a resin cover 60 to be described later is cut away and shown. like Figure 2 and Figure 3 As shown, each bearing 1 includes an inner ring 10 and an outer ring 20 as raceways, a plurality of rolling elements 30, a retainer 40, and a pair of sealing members 50. The inner ring 10 and the outer ring 20 have a central axis O as a common axis.

[0040] The inner ring 10 is provided as a rotating ring. The inner ring 10 is externally inserted into the shaft portion 111. The outer ring 20 is provided as a fixed ring. The outer ring 20 surrounds the inner ring 10 from the outside in the radial direction with an annular space provided between the inner ring 10 and the outer ring 20. A plurality of rolling elements 30 are arranged between the inner ring 10 and the outer ring 20 and are held by the retainer 40 in a rollable manner. The retainer 40 holds each rolling element 30 in a rotatable manner in a state where the plurality of rolling elements 30 are evenly arranged in the circumferential direction. The sealing member 50 covers the annular space between the inner ring 10 and the outer ring 20 from the outside in the axial direction.

[0041] The outer ring 20 includes an outer ring body 21 (raceway ring body) and a resin cover 60 (resin portion) mounted on the outer ring body 21. The outer ring body 21 is formed in an annular shape from a metal material such as stainless steel or bearing steel. The width of the outer ring body 21 along the axial direction is equal to the width of the inner ring 10 along the axial direction. The outer ring body 21 includes an inner peripheral surface 22 and an outer peripheral surface 25. The inner peripheral surface 22 faces the inner ring 10 side. The outer peripheral surface 25 faces the opposite side of the inner ring 10.

[0042] The outer ring raceway surface 23 on which the rolling element 30 rolls and the fitting groove 24 for holding the sealing member 50 are formed on the inner circumferential surface 22 of the outer ring body 21. The outer ring raceway surface 23 is recessed toward the outer side in the radial direction. The outer ring raceway surface 23 is formed in a hemispherical shape in a cross-sectional view along the outer surface of the rolling element 30, and is formed in an annular shape extending in the circumferential direction over the entire circumference of the inner circumferential surface 22 of the outer ring body 21. The outer ring raceway surface 23 is formed in a portion located in the center in the axial direction of the inner circumferential surface 22 of the outer ring body 21. A pair of fitting grooves 24 are formed at the axial end portions of the inner circumferential surface 22. The fitting grooves 24 are recessed toward the inner side in the radial direction. The fitting grooves 24 are open across the inner circumferential surface 22 of the outer ring body 21 and the end surface in the axial direction. The fitting grooves 24 are formed in an annular shape extending in the circumferential direction over the entire circumference of the inner circumferential surface 22 of the outer ring body 21. A portion of the inner peripheral surface 22 of the outer ring body 21 between the outer ring raceway surface 23 and the fitting groove 24 extends in the axial direction with a constant inner diameter.

[0043] Figure 4 It is a top view of the outer ring of the first embodiment. like Figure 3 and Figure 4 As shown, the resin cover 60 is assembled to the outer ring body 21 in a manner that cannot be relatively displaced. The resin cover 60 is formed of an insulating resin material. As the type of resin forming the resin cover 60, it is preferably formed of one or more of polybutylene terephthalate (PBT), polyphenylene sulfide (PPS) and polyetheretherketone (PEEK), which have low moisture absorption, are easy to form with high molding accuracy, and are also excellent in chemical resistance. In addition, potassium titanate whiskers can be added to the resin as a reinforcing material. Potassium titanate whiskers are preferably blended in an amount of 5% to 40%, and more preferably blended in an amount of 10 to 30%. In addition, it is ideal that glass fiber or carbon fiber is not added to the resin as a reinforcing material. This is because if hard glass fiber or carbon fiber is added to the resin, it is difficult to process the resin cover after insert molding by mechanical processing such as centerless machining, and it is easy to damage the grindstone or tool. On the other hand, potassium titanate whiskers are softer than glass fiber or carbon fiber, and are small in thickness and length, and are easy to machine. Resin to which potassium titanate whiskers are added is easier to machine than resin alone.

[0044] The resin cover 60 is formed in a cylindrical shape. The outer peripheral surface of the resin cover 60 is the outer peripheral surface of the outer ring 20, and the bearing 1 is inserted into the cylindrical portion 121 and is in sliding contact with the inner peripheral surface of the cylindrical portion 121. The resin cover 60 is arranged over the entire length of the outer ring 20 in the axial direction. The resin cover 60 includes: a peripheral wall portion 61 that covers the outer peripheral surface 25 of the outer ring body 21; and a pair of flange portions 62 that are connected to the peripheral wall portion 61 and cover the end surface of the outer ring body 21 in the axial direction. The peripheral wall portion 61 covers the entire outer peripheral surface 25 of the outer ring body 21 from the outer side in the radial direction. The peripheral wall portion 61 extends in the axial direction with a constant outer diameter. The flange portion 62 extends from the axial end of the peripheral wall portion 61 to the inner side in the radial direction. The flange portion 62 extends over the entire circumference around the central axis O. The resin cover 60 is integrally insert-molded with the outer ring body 21.

[0045] The outer ring 20 also includes a fitting portion 27 that fits into the base 120 of the rotating device in a non-rotatable manner. The fitting portion 27 is formed on the end surface of the outer ring 20 that faces outward in the axial direction. The fitting portion 27 is provided on the resin cover 60. The fitting portion 27 is a convex portion that protrudes outward in the axial direction from the flange portion 62. The fitting portion 27 only protrudes to one side in the axial direction. That is, the fitting portion 27 is only combined with one flange portion 62 of the pair of flange portions 62. A plurality of fitting portions 27 (in the example shown in the figure, 4) are provided at equal intervals in the circumferential direction. The fitting portion 27 is formed in a cylindrical shape. However, the shape of the fitting portion 27 is not particularly limited as long as it can be inserted into the fitted portion 125 described later. All the fitting portions 27 are formed in the same shape as each other. All the fitting portions 27 have rotational symmetry with respect to the axis O as the center. The fitting portion 27 has a gap in the radial direction relative to the outer peripheral edge and the inner peripheral edge of the flange portion 62 when viewed in the axial direction. However, the fitting portion may be connected to at least one of the outer peripheral edge and the inner peripheral edge of the flange portion 62 when viewed in the axial direction. In addition, the fitting portion 27 overlaps with the outer peripheral surface 25 of the outer ring body 21 when viewed in the axial direction, but the entire fitting portion may overlap with the outer ring body 21 when viewed in the axial direction, or the entire fitting portion may not overlap with the outer ring body 21 when viewed in the axial direction.

[0046] The inner ring 10 is formed in an annular shape from a metal material such as stainless steel or bearing steel. An inner ring raceway surface 11 that is recessed inward in the radial direction is formed on the outer circumferential surface of the inner ring 10. The inner ring raceway surface 11 is formed in a hemispherical shape in a cross-sectional view along the outer surface of the rolling element 30, and is formed in an annular shape that extends in the circumferential direction over the entire circumference of the outer circumferential surface. The inner ring raceway surface 11 is formed in a portion of the outer circumferential surface of the inner ring 10 that is located in the center in the axial direction, and is arranged to face the outer ring raceway surface 23 in the radial direction. The portion of the outer circumferential surface of the inner ring 10 other than the inner ring raceway surface 11 extends in the axial direction with a constant outer diameter.

[0047] The plurality of rolling elements 30 are formed in a spherical shape from a metal material such as stainless steel or bearing steel. The plurality of rolling elements 30 are disposed between the outer ring raceway surface 23 and the inner ring raceway surface 11 and are supported in a rollable manner by the outer ring raceway surface 23 and the inner ring raceway surface 11. The plurality of rolling elements 30 are maintained at intervals in the circumferential direction by a retainer 40.

[0048] like Figure 3 As shown, the retainer 40 is formed of a synthetic resin or a metal material as a whole in an annular shape. The retainer 40 is arranged coaxially with the central axis O. The retainer 40 includes: an annular portion 41, which is formed in an annular shape and is arranged below the plurality of rolling elements 30; and a plurality of columnar portions 42, which are protruded upward from the annular portion 41 and are arranged at intervals in the circumferential direction. The columnar portions 42 are arranged evenly in the circumferential direction. A pair of columnar portions 42 adjacent to each other in the circumferential direction form a ball hole between each other. The ball hole penetrates the retainer 40 in the radial direction and opens upward at the upper end surface of the retainer 40. The ball hole is arranged corresponding to the number of rolling elements 30, and the rolling elements 30 are respectively held in a rolling manner. Thus, the retainer 40 arranges the rolling elements 30 evenly in the circumferential direction at intervals.

[0049] like Figure 2 and Figure 3 As shown, the sealing component 50 is formed in the shape of a circular plate. The sealing component 50 is arranged coaxially with the central axis O. The sealing component 50 is assembled to the outer ring 20. One sealing component 50 is arranged on each side in the axial direction relative to the plurality of rolling elements 30. The sealing component 50 includes: a sealing fitting portion 51, which is fitted into the fitting groove 24 of the outer ring body 21; and a cover portion 53, which extends from the sealing fitting portion 51 to the inner side in the radial direction. The sealing component 50 extends in the radial direction in a manner that at least spans the center of the rolling element 30 when viewed from above. The inner peripheral edge of the cover portion 53 is arranged with a gap between it and the outer peripheral surface of the inner ring 10. The sealing fitting portion 51 is locked to the wall surface of the fitting groove 24, so that the sealing component 50 is fixed to the outer ring body 21.

[0050] Figure 5 is a cross-sectional view of the fan motor of the first embodiment, which is equivalent to Figure 1 A portion of the V portion is shown enlarged. like Figure 5As shown, the bearing 1 is arranged on the fan motor 100 in such a manner that the fitting portion 27 contacts the base 120. The base 120 is formed with a fitting portion 125 that fits into the fitting portion 27 of the bearing 1. The fitting portion 125 is a recessed portion of a step surface 122 formed on the inner peripheral surface of the cylinder 121 of the base 120. The fitting portion 125 is pre-formed on the step surface 122 before the bearing 1 is assembled on the cylinder 121. The fitting portion 27 is inserted into the fitting portion 125 one-to-one. By inserting the fitting portion 27 into the fitting portion 125, the end surface of the outer ring 20 (the flange portion 62 of the resin cover 60) is in surface contact with the periphery of the fitting portion 125 of the step surface 122. The step surface 122 may be provided with the same number of engaged portions 125 as the engaging portion 27, or may be provided with a greater number of engaged portions 125 than the engaging portions 27 (for example, an integral multiple of the engaging portions 27). Ideally, each engaged portion 125 is formed in a manner that substantially no gap is generated in the circumferential direction and the radial direction relative to the engaging portion 27 inserted into the engaged portion 125. The engaged portion 125 has no gap in the circumferential direction relative to the engaging portion 27, so that the engaging portion 27 is engaged with the barrel 121 in a manner that is non-rotatable relative to each other. However, the engaged portion 125 may have a slight gap in the circumferential direction relative to the engaging portion 27, and even with this configuration, the engaging portion 27 is engaged with the barrel 121 in a manner that is non-rotatable relative to each other beyond a predetermined angle. In addition, in Figure 5 , the relationship between the first bearing 1A and the stepped surface 122 is shown, but the relationship between the second bearing 1B and the stepped surface 123 is the same.

[0051] As described above, the bearing 1 of the present embodiment is configured such that the outer ring 20 is mounted on the base 120 of the fan motor 100, and the outer ring 20 is provided with a resin cover 60, and the resin cover 60 has a fitting portion 27 that is fitted to the base 120 in a manner that is non-rotatable relative to the outer ring 20. According to this configuration, the outer ring 20 can be restricted from rotating relative to the base 120. Furthermore, the fitting portion 27 is provided on the resin cover 60 of the outer ring 20, so that the processability of the outer ring 20 is improved compared to the case where the fitting portion is provided on the metal member of the outer ring, and the reduction in the roundness of the outer ring 20 due to the formation of a complex shape can be suppressed. Therefore, the reduction in the accuracy of the bearing 1 can be suppressed, and the occurrence of slippage of the outer ring 20 can be suppressed at the same time.

[0052] If a fitting portion is provided on the outer peripheral surface as the mounting surface of the outer ring, the workability of the outer peripheral surface during molding may be reduced and the dimensional accuracy of the outer peripheral surface may be deteriorated. According to the present embodiment, the fitting portion 27 is provided on the end surface of the outer ring 20 facing the outer side in the axial direction, thereby suppressing the deterioration of the dimensional accuracy of the outer peripheral surface as the mounting surface of the outer ring 20. Therefore, the reduction in the accuracy of the bearing 1 can be suppressed.

[0053] A plurality of fitting portions 27 are provided at equal intervals in the circumferential direction. This configuration allows the shape of the resin cover 60 to have rotational symmetry, and can suppress deformation of the resin cover 60 after molding. In addition, the force applied from the cylinder 121 to the outer ring 20 can be evenly dispersed, and deformation of the outer ring 20 can be suppressed.

[0054] The outer ring 20 includes a metal outer ring body 21 on which an outer ring raceway surface 23 is formed. The resin cover 60 covers the outer ring body 21. According to this configuration, the contact portion of the outer ring 20 with the rolling element 30 is formed of a metal material, and thus, by providing the resin cover 60, it is possible to suppress a decrease in the durability of the bearing 1. In addition, the resin cover 60 can be integrally insert-molded with the outer ring body 21, and thus it is possible to suppress positional deviation of the resin cover 60 relative to the outer ring body 21 and to mold the outer ring 20 with good precision. Furthermore, the outer ring body 21 is covered by the resin cover 60, and thus electrical corrosion can be prevented.

[0055] The resin cover 60 includes potassium titanate whiskers. According to this configuration, the resin cover 60 can be a member having excellent wear resistance and surface smoothness. In addition, compared with the case where the resin cover includes glass fiber or carbon fiber as a reinforcing material, the processability when the resin cover 60 is formed by cutting or grinding can be improved.

[0056] The resin material forming the resin cover 60 is formed of one or more of polybutylene terephthalate, polyphenylene sulfide, and polyetheretherketone. According to this structure, it is possible to suppress moisture absorption of the resin cover 60 and dimensional changes of the outer ring 20 due to moisture absorption. Therefore, an outer ring 20 suitable for use in water can be obtained.

[0057] The fitting portion 27 is provided only on one of the pair of end faces of the outer ring 20. With this configuration, even if the internal structure of the bearing 1, such as the shape of the retainer 40 or the arrangement of the grease, is asymmetric in the axial direction, the orientation of the internal structure of the bearing 1 and the arrangement of the fitting portion 27 can be determined in advance, and thus the orientation of the internal structure of the bearing 1 can be grasped from the appearance of the bearing 1.

[0058] The fan motor 100 includes a bearing 1, a base 120 having an engaged portion 125 engaged with an engaging portion 27, and a rotating body 110 supported by the base 120 via the bearing 1 and arranged to be rotatable relative to the base 120. According to this configuration, the fan motor 100 can be configured to suppress the slip of the outer ring 20 of the bearing 1.

[0059] [Second embodiment] The second embodiment will be described. The second embodiment is different from the first embodiment in that the entire outer ring is made of resin. The configuration other than the configuration described below is the same as that of the first embodiment.

[0060] Figure 6 is a longitudinal sectional view of a rolling bearing according to the second embodiment, which is equivalent to Figure 3 . Figure 7 It is a top view of the outer ring of the second embodiment. like Figure 6 and Figure 7 As shown, the bearing 201 includes an inner ring 210, an outer ring 220, a plurality of rolling elements 230, and a cage 240. The bearing 201 does not include the seal member 50 of the first embodiment.

[0061] The entire outer ring 220 is formed of a resin material. The outer ring 220 is formed of one or more of polybutylene terephthalate (PBT), polyphenylene sulfide (PPS), and polyetheretherketone (PEEK). Potassium titanate whiskers are added as a reinforcing material to the resin forming the outer ring 220. The potassium titanate whiskers are preferably blended in an amount of 10% to 40%.

[0062] The outer ring 220 has an inner circumferential surface 222 and an outer circumferential surface 225. The inner circumferential surface 222 faces the inner ring 210 side. The outer circumferential surface 225 faces the opposite side of the inner ring 210. The inner circumferential surface 222 is formed with an outer ring raceway surface 223 on which the rolling element 230 rolls. The portion of the inner circumferential surface 222 of the outer ring 220 other than the outer ring raceway surface 223 extends in the axial direction with a constant outer diameter.

[0063] The outer ring 220 also has a fitting portion 227 that is fitted into the base 120 of the fan motor 100 in a manner that is non-rotatable relative to each other. That is, in the present embodiment, the outer ring 220 is a resin portion having the fitting portion 227. The fitting portion 227 is formed on the end face of the outer ring 220 that faces outward in the axial direction. The fitting portion 227 is a recess formed on the end face of the outer ring 220. The fitting portion 227 is provided only on one end face of the outer ring 220. A plurality of fitting portions 227 are provided at equal intervals in the circumferential direction (4 in the illustrated example). The fitting portion 227 extends in the radial direction. The fitting portion 227 opens across the end face of the outer ring 220 and each of the inner peripheral surface 222 and the outer peripheral surface 225 of the outer ring 220. However, the shape of the fitting portion 227 is not particularly limited. For example, the fitting portion 227 may not have an opening in at least one of the inner circumferential surface 222 and the outer circumferential surface 225 of the outer ring 220. All the fitting portions 227 are formed in the same shape. All the fitting portions 227 have rotational symmetry with respect to the axis O. A gate 228 is formed on the bottom surface of the fitting portion 227. The gate 228 is formed in one fitting portion 227. However, the gate 228 may also be formed in a plurality of fitting portions 227. In addition, the gate 228 itself may not be formed.

[0064] The inner ring 210 is formed of a resin material. The inner ring 210 is formed of one or more of polybutylene terephthalate (PBT), polyphenylene sulfide (PPS), and polyetheretherketone (PEEK). In addition, reference numeral 211 in the figure indicates an inner ring raceway surface.

[0065] The rolling element 230 is formed of a non-metal material such as ceramic, glass, or a resin material. The holder 240 is formed of a resin material, for example, one or more of polybutylene terephthalate (PBT), polyphenylene sulfide (PPS), and polyetheretherketone (PEEK).

[0066] The bearing 201 is arranged on the fan motor 100 in the same manner as in the first embodiment, such that the fitting portion 227 contacts the base 120. In this embodiment, the base 120 has stepped surfaces 122 and 123 (see FIG. 1 ) on the inner circumferential surface of the cylinder 121 as a fitting portion of the fitting portion 227 that fits into the bearing 201. Figure 1 ) is formed with a convex portion. The engaged portion is pre-formed on the step surfaces 122, 123 before the bearing 201 is assembled on the cylinder 121. The engaged portion is inserted into the engaging portion 227 one-to-one. By inserting the engaged portion into the engaging portion 227, the end face of the outer ring 220 makes surface contact with the surrounding of the engaged portion of the step surfaces 122, 123. On each step surface 122, 123, there are engaged portions equal to or less than the number of engaging portions 227. Ideally, each engaged portion is formed in a manner that substantially no gap is generated in the circumferential direction and the radial direction relative to the engaging portion 227 into which the engaged portion is inserted.

[0067] In this embodiment, the same effects as those of the first embodiment are achieved. In addition, in this embodiment, the entire outer ring 220 is a resin portion having the fitting portion 227. According to this configuration, compared with a case where a portion of the outer ring is made of metal, the outer ring 220 can be easily molded, and the productivity of the outer ring 220 can be improved. Furthermore, it is possible to suppress the flow of current inside the bearing 201 and the occurrence of electrical corrosion in the bearing 201.

[0068] Furthermore, since potassium titanate whiskers are added to the resin forming the outer ring raceway surface 223 , excellent wear resistance and surface smoothness are imparted to the outer ring raceway surface 223 , and a highly durable resin bearing 201 can be obtained.

[0069] Inner ring 210, outer ring 220, and retainer 240 are formed of the above-mentioned resin material with low moisture absorption, and rolling element 230 is formed of a non-metallic material. With this structure, the dimensional change of each component of bearing 201 due to moisture absorption is suppressed, and bearing 201 can be used in water.

[0070] A gate 228 is formed inside the fitting portion 227. According to this configuration, it is possible to suppress the gate 228 from protruding in the axial direction from the outer ring 220. Therefore, the bearing 201 can be assembled to the base 120 with good accuracy.

[0071] In the second embodiment, the inner ring 210 and the outer ring 220 are formed of a resin material. However, as long as at least the raceway ring provided with the fitting portion (the outer ring in the second embodiment) of the inner ring and the outer ring is formed of a resin material, the above-described effects are achieved. In addition, the rolling elements may not be formed of a resin material and may be formed of a metal material.

[0072] [Third Embodiment] The third embodiment will be described. The third embodiment is different from the first embodiment in that the fitting portion is formed on the outer peripheral surface of the outer ring. In addition, the configuration other than the configuration described below is the same as that of the first embodiment.

[0073] Figure 8 It is a top view of the outer ring of the third embodiment. Figure 9 It is a cross-sectional view of the fan motor of the third embodiment and is equivalent to Figure 5 the figure. As Figure 8 and Figure 9 shown, the bearing 301 includes an outer ring 320 instead of the outer ring 20 of the first embodiment. The outer ring 320 further includes a fitting portion 327 that is non-rotatably fitted to the base 120 of the rotating device. The fitting portion 327 is formed on the outer peripheral surface of the outer ring 320. The fitting portion 327 is provided on the resin cover 60. The fitting portion 327 is a convex portion that protrudes outward in the radial direction from the peripheral wall portion 61. A plurality of (four in the illustrated example) fitting portions 327 are provided at equal intervals in the circumferential direction. The fitting portion 327 has a constant width in the circumferential direction and extends in the axial direction. The fitting portion 327 extends over substantially the entire length in the axial direction of the resin cover 60. However, the shape of the fitting portion 327 is not particularly limited as long as it can be inserted into the fitting portion 126 described later. All the fitting portions 327 are formed in the same shape as each other. All the fitting portions 327 are rotationally symmetric with respect to the axis O.

[0074] The base 120 is provided with an engaged portion 126 that is engaged with an engaging portion 327 of the bearing 301. The engaged portion 126 is a recess formed on the inner circumferential surface of the cylinder 121 of the base 120. The engaged portion 126 is open at the end surface outside the axial direction of the cylinder 121 and extends in the axial direction. The engaging portion 327 is inserted into the engaged portion 126 one-to-one. The engaged portions 126 may be provided in the same number as the engaging portions 327, or may be provided in a greater number than the engaging portions 327 (for example, an integral multiple of the engaging portions 327). Ideally, each engaged portion 126 is formed in a manner that substantially no gap is generated in the circumferential direction and the radial direction relative to the engaging portion 327 inserted into the engaged portion 126. The engaged portion 126 has no gap in the circumferential direction relative to the engaging portion 327, so that the engaging portion 327 is engaged with the cylindrical portion 121 in a manner that cannot rotate relative to each other. However, the engaged portion 126 may have a slight gap in the circumferential direction relative to the engaging portion 327, and even with this configuration, the engaging portion 327 is engaged with the cylindrical portion 121 in a manner that cannot rotate relative to each other by more than a predetermined angle.

[0075] In this embodiment, the same effects as those of the first embodiment are achieved. In addition, in this embodiment, the fitting state of the fitting portion 327 and the fitted portion 126 of the cylindrical portion 121 can be visually confirmed during the process of assembling the bearing 301 to the cylindrical portion 121. Therefore, the bearing 301 having excellent operability when assembled to the cylindrical portion 121 can be obtained.

[0076] In addition, since a plurality of fitting portions 327 are provided at equal intervals in the circumferential direction, the shape of the resin cover 60 can be rotationally symmetrical, and deformation of the resin cover 60 after molding can be suppressed. In addition, the force applied from the cylinder 121 to the outer ring 320 can be evenly dispersed, and deformation of the outer ring 320 can be suppressed.

[0077] [Fourth embodiment] The fourth embodiment will be described. In the third embodiment, the resin cover 60 is arranged over the entire length of the outer ring 320 in the axial direction. In contrast, the fourth embodiment is different from the third embodiment in that the resin cover 460 is arranged only on a portion of the outer ring 420 in the axial direction. In addition, the configuration other than the configuration described below is the same as that of the third embodiment.

[0078] Figure 10 is a cross-sectional view of a fan motor according to a fourth embodiment, which is equivalent to Figure 5 . like Figure 10As shown, the bearing 401 includes an outer ring 420 instead of the outer ring 320 of the third embodiment. The outer ring 420 includes an outer ring body 21 and a resin cover 460 (resin portion) mounted on the outer ring body 21. For example, the resin cover 460 is integrally insert-molded with the outer ring body 21. However, the molding method of the resin cover 460 is not limited thereto. For example, the resin cover 460 may be formed separately from the outer ring body 21 and mounted on the outer peripheral surface of the outer ring body 21 by press-fitting. The resin cover 460 is arranged only at a position on the outer ring raceway surface 23 of the outer ring 420 that is closer to the axial side than the center position in the axial direction. The center position in the axial direction of the outer ring raceway surface 23 is a portion of the outer ring raceway surface 23 where the normal direction is parallel to the radial direction. The resin cover 460 includes: a peripheral wall portion 461 that covers the outer peripheral surface 25 of the outer ring body 21; and a flange portion 62 that is connected to the peripheral wall portion 461 and covers one end surface of the outer ring body 21 in the axial direction. The peripheral wall portion 461 extends in the axial direction with a constant outer diameter. The other end of the peripheral wall portion 461 in the axial direction is located at a position closer to the outer ring raceway surface 23 in the axial direction than the center position in the axial direction. The peripheral wall portion 461 covers the outer peripheral surface of the outer ring body 21 over the entire circumference. The flange portion 62 is combined at one end of the peripheral wall portion 461 in the axial direction. The peripheral wall portion 461 is provided with a fitting portion 327.

[0079] The bearing 401 is installed in the fan motor 100 as the first bearing 401A in such a manner that the resin cover 460 is located on the side opposite to the direction of the force of the force member 101 acting on the inner ring 10. Thus, the resin cover 460 is arranged only at a position of the outer ring raceway surface 23 that is closer to the force member 101 in the axial direction than the center position in the axial direction. In other words, the resin cover 460 has a contact portion with respect to the cylinder 121 only at a position of the outer ring raceway surface 23 that is closer to the force member 101 in the axial direction than the center position in the axial direction. In addition, the end of the outer ring body 21 abuts against the step surface 122 of the cylinder 121, thereby limiting the displacement of the first bearing 401A relative to the inner side of the cylinder 121 in the axial direction.

[0080] In this embodiment, the same effects as those of the third embodiment are achieved. In addition, in this embodiment, the following effects are achieved. The rolling element 30 is subjected to the force of the force applying member 101 and is aligned with the outer ring raceway surface 23 on the side closer to the axial direction than the axial center position thereof (at Figure 10Here, if the resin cover is sandwiched between the contact point of the outer ring raceway surface 23 with the rolling element 30 and the cylinder 121 in the radial direction, when the resin cover is strained and the strain is transmitted to the outer ring body 21, there is a possibility that the contact point of the outer ring raceway surface 23 with the rolling element 30 changes and the first bearing 401A may malfunction. According to the present embodiment, the resin cover 460 does not contact the cylinder 121 at a position on the axial side of the outer ring raceway surface 23 relative to the axial center position, so even if strain is generated in the resin cover 460 near the contact point of the outer ring 420 with the rolling element 30, the strain can be prevented from affecting the outer ring body 21. Therefore, it is possible to suppress the change of the contact point of the outer ring raceway surface 23 with the rolling element 30 and the malfunction of the first bearing 401A.

[0081] In addition, in the present embodiment, the position of the contact portion between the resin cover 460 and the cylinder 121 is limited by arranging the resin cover 460 only in a portion in the axial direction of the outer ring 410, but the present invention is not limited to this configuration. For example, the outer peripheral surface may be reduced in diameter to avoid contact with the cylinder in a portion in the axial direction of the resin cover, thereby limiting the position of the contact portion between the resin cover and the cylinder.

[0082] In addition, the present invention is not limited to the above-mentioned embodiment described with reference to the drawings, and various modifications are conceivable within the technical scope of the present invention. For example, in the above embodiment, a fan motor is exemplified as a rotating device, but the rotating device is not limited to this. For example, as a rotating device, the present invention can also be applied to a dental handpiece or a spindle motor of a hard disk drive. In addition, in the above embodiment, the inner ring is set as a rotating ring and the outer ring is set as a fixed ring. However, the inner ring can also be set as a fixed ring and the outer ring can be set as a rotating ring.

[0083] Furthermore, in the above-described embodiment, the fitting portion is provided on the outer ring, but the fitting portion may be provided on the inner ring, and the fitted portion may be provided on the rotating body.

[0084] In the above-mentioned embodiment, the fitting portion 27, 227 is provided only at one end of the outer ring 20, 220 in the axial direction, but the present invention is not limited to this configuration. That is, the fitting portion may be provided at both ends of the outer ring in the axial direction.

[0085] In addition, the components in the above-mentioned embodiments can be appropriately replaced with well-known components without departing from the scope of the present invention, and the above-mentioned embodiments can be appropriately combined. For example, the resin outer ring of the second embodiment can be provided with a convex fitting portion in place of the concave fitting portion in the first embodiment. In addition, the resin cover of the outer ring of the first embodiment can be provided with a concave fitting portion in place of the convex fitting portion in the second embodiment. In this case, the fitting portion is formed by penetrating the flange portion of the resin cover in the axial direction, and the fitting portion can be used as a portion where the ejector sleeve of the metal mold used when insert molding the resin cover contacts the end surface of the outer ring body. In addition, the resin cover of the outer ring of the third embodiment or the fourth embodiment can be provided with a concave fitting portion in place of the convex fitting portion. In addition, the first embodiment or the second embodiment can be combined with the third embodiment to provide the fitting portion on both the end surface and the outer peripheral surface of the resin portion. Description of Reference Numerals

[0086] 1, 201, 301, 401...bearing 10, 210...inner ring 20, 220, 320, 420...outer ring (a raceway ring) 21...outer ring body (raceway ring body) 23...outer ring raceway surface (raceway surface) 27, 227, 327...fitting portion 30, 230...rolling element 60, 460...resin cover (resin portion) 101...force applying member 110...rotating body 120...base (assembled member) 125...fitted portion

Claims

1. A rolling bearing comprising: an inner ring and an outer ring, which are coaxially arranged with each other; and A rolling element is arranged between the inner ring and the outer ring, The rolling bearing is a rolling bearing in which one of the inner ring and the outer ring is assembled to an assembled component. The one raceway ring includes a resin portion having a fitting portion that is fitted to the mounted member in a relatively non-rotatable manner.

2. The rolling bearing according to claim 1, wherein: The one raceway ring has an end surface facing outward in the axial direction, The fitting portion is provided on the end surface.

3. The rolling bearing according to claim 1, wherein: The one raceway ring has a circumferential surface facing the mounted component side in the radial direction, The fitting portion is provided on the peripheral surface.

4. The rolling bearing according to claim 1, wherein: The one raceway ring includes a metal raceway ring body having a raceway surface on which the rolling element rolls. The resin portion is a resin cover that covers the raceway ring body.

5. The rolling bearing according to claim 4, wherein: The resin cover is arranged only at a position on one side in the axial direction relative to a center position in the axial direction of the raceway surface of the one raceway ring.

6. The rolling bearing according to claim 1, wherein: The entirety of the one raceway ring is the resin portion.

7. The rolling bearing according to claim 6, wherein: The other raceway of the inner race and the outer race is made of resin.

8. The rolling bearing according to claim 1, wherein: The resin portion includes potassium titanate whiskers.

9. The rolling bearing according to claim 8, wherein: The resin material forming the resin portion is formed of one or more of polybutylene terephthalate, polyphenylene sulfide, and polyetheretherketone.

10. A rotating device comprising: The rolling bearing according to any one of claims 1 to 9; The assembled component has an engaged portion engaged with the engaging portion; and The rotating body is supported by the mounted component via the rolling bearing and is arranged to be rotatable relative to the mounted component.

11. A rotating device comprising: The rolling bearing according to claim 4 or claim 5; The assembled component has an engaged portion engaged with the engaging portion; a rotating body supported by the mounted component via the rolling bearing and arranged to be rotatable relative to the mounted component; and a force applying member, which applies force to one side of the other raceway ring of the inner ring and the outer ring in the axial direction, The resin cover has a contact portion with respect to the mounted component only at a position of the raceway surface that is closer to the other side in the axial direction than the center position in the axial direction.

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