JP2001355639A - Bearing device - Google Patents

Abstract

(57) [Problem] To provide a bearing device capable of improving the formability of an insulating material such as a resin film for preventing electrolytic corrosion and improving the film strength. A stepped portion (21b) including a flange surface (21d) extending in a radial direction is formed at an intersection of an outer peripheral surface (21h) and a side surface (21a) of a side surface (21a) of an outer race (21).
Is coated on the flange surface 21d of the stepped portion 21d. Therefore, even when the bearing retainer 15 is pressed against the side surface 21a of the outer race 21 during assembly, for example, the gap between the bearing retainer 15 and the flange surface 21d is formed. The radially outward force is not applied to the insulator R sandwiched between them, thereby making it possible to suppress breakage or peeling of the insulator R.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

TECHNICAL FIELD The present invention relates to a bearing device,
In particular, the present invention relates to a bearing device that can be used for electric motors for railway vehicles and that can prevent electrolytic corrosion.

[0002]

2. Description of the Related Art Conventionally, in a bearing device capable of preventing electrolytic corrosion used in electric motors for railway vehicles, etc., a leakage current from a housing or a shaft flows between a rolling element of a bearing and a bearing ring to cause electrolytic corrosion. In order to prevent the occurrence of the phenomenon, an electrically insulating coating (insulating coating) is provided on at least one surface of a housing or a shaft to which an outer ring or an inner ring is fitted, and an external current is interrupted. I have.

As an insulating film of a conventional bearing device capable of preventing electrolytic corrosion, Japanese Patent Application Laid-Open No. 3-277818 discloses, for example, an insulating film formed of a polyphenylene sulfide resin containing glass fibers (hereinafter referred to as a PPS resin). I have.

Japanese Patent Application Laid-Open No. 5-240255 discloses an insulating film formed of a PPS resin containing glass fibers and a non-fibrous insulating inorganic filler such as calcium carbonate. I have.

[0005] In the former, a PPS resin is reinforced with glass fibers to form an insulating film having excellent creep resistance so as to obtain stable electrolytic corrosion prevention performance.
In the latter case, not only glass fiber but also non-fibrous inorganic filler is used in combination to strengthen the PPS resin. The purpose is to obtain a good formability.

Incidentally, the reason why the insulating coating of the anti-corrosion rolling bearing is required to have high creep resistance is that the insulating coating is formed on at least one of the inner and outer races of the bearing, which is assembled between the rotary shaft and the housing with an interference. So
If the creep resistance is low, the thickness of the insulating film decreases with the passage of time, and the interference of the bearing cannot be kept constant.

In recent years, there has been an increasing demand for speeding-up of railway vehicles, and PPS resins containing a heat conduction improving filler in PPS resin in order to suppress bearing heat generation (Japanese Patent Laid-Open No. 7-31).
No. 0748, Japanese Unexamined Patent Application Publication No. 10-306828), and the like, the performance of insulating coatings has been improved.

[0008]

However, in a bearing device capable of preventing electrolytic corrosion, there is a problem that a resin film is damaged due to assembly of the bearing device. This will be described below. FIG. 6 is a view showing the vicinity of an end portion of an outer ring of a conventional bearing device capable of preventing electrolytic corrosion. The outer surface of the outer ring 11 has a resin material R
Is coated.

In order to prevent electrolytic corrosion, a strict tolerance is set for the thickness of the coating material R, and the tolerance is strictly controlled.
In the vicinity, when the resin material R is coated, the flow becomes poor, and the resin film thickness α may be reduced.

In order to solve such a problem, it is conceivable to increase the curvature of the chamfered portion 11a of the outer race 11, improve the resin moldability of the resin material R coated on the outer surface thereof, and increase the thickness of the resin film. Can be FIG. 7 shows an outer ring 1 having an increased curvature.
FIG. 7 is a cross-sectional view similar to FIG. 6, showing a state in which a resin material R is coated on one chamfered portion 11a.

With the configuration shown in FIG. 7, the resin moldability of the resin material R coated on the outer surface of the chamfered portion 11a can be increased to increase the thickness of the resin film. A new problem arises because the curvature is increased. Specifically, when the bearing device is assembled, the outer ring 1
The bearing member 15 abuts on the side surface of the outer ring 11. The thrust force F generated at this time causes the resin material R sandwiched between the bearing holder 15 and the chamfered portion 11a of the outer ring 11 to have a radially outward component force. Is generated and pushed by the component force. As a result, depending on the tightening force (bolt tightening force) on the bearing retainer 15, the resin material R may be chipped or peeled off, thereby deteriorating the insulation performance. It may cause damage to the bearing.

Accordingly, the present invention has been made in view of the above-mentioned problems of the prior art, and provides a bearing device capable of improving the formability of an insulating material such as a resin film for preventing electrolytic corrosion and improving the film strength. With the goal.

[0013]

According to the present invention, there is provided a bearing device comprising: an outer ring; an inner ring; and a plurality of rolling elements rotatably disposed between the outer ring and the inner ring. A step is formed at an intersection between the outer peripheral surface of the outer ring and at least one side surface, and an insulator is coated on the step.

A bearing device according to the present invention is a bearing device comprising an outer ring, an inner ring, and a plurality of rolling elements rotatably arranged between the outer ring and the inner ring, wherein an inner peripheral surface of the inner ring is provided. A step is formed at the intersection with at least one of the side surfaces, and an insulator is coated on the step.

[0015]

According to the bearing device of the present invention, the outer ring, the inner ring,
A plurality of rolling elements rotatably disposed between the outer ring and the inner ring; a bearing device comprising: a step portion formed at an intersection between an outer peripheral surface of the outer ring and at least one side surface; Since the insulator is covered with the stepped portion, the stepped portion is provided at the intersection between the outer peripheral surface of the outer ring and at least one side surface, so that the formability of the insulator at the intersection is formed. To increase the film thickness.
Further, even when the bearing retainer is pressed against the side surface of the outer ring, for example, during assembly, the insulator sandwiched between the bearing retainer and the flat surface of the step portion has a radially outer portion. No direction force is given,
Thereby, breakage or peeling of the insulator can be suppressed.

According to the bearing device of the present invention, in the bearing device including the outer ring, the inner ring, and a plurality of rolling elements rotatably arranged between the outer ring and the inner ring, A step is formed at the intersection between the peripheral surface and at least one side surface, and the insulator is covered by the step portion, so that the intersection between the inner peripheral surface of the inner ring and at least one side surface is formed. By providing the step in the portion, the formability of the insulator at the intersection can be enhanced and the film thickness can be secured. Further, even when the bearing retainer is pressed against the side surface of the inner ring, for example, at the time of assembly, the insulator sandwiched between the bearing retainer and the flat surface of the step portion has a radial direction. No directional force is applied, which can suppress breakage or peeling of the insulator.

[0017]

Embodiments of the present invention will be described below in detail with reference to the drawings. FIG. 1 is a partial cross-sectional view of the bearing device according to the first embodiment. FIG.
FIG. 3 is an enlarged view of a part II of the configuration of FIG. 1, and FIG. 3 is an enlarged view of a part III of the configuration of FIG. 1. Note that FIG.
In FIG. 3, the rollers 23 are omitted.

In FIG. 1, a bearing device 20 includes an outer race 21
And an inner ring 22, and a plurality of rollers 23 as rolling elements disposed between the two wheels 21 and 22. An insulator R formed of a resin material is coated on the side surface and the outer peripheral surface of the outer ring 21 and the side surface and the inner peripheral surface of the inner ring 22. As such a resin material, those disclosed in the above-mentioned publications can be used, but are not limited thereto.

In FIG. 2, a step 21b is formed at the outer edge of the side surface 21a of the outer race 21. The step portion 21b
A peripheral surface 21c coaxial with an outer peripheral surface 21h of the outer race 21;
1a, a flange surface 21d as a plane extending in parallel (that is, in a radial direction), a peripheral surface 21c, and a flange surface 21.
and a relief part 21e (including a stress relaxation function) at the time of machining provided at the intersection with the part d. A small chamfered portion 21f is formed on the outer edge of the flange surface 21d.

An insulator R is coated over the side surface 21a, the step portion 21b, and the outer peripheral surface 21h of the outer ring 21. still,
The coating of the insulator R can be performed by disposing a mold separated from the outer ring 21, injecting a resin material in which pellets are melted into a space therebetween, and removing the mold after cooling for a predetermined time. Not limited.

In FIG. 3, a step 22b is formed at the inner edge of the side surface 22a of the inner race 22. The step 22b is
A peripheral surface 22c coaxial with the inner peripheral surface 22h of the inner ring 22;
2a, a flange surface 22d as a plane extending in parallel (ie, in a radial direction), a peripheral surface 22c, and a flange surface 22.
and a relief portion 22e (including a stress relaxation function) at the time of machining provided at the intersection with d. A small chamfered portion 22f is formed on the inner edge of the flange surface 22d. The insulator R is provided on the side surface 22a of the inner race 22 and the step portion 22b.
And the inner peripheral surface 22h.

According to the present embodiment, by providing the step portion 21b at the intersection between the outer peripheral surface 21h and the side surface 21a of the outer ring 21, the formability of the insulator R at the intersection is increased, and the film thickness is reduced. Can be secured. Further, even when a force is applied in the axial direction from the bearing retainer 15 when the bearing device 20 is assembled, the flange surface 21 of the step portion 21b of the outer race 21 may be used.
Since d extends in the radial direction, the insulator R interposed between the bearing retainer 15 and the flange surface 21d does not receive a radially outward force, and the breakage or peeling is effectively prevented. Can be suppressed.

Further, as shown in FIG. 2, it is preferable that the following dimensional relationship be established in order to secure the film strength of the insulator R. c ≦ e + f (1) d ≦ g (2) Where, c: Radial length of the insulator R in contact with the bearing retainer 15 d: Axial length of the peripheral straight portion of the insulator R e: Insulator R From the inner peripheral end of the contact surface to the bearing retainer 15 to the peripheral surface 21c of the step 21b f: The radial length of the flange surface 21d of the step 21b (not including the chamfered portion 21f) g: The outer ring 21 Axial length of outer peripheral surface 21h (excluding chamfer 21f)

Further, according to the present embodiment, the stepped portion 22b is provided at the intersection between the inner peripheral surface 22h and the side surface 22a of the inner race 22, so that the formability of the insulator R at the intersection is improved, and the coating film is formed. The thickness can be secured. Also, bearing device 2
At the time of assembling 0, even if a force is applied in the axial direction from the bearing retainer 15, since the flange surface 22d of the step portion 22b of the inner race 22 extends in the radial direction, the bearing retainer 15 and the flange surface 22d The insulator R interposed between
Without receiving a radial outward force, breakage and peeling can be effectively suppressed.

FIG. 4 is an enlarged view similar to FIG. 2 showing the configuration of the bearing device of the second embodiment, and FIG. 5 is a diagram showing the configuration of the bearing device of the second embodiment. It is a similar enlarged view. The second embodiment is different from the above-described embodiment in that two steps are provided.

In FIG. 4, a first step 31b is formed on the outer edge of the side surface 31a of the outer race 31. The first stepped portion 31b has a peripheral surface 31 coaxial with the outer peripheral surface 31h of the outer race 31.
c, a flange surface 31d as a plane extending parallel to the side surface 31a (that is, in the radial direction), and a relief portion 31e at the time of machining provided at the intersection of the peripheral surface 31c and the flange surface 31d. ing.

Further, a second step 31b 'is formed outside the first step 31b. Second step 31b '
Is a peripheral surface 31c ′ coaxial with the outer peripheral surface 31h of the outer race 31,
A flange surface 31d 'as a plane extending parallel to the side surface 31a (that is, in the radial direction) and a processing (including a stress relaxation function) provided at the intersection of the peripheral surface 31c' and the flange surface 31d ' And an escape portion 31e '. A small chamfer 31f is formed at the intersection of the flange surface 31d and the peripheral surface 31c '. The insulator R is
The outer ring 31 is covered over the side surface 31a, the steps 31b, 31b 'and the outer peripheral surface 31h.

In FIG. 5, a first step portion 32b is formed on the inner edge of the side surface 32a of the inner race 32. The first step portion 32 b is formed on a peripheral surface 32 coaxial with the inner peripheral surface 32 h of the inner race 32.
c, a flange surface 32d as a plane extending parallel to the side surface 32a (that is, in the radial direction), and a relief portion 32e at the time of machining provided at the intersection of the peripheral surface 32c and the flange surface 32d. ing.

Further, a second step 32b 'is formed inside the first step 32b. Second step 32b '
Is a peripheral surface 32 c ′ coaxial with the inner peripheral surface 32 h of the inner ring 32,
A flange surface 32d 'as a plane extending parallel to the side surface 32a (that is, in a radial direction) and a processing (including a stress relaxation function) provided at an intersection between the peripheral surface 32c' and the flange surface 32d '. And an escape portion 32e '. A small chamfered portion 32f is formed at the intersection of the flange surface 32d and the peripheral surface 32c '. The insulator R is
The inner ring 32 is covered over the side surface 32a, the step portions 32b, 32b ', and the inner peripheral surface 32h.

According to the present embodiment, the stepped portions 31b and 31 are formed at the intersection of the outer peripheral surface 31h and the side surface 31a of the outer race 31.
By providing b ′, the moldability of the insulator R at such intersections is enhanced, and the film thickness can be secured. Further, even when a force is applied in the axial direction from the bearing retainer 15 at the time of assembling the device, the stepped portions 31b, 31b 'of the outer race 31 are provided.
Since the flange surfaces 31d and 31d 'of the bearing extend in the radial direction, the bearing retainer 15 and the flange surfaces 31d and 31d'
The insulator R interposed therebetween does not receive the outward force in the radial direction, and the breakage and peeling can be effectively suppressed.

Further, as shown in FIG. 4, it is preferable that the following dimensional relationship is established in order to secure the film strength of the insulator R. c ≦ h + i (3) d ≦ j + k (4) Where, c: Radial length of insulator R in contact with bearing retainer 15 d: Axial length of peripheral straight portion of insulator R h: Insulator R From the inner peripheral end of the contact surface to the bearing retainer 15 to the peripheral surface 31c of the step portion 31b i: The radial length of the flange surface 31c of the step portion 31b (not including the chamfered portion 31f) j: The outer ring 31 Axial length of outer peripheral surface 31h k: Axial length of outer peripheral surface 31d 'of step portion 31b' (excluding chamfered portion 31f)

Further, according to the present embodiment, the stepped portion 32b is formed at the intersection of the inner peripheral surface 32h and the side surface 32a of the inner race 32.
By providing 32b ', the moldability of the insulator R at the intersection is increased, and the film thickness can be secured. or,
When assembling the bearing device, even if a force is applied in the axial direction from the bearing retainer 15, the stepped portion 32b of the inner ring 32,
Since the flange surfaces 32d and 32d 'of 32b' extend in the radial direction, the bearing retainer 15 and the flange surface 32d,
The insulator R interposed between the insulator R and 32d 'does not receive a radially outward force, so that breakage and peeling can be effectively suppressed.

Although the present invention has been described with reference to the embodiments, it should be understood that the present invention should not be construed as being limited to the above embodiments, and that modifications and improvements can be made as appropriate. is there. For example, the bearing device is applicable not only to a roller bearing but also to a ball bearing.

[0034]

According to the bearing device of the present invention, a bearing device comprising an outer ring, an inner ring, and a plurality of rolling elements rotatably disposed between the outer ring and the inner ring. A step is formed at the intersection between the outer peripheral surface of the outer ring and at least one side surface, and the insulator is coated on the step portion, so that the outer peripheral surface of the outer ring intersects with at least one side surface. By providing the step in the portion, the formability of the insulator at the intersection can be enhanced and the film thickness can be secured. Further, even when the bearing retainer is pressed against the side surface of the outer ring, for example, during assembly, the insulator sandwiched between the bearing retainer and the flat surface of the step portion has a radially outer portion. No directional force is applied, which can suppress breakage or peeling of the insulator.

According to the bearing device of the present invention, in the bearing device including the outer ring, the inner ring, and a plurality of rolling elements rotatably arranged between the outer ring and the inner ring, A step is formed at the intersection between the peripheral surface and at least one side surface, and the insulator is covered by the step portion, so that the intersection between the inner peripheral surface of the inner ring and at least one side surface is formed. By providing the step in the portion, the formability of the insulator at the intersection can be enhanced and the film thickness can be secured. Further, even when the bearing retainer is pressed against the side surface of the inner ring, for example, at the time of assembly, the insulator sandwiched between the bearing retainer and the flat surface of the step portion has a radial direction. No directional force is applied, which can suppress breakage or peeling of the insulator.

[Brief description of the drawings]

FIG. 1 is a partial cross-sectional view of a bearing device according to a first embodiment.

FIG. 2 is an enlarged view showing a part II of the configuration of FIG. 1;

FIG. 3 is an enlarged view showing a part III in the configuration of FIG. 1;

FIG. 4 shows a configuration of a bearing device according to a second embodiment.
It is an enlarged view similar to.

FIG. 5 shows a configuration of a bearing device according to a second embodiment.
It is an enlarged view similar to.

FIG. 6 is a view showing the vicinity of an end portion of an outer ring of a bearing device capable of preventing electrolytic corrosion according to a conventional technique.

FIG. 7 is a cross-sectional view similar to FIG. 1, showing a state in which a chamfered portion 11a of an outer race 11 having an increased curvature is covered with a resin material R.

[Explanation of symbols]

 20 Bearing device 21, 31 Outer ring 22, 32 Inner ring 21b, 31b, 31b 'Outer ring step 21d, 31d, 31d' Outer ring flange surface 22b, 32b, 32b 'Inner ring step 22d, 32d, 32d' Inner ring flange Surface R insulator

Claims (2)

[Claims] 1. A bearing device comprising an outer ring, an inner ring, and a plurality of rolling elements rotatably arranged between the outer ring and the inner ring, wherein an outer peripheral surface of the outer ring and at least one side surface are provided. A bearing device in which a step is formed at the intersection of the steps, and an insulator is coated on the step. 2. A bearing device comprising an outer ring, an inner ring, and a plurality of rolling elements rotatably disposed between the outer ring and the inner ring, wherein the inner peripheral surface and at least one side surface of the inner ring are provided. A bearing device in which a step is formed at the intersection with the insulator, and an insulator is coated on the step.