JP2022139250A - Bearing with seal - Google Patents

Abstract

To provide a bearing with a seal capable of obtaining sufficient lubrication performance by a seal while ensuring high electric corrosion preventive performance with an insulation coating.SOLUTION: A bearing with a seal (bearing 100) is equipped with a seal 130 sealing a space between an outer ring 120 and an inner ring 110. The bearing with a seal has an insulation coating 140 coating either one of an outer peripheral surface 124 of the outer ring 120 and an inner peripheral surface of the inner ring 110. The insulation coating 140 also coats an inner peripheral surface of the outer ring 120 or an edge 126 of an outer peripheral surface of the inner ring 110. A surface of the insulation coating 140 coating the edge 126 is cylindrical, and the seal 130 is pressed in the insulation coating 140 coating the edge 126.SELECTED DRAWING: Figure 1

Description

The present invention relates to a sealed bearing provided with a seal for sealing between an outer ring and an inner ring.

In recent years, the development of EV (electric car) and HV (hybrid car) vehicles has progressed, and the number of high-voltage components mounted on one vehicle is increasing. When the current from the high-voltage component passes through the bearing, the surfaces of the rolling elements of the bearing and the raceway surfaces of the outer ring and the inner ring are subjected to electrolytic corrosion, which causes damage. For example, Patent Literature 1 discloses an anti-electrical corrosion rolling bearing in which an insulating coating is provided on the surface of a bearing ring. In Patent Document 1, the insulating coating is formed of polyphenylene sulfide resin containing glass fibers and a non-fibrous insulating inorganic filler.

In the rolling bearing of Patent Document 1, a plurality of circumferential grooves are formed on the surfaces of the inner ring and the outer ring, and the grooves are covered with an insulating film. As a result, the ridges formed on the insulating coating during injection molding are fitted into the circumferential grooves. Therefore, it is possible to prevent the film from slipping in the axial direction and to prevent peeling and lifting.

Patent No. 3068311

In addition to the electrolytic corrosion resistance described above, bearings are also required to prevent direct contact between metal surfaces by forming an oil film on the rolling contact surface, reduce friction on the contact surface, and prevent wear and seizure. For this reason, in bearings, it is well known that a seal is provided between the inner and outer races to cover the rolling elements from the sides, and the seal retains the grease. At this time, when a circumferential groove is formed on the inner peripheral surface of the outer ring and the outer peripheral surface of the inner ring as in Patent Document 1, and an insulating coating is fitted into the circumferential groove, the seal is fitted on the outer ring and the inner ring. groove cannot be secured.

As a method for solving the above problem, there is a configuration in which the outer peripheral surface of the outer ring and the inner peripheral surface of the inner ring are covered with an insulating coating, and a seal is fitted into the circumferential grooves formed on the inner peripheral surface of the outer ring and the outer peripheral surface of the inner ring. Conceivable.
However, with such a configuration, the outer ring and the inner ring are partially exposed between the insulating coating and the seal. Then, there is a possibility that it may become a factor of deterioration of the electrolytic corrosion resistance performance.

SUMMARY OF THE INVENTION In view of such problems, an object of the present invention is to provide a sealed bearing that can obtain sufficient lubricating performance with a seal while ensuring high electrolytic corrosion prevention performance with an insulating coating.

In order to solve the above problems, a representative configuration of the sealed bearing according to the present invention is a sealed bearing provided with a seal for sealing between the outer ring and the inner ring, wherein the outer peripheral surface of the outer ring or the inner ring is It has an insulating coating covering either one of the inner peripheral surfaces, the insulating coating covering the inner peripheral surface of the outer ring or the outer peripheral surface of the inner ring up to the edge, and the surface of the insulating coating covering the edge is cylindrical. , the seal is pressed into an insulating coating covering the edge.

In the above configuration, the outer peripheral surface of the outer ring and the inner peripheral surface of the inner ring are covered with an insulating coating up to the edge thereof. As a result, since the outer ring and the inner ring are not exposed, high electrolytic corrosion prevention performance can be ensured. The seal is then pressed into an insulating coating covering the edges. Therefore, even when the outer peripheral surface of the outer ring and the edge of the inner peripheral surface of the inner ring are covered with an insulating coating, a seal can be provided. As a result, the space between the outer ring and the inner ring is sealed and grease is retained inside the seal, thereby reducing friction due to rotation during operation and preventing wear and seizure. Therefore, it becomes possible to obtain sufficient lubricating performance.

The core bar of the seal may have a cylindrical portion that abuts on the insulating coating that covers the edge. With such a configuration, the contact area between the metal core of the seal and the insulating coating can be increased, so that the seal can be held well.

ADVANTAGE OF THE INVENTION According to this invention, it becomes possible to provide the bearing with a seal which can obtain sufficient lubricating performance by a seal, ensuring high electrolytic-corrosion prevention performance by an insulating film.

It is a figure explaining the bearing with a seal concerning this embodiment. It is a figure explaining the modification of a seal|sticker. It is a diagram illustrating a bearing provided with both an insulating coating and a seal by extending the conventional technical idea.

Preferred embodiments of the present invention will be described in detail below with reference to the accompanying drawings. The dimensions, materials, and other specific numerical values shown in these embodiments are merely examples for facilitating understanding of the invention, and do not limit the invention unless otherwise specified. In the present specification and drawings, elements having substantially the same function and configuration are denoted by the same reference numerals to omit redundant description, and elements that are not directly related to the present invention are illustrated or described. omitted.

FIG. 3 is a diagram illustrating a bearing provided with both an insulating coating and a seal by extending the conventional technical idea. In the bearing 10a shown in FIG. 3(a) and the bearing 10b shown in FIG. 3(b), constituent elements having the same functions are denoted by the same reference numerals and descriptions thereof are omitted. 3(a) and 3(b) show balls of the same size.

A bearing 10 a shown in FIG. 3( a ) includes balls 16 as rolling elements between an inner ring 12 and an outer ring 14 . Balls 16 are retained by retainers 18 . A seal 20 seals between the outer ring 14 and the inner ring 12 . The seal 20 is composed of a core 22 and a lip 24 supporting the core 22 .

In the bearing 10 a , the outer peripheral surface of the outer ring 14 is covered with an insulating coating 30 . In such a configuration, since the seal groove 32 is provided in the insulating coating 30, it becomes impossible to forcibly remove the insulating coating 30 during molding. In addition, since the insulating coating 30 has a large coefficient of linear expansion, the amount of interference between the insulating coating 30 and the seal 20 is likely to change, making it difficult to maintain a stable assembled state.

In the bearing 10b shown in FIG. 3B, the outer ring 14 is provided with a seal groove 14a. With such a configuration, since the edge 14b of the inner diameter surface of the outer ring 14 is not covered with the insulating coating 30, high-frequency electricity flows between it and the housing, resulting in a decrease in insulation performance.

On the other hand, the present invention provides a bearing with a seal that can obtain sufficient lubricating performance with a seal while ensuring high electrolytic corrosion prevention performance with an insulating coating, by the following configuration.

FIG. 1 is a diagram illustrating a sealed bearing (hereinafter referred to as a bearing 100) according to this embodiment. The bearing 100 of this embodiment is a ball bearing. In addition, although the structure which coat|covers the outer ring|wheel 120 with the insulation film 140 is illustrated in this embodiment, it is not limited to this. A similar effect can be obtained with a configuration in which the inner ring 110 is covered with the insulating coating 140 .

As shown in FIG. 1, bearing 100 includes balls 102 as rolling elements between inner ring 110 and outer ring 120 . Ball 102 is retained by retainer 104 . A seal 130 seals between the inner ring 110 and the outer ring 120 .

In this embodiment, the seal 130 is composed of a metal core 132 and a lip 134 supported thereon. A seal groove 112 is formed in the inner ring 110 and a lip 134 is in contact therewith.

On the other hand, a resin groove 122 is formed in the edge 126 of the inner peripheral surface of the outer ring 120 . "Inner peripheral edge 126" means outside the shoulder 121 of the raceway surface. As shown in FIG. 1, in the bearing 100 of this embodiment, the outer peripheral surface of the outer ring 120 is covered with an insulating coating 140 . In particular, in this embodiment, the insulating coating 140 extends from the outer peripheral surface 124 of the outer ring 120 to the side surface 125 and continuously covers the edge 126 of the inner peripheral surface. An end portion 142 of the insulating coating 140 enters the resin groove 122 like a claw. As a result, the outer ring 120 is covered with the insulating coating 140 up to the edge 126 of the inner peripheral surface. Therefore, since the outer ring 120 is not exposed, high electrolytic corrosion prevention performance can be ensured.

Further, in the bearing 100 of the present embodiment, the insulating coating 140 covering the edge 126 of the inner peripheral surface of the outer ring 120 is formed with a contact surface 144 having a cylindrical surface. On the other hand, the core metal 132 of the seal 130 is composed of an annular sealing portion 132a and a cylindrical portion 132b rising from the edge of the sealing portion 132a. As can be seen from FIG. 1, one side of the cored bar 132 has an L-shaped cross section. The seal 130 is attached to the outer ring 120 by fitting the cylindrical portion 132 b of the core metal 132 of the seal 130 into the cylindrical contact surface 144 of the insulating coating 140 .

Thus, the seal 130 can be provided even when the outer ring 120 is covered up to the edge of the outer peripheral surface 124 with the insulating coating. Therefore, it is possible to seal between the outer ring 120 and the inner ring 110, retain grease (not shown) inside the seal 130, and reduce rotational friction during operation. Therefore, it is possible to obtain sufficient lubricating performance.

Further, since both the contact portions of the seal 130 and the insulating coating 140 are cylindrical, a large contact area can be secured between them. Therefore, even though it is press-fit, the posture can be stabilized, and falling off can be prevented.

FIG. 2 is a diagram illustrating a modification of the seal. In the seal 130a shown in FIG. 2(a), a spring portion 136 is provided between a sealing portion 132a and a cylindrical portion 132b. In the seal 130b shown in FIG. 2B, a flexible portion 138 is provided between the sealing portion 132a and the cylindrical portion 132b. As a result, the spring portion 136 and the flexible portion 138 function as stress relief when the contact of the lip 134 changes due to the difference in the amount of tightening. Therefore, it is possible to bring the core metal of the seal into contact with the insulating coating 140 in a stable state.

In this embodiment, the outer peripheral surface 124 of the outer ring 120 is covered with the insulating coating 140 as an example, but the present invention is not limited to this. Even with a configuration in which the inner peripheral surface of inner ring 110 is covered with insulating coating 140, the effects described above can be obtained.

Although the preferred embodiments of the present invention have been described above with reference to the accompanying drawings, it goes without saying that the present invention is not limited to such examples. It is obvious that a person skilled in the art can conceive of various modifications or modifications within the scope described in the claims, and these also belong to the technical scope of the present invention. Understood.

INDUSTRIAL APPLICABILITY The present invention can be used as a sealed bearing provided with a seal that seals between the outer ring and the inner ring.

DESCRIPTION OF SYMBOLS 10a... Bearing, 10b... Bearing, 12... Inner ring, 14... Outer ring, 14a... Seal groove, 14b... Edge, 16... Ball, 18... Cage 20... Seal, 22... Core metal, 24... Lip, 30... Insulating coating , 32... Seal groove, 100... Bearing, 102... Ball, 104... Cage, 110... Inner ring, 112... Seal groove, 120... Outer ring, 121... Shoulder of raceway surface, 122... Resin groove, 124... Outer peripheral surface, 125 Side surface 126 Edge 130 Seal 130a Seal 130b Seal 132 Metal core 132a Sealing portion 132b Cylindrical portion 134 Lip 136 Spring portion 138 Flexible portion 140 ... Insulating coating, 142 ... Edge of insulating coating, 144 ... Contact surface

Claims (2)

A sealed bearing comprising a seal that seals between an outer ring and an inner ring,
Having an insulating coating covering either the outer peripheral surface of the outer ring or the inner peripheral surface of the inner ring,
The insulating coating covers the inner peripheral surface of the outer ring or the edge of the outer peripheral surface of the inner ring,
A bearing with a seal, wherein the surface of the insulating coating covering the edge is cylindrical, and the seal is press-fitted into the insulating coating covering the edge. 2. The bearing with seal according to claim 1, wherein the core metal of the seal has a cylindrical portion that abuts on the insulating coating that covers the edge.

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