JPH0988972A - Resin insulated bearing - Google Patents

Abstract

PROBLEM TO BE SOLVED: To prevent any crack in a resin layer from occurring by forming this resin layer ranging from an outer diametral surface of an outer ring to an end face, installing a recess part in a chamfer connecting the outer diametral surface and the end face, and fitting a projecting part of a resin layer sticking part in the recess part. SOLUTION: A resin layer 5 uses, for example, synthetic resins such as polyphenylene sulfide resin, polymaide resin, urethane resin, acryl resin, epoxy resin or the like, and it is integrally molded as one body in an outer ring 1 by means of injection molding. Two circumferential grooves 1a1 and 1b1 are formed in an outer diametral surface 1a and an end face 1b of the outer ring 1, and two circumferential grooves 1c1 and 1c2 are concentrically formed in a radiused-form chamfer 1c connecting the end face 1b and the outer diametral surface 1a of the outer ring 1. Subsequently two projecting aprts 5c1 and 5c2 of the resin layer 5 are fitted in these circumferential grooves 1c1 and 1c2 , whereby even in the case where any of external force or impact force has acted on the chamfer 1c, the resin layer 5 is restained to an outer ring base material and its slide is prevented, so that any crack is hard to occur in the resin layer 5.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a resin insulated bearing used in places where electric corrosion due to leakage current is a problem, such as railway vehicles and various industrial motors.

[0002]

2. Description of the Related Art For example, in a railroad vehicle such as an electric locomotive or an electric passenger car that travels with electric power as a power source, a grounding collector for grounding the leak current is provided so that vehicle parts are not damaged by the current leaking from the motor. An electric device is provided between the vehicle body and the vehicle. However, a slight leakage current may flow into the bearing that supports the axle for some reason. In this case, a leak current may cause a spark between the rolling element of the bearing and the raceway surface to cause electrolytic corrosion.

As a means for preventing the above-described electrolytic corrosion of the bearing, there has been known a structure in which the outer ring 11 is covered with a resin layer 12 which is an insulating material, as shown in FIG. The resin layer 12 extends from the outer diameter surface 11a of the outer ring 11 to both end surfaces 1
1b, in order to improve the adhesion with the outer ring base material, as shown in an enlarged view in FIG. 2 (b), the outer circumferential surface 11a and the end surface 11b of the outer ring 11 are provided with circumferential grooves 11a1 and 11b1, respectively. The protrusions 12a and 12b on the attachment surface of the layer 12 are fitted into the circumferential grooves 11a1 and 11b1, respectively.

[0004]

As shown in an enlarged view in FIG. 2 (b), a chamfered portion 11c is usually provided at a portion connecting the outer diameter surface 11a and the end surface 11b of the outer ring 11. . The chamfered portion 11c is often formed in an R shape. When any external force or impact force acts on the portion of the resin layer 12 that covers the chamfered portion 11c, the chamfered portion 1
The resin layer 12 may be cracked at a boundary portion E between the 1c and the outer diameter surface 11a. For example, the bearing may be inadvertently dropped when the bearing is transported, assembled, or removed, but the falling posture is bad and the chamfered portion 11c.
It has been experienced that the resin layer 12 cracks when the vehicle collides with the ground or the like, when the drop height is high, or when the collision partner is hard.

As described above, cracks in the resin layer 12 are likely to occur at the boundary portion E between the chamfered portion 11c and the outer diameter surface 11a. This is because when an impact force or the like is applied to the portion of the resin layer 12 that covers the chamfered portion 11c, especially when the chamfered portion 11c has an R shape as shown in FIG. This is because it is slippery, and stress concentration occurs at the boundary portion E of the resin coating 12 due to this slippage.

The present invention is intended to effectively prevent the crack of the resin layer as described above.

[0007]

In order to solve the above problems, the present invention provides a resin-insulated bearing in which a resin layer is formed from the outer diameter surface to the end surface of an outer ring, in a chamfered portion connecting the outer diameter surface and the end surface. A configuration is provided in which a concave portion is provided and the convex portion of the resin layer attachment surface is fitted into the concave portion.

The recessed portion provided in the chamfered portion may have any of a circumferential groove, a cross groove, and a recess. In the circumferential groove,
A single-row groove, a double-row groove (concentric groove), and a spiral groove are included. The intersecting groove is a groove formed by, for example, loretting. The depression includes a bottomed hole shape processed by a drill or the like, and a minute recess formed by surface treatment processing such as shot blasting or tumbler processing.

[0009]

BEST MODE FOR CARRYING OUT THE INVENTION The embodiment shown in FIG. 1 is an application of the present invention to a cylindrical roller bearing. The cylindrical roller bearing includes an outer ring 1, an inner ring 2, a plurality of cylindrical rollers 3 interposed between the inner and outer rings 1, 2 and a cage 4 for holding the cylindrical rollers 3 at equal intervals around the circumference.
The outer ring 1 is composed of a resin layer 5 formed from the outer diameter surface 1a to both end surfaces 1b.

As shown in an enlarged view in FIG. 1B (the drawing shows only one end portion A of the outer ring 1, the other end portion B has the same structure), and the outer diameter of the outer ring 1 is the same. Face 1a and end face 1b
Circumferential grooves 1a1 and 1b1 are formed in the end surface 1b of the outer ring 1.
Two circumferential grooves 1c1 and 1c2 are concentrically formed in the R-shaped chamfered portion 1c which connects the outer diameter surface 1a and the outer diameter surface 1a. The circumferential groove 1c1 is located substantially in the center of the chamfered portion 1c, and the circumferential groove 1c2 is located near the boundary E between the chamfered portion 1c and the outer diameter surface 1a. Further, in this embodiment, the circumferential groove 1a2 is formed on the outer diameter surface 1a so as to sandwich the circumferential groove 1c2 and the boundary portion E therebetween. The depth of the circumferential grooves 1c1, 1c2, 1a2 is about 1 mm
The width and width are about 1 mm. Circumferential groove 1a1, 1b1
Are slightly larger in depth and width than the circumferential grooves 1c1, 1c2, 1a2 (about 1.2 mm).

The resin layer 5 is formed by injection molding (insert molding) using a synthetic resin such as polyphenylene sulfide resin (PPS), polyamide resin (PA: polyamide 66, polyamide 46, etc.), urethane resin, acrylic resin, epoxy resin, etc. ) Is integrally formed with the outer ring 1. A reinforcing material such as glass fiber may be added to the PPS resin or the like for reinforcement.

At the time of molding, the molten resin is the circumferential groove 1a of the outer ring 1.
1, 1b1, 1c1, 1c2, 1a2 are filled, and convex portions 5a, 5b, 5c1, 5c2, 5 are formed on the adhesion surface of the resin layer 5.
c3 is formed. And after the molten resin solidifies,
By fitting these convex portions into the circumferential grooves, the adhesion of the resin layer 5 to the outer ring base material is enhanced. Especially,
By fitting the convex portions 5c1 and 5c2 of the resin layer 5 into the circumferential grooves 1c1 and 1c2 of the chamfered portion 1c, respectively, even when some external force or impact force acts on the chamfered portion 1c,
Since the resin layer 5 is restrained with respect to the outer ring base material and its slip is prevented, cracks are unlikely to occur in the resin layer 5. Further, in this embodiment, the fitting structure of the convex portion 5c2 and the circumferential groove 1c2 and the convex portion 5c3 and the circumferential groove 1a2 are provided with the boundary portion E where the crack of the resin layer 5 is likely to occur sandwiched therebetween. Therefore, the occurrence of cracks can be prevented more effectively.

[0013]

As described above, according to the present invention, the chamfered portion connecting the outer diameter surface and the end surface of the outer ring is provided with the concave portion, and the convex portion of the resin layer attachment surface is fitted into the concave portion. Therefore, even if some external force or impact force is applied to the chamfered portion, the resin layer is restrained with respect to the outer ring base material and the slip is less likely to occur, so that the occurrence of cracks in the resin layer is effectively prevented. It

[Brief description of drawings]

FIG. 1 is a cross-sectional view (FIG. A) showing an embodiment and an enlarged cross-sectional view (FIG. B) of an A portion.

FIG. 2 is a cross-sectional view (FIG. A) showing a conventional configuration, and an enlarged cross-sectional view of a portion A (FIG. B).

[Explanation of symbols]

 1 Outer Ring 1a Outer Diameter Surface 1b End Surface 1c Chamfer 1c1 Circumferential Groove (Concave) 1c2 Circumferential Groove (Concave) 5 Resin Layer 5c1 Convex 5c2 Convex

Claims (2)

[Claims] 1. A resin-insulated bearing having a resin layer formed from the outer diameter surface to the end surface of an outer ring, wherein a chamfered portion connecting the outer diameter surface and the end surface is provided with a concave portion, and a convex portion on the adhesion surface of the resin layer is provided. A resin-insulated bearing fitted in the recess. 2. The resin-insulated bearing according to claim 1, wherein the recess is one of a circumferential groove, a cross groove, and a recess.