Rolling bearing

• US 20030002759A1
• Filed: 09/14/2001
• Published: 01/02/2003
• Est. Priority Date: 06/15/2001
• Status: Active Grant

• Current Assignee: NSK Limited
• Original Assignee: NSK Limited
• Inventors: Aihara, Nariaki, Yabe, Toshikazu, Yokoyama, Keisuke, Uchiyama, Takahiko
• Granted Patent: US 6,592,264 B2
• Time in Patent Office: Days
• US Class Current: 384/484
• CPC Class Codes: B21B 31/07 Adaptation of roll neck bearings bearings in general F16C
• CPC Class Codes: B21B 31/078 Sealing devices sealings in general F16J15/00
• CPC Class Codes: B60B 27/00 Hubs non-metallic B60B5/00; of high resiliency B60B9/00
• CPC Class Codes: B61F 15/22 Sealing means preventing entrance of dust or leakage of oil
• CPC Class Codes: F16C 19/386 in O-arrangement
• CPC Class Codes: F16C 2326/02 Wheel hubs or castors
• CPC Class Codes: F16C 33/72 Sealings
• CPC Class Codes: F16C 33/78 with a diaphragm, disc, or ring, with or without resilient members F16C33/761 takes precedence

Abstract

The present invention provides a rolling bearing having a prolonged life suitable for wheel, railway vehicle and steel rolling mill comprising a sealing member which exhibits fair sealing properties even under severe conditions. A rolling bearing comprising an outer ring having an outer raceway formed on the inner surface thereof, an inner ring having an inner raceway formed on the outer surface thereof, a plurality of rolling elements rollably provided between the outer ring and the inner ring, and a sealing member for sealing the axial opening of the space between the inner surface of the outer ring and the outer surface of the inner ring in which said rolling elements are provided, characterized in that the sealing member is formed by an elastic member made of a vulcanizable rubber composition obtained by blending a carboxylated acrylonitrile-butadiene rubber with at least carbon black.

Claims

1. A rolling bearing comprising:

an outer ring having an outer raceway formed on the inner surface thereof;

an inner ring having an inner raceway formed on the outer surface thereof;

a plurality of rolling elements rollably provided between said outer ring and said inner ring so as to move one of said outer and inner rings relative to the other; and

a sealing member for sealing the axial opening of the space between the inner surface of said outer ring and the outer surface of said inner ring in which said rolling elements are provided,

wherein said sealing member is formed by an elastic member made of a vulcanizable rubber composition obtained by blending a carboxylated acrylonitrile-butadiene rubber with at least carbon black.

2. The rolling bearing as set forth in claim 1,

wherein the amount of carbon black to be blended in said rubber composition is in a range from 15 to 80 parts by weight based on 100 parts by weight of said carboxylated acrylonitrile-butadiene rubber.

3. The rolling bearing as set forth in claim 1,

wherein said rubber composition exhibits an electrical resistance of lower than 10⁵ Ω

·

cm as calculated in terms of volume resistivity.

4. The rolling bearing as set forth in claim 2,

wherein said rubber composition exhibits an electrical resistance of lower than 10⁵ Ω

·

cm as calculated in terms of volume resistivity.

5. The rolling bearing as set forth in claim 1,

wherein said rubber composition further comprises:

an electrically-conductive carbon black incorporated therein in an amount of from 2 to 40 parts by weight based on 100 parts by weight of said carboxylated acrylonitrile-butadiene rubber.

6. The rolling bearing as set forth in claim 2,

wherein said rubber composition further comprises:

an electrically-conductive carbon black incorporated therein in an amount of from 2 to 40 parts by weight based on 100 parts by weight of said carboxylated acrylonitrile-butadiene rubber.

7. The rolling bearing as set forth in claim 3,

wherein said rubber composition further comprises:

an electrically-conductive carbon black incorporated therein in an amount of from 2 to 40 parts by weight based on 100 parts by weight of said carboxylated acrylonitrile-butadiene rubber.

8. The rolling bearing as set forth in claim 4,

wherein said rubber composition further comprises:

an electrically-conductive carbon black incorporated therein in an amount of from 2 to 40 parts by weight based on 100 parts by weight of said carboxylated acrylonitrile-butadiene rubber.

9. The rolling bearing as set forth in claim 1,

wherein said carboxylated acrylonitrile-butadiene rubber further comprises a silicone oil incorporated therein.

10. The rolling bearing as set forth in claim 9,

wherein said silicone oil is a homopolymer of straight silicone oil or a polymer of two or more straight silicone oils or a modified silicone oil.

11. The rolling bearing as set forth in claim 9,

wherein said silicone oil has a dynamic viscosity of from 20 to 100,000 mm²/S at 25°

C.

12. The rolling bearing as set forth in claim 10,

wherein said silicone oil has a dynamic viscosity of from 20 to 100,000 m²/S at 25°

C.

13. The rolling bearing as set forth in claim 5,

wherein the amount of said silicone oil to be incorporated in said rubber composition is within a range from not smaller than 0.2 parts by weight to less than 30 parts by weight based on 100 parts by weight of said carboxylated acrylonitrile-butadiene rubber.

14. The rolling bearing as set forth in claim 10,

wherein the amount of said silicone oil to be incorporated in said rubber composition is within a range from not smaller than 0.2 parts by weight to less than 30 parts by weight based on 100 parts by weight of said carboxylated acrylonitrile-butadiene rubber.

15. The rolling bearing as set forth in claim 11,

wherein the amount of said silicone oil to be incorporated in said rubber composition is within a range from not smaller than 0.2 parts by weight to less than 30 parts by weight based on 100 parts by weight of said carboxylated acrylonitrile-butadiene rubber.

16. The rolling bearing as set forth in claim 12,

wherein the amount of said silicone oil to be incorporated in said rubber composition is within a range from not smaller than 0.2 parts by weight to less than 30 parts by weight based on 100 parts by weight of said carboxylated acrylonitrile-butadiene rubber.