| 摘要 |
PURPOSE: To lengthen the life of a radial bearing by providing one or more helical second cut parts on the front surface of a seal disc, extending the width of the back surface, activating dispersion of frictional heat, and preventing excessive thermal decomposition of lubricating oil. CONSTITUTION: A seal disc 2 is manufactured as a flat annular disc, inside diameter section of the disc is axially drawn towards the front surface side in a heated press die and extended into a trumpet shape. At least one helical second cut part 8 is provided on the front surface of the seal disc 2, this second cut part 8 is extended in parallel with a first cut part 6, and a clearance is arranged between them. The pressure of the second cut part 8 winders the back surface, so that the radiation of frictional heat generated by the rotation of a shaft is proper and, therefore, lubricating oil is not superheated to be decomposed consequently to let a radial shaft seal kept long. |
