Shaft seal has sealing edge of protective lip corrugated in sine form, whereby ratio of wave length to amplitude of sinusoidal corrugating lies within optimum range defined by mathematical expression

摘要

The shaft seal has a sealing lip (3) and a protective lip (4), the sealing edges (31,41) of which each bear on a circumferential surface (61,62) which rotates relative to the shaft seal. The sealing edge (41) of the protective lip is corrugated in sine form, whereby the ratio of the wave length (L) to the amplitude (A) of the sinusoidal corrugating lies within a range whereby 12.5 is less than the quotient L/A which is less than 75, and preferably where 35 is less than L/A which is less than 55.