Shaft and sealing ring

US4709930A · kind A · utility

Assignee

• Firma Carl Freudenberg · DE

Inventor

• Hans Forch · Birkenau, DE

Key dates

• Filing date: Mar 6, 1985
• Grant date: Dec 1, 1987
• Expiry date: Mar 6, 2005

Classification

• Technology area (CPC F): Mechanical Engineering; Lighting; Heating
• CPC primary: F16J15/3244
• WIPO field: Mechanical elements
• WIPO sector: Mechanical engineering

Abstract

In the combination of a shaft with a polymeric ring having a sealing surface which flares against a counter surface on the shaft to form a dynamic sealing zone therebetween upon relative rotation of the shaft and ring, both the sealing and counter surfaces have hydrodynamically-acting feed-back elements for pumping fluid which seeps between the surfaces upon the relative rotation. The resultant, net axial component of pumping actions of the elements is in one axial direction along the shaft to pump the fluid back into the space from which it came, but the elements have different pumping actions. The different pumping actions produce a fluid circulation in the dynamic sealing zone which inhibits seal-wearing granular deposits.