Bidirectional hydrodynamic polytetrafluoroethylene seal
US3984113A · kind A · utility
Assignee
Inventor
Key dates
| Filing date | Jan 17, 1975 |
| Grant date | Oct 5, 1976 |
| Priority date | — |
| Expiry date | Jan 17, 1995 |
Classification
- Technology area (CPC F)Mechanical Engineering; Lighting; Heating
- CPC primaryF16J15/3244
- WIPO fieldMechanical elements
- WIPO sectorMechanical engineering
Abstract
A bidirectional hydrodynamic polytetrafluoroethylene shaft seal and a method for manufacture thereof. An annular polytetrafluoroethylene sealing member has a radially outer annular planar portion and a radially inner annular shaft-sealing non-planar portion inclined to the planar portion. An annular metal case clamps the planar portion in place, and the inner portion has a shaft-engaging side with an inner edge and a pair of spaced-apart coaxial projecting circular ribs. A first circular rib lies adjacent to the inner edge, and a second circular rib lies farther from the inner edge. A series of curved segmental ribs, each having a pair of ends spaced toward the first rib from the second rib and curved in between its ends toward the first rib, extend in to and intersect the first rib. To make the seal, a flat annular wafer of polytetrafluoroethylene of constant thickness is coined at an annular inner portion adjacent the inner periphery to provide the first and second circular ribs and a series of straight segmental ribs, each of which extends tangential to the inner side of the inner rib, thereby intersecting the inner rib, the crest of the straight ribs projecting out further than…
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.