Stem tip seal
US4659060A · kind A · utility
Assignee
Inventor
Key dates
| Filing date | Feb 14, 1986 |
| Grant date | Apr 21, 1987 |
| Priority date | — |
| Expiry date | Feb 14, 2006 |
Classification
- Technology area (CPC F)Mechanical Engineering; Lighting; Heating
- CPC primaryF16K1/46
- WIPO fieldMechanical elements
- WIPO sectorMechanical engineering
Abstract
A stem tip seal for a shut-off valve including a valve member adapted for selective movement axially toward and away from an associated valve seat. A generally cylindrical sleeve is carried by the valve member and has an end defining an outer annular seal surface adapted for cooperative sealing engagement with the seat. Mounted centrally within the sleeve for limited axial movement is a rigid cylindrical body that defines a first inner annular seal surface adapted for engagement with the seat at a location radially inwardly of the outer annular seal surface. Formed between the sleeve and the rigid body is an annular chamber which opens axially inwardly from a narrow slot located between the first inner annular seal surface and the outer annular seal surface. A mass of resilient packing material substantially fills the chamber and extends axially outwardly of the slot to define a second inner annular seal surface. Means are associated with the rigid body for generating pressure on the packing material when the body is forced axially toward the valve member. In addition, the first inner annular seal surface is configured to engage the seat prior to engagement by either the second inn…
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.