Valve stem packing assembly
US4538790A · kind A · utility
Assignee
Inventors
Key dates
| Filing date | Mar 24, 1983 |
| Grant date | Sep 3, 1985 |
| Priority date | — |
| Expiry date | Mar 24, 2003 |
Classification
- Technology area (CPC F)Mechanical Engineering; Lighting; Heating
- CPC primaryF16K5/0694
- WIPO fieldMechanical elements
- WIPO sectorMechanical engineering
Abstract
A valve body has a stem passage rotatably receiving a valve stem. A packing surrounds the stem in the passage and a packing nut threaded on the stem applies axial force to radially expand the packing into sealing engagement with the stem and passage wall. Controlled slippage components interposed between the packing and packing nut allow rotation of the stem and packing nut without any rotational sliding movement against an end face of the packing. A packing support ring engages the end face of the packing adjacent the packing nut and includes a chevron surface for radially expanding the packing. A gland engages the support ring and a pair of reversely positioned spring washers are interposed between the gland and packing nut. During rotation of the stem, packing nut and spring washers, the gland rotates against the packing support ring. The chevron surface of the support ring includes notches for gripping the packing to prevent relative sliding movement therebetween. A handle is attached to the stem by a handle nut, and a spring washer interposed between the handle and handle nut prevents loosening of the handle nut.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.