Needle packing assembly
US5209501A · kind A · utility
Assignee
Inventor
Key dates
| Filing date | May 24, 1991 |
| Grant date | May 11, 1993 |
| Priority date | — |
| Expiry date | May 24, 2011 |
Classification
- Technology area (CPC F)Mechanical Engineering; Lighting; Heating
- CPC primaryF16K41/02
- WIPO fieldMechanical elements
- WIPO sectorMechanical engineering
Abstract
A needle packing assembly is described comprising an annular seal (1) of ultra-high molecular weight plastics material such as polyethylene. A stepped concentric passage (4) passes through the seal with a shoulder (6). The outer end of the inner wall of the passage has a sealing lip (7) formed by a 15.degree. angle with the inner wall. The lip engages a needle (8) of a valve preventing the ingress of fluid past the seal. The assembly also includes a liner (9) made of a lower molecular weight yieldable plastics material such as P.T.F.E. to provide a slidable seal with the needle (8). The liner is forced against the shoulder (6) via a packing piece (10) and disc springs (12) by a nut (14) screw-threaded onto a sleeve in a spraygun. Adjustment of the nut (14) forces the liner to expand forming a self-lubricating bearing with the needle (8) and forces the sealing lip into engagement with the needle to prevent the passage of fluid past the seal.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.