Needle valve
US4575043A · kind A · utility
Assignee
Inventor
Key dates
| Filing date | Feb 8, 1985 |
| Grant date | Mar 11, 1986 |
| Priority date | — |
| Expiry date | Feb 8, 2005 |
Classification
- Technology area (CPC Y)Emerging Cross-Sectional Technologies
- CPC primaryY10T74/19902
- WIPO fieldMechanical elements
- WIPO sectorMechanical engineering
Abstract
A needle valve having improved accuracy and wear characteristics is disclosed in which the valve stem is subjected to a constant force to prevent backlash throughout its entire movement with respect to the valve seat. In addition, the needle contained within the valve stem has a tapered end which moves within the cylindrical bore in a valve seat to control fluid passing through the valve and such needle is affixed to the valve stem only at its other end remote from its tapered end. The needle thus floats for a substantial portion of its length and its tapered end is relatively flexible and free of movement. The needle is, however, angled with respect to its valve seat such that the needle physically makes contact with the internal surface of the valve seat and maintains that contact throughout its lateral movement within the valve seat.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.