Heat sensitive motor valve jack
US4619434A · kind A · utility
Assignee
Inventors
Key dates
| Filing date | Feb 17, 1981 |
| Grant date | Oct 28, 1986 |
| Priority date | — |
| Expiry date | Feb 17, 2001 |
Classification
- Technology area (CPC Y)Emerging Cross-Sectional Technologies
- CPC primaryY10T137/1834
- WIPO fieldMechanical elements
- WIPO sectorMechanical engineering
Abstract
Disclosed is a heat sensitive jack for overriding a valve including a valve body and a gate valve member connected to a valve stem which is operated by a linear actuator having an actuator body and an actuator stem connected to the valve stem extending outwardly of the actuator body, wherein the actuator stem is movable between an open and a closed position, and wherein no hazardous projectiles are formed when the stem moves to the closed position. The jack includes a cap connectable to the body and a nut axially movably disposed in the cap for movement between a first position and a second position, wherein the distance between the first and second positions is at least as great as the distance between the open and closed positions of the valve. A fusible element is provided to normally maintain the nut in the first position, but which upon being exposed to excessive temperature will allow the nut to move to the second position within the cap. A jack screw is threadably engaged in an axially movable with respect to the nut and adapted to be moved into abuttment with the jack stem when the cap is connected to the actuator body to jack the stem toward the open position.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.