Pilot valve with fusible lockout knob
US4469119A · kind A · utility
Assignee
Inventors
Key dates
| Filing date | Mar 29, 1982 |
| Grant date | Sep 4, 1984 |
| Priority date | — |
| Expiry date | Mar 29, 2002 |
Classification
- Technology area (CPC Y)Emerging Cross-Sectional Technologies
- CPC primaryY10T137/8663
- WIPO fieldMechanical elements
- WIPO sectorMechanical engineering
Abstract
There is disclosed an apparatus for manually locking a pilot valve in an "in service" position independent of an actuating, or pilot fluid pressure. The apparatus may be either manually disengaged or will be automatically disengaged whenever the ambient temperature exceeds a predetermined level. The device includes a valve manipulating knob attached to the exterior end of a valving element for manually shifting the element from a normally closed position to the in service position. The knob includes an "L" shaped locking member which conforms to the contour of the knob, and is adapted to pivot towards the valve body and lock the valving element out in the "in service" position. This pivotal member includes an indicating surface visible from the front when the valving element is locked in an "in service" position. The locking member is comprised of a fusible material selected to yield at a predetermined temperature so as to return the valve to an operating mode responsive to the pilot fluid pressure.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.