Flame-arresting or smoke-clearing valve device operating by closure and opening respectively

Abstract

The valve device adjustably controls air flow through a mechanical ventilation duct, blocks propagation of flames through the duct, and selectively exhausts smoke through the duct. An air extraction terminal sleeve communicates with the ventilation duct and is provided with an outwardly facing valve seat. A support is mounted in the sleeve inwardly of the valve seat and an elongated guide extends adjustably through the support. An obturator is mounted on the guide outwardly of the support for adjustably controlling the flow area into the terminal sleeve, and includes an outwardly convex dome member fixedly secured to the outer end of the guide, and an inwardly convex valve member having conforming seating engagement with the dome member and arranged to conformingly engage the valve seat to block flow into the terminal sleeve. The valve member is slidable on the guide, and a pair of oppositely wound coil springs surround the guide within the obturator and bias the valve member to separate from the dome member to engage the valve seat. A pin engaged with the guide restrains separation of the dome and valve members and releases such restraint responsive to detection of a fire whereby the valve member is disengaged from the dome member to engage the valve seat to block the terminal sleeve. The interior surfaces of the dome and valve members are lined with insulating layers, and the valve member has apertures therein covered by the associated insulating layer. By removal of this insulating layer and disengagement of the pin, the valve member may be separated from the dome member so that smoke may be exhausted through the duct.

Dependencies are inferred from the claim text.