| 摘要 |
<p>A doorlatch knob assembly has a knob insert of a hollow knob projecting through a door mounted rose secured rotatable by a drive washer which, in turn, receives the outer end of a doorlatch connected spindle projecting outwardly through the drive washer drivingly engaged therewith, through the insert and into the hollow knob. A fire resistant shield is closely telescoped and engaged with the insert receiving the spindle outer end therein so as to close off the previous opening from the hollow knob inwardly and preserve the integrity of the spindle retainment of the doorlatch mechanism against flame penetration upon heat destruction of the knob. The shield may have formation engaging the spindle outer end to aid the drive washer for rotatably driving the spindle. Where a turnbutton shaft is involved, it will also be formed of fire resistant material and will be closely telescoped by the outer end of the shield, otherwise the outer end of the shield will be closed.</p> |
