Hydraulically-damped fire door closer - comprises tubular cylinder filled with hydraulic fluid, cylinder floor, and controlled piston connected on inside to connecting rod

摘要

The piston is movable against the effect of a screw pressure spring. The cylinder floor opposite to the piston full surface of a cylinder has an outflow channel issuing into the atmos. which is secured by a closure element which in turn releases an outlet aperture under the effect of unacceptably high ambient temp. The closure element is formed as an excess pressure valve, a valve controlled by a thermo-element or as a ball-shaped sealed body made of polyoxymethylene pressed into the outflow aperture. The sealed body is of the melting type and has a slightly greater dia. than the outflow aperture in which it is held with a press seat. USE/ADVANTAGE - A door closure damper, simply constructed, which even in the event of fire is able to exercise its closure function without trouble is prevented.