Dynamic damper in the ductwork of an air handling system

A dynamic damper apparatus for controlling airflow through a ductwork, comprising:

• a stationary plenum panel comprising a collar terminating at a distal end that defines a through opening;
• a bracket, comprising:
• a base connected to the plenum panel;
• and
• an upstanding leg extending from the base and supporting a pivot at a predetermined distance apart from the plenum panel;
• a damper blade assembly having a damper blade defining a closure area sized larger than an entire cross-sectional area of the through opening, the damper blade supported by the pivot in alignment with the through opening and thereby selectively positionable between an open position in which the closure area is substantially parallel to the collar and thereby contactingly disengages from the plenum panel to open the through opening and permit the airflow to pass through the through opening, and a closed position in which the closure area is perpendicular to the collar and abuttingly contacts against the collar around the entire periphery of the through opening to close the through opening and thereby prevent the airflow from passing through the plenum panel;
• a spring clip, attached to the damper blade by one separable portion of a separable linkage, and another separable portion of the separable linkage attached to the plenum box, retaining the damper blade in the open position, and
• a biasing member urging the damper blade to the closed position.