Components inserted into air ducts or devices which permit modification
of the air resistance of the system and consequently a change
in the air flow rate (dampers) or complete shut-off of the air
flow (valves) or control of the air flow rate and, in addition,
complete shut- off the air flow (control valves).
In particular, the following types, can be distinguished:
Multiple leaf dampers, comprising of a number of blades (or shutters)
of opposed or parallel leaf type.
Single leaf dampers (the flap being mounted at one end), commonly
called splitter dampers.
Hit-and-miss dampers, having two or more slotted slide mechanism.
Butterfly dampers, with two flaps in "V" arrangement.
Air dampers are designed for regulating air flow in rectengular
or circular ducts