| 摘要 |
<p>A fluid flow control damper assembly having a damper vane and a piston actuator is relatively easy to install when the outer surface of a duct is inaccessible. The piston actuator includes a powder metal piston, lacking an elastomeric (for example, rubber) seal, that is closely received within a glass cylinder. The glass cylinder has a fitting that closes one end of the cylind er and is connectable to a pneumatic control system. A drive rod is connected between the piston and the damper vane to move the damper vane between an open position and a closed position.</p> |
