초록 ▼

A fail-safe closed damper for installation in a system of ducts. The damper includes at least one damper blade connected to a spring-loaded shaft. A power-actuated unit is employed to disengage a coupling which interconnects the spring-loaded shaft to an operating linkage. The use of the power-actua

A fail-safe closed damper for installation in a system of ducts. The damper includes at least one damper blade connected to a spring-loaded shaft. A power-actuated unit is employed to disengage a coupling which interconnects the spring-loaded shaft to an operating linkage. The use of the power-actuated unit ensures that the damper will be tripped at the appropriate predetermined temperature and will not be affected by the large frictional forces imparted on the components of the damper by the biasing spring or by such external factors as dust, humidity and dirt. The damper employs a sensor having dual sensing devices and which is centrally disposed in the duct to ensure receipt of a representative sample of airflow. The damper further includes a damper blade position indicator for sensing whether the damper blade is open or closed.

대표청구항 ▼

[ What is claimed is:] [1.] A remotely trippable and resettable damper for installation in a system of ducts, comprising:a damper blade assembly including at least one damper blade operable between an open position and a closed position and a rotatably supported shaft connected to said blade whereby

[ What is claimed is:] [1.] A remotely trippable and resettable damper for installation in a system of ducts, comprising:a damper blade assembly including at least one damper blade operable between an open position and a closed position and a rotatably supported shaft connected to said blade whereby rotation of said shaft moves said blade between said open and closed positions, said shaft being biased to drive said blade to said closed position;remotely operable control means releasably connected to said damper blade assembly for moving said damper blade between said open and closed positions and for holding said damper blade in said open position during normal operating conditions;a power-actuated unit for disengaging said damper blade assembly from said control means;means for remotely re-engaging said damper blade assembly to said control means following a tripping of said damper; anda remotely locatable sensor for sensing an environmental condition in said system, said sensor being centrally disposed in a duct of said system to ensure exposure to a representative sample of airflow, said sensor being operatively connected to said power-actuated unit to provide said power-actuated unit with a signal in response to said condition whereby said damper blade assembly is disengaged from said control means allowing said damper blade to be driven to said closed position.