Opening and shutting apparatus for flow control

Abstract

An opening and shutting apparatus for a flow control to adjust a fluid flow inside a duct, especially, in which a kinematical structure is used, and so the sum of the moment acting on the knob on closing-up the inside of the duct is forced to come to zero, so that the inside of the duct can be stably closed up without special locking projection or spring, etc.

1 . An opening and shutting apparatus for a flow control, comprising: 
 a damper door opening and shutting a path inside a duct;    a link configured to be connected with an end of the damper door and in having a sliding groove formed therein; and    a knob having a coupling projection thereon configured to be connected with the sliding groove of the link,    wherein a line normal to a point farthest from a rotational center of the knob among contact points between the sliding groove and the coupling projection of the knob passes through the rotational center of the knob when the duct inside is closed up.    
     
     
         2 . The opening and shutting apparatus according to  claim 1 , wherein the sliding groove of the link has a bent shape.