Exhaust adapter

Abstract

An exhaust adapter includes a cylindrical part for connecting an exhaust pipe of a combustion device to a collective exhaust duct; and a backflow prevention structure for preventing backflow of the exhaust from the collective exhaust duct side to the exhaust pipe side. The backflow prevention structure includes: a damper receiving part formed with an opening through which the exhaust from the exhaust pipe passes; an exhaust damper plate that opens the opening by pressure of the exhaust from the exhaust pipe and closes the opening by its own weight when there is no exhaust from the exhaust pipe; a support shaft that rotatably supports the exhaust damper plate; and a bearing part that supports the support shaft. A pair of shaft hole parts of the exhaust damper plate for inserting the support shaft is formed in a long hole shape.

What is claimed is: 
     
         1 . An exhaust adapter comprising:
 a cylindrical part for connecting an exhaust pipe of a combustion device to a collective exhaust duct for collecting and discharging exhaust of a plurality of the combustion devices; and   a backflow prevention structure for preventing backflow of the exhaust from the collective exhaust duct side to the exhaust pipe side,   wherein the backflow prevention structure comprises:   a damper receiving part formed with an opening through which the exhaust from the exhaust pipe passes;   an exhaust damper plate that opens the opening by pressure of the exhaust from the exhaust pipe and closes the opening by its own weight when there is no exhaust from the exhaust pipe;   a support shaft that rotatably supports the exhaust damper plate; and   a bearing part that supports the support shaft,   wherein the exhaust damper plate comprises a pair of shaft hole parts for inserting the support shaft, and   the pair of shaft hole parts is formed in a long hole shape that is long in a vertical direction with respect to the support shaft when the exhaust damper plate is in a posture in which the opening is closed.   
     
     
         2 . The exhaust adapter according to  claim 1 , wherein the cylindrical part is formed to have a width equal to a width of the exhaust pipe,
 the damper receiving part has an outer shape that is formed in a circular shape along an inner circumference of the cylindrical part, and   the opening is formed in a shape of a circle with a center eccentric from a center of the circular damper receiving part, or formed in a partial circular shape having a part of this circle.   
     
     
         3 . The exhaust adapter according to  claim 2 , wherein the bearing part is provided in a wide part of the damper receiving part formed by making the opening eccentric.