Variable air volume control apparatus

Abstract

The present invention relates to a variable air volume control apparatus capable of effectively reducing air overflow concentrated at one side due to a damper blade biased according to an opening angle of the damper blade, thereby precisely adjusting the air volume. The variable air volume control apparatus includes a damper blade disposed rotatably inside the duct to open or close an air flow path and an actuator for rotating the damper blade. The apparatus also includes means for dividing the air flow path inside the duct at the air inlet side into an upper region and a lower region and exerting resistance to the air flow between the means and the biased damper blade. The invention effectively suppresses the air overflow occurring at high opening ratio of the damper blade with simple structural improvements, thereby accurately and precisely adjusting the air volume.

1 . A variable air volume control apparatus for adjusting air flow volume in a duct comprising:
 a damper blade disposed rotatably in the duct to open or close an air flow path;   an actuator for rotating the damper blade; and   means for dividing the air flow path in the duct at an air inlet side into an upper region and a lower region with respect to a rotation axis of the damper blade, wherein resistance is exerted to an air flow between a portion of the damper blade biased toward the air inlet side and the flow path dividing means.   
     
     
         2 . The variable air volume control apparatus according to  claim 1 , wherein the flow path dividing means comprises a separation plate disposed in a front side of the damper blade to dichotomize the duct. 
     
     
         3 . The variable air volume control apparatus according to  claim 1 , wherein the flow path dividing means has a diameter 0.5 times larger than that of the duct. 
     
     
         4 . The variable air volume control apparatus according to  claim 2 , wherein the separation plate has sealing material at an end thereof, the sealing material providing sealing between the end of the separation plate and a portion of the rotation axis of the damper blade. 
     
     
         5 . The variable air volume control apparatus according to  claim 1 , wherein the rotation axis of the damper blade and the air flow path dividing means are shifted upward or downward from the center of the duct. 
     
     
         6 . The variable air volume control apparatus according to  claim 5 , further comprising a flow path blocking means for blocking an open region between an outer surface of the damper blade and the duct. 
     
     
         7 . The variable air volume control apparatus according to  claim 6 , wherein the flow path blocking means comprises a blocking plate in a crescent shape fixed to the duct. 
     
     
         8 . The variable air volume control apparatus according to  claim 1 , wherein the duct has a rectangular cross-section. 
     
     
         9 . A variable air volume control apparatus comprising:
 a damper blade disposed rotatably inside the duct to open or close an air flow path;   an actuator for rotating the damper blade;   means for expanding the air flow path according to an angle of the damper blade that opens or closes the duct; and   an air flow path dividing means for dividing the air flow path inside the duct in an air inlet side of the damper blade into an upper region and a lower region with respect to a rotation axis of the damper blade, wherein resistance is exerted to air flow between a apportion of the damper blade biased toward the air inlet side and the flow path dividing means.   
     
     
         10 . The variable air volume control apparatus according to  claim 17 , wherein the flow path regulating means comprises a curved surface which compensates and expands the air flow path such that the air flow path is open in proportion to an open angle of the damper blade at an angle of less than 30° rather than by a function of “1-COS θ” of the open angle. 
     
     
         11 . The variable air volume control apparatus according to  claim 10 , wherein the air flow path regulating means comprises a ring structure that is installable on an inner surface of said duct, and the damper blade has a circumference the same as the inner circumference of the said ring structure. 
     
     
         12 . The variable air volume control apparatus according to  claim 10 , wherein the flow path regulating means is formed to compensate an opening ratio of (θ/90)-(1-COS θ) at an angle of less than 30°, where θ is an arbitrary angle to which the damper blade is opened. 
     
     
         13 . The variable air volume control apparatus according to  claim 10 , wherein the rotation axis of the damper blade and the flow path dividing means are shifted upward or downward from the center of the duct, and the air flow path regulating means is disposed between an outer edge of the damper blade and the duct. 
     
     
         14 . The variable air volume control apparatus according to  claim 17 , wherein the air flow path regulating means comprises a ring structure that is installable on an inner surface of said duct, and the damper blade has a circumference the same as an inner circumference of the ring structure. 
     
     
         15 . The variable air volume control apparatus according to  claim 17 , wherein the flow path regulating means is formed to compensate an opening ratio of (θ/90)-(1-COS θ) at an angle of less than 30°, where θ is an arbitrary angle to which the damper blade is opened. 
     
     
         16 . The variable air volume control apparatus according to  claim 17 , wherein the rotation axis of the damper blade and the flow path dividing means are shifted upwardly or downwardly or forwardly or rearwardly from the center of the duct, and the air flow path regulating means is disposed between an outer edge of the damper blade and the duct. 
     
     
         17 . A variable air volume control apparatus for adjusting air flow volume in a duct comprising:
 an air flow duct;   a damper blade disposed pivotally within said duct to open or close an air flow path;   an actuator for rotating the damper blade;   an air flow path regulating means for regulating the air flow according to an angle of the damper blade that opens or closes said duct, said means comprising a controller operated actuator for adjusting the opening angle of the damper blade during operations of the control apparatus;   and air flow path dividing means for dividing the air flow path inside said duct in an air inlet side of the damper blade into an upper region and lower region with respect to a rotation axis of the damper blade;   said air flow path dividing means comprising a separation plate extending from the great part of the approximate axis of rotation of said damper blade along the width of said damper blade and upstream in the said duct and arranged approximately aligned with the flow of air through the said air inlet side of the said duct; and   wherein air flow is blocked and affected by great resistance in an closed space enclosed by a portion of the damper blade bias towards the air inlet side and the flow path dividing means during operations of the said control apparatus and the air overflow occurring at a high opening ratio of the damper blade is suppressed to prevent excessive air flow.   
     
     
         18 . The variable air volume control apparatus according to  claim 17 , wherein the separation plate has sealing material at an end thereof, the sealing material providing sealing between the end of the separation plate and a portion of the rotation axis of the damper blade.