Impeller blade for centrifugal blower, blade-supporting rotator, impeller for centrifugal blower, and method for manufacturing impeller for centrifugal blower

Abstract

Blades of an impeller for a centrifugal blower are resinous hollow blades having hollow spaces formed in the blade interiors, and having first blade weld parts welded to plate weld surfaces of an end plate, wherein first blade weld surfaces inclined with respect to the plate weld surfaces are formed on the first blade weld parts in a state in which the first blade weld parts are disposed to face the plate weld surfaces in the axial direction.

1 . An impeller blade for a centrifugal blower in which a plurality of blades is arranged annularly around a rotational axis of a resinous blade-supporting rotator, the blades being fixed by laser welding to rotator weld surfaces formed on one side surface in the axial direction of the blade-supporting rotator the impeller blade comprising:
 a blade weld part being welded to the rotator weld surface at one end;   a blade interior having a hollow space being formed therein; and   a blade weld surface being inclined with respect to the rotator weld surface, and being formed in the blade weld part in a state in which the blade weld part is disposed to face the rotator weld surface in the axial direction.   
   
   
       2 . The impeller blade for a centrifugal blower as recited in  claim 1 , wherein the blade weld surface is inclined at an angle of 0.5 degrees to 2.5 degrees with respect to the rotator weld surface. 
   
   
       3 . The impeller blade for a centrifugal blower as recited in  claim 2 , wherein the blade weld surface is inclined to be closer to the rotator weld surface as the blade weld surface is oriented in a direction substantially opposite a direction in which an axially central portion of the blade protrudes orthogonally in the axial direction by bending the blade during application of an axially compressing load. 
   
   
       4 . The impeller blade for a centrifugal blower as recited in  claim 3 , further comprising
 a first blade surface part, and   a second blade surface part attached to the first blade surface part to form the hollow space with the first blade surface part, wherein   the blade weld part is formed to extend from the blade-supporting rotator side end of the first blade surface part toward the second blade surface part, and   the blade weld surface is inclined to be closer to the rotator weld surface as the blade weld surface is oriented toward the second blade surface part.   
   
   
       5 . The impeller blade for a centrifugal blower as recited in  claim 4 , wherein a groove or slit is formed in the blade weld part. 
   
   
       6 . The impeller blade for a centrifugal blower as recited in  claim 4 , further comprising
 a blade flat surface configured and arranged to be parallel to the rotator weld surface and disposed at position axially farther away from the rotator weld surface than the portion of the blade weld surface in proximity to the rotator weld surface, the blade flat surface is formed in the blade weld part in addition to the blade weld surface to be adjacent to the blade weld surface in a state in which the blade weld part is disposed to face the rotator weld surface in the axial direction, and a groove or slit is formed to correspond to a boundary between the blade weld surface and the blade flat surface.   
   
   
       7 . An impeller for a centrifugal blower having a plurality of impeller blades as recited in  claim 6 , comprising:
 a blade-supporting rotator being a resinous member that rotates around a rotational axis and includes rotator weld parts each having a rotator weld surface formed on one side surface in the axial direction; and   the plurality of impeller blades for a centrifugal blower being configured to be disposed annularly around the axis of the blade-supporting rotator and configured to be fixed by laser welding to the rotator weld surfaces.   
   
   
       8 . A blade-supporting rotator of an impeller for a centrifugal blower in which a plurality of resinous blades is disposed on one axial side, the blades being disposed annularly around a rotational axis and having hollow spaces in the blade interiors, and blade weld surfaces formed at one end of each the blades are fixed by laser welding to the blade-supporting rotator, the blade-supporting rotator comprising:
 rotator weld parts being welded to the blade weld surfaces in the blade side surface in the axial direction and configured to rotate around a rotational axis; and   rotator weld surfaces being inclined with respect to the blade weld surfaces, and being formed in the rotator weld parts in a state in which the rotator weld parts are disposed to face the blade weld surfaces in the axial direction.   
   
   
       9 . The blade-supporting rotator of an impeller for a centrifugal blower as recited in  claim 8 , wherein the rotator weld surfaces are configured to be inclined at an angle of 0.5 degrees to 2.5 degrees with respect to the blade weld surfaces. 
   
   
       10 . The blade-supporting rotator of an impeller for a centrifugal blower as recited in  claim 8 , wherein the rotator weld surfaces are inclined to be closer to the blade weld surfaces as the rotator weld surfaces are oriented in a direction substantially opposite a direction in which axially central portions of the blades protrude orthogonally in the axial direction by bending the blades during application of an axially compressing load. 
   
   
       11 . An impeller for a centrifugal blower having a blade-supporting rotator for a centrifugal blower as recited in  claim 8 , comprising:
 a plurality of resinous impeller blades being disposed annularly around a rotational axis and having hollow spaces in the blade interiors, and having blade weld parts having blade weld surfaces formed at one end of the blade weld parts; and   the blade-supporting rotator being disposed on the blade weld part sides of the blades, and the blade weld surfaces being fixed to the rotator by laser welding.   
   
   
       12 . The impeller for a centrifugal blower as recited in  claim 11 , wherein
 the blades include first blade surface parts, and second blade surface parts attached to the first blade surface parts to form the hollow spaces with the first blade surface parts,   the blade weld parts are formed so as to extend from the blade-supporting rotator side ends of the first blade surface parts toward the second blade surface parts, and   the rotator weld surfaces are inclined to be closer to the blade weld surfaces as the rotator weld surfaces are oriented toward the second blade surface parts.   
   
   
       13 . The impeller for a centrifugal blower as recited in  claim 11 , wherein a groove or slit is formed in each of the blade weld parts. 
   
   
       14 . The impeller for a centrifugal blower as recited in  11 , wherein
 a rotator flat surface is formed in each of the rotator weld parts in addition to the rotator weld surface to be adjacent to the rotator weld surface in a state in which the rotator weld parts are disposed to face the blade weld surfaces in the axial direction, the rotator flat surfaces being parallel to the blade weld surfaces and being disposed at positions axially farther away from the blade weld surfaces than the portions of the rotator weld surfaces in proximity to the blade weld surfaces, and   a groove or slit is formed in each of the blade weld parts to correspond to a boundary between the rotator weld surfaces and the rotator flat surfaces.   
   
   
       15 . A method for manufacturing an impeller for a centrifugal blower comprising
 preparing a resinous blade-supporting rotator to rotate around a rotational axis; and   disposing a plurality of resinous blades annularly around the axis, the plurality of resinous blades having hollow spaces formed in the blade interiors,   the blade-supporting rotator having rotator weld parts including rotator weld surfaces formed on one side surface in the axial direction,   the blades having blade weld parts on which are formed blade weld surfaces inclined with respect to the rotator weld surfaces in a state in which the blade-supporting rotator side ends are disposed to face the rotator weld surfaces in the axial direction, and   the blade weld parts being disposed to face the rotator weld surfaces in the axial direction, and the blades being fixed to the rotator weld surfaces by laser welding.   
   
   
       16 . The impeller blade for a centrifugal blower as recited in  claim 1 , wherein the blade weld surface is inclined to be closer to the rotator weld surface as the blade weld surface is oriented in a direction substantially opposite a direction in which an axially central portion of the blade protrudes orthogonally in the axial direction by bending the blade during application of an axially compressing load. 
   
   
       17 . The impeller blade for a centrifugal blower as recited in  claim 1 , further comprising
 a first blade surface part, and   a second blade surface part attached to the first blade surface part to form the hollow space with the first blade surface part, wherein   the blade weld part is formed to extend from the blade-supporting rotator side end of the first blade surface part toward the second blade surface part, and   the blade weld surface is inclined to be closer to the rotator weld surface as the blade weld surface is oriented toward the second blade surface part.   
   
   
       18 . The impeller blade for a centrifugal blower as recited in  claim 1 , wherein a groove or slit is formed in the blade weld part. 
   
   
       19 . The impeller blade for a centrifugal blower as recited in  claim 1 , further comprising
 a blade flat surface configured and arranged to be parallel to the rotator weld surface and disposed at position axially farther away from the rotator weld surface than the portion of the blade weld surface in proximity to the rotator weld surface, the blade flat surface is formed in the blade weld part in addition to the blade weld surface to be adjacent to the blade weld surface in a state in which the blade weld part is disposed to face the rotator weld surface in the axial direction, and a groove or slit is formed to correspond to a boundary between the blade weld surface and the blade flat surface.   
   
   
       20 . An impeller for a centrifugal blower having a plurality of impeller blades as recited in  claim 1 , comprising:
 a blade-supporting rotator being a resinous member that rotates around a rotational axis and includes rotator weld parts each having a rotator weld surface formed on one side surface in the axial direction; and   the plurality of impeller blades for a centrifugal blower being configured to be disposed annularly around the axis of the blade-supporting rotator and configured to be fixed by laser welding to the rotator weld surfaces.