Centrifugal fan device

Patent metadata

Field	Value
Publication number	US-9404502-B2
Application number	US-201213676155-A
Country	US
Kind code	B2
Filing date	Nov 14, 2012
Priority date	Dec 15, 2011
Publication date	Aug 2, 2016
Grant date	Aug 2, 2016

Abstract

A centrifugal fan device includes an impeller supported to rotate about a center axis extending in an up-down direction; a motor arranged to rotate the impeller; and a housing arranged to surround the impeller. The housing includes an intake portion positioned above the impeller and an exhaust portion positioned radially outward of the impeller. The impeller includes a base extending in a direction orthogonal to the center axis, a ring-shaped shroud positioned above the base and having a diameter which decreases as it goes upward, and a plurality of blades arranged between the base and the shroud. The housing further includes a plurality of ribs protruding from an inner surface of the intake portion toward the shroud.

First claim

What is claimed is:

1. A centrifugal fan device, comprising:
an impeller supported to rotate about a center axis extending in an up-down direction;
a motor arranged to rotate the impeller; and
a housing arranged to surround the impeller; wherein
the housing includes an intake portion positioned above the impeller and an exhaust portion positioned radially outward of the impeller;
the impeller includes a base extending in a direction perpendicular or substantially perpendicular to the center axis, a ring-shaped shroud positioned above the base and having a diameter which decreases as it goes upward, and a plurality of blades existing between the base and the shroud;
the intake portion includes a cylinder portion positioned radially inward of an upper end portion of the shroud to extend in an axial direction, a top plate portion extending radially outward from an upper end portion of the cylinder portion and an outer shell portion extending downward and radially outward from a radial outer edge of the top plate portion;
the housing further includes a plurality of ribs protruding from an inner surface of the intake portion toward the shroud; and
the ribs are spaced apart from one another at intervals in a circumferential direction of the centrifugal fan device.

2. The device of claim 1 , wherein each of the ribs includes a radial inner edge positioned radially outward of the upper end portion of the shroud, the ribs being connected to a lower surface of the top plate portion.

3. The device of claim 2 , wherein a radial distance dl between a radial inner edge of each of the ribs and an outer circumferential surface of the upper end portion of the shroud, a radial distance d 2 between a radial inner surface of the outer shell portion and the outer circumferential surface of the upper end portion of the shroud, and an axial distance d 3 between a lower surface of a section of the outer shell portion lying radially outward of the ribs and an upper surface of the shroud, satisfy a relationship of d 2 >d 3 >d 1 .

4. The device of claim 3 , wherein, when seen in a vertical cross section including the center axis and the ribs, a lower edge of each of the ribs is joined to a lower surface of the outer shell portion, and the lower surface of the section of the outer shell portion lying radially outward of the ribs is positioned lower than a lower end portion of each of the ribs.

5. The device of claim 1 , wherein, when seen in a vertical cross section including the center axis and the ribs, a lower edge of each of the ribs is joined to a lower surface of the outer shell portion, the outer shell portion including a section positioned radially outward of the ribs, the section of the outer shell portion including a lower surface positioned lower than a lower end portion of each of the ribs.

6. The device of claim 1 , wherein each of the ribs include a first rib positioned radially outward of the upper end portion of the shroud and a second rib positioned radially inward of the upper end portion of the shroud.

7. The device of claim 6 , wherein each of the ribs includes a cutout arranged between the first rib and the second rib.

8. The device of claim 6 , wherein the second rib is connected to a lower surface of the top plate portion.

9. The device of claim 1 , wherein a total number of the ribs of the housing does not equal any one of a total number of the blades of the impeller, a total number of poles of the motor, and a total number of slots of the motor.

10. The device of claim 1 , wherein the ribs include a ring-shaped rib positioned radially outward of the upper end portion of the shroud and extending in a circumferential direction, the ring-shaped rib being connected to two or more of the ribs.

11. The device of claim 1 , wherein the cylinder portion includes a lower end portion positioned lower than the upper end portion of the shroud.

12. The device of claim 1 , wherein the top plate portion includes a planar upper surface.

13. The device of claim 1 , wherein the housing is a resin molded article.

14. A centrifugal fan device, comprising:
an impeller supported to rotate about a center axis extending in an up-down direction;
a motor arranged to rotate the impeller; and
a housing arranged to surround the impeller; wherein
the housing includes an intake portion positioned above the impeller and an exhaust portion positioned radially outward of the impeller;
the impeller includes a lower impeller member and an upper impeller member positioned above the lower impeller member; and
one of the lower impeller member and the upper impeller member includes a plurality of recesses, the other of the lower impeller member and the upper impeller member including a plurality of protrusions being fitted to the recesses;
the recesses includes a single different-diameter recess differing in diameter from the remaining recesses, the protrusions including a single different-diameter protrusion differing in diameter from the remaining protrusions, the different-diameter protrusion fitted to the different-diameter recess.

15. The device of claim 14 , wherein the single different-diameter recess is a small-diameter recess smaller in diameter than the remaining recesses, the single different-diameter protrusion being a small-diameter protrusion smaller in diameter than the remaining protrusions.

16. The device of claim 14 , wherein the single different-diameter recess is a large-diameter recess larger in diameter than the remaining recesses, the single different-diameter protrusion being a large-diameter protrusion larger in diameter than the remaining protrusions.

Assignees

• Nidec Corp

Inventors

• Ishikawa Kazushi

Classifications

• F04D17/08 Primary

  Centrifugal pumps · CPC title

• F04D29/162 Primary

  of a centrifugal flow wheel · CPC title