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Fan wheel

Imported: 24 Feb '17 | Published: 06 Jan '04

Eugen Schloetzer

USPTO - Utility Patents

Abstract

An electric fan having an electric motor and a fan wheel connected to the electric motor. The fan wheel has a hub and fan blades extending from the hub. The fan blades include a proximal section at the hub, a distal section and a middle section. The proximal section has a flat surface at a trailing edge of the blade. The trailing edge at the distal section is curved with an angle of curvature of about 10°. The trailing edge at the middle section is curved with an angle of curvature of about 36°. When the fan wheel is rotated by the electric motor at a constant speed, air pushed by each of the fan blades is propelled at a substantially same velocity and direction from the blade measured across a radial length of the blade.

Description

BRIEF DESCRIPTION OF THE DRAWINGS

The foregoing aspects and other features of the present invention are explained in the following description, taken in connection with the accompanying drawings, wherein:

FIG. 1 is a schematic view of an electric fan incorporating features of the present invention;

FIG. 1A is a perspective view of the fan wheel of the fan shown in FIG. 1;

FIG. 2 is a top plan view of one of the fan blades of the fan wheel shown in FIG. 1A;

FIG. 3 is a side elevational view of the fan blade shown in FIG. 2;

FIG. 4 is a cross sectional view of the fan blade shown in FIG. 2 taken along line

4

4;

FIG. 5 is a cross sectional view of the fan blade shown in FIG. 2 taken along line

5

5;

FIG. 6 is a cross sectional view of the fan blade shown in FIG. 2 taken along line

6

6; and

FIG. 7 is a perspective view of an alternate embodiment of a fan wheel incorporating features of the present invention.

Claims

1. A fan wheel comprising:

2. A fan wheel as in claim 1 wherein the first angle is about 10°.

3. A fan wheel as in claim 1 wherein the second angle is about 36°.

4. A fan wheel as in claim 1 wherein each blade further comprises a third section located adjacent the center section, the third section having a forward facing substantially flat surface located at the trailing edge, the surface being aligned in a plane perpendicular to a center axis of the center section.

5. A fan wheel as in claim 4 wherein the first section is substantially flat.

6. A fan wheel as in claim 5 wherein the second section is curved with a substantially uniform thickness.

7. A fan wheel as in claim 6 wherein the third section is curved with a steeper curvature than the second section.

8. A fan wheel comprising:

9. A fan wheel as in claim 8 wherein the surface is located along a plane perpendicular to a center axis of the center hub section.

10. A fan wheel as in claim 8 wherein each blade comprising a distal section proximate a tip of the blade and a middle section, wherein the distal section is curved at the trailing edge with a first angle relative to a tangent to the distal section at the trailing edge of between about 7°-13°, and wherein the middle section is curved at the trailing edge with a second angle relative to a tangent to the middle section at the trailing edge of between about 33°-39°.

11. A fan wheel as in claim 10 wherein the first angle is about 10°.

12. A fan wheel as in claim 10 wherein the second angle is about 36°.

13. A fan wheel as in claim 10 wherein the distal section is substantially flat.

14. A fan wheel as in claim 10 wherein the middle section is curved with a substantially uniform thickness.

15. A fan wheel as in claim 14 wherein the proximal section has a substantially uniform thickness and is curved with a steeper curvature than the middle section.

16. An electric fan comprising:

17. An electric fan as in claim 16 wherein the distal section is substantially flat.