Fan and impeller thereof

Abstract

A fan includes an impeller and a motor. The impeller includes a hub and a plurality of blades. The hub has a top portion, a connection portion, and at least one airflow-guiding portion. The top portion is connected to the connection portion. The blades are disposed around the connection portion. The motor is disposed corresponding to the impeller and used to drive the impeller to rotate. The airflow-guiding portion is disposed between two adjacent blades.

Description

BRIEF DESCRIPTION OF THE DRAWINGS

The invention will become more fully understood from the detailed description given herein below illustration only, and thus is not limitative of the present invention, and wherein:

FIG. 1 is a schematic diagram of the conventional fan;

FIG. 2 is a schematic diagram showing the airflow passing through the conventional hub and blade;

FIG. 3 is a schematic diagram of a fan according to a preferred embodiment of the invention;

FIG. 4 is a schematic diagram of a fan according to another preferred embodiment of the invention; and

FIG. 5 is a schematic diagram showing an airflow passing through the hub and blade of FIG. 4.

Claims

1. A fan comprising: an impeller, comprising: a hub having a top portion, a connection portion and at least one first airflow-guiding portion, wherein the top portion is connected to the connection portion, anda plurality of blades disposed around the connection portion, wherein the first airflow-guiding portion is disposed between adjacent two of the blades, disposed higher than a windward surface of the blades, located on an extending line extended from an end of the blade connecting with the hub or disposed higher than the extending line; anda motor disposed corresponding to the impeller for driving the impeller to rotate.

2. The fan of claim 1, wherein the first airflow-guiding portion is a recess or a protrusion.

3. The fan of claim 1, wherein the first airflow-guiding portion is contacted with adjacent two of the blades.

4. The fan of claim 1, wherein the first airflow-guiding portion has a shape of a polygon, a circle, an ellipse or a specific shape.

5. The fan of claim 1, wherein the first airflow-guiding portion is extended to the top portion, the connection portion or surfaces of the blades.

6. The fan of claim 1, wherein the direction of the first airflow-guiding portion depends on the direction of an airflow field provided by the blades.

7. The fan of claim 1, wherein the number of the first airflow-guiding portion is less than, equal to, or greater than the number of the blades.

8. The fan of claim 1, wherein the top portion, the connection portion and the first airflow-guiding portion are integrally formed as a single piece.

9. The fan of claim 1, wherein the hub further has at least one guiding angle located between the top portion and the connection portion, wherein the guiding angle is a right angle, an oblique angle, a round angle, an elliptic angle, or a ring-shaped structure.

10. The fan of claim 9, wherein the first airflow-guiding portion is extended to the guiding angle.

11. The fan of claim 9, wherein top ends of the blades are extended to a top end of the connection portion, the guiding angle or an edge of the top portion.

12. The fan of claim 1, further comprising: a second airflow-guiding portion disposed higher than a windward surface of the blades, or located on or higher than the extending line.

13. The fan of claim 12, wherein the second airflow-guiding portion is a recess or a protrusion.

14. The fan of claim 12, wherein the second airflow-guiding portion has a shape of a polygon, a circle, or an ellipse or a specific shape.

15. The fan of claim 12, wherein the second airflow-guiding portion is extended to pass through or contact with a wing surface or a front edge of the blade.

16. The fan of claim 12, wherein the second airflow-guiding portion is extended to the top portion, the connection portion, or surfaces of the blades.

17. An impeller comprising: a. hub having a top portion, a connection portion and at least one airflow-guiding portion, wherein the top portion is connected to the connection portion; anda plurality of blades disposed around the connection portion, wherein the airflow-guiding portion is disposed between adjacent two of the blades, disposed higher than a windward surface of the blades, located on an extending line extended from an end of the blade connecting with the hub or disposed higher than the extending line.

18. The impeller of claim 17, wherein the airflow-guiding portion is contacted with adjacent two of the blades.

19. The impeller of claim 17, wherein the airflow-guiding portion is extended to pass through or contact with a wing surface or a front edge of the blade.

20. The impeller of claim 17, wherein the airflow-guiding portion is extended to the top portion, the connection portion or surfaces of the blades.