COOLING FAN WITH DAMPING STRUCTURE SUPPORTING A SHAFT OF THE COOLING FAN

• US 20070013247A1
• Filed: 03/08/2006
• Published: 01/18/2007
• Est. Priority Date: 07/13/2005
• Status: Abandoned Application

• Current Assignee: Foxconn Technology Co., Ltd.
• Original Assignee: Foxconn Technology Co., Ltd.
• Inventors: Yang, Chih-Hao, Hou, Chuen-Shu, Tung, Chao-Nien
• Application Number:
  US11/308,149
• Publication Number:
  US 20070013247A1
• Time in Patent Office: Days
• US Class Current: 310/90
• CPC Class Codes: F04D 25/062 Details of the bearings
• CPC Class Codes: F04D 29/0513 hydrostatic; hydrodynamic thrust bearings
• CPC Class Codes: F04D 29/057 hydrostatic; hydrodynamic
• CPC Class Codes: F04D 29/668 damping or preventing mechanical vibrations
• CPC Class Codes: H02K 2205/03 Machines characterised by thrust bearings
• CPC Class Codes: H02K 5/1675 radially supporting the rotary shaft at only one end of the rotor H02K5/1677 takes precedence

Abstract

A cooling fan includes a fan frame (10) having a central tube (12) defining a central hole (120) therein, a bearing (30) received in the central hole and a rotor (20) being rotatable with respect to the stator. The rotor includes a rotary shaft (24). A top end (240) of the shaft connects to a fan blade set. A free bottom end (242) of the shaft extends through the bearing into the central hole. A counter plate (40) made of high abrasion resistant material is located to face and supportively engage the free bottom end of the rotary shaft. A damping spring (70) exerts a force resiliently urging the counter plate against the free bottom end of the rotary shaft. The damping structure is capable of providing a cushion to a collision between the shaft and the bearing.

Claims

1. A cooling fan comprising:

a frame having a central tube defining a central hole therein;

a bearing received in the central hole of the central tube;

a rotor comprising a fan blade set and a rotary shaft extending downwardly from the fan blade set through the bearing into the central hole;

a counter plate made of high abrasion resistant material located to face and supportively engage a free end of the rotary shaft; and

a damping spring exerting a force resiliently urging the counter plate against the free end of the rotary shaft.

2. The cooling fan as claimed in claim 1, wherein the damping spring is made of one of following material:

macromolecule material, metal, metal alloy.

3. The cooling fan as claimed in claim 1, wherein the damping spring is an air spring.

4. The cooling fan as claimed in claim 3, wherein the air spring is one of a bellow-type air spring and a diaphragm-type air spring.

5. The cooling fan as claimed in claim 1, wherein the damping spring is a mechanical spring.

6. The cooling fan as claimed in claim 5, wherein the damping spring is selected from one of following springs:

coil spring, planar spring, conical spring, leaf spring.

7. The cooling fan as claimed in claim 1, wherein the free end forms a planar shaped bottom surface, the counter plate forms an arc-shaped upper surface abutting against the bottom surface of the shaft.

8. The cooling fan as claimed in claim 1, wherein an annular groove is defined in the shaft near the free end thereof, a locking washer is received in the groove to limit the movement of the shaft along an axial direction thereof.

9. A cooling fan comprising:

a base having a central tube defining a central hole therein;

a bearing received in the central hole;

a rotary shaft extending through the bearing into the central hole;

an elastic member arranged at a free end of the shaft;

a counter plate made of high abrasion resistant material located between the free end of the shaft and the elastic member;

a stator surrounding the central tube; and

a rotor connecting with an end of the rotary shaft opposite the free end thereof and having a magnetic interaction with the stator.

10. The cooling fan as claimed in claim 9, wherein the elastic member is one of a bellow-type air spring and a diaphragm-type air spring.

11. The cooling fan as claimed in claim 9, wherein the elastic member is selected from one of following springs:

coil spring, planar spring, conical spring, leaf spring.

12. The cooling fan as claimed in claim 9, wherein the free end forms a planar shaped bottom surface, the counter plate forms an arc-shaped outer surface abutting against the bottom surface of the shaft.

13. The cooling fan as claimed in claim 9, wherein an annular groove is defined in the shaft near the free end, a locking washer is received in the groove to limit the movement of the shaft along an axial direction thereof.

14. The cooling fan as claimed in claim 9, wherein the locking washer is located between the bottom end of the bearing and the central tube.

15. The cooling fan as claimed in claim 9, wherein elastic member is made of one of following material:

macromolecule material, metal, metal alloy.

16. A cooling fan comprising:

a frame having a central tube with a bottom opening;

a stator mounted on the central tube;

a bearing mounted in the central tube;

a rotor having a magnetic interaction with the stator, comprising a shaft fitting through the bearing, a hub having a central portion fixedly connected with a top end of the shaft, and a plurality of fan blades extending radailly outwardly from the hub;

a cap sealing the bottom opening of the frame;

an elastic member mounted on the cap; and

a counter plate mounted on the elastic member and supportively engaging with a bottom end of the shaft.

17. The cooling fan as claimed in claim 16, wherein the counter plate has an arc-shaped surface engaging with the bottom end of the shaft.

18. The cooling fan as claimed in claim 17, wherein the elastic member is an air spring.

19. The cooling fan as claimed in claim 17, wherein the elastic member is a mechanical spring.

20. The cooling fan as claimed in claim 19 further comprising a washer engaging a lower portion of the shaft and sandwiched between the bearing and the frame to limit an axial movement of the shaft.