Fan with self closing blades

• US 6,386,826 B1
• Filed: 09/22/2000
• Issued: 05/14/2002
• Est. Priority Date: 09/23/1999
• Status: Expired due to Term

• Current Assignee: X Corp. (f/k/a Twitter, Inc.) (X Holdings Corp.)
• Original Assignee: International Business Machines Corporation
• Inventors: Jacob, Francois
• Primary Examiner(s): Lopez, F. Daniel
• Assistant Examiner(s): EDGAR, RICHARD A
• Application Number:
  US09/668,259
• Time in Patent Office: 599 Days
• Field of Search: 415/60, 415/61, 415/33, 415/35, 415/42, 415/125, 415/141, 415/146, 415/147
• US Class Current: 415/125
• CPC Class Codes: F04D 29/364 The blades having only a predetermined number of possible positions

Abstract

A fan system to be mounted over an opening including a plurality of pivoting blades fixed on a free wheeling element and a motor driven element wherein, in operation, when the fan is operating the motor driven element pivots the blades to a blowing position allowing air flow through the opening, and when the fan is not operating a resilient member pivots the blades to a closed position preventing air flow through the opening.

Claims

1. A fan system comprising at least one fan to be mounted over an opening comprising:

a central rotating element (30);

a plurality of pivoting blades (20) fixed on the central rotating element (30);

means for automatically closing the opening with the surface of the blades when the fan is stopped comprising means for pivoting each blade (20) around an axis fixed on said central rotating element (30) from an open to a closed position; and

means for automatically placing blades in a blowing position when the fan is running comprising means for pivoting each blade (20) around an axis fixed on said central rotating element (30) from a closed position to a blowing position.

2. The fan system according to claim 1 further comprising:

a motor driven element (40) comprising means for rotating said blades and for pivoting said blades from the closed to the blowing position.

3. The fan system according to claim 2, wherein said means for rotating said blades are first stops fixed on said motor driven element (40).

4. The fan system according to claim 1 wherein said central rotating element (30) is a free wheeling element and wherein said means for pivoting each blade (20) around an axis comprises:

means for positioning each blade in the closed position;

means for positioning each blade in the open position;

means for pivoting each blade from the blowing to the closed position.

5. The fan system according to claim 4, wherein said means for positioning each blade in the open position is a second stop.

6. The fan system according to claim 4, wherein said means for positioning each blade in the closed position is a third stop.

7. The fan system according to claim 4, wherein said means for pivoting each blade from the blowing to the close position is a spring.

8. The fan system of claim 1, wherein there are a plurality of fans.

9. A fan system comprising at least one fan to be mounted over an opening comprising:

a motor driven element (40) having first stops (70);

a free wheeling element (30);

a plurality of pivoting blades (20) fixed on the free wheeling element (30); and

resilient members (10) fixed on the free wheeling element (30);

wherein, in operation, when the fan is operating and motor driven element (40) is engaged, first stops (70) push said pivoting blades to a first, blowing position and when the fan is not operating, said resilient members (10) push said pivoting blades (20) to a second, closed position.

10. The fan system of claim 9 further comprising second stops (80) fixed on the free wheeling element (30) which limit the pivoting movement of each pivotable blade (20) in the first, blowing position.

11. The fan system of claim 10 further comprising third stops (60) fixed on the free wheeling element (30) which limit the pivoting movement of each pivotable blade (20) in the second, closed position.

12. The fan system of claim 9 wherein the resilient members (10) are springs.

13. The fan system of claim 9 wherein there are a plurality of fans.

14. The fan system of claim 9 wherein motor driven element (40) and free wheeling element (30) are rotatable about the same axis of rotation.