Blower exhaust backflow damper

• US 7,416,481 B2
• Filed: 03/06/2006
• Issued: 08/26/2008
• Est. Priority Date: 03/06/2006
• Status: Active Grant

• Current Assignee: Lenovo International Limited (Lenovo Group Ltd.)
• Original Assignee: International Business Machines Corporation
• Inventors: Jensen, David J., Lewis, Seth D., Henry, Matthew S., Baker, Bruce E.
• Primary Examiner(s): McAllister; Steven B.
• Assistant Examiner(s): OREILLY, PATRICK F
• Application Number:
  US11/368,778
• Publication Number:
  US 20070207723A1
• Time in Patent Office: 904 Days
• Field of Search: 454/184, 454/227, 454/229, 454/259, 454/353, 454/359, 361/687, 361/695
• US Class Current: 454/184
• CPC Class Codes: F04D 25/14 and having shutters, e.g. automatically closed when not in use
• CPC Class Codes: F04D 29/663 Sound attenuation
• CPC Class Codes: F24F 7/007 with forced flow using ducting systems F24F7/06
• CPC Class Codes: H05K 7/20172 Fan mounting or fan specifications

Abstract

A system, method, and apparatus for preventing exhaust backflow into a blower are disclosed. Embodiments may include a blower system with an invertible blower chassis having a blower exhaust to direct airflow from the blower chassis at an airflow angle. The system may also include a backflow damper frame attached to the blower chassis and positioned to receive airflow from the blower chassis and one or more vertical damper vanes rotatably attached to the backflow damper frame. Each damper vane may freely rotate between a first, closed position and a second, open position. The damper vanes may block airflow into the blower exhaust when in the closed position and may freely rotate to a position where the damper vanes are substantially parallel to the airflow from the blower exhaust. The damper vanes may each include a vane pin to rotatably attach to frame holes of the backflow damper frame.

Claims

1. A blower system, the system comprising:

an invertible blower chassis having a blower intake fan having a rotational axis to draw air into the invertible blower chassis substantially along the rotational axis of the blower intake fan and having a blower exhaust substantially perpendicular to the blower intake fan rotational axis to direct an airflow from a side of the blower chassis at an airflow angle that is between an axis perpendicular to the chassis side and an axis parallel to the chassis side, the blower chassis being adapted to be used with both a first side and a second, opposite side being substantially perpendicular to a vertical axis aligned with a gravitational force, wherein the airflow angle is at an acute non-zero angle from the axis perpendicular to the chassis side and wherein further the airflow angle is substantially large such that the airflow angle is non-perpendicular to the chassis side;

a backflow damper frame attached to the blower chassis and positioned to receive airflow from the blower chassis at the acute non-zero airflow angle;

one or more damper vanes rotatably attached to the backflow damper frame, each damper vane having a vane body with a long axis, wherein the long axes of the one or more vane bodies are substantially parallel to the chassis vertical axis, and wherein the one or more damper vanes are adapted to freely rotate between a first, closed position and a second, open position; and

wherein the one or more damper vanes block airflow into the blower exhaust when the one or more damper vanes are in the closed position, and wherein further the one or more damper vanes freely rotate to a position where the one or more vane bodies are substantially parallel to the airflow from the blower exhaust at the acute non-zero airflow angle.

2. The system of claim 1, wherein the backflow damper frame further comprises a pair of opposing frame holes for each of the one or more damper vanes.

3. The system of claim 2, wherein at least one of each pair of opposing frame holes comprises a notch to restrain a keyed end of a damper vane.

4. The system of claim 1, wherein the one or more damper vanes comprise four damper vanes.

5. The system of claim 1, wherein the one or more damper vanes comprise two or more damper vanes.

6. The system of claim 1, wherein the one or more damper vanes are constrained to rotate within approximately ninety (90) degrees or less from the closed position.

7. The system of claim 1, wherein the one or more damper vanes each further comprise a vane pin to rotatably attach to frame holes of the backflow damper frame.

8. The system of claim 7, wherein at least one vane pin for each damper vane comprises a keyed end.

9. A backflow damper apparatus for a blower, comprising:

a backflow damper frame having a perimeter defining an airflow area, the airflow area of the backflow damper frame, when installed in a blower, being centered geometrically about an axis substantially perpendicular to a rotational axis of a blower intake fan of the blower that draws in air substantially along the rotational axis of the blower intake fan, the backflow damper frame being adapted to receive and pass an angled airflow from a blower exhaust through the airflow area where the blower exhaust airflow flows substantially at an airflow angle that is between an axis perpendicular to the airflow area and an axis parallel to the airflow area, wherein the airflow angle is at a non-zero acute angle from the axis perpendicular to the airflow area and wherein further the airflow angle is substantially large such that the airflow angle is non-perpendicular to the airflow area;

one or more damper vanes rotatably attached to the perimeter of the backflow damper frame, each damper vane having a vane body with a long axis, wherein the long axes of the one or more vane bodies are adapted to be vertically oriented when the backflow damper is attached to the blower, and wherein the one or more damper vanes are adapted to freely rotate between a first, closed position and a second, open position; and

wherein the one or more damper vanes block airflow into the blower exhaust when the one or more damper vanes are in the closed position, and wherein further the one or more damper vanes rotate to a position where the one or more vane bodies are substantially parallel to the airflow at the non-zero acute airflow angle from the blower exhaust during blower operation.

10. The apparatus of claim 9, wherein the backflow damper frame further comprises a pair of opposing frame holes for each of the one or more damper vanes.

11. The apparatus of claim 10, wherein at least one of each pair of opposing frame holes comprises a notch to restrain a keyed end of a damper vane.

12. The apparatus of claim 9, wherein the one or more damper vanes comprise four or more damper vanes.

13. The apparatus of claim 9, wherein the one or more damper vanes are constrained to rotate within approximately ninety (90) degrees or less from the closed position.

14. The apparatus of claim 9, wherein the one or more damper vanes each further comprise a vane pin to rotatably attach to frame holes of the backflow damper frame.

15. The apparatus of claim 14, wherein at least one vane pin for each damper vane comprises a keyed end.