Fan assembly

Abstract

A fan assembly includes a rack, a shield, and a fan. The rack defines a first vent opening and a second vent opening aligned with the first vent opening. The shield is mounted in the rack and aligned with the first vent opening. The shield defines a frame opening corresponding to the first vent opening. A plurality of shielding pieces are pivotally mounted in the frame opening, and rotate to shield the frame opening because of gravity. The shield includes a plurality of guarding bars to guard the plurality of shielding pieces from being damaged. The fan is mounted in the rack and aligned with the second vent opening and the shield. The fan generates air flow flowing through an air passage between each adjacent two of the plurality of shielding pieces, and the plurality of shielding pieces are rotated by the air flow.

What is claimed is: 
     
         1 . A fan assembly, comprising:
 a rack defining a first vent opening and a second vent opening aligned with the first vent opening,   a shield mounted in the rack and aligned with the first vent opening, the shield defining a frame opening corresponding to the first vent opening, a plurality of shielding pieces pivotally mounted on the frame opening, the plurality of shielding pieces are rotatable to a closed position, to shield the frame opening, due to the force of gravity, the shield comprising a plurality of guarding bars, and the plurality of guarding bars configured to prevent the plurality of shielding pieces from being damaged; and   a fan mounted in the rack and aligned with the second vent opening and the shield; the fan is configured to generate airflow flowing through an air passage between each adjacent two of the plurality of shielding pieces, and the plurality of shielding pieces are configured to be rotated by the airflow.   
     
     
         2 . The fan assembly of  claim 1 , wherein the shield comprises a frame, the frame comprises a first side and a second side, the second side faces to the fan, and the first side faces back to the fan, and the frame opening extends through the first side and the second side. 
     
     
         3 . The fan assembly of  claim 2 , wherein the plurality of shielding pieces are pivotally mounted on the second side, and the plurality of guarding bars are mounted on the first side. 
     
     
         4 . The fan assembly of  claim 3 , wherein each of the plurality of shielding pieces comprises a rotating portion and a free portion, opposite ends of the rotating portion form a pair of pivot shafts, and the frame defines a plurality of pivot holes for the pivot shafts of the plurality of shielding pieces being pivotally mounted therein. 
     
     
         5 . The fan assembly of  claim 4 , wherein each of the plurality of shielding pieces comprises a first side face and a second side face, the first side face faces to the first vent opening, the second side face faces to the fan; and between each adjacent two shielding pieces, a second side face of the free portion of one of the two shielding pieces is located on a first side face of the rotating portion of another one of the two shielding pieces. 
     
     
         6 . The fan assembly of  claim 3 , wherein a plurality of blocking bars is located on the first side and adjacent to opposite edges of the frame opening, and each of the plurality of shielding pieces is configured to rotate until each of the plurality of shielding pieces abuts corresponding blocking bar. 
     
     
         7 . The fan assembly of  claim 1 , wherein the fan comprises a side plate, an elastic piece is located on the side plate, a protrusion is located on the elastic piece, the rack defines a mounting hole, and the elastic piece is configured to be elastically bent by the rack such that the protrusion is mounted in the mounting hole. 
     
     
         8 . The fan assembly of  claim 1 , wherein the rack defines a notch above the first vent opening, the shield comprises a lock; the lock comprises a connection piece, a bent piece, and a handle; the connection piece is connected to the shield; the bent piece is perpendicularly connected to a top portion of the connection piece; the handle is perpendicularly connected to the bent piece; a tab is located on a connection portion between the bent piece and the connection piece, the bent piece is configured to be elastically bent by the rack such that the tab is mounted in the notch; and the handle is configured to be pulled to bent the bent piece and to move the tab out of the notch. 
     
     
         9 . The fan assembly of  claim 1 , wherein the rack comprises a limiting piece separating the shield from the fan. 
     
     
         10 . The fan assembly of  claim 9 , wherein a distance between the second vent opening and the limiting piece is greater than that between the first vent opening and the limiting piece. 
     
     
         11 . A fan assembly, comprising:
 a rack comprising a first side wall and a second side wall, the first side wall defining a first vent opening, the second side wall defining a second vent opening aligned with the first vent opening;   a fan mounted between the first side wall and the second side wall, the fan aligned with the second vent opening;   a shield mounted between the fan and the first side wall, the shield defining a frame opening aligned with the fan and the first vent opening, a plurality of shielding pieces pivotally mounted in the frame opening, the plurality of shielding pieces are rotatable to a closed position, to shield the frame opening, due to the force of gravity, the shield comprising a plurality of guarding bars, and the plurality of guarding bars configured to prevent the plurality of shielding pieces from being damaged;   wherein the fan is configured to blow air towards the plurality of shielding pieces such that the plurality of shielding pieces are configured to be rotated to uncover the frame opening.   
     
     
         12 . The fan assembly of  claim 11 , wherein the shield comprises a frame, the frame comprises a first side and a second side, the second side faces to the fan, the first side faces back to the fan, and the frame opening extends through the first side and the second side. 
     
     
         13 . The fan assembly of  claim 12 , wherein the plurality of shielding pieces are pivotally mounted on the second side, and the plurality of guarding bars are mounted on the first side. 
     
     
         14 . The fan assembly of  claim 13 , wherein each of the plurality of shielding pieces comprises a rotating portion and a free portion, opposite ends of the rotating portion form a pair of pivot shafts, and the frame defines a plurality of pivot holes for the pivot shafts of the plurality of shielding pieces being pivotally mounted therein. 
     
     
         15 . The fan assembly of  claim 14 , wherein each of the plurality of shielding pieces comprises a first side face and a second side face, the first side face faces to the first vent opening, the second side face faces to the fan; and between each adjacent two shielding pieces, a second side face of the free portion of one of the two shielding pieces is located on a first side face of the rotating portion of another one of the two shielding pieces. 
     
     
         16 . The fan assembly of  claim 13 , wherein a plurality of blocking bars is located on the first side and adjacent to opposite edges of the frame opening, and each of the plurality of shielding pieces is configured to rotate until each of the plurality of shielding pieces abuts corresponding blocking bar. 
     
     
         17 . The fan assembly of  claim 11 , wherein the fan comprises a side plate, an elastic piece is located on the side plate, a protrusion is located on the elastic piece, the rack defines a mounting hole, and the elastic piece is configure to be elastically bent by the rack such that the protrusion is mounted in the mounting hole. 
     
     
         18 . The fan assembly of  claim 11 , wherein the first side wall defines a notch above the first vent opening, the shield comprises a lock; the lock comprises a connection piece, a bent piece, and a handle; the connection piece is connected to the shield; the bent piece is perpendicularly connected to a top portion of the connection piece; the handle is perpendicularly connected to the bent piece; a tab is located on a connection portion between the bent piece and the connection piece, the bent piece is configured to be elastically bent by the rack such that the tab is mounted in the notch; and the handle is configured to be pulled to bent the bent piece and to move the tab out of the notch. 
     
     
         19 . The fan assembly of  claim 11 , wherein the rack comprises a limiting piece separating the shield from the fan. 
     
     
         20 . The fan assembly of  claim 19 , wherein a distance between the second side wall and the limiting piece is larger than that between the first side wall and the limiting piece.