Patent Application
20100267329
1. Technical Field
The present invention relates to fan-based heat dissipation mechanisms and, more particularly, to a return air blocking device for a fan-based heat dissipation mechanism having a plurality of fans, wherein a plurality of rotatable hinged plates are provided on outer sides of the fans and are lifted open or shut by virtue of the kinetic energy of airflow. Thus, when some of the fans fail to function, hot exhaust is prevented from returning to the heat dissipation mechanism and being detained therein, so as not to interfere with the design airflow.
2. Description of Related Art
In order to ensure highly reliable operation, information apparatuses such as industrial servers and computers are generally equipped with a fan-based mechanism including a fan configured for heat dissipation. When the fan works properly, heat dissipation is carried out as designed. However, the fan may fail unexpectedly whenever its service life comes to an end.
Hence, an information apparatus for industrial use typically has at least two cooling fans for backup purpose. Nevertheless, when one of the fans malfunctions (given a low chance of simultaneous breakdown of several fans), the airflow path in the apparatus will be adversely changed so that the intended heat dissipating effect is unattainable.
The aforesaid change of airflow path occurs because the malfunctioning fan is located at an air outlet important for heat dissipation. Once the fan stops operating, no hot air or exhaust will be discharged through the fan, thus turning the air outlet, which is usually adjacent to the other fan(s), into an air inlet for the immediately adjacent functioning fan(s). As a result, heat dissipation efficiency decreases significantly.
According to the present invention, a return air blocking device includes rotatable hinged plates installed at air outlets of cooling fans. When the fans are not in operation, the rotatable hinged plates are shut under the action of gravity. When the fans are actuated, air blown outward by the fans will rotate and lift the rotatable hinged plates up to allow passage of airflow.
Should one of the fans fail, the corresponding air outlet will be turned into an air inlet, and the corresponding rotatable hinged plate will be automatically shut by the incoming airflow in addition to gravity, thus blocking the now air inlet which might otherwise allow hot exhaust to return and interfere with heat dissipation.
Now that the factor causing the change of airflow path is eliminated, all the other functioning fans are allowed to maintain their intended operation, at deteriorated efficiency of heat dissipation, though. In so doing, hot exhaust is prevented from returning and being detained, so as not to interfere with the otherwise fluent heat-dissipating airflow.
The invention as well as a preferred mode of use, further objectives, and advantages thereof will be best understood by referring to the following detailed description of illustrative embodiments in conjunction with the accompanying drawings, wherein:
Referring to
When the fans in the chassis 1 work normally and blow out air, the rotatable hinged plates 13, 14, 15, 16, 17, 18 are rotated and lifted open by the kinetic energy of airflow driven by the fans, thus allowing hot exhaust to be discharged. When one of the fans, such as the one corresponding in position to the rotatable hinged plates 17, 18, fails, the rotatable hinged plates 17, 18 drop automatically and are thus shut due to gravity and absence of the airflow kinetic energy. In consequence, external air or hot exhaust discharged from the neighboring fan is prevented from being sucked into and detained in the chassis 1, which might otherwise result in obstruction of the heat-dissipating airflow.
Referring to
