| 摘要 |
<p>PURPOSE:To prevent electronic parts from being broken down by dust by stopping up exhaust holes with a filter when a blower is operated or by automatic return of tongues when the blower is stopped and thereby preventing intrusion of dust. CONSTITUTION:Air sucked by a blower through suction holes is filtered by a filter and exchanges heat with heated parts, such as electronic parts, in a box. In this time, the tongues 15 of an opening/closing member 11 are turned upward by wind pressure to open exhaust holes 13 and the air heat-exchanged with the heated parts is exhausted to the outside through the exhaust holes 13. When the blower is stopped, the tongues 15 of the opening/closing member 11 stop up the exhaust holes 13 to prevent dust from intruding into the box. The filter of the suction holes 4 thus prevents dust in the outside air from intruding to always keep a cooling wind clean. Because the inside of the box 2 is kept at positive pressure, intrusion of dust through the exhaust holes 13 is prevented by exhausting a wind through the exhaust holes 13 after cooling.</p> |
