Cooling device

Abstract

A piezoelectric fan includes a blade that is joined to a piezoelectric oscillator that bends in response to an application of a voltage, and the blade of the piezoelectric fan is arranged to swing in a space between neighboring heat dissipating fins of a heat sink. The formation of a hole in the blade increases the amplitude of the blade and also improves the sweep effect of sweeping high-temperature air in the vicinity of the wall of the heat dissipating fin, and thus, improves the cooling capability of the piezoelectric fan.

What is claimed is: 
     
         1 . A cooling device comprising:
 a piezoelectric fan including a piezoelectric oscillator arranged to bend in response to an application of a voltage and a blade that is connected to or provided integrally with the piezoelectric oscillator and that is arranged to swing by the piezoelectric oscillator; and   a heat sink including at least two heat dissipating fins; wherein   the blade has an elongated shape that extends from the piezoelectric oscillator;   the piezoelectric oscillator and the blade are arranged at a position that allows the blade to swing without coming into contact with the heat dissipating fins in a space between the neighboring heat dissipating fins; and   the blade includes at least one of a hole or a cut.   
     
     
         2 . The cooling device according to  claim 1 , wherein a weight is disposed at or in a vicinity of an end of the blade that is remote from the piezoelectric oscillator. 
     
     
         3 . The cooling device according to  claim 1 , wherein the blade has a bent shape such that a length of the blade is shortened in a longitudinal direction of the blade. 
     
     
         4 . The cooling device according to  claim 1 , wherein the piezoelectric oscillator is arranged so as to sandwich an end of the blade from both sides, and the piezoelectric oscillator and the blade define a bimorph oscillator. 
     
     
         5 . The cooling device according to  claim 1 , further comprising a fan arranged to generate a current of air that is directed to flow through the space between the heat dissipating fins. 
     
     
         6 . The cooling device according to  claim 1 , wherein the hole has an elongated shape extending along a longitudinal direction of the blade, and a dimension from a longitudinal-direction side of the blade to a side of the hole that is substantially parallel to the longitudinal-direction side is greater than a dimension of a gap between the blade and one of the heat dissipating fins.