Piezoelectric generator, sensor node, and method of manufacturing piezoelectric generator

Abstract

A piezoelectric generator includes: a base body; and at least one piezoelectric transducer disposed on the base body, and including a first electrode, a piezoelectric body, and a second electrode, wherein the piezoelectric transducer includes a support section fixed to the base body, and a vibrating section disposed apart from the base body, having one end connected to the support section and the other end set as a free end, and vibrating due to a vibration applied externally, and a distance between the other end of the vibrating section and the base body is larger than a distance between the one end of the vibrating section and the base body.

What is claimed is: 
     
         1 . A method of manufacturing a piezoelectric generator, comprising:
 forming a sacrificial layer by disposing a paste including a material to be thermally decomposed in a partial area on a base body layer using a droplet ejection process;   disposing a first electrode layer so as to straddle the base body layer and the sacrificial layer using a droplet ejection process;   disposing a piezoelectric body layer in paste form including piezoelectric particles on the first electrode layer using a droplet ejection process;   disposing a second electrode layer on the piezoelectric body layer using a droplet ejection process; and   firing the base body layer, the sacrificial layer, the first electrode layer, the piezoelectric body layer, and the second electrode layer.   
     
     
         2 . The method of manufacturing piezoelectric generator according to  claim 1 , further comprising:
 performing, prior to the firing the base body layer, an isostatic pressing process on the base body layer, the sacrificial layer, the first electrode layer, the piezoelectric body layer, and the second electrode layer,   wherein in the providing the base body layer, as the base body layer, there is prepared a ceramic sheet on which ceramics to be fired including the same component as a component of the piezoelectric body layer is disposed.   
     
     
         3 . The method of manufacturing a piezoelectric generator according to  claim 1 , wherein
 the base body layer is made of a material including a component the same as a component of the piezoelectric body layer.   
     
     
         4 . The method of manufacturing a piezoelectric generator according to  claim 1 , wherein
 a thermal contraction rate of the first electrode layer is lower than a thermal contraction rate of the piezoelectric body layer.   
     
     
         5 . The method of manufacturing a piezoelectric generator according to  claim 1 , wherein
 a thermal contraction rate of the second electrode layer is higher than a thermal contraction rate of the piezoelectric body layer.   
     
     
         6 . The piezoelectric generator manufactured by the method according to  claim 1 . 
     
     
         7 . A sensor node comprising:
 a sensor;   a circuit adapted to process data obtained by the sensor;   a communication system adapted to communicate the data obtained by the sensor; and   a power source adapted to drive the sensor, the communication system, and the circuit,   wherein the piezoelectric generator manufactured by the method according to  claim 1  is provided as the sensor and the power source.