Patent ID: 7067960
Filing Date: 2006-06-27
Classification: F02M,H01L

Abstract:
1. A piezoelectric device for an injector built in an injector and generating driving force of said injector, characterized in that: said piezoelectric device is fabricated by alternately laminating a plurality of piezoelectric layers expanding and contracting in proportion to an applied voltage and a plurality of internal electrode layers for supplying the applied voltage; at least a part or the whole of a sectional shape of said piezoelectric device crossing at right angles the laminating direction is arcuate; and said piezoelectric device is accommodated in a circular cylindrical accommodation space; wherein a proximity ratio expressed by (B/A)×100 (%), where A is a length of the whole circumference of a circumscribed circle of said piezoelectric device and B is the sum of length of circumferential portions having a distance of 0.2 mm or below between said circumscribed circle and said piezoelectric device, is larger than 17%.