| 摘要 |
PROBLEM TO BE SOLVED: To enhance the sensitivity by a human body about vibration sufficiently by adhering a piezoelectric element to both front and rear sides of an elastic plate and fixing a mass to one end of the elastic plate. SOLUTION: An elastic thin and long plate 3 that is made of a stainless steel, a spring steel, a phosphorus bronze or a toll steel has conductivity and high elasticity, the plate 3 is twisted (2) at the middle in the lengthwise direction. The twist angle is preferably within a range of 20-90 deg., and a piezoelectric element 4 is adhered to both front and rear sides of the elastic plate 3 that is extended horizontally or vertically around the middle part with the twist 2. The piezoelectric element is made of a proper material such as a binary system like a lead ziroconate titanate or a ternary system like a composite perovskite oxide Pb(Zr, Ti)O3 , or a lithium niobate (LiNbO3 ) single crystal. A mass 5 properly shaped to be a square tip, a rod tip, a trapezoidal tip, or a cone tip is fixed to one end of the elastic plate 3 by a proper means such as adhesion with a thermosetting adhesive like epoxy resin, screw fastening, or spot welding. |
