VIBRATION SENSOR

PROBLEM TO BE SOLVED: To solve the following problems: there is the risk of breakage of a piezoelectric element, or separation of a diaphragm and the piezoelectric element, if a pickup section drops onto a ground surface or the like unexpectedly in transportation and installation before use, or receives an excessive impact. SOLUTION: A vibration sensor 20, including a pickup section 10 in which a weight 4 is enclosed in an air gap surrounded by a casing 1 and a diaphragm 2, and a piezoelectric element 3 is fitted to the diaphragm 2, and which picks up the vibration of the diaphragm 2 as a voltage from an output terminal 6 connected to the piezoelectric element 3, includes: an outer casing 12 for housing the pickup section 10; an elastic body 14 fitted in between the pickup portion 10 and the outer casing 12, and pressing members 11 and 13 for suppressing the elastic force of the elastic body 14 by pressing the elastic body 14. COPYRIGHT: (C)2011,JPO&INPIT