ULTRASONIC WAVE TRANSMITTER RECEIVER AND FLOW MEASURING INSTRUMENT FOR FLUID USING SAME

摘要

PROBLEM TO BE SOLVED: To improve the reliability of an ultrasonic wave transmitter receiver such that a case having a piezoelectric body fixed to a top wall internal surface and a terminal plate are joined together by electric welding by preventing the piezoelectric body fixed to the top wall internal surface of the case and the terminal plate from short-circuiting by preventing welding dust from scattering. SOLUTION: A flange 9 extending outward from a lower open end of the conductive cap-shaped case 6 is formed in one body, the outer periphery of the conductive terminal plate 10 is electrically welded, and then an airtight space 11 is formed in the case 6. A welding projection 17 is annularly provided on a top surface 16 nearby the outer periphery of the terminal plate 10 and a welding dust diffusion preventive projection 18 as a welding dust diffusion preventing means is annularly provided inside it. The case 6 and the terminal plate 10 are electrically welded through the welding projection 17, but welding dust is never diffused into the case 6 in this case because of the welding dust diffusion preventing projection 18. COPYRIGHT: (C)2006,JPO&NCIPI