| 摘要 |
<p>A thin metal diaphragm on which a disc of piezoelectrical material is placed forms the bottom of the case of an ultrasonic transducer. The case is a conductor of electricity, and a second electrode is fixed on the second face of a conducting wire. The transducer includes also: a first flange fixed to the upper part of the case; a coaxial cable which ends at a second flange for attachment to the first; a first spindle fixed to the upper end of the first conducting wire, which is acted on by a mechanism tending to lift it from the case, the spindle having a concave or convex contact face at its emtremity; a second spindle at the lower end of the central conductor of the coaxial cable, projecting into the second flange, and having a contact face which is complementary to that of the first spindle, and means of ensuring continuous electrical flow between the case and the peripheral conductor of the coaxial cable; and a joint ring between the two flanges. An ultrasonic detector enclosed in a sealed case for immersion in the liq. sodium cooling a fast breeder reactor core. The design ensures that a connection between the case itself and the connector of the transducer can be assembled and dismantled without the inconvenience and difficulties associated with existing equipment. The instrument is very well suited for working in adverse conditions of temperature and pressure, and elivers an acoustic or visual detection signal.</p> |
