ELEKTRO-MECHANISCHE OVERDRAGER VOOR EEN AKOESTISCH TELEMETRIE-SYSTEEM.

摘要

An improved electromechanical transducer is provided for use in an acoustic telemetry system. The transducer of this invention comprises a stack of ferroelectric ceramic disks interleaved with a plurality of spaced electrodes which are used to electrically pole the ceramic disks. The ceramic stack is housed in a metal tubular drill collar segment. Thick metal spacer plate are selectively sandwiched between electrodes in order to promote thermal cooling of the ceramic stack. In accordance with an important feature of this invention, the thick metal spacer plates are comprised of a material (such as copper alloys, aluminum alloys or the like) which is softer than the relatively hard, brittle ceramic disks thus reducing the stresses upon the disks when the assembly is subjected to bending, torsion and the like, and thereby minimizing the risk of structural failure of the disks when in operation within a downhole acoustic signal generator.