PIEZOELECTRIC TRANSFORMER (BIMORPH) FOR ULTRASONIC DIAGNOSTIC CATHETER Russian patent published in 1997 - IPC

FIELD: ultrasonic diagnosis. SUBSTANCE: invention concerns piezoelectric transformers for medical one-dimension catheters and is aimed at increasing accuracy of piezoelectric transformer. Bushing of acoustic decoupling is made from a sealing agent filled with hollow microspheres to dense particle packing, and damper material is a polymer composition containing, wt. -%: tungsten powder with grain size 40-80 mcm, 60-65; fused corundum powder with grain size 400-1000 mcm, 20-25; hollow microspheres with sphere size 50-100 mcm, 3.7-3.9; epoxy resin, the balance. Composition is arranged in three layers. The first one is adjacent to piezoceramic plate and contains tungsten powder as filler (thickness h1). The second intermediate layer (h2) contains fused corundum powder, and third one (h3) is adjacent to end surface of acoustic decoupling bushing and contains hollow microspheres. H1:h2:h3 ratio is 1:1.5:2. EFFECT: increased accuracy. 1 dwg