PIEZO-ELECTRIC TRANSFORMER Russian patent published in 2007 - IPC H04R17/00 

FIELD: ultrasound engineering, possible use in technological processes, for example during ultrasound processing of materials.

SUBSTANCE: transformer contains a packet of flat piezo-ceramic rings 1 with current-feeding washers 2. The packet is positioned between front and back cover plates 5 and 6, coupled by tie rod 7 by means of threaded connections 8 and 9. Diameter of smooth part d of rod 7 is less than diameters D₁ and D₂ of threaded connections 8 and 9. Between strings of thread, made in apertures of cover plates 5 and 6, and thread, made on tie rod 7, and also in the gap between surface of back cover plate 6 and smooth part of rod 7, a layer of soldering alloy is located. Between rod 7 and apertures of piezo-ceramic rings 1 and current-conductive washers 2 a bushing 11 made of electro-insulating material is mounted. Ratio of distance L₁ from the middle of length of threaded part until the end of rod 7, held in front cover plate 5 until the end of front cover plate, to distance L₂ from the middle of length of this part until the end of rod 7, held in aperture of back cover plate 6, equals 0,3-0,6.

EFFECT: reduced internal resistances and increased reliability.

7 cl, 1 dwg