SU1507352A1 - Ultrasonic instrument for acting on biological tissue - Google Patents

Abstract

The invention relates to an ultrasound medical technique and can be used in urology for the destruction of ureteral stones, in bronchotomy for ultrasound treatment, in vascular surgery and other areas of medicine. The aim of the invention is to increase the efficiency of ultrasonic tissue treatment by increasing the coefficient of oscillation conversion. For this purpose, the tool, consisting of a half-wave transducer of piezoactive material half-wave hub and a flexible waveguide, the waveguide length is selected on the condition that L _B / L ^_N. √E _N ρ _B / E _B ρ _N = N + 1/2, where L _B is the waveguide length

L _N - length of the transducer

E _N , ρ _N - Young's modulus and density of the converter material

E _B , ρ _B - Young's modulus and density of the waveguide material

N is an integer between 10≤N≤30, and the ratio of mechanical impedances of the converter and the waveguide is within 10 ² ≤Z _N / Z _B ≤10 ⁴ , where Z _N = S _N √ ρ _N E _N is impedance converter

Z _B = S _B √ ρ _B E _B - waveguide impedance

S _N and S _B are the cross-sectional areas of the transducer and the waveguide, respectively. 1 il.

Description

3150

occasion 3 with working chic D intended for carrying out ultrasonic action on biological tissue.

The tool works as follows.

When an electrical signal is applied to transducer 1, longitudinal mechanical oscillations are excited in it, which are amplified by adjusting the entire instrument to resonance. Typically, the length of ultrasonic instruments consisting of a transducer, a concentrator and a waveguide is equal to an integer number of half-waves. In the proposed device, the length of the waveguide Lg is equal to half the integer number of half-waves of longitudinal vibrations The conditions Zn / Z6 10 -10 and p 10-30, where 7, „and Z are the mechanical impedances of the piezotransducer and the waveguide, respectively, are not met, the amplitude of the oscillations of the tip 4 will be small due to the fact that the exciting part of the instrument has a significant acoustic load. To avoid this situation, it is necessary to fulfill the last two conditions. These characteristics define the range of permissible parameters at which the oscillation conversion factor of the entire tool increases. In a flexible waveguide, longitudinal-flexural oscillations of a longitudinal type are excited, which cause the working tip to perform longitudinal oscillations.

The significant length of the waveguide, its Q flexibility and small transverse dimensions allow atraumatic penetration into the

hard-to-reach places ort and coBepuiafb required ultrasonic effect, for example, destruction of ureteral stones.

Claims (1)

Invention Formula Ultrasonic instrument for affecting biological tissue, containing a half-wave transducer made of piezo-active material, connected through a half-wave concentrator with a flexible waveguide having a working tip, characterized in that, in order to increase the efficiency of ultrasonic tissue treatment by increasing the oscillation conversion factor, the waveguide length is chosen from  n + 1/2, where L is the waveguide length; I n is the length of the transducer; Е j, j) is the Young's modulus and density of the transducer material; Ej, R. — Young's modulus and density of the waveguide material; n - integer enclosed in within 10 to 30, the ratio of the mechanical impedances of the converter and the waveguide is enclosed within 102 Zn / Zg 10 “Ur Е - converter impedance; waveguide impedance; the cross-sectional area of the transducer and the waveguide, respectively. Where Z. S Editor A.Lezhnina Compiled by U.Ilinykh Tehred M.Hodanich Order 5479/7 Circulation 6AZ VNIIPI State Committee for Inventions and Discoveries at the State Committee on Science and Technology of the USSR 113035, Moscow, Zh-35, Raushsk nab. 4/5 Production and Publishing Combine Patent, Uzhgorod, st. Gagarin, 101 Proctor K.Samborska Subscription