SU1609513A1 - Ultrasonic radiator - Google Patents

Abstract

The invention relates to ultrasound technology. The purpose of the invention is to increase the radiation efficiency and reduce the size of the radiator. The waveguide is made in the form of coaxially mounted cylindrical sections 1. Each of the sections is made in the form of a magnetostrictive flat spiral. The waveguide is provided with an excitation winding 2. Neighboring sections of the waveguide have opposite magnetostriction signs and are connected to each other through disks 3 with perforations in the form of petals. The length of the petals is a multiple of half the wavelength of bending vibrations. Petals of adjacent disks are shifted relative to each other along a helical line by an angle of 2ϕ / KN, where K is the number of disks

N is the number of lobes of the disk. The waveguide sections 1 and the disks 3 are located between the face plates 5, which are mounted with a stud 6 of a permanently magnetized material. The length of each of the sections 1 is equal to half the wavelength of the longitudinal vibrations. The surfaces of the disks 3 are provided with identical annular coaxial protrusions 7, the inner diameter of which is equal to the outer diameter of the waveguide. The waveguide is closed by a housing 8, the outer diameter of which is smaller than the outer diameter of the discs 3. The face plates close the open ends of the housing 8. As current flows through the winding 2, the diameters of the adjacent sections of the waveguide increase and decrease accordingly, depending on their sign of magnetostriction. Waveguide oscillations are transmitted to the disks 3. 4 Il.

Description

(rig. 1

The invention relates to sound engineering and can be used in mechanical engineering, electronic, chemical and other industries to intensify the process of sounding media during washing, cleaning, dispersing, etc.

The aim of the invention is to increase the radiation efficiency and reduce the size of the radiator.

FIG. 1 shows a radiator, a longitudinal section; in fig. 2 - diagrams of the longitudinal oscillations of the waveguide; in fig. 3 is a section A-A in FIG. one; in fig. 4 - diagram of bending vibrations of the disks. ; The ultrasonic emitter contains a waveguide in the form of coaxially mounted cycles | indric sections 1. Each section is made in the form of a magnetostrictive strip of a spiral. The waveguide is provided with excitation winding 2. The adjacent sections of the waveguide have opposite signs of magnetostriction and are connected to each other through disks 3 with perforations in the form of petals 4. The length of the petals is a multiple of half the wavelength of the flexural vibrations. Petals of 4 adjacent disks are shifted relative to each other along a helix by an angle, where k is the number of disks; n is the number of l disk sands. The waveguide sections 1 and the discs 3 | are located between the end plates 5, which are made up of a pin 6 of a permanently magnetized material. 1, the length of each section 1 is equal to half the wavelength of the longitudinal oscillations. The surfaces of the disks 3 are provided with identical annular coaxial protrusions 7, the inner diameter of which is equal to the outer diameter of the waveguide. The waveguide is closed by a casing 8, the outer diameter of which is smaller than the outer diameter of the discs 3. The end plates cover the open ends of the casing 8. Distance rings 9 are placed between the projections of the adjacent discs.

The device works as follows.

By making the stud 6 in the form of a permanent magnet in the internal volume of the radiator, a constant magnetic field of biasing of the water wave sections 1 is created. Neighboring sections are made of materials with an equal in magnitude, but opposite in sign, magnetostrictive elongation, for example, from nickel (K - -40) and alphene, 10-14 (K - +40), where

And to

K – 10 μm. . In this case, the pair

materials are characterized by almost identical propagation rates of the longitudinal ultrasonic wave: VNI

 4780 m / s, Vio-14 4750 m / s. The dispersion of a constant magnetic field in the emitter is minimal, since it is screened by a split casing 8 and end plates 5, made of a ferromagnetic material. An alternating magnetic field is created by passing an ultrasonic frequency (not shown) electric current across the excitation winding 2 from the generator. The creation of a constant bias field in the emitter allows it to simplify the scheme of the ultrasonic atom gene (the constant current component is excluded), reducing its size and weight.

15 When a constant and alternating magnetic field is applied to the magnetostriction materials of the waveguide section 1 (in one half-cycle of alternating electric current), an instantaneous decrease in length and a corresponding increase in diameter and a corresponding increase in length and decrease in the diameter of the waveguide sections occur, depending on the sign of magnetostriction . These alternate changes

25 occurs at a frequency of alternating current and is transmitted to the disks 3. Thus, the resonant longitudinal oscillations of the waveguide sections of the half wavelength

are transformed into resonant bending vibrations of disks with lobes 4.

At the same time, due to the direct contact of the sections 1 of the waveguide with the disks 3, a high efficiency of transformation of longitudinal vibrations into bending is achieved, since

35, the longitudinal and transverse displacements of the volume of the material of the waveguide sections 1 and the corresponding bend of the gaplessly connected to the sections 1 of the disc 3 are simultaneously involved in the transmission of vibrations. Equality

40 and the opposite sign of the magnetostrictions of the adjacent sections of the waveguide determines the invariance of the longitudinal length of the radiator, i.e. constant preliminary tightening of the radiator elements on the stud and, consequently, a constant resonant frequency of oscillations. The waveguide sections are used only in pairs (alternately in pairs), since an unpaired installation leads to a change in the longitudinal length of the radiator.

50 and care of the resonant frequency of oscillations.

Perforation in the form of petals reduces the rigidity of the discs and, consequently, increases the amplitude of the bending vibrations. The rotation of the petals in the radiator body along a helix facilitates the creation of turbulent microflows and microvortices in the processed liquid. In this case, stagnant zones near the radiator casing will be eliminated, improving the mixing of the fluid and, for example, cleaning the channels. The widening of waveguides from a tape rolled up into a flat spiral simplifies the selection of the workpiece and allows you to get an analogue of a magnetostrictor, usually assembled from electrical insulated, for example, by oxidizing the surface of thin plates. Such a design reduces heat losses due to Foucault currents, and therefore, the manufacture of a waveguide from a tape coiled into a flat helix is preferable.

The emitter according to the invention can be effectively used for ultrasonic cleaning of channels and pipelines, including from relatively small to large sections, for example, from 30 to 300 mm. for initiating intense cavitation in cleaning baths, as well as for dispersing and moving media components, etc.

Claims (1)

Invention Formula An ultrasonic emitter containing a waveguide in the form of interconnected coaxially mounted cylindrical sections, an active element, a housing, perforated disks arranged parallel to each other and connected with a waveguide, the length of each section of which is equal to half the wavelength of the longitudinal oscillations, characterized in that, in order to increase efficiency and reduce the size, the cylindrical sections of the waveguide are connected to each other through disks and are located between the face plates, studded magnetized material, the surfaces of the disks are equipped with identical annular coaxial protrusions, the inner diameter of which is equal to the outer diameter of the waveguide, each of which sections is made in the form of magnetostriction and the perforations of the disks are petal-shaped, a multiple of half the wavelength of flexural vibrations, the petals of adjacent disks are shifted relative to each other along a helix by an angle, 2Jficn where k is the number of disks, n is the number of disk petals, adjacent sections of the waveguide have opposite signs of magnetostriction, the outer diameter of the casing is smaller than the outer diameter of the disks, and the face plates cover the open ends of the casing - / Fig 2