SU422470A1 - ELECTRODYNAMIC VIBRATOR - Google Patents

Description

one

The invention relates to vibration devices and can be applied in many industries.

In known vibrators, electromagnetics are more often used, and to ensure periodic oscillations, it is necessary to regulate the entire power supply current of the electromagnet, which complicates the power supply system and leads to instability of the parameters of the specified motion. In addition, the correction of movement in such vibrators by profiling the core is not sufficiently accurate and reliable.

The aim of the invention is to stabilize the parameters of the specified motion and to understand the structure of the vibrator.

The goal is achieved by the fact that the excitation driver in the proposed vibrator is located ferromagnetic; the cylinder at the end of the central ring of the magnetic system, the parameters of which are related by the relations:

/,,four; 0,1,, 9, (1)

where RI is the inner radius of the ring,

Rz is the outer radius

h is the ring height.

FIG. 1 shows the described vibration at the cut; in fig. 2 - the same, with a magnetic centering system.

The magnet 1, which is a permanent magnet or an electromagnet, has an annular cylinder 2 magnetized along its generator. The ferromagnetic cylinder 3 is mounted on the axis 4 near the end surface of the cylinder 2 where the magnetic field on the axis is maximal on the axis (the Z axis coincides with the axis of axial symmetry of magnet 1). Axis 4 is centered in sleeve 5. To reduce friction, you can use a pair of steel-fluorine plastic friction. The following coils are mounted on the axis: the driving roller 6, the measuring coil 7, the measuring coil 7. The spring 8 is fixed on the n axis on the body of the magnet 1.

The vibrator (Fig. 2) also contains a magnetic centering system 9. The tube 10 of a nonmagnetic electrically conductive material is fixed with the aid of an insulator And on a ferromagnetic core.

The vibrator works as follows.

If condition 1 is fulfilled, an alternating derivative is formed above the magnetized ring cylinder 2 (}. Ensuring the stable position of the ferromagnetic cluster over the pole, as shown in Fig. 1, or below the pole if the vibrator is rotated 180 ° relative to the Z axis.

The force returning the ferromagnetic body to the equilibrium position will be equal to Fz MdHzldz, where M is the induced (or constant) magnetic moment. If condition (1) is fulfilled, it is possible to choose parameters, Rz tl h so that dHz / dz const in the required range of values. Thus, the force Fz linearly depends on the magnetic moment of the ferromagnetic cylinder L1, and, consequently, the change in force (Afz) proportional to the current (/) in the driving coil 6 (i.e.). A voltage is applied to the coil 6, for example, from a periodic oscillator (NGPK). The nature of the movement is determined by the interaction of the variable moment M (f) with a constant derivative dHz / dzJr 0. Do not change the parameters of magnet 1 (i.e., when I const, dHz / dz const), you can change the rigidity of the magnetic suspension by changing the value ( and the sign) constant current current / in the coil, its coil 6. It is induced in the coil 7 emf. proportional to the speed specified by the motion coil 6. The signal taken from the coil 7 is fed to an oscilloscope as well as to an adder of an electrical feedback system (not shown) connected between coils 7 and 6 for motion correction. Thus, the current in the coil varies periodically so that the necessary law of change in speed is ensured. The ferromagnetic cylinder balanced in the direction of the z axis has an unstable equilibrium position in the layouts lying in the horizontal plane. A fluoroplastic sleeve with a steel axis or a magnetic system 9 with a nonmagnetic conductive tube 10 is used for centering. A variable magnetic field of the centering system 9 induces eddy currents in the tube 10, which interact with the magnetic field, pushing the tube away from the poles of the centering system, as a result of which the tube ferromagnetic cylinder centered in the direction of the z axis. When conducting low-temperature measurements in gamma-resonance spectroscopy, when the sample and the radiation detector are directly in liquid nitrogen (or helium), such a vibrator can also be placed in a liquid nitrogen medium (or helium) while maintaining its operability. The subject matter of the invention is an electrodynamic vibrator with a magnetic suspension, comprising an annular gap magnetic system, a ferromagnetic cylinder mounted on an axis above the annular pole of the magnetic system, an excitation coil and a measuring centering device, characterized in that, in order to simplify the design, the excitation coil is located on a ferromagnetic cylinder at the end of the central ring of the magnetic system, the dimensions of which are related by the relations: / ,, 4; O, K /, //., 0.9, where RI is the inner radius of the ring, 2 is the outer radius of the ring, / g is the height of the ring.

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