The method of reducing the impedance of the vibration table

Abstract

The invention discloses a new method of reducing vibrating table impedance, comprising: providing a metal ring used for a short circuit ring, wherein under a same temperature, the inner diameter of the metal ring is almost equal to the external diameter of the magnetic core of electric vibration test equipment, or the external diameter of the metal ring is almost equal to the inner diameter of the magnetic cylinder of the electric vibration test equipment; heating the metal ring until the inner diameter of the metal ring is extended to be greater than the external diameter of the magnetic core, rapidly sleeving the metal ring on the magnetic core, or heating the magnetic cylinder until the inner diameter of the magnetic cylinder is extended to be greater than the external diameter of the metal ring, and rapidly inserting the metal ring into the magnetic cylinder; and simultaneously cooling the metal ring sleeving the magnetic core and the magnetic core, allowing the metal ring and the magnetic core to form interference fit, or simultaneously cooling the metal ring inserted into the magnetic cylinder and the magnetic cylinder, allowing the magnetic cylinder and the metal ring to form interference fit. Accordingly, the method can greatly reduce equivalent impedance in an electric vibration test equipment magnetic circuit system, and optimize electric vibration test equipment work performance.

Description

technical field [0001] The invention relates to electrodynamic vibration test equipment, in particular to a method for reducing the impedance of a vibration table, which belongs to the field of machinery. Background technique [0002] The electrodynamic vibration test system is mainly composed of a movable system, a magnetic circuit system, an elastic support system, a guiding system, and a cooling device. The movable system is also called a moving coil, which is mainly composed of a driving coil wound on a skeleton with a working table. The working principle is that a DC current passes through the excitation coil on the magnetic circuit system to generate a constant magnetic field. The moving coil located in the constant magnetic field is affected by the alternating magnetic field generated by the alternating current supplied to the drive coil. According to the current-carrying conductor in the magnetic field Subject to Ampere's law of electromagnetic force, the moving coil...

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Problems solved by technology

However, electroless plating is often accompanied by side reactions, such as the production of cuprous oxide or copper particles, which cause the coating to be loose and rough, easy to fall off or oxidized, and then seriously affect the conductivity of the short-circuit ring

[0005] Another way in the prior art is to surfacing a layer of copper on the surface of the magnetic core or the magnetic cylinder to form a short-circuit ring, but due to the difference in the linear expansion coefficients of the copper, the magnetic core and the magnetic cylinder, cracks are likely to occur on the surface of the surfacing welding. Due to the high affinity between copper and oxygen, severe oxidation during surfacing will cause defects such as slag inclusions and pores, which will cause the formed short-circuit ring to have weak and uncontrollable electrical conductivity, which will cause side effects such as waveform distortion to the vibration test.

[0006] The inventor of this case also once proposed in the patent with the publication number CN101118198A that by opening a through hole on the plate, then curling the plate to form a cylinder, and then at the through hole, the butt edge of the plate after curling and the cylinder The upper and lower edges use gas shielded welding to weld the cylinder on the fixed surface to form a short-circuit ring, but because the electrical conductivity of the solder at the butt joint of the plates is often weaker than that of the main part of the plate, the electrical conductivity of the formed short-circuit ring is still not sufficient. To the extent expected by the industry

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