Three-freedom parallel vibration isolating platform with quasi-zero stiffness characteristic

Abstract

The invention discloses a three-freedom parallel vibration isolating platform with quasi-zero stiffness characteristic. The three-freedom parallel vibration isolating platform comprises a fixed platform connected to an external base platform, a movable platform for bearing vibration-isolated equipment, branched chains and a quasi-zero stiffness mechanism, wherein a movable platform bottom plate 12is connected with one branched chain in a radial direction every 120 degrees by taking the centroid as the center of circle, the branched chains are arranged on a supporting frame bottom plate 7 of the fixed platform; a vertical spring 6 is supported on the movable platform bottom plate 12 in the radial position, the bottom of the vertical spring 6 is supported on a fixed platform bottom plate 1;the movable platform bottom plate 12 is connected with the branched chains through a rotary shaft mounting base 19; each branched chain comprises a parallelogram mechanism which consists of a first rotary shaft 18, a second rotary shaft 18a and two connecting rods 11, so that the movable platform is kept in the horizontal state while moving in the space; and a horizontal spring 10 and the vertical spring 6 define a quasi-zero stiffness mechanism. The three-freedom parallel vibration isolating platform is simple and compact in structure, has flexible motion characteristic, and meets space three-translation-freedom vibration isolating requirements.

Description

technical field [0001] The invention relates to a parallel mechanism, in particular to a three-degree-of-freedom parallel vibration isolation platform with quasi-zero stiffness characteristics. Background technique [0002] Vehicle-mounted instruments and equipment will inevitably be affected by vibration during vehicle driving. This vibration will affect the reliability of on-board instruments and equipment. [0003] The vibration received by mechanical equipment can be decomposed into vibration in six coordinate directions. my country's military standards and the vibration and shock standards of some precision instruments and equipment all put forward clear requirements for the vibration and shock responses in the three translation directions. The three-degree-of-freedom vibration isolation mechanism can well meet this requirement. [0004] Compared with the vibration isolation problem of medium and high frequency vibration, it is more difficult to solve the problem of ...

AI Technical Summary

Problems solved by technology

The vibration isolation device is simply arranging multiple single-degree-of-freedom quasi-zero-stiffness vibration isolators so that the upper platform can only move in translation on the three axes of X-axis, Y-axis, and Z-axis, and multiple vibration isolators are easy to affect each other , reduce the vibration isolation performance of the platform, and at the same time, the platform has a small working space, a large volume and a complex structure, which limits the engineering application

[0008] To sum up, the existing three-degree-of-freedom vibration isolation mechanism cannot obtain good low-frequency vibration isolation performance, and the existing quasi-zero stiffness vibration isolator with positive and negative stiffness in parallel has good low-frequency / ultra-low-frequency vibration isolation performance. However, three-degree-of-freedom vibration isolation cannot be achieved. The limitations of these technologies prevent them from being used to solve low-frequency three-degree-of-freedom vibration isolation problems

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