SU1401314A1 - Mechanical model for investigating interaction of oscillating system with vibration exciter - Google Patents

Abstract

This invention relates to a testing technique. The aim of the invention is to increase the information content. The model contains a moving mass 2, suspended from the base 1 by means of springs 3, 4, and a limiter of 5 oscillations. On the moving mass 2, on the side of the limiter 5 oscillations, an elastic gasket 6 is installed. With the help of a spring-pressing mechanism 3, 4, between which mass 2 is set, the gap between the elastic gasket 6 and the limiter can be adjusted. Model makes it possible to realize both soft and rigid piecewise linear elastic characteristics of the oscillatory system and a nonlinear skeleton curve of amplitude-frequency characteristic, which makes it possible to use the model to test the operation of test vibration control systems. 7 il. S (L with 4

Description

The invention relates to a test apparatus, specifically to devices for studying the interaction of mechanical oscillatory systems with a source of oscillations, and can be used for the methodological certification of test vibrations.

The aim of the invention is to increase the p | format of research.

FIG. 1 shows the mechanical model of the oscillatory system; in fig. 2 - another characteristic of the system with a gap; in fig. 3 - frequency characteristic of a system with elastic hardness- |: oops; in fig. 4 - elastic characteristic of the system without a gap; in fig. 5 - amplitude-o-frequency characteristic of the system with upward characteristic; in fig. 6 - amplitude-frequency characteristics of the system and stimulus; in fig. 7 - dependence of the current in the moving coil of the vibration-locomotive on the frequency corresponding to the amplitude-frequency characteristics of the system and the vibration exciter.

The mechanical model contains the base 1, the moving mass 2 suspended to the Principle 1 by means of springs 3 and 4, the oscillator 5, the elastic gasket I mounted on the moving mass 2 from the side of the limiter 5 oscillations with the possibility of interaction with and the mechanism for tightening the springs 3 and 4, made S in the form of a screw 7, nuts 8 and 9, and mounting ayki 10. The movable mass 2 is placed between the springs 3 and 4.

The model works as follows. The base 1, which is rigidly connected with the moving part of the vibration exciter, makes a salivary movement. The elastic forces arising from the deformations of the springs 3 and 4 are transmitted to the moving mass 2 and they oscillate with it. The oscillations of the moving mass 2 and the base 1 are measured with the help of sensors 11 12. With oscillations of the moving mass 2 1, the gap within the gap d (Fig. 1) is an oscillatory system, formed by the elasticity of the springs $ and 4 and has a moving mass 2 the linear characteristic F (x) (Fig. 2). With an increase in the amplitude of oscillations, the elastic gasket I) interacts with the limiter 5 oscillations, the slope of the elastic characteristic F (X) increases and, in a manner, the piecewise linear 1a rigid elastic characteristic of the oscillatory system is realized. This elastic characteristic corresponds to the skeletal curve of the amplitude (frequency-response characteristic of the oscillating system (Fig. 3): sections A correspond to a stable mode of oscillation, and section B corresponds to the mode of oscillations under breakdown conditions, characterized by a sudden change in the amplitude of oscillations of mass 2 and

accordingly, a stepwise change in the reaction of springs 3 and 4 to base 1.

In the case of the initial installation of mass 2 without a gap D, which can be ensured by compressing the springs 3 and 4 during rotation of the screw

. 7 and nuts 8 and 9 of the preload mechanism, a soft elastic characteristic F (x) of the oscillatory system (Fig. 4) is realized, where the section O-a is the deformation of the elastic gasket 6, when the gasket 6 separates from the vibration limiters 5 and a deformation takes place springs 3. This soft elastic characteristic of the system corresponds to the skeleton curve of the amplitude-frequency characteristic (Fig. 5), where the dotted line indicates an unstable branch with fluctuations in

, breakdown mode.

The invention makes it possible to realize linear and various non-linear elastic characteristics affecting the interaction of an oscillating system with an exciter. Nonlinear amplitude curve 5

The frequency response implemented by the model makes it possible to extend the informativeness of the research when checking the efficiency of the vibration exciter and its control system, as it allows reproducing the loading modes of the vibration exciters with an abrupt change in load. Using a series of models with different sizes of moving mass, it is possible to investigate the effectiveness of vibration exciter control systems in a wide range of loads in the working frequency range. Experimental results (Fig. 6 and 7) showed that using the proposed model, you can create a variety of test modes vibration settings.

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Claims (1)

Invention Formula A mechanical model for studying the interaction of an oscillatory system with 45 by an exciter comprising a base, a moving mass, raised to the base by means of springs, and an oscillation limiter installed on the base, characterized in that, in order to increase the informativeness of research, it is equipped 50 with an elastic gasket installed on the moving mass on the side of the oscillation limiter with the possibility of interaction with it, and a spring compression mechanism, and the mobile mass is placed between the springs. 1.2 at d Fie.2 Fi-gC W 50 FIG. 3 SO f, 0.8 0.4 1.0 0.8 06 0.4 0.2 1L QM 02 A 1, A 1 mN d -00 $ Fi gb /, Hz