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This article presents dynamic model for numerical researches of oscillations of the main frame of an electric locomotive taking into account the impact of longitudinal efforts arising in the automatic coupler.

Considered forced oscillations of four-axle vehicle with dual spring suspension. It is obtained that the movement system with six degrees of freedom with sufficient accuracy can be represented by a system with two degrees of freedom. Therefore, the vehicle body has two degrees of freedom: lateral skidding and wobbling, Bouncing and galloping trucks will be neglected. The total number of degrees of freedom of the model equal to two. The method, which leads to a closed solution of the forced oscillation. Defined. That tends and to (n = 1, 2,…), the amplitude of the oscillations will be unlimited. Therefore, the parameters k1, k2 and T must be selected on the basis of required values of amplitudes. As a result of research compiled by the differential equation of motion of the system and obtained analytical solution for the case of external piecewise constant driving force.

The new dynamic effects, arising in problems of vibration protection of objects at external perturbations from the bearing surfaces, are considered.A method of constructing mathematical models for the vibration-protection system, in which protection of an object has two degrees of freedom, is developed. The possibilities of the introduction of additional ties in the form of devices for converting the movement are shown. The possibilities of using screw non self-locking mechanisms with nuts - flywheels, reduced moment of inertia may be regulated are estimated. The technique of constructing frequency chart, showing the possible forms of realization of the dynamic effects, is offered. The conditions of the realization of new physical effects in the form of simultaneous dynamic vibration damping of the solid at the same time by two coordinates at the kinematic system perturbation are determined. Results of numerical modeling are given.

Features of interaction of elements of a dynamic quencher of oscillations in the form of a rigid body with two degrees of freedom are considered. It is shown that the dynamic quencher is interpreted in structure of mechanical oscillatory system with object of protection as additional negative tie which can be presented by the generalized spring. Dynamic ruggedness of the generalized spring depends on the frequency of external indignation and defines manifestations of dynamic properties, characteristic for the modes of dynamic blanking out of oscillations. The generalized spring possesses properties of a quasi-spring that creates possibilities of various transformations of structure of system. Introduction of concept of the generalized transmission ratio of the lever ties arising between coordinates of the movement of elements of a dynamic quencher is offered. Forms of the transfer relations of lever ties are in univocity with system of the chosen coordinates. The transfer relations of lever ties allow to detail forms of mutual movements of elements of system. The method of creation of mathematical models is developed for an assessment of lever properties of movements of mechanical oscillatory systems.

The paper considers the influence of the force characteristics of the damping apparatus on the value of the maximal longitudinal forces arising between the cars. Using the computer program MSC.ADAMS, we performed the simulation of shunting collisions of cars and train transient movement modes. The dependences of the maximal forces at cars' collision at various velocities on the shape of the elastic elements' force characteristics are determined. The operation of various shock dampers for the case of the train starting off electric braking and movement through the parts of the longitudinal track profile was estimated. It is shown that shock dampers with a rapidly growing line of load lead to the emergence and propagation of large shock forces along the train, while a slow growth of the force leads to their reduction due to the amplitude increase in elastic vibrations propagated along the train length . We propose to use high-energy-damping devices to reduce the longitudinal forces in the train, which are characterized by the force slew rate substantially depending on the compression velocity of the shock damper.