Devising a Drum-Buffer-Rope System

This paper focuses on the investigation of the autoparametric coupling effects and modal interactions in a suspension rope system with a time varying length. Equations of motion of a multi-degree-of-freedom discrete, non-stationary and non-linear model are presented and are used to analyze the dynamic response of an elevator suspension rope system under resonance conditions. The equations of motion involve quadratic and cubic non-linear terms which are responsible for the modal interaction between the lateral and longitudinal oscillations of the rope and the car motions. The model takes into account the periodic excitations caused by motion of the host structure. The results confirm that adverse responses may arise and internal autoparametric resonance phenomena may occur.

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Discrete-continuous simulation and analysis of forced oscillations of (heavy) rope of crane loading mechanism in its process

Naukovij žurnal «Tehnìka ta energetika» ◽

10.31548/machenergy2020.03.181 ◽

2020 ◽

Vol 11 (3) ◽

pp. 181-186

Author(s):

Yu. V. Chovnyuk ◽

◽

I. M. Sivak ◽

Keyword(s):

Internal Friction ◽

Cross Sections ◽

Integrodifferential Equation ◽

Forced Oscillations ◽

Harmonic Oscillations ◽

Continuous Simulation ◽

Considerable Length ◽

Rope System ◽

Oscillatory Processes

The analysis of forced oscillations and waveformations of heavy ropes of hoisting mechanisms of cranes in the processes of starting the latter is carried out. The main parameters of the resulting waveforms in the ropes for different ways of lifting the load ("with a pickup", "by weight") are determined. The influence of gravity on the rope and the longitudinal oscillations arising in it, as well as on the longitudinal waveforms arising inside it are investigated. The rope of the lifting mechanism, in this case, is considered as a tensile rod. The laws of motion of cross-sections of ropes are established, according to which the forces arising in ropes are minimized during the startup of hoisting mechanisms of cranes. The application of the integrodifferential equation, which adequately describes the oscillations of the rope system of cargo cranes, and also takes into account the frequencyindependent internal friction in these systems, which accompanies the oscillatory processes in the ropes during transient reagents for their differentiation by different ways of lifting loads. The parameters of the established harmonic oscillations of the rope system of cranes for long-term lifting of the load and taking into account the inertial properties of the rope (considerable length), as well as the magnitude of the static movement of the rope (for different ways of lifting loads) are determined.

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Laboratory Device for Checking the Functionality of the Elevator Rope Sensors

Management Systems in Production Engineering ◽

10.2478/mspe-2021-0008 ◽

2021 ◽

Vol 29 (1) ◽

pp. 59-64

Author(s):

Leopold Hrabovsky ◽

David Borovsky

Keyword(s):

Axial Force ◽

Inclination Angle ◽

Structural Design ◽

Indirect Method ◽

Tensile Force ◽

Force Sensor ◽

Tensile Forces ◽

Laboratory Device ◽

Measured Load ◽

Rope System

AbstractThe paper describes the structural design of a laboratory device that allows for presenting operation, simulating work procedures and checking functionality of the elevator “rope sensors” when equalizing different tensile forces in partial ropes of a rope system of traction elevators. The laboratory device is modified for checking operations of commonly used rope sensors. In an overwhelming number of cases, elevator technicians use them for setting up the unequally distributed tensile forces in elevator ropes. The device is equipped with three, mutually attached pulleys, over which the rope is installed. The unknown tensile force in the rope is determined by an “indirect method”, i.e. from the resultant of the forces of the rope bent over the pulleys, which have an effect on the force sensor. The tensile force along the rope axis can be determined numerically, but also experimentally, from the inclination angle of the rope installed on the pulleys, diameter of the pulleys, diameter of the rope and the force detected by the force sensor of the stretched rope. The paper presents experimentally obtained tensile force values at the rope sensor, deduced from stretching the rope. The paper also describes the procedure for determining the measured load in the rope by rope sensors of the SWR, SWK and RMT-1 types based on the variable axial force in the rope.

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Dynamic analysis of high-speed traction elevator and traction car–rope time-varying system

Noise & Vibration Worldwide ◽

10.1177/0957456519827929 ◽

2019 ◽

Vol 50 (2) ◽

pp. 37-45 ◽

Cited By ~ 2

Author(s):

Qing Zhang ◽

Yu-hu Yang ◽

Tao Hou ◽

Rui-jun Zhang

Keyword(s):

Dynamic Model ◽

High Speed ◽

Longitudinal Vibration ◽

Variable Mass ◽

Traction Force ◽

Vertical Vibration ◽

Time Varying ◽

Quintic Polynomial ◽

Input Motion ◽

Rope System

In this study, the compensating ropes and tension device on elevator vibration, as well as the car and hoisting ropes between the top of the car and traction wheel in a high-speed traction elevator lift system, were considered a system to analyze the effect of traction force. In addition, the vertical vibration of the system was used as the research object. The influence of hoisting ropes quality was measured, and a time-varying dynamic model with variable mass, damping, and stiffness for the car–hoisting rope system was constructed from the perspective of time-varying structural mechanics. Simultaneously, the ideal running state of the elevator, which is fitted by using the quintic polynomial, was utilized as input motion parameter. Then, a case study was conducted by using the fine integral method for the vertical vibration dynamic model of the car–hoisting rope system. Finally, the nonlinear vertical vibration response of the car–hoisting rope system during the operation of high-speed traction elevator was obtained. Results indicated that the influence of traction force, compensating ropes, and tension device on the vibration of the car–hoisting rope system when the elevator is in the upward process is greater than when the elevator is in the downward process. In addition, the low quality of the elevator car leads to the production of strong longitudinal vibration. The linear density of the hoisting ropes has a slight effect on the longitudinal vibration of elevator.

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