An experimental investigation carried out of the coastdown characteristics of a variable-speed d.c. motor and a motor-rotor system is detailed in this paper. The characteristics obtained through an XY recorder in terms of speed vs. time are replotted in terms of deceleration vs. speed for both unreleased and released conditions of the motor commutator carbon brushes during the coastdown experiments. The deceleration vs. speed curves (coastdown curves) for the motor-rotor system resemble the classical Stribeck diagram of friction. © 1987.

G. Santhanakrishnan

B. V.A. Rao

IIT Madras is a public technical and research university located in Chennai, Tamil Nadu. Founded in 1959, it is recognised as an Institute of National Importance.

IIT Madras has been ranked as the top engineering institute in India for four years in a row by the National Institutional Ranking Framework of the MHRD

It currently offers undergraduate, postgraduate and research degrees across 16 disciplines in Engineering, Sciences, Humanities and Management. About 596 faculty belonging to science and engineering departments and centres of the Institute are engaged in teaching, research and industrial consultancy.

IIT Madras

Commutator carbon brush effect on the coastdown times of a horizontal motor and a motor-rotor coupled system

Wear

An experimented investigation of the coastdown characteristics of a two-rotor system consisting of a variable-speed d.c. motor driving a flexible rotor on two journal bearings is presented. The characteristics are plotted in terms of decelaration versus speed for various operating conditions (speed, lubricant type, misalignment and commutator carbon brushes). The coast-down curve resembles the classical Stribeck friction diagram and hence can be used to evaluate the transition speed of journal bearings of rotating systems. The results confirm that this simple technique provides a measure of the friction present and indicates the mechanical condition of the rotating assemblies. © 1983.

An experimental investigation of tribological effects on coastdown phenomena in horizontal rotating machinery

Proceedings of the Institution of Mechanical Engineers, Part A: Power and Process Engineering

Windage Loss in Larger High-Speed Gears

A S L E Transactions

Coastdown Time as a Mechanical Condition Indicator for Vertical Axis Motors with Grease-Lubricated Ball Bearings

The Behavior of Plain Hydrodynamic Journal Bearings During Starting and Stopping

Wear Characteristics of Plain Hydrodynamic Journal Bearings During Repeated Starting and Stopping

Journal	Wear
ISSN	00431648
Open Access	No