Journal of Machinery Manufacturing and Automation 
Journal of Machinery Manufacturing and Automation(JMMA)
ISSN:2307-9096(Print)      2307-9088(Online)
Editor-in-Chief: Prof. Juntong Qi (China)
Kinematic Analysis and Design of a Geneva Stop Mechanism Teaching Aid for Intermittent Motion
Full Paper(PDF, 1326KB)
Abstract:
The importance of intermittent motion in many equipment and machinery has called for the necessity to fully understand the various concepts of those systems where this type of motions are required in between continuous motions and also in those systems designed to perform automatic timing operations in robotic applications. This paper examines the kinematics analysis of a four (4) slot Geneva mechanism. The arbitrary model was developed and the effects of the force were neglected. The angular displacement of the wheel was investigated as is the function of crank angle and found to occur between ±π/4; 7π/4 to 9π/4; 15π/4 to 17π/4; 23π/4 to 25π/4 radians for the 1st, 2nd, 3rd and 4th revolutions of the crank angle respectively, in between these angles, there are dwelling periods. Also, for an assumed speed of the crank (12 rpm), the angular velocity of the wheel was obtained to be maximum and minimum between ± 3.0338 rad/sec at crank angles of 0°,2π,4π and 6π radians, for each of the 4 revolutions and that of angular acceleration was ±8.5161 rad/〖sec〗^2 at ±0.19,6.10 and 6.47,12.38 and 12.75,18.66 and 19.04 radians respectively. The timing of the tangent drive was expressed by the arc of each revolution of the driver or crank that the wheel was being indexed and the arc of each revolution that the wheel was at rest (idle).
Keywords:Geneva Wheel; Crank; Intermittent Motion; Kinematics; Kinetics
Author: Olurotimi Akintunde Dahunsi1, Anthony Yinka Oyerinde1, Ojo Phillip Bodunde1, Olugbenga Sunday Olunloyo1
1.Mechanical Engineering Department, Federal University of Technology, Private Mail Bag 704, Akure, Ondo State, Nigeria
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