Atlas of performance curves for crank-rocker and slider-crank linkages.
Abstract:ESDU 81033 presents an "atlas" of graph sheets that directly provide nine important performance parameters related to the motion of the crank including: a) angle between the coupler link and the line of centres; b) angle between the rocker link and the line of centres; c) angle between coupler and rocker (the transmission angle); d) coupler velocity coefficient; e) rocker velocity coefficient; f) coupler acceleration coefficient; g) rocker acceleration coefficient; h) coupler end-load coefficient; i) crank torque coefficient. The method covers all four bar linkages: crank-rocker, slider-crank, parallel-coupler, and offset swinging-block. Each graph sheet includes a scale sketch of the linkage. The atlas can be used by itself, with interpolation as required, to examine the kinematic and dynamic characteristics of a chosen linkage, to compare, for example, the maximum values of torque and force coefficients in conjunction with extreme transmission angles. The rate of change of the various parameters can also be derived with the atlas, or questions concerning the space occupied by the mechanism as determined by the angle of swing between dead centres can be answered.
|Data Item ESDU 81033|