METHODOLOGY FOR ANALYSIS OF THE INFLUENCE OF THE MECHANICAL ERRORS AND OF THE CLEARANCES ON THE PRECISION OF WATT AND STEPHENSON MECHANISMS

Abstract

THIS PAPER PRESENT A COMPUTING METHOD USED IN THE ANALYSIS OF THE PRECISION OF THE SIX LINKS WATT AND STEPHENSON MECHANISMS. IT IS STUDIED THE INFLUENCE OF THE MANUFACTURING ERRORS, WHICH APPEAR AT THE MANUFACTURING OF THE KINEMATICS LINKS, ON THE MOTION LAW OF THE OUTPUT LINK. THE MATHEMATIC MODEL IS DEVELOPED ON THE BASIS OF THE PARTIAL DERIVATIVES OF THE OUTPUT PARAMETERS WITH RESPECT TO THE MANUFACTURING PARAMETER OF THE MECHANISMS. THESE PARTIAL DERIVATIVES ARE COMPUTED WITH THE HELP OF THE INPUT-OUTPUT EQUATION DEVELOPED FOR WATT AND STEPHENSON MECHANISMS. THE SECOND PROBLEM PRESENTED IN THE PAPER IS REPRESENTED BY THE MATHEMATIC MODELING OF THE PRECISION DUE TO THE CLEARANCES FROM THE KINEMATICS JOINTS. THE MATHEMATIC MODEL IS DEVELOPED ON THE BASIS OF THE MONTE-CARLO METHOD. THE NUMERIC EXAMPLES LEAD TO THE CONCLUSION REGARDING THE CHOICE OF THE TOLERANCE INTERVAL IN SUCH A WAY THAT THE PRECISION REALIZED BY THE MECHANISM FITS IN THE TOLERANCE IMPOSED BY THE DESIGN.