| Based on the CAD/ CAM integrated technique, the design and manufacture of conjugate cam are studied and a CAD/ CAM integrated software system is developed. The combination of different follower's movement curves is discussed and a combined movement curve of the follower is generated for the conjugate cam with complex profile. The calculating formula is given for the theoretical profile of conjugate cam and a simple method is presented for the generation of the actual profile coordinates. Taking the manufacture of the cam into account some methods for the representation of cam profile with different jointed arcs are summarized. Two methods, named Calculation Method and Drawing Method respectively, are presented. Based upon the consideration of the interpolation-error, the arc-interpolation with multi-points (called Big Spaced Arc-interpolation Method) is put forward so that the cam profile can be represented with fewer arc segments. A module for NC codes generation is developed and the NC codes for cam manufacture can be generated automatically.The main points of the paper are as follows:Firstly, the current methods for the theoretical profile coordinates of conjugate cam are analyzed and the calculation formula is given for the theoretical profile coordinates. The combination of different follower's movement curves is studied and a combined movement curve of the follower with better.performance can be generated for the conjugate cam with complex profile. A software written by VC++6.0 is developed to calculate the coordinates on the theoretical profile of conjugate cam.For the calculation of the actual profile coordinates, the paper presents a new method based on the development to AutoCAD. This does not need complicated mathematical calculation but gets the coordinates on the actual profile of the cam simply by a program written with AutoLISP. The related menus and dialogue boxes are developed. By this way the data and the drawing of the cam actual profile can be generated automatically, and whether the profile is correct or not can been found very directly in the manner of drawing as well.The methods for arc-interpolation are analyzed in the paper and the calculation formula are given for arc-interpolation under various conditions. Calculation Method and Drawing Method are presented for arc-interpolation. In order to decrease the segments ofthe arcs, the Big Spaced Arc-interpolation Method is put forward under the consideration of interpolation error. The judging criterion is given for clockwise arc and counter-clockwise arc. The modules are developed for calculating the parameters of the arcs and automatically generating NC codes.Taking a certain conjugate cam as an example, the paper introduced the processes and the operation in the system from the design, arc-interpolation to generation of NC codes and cutter location simulation for the cam profile. The reliability and practicability of the software system are proved.
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