| For perfect kinematics and dynamical characteristics, cylindrical cams are widely used in mechanical field. For structure complex, design and manufacturing difficult, though the CAD and CAM technologies are having been in progress, the expert CAD and CAM systems are also built, most of which are nonfunctional function and weak practicability. In order to improve on the generality and practical applicability of cylindrical cams' CAD/CAM technologies as well as the design efficiency of cylindrical cams, it is extremely urgent to develop a full-function cylindrical cams'CAD/CAM system. For the cylindrical cams, this dissertation researched the profile equations, theory of non-equant machining, three-dimensional parametric modeling, numerical control machining, etc., on this basis, a full-function cylindrical cams'CAD/CAM system was developed. In this paper, the following works have been accomplished:(1) For Cylindrical Cam with translating roller follower, cylindrical cam with oscillating roller follower and cylindrical indexing cam, the theoretic profile and contact angle of roller equations are derived by the theories of coordinate transformation and conjugate surfaces.(2) The control principle and method of non-equant machining for cylindrical cams are researched, the contour surface normal error' mathematical model of cylindrical cams'nan-equant machining is established, the method can meet the high precision demand for the cam slot or cam lobe crest and it was verified by case calculations, and also make up the shortcomings of equant machining for cylindrical cams.(3) The relevant model of the programmable feed speed and the actual feed speed of the cylindrical cams'machining in numerical control machine is established, the tool's actual feed speed become almost constant by revising the programmable feed speed of each numerical control program segment, then lessen the influence of the contour surface's manufacturing quality which caused by the alteration of actual feed speed and improve the cylindrical cams'surface quality.(4) The cylindrical cams'three-dimensional model was built based on SolidWorks and Visual Basic software platform by virtual manufacturing, and then developed a full-function cylindrical cams' CAD/CAM system, which realized the parametric design and solid modeling of cylindrical cams, as well as,the NC codes could generate automatically.(5) The NC machining experiment, based on LEADWELL V-60A 4-axis linkage machining centre, for several typical cylindrical cams is accomplished, the cam's profiles are also measured, the result verified the theoretical research results agree with the experimental results. |
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