Reverse Research Of The Disc Cam Mechanism With Translating Follower Along The Axis

Cam mechanism,which is used extensively in various types of machinery industry, has some functions such as transmission, track-oriented and process control. The reverse design and analysis of cam mechanism, which can determine the transmission characteristics and design intent of the prototype, are used to design and manufacture high-quality spare parts of the prototype cam or to absorb the design and manufacturing technology of the prototype cam for transformation and innovation in the design of cam mechanism. So the reverse design of cam mechanism has been a research hotspot in engineering fields in recent years.The key to the reverse design of cam mechanism is that the prototype cam's followers or the motion law of driven system are analyzed and determined according to the profile of the prototype cam and the measured value of the cam body. In this paper, the planar cam mechanism was used as the targeted to research and explore the ways and means of solving the key issues.This paper introduced some familiar curve fitting methods, such as the spline interpolation method, least square method and the B-spline methods, compared the advantages and disadvantages of various fitting methods ,and determined the non-uniform cubic B-spline fitting and fitting equation of the contour curve. And then the paper illustrated the importance and necessity of the cam contour smoothing in the reverse design, introduced the advantages and disadvantages of the curve smoothing methods such as the least squares method, the minimum energy method, the discrete energy method and other smoothing methods commonly used, and established the discrete energy contour smoothing and its computational process.According to cubic B-spline theory, given the polar radius, the derivative functions of polar radius and the expression of normal vector of the contour curve, and then established the algebraic formulas of the follower's quantity of motion and the pressure angle of mechanism by using with the known parameters and size of machine of the cam profile.Take the cam mechanism with translating follower in a certain type of knitting machine for an example, feasibility and accuracy of the method in this paper was verified by using reverse design of the example by Matlab programming. Finally, processed the reverse cam in machining simulation by UG software.