Rapid Optimal Design Of Non-circular Gear-drive

Different from circular gear-drives with constant speed ratio, non-circular gears can realize the variable velocity-rate transmission , they are widely used in light industry-,textile-,tobacco- and foodstuff-machines, and play an important role in the creative design of mechanism. But because of its complex calculation in design and difficult manufacture , the more widely application of non-circular gear-drive has been limited for a long time. From 70s of the 20th century , following the development of computer and numerical control technology , a new tide of researching and application of non-circular gear-drive , so called the 'rediscovering' of non-circular gears , is coming in .The NC technology has solved the difficulty of manufacture for non-circular gears , But all the design methods (include CAD methods) for non-circular gear-drive resent by current literatures are based on repeated analysis , that is : give a group of parameters , get the analysis - or proof-calculation result , if the result does not satisfy the design request , then modify the given parameters , analysis -or proof-calculate again . The choice of parameter is blind in a certain degree , the design period is long and the design quality is difficult to guarantee .Based on complex calculation in non-circular gear-drive's design, This paper introduces the optimization technique into the design of non-circular gear-drive , because the procedure can be illustrated as : given the variation rule of speed ratio , choice a group of geometric parameters , under the constraints of keeping the tooth correctly joggled and transmitted continuously ( as well as enough strength and rigidity) , to approach the given variation law of speed ratio as near as possible .It is characteristically an optimization procedure:Mathematical models of optimal design for three kinds of closed-type non-circular gear-drives are presented in this paper : the ellipse gear-drive , the variant ellipse gear-drive and the eccentric gear-drive . deduce and perfect a set of calculation formula for the design of non-circular gear-drive , compile the optimization program of non-circular gear-drive's design.Compare the results of examples by using optimization methods, it proves that Using optimization methods to design non-circular gear-drive is a synthesis-basedmethod , it can avoid the repeated modify of parameter and the repeated proof-calculation in design , and satisfy the varied engineering demands , improve the design quality and make the design rapid and more successful . It has an important sense.