Study On CAD Of The Variable-pitch Screw Based On Pro/E

Variable-pitch screw is an important transporting device used in the modern packing machinery. It plays an key role in transporting objects or containers such as bottles, jars and boxes etc. , which are arraying regularly or irregularly in batches, to the packing position one by one and steadily according to the appointed technical requirements. First of all, this article researches the formation of the Variable-pitch screw's spiral slot when the commonly used 3-part-sectional screw is transporting the columnar objects, establishes the mathematical model of the tangent, intersecting-point spiral, bottom-slot spiral, and then researches the way to establish the 3-D parametric solid model with CAD tools such as Pro/E and finally accomplishes it.In order to adapt to the variety of the containers'shapes, the article researches the formation of the spiral slots of the screw while they are transporting the oval and rectangular objects, and then establishes respectively their mathematical model of the tangent, intersecting-point spiral, bottom-slot spiral. And also establishes the 3-D parametric solid models of these two types of the variable-pitch screws in Pro/Engineer.With the 3-D parametric solid model from Pro/Engineer, manufactures the variable-pitch screw directly by Rapid Prototype and CNC tools, changes the traditional complicated way of variable-pitch screw's manufacturing and machining used before.