Session: MR-7-1: Novel Mechanisms, Robots, and Applications

Paper Number: 117893

117893 - The Design of a Conjugate Screw Cam Mechanism: Applying Helical Joint in the Design of Cam Mechanisms 

This paper introduces a new cam mechanism design, the conjugate screw cam, which features a helical joint that enables the cam to be designed in both the radial and axial directions. The cam profile of the screw cam is generated spirally, and the double helix can form a form-closed type cam mechanism, making it over-constrained and allowing the mechanism to self-drive without the use of a return spring. The paper also discusses the periodic characteristics of traditional cam mechanisms and explores how the same feature can be retained in screw cam mechanisms through mechanical design.

An analytical solution for the screw cam mechanism is derived in this paper, which shows that the design of the cam profile can be decoupled into a planar cam and an additional axial directional screw. This allows for the traditional instantcenter method to be applied in generating the cam profile. A numerical example is presented to illustrate the implementation of the screw cam in a design condition that requires large lift but small space. Here, a translating concave-faced and convex-faced follower is used as an example of the conjugate screw cam mechanism. The results indicate that the screw cam has advantages over planar cam mechanisms in terms of pressure angle and space consumption, making it a promising area for further research.

Presenting Author: Tung-Hsin Pan National Taiwan University

Presenting Author Biography: My name is Tung-Hsin Pan. I'm now in my first year of my Ph. D. program. I belong to the deparment of Mechanical Engineering at National Taiwan University. I'm now under the advise of Prof. Kuan-Lun Hsu in Mechanical Design Laboratory. My research topic is mainly about design and kinematic analysis of the cam mechanism.

Authors:

Tung-Hsin Pan National Taiwan University
Kuan-Lun Hsu National Taiwan University