Design of a child resistant cosmetic closure mechanism

Abstract

This project was conducted in order to design a child-resistant cosmetic closure mechanism for Toly Ltd., the industrial partner. The academic objectives consisted of critical reviews of standards and patents, generating alternative working principles of the child-resistant package as well as conducting an FMEA and DFMA exercise of the selected final solution. On the other hand, the industrial objectives consisted of identifying the design specifications, generating alternative solution concepts and selecting the best solution based on several criteria. Moreover, prototyping development and testing of the selected solution, as well as a detailed design for mass production for the selected solution, were also required. The basic design cycle was used to have a logical structure within this project. This allowed the implementation of various tools and methods in the early stages of design, such as the PDS, QFD, and SCAMPER. Later stages utilised other approaches such as 3D modelling and rapid prototyping. Various alternative concepts were produced, analysed and evaluated through brainstorming, creative thinking, numerous analyses as well as a decision matrix. The selection process comprised elements such as manufacturability, assembly, and child resistance. Furthermore, a number of physical prototypes were developed using cutting-edge equipment at the engineering faculty, which were produced from CAD models. When the physical prototype was completed, the design was examined and tweaked to meet both the academic and industrial objectives while facilitating injection moulding and mass production while lowering the risk of failure during manufacture. Finally, the changes were implemented to the 3D CAD models.