Akademik Veri Yönetim Sistemi
Tez Türü: Doktora
Tezin Yürütüldüğü Kurum: University of Salford, Faculty of Enginering, Department of Aeronautical and Mechanical Engineering, İngiltere
Tez Danışmanı: Alan Redford
Tezin Onay Tarihi: 1993
Tezin Dili: İngilizce
Desteklendiği Program: Diğer
Özet:
This study is part of a SERC research project. The overall objective
of the research program was to
investigate the technical and economic feasibility of extending the use of a
robotic printed circuit board assembly (PCBA) cell to perform rework and in-process inspection of
single-sided PCBAs based on a batch size of one.
The main aim of the work presented in this thesis was to identify and develop appropriate rework methods, hardware tooling and robot programs. The most important aspect of this was to fully automate the rework of surface mount and through hole electronic components.
The purpose of chapter 1 is to give a general overview of PCBA technology. It introduces electronic assembly and briefly describes the assembly processes with the intention of facilitating the development of the fully automated PCBA robotic rework cell.
In chapter 2, the current state of PCBA manufacturing is examined in depth based on zero defect assembly or high quality achievement. It provides a brief review of the common PCBA defects together with their causes. Later sections study industrial robots and explores the possibility for achieving automated rework using an industrial robot. This chapter also describes the aims and objectives for hardware.
Chapter 3 reviews the manual rework activities, manual rework
machines, methods and tooling. It then compares the current
desoldering/soldering tooling and methods. It also outlines the critical
parameters for both through hole (TH) and surface mount (SM) rework and
determines the rework requirements for an ideal rework station.
Chapter 4 describes the most important work of the study. It considers the possibility of developing automated rework methods, procedures and suitable hardware tooling. It proposes a configuration for a fully automated robotic rework cell together with essential experimental work. It presents detailed rework procedures for SM and TH automated rework and it concludes with the determination of a functional system specification and further analysis based on a top-down approach systems analysis.
Chapter 5 presents the detailed experimental studies carried out to determine various rework parameters and process variable settings.
Chapter 6 describes the layout of the rework cell, interfacing and pneumatic control circuits at the top level and then gives a summary of the hardware design, electronic and electrical integration of the rework tooling and briefly introduces the structure and data requirements for the robot programs. It basically explains how the ideas developed in chapter 4 have been manufactured and implemented.
Chapter 7 discusses the technical feasibility for developing a fully automated robotic rework cell based on the automated rework experiments that were done using demonstration PCBAs and some representative components. It also discusses the validation of the experimental studies results, of which are presented in chapter 5.
Chapter 8 compares the robotic rework cell with manual and semi-automated rework station alternatives based on quality reliability, effectiveness and the rework cycle time. It also presents further installations and improvement requirements. In the second section, it identifies the installation cost of manual, semi-automated and automated rework alternatives, and models semi-automated and automated rework to determine the cost of reworking per component for both PCBA technologies. It also compares these with the intention of justifying the investment in automated rework equipment.
Finally chapter 9 presents conclusions about various aspects of PCBA technology and the technical and economic feasibility of using a robotic rework cell. It indicates the benefits and limitations of such a rework cell and makes recommendations for general and specific future work that is required in this field of study.