ABSTRACT
Maize, known in many English-speaking countries as corn, is a grain domesticated by indigenous people in prehistoric times. The Aztecs and Mayans cultivated it in numerous varieties throughout central and southern Mexico, to cook or grind in a process called nixtamalization. The crop spread throughout America and later around the 1250 BC it spread to all corners of the region. Any significant or dense populations in the region developed a great trade network based on surplus and varieties of maize crops. After European contact with the Americas in the late 15th and early 16th centuries, explorers and traders carried maize back to Europe and introduced it to other countries through trade. Maize spread to the rest of the world due to its popularity and ability to grow in diverse climates. The existing methods of corn de-husking in agriculture industry consist of breaking the grains by hand or by using large machinery for shelling, both of which are not effective for a developing economy like Nigeria where farmers have little money for investment. Hence, there is a need for an innovative idea or product that is feasible, safe, cost effective and productive for the Nigerian farmer. The objective of this work is to design and develop an improved maize shelling machine in terms of better time management, affordable cost, portability and mechanical efficiency. The method used involved selecting appropriate materials, and utilization of theories of failure that enable the determination of allowable shear stress on the bearing supports. It features the design calculations necessary for the completion of this work. The production cost of the Maize Sheller is ₦34500 and it is powered by a 5hp electric motor.
TABLE OF CONTENTS
DECLARATIONi
CERTIFICATIONii
DEDICATIONiii
ACKNOWLEDGEMENTSiv
ABSTRACTv
TABLE OF CONTENTSvi
LIST OF FIGURESix
LIST OF TABLESx
CHAPTER ONE
INTRODUCTION1
Background Information1
Problem Statement2
Aims and Objectives of the Study2
Justification of the Study3
CHAPTER TWO
LITERATURE REVIEW4
2.1Maize4
2.1.1Origin, Classification and Botany of Maize4
2.1.2Importance and Uses of Maize4
2.2Maize Shelling5
2.2.1Traditional / Manual Maize Shellers8
2.2.2Mechanized Maize Shellers11
CHAPTER THREE
MATERIALS AND METHODS14
3.1Design Considerations14
3.2Design Analysis and Calculations14
3.2.1Hopper Design15
3.2.2Main Frame Design16
3.2.3Threshing / Shelling Bars Design16
3.2.4Shaft Design17
3.2.5Prime Mover Design21
3.2.6Pulley Design21
3.2.7Belt Design22
3.2.8Groove Dimension Design25
3.2.9Screen Design30
3.2.10Key Design30
3.3Design of all Component Parts31
3.4Machine Description and Operation32
3.5Material Selection for the Machine Components35
CHAPTER FOUR
CONCLUSION AND RECOMMENDATIONS38
4.1Conclusion38
4.2Recommendations38
REFERENCES39
APPENDICES42
LIST OF FIGURES
FIGURETITLE PAGE
Maize Cobs 2
Maize Shelling by Hand9
Varieties of Hand Maize Shellers Using Different Methods10
Sheet Metal Maize Sheller Forming Jig11
Amizy Maize Sheller11
First Vidhata Shelling Machine12
Second Vidhata Maize Sheller13
Schematic Diagram of the Hopper15
Distributed Weights Acting on the Shaft at Different Sections18
Exploded View of the Maize Sheller Showing Component Parts33
Isometric and Orthographic Drawings of the Maize Sheller34
Conceptual Drawing of the Maize Sheller34
3D Drawing of the Assembly35
LIST OF TABLES
TABLETITLE PAGE
Comparison of Maize Shelling Methods8
V-belt Horsepower Design Data23
Deep Groove Bearing Selection Factor Design Data25
Recommended Life Value of Bearings Design Data30
Construction Materials for the Maize Sheller and Their Specifications36
