AUTOMATIC HAND DRYER WITH TEMPERATURE DISPLAY

ABSTRACT

This project deals on the design and construction of automatic hand dryer with temperature display facility which is capable of drying a wet hand placed under its vent goes of automatically. It corporate a temperature sensing and displays unit which displays the temperature of the blown out air. This system is designed in top-down methodology using passive and active components sensors (LM35 & LDR) at the input to sense temperature and hands respectively. The control unit is made up of signal conditioning unit, voltage comparator and frequency generator, and decimal counting unit. The output interface comprises transistor, driver, actuator, Electromagnetic relay and a –digit seven segment Display. The sensor are installed at the front of the blower and this device dries with warm air only. When a hand is placed under the vent to block the line of sight of the LASER Diode and LDR, the blower gets actuated and blows warm air. As the hand is removed, the blower stops automatically along side the temperature display. The principle behind the work of this system is that the hands must be opaque enough to block the line of sight of the opto coupler. This removes the stress, time and dangers associated with push button type. The result being automatic hand dryer with temperature display.

TABLE OF CONTENT

Title page       -           -           -           -           -           -           -           -           -           i

Certification page    -           -           -           -           -           -           -           -           ii

Approval page          -           -           -           -           -           -           -           -           iii

Dedication     -           -           -           -           -           -           -           -           -           iv

Acknowledgement               -           -           -           -           -           -           -           v

Abstract         -           -           -           -           -           -           -           -           -           vi

Table of content       -           -           -           -           -           -           -           -           vii

List of tables             -           -           -           -           -           -           -           -           -          ix

List of figures           -           -           -           -           -           -           -           -           x

Chapter One

1.1.           Introduction -           -           -           -           -           -           -           -           1

1.1.1.     Problem statement   -           -           -           -           -           -           -           1

1.1.2.     Aim and objectives              -           -           -           -           -           -           2

1.1.3.     Justification of the study   -            -           -           -           -           -           -           3

1.1.4.     Scope of the project             -           -           -           -           -           -           -           3

1.1.5.     Project report organization-           -           -           -           -           -           3

Chapter Two

2.1. Literature review          -           -           -           -           -           -           -           4

2.1.1. Analysis of the existing system      -           -           -           -           -           5

2.1.2. Theories and models relevant to the design -       -           -           -           6

Chapter Three

3.1. Automatic hand dryer with temperature display     -           -           -           9

3.1.1. Description of the system building blocks            -           -           -           9

3.1.2. Block diagram development into working circuit            -           -           9

3.1.3 System design specification             -           -           -           -           -           -           10

3.1.4. Power supply unit     -           -           -           -           -           -           -           11

3.1.5 Principle of operation of the system           -           -           -           -           -           12

3.1.6. System design calculation               -           -           -           -           -           13

3.1.7 The control logic circuit        -           -           -           -           -           -           14

3.2   The Ne555 timer                      -           -           -           -           -           -           14

3.3   Other System components     -           -           -           -           -           -           22

Chapter Four

4.1. Implementation, testing and result                 -           -           -           -           38       

4.1.2   Testing           -           -           -           -           -           -           -           -           38

4.1.3. Result -           -           -           -           -           -           -           -           -           39

4.1.4 Packaging        -           -           -           -           -           -           -           -           40

4.1.5. Bill of engineering quality   -           -           -           -           -           -           40

Chapter Five

5.1. Summary of achievement        -           -           -           -           -           -           42

5.2. Conclusion        -           -           -           -           -           -           -           -           43

            References    -           -           -           -           -           -           -           -           44

LIST OF TABLES

3.1 The system components list     -           -           -           -           -           -           -           35

4.1 Bill of engineering quantity -  -           -           -           -           -           -           -           40

LIST OF FIGURES

2.1       Physical layout of seven segment             -           -           -           -           -          -           8

2.2       Schematic diagram of seven segment       -           -           -           -           -           8

3.1       Block diagram of the system         -           -           -           -           -           -           10

3.2       Block diagram of the Regulated    -           -           -           -           -           -           12

3.3       Ne555 timer  -           -           -           -           -           -           -           -           -          14

3.4.      Internal block           -           -           -           -           -           -           -           -          15

3.5.      Pin out diagram -      -           -           -           -           -           -           -           -          15

3.6       Standard Ne555 astable circuit sensor     -           -           -           -           -           17

3.7       The blower    -           -           -           -           -           -           -           -           -          18

3.8       The LM35 integrated circuit sensor -       -           -           -           -           -           19

3.9       The LM35 wired circuit board       -           -           -           -           -           -           20

3.10    Voltmeter      -           -           -           -           -           -           -           -           -          21

3.11    Diagram of transistor           -           -           -           -           -           -           -          22

3.12.   Diagram IC linear voltage regulator 75xxICs      -           -           -           -           23

3.13    Photo-resistor -         -           -           -           -           -           -           -           -          24

3.14    The symbol for a photo resistor -  -           -           -           -           -           -           25

3.15    Voltage comparator ICs      -           -           -           -           -           -           -          27       

3.16    A typical Resistor    -           -           -           -           -           -           -           -          29

3.17    Resistor connected in parallel       -           -           -           -           -           -           31

3.18    Resistor in series      -           -           -           -           -           -           -           -          31

3.19    A typical electrolytic capacity -    -           -           -           -           -           -           32

3.20    A transformer           -           -           -           -           -           -           -           -          33
3.21    A typical PN junction Diode          -           -           -