automatic cooling system

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www.engineeringminiprojects.com

TABLE OF CONTENTS

CHAPTER NO. TITLE PAGE NO.

ABSTRACT v

LIST OF TABLES vi

LIST OF FIGURES vii

1. INTRODUCTION 1

1.1 AUTOMATIC COOLING SYSTEM 1

2. LITERATURE REVIEW 2

2.1 LATHE 2

2.2 SENSORS 3

2.2.1 Temperature Sensors 4

2.2.2 NTC Thermistors: General 5

Properties and Features

2.2.2.1 Temperature Ranges and 5

Resistance Values

2.2.2.2 Accurate and Repeatable 5

R/T Characteristic

2.2.2.3 Sensitivity to Changes in Temperature 6

2.2.2.4 Interchangeability 7

2.2.2.5 Small Size 7

2.2.2.6 Remote Temperature Sensing 7

Capability

2.2.2.7 Ruggedness, Stability & Reliability 7

2.3 TRANSISTOR 8

2.3.1 Importance 82.3.2 Usage 9



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2.4 RECTIFIER 92.4.1 Half-wave rectification 10

2.4.2 Full-wave rectification 11

2.4.3 Peak loss 13

2.5 PRINTED CIRCUIT BOARD (PCB) 14

2.6 RELAY 14

3. PLAN OF WORK 17

3.1 Selection of project 17

3.2 Design and Drawings 17

3.3 Purchase Consideration 17

3.4 Fabrication 17

3.5 Assembly of the parts 18

3.6 Cost Estimation 18

3.7 Report 18

4. MATERIALS AND METHODS 19

4.1 TEMPERATURE SENSOR 19

4.2 AMPLIFIER 20

4.3 COMPARATOR 20

4.4 RELAY 21

4.5 WASHER PUMP 22

4.6 RESERVOIR 22

4.6.1 Design of reservoir 23

4.6.1.1 Design calculations 23

5. DESIGN AND DRAWINGS 24

5.1 FRONT VIEW 24

5.2 SIDE VIEW 25

5.3 TOP VIEW 26



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6 COST ESTIMAION 27

7. RESULTS AND DISCUSSION 29

7.1 OPERATION 29

7.2 BENEFITS OF AN AUTOMATIC COOLING UNIT 29

8. CONCLUSION 30

9. APPENDICES 31

10. REFERENCES 35



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LIST OF TABLES


4.1 Specification for reservoir 22

7.1 Material cost 27

7.2 Labor charge 27

7.3 Other cost 28

7.4 Total cost 28



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LIST OF FIGURES


2.1 Lathe 2

2.2 NTC Thermistor 4

2.3 Comparative resistance graph 6

2.4 Half-wave rectification 10

2.5 Graetz bridge rectifier: a full-wave rectifier

using 4 diodes 112.6 Full-wave rectifier using a center tap

transformer and 2 diodes 11

2.7 Three-phase bridge rectifier 12

2.8 Full-wave rectifier with vacuum tube having

two anodes 12

2.9 Printed Circuit Board 14

2.10 Relay 15

2.11 Relays switch connection 16

4.1 Temperature sensor 19

4.2 bc 547 transistor 20

4.3 LM358 Comparator 20

4.4 Relay 21

4.5 SPST Relay 21

4.6 Washer pump 22

4.7 Reservoir 23

5.1 Front view 24

5.2 Side view 25

5.3 Top view 26

9.1 Washer pump 31

9.2 Circuit 32

9.3 Reservoir 33

9.4 Automatic cooing unit 34



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ABSTRACT

The project is to introduce automatic cooling unit instead of

manual cooling process through design and fabricating the reservoir of the unit.

Automatic cooling unit is a system typically delivers a controlled amount of coolant to

specific locations on a machine while the machine is operating, at specific times from a

central location. when the temperature at the work piece is increased above the reference

temperature, the automatic coolant unit will activate and automatically pumps coolant

and will reduce the temperature.

The temperature sensor or thermistor is placed near to the

tool or work piece, as a result the thermistor senses the temperature from the tool -work

piece interface and sends an electrical signal to the amplifier. The electrical signal is

amplified by using amplifier, then this signal is send to the comparator then the

comparator compares both input and reference signal. If the input signal is greater than

the reference signal then the relay gets activated automatically to control the temperature

to a certain level. So the coolant is pumped from the reservoir to the tool- work piece

interface. Similarly when the temperature decreases below the reference value the control

unit deactivates the pump by using the relay. The process will continue according to the

increase and decrease of the temperature.

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1. INTRODUCTION

1.1 AUTOMATIC COOLING SYSTEM

The long working schedule in the lathe, drilling machine etc...

leads to increase the temperature at the tool as well as the work piece. This high

temperature will affect the tool life and also will affect the surface finish of the work.

So it is very important to introduce automatic cooling system instead of manual

cooling, which will be very useful in the manufacturing industry.

An Automatic coolant unit comprises apump,reservoir,

valvesand control unit. It typically delivers a controlled amount ofcoolant to specific

locations on a machine while the machine is operating, at specific times from a

central location. When the temperature at the work piece is increased above the

reference temperature, the automatic coolant unit will activate and automatically

pumps coolant and will reduce the temperature. So that we can work for longer time

without any interruptions.

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2. LITERATURE REVIEW

2.1 LATHE

Figure 2.1 Lathe

A lathe is a machine tool which rotates the work piece on its axis to

perform various operations such as cutting, sanding, knurling, drilling, or deformation

with tools that are applied to the work piece to create an object which has symmetry

about an axis of rotation.

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Lathes are used in woodturning, metalworking, metal spinning, and

glass working. Lathes can be used to shape pottery, the best-known design being the

potters wheel. Most suitably equipped metalworking lathes can also be used to producemost solids of revolution, plane surfaces and screw threads or helices. Ornamental lathes

can produce three-dimensional solids of incredible complexity. The material can be held

in place by either one or two centers, at least one of which can be moved horizontally to

accommodate varying material lengths. Other work holding methods include clamping

the work about the axis of rotation using a chuck or collet, or to a faceplate, using clamps

or dogs.

Examples of objects that can be produced on a lathe include

candlestick holders, cue sticks, table legs, bowls, baseball bats, musical instruments

(especially woodwind instruments), crankshafts and camshafts.

2.2 SENSORS

All sensors perform the same basic function. They detect a mechanical

condition, chemical state, or temperature conditioning and change it into an electrical

signal that can be used by the microcomputer makes decisions based on information it

receives from sensors. Each sensor used in a particular system has a specific job to do.

Most sensors present in use are available resistors or potentiometers.

They modify a voltage to or from the computer, indicating a constantly changing status

that can be calculated, compensated for, and modified. That is, most sensors control a

voltage signal from the microprocessor. In addition to the variable resisters, two other

commonly used sensors are switches and thermistors. Thermistors are special types of

resistors that convert temperature into voltage.

Even though there are a variety of different sensors designs, they all

fall under one of two operation categories.

1. Reference voltage sensors

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2. Voltage generation sensors.

Reference voltage sensors provide input to the microprocessor by

modifying or controlling a constant, predetermined voltage signal. This signal which can

have a reference value from 5 to 9 volts, is generated and sent out to each sensor by a

reference voltage regulator located inside the processor. Because the processor knows

that certain voltage value has been sent out, it can indirectly interpret things like motion,

temperature, and component position, based on what comes back. Variable resistors,

switches and thermistors are the example of reference voltage sensors.

Voltage generation sensors include components like the hall-effect

switch, oxygen sensor which are capable of producing their own input voltage signal.

2.2.1Temperature Sensors

Temperature sensor detect a temperature conditioning and change it

into electrical signal that can be used by the microcomputer makes decisions based on

information it receives from sensors.

Two common temperature sensing technologies are based on

thermistors or semiconductor junctions.

A thermistor behaves like a resistor whose resistance changes with

temperature. Thermistor is a combination of the words thermal and resistor. The

thermistor was first invented by Samuel Ruben in 1930.

Figure 2.2 NTC Thermistor

Thermistors are available with either positive or negative temperature

coefficients. Positive temperature coefficient (PTC) thermistors have increasing resistance

with increasing temperature. Negative temperature coefficient (NTC) thermistors exhibit

decreasing resistance at increasing temperature. In either case when the current is passedthrough the thermistor, the voltage drop across it is proportional to the temperature

http://en.wikipedia.org/wiki/Image:NTC_bead.jpg


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being sensed. This voltage can then be applied to a simple meter or via an analog-to-

digital converter.

2.2.2 NTC Thermistors: General Properties and Features

NTC thermistors are manufactured in a variety of sizes and

configurations. The thermistor element is usually coated with a phenolic or epoxy

material that provides protection from environmental conditions. For applications

requiring sensing tip dimensions with part to part uniformity and/or smaller size, the

devices can be encapsulated in PVC cups or polyimide tubes.

NTC thermistors offer many desirable features for temperature

measurement and control within their operating temperature range. Although the word

thermistor is derived from THERMally sensitive resISTOR, the NTC thermistor can be

more accurately classified as a ceramic semiconductor. The most prevalent types of

thermistors are glass bead, disc, and chip configurations and the following discussion

focuses primarily on those technologies.

2.2.2.1 Temperature Ranges and Resistance Values

NTC thermistors exhibit a decrease in electrical resistance with

increasing temperature. Depending on the materials and methods of fabrication, they are

generally used in the temperature range of -50C to 150C, and up to 300C for some

glass-encapsulated units. The resistance value of a thermistor is typically referenced at

25C (abbreviated as R25). For most applications, the R25 values are between 100 and

100 k . Other R25 values as low as 10 and as high as 40 M can be produced, andresistance values at temperature points other than 25C can be specified.

2.2.2.2 Accurate and Repeatable R/T Characteristic

The resistance Vs temperature (R/T) characteristics (also known as

R/T curve) of the NTC thermistor forms the "scale" that allows its use as a temperature

sensor. Although this characteristic is a nonlinear, negative exponential function, several



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interpolation equations are available that very accurately describe the R/T curve. The

most well known is the Steinhart-Hart equation: 1/T =A + B (lnR) + C(lnR) 3

Where,

T = Kelvin temperature

R = resistance at temperature T

Coefficients A, B, and C are derived by calibrating at three

temperature points and then solving the three simultaneous equations. The uncertainty

associated with the use of the Steinhart-Hart equation is less than 0.005C for 50C

temperature spans within the 0C-260C range, so using the appropriate interpolation

equation or lookup table in conjunction with a microprocessor can eliminate the potential

nonlinearity problem.

2.2.2.3 Sensitivity to Changes in Temperature

The NTC thermistor's relatively large change in resistance Vs

temperature, typically on the order of -3%/C to -6%/C, provides an order of magnitude

greater sensitivity or signal response than other temperature sensors such as

thermocouples and RTDs. On the other hand, the less sensitive thermocouples and RTDs

are a good choice for applications requiring temperature spans >260C and/or operating

temperatures beyond the limits for thermistors.



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Figure 2.3 Comparative resistance graph

From the graph, over the range of -50C to 150C, NTC

thermistors offer a distinct advantage in sensitivity to temperature changes compared to

other temperature sensors. This graph illustrates the R/T characteristics of some typical

NTC thermistors and platinum RTD

2.2.2.4 Interchangeability

Another important feature of the NTC thermistor is the degree of

interchangeability that can be offered at a relatively low cost, particularly for disc and

chip devices. Interchangeability describes the degree of accuracy or tolerance to which a

thermistor is specified and produced, and is normally expressed as a temperature

tolerance over a temperature range. For example, disc and chip thermistors are

commonly specified to tolerances of 0.1C and 0.2C over the temperature ranges of

0C to 70C and 0C to 100C. Interchangeability helps the systems manufacturer or

thermistor user reduces labor costs by not having to calibrate each instrument/system

with each thermistor during fabrication or while being used in the field. A health care

professional, for instance, can use a thermistor temperature probe on one patient, discard

it, and connect a new probe of the same specifications for use on another patient--without

recalibration. The same holds true for other applications requiring reusable probes.

2.2.2.5 Small Size



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The small dimensions of most bead, disc, and chip thermistors

used for resistance thermometry make for a very rapid response to temperature changes.

This feature is particularly useful for temperature monitoring and control systemsrequiring quick feedback.

2.2.2.6 Remote Temperature Sensing Capability

Thermistors are well suited for sensing temperature at remote

locations via long, two-wire cable because the resistance of the long wires is insignificant

compared to the relatively high resistance of the thermistor.

2.2.2.7 Ruggedness, Stability, and Reliability

As a result of improvements in technology, NTC bead, disc, and

chip thermistor configurations are typically more rugged and better able to handle

mechanical and thermal shock and vibration than other temperature sensors.

2.3 TRANSISTOR

A transistor is a semiconductor device used to amplify and switch

electronic signals. It is made of a solid piece of semiconductor material, with at least three

terminals for connection to an external circuit. A voltage or current applied to one pair of

the transistor's terminals changes the current flowing through another pair of terminals.

Because the controlled (output) power can be much more than the controlling (input)

power, the transistor provides amplification of a signal. Today, some transistors are

packaged individually, but many more are found embedded in integrated circuits.

The transistor is the fundamental building block of modern

electronic devices, and is ubiquitous in modern electronic systems. Following its release in

the early 1950s the transistor revolutionized the field of electronics, and paved the way for

smaller and cheaper radios,calculators, and computers, among other things.

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2.3.1 Importance

The transistor is the key active component in practically all modern

electronics, and is considered by many to be one of the greatest inventions of the twentieth

century. Its importance in today's society rests on its ability to be mass produced using a

highly automated process (semiconductor device fabrication) that achieves astonishingly

low per-transistor costs.

Although several companies each produce over a billion

individually packaged (known as discrete) transistors every year, the vast majority of

transistors now produced are in integrated circuits (often shortened to IC, microchips or

simply chips), along with diodes, resistors, capacitors and other electronic components, to

produce complete electronic circuits. A logic gate consists of up to about twenty

transistors whereas an advanced microprocessor, as of 2011, can use as many as 3 billion

transistors (MOSFETs). "About 60 million transistors were built this year [2002] ... for

[each] man, woman, and child on Earth."

The transistor's low cost, flexibility, and reliability have made it a

ubiquitous device. Transistorized mechatronic circuits have replaced electromechanical

devices in controlling appliances and machinery. It is often easier and cheaper to use a

standard microcontroller and write a computer program to carry out a control function

than to design an equivalent mechanical control function.

2.3.2 Usage

The bipolar junction transistor, or BJT, was the most commonly

used transistor in the 1960s and 70s. Even after MOSFETs became widely available, the

BJT remained the transistor of choice for many analog circuits such as simple amplifiers

because of their greater linearity and ease of manufacture. Desirable properties of

MOSFETs, such as their utility in low-power devices, usually in the CMOS configuration,

allowed them to capture nearly all market share for digital circuits; more recently

MOSFETs have captured most analog and power applications as well, including modern

clocked analog circuits, voltage regulators, amplifiers, power transmitters, motor drivers,

etc.

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2.4 RECTIFIER

A rectifier is an electrical device that converts alternating

current (AC), which periodically reverses direction, to direct current (DC), which is in

only one direction, a process known as rectification. Rectifiers have many uses including

as components ofpower supplies and as detectors ofradio signals. Rectifiers may be made

ofsolid statediodes, vacuum tube diodes, mercury arc valves, and other components.

A device which performs the opposite function (converting DC to

AC) is known as an inverter. When only one diode is used to rectify AC (by blocking the

negative or positive portion of the waveform), the difference between the term diode and

the term rectifier is merely one of usage, i.e., the term rectifier describes a diode that is

being used to convert AC to DC. Almost all rectifiers comprise a number of diodes in a

specific arrangement for more efficiently converting AC to DC than is possible with only

one diode. Before the development of silicon semiconductor rectifiers, vacuum tube diodes

and copper (I) oxide or selenium rectifier stacks were used.

Early radio receivers, called crystal radios, used a "cat's

whisker" of fine wire pressing on a crystal of galena (lead sulfide) to serve as a point-

contact rectifier or "crystal detector". Rectification may occasionally serve in roles other

than to generate direct current per se. For example, in gas heating systems flame

rectification is used to detect presence of flame. Two metal electrodes in the outer layer of

the flame provide a current path, and rectification of an applied alternating voltage will

happen in the plasma, but only while the flame is present to generate it.

2.4.1 Half-wave rectification

In half wave rectification, either the positive or negative half of

the AC wave is passed, while the other half is blocked. Because only one half of the input

waveform reaches the output, it is very inefficient if used for power transfer. Half-wave

rectification can be achieved with a single diode in a one-phase supply, or with three

diodes in a three-phase supply.

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Figure 2.4 Half-wave rectification

The output DC voltage of a half wave rectifier can be calculated

with the following two ideal equations:

V rms = V peak / 2

V dc = V peak/

2.4.2 Full-wave rectification

A full-wave rectifier converts the whole of the input waveform to

one of constant polarity (positive or negative) at its output. Full-wave rectification

converts both polarities of the input waveform to DC (direct current), and is more

efficient. However, in a circuit with a non-center tapped transformer, four diodes are

required instead of the one needed for half-wave rectification. (See semiconductors,

diode). Four diodes arranged this way are called a diode bridge or bridge rectifier.

Figure 2.5 Graetz bridge rectifier: a full-wave rectifier using 4 diodes

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For single-phase AC, if the transformer is center-tapped, then

two diodes back-to-back (i.e. anodes-to-anode or cathode-to-cathode) can form a full-

wave rectifier. Twice as many windings are required on the transformer secondary toobtain the same output voltage compared to the bridge rectifier above.

Figure 2.6 Full-wave rectifier using a center tap transformer and 2 diodes

A very common vacuum tube rectifier configuration contained

one cathode and twin anodes inside a single envelope; in this way, the two diodes required

only one vacuum tube. The 5U4 and 5Y3 were popular examples of this configuration.

Figure 2.7 Three-phase bridge rectifier

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Figure 2.8 Full-wave rectifier with vacuum tube having two anodes

For three-phase AC, six diodes are used. Typically there are

three pairs of diodes, each pair, though, is not the same kind of double diode that would

be used for a full wave single-phase rectifier. Instead the pairs are in series (anode to

cathode). Typically, commercially available double diodes have four terminals so the user

can configure them as single-phase split supply use, for half a bridge, or for three-phase

use.

Most devices that generate alternating current (such devices are

called alternators) generate three-phase AC. For example, an automobile alternator has

six diodes inside it to function as a full-wave rectifier for battery charging applications.

The average and root-mean-square output voltages of an ideal

single phase full wave rectifier can be calculated as:

Where,

Vdc, Vav - the average or DC output voltage,

Vp- the peak value of half wave,

Vrms - the root-mean-square value of output voltage. = ~ 3.14159

2.4.3 Peak loss

An aspect of most rectification is a loss from the peak input

voltage to the peak output voltage, caused by the built-in voltage drop across the diodes

(around 0.7 V for ordinary silicon p-n-junction diodes and 0.3 V for Schottky diodes).

Half-wave rectification and full-wave rectification using two separate secondaries willhave a peak voltage loss of one diode drop. Bridge rectification will have a loss of two

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diode drops. This may represent significant power loss in very low voltage supplies. In

addition, the diodes will not conduct below this voltage, so the circuit is only passing

current through for a portion of each half-cycle, causing short segments of zero voltage toappear between each "hump.

2.5 PRINTED CIRCUIT BOARD (PCB)

A printed circuit board, or PCB, is used to mechanically support

and electrically connect electronic components using conductive pathways, or traces,

etched from copper sheets laminated onto a non-conductive substrate. It is also referred

to as printed wiring board (PWB) or etched wiring board. A PCB populated with

electronic components is a printed circuit assembly (PCA), also known as a printed

circuit board assembly (PCBA).

Figure 2.9 Printed Circuit Board

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PCBs are rugged, inexpensive, and can be highly reliable. They

require much more layout effort and higher initial cost than either wire-wrapped or

point-to-point constructed circuits, but are much cheaper and faster for high-volumeproduction. Much of the electronics industry's PCB design, assembly, and quality control

needs are set by standards that are published by the IPC organization.

2.6 RELAY

A relay is an electrically operated switch. Current flowing

through the coil of the relay creates a magnetic field which attracts a lever and changes

the switch contacts. The coil current can be on or off so relays have two switch positions

and they are double throw (changeover) switches. Relays allow one circuit to switch a

second circuit which can be completely separate from the first. For example a low voltage

battery circuit can use a relay to switch a 230V AC mains circuit. There is no electrical

connection inside the relay between the two circuits; the link is magnetic and mechanical.

The coil of a relay passes a relatively large current, typically

30mA for a 12V relay, but it can be as much as 100mA for relays designed to operate

from lower voltages. Most ICs (chips) cannot provide this current and a transistor is

usually used to amplify the small IC current to the larger value required for the relay coil.

The maximum output current for the popular 555 timer IC is 200mA so these devices can

supply relay coils directly without amplification.

Figure 2.10 Relay

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Relays are usually SPDT or DPDT but they can have many

more sets of switch contacts, for example relays with 4 sets of changeover contacts are

readily available. Most relays are designed for PCB mounting but you can solder wiresdirectly to the pins providing you take care to avoid melting the plastic case of the relay.

The animated picture shows a working relay with its coil and switch contacts. You can see

a lever on the left being attracted by magnetism when the coil is switched on. This lever

moves the switch contacts. There is one set of contacts (SPDT) in the foreground and

another behind them, making the relay DPDT.

Figure 2.11 Relays switch connection

The relay's switch connections are usually labeled COM, NC and NO:

COM = Common, always connect to this; it is the moving part of the switch.

NC = Normally Closed, COM is connected to this when the relay coil is off.

NO = Normally Open, COM is connected to this when the relay coil is on.



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3. PLAN OF WORK

Planning is an important part of every project. Nobody plans to

fail, but they fail to plan. So before staring our project work we made some planning for

the successful completion of the project.

3.1 SELECTION OF PROJECT

By considering the benefits of the project with the present

conditions, the amount of money can be invested, availability of the material, duration of

project, design and fabrication area the project can be planned.

3.2 DESIGN AND DRAWINGS

Having been decided about the project to be manufactured, it

must be designed. The work of the design should be done very carefully by considering all

the relevant factors. After designing the project its detailed drawing are prepared so that

no doubts are left for future, detailed specifications of raw materials and finished

products should be decided carefully along with the specification of the machine required

for their manufacture.



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3.3 PURCHASE CONSIDERATION

It is very difficult to fabricate each and every components of the

project. Fabrication must be based on the accuracy that can be obtained from the

components. If the project have some electronic components, then it is better to buy the

components from the market, and assemble it to the requirement.

3.4 FABRICATION

Fabrication of the components can be done with the help of

designed calculations and drawings through different manufacturing process like cutting,

welding, drilling etc

3.5 ASSEMBLY OF THE PARTS

The fabricated and purchased components are assembled

together to complete the fabrication process.

3.6 COST ESTIMATION

Cost estimation can be calculated by considering the material

cost, labor cost, transportation charges etc...

1. Material cost

2. Labor cost

3. Transportation expenses

3.7 REPORT

At the end of the project work, a report is prepared for future

references. The project report consists of all the items done during the project work.



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4. MATERIALS AND METHODS

4.1 TEMPERATURE SENSOR

The Sensor used for the temperature measurement is

thermistor. Temperature sensor detect a temperature conditioning and change it intoelectrical signal that can be used by the microcomputer makes decisions based on

information it receives from sensors.

Name : Thermistor

Type : NTC Thermistor

Temperature range : -50C to 150C

Resistance tolerances : 2%

Overall lengths : 18mm- 78mm

Figure 4.1 Temperature sensor



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4.2 AMPLIFIER

Amplifier is any device that will convert one signal often with

a small Amount of energy into another signal often with a larger amount of energy. In

automatic coolant unit the electrical signal from the thermistor is amplified by using

amplifier.

Figure 4.2 bc 547 transistor

4.3 COMPARATOR

The comparator is used to compare the amplified electrical

signal from the amplifier to the comparator with the reference signal.



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Figure 4.3 LM358 Comparator

4.4 RELAY

A relay is an electrically operated switch. Current flowing through

the coil of the relay creates a magnetic field which attracts a lever and changes the switch

contacts. The coil current can be on or off so relays have two switch positions and they

are double throw (changeover) switches. Relays allow one circuit to switch a second

circuit which can be completely separate from the first.

Figure 4.4 Relay



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Figure 4.5 SPST Relay

4.5 WASHER PUMP

Washer pump, various style12Vwindscreenwasher pumps,pumps for the transfer of water from reservoir to the specific location through nozzles.

Figure 4.6 Washer pump

4.6 RESERVOIR



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Reservoir is the storage area for the coolant and the coolant is

supplied to the specific location from the reservoir with the help of pump.

Sl.

No

SPECIFICATION

1 Material Sheet metal

2 Length 30cm

3 Breadth 20cm

4 Height 17cm

5 Nozzle diameter 1.2cm

Table 4.1 Specification for reservoir

4.6.1 Design of reservoir

Figure 4.7 Reservoir



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4.6.1.1 Design calculations

( i ) Volume ( V ) =l*b*h

=30*20*17=10200 cm3

5. DESIGN & DRAWINGS

5.1 FRONT VIEW



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Figure 5.1 Front view

5.2 SIDE VIEW



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Figure 5.2 Side view

5.3 TOP VIEW



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Figure 5.3 Top view

6. COST ESTIMAION



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MATERIAL COST

Sl.

NoMATERIAL COST COST

1 Metal Sheet 200

2 Electronic devices 300

3 Washer pump 200

TOTAL 700

Table 7.1 Material cost

LABOR CHARGE

Sl.

NoLABOR CHARGE COST

1 Gas cutting 100

2 Welding 200

3 Drilling 25

4 Other operations 50

TOTAL 375

Table 7.2 Labor charge

OTHER COST

Sl.

No

OTHER COST COST

1 Transportation charges 50

2 Paintings 30



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TOTAL 80

Table 7.3 Other cost

TOTAL COST

Sl.

NoTOTAL COST COST

1 Material costs 700

2 Labor charges 375

3 Other costs 80

TOTAL 1155

Table 7.4 Total cost

7. RESULT AND DISCUSSIONReservoir has been fabricated successfully as designed and also

assembled the components such as temperature sensor, amplifier, comparator, and relay

in the PCB board to full fill the requirements of complete operation of the automatic

cooling unit.

7.1 OPERATION

a) The temperature sensor or thermistor is placed near to the tool or work piece.



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b) The thermistor senses the temperature from the tool or work piece and sends an

electrical signal to the amplifier.

c) The electrical signal is amplified by using amplifier, then this signal is send to the

comparator then the comparator compares both input and reference signal.

d) If the input signal is greater than the reference signal then the relay gets activated

automatically to control the temperature to a certain level

e) The drive pumps the lubricant or coolant from the reservoir to the tool- work piece

interface.

f) Similarly when the temperature decreases below the reference value the control unit

deactivates the pump by using the relay.

g) The process will continue according to the increase and decrease of the temperature.

7.2 BENEFITS OF THE AUTOMATIC COOLING UNIT

Automatic cooling unit have many advantages over traditional methods of manual cooling

process:

a) The process is an automatic with the increase in temperature.

b) Cooling occurs while the machinery is in operation.

c) Proper cooling ensures safe operation of the machinery.

d) Extended tool life, fewer breakdowns, reduced downtime, reduced replacement

costs, reduced maintenance costs and good surface finish.

e) Measured cooling means no wasted coolant.

f) Lower power consumption.

8. CONCLUSION

The automatic cooling unit has been successfully introduced instead of

manual cooling process by design and fabricating the components of the unit.

As temperature in the tool- work piece interface comes above the

reference temperature, the unit successfully activated and reduced the temperature.

Similarly, as the temperature comes below the reference temperature, the unit gets

deactivated successfully.

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9. APPENDICES



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PHOTOGRAPHY



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Figure 9.1 Washer pump



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Figure 9.2 Circuit



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Figure 9.3 Reservoir



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Figure 9.4 Automatic cooling unit



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10. REFERENCES

Books1. Manufacturing Technology II, G.K. Vijayaraghavan, A.R.S. Publications, fifth edition,

nov 2009

2. Electronics and Microprocessors, V. Thiyagarajan, A.R. Publications, fourth edition,

dec 2008

3. Automobile Engineering, G.K. Vijayaraghavan, A.R.S. Publications, fifth edition, nov

2010

Websites1. Automatic cooling system,www.koolmist.com/automatic_cooling_unit

2. BTS Room Automatic cooling unit FCU, www.damcon.com.pk/proinfo.php

3. Automatic air cooling unit, www.prodeco/srl.com/eng/accessori.html

4. Wikipedia , www.wikipedia.com/automaticlubrication
http://www.koolmist.com/automatic_cooling_unithttp://www.koolmist.com/automatic_cooling_unithttp://www.damcon.com.pk/proinfo.phphttp://www.wikipedia.com/automatichttp://www.koolmist.com/automatic_cooling_unithttp://www.damcon.com.pk/proinfo.phphttp://www.wikipedia.com/automatic

automatic cooling system

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