DESIGN AND FABRICATE BRAKING SYSTEM FOR THE ELECTRIC BUGGY CAR
MUHAMMAD BIN ZULKIFLY A report submitted in partial fulfillment of the requirements for the award of the degree of Bachelor of Mechanical Engineering
Faculty of Mechanical Engineering
Universiti Malaysia Pahang
NOVEMBER 2007
A
ABSTRACT
Nowadays, brake system is probably the most important system for vehicle.
Most buggy cars have disc brakes on the rear wheels, and some have disc brakes on
all four wheels. This is the part of the brake system that does the actual work of
stopping the car. The main thing in the braking system is caliper, master cylinder,
disc brake or rotor and the hose or piping. Research and comparison are done to
make sure the flow of the project run smoothly. To design the suitable breaking
system for Electric Buggy Car must depend on the speed the vehicle, maximum
weight of baggage and weight driver and body. From the research that we get from
the design before, for suitable these Electric Buggy Car breaking system to use is
motorcycle RXZ/TZM breaking systems or Go Kart breaking system. The
Motorcycle and Go Kart breaking system is simple and efficient for the Electric
Buggy Car and easy to maintenance the brake and not complicated system. In this
Electric Buggy Car we selected to use the motorcycle Yamaha 125Z Braking system
because of the low cost of the part compared with the Go Kart Braking System. The
most of the problem in this project is selected of the push rod because of the material
cannot withstand the high force when the brake is applied. To overcome the trouble,
modification and testing is the process of the recovered. Finally, the Braking System
for the Electric Buggy Car can functionally with the best performance.
vi'
ABSTRAK
Pada masa sekarang, perkembangan dunia automotif adalah semakin
berkembang pesat. Sebagai contoh dalam pembinaan rekabentuk Buggy Car itu
sendiri kebanyakkannya telahpun mula menggunakan system brake disc terutama
sekali diletakkan di bahagian belakang kenderaan tersebut dan ada juga mempunyai
system brake disc di kedua-dua belah bahagian depan dan belakang kereta tersebut.
Fungsi utama kegunaan system brake itu sendiri tentunya adalah untuk
memberhentikan kenderaan itu sendiri. Komponen utama dalam pembentukan
system brake itu mestilah mempunyai Caliper Brake, Master Cylinder, Disc Brake
atau Rotor, system piping atau hose dan juga pedal. Didalam pembinaan system
brake bagi kenderaan mi adalah semestinya bergantung kepada kelajuan maksima
yang boleh dicapai oleh kenderaan tersebut, berat maksima kenderaan tersebut
bersama-sama pemandu dan penumpang serta berat maksima muatan yang boleh
ditampung dan dibawa. Daripada kajian yang telah dijalankan, system brake yang
bersesuaian bagi kenderaan Buggy Car mi adalah menggunakan system brake
daripada Yamaha 125Z. Sistem braking motosikal adalah yang terbaik , mudah dan
senang dalam melakukan kerja penyelenggaraan , efficient dan system brake tersebut
adalah tidak terlalu rumit untuk di rekabentuk kepada keadaan rekabentuk Buggy Car
tersebut. Selain daripada iii, juga,dari segi aspek kos dalam mendapatkan spare part
untuk braking sistem juga adalah rendah dan mudah didapati jika di bandingkan
dengan braking sistem yang lain. Dalam pembinaan projek mi masalah utama yang
telah dihadapi adalah bar ataupun palang untuic menekan atau mengepam master
cylinder yang path awal penggunaannya adalah tidak tahan kepada daya yang tinggi
apabila pedal ditekan. Dalam mengatasi masalah ini,pengubahsuain pada bar
ataupun palang sering dibuat mengikut ketahanan dan kesesujan supaya masalah
dapat diatasi. Pada akhirnya, keberkesanan dan fungsi system brake tersebut telah
dapat mencapai tahap keberkesanannya.
TABLE OF CONTENTS
CHAPTER
TITLE
ACKNOWLEDGEMENT
ABSTRACT
ABSTRAK
LIST OF FIGURES
LIST OF TABLES
LIST OF CHART
PAGE
VI
VII
VIII
XII
XV
XVI
INTRODUCTION
2
1.1
Project background
I
1.2
Objectives
2
1.3
Scopes of project
2
LITERATURE REVIEW
2.1
History of Disc Brake
3
2.2
Introduction of Disc Brake
5
2.3
Basic Brake System
6
2.4
The Operation of The System
7
2.5
Hydraulic Principle
8
2.5.1
Liquid will not compress
9
2.5.2
Air will compress
9
2.5.3
Force and Pressure
10
ix
2.6
Basic principle of a hydraulic brake system
11
2.7
Master Cylinder
12
2.7.1
12
2.8
2.9
The Operation of Master Cylinder
Caliper
13
2.8.1
Fixed Caliper
14
2.8.2
Floating Calipers
14
Brake Disc
15
2.9.1
16
Features of disc brake
2.10
Disc Pads
17
2.11
Tubing and Hose
18
2.12
Brake Fluid
21
2.13
Brake Lining
22
2.14
Gas Metal Arc Weld
24
2.15
Product Development Process
26
2.16
Product Development Process for Proposed
Braking System for Electric Buggy Car
27
2.17
Requirement Definition
27
2.18
Conceptual Design
28
2.19
Detail Design
28
2.20
Test and Evaluation
29
2.21
Manufacturing
30
2.22
Logistic, Supply Chain and Environment
30
3
METHODOLOGY
3.1
Introduction
32
3.2
The Methodology
33
3.3
Literature review
33
3.4
Proposed design
34
3.4.1
Preliminary design
34
3.4.2
Detail design
34
3.5
Fabrication
35
3.6
Test run
38
3.7
Result and Analysis
39
x
3.8
Final Report
39
3.9
Flow Chart
40
4-
RESULT AND DISCUSSION
4.1
Overview
41
4.2
Finish Product
42
4.2.1
42
Result
4.3
Observation and Analysis
43
4.4
Brake Analysis
44
4.4.1
Drive Ratio
44
4.4.2
Strength of the material
45
4.4.3
Maximum heat dissipation of brake
46
4.4.4
Minimum Braking Time and Distance
47
4.5
Problem and Solution
49
CONCLUSION
5.1
Conclusion
50
5.2
Recommendation
51
5.2.1
Disc Plate
51
5.2.2
Push Rod
52
5.2.3
Caliper Situate
52
REFERENCE
APPENDIX
54
xi
LIST OF FIGURE
FIGURE NO.
TITLE
2.1
Basic operation of breaking system
2.2
Fluid transmit pressure equally throughout a hydraulic
PAGE
7
Circuit and act with an equal force on each surface of the
same size
8
2.3
Force applied to a liquid transmit the pressure
9
2.4
Force applied to the piston compressed the air not liquid
10
2.5
Force transmitted by hydraulic means from one cylinder
10
to another
2.6
Basic principle of a hydraulic brake system
11
2.7
Basic master cylinder
13
2.8
Fixed Calipers
14
2.9
Floating Caliper
15
2.10
Dics brake
17
2.11
Section of a disc and caliper showing the cylinder, pistons
17
and pad
2.12
Disc brake pads
17
2.13
Flexible rubber hose
18
2.14
Hydraulic hose and tubing
19
2.15
Quality brake tubing is made by a wrapping a strip of steel
19
2.16
The most common cause of hose failure are shown above
20
2.17
Shows the dry and wet boiling point for several brake fluid
22
2.18
Brake Lining
23
2.19
Basic equipment in GMAW operations
25
2.20
GMAW Process
26
3.1
Final Design of Bubby Car and Assembly with Braking System
Frame Works
3.2
.
35
36
xl'
3.3
Caliper Braking System assembly 36
3.4
Pedal assembly with Frame 37
3.5
Master Cylinder connected with push rod and the state of
Hydraulic trace oil
37
3.6
Pedal connected with push rod and the stopper 38
3.7
Project Flow chart
40
4.1
Part of the Braking System to the frame 42
4.2
ETEK Motor D.0
43
Appendix A
Complete Fabrication Process
5.1
Isometric view Buggy Car and Braking Assembly 5.2
Side view and braking assembly with pedal, push rod, hose,
54
Master cylinder, plate disc and caliper
54
5.3
Back View Caliper and plate disc with hose
55
5.4
Side View and Caliper with Brake disc 55
Appendix B-
Technical Drawing
5.5
Isometric View from Solid work
56
5.6
Top View from Solid work
56
5.7
Back View from Solid work
57
5.8
Side view from Solid work
57
5.9
Front View from Solid work
58
5.10
Master Cylinder drawing
59
5.11
Brake Disc drawing
59
5.12
Connector drawing
60
5.13
Brake Fluid Trace drawing
60
5.14
Hose drawing
61
5.15
Brake Pedal drawing
61
5.16
Caliper Brake Disc drawing
62
xlii
Appendix C
Detail Drawing
5.17
Buggy Car Assembly
63
5.18
Frame Structure
64
5.19
Pedal Brake detail drawing
65
5.20
Push Rod detail drawing
66
5.21
Hose detail drawing
67
5.22
Brake Disc detail drawing
68
5.23
Brake Fluid Trace detail drawing
69
5.24
Master Cylinder detail drawing
70
5.25
Connector detail drawing
71
5.26
Caliper Brake disc detail drawing
72
xiv
LIST OF TABLE
TABLE
2.1
TITLE
The dry and wet boiling point requirement of DOT 3,4
PAGE
21
and 5 brake fluid
2.2
Shows the operating characteristic for the three organic 23
and four metallic lining types
2.3
Some of the advantages and disadvantage of different lining type
24
5.1
Gantt Chart for PSM 1
73
5.2
Gantt Chart for PSM 2
74
CHAPTER 1
INTRODUCTION
1.0
Project Background
Nowadays Electric Buggy Car at airport is popular around the world using for
carry all the passenger baggage. People use the buggy car is using for caring
something that the people can handle or bring uses their hand.
The brake system is probably the most important system for vehicle. Most
buggy cars have disc brakes on the rear wheels, and some have disc brakes on all
four wheels. This is the part of the brake system that does the actual work of
stopping the car.
There are two design of break disc is solid disc and ventilated disc. Brake
disc make from cast iron, with a ground surface on each side against which the pads
are applied. The disc is shaped to fit over the wheel hub and has a drilled hole to fit
the wheel studs. To design the suitable breaking system for Electric Buggy Car must
depend on the speed the vehicle, maximum weight of baggage and weight driver and
body.
For suitable these Electric Buggy Car breaking system to use is motorcycle
RXZ/TZM breaking systems or Go Kart breaking system. The motorcycle and Go
Kart breaking system is simple and efficient for the Electric Buggy Car and easy to
maintenance the break and not complicated system. The break disc system use
hydraulic oil to transmit force and also increase the force. The breaking system
PA
operated with fluid (oil). Hydraulics is part of the more general discipline of fluid
power to function the breaking system.
1.2
Project Objective
To design the breaking system for Electric Buggy Car
To fabricate the breaking system
1.3
Scopes Of Project
• Research on Hydraulic Break Disc System conducted to collect
information as required in literature review.
• Use motorcycle breaking system (YAMAHA 125Z) or Go Kart Breaking System to appropriate for the design of Buggy Car.
• Analyze the efficiency / function the Breaking System from the ETEK
motor 24-48 Volt D.C.
• Develop the suitable breaking system for Buggy Car using motorcycle
or go kart braking system.
• Design and fabricate the breaking system from pedal to break disc
depend on the frame structure.
• Low cost for the design of the Braking System.
CHAPTER 2
LITERATURE REVIEW
2.1 HISTORY OF DISC BRAKE
As the level of technology of transportation has increased, the mechanical
devices used to slow down and stop vehicles has also become more complex. The
history of vehicular braking technology and possible future developments.
Before there was a "horse-less carriage," wagons, and other animal drawn
vehicles relied on the animal's power to both accelerate and decelerate the vehicle.
Eventually there was the development of supplemental braking systems consisting of
a hand lever to push a wooden friction pad directly against the metal tread of the
wheels. In wet conditions these crude brakes would lose any effectiveness.
In this chaotic era is the first record of the disk brake. Dr. F.W. Lanchester
patented a design for a disk brake in 1902 in England. It was incorporated into the
Lanchester car produced between 1906 through 1914. These early disk brakes were
not as effective at stopping as the contemporary drum brakes of that time and were
soon forgotten. Another important development occurred in the 1920's when drum
brakes were used at all four wheels instead of a single brake to halt only the back
axle and wheels such as on the Ford model T. The disk brake was again utilized
during World War II in the landing gear of aircraft. The aircraft disk brake system
was adapted for use in automotive applications, first in racing in 1952, then in
production automobiles in 1956. United States auto manufacturers did not start to
4
incorporate disk brakes in lower priced non-high-performance cars until the late
1960's.
Early disk brake systems required an outside mechanical brake booster such
as a vacuum assist or hydraulic pump to generate the pressure for primitive friction
materials to apply the necessary braking force.
A recent Ducati concept show bike uses brake disks of silesium, developed
by the Russian aerospace industry(3), which claim to have the friction coefficient of
cast iron with the light weight of carbon fiber.
5
2.2
Introduction of Breaking System
The breaking system provides the means to stop or slow the vehicle. To
control for the vehicle, we need to be able to start it moving, make it turn, accelerate
and decelerate and of the major importance to stop it. A vehicle with a breaking
system that is not working properly is a candidate for the wreaking yard and may be
cause injury to the driver and passenger as well as to others.
The breaking system is considered by many people to be the most important
system involved in the operation of the vehicle. We do not normally use brakes at
their maximum capability, but we want the system to work flawlessly in emergency
much like parachute. Most of user find hard breaking unpleasant and avoid hard
stops. The breaking system of most vehicle are rarely tested ensure that they are
working at minimum efficiency.
The ideal breaking system is one of that will allow the driver to bring a
vehicle to a stop in the shortest possible distance. To be able to do this, it should
have an enough power to lock up and skid all tires while stopping on clean, dry
pavement. Also, stopping should occur with a moderate amount of pedal pressure so
that even weaker drivers can achieve tire lockup.
No legislation specifies exactly what to do, and there are no commonly used
test devices or instruments to access exactly how good or bad a brake system is.
2.3 Basic Brake System
The parts are as follow:-
1. Brake Pedal
- Operated by the driver.
2. Brake booster
- Provides the brake easier to apply
3. Master cylinder
- Provides hydraulic pressure
4. Caliper and Disc
- Slow or stop the wheels when the brake calipers at
the wheel.
5. Brake lines and Hoses - Connect the master cylinder to the caliper at the
wheels
6. Brake Fluid
- Transmits force from the master cylinder to the
calipers at the wheels.
7. Connector Rod
- Connected from brake pedal until master cylinder to
transmit the pressure when pedal is apply.
7
2.4 The Basic Operation of the System
When the driver pushes the brake pedal fro the figure 2. 1, force will be
transmitted to the piston in the master cylinder. The pistons will apply the pressure
to the fluid in the cylinder and the brake lines transfer the pressure to the caliper.
The pistons in the hydraulic cylinder in the caliper are move to apply the brakes.
When disc brake is applied, brake pad is clamped against the disc. A moving
vehicle has energy, which must be absorbed by the brakes when they are applied.
The energy is converted into heat as a result of the friction between the breaking
surfaces. The heat is then dissipated into the brake parts and into the surrounding
atmosphere. Therefore, the brake pad and disc or the brake lining, the material must
be withstood high temperature as well as high pressure.
caliper
caliper
Figure 2.1 Basic operation of breaking system
8
2.5
Hydraulic Principle
The hydraulic system (Fluid Power) is a method of transmitting the motion or
force. It does this by having a cylinder and piston in a different sizes. Hydraulic is
based on the fact that liquid can flow easily through complicated path, yet cannot be
compressed. Another important feature is that when liquid transmit pressure, that
pressure will be transmitted equally in all direction. This is known as Pascal's
Principle. The figure 2.2 had shown the basic of Pascal's Principle.
Figure 2.2 Fluid transmit pressure equally throughout a hydraulic circuit and act with an equal force on each surface of the same size.
2.5.1 Liquid will not compress
For all practical purpose, liquids are not compressible and so hydraulic
pressure represents a pressure applied to the liquid. It does not mean that the liquid
is reduced in volume, as is the case with a gas. Refer to cylinder in figure 2.3 which
contains liquid and a piston. As a result of the force on the piston, the liquid applies
pressure to the walls and the bottom of the cylinder. From the figure 2.3 the piston
does not move because there is nowhere for the liquid to go.
Figure 2.3 Force applied to a liquid transmit the pressure
2.5.2 Air will compress
If the cylinder contains both air and liquid, a force applied to the piston will
compress the air and reduced its volume and the piston will move down the cylinder
(Figure 2.4). When the force is removed, the piston will return to its original
position.
10
Figure 2.4 Force applied to the piston compressed the air not liquid
2.5.3 Force and Pressure
Figure 2.5 shows the 2 cylinder of the same size (diameter). Forced applied
to one piston is being transfer hydraulically to the other. Because the cylinder and
the piston are the same size, the force applied to one piston will be the same as the
forced delivered by the other. However, by having cylinders of different size, force
can be increased or reduced.
Figure 2.5
Force transmitted by hydraulic means from one cylinder to another.
11
2.6
Basic principle of a hydraulic brake system
Figure 2.6 is a simple hydraulic brake system with three cylinders of different
size. The diagram can be used to explain force and pressure.
0
When the pedal is pressed, the force against the piston in the master cylinder
(A) will apply pressure to the fluid. The pressure will be the same in all part of the
system, but will have a different effect on the piston in the other cylinder. There will
be different forces from the piston as follows:
1. Cylinder (B) is smaller than (A), so the force from (B) will be less than the
force applied to (A).
2. Cylinder (C) is larger than (A), so the force from its piston will be greater
than the force applied to (A).
In an actual hydraulic brake system, the master cylinder is smaller than the
wheel cylinder, so the force all the wheel cylinder is increased. The force can be
varied by the use of different sized cylinder and it can be varied from front to rear to
provide better breaking. This can be done even though the pressure is same in all
part of the System.
12
2.7 Master Cylinder
The figure 2.7 is shown the basic operational of master cylinder. The master
cylinder is the input piston for the vehicle break system. It is connected to the break
pedal so the movement of the break pedal is transmitted to the master cylinder piston
by a pushrod. The first master cylinder used a single piston and cylinder bore with
one outlet at the end of the bore. From this outlet, tubing branched out to each of the
wheel cylinder.
The master cylinder body has two major areas, the piston and the cylinder
bore and the reservoir. These two areas are connected by two passages, a small
compensating port and a larger bypass port (intake or replenishing port).
2.7.1 The Operation of Master Cylinder
1. When the break applied, the primary piston is moved in its bore and fluid is
displaced by the piston.
2. Because of its larger bore, there will be more fluid displaced by the rear part of
the primary piston than by the front.
3. This is can be produced a high volume of fluid, which quickly moves the brake
Pad to take up the clearance between them and the disc.
4. With continued movement of the piston, pressure builds up in the system ahead
of the piston to apply the breaks.
5. This is also some pressure created in the large bore behind of the head of piston.
This pressure opens the ball in the fast fill valve so that fluid can flow from the
large bore back into the reservoir.
6. Once the fast fill valve has opened, the cylinder acts in the same way as a
c onventional master cylinder, with all the pressure being created in the small bore
section of the master cylinder.
13
compensating port
return Spring
inlet port
I
check
valve
Figure 2.7 Basic master cylinders
2.8
Caliper
The two major style of caliper are used on vehicle:1. Fixed Caliper
2. Floating Caliper
Most caliper use a cup shaped bore in a cast iron caliper body. Each bore will
include a piston with a seal and boot, and a bleeder screw. A few pistons include an
insulator to block heat flow from the lining to the piston. Disc brake experienced
higher brake fluid operating temperature because the fluid in the caliper body is
fairly close to the friction material, and the caliper body and piston conduct quite a
bit of heat to the fluid.
14
2.8.1 Faxed Caliper
A fixed caliper assembly and a solid disc are illustrated in figure 2.8. Two
piece calipers are used, with two parts being bolted together. The caliper has two
cylinders, one on each side of the disc, and so each piston operates its own brake pad.
When the brakes applied, hydraulic pressure is applied to the piston and the piston
and they move the pads against the disc equal force.
Figure 2.8 Fixed Calipers
2.8.2 Floating Calipers.
The dismantled part of the floating caliper assembly is shown in figure 2.9.
The main parts of the assembly are the caliper housing, the anchor plate, the piston
and the pads. This type of the caliper is made as single part and has only one
cylinder, which is built into the inner side of caliper.