Electronically Controlled Adjustable Supercharger

Department of Mechanical and Materials Engineering
Florida International University, Miami, FL
EML 4551
A SENIOR DESIGN PROJECT
PREPARED IN PARTIAL FULFILLMENT OF
THE REQUIREMENT OF
THE DEGREE OF BACHELOR OF SCIENCE IN
MECHANICAL ENGINEERING
Magnetically Controlled
Adjustable Supercharger System
for
Internal Combustion Engines
Submitted by:
Mechanical Engineering Group:
Richard A. Castillo, 1394908
Juan Saluzzio, 1372735
Paul Grata, FIU ME Graduate
Electrical and Computer Engineering Group:
Ajay Matthews, 1673356
Andres Bayon, 1306782
Ryan Bareno, 1794247
Daniel Jimenez, 1038149
December 5th, 2007
Faculty Advisor
X_______________________
Prof. Sabri Tosunoglu, PhD.
This report is written in partial fulfillment of the requirements in EML-4905. The contents represent the opinion of
the authors and not the Department of Mechanical & Materials Engineering
Design Team and Advisors
Team Members
Title
Signature
Richard A. Castillo
Chief Designer, Project Leader
Mechanical & Materials Engineering
CGS Engineering
Juan Saluzzio
Manufacturing Engineer
Mechanical & Materials Engineering
CGS Engineering
________________
Paul Grata
Machining Specialist
Design Engineer
Mechanical & Materials Engineering
CGS Engineering
________________
Ajay Matthews
Project Leader , EE Group
Design Engineer
Electrical Engineering Dept.
Polarized Engineering
________________
Danny Jimenez
Quality and Testing Engineer
Electrical Engineering Dept.
Polarized Engineering
________________
Ryan Bareno
Research & Design Coordinator
Electrical Engineering Dept.
Polarized Engineering
________________
Andres Bayon
Chief Programming Engineer
Electrical and Computer Engineering
Polarized Engineering
________________
Advisors/Consultants
Principal Investigator
Sabri Tosunoglu, PhD.
Mechanical Engineer
Automation, Mechanics, Systems Control
Mechanical and Materials Engineering
Stavros V. Georgakopoulos, PhD.
Electrical Engineer
Communications, Hybrid Antennas
Electrical and Computer Engineering
2
Acknowledgements
The authors of this report deeply appreciate the help and support received from numerous
students, faculty and members of industry. First off, we like to extend our many thanks to Eaton
Corporation, specifically to sales engineer Kaid A. Cousineau, who sponsored us with the most
important component used in this project.
We cannot continue without thanking Richard Zicarelli from the Manufacturing Research Center
over at Industrial Engineering. His resourcefulness and skills as an industrial machinist were
invaluable to our project. We cherish his candor and patience in working with our group
considering the difficulties and intricacies of our peculiar machining requests. Within our
Mechanical and Materials Engineering Department, we would like to extend our gratitude and
never ending thanks to our mentor, Professor Sabri Tosunoglu. As always, he believed in our
skills and our knowledge for bringing this project to life and for his advice, he is always there for
us. I also thank our student colleagues from the Electrical and Computer Engineering
Department for their unwilling compromise to work with us in this project. Continuing with our
thanks, our most sincere and utmost gratitude to the Supervisor and Director of the Advanced
Materials Engineering Research Institute (AMERI) for their understanding and never ending
support throughout this period, Neal P. Ricks and Professor W. Kinzy Jones PhD.
Finally, without further a due, we need to express our sincere and most profound appreciation to
our closest family members who endured this process alongside with us. It is their remarkable
contribution to our well being that made this endeavor possible. Without them, we would not be
here today.
In short, we thank you all for your help!
Richard A. Castillo
Senior Design Project Leader
Mechanical and Materials Engineering Department
CGS Engineering Group
3
Front matter:
Student Teamwork Statement:
As a multidisciplinary team members of the “Magnetically Controlled Adjustable Supercharger
System for Internal Combustion Engines” design team, we have taken an oath to work together
towards the goal of designing and building this project to the best of our abilities. As members of
different engineering disciplines, are aware of our distinct responsibilities, and have worked
together dedicated to the completion of this capstone project to partially fulfill our requirements
for graduation within our respective engineering disciplines.
4
Ethical Design Statement
During the conceptual, design and building stages of our project, we have conformed to the Code
of Ethics provided by the National Society of Professional Engineers (NSPE). Though this
system is only a prototype, we have met various safety guidelines as to its operation and testing.
Though the purpose of this particular device is to be implemented in an automobile, our
prototype has not been designed for such. At this time, this design is not going to be tested in real
life conditions however we have made sure that any person using this equipment for
demonstration or testing purposes will be safe at any moment.
As future professional engineers, we have made sure that safety becomes a principal factor
within our design, not only for the safety and well being of the individual and the public which
could potentially use this design, but for its structural sanity as well as integrity.
Environmental Impact Statement
The entire project consisting of the clutch/coupler mechanism, electronics and industrial grade
components have been carefully chosen for their environmental impact. None of the materials
chosen are harmful to the environment if carefully handled. Since there are no materials that will
need replacement nor repair, the actual maintenance on such system is considered to be at a
minimum. If any component should need replacement, then the proper method of disposing or
recycling such component(s) will be considered.
5
ABSTRACT
The primary objective of this project is to implement a method of engaging a supercharger
assembly to an internal combustion engine by means of a frictionless, magnetically driven
engagement system. This system will offer a more controlled method of providing additional
power and efficiency to an internal combustion engine by variably controlling its engagement
with the engine.
A secondary objective of this project is to provide a different means of transferring torque from
different drive components used in the automotive industry.
The actual system involves the clutch system which consists of an aluminum hub machined in
such a way to hold a fixed amount of magnets arranged in an array with their polarities
interchanged throughout. This hub is held in place with a linear bearing that slide on a splined
shaft. This hub will rotate and at the same time have linear motion; this is to help in the
engagement of the clutch. On the opposite side, we have a copper alloy plate with the
corresponding bearings and pulleys that will be attached through a serpentine belt to the
supercharger. This hub/plate clutch will be engaged with the help of a linear actuator, custom
made linkage system and it will be controlled with a custom made, control unit designed by the
electrical engineering department group. This unit will take into account the speed of the
hub/plate, motor speed, pressure and flow of the supercharger, and throttle position in order to
appropriately engage/disengage the clutch system.
Upon completion of this project, and in conjunction with the Office of Sponsored Research
Administration at Florida International University, the process of patent application will
commence given that this technology has not been yet exploited for automotive applications. We
have hope that our idea and application of such device to the automotive industry, will prove it’s
economic and market profitability and eventually be part of everyday, internal combustion
engine technology in order to increase their efficiency and functionality. By doing so, we
inherently decrease the environmental impact or “Carbon Footprint” internal combustion engines
make throughout their operation.
6
TABLE OF CONTENTS
List of Figures and Tables
1
CHAPTER 1. INTRODUCTION
1.1
Background Information
2
1.2
Current Technology
3
1.3
Related Engineering Topics
4
CHAPTER 2. DESIGN CONCEPT
2.1
Goal Statement
5
2.2
Objectives
6
2.3
Form and Functionality
7
2.4
Constraints and Challenges
8
2.4
Target Clientele/Industry
8
2.5
Design Specifications
9
2.5
Functional Analysis
10
CHAPTER 3. SOLID MODELING
11
3.1
Concept
12
3.2
Drawing Generations
10
3.3
Engineering drawings
13
CHAPTER 4. ENGINEERING ANALYSIS
4.1
Overview of System
14
4.2
Magnet Assembly
15
4.2.1
Mechanical Analysis
16
4.2.2
Magnetic Analysis
17
4.3
Shaft/Bearing Assembly
18
4.3.1
19
Mechanical Analysis
7
4.4
4.5
4.6
4.7
Actuator and Linkage Assembly
4.4.1
Mechanical Analysis
20
4.4.2
Electronic Schematic and Analysis
21
Motor and Electronic Control Unit
22
4.5.1
Overview of control unit
23
4.5.2
Electronic Schematics
24
Supercharger and Piping Assembly
25
4.6.1
Overview of assembly
26
4.6.2
Mechanical Analysis
27
4.6.3
Fluid Flow Analysis
28
Frame Assembly
29
4.7.1
Overview of System
30
4.7.2
Mechanical Analysis
31
CHAPTER 5. MATERIAL SELECTION
5.1
32
Bill of Materials and Cost Analysis
CHAPTER 6. FABRICATION PROCESS
6.1
33
34
Overview
35
REFERENCES
36
APPENDIX
Appendix I
Project Timeline, Breakdown
40
Appendix II
Task Designation
41
Appendix III Fabrication Time
42
Appendix IV Part Suppliers
43
Appendix V
44
Schematics
Appendix VI Material Properties
45
8
LIST OF FIGURES AND TABLES
List of Figures
Figure 1.
Figure 2.
………………………………….32
……………………………………………………...32
Figure 3.
………………………………………………...34
Figure 4.
……………………………………………...34
Figure 5.
……………………………………...……………….35
Figure 6.
…………………………………………..…..35
Figure 7.
Figure 8.
………………………………………………………………..…36
...…………………………………………..69
Figure 9. ………………..………………………..….69
9
CHAPTER 1
INTRODUCTION
1.1 BACKGROUND INFORMATION
Internal Combustion Engine
The internal combustion engine has been around for A VERY LONG TIME. The
concept involves the use of a fuel and air as an oxidizer inside a combustion chamber that
through combustion, an explosion within this chamber exerts a force on a component of the
engine to provide rotational motion. The most common type of internal combustion engine is the
reciprocating piston type. This engine typically burns gasoline or diesel fuel that is mixed with
air from the atmosphere. The pressure created from the combustion process from this exothermic
reaction is what pushes down on the piston. This reciprocating motion of the piston is converted
into rotary motion through a connecting rod and crankshaft arrangement.
There are two main types of reciprocating engine. They are grouped according to the
number of strokes required for a complete power cycle of the engine. The more basic is called
the 2-stroke engine. The other type is the 4-stroke engine and will be the focus of this project.
The 4-strokes are necessary for the function of the engine. The first stroke involves the opening
of the Intake valve on the downward stroke of the piston. This causes a drop in cylinder pressure
and allows air to flow from the atmosphere into the
cylinder through a series of conduits or a “manifold”
which is also controlled by a throttle mechanism.
This mechanism could be either a throttle body such
as those used in fuel injection systems or via a
carburetor which serves as a fuel metering device.
The 2nd stroke is called the compression stroke. The
piston is now moving up with both the intake and
exhaust valves closed. The air and fuel is compressed
leaving a small area of high pressure called the
combustion chamber. The ratio between the swept
volume of the piston and the remaining volume of the
combustion chamber is called the compression ratio.
Figure 1.1 Piston-Crankshaft Assembly
This can be anywhere from 6:1 found in lawnmower type engines to as high as 13:1 in high
10
performance motorcycle engines. Typically the higher the ratio the more efficient the engine but
higher quality fuels are required. The run-of-the-mill automobile engine has a compression ratio
of 9:1. The third stroke is called the power stroke. The fuel and air mixture is ignited when the
piston is at the top of the cylinder by the sparkplug. The flame front propagates through the
cylinder quickly building extremely high pressure; meanwhile the piston is traveling down the
cylinder by the force provided. This is called the power stroke. As the piston is reaching the
bottom of the cylinder, the exhaust valve begins to open allowing the spent gasses to exit the
engine. The piston is now moving back up pushing the remainder of the gasses out, this is known
as the exhaust stroke. The 4 strokes are completed and the cycle begins again. Power is only
produced once every other revolution of the engine by each cylinder. The combination of this
power cycle and the timing at which these strokes occur, make for a continuous power band right
at the flywheel which is what transmits power to the rest of the vehicles’ drive train. The 4-stroke
engine can be modeled as a simple pump. The more air that can enter and exit the engine, the
more fuel that can be burned and thus more power can be produced. The pressure that is exerted
on the piston is
converted into rotary
motion and a torque.
Power on the other
hand is force times
velocity. Velocity is
distance over time. We
can deduct that the
power developed by the
engine depends on the
number of times this
power stroke occurs
Figure 2.3 Otto-Cycle Pressure-Volume Graph
or the magnitude of the force created.
11
Internal Combustion Engine Performance
How can these engines produce more power? Engine designers have devised many clever ways
to approach this problem. One method is to make the engine larger. Other opted to use higher
octane fuels. But due to fuel prices increasing everyday and environmental issues with
hydrocarbon-greenhouse gas contamination concerns the latter is no longer a viable solution.
The next method involves increasing the engines volumetric and thermo efficiencies. This in a
way decreases the fuel consumption as well as its carbon footprint in the environment.
Volumetric efficiency is the percentage of air that enters the cylinder as compared to the
actual swept volume of the piston. At first, it seems that this should always be close to 100%.
In fact this is far from the truth. The air has to enter the engine through an arrangement of
devices. First there is the air cleaner that provides restriction. Next we have the ducting leading
to the Mass Airflow sensor (Modern fuel injection systems use this to calculate the amount of air
entering the engine). Next we have the throttle body and intake manifold. From here we have
the intake port and the intake valve and finally the cylinder. At low rpm the restrictions are
small but one has to keep in mind that engines spin very fast (at times exceeding 7000 rpm) and
this intake stroke occurs many times per second. The amount of air entering the engine is in the
order of many cubic meters per second. It is not uncommon for engines to have volumetric
efficiencies in the 70-80%. One factor that can lower this number is heating of the air due to hot
engine components. The base value is take at standard temperature and pressure meaning that the
hotter the air the lower the volumetric efficiency.
Thermal efficiency of an engine involves the conversion of energy from the fuel to energy that
can be used at the output of the engine. Modern engines rarely see a thermal efficiency over
30%. This means that out of all the energy produced in the combustion of the fuel and air
mixture less than 30% is converted into power. The rest exits the engine as waste heat through
the cooling system and exhaust and also as noise. New materials such as ceramics are being
tested to increase this efficiency but the most cost effective method is to raise the compression
ratio. Higher compression ratios require fuels with higher octane ratings and are very expensive.
If lower quality fuel is used the engine can be damaged by detonation also know as pinging.
With the quality of fuels and detonation setting a limit on how high a compression ratio can be
used, what other alternatives does an engineer have? This leads us back to increasing volumetric
efficiency. The best method to do this is with forced induction. Forced induction, as the name
implies, is a method of increasing the pressure of the air entering the engine. This has multiple
12
benefits, as the engine no longer has to draw the air in during the intake stroke, it is now being
pumped in which allows the possibility of burning more fuel.
Supercharging has been around almost as long as the reciprocating internal combustion
engine. The technology was greatly advanced during World War II when the world’s nations
needed to achieve a level of air superiority to survive or win the war. The fighter planes of the
time used large radial piston engines. As airplanes flew faster and higher they needed a way to
combat the loss of power caused by the low air pressure and density (decreased the volumetric
efficiency) during high altitude flying. Supercharging was the perfect answer.
Superchargers can be broken down into two main groups. The first of the two is the
exhaust driven supercharger which is
more commonly called a
turbocharger. The name comes from
the fact that the engines exhaust
drives a turbine that is connect to a
centrifugal compressor feeding the
intake charge of the engine. The
second type, the group that will be
covered in this project, is the
mechanically driven supercharger.
This system is most commonly driven
from the engines crankshaft either
through gears or belts. Within the
realm of mechanically driven
superchargers there are 2 more
Figure 3.4 Roots Supercharger Efficiency Graph
common types, the centrifugal and the roots-type supercharger. The roots type supercharger is
known as a positive displacement pump. This pump, delivers a nearly fixed volume of air per
revolution at all speeds. By inspection, the efficiency of the roots type supercharger is best at low
speed. However, at higher rotational speeds, the efficiency tends to diminish to about 50%. At
this point, the air charge in the supercharger, due to compression, does heat the air charger. Due
to this increase in heat, intercoolers are used to cool the air via a water-to-air intercooler or airto-air intercooler. Centrifugal type superchargers do in fact portray this same behavior however;
they do offer a more efficient functionality.
13
Roots type superchargers are more common in
daily driven vehicles because of their ease of
maintenance and good overall efficiency. The
fact that the engine speeds for normal daily
transportation are not as high as in racing
applications, the use of a lower speed, higher
efficiency device such as a roots supercharger
is opted by automakers. These superchargers
are the ones chosen by all American,
Figure 4.1 M62 Eaton roots Supercharger Cobalt SS-GM
European and Japanese automakers. One
such company supplying a very high market
segment of the supercharger industry is Eaton Corporation, dominating with over a 60% of the
market segment for supercharger applications for domestic and import vehicles. Their new
technology involves a patented abradable powder coating which increases volumetric efficiency
by closing up the gap between the twin screw blades and the casing of the supercharger
assembly.
As for the drive system for
supercharged engines, they are usually
engaged using a belt drive system. At
this time, there are only a few
manufacturers who have attempted to
install a clutch within the supercharger
assembly thus controlling the actual
operation and boost. In the past, Toyota
had this system in the MR2 and
Figure 6.1 Eaton Roots Supercharger
consequently was used in Mercedes Kompressor line models as well as the renowned
Volkswagen Golf which uses both a supercharger and a turbocharger in their 1.4L TSI inline 4
engine.
14
Figure 5 VW 1.4L TSI Twin Charged Engine
1.2 CURRENT TECHNOLOGY
There is a great deal to explore a way to control the actual boost and performance of an engine
using a supercharger. As of today with a few exceptions to some manufacturers, the most
economical way to control boost in a supercharger is by way of changing its pulley at the nose of
the device. By changing this pulley, the rotational speed is changed thus increasing/decreasing its
boosting capacity hence changing the superchargers operating efficiency. In order to control the
superchargers’ operation, VW as well as Mercedes Benz have used magnetic coupling engaged
superchargers. These systems were more cumbersome than what they actually were designed for.
The clutch system was based on the normal air conditioning compressor clutch system often used
in the automotive industry. This clutch, is based on a
magnetic, friction drive coupling mechanism of which
was activated at the moment the driver wanted to
activate the A/C on the vehicle, a current was sent to
the clutch, magnetizing the components and through
the friction provided by the engagement of such plate
against the pulley assembly, the compressor engaged
and provided the necessary power for the air
Figure 8 A/C Clutch system for automobiles
conditioning system to work. With this idea, the auto
manufacturers were able to have some sort of control of the supercharger. However, the
functionality of this system is constrained by an “ON” or “OFF” operation. There is no variable
control on the supercharger and for this matter, the
supercharger operation was compromised. This
cycling operation of the supercharger does not in
itself provide the “ultimate” performance and
efficiency numbers it once was designed for. This
cyclical operation also proved to be damaging for
the superchargers. The nose or front end of the
supercharger, where the pulley is connected to, has
a bearing/coupling which was designed to dampen
the rotational shock it would receive when the
engine encountered shifting of gears, over revving Figure 7.1 Mercedes Benz Supercharger with
Electromagnetic Clutch
and the actual turning on of the engine.
15
As to controlling boost on the engine, the most typical and cost effective way is by changing
pulleys. By changing the diameter of the pulley, the rotational speed of the supercharger is
increased or decreased. Such an increase or decrease of this rotational speed, will impact the air
flow going through the supercharger to the engine. At this point, the smaller pulley will allow
more air flowing through the supercharger and
at the same time “flood” the engine with more
air than that of what it needs. This overflow of
air in the system is called “boost” or pressure.
As it has been discussed, the actual boost
control in a supercharger is limited to a
physical modification of the supercharger
pulley assembly or limited by an “on” or
“off”operation which it does not provide an
Figure 9.1 Different Supercharger Pulley Sizes
useful means of properly controlling the boost and efficiency of the supercharger and the engine
in the automobile. Our proposed system will attempt to have full control of the engagement of
the supercharger by means of using a frictionless, magnetic drive coupling which will be
controlled by the engines’ electronic control module.
16
1.3 RELATED ENGINEERING TOPICS
Magnetism
In the world of physics, we have what is called Faraday’s Law of Induction. This law states that
the induced or electromotive force in a closed loop is directly proportional to the time rate
change rate of magnetic flux through the loop. In layman’s terms, if a conductor is moved
through a magnetic field, it will produce a voltage in the conductor itself. The resulting voltage is
proportional to the speed this conductor is moving, hence if we move the field, constantly, and
then there will be a flow of current (voltage) throughout the conductor, making it move at the
same rate.
Faradays’ Law is as follows:
ε = −N
Where
ε
dΦ B
dt
is the electromotive force (EMF) in volts
N is the number of turns in a wire
ΦB is the magnetic flux in Weber’s through a single. The minus or negative sign is the
actual direction of the electromotive force (Lenz’s law)
Mechanics
Pending
17
CHAPTER 2
DESIGN CONCEPT
2.1 GOAL STATEMENT
The goal of this project is to develop a variable, magnetically induced, frictionlessengagement supercharger clutch system with an electronic control unit to be used in automotive
internal combustion engines.
2.2 OBJECTIVES
There are many objectives to this particular project. First, the designed system will
eliminate a direct mechanical connection (contact area) between the drive system and the
supercharger. This system will have the capability of fine tuning the boost provided by the
supercharger at a more direct level depending on the different driving conditions. Within the
many functions of this entire system, a method of disengagement of the supercharger is to be
implemented in the operation of such engagement system. This particular clutch/engagement
system must have the flexibility and capability to be adaptive for daily driven vehicles as well as
Heavy Duty commercial vehicles and also for high performance, racing class vehicles. Finally, a
main objective of this project is to reduce the wear and tear components normally linked to
clutch engagement systems.
2.3 FORM AND FUNCTIONALITY
The prototype being built in this project will be mounted on a simulated engine test bench. This
bench will house an electrical motor that has enough torque and horsepower to move an M24
EATON roots type supercharger. This supercharger will provide a specified boost by controlling
the output of it through a manual valve; also the change in pressure will be monitored and
controlled by an electronic module, the Supercharger Control Unit or SCU. This electronic unit
will house all necessary circuitry and programming which will enable it to control the linear
actuators, motor, linear actuator and throttle to operate at designated points automatically. Once
the input is given to the system (i.e. supercharger load-downstream valve position and throttle),
the electronics will adjust the amount of engagement of the magnetic clutch/coupling mechanism
in order to reach a specified set point of conditions (i.e. pressure, speed etc…)
18
2.4 CONSTRAINTS AND CHALLENGES
This project presents many challenges that we will have to be prepared and in some
instances over engineer the design for our own safety. This clutch system must engage properly
when the appropriate torque is set as well as the distance between magnetic plate and conductor
plate. One challenge is to measure the actual speed of both the motor and the actual supercharger
by using magnetic pickup devices. These devices are susceptible to interference and given that
the NIB-magnets used in this project are very powerful, the measurements might be somewhat
off, so this in itself will pose a challenge into the positioning of these sensors. As to the test
bench, we have acquired a high density particle board test bench which is mounted on a steel
cart. The cart is able enough to handle the weight and structure itself, but the actual particle
board could provide unnecessary deflections when the clutch is engaging completely. This will
have to be tested and dealt with at the appropriate time. Another challenge is that we are working
with an electrical motor of which we know only a little and not to mention we acquired it as
refuse, not knowing the condition; it was nominally rebuilt it to its original condition. This motor
was part of a commercially available go-kart thus it was thoroughly examined, cleaned and
partially matched to a 3-4 hp, electric DC motor capable of spinning around 3600 rpm. This
supercharger, though small in size, it will require a horsepower rating of between 5-10 hp in
order to peak its maximum operating conditions. However, we will need to limit our testing to
what the motor is available and through the use of different size pulleys. Given that the motor is
DC, we have opted to have a bank of batteries to totaling the 36 volts needed to power it. This in
itself will prove itself challenging given the fact that the batteries will have a specified running
time and we are hoping the power will be enough to power the supercharger, under full load
conditions and full engagement. Finally, it is our first time handling very powerful neodymiumiron-boron magnets and though they are small in size, they do have a lot of pulling force. If for
some reason we loose grip of these magnets during fabrication or testing, someone can get hurt.
A challenge for this is to build a safety cage or cabinet that could be installed without blocking
the view of the system. This cage or cabinet will have to be built out of a clear, transparent
material (i.e. LEXAN) and should be molded and conformed in such a way it doesn’t become a
hindrance while operating the test bench. As for costs, we are not in the process of economizing
at this stage since most of the components must and will be custom made.
19
2.5 TARGET CLIENT/INDUSTRY
The target clientele for this device would ultimately be the automotive industry. Given that some
companies have attempted a similar technique of controlling the engagement of the supercharger
for high output engines, it seems reasonable that they would be interested in at least gathering
this product or a prototype of such to test in one of their vehicles. In addition to this, we have
confidence that this system will be very attractive to the racing industry. Supercharger systems
are commonly used in truck and tractor pull competitions as well as in drag racing. It is in these
areas where supercharging is widely used and controlling such would offer advantages in engine
operation and performance. Most importantly, I would not be surprised if any aftermarket
supercharger manufacturing company would approach us interested in this clutch mechanism.
Companies such as Eaton Corporation, Paxton Superchargers, VF Engineering and many more
are some of the aftermarket companies which could target this system for their implementation in
their own applications.
20
2.6 DESIGN SPECIFICATIONS
Function
•
Motor speed of ~3600 to 4000 rpm
•
Boost, air pressure from 1-10 psi
•
Variable, linear engagement of magnet assembly, 1.5” to 0”
•
Immediate response of linear actuator moving the magnet assembly
•
Ability to acquire data from system using pressure sensors, tachometers and other
metering devices to monitor and extrapolate systems operation.
Form
•
6 ft long high density particle board mounted on 36” high cart with rolling casters
•
System must be mobile and ready to test any supercharger assembly.
•
Test apparatus will have a mobile computer station with all necessary software packages
for DAQ and analysis suites.
Interface/Operation
•
System will be operated via manual switch to turn on electronics on board test bench,
including a pedal/throttle control similar to that found in a regular automobile
•
Manual control of load application to the supercharger via adjustable ball valve (air flow
control)
21
2.7 BILL OF MATERIALS
Bill of Materials
Item name
Used in
Make
Purchase
Material
Quantity
Vendor(s)
Part
Number
Motor
Power Input
Donated
N/A
1
FIU Surplus
N/A
Supercharger
Forced
Induction
Donated
N/A
1
Eaton
N/A
AC motor
speed
control
Purchase
Test bed
Donated
Inverter
Test bench/Frame
Linkage
N/A
1
Steel
1
Clutch
make
Rubber
4ft
Magnetic drive
Clutch
Make
Purchase
N/A
1
Throw out
bearing
Clutch
Purchase
Steel
1
Wiring
Batteries
Computer
Software Package
Video Capturing
System
Lights
Toolbox
motor/linka
ge
Purchase
Motor
Purchase/
Donation
N/A
Personal
N/A
speed/torque
monitor and
control
DAQLabView
and Design
Software
Package
Real time
visual of
working
mechanism
illuminate
key parts to
be
monitored
storage
N/A
N/A
3
N/A
N/A
FIU Surplus
Aeroquip,
Miami
Magnet Sales
Manufacturing
Summit
Racing/EBAY
$500.00
$1200.00
$1200.00
$400.00
$400.00
$100.00
$100.00
$200.00
$200.00
$1,000.00
$1,000.00
$100.00
$100.00
$1,000.00
$100.00
$200.00
$200.00
$500.00
$500.00
N/A
N/A
$100.00
$100.00
$20.00
$200.00
$300.00
Total Amount:
$300.00
$4900.00
N/A
N/A
N/A
N/A
8828
Radio Shack
Digikey
Jameco
N/A
Advance Auto
Parts
N/A
HP
N/A
N/A
N/A
N/A
N/A
Personal
N/A
N/A
Brandsmart ,
Ebay
N/A
buy/donate
N/A
5 to 10
steel
1
22
Radio Shack
N/A
Total Cost
$500.00
LabView,
Microsoft
Office
buy/donate
Unit cost
N/A
N/A
2.7 FUNCTIONAL ANALYSIS
FUNCTION MEANS TABLE
Function
Magnetically
Coupled
Supercharger
system
Sub-Function
Means
Ability to control the
smooth engagement
and disengagement of
clutch
Common clutch
slave/master
hydraulic setup
Servo Motors/ linear
actuators
Drive by
wire/actuators
Manual
engagement
Ability to control boost
Pedal/shifter setup
Steering wheel Push
buttons
Paddle shifters
behind steering
wheel
VSS/ECM
automatic boost
control
System can switch from
economy mode to
performance mode
upon user preference
ECM can select
according to driving
condition
Operator can
arbitrarily choose
what mode through
switch/lever
mechanism
System design for
specific
application (HD,
Racing etc…)
Reduce noise and
vibrations
Rubber/Polyurethane
system mounts
Fluid filled Dampers
No solid link
between
crankshaft to belt
drive system
23
CHAPTER 3
SOLID MODELING/IMAGERY
3.1 PRELIMINARY IDEA
First Generation of the clutch system
24
3.2 REALIZED IDEA
2nd Generation clutch design
Solidworks rendering
of the magnet
assembly. The extra
material cut off from
the edges of the
pockets account for
the actual glue or
adhesive used for the
attachment of the
magnets. This also
provides ease of
access if magnets
need to be removed
and or refitted.
CNC Machined 8”
diameter round stock
6160 Aluminum. The
pockets will hold the
NeFeB magnets, 16 in
total.
25
26
3-D rendering of the clutch
assembly mounted on the
surface of the test bench.
The rendering shows the
self aligning pillow blocks,
v-type and serpentine
pulleys, splined shaft with
both the magnet holder and
the conductor plate
(bronze).
This is an actual picture of the system
already in place. The engaging system is
being finalized at this moment and final
testing and DAQ of parameters will be
finalized. Equipment has been preliminary
tested
27
3.3 DRAWING LIST
All drawings will be referenced in a list. These are the 2-D renderings. Still pending complete set.
28
29
30
31
32
33
34
35
CHAPTER 4
ENGINEERING ANALYSIS
4.1 ENGINEERING ANALYSIS
Here a brief explanation of the different areas of analysis
Magnetic simulation…still pending
36
4.2 Magnet Assembly
2nd Generation Magnet assembly with stress and displacement analysis done in Solidworks
37
38
4.3 shaft and block assembly
Input shaft from motor to
housing. This is a rendering
of the 19 teeth splined shaft
used to transmit power from
the motor to our
supercharger. Below a static
displacement and stress
deformation analyses
performed using
Cosmoworks
39
40
4.4 Fluid analysis
Still pending
41
CHAPTER 5
MATERIAL SELECTION
Still pending
42
CHAPTER 6
FABRICATION PROCESS
6.1 STAGE 1-GATHERING MATERIALS AND EQUIPMENT
For our first stage in our fabrication process, we had to gather all possible components
that we have specified for our build. The following alludes to all the situations we had
encountered so far to make this project come alive:
Supercharger Assembly
We went through great lengths in finding a sponsor for this project. Our group finally got
sponsorship from EATON Corp. with their contribution of a brand new M24 supercharger:
Brand new, M24 supercharger, suggested
retail price, $2750. Free!!
This picture shows our planned location
for the clutch system. Eventually we decided
that this was not the best place to install our
prototype.
43
The following show the actual vanes of the supercharger. We can see they have a “graphite
looking” coating on them. This is the TVS specialty coating EATON has specially designed to
increase the efficiency on its 5th
generation superchargers. This particular
picture shows the inlet plenum of the
supercharger where a throttle body will
be installed.
This is the lower plenum or the output of
the supercharger. Notice the vanes are
dark and a somewhat porous finish to it.
This plenum will be the mounting
surface of the supercharger to our test
bench. Appropriate gasket material will
be used to create a perfect seal between
the mating surfaces.
44
Test Bench
The fact that we did not have a vey sturdy platform onto which we would build our test bench,
we needed to either fabricate or purchase a sturdy frame. After extensive searching, we gathered
some things from surplus and our near by trash collection bins, of which saved us a lot of money.
Frame
This frame is a steel frame
complete with casters. This will be
the support structure for the entire
test bench. It is made out of sturdy
steel material; it is nicely finished,
though it will need some additional
framing and some painting.
Motor/Housing
Our group was exhausting every possible vendor who had
AC and DC type motors. Unfortunately nobody seemed
interested in donating a motor that sufficed our
specifications. Being in the difficult position of hunting a
very expensive component, we opted to search online
through auction websites to order a cheap motor, risking
that it would not hold to our specifications. Throughout our
search, and through local shops in Miami, our group paid a
2nd visit to FIU surplus and to our luck, surplus had disposed
of a complete golf cart used by facilities. The cart was in
bad condition but, in fact this one was fitted with an electric
motor, a DC motor in fact. We proceeded to acquire the motor and we gutted the entire rear end
of the cart which holds the differential and motor housing and the motor. After disassembling the
45
rear end, we proceeded to check the integrity of the motor and machine/prepare the
motor/differential housing for the installation.
In these pictures, Richard A. Castillo is removing the axles and differential components of the
housing for the installation.
46
These are the remaining parts from the
differential. There are stored until the build
is completed. There might be some useful
parts here.
If we were to purchase a new motor, it would’ve looked like this
The motor itself was somewhat dirty but we managed to clean it and test it. At first it wasn’t
working properly, so we proceeded to open the actual motor case and inspect it. You can better
grasp the size of the motor, note the wd-40 11oz. can next to the stator and hub assembly.
47
Through inspection, we saw some of the electromagnets within the motor stator assembly a bit
discolored and the polymer coating a bit melted through. Even though these were signs of wear
and possible damage, we did not see any burnt or destroyed elements within the magnet
assembly.
48
Motor/Battery Mounting
AC to DC converters where
priced too high for our budget, so
we decided to opt for a more
conventional power supply,
batteries. We needed a battery
setup that had a 36 volt capacity
for this motor. Since the motor
seems to have a good amount of
power or current draw, we opted
for a series of automotive/farm
equipment batteries, readily
available at a local auto parts store.
This is the bench with a
high density particle
board attached to the
bottom rail. Onto this
board, we have fixed
the bank of batteries as
well as the motor
housing.
49
Belt Drive
The following pictures are of the actual motor mount. This motor mount not only holds the
motor in place, it acts as the main front mount bearing to the motor assembly. In addition, the
input shaft is built into the motor mount or differential. Once we saw this setup, we took
advantage of the actual engineering of such components and decided to customize the
differential/motor mount to accommodate the project.
The area marked in red is the area where the internal shaft of the motor is located. This shaft is
the intermediate gear shaft that propels the differential ring gear to provide traction to the real
propulsion wheels on the go cart. The following is the main input shaft from the motor to the
differential housing
50
Area in red indicating cut out section to expose the shaft assembly that will provide rotational
speed and torque to the supercharger assembly. The following is the actual pulley fitted within
the housing into the input shaft along with a V-belt:
51
Final Building Stage
The electrical team is in the process of detailing all electrical connections and making sure all
controls are working properly. Data is still to be gathered. Once system is in full operation, data
will be acquired and analyzed. The build is shown below:
52
This picture entails the actual supercharger outlet. The control volume is approximately
1300 cc, the maximum capacity of flow this supercharger is capable of.
53
References:
Course Related Books:
•
Book used to identify and analyze electromagnetic and electrical components
involved in magnetic systems and its theoretical calculations.
Griffiths, David J. (1998). Introduction to Electrodynamics (3rd Ed.) Prentice Hall.
ISBN 0-13-805326-X.
•
Hambley, Allan (2007) Electrical Engineering Principles and Applications (4th
Ed.) Prentice Hall. ISBN-10: 0131989227
•
Tipler, Paul (2004). Physics for Scientists and Engineers: Electricity, Magnetism,
Light, and Elementary Modern Physics (5th Ed.). W. H. Freeman. ISBN 0-71670810-8.
Journal Related References:
•
Maekawa, H. and K. Komoriya, Development and Eval. of a Passively Operating
Load-responsive Transmission, Proc. of IEEE Technical Exhibition Based Conf.
on Robotics and Automation, pp. 31-32, 2004.
•
Maekawa, H., Y. Gotoh, K. Sato, M. Enokizono, and K. Komoriya, Development
and Evaluation of a Passively Operating Non-Contact, Load-Responsive
Transmission, Proc. of IEEE Int. Conf. on Robotics and Automation, pp. 40714078, 2004
•
Maekawa, H. and K. Komoriya, Development of a Passively Operating LoadResponsive Transmission, Proc. of IEEE Int. Conf. on Robotics and Automation,
pp. 194-201, 2003
•
http://meweb.ecn.purdue.edu/~metrib/Fac/clutch.whtml
•
Cater M., Bolander N.W.,Sadeghi F., "A Novel Suspended Liner Test Apparatus
for Friction and Side Force Measurement with Corresponding Modeling,"2006
SAE Small Engine Technology Conference in San Antonio, Texas
Vendor Related References:
54
•
Magnet Sales and Manufacturing Inc. They are manufacturers of custom magnet
assemblies and magnets for various applications. www.magnetsales.com
•
Magna Drive Corporation. Designs and builds magnetic coupling devices
commonly used in industrial applications such as pumps, generators etc…
www.magnadrive.com
•
www.levx.com, www.magna-force.com
55
Appendix A
The following is a picture of the test vehicle used for the data logging of parameters to be used for the development of the SCU control unit:
56
Appendix B
The following are data points that were collected through many runs on the test vehicle. These will be used for the system control design:
57