Vehicle Mounted Pneumatic Car Jack
by
FAIZAN NASIR
Submitted to the
MECHANICAL ENGINEERING TECHNOLOGY DEPARTMENT
In Partial Fulfillment of the
Requirements for the
Degree of
Bachelor of Science
Ill
MECHANICAL ENGINEERING TECHNOLOGY
at the
OMI College of Applied Science
University of Cincinnati
May 2009
© ...... Faizan Nasir
The author hereby grants to the Mechanical Engineering Technology Department
permission to reproduce and distribute copies of this thesis document in whole or in part .
..--- .
AI
Signature of Author ----------~·1-r--=·f:::::.&:.::"'.:.:,'--"t...:..:c:vt~=-~..£_---Mechanical Engineering Technology
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Certified by _ _ _ _ _ _ _ _
Ahmed Elgafy, pJU:f,
U
Accepted by
utnar Al-Ubaidi, P , Department Head
Mechanical Engin~ing Technology
Vehicle Mounted Pneumatic Jack
By: Faizan Nasir
June 5, 2009
Advisor: Prof. Ahmad Elgafy
TABLE OF CONTENTS
TABLE OF CONTENTS .......................................................................................................... II
LIST OF FIGURES ................................................................................................................ III
LIST OF TABLES .................................................................................................................. IV
ABSTRACT............................................................................................................................. V
INTRODUCTION .................................................................................................................... 1
BACKGROUND ................................................................................................................................................... 1
MANUAL JACK SYSTEMS .................................................................................................................................... 1
STANDARD MANUAL CAR JACK .................................................................................................................. 1
MANUAL HYDRAULIC JACK ....................................................................................................................... 1
AUTOMATIC JACK SYSTEMS ............................................................................................................................... 2
STANDARD DESIGN AUTOMATIC HYDRAULIC JACK ................................................................................... 2
HYDRAULIC PUMP - PISTON DESIGN CAR JACK .......................................................................................... 3
EASY LIFT HYDRAULIC CONVERSION JACK KIT.......................................................................................... 3
EXHAUST POWERED AIRBAG………………………………….……………………………………….………………………4
CUSTOMER FEEDBACK, FEATURES, AND OBJECTIVES ............................................. 5
SURVEY ANALYSIS ............................................................................................................................................ 5
QFD RESULTS ................................................................................................................................................... 6
PRODUCT FEATURES AND OBJECTIVES .............................................................................................................. 8
CONCEPT GENERATION AND SELECTION……………………………………………………………….….10
HYDRAULIC CAR JACK DESIGN……………………………………………………………………………………………………. 10
PNEUMATIC CAR JACK DESIGN……………………………………………………………………………………………..……....10
EXHAUST POWERED JACK DESIGN…………………………………………………………………………………………..….….11
CONCEPT SELECTION…………………………………………….…………………………………………………………..…….… 12
FINAL DESIGN…………………………………………….…………………………………………………………..…….…………..13
DESIGN CALCULATIONS……………………………………………………………………………………………….…14
CENTER OF GRAVITY/JACK LOCATION…...…………………………………………………………………………………………14
DESIGN LOAD CALCULATIONS……………..…………………………………………………………………………………………15
SHIELD STRESS ANALYSIS …………………………………………………………………………………………………………….16
LOWER PLATE STRESS ANALYSIS ……………………………………………………………………………………………………18
AIRBAG ANGLE……………………. …………………………………………………………………………………………………….18
MOUNTING STRESS ANALYSIS………………………………………………………………………………………………………...18
COMPONENT SELECTION /DESIGN………………………………………………………………………………..19
AIRBAG SELECTION………………………………………………………………………………………………………………...…….19
AIR COMPRESSOR SELECTION………………………………………………………………………………………………………….21
AIR HOSE……………………………………………………………………………………………………………………………………22
PROTECTIVE SHIELD / MOUNTING……………………………………………………………………………………………………..23
FABRICATION…………………………………………………………………………………………….………………………...23
SHIELD/MOUNTING ASSEMBLY…...……………………………………………………………………………………….…………..23
SHIELD CASE……………..…………………………………………………………………………………………………….……...…..24
REAR MOUNTING BRACKET ……………………………………………………………………………………………………...……25
FRONT MOUNTING BRACKET ……………………………………………………………………………………………….…………26
SHIELD CASE UPPER BRACKET …………………………………………………………………………………………….………….27
SHIELD COVER ………………………………………………………………………………………………………………….………...28
LOWER PLATE …………………………………………………………………………………………………………………………….28
SYSTEM ASSEMBLY……………………………………………………………………………………………….…………...29
SHIELD-AIRBAG JOINING…...…………………………………………………………………………………….……………………..29
ii
SHIELD MOUNTING……………..………………………………………………………………………….…………..……………...30
LOWER PLATE JOINING ………………………………………………………………………………….…..……………………….32
AIR HOSE/FITTINGS …………………………………………………………………………………………………………………...32
AIR COMPRESSOR MOUNTING …………………………………………………………………………………………….………..33
AIR HOSE ROUTING ………………………………………………………………………………………………………….………..34
TESTING…………………………………………………………………………………………….………………………………..34
AIR-LEAK TEST………………………………………………………………………………………………………………...………...34
LOAD TEST……………………………………………………………………………………………………………..............................34
OPERATION PROCESS…………………………………………………………………………………………….………..35
PROJECT MANAGEMENT……………………………………………………………………………………….………..36
SCHEDULE ……………………………………………………………………………………………………………………………….36
BUDGET …………………………………………………………………………………………………………………………………..37
RECOMMENDATIONS AND CONCLUSION ................................................................... 38
REFERENCES ....................................................................................................................... 39
APPENDIX A: RESEARCH ................................................................................................ A-1
APPENDIX B: CUSTOMER SURVEY AND RESULTS .................................................. B-1
APPENDIX C: QUALITY FUNCTION DEPLOYMENT ANALYSIS ............................. C-1
APPENDIX D: SCHEDULE……………………………………………………………….D-1
APPENDIX E: PRODUCT OBJECTIVE MEASUREMENTS AND RESULTS …….......E-1
APPENDIX F: BUDGET…………………..……………………………………………………………….………F-1
APPENDIX G: DESIGN CALCULATIONS ……………..……………………………………………….G-1
APPENDIX H: ASSEMBLY AND DETAIL DRAWINGS …………..……………………… ……H-1
APPENDIX I: PURCHASED COMPONENTS.....…..……..………………………………………………I-1
APPENDIX J: AIRBAG SELECTION GUIDES …………....………..……………………………....J-1
APPENDIX K: BILL OF MATERIALS…………....………..……………………………………………....J-1
LIST OF FIGURES
Figure 1- Standard Manual Jack
Figure 2- Manual Hydraulic Jack
Figure 3- Standard Design Automatic Hydraulic Jack
Figure 4- Single Unit Hydraulic Pump-Piston Automatic Jack
Figure 5- Separate Fluid Reservoir Hydraulic Pump-Piston Automatic Jack
Figure 6- Easy Lift Hydraulic Jack Conversion Kit
Figure 7- Exhaust Powered Airbag
Figure 8- Hydraulic Car Jack Design
Figure 9- Pneumatic Car Jack Design
Figure 10- Exhaust Powered Car jack Design
Figure 11- Final Design
Figure 12- Test Vehicle
Figure 13- Center of Gravity Location
Figure 14- Wheel-Vehicle-Jack Lever System
1
2
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3
3
4
4
10
11
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iii
Figure 15- Projected Bearing Contact Area
Figure 16- Shield Stress FBD
Figure 17- Lower Plate Stress FBD
Figure 18- Convoluted Air Spring
Figure 19- Type 1 Bead Design
Figure 20- Airbag Material Selection
Figure 21- Airbag Selection Chart
Figure 22- Airbag Force Table
Figure 23- Firestone Airbag
Figure 24- Campbell Hausfeld Air Compressor
Figure 25- EPDM Air Hose
Figure 26- Shield/Mounting Assembly
Figure 27- Shield/Mounting Assembly Side View
Figure 28- Shield Case Bottom
Figure 29- Shield Case Top
Figure 30- Corner Brackets
Figure 31- Corner Brackets Weld
Figure 32- Rear Mounting Bracket
Figure 33- Rear Mounting Bracket Weld
Figure 34- Front Mounting Bracket
Figure 35- Front Mounting Bracket Welded
Figure 36- Shield Case Upper Bracket
Figure 37- Shield Case Upper Bracket Welded
Figure 38- Shield Cover
Figure 39- Inserted Shield Cover
Figure 40- Lower Plate
Figure 41- Airbag Shield Joining
Figure 42- Airbag Shield Bolts
Figure 43- Shield Mounting Locations
Figure 44- Shield Mounting Rear View
Figure 45- Shield Mounting Front View
Figure 46- Front Mounting Bracket Bolt Location
Figure 47- Lower Plate Mounting
Figure 48- Air Hose Fittings
Figure 49- Elbow Fittings
Figure 50- Air Hose – Airbag Fitting
Figure 51- Air Compressor Mounting
Figure 52- Air Hose Routing
Figure 53- Airbag Deflated Position
Figure 54- Airbag Inflated Position
17
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20
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21
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22
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23
24
24
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36
36
LIST OF TABLES
Table 1- Survey Results of Customer Importance
Table 2- Survey Results of Customer Satisfaction
Table 3- Relative Importance %
Table 4- Relative Weight %
5
6
6
7
iv
Table 5- Weighted Decision Matrix
Table 6- Schedule
12
37
ABSTRACT
There are many safety hazards posed with manually raising a vehicle to change a tire.
Standard car jacks pose a great safety hazard due to the physical and time consuming
involvement of the operator. Aftermarket automatic hydraulic jacks though safer still are
hazardous as they have to be manually placed under the vehicle and have limited use. A
pneumatic car jack that is permanently attached to the underbody of a vehicle will reduce and
eliminate many of these safety issues. A customer survey of approximately equal number of
male and female drivers was conducted. According to the customer survey, safety, reliability
and durability are the most important factors for customers when considering a vehicle jack
product. The same customers are least satisfied with accessibility of controls, speed of operation
and ease of operation of their current vehicle jack system. The results of the QFD matrix show
that ease of operation, accessibility of controls and energy efficiency have the highest relative
weights. The QFD also shows that power, material and safety have the highest relative
importance. Measurable engineering features were derived from the customer requirements to
ensure that customer requirements can be applied in the design process. These engineering
features in order of relative importance are power, material, safety, maintenance, number of
components, weight, size, guarding, manufacturability, actuation method and installation setup.
The pneumatic jack was designed based on the relative weights of the customer requirements
that are given the most importance and the engineering features with the highest relative
importance in order to ensure that customer needs are met. This approach ensured that the car
jack was designed with the customer’s needs in sight and thus proved to be a successful product.
The schedule for the design process was approved by the advisor and the Final Report due date is
June 5th. The budget for the design and manufacturing of the product includes all major
components such as airbag, air compressor, protective shield, air hose and mounting hardware.
The expenses shown in the budget were covered by the designer of the product.
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INTRODUCTION
BACKGROUND
The standard vehicle jacks require the operator to retrieve the jack from the trunk, place it
under the vehicle in the proper location, and then manually rotate the screw thread in order to lift
the vehicle. This process is time consuming, physically demanding and poses several safety
hazards. Adverse weather conditions can exacerbate the process and make it a greater safety
hazard. Those who are physically weaker (women, senior citizens, young drivers) may face
great difficulties in jacking a vehicle in case of an emergency repair.
The purpose of this senior design project is to counter the safety hazards and physical
demands related to using manual jacks or aftermarket hydraulic jacks by designing a jack system
that is permanently attached to the vehicle. This vehicle mounted jack system will be automated
so that operator input is kept to a minimum and thus safety hazards can be avoided.
MANUAL JACK SYSTEMS
STANDARD MANUAL CAR JACK:
Most passenger vehicles come equipped with the standard manual car jack. This jack uses a
screw thread, which when turned raises or lowers the jack. Using the standard jack can be very
time consuming, physically tiring and pose safety factors. A standard manual jack is shown in
Figure 1. The horizontal screw thread in the middle, when rotated, raises or lowers depending on
the direction of rotation.
Figure 1- Standard Manual Jack (1)
MANUAL HYDRAULIC JACK:
Manual hydraulic jacks are common in most automotive workshops. They use a hydraulic
cylinder, which when pumped manually, raises the jack in the vertical direction. This type of
jack has to be manually placed under the vehicle and manually pumped. Manual hydraulic jacks
are stronger than standard manual car jacks and also require less energy to operate. Manual
hydraulic jacks tend be large in size and heavy, which makes them inconvenient to store in most
vehicles. Handling of the jack can also be an inconvenience for many operators due to their
large size and weight. A manual hydraulic jack is shown in Figure 2.
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Vehicle Mounted Pneumatic Jack
FAIZAN NASIR
Figure 2 – Manual Hydraulic Jack (2)
AUTOMATIC JACK SYSTEMS
STANDARD DESIGN AUTOMATIC HYDRAULIC JACK:
Standard automatic hydraulic jacks use the same basic lifting principle as standard manual
jacks, with the main difference being that an electric-powered hydraulic motor is used to turn the
screw thread. The power source for the hydraulic motor is the vehicles battery, and this source is
used through the cigarette lighter. Even though the process of raising and lowering the jack is
automated, the jack still must be placed under the vehicle manually. In order to operate properly,
the jack must be placed on a flat surface. This is not always an option, thus limiting the use of
the jack. The particular standard design hydraulic jack shown in Figure 3 has a short cord for the
controls. This poses a safety hazard as the operator must be present outside next to the jack
during the time of operation. In comparison to the previous two jacks described, the lifting of
the vehicle is an automatic process not requiring physical labor. However, the jack still poses
safety hazards as the operator must manually place the jack and be present in close proximity
during the operation time.
Figure 3 – Standard Design Automatic Hydraulic Jack (3)
HYDRAULIC PUMP - PISTON DESIGN AUTOMATIC JACK:
Hydraulic piston automatic jacks do not use the standard screw thread design to raise the
vehicle. A hydraulic pump is used to raise a piston, which in turn raises the car. Similar to
hydraulic automatic jack, the lifting process is automated, but the jack still requires manual
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FAIZAN NASIR
placement. This jack design is more compact compared to the standard design hydraulic
automatic jack, which makes it more convenient for storage and handling. The hydraulic pumppiston jack uses the vehicles batter as the power source, accessed through the cigarette lighter.
This jack is similar to the standard automatic hydraulic jack in that it requires the same amount
of work from the user to operate. Similarly it poses the same safety hazards due to manual
placement and alignment of the jack. Figure 4 shows a compact design in which the pump and
reservoir is in one unit. Figure 5 shows a two unit design in which the hydraulic pump and the
reservoir are in separate compartments.
Figure 4 – Single Unit Hydraulic Pump-Piston Automatic Jack (4)
Figure 5 – Separate Fluid Reservoir Hydraulic Pump-Piston Automatic Jack (5)
EASY LIFT HYDRAULIC CONVERSION JACK KIT:
The easy lift hydraulic conversion jack kit allows for the conversion of a manual jack into an
automatic hydraulic jack. Currently there is only a patent available on this procedure but no
commercial products. A manual jack is disassembled and attached to a hydraulic motor and
hydraulic pump. The motor drives a screw thread which in turn raises or lowers the jack. The
conversion requires many technical operations which the average person does not have the
resources and expertise to accomplish. Figure 6 below shows a diagram of the jack after it has
been converted.
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FAIZAN NASIR
Hydraulic Pump
Wiring
Controls
Hydraulic Motor
Jack Piston
Figure 6 – Easy Lift Hydraulic Jack Conversion Kit (6)
EXHAUST POWERED AIRBAG
The exhaust powered airbag uses exhaust gasses from the vehicles to inflate and airbag
which is used to raise the vehicle. The airbag is manually placed under the vehicle and a hose is
inserted into the exhaust pipe of the vehicle. The drawback to this design is that the airbag is
very large in size and has to be manually placed under the vehicle. Thus the operator is still in
harm’s way as the airbag is being placed. Figure 7 below shows such an exhaust-driven car jack
that is available on the market.
Figure 7 – Exhaust Powered Airbag (7)
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CUSTOMER FEEDBACK, FEATURES, AND OBJECTIVES
SURVEY ANALYSIS
A customer survey was made available to 36 people, of which 25 people returned the survey
completed. Out of the 25 surveys returned, 9 were females and 16 were male. All survey takers
are vehicle drivers who have experienced vehicle problems requiring the lifting of their vehicle
using a jack. The complete survey and results are present in Appendix B. The survey was based
on 10 customer requirements that affect the design of the product.
The first part of the survey asked the customers how important they felt each factor is in a
vehicle jack product. The survey taker was asked to rank each factor from 1-5, with 1 being low
importance and 5 being high importance. Table 1 shows the results of the customer importance
section of the survey.
Customer Importance
Rank Question Surveyed
Avg Result
1
Safety
4.92
2
Reliability
4.92
3
Durability
4.92
4
Low Cost
4.88
5
Speed of Operation
4.84
6
Ease of Operation
4.8
7
Resistance to Extreme Weather
4.8
8
Accessibilty of Controls
4.64
9
Ease of Maintenance
4.52
10
Energy Efficient
4.08
Rank 1 to 10 is Most Important to Least Important
Table 1 – Survey Results of Customer Importance
In the second part of the survey, the survey takers were asked how satisfied they are with their
current car jack product. Again the survey results were compiled and the customer requirements
are ranked from least satisfied to most satisfied. Table 2 below shows the results of the customer
satisfaction section of the survey.
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Customer Satsifaction
Rank Question Surveyed
Avg Result
1
Accessibilty of Controls
1.4
2
Speed of Operation
2.2
3
Ease of Operation
2.8
4
Safety
3
5
Energy Efficient
3
6
Reliability
3.6
7
Durability
3.9
8
Resistance to Extreme Weather
4
9
Ease of Maintenance
4.3
10
Low Cost
4.6
Rank 1 to 10 is Least Satisfied to Most Satsified
Table 2 – Survey Results of Customer Satisfaction
Among the requirements that the customers felt were most important are safety, reliability,
durability and low cost. Ease of operation, resistance to extreme weather and speed operation
also ranked high. Among the requirements that the customer felt they were least satisfied with in
their current product are accessibility of controls, speed of operation and ease of operation.
These are areas that can be greatly improved upon as the customer satisfaction with them is low.
Safety, energy efficiency, and reliability also ranked high among least satisfied factors. The
design for the automatic hydraulic jack addressed the shortcomings of the current vehicle jack
products while emphasizing on the factors that customers felt were the most important.
QFD RESULTS
The results from the customer survey were used to generate a QFD matrix from which the
relative importance percentage and the relative weight percentage are calculated. The complete
QFD matrix and results are present in Appendix C. Table 3 below lists the engineering
characteristics that are associated with the customer requirements. The engineering
characteristics are ranked from highest relative importance to least relative importance.
Rank
1
2
3
4
5
6
7
8
9
10
11
Relative Importance %
Engineering Characteristics
Relative Importance %
Power Source
24.00%
Material
16.00%
Safety/Status Indicator
12.00%
Cleaning/Maintenance
10.00%
Number of components
9.00%
Weight
7.00%
Size
6.00%
Guarding/Protection
6.00%
Manufacturability
4.00%
Actuation Method
3.00%
Installation Setup
3.00%
Rank 1 to 11 is Highest Relative Importance to Least
Table 3 - Relative Importance %
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The power source has the highest relative importance followed by material, safety, maintenance
and number of components in the top five rankings. The power source is important as it is what
will drive the whole automated mechanism. The material is important because it will affect the
reliability, durability, resistance to weather and cost of the product. Safety is also very important
as it is the primary reason for the development of this product.
The higher ranking engineering characteristics were given high importance in the design of the
product so that they may fulfill their corresponding customer requirements.
Table 4 below shows the customer requirements ranked in descending order of relative weight
percentage.
Relative Weight %
Rank Criteria Surveyed
Relative Weight %
1
Ease of Operation
14%
2
Accessibilty of Controls
12%
3
Energy Efficient
12%
4
Reliability
11%
5
Speed of Operation
11%
6
Durability
10%
7
Safety
10%
8
Resistance to Extreme Weather
9%
9
Ease of Maintenance
7%
10
Low Cost
5%
Rank 1 to 10 is Highest Weight to Lowest Weight
Table 4 - Relative Weight %
As the above results show, ease of operation, accessibility of controls and energy efficiency
have the highest relative weights. According to the survey results, ‘safety,’ ‘reliability’ and
‘durability’ are of the greatest importance to the customer. Even though the relative weight for
these factors are still relatively high, they do not require as great an improvement as the higher
ranking criteria in the relative weight table. The proposed automatic hydraulic jack will fulfill
the customer needs that have high relative weight.
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PRODUCT FEATURES AND OBJECTIVES
The following is list of product objectives and how they will be obtained or measured to ensure
that the goal of the project is met. The product objectives cover the hydraulic pump, motor,
shield, controls and wiring. The automatic hydraulic car jack is designed to be used on an even
surface to ensure safety and proper operation. The product features below are ranked in order of
highest customer importance to lowest customer importance.
1. Safety (4.92):
1.) Check valve to prevent back pressure
2.) Safety Factors in Design
3.) No external sharp edges
2. Reliability (4.92):
1.) Reliability of the device measured by component life and proper design criteria specified
in the following spec sheets:
-Air Bag Spec Sheet
-Air Compressor Spec Sheet
-Air Hose Spec Sheet
-Protective Shield Material Spec Sheet
-Mounting Hardware Material Spec Sheet
2.) The device will have a minimum lift capacity of 2000 lbs at 100 psi.
3. Durability (4.92):
1.) Device will not fail under repeated loads using the following safety factors:
-Aluminum/Steel Mounting Components (8)
-Airbag (1.5)
-Air Compressor (1.5)
-Air Hose (1.5)
4. Cost (4.88):
1.) Less than $200.
5. Speed of operation (4.84):
1.) The device will have an operating time less than 3 minutes.
6. Resistance to extreme weather conditions (4.84):
1.) Device is encased in water –tight protective shield.
2.) Protective shield is corrosion resistant.
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7. Ease of Operation (4.8):
1.) Removal of shield cover and air compressor initiation is only operation needed for
startup.
2.) Deflation is controlled by release valve.
8. Accessibility of Controls (4.64):
1.) Air compressor located in trunk.
9. Ease of Maintenance (4.52):
1.) Protective shield will keep components clean requiring only cleaning of external shield.
2.) Removal of protective shield for component access achieved by removing standard
screws and clamps.
10. Energy Efficient (4.08):
1.) Device will run entirely off of air compressor battery.
11. Ease of Manufacturing (N/A):
1.) Use off-the-shelf components.
2.) Manufacturing does not require complex joining or machining operations.
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CONCEPT GENERATION AND SELECTION
Hydraulic Car Jack Design:
The hydraulic car jack as shown in Figure 8 utilizes a hydraulic pump to raise the vehicle. The
hydraulic motor gets its power from the vehicles battery. The jack has to be manually placed
under the vehicle similar to regular car jack. Controls are used to engage the jack and stop it.
This concept has many drawbacks that do not make it an ideal product. First of all, the jack is
not attached to the vehicle and must be manually retrieved and placed. It also requires a flat
surface for proper engagement with the vehicle. The equipment needed to develop this jack can
be expensive as a relatively powerful hydraulic motor and pump is required along with the
necessary electronic controls. Storage of the jack can also be a problem as it has a relatively
large component size.
Figure 8 – Hydraulic Car Jack Design
Pneumatic Car Jack Design:
The pneumatic car jack as shown in Figure 9 uses a compressed air to inflate an airbag to raise
the vehicle. The compressed air is provided by an in-car air compressor. Air from the
compressor will be fed to airbag through an air hose and will pass the through a one-way air
check valve before infiltrating the airbag. This will prevent back pressure from the airbag into
the exhaust and allow the pressure to be maintained in the airbag. The pneumatic car jack also
has a few drawbacks. An air compressor can be an expensive device and will also require
permanent storage in the vehicle.
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Figure 9 – Pneumatic Car Jack Design
Exhaust Powered Car Jack Design:
The third design concept is an exhaust powered car jack as shown in Figure 10. The exhaust
gases from a combustion engine are fed into an airbag through a delivery hose. The delivery
hose has a one-way air check valve to prevent back pressure into the exhaust, while maintaining
pressure in the airbag. The airbag will be permanently attached to the underbody of the vehicle.
This makes the device safe as the operator does not have to retrieve the airbag and manually
place it under the vehicle.
Figure 10 – Exhaust Powered Car Jack Design
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Concept Selection:
Weighted Decision Matrix
Rating Scale
5 = Excellent 4 = Very Good 3 = Good 2 = Fair 1 = Poor
Concepts
Evaluation Criteria
Weight A: Hydraulic Score
B: Pneumatic
Score C: Exhaust Score
Safety
0.2
4
0.8
4
0.8
3
0.6
Reliability
0.2
4
0.8
5
1
4
0.8
Durability
0.2
5
1
4
0.8
3
0.6
Cost
0.125
2
0.25
3
0.375
5
0.625
Speed of Operation
0.075
3
0.225
3
0.225
2
0.15
Ease of Operation
0.075
3
0.225
3
0.225
4
0.3
Accessibility of Controls
0.05
3
0.15
3
0.15
4
0.2
Ease of Maintenance
0.05
2
0.1
4
0.2
4
0.2
Energy Efficient
0.05
3
0.15
3
0.15
5
0.25
Ease of Manufacturing
0.025
2
0.05
3
0.075
3
0.075
Total
1
3.75
4.00
3.80
Table 5 – Weighted Decision Matrix
A weighted decision matrix was conducted to see which of the three concepts has the best overall
design based on the evaluation criteria used for the customer survey. Table 5 shows the results
of the weighted decision matrix based on the total score for each concept based on the evaluation
criteria. The vehicle mounted pneumatic jack had the highest score and thus was the design
used. Some of the criterion where the pneumatic jack scored high were reliability, speed of
operation, accessibility of controls, ease of maintenance and ease of manufacturing
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FINAL DESIGN:
Vehicle Frame
Protective Shield
Air Hose
Airbag
Figure 11 – Final Design
Figure 11 shows the design for the vehicle mounted pneumatic jack. The jack assembly
consists of an airbag that is enclosed in a protective shield and cover. When the airbag is not in
use it is completely deflated with the shield cover closed underneath it. The airbag and shield
assembly is mounted underneath the vehicle to the same frame that is used with standard vehicle
jacks. The pneumatic jack is assembly is mounted to the frame of the vehicle using two
brackets. An air hose is routed from the airbag to an air compressor located inside the vehicle.
The pneumatic jack was designed such that it can lift an entire side of the vehicle using one jack.
The real world application of the design would require one such pneumatic jack on both the left
and right sides of the vehicle.
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DESIGN CALCULATIONS:
Test Vehicle:
For the purpose of this project, the vehicle which this pneumatic jack was designed and
implemented is a Mitsubishi Eclipse as shown in Figure 12. This pneumatic jack was designed
based on the specifications of this vehicle. Some of the important specifications needed in the
design are shown below.
1998 Mitsubishi Eclipse GS
Curb Weight = 2842 lb
Wheelbase = 98.8 in.
Figure 12 – Test Vehicle
Center of Gravity/Jack Location Calculations:
Since one whole side of the vehicle will be lifted using a single jack, it is important to find the
location on each side at which the weight distribution will be equal between the front and rear
sections of the vehicle. The center of gravity of the vehicle along its length is the ideal location
of the pneumatic jack. If the pneumatic is not located at the center of gravity, both tires on one
side may not rise off the ground at the same distances. The center of gravity of an average
production car is 14 to 22 inches off the ground. The center of gravity in the vertical direction is
not important as the vertical location of the jack will be bound by the frame of the vehicle. The
average production car has 60/40 front to rear weight distribution between the two axles.
Assumptions:
Wheel base = 99 in
Weight Distribution = 60/40 front to rear.
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CG (Front to Back direction) = 99 * 0.4 = 39.6 inches back from the front axle.
Figure 13 – Center of Gravity Location
CG (Front to Rear Direction) = 40 inches
back of the front axle
Figure 13 shows that the center of gravity along its length is located approximately 40 inches
rear of the front axle. The location of the jack along is width will be under the vehicles frame at
the edge of the vehicle, similar to the location where a standard vehicle jack is placed.
Design Load:
It is important to calculate the amount of load that the pneumatic will be lifting when in
operation on the test vehicle. The wheel-vehicle-airbag system work as a class 2 lever as shown
in Figure. The mechanical advantage of this lever system is used to calculate the input force
needed for a particular output force needed, which in this case is the 2000 lb design load. It is
assumed that the center of gravity of the vehicle is on or very close to the center line of the
vehicle along its length. Since the weight of the vehicle acts on its center of gravity and the input
force of the airbag is located at the edge of the vehicle, the input distance is approximately twice
that of the output distance. Figure 14 shows the relation between the load, lift point and the
fulcrum about which the vehicle is raised.
Assumptions:
Vehicle Total Weight = 3200 lb
Car Width = 68.5 in
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Analysis:
Vehicle-Tire-Airbag system work as a class 2 lever.
Mechanical Advantage of class 2 lever=
Input force = output force x output distance / input distance
= 3200 x 34.25 / 68.5 = 1600 lb
An additional 25% factor of safety in the design load.
Design Load = 2000 lb
Vehicle - Load
Pneumatic Jack - Force
Direction of Lift
Opposite Side Wheel - Fulcrum
Figure 14 – Wheel-Vehicle-Jack Lever System
The design load used throughout the design is 2000 lbs.
Shield Stress:
The shield is placed between the airbag upper plate and the vehicle frame. Figure shows the
location of shield case in relation to the airbag and vehicle frame. The shield undergoes bearing
load as it is compressed between the airbag upper bead plate and the vehicle frame. Figure 15
shows the projection of the bearing contact surface area of the vehicle frame on the shield case in
relation to the airbag upper plate. Figure 16 shows the free body diagram for the shield.
Assumptions:
Design Load = F =2000 lb
Design Factor = N = 8 (repeated load)
Vehicle Frame Thickness = t = 1 inch
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Figure 15 – Projected Bearing Contact Area
Contact surface area = 6.23 * 1 = 6.23 in2
For Aluminum:
Stress bd = 0.65 sy
Stress = f/a = 2000/6.23 = 321 psi
Design factor of 8 = Stress = 321 * 8 = 2568 psi
Required Yield Strength:
Stress bd= 1.6 * stress sy / 2.48
Sy = stress bd * 2.48 / 1.6 = 2568 * 2.48 / 1.6 = 3980.4 psi
Using Aluminum Sheet Metal:
Tensile yield strength of sheet metal (2014-0) = 10000 psi
Bearing Load = 2000 lb
Factor of Safety:
Factor of safety = 10000/3980.4 = 2.5
Figure 16 – Shield Stress FBD
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Vehicle Mounted Pneumatic Jack
Lower Plate Stress:
The lower plate is attached to the bottom of the airbag to
give it a larger base. The plate exhibits compressive
stress. Figure 17 shows the free body diagram for the
lower plate.
FAIZAN NASIR
Bearing Load = 2000 lb
Assumptions:
Load = 2000 lb
Design factor = 8
Plate Stress:
Plate surface area = 4 x 4 =16 in2
Stress = F/A = 2000/16 = 125 psi
Design factor of 8 = Stress = 125 * 8 = 1000 psi
Tensile strength of sheet metal (2014-0) = 10000 psi
Figure 17 – Lower Plate Stress FB
Factor of Safety:
Factor of safety = 10000/1000 = 10
Angle of Airbag (Shear):
When the airbag is inflated, it expands in the vertical direction. The point at which the airbag
contacts the vehicle frame is fixed. As the airbag is released from the shield, it expands pushing
into the ground below. The load of the vehicle prevents the airbag from moving along the
ground. Since the wheel-vehicle-airbag system work as a lever, the air bag will not be at an
exactly 90 degree angle with the ground below. Variations in the level and height of the ground
below will further affect the angle of the airbag. This angle is calculated using basic geometric
principles assuming that only distance changing during the lifting process is that associated
directly with the airbag. The calculated angle is too small to exhibit any significant shearing
force. The airbag is designed to be used in such lever type applications and can withstand the
minimal shearing force.
Mounting Stresses:
There are two brackets holding the shield and airbag assembly to the bottom of the vehicle. The
weight of the airbag is 7.5 lbs and the weight of all the sheet metal used in the fabrication of the
shield and mounting brackets is approximately 3 lbs. The total weight of the assembly is no
more than 11 lbs. This is a very low load and the stress forces on the mounting brackets and
hardware are negligible.
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COMPONENT DESIGN/SELECTION:
Airbag Selection:
After experimentation, the distance required to raise the vehicle off of the ground in order
for the wheels on one side of the vehicle to come off the ground is 9 inches. The design load is
2000 lbs; this is the minimum amount of weight the airbag should be able to lift. The ideal
airbag will have a minimum 9 inch extended height and lowest compressed height. The diameter
of the airbag should also be kept to a minimum so that it will take up the minimum amount of
space under the vehicle. Firestone Airstroke Actuators airbags are made for vehicle suspension
and industrial applications. The Firestone Airstroke Actuator series has several pneumatic
airbags that meet these design criteria. The convoluted air spring with the crimped bead plate
has the ideal profile for the pneumatic jack as shown in Figure 18. The convoluted bellows have
the smallest compressed heights combined with the bead plates that have a small profile. The
blind mounting nut also allow for mounting hardware that protrude out the least from the upper
bead plate. There are several different types of bead plate styles available, however the type 1
style as seen in Figure 19 is the most common and fits the design criteria. There are several
different types of material configurations for the airbag. The different configurations are made
for different temperature ranges. The standard material type shown in Figure 20 has a range
from -37C to 57C, which is adequate for this application. From the selection guide shown in
Figure 21, the double convoluted style #20 airbag with the type 1 bead plate fits the criteria for
this design. The selection guide shows the force delivered by the airbag at 80 psi and in full
extension to be 1770 lbs. However for 100 psi of air pressure, the force is estimated to be
approximately 2212 lbs, more than the design load.
Figure 18 – Convoluted Air Spring
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Figure 19 – Type 1 Bead Design
FAIZAN NASIR
Figure 20 – Airbag Material Selection
Figure 21 – Airbag Selection Chart
Figure shows the specification sheet for the Firestone Actuator #20 airbag. For this design
purpose, assembly order no. W01-358-6910 was used. Figure shows the actual airbag that was
used in this design.
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Figure 22 – Airbag Force Table
According to the Force table shown in Figure 22, at a design height of 9 inches and 100 psi of air
pressure, the airbag delivers a force of 2380 lbs. This is more than adequate for the design load
of 2000 lbs. Figure 23 shows the actual airbag that was used in the design.
Figure 23 – Firestone Airbag
Air Compressor Selection:
An air compressor is required to provide compressed air that will inflate the airbag. The airbag
requires an internal pressure 100 psi to raise the design load to the maximum height of 9 inches.
The Campbell Hausfeld 12VDC Portable Air Compressor was used in this design. This air
compressor can deliver a maximum air pressure of 125 psi and1 cfm of free air at 90 psi. The air
compressor utilizes a rechargeable battery and the battery charger is provided with the product.
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The air compressor is relatively lightweight as it only weighs 9 lbs. The size of this air
compressor is approximately 11x8x5, which makes it compact and easy to store. An air hose is
also provided, which includes a coupler plug fitting for connecting to the air compressor. Figure
24 shows the air compressor and the accessories it is provided with.
Figure 24 – Campbell Hausfeld Air Compressor
Air Hose:
The air hose provided with the air compressor was shorter than the required length and not
flexible enough to be routed effectively under the vehicle. A general duty multi-purpose EPDM
Air Hose with a 1/4 inch I.D as shown in Figure 25 was used for the compressed air delivery.
The air hose comes with ¼ inch NPT male fittings and has a total length of 25 feet. The air hose
is rated at 200 psi, more than adequate as the airbag only requires 100 psi and the air compressor
has a maximum air pressure of 125 psi.
Figure 25 – EDPM Air Hose
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Shield/Mounting Material:
The material used for the airbag shield case, cover and mounting brackets is 2014-0 Aluminum
sheet metal. 2014-0 Aluminum is suitable for all the stresses calculated for the various sections
of its design applications. 2014-0 Aluminum does not exhibit excellent corrosion resistance
properties as other Aluminum alloys. However it is readily available at a relatively low cost.
The final shield and mounting assembly will be painted with a high grade automotive paint
protecting the Aluminum from possible corrosion.
FABRICATION:
Shield/Mounting Assembly:
Figure 26 – Shield/Mounting Assembly
The complete shield and mounting assembly is shown in Figure 26. The shield case was
designed to be of the smallest size that can completely enclose the airbag. Enclosing the airbag
completely will protect it from the environment when it is not in use. The smallest size for the
shield casing was desired so that it takes up the minimal amount of room when mounted under
the vehicle. All components were fabricated from (2014-0) Aluminum Sheet Metal. Using the
same material for all the components in the assembly kept material costs to a minimum. Figure
27 shows the side view of the shield and mounting assembly.
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Figure 27 – Shield/Mounting Assembly Side View
Shield Case:
Figure 28 – Shield Case Bottom
Figure 29 – Shield Case Top
Figure 28 shows the bottom side shield case which will enclose the airbag completely when
it is not in use. 2014-0 sheet metal was cut into an 18x20 sheet using a sheering metal cutter.
Figure 29 shows the top side of the shield case. After the sheet metal was cut to the required
size, it was bent into an open box form using a magnetic hand metal bender. The excess 1 inch
on two sides of the box were bent to form grooves. These grooves will hold the shield cover.
In order to close and reinforce the corners of the box, brackets were welded to the inside of
all for corners as shown in Figure 31. The brackets shown in Figure 30 were formed from the
same 2014-0 sheet metal material used for the shield case. Four 1x2 inch rectangular pieces
were cut and then bent along the centerline to form 90 degree brackets. The brackets were spotwelded to the edge of the shield case at each corner as shown in Figure 17. Multiple spot-welds
were made on each side of the bracket to ensure a reliable and durable joint.
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Figure 30 – Corner Brackets
FAIZAN NASIR
Figure 31 – Corner Brackets Welded
Rear Mounting Bracket:
Figure 32 – Rear Mounting Bracket
The rear mounting bracket as shown in Figure 32 is formed from the same 2014-0
Aluminum sheet metal material used in the shield case fabrication. The cuts were made using a
hand operated sheer metal cutter and the 90 degree bents were made using a hand operated
magnetic metal bender.
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Figure 33 – Rear Mounting Bracket Welded
The rear mounting bracket is attached to rear side of the shield case as shown in Figure 33.
The bracket is spot-welded with both the case and bracket upper surfaces parallel and on the
same plane. Multiple spot-welds were made to ensure a rigid and durable joint.
Front Mounting Bracket:
Figure 34 – Front Mounting Bracket
The front mounting bracket as shown in Figure 34 is formed from the same 2014-0
Aluminum sheet metal material used in the shield case fabrication. The bracket was bent to an
internal angle of approximately 130 degrees. This angle ensured that face of the bracket attached
to the vehicle’s frame was parallel to that frame. The two surfaces needed to be parallel in order
to ensure a proper and tight bolt fit. The sheet metal was cut using a hand operated sheer metal
cutter and the bents were made using a hand operated magnetic metal bender. A hole of ¼ in
diameter was drilled along the center line of the bracket using an automated step-driller. A ¼
inch diameter hole gives adequate movement for the bolt so that it can be easily inserted and
removed for installation and maintenance.
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Figure 35 – Front Mounting Bracket Welded
The front mounting bracket was attached to the front side of the shield case as shown in
Figure 35. The bracket is located along the center of the shield case with 3 inches of distance
from the top of the bracket to the shield case surface. Several spot-welds were made to join the
two surfaces and to ensure a rigid and reliable joint.
Shield Case Upper Bracket:
Figure 36 – Shield Case Upper Bracket
Figure 37 - Shield Case Upper Bracket Welded
The shield case upper bracket was made to give rigidity to the case when attached under the
vehicle. Aluminum sheet metal was cut into a 10 inch by 1.85 inch strip. The sheet metal strip
was then bent at a 90 degree angle along its length so that one face of bracket would have a 1
inch width and the other 0.85 inch as shown in Figure 36. The 1 inch width face was spotwelded to exterior of shield case on the top side. The 0.85 inch face perpendicular to the shield
case top surface was designed so that it would not interfere with vehicle’s underbody when in
contact with the frame at which the vehicle is raised. The shield case upper bracket is attached to
the upper surface of the shield case on its outer surface along the center as shown in Figure 37.
The two mating surfaces were spot-welded along the brackets entire length to ensure a rigid and
reliable joint.
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Shield Cover:
Figure 38 – Shield Cover
Figure 39 – Inserted Shield Cover
As shown in Figure 38, the shield cover is a flat piece of sheet metal used to completely
close the shield case. The shield cover is opened when the airbag is in use and closed when not
in operation. The shield cover is made from the same 2014-0 Aluminum sheet metal material
used for the shield case. The shield cover was cut into the required dimensions needed to
completely close the shield case as shown in Figure 39. The corners and edges of the shield
cover are rounded using a grinder and a file for safety reasons. Since the operator will be
grabbing the cover in order to open and close it, the rounded edges will prevent any injury.
When the shield cover is closed, it forms a tight fit with the shield case preventing water or
debris from entering the shield case and potentially harming the airbag.
Lower Plate:
Figure 40 – Lower Plate
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The lower plate as shown in Figure 40 is attached to the base of the airbag to give it a wider
and more stable base when actuated. The plate is formed from 2014-0 Aluminum sheet metal
material and is cut into a 4x4 inch flat plate. The edges and corners of the lower plate rounded
using a file. This will ensure that the operator is not harmed when compressing the airbag in
order to close the shield cover under it.
SYSTEM ASSEMBLY
Airbag-Shield Joining:
Figure 41 – Airbag-Shield Joining
Figure 42 – Airbag-Shield Bolts
The airbag is mounted to the shield using a 3/8"-16 x 1-1/2" Hollow Bolt shown in Figure
42. Figure 41 shows the location of the hole drilled in the shield case through which the bolt will
be inserted. The bolt along with a hardened ¾ inch steel washer will be used to join the shield
case to the airbag. Using bolts and washers to attach the airbag to the shield case rather than a
permanent joint allows for easier installation and removal during maintenance. The bolts are
standard grade 2 bolts as there are no major stress forces acting on the bolt or shield at the hole
location.
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Shield Mounting:
Mounting Locations
Figure 43 – Shield Mounting Locations:
As shown in Figure 43, the airbag-shield system is mounted to the underbody vehicle frame
at two locations. In order to mount the pneumatic jack system, the side skirt of the vehicle had to
be removed to make the vehicle frame visible. The mounting location of the front mounting
bracket was also hidden under the side skirt of the vehicle. Removal of the side skirt was
achieved by unscrewing several bolts and removing clips along the bottom of the vehicle. The
shield case upper bracket also serves as guide for the location and mounting of the entire jack
assembly. Figure 44 shows the rear mounting bracket attached to the frame underneath the
vehicle using a clamp. The two parts are held together by tightening a bolt on the clamp.
Figure 44 – Shield Mounting Rear view
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Figure 45 – Shield Mounting Front View
Figure 45 shows the location of the front mounting bracket and its location in relation to the
vehicle. A ¼ inch hole was drilled in the side frame of the vehicle along its bottom corner. The
hole was drilled at the center of gravity of the vehicle location calculated earlier to ensure proper
weight distribution when the vehicle is being lifted. A ¼ inch Hex bolt along with a ½ inch
spacer and a 1 inch washer were used to mate the front mounting bracket to the vehicle’s frame
as shown in Figure 46.
Figure 46 – Front Mounting Bracket Bolt Location
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Lower Plate Mounting:
Figure 47 – Lower Plate Mounting
The lower plate was attached to the bottom plate of the airbag as shown in Figure 47. In
order to ensure a flat and level surface on the lower plate, it was welded to the bottom plate of
the airbag. J-B Weld, a cold weld epoxy solution, was applied to the contacting surfaces
between the lower plate and bottom plate of the airbag. The cold weld epoxy ensures a durable,
reliable and waterproof joint between the two mating surfaces. Using the cold weld epoxy
provides a permanent joint between the two surfaces while keeping costs to a minimum.
Air Hose/Fittings
Figure 48 – Air Hose Fittings
Figure 49 – Elbow Fitting
A ¼ inch I.D air hose as shown in Figure 48 was used to deliver air from the compressor to
the airbag jack system located under the vehicle. The air hose was cut to the required 15 feet
length from the airbag to the compressor. The fitting used to attach the air hose to the air
compressor was a ¼ inch I.D hose barb with a ¼ inch male NPT fitting. The ¼ inch male fitting
was screwed into a ¼ inch coupler fitting available with the air compressor. The fitting used to
attach the air hose to the airbag was a ¼ inch I.D Hose barb with a 1/8 inch male NPT fitting
elbow as shown in Figure 49. The elbow fitting was required in this case because of the small
gap between the airbag and vehicle’s frame. A ¼ inch hose clamp was tightened on the air hose
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at the both fitting joints to ensure no leakages or dislodging of the air hose. Figure 50 shows the
location of elbow hose barb fitting joining the air hose and air bag.
Figure 50 – Air Hose-Airbag Fitting
Air Compressor Mounting:
Figure 51 – Air Compressor Mounting
The air compressor is located in the trunk of the vehicle behind the rear driver side seat as
shown in Figure 51. A strap provided with the air compressor is used to hold the air compressor
firmly to the back of the rear seat. This will ensure that the air compressor will not be damaged
when the vehicle is in operation. The air compressor is visible in plain sight and easily
accessible from the rear of the vehicle so that the operator can easily start and stop the air
compressor. The rechargeable battery and the air pressure discharge coupler are also within
accessible range of the operator.
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Air Hose Routing:
Figure 52 – Air Hose Routing
The air hose is routed under the vehicle from the airbag to the air compressor located in the
trunk of the vehicle. Clips were used to attach the air hose to a brake fluid line that ran
underneath the vehicle as shown in Figure 52. The air hose was then routed over the rear axle
and inserted into the trunk of the vehicle through a hole at the bottom of the trunk. The general
purpose of hole located at the bottom of the trunk that is closed using a rubber plug is to drain
water or any other liquid that may have accumulated in the trunk. A hole of the approximately
the same diameter of the air hose was cut into the rubber plug for insertion of the air hose and a
tight fit. The air hose was then connected to the air compressor located in the trunk. The length
of the air hose was tightened underneath the vehicle to ensure no dangling of the air hose.
OPERATION PROCESS
1. Open shield cover.
- The operator slides the shield cover outwards from the shield case in order to release the
airbag.
2. Start air compressor to raise vehicle.
-The air compressor in the trunk of the vehicle is started.
3. Stop air compressor once desired height achieved.
- The air pressure inside the airbag in will increase until enough pressure to raise the vehicle is
achieved. Once the vehicle has risen to the desired height, the air compressor is shut off. The air
compressor will maintain the air pressure inside the airbag, keeping the vehicle aloft. Figure
shows the airbag extended after the shield cover has been opened and the compressor started.
4. Conduct task needed.
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- The operator then can conduct any required task such as changing a flat tire.
5. Remove airline fitting from compressor to discharge pressure.
- Once the desired task has been conducted, the airbag needs to be deflated in order to lower the
vehicle. In order to release the air pressure, the coupler fitting connecting the air compressor and
air hose is removed. The air pressure will be released from the airbag, slowly lowering the
vehicle in the process.
6. Close Shield Cover.
- Once all the excess pressure has released from the airbag, the operator lifts the airbag and
slides the shield cover under it. The airbag only requires 7 lbs of force to be compressed in order
for the shield cover to close under it. This force is relatively small and will not require much
effort from the operator. Figure shows the shield case, with the airbag deflated inside it and the
shield cover closed.
After experimenting with the pneumatic jack on several occasions the lifting operation time
is approximately 1.5 to 2 minutes. The lifting operation time is from when the shield cover is
removed to when both wheels on one side of the vehicle have been raised from the ground. The
variability in the lifting operation time depends on the level and distance of the ground at the
contact point with the pneumatic jack. Figure 53 shows the deflated position of the airbag when
it is not in use and shield cover is closed. Figure 54 shows the inflated position of the airbag
when it is being fed compressed air.
Figure 53 – Airbag Deflated Position
Figure 54 – Airbag Inflated Position
TESTING:
Air-Leak Test:
The first test conducted on the pneumatic jack system was an air-leak test. The purpose of the
air-leak test was to ensure that the system is able to build and maintain air pressure without any
leakage. The two main connections in the system are the airbag-elbow-hose and the hosecoupler-compressor fittings. In order to test these fittings, a soap-water mixture was placed on
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the various connections. In the event of an air leak, the mixture would be disturbed giving
evidence of leakage. The air compressor was started and the airbag was inflated to the maximum
design pressure of 100 psi. Once the pressure was achieved, the air compressor was shut off.
The pressure inside the system was maintained for 30 minutes and the fittings were inspected for
air leaks during that time period. After the 30 minutes and constant visual inspection, no airleaks were reported.
Load-Test:
The second critical test of the pneumatic jack system was the load-test. After successful
completion of the air-leak test, the system was placed under the test vehicle. Weights were
added to the vehicle to achieve the design load of 2000 lbs. The air compressor was started and
vehicle was raised to the maximum height achievable by the airbag. After the desired maximum
height was achieved at the design pressure of 100 psi, the distance of the raised wheels from the
ground were measured and recorded. The air compressor was shut off and the vehicle was kept
raised for 2 hours. After 2 hours, the distance of the raised wheels from the ground were
measured and compared to the initial readings. The pneumatic jack system successfully
completed the load test as there was no significant change in the height of the wheels from the
ground.
PROJECT MANAGEMENT
Schedule:
The project schedule begins on November 10, 2008 with vehicle jack concept development and
ends on June 5th when the Final Design Report is due. The complete schedule is present in
Appendix D.
Project Milestone Dates:
Design Freeze
Oral Design Presentation
Design Report Due
Demo/Proof of Design
Tech Expo
Oral Presentation
Final Report Due
February 2nd
March 2nd
March 9th
April 27th
May 7th
May 27th
June 1st
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Projected v.s Actual Schedule
Task
Projected Date
Actual Date
Car Jack Concept Development
1/4/2009
1/4/2009
Preliminary Design
1/18/2009
1/18/2009
Design Freeze
2/2/2009
2/2/2009
Final Design
3/1/2009
4/15/2009
Oral Design Presentation
3/2/2009
3/2/2009
Winter Design Report
4/12/2009
4/12/2009
Pneumatic Jack Fabrication
4/19/2009
5/1/2009
Assembly/Testing
4/23/2009
5/5/2009
Tech Expo
5/7/2009
5/7/2009
Final Oral Presentation
5/29/2009
5/29/2009
Final Design Report
6/1/2009
6/1/2009
Table 5 – Schedule
Table 5 shows the major tasks throughout the project along with their projected and actual
dates of completion. There were three crucial instances when then projected dates were not met.
Firstly the final design was late by about two weeks. This was because of several major design
changes that were made throughout the design process. Initially a hydraulic jack was proposed,
after which an exhaust driven jack was proposed. After several design iterations, the final design
was based on the pneumatic system. Because of the delay in the final design for the project, the
fabrications as well as assembly were delayed. The fabrication of the shield was on time;
however the airbag took longer than expected to arrive. The delay in the arrival of the airbag
also added to the delay in testing process. Other than these three criteria, all other tasks were met
on time including the CAS Tech Expo, Oral Presentations and Final Design Report. A complete
detailed schedule is shown in Appendix D.
Budget:
The budget expenses for this project will be covered by the designer, Faizan Nasir. Budget
expenses include all parts and equipment required for manufacturing. All machining and joining
process will be conducted in the CAS lab with raw materials provided by the designer. The
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materials and equipment included in the budget include airbag, air compressor, air hose,
protective shield, mounting hardware, fittings and other miscellaneous hardware. The initial
proposed design was a hydraulic jack system, for which the budget was $325. The final design
that was implemented was the pneumatic jack which had an actual budget of about $346. Even
though the final budget is higher than the initial, it is merited because the pneumatic jack has
several advantages over the hydraulic design. The large portion of the final cost is due to two
components, the airbag and the air compressor. The airbag cost approximately $170 whereas he
airbag cost about $95. The rest of the budget consisted mainly of mounting and shield materials
as well as miscellaneous hardware. The complete budget is present in Appendix E.
Recommendations and Conclusions:
Overall the project from conception to design and finally to implementation went fairly well.
There were some drawbacks in the design and fabrication process; however the project was
completed on time. After using the product several times, there are some concerns that should be
dealt with before the product is to be mass produced for the public. The ground clearance of the
vehicle is affected by the airbag-shield assembly as it protrudes from beneath the car. On the test
car for which this particular pneumatic jack was developed, the ground clearance was reduced by
4 inches. This can be hazardous as altering the ground clearance can pose safety hazards while
the car is moving. In order to counter this problem, it is recommended that the airbag-shield
assembly be mounted at a higher point on the vehicle. This may require extensive modifications
to the vehicle which can be costly. One of the purposes of this project was to further automate
the process of raising and lowering a vehicle. When using the vehicle mounted pneumatic jack,
the operator is still required to go to the airbag and slide opens the shield cover. Automation of
this process, where a servo motor can be used to automatically open and close the shield would
further reduce safety hazards and operation time. The vehicle mounted pneumatic jack will
drastically reduce safety hazards posed by standard and currently available aftermarket vehicle
jacks. The process of raising and lowering a vehicle can be fully automated reducing the safety
hazard and making the process convenient for the operator. The vehicle mounted pneumatic jack
will accomplish this goal at a reasonable price.
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REFERENCES
1. All Products. 12v Electric Car Special Hydraulic Jack. Allproducts.com.
http://www.allproducts.com/manufacture100/wtonet/product1.html November 5, 2008.
2. Jack Co Ltd. Economic DC 12v Motorized Auto Jack. www.himfr.com.
http://www.himfr.com/d-p11451398252435225Economic_DC_12v_Motorized_Auto_Jack_%3A_JM-2000/ November 5, 2008.
3. Manual Jack. Shanghai Yicheng Auto Inspection Device Science. www.himfr.com
http://www.himfr.com/d-p1124538896002625-Hydraulic_Jack/
4. Sharp, Junior Loyd. Easy Lift Hydraulic Jack Conversion Kit. 20040104381 USA Nov 21,
2003. [Online]http://www.freepatentsonline.com/y2004/0104381.html. United States Patent
5. Instajack. Instajack and Instawrench Combo. Coolparts.com.
http://www.coolparts.com/products/InstaJack_and_InstaWrench_Combo-67189-16.html
November 5, 2008.
6. Car Jack. Car Jack PreliminaryAnalysis. Design decisions Wiki.
http://ddl.me.cmu.edu/ddwiki/index.php/Car_Jack_Preliminary_Analysis November 5, 2008.
7. Exhaust Jack. Alibaba.com November 5, 2008 http://www.alibaba.com/productgs/211872803/Exhaust_jack_air_jack_car_jack.html
8. Mott. Applied Strength of Materials. Textbook. Design Factors
39
APPENDIX A – RESEARCH
Interview with customer 9/29/08.
Saad Saleem. Car owner. (513)371-2215
Recently had a flat tire requiring him to raise car using manual jack.
Labor intensive and time consuming.
Automatic Hydraulic Jack would be safer and more efficient.
http://www.kawachibazar.co
m/electrical- electronicitems.html
9/28/08 Automatic Car Jack
Kawachibazar.com
Automated operation
Requires manual placement
Requires flat surface.
Remote cord short.
Has to be ordered online.
Performance Parameters
• Lifting Capacity 1 /1.5/2ton
• Supply Voltage 12V
• Rated Current 10A
• Lifting Height 120MM--350MM
• Working Temperature -40 + 90
• Net Weight 4KG
Appendix A1
Automated operation
High lift capacity
High lift range
Storage case
Requires manual placement
Requires flat surface
InstaJack Instant 12v Automatic Car Jack
LIFT CAPACITY: Vehicles up to3.5 TONS
LIFT RANGE: 5” to 17.5”
http://www.instajack.com/instajack.html
9/28/08 InstaJack Automatic Car Jack
Instajack.com
JK100 : InstaJACK™
UPC Code: 831541551009
JK 100 Includes:
1– 12V DC InstaJACK™
2– 15-amp replacement fuses
1– Heavy-Duty Storage Case
http://www.allproducts.com/manufacture100/w
tonet/product1.html
9/28/09 12v Car Hydraulic Jack
Allproducts.com
Automated operation
Low height range
Low weight capacity
Compact size
Requires flat surface
Requires manual placement
Model NO: DYQ-1130
12V electric cars special hydraulic jack
Mini Height: 130 MM
Max Height: 300 MM
Rated Voltage: 12 V
Rated Current: 10 A
Lifting Time: 30 second
Max lifting weight: 1000KG
Applicable for: car less than 2000 KG
Weight: 3.3 KG
Size: 17CM x 14 CM x 13.5 CM
Protection: if overload, current will be off automatic,it can be
continue to work automatic after 5 second
Packing: shaped plastic foam box
Inner box: 22CM x 18CM x 18CM
ourter carton: 24CM x 39CM x 39CM
Appendix A2
http://www.himfr.com/d-p11451398252435225Economic_DC_12v_Motorized_Auto_Jack_%3A_JM-2000/
9/28/09 Economic DC 12v Motorized Auto Jack
Himfr.com
Automated operation
Slow operating time
Direct battery power compatible
Requires flat surface
Requires manual placement
Voltage : D.C 12V~14V (Powered by Cigar Lighter or Battery)
Current : 15 Amp
Operating Method : Vertical Lift Screw Operating Type
Lifting Range : Max. 156 mm
Minimum Height : 156mm
Vehicle Weight : Within 2,000kg
Operating Time: Around 2 Mins
JACK CO LTD
Model no. Cy-130 12v impact wrench with LED light
(powered on car cigar lighter)Output square shaft:1/2 (13mm)
Max torque:350nm/250 ft. Lb
No-load speed:5300 RPM
Appendix A3
http://cn-autoline.manufacturer.globalsources.com
/si/6008814312487/pdtl/Car-emergency/1008825804/ HydraulicFloor-Jack.htm
9/28/08 Hydraulic Floor Jack
Autoline International Trading Co Ltd
Manual operation
Manual placement
Large size
Large weight
Not easily storable
2T Hydraulic Floor Jack with 135 to 340mm Lift and GS
Approved
Model Number:140123
Key Specifications/Special Features:
•
•
•
2T capacity
Lift: 135 to 340mm
GS and TUV approvals
Easy Lift Hydraulic Conversion Jack Kit
Patent: United States Patent Application 20040104381
http://www.freepatentsonline.com/y2004/0104381.
html
10/15/08 Easy Lift Hydraulic Conversion Jack Kit
Jack not attached to vehicle
Requires manual placement
Large setup
Not easily storable
Abstract: A hydraulic conversion kit designed to convert a
manual jack to hydraulic, with the use of a 12V hydraulic
pump, special mounting brackets, and a hydraulic motor. This
changes the manual jack to the ease of push button
operation.
Inventors: Sharp, Junior Loyd (Fair Grove, MO, US)
Appendix A4
Vehicle Mounted Hydraulic Jack System
Patent number: 6991221
Issue date: Jan 31, 2006
Inventor: Daniel G. Rodriguez
Application number: 10/908,039
Expensive setup
Complex system
Not easily manufactured
http://www.google.com/patents?id
M_UiAAAAEBAJ &dq=automatic
+hydraulic+car+jackVehicle mounted hydraulic
jack system
10/15/08 Vehicle Mounted Hydraulic Jack
System
Abstract: A vehicle jack system attachable to a vehicle for
lifting portions of the vehicle. The system includes at least
one hydraulically operated jack pivotally mounted to the
associated vehicle. A hydraulic positioning assembly extends
between the jack and the vehicle to effect a pivoting of the
jack into either a horizontal position for storage, or a vertical
position for operation thereof. A solenoid arrangement
facilitates a controlled distribution of hydraulic fluid from a
pressure source to a plurality of such jacks mounted around
the vehicle. An alternate embodiment of the present includes
a ground engaging ski for permitting translation of the vehicle
over an icy surface, and a locking assembly for securing both
a longitudinal and angular position of each jack.
Exhaust Powered Jack
Manual Placement Required
Large Airbag Size
The exhaust powered airbag uses exhaust gasses from the
vehicles to inflate and airbag which is used to raise the vehicle.
The airbag is manually placed under the vehicle and a hose is
inserted into the exhaust pipe of the vehicle. The drawback to
this design is that the airbag is very large in size and has to be
manually placed under the vehicle. Thus the operator is still in
harm’s way as the airbag is being placed.
Appendix A5
APPENDIX B – CUSTOMER SURVEY AND RESULTS
Automated Hydraulic Car Jack
Customer Survey with Results
How important is each feature to you for the design of the automated hydraulic car jack?
Please circle the appropriate answer.
1 = low importance
5 = high importance
Avg
Ease of maintenance
1
2
3(1)
4(10)
5(14)
N/A
4.5
Ease of operation
1
2
3
4(5)
5(20)
N/A
4.8
Reliability
1
2
3
4(2)
5(23)
N/A
4.9
Durability
1
2
3
4(2)
5(23)
N/A
4.9
Resistance to extreme weather
1
2
3(1)
4(2)
5(22)
N/A
4.8
Low Cost
1
2
3
4(3)
5(22)
N/A
4.9
Safety
1
2
3
4(2)
5(23)
N/A
4.9
Speed of operation
1
2
3
4(4)
5(21)
N/A
4.8
Energy Efficient
1
2
3(9)
4(5)
5(11)
N/A
3.1
Accessibility of Controls
1
2
3(3)
4(3)
5(19)
N/A
4.6
How satisfied are you with your current car jack?
Please circle the appropriate answer.
1 = Unsatisfied
5 = Very Satisfied
Avg
Ease of maintenance
1
2
3(3)
4(12)
5(10) N/A
4.3
Ease of operation
1
2(7)
3(15)
4(3)
5
N/A
2.8
Reliability
1
2(2)
3(5)
4(18)
5
N/A
3.6
Durability
1
2
3(4)
4(20)
5(1)
N/A
3.9
Resistance to extreme weather
1
2
3(2)
4(21)
5(2)
N/A
4.0
Low Cost
1
2
3(2)
4(6)
5(17) N/A
4.6
Safety
1
2(4)
3(18)
4(3)
5
N/A
3.0
Speed of operation
1
2(21)
3(3)
4(1)
5
N/A
2.2
Energy Efficient
1
2
3(6)
4
5
N/A(19) 3.0
Accessibility of Controls
1(19)
2(3)
3(3)
4
5
How much will you be willing to pay for an automated hydraulic car jack?
($5 - $ 15)
($25 - $50)(4)
($50 - $100)(19)
($100 - $200)(2) ($200 +)
N/A
1.4
Appendix B1
9
4.52
3
3
4.8
3
3
3
4.92
9
3
4.92
3
9
4.84
3
9
1
9
4.88
3
3
9
3
3 4.92
9
4.84
3
9 4.64
3
9
4.08
0.64 0.95 0.70 1.67 0.27 2.46 0.98 1.19 0.59 0.44 0.29 10.2
0.06 0.09 0.07 0.16 0.03 0.24 0.10 0.12 0.06 0.04 0.03
1
1
1
1
1
1
1
1
1
1
4.3
2.7
3.5
3.7
4
4.6
3.1
2.3
3
1.6
4.6
5
5
5
5
3
4
3.5
5
3
1.1
1.9
1.4
1.4
1.3
0.7
1.3
1.5
1.7
1.9
4.8
8.9
7.0
6.6
6.1
3.2
6.3
7.4
7.7
7.7
65.7
0.07
0.14
0.11
0.10
0.09
0.05
0.10
0.11
0.12
0.12
1.00
Relative weight %
Improvement ratio
Planned
Current Satisfaction
Sales Point
Customer importance
Actuation method
Manufacturability
Guarding/Protection
Safety/Status Indicator
Cleaning/Maintenance
Power
Material
Installation Setup
3
Relative weight
1
3
3
Modified Importance
Ease of maintenance
Ease of operation
Reliability
Durability
Resistance to weather
Low cost
Safety
Speed of operation
Accessibilty of controls
Energy Efficient
Abs. importance
Rel. importance
Weight
Size
Automatic Hydraulic Car
Jack QFD
Number of components
APPENDIX C – QUALITY FUNTION DEPLOYMENT ANALYSIS
7%
14%
11%
10%
9%
5%
10%
11%
12%
12%
*Sales Point – 1’s used to donate exclusion
of sales point from calculations.
Appendix C1
Task
Proof of Design Contract
Car Jack Concept Development
Choose Best Concept for Jack
Preliminary Design Work
Jack Design
1. Airbag Design
2. Shield Design
3. Air Hose routing / Fitting Design
4. Mounting Design
Design Freeze
Component Selection
Car jack BOM
Final Car Jack Design
Oral Design Presentation
Design Report
Order Jack Components
Exhaust Jack Component Fabrication
1. Airbag
2. Shield
3. Mounting
4. Hose/Fittings
Assembly
Testing
Modification
Final Test
Demonstration of Proof of Design
CAS Tech Expo
Final Design Report Revision
Oral Presentation
Final Design Report
6/1 - 6/7
5/25 - 5/31
5/18 - 5/24
5/11 - 5/17
5/4 - 5/10
4/27 - 5/3
4/20 - 4/26
4/13 - 4/19
4/6 - 4/12
3/30 - 4/5
3/23 - 3/29
3/16 - 3/22
3/9 - 3/15
3/2 - 3/8
2/23 - 3/1
2/16 - 2/22
2/9 - 2/15
2/2 - 2/8
1/26 - 2/1
1/19 - 1/25
1/12 - 1/18
1/5 - 1/11
12/29 - 1/4
12/15 - 12/21
12/8/ - 12/14
12/1 - 12/7
Faizan Nasir Vehicle Mounted
Pneumatic Jack Schedule
(begin every Monday)
11/24 - 11/30
APPENDIX D – SCHEDULE
4
11
18
1
15
22
22
1
2
8
15
29
3
19
12
19
5
12
12
16
23
23
26
27
7
31
29
5
Appendix D1
APPENDIX E – PRODUCT OBJECTIVE MEAUSUREMENT AND RESULTS
Product Objective Measurement and Results
Product Objective
Safety
Criteria
Check Valve
Design in Factors
No Sharp Edges
Reliability
Airbag Spec
Air Compressor Spec
Air Hose Spec
Fittings Spec
Shield/Mounting Material Spec
Durability
Design Factors : Aluminum: 8
Airbag : 1.5
Air Comrpessor : 1.5
Air Hose : 1.5
Cost
Less than $200
Speed of Operation
Less than 3 mins
Resistance to Extreme Weather Water-tight shield
Corrosion resistance
Ease of Operation
Removal of shield only manual operation
Deflation through release valve
Accessibility of Controls
Air compressor located in trunk
Ease of Maintenance
Shield keeps components clean
Easy Removal
Energy Efficient
Run off air compressor battery
Ease of Manufacturing
Use off-the-shelf components
No complex manufacturing
Measurement
In air compressor
Load-test
Corners grinded/rounded
Design within spec
Design within spec
Design within spec
Design within spec
Design within spec
Design within spec
Design within spec
Design within spec
Design within spec
Prototype cost: $390
1.5-2 mins
Sealants applied
Aluminum shield
Easily removal
Release valve on air compressor
Easily accesible
Sealants applied
Bolt and clamp used
Rechargeable battery
No custom components
Spot-welding, bending, cutting used
Results
Passed
Passed
Passed
Passed
Passed
Passed
Passed
Passed
Passed
Passed
Passed
Passed
P/F*
Passed
Passed
Passed
Passed
Passed
Passed
Passed
Passed
Passed
Passed
Passed
*Mass production will reduce costs of actual product.
Appendix E1
APPENDIX F - BUDGET
Budget Summary
Proposed Budget
Material and Components
Actual Budget
Cost
Material and Components
Hydraulic Motor
$150
Hydraulic Pump
$75
Air Compressor
$95
Control/Wiring
$25
Sheet Metal Shield
$25
Shield/Guard
$25
Hose
$5
Mounting Hardware
$30
Fittings
$6
Miscelaneous
$20
Rubber Sleeves
$15
Mounting Hardware
$10
Miscelaneous
$20
Total Cost
$325
Airbag
Cost
Total Cost
$170
$346
Appendix F1
APPENDIX G - DESIGN CALCULATIONS
Test Vehicle:
For the purpose of this project, the vehicle which this pneumatic jack was designed and
implemented is a Mitsubishi Eclipse as shown in Figure. This pneumatic jack was designed
based on the specifications of this vehicle. Some of the important specifications needed in the
design are shown below.
1998 Mitsubishi Eclipse GS
Curb Weight = 2842 lb
Wheelbase = 98.8 in.
Figure 12 – Test Vehicle
Center of Gravity/Jack Location Calculations:
Since one whole side of the vehicle will be lifted using a single jack, it is important to find the
location on each side at which the weight distribution will be equal between the front and rear
sections of the vehicle. The center of gravity of the vehicle along its length is the ideal location
of the pneumatic jack. If the pneumatic is not located at the center of gravity, both tires on one
side may not rise off the ground at the same distances. The center of gravity of an average
production car is 14 to 22 inches off the ground. The center of gravity in the vertical direction is
not important as the vertical location of the jack will be bound by the frame of the vehicle. The
average production car has 60/40 front to rear weight distribution between the two axles.
Assumptions:
Wheel base = 99 in
Weight Distribution = 60/40 front to rear.
Appendix G1
CG (Front to Back direction) = 99 * 0.4 = 39.6 inches back from the front axle.
Figure 13 – Center of Gravity Location
CG (Front to Rear Direction) = 40 inches
back of the front axle
Figure shows that the center of gravity along its length is located approximately 40 inches rear of
the front axle. The location of the jack along is width will be under the vehicles frame at the
edge of the vehicle, similar to the location where a standard vehicle jack is placed.
Design Load:
It is important to calculate the amount of load that the pneumatic will be lifting when in
operation on the test vehicle. The wheel-vehicle-airbag system work as a class 2 lever as shown
in Figure. The mechanical advantage of this lever system is used to calculate the input force
needed for a particular output force needed, which in this case is the 2000 lb design load. It is
assumed that the center of gravity of the vehicle is on or very close to the center line of the
vehicle along its length. Since the weight of the vehicle acts on its center of gravity and the input
force of the airbag is located at the edge of the vehicle, the input distance is approximately twice
that of the output distance. Figure shows the relation between the load, lift point and the fulcrum
about which the vehicle is raised.
Assumptions:
Vehicle Weight = 2842 lb
Additional Weight = 300 lb
Car Width = 68.5 in
Appendix G2
Analysis:
Vehicle-Tire-Airbag system work as a class 2 lever.
Mechanical Advantage of class 2 lever=
Input force = output force x output distance / input distance
= 3200 x 34.25 / 68.5 = 1600 lb
An additional 25% factor of safety in the design load.
Design Load = 2000 lb
Vehicle - Load
Pneumatic Jack - Force
Direction of Lift
Opposite Side Wheel - Fulcrum
Figure 14 – Wheel-Vehicle-Jack Lever System
The design load used throughout the design is 2000 lbs.
Shield Stress:
The shield is placed between the airbag upper plate and the vehicle frame. Figure shows the
location of shield case in relation to the airbag and vehicle frame. The shield undergoes bearing
load as it is compressed between the airbag upper bead plate and the vehicle frame. Figure
shows the projection of the bearing contact surface area of the vehicle frame on the shield case in
relation to the airbag upper plate.
Assumptions:
Design Load = F =2000 lb
Design Factor = N = 8 (repeated load)
Vehicle Frame Thickness = t = 1 inch
Appendix G3
Figure 15 – Projected Bearing Contact Area
Contact surface area = 6.23 * 1 = 6.23 in2
For Aluminum:
Stress bd = stress by / 2.48 = 1.6 * stress sy / 2.48 = 0.65 sy
Stress = f/a = 2000/6.23 = 321 psi
Design factor of 8 = stress = 321 * 8 = 2568 psi
Required Ultimate Strength:
Stress bd=stress by / 2.48
Stress by = 1.6 * stress sy
Stress bd= 1.6 * stress sy / 2.48
Sy = stress bd * 2.48 / 1.6 = 2568 * 2.48 / 1.6 = 3980.4 psi
Using Aluminum Sheet Metal:
Tensile yield strength of sheet metal (2014-0) = 10000 psi
Bearing Load = 2000 lb
Factor of Safety:
Factor of safety = 10000/3980.4 = 2.5
Figure 16 – Shield Stress FBD
Appendix G4
Lower Plate Stress:
The lower plate is attached to the bottom of the airbag to
give it a larger base. The plate exhibits compressive
stress.
Assumptions:
Load = 2000 lb
Design factor = 8
Bearing Load = 2000 lb
Plate Stress:
Plate surface area = 4 x 4 =16 in2
Stress = F/A = 2000/16 = 125 psi
Design factor of 8 = stress = 125 * 8 = 1000 psi
Tensile strength of sheet metal (2014-0) = 10000 psi
Figure 17 – Lower Plate Stress FB
Factor of Safety:
Factor of safety = 10000/1000 = 10
Angle of Airbag (Shear):
When the airbag is inflated, it expands in the vertical direction. The point at which the airbag
contacts the vehicle frame is fixed. As the airbag is released from the shield, it expands pushing
into the ground below. The load of the vehicle prevents the airbag from moving along the
ground. Since the wheel-vehicle-airbag system work as a lever, the air bag will not be at an
exactly 90 degree angle with the ground below. Variations in the level and height of the ground
below will further affect the angle of the airbag. This angle is calculated using basic geometric
principles assuming that only distance changing during the lifting process is that associated
directly with the airbag. The calculated angle is too small to exhibit any significant shearing
force. The airbag is designed to be used in such lever type applications and can withstand the
minimal shearing force.
Mounting Stresses:
There are two brackets holding the shield and airbag assembly to the bottom of the vehicle. The
weight of the airbag is 7.5 lbs and the weight of all the sheet metal used in the fabrication of the
shield and mounting brackets is approximately 3 lbs. The total weight of the assembly is no
more than 11 lbs. This is a very low load and the stress forces on the mounting brackets and
hardware are negligible.
Appendix G5
APPENDIX H – DETAIL DRAWINGS
Appendix H1
Appendix H2
Appendix H3
Appendix H4
Appendix H5
Appendix H6
Appendix H7
Appendix H8
APPENDIX I - PURCHASED COMPONENTS
Firestone Airstroke Actuator # 20
Aluminum 2014-0 20 Gauge Sheet Metal
Appendix I1
Campbell Hausfeld 12 VDC Portable Air Compressor:
Appendix I2
EDPM ¼ inch Air Hose, 25 ft:
3/8-16 Hex Bolt:
Appendix I3
Brass Hose Bard, ¼ inch Hose, 1/8 inch NPT Fitting:
J-B Weld Cold Weld Epoxy Solution:
Appendix I4
¼ inch Hose Clamps:
1 ¼ inch Hose Band Clamp:
Appendix I5
Pro-Seal 34 Waterproof Sealant:
Appendix I6
APPENDIX J - AIRBAG SELECTION GUIDE
Air Bag Types:
Appendix J1
Elastomer Selection:
Appendix J2
Firestone Airstroke Actuator Selection Guide:
Appendix J3
End Closure Selection Guide:
Appendix J4
Firestone Airstroke Actuator Style 20 Specification Sheet:
Appendix J5
APPENDIX K - BILL OF MATERIAL
Bill of Material
Material and Components
Airbag
Air Compressor
Sheet Metal Shield
Hose
Fittings
J-B Weld
Mounting Hardware
Hose Clamps
Sealant
Total Cost
Part Number
W01-358-6910
Campbell Hausfeld Portable
2014-0
EPDM 25 ft
(2) Elbow Brass Hose Barbs
One tube
Bolts - Washers - Spacers
(10) 1/4 inch
Pro-Seal 34
Cost
$170
$150
$25
$18
$6
$5
$5
$5
$6
$390
Appendix K1