Transcript MCEG-3043-Machine Design I Open

PACE Collaborative Project: Emerging
Market Vehicle
Transmission Design
Team member:
Anthony Smith
Kevin Scott
Decorian Harris
Jacque Thornton
Advisor: Dr. Xiaobo Peng
Department of Mechanical Engineering
Prairie View A&M University, Prairie View, Texas
Outline
Project Goal and Objectives
 Project Planning
 Detailed System Design
 Results
 Conclusion and Recommendations
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Goals and Objectives
GOAL: To develop an efficient transmission/gearbox
design to suit the needs of the emerging market vehicle.
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Suitable for an
emerging market
Inexpensive to produce
High fatigue safety
factor
High strength capacity
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Ability to handle high
torque and horsepower
Lightweight
Allowance for ample
clearance
Should operate under
extreme conditions
Constraints on Transmission
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Length: 300 mm maximum
Width: 350 mm maximum
Height: 300 mm maximum
Weight according to total weight of vehicle.
Project Management: Gantt Chart
Gear Train: Calculation Equations
Minimum Number of Teeth
N pa =
2 · k
2
( 1 + 2 · m ) · sin ( )
Gear Diameter
da =
Na
· (m + (m
wb =
p2
N pa
N pb
Ta =
wa
· 550 · 0.5 · 60
· wa
=
Safety Factor
n cawear
=
S ca · Z N
cawear
Velocity
Vabin
0.5
2
+ ( 1 + 2 · m ) · sin ( ) )
Number of Revolution
Torque
H
2
· da · wa
12
Transmitted Load
Wt abin
=
33000 ·
H
Vabin
)
Design Calculations
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Using a creditable machine design textbook, calculation for tooth
number, safety factors, bending, wear, and stress were done.
Tooth Number
Tooth Number Diameter of Revolution of
Safety
Minimum [Teeth] Used [Teeth]
Gear [ in] Gears [Rev / min] Factors Gear Ratio Used
Gear 2
14
28
4
3000
1.713
21
42
6
2000
1.421
14
31
4.429
3000
1.817
17
39
5.571
2385
1.634
13
32
4.571
3000
1.85
15
38
5.429
2526
1.707
15
15
2.143
3000
1.134
29
30
4.286
1500
0.8921
Gear 10
13
35
5
3000
1.942
Gears for 4th
Gear 11
Gear
12
35
5
3000
1.942
Gear 3
Gears for 1st
Gear
Gear 4
Gear 5
Gears for 2nd
Gear
Gear 6
Gear 7
Gears for 3rd
Gear
Gear 8
Gear 9
Gears for
Reverse
1.5
1.258
1.88
2.067
7
1
Gear Design & FEA Analysis
Shaft Design
Input shaft
Reverse shaft
Output shaft
Housing
Upper housing
Bottom housing
Other Major Components
Synchronizer
Slider for synchronizer
Reverse engager shaft
Synchronizer engager
Other Major Components
Bearing gasket
Bearing
Engager shaft
Transmission Assembly
Transmission Assembly
Results
Design is created to fit constraints.
 Design was verified by FEA.
 It is a safe transmission design.
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Conclusion & Recommendations
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Developed a successful design
Better communication between Universities
involved
Obtaining up to date software