The document discusses various gearbox design options for lifting equipment, including their advantages and disadvantages. It considers rack and pinion lifts, pulley systems, single vs. double string supports, screw/worm winding, planetary gear systems, worm gearboxes, and compound spur gear trains. It ultimately recommends a standard compounded gear train design due to its simpler assembly and maintenance compared to other options like planetary gears, which would be preferable but have greater complexity.

1. Gearbox Project
Creativity Journey

2. VERTICAL RACK & PINION LIFT
- High stability
- Hard to adjust
- More suitable for smaller distances
- Greater number of gears
- Supports needed to keep rack in line

3. PULLEY SYSTEM
- Reduces torque at rotating
shaft
- Increases length of string
to lift
- Friction

4. SINGLE VS DOUBLE STRING
SUPPORT
Single
- Simple, compact
- High stress concentration in shaft
- Overlapping of string increases Torque
required
Double
- Less concentrated force in shaft
- Overlapping issue
- Requires more space

5. SCREW/WORM WINDING
- Enables constant Torque
- Difficult to manufacture

6. Planetary Gear System
• Advantages
• Compact and lightweight
• Higher efficiency
• Less stress between teeth
• Less distortion
• Disadvantages
• Demands a higher degree of precision
• More complex
• Potentially difficult to make minor adjustments or replace parts after initial
assembly

7. • Sun gear: Input
Planetary Carrier: Output
Ring gear: Fixed
• This puts the gearing system in reduction mode. Sun will rotate faster than the planetary
carrier
• Maximum gear ratio is 10:1; this is unlikely to be enough for our application
• A two stage design could easily provide an
adequate gear ratio
• However, complexity in assembly increases
even more with two stages

8. Worm gearbox
Advantages
• Simple way to achieve a
high torque.(Gear ratio from 10:1 to 500:1)
• Quiet and relatively smooth while
running in only one direction.
• Small size less spaced required.
Disadvantages
• Experience sliding friction.
• Create heat causes energy loses .
• Tooth wear increased.
• 65%-80% efficiency.
Load
motor

9. Improvement of worm
gearbox
• Gear may or may not drive worm.
• If the lead angle is small, the gear's teeth may simply
lock against the worm's teeth.
• The force component circumferential to the worm is
not sufficient to overcome friction.
Load
motor

10. Compound Spur Gear Train
• Simple to design and
manufacture
• More compact than a simple
gear train
• High efficiency for each
stage
• More stages equals smaller
gear sizing but at loss of
efficiency
• High stress in teeth
1:2
1:2
1:21:2

11. 2-Stage vs 3-Stage vs 4-Stage (1:64)
2 X 1:8 3 X 1:4 4 X 1:2.26

12. Final Design
• Planetary seems to be the more effective solution
• However, given limitations we are leaning towards a standard
compounded gear train
• Why?
• Much simpler design; assembly is an important factor
• There will be issues that will need fixing/adjusting after the first cut
• Easier maintenance will allow us to address more issues quicker