Gearbox Project Creativity Journey

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Gearbox Project

Gearbox ProjectCreativity Journey

VERTICAL RACK & PINION LIFT

High stabilityHard to adjustMore suitable for smaller distancesGreater number of gearsSupports needed to keep rack in line

PULLEY SYSTEM

Reduces torque at rotating shaftIncreases length of string to liftFriction

SINGLE VS DOUBLE STRING SUPPORTSingle

Simple, compactHigh stress concentration in shaftOverlapping of string increases Torque required

Double

Less concentrated force in shaftOverlapping issueRequires more space

SCREW/WORM WINDING

Enables constant Torque

Difficult to manufacture

Planetary Gear SystemAdvantagesCompact and lightweightHigher efficiencyLess stress between teethLess distortionDisadvantagesDemands a higher degree of precisionMore complexPotentially difficult to make minor adjustments or replace parts after initial assembly

Sun gear: InputPlanetary Carrier: OutputRing gear: FixedThis puts the gearing system in reduction mode. Sun will rotate faster than the planetary carrierMaximum gear ratio is 10:1; this is unlikely to be enough for our applicationA two stage design could easily provide an adequate gear ratio However, complexity in assembly increases even more with two stages

Worm gearboxAdvantagesSimple 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.DisadvantagesExperience sliding friction.Create heat causes energy loses .Tooth wear increased.65%-80% efficiency.

Loadmotor

Improvement of worm gearboxGear 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.

Loadmotor

Compound Spur Gear TrainSimple to design and manufactureMore compact than a simple gear trainHigh efficiency for each stage More stages equals smaller gear sizing but at loss of efficiencyHigh stress in teeth

1:21:21:21:2

2-Stage vs 3-Stage vs 4-Stage (1:64)

2 X 1:83 X 1:44 X 1:2.26

Final DesignPlanetary seems to be the more effective solutionHowever, given limitations we are leaning towards a standard compounded gear train

Why?Much simpler design; assembly is an important factorThere will be issues that will need fixing/adjusting after the first cutEasier maintenance will allow us to address more issues quicker