MACHINE DESIGNGearbox design (Creative Journal)GROUP MEMBERS: SEAN MORRIS (LEADER) - 100596648

HAROLD CHIANG - 101009561 CHAI BOON XIAN - 100989358 NIGEL FENG - 100583682

IntroductionGearbox – lifting a 10kg weight up a ramp for at least 500mm distance

Method Used – 4-3-5 Method (Creativity Tool)

Idea Generation Method: 4-3-5

Originally from 6-3-5 method, but we modify it slightly as our group only consists of 4 members.

Total of 12 ideas were generated by all 4 of us. After reviewing all concepts generated, we have selected 6

designs that are feasible and distinctively different from others.

1st Gearbox Design Pros:

I. Multiple gears to distribute the loadII. Good torque to pull the loadIII. Big spool/shaft so that more thread can be

rolled in per revolutionIV. Only one gear train used, so power lost via

friction is minimized Cons:

I. Only one gear train, the force might be too much for the gears

II. With small gear driving big pinion, the gearbox will have good torque but the speed will be slower.

2nd Gearbox Design PROS:

I. Simple & easy design.II. Double pulley design could lift heavier

weight.III. More torque through reduction ratio in the

gearing. CONS:

I. May have insufficient gears to lift the weight.

II. Possibly too much stress on the gearsIII. Pulleys could wind at different rates, when

using two strings.

Pros:I. More gears to distribute stressII. Double pulley system provides more

support when pulling the 10kg loadIII. Provides more torque (reduction ratio)IV. Less stress on gears

Cons:I. The two bigger gears could mesh and not

turn properlyII. Shafts could rotate at different rates

depending on gear configurations

3rd Gearbox Design

ProsI. Smaller breathII. Dual winding design to split the tension

on each stringIII. Simple gear train systemIV. Greater torque

ConsI. More stress acted upon the driving gearII. Stall may occur

4th Gearbox Design

Pros:I. Force distributed throughout gears and shaftII. Less stress on gearsIII. More torque (reduction ratio)

Cons:I. Single pulley might not be able to handle

10kg weightII. Meshing possibility III. Connecting motor to shaft might interfere

with driven pinion

5th Gearbox Design

6th Gearbox Design Pros:

I. More gears to distribute stress II. Balanced and faster winding speedIII. Better control with pulley in the middle

Cons:I. Wider breathII. More gears equal to more friction

producedIII. May have insufficient torque to pull the

load

Finalization of Concepts

After thorough review and consideration, we have finally decided to go with ideas 1, 2 and 3.

Further analysis will be done to select which design to be sent for fabrication.

Potential Gearbox Design

2nd Design1st Design 3rd Design

Conclusion

We have took in account of all factors such as friction, gear stress, speed, torque and many more into this project.

We have utilized creativity tool: 4-3-5 Method well to come out with designs and selecting the best among them.