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 The robot gearbox contains a worm drive mechanism. This consists of a worm gear fixed to the motor and a pinion gear fixed to the axle. It takes several complete turns of the motor to give one complete turn of the axle. It is therefore a good mechanism for reducing speed. The mechanism also converts a small turning force into a larger turning force.
Find out how the size of the pinion gear affects the turning speed and turning force in a worm drive mechanism.
| Small pinion gear | Large pinion gear | | Small weight | weight is lifted quickly | weight is lifted slowly | | Large weight | weight starts to lift but keeps slipping back. Motor starts to get hot and glows red. | weight is lifted slowly (at the same speed as the small weight). |
Now you have completed Lesson 4
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