Gearing Definition and 27 Threads

An epicyclic gear train (also known as a planetary gearset) consists of two gears mounted so that the center of one gear revolves around the center of the other. A carrier connects the centers of the two gears and rotates to carry one gear, called the planet gear or planet pinion, around the other, called the sun gear or sun wheel. The planet and sun gears mesh so that their pitch circles roll without slip. A point on the pitch circle of the planet gear traces an epicycloid curve. In this simplified case, the sun gear is fixed and the planetary gear(s) roll around the sun gear.
An epicyclic gear train can be assembled so the planet gear rolls on the inside of the pitch circle of a fixed, outer gear ring, or ring gear, sometimes called an annular gear. In this case, the curve traced by a point on the pitch circle of the planet is a hypocycloid.
The combination of epicycle gear trains with a planet engaging both a sun gear and a ring gear is called a planetary gear train. In this case, the ring gear is usually fixed and the sun gear is driven.

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  1. L

    Gears create more torque? Prove it

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  2. D

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  3. S

    Gearing Backlash Arcsine to Arc minutes

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  4. SquidPhysics

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  5. person123

    Magnetic Gears For Power Transmission

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  6. Eddie714

    I in designing a single speed reduction gearbox

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  7. drwly

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  8. T

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  9. thorq

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  10. K

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  11. A

    Designing a Gearing System for an Analog Clock: Need Help!

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  12. A

    Zero backlash worm gearing for pan and tilt

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  13. C

    Can Epicyclic Gearing Operate with No Fixed Axis?

    Homework Statement The teacher said it is possible to use an epicyclic gearing with no axis fixed but nobody use the gearing like that. I watched this video: at time 42s it's possible to watch it. I have 2 questions: 1) Is it possible to used the epicycloidal train with no axis fixed ? 2)...
  14. D

    Tower Clock Gearing and Motor Speed

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  15. L

    How does bicycle gearing affect mechanical advantage?

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  16. B

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  17. Y

    RE: vehicle weight, HP, and gearing comparison between vehicles

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  18. L

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  19. 0

    Firt time postjust a quick question about magnetic gearing

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  20. K

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  21. S

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  22. K

    Is a Toroidal Engine a More Powerful Alternative to Reciprocating Engines?

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  23. L

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  24. A

    Gearing Mechanics: Torque/HP & Gear Ratio Explained

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  25. zoobyshoe

    Gearing Up For Projects That Fizzle

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  26. W

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  27. J

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