gear

A gear or cogwheel is a rotating machine part having cut teeth or, in the case of a cogwheel, inserted teeth (called cogs), which mesh with another toothed part to transmit torque. Geared devices can change the speed, torque, and direction of a power source. Gears almost always produce a change in torque, creating a mechanical advantage, through their gear ratio, and thus may be considered a simple machine. The teeth on the two meshing gears all have the same shape. Two or more meshing gears, working in a sequence, are called a gear train or a transmission. A gear can mesh with a linear toothed part, called a rack, producing translation instead of rotation.
The gears in a transmission are analogous to the wheels in a crossed, belt pulley system. An advantage of gears is that the teeth of a gear prevent slippage.
When two gears mesh, if one gear is bigger than the other, a mechanical advantage is produced, with the rotational speeds, and the torques, of the two gears differing in proportion to their diameters.
In transmissions with multiple gear ratios—such as bicycles, motorcycles, and cars—the term "gear" as in "first gear" refers to a gear ratio rather than an actual physical gear. The term describes similar devices, even when the gear ratio is continuous rather than discrete, or when the device does not actually contain gears, as in a continuously variable transmission.

View More On Wikipedia.org

    Recent Content Tagged With gear

  1. klipdrifter
  2. Matt_FV
  3. Philip Dunkley
  4. Steph
  5. Dave
  6. Abdul muhaimin
  7. MrDeedz
  8. Hanre "Trol" Slier
  9. Ruwaid
  10. Nicholas Jones
  11. Jarred1978
  12. Paul33
  13. Safz_b
  14. Hersh13
  15. Leven Naicker
  16. Mr. B
  17. Zah007
  18. Larry
  19. Steve Claassen
  20. Paul33