A gear train is a mechanical system formed by mounting gears on a frame so that the teeth of the gears mesh together and engage. The teeth are used to help the gears roll on each other without slipping. The energy from one gear is transfered to the next gear through the rotation between the contacting toothed wheels.
Gears are generally used for one of four different reasons: 1. To reverse the direciton of rotation: notice in the animated image (figure 1) to the right that when two gears mesh, their directions are opposite of one another 2. To increase or decrease the speed of rotation: notice in the aniimated image (figure 1) to the right that the smaller gear is spinning faster than the larger gear 3. To move rotation motion to a different axis: notice in the image (figure 2) to the right how the center of the gear is on the x or the y axis. 4. To keep the rotation of two axes synchronized The number of teeth on a gear is used to calculate the gear ratios found within the mechansims. Use this slide show to help you understand the different types of gears and how to calculate the gear ratios. |
Figure 1.
Figure 2. |