Search results
Results from the WOW.Com Content Network
Gear train with an idler gear in the middle which does not affect the overall gear ratio but reverses the direction of rotation of the gear on the right. In a sequence of gears chained together, the ratio depends only on the number of teeth on the first and last gear.
A transmission (also called a gearbox) is a mechanical device which uses a gear set—two or more gears working together—to change the speed, direction of rotation, or torque multiplication/reduction in a machine. [1] [2] Transmissions can have a single fixed-gear ratio, multiple distinct gear ratios, or continuously variable ratios. Variable ...
Worm-and-gear sets are a simple and compact way to achieve a high torque, low speed gear ratio. For example, helical gears are normally limited to gear ratios of less than 10:1 while worm-and-gear sets vary from 10:1 to 500:1. [45] A disadvantage is the potential for considerable sliding action, leading to low efficiency. [46]
A relatively simple design of differential is used in rear-wheel drive vehicles, whereby a ring gear is driven by a pinion gear connected to the transmission. The functions of this design are to change the axis of rotation by 90 degrees (from the propshaft to the half-shafts) and provide a reduction in the gear ratio.
For instance, if the sun gear has 24 teeth, and each planet has 16 teeth, then the ratio is − + 24 / 16 , or − + 3 / 2 ; this means that one clockwise turn of the sun gear produces 1.5 counterclockwise turns of each of the planet gear(s) about its axis. Rotation of the planet gears can in turn drive the ring gear (not depicted ...
A face gear set typically consists of a disk-shaped gear, grooved on at least one face, in combination with a spur, helical, or conical pinion. A face gear has a planar pitch surface and a planar root surface, both of which are perpendicular to the axis of rotation. [1]
An idler gear is a gear wheel that is inserted between two or more other gear wheels. The purpose of an idler gear can be two-fold. Firstly, the idler gear will change the direction of rotation of the output shaft. Secondly, an idler gear can assist to reduce the size of the input/output gears whilst maintaining the spacing of the shafts.
Therefore, regardless of the worm's size (sensible engineering limits notwithstanding), the gear ratio is the "size of the worm wheel - to - 1". Given a single-start worm, a 20-tooth worm wheel reduces the speed by the ratio of 20:1. With spur gears, a gear of 12 teeth must match with a 240-tooth gear to achieve the same 20:1 ratio.