A gear is a toothed wheel having a special tooth shape or profile enabling it to mesh smoothly with other gears.These are used to transmit power from one shaft to another shaft in closed contact. These gears are classified according to location of the shaft, position of the tooth and types of tooth shapes. The follow gears are mainly used
- Straight Gear [spur gear]
- Helical gear
- Bevel gear
- Worm gear
- Rack and Pinion
These are also called as spur gears the gears having tooth in straight & parallel to the axis of the shaft. These gears are used to transmit the power in gearbox of automobiles. This type of gears are used to transmit more power.
In these helical gears the gears having the tooth with some angles with respect to the axis of shaft. This angle doesn’t meet more than 30-50°. If the angle is increased the gear can’t transmit the power effectively and it effects the life of the gear.
Bevel gears are used to transmit the power from one direction to another direction. For example the power developed by one shaft is in X-axis & the power need to be transmit to 90° i.e., to Y-axis. Then these gears are used. In these the gears having some slant & angled position.
In these the position of shaft are non parallel to each other. In this type of gears a worm & a wheel worm having a circular spiral gear like a spring in spiral binding. The wheel may have the tooth angles or straight form. Then the power input is given to worm then the output may obtained at wheel according to our requirement
Rack and Pinion :-
In this type of gear having a infinitely large diameter the tooth are laid flat.Torque can be converted to linear force by meshing a rack with a pinion: the pinion turns; the rack moves in a straight line.
Even a gear can be manufactured by using a gear in machine