Gears are fundamental mechanical components used to transmit motion and force between machine parts. Their primary function is to change the , , and direction of a power source. Understanding gears and gear ratios is essential for anyone involved in mechanical design, engineering, or physics. Used for parallel shafts, spur gears are simple and efficient but can be at high speeds. They can reverse the of rotation or change the force or speed of rotation, especially when using different size gears.
Bevel gears are conical gears used to transmit motion between intersecting shafts, often at a angle. They are used to change the angle of rotation. Helical gears have angled teeth, offering smoother and quieter operation, making them suitable for applications. A worm gear is a type of gear that consists of a screw-like gear called a worm that meshes with a toothed gear called a worm wheel. It is commonly used in applications where a high gear ratio is , such as elevators and conveyor systems.
The gear ratio is the relationship between the number of on two meshing gears. It determines how the rotational speed and torque are modified between the driving gear (input) and the driven gear (output). Gear ratio can be expressed as Output Teeth : Input Teeth, for example, if a driving gear with 10 teeth meshes with a driven gear with 20 teeth, the gear ratio is . This means the driven gear rotates once for every two rotations of the driving gear, resulting in the torque being doubled but the being halved.