Gears are the key components of many motors and machines. The gear can increase torque output by providing gear reduction and adjust the direction of rotation of the shaft, such as the rear wheel of a car. Here are some basic types of gears, and how they differ from each other.

 

Spur gear

The most common gear is a spur gear, used for gear reduction. The teeth on the spur gear are straight and mounted in parallel on different axes. Spur gears are used in washing machines, screwdrivers, clockwork, and other devices. Because of gear meshing and collision, each impact produces huge noise and vibration, which is why the use of spur gears in automobiles and other machinery is not. A normal gear ratio range is 1: 1 to 6: 1.

 

Spiral gears

Due to tooth interaction, helical and spur gears work more smoothly and quietly. Bevel gear teeth and the gear surface at an angle to cut. When two teeth start to engage, the contact is gradual - starting from one end of the tooth and maintaining contact as the gear rotates to full engagement. A typical range of helix angle is about 15-30 degrees. Thrust load changes directly with the size of the tangent of the helix angle. Spirals are the most commonly used gears in transmissions. They also produce a great deal of thrust and use bearings to help support thrust loads. Helical gears can be used to adjust the angle of rotation by 90 degrees. When mounted on a vertical axis. Its normal gear ratio range is 3: 2 to 10: 1.

 

Bevel gear

Bevel gear is used to change the direction of rotation of the shaft. Bevel gear with straight teeth, spiral or hypoid tooth shape. Spur and spur gear have similar characteristics, also have a great effect when engaged. Similar to spur gears, spur bevel gears have a normal gear ratio in the range of 3: 2 to 5: 1.

 

Helical teeth operate the same way as helical gears. They produce less vibration and noise than straight teeth. The right side of the helical bevel is the outer half of the tooth, running obliquely clockwise from the plane of the shaft. Helix angle left hand counterclockwise. The normal gear ratio range is 3: 2 to 4: 1.

 

The hypoid gear is a helical gear whose shape is a hyperboloid of revolution rather than a conical shape. The hypoid gear places the pinion on the ring gear or crown wheel. This allows the pinion to be larger in diameter and provide more contact area.

 

The pinion and the gear are usually always the opposite, and the pinion's helix angle is usually larger than the gear's angle. Hypoid gears are used in powertrain systems because of their large gear ratios. Normal gear ratio range is 10: 1 to 200: 1.

 

Worm gear

Worm gear for large gear reduction. Transmission ratio range from 5: 1 to 300: 1 is typical. The purpose of setting is to allow the worm to rotate the gear, but the gear can not turn the worm. The worm angle is shallow, so the gear is held in place due to the friction between the two. The transmission is suitable for conveyor systems where the locking function can be used as a brake or an emergency stop.