Helical Gear Speed Reducers
Provide high-efficiency speed decrease through 1, 2, 3, or 4 sets of gears. Power is transmitted from a high-swiftness pinion to a slower-speed gear. Helical gears usually operate with their shafts parallel to one another. The two most common types are the concentric (insight and result shafts are in collection) and parallel shaft (insight and output shafts are offset). Single-stage helical gear reducers are usually used for equipment ratios up to about 8:1. Where lower speeds and higher ratios are needed, dual, triple, and quadruple equipment reduction stages may be used.
Worm Gear Speed Reducers
A single reduction rate reducer can achieve up to 100:1 reduction ratio in a small package. Referred to as right angle drives, these contain a cylindrical worm with screw right angle worm gearbox threads and a worm. With a single begin worm, the worm equipment advances only 1 tooth for each 360-degree change of the worm. So, whatever the worm’s size, the apparatus ratio is the ‘size of the worm equipment to 1′. Higher reduction ratios can be created by using double and triple reduction ratios.
Basic Types of Gearboxes
The purpose of a gearbox is to increase or reduce speed. Because of this, torque output will be the inverse of the function. If the enclosed drive is definitely a swiftness reducer, the torque result will increase; if the drive boosts speed, the torque output will decrease. Gear drive selection elements include: shaft orientation, swiftness ratio, design type, nature of load, gear ranking, environment, mounting position, working temperature 
range, and lubrication.