Speed reducers, also known as gear reducers, are mechanical devices that perform for two major functions. The devices are used to multiply the amount of torque produced by an input source to increase the amount of usable work. Gear reducers are also used to reduce the speed of the input power source to get the best possible output speeds. There are four major kinds of speed reducers: planetary, bevel, gear train, and worm gear reducers
. Gear reducers with right-angled designs are often made with bevel or worm gearing, but there are hybrid drives in the market. The helical bevel gear reducer features slanted teeth that are more powerful than spur gears and emit less noise. This is because they have higher meshing ratios as compared to spur gears
. Helical gear reducers are mainly used for power transmission.