The Three Common Winch Gearing Systems
The worm gear, planetary gear, and spur gear are the three most common winch gearing systems. Regardless of the winch gearing system chosen, the function of the winch gearing system is to convert a motor to a lower speed, higher torque winch drum. The more the revolutions of output are reduced by the gearing system, the higher the efficiency of the motor. In other words, the winch motor will not have to work as hard to accomplish a given task with a higher winch gearing system reduction ratio.
The worm gear achieves efficiencies in the neighborhood of 40%. The worm gear works on a winch with a clutch mechanism to control free spooling. As such, the winch is able to self-brake. The self-braking system adds reliability to the winch. While the worm gear offers a great gearing system reduction ratio, this does result in decreased winching speeds.
In contrast, the planetary gear system achieves an efficiency of about 65%. The spur gear system achieves an efficiency of 75%. That leads both of these gear systems to be susceptible to free spooling unless a braking system is installed. The planetary gear system is found more commonly than the spur gear system because it runs very smoothly and has a lot of strength. The spur gear system is only currently found on the popular WARN M8274 winch system.