A worm shaft is a type of gear with a raised ridge that provides a surface for ball bearings and is commonly found in steering boxes and electric motors. It reduces speed and increases power, and is used in power tools and fishing reels. Heavy oil is the best lubricant for worm shafts.
A worm shaft, or worm gear as it is often known, is a type of long spur gear that provides a surface on which ball bearings can be mounted. Resembling the stripes on a candy cane, this shaft has a raised ridge that wraps around the shaft and runs from top to bottom. This type of equipment is most often found within the inner workings of a steering box in a car.
When used in an electric motor application, the worm shaft is commonly used to slow down a driven gear. As the teeth of a gear mesh with the gear on the worm shaft, the gear rotates one gear tooth for every full turn of the worm gear. The driving speed is reduced by the number of teeth on the driven gear. For example, a five tooth gear would slow down by a fifth and a 10 tooth gear would slow down by a tenth.
Unlike a conventional gear set, the worm shaft cannot be reversed to increase the speed of a driven gear. Such assemblies can be found on many power tools and devices, such as electric drill motors and circular saws. They can also be found in sports equipment such as fishing reels. Many fishing reels use a worm shaft to operate the line level wind on a bait reel, as well as to operate the line winder on a spinning reel or spinning casting reel.
By using the worm shaft on a fishing reel, the operator can spin the handle of the reel at a comfortable speed while the worm gear reduces its action to a manageable speed. This reduction in speed also increases the amount of power the reel has to fight a big fish. The mechanical advantage of this type of simple machine allows the use of small fishing reels to chase larger fish.
While it is typical custom to use grease to lubricate gears, the worm shaft operates at peak performance levels with a very heavy oil used as a lubricant. The fluidity of heavy oil allows the gears to roll smoothly against each other, while grease tends to get sticky and cause erratic motion. In some machines, the mixture of heavy oil and light grease is combined to lubricate the gears. In any configuration, a clean and well-maintained worm gear will produce the best results.
Protect your devices with Threat Protection by NordVPN
