When most people think about gears, they conjure images of what’s known as “spur gears,” the simplest type of gear. These gears have a conventional “gear” shape, consisting of a disk with individual teeth that extend out from the center in straight lines. While functional and appropriate for many contexts, these gears occupy only a small niche in the world of gear manufacturing. In most cases, there’s a better gear for the job, including helical gears—one of the most common and important types of gear in existence.
Helical Gears in a Nutshell
Helical gears are similar to traditional spur gears, but with an extra refinement; rather than having the teeth edge parallel to the axis of rotation, as in a traditional gear, they’re set at an angle (which is variable depending on the function of the gear). Essentially, they look like spur gears, but with teeth that are slanted one way or the other.
Helical gears have a major advantage when operating in parallel to one another; because the angle teeth engage gradually rather than suddenly, the movements of the gears are smoother and quieter. When noise abatement is a priority, or when speeds are abnormally high, helical gears are almost always a better choice. However, there is one critical disadvantage; there’s a degree of thrust along the gear’s axis, which requires the addition of thrust bearings and some special considerations with lubricant.
Skew Gears
Helical gears don’t just have to be placed in parallel with one another. They can also be set at an angle in a setup known as skew gears; this allows motion to transfer from one direction to a perpendicular direction in a given arrangement.
Double Helical Gears
There’s also a variant of the helical gear known as the double helical gear, which has a groove down the middle to split the angle of teeth in two different directions, usually in a V shape. From the side, they look like two helical gears stuck together. They’re more difficult to manufacture than traditional helical gears, but also reduce the need for thrust bearings.
Helical gears are one of the most important sub-types of gear we manufacture. If you’re interested in getting a quote or learning more, be sure to contact us!