Below is a list of Helical Gears manufacturers from Chicago, Illinois. Helical gears are circular in shape with teeth that have been cut in a helical path at an angle relative to the gear’s axis of rotation. Helical gears can also be aligned parallel or crossed, allowing gears to transmit torque perpendicularly. This is possible because the rotation angle of the teeth can be adjusted by 90°. However, a parallel orientation is the most common. Helical gears are often called spiral gears when mounted on shafts at right angles.