Cone Drive Harmonic Solutions, also known as strain wave gearing, is a compact, torque dense type of gear. Other advantages are high positional accuracy, high torsional stiffness, and zero backlash. The Circular Spline, Flexspline and Wave Generator work together to make up the strain wave gear. There are two fewer teeth on the Flexspline relative to the Circular Spline which means that every wave generator rotation results in a slower rotation of the Flexspline than the Circular Spline.
The Wave Generator is comprised of two parts, an elliptical disc and an outer ball bearing.
The Wave Generator is comprised of a specially designed thin raced ball bearing that is fitted onto an elliptical hub, a drive shaft connects to the hub of the wave generator, and the ball bearing transmits torque to the gear mesh.
The Flexspline is composed of thin alloy steel for increased compliance in radial deflection.
The Wave Generator is pressed into the Flexspline. This deforms the Flexspline to the shape of the Wave Generator ellipse and allows tooth engagement with the Circular Spline.
The Circular Spline is a rigid circular ring with gear teeth on the inner diameter.
When the gearing is assembled the teeth of the Flexspline engage across the major axis of the Wave Generator ellipse. With the assembly complete, rotation of the Wave Generator hub creates gear reduction between the Flexspline and Circular Spline.