SPEED FLEX GENERATOR

The circular spline is a rigid circular ring with teeth on its inside. The ball bearing lets the flex spline rotate independently to the wave generator's shaft.

SPEED FLEX GENERATOR

The flex spline fits tightly over the wave generator, so that when the wave generator plug is rotated, the flex spline deforms to the shape of a rotating ellipse and does not slip over the outer elliptical ring of the ball bearing. Teeth are positioned radially around the outside of the flex spline. This results in significant flexibility of the walls at the open end due to the thin wall, and in the closed side being rigid enough to be tightly secured (to a shaft, for example). The sides of the spline are very thin, but the bottom is relatively rigid. The flex spline is shaped like a shallow cup. The elliptical plug is inserted into the bearing, forcing the bearing to conform to the elliptical shape but still allowing rotation of the plug within the outer bearing. The wave generator is made of two separate parts: an elliptical disk called a wave generator plug and an outer ball bearing. More complex versions have a fourth component normally used to shorten the overall length or to increase the gear reduction within a smaller diameter, but still follow the same basic principles. The mechanism has three basic components: a wave generator (2 / green), a flex spline (3 / red), and a circular spline (4 / blue). The strain wave gearing uses the elasticity of metal. It can provide gear reduction but may also be used to increase rotational speed, or for differential gearing. Strain wave gearing is commonly used in robotics and aerospace. High gear reduction ratios are possible in a small volume (a ratio from 30:1 up to 320:1 is possible in the same space in which planetary gears typically only produce a 10:1 ratio).ĭisadvantages include a tendency for 'wind-up' (a torsional spring rate) in the low torque region. good resolution and excellent repeatability (linear representation) when repositioning inertial loads,.reconfigurable ratios within a standard housing,.Strain wave gearing has some advantages over traditional gearing systems such as helical or planetary gears, including: The German company Harmonic Drive SE manufactured the first series-produced gears under the product name or registered trademark Harmonic Drive. Strain wave gearing (also known as harmonic gearing) is a type of mechanical gear system that uses a flexible spline with external teeth, which is deformed by a rotating elliptical plug to engage with the internal gear teeth of an outer spline.

Harmonic Drive SE strain wave gear set consisting of wave generator bearing (top left), flexspline cup (top right) and circular spline ring (bottom).

Speed flex