US Patent 7566164 Floating agitation device to heat and froth milk

The present invention provides an agitation device, comprising a motor for supplying rotational power, an outer shaft operatively connected to the motor, an extendible inner shaft positioned within the outer shaft and operatively connected thereto, an agitator positioned on the extendible inner shaft, and a floatation device positioned on the extendible inner shaft distal to the agitator from the motor for providing a buoyant force to the extendible inner shaft and the agitator for immersing the agitator at a predetermined level in a liquid. The present invention also provides a device for agitating and heating a liquid.