In a continuing pursuit to develop and introduce better technology to media milling, Hockmeyer Equipment has received notice that its fifth patent covering immersion mill enhancement has been granted by the U.S. government. Patent Number 7,559,493 covers the deterrence of wear at a bearing construct in a basket media mill.
The device involves the introduction of slots in the rotating peg hub within the basket. As the hub rotates, centrifugal force pulls the media and feedstock away from the polymer-bearing construct within the peg hub. This results in two favorable conditions: Extended bearing life regardless of the media type or size and elimination of micro media escaping through the clearance between the rotating drive shaft and the bearing construct.
Bearing life (typically six months to 1-1/2 years) has been more than doubled.
Micro media (typically smaller than .3mm) is no longer a containment problem. The centrifugal hub prevents micro media from escaping thru the polymer-bearing construct and the auger in the upper feed tube into the mill prevents media from floating out as the mill is immersed into the feedstock.
The addition of this feature to the existing Hockmeyer mill patents enhances their utility by allowing the use of micro media to disperse particles into the low nanometer range (120 nanometers and below) in a fraction of the time required for conventional horizontal milling technology.