Rotary mill for micronic grinding

Claim 1

A rotary mill comprising a container having an open end; a tubular piece having an end bellmouthed, which bellmouthed end is coupled to the open end of the container; air inlet means coupled to the bellmouthed end of the tubular piece; a hopper coupled to the air inlet means for feeding material into the tubular piece, said hopper including a regulating feed valve; a revolving disc located in that end of the tubular piece opposite to its bellmouthed end; a funnel shaped deflecting piece located around said tubular piece and having one end registering with the revolving disc for feeding semi-ground material thereto; wall means surrounding the revolving disc and the deflecting piece and having one end projected and bent towards the deflecting piece, against which wall means the materials flung from the revolving disc will strike; a circular plate registering with the revolving disc and joined to the wall means, so that material flung from the revolving disc forms a bank in the region of the joint and which circular plate together with the wall means form a first receiving chamber for material not yet fully ground; a first passage defined by the bent projection and the deflecting piece for the semi-ground material be returned to the revolving disc; a second passage defined by the bent projection and the bellmouthed end of the tubular piece for passing the finely-ground material; a second receiving chamber defined by the wall means and the container to house the finely-ground material from the second passage; and outlet means for the finely-ground material obtained from the second receiving chamber.