Patent ID: 7997659

Claim:
A rotary cutter comprising: a hub with a cutter ring integrally formed with or mounted to the hub, the cutter ring circumferentially surrounding the hub and centrally positioned between a first end and an opposite second end of the hub, the hub having a longitudinal, through first bore formed therein which extends between the first end and the second end; a shaft positioned inside the first bore, the shaft extending from each end of the bore whereby the shaft may be supported at both ends by a mounting arrangement on a cutter head, the shaft having a large diameter bearing surface and a small diameter portion, wherein the large diameter bearing surface and the small diameter portion are connected by a transition radius area; a sleeve bearing positioned in the first bore between the shaft and the hub; and at least one seal group positioned between at least one of the small diameter portion and the hub and the transition radius area and the hub.