US Patent 6857191 Rotary knife having vacuum attachment

A rotary knife having a ring blade that defines a closed loop cutting surface for cutting material which the ring blade contacts during rotation. Materials cut using the blade such as meat cut from a carcass or trimmed from a piece of meat are suctioned away from the blade. The material is drawn into a blade housing which supports the ring blade. A housing body has a wall that defines a housing interior into which material separated by the cutting surface of the ring blade moves as it is cut. The blade housing body defines a bearing surface that is defined by a wall of the housing body that supports the ring blade and allows the ring blade to rotate with respect to the blade housing. Alternate coupling designed of the housing body allow the blade housing to be coupled to a suction tube for withdrawing meat from the interior of the blade housing.