Patent ID: 7152522

Claim:
A screw press for compressing a combination of solid and liquid matter, the screw press comprising: a longitudinally extending shaft having a proximal end and a distal end; screw threads concentrically positioned around and affixed around said shaft and extending a substantial portion along the length of said shaft, the rotation of said shaft and threads conveying material from the proximal end of said shaft to the distal end of said shaft; a motor for rotating said shaft and a screw threads; a housing for encasing a substantial portion of said shaft and screw threads, said housing including an inlet located for the introduction of material to said screw threads and an outlet for the discharge of liquids, said outlet being a strainer means positioned at said distal end of said shaft, the rotation of said screw threads causing material to be conveyed from the proximal end of said shaft to the distal end of said shaft to compress material against said strainer means to discharge fluids through said screen; and a rotatable radial gate valve including a body, a plurality of teeth, and an axis of rotation about which said radial gate valve rotates, said body and said teeth further defines the rotatable gate valve's plane of rotation within which said rotatable gate valve rotates, said rotatable gate valve positioned with one or more of said plurality of teeth positioned between said screw threads to inhibit a back flow of material through said screw threads when said shaft and said screw threads are rotated, said radial gate valve also being positioned with its plane of rotation angled relative to a longitudinal axis of said shaft so that said axis of rotation is not perpendicular to said longitudinal axis of said shaft, wherein said plane of rotation of said radial gate valve is substantially perpendicular to said screw threads and said axis of rotation substantially parallel to said screw threads.