Dredge cutterhead

摘要

A dredge cutterhead has a plurality of helical arms inter-connecting a hub and a ring. Each of the arms has a front leading edge for attachment of cutting teeth. In one aspect, each of the arms has a trough portion, and the arm is shaped such that dredged material is directed toward the ring along the center of the trough portion. In another aspect, the ring of the cutterhead defines an annular channel for receiving loosened material.

主权项

1. A dredge cutterhead comprising:
(a) a hub, a ring, and a plurality of helical arms interconnecting said hub and said ring; (b) each of said helical arms having a leading edge for attachment of cutting teeth,and a trailing edge, and at least some of the helical arms being driving helical arms each having a trough portion located between said leading and trailing edges and extending along said driving helical arm toward said ring, each said trough portion being substantially free from structures obstructing movement of material along said driving helical arm toward said ring, and each said trough portion having a degree of curvature of between about 10% to about 25%; and (c) each of said driving helical arms being shaped such that said leading edge of a part of a respective driving helical arm near said ring trails behind said leading edge of a part of said respective helical arm near said hub as said cutterhead is rotated about a rotational axis thereof, and a net force exerted on dredged material in said trough portion pushes said material toward said ring generally along the center of said trough portion as said cutterhead is rotated.