Suction dredge cutter head

For use with a suction dredge having a suction pipe, the combination comprising:

• a driven cutter head of open-work construction which encloses and is rotatable adjacent the mouth of the pipe about an axis generally parallel to the axis of the pipe, said head comprising a plurality of digging arms which spiral divergently rearward from hub means forward of the mouth and recede rearward of the direction of their rotation;
• and
• crusher means of grid-like open-work construction within said head and cooperating with said arms to crush, on relative rotation between said head and crusher means, large objects dug by and passing through said head in order to minimize damage and clogging of suction and discharge lines and the dredge pump of the dredge, said crusher means being of generally frusto-conical configuration and generally-coaxial with said head, and provided with interconnecting generally circumferential and generally longitudinal bars, whereby said arms sweep large objects into the clearance between said arms and bars so as to exert a crushing action which breaks the objects into smaller pieces which can pass through the openings in said crusher means and into the mouth of the pipe.