To mechanically assist the suction action of a dredge head in dislodging particles embedded, e.g., on the ocean floor, a plurality of fingers extend downwardly from along the upper edge of an obliquely downwardly and forwardly facing nozzle opening. The fingers are resiliently connected to the nozzle and thus are capable of being bent downwardly so as to be juxtaposed across and thus temporarily block, the nozzle opening, whereby the intake of oversized particles is prevented.

A liquid inlet adapted to fit over the intake end of a suction hose for a portable dredging machine. The inlet is elbow shaped, having a discharge end mountable to the dredging machine suction hose. The opposite end of the inlet includes a set of spiral-shaped fingers that are powered to rotate in front of an open intake end. The fingers are rotated by a hand-held drive motor on a shaft that passes through a portion of the elbow. The rotating fingers strain material drawn into the elbow and suct...

A phase angle monitoring apparatus for phase monitoring a vibratory system includes a controller that produces a phase angle control signal representative of the lead or lag between the vibratory movement of two vibrating masses. The phase angle control signal is coupled to at least one of the vibrating masses to adjust the vibration of the mass to produce a desired phase angle, for example one-hundred eighty degrees (180.degree.).

Dredging apparatus comprises a modular, submersible, vertically positionable crater sink mechanism operable to form a crater in a bed of material beneath a body of water. The crater sink mechanism comprises an elongated tubular housing closed at its upper end and having a dredged material intake opening at its lower end. An auger mounted in the material intake opening is rotatable by a reversible hydraulic drive motor and is axially positionable by a linear hydraulic motor. The inner end of the ...

A floating dredge has a downwardly extending discharge line terminating in a double ended scoop, with the discharge line being supported at its upper end for bi-directional swinging movement of the scoop; the scoop having a pivoted double ended scraper blade which alternatively opens one end of the scoop while closing the other.

A dredging head with a pivotally mounted mud shield and cooperating intake assembly. A head located at the end of a dredge boom has digging and conveying screw augers attached to a rotating shaft to loosen material such as mud, silt, and weeds from the bottom of a body of water and convey it toward an intake assembly which includes a suction intake conduit, a rotor, a stationary anvil, and an arcuate bar assembly. The mud shield confines material near the augers so the material can be conveyed b...

The present invention pertains to debris exclusion devices designed for use on a small augerhead type hydraulic dredge system for operations in debris laden channels that can cause the system's pump to malfunction. Debris to be excluded by these devices include portions of trees, woody-stemmed plants, pieces of lumber, pieces of metal or even unexploded ordinance. A first embodiment comprises vertical grates with curved front surfaces mounted in front of a spoils inlet of a dredgehead shroud wit...

A placer stream dredging head including a relatively short section of open end pipe coaxially secured to the depending end of a boat supported gangue tube. A closed bottom cage is connected with the depending end of the pipe section. A first force pump supplied water pressure hose is connected with the upper end portion of the pipe section in a manner to induce a jet action pressure reduction for lifting gangue into the gangue tube. A second force pump supplied water pressure hose is secured to ...

Apparatus for digging a hole beneath the water comprises a submarine motor connected to drive a shaft carrying a plurality of scoops provided with teeth along their cutting edges. The scoops are mounted beneath a stationary disc provided with a hole connected to a suction pipe through which sand displaced by the scoops may be sucked up.

Improvement in undersea mining apparatus, of the kind wherein a hydraulic suction conduit riser is towed from a forwardly moving surface ship while a mixture of liquids and sea-floor solids (such as sea water and manganese nodules) is gathered at the deep sea floor and transported to the sea surface in a liquid-solids flow pumped up through the riser, comprises liquid-solids flow transition chamber that is connected to riser by an intermediate conveyance duct and towed along the undersea floor t...