Abstract: An apparatus for continuously dredging submarine mineral deposit comprising plural pairs of pulleys, each of which is pivoted coaxially at a preset distance. Plural pairs of specific endless ropes are adapted to be brought into contact with said pulleys and to be driven in translation movement with each other. Means is provided for preventing slippage between said ropes. When buckets for scraping up ores are being circulated between the upper deck of a barge and the seabed, said endless ropes are directed to travel downward from the upper part in a diagonally rearward direction. Also provided is an ore discharging chute adjacent to a spot where each of said buckets begins to glide down.

Abstract: Apparatus for extracting mineral resources lying on the bottom of sea into a working ship floating on an ocean utilizing circulating current based on the difference of water levels. A hollow box shaped tank has its bottom opened and sunk liftably into the sea bottom through a rope from the working ship. The tank is equipped with a rotatory driving mechanism and trawled along the sea bottom while stirring it when the ship travels on the ocean. An elongated flexible coaxial pipe comprises an inner pipe and a coaxial outer pipe, each having at its lower end a fanwise shaped hopper mouth disposed within the tank through the upper wall thereof. The coaxial pipe passes through an internal seawater cistern in the bottom wall portion of the working ship and has its upper portion within an external seawater cistern mounted on the upper portion of the working ship. A suction pump is joined to the upper end of the coaxial inner pipe.