Patent ID: 6860042
Filing Date: 2005-03-01
Classification: E02F

Abstract:
1. An excavation system comprising: (1) a bucket which defines an outlet at its base, (2) a suction tube in fluid communication with a jet pump and with the bucket outlet, and (3) a guard for sieving excavated material before the excavated material enters the bucket outlet, wherein the jet pump is comprised of a nozzle assembly which is sized and configured to (i) receive a pressurized liquid and a gas, and (ii) eject the pressurized liquid as a liquid flow while feeding the gas into proximity with the periphery of the liquid flow, so that when the jet pump creates a vacuum in the suction tube, the material in the bucket which can pass through the guard is suctioned through the outlet, and wherein the jet pump further comprises a housing defining a suction chamber into which the nozzle assembly may eject the liquid flow, the housing further defining a suction inlet and a suction outlet; and an outlet pipe extending from the suction outlet away from the suction chamber, the outlet pipe being configured for fluid communication with the suction chamber and being disposed to receive the liquid flow; the outlet pipe defining at least a first inner diameter along a portion of its length and a second inner diameter along another portion of its length, the second inner diameter being less than the first inner diameter.