Patent ID: 6482054
Filing Date: 2002-11-19
Classification: B63C,B63H,F16C

Abstract:
Tunnel thruster for a water craft comprising:a tunnel to be fitted into the water craft; a water tight motor housing having two ends, said motor housing mounted in said tunnel; at least one strut attached between said tunnel and said motor housing to mount and secured said motor housing in said tunnel, said at least one strut including a pathway for electric and instrumentation lines; two electric motors each including a drive shaft extending from an end of said motor, said motors mounted in an inline position along a centerline of said tunnel inside said motor housing, such that said drive shafts of said motors extend from each end of said motor housing along said centerline; and a water lubricated rotor duct assembly mounted on each end of said motor housing comprising: a rotor attached to said drive shaft and about said motor housing, said rotor having a main body which includes a front and a rear, and said front having a face; at least two blades extending from said main body of said rotor between said front and said rear of said main body of said rotor; a stabilizer shaft extending away from said motor housing, said stabilizer shaft extending from a center of said face of said front of said main body of said rotor, said stabilizer shaft having a nose at an end of said stabilizer shaft which is forward of said face; a cavity milled in said rear of said main body of said rotor to receive said drive shaft, at least part of said motor drive housing, bearings and seals, such that said main body of said rotor is mounted over said motor housing and internally connected to the nose of said drive shaft; a rear seal assembly applying a seal against said drive shaft and against said cavity of said main body of said rotor; a rear journal bearing providing a bearing surface between said cavity of said main body of said rotor and said motor drive housing, said rear journal positioned near said rear of said main body of said rotor, said rear journal bearing lubricated by water surrounding said rotor duct assembly; an inlet duct for attachment to the water craft to support said rotor duct assembly, said inlet duct including an outer rim and a center hub centered in said outer rim, said outer rim for attachment to the water craft and for supporting said center hub, said center hub for supporting said stabilizer shaft of said rotor, said center hub having a front and a rear, said rear of said center hub including a cavity milled to receive bearings; a forward bearing assembly in said cavity of said center hub, said forward bearing assembly lubricated by water surrounding said rotor duct assembly; a thrust shoulder attached to said nose of said stabilizer shaft at said front of said center hub, said thrust shoulder having a front and a rear, said rear of said thrust shoulder milled to receive said nose of said stabilizer shaft, said thrust shoulder having a nose at said front of said thrust shoulder, said thrust shoulder aiding in retaining said forward bearing assembly in place; a forward seal assembly to receive said nose of said thrust shoulder; and a duct cover which attaches to said front of said center hub and over said thrust shoulder, said duct cover having a front and a rear, said rear of said duct cover including a cavity milled to receive said forward seal assembly and said thrust shoulder.